liu.seSök publikationer i DiVA
Ändra sökning
Avgränsa sökresultatet
1 - 36 av 36
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Träffar per sida
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
Markera
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Nagi, Saad
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Univ Sydney, Australia.
    Marshall, Andrew G.
    Univ Manchester, England; Liverpool John Moores Univ, England.
    Makdani, Adarsh
    Liverpool John Moores Univ, England.
    Jarocka, Ewa
    Umea Univ, Sweden.
    Liljencrantz, Jaquette
    Natl Ctr Complementary and Integrat Hlth, MD 20892 USA; Univ Gothenburg, Sweden.
    Ridderstrom, Mikael
    Umea Univ Hosp, Sweden.
    Shaikh, Sumaiya
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Univ Sydney, Australia.
    ONeill, Francis
    Univ Liverpool, England.
    Saade, Dimah
    NINDS, MD 20892 USA.
    Donkervoort, Sandra
    NINDS, MD 20892 USA.
    Foley, A. Reghan
    NINDS, MD 20892 USA.
    Minde, Jan
    Umea Univ Hosp, Sweden.
    Trulsson, Mats
    Karolinska Inst, Sweden.
    Cole, Jonathan
    Bournemouth Univ, England.
    Bonnemann, Carsten G.
    NINDS, MD 20892 USA.
    Chesler, Alexander T.
    Natl Ctr Complementary and Integrat Hlth, MD 20892 USA.
    Bushnell, M. Catherine
    Natl Ctr Complementary and Integrat Hlth, MD 20892 USA.
    McGlone, Francis
    Liverpool John Moores Univ, England; Univ Liverpool, England.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurofysiologiska kliniken US.
    An ultrafast system for signaling mechanical pain in human skin2019Ingår i: Science Advances, E-ISSN 2375-2548, Vol. 5, nr 7, artikel-id eaaw1297Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The canonical view is that touch is signaled by fast-conducting, thickly myelinated afferents, whereas pain is signaled by slow-conducting, thinly myelinated ("fast" pain) or unmyelinated ("slow" pain) afferents. While other mammals have thickly myelinated afferents signaling pain (ultrafast nociceptors), these have not been demonstrated in humans. Here, we performed single-unit axonal recordings (microneurography) from cutaneous mechanoreceptive afferents in healthy participants. We identified A-fiber high-threshold mechanoreceptors (A-HTMR5) that were insensitive to gentle touch, encoded noxious skin indentations, and displayed conduction velocities similar to A-fiber low-threshold mechanoreceptors. Intraneural electrical stimulation of single ultrafast A-HTMRs evoked painful percepts. Testing in patients with selective deafferentation revealed impaired pain judgments to graded mechanical stimuli only when thickly myelinated fibers were absent. This function was preserved in patients with a loss-of-function mutation in mechanotransduction channel PIEZO2.These findings demonstrate that human mechanical pain does not require PIEZO2 and can be signaled by fast-conducting, thickly myelinated afferents.

  • 2.
    Taneja, Pankaj
    et al.
    Aarhus Univ, Denmark; SCON, Denmark.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurofysiologiska kliniken US.
    Trulsson, Mats
    SCON, Denmark; Karolinska Inst, Sweden.
    Vase, Lene
    Aarhus Univ, Denmark.
    Svensson, Peter
    Aarhus Univ, Denmark; SCON, Denmark; Karolinska Inst, Sweden.
    Baad-Hansen, Lene
    Aarhus Univ, Denmark; SCON, Denmark.
    Assessment of experimental orofacial pain, pleasantness and unpleasantness via standardized psychophysical testing2019Ingår i: European Journal of Pain, ISSN 1090-3801, E-ISSN 1532-2149, Vol. 23, nr 7, s. 1297-1308Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background Somatosensory assessment within the orofacial region may be performed using highly standardized quantitative sensory testing (QST). However, the function of the C-tactile (CT) afferent, a nerve fibre linked to the perception of pleasant touch, is usually not evaluated. Furthermore, the perception of unpleasantness is also rarely assessed, a dimension not only limited to a painful experience. Therefore, the primary aim was to apply standardized QST stimuli as well as standardized pleasant stimuli and evaluate their potential capacity for evocation of perceived pain, pleasant and unpleasant sensations in the facial region. Methods Twenty-one female participants underwent QST as per the protocol derived from the German Research Network on Neuropathic Pain. For the first time, two modified protocols were used to investigate stimuli for perceived pleasantness and unpleasantness. Results Thermal stimuli provided separate thresholds for each sensation. From certain mechanical stimuli (e.g., vibration), overlap between the perceived sensations of pleasantness and unpleasantness was identified. It was not possible to evoke only an unpleasant sensation without a painful contribution, and both these sensations increased significantly when utilizing an increasing pinprick force (p amp;lt; 0.011). Between dynamic stimuli, the brush was rated as significantly more pleasant than the cotton wool tip (p = 0.015). A quadratic model provided the best fit for velocity against mean pleasantness ratings (R-2 = 0.62 +/- 0.08), supporting previous CT afferent literature to some extent. Conclusion Stimuli were generally not isolated to one sensation, highlighting the multidimensional construct of stimulus perception and the need for scales to capture this. Significance The battery of QST tests from the DFNS protocol has been modified to investigate pleasant and unpleasant sensations. This allows the evaluation of psychophysical properties across standardized dimensions to provide a thorough view of somatosensory function and to better understand the affective spectrum of somatosensory function.

  • 3.
    Strauss, Timmy
    et al.
    Tech Univ Dresden, Germany.
    Kämpe, Robin
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Hamilton, Paul
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Rottstaedt, Fabian
    Tech Univ Dresden, Germany.
    Raue, Claudia
    Tech Univ Dresden, Germany.
    Croy, Ilona
    Tech Univ Dresden, Germany.
    Deactivation of default mode network during touch2019Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, artikel-id 1293Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Interpersonal touch possesses a strong affective component, which immediately evokes attention. The neural processing of such touch is moderated by specialized C-tactile nerve fibers in the periphery and results in central activation of somatosensory areas as well as regions involved in social processing, such as the superior temporal gyrus (STG). In the present functional neuroimaging investigation, we tested the hypothesis that the attention grasping effect of interpersonal touch as compared to impersonal touch is reflected in a more-pronounced deactivation of the default mode network (DMN). Using functional magnetic resonance imaging, we investigated the neural processing of interpersonal relative to impersonal touch conditions that were furthermore modulated by stroking velocity in order to target c-tactile nerve fibers to a different extent. A sample of 30 healthy participants (19 women, mean age 40.5 years) was investigated. In the impersonal touch, participants were stroked with a brush on the forearm. In the interpersonal touch condition, the experimenter performed the stroking with the palm of his hand. Interpersonal touch was rated as more pleasant and intense than impersonal touch and led to a stronger blood oxygen level dependent (BOLD) signal increase in the somatosensory cortex SII extending to the superior temporal cortex. Over all touch conditions, this activation was coupled in time to the deactivation of prominent nodes of the DMN. Although deactivation of the DMN was most pronounced for interpersonal touch conditions, the direct comparison did not show significant differences in DMN deactivation between interpersonal and impersonal touch or between different stroking velocities. We therefore conclude that all applied touch conditions deactivate the DMN and the strong connection to areas which code the contextual and social characteristics of affective touch may explain the attention grasping effect of touch.

  • 4.
    Böhme, Rebecca
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Hauser, Steven
    Univ Virginia, VA 22904 USA.
    Gerling, Gregory J.
    Univ Virginia, VA 22904 USA.
    Heilig, Markus
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Närsjukvården i centrala Östergötland, Psykiatriska kliniken.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Region Östergötland, Sinnescentrum, Neurofysiologiska kliniken US.
    Distinction of self-produced touch and social touch at cortical and spinal cord levels2019Ingår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 116, nr 6, s. 2290-2299Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Differentiation between self-produced tactile stimuli and touch by others is necessary for social interactions and for a coherent concept of "self." The mechanisms underlying this distinction are unknown. Here, we investigated the distinction between self-and other-produced light touch in healthy volunteers using three different approaches: fMRI, behavioral testing, and somatosensory-evoked potentials (SEPs) at spinal and cortical levels. Using fMRI, we found self-other differentiation in somatosensory and sociocognitive areas. Other-touch was related to activation in several areas, including somatosensory cortex, insula, superior temporal gyrus, supramarginal gyrus, striatum, amygdala, cerebellum, and prefrontal cortex. During self-touch, we instead found deactivation in insula, anterior cingulate cortex, superior temporal gyrus, amygdala, parahippocampal gyrus, and prefrontal areas. Deactivation extended into brain areas encoding low-level sensory representations, including thalamus and brainstem. These findings were replicated in a second cohort. During self-touch, the sensorimotor cortex was functionally connected to the insula, and the threshold for detection of an additional tactile stimulus was elevated. Differential encoding of self-vs. other-touch during fMRI correlated with the individual self-concept strength. In SEP, cortical amplitudes were reduced during self-touch, while latencies at cortical and spinal levels were faster for other-touch. We thus demonstrated a robust self-other distinction in brain areas related to somatosensory, social cognitive, and interoceptive processing. Signs of this distinction were evident at the spinal cord. Our results provide a framework for future studies in autism, schizophrenia, and emotionally unstable personality disorder, conditions where symptoms include social touch avoidance and poor self-vs.-other discrimination.

  • 5.
    Croy, Ilona
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Tech Univ Dresden, Germany.
    Sehlstedt, Isac
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Univ Gothenburg, Sweden.
    Wasling, Helena Backlund
    Univ Gothenburg, Sweden.
    Ackerley, Rochelle
    Univ Gothenburg, Sweden; Aix Marseille Univ, France.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Gentle touch perception: From early childhood to adolescence2019Ingår i: Developmental Cognitive Neuroscience, ISSN 1878-9293, E-ISSN 1878-9307, Vol. 35, s. 81-86Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Affective touch plays an important role in childrens social interaction and is involved in shaping the development of the social brain. The positive affective component of touch is thought to be conveyed via a group of unmyelinated, low-threshold mechanoreceptive afferents, known as C-tactile fibers that are optimally activated by gentle, slow, stroking touch. Touch targeting these C-tactile fibers has been shown to decrease the heart rate in infants. The current study investigated the relationship between age and psychophysical ratings in response to affective touch. A total of n = 43 participants (early childhood: aged 5-8 years, 9 girls, 12 boys; late childhood: aged 9-12 years, 12 girls, 10 boys) were presented with C-tactile optimal and sub-optimal stroking velocities and rated touch pleasantness on an affective pictorial scale. For both age groups, we found that children preferred C-tactile-targeted stimulation. A comparison with previously published data showed that the childrens preference for C-tactile-targeted stimulation was similar to those obtained in adolescents and adults. We speculate that the effect of C-tactile-targeted touch, which is linked with pleasantness, shapes the childrens preference for C-tactile over non-C-tactile-targeted stimulation, and that C-tactile afferent stimulation is important for social development.

  • 6.
    Davidovic, Monika
    et al.
    Univ Gothenburg, Sweden.
    Starck, Goran
    Univ Gothenburg, Sweden; Sahlgrens Univ Hosp, Sweden.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Univ Gothenburg, Sweden.
    Processing of affective and emotionally neutral tactile stimuli in the insular cortex2019Ingår i: Developmental Cognitive Neuroscience, ISSN 1878-9293, E-ISSN 1878-9307, Vol. 35, s. 94-103Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The insula is important for the processing of pleasant aspects of touch whereas its role in the processing of emotionally neutral touch has been less explored. Here, we used a network approach to investigate the insular processing of pleasant stroking touch and emotionally neutral vibratory touch, analysing functional magnetic resonance imaging data from 23 healthy adult participants. Vibration and skin stroking activated areas in the posterior, middle and anterior insula. Psychophysiological interaction analyses suggested that skin stroking increased functional connectivity between the posterior and ventral anterior insula. Vibration instead increased functional connectivity between the posterior and dorsal anterior insula, and induced a stronger decrease of the default mode network activity compared to stroking. These results confirmed findings from previous studies showing that the posterior insula processes affective touch information. We suggest that this is accomplished by relaying tactile information from the posterior insula to ventral anterior insula, an area tightly connected to the emotional parts of the brain. However, our results also suggested that the insula processes tactile information with less emotional valence. A central hub in this processing seemed to be the right dorsal anterior insula.

  • 7.
    Ree, Anbjorn
    et al.
    Univ Oslo, Norway.
    Morrison, India
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Sailer, Uta
    Univ Oslo, Norway.
    Heilig, Markus
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Närsjukvården i centrala Östergötland, Psykiatriska kliniken.
    Mayo, Leah
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Using Facial Electromyography to Assess Facial Muscle Reactions to Experienced and Observed Affective Touch in Humans2019Ingår i: Journal of Visualized Experiments, ISSN 1940-087X, E-ISSN 1940-087X, nr 145, artikel-id e59228Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Affective

  • 8.
    Davidovic, Monika
    et al.
    Univ Gothenburg, Sweden.
    Karjalainen, Louise
    Univ Gothenburg, Sweden.
    Starck, Göran
    Univ Gothenburg, Sweden; Sahlgrens Univ Hosp, Sweden.
    Wentz, Elisabet
    Univ Gothenburg, Sweden.
    Björnsdotter Åberg, Malin
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Univ Gothenburg, Sweden.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurofysiologiska kliniken US. Univ Gothenburg, Sweden.
    Abnormal brain processing of gentle touch in anorexia nervosa2018Ingår i: Psychiatry Research: Neuroimaging, ISSN 0925-4927, E-ISSN 1872-7506, Vol. 281, s. 53-60Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Body image disturbance is a core symptom in anorexia nervosa (AN). Recent research suggests that abnormalities in touch perception may contribute to the disease mechanisms in AN. Here, we used functional magnetic resonance imaging (fMRI) to study possible abnormalities in cortical processing of affective touch in AN. Gentle skin strokes were applied to the right forearm during fMRI scanning in women diagnosed with AN (n = 25) and in matched healthy controls (HC; n = 25). Blocks of skin stroking were alternated with blocks of static skin indentation. Participants provided ratings of the pleasantness of skin stroking stimulation. AN participants perceived skin stroking as significantly less pleasant than HC. We observed no group differences for the contrast between skin stroking and skin indentation in primary tactile regions. We did find, however, significantly less activity in the AN group in areas including left caudate nucleus. Also, we found less activity in the AN group in bilateral lateral occipital cortex for the main effect of skin stroking. Our results suggest that abnormal functioning of the dorsal striatum could affect evaluation of pleasant tactile stimuli, and that abnormal functioning of the lateral occipital cortex might be related to disturbed body image perception.

  • 9.
    Jonsson, Emma H.
    et al.
    Univ Gothenburg, Sweden.
    Kotilahti, Kalle
    Aalto Univ, Finland.
    Heiskala, Juha
    Univ Helsinki, Finland.
    Wasling, Helena Backlund
    Univ Gothenburg, Sweden.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurofysiologiska kliniken US. Univ Gothenburg, Sweden.
    Croy, Ilona
    Tech Univ Dresden, Germany.
    Mustaniemi, Hanna
    Aalto Univ, Finland.
    Hiltunen, Petri
    Aalto Univ, Finland.
    Tuulari, Jetro J.
    Univ Turku, Finland.
    Scheinin, Noora M.
    Univ Turku, Finland; Turku Univ Hosp, Finland.
    Karlsson, Linnea
    Univ Turku, Finland; Turku Univ Hosp, Finland.
    Karlsson, Hasse
    Univ Turku, Finland; Turku Univ Hosp, Finland.
    Nissila, Ilkka
    Aalto Univ, Finland.
    Affective and non-affective touch evoke differential brain responses in 2-month-old infants2018Ingår i: NeuroImage, ISSN 1053-8119, E-ISSN 1095-9572, Vol. 169, s. 162-171Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Caressing touch is an effective way to communicate emotions and to create social bonds. It is also one of the key mediators of early parental bonding. The caresses are generally thought to represent a social form of touching and indeed, slow, gentle brushing is encoded in specialized peripheral nerve fibers, the C-tactile (CT) afferents. In adults, areas such as the posterior insula and superior temporal sulcus are activated by affective, slow stroking touch but not by fast stroking stimulation. However, whether these areas are activated in infants, after social tactile stimulation, is unknown. In this study, we compared the total hemoglobin responses measured with diffuse optical tomography (DOT) in the left hemisphere following slow and fast stroking touch stimulation in 16 2-month-old infants. We compared slow stroking (optimal CT afferent stimulation) to fast stroking (non-optimal CT stimulation). Activated regions were delineated using two methods: one based on contrast between the two conditions, and the other based on voxel-based statistical significance of the difference between the two conditions. The first method showed a single activation cluster in the temporal cortex with center of gravity in the middle temporal gyrus where the total hemoglobin increased after the slow stroking relative to the fast stroking (p = 0.04 uncorrected). The second method revealed a cluster in the insula with an increase in total hemoglobin in the insular cortex in response to slow stroking relative to fast stroking (p = 0.0005 uncorrected; p = 0.04 corrected for multiple comparisons). These activation clusters encompass areas that are involved in processing of affective, slow stroking touch in the adult brain. We conclude that the infant brain shows a pronounced and adult-like response to slow stroking touch compared to fast stroking touch in the insular cortex but the expected response in the primary somatosensory cortex was not found at this age. The results imply that emotionally valent touch is encoded in the brain in adult-like manner already soon after birth and this suggests a potential for involvement of touch in bonding with the caretaker.

  • 10.
    Björnsdotter Åberg, Malin
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Karolinska Inst, Sweden.
    Davidovic, Monika
    Univ Gothenburg, Sweden.
    Karjalainen, Louise
    Univ Gothenburg, Sweden.
    Starck, Goran
    Univ Gothenburg, Sweden.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurofysiologiska kliniken US. Univ Gothenburg, Sweden.
    Wentz, Elisabet
    Univ Gothenburg, Sweden; Sahlgrens Univ Hosp, Sweden.
    Grey matter correlates of autistic traits in women with anorexia nervosa2018Ingår i: Journal of Psychiatry & Neuroscience, ISSN 1180-4882, E-ISSN 1488-2434, Vol. 43, nr 2, s. 79-86Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Patients with anorexia nervosa exhibit higher levels of behaviours typically associated with autism-spectrum disorder (ASD), but the neural basis is unclear. We sought to determine whether elevated autistic traits in women with anorexia nervosa may be reflected in cortical morphology. Methods: We used voxel-based morphometry (VBM) to examine regional grey matter volumes in high-resolution MRI structural brain scans in women with anorexia nervosa and matched healthy controls. The Autism-spectrum Quotient (AQ) scale was used to assess autistic traits. Results: Women with anorexia nervosa (n = 25) had higher AQ scores and lower bilateral superior temporal sulcus (STS) grey matter volumes than the control group (n = 25). The AQ scores correlated negatively with average left STS grey matter volume in women with anorexia nervosa. Limitations: We did not control for cognitive ability and examined only women with ongoing anorexia nervosa. Conclusion: Elevated autistic traits in women with anorexia nervosa are associated with morphometric alterations of brain areas linked to social cognition. This finding provides neurobiological support for the behavioural link between anorexia nervosa and ASD and emphasizes the importance of recognizing autistic traits in preventing and treating-anorexia nervosa.

  • 11.
    Mayo, Leah
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Lindé, Johan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurofysiologiska kliniken US.
    Heilig, Markus
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Närsjukvården i centrala Östergötland, Psykiatriska kliniken.
    Morrison, India
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Putting a good face on touch: Facial expression reflects the affective valence of caress-like touch across modalities2018Ingår i: Biological Psychology, ISSN 0301-0511, E-ISSN 1873-6246, Vol. 137, s. 83-90Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Touch plays a central role in interpersonal behavior, especially in its capacity to convey-and induce- changes in affect. Previous research has established that slow, caress-like stroking over the skin elicits positive subjective affective responses, with higher ratings of "pleasantness" compared to a faster-moving touch stimulus. Ratings of pleasantness are associated with increased activity of a distinct class of nerve fibers: C-tactile (CT) afferents. Here, we used facial electromyography (EMG) to determine if touch that optimally activates CT afferents also influences facial muscle activity believed to reflect changes in affect. We found that less pleasant, fast-moving stroking (30 cm/s) elicited robustly negative facial EMG responses, as indexed by stronger contraction of the corrugator muscle. In contrast, pleasant, slow-moving stroking (3 cm/s) that optimally activates CT afferents resulted in decreased negative facial affective responses, manifested as significant corrugator relaxation compared to fast stroking. Moreover, the facial tracking of affective valence during touch was supra-modal, with similar effects during both directly-experienced touch and viewing of touch videos. The results of this EMG study imply that touch that fails to optimally activate CT afferent produces a negative affective response, whereas pleasant, caress-like touch has not only subjective but expressive correlates, reflected in net positive affective changes in facial expression.

  • 12.
    Lee, Ye-Seul
    et al.
    Kyung Hee Univ, South Korea.
    Sehlstedt, Isac
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. University of Gothenburg, Gothenburg, Sweden.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurofysiologiska kliniken US.
    Jung, Won-Mo
    Kyung Hee Univ, South Korea.
    Wallraven, Christian
    Korea Univ, South Korea.
    Chae, Younbyoung
    Kyung Hee Univ, South Korea.
    Visual and physical affective touch delivered by a rotary tactile stimulation device: A human psychophysical study2018Ingår i: Physiology and Behavior, ISSN 0031-9384, E-ISSN 1873-507X, Vol. 185, s. 55-60Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The discovery that pleasant touch is coded by C-tactile fibers has generated considerable research interest and increased understanding of the skin as a channel for social information via cutaneous senses. However, no study has differentiated between the pleasant response to visual and tactile non-human stimulations. Our study investigated pleasant touch in which the visual and haptic touch information was obtained from an affective, but non-social experience, by a custom-built non-human device. Participants (n = 19) received soft brush strokes on their lower left arm delivered by a rotary tactile stimulator (physical session) or watched a video of an arm being stroked by a rotary tactile stimulator (visual session). The brush strokes were delivered at the same velocities (0.3, 1, 3, 10, 30 cm/s) and force (0.4 N) in both sessions. After each trial, participants rated the pleasantness of the touch. Analysis of variance was used to assess the effects of velocity and modality (visual touch vs. physical touch) on the pleasantness rating. Participants rated strokes between 1 and 10 cm/s as most pleasant under both conditions. The pleasantness rating patterns differed significantly among velocities; however, no significant differences were found between modalities. Visual and physical (without human-to-human interaction) touch elicited similar behavioral responses, including an inverted U-shaped perception of pleasantness. These findings suggest that the pleasantness of touch is influenced by the velocity of the strokes in both visual and physical touch with a non-human stimulation.

  • 13.
    Bendas, Johanna
    et al.
    Technical University of Dresden, Germany.
    Georgiadis, Janniko R.
    University of Medical Centre Groningen, Netherlands.
    Ritschel, Gerhard
    Technical University of Dresden, Germany.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Weidner, Kerstin
    Technical University of Dresden, Germany.
    Croy, Ilona
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Technical University of Dresden, Germany.
    C-Tactile Mediated Erotic Touch Perception Relates to Sexual Desire and Performance in a Gender-Specific Way2017Ingår i: Journal of Sexual Medicine, ISSN 1743-6095, E-ISSN 1743-6109, Vol. 14, nr 5, s. 645-653Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Unmyelinated low-threshold mechanoreceptors-the so-called C-tactile (CT) afferents-play a crucial role in the perception and conduction of caressing and pleasant touch sensations and significantly contribute to the concept of erotic touch perception. Aim: To investigate the relations between sexual desire and sexual performance and the perception of touch mediated by CT afferents. Methods: Seventy healthy participants (28 men, 42 women; mean age+/-SD = 24.84+/-4.08 years, range = 18-36 years) underwent standardized and highly controlled stroking stimulation that varied in the amount of CT fiber stimulation by changing stroking velocity (CT optimal = 1, 3 and 10 cm/s; CT suboptimal = 0.1, 0.3, and 30 cm/s). Participants rated the perceived pleasantness, eroticism, and intensity of the applied tactile stimulation on a visual analog scale, completed the Sexual Desire Inventory, and answered questions about sexual performance. Outcomes: Ratings of perceived eroticism of touch were related to self-report levels of sexual desire and sexual performance. Results: Pleasantness and eroticism ratings showed similar dependence on stroking velocity that aligned with the activity of CT afferents. Erotic touch perception was related to sexual desire and sexual performance in a gender-specific way. In women, differences in eroticism ratings between CT optimal and suboptimal velocities correlated positively with desire for sexual interaction. In contrast, in men, this difference correlated to a decreased frequency and longer duration of partnered sexual activities. Clinical Implications: The present results lay the foundation for future research assessing these relations in patients with specific impairments of sexual functioning (eg, hypoactive sexual desire disorder). Strengths and Limitations: The strength of the study is the combination of standardized neurophysiologic methods and behavioral data. A clear limitation of the study design is the exclusion of exact data on the female menstrual cycle and the recruitment of an inhomogeneous sample concerning sexual orientation. Conclusion: The present results provide further evidence that unmyelinated CT afferents play a role in the complex mechanism of erotic touch perception. The ability to differentiate between CT optimal and suboptimal stimuli relates to sexual desire and performance in a gender-specific way. Copyright (C) 2017, International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

  • 14.
    Triscoli, Chantal
    et al.
    University of Gothenburg, Sweden; Sahlgrens University Hospital, Sweden.
    Croy, Ilona
    Technical University of Dresden, Germany.
    Steudte-Schmiedgen, Susann
    Technical University of Dresden, Germany.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Sahlgrens University Hospital, Sweden.
    Sailer, Uta
    University of Gothenburg, Sweden; University of Oslo, Norway.
    Heart rate variability is enhanced by long-lasting pleasant touch at CT-optimized velocity2017Ingår i: Biological Psychology, ISSN 0301-0511, E-ISSN 1873-6246, Vol. 128, s. 71-81Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Introduction: The present study explores whether long-lasting pleasant touch has positive effects on the stress response, reward sensitivity, mood, and interoceptive awareness. Methods: 40 participants received either 35 min of brush stroking targeting C-tactile fibres (CT) or vibration on the forearm, and rated pleasantness and intensity. Prior and after, stress response (cortisol and heart rate variability), reward sensitivity, mood and interoceptive awareness were measured. Results: Pleasantness decreased over time for both groups, with brush stroking being perceived as more pleasant and intense than vibration. Heart rate variability (SDNN) increased for brush stroking only, and was related to the higher pleasantness and intensity. No significant effect of CT-optimal touch was observed on any of the other measures. Discussion: The beneficial effect of pleasant touch on heart rate variability suggests a neuronal link between CTfibre stimulation and autonomic regulation, and highlights the potential of long-lasting touch to improve the physiological response.

  • 15.
    Case, Laura K.
    et al.
    NIH, MD 20892 USA.
    Laubacher, Claire M.
    NIH, MD 20892 USA.
    Richards, Emily A.
    NIH, MD 20892 USA.
    Spagnolo, P. A.
    NIAAA, MD USA.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Bushnell, M. Catherine
    NIH, MD 20892 USA.
    Inhibitory rTMS of secondary somatosensory cortex reduces intensity but not pleasantness of gentle touch2017Ingår i: Neuroscience Letters, ISSN 0304-3940, E-ISSN 1872-7972, Vol. 653, s. 84-91Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Research suggests that the discriminative and affective aspects of touch are processed differently in the brain. Primary somatosensory cortex is strongly implicated in touch discrimination, whereas insular and prefronal regions have been associated with pleasantness aspects of touch. However, the role of secondary somatosensory cortex (S2) is less clear. In the current study we used inhibitory repetitive transcranial magnetic stimulation (rTMS) to temporarily deactivate S2 and probe its role in touch perception. Nineteen healthy adults received two sessions of 1-Hz rTMS on separate days, one targeting right S2 and the other targeting the vertex (control). Before and after rTMS, subjects rated the intensity and pleasantness of slow and fast gentle brushing of the hand and performed a 2-point tactile discrimination task, followed by fMRI during additional brushing. rTMS to S2 (but not vertex) decreased intensity ratings of fast brushing, without altering touch pleasantness or spatial discrimination. MRI showed a reduced response to brushing in S2 (but not in S1 or insula) after S2 rTMS. Together, our results show that reducing touch evoked activity in S2 decreases perceived touch intensity, suggesting a causal role of S2 in touch intensity perception. Published by Elsevier Ireland Ltd.

  • 16.
    Habig, Kathrin
    et al.
    Justus Liebig University, Germany.
    Schaenzer, Anne
    Justus Liebig University, Germany.
    Schirner, Wolfgang
    Justus Liebig University, Germany.
    Lautenschlaeger, Gothje
    Justus Liebig University, Germany.
    Dassinger, Benjamin
    Justus Liebig University, Germany.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Birklein, Frank
    Johannes Gutenberg University of Mainz, Germany.
    Gizewski, Elke R.
    Medical University of Innsbruck, Austria.
    Kraemer, Heidrun H.
    Justus Liebig University, Germany.
    Low threshold unmyelinated mechanoafferents can modulate pain2017Ingår i: BMC Neurology, ISSN 1471-2377, E-ISSN 1471-2377, Vol. 17, artikel-id 184Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Human, hairy skin contains a subgroup of C-fibers, the C-low threshold mechanoreceptive afferents ((C-LTMR) C-tactile or C-touch (CT) fibers) that are linked with the signaling of affective aspects of human touch. Recent studies suggest an involvement of these afferents in the modulation of pain in healthy volunteers. Small fiber neuropathy (SFN) is associated with a damage of C-fibers. Therefore, an impairment of C-LTMRs can be assumed. We aimed to elaborate a possible role of CT-afferents in pain modulation by investigating healthy volunteers and SFN-patients. Methods: Experiment I: 20 SFN-patients (12 women, median age 52.0 years) and 20 healthy controls (14 women, median age 43.0 years) participated in this prospective fMRI and psychophysical study. Heat-pain (HP), CT-targeted touch (slow brushing) and HP combined with CT-targeted touch were applied in randomized order to the left shank in a block design. The participants rated pain intensity on a visual analogue scale. Experiment II: We investigated a possible impact of pain intensity on CT induced pain modulation (10 healthy participants). The intensity of HP stimulation was chosen to induce pain intensity 50/100 (NRS). HP stimulation was applied with and without CT-targeted touch. Results: Experiment I: CT-stimulation was sufficient to reduce heat pain in healthy participants (p = 0.016), but not in SFN-patients. HP induced pain intensity was significantly higher (32,2 vs 52,6) in SFN-patients. During HP, bold responses in pain associated areas were observed in both groups. Additional CT-stimulation elicited no significant difference of bold responses compared to HP. Experiment II: In healthy volunteers, we reproduced a significant reduction of HP intensity by CT-stimulation (p = 0.038). Conclusions: CT input seems to be sufficient to modulate pain, independent of intensity of the pain stimulus. As a prerequisite, the CT fibers have to be intact as in healthy volunteers. If CT fibers are impaired -as in SFN-, CT-targeted touch does not modulate pain intensity. The location of CT-induced pain modulation might be attributed to the level of the dorsal horn since the cortical activation pattern of heat pain with and without CT-targeted touch did not differ in healthy subjects and in SFN-patients.

  • 17.
    Watkins, Roger H.
    et al.
    University of Gothenburg, Sweden; University of Bristol, England.
    Wessberg, Johan
    University of Gothenburg, Sweden.
    Backlund Wasling, Helena
    University of Gothenburg, Sweden.
    Dunham, James P.
    Cambridge University Hospital, England.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. University of Gothenburg, Sweden.
    Johnson, Richard D.
    University of Gothenburg, Sweden; University of Florida, FL 32610 USA.
    Ackerley, Rochelle
    University of Gothenburg, Sweden; Aix Marseille University, France.
    Optimal delineation of single C-tactile and C-nociceptive afferents in humans by latency slowing2017Ingår i: Journal of Neurophysiology, ISSN 0022-3077, E-ISSN 1522-1598, Vol. 117, nr 4, s. 1608-1614Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    C-mechanoreceptors in humans comprise a population of unmyelinated afferents exhibiting a wide range of mechanical sensitivities. C-mechanoreceptors are putatively divided into those signaling gentle touch (C-tactile afferents, CTs) and nociception (C-mechanosensitive nociceptors, CMs), giving rise to positive and negative affect, respectively. We sought to distinguish, compare, and contrast the properties of a population of human C-mechanoreceptors to see how fundamental the divisions between these putative subpopulations are. We used microneurography to record from individual afferents in humans and applied electrical and mechanical stimulation to their receptive fields. We show that C-mechanoreceptors can be distinguished unequivocally into two putative populations, comprising CTs and CMs, by electrically evoked spike latency changes (slowing). After both natural mechanical stimulation and repetitive electrical stimulation there was markedly less latency slowing in CTs compared with CMs. Electrical receptive field stimulation, which bypasses the receptor end organ, was most effective in classifying C-mechanoreceptors, as responses to mechanical receptive field stimulation overlapped somewhat, which may lead to misclassification. Furthermore, we report a subclass of low-threshold CM responding to gentle mechanical stimulation and a potential subclass of CT afferent displaying burst firing. We show that substantial differences exist in the mechanisms governing axonal conduction between CTs and CMs. We provide clear electrophysiological "signatures" (extent of latency slowing) that can be used in unequivocally identifying populations of C-mechanoreceptors in single-unit and multiunit microneurography studies and in translational animal research into affective touch. Additionally, these differential mechanisms may be pharmacologically targetable for separate modulation of positive and negative affective touch information. NEW amp; NOTEWORTHY Human skin encodes a plethora of touch interactions, and affective tactile information is primarily signaled by slowly conducting C-mechanoreceptive afferents. We show that electrical stimulation of low-threshold C-tactile afferents produces markedly different patterns of activity compared with high-threshold C-mechanoreceptive nociceptors, although the populations overlap in their responses to mechanical stimulation. This fundamental distinction demonstrates a divergence in affective touch signaling from the first stage of sensory processing, having implications for the processing of interpersonal touch.

  • 18.
    Liljencrantz, J.
    et al.
    University of Gothenburg, Sweden.
    Strigo, I.
    VA San Francisco Healthcare Syst, CA USA; University of Calif San Francisco, CA 94143 USA.
    Ellingsen, D. M.
    Harvard Medical Sch, MA USA; University of Oslo, Norway.
    Kraemer, H. H.
    Justus Liebig University, Germany.
    Lundblad, L. C.
    University of Gothenburg, Sweden.
    Nagi, Saad
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Western Sydney University, Australia.
    Leknes, S.
    University of Gothenburg, Sweden; University of Oslo, Norway.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. University of Gothenburg, Sweden.
    Slow brushing reduces heat pain in humans2017Ingår i: European Journal of Pain, ISSN 1090-3801, E-ISSN 1532-2149, Vol. 21, nr 7, s. 1173-1185Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: C-tactile (CT) afferents are unmyelinated low-threshold mechanoreceptors optimized for signalling affective, gentle touch. In three separate psychophysical experiments, we examined the contribution of CT afferents to pain modulation. Methods: In total, 44 healthy volunteers experienced heat pain and CT optimal (slow brushing) and CT sub-optimal (fast brushing or vibration) stimuli. Three different experimental paradigms were used: Concurrent application of heat pain and tactile (slow brushing or vibration) stimulation; Slow brushing, applied for variable duration and intervals, preceding heat pain; Slow versus fast brushing preceding heat pain. Results: Slow brushing was effective in reducing pain, whereas fast brushing or vibration was not. The reduction in pain was significant not only when the CT optimal touch was applied simultaneously with the painful stimulus but also when the two stimuli were separated in time. For subsequent stimulation, the pain reduction was more pronounced for a shorter time interval between brushing and pain. Likewise, the effect was more robust when pain was preceded by a longer duration of brush stimulation. Strong CT-related pain reduction was associated with low anxiety and high calmness scores obtained by a state anxiety questionnaire. Conclusions: Slow brushing - optimal for CT activation - is effective in reducing pain from cutaneous heating. The precise mechanisms for the pain relief are as yet unknown but possible mechanisms include inhibition of nociceptive projection neurons at the level of the dorsal horn as well as analgesia through cortical mechanisms.

  • 19.
    Luong, Amanda
    et al.
    Sahlgrens University Hospital, Sweden.
    Bendas, Johanna
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Technical University of Dresden, Germany; Dammstr 1, Germany.
    Etzi, Roberta
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. University of Milano Bicocca, Italy.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Sahlgrens University Hospital, Sweden.
    Croy, Ilona
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Technical University of Dresden, Germany.
    The individual preferred velocity of stroking touch as a stable measurement2017Ingår i: Physiology and Behavior, ISSN 0031-9384, E-ISSN 1873-507X, Vol. 177, s. 129-134Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Affective touch is of fundamental importance in human social interactions and there is an increasing interest in using touch as a probe for general affective perception. To this end, we developed a test of preferred velocity (ToP-V) of touch and tested whether the individually preferred stroking velocity is a stable and valid measurement. In study one, thirty healthy participants (18-30 years, 17 women) were examined with the ToP-V. Therefore, pairs of different slow stroking stimuli were presented by the Rotary Tactile Stimulator a robotic device - on the forearm and the participants chose the velocity they preferred in a forced choice paradigm. A retest was conducted after about 12 days. In study two, twenty-two healthy participants (20-43 years, 11 women) were tested with a shorter version of the ToP-V on the forearm and also on the palm. Moreover, they rated the pleasantness and the intensity of the stroking stimulations on both body sites. Results suggest that humans possess an individual and stable preferred velocity of stroking touch (test-retest reliability r = 0.86) which can be tested in a standardized procedure. A shortened 5 min version of the ToP-V also exhibited reasonable test characteristics (split half reliability: r = 0.7; test-retest reliability r = 0.77). The ToP-V correlated well with the pleasantness ratings when tested on the forearm (r = 0.65), but not when tested on the palm (r = 0.22), indicating that the ToP-V targets a C-tactile nerve fiber specific perception. Hence, the ToP-V can be used for reliably probing affective touch perception.

  • 20.
    Jonsson, Emma H.
    et al.
    University of Gothenburg, Sweden.
    Bendas, Johanna
    Technical University of Dresden, Germany.
    Weidner, Kerstin
    Technical University of Dresden, Germany.
    Wessberg, Johan
    University of Gothenburg, Sweden.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. University of Gothenburg, Sweden.
    Backlund Wasling, Helena
    University of Gothenburg, Sweden.
    Croy, Ilona
    Technical University of Dresden, Germany.
    The relation between human hair follicle density and touch perception2017Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, artikel-id 2499Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Unmyelinated low threshold C-tactile fibers moderate pleasant aspects of touch. These fibers respond optimally to stroking stimulation of the skin with slow velocities (1-10 cm/s). Low threshold mechanoreceptors are arranged around hair follicles in rodent skin. If valid also in humans, hair follicle density (HFD) may relate to the perceived pleasantness of stroking tactile stimulation. We conducted two studies that examined the relation between HFD and affective touch perception in humans. In total, 138 healthy volunteers were stroked on the forearm and rated the pleasantness and intensity. Stimulation was performed by a robotic tactile stimulator delivering C-tactile optimal (1, 3, 10 cm/s) and non-optimal (0.1, 0.3, 30 cm/s) stroking velocities. Additionally, a measure of discriminative touch was applied in study 2. HFD of the same forearm was determined using the Cyanoacrylate Skin Stripping Method (CSSM), which we validated in a pretest. Women had higher HFD than men, which was explained by body size and weight. Furthermore, women rated affective touch stimuli as more pleasant and had higher tactile acuity. Depilation did not affect touch perception. A weak relationship was found between the C-tactile specific aspects of affective touch perception and HFD, and the hypothesis of HFD relating to pleasant aspects of stroking only received weak support.

  • 21.
    Chae, Younbyoung
    et al.
    Kyung Hee University, South Korea.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    The role of touch in acupuncture treatment2017Ingår i: Acupuncture in Medicine, ISSN 0964-5284, E-ISSN 1759-9873, Vol. 35, nr 2, s. 148-152Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Acupuncture is a therapeutic treatment that is characterised by the insertion of a needle at a particular location on the body. Acupuncture stimulation includes sensory-discriminative and affective-social touch dimensions. In this review, we discuss the role of touch during acupuncture stimulation with an emphasis on the therapeutic, sensory-discriminative and affective-social aspects. In the discriminative dimension, de qi, which is associated with needling, includes a combination of various sensations, such as heaviness, numbness, soreness and distension. Achieving the appropriate de qi sensation appears to be fundamental to the therapeutic outcome following acupuncture treatment. In the affective dimension, the acupuncture procedure typically includes gentle manual touch stimulation, which induces feelings of calm and well-being, perhaps by activating C tactile fibres. Enhanced activity of C tactile afferents may induce a limbic touch response, resulting in emotional and hormonal reactions. Because acupuncture is a therapist intensive and complex intervention, it is necessary to understand the role of social touch between the practitioner and patient. Both sensory-discriminative and affective-social touch aspects play an important role in the therapeutic effect of acupuncture treatment in clinical practice.

  • 22.
    Triscoli, Chantal
    et al.
    University of Gothenburg, Sweden; Sahlgrens University Hospital, Sweden.
    Croy, Ilona
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Technical University of Dresden, Germany.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten. Sahlgrens University Hospital, Sweden.
    Sailer, Uta
    University of Oslo, Norway.
    Touch between romantic partners: Being stroked is more pleasant than stroking and decelerates heart rate2017Ingår i: Physiology and Behavior, ISSN 0031-9384, E-ISSN 1873-507X, Vol. 177, s. 169-175Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Introduction: Touch has been found to entail positive effects in the person receiving it, whereas effects on the person giving touch have previously been unexplored. We investigated whether stroking the partner also is a pleasant experience for the person performing it, and whether it has similar effects on well-being and autonomic nervous function as being stroked or stroking oneself. Furthermore, we compared the hedonic and autonomic nervous effects of strolcing the partner and self-stroking. Methods: In the first experiment, 40 subjects stroked the forearm of their respective partner, while ratings of pleasantness were obtained from both Stroker and Receiver. Heart rate was monitored throughout the session and stroking velocity was tracked. The participants could not see each other faces during the experiment to avoid feedback. In experiment 2, the design was replicated with 20 subjects, and self-stroking and rest conditions were added. Results: Both stroking the partner and self-stroking were performed within a velocity range optimal for activating C-tactile cutaneous afferents. Being stroked, stroking the partner, and self-stroking were all perceived as pleasant. However, being stroked entailed the significantly highest pleasantness ratings, and being stroked was the only condition that significantly decreased heart rate. Individuals in satisfying relationships were more pleased to be touched by their partner and showed a greater decline in heart rate when being touched. Discussion: The data demonstrated a role for affective touch in the regulation of heart rate when being stroked. The absence of autonomic effects when providing the stroking may be due to the absence of visual feedback from the person being stroked. The high pleasantness of giving and receiving touch may foster affective tactile interactions among romantic partners, thus reinforcing the relationship.

  • 23.
    Croy, Ilona
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Technical University of Dresden, Germany.
    Geide, Helen
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Medicinska fakulteten. Linköpings universitet, Centrum för social och affektiv neurovetenskap (CSAN).
    Paulus, Martin
    Laureate Institute Brain Research, OK USA.
    Weidner, Kerstin
    Technical University of Dresden, Germany.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten.
    Affective touch awareness in mental health and disease relates to autistic traits - An explorative neurophysiological investigation2016Ingår i: Psychiatry Research, ISSN 0165-1781, E-ISSN 1872-7123, Vol. 245, s. 491-496Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Affective touch is important for social interaction within families and groups and there is evidence that unmyelinated C tactile fibers are involved in this process. Individuals with autism spectrum disorders show alterations in the perception and processing of affective touch. sThus, we hypothesized that affective touch awareness based on C tactile fiber activation is impaired in individuals with high levels of autistic trait. The pleasantness perception of optimal and suboptimal C tactile stimuli was tested in an explorative study in 70 patients recruited from an outpatient psychotherapy clinic and 69 healthy comparison subjects. All participants completed questionnaires about autistic traits, depressive symptomatology, childhood maltreatment, and about the daily amount of touch. Relative to comparison subjects, patients reported engaging in touch less frequently in daily life and rated touch less pleasant. Reduced valence ratings of touch were explained by childhood maltreatment but not by any particular disorder or depression severity. Among all tested variables, the affective touch awareness correlated with autistic traits only - in patients as well as in comparison subjects. Taken together, individuals with mental health issues have a lower baseline of expression and reception of affective touch. Autistic traits and childhood maltreatment modulate the experience of affective touch. (C) 2016 Elsevier Ireland Ltd. All rights reserved.

  • 24.
    Case, Laura K.
    et al.
    NIH, MD 20892 USA.
    Laubacher, Claire M.
    NIH, MD 20892 USA.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten.
    Wang, Binquan
    NIH, MD 20892 USA.
    Spagnolo, Primavera A.
    NIAAA, MD 20892 USA.
    Catherine Bushnell, M.
    NIH, MD 20892 USA.
    Encoding of Touch Intensity But Not Pleasantness in Human Primary Somatosensory Cortex2016Ingår i: Journal of Neuroscience, ISSN 0270-6474, E-ISSN 1529-2401, Vol. 36, nr 21, s. 5850-5860Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Growing interest in affective touch has delineated a neural network that bypasses primary somatosensory cortex (S1). Several recent studies, however, have cast doubt on the segregation of touch discrimination and affect, suggesting that S1 also encodes affective qualities. We used functional magnetic resonance imaging (fMRI) and repetitive transcranial magnetic stimulation (rTMS) to examine the role of S1 in processing touch intensity and pleasantness. Twenty-six healthy human adults rated brushing on the hand during fMRI. Intensity ratings significantly predicted activation in S1, whereas pleasantness ratings predicted activation only in the anterior cingulate cortex. Nineteen subjects also received inhibitory rTMS over right hemisphere S1 and the vertex (control). After S1 rTMS, but not after vertex rTMS, sensory discrimination was reduced and subjects with reduced sensory discrimination rated touch as more intense. In contrast, rTMS did not alter ratings of touch pleasantness. Our findings support divergent neural processing of touch intensity and pleasantness, with affective touch encoded outside of S1.

  • 25.
    Sehlstedt, Isac
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Medicinska fakulteten. University of Gothenburg, Sweden.
    Ignell, Hanna
    University of Gothenburg, Sweden.
    Backlund Wasling, Helena
    University of Gothenburg, Sweden.
    Ackerley, Rochelle
    University of Gothenburg, Sweden.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten.
    Croy, Ilona
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Technical University of Dresden, Germany.
    Gentle Touch Perception Across the Lifespan2016Ingår i: Psychology and Aging, ISSN 0882-7974, E-ISSN 1939-1498, Vol. 31, nr 2, s. 176-184Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Pleasant, affective touch provides various health benefits, including stress and depression relief. There is a dichotomy between mechanoreceptive afferents that predominantly signal discriminative (myelinated A-beta) and affective (unmyelinated C-tactile) aspects of touch. It is well documented that discriminative abilities of touch decline with age. However, a thorough investigation of how the pleasant aspects of touch develop with age has not been previously attempted. Here, we investigated the relationship between age and psychophysical ratings in response to gentle stroking touch. One hundred twenty participants (60 males, 60 females) ages 13-82 years were presented with C-tactile optimal and suboptimal stroking velocities, and rated pleasantness and intensity. Moreover, to examine the specificity of age effects on touch perception, we used olfactory stimuli as a cross-sensory comparison. For all ages, we found that C-tactile optimal stimuli were rated significantly more pleasant than C-tactile suboptimal stimuli. Although, both touch and olfactory intensity ratings were negatively correlated with age, a positive correlation between pleasantness ratings of touch (but not olfactory stimuli) and age was found. We conclude that the affective, but not the discriminative, aspects of touch are enhanced with increasing age. The increase of pleasantness of all touch stimuli in late adulthood is discussed in relation to cognitive modulations.

  • 26.
    Croy, Ilona
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Technical University of Dresden, Germany.
    Luong, A.
    Sahlgrens University Hospital, Sweden.
    Triscoli, C.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Medicinska fakulteten. Linköpings universitet, Centrum för social och affektiv neurovetenskap (CSAN). Sahlgrens University Hospital, Sweden.
    Hofmann, E.
    Technical University of Dresden, Germany.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten.
    Sailer, U.
    University of Gothenburg, Sweden.
    Interpersonal stroking touch is targeted to C tactile afferent activation2016Ingår i: Behavioural Brain Research, ISSN 0166-4328, E-ISSN 1872-7549, Vol. 297, s. 37-40Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    C tactile fibers are a specialized group of fibers innervating the non-glabrous skin that are tuned to light gentle stroking applied with velocities between 1 and 10 cm/s. Those fibers add to the sensation of interpersonal caressing and pleasant touch. It is unclear whether people spontaneously apply touch that is tuned to optimally activate those fibers. This was investigated in three studies. In study one, 45 participants (21.8 +/- 2.3 years, 24 women) were asked to stroke an artificial arm. In study two, 32 participants (28.3 +/- 8.7years, 16 women) were asked to stroke their partner. In study three, 11 parents (29.4 +/- 5.7years, 6 women) were asked to stroke their babies. Stroking velocity was tracked in all conditions. Stroking velocities were significantly slower in the partner touch and baby touch condition than in the artificial arm condition and all of the participants stroking their partner or baby used velocities that can activate C tactile fibers. We conclude that human social stroking is optimized for C tactile stimulation. (C) 2015 Elsevier B.V. All rights reserved.

  • 27.
    Croy, Ilona
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. University of Gothenburg, Sweden; Technical University of Dresden, Germany.
    Drechsler, Edda
    Technical University of Dresden, Germany.
    Hamilton, Paul
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Linköpings universitet, Centrum för social och affektiv neurovetenskap (CSAN).
    Hummel, Thomas
    Technical University of Dresden, Germany.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. University of Gothenburg, Sweden.
    Olfactory modulation of affective touch processing - A neurophysiological investigation2016Ingår i: NeuroImage, ISSN 1053-8119, E-ISSN 1095-9572, Vol. 135, s. 135-141Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Touch can be highly emotional, and depending on the environment, it can be perceived as pleasant and comforting or disgusting and dangerous. Here, we studied the impact of context on the processing of tactile stimuli using a functional magnetic resonance imaging (fMRI) paradigm. This was achieved by embedding tactile stimulation in a variable olfactory environment. Twenty people were scanned with BOLD fMRI while receiving the following stimulus blocks: Slow stroking Touch, Civette odor (feces like), Rose odor, Touch + Civette, and Touch + Rose. Ratings of pleasantness and intensity of tactile stimuli and ratings of disgust and intensity of olfactory stimuli were collected. The impact of the olfactory context on the processing of touch was studied using covariance analyses. Coupling between olfactory processing and somatosensory processing areas was assessed with psychophysiological interaction analysis (PPI). A subjectively disgusting olfactory environment significantly reduced the perceived pleasantness of touch. The touch fMRI activation in the secondary somatosensory cortex, operculum 1 (OP1), was positively correlated with the disgust towards the odors. Decreased pleasantness of touch was related to decreased posterior insula activity. PPI analysis revealed a significant interaction between the OP1, posterior insula, and regions processing the disgust of odors (orbitofrontal cortex and amygdala). We conclude that the disgust evaluation of the olfactory environment moderates neural reactivity in somatosensory regions by upregulation of the OP1 and downregulation of the posterior insula. This adaptive regulation of affective touch processing may facilitate adaptive reaction to a potentially harmful stimulus. (C) 2016 Elsevier Inc. All rights reserved.

  • 28.
    Davidovic, Monika
    et al.
    University of Gothenburg, Sweden.
    Jonsson, Emma H.
    University of Gothenburg, Sweden.
    Olausson, Håkan
    Linköpings universitet, Centrum för social och affektiv neurovetenskap (CSAN). Linköpings universitet, Medicinska fakulteten. Linköpings universitet, Institutionen för klinisk och experimentell medicin.
    Björnsdotter Åberg, Malin
    Linköpings universitet, Centrum för social och affektiv neurovetenskap (CSAN). Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. University of Gothenburg, Sweden.
    Posterior Superior Temporal Sulcus Responses Predict Perceived Pleasantness of Skin Stroking2016Ingår i: Frontiers in Human Neuroscience, ISSN 1662-5161, E-ISSN 1662-5161, Vol. 10, nr 432Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Love and affection is expressed through a range of physically intimate gestures, including caresses. Recent studies suggest that posterior temporal lobe areas typically associated with visual processing of social cues also respond to interpersonal touch. Here, we asked whether these areas are selective to caress-like skin stroking. We collected functional magnetic resonance imaging data from 23 healthy participants and compared brain responses to skin stroking and vibration. We did not find any significant differences between stroking and vibration in the posterior temporal lobe; however, right posterior superior temporal sulcus (pSTS) responses predicted healthy participants perceived pleasantness of skin stroking, but not vibration. These findings link right pSTS responses to individual variability in perceived pleasantness of caress-like tactile stimuli. We speculate that the right pSTS may play a role in the translation of tactile stimuli into positively valenced, socially relevant interpersonal touch and that this system may be affected in disorders associated with impaired attachment.

  • 29.
    Sailer, Uta
    et al.
    University of Gothenburg, Sweden; University of Oslo, Norway.
    Triscoli, Chantal
    University of Gothenburg, Sweden; Sahlgrens University Hospital, Sweden.
    Haggblad, Gisela
    Gothenburg University, Sweden.
    Hamilton, Paul
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Linköpings universitet, Centrum för social och affektiv neurovetenskap (CSAN).
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Sahlgrens University Hospital, Sweden.
    Croy, Ilona
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Technical University of Dresden, Germany.
    Temporal dynamics of brain activation during 40 minutes of pleasant touch2016Ingår i: NeuroImage, ISSN 1053-8119, E-ISSN 1095-9572, Vol. 139, s. 360-367Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Introduction: Touch is important for individuals subjective well-being, is typically rewarding, and is one of few sensory stimuli which are experienced as pleasant for a rather long time. This study tracked brain activation during slow stroking stimulation of the arm that was applied continuously for 40 min - a much longer time than what previous studies have investigated. Methods: 25 subjects were stroked for 40 min with a soft brush while they were scanned with functional Magnetic Resonance Imaging, and rated the perceived pleasantness of the brush stroking. Two resting baselines were included. Whole brain-based analyses investigated the neural response to long-lasting stroking. Results: Stroking was perceived as pleasant throughout scanning and activated areas that were previously found to be involved in the processing of pleasant touch. Activation in primary somatosensory cortex (S1) and S2, subdivision OP1, decreased over time, whereas activation in orbito-frontal gyrus (OFC) and putamen strongly increased until reaching a plateau after approximately 20 min. Similarly, functional connectivity of posterior insula with middle cingulate and striatal regions increased over time. Discussion: Long-lasting stroking was processed in similar areas as shorter-lasting stroking. The decreased activation in somatosensory cortices over time may represent stimulus habituation, whereas increased activation in OFC and putamen may relate to the stimulations subjective reward value. This involvement of reward-related brain circuits can facilitate maintenance of long-lasting social touch interactions. (C) 2016 The Authors. Published by Elsevier Inc.

  • 30.
    Ellingsen, Dan-Mikael
    et al.
    Harvard University, MA 02215 USA; University of Oslo, Norway.
    Leknes, Siri
    University of Oslo, Norway.
    Loseth, Guro
    University of Oslo, Norway.
    Wessberg, Johan
    University of Gothenburg, Sweden.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten.
    The Neurobiology Shaping Affective Touch: Expectation, Motivation, and Meaning in the Multisensory Context2016Ingår i: Frontiers in Psychology, ISSN 1664-1078, E-ISSN 1664-1078, Vol. 6, nr 1986Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Inter individual touch can be a desirable reward that can both relieve negative affect and evoke strong feelings of pleasure. However, if other sensory cues indicate it is undesirable to interact with the toucher, the affective experience of the same touch may be flipped to disgust. While a broad literature has addressed, on one hand the neurophysiological basis of ascending touch pathways, and on the other hand the central neurochemistry involved in touch behaviors, investigations of how external context and internal state shapes the hedonic value of touch have only recently emerged. Here, we review the psychological and neurobiological mechanisms responsible for the integration of tactile "bottom-up" stimuli and "top-down" information into affective touch experiences. We highlight the reciprocal influences between gentle touch and contextual information, and consider how, and at which levels of neural processing, top down influences may modulate ascending touch signals. Finally, we discuss the central neurochemistry, specifically the mu-opioids and oxytocin systems, involved in affective touch processing, and how the functions of these neurotransmitters largely depend on the context and motivational state of the individual.

  • 31.
    Case, Laura K
    et al.
    National Center for Complementary and Integrative Health, NIH , Bethesda, Maryland 20892, USA.
    Čeko, Marta
    National Center for Complementary and Integrative Health, NIH , Bethesda, Maryland 20892, USA.
    Gracely, John L
    National Center for Complementary and Integrative Health, NIH , Bethesda, Maryland 20892, USA.
    Richards, Emily A
    National Center for Complementary and Integrative Health, NIH , Bethesda, Maryland 20892, USA.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Centrum för social och affektiv neurovetenskap (CSAN). Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurofysiologiska kliniken US.
    Bushnell, M Catherine
    National Center for Complementary and Integrative Health, NIH , Bethesda, Maryland 20892, USA.
    Touch Perception Altered by Chronic Pain and by Opioid Blockade.2016Ingår i: eNeuro, ISSN 2373-2822, Vol. 3, nr 1Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Touch plays a significant role in human social behavior and social communication, and its rewarding nature has been suggested to involve opioids. Opioid blockade in monkeys leads to increased solicitation and receipt of grooming, suggesting heightened enjoyment of touch. We sought to study the role of endogenous opioids in perception of affective touch in healthy adults and in patients with fibromyalgia, a chronic pain condition shown to involve reduced opioid receptor availability. The pleasantness of touch has been linked to the activation of C-tactile fibers, which respond maximally to slow gentle touch and correlate with ratings of pleasantness. We administered naloxone to patients and healthy controls to directly observe the consequences of µ-opioid blockade on the perceived pleasantness and intensity of touch. We found that at baseline chronic pain patients showed a blunted distinction between slow and fast brushing for both intensity and pleasantness, suggesting reduced C-tactile touch processing. In addition, we found a differential effect of opioid blockade on touch perception in healthy subjects and pain patients. In healthy individuals, opioid blockade showed a trend toward increased ratings of touch pleasantness, while in chronic pain patients it significantly decreased ratings of touch intensity. Further, in healthy individuals, naloxone-induced increase in touch pleasantness was associated with naloxone-induced decreased preference for slow touch, suggesting a possible effect of opioid levels on processing of C-tactile fiber input. These findings suggest a role for endogenous opioids in touch processing, and provide further evidence for altered opioid functioning in chronic pain patients.

  • 32.
    Lee, In-Seon
    et al.
    Kyung Hee University, South Korea; University of Tubingen, Germany; University of Tubingen, Germany; University of Tubingen, Germany.
    Lee, Bombi
    Kyung Hee University, South Korea.
    Park, Hi-Joon
    Kyung Hee University, South Korea.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurofysiologiska kliniken US.
    Enck, Paul
    University of Tubingen, Germany.
    Chae, Younbyoung
    Kyung Hee University, South Korea.
    A new animal model of placebo analgesia: involvement of the dopaminergic system in reward learning2015Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, nr 17140Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We suggest a new placebo analgesia animal model and investigated the role of the dopamine and opioid systems in placebo analgesia. Before and after the conditioning, we conducted a conditioned place preference (CPP) test to measure preferences for the cues (Rooms 1 and 2), and a hot plate test (HPT) to measure the pain responses to high level-pain after the cues. In addition, we quantified the expression of tyrosine hydroxylase (TH) in the ventral tegmental area (VTA) and c-Fos in the anterior cingulate cortex (ACC) as a response to reward learning and pain response. We found an enhanced preference for the low level-pain paired cue and enhanced TH expression in the VTA of the Placebo and Placebo + Naloxone groups. Haloperidol, a dopamine antagonist, blocked these effects in the Placebo + Haloperidol group. An increased pain threshold to high-heat pain and reduced c-Fos expression in the ACC were observed in the Placebo group only. Haloperidol blocked the place preference effect, and naloxone and haloperidol blocked the placebo analgesia. Cue preference is mediated by reward learning via the dopamine system, whereas the expression of placebo analgesia is mediated by the dopamine and opioid systems.

  • 33.
    Ackerley, R
    et al.
    Institute of Neuroscience and Physiology, University of Gothenburg, Sweden / SDS Clinic, ESRS accredited Sleep Research Laboratory, Gothenburg, Sweden.
    Badre, G
    Institute of Neuroscience and Physiology, University of Gothenburg, Sweden / SDS Clinic, ESRS accredited Sleep Research Laboratory, Gothenburg, Sweden.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Institute of Neuroscience and Physiology, University of Gothenburg, Sweden / SDS Clinic, ESRS accredited Sleep Research Laboratory, Gothenburg, Sweden.
    Positive Effects of a Weighted Blanket on Insomnia2015Ingår i: Journal of Sleep Medicine & Disorders, ISSN 2379-0822, Vol. 2, nr 3, s. 1-7Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Insomnia is a common occurrence and can have a negative impact on physiological, psychological and social well-being. There is a need for simple, effective solutions to increase sleep quality. It has been suggested that weighted blankets and vests can provide a beneficial calming effect, especially in clinical disorders. Hence, we aimed to investigate the effects of a chain weighted blanket on insomnia, using objective and subjective measures. Objectively, we found that sleep bout time increased, as well as a decrease in movements of the participants, during weighted blanket use. Subjectively, the participants liked sleeping with the blanket, found it easier to settle down to sleep and had an improved sleep, where they felt more refreshed in the morning. Overall, we found that when the participants used the weighted blanket, they had a calmer night’s sleep. A weighted blanket may aid in reducing insomnia through altered tactile inputs, thus may provide an innovative, non-pharmacological approach and complementary tool to improve sleep quality.

  • 34.
    Perini, Irene
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten.
    Morrison, India
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurofysiologiska kliniken US.
    Seeking pleasant touch: neural correlates of behavioral preferences for skin stroking2015Ingår i: Frontiers in Behavioral Neuroscience, ISSN 1662-5153, E-ISSN 1662-5153, Vol. 9, nr 8Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Affective touch is a dynamic process. In this fMRI study we investigated affective touch by exploring its effects on overt behavior. Arm and palm skin were stroked with a soft brush at five different velocities (0.3, 1, 10, 3, and 30 cm s(-1)), using a novel feedback-based paradigm. Following stimulation in each trial, participants actively chose whether the caress they would receive in the next trial would be the same speed ("repeat") or different ("change"). Since preferred stroking speeds should be sought with greater frequency than non-preferred speeds, this paradigm provided a measure of such preferences in the form of active choices. The stimulation velocities were implemented with respect to the differential subjective pleasantness ratings they elicit in healthy subjects, with intermediate velocities (1, 10, and 3 cm s(-1)) considered more pleasant than very slow or very fast ones. Such pleasantness ratings linearly correlate with changes in mean firing rates of unmyelinated low-threshold C-tactile (CT) afferent nerves in the skin. Here, gentle, dynamic stimulation optimal for activating CT-afferents not only affected behavioral choices, but engaged brain regions involved in reward-related behavior and decision-making. This was the case for both hairy skin of the arm, where CTs are abundant, and glabrous skin of the palm, where CTs are absent. These findings provide insights on central and behavioral mechanisms underlying the perception of affective touch, and indicate that seeking affective touch involves value-based neural processing that is ultimately reflected in behavioral preferences.

  • 35.
    Joensson, Emma H.
    et al.
    University of Gothenburg, Sweden.
    Backlund Wasling, Helena
    University of Gothenburg, Sweden.
    Wagnbeck, Vicktoria
    University of Gothenburg, Sweden.
    Dimitriadis, Menelaos
    University of Medical Centre Groningen, Netherlands.
    Georgiadis, Janniko R.
    University of Medical Centre Groningen, Netherlands.
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurofysiologiska kliniken US.
    Croy, Ilona
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Technical University of Dresden, Germany.
    Unmyelinated Tactile Cutaneous Nerves Signal Erotic Sensations2015Ingår i: Journal of Sexual Medicine, ISSN 1743-6095, E-ISSN 1743-6109, Vol. 12, nr 6, s. 1338-1345Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Introduction. Intrapersonal touch is a powerful tool for communicating emotions and can among many things evoke feelings of eroticism and sexual arousal. The peripheral neural mechanisms of erotic touch signaling have been less studied. C tactile afferents (unmyelinated low-threshold mechanoreceptors), known to underpin pleasant aspects of touch processing, have been posited to play an important role. MethodIn two studies, we investigated the relationship between C tactile activation and the perception of erotic and pleasant touch, using tactile brushing stimulation. In total, 66 healthy subjects (37 women, age range 19-51 years) were examined. In study 1 (n=20), five different stroking velocities were applied to the forearm and the inner thigh. The participants answered questions about partnership, mood, and touch. In study 2 (n=46), the same five stroking velocities were applied to the forearm. The participants answered questions about partnership, touch, and sexuality. ResultsBoth touch eroticism and pleasantness were rated significantly higher for C tactile optimal velocities compared with suboptimal velocities. No difference was found between the ratings of the thigh and the forearm. The velocity-dependent rating curves of pleasantness, intensity, and eroticism differed from each other. Pleasantness was best explained by a quadratic fit, intensity by a linear fit, and eroticism by both. A linear transformation of pleasantness and intensity predicted the observed eroticism ratings reliably. Eroticism ratings were negatively correlated with length of relationship. ConclusionTouch was rated most erotic when perceived as pleasant and weak. In human hairy skin, perception of pleasantness is correlated with the firing rate of C tactile afferents, and perception of intensity is correlated with the firing rate of A afferents. Accordingly, eroticism may be perceived most readily for touch stimuli that induce high activity in C tactile fibers and low activity in A fibers. Jonsson EH, Backlund Wasling H, Wagnbeck V, Dimitriadis M, Georgiadis JR, Olausson H, and Croy I. Unmyelinated tactile cutaneous nerves signal erotic sensations. J Sex Med 2015;12:1338-1345.

  • 36.
    McGlone, Francis
    et al.
    Liverpool John Moores University, England University of Liverpool, England .
    Wessberg, Johan
    University of Gothenburg, Sweden .
    Olausson, Håkan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurofysiologiska kliniken US.
    Discriminative and Affective Touch: Sensing and Feeling2014Ingår i: Neuron, ISSN 0896-6273, E-ISSN 1097-4199, Vol. 82, nr 4, s. 737-755Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    The multimodal properties of the human somatosensory system continue to be unravelled. There is mounting evidence that one of these submodalities-touch-has another dimension, providing not only its well-recognized discriminative input to the brain, but also an affective input. It has long been recognized that touch plays an important role in many forms of social communication and a number of theories have been proposed to explain observations and beliefs about the "power of touch." Here, we propose that a class of low-threshold mechanosensitive C fibers that innervate the hairy skin represent the neurobiological substrate for the affective and rewarding properties of touch.

1 - 36 av 36
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf