Good working memory capacity facilitates long-term memory encoding of speech in stationary noise
2015 (English)Conference paper, Abstract (Refereed)
Background noise makes listening more cognitively demanding, especially for persons with hearingimpairment, and this seems to aect memory encoding. It is not clear whether this decrement can berestored by providing visual cues. In the present study, we investigated whether long term memoryencoding of speech, in quiet and in background noise adjusted to retain intelligibility, improves whenthe talkers face is visible, and whether such an enhancement is associated with working memorycapacity. Twenty adults with normal hearing in Experiment 1 and 24 adults with hearing loss inExperiment 2 listened to lists of 13 two-digit numbers, with or without seeing the talkers face, andthen recalled as many numbers as possible in any order. The lists were presented in quiet as wellin a steady-state speech-weighted noise and the International Speech Testing Signal at a signal-tonoiseratio individually adapted to give an intelligibility level of approximately 90%. Amplicationcompensated for loss of audibility. Working memory capacity was measured using the reading spantest. Seeing the talkers face did enhance free recall performance. However, whereas the eect size foradults with normal hearing was large, for adults with hearing impairment it was small. Further, therewas no evidence that visual cues specically compensated for performance decrements due to noiseor serial position and there was no evidence of an association between working memory capacity andperformance with visual cues. However, good working memory capacity did improve performance forearly list items, reecting facilitation of long-term memory encoding, for both groups when stimuliwere presented in steady-state noise. For participants with hearing impairment, good working memorycapacity was associated with good performance on late list items in quiet, reecting facilitationof working memory encoding. This pattern of results indicates that steady-state background noisereduces the cognitive capacity available for the long-term memory encoding of speech that is necessaryfor enduring retention of spoken information, irrespective of hearing status, but provides no evidencethat this is specically compensated for by visual cues. It also demonstrates that for individuals withhearing impairment, short term retention of speech heard even under the most favourable conditionsis a function of individual working memory capacity. These ndings support and extend the Ease ofLanguage Understanding Model.
Place, publisher, year, edition, pages
Other Social Sciences
IdentifiersURN: urn:nbn:se:liu:diva-115095OAI: oai:DiVA.org:liu-115095DiVA: diva2:793572
7th Speech in Noise Workshop, Copenhamn, Denmark, 8-9 January 2015