Methods: Fourteen students (3 males, 12 females; ages 23Y28 years) from Eastern
VirginiaMedical School’sMaster of Surgical Assisting Program participated in this IRB
approved study. Participants practiced the peg transfer task from the FLS curriculum on
a box simulator for 20Y30 minutes over 9Y15 weekly sessions. Their course schedule
required all students to stop training after the 15th week irrespective of their performance
level. They returned after a 1-month interval to resume training. The dependent
measure was task completion time. The secondary task presented images of four balls in
a simulated tunnel, superimposed at 50% transparency over the laparoscopic display so
that both tasks were in focal vision. Images were presented for 300 msec every 2Y4 sec.
On half of the presentations, one ball changed its position. Participants had to detect
those changes by pressing a foot pedal. The dependent variables were the proportion of
correctly identified targets and false alarms.
Hypothesis: Performing laparoscopy places heavy demands on visual attention and
requires extensive practice to achieve proficiency. Recently, some researchers have
measured the mental workload imposed by laparoscopy using the secondary task
technique.1,2 According to multiple resource theory, pools of attentional resources are
distinguished by perceptual/cognitive processing stages, verbal and spatial processing
codes, and sensory modality with the vision separated into focal and peripheral
channels.3 Thus, a secondary task that competes for the same resources as a primary
task will cause interference and can be sensitive to differences in mental workload. In
this study,mental workload was assessed with a secondary task that uses the same visual
spatial resources as laparoscopy.We studied effects of refraining from practice during a
1-month interval. We expected to see a decline in performance after the delay, but our
goal was to see if decline would be present in the workload measure.
Results: Three sets of tests were performed: the data for the last two training trials (N
and N-1), the last training trial (N) and the initial retention test after the delay interval,
and the initial retention test vs. a final test after 30 minutes of retraining (see Table 1).
All means were evaluated with dependent t tests (alpha = .05). There were no differences
between the last two training trials on any measure. The peg task completion
times were significantly longer on the initial test compared to the last training trial,
t(13) = 2.36, p G .05. There were no differences between the initial and final test on any
measure (p 9 .05).
Conclusion: The results show minimal effects on the peg transfer task from the FLS
program over a 1-month retention interval. Mean completion times were significantly
longer after the delay interval, but only by 6 seconds (or less than 10%). There were no
significant differences on the secondary task. Thus, the slower performance times were
not accompanied by any appreciable changes in mental workload. These results show
that 9 Y 15 training sessions were sufficient to establish robust skills for the peg transfer
task and that these skills were fairly resilient to a moderate disruption in the training
schedule. Further, the secondary task used in this study was shown to provide an alternative
index of laparoscopic workload that can complement traditional metrics of
speed and accuracy. Future research is needed to examine disruption effects over a
wider range of laparoscopic tasks and longer intervals.