Auditory Stress Versus Mental Loading: The Effects On Laparoscopic Motor Skill Performance
Claudius Conrad MD, PhD, Yusuf Konuk, MD, Andrew Warshaw, MD, David Jones, MD, David Rattner, MD, Denise Gee, MD
Massachusetts General Hospital, Boston, MA
PURPOSE OF STUDY
The specific effects of external auditory stress versus internal mental stress in novices of laparoscopy are poorly understood, but play a significant role in clinical practice.
Thirty naïve volunteers were recruited with no hearing or motor handicap. Volunteers were randomized to three simple tasks to be performed on a laparoscopic simulator: SurgicalSIM VR. Tasks were equal in difficulty and performed under three variable conditions: silence, auditory stress (dichaotic music) and mental loading (mental arithmetic tasks). Permutations of the conditions were created in order to account for a learning effect. Tasks were performed twice with a 10 minute break in between to test for memory consolidation and to accommodate baseline variability. Time until task completion and tip trajectory (path of tip through space) were recorded.
SUMMARY OF RESULTS
Auditory stress and mental loading led to an increase in time to task completion when compared to silence (2.3 fold and 2.4 fold, respectively). Each led to a 1.8 and 2.0 fold increase in trajectory. Inter-person variability regarding task performance of the volunteers in response to auditory stress was greater compared to mental loading. In addition mental loading specifically affected recall of the procedure with an improvement accountable to memory consolidation of only 4% versus 32% in silence (p=0.021).
Auditory stress and mental loading lead to prolonged operating time with diminished accuracy. More specifically, mental loading has a negative impact on memory consolidation resulting in lack of recall of learned skills. Further research is necessary to understand the effects of stress on experts and the mechanisms that can be developed to counteract its negative effects on laparoscopic performance.