The Effect of Fatigue on Cognitive and Psychomotor Skills of Surgical Residents Kanav Kahol 1,2 , Mark Smith 1 , Stephanie Mayes 1 , Mary Deka 1 , Vikram Deka 1 , John Ferrara 1 , Sethuraman Panchanathan 2 1 Phoenix Integrated Surgical Residency Program, SimET Center Banner Good Samaritan Medical Center, Phoenix Arizona 2 Arizona State University Abstract. Surgical residents are exposed to a significant amount of cognitive load during call. While various efforts have been made to quantify the effect of fatigue and sleep deprivation on the psychomotor skills of surgical residents, there is very little investigations into the effect of these factors on cognitive skills. However, this is an important issue in medical curriculum design, as much of the medical errors are procedural in nature and are not psychomotor. In this paper, we present a study that aimed to quantify the effect of fatigue on cognitive skills. We employed hand movement data for developing a proficiency measure of surgical skill. The difference in proficiencies measured through hand movement post call and pre call was determined. The simulation tasks were designed to challenge working memory, attention of the user. The results showed a significant difference in hand movement proficiencies as well as behavioral errors pre and post-call. EEG Data was also gathered during simulation tasks pre and post call through the B-Alert® Bluetooth EEG technology. The B-Alert® software was analyzed to reveal ratings of alertness/drowsiness, engagement, mental workload and distraction. The results showed statistically significant difference in EEG ratings in pre call and post call condition. 1 Introduction In 1999 the Institute of Medicine published the now famous study “To Err is Human” on the unacceptably high rate of errors in medicine, and that has generated even more demand for changes in the status quo in healthcare. As a result, many of the prevalent approaches in medical field are being questioned. One of the burning questions is the effect of fatigue and sleep deprivation on the skills of residents. Residency programs require medical residents to perform various kinds of medical duties over extended periods of 16-24 hours. These extended hours of operation can significantly influence a doctor’s ability to perform. This factor can be even more critical in surgical procedures that require both cognitive and motor skills. Two decades ago minimally invasive surgery was introduced, and along with it came a more extensive and lengthy learning curve. More complex procedures are being continually developed and introduced, accompanied by more serious risks and complications. These procedures require a significant amount of cognitive as well as psychomotor acuity. It is