A neural marker of medical visual expertise: implications for training

Researchers have identified a component of the EEG that discriminates visual experts from novices. The marker indexes a comprehensive model of visual processing, and if it is apparent in physicians, it could be used to investigate the development and training of their visual expertise. The purpose of this study was to determine whether a neural marker of visual expertise-the enhanced N170 event-related potential-is apparent in the EEGs of physicians as they interpret diagnostic images. We conducted a controlled trial with 10 cardiologists and 9 pulmonologists. Each participant completed 520 trials of a standard visual processing task involving the rapid evaluation of EKGs and CXRs-indicating-lung-disease. Ostensibly, each participant is expert with one type of image and competent with the other. We collected behavioral data on the participants' expertise with EKGs and CXRs and electrophysiological data on the magnitude, latency, and scalp location of their N170 ERPs as they interpreted the two types of images. Cardiologists demonstrated significantly more expertise with EKGs than CXRs, and this was reflected in an increased amplitude of their N170 ERPs while reading EKGs compared to CXRs. Pulmonologists demonstrated equal expertise with both types of images, and this was reflected in equal N170 ERP amplitudes for EKGs and CXRs. The results suggest provisionally that visual expertise has a similar substrate in medical practice as it does in other domains that have been studied extensively. This provides support for applying a sophisticated body of literature to questions about training and assessment of visual expertise among physicians.