Pathologists aren’t Pigeons: Exploring the neural basis of visual recognition and perceptual expertise in pathology

Abstract

Abstract Visual (perceptual) reasoning is a critical skill to many specialties of medical diagnosis, including pathology, diagnostic imaging, and dermatology. However, in an ever-compressed medical curriculum, learning and practicing this skill is often challenging. Previous studies (including work with pigeons) have suggested that using reward-feedback-based activities, novices can gain expert levels of visual diagnostic accuracy in shortened training times. But is this level of diagnostic accuracy a result of image recognition (categorization) or is it the acquisition of diagnostic expertise? To answer this, we measured electroencephalographic data (EEG) and two components of the human event-related brain potential - the reward positivity and the N170 - to further study the nature of visual expertise in a novice-expert study in pathology. We demonstrate that the amplitude of the reward positivity decreases with learning in novices (suggesting a decrease in reliance on feedback, as in other studies). However, this signal remains significantly different from the experts whose reward positivity signal did not change over the course of the experiment. We further show no change in the amplitude of the N170 - a reported neural marker of visual expertise - in novices over time and that their N170 signals remain statistically and significantly lower than experts throughout task performance. These data suggest that while novices gain the ability to recognize (categorize) pathologies through reinforcement learning, there is little change in the neural marker associated with visual expertise. This is consistent with the multi-dimensional and complex nature of visual expertise and provides insight into future training programs for novices to bridge the expertise gap.