Dear Colleagues,

Professor Reiko Graham from Texas State University (https://www.psych.txstate.edu/faculty/psydirectory/Reiko-Graham.html) will be presenting on her work on Friday April 8, 2022, from 11.30am-12.30pm. Professor Graham is visiting McGill on her sabbatical.

Talk Title: Can I eat this? Event-related potentials are modulated by feedback regarding edibility

Abstract: Not all mistakes are created equal, and the consequences of errors vary widely. To examine the neural correlates of error magnitude, paradigms using extrinsic rewards and punishments (e.g. monetary gains and losses) are often used. We endeavored to create a task that tapped into intrinsic motivations by asking participants to make judgments about the edibility of ambiguous objects, which was then followed by feedback. We reasoned that edibility judgments would engage evaluative processes associated with potential oral incorporation, such that incorrectly stating that an inedible object was edible would be considered a more serious error (violating the body boundary) than the opposite. Twenty-five undergraduates (15 male, mean age = 21.5 years) viewed close-ups of food/drinks or nonfood/drinks, and indicated whether they could consume the objects. Feedback about stimulus type (unambiguous, zoomed-out images) was then provided. Analyses focused on ERPs to feedback trials; specifically, an earlier frontocentral negativity (feedback-related negativity or FRN) that is sensitive to reward and error magnitude and the centroparietally-distributed P300 that is sensitive to motivationally relevant stimuli. In line with our expectations, a stimulus type by outcome interaction was observed for the FRN, such that amplitude was largest when participants incorrectly identified nonfoods as foods, suggesting that this error was more significant than incorrectly identifying foods as nonfoods. The P300 was also sensitive to feedback, and amplitudes were highest when participants correctly identified foods. These results provide support for the hypothesis that the FRN is an index of error magnitude. Additionally, the enhanced P300 amplitudes to correct feedback regarding food items may index the salience and reinforcing properties of making correct judgments regarding edibility.

ZOOM Link: https://mcgill.zoom.us/j/84653117031

I hope many of you can join us for this event!

Please excuse for cross posting and feel free to advertise to your colleagues and research groups.

Best,

Jelena Ristic

------------------------------------------ Jelena Ristic, PhD Professor & William Dawson Scholar Department of Psychology, McGill University 1205 Dr. Penfield Avenue, Montreal, QC, H3A 1B1 Phone: 514.398.2091 Email: jelena.ristic@mcgill.camailto:jelena.ristic@mcgill.ca Web: http://www.mcgill.ca/asc