SCSB Lunch Series: Temporal expectation in marmosets

Date: Friday, February 10, 2023
Time: 12:00pm – 1:00pm
Location: SCSB Conference room 46-6011 + Zoom Meeting (https://mit.zoom.us/j/93895393648)

Speaker: Shreya Mahajan
Affiliation: Mriganka Sur Laboratory, MIT

Host: Dr. Mriganka Sur

Talk title: Temporal expectation in marmosets

Abstract: Temporal expectation is the ability to use information from past events to predict their occurrence in the future, which allows the allocation of appropriate sensory resources in preparation for the event. Problems with time perception have been linked to several behavioral and cognitive impairments in individuals with autism spectrum disorders. We are investigating how the brain acquires temporal expectation, using a marmoset as an animal model. We trained freely behaving marmosets to perform a simple touchscreen-based timing task, and recorded reaction times and intracranial electroencephalogram (EEG) activity from 4 brain regions, as they were trained from a naïve state until they attained expertise. The behavioral change from the naïve state to the expert was well described with a hazard rate model. A trial by trial analysis of EEG data revealed a significant increment in EEG activity corresponding to anticipation of different events during the task, most prominently before reward delivery. These increments also noticeably changed across sessions as the animal acquired the temporal expectation model. Additionally, significant correlations were seen between the reaction times and the activities from the right parietal and the frontal regions during stimulus presentation period. Thus, the acquisition and representation of temporal expectation engages widespread cortical regions, with specific loci representing specific epochs of the task.