Research Meeting: "Probing the mechanisms of visual object recognition with reversible chemogenetic modulation of macaque V4 neurons" by Dr. Kohitij Kar

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February 15, 2022 - 4:00 pm to 5:30 pm
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Dr. Kohitij Kar, DiCarlo Lab, MIT


The Spring 2022 CBMM Research Meetings will be hosted in a hybrid format. Please see the information included below regarding attending the event either in-person or remotely via Zoom connection

Please note, MIT is requiring that all attendees, including MIT COVIDpass users, sign-in to the event prior to entering the auditorium.

Abstract: We can computationally approximate a visual object's identity from the distributed neural activity patterns across a series of hierarchically connected brain areas (e.g., V4, IT) in the primate ventral stream. However, testing whether these circuits indeed play a causal role requires targeted neural perturbation strategies that enable discrimination amongst competing models. Here we probed the role of macaque V4 and its primary feedforward target, the inferior temporal (IT) cortex, during object recognition. We combined DREADDs-based chemogenetic inhibition of V4 neurons with large-scale electrophysiology in V4 and IT while simultaneously measuring the monkeys' image-by-image object recognition behavior. Our results provide causal evidence linking the ventral stream hierarchy with core object recognition behavior. Also, in addition, to providing a “yes” vs. “no” answer to the involvement of a brain area in a behavior, we demonstrate how our approach allows us to use direct causal perturbation data to discriminate amongst competing mechanistic brain models.​


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MIT Building 46 | Brain and Cognitive Sciences Complex
February 15, 2022
4:00 pm to 5:30 pm
MIBR Seminar Room 46-3189

MIT Building 46 | Brain and Cognitive Sciences Complex, 43 Vassar Street, Cambridge MA 02139