November 13, 2025
12:00pm – 1:00pm
Venue
In person event PAB 4-330
“Hierarchical Chunking And Abstraction Of Complex Events In The Primate Brain”
Professor Dun Mao
Institute of Neuroscience
Chinese Academy of Sciences
Shanghai, China
Where: PAB 4-330 on Nov 13 from 12:00-13:00
Humans and animals have an impressive ability to extract knowledge structures, called schemas, and specificdetails from complex real-world events. This skill helps them apply what they learn to different settings and make sense of situations based on the context. We investigated how two brain areas in macaque monkeys?the hippocampus (HPC) and the orbitofrontal cortex (OFC)?team up to break down events during challenging, lifelike tasks. To study this, we designed a unique task where the monkeys navigated in the combination of two kinds of spaces: aphysical one in an open area and an abstract one based on the order of certain cues. Using chronically implanted microdrives, we recorded neuronal activity in HPC and OFC while monitoring the monkeys’ head and gaze stances.The monkeys demonstrated robust behavioral flexibility, achieving a success rate above 75% across events. We found that neurons in both HPC and OFC hierarchically decomposed each event into subgoals and goals, and further showed abstraction across events through dimensionality reduction, aligning with reinforcement learning (RL) principles. In addition, OFC neurons tended to exhibit stronger abstraction across events, while HPC neurons weremore sensitive to event-specific details. These findings reveal how the HPC-OFC in primates encode multidimensional events, offering insights for designing advanced RL algorithms.
Faculty Host: Professor Mayank Mehta
Physics, Neurology, ECE
MayankMehta@ucla.edu