Research Meeting: Towards a mechanistic understanding of compositionality by Lucas Tien

Photo of Dr. Lucas Tian, Rockefeller University
September 28, 2021 - 4:00 pm to 5:30 pm

Dr. Lucas Tian, Rockefeller University


Abstract: Compositionality is a key signature of the mind. It is the ability to generalize from a small set of rules to an almost unlimited set of complex thoughts and behaviors. Compositionality is critical for many domains of intelligence, such as language, social reasoning, and motor planning. Yet we do not understand the neural mechanisms of compositionality. This reflects the gap between two approaches for understanding the mind, one focusing on symbolic computation in complex cognition (cognitive science) and the other focusing on neural processes in simpler forms of cognition in animals (systems neuroscience). To bridge this gap, we have developed a way to study symbol-like compositionality in macaque monkeys, a highly intelligent species that is well-suited for neurophysiological analysis. This approach is based on a compositional drawing task. In this task, macaques draw new complex images by combining a small set of learned components, including (i) motor “primitives” (e.g., line, circle, triangle) and (ii) abstract sequencing rules for combining primitives. I will present behavioral evidence that both humans and macaques exhibit compositionality in how they draw, preliminary neural network modeling of compositional drawing, and plans for large-scale neurophysiology. I expect that combining insights across behavioral, cognitive, and neural levels will lead to new explanations of how compositionality works.

The Fall 2021 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

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MIT Building 46 | Brain and Cognitive Sciences Complex
September 28, 2021
4:00 pm to 5:30 pm
PILM Seminar Room 46-3310