Center for Neural Science and Medicine, Cedars-Sinai Medical Center
Division of Biology and Biological Engineering, California Institute of Technology
Probing human memory at the single-neuron level
Memories are central to cognition and define each of us as an individual. We are utilizing extracellular recordings in humans undergoing neurosurgical procedures and computational models to study the mechanisms of human memory, decision making, and control. I will describe different functional cell types in the human medial temporal and frontal lobe that together form building blocks for declarative memory. Visually selective neurons are tuned to high-level semantic concepts, are sensitive to attention, predict awareness, and form attractors through persistent activity. Memory-selective neurons, on the other hand, signal whether a stimulus is familiar, predict declared retrieval confidence, but are not memory-content tuned. I will further discuss our work on how memories are translated into decisions. In medial frontal cortex, memory-based choice cells selectively signal choices that depended on memory and transiently phase-lock to hippocampal theta. This information-routing is controlled in a task-demand dependent manner: memory-related information is only represented in frontal cortex when choices require it. This work reveals single-cell correlates and their oscillation-mediated interactions of key aspects of human memory. These findings suggest specific interventions for potential new approaches towards treatments for memory disorders.
A pizza lunch will be served at 11:45am. The seminar will run from 12:00pm – 1:30pm.