The Neural Circuits Underlying Short-term Memory

Abstract

Our goal is to uncover the principles by which cortical circuits perform fundamental computations, from perception to action. Cortex is parcellated into areas with distinct function and local circuits. Cortical areas associate into mesoscale circuits with other cortical and subcortical areas via long-range connections. Information is represented by action potentials in widely distributed ensembles of neurons. What are the mechanisms shaping these neural representations, and how do the representations drive behavior? We have begun to address both questions in behaving mice in the context of motor planning and short-term memory.

Motor planning plays key roles in decision-making and motor control. Apart from reflexes, movements are dynamically programmed to achieve a specific goal. Many movements are too rapid for online corrections. Movements that are preceded by periods of motor planning are faster and more accurate than in the absence of planning. Motor planning is also a prospective form of short-term memory that links past events and future movements. During motor planning, neurons in motor cortex show persistent activity related to specific movements, long before movement onset, in the absence of sensory input. I will present our studies on how neural circuits maintain this selective persistent activity and how this activity relates to future behavior.