How Does the Brain Give Rise to the Mind?
We approach this question by studying how the brain enables us to make intelligent movements. Imagine solving a Rubik’s cube. One has to first gather sensory information based on the configuration of the cube, decide on a plan, keep that information in memory while organizing it into a sequence of actions, then turn those plans into skilled movements. We are interested in understanding how this sequence of events is implemented in the brain.
Motor planning involves activity distributed widely across the cortex. In humans and primates, electrical activity emerges over frontal cortex that predicts an upcoming voluntary movement, even before the subject is aware of their desires to move (a.k.a. “Bereitschaftspotential”). We have developed behavioral paradigms and tools to delineate when and how activity in specific cortical regions drives sensory-guided motor planning in the mouse. We look at the involved neural circuits in the time window of hundreds of milliseconds before the movement. Using genetic tools, 2-photon microscopy and multiple electrode recordings, we study how different types of neurons interact to give rise to the activity patterns preceding the movement. We establish the relationship between specific activity patterns and behavior using perturbations.
We recently identified a premotor cortical region involved in motor planning. Neuron responses in this region predict voluntary movements seconds in advance. New recording and perturbation methods are beginning to reveal the cellular and circuit mechanisms underlying motor planning which, in turn, will shed light on the biophysics of cognition.
We use motor planning as a window into understanding the internal processes that underlie cognition. The act of motor planning taps into multiple aspects of flexible behavior, such as decision making and short-term memory. Perhaps due to the shared neural computation, motor planning disorders are closely interrelated with cognitive dysfunctions.
- Developing quantitative motor planning behaviors
- Interactions between sensory cortex and motor cortex during motor planning
- Circuit analyses of motor cortex during motor planning