Myriam Hamon: Cortical and Collicular Role in Multimodal Self-initiated Sequential Behaviors

Abstract

Navigation to achieve a goal --to forage and explore the world -- is one of the most basic, and routine acts in the daily lives of people and animals. This action has many complex dimensions: it requires orienting to the environment, while predicting the effect of the movement. The colliculus is thought to control orienting behaviors. Here we trained head-fixed mice in self-initiated behavior that engages multiple sensory motor modalities, as mice plan, decide and execute whisker, eye, and body movements during navigation in a “real-world” maze. Here we examined whether the plan to move can be revealed in the activity of cortical and collicular neurons, whether individual neuron activity is related to a single dimension in behavior or is related to a sequence of related behaviors. Our recordings in the superior colliculus and motor cortex (M2) reveal that in both areas neurons are best related to a single dimension of behavior eye movement, or turning or onset of backward movement. Activating inhibitory neurons in colliculus unilaterally generated contraversive eye, body and whisker movement and triggered activity and suppression in contralateral colliculus. Our work suggests that even though both M2 and colliculus contain a sensory motor map that encompasses the entire spectrum of planning, and movement of the entire body, individual neurons are tuned to single class of movements.

 

Additional information:

Master thesis defense

 

Organized by:

Dr. Jens Kremkow & Dr. Robert Sachdev