Guy Bouvier (Scanziani Lab, University of California, San Francisco) has been invited by Serge Charpakto hold a talk on Friday 13 May, 3 p.m. , in the conference room of the UCL , 13 Rue Moreau.

This talk will be on "Correcting for self: The impact of head motion on primary visual cortex activity"

An organism’s survival depends on accurately perceiving and interpreting the environment. A significant part of our visual input is however generated by our own actions, rather than external events. For example, the retina can experience similar visual stimulus driven by head-movement, or by a moving object. Therefore, self-motion related information is fundamental to contextualize visual stimuli. In mammals, the vestibular system reports head movements. Signals from the vestibular organs are broadcasted throughout the brain, including primary sensory regions such as the primary visual cortex (V1).

However, very little is known about how it impacts V1 neuronal activity, how this signal is encoded in V1, and what the upstream sources of vestibular signals are. In this talk, I will show that somatostatin-expressing (SOM) inhibitory neurons regulate V1 neurons activity during head movement, in the absence of visual stimuli. In addition, we will see that V1 neurons encode a complex representation of head movements. Finally, in contrast to the classical feed-forward visual pathway, from the dorsal lateral geniculate thalamic nucleus, I have evidences suggesting that V1 receives head movement signal through other sources. We discovered that the ipsilateral lateral posterior thalamus and the contralateral visual cortex are key sources of vestibular input to V1. Altogether, I will reveal how head movements modulate V1 neurons activity and show a direction specific recruitment of intra- and inter-hemispheric sources of vestibular signals to V1.