The mammalian neocortex underlies many perceptual, cognitive and affective functions. It also has a layered structure with conserved circuit elements and connectivity but it remains a mystery how this structure leads to function. We will use silicon probes spanning cortical layers combined with optogenetic tagging and manipulation to gather high-resolution data about cell-cell communication in the cortex during various brain states. Gathering fundamental information about cortical neuronal cell types, layers and how they transmit information will lead to a fuller picture of how the cortex operates and accomplishes it's remarkable achievements.
Cortical networks during sleep and wake
Sleep is thought to have homeostatic functions for our brains and has also been shown to mediate memory consolidation. Evidence for homeostatic function of sleep is that without sleep our brains malfunction: we remember poorly, our cognition because faulty, people can have psychosis and epileptic patients can have seizures. On the other hand during wake we accumulate experience and learn new information and decades of research has shown that memory is actually improved after sleep.
How does sleep both bring cells/synapses back to the status quo for homeostatic reasons and yet also reinforce new changes to become strengthened. We aim to study which cells and connections are maintained and which are pulled back to previous states after learning behaviors using a combination of high density electrophysiologic recordings, sleep and learning paradigms and optogenetics.
Major depressive disorder affects millions of people worldwide every year and yet we do not understand it's basic neurobiology. Ketamine is a rapid-acting antidepressant drug that offers a new opportunity to possibly understand the circuits underlying depression and also offers new clinical avenues forward. We will use silicon probe recordings in rodents to characterize the changes that occur before versus after ketamine infusion and will also attempt to match antidepressant-related behavioral change on a per-animal basis to neurophysiologic changes in those same animals. This may both help us understand more and give targets and markers for future clinical treatments.