Biological Sciences Training Program (BSTP): "Functional Ultrasound Imaging During Behavior: Tales from Rats and Marmosets"

Dr. Ahmed El Hady, Ph.D., Associate Research Scholar at the Neuroscience Institute of Princeton University, will be giving the BSTP seminar. His talk is entitled, "Functional ultrasound imaging during behavior: tales from rats and marmosets". The seminar is hosted by the Department of Molecular Psychiatry.

Abstract:

In complex cognitive behaviors, it is rarely clear which brain areas may be involved, let alone at which temporal or spatial resolution In fact, such behaviors exhibit both complex dynamical computation within individual populations, as well as high between-area processing. Therefore it is critical that methodologies be developed that can assess large areas of the brain during these behaviors to simultaneously uncover large-scale interactions and guide further, targeted experimental recordings. As the neuroscience community is gearing towards more complex and naturalistic behaviors, there is a need to complement our technical toolkit with a method that can capture brain dynamics unfolding over extended temporal and spatial scales. Functional ultrasound imaging (fUSi) is an emerging technology that allows us to image the transient changes in cerebral blood volume (CBV), which are proportional to changes in neural activity. fUSi has excellent spatial coverage (16mm X 20mm), and good spatial resolution (~100 X 100 μm in coronal image sections of 400 μm thickness); its temporal resolution is 100 - 500 milliseconds. Therefore, it allows imaging cortical and sub-cortical areas simultaneously.

I will present two applications of functional ultrasound imaging during behavior. First concerning marmoset vocal behavior and the second concerning rodents’ decision making dynamics. In marmosets, we were able to image for the first time a set of medial brain areas (what we call social-vocal network; SVN) at the intersection of social behavior network, vocal production and perception areas that are crucial for social vocal communication. In rodents, we were able to image a number of cortical and sub-cortical brains areas that are modulated by choice during evidence accumulation. Our results highlight the crucial importance of fUSi to rapidly screen and characterize brain areas that are involved in complex behaviors. I will also discuss the future of functional ultrasound techniques in realizing whole brain imaging and combining it with other neurophysiological techniques for circuit-level perturbations.