PhD Scientific Days 2024

Poster Session D - Neurosciences 1.

Are cortical columns ubiquitous? High-resolution identification of functional domains in cat visual cortex using 3D functional ultrasound imaging

Text of the abstract

In the cortex of carnivore and primate model species, specific sensory features are encoded into functional maps. It remains unclear how the layout and interrelations of functional maps observed from surface layer activity generalize to deeper cortical layers. Cortical functional maps can be identified using electrophysiology with high temporal but spatially sparse sampling, impeding a holistic understanding of functional organization. Optical imaging can provide spatially extended sampling of cortical activity, but optical access is limited to about 1 mm depth, i.e. cortical layer 2/3 in large brains. FMRI provides information without tissue disruption albeit at limited resolution in space and time. To bridge the gap between established options for sampling brain activity, we applied functional ultrasound imaging to resolve the 3D structure of cortical functional maps. We performed longitudinal recordings from a large part of the cat visual cortex. We analyzed stability and spatial clustering of 3D architecture of functional domains across the visual cortex and identified rules of interrelation between distinct functional maps. Comprehensive identification of the functional architecture in the visual cortex at balanced coverage and resolution provides a new perspective on the functional architecture in the visual cortex of large-brained species, extending the classical columnar view.