Functional organization of mouse barrel cortex.

• Main Author: Zheng, Sophia Yuan Yun.
• Other Authors: School of Biological Sciences
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Science::Biological sciences::Human anatomy and physiology::Neurobiology
• Online Access: http://hdl.handle.net/10356/16322
• Institution: Nanyang Technological University

Primary somatosensory cortex is a six-layered structure useful for studying the spatial organization of synaptic processing within a column of cortical circuitry. For this purpose, I used voltage-sensitive dye imaging (VSDI) to visualize synaptic transmission within in vitro slice preparations of the mouse barrel cortex. The goals of my work were to examine the patterns of the functional input and output of the barrel cortex, as well as the functional independence of neighboring barrels. Stimulation at layer IV and V showed a columnar spread of optical signals to layer II/III before propagating across to the supragranular layers. Signals also propagated from the stimulated barrel to the adjacent supragranular layers before propagating to the neighboring barrel. No direct inputs were observed from adjacent barrels. At the septal between adjacent barrels, optical signals were lower than in the barrel column. Also, when layer II/III region was stimulated, weak optical signals were observed in layer IV and V of the same barrel. These results suggest that layer IV barrels indeed do not receive direct inputs from neighboring barrels and that they function as independent parallel processors.