March 13, 2017 13:30 - 14:30
The neuronal organization of the mammalian neocortex has been the focus of intense study for more than a century. One long-standing hypothesis is that neocortical neurons organize into massively repeated structures in diverse functional areas, representing common motifs of information processing. However, the existence of such repeated structures remains unclear. Here we demonstrate that major cell types in neocortical layer 5 form a lattice structure in many brain areas. Large-scale three-dimensional imaging revealed that distinct types of excitatory and inhibitory neurons formed cell-type-specific radial clusters termed microcolumns. Thousands of microcolumns, in turn, were patterned into a hexagonal mosaic tessellating diverse regions of neocortex. Microcolumn neurons demonstrated synchronized in vivo activity and similar visual responses. In early postnatal development, microcolumns were coupled by cell-type-specific gap junctions and later served as hubs for convergent synaptic inputs. Thus, layer 5 neurons organize into a brain-wide modular system providing a template for cortical processing.
- BSI Private Event
- Hiroyuki Kamiguchi [Hiroyuki Kamiguchi, Neuronal Growth Mechanisms ]