Fast Rhythmic Bursting Cells: The Horizontal Fiber System in the Cat’s Primary Visual Cortex

One of the cellular mechanisms underlying the generation of gamma oscillations is a type of cortical pyramidal neuron named fast rhythmic bursting (FRB) cells. After 58 cells from 21 cats' primary visual cortices were filled with Neurobiotin, the brains were cut, and the cells were photographed. From all cells, 1 non-pyramidal and 4 pyramidal cell (3 regular spiking (RS) cells & 1 FRB cell) were confocaled, reconstructed with Neurolucida, and analyzed with NeuroExplorer. All 5 cells showed a linear correlation (>0.94) between length and number of intersections. Their polar histograms indicated that the FRB cell has triple dendritic length, twice the number of dendritic tree orders and mean length compared to the 4 other cells. We propose that FRB cells are key elements of the horizontal fiber system that links cell populations with similar feature selections throughout the primary visual cortex.