Variable Discharge Pattern and Contrast Invariant Orientation Tuning of a Simple Cell: A Modeling Study
نویسندگان
چکیده
The orientation tuning width of the spike response of neuron in V1 does not change with the contrast of input signals. It is also known that cortical neurons exhibit tremendous irregularity in their discharge pattern, which is conserved over large regions of cerebral cortex. To produce this irregularity in responses the neurons must receive balanced excitation and inhibition. By a modeling study we show that, if this balance is maintained for all levels of contrast, it results in variable discharge patterns of cortical neurons at all contrast and also in contrast invariant orientation tuning. Further, this study supports the role of inhibition in shaping the responses of cortical neurons. Keywords—Database Orientation tuning, simple cells, complex cells, visual cortex
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