Selective sensitivity of the cat striate neurons to cruciform and angular figures of various orientations

A model of a neuronal network for detection of single bands and cross-like figures

“…The ratio in this case is 2.75. Figure 3, B shows polar plots for the tuning orientation of an experimentally measured cross detector for stimuli consisting of a single band (1) and CLF in which the angle between the bands is 90 ~ (2). Unlike the model neuron, the "live" neuron produces similar responses to close CLF orientations, making its TO wider.…”

“…The selectivity of this neuron is 2.72. Figure 4, B shows polar plots of the TO of an experimentally recorded neuron to a single band (1) and a CLF with an angle of 90 ~ between the bands. The PO of this neuron is 45~ its TO is sharper than that of the model neuron.…”

“…Neurophysiological experiments have demonstrated that nearly four out of every five neurons with sensitivity for CLF have monomodal tuning orientations for single bands [1,6]. A neuronal network modeling this type of detector (Fig.…”

“…The model was used to study the properties of a "cross detector" constructed on the basis of convergence of excitatory connections with different weightings from elements with different orientational tuning. It is shown that a cross detector with monomodal orientational tuning needs an amplifier mechanism (a reverberator).Detectors of cross-like figures (CLF) and cells identifying "local disruptions in orientational continuity" have recently been observed in the primary projection area of the visual cortex in cats and monkeys by two groups of investigators [1,2,[5][6][7]. Between one third and one half of the neurons were found to increase their responses several-fold as compared with their responses to single bands of the preferred orientation when their receptive fields (RF) were stimulated with flashing cross-like figures with configurations and orientations specific for a given cell [1,2,5,6] or with two orthogonal grids in the center and periphery of the RF [7].…”

“…Between one third and one half of the neurons were found to increase their responses several-fold as compared with their responses to single bands of the preferred orientation when their receptive fields (RF) were stimulated with flashing cross-like figures with configurations and orientations specific for a given cell [1,2,5,6] or with two orthogonal grids in the center and periphery of the RF [7].…”