Neurons in area 18 of cat visual cortex selectively sensitive to changing size: Nonlinear interactions between responses to two edges

doi:10.1016/0042-6989(79)90247-5

Vision Research

Volume 19, Issue 6, 1979, Pages 699-711

https://doi.org/10.1016/0042-6989(79)90247-5 Get rights and content

Abstract

Searching for a neural correlate of the psychophysical channels for increasing and decreasing size, we quantitatively studied 56 units in area 18 of cat visual cortex. We compared responses evoked by expanding and contracting slits with the sum of spike counts evoked by individual movements of the two stimulating edges. All 56 units responded to changing-size, but 19 of these could be described as simply responding to changing light level. Thirty units fired preferentially to expansion (or contraction) independently of whether the stimulus slit was bright or dark. At first sight these 30 units looked like changing-size neurons, but 20:30 reversed their bias when stimulus location was changed. Only one cell unequivocally distinguished between expansion and contraction. On the other hand,interactions between responses to the two edges had the effect of emphasizing changing-size information in many units, not unequivocally, but with a probability greater than pure chance. Thus, although units specifically sensitive to changing-size are rare in area 18, the population behaviour of a common type of area 18 neuron is capable of signalling changing-size information.

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: This work was presented to ARVO at the 1978 Sarasota meeting (Invest. Ophthal., ARVO Abstracts, 1978).

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Neurons in area 18 of cat visual cortex selectively sensitive to changing size: Nonlinear interactions between responses to two edges

Abstract

Vision Res.

Vision Res.

Vision Res.

Changing-size filters for different object sizes

Vision Res.

Interaction effects of visual contours on the discharge frequency of simple striate neurons

J. Physiol., Lond.

Nonlinear Systems Analysis

Multiple meaning in single visual units

Brain Behav. Evol.

Receptive-field organization of monkey superior collicus

J. Neurophysiol.

Recovery of function in cat visual cortex following prolonged deprivation

Expl Brain Res.

Neural mechanisms underlying stereoscopic depth perception in cat visual cortex

Neurons in cat parastriate cortex sensitive to the direction of motion in three-dimensional space

J. Physiol., Lond.

Autocorrelation and automatic integration

Electroenceph. clin. Neurophysiol.