Visual responses of neurons in the dorsolateral amygdala of the alert monkey

doi:10.1016/0014-4886(79)90175-4

Experimental Neurology

Volume 63, Issue 3, March 1979, Pages 610-626

https://doi.org/10.1016/0014-4886(79)90175-4 Get rights and content

Abstract

There is evidence that the inferotemporal visual cortex in the monkey projects to the amygdala, and evidence that damage to this region impairs the learning of associations between visual stimuli and reward or punishment. In recordings made in the amygdala to determine whether or not visual responses were found, and if so how they were affected by the significance of the visual stimuli, neurons were found in the dorsolateral part of the amygdala with visual responses which in most cases were sustained while the animal looked at effective visual stimuli. The latency of the responses was 100 to 140 ms or more. The majority (85%) of these neurons responded more strongly to some stimuli than to others, but physical factors which accounted for the responses of the neurons, such as shape, size, orientation, color, or texture, could not usually be identified. Although 22 (19.5%) of these neurons responded primarily to food objects, the responses were not uniquely food-related. Furthermore, although some neurons responded in a visual discrimination test to a visual stimulus which indicated reward, and not to a visual stimulus which indicated saline, only minor modifications of the magnitude of the neuronal responses to the stimuli were obtained when the reward-related significance of the stimuli was reversed. The visual responses of these amygdaloid neurons were thus intermediate in some respects between those of neurons in the inferotemporal cortex, which are not affected by the significance of visual stimuli, and those of neurons in a region to which the amygdala projects, the lateral hypothalamus and substantia innominata, where neurons respond to visual stimuli associated with food reward.

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²: The present addressof Dr.Sanghera is: Department of Physiology, University of Texas, Health Science Center, Dallas, Texas 73235, U.S.A.

¹: This work was supported by the Medical Research Council. The excellent contributions of Drs. W. P. C. Mills and P. M. Farley to the programs for the on-line neurophysiological data analysis are gratefully acknowledged.

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Visual responses of neurons in the dorsolateral amygdala of the alert monkey

Abstract

Electroencephalogr. Clin. Neurophysiol.

Exp. Neurol.

Brain Res.

Brain Res.

Exp. Neurol.

Exp. Neurol.

Exp. Neurol.

Trends Neurosci.

Brain Res.

Brain Res.

Klüver-Bucy syndrome in monkeys with neocortical ablations of temporal lobe

Brain

Inferotemporal cortex and vision

Reactivity of limbic neurons of the monkey to appetitive and aversive signals

Electroencephalogr. Clin. Neurophysiol.