Responses of visual, somatosensory, and auditory neurones in the golden hamster's superior colliculus

Abstract

6. Directional selectivity was also tested for ninety-two cells following acute, unilateral, lesions of the visual cortex. For the eighty cells recorded, homolateral to the ablated cortex, 275 % were judged as directionally selective using the statistical criterion, while 12-5 % were selective with the 'null' criterion. Of the twelve cells isolated in the colliculus, contralateral L. M. CHALUPA AND R. W. RHOADES to the lesions, seven were judged as directionally selective with the statistical, and three with the 'null' criterion.7. The effects of visual cortical lesions upon directional selectivity appeared to be confined to cells in the superficial layers of the colliculus. It was suggested that directional selectivity of many cells in the superficial layers of the tectum of the hamster is organized cortically.8. A clear spatial correspondence was observed for the receptive-fields of visual, somatosensory, and auditory neurones.9. As has been suggested for other species, the hamster's superior colliculus appears to play an important role in orienting the animal toward visual, somatosensory, and auditory stimuli.

Sensory regulation of dopaminergic cell activity: Phenomenology, circuitry and function

“…Miller et al, 1981), as are neurons in the SC (Drager and Hubel, 1975, Chalupa and Rhoades, 1977, Stein and Meredith, 1993, Wallace et al, 1996. Despite this, we have not been able to produce (phasic) activations in DA neurons using whisker pad stimulation following GABA A antagonist injections into the SC.…”

“…However, the SC is a multi-sensory structure containing neurons which respond to visual, auditory and somatosensory stimulation (Drager and Hubel, 1975, Chalupa and Rhoades, 1977, Stein and Meredith, 1993, Wallace et al, 1996. As a consequence, it was natural for us to examine whether the SC is the primary source of sensory input to DA neurons for a modality other than vision.…”

Inhibitory Plasticity Facilitates Recovery of Stimulus Velocity Tuning in the Superior Colliculus after Chronic NMDA Receptor Blockade

“…Neurons in the BP category responded best to an intermediate velocity, with responses falling below 50% of their maximum at the lowest and at the highest velocities tested. Low-pass neurons generally did not respond better to stationary than moving stimuli, but the response of HP neurons would be expected to decline with stimuli faster than 45°/s based on previous work (Chalupa and Rhoades, 1977;Razak et al, 2003). Nonselective neurons by definition responded at Ͼ50% of maximum at all velocities tested.…”

“…For most of the experiments in this study, the direction of stimulus sweep was temporal-to-nasal with respect to the animal. The choice of stimulus velocities used was guided by previous results showing that the majority of hamster SC neurons are selective for slowly moving (Յ10°/s) stimuli (Tiao and Blakemore, 1976;Chalupa and Rhoades, 1977;Stein and Dixon, 1979;Pallas and Finlay, 1989;Razak et al, 2003). Each stimulus set was typically repeated at least five times, although fewer trials were collected in some cases in which a large number of tests were being done on the neuron.…”

Altered somatosensory receptive fields in hamster colliculus after infraorbital nerve section and xylocaine injection.

“…The spontaneous activity, response modality and responsitivity to spinal trigeminal shocks were noted for each cell. The receptive field of each visual cell was plotted on a tangent screen (Chalupa & Rhoades, 1977) and response properties were assessed either manually (in most cases) or with a computer-controlled movement stimulator (Chalupa & Rhoades, 1977;Mooney, Fish & Rhoades, 1984).…”