Deficits in visual learning produced by posterior temporal lesions in cats.

Abstract

Eight cats with lesions in the posterior temporal (PT) cortex, seven cats with lesions in the basolateral amygdala (BLA), and eight intact controls were observed on eight tests of visual discrimination learning and of spontaneous responses to salient visual stimuli. The effects of the two lesions were somewhat dissociable. The PT lesions were accompanied by a severe deficit in pattern discrimination learning but no loss in visual tracking or orientation to the silhouette of a threatening cat. The BLA lesions produced a milder and less consistent loss in pattern discrimination but serious defects in tracking and response to the cat silhouette. Both operated groups performed well on the visual cliff. The deficit from PT lesions appeared independent of damage to the geniculocortical system. The parallel of symptoms from PT lesions in cats and inferotemporal lesions in monkeys is discussed.The trans-and subcortical connections of areas 20 and 21 in the posterior temporal (PT) cortex of cats are similar to those in the inferior temporal (IT) cortex of monkeys (Heath & Jones, 1971;E. Jones, 1974). Ablations of IT cortex impair visual discrimination learning in monkeys (Chow, 1951;Pribram & Mishkin, 1955). Posterior cortical lesions impair visual learning in cats, but one can not assess the importance of destruction of areas 20 and 21 because there was extensive damage to other cortical regions in most studies (Baden,

Reorganization of the Connectivity of Cortical Field DZ in Congenitally Deaf Cat

“…The cortical areas 19/20a-20b are considered as purely visual, they contain a full representation of the contralateral visual field having neurons with large receptive fields [84], [85]. Indeed, behavioral studies in cats have implicated the areas 20/21 in visual learning of pattern discrimination [86]–[88]. It is consequently probable that the direct projections we observed from areas 20/21 to DZ contribute to the visual function supported the dorsal auditory zone.…”

Subtotal lesions of the visual cortex impair discrimination of hidden figures by cats.

“…The performance of the three groups on the tracking task is displayed in Figure 4, along with that of the control group reported by Campbell (1978) and tested intercurrently with the cats of the present experiment. Both of the control subjects that were tested obtained tracking scores near the maximum, and their performances were indistinguishable from that of the larger group of normal cats reported by Campbell.…”

“…The procedure in the landmark discrimination (Task 14) was the same as that used previously by Campbell (1978). All testing was conducted in the apparatus with white goal compartments, and all 14 subjects were tested.…”

Functional specialization in the lower and upper visual fields in humans: Its ecological origins and neurophysiological implications

“…In fact, Diamond and Hall (1969) argued that the expansion of the temporal visual areas represents one of the most salient features of primate evolution. Although it has since been shown that at least some rudimentary parallels exist between cats and monkeys (Campbell 1978), other researchers continue to doubt whether a clearcut homologue of the primate inferotemporal areas Is found in this species (Tusa & Palmer 1980). The primate occipitotemporal pathways, however, are distinguished not only by their anatomical expansion but also by their unique functional specializations.…”