Selective sparing after lesions of visual cortex in newborn kittens.
Previous findings are discordant regarding the effects of perinatal lesions of Cortical Areas 17 and 18 on visual discrimination learning in cats. Three potential determinants of such sparing were investigated: age at lesion (4 or 181 days), age at testing (3 or 9 months), and stimulus complexity. Age at testing was not significant, but performance varied with stimulus complexity and cortical damage, and there was an interaction between stimulus complexity and age at lesion. Both operated groups were transiently impaired in discriminating objects and subsequently learned to discriminate simple 2-dimensional patterns as well as done by controls, but the lesion groups were permanently impaired in discriminating similar patterns circumscribed by irrelevant lines. The age-at-lesion groups differed, however, in discriminating patterns masked by superimposed lines. The group lesioned at 181 days was severely impaired at both acquisition and subsequent intercurrent performance; the group lesioned at 4 days was impaired only at intercurrent performance. This study suggests that sparing after early postnatal damage of Areas 17 and 18 occurs only under limited circumstances.
Cornwell
P
P
Department of Psychology, Pennsylvania State University, University Park 16802.
Herbein
S
S
Corso
C
C
Eskew
R
R
Warren
J M
JM
Payne
B
B
D000818:Animals; D001143:Arousal / Q000502:physiology; D001288:Attention / Q000502:physiology*; D001931:Brain Mapping; D002415:Cats; D004193:Discrimination Learning / Q000502:physiology*; D005556:Form Perception / Q000502:physiology*; D005829:Geniculate Bodies / Q000502:physiology; D009410:Nerve Degeneration / Q000502:physiology; D009474:Neurons / Q000502:physiology; D009949:Orientation / Q000502:physiology; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010470:Perceptual Masking / Q000502:physiology; D014793:Visual Cortex / Q000502:physiology*; D014795:Visual Pathways / Q000502:physiology