Effects of caudate nuclei or frontal cortical ablations in kittens: Maze learning

Abstract

Cats which had received bilateral lesions of the caudate nuclei and the frontal cortices during the first month of life were tested as juveniles on T-maze position habit and spatial reversal tasks. Intact and sham-operated littermates served as controls. All animals of all groups were capable of learning the spatial discrimination and to successfully reverse that habit. While maintaining many of the perseverative characteristics of adult-operated acaudates, the kitten-operated acaudates showed the fewest number of trials to acquire the position habit and to complete 30 reversals. There was a direct relationship between the size of the lesion and the number of perseverative errors made by the acaudate animals. The afrontal cats showed more reversal errors and were unmotivated and distractable. The data suggest for the tasks used here that although there may be similar qualitative deficits the overall effects on performance are not as great when the lesion is inflicted in the neonate compared to the adult. The data imply that many factors contribute to this recovery, e.g., early experience.