Instrumental reversal learning and subsequent fixed ratio performance on simple and go/no-go schedules in neodecorticate rabbits

Abstract

Neodecorticated rabbits (94%-97% of neocortex removed) were able to acquire and repeatedly reverse an instrumental two-treadle differentiation based on food reward. Completion of 15 reversals of the two-treadle differentiation by the neodecorticates was followed by successful training on fixed ratio (FR) schedules as high as FR 60. The neodecorticates’ rate of treadle pressing on FR was lower than normals’, but efficiency was high and food-tray-related behaviors did not intrude on the treadle-press response. The improvements in FR performance in these neodecorticates in comparison with those in previous studies was interpreted as a result of enhanced manipulandum identification produced by the prior reversal training. The neodecorticates were impaired, however, in their ability to form reversal learning sets and in the establishment of go/no-go performance on a FR baseline. Possible interpretations of the data in terms of Pavlovian and instrumental learning and the differential representation of these two processes in the brain were considered. © 1979, Psychonomic Society, Inc.. All rights reserved.