Retention of Spatial Delayed Alternation in Rats with Lesions in the Frontal Lobes

Abstract

Intact rats acquired spatial delayed alternation in a T-maze. Lesions in the anteromedial cortex or the caudate nucleus impaired retention of alternation; removal of the frontal poles did not. Delayed alternation is mediated by the cortical projection field of the mediodorsal thalamic nucleus and the caudate nucleus in a rodent species as in primates and carnivores, possibly indicating inheritance of this structure-function relation from a common ancestor. No functional resemblance between the frontal poles of rats and the prefrontal cortex of monkeys, cats, and dogs is found.