Effects of dorsolateral frontal cortex lesions and discrimination-alternation training on regional acetylcholinesterase activity in monkey

Summary Twenty adult female rhesus monkeys (Macaca mulatta) were divided into 4 treatment groups of 5 subjects each; nonlesioned-nontrained (NLNT), nonlesioned-trained (NLT), lesioned-nontrained (LNT), and lesioned-trained (LT). All lesions were bilateral ablations of dorsolateral frontal cortex. The training consisted of color discrimination and delayed alternation. AChE activity was determined for 19 brain regions in each subject. Significant changes in AChE activity due to the lesion were found in orbital cortex, caudate nucleus and pons while training procedures produced significant changes only in the orbital cortex. The 3 brain areas in which significant AChE changes were found bear a close anatomical and functional relationship to the lesioned prefrontal cortex.