Prefrontal cognitive dysfunction following brainstem lesion

Prefrontal cortex (PFC) dysfunction can lead to impairment in planning and behavioral inhibition, as well as personality changes. As ascending monoaminergic brainstem systems modulate PFC functioning, it is possible that lesions in the brainstem lead to symptoms similar to prefrontal dysfunction. A 29-year-old man developed several cognitive and behavioral symptoms after neurosurgery for resection of a pilocytic astrocytoma in the pontine-mesencephalic area. A careful analysis of symptoms indicated PFC dysfunction that could be attributed to lesions in the ascending monoaminergic brainstem systems. Interestingly, the cognitive symptoms improved after treatment with methylphenidate, which is a drug that modules catecholaminergic neurotransmission, thereby supporting this hypothesis. This is a unique case of PFC dysfunction that may be related to post-operative lesion of the catecholaminergic nuclei in the brainstem.