Personality changes following left subthalamic nucleus infarct: a case report

Abstract

The subthalamic nucleus (STN) is part of the cortico-subcortical motor and non-motor circuits and is, thus, involved in multiple associative and limbic functions. Most literatura regarding the STN describes and analyzes only its roll in motor function. We present the case of a 37-year-old woman and describe multiple cognitive, behavioral, and personality changes following surgical clipping for a ruptured left-middle cerebral artery aneurysm and a subsequent left STN infarct; no other cortical or subcortical structural lesions were found. After the incident, the patient presented with cognitive and behavioral changes, although more relevant changes were observed in her social and affective interaction patterns (i.e., personality), which were presumably influenced by negative early-life experiences. A neuropsychological assessment demonstrated normal IQ with mild attentional and executive deficiencies; personality changes were documented using a semi-structured interview. Her interaction patterns changed from a dysfunctional tendency to be emotionally distant, uncommunicative, bad-tempered, and physically aggressive to a puerile, affectionate, caring, and sociable pattern of interaction, which resulted in improved family relations. Cognitive and affective changes related to STN lesions and stimulation have, in part, been explained by the inhibitory and action-selection functions within fronto-striatal circuits, although few studies describe and analyze personality changes; most report negative changes, in contrast to the case presented here.