Abstract

A Case of Right Frontal Lobe Dysfunction with Risk Behaviors, Despite Normal General and Risk Cognition: Misunderstood as Cheerful, Active, and Careless Character?

Author(s): Junko Takada, Kenichi Meguro, Keiichi Kumai, Takako Kamata, Shigeo Kinomura, Satoshi Yamaguchi

Some older community residents can exhibit baffling behaviors in daily life, despite their memory and general cognitive functions being normal. Thus, they may be superficially suspected to have a psychiatric disease. We experienced a case in which risk behaviors related to fire, consumer damage, fall, etc. and hyperactivity were observed in daily life; despite general cognitive function being within a normal range. Her abnormal behaviors were summarized by behavioral neurology, as follows: 1) hyperactivity caused by right hemisphere damage, 2) decreased right frontal lobe function caused by right frontal lobe damage, and 3) confabulation caused by disinhibition of the left frontal lobe. Thus, we performed neuroimaging examinations, and found right basal ganglia infarction (MRI) and decreased blood flow to the right frontal lobe (single photon emission computed tomography [SPECT], remote effect). After a service representatives meeting, where the physician in charge provided an explanation, the patient, who did not like drug administration by nature, and had thus refused recommendations from her home doctor, began to be conscious about her disease and agreed to undergo drug treatment. It is not easy to explain the relationship between cerebral infarction in a strategically important region and daily life (behavior). This is the specialty of dementia medicine. When a disease is found to exhibit cerebral injury, the patient will be able to correctly understand the disease, and appropriate care will be promoted under the health management and collaboration between medical and nursing care.