A Brazilian stroke victim recently made headlines after he was diagnosed with “pathological generosity,” a strange condition that his physicians characterize as an “excessive and persistent” urge to help others. In a case study published in the journal Neurocase, researchers theorize that the novel condition may have been induced by damage to the subcortical region, where normal behavior is regulated. The case could have a tremendous impact on the scientific community, as it represents the diametrical opposite of disorders like sociopathy and hoarding.

The 49-year-old man, referred to as “Mr. A,” reportedly began to exhibit signs of the remarkable personality change when he wouldn’t stop giving money and gifts to people he barely knew. According to his wife, he would buy candy, soda, and food for kids he met on the street. He later became unable to manage his finances, and was forced to leave his position as department manager at a large corporation.

"Stroke can cause a whole variety of neuropsychological and behavioral changes," said Dr. Larry Goldstein, neurologist and director of the Stroke Center at Duke University. Speaking to LiveScience, he noted that personality changes are not that unusual, and generally depend on the extent and location of the injury in the brain.

That said, Mr. A’s case is believed to be unprecedented, as his pathological generosity fails to align with any of the commonly observed configurations. Although the condition may seem harmless, the researchers stress that it warrants further inquiry, as it ultimately imposes severe distress and financial burden on the patient.

“This case study adds pathological generosity to the range of behavioral changes that may result from discrete unilateral lesions of the lenticular nucleus and nearby pathways,” the case study authors write. “In our particular case, post-stroke pathological generosity was not ascribable to disinhibition, apathy, mania, or depression.”

Intriguingly, the case may also illuminate the subconscious underpinnings of generosity itself. By mapping the extent of the injury, scientists may be able to pinpoint specific brain areas associated with such tendencies. Mr. A’s pathological generosity could consequently advance the knowledge of "the delicate balance between altruism and egoism, which make up one of the pillars of ordinary social motivation and decision making," the researchers write.

According to the Centers for Disease Control and Prevention (CDC), stroke is one of the leading causes of death in the U.S., with more than 800,000 annual deaths. Aside from personality changes, the condition may cause paralysis, speech difficulties, and emotional problems. To learn more about the condition, and how to lower your risks, consult the agency’s extensive online database.

Source: Rafael Ferreira-Garcia, Leonardo F. Fontenelle, Jorge Moll, Ricardo de Oliveira-Souza. An atypical impulse control disorder after a left subcortical stroke. Neurocase. 2013.