Addiction may not always be a fixed personality or genetic trait, instead the result of our plastic brains learning the effect of drugs on our individual responses and the environmental setting in which the substance is used.
Activities targeting agreeableness were shown to reduce Dark Triad personality traits. However, those with Dark Triad personality disorders are less likely to want intervention to increase agreeableness.
A combination of personality traits and childhood circumstances account for why some older people experience loneliness more than others. Lonely adults over 50 were 1.24 times more likely to have rarely, or never, had comfortable friendships during childhood, and 1.34 times more likely to have had poor relationships with their mothers as children.
Students who participate in psychology classes focused on personality traits show improvements in dispositional intelligence, allowing them to better understand how the behaviors of others relate to their personalities.
People who scored high for conscientiousness lived two years longer without a decline in cognitive function than those who were less conscientious. Those who scored lower for neuroticism and higher in extraversion were more likely to regain normal cognitive function following a diagnosis of MCI, suggesting those personality traits may be associated with neuroprotection.
Family members of people with borderline personality disorder share similarities in brain structure and personality traits as those diagnosed with the personality disorder. Findings may point toward a hereditary component to personality disorders.