A longitudinal study of a racially and socioeconomically diverse group of girls found that those diagnosed with ADHD in childhood tend to become less conscientious, agreeable, and emotionally stable as they grow up. Girls from higher-income families tended to describe their personalities in a more negative way. The paper was published in Research on Child and Adolescent Psychopathology.
Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental condition characterized by inattention, hyperactivity, and impulsivity. Individuals with ADHD struggle with staying focused, following instructions, and managing time. Most often, it is diagnosed in childhood, usually when a child starts school. It can persist into adulthood, but symptoms tend to vary with age.
The causes of ADHD are not fully understood. However, there is an extensive list of well-studied consequences. Studies link ADHD with worse academic performance. As they grow up, individuals with ADHD often struggle to stay organized, meet deadlines, or maintain focus on tasks, leading to work-related difficulties. These individuals are also more likely to face financial problems, challenges with romantic relationships, and are at an increased risk of developing mental health issues.
Study author Laura J. Bell and her colleagues wanted to explore the relationship between inattention and hyperactivity in childhood, two defining symptoms of ADHD and personality traits in adolescence. They analyzed data from various sources and at different time points to minimize the risk of bias in their conclusions. These researchers hypothesized that children with ADHD will, on average, tend to have lower conscientiousness, be less agreeable, and less emotionally stable.
The authors analyzed data from the Berkeley Girls with ADHD Longitudinal Study, which is a longitudinal dataset that assessed ADHD in childhood and Big Five personality traits in adolescence. The Big Five personality traits are a widely accepted model that describes human personality through five broad traits: openness, conscientiousness, extraversion, agreeableness, and emotional stability (or neuroticism).
Data came from 228 girls, 140 of whom were diagnosed with ADHD, while 88 were without this diagnosis. Of the girls with ADHD, 93 had high levels of both inattention and hyperactivity. Their ADHD symptoms were assessed when they were between 6 and 12 years old, while personality assessments were conducted when the girls were between 11 and 18, i.e., when participants were old enough to rate their own personality traits.
Assessments of ADHD symptoms were collected using a parent and teacher report questionnaire (the Swanson, Nolan, and Pelham questionnaire), while ADHD diagnosis was established using the Diagnostic Interview Schedule for Children. When these girls became adolescents, they completed a popular assessment of personality—the Big Five Inventory. From this inventory, the authors calculated their personality trait scores and also developed an indicator of negative self-views in adolescence, reflecting how negatively participants described themselves.
Results showed that girls with ADHD in childhood tended to have lower scores on the personality traits of conscientiousness and agreeableness and higher scores on neuroticism. In other words, they tended to be less conscientious, less agreeable, and less emotionally stable. ADHD symptoms of inattention and hyperactivity were associated with these same personality traits in adolescence. Consequently, girls with ADHD tended to have more negative self-views as adolescents, as the negative self-view score is derived from these three personality traits.
Further analysis revealed that the strength of the link between ADHD symptoms and negative self-views depended on family income. The link was stronger in girls from high-income families, while it was weaker in girls from low-income families. The authors believe this may be due to stronger familial pressure to achieve in higher-income families, producing more pronounced negative effects of ADHD on personality development.
“Indeed, it may be that negative self-perceptions emanating from childhood ADHD are a potential mechanism by which difficult adult outcomes are perpetuated, perhaps via a “scar” model. Personality shows considerable malleability, so that if personality (or “identity”/self-concept) accounts for relations between childhood ADHD and adult dysfunction, it could potentially become an intervention target (e.g., inoculation against negative self-perceptions via psychoeducation, targeted skill building, and/or enhancement of strengths),” the study authors concluded.
The study sheds light on the links between personality and ADHD. However, it should be noted that there is substantial overlap between the concepts of inattention and conscientiousness, meaning that associations could be expected. Additionally, personality traits in adolescence are still developing and might differ somewhat from those in adulthood.
The paper, “ADHD Symptoms in Childhood and Big Five Personality Traits in Adolescence: A Five‑Year Longitudinal Study in Girls,” was authored by Laura J. Bell, Oliver P. John, and Stephen P. Hinshaw.