What We Do?

In fields such as clinical psychology and psychiatry, clinical diagnoses are based on observable behaviors, signs, and symptoms, and/or phenomenological reports of those signs and symptoms. These clinical diagnoses are advantageous and have utility for purposes including communication between affected individuals and professionals or between institutions and professionals. These clinical diagnoses are also advantageous for making group-level descriptions and predictions but evidence has been accumulating to show that they are less useful for making individual-level predictions. In other words, clinical diagnoses are less useful for estimating what any given individual with a certain set of signs and symptoms will experience in terms of outcomes on the short- or on the long-term.

One hypothesis is that clinical diagnoses are less useful for individual-level prediction because they describe heterogeneous – multifaceted – phenotypes that can be caused by a variety of factors and that can lead to a variety of outcomes. Intermediate phenotypes are characteristics, traits, that are close to the causes of a condition than the clinical phenotype but are also more homogeneous than the clinical phenotype. As a result, intermediate phenotypes are hypothesized better explanatory and prognostic power, meaning they are more informative – and more precisely informative – about the etiology and the likely outcomes associated with a clinical presentation.

We had been primarily (but not solely) focusing on attention-deficit/hyperactivity disorder (ADHD) as the clinical diagnosis of interest, on differences in reinforcement sensitivity (punishment and reward sensitivity) as the intermediate phenotype of interest, and on differences in behavioral problems including aggression, bullying/victimization, delinquency, risk-taking, and substance use as outcomes of interest. We have been aiming to determine the extent to which rather than focusing only on ADHD clinical diagnoses, also focusing on differences in various measures of reinforcement sensitivity brings us closer to understanding what characteristics are implicated in ADHD risk and to identifying individuals with ADHD who are more/ less likely to experience negative outcomes.

We use clinical, neuropsychological, genetic, electrophysiological, and neuroimaging methods and work with adolescents, their families, and their teachers. We have several large studies ongoing, including a longitudinal research, the Budapest Longitudinal Study of ADHD and Externalizing Disorders (BLADS).