Understanding Emotional Dysfunction, Heterogeneity, and Treatment Response among Youth with Attention-Deficit/Hyperactivity Disorder (ADHD): A Biological Perspective

Attention-deficit/hyperactivity disorder (ADHD) is the most prevalent psychiatric disorder diagnosed in childhood (i.e., 11% of youth), with a public health costs estimated annually at $42.5 billion. The most common evidence-based treatment for ADHD includes stimulant medications (e.g., methylphenidate [MPH]). Although effective in reducing primary symptoms of ADHD, limited studies have examined how MPH impacts secondary characteristics (e.g., emotional dysfunction). Well-validated and reliable indexes associated with emotional functioning include biological measures of the autonomic nervous system (ANS). For instance, respiratory sinus arrhythmia (RSA) has been associated with parasympathetic activation and functions requiring effortful regulation such as emotion regulation, while electrodermal activity (EDA) has been associated with sympathetic activation and emotional reactivity.

Leveraging data collected during a larger medication study, the current proposal examined the impact of MPH on autonomic functioning within an emotional context among youth with attention-deficit/hyperactivity disorder (ADHD; Aim 1a), considered for MPH dosage (Aim 1b), and heterogenous response to MPH using existing nosology (Aim 2). Further, the current study assessed autonomic functioning holistically (via k-Means algorithm) to predict behavioral disruptions (Aim 3).

Results indicated that MPH improved emotional functioning (indexed via RSA and EDA) among youth with ADHD to comparable levels as typically developing youth at the trait and state level. Further, youth with ADHD exhibited heterogenous autonomic functioning. The results of the current study should be examined further for its utility to advance individualized treatment protocols to reduce the public health burden of ADHD.

Major Professor: Dr. Erica Musser