A Trial of Two-Week Brain Stimulation for Teenagers With ADHD

Working memory (WM) is the foundational cognitive control process of holding information 'in mind' to execute goal-directed behaviors. WM deficits are an established component of all primary childhood psychiatric disorders, most notably ADHD. Despite being one of the strongest predictors of poor clinical and functional outcomes in pediatric mental health, there remains a dearth of available treatments for WM deficits. Non-invasive brain stimulation holds tremendous promise in transforming psychiatry, as it takes a "brain-first" approach to treatment. The dorsolateral prefrontal cortex (DLPFC) is the known structural foundation of WM, and the interaction between slow and fast brain waves (i.e., "theta-gamma coupling \[TGC\]") is a neural, functional foundation of WM. Thus, the DLPFC and TGC are potential brain-based targets for the modulation of WM with brain stimulation. Intermittent theta burst stimulation (iTBS) is a novel paradigm that applies a three-minute dose of stimulation to the DLPFC at an intensity that directly mimics TGC dynamics. The objective of this study is to utilize the experimental therapeutics approach to investigate whether iTBS can lead to a lasting modulation of WM-related neural oscillations. In a crossover, double-blind design, a sample of adolescents (12-18 years old) with ADHD and WM deficits will complete a two-week course of active iTBS and a two-week course of sham iTBS to their left DLPFC. The central hypothesis is that iTBS at the left DLPFC will modulate TGC and subsequently improve attentional/WM abilities in adolescent WM deficits. Aim 1 will examine the effect of iTBS on TGC and attention/WM (i.e., target engagement). Aim 2 will examine the relationship between change in TGC and attention/WM performance and symptoms (i.e., target validation). The exploratory aim will identify the neocortical circuitry underlying oscillatory modulation. A secondary and clinical objective is to examine the safety/tolerability and preliminary efficacy of iTBS on ADHD-related symptoms. Participants that complete the primary study procedures will be offered the opportunity to receive more iTBS sessions via participation in an optional open label arm. Participants will have the option of selecting an accelerated iTBS approach or the traditional, daily iTBS approach. Both approaches will administer 1800 pulses of iTBS to the left DLPFC per session. The accelerated protocol will administer iTBS twice per day for 10 days and the traditional protocol will administer iTBS once per day for 20 days.