tDCS and cognitive training as a neurodevelopmental intervention in FASD

PROJECT SUMMARY / ABSTRACT Fetal alcohol spectrum disorders (FASDs) comprise a range of effects from prenatal alcohol exposure (PAE) including neurological abnormalities, cognitive and behavioral impairments, growth retardation, and craniofacial anomalies. Very few treatments have been investigated despite the tremendous public health burden posed by FASD. Cognition is a natural target for intervention because deficits contribute to problems with adaptive functioning, social skills, and independent living. A decade of research suggests that cognitive training has beneficial effects on functional brain networks - mediating cognition in a variety of neurodevelopmental and mental health conditions. We believe it can improve cognitive performance in individuals with FASD. The primary objective of our existing line of neuromodulation research and the proposed RCT is to leverage the ability of tDCS to enhance cortical excitability and neural plasticity in order to maximize the cognitive training benefits in children and adolescents with FASD. Recently we carried out a pilot randomized controlled trial of tDCS-augmented cognitive training to demonstrate the safety and feasibility of this approach in children with FASD (Boroda, Krueger, et al., 2020). We showed that the intervention was safe and well-tolerated in this population. Further, despite applying a relatively low-dose of tDCS and cognitive training, we found that the group receiving active-tDCS demonstrated greater improvements on an attention task than a group receiving sham-tDCS. These promising pilot results merit replication in a larger clinical trial. We propose a fully-powered randomized controlled trial of 60 (at completion) children and adolescents with FASD who will receive cognitive training in combination with tDCS. We hypothesize that, in conjunction with cognitive training, five initial sessions of active tDCS will produce a significantly greater improvement in sustained attention (CPT) than sham tDCS. We also hypothesize that, in conjunction with cognitive training, a total of ten sessions of active tDCS will produce a significantly greater improvement in sustained attention (CPT) than five sessions of active tDCS. We also aim to establish the long-term durability of neurocognitive improvements and associated behavioral changes resulting from tDCS and cognitive training. Finally, we plan to use pre-intervention and post-intervention resting-state fMRI data to show functional network changes related to the intervention and to quantify the relationship between dose and functional network changes. Results of the trial will directly inform future clinical implementation of cognitive training and tDCS as a potential neurodevelopmental intervention.