The use of transcranial direct current stimulation (tDCS) to reduce impulsivity and aggression in adults with mild intellectual developmental disabilities: the tDCS-RIADD randomised controlled trial protocol

BACKGROUND: Challenging behaviours, in particular aggressive behaviours, are prevalent among people with intellectual developmental disabilities. Predictors of challenging behaviours are numerous, including past history of aggression, poor coping skills and impulsivity. Factors like motor or rapid-response impulsivity (RRI) have neurobiological underpinnings that may be amenable to change via neuromodulation using non-invasive brain stimulation techniques like transcranial direct current stimulation (tDCS). METHODS: This study aims to determine the efficacy of anodal tDCS in reducing RRI and incidents of aggression in people with intellectual developmental disabilities (IDD) in residential or hospital settings. Using a single blind, randomised, sham-controlled trial design, adults with IDD, with a history of impulsivity leading to aggression, will be randomised to receive either repetitive anodal or sham tDCS applied to the left dorsolateral prefrontal cortex. Outcome measures assessing impulsivity and aggression will be collected for up to 1 month following the last tDCS session. DISCUSSION: The results of this study may pave the way for developing targeted interventions for impulsivity and aggressive behaviours in people with IDD.