Non-Invasive Brain Stimulation and Substance Use

The will investigate the feasibility and effectiveness and initial efficacy of non-invasive transcranial alternating current stimulation (tACS) on distress tolerance and inhibitory control among treatment seeking substance users.

Disruptions in inhibitory control (IC) and distress tolerance (DT) are implicated in the development and maintenance of substance use disorders. Findings suggest that differential DLPFC engagement during affective and cognitive processing, and in particular, distress tolerance, in substance use disorder may be malleable, providing a promising intervention. Modulating neural oscillations with non-invasive, safe brain stimulation by targeting regions such as the DLPFC may provide an avenue to improve distress tolerance and inhibitory control in SUD. Transcranial alternating current stimulation (tACS) may be a particularly promising approach as it is a safe and non-invasive method of electric stimulation that has the potential to effectively modulate neural network and circuit dynamics, more closely aligning with a network-based conceptualization of affective and cognitive processesThis study will test the effects of tACS on distress tolerance and inhibitory control among treatment-seeking adults with substance use disorder.

Active sham transcranial alternating current stimulation (tACS) during Session 1 and Transcranial Alternating Current Stimulation at 10 Hz during Session 2

Active sham transcranial alternating current stimulation (tACS) during Session 1 and Transcranial Alternating Current Stimulation at 40 Hz during Session 2

Non-invasive, safe transcranial alternating current stimulation administered at 10 Hz to target alpha oscillatory activity

Non-invasive, safe transcranial alternating current stimulation administered at 40 Hz to target gamma oscillatory activity

The Computerized Paced Auditory Serial Addition Task (PASAT-C) is a psychological distress-inducing task. Numbers are presented sequentially on a computer screen and participants are asked to add the currently presented number to the previously presented number before the next number is presented. Participants select the answer using a computer mouse on a number pad displayed on the computer screen below the presented numbers. The speed of the number presentations is individually titrated in order to account for some individual differences in cognitive capacity, but not to secure equal performance among individuals. Incorrect or delayed responses are met with an aversive explosion sound. Distress tolerance is the latency to task termination (i.e., time until quit in minutes).

During the computerized Go/No-Go task, participants view a serial stream of pictures and are instructed to continuously press a button on the computer keyboard, but inhibit responses when stimuli are presented consecutively. Inhibitory control will be calculated as d-prime [z(hit rate) - z(false alarm rate)]. Each z-score of 0 is equal to the mean of the reference population, with a standard deviation of 1. Positive d-prime values indicate more inhibitory control, and negative values indicate less inhibitory control.

Inclusion Criteria: Current Diagnostic and Statistical Manual of Mental Disorders (DSM-V) Substance Use Disorder Current smoker Abstinent from all substances (except nicotine) for at least the past 2 weeks Exclusion Criteria: Current use of antiepileptic drugs and/or benzodiazepines Less than 6 months since an electroconvulsive therapy (ECT) session Current DSM-V Psychotic Disorder Pregnancy and/or nursing Ongoing or history of traumatic brain injury (TBI), reoccurring seizures, stroke, or brain tumors Medical or neurological illness Brain devices and/or implants