Modulating Reward Processing with tDCS to Reduce Alcohol Consumption in Heavy Drinkers

Wed, 16 Sep 2026 01:00:00 +0100

Project Overview

This project examines whether transcranial direct current stimulation (tDCS) can modulate neural mechanisms of reward processing in heavy drinkers. It will test whether stimulation can attenuate the heightened motivational value attributed to alcohol-related cues while enhancing neural responsiveness to alternative, natural rewards. The study will also investigate whether these neurophysiological changes are associated with changes in alcohol consumption behaviour.

Background

Alcohol use disorder (AUD) is characterised by dysregulated reward processing, in which alcohol-related cues acquire excessive motivational salience relative to non-drug rewards. This imbalance is reflected in neurophysiological measures, including enhanced neural reactivity to alcohol cues and reduced responses to natural rewards. Such alterations are closely linked to craving, compulsive alcohol use, and relapse. Importantly, reward-related neural biases may be modifiable. Neuroimaging and electrophysiological studies have reported more normative patterns of reward-related brain activity following sustained abstinence. More recently, non-invasive brain stimulation approaches, including tDCS, have shown potential to influence reward-related processes through modulation of prefrontal–striatal activity. By targeting the neurocognitive mechanisms underlying alcohol-related reward dysregulation, tDCS may provide a promising translational approach for reducing problematic drinking. However, the extent to which tDCS modifies electrophysiological markers of alcohol and natural-reward processing, and whether such changes translate into behavioural outcomes, remains to be established.

Research Aims

Determine whether tDCS can reduce biased neural responses to alcohol-related cues relative to natural reward stimuli
Examine pre- to post-intervention changes in electrophysiological markers of reward processing, specifically P3 and late positive potential (LPP) amplitudes
Assess whether tDCS-related changes in neural reward processing are associated with changes in executive functioning
Establish whether these effects extend to behavioural measures of alcohol consumption in both laboratory and real-world contexts

Methods

Experimental Paradigm

Participants will complete a passive image-viewing task during EEG recording, together with tasks assessing executive functioning. The experimental stimuli will include alcohol-related images, non-alcoholic beverages, neutral objects, and natural rewards. The tDCS intervention will be combined with cognitive training and image viewing. Neural responses, executive-function performance, and behavioural measures of alcohol consumption will be assessed before and after the intervention. The primary electrophysiological outcomes will be P3 and LPP responses to alcohol-related and alternative reward stimuli.

tDCS Protocol

Target region: left dorsolateral prefrontal cortex (DLPFC)
Stimulation type: excitatory tDCS at 1.6 mA
Design: active, sham-controlled experimental design

Behavioural and Clinical Measures

Alcohol consumption motivation will be assessed using an Alcohol Taste Task. Self-report measures will assess craving, self-control, impulsivity, executive functioning, reward sensitivity, motivation to reduce drinking, psychological distress, and alcohol reinforcement.

Sample and Study Design

The study will recruit non-treatment-seeking heavy drinkers who are motivated to reduce or stop drinking. Eligibility will be determined by alcohol-consumption patterns and relevant health criteria. The project uses an experimental, translational design that integrates laboratory-based neuroscience measures with clinically meaningful behavioural outcomes.

Significance

This study addresses a central neurocognitive feature of addiction: dysregulated reward processing. It will test whether non-invasive neuromodulation can alter the relative valuation of alcohol-related cues and alternative rewards, and whether these neural changes are associated with reduced alcohol consumption. Demonstrating that tDCS can modify electrophysiological markers of reward processing and influence alcohol-related behaviour would provide important evidence for its potential as a targeted intervention for problematic alcohol use. The findings may help refine mechanistically informed approaches to reducing heavy drinking and preventing relapse.

Neuromodulation | NeuroAdx Lab