The effects of cue-induced craving on brain oscillations in alcohol use disorder patients: an electroencephalography study

Aims

Cue-induced craving is a central mechanism underlying relapse vulnerability in alcohol use disorder (AUD), as alcohol-related cues can activate conditioned motivational processes even during abstinence. However, the temporal neural dynamics of cue reactivity remain poorly characterized. Electroencephalography (EEG), with its high temporal resolution, enables examination of oscillatory activity related to attentional and motivational salience. Previous EEG studies in AUD have mainly focused on resting-state activity, consistently reporting elevated beta power and associations with relapse risk [1,2]. Direct investigations of alcohol cue reactivity are relatively scarce. Although increased frontal beta responses to alcohol-related stimuli have been described [3], prior studies were limited by cross-sectional designs, restricted electrode coverage, and the absence of longitudinal follow-up. Accordingly, the present study aimed to characterize regional and frequency-specific EEG responses to alcohol-related cues in individuals with AUD, examine their associations with clinical symptoms, and evaluate longitudinal changes at follow-up.

Methods

Thirty inpatients with AUD (20–65 years) were recruited from the Ankara University Department of Psychiatry after medically assisted withdrawal. Participants underwent 64-channel EEG during exposure to alcohol-related (positive) and neutral visual stimuli in a within-subject design. Clinical assessments included CIWA-Ar, Beck Anxiety and Depression Inventories, Alcohol Dependence Severity Scale, Yale–Brown Obsessive–Compulsive Drinking Scale (heavy drinking version), and the Penn Alcohol Craving Scale (PACS). Subjective craving was measured using a Visual Analogue Scale (VAS) before and after cue exposure. EEG data were analyzed using fast Fourier transform to compute spectral power in delta (0–4 Hz), alpha (8–13 Hz), early beta (13–20 Hz), late beta (20–30 Hz), and gamma (30–40 Hz) bands. Repeated-measures ANOVA included region (six levels), hemisphere (left, right, midline), and cue type (positive, neutral) as within-subject factors, with Greenhouse–Geisser correction and Tukey-adjusted post-hoc tests. Normality was assessed using the Shapiro–Wilk test; analyses included paired t tests for VAS and Pearson correlations between clinical scores and EEG changes. Eight participants completed a six-week follow-up (T1), allowing preliminary longitudinal evaluation.

Results

At T0, no significant differences were observed between alcohol-related and neutral cues in the lower-frequency bands (delta, theta, alpha, early beta). In contrast, high-frequency oscillations were more sensitive to stimulus content. Late beta activity showed a frontopolar increase during alcohol-related cue exposure that did not survive multiple-comparison correction, whereas gamma activity was significantly higher for alcohol-related cues, particularly in frontopolar, parietal, and occipital regions. At follow-up (T1), alcohol-related cues continued to elicit relatively greater late beta and widespread gamma activity. Longitudinal analyses indicated attenuation of cue-related gamma differences over time, especially in central and parietal–occipital regions. Gamma changes were negatively correlated with PACS scores, such that individuals with higher baseline craving exhibited smaller longitudinal increases, consistent with a possible ceiling effect.

Conclusions

Alcohol-related cues elicited localized increases in high-frequency activity, particularly in the gamma band, reflecting motivational salience and frontal regulatory engagement. Attenuation of cue-related differences over time suggests treatment-related neurophysiological modulation. These findings support the utility of EEG in capturing frequency-specific neural dynamics of cue-induced craving in AUD.

References

1. Herrera-Díaz, A., Mendoza-Quiñones, R., Melie-Garcia, L., Martínez-Montes, E., Sanabria-Diaz, G., Romero-Quintana, Y., et al., 2016. Functional connectivity and quantitative EEG in women with alcohol use disorders: A resting-state study. Brain Topogr. 29, 368–381.
2. Bauer, L.O., 2001. Predicting relapse to alcohol and drug abuse via quantitative electroencephalography. Neuropsychopharmacology 25 (3), 332–340.
3. Kim, J., Nam, S., Kim, D.H., Lee, S.-K., Jung, H.W., Kim, C.-H., et al., 2023. Frontal EEG response to alcohol craving elicited by individually tailored video cues. Alcohol 112, 1–7.