Neurobiological Mechanisms of Alcohol Use Disorders

Alcohol use disorders arise from maladaptive neurobiological changes across reward, stress and executive-control circuits. Acute alcohol enhances inhibitory GABAergic transmission and inhibits excitatory glutamatergic signalling, while chronic exposure provokes compensatory adaptations in NMDA and GABA receptor expression. Within the mesolimbic dopamine system, repeated alcohol intake alters dopamine release in the ventral tegmental area and nucleus accumbens, reinforcing drug-seeking behaviour. Concurrent recruitment of brain stress systems—such as corticotropin-releasing factor and dynorphin within the extended amygdala—drives negative affect during withdrawal and promotes relapse. Emerging evidence highlights the role of neuroimmune pathways: alcohol-induced release of danger signals (for example, HMGB1) activates Toll-like receptors on microglia, engendering persistent neuroinflammation and synaptic dysregulation. Structural and functional changes in prefrontal cortex underlie impairments in cognitive flexibility and decision-making. Sex-specific variations in serotonergic and neuroendocrine responses further modulate risk trajectories. Together, these intertwined processes—neurotransmitter imbalance, stress system hyperactivity, neuroimmune activation and altered plasticity—constitute the neurobiological framework of alcohol use disorders and suggest multiple avenues for therapeutic intervention.

Research from Nature Portfolio

Recent studies have shown that binge alcohol consumption produces sex-specific adaptations in serotonergic circuits within subcortical regions. In mouse models, excessive intake potentiated 5HT2c receptor signalling in lateral habenula and bed nucleus of the stria terminalis neurons. Hyperactivation of lateral habenula 5HT2c-expressing cells was identified as a primary mechanism driving social recognition deficits in females and heightened sensorimotor arousal in males. These findings underscore the potential of targeting the serotonin 5HT2c receptor for tailored treatments addressing mood and alcohol use disorders according to biological sex.

Neurobiological Mechanisms of Alcohol Use Disorders publication trend

The graph below shows the total number of articles in neurobiological mechanisms of alcohol use disorders across all publications each year (not limited to Nature Index journals).

Technical terms

5HT2c receptor: A serotonin receptor subtype involved in modulating mood, arousal and alcohol-related behaviours.

Lateral habenula (LHb): A midbrain structure that processes aversive signals and influences reward circuits.

Bed nucleus of the stria terminalis (BNST): A limbic forebrain region that integrates stress and anxiety-related signals.

Corticotropin-releasing factor (CRF): A neuropeptide that coordinates the stress response and contributes to withdrawal-related negative affect.

Phosphodiesterase type 4 (PDE4): An enzyme that degrades cyclic AMP; its inhibition can modulate intracellular signalling to reduce alcohol intake.

Nucleus accumbens: A key component of the brain’s reward system that mediates motivation and reinforcement.

References

1. Subcortical serotonin 5HT2c receptor-containing neurons sex-specifically regulate binge-like alcohol consumption, social, and arousal behaviors in mice. Nature Communications (2023).
2. Chemogenetic inhibition of central amygdala CRF-expressing neurons decreases alcohol intake but not trauma-related behaviors in a rat model of post-traumatic stress and alcohol use disorder. Molecular Psychiatry (2024).
3. Pre-clinical and clinical evidence for suppression of alcohol intake by apremilast. Journal of Clinical Investigation (2023).
4. Microglial-derived miRNA let-7 and HMGB1 contribute to ethanol-induced neurotoxicity via TLR7. Journal of Neuroinflammation (2017).
5. Chronic Alcohol Exposure Alters Behavioral and Synaptic Plasticity of the Rodent Prefrontal Cortex. PLOS ONE (2012).