Where alcohol use disorder meets interoception: A meta-analytic view on structural and functional neuroimaging data

Area of Science:

• Neuroscience
• Psychiatry
• Addiction Research

Background:

• Alcohol use disorder (AUD) is linked to altered interoception, the processing of internal body signals.
• Brain structural changes, especially in the insula, are hypothesized to cause impaired interoception in AUD.
• Limited research directly investigates the association between AUD-related gray matter reduction and interoception deficits.

Purpose of the Study:

• To compare meta-analytic findings on interoception with recent meta-analytic results on gray matter reduction in AUD.
• To identify the functional brain network associated with interoception and its overlap with AUD-related structural changes.

Main Methods:

• Systematic literature search identifying 25 interoception studies.
• Activation Likelihood Estimation (ALE) for spatial convergence of interoception results.
• Conjunction analysis to test overlap between interoception and AUD clusters.
• Meta-Analytic Connectivity Modeling (MACM) and resting-state functional connectivity to map interoception networks.
• Behavioral domain analysis to characterize functional profiles of overlapping clusters.

Main Results:

• ALE identified an interoception cluster in the left middle insula, with no direct overlap with AUD gray matter reduction clusters.
• MACM and resting-state analyses revealed a broad interoception network involving insulae, thalami, basal nuclei, and cortical areas, strongly connected to salience and somatomotor networks.
• Five of eight AUD gray matter reduction clusters were located within these identified interoception networks, associated with salience control, somatomotor functions, and skin sensations.

Conclusions:

• Results suggest altered salience mapping of interoceptive signals in AUD, impacting action control and sensory integration.
• The findings support targeting interventions towards the salience and somatomotor networks to address interoceptive deficits in AUD.
• Potential interventions include mindfulness, pleasurable touch, and transcranial magnetic stimulation to reduce AUD and prevent relapse.