Hemispheric divergence of interoceptive processing across psychiatric disorders.

Area of Science:

• Neuroscience
• Psychiatry
• Cognitive Science

Background:

• Conscious interoception integrates top-down attention and bottom-up bodily signals.
• Aberrant interoceptive symptoms are common in psychiatric disorders, but the neural basis is unclear.
• The insular cortex is a potential hub for processing interoceptive information.

Approach:

• A preregistered functional neuroimaging study compared individuals with anxiety, depression, and/or eating disorders (ADE) to healthy controls (HC).
• Two tasks were used: an interoceptive attention task (top-down) and an isoproterenol infusion task (bottom-up).
• Neural activity and functional connectivity within the insula were analyzed.

Key Points:

• Neural activation converged in the bilateral insular cortex, particularly the granular and ventral dysgranular subregions.
• The ADE group showed asymmetric insula activation patterns compared to HCs.
• Reduced anterior insula activation was observed in the ADE group during bodily uncertainty.

Conclusions:

• The dysgranular mid-insula serves as a critical interface for integrating attention and bodily inputs.
• Asymmetric insula activation and connectivity alterations may underlie interoceptive dysfunction in psychiatric disorders.
• The mid-insula represents a potential neural locus for disruptions in psychiatric conditions.