Neurovascular dysregulation in the thalamic-temporo-occipital axis is linked to emotional blunting and visual imagery deficits in depression.

BACKGROUND

Depression is characterized by clinical features such as emotional blunting and reduced vividness of visual mental imagery. Impaired neurovascular coupling (NVC) may represent a shared pathophysiological mechanism linking these symptoms. However, this potential connection remains unexplored.

METHODS

A cohort of 117 participants (59 depressed patients, 58 healthy controls) completed the PHQ-9, HAMD-17, Vividness of Visual Imagery Questionnaire (VVIQ), and Emotional Contagion Scale (ECS), and underwent rs-fMRI, ASL, and dynamic cerebral autoregulation (dCA). Neurovascular regulation was quantified using CBF-fALFF signals. Analyses included group comparisons, functional connectivity mapping, mediation modeling.

RESULTS

Depressed patients demonstrated reduced imagery vividness and lower ECS scores for happiness/love contagion. VVIQ scores were positively correlated with positive emotional contagion in patients with depression. Neuroimaging revealed neurovascular dysregulation in temporal and occipital regions. Concurrently, left-hemisphere dCA impairment was observed and correlated with occipital neurovascular abnormalities. Enhanced functional connectivity emerged between temporo-occipital regions and bilateral thalamus, with thalamic neurovascular signals mediating the relationship between visual imagery vividness and positive emotion contagion.

CONCLUSION

This study suggests that thalamic-temporo-occipital neurovascular axis may be the mechanistic basis for emotional blunting and visual imagery deficits in depression.