An arterial spin-labeled magnetic resonance imaging study of brain activation in patients with major depressive disorder during acupuncture stimulation: An exploratory study

BACKGROUND: Acupuncture has demonstrated antidepressant efficacy; however, the brain's immediate response to stimulation in patients with major depressive disorder (MDD) remains unclear. We investigated cerebral blood flow (CBF) dynamics during and after acupuncture in patients with MDD via arterial spin labeling (ASL)-MRI. METHODS: Eleven patients with recurrent MDD and 14 healthy controls (HCs) underwent ASL-MRI at baseline, during, and after acupuncture (LI4, PC6, ST36, LV3). As an exploratory study, absolute CBF changes were analyzed using a flexible factorial design (voxelwise uncorrected P 〈 0.01; cluster-size 〉 350 voxels). RESULTS: In patients with MDD, acupuncture elicited increased CBF in the postcentral and prefrontal regions, with sustained activation in the middle frontal gyrus (DLPFC) poststimulation. Conversely, CBF decreased in the amygdala and posterior cingulate cortex following stimulation. Compared with HCs, patients with MDD exhibited a distinct neural perfusion pattern characterized by significantly greater recruitment of somatosensory-cognitive networks and attenuated activation in emotion-memory circuits. CONCLUSION: Acupuncture elicited distinct perfusion responses in MDD, shifting from maladaptive limbic dominance toward enhanced prefrontal engagement. These findings suggest that acupuncture stimulation is associated with perfusion patterns consistent with potential modulation of limbic-cortical networks in MDD.