Investigation of Acupuncture-specific BOLD Signal Changes Using Multiband Acquisition and Deconvolution Analysis

Area of Science:

• Neuroimaging
• Neuroscience
• Medical Acupuncture

Background:

• The blood oxygen level-dependent (BOLD) signal reflects neural activity, but its temporal dynamics are complex.
• Understanding BOLD signal responses to different stimuli is crucial for interpreting neuroimaging data.

Purpose of the Study:

• To investigate the temporal dynamics of BOLD signal responses to real acupuncture, sham acupuncture, and palm scrubbing.
• To analyze brain responses using deconvolution analysis with multi-band (MB) echo-planar imaging (EPI) for improved time resolution.

Main Methods:

• 26 healthy adults were divided into real acupuncture (n=13) and sham acupuncture/palm scrubbing (n=13) groups.
• Multi-band echo-planar imaging (MB-EPI) and deconvolution analysis were employed to measure BOLD signal responses.
• Stimulus-specific impulse responses were analyzed without a predefined reference function.

Main Results:

• Real acupuncture showed distinct BOLD signal patterns, including delayed and sustained increases in areas like the anterior cingulate cortex (ACC) and thalamus.
• Sham acupuncture and palm scrubbing elicited different BOLD responses, primarily during stimulation.
• Activated regions included the secondary somatosensory cortex (SII), insula, and primary somatosensory cortex (SI) depending on the stimulus.

Conclusions:

• Delayed and long-sustained BOLD signal increases observed with real acupuncture may be linked to peripheral nociceptors, flare responses, and central nervous system processing.
• Deconvolution analysis with MB-EPI successfully identified BOLD signal changes related to pain perception specific to real acupuncture.
• These findings contribute to understanding the therapeutic mechanisms of acupuncture.