Two distinctive brain correlates for top-down regulation of heart rate induced by acupuncture
Poster No:
2630
Submission Type:
Abstract Submission
Authors:
CHANGJIN JUNG1, Kyungmo Park2
Institutions:
1KIOM, Daejeon, Korea, Republic of, 2Kyung Hee University, Yongin, Korea, Republic of
First Author:
Co-Author:
Introduction:
Increasing studies with acupuncture have demonstrated both heart rate (HR) acceleration and deceleration, which may associate homeostatic mechanism of autonomic nervous system (LI, 2022). Even within repeated identical stimuli of an acupuncture protocols, phasic HR responses demonstrated discrepancy, suggesting a top-down interference to low-level regulation of HR. Existing findings consolidates the top-down regulatory mechanisms of heart rate, including orienting, arousal, affective, social, and cognitive responses (THAYER, 2009). However, underpinning linkages between these regulatory mechanisms and acupuncture remain unclear.
Acupuncture is a compound interventional procedure including two components such as invasive needle stimulation and contextual manipulation for treatment. Here, we hypothesized that these two components would induce different brain mechanisms, contributing to HR changes. For instance, acupuncture stimuli to skin surface induce somatosensory afference accompanied by involuntary attention on body (i.e. orienting response). While, contextual manipulation for acupuncture treatment attracts voluntary attention on body (i.e. cognitive process). In present study, we aimed to investigate top-down regulatory mechanisms of HR differently induced by these two components of acupuncture.
Acupuncture is a compound interventional procedure including two components such as invasive needle stimulation and contextual manipulation for treatment. Here, we hypothesized that these two components would induce different brain mechanisms, contributing to HR changes. For instance, acupuncture stimuli to skin surface induce somatosensory afference accompanied by involuntary attention on body (i.e. orienting response). While, contextual manipulation for acupuncture treatment attracts voluntary attention on body (i.e. cognitive process). In present study, we aimed to investigate top-down regulatory mechanisms of HR differently induced by these two components of acupuncture.
Methods:
Participants received electrical stimuli via inserted needle on the upper lateral side at the left leg (ST-36) for the somatosensory afferent (Sa) and/or visual cue informing the contextual manipulation (Cm) for treatment during fMRI scan. In REAL session (n = 23), both Sa and Cm were simultaneously conducted. In ZOMB session (n = 23), Sa were conducted; but we informed participants that an electrical diagnostic measurement would perform with the visual cue. In PHNT session (n = 18); there was no Sa; but participants received visual cue for contextual manipulation. In CONT session (n = 21), non-meaningful visual cue without Sa was performed for the control condition. Thus, we used two-by-two factorial design for two components of acupuncture. During the scan we acquired photoplethysmography to assess HR.
We divided each fMRI data into 15 samples along the timeseries, corresponding to period of each stimulus interval. Then, whole samples (n = 1260) were merged to perform tensor-independent component analysis (tICA), which produces three matrices for spatial maps of ICs, timeseries and estimated scores of ICs for the samples. In accordance with the two-by-two factorial design, three-way ANOVA with interaction terms was performed for the estimated scores of each IC with Sa, Cm, and HR factors. We assessed interaction effects between Sa/Cm and HR factors representing Sa/Cm-specific association with HR (SaHR/CmHR). Since the spatial maps of ICs depended on the dimensionality of IC, we assessed statistic power of SaHR and CmHR for all possible dimensionality of IC. We identified the optimized dimensionality at 6 for our hypothesis (2nd IC for SaHR [IC-SaHR], p < 0.01; 1st IC for CmHR [IC-CmHR], p < 0.01).
We divided each fMRI data into 15 samples along the timeseries, corresponding to period of each stimulus interval. Then, whole samples (n = 1260) were merged to perform tensor-independent component analysis (tICA), which produces three matrices for spatial maps of ICs, timeseries and estimated scores of ICs for the samples. In accordance with the two-by-two factorial design, three-way ANOVA with interaction terms was performed for the estimated scores of each IC with Sa, Cm, and HR factors. We assessed interaction effects between Sa/Cm and HR factors representing Sa/Cm-specific association with HR (SaHR/CmHR). Since the spatial maps of ICs depended on the dimensionality of IC, we assessed statistic power of SaHR and CmHR for all possible dimensionality of IC. We identified the optimized dimensionality at 6 for our hypothesis (2nd IC for SaHR [IC-SaHR], p < 0.01; 1st IC for CmHR [IC-CmHR], p < 0.01).
Results:
HR demonstrated both acceleration and deceleration in the experimental protocols (REAL: 62% decelerations; ZOMB: 59% decelerations; PHNT: 49% decelerations; CONT: 50% decelerations). The significant HR decelerations showed for REAL (p < 0.00001) and ZOMB (p < 0.0001).
Spatial map of IC-SaHR showed functional couplings for facilitations in inferior frontal gyrus and visual cortex; and inhibitions in cingulate cortex, anterior insular, and somatosensory cortex. While, spatial map of IC-CmHR showed functional couplings for facilitations in anterior insular and dorsolateral prefrontal cortex; and inhibitions in default mode network (DMN) (Fig. 1).
Spatial map of IC-SaHR showed functional couplings for facilitations in inferior frontal gyrus and visual cortex; and inhibitions in cingulate cortex, anterior insular, and somatosensory cortex. While, spatial map of IC-CmHR showed functional couplings for facilitations in anterior insular and dorsolateral prefrontal cortex; and inhibitions in default mode network (DMN) (Fig. 1).
·Figure 1. Top-down heart rate (HR) regulatory mechanisms, differently induced by two components of acupuncture.
Conclusions:
The HR decelerations could be associated with suppression of coordinated inhibitions in cingulate cortex, anterior insular, and somatosensory cortex. Inhibition of DMN could decelerate HR.
Perception, Attention and Motor Behavior:
Perception: Tactile/Somatosensory 2
Physiology, Metabolism and Neurotransmission :
Physiology, Metabolism and Neurotransmission Other 1
Keywords:
Cognition
FUNCTIONAL MRI
Somatosensory
Other - acupuncture, heart rate
1|2Indicates the priority used for review
Provide references using author date format
THAYER, J. F.; LANE, R. D. Claude Bernard and the heart-brain connection: further elaboration of a model of neurovisceral integration. Neurosci Biobehav Rev, 33, n. 2, p. 81-88, Feb 2009.