Brain Responses to Acupuncture Are Probably Dependent on the Brain Functional Status

Abstract

In recent years, neuroimaging studies of acupuncture have explored extensive aspects of brain responses to acupuncture in finding its underlying mechanisms. Most of these studies have been performed on healthy adults. Only a few studies have been performed on patients with diseases. Brain responses to acupuncture in patients with the same disease at different pathological stages have not been explored, although it may be more important and helpful in uncovering its underlying mechanisms. In the present study, we used fMRI to compare brain responses to acupuncture in patients with Bell's palsy at different pathological stages with normal controls and found that the brain response to acupuncture varied at different pathological stages of Bell's palsy. The brain response to acupuncture decreased in the early stages, increased in the later stages, and nearly returned to normal in the recovered group. All of the changes in the brain response to acupuncture could be explained as resulting from the changes in the brain functional status. Therefore, we proposed that the brain response to acupuncture is dependent on the brain functional status, while further investigation is needed to provide more evidence in support of this proposition.

Functional Connectivity Changes of Primary Somatosensory Cortex in Response to the Acupuncture in Bell’s Palsy Patients

“…We contrasted their alterations in connectivity and the results showed that the alterations were more obvious in contralateral acupoint group even though the direct activation area of contralateral acupuncture was in the non-lesioned side. It was in accordance with clinical result that contralateral acupuncture has stronger therapeutic effect [10,13]. Our results suggested that acupuncture might improve functions of the lesioned side brain by stimulating non-lesioned side brain.…”

“…It has been verified that the acupuncture played an important role in ameliorating the blepharospasm in non-lesioned side [15,16]. We suggested that the alteration in non-lesioned side SI connectivity might be the result of reductions of the abnormal brain activity tendencies [5,10].…”

“…Our previous studies have also shown that the acupuncture leads to significant connectivity change. In addition, several investigations suggest the brain's responses to acupuncture depend on the functional connectivity status and that some functional reorganizations of special cortical regions are important in the process of BP recovery [5,9,10]. Thus, we believed that different effects of acupuncture made on the bilateral Hegu points would be revealed by comparing functional connectivity alterations.…”

Mechanisms of Acupuncture–Electroacupuncture on Persistent Pain

“…Electroacupuncture intervention activates the nervous system differently in health than in pain, as shown by the fact that opioid receptors are differentially involved in electroacupuncture inhibition of pain in healthy animals and those with persistent pain (table 2), as well as by the brain responses to acupuncture displayed by patients with Bell’s palsy compared to those of healthy volunteers. 183 Moreover, electroacupuncture parameters affect outcomes: 10 Hz electroacupuncture produces longer lasting alleviation of inflammatory pain than does 100 Hz, and 2–10 Hz inhibit nerve injury-caused allodynia/hyperalgesia more potently than does electroacupuncture at 100 Hz.…”

“…Indeed, it has been shown that patients with Bell’s palsy have distinct brain responses to acupuncture treatment compared to healthy volunteers. 183 Further, patients at different stages of Bell’s palsy varied in brain responses to acupuncture. Taken together, electroacupuncture alleviates visceral pain by modulating spinal and DRG activities through endogenous opioids.…”