Increased power spectral density in resting-state pain-related brain networks in fibromyalgia.
By Ji -Young Kim, et al.
Fibromyalgia (FM), characterized by chronic widespread pain, is known to be associated with heightened responses to painful stimuli and atypical resting state functional connectivity among pain-related regions of the brain. Previous studies on FM using resting-state functional magnetic resonance imaging (rs-fMRI) have focused on intrinsic functional connectivity, which maps the spatial distribution of temporal correlations among spontaneous low frequency fluctuation (LFF) in fMRI resting-state data.
In the current study, using rs-fMRI data in frequency domain, we investigate the possible alteration of power spectral density (PSD) of low frequency fluctuation in brain regions associated with central pain processing in patients with FM.
Resting-state fMRI data were obtained from 19 patients with FM and 20 age-matched healthy female control subjects. For each subject, the PSDs for each brain region identified from functional connectivity maps were computed for the frequency band of 0.01-0.25 Hz. For each group, average PSD was determined for each brain region and a two-sample t-test was performed to determine the difference in power between the two groups.
According to the results, patients with FM exhibited significantly increased frequency power in the primary somatosensory cortex (S1), supplementary motor area (SMA), dorsolateral prefrontal cortex (DLPFC), and amygdala.
In patients with FM, the increase in PSD did not show an association with depression or anxiety. Therefore, our findings of atypical increased frequency power during resting-state in pain-related brain regions may implicate the enhanced resting-state baseline neural activity in several brain regions associated with pain processing in FM.
Source: Pain, May 25, 2013. By Ji -Young Kim, Seong-Ho Kim, Jeehye Seo, Sang-Hyon Kim, Seung Woo Han, Eon Jeong Nam, Seong-Kyu Kim, Hui Joong Lee, Seung-Jae Lee, Yang-Tae Kim, and Yongmin Chang. Department of Medical Science, Kyungpook National University School of Medicine, Daegu, Korea.