042). Twenty-two percent of the variance in rs-fc between right anterior insula and periaqueductal gray was attributed to CM years while 21% of the variance was attributable to state anxiety. The main study finding is the presence of atypical rs-fc of affective pain regions in interictal CM. Themes emerging from this study include: (1) identification
of interictal atypical rs-fc supports the notion that CM has persistent manifestations between migraine attacks; (2) atypical functional connections with affective pain regions involve regions that participate in multiple domains of the pain experience, including sensory-discriminative, cognitive, modulating, and integrative domains; (3) atypical rs-fc find more between affective pain-processing regions with middle temporal cortex and with the pulvinar may relate to intolerance to sound and light, the two key characteristics of migraine. Although migraine is often considered a chronic disorder with episodic manifestations, there is increasing evidence that migraine has manifestations that persist between attacks (ie, interictally). Evidence for this argument comes from the imaging of the migraine brain, as well as physiological studies.[5-7, 48, 49] Many of the atypical imaging and physiological findings in migraineurs positively associate with longer disease duration and/or more frequent migraine attacks, suggesting a causal relationship. Furthermore, Selleckchem Smoothened Agonist migraineurs
recognize and report interictal migraine manifestations. Interictal visual hypersensitivity to light (photophobia) is reported by ∼45% of migraineurs and interictal sound hypersensitivity (phonophobia) by ∼75%.[6, 50] This rs-fc study supports the argument that CM is associated with atypical interictal brain function, specifically atypical rs-fc between affective pain-processing regions and regions participating in other aspects of the pain experience. Longitudinal studies are needed to determine if these interictal manifestations are secondary to repeated migraine attacks or if they represent underlying aberrations in the migraineur’s brain that predispose to migraine. selleck products In this
study, CM subjects had rs-fc to affective pain regions that differed from control subjects in several ways depending upon the specific functional connection: (1) positive temporal correlation in control and no correlation in CM (eg, left anterior insula with right precuneus); (2) negative correlation in control and no correlation in CM (eg, right anterior insula with left pulvinar); (3) negative correlation in control and positive correlation in CM (eg, left anterior insula with left middle temporal); (4) negative correlation in CM and no correlation in control (eg, right amygdala with left occipital). Stronger positive correlations and stronger negative correlations may both be associated with maximal processing efficiency. A stronger positive correlation between two regions suggests more frequent coactivation of those two regions.