Widespread brain–body integration during changes of arousal by Widespread, slow fuctuations instant download

Widespread brain–body integration during changes of arousal by Widespread, slow fuctuations instant download

The problemanalysis of the spatiotemporal patterns of global fMRI signals in resting-state condiWidespread or ‘global’ fluctuations in brain tions revealed a characteristic sequence of blood flow are a pervasive feature of funcchanges across the gray matter, white matter tional MRI (fMRI) recordings. The origin and and ventricles of the brain. Together, we integration functional relevance of fluctuations in this concluded that global fMRI fluctuations in ‘global signal’ is a subject of considerable the brain are associated with systemic physidebate in the fMRI community1. One clue is ological changes across the body.during given by the global signal’s frequent appearance during changes in cortical and physichanges of ological arousal organized by the autonomic The interpretationnervous system (ANS), as measured by electroencephalography (EEG) and periphOur findings suggest that global fluctuations arousaleral physiology (such as respiration and in brain blood flow and electrical activity photoplethysmography (volumetric blood are an integral component of the arousal changes)), respectively2. These findings sugresponse organized by the ANS. These gest a much tighter integration of the brain’s observations also highlight how global fMRI vascular and neural activities with the operaeffects — even those of non-neuronal origin tions of the ANS than has heretofore been (such as vascular mechanisms) — can provide acknowledged. The purpose of our study valuable indicators of physiological state.Widespread, slow fuctuations was to examine the degree to which vascular Our research leaves ope(global fMRI signal) and neural (EEG) signals that mediate the associatiin brain blood fow detected in the brain are integrated with the body’s ANS arousal response andvia functional MRI and neural physiological dynamics (such as pupil fluctuations. Sympatheticactivity are integrated with diameter, heart rate and vascular tone),