EEG markers of upright posture in healthy individuals

Abstract

The EEG spectral-coherence parameters were analyzed in 10 healthy individuals (mean age, 22 ± 0.67 years) at different steps of verticalization, from the lying position to the sitting and standing positions. The maximal changes in all EEG parameters were revealed when the upright posture was maintained in the absence of visual control. Under these conditions, a power increase for the fast EEG components (the β- and γ-bands) was observed, as was an additional increase when the conditions of maintaining the upright posture were complicated. According to the results of the EEG’s coherent analysis, human verticalization revealed a specific increase for most of the EEG rhythm ranges in the right hemisphere, especially in the frontocentral and occipitoparietal regions, as well as for the interhemispheric coherences for these leads reflecting the involvement of both cortical and subcortical structures in these processes. When the posture maintenance conditions were complicated, an additional coherence increase in the fast EEG bands (the β-rhythm) was observed in the frontal cortical regions, which was evidence of the increase in the executive functions under these conditions.