Frontal and temporo-parietal changes in delta and alpha power accompany stress-induced vasoconstriction and blood pressure response

Abstract

Exaggerated blood pressure and vasoconstriction responses during acute mental stress are prospectively associated with an increased risk of hypertension, arrhythmia, and vascular dysfunction. This study assessed electrophysiological brain power and cardiovascular response to acute psychological stress during concurrent recordings of magnetoencephalography, muscle sympathetic nerve activity, and blood pressure in 29 healthy participants. Brain power was filtered through delta (1-4 Hz), theta (4-8 Hz), alpha (8-13 Hz), beta (13-30 Hz), low gamma (30-80 Hz), and high gamma (80-120 Hz) bands. Stress induced significant increases in systolic blood pressure (SBP), 5.2 ± 5.6 mmHg, heart rate, 4.1 ± 4.8 beats/min, and sympathetic nerve activity, 4.0 ± 8.0 bursts per minute (means ± SD, P < 5). Whole head and region of interest analyses showed stress induced significant increases in delta power in the right medial frontal cortex, anterior cingulate, and amygdala. Alternatively, there were significant decreases in alpha power in the left and right precuneus, posterior cingulate, hippocampus, and in the right thalamus and insula. Correlation analyses revealed that reduced alpha power in the right insula was correlated with SBP (r = 0.446). Moreover, reduced alpha power in the left amygdala was correlated with SBP (r = 0.392), anxiety, and depression inventory scores, P < 0.01. The reduced alpha power in the insula and amygdala was pronounced in participants displaying heightened sympathetic nerve reactivity to stress. Similarly, participants who displayed higher mean SBP reactivity (of 19 mmHg) to stress showed reduced alpha power in the precuneus, hippocampus, and amygdala. Our results suggest that regionalized and frequency-specific brain power is involved in neurogenic blood pressure regulation in normotensive individuals.NEW & NOTEWORTHY This study illustrates a correlation between electrophysiological brain power, sympathetic nerve activity, and blood pressure in response to stress. Notable mental stress-induced changes were observed, including an increase in delta power in the frontal regions and a decrease in alpha power in the temporal and parietal regions. The diminished alpha power in the insula, amygdala, precuneus, and hippocampus was particularly significant among individuals exhibiting greater vasoconstrictor activity and a higher increase in systolic blood pressure.

Keywords: blood pressure; cardiovascular; magnetoencephalography; neuroimaging; stress.