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Updated: May 25, 2026

Assessing Pupil-linked Changes in Locus Coeruleus-mediated Arousal Elicited by Trigeminal Stimulation
Published on: November 26, 2019
Clonidine-induced changes in the spectral distribution of heart rate variability correlate with performance on a test
H C Middleton1, J T Coull, B J Sahakian
1University of Cambridge Department of Psychiatry, Addenbrooke's Hospital, Hills Rd., Cambridge CB2 2QQ.
Abstract:
Conventional measures of cardiovascular activity correlate poorly with psychological variables and therefore provide imperfect physiological indices of arousal. We have investigated the effects of clonidine upon the spectral distribution of heart rate variability and upon performance on a test of sustained attention. Our findings suggest that activity of the central noradrenergic system influences the distribution of heart rate variability in the ~ 0.1 Hz range. Furthermore, the finding of a strong correlation between the effects of clonidine upon each of these variables supports the use of spectral analysis of heart rate variability in the study of arousal.
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