Can Valerian root extracts alter functional brain connectivity?
While four weeks of supplementation with valerian root extract (Natural F&P Inc., South Korea) did not produce any significant differences with placebo for all the clinical scales used, there were significant differences between the groups when it came to EEG [electroencephalography] scores.
Scientists from Hallym University College of Medicine in Korea found that valerian root extract supplementation led to increased coherence in the frontal brain region associated with neurophysiological integration, cognitive flexibility, and information processing.
“Consistent with our findings, frontal EEG coherence is reportedly inversely correlated with both state and trait anxiety and somatic anxiety,” wrote the researchers in Phytotherapy Research. “The relationship between strengthened connectivity and anxiolysis implies that valerian‐induced increases in cortical information exchange can relieve anxiety in stressed individuals.”
Valerian root
Valerian (Valeriana officinalis) is most commonly associated with formulations that enhance sleep, but data does support potential activity for alleviating anxiety, depression, and psychological stress, according to background information in the new paper.
The new study included 64 people with psychological stress, randomly assigned to one of two groups: One group received daily supplements of valerian root extract (300 mg), and the other group received placebo.
The results showed that, while no changes were observed for the clinical scales, EEG data looking at coherence values in the alpha (8–12 Hz) and theta (4–8 Hz) bands showed increases in alpha coherence and decreases in theta coherence for the valerian group, versus placebo.
“[A]lpha and theta power activities are linked to decreased anxiety and emotional arousal,” explained the researchers.
The study was said to be the first to assess the potential neurophysiological effects on brain connectivity of valerian in non-clinical people.
“These findings suggest that although no VRE [valerian root extract] effect could be detectable by psychological measures, neurophysiological measures might capture Valerian's beneficial effect on the brain,” wrote the researchers.
“EEG coherence, which reflects functional brain connectivity, appears to be a promising biological index of VRE's effects. Further neurophysiological studies with various methods such as resting‐state EEG or event‐related potential measurements are needed to confirm valerian's benefits.”
Source: Phytotherapy Research
Published online ahead of print, doi: 10.1002/ptr.6286
“Valerian extract alters functional brain connectivity: A randomized double‐blind placebo‐controlled trial”
Authors: D. Roh, et al.
