Effects of lozenge containing lavender oil, extracts from hops, lemon balm and oat on electrical brain activity of volunteers.

Within a randomized double blind, placebo controlled trial the electrical activity of the human brain has been monitored using charge mode technology (Laplacian estimates) after exposure to a lozenge containing 4 different herbal preparations (lavender oil, extracts from hops, lemon balm and oat) or a matching placebo without any active ingredients. Sixteen healthy volunteers (8 males and 8 females) were tested within a crossover design. After baseline recording each subject sucked a lozenge and 2 hours later a second one. Recording was performed immediately after finishing the lozenge and in hourly intervals thereafter. Comparison to reference periods of 10 min eyes open and 5 min eyes closed, respectively, revealed increases in alpha 1, alpha 2 and beta 1 electrical power at the electrode positions Cz, P3, T3 and T5 which were even more pronounced after a second application two hours later. Since alpha 1 changes repeatedly have been attributed to attentional states, increases of this electrical activity must be seen as indicator of a relaxational psychophysiological state. Changes in the alpha2 frequencies have been related to working memory indicating that an increase can be seen as a correlate for attenuating this circuit. Increases of beta1 activity have been seen in the presence of anxiolytic drugs including major and minor tranquilizers. The changes as observed after the application of this herbal composition are therefore in line with the idea of having induced a state of relaxation and regeneration. This interpretation suggests that one could expect from the ingestion of this lozenge to better cope with psychological and emotional stress. The data are further proof that recording computer aided quantitative EEG is a very fruitful and promising approach in psychophysiology.