Source density analysis of EEG recordings from 12 healthy human volunteers was used in a randomized, placebo controlled cross over study to investigate the change in physiological parameters after ingestion of a soft drink containing green tea extract enriched with L-theanine and theogallin. EEG was recorded 1, 2, 3 and 4 h after ingestion during different recording conditions. Visually evoked P300 potentials were recorded every hour in addition to the EEG recordings. Analysis of the data revealed a general attenuation of electrical delta power under the condition of eyes open during the first hour (statistically significant at p < 0.01). During a reading test increases of delta and theta power were observed at frontal electrode sites starting with the second hour after administration, significant at the third and fourth hour (p < 0.04) in comparison to placebo. These changes indicate a higher level of mental performance. Increases of beta 1 power starting with the second hour indicated a higher degree of relaxation. However, no statistical significance was reached. Analysis of visually evoked P300 waves revealed a decrease in latency at the last hour (statistical significance p < 0.04) as well as increases of amplitudes at the electrode position Cz (from the first to the third hour, statistically not significant). This type of result in general suggests an improvement of attention. Thus, decaffeinated extract of green tea still has a stimulating effect despite the lack of caffeine presumably due to its high content in L-theanine and theogallin as found in preclinical experiments.

Functional food products should provide scientifically proven beneficial effects in healthy subjects. The highly sensitive method of EEG recording from healthy human volunteers was used in a randomized, placebo controlled crossover study to investigate the effects of a change in physiological parameters after ingestion of a total of 750 ml of a softdrink containing 0.232 g of ginseng and 2 g of ginkgo extract, both produced by water extraction. Application of a random, placebo controlled crossover design was done with 10 healthy male volunteers. EEG recordings were performed 1, 2, 3 and 4 h under the conditions of 10 min eyes open, 5 min eyes closed and 5 min reading short stories. Auditory P300 potentials were recorded every hour in addition to the EEG recordings. Source density analysis of the data revealed an attenuation of circadian induced electrical delta power decreases under the condition of eyes open and closed recording from centro-parieto-occipital electrode positions. During a reading test even absolute increases of delta power were observed at these electrode sites. These changes were statistically significant at p < 2% for the second hour (eyes open and reading) and are interpreted to indicate a higher degree of emotional well-being. Decreases in latency (from 333.9 to 321.3 ms) as well as increases of amplitude (from 2.07 to 3.95 microV) of the auditory P300 potential at the electrode position Pz point to a possible improvement of attention, however, the difference did not reach statistical significance.

Background: The current and potential uses of adaptogens are mainly related to treatment of stress-induced fatigue, impaired cognitive function, mental illness, and behavioral- and age-related disorders. However, clinical evidence regarding the efficacy of adaptogens is limited. The primary aim of this study is to determine whether a combination of adaptogenic plant extracts from Andrographis paniculata and Withania somnifera (Adaptra® Forte) could be used as effective and safe treatment for impaired cognitive, memory, or learning ability functions and sleep disorders. Methods: The changes in electroencephalogram (EEG) frequency ranges in 17 different brain regions, psychometric tests of cognitive performance, as well as standard questionnaires of assessment of mood and sleep were measured after single and repeated administration of Adaptra® or placebo for four weeks and after a two-week treatment-free follow-up period within a randomized, double-blind, placebo-controlled two-armed cross-over study. Results: Adaptra® Forte significantly improved cognitive performance in the d2-Test for attention and the concentration performance test after four weeks’ treatment, and was positively correlated with increases in δ and θ power in the quantitative EEG compared with placebo during cognitive challenges. Conclusion: The results of this study suggest that Adaptra® Forte exhibits a calming and anxiolytic effect without sedation, and is associated with overall stress-protective activity.