Source density analysis of the human EEG after ingestion of a drink containing decaffeinated extract of green tea enriched with L-theanine and theogallin.

AbstractSource 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 beta1 power starting with the second hour indicated a higher deg...