Green tea extract combined with L-theanine stimulates memory

In a randomized study, 91 subjects with mild cognitive impairment, a risk factor for Alzheimer's disease, received either an extract combining green tea and l-theanine, or a placebo, over 16 weeks. Tests were conducted to evaluate memory and attention.
Results showed memory improvements in those who received the green tea/l-theanine extract, with marginal improvements to delayed recognition and significant increases in memory of word reading. Electroencephalograms conducted on 24 subjects showed improvements in indicators of mental alertness in specific parts of the brain.
(Journal of Medicinal Food, Volume, Issue 4, pages 334-343)