• Inhibiting effects of theanine on caffeine stimulation evaluated by EEG in the rat
  • “…Next, the stimulatory effects of caffeine were inhibited by an i.v. administration of theanine at a level higher than 5 micromol/kg (0.781 mg/kg) b.w., and the results suggested that theanine has an antagonistic effect on caffeine’s stimulatory action at an almost equivalent molar concentration.”
• Preventive effect of theanine intake on stress-induced impairments of hippocamapal long-term potentiation and recognition memory
• Protective effect of l-theanine on chronic restraint stress-induced cognitive impairments in mice
• Anti-Stress, Behavioural and Magnetoencephalography Effects of an L-Theanine-Based Nutrient Drink
• Effects of chronic l-theanine administration in patients with major depressive disorder: an open-label study
  • “…Our study suggests that chronic (8-week) l-theanine administration is safe and has multiple beneficial effects on depressive symptoms, anxiety, sleep disturbance and cognitive impairments in patients with MDD.”
• Theanine-induced Reduction of Brain Serotonin Concentration in Rats
• Effects of theanine on monoamine neurotransmitters and related genes in cerebral ischemia-reperfusion injury rats
  • Theanine Both Reduces Serotonin And Increases Dopamine