New research suggests that the astringent sensation caused by flavanols acts as a direct signal to the brain, triggering mild exercise-like effects on the nervous system.[content] In experiments on mice, flavanol intake increased activity, curiosity, learning and memory.[content][2][4] These compounds barely make it into the bloodstream.[content][4] The key is sensory stimulation, where the dry, bitter taste itself activates brain pathways associated with attention, motivation and stress response.[content][4] This lights up areas of the brain involved in arousal and memory.[content] Mice given flavanols an hour before the test performed 30% better in recognizing new objects than the control group.[2][4] This effect is related to an increase in noradrenaline in areas such as the locus coeruleus and nucleus accumbens.[2]