A combination of caffeine and taurine has no effect on short term memory but induces changes in heart rate and mean arterial blood pressure

Summary.Red Bull energy drink has become extraordinarily popular amongst college students for use as a study aid. We investigated the combined effects of Red Bull’s two active ingredients, caffeine and taurine, on short term memory. Studies on the effects of these two neuromodulators on memory have yielded mixed results, and their combined actions have not yet been investigated. In this double-blind study, college student subjects consumed either caffeine and taurine pills or a placebo and then completed a memory assessment. Heart rate and blood pressure were monitored throughout the testing period. The combination of caffeine and taurine had no effect on short term memory, but did cause a significant decline in heart rate and an increase in mean arterial blood pressure. The heart rate decline may have been caused by pressure-induced bradycardia that was triggered by caffeine ingestion and perhaps enhanced by the actions of taurine.

[1]  M. Lin,et al.  Amino acids injected into the cerebroventricular system induce an enhancement of reflex bradycardia in the rat , 1983, Neuropharmacology.

[2]  Jennifer R. Redman,et al.  Effects of caffeine, time of day and user history on study-related performance , 2005, Psychopharmacology.

[3]  C. Alford,et al.  The effects of Red Bull Energy Drink on human performance and mood , 2001, Amino Acids.

[4]  H R Lieberman,et al.  The effects of ginseng, ephedrine, and caffeine on cognitive performance, mood and energy. , 2009, Nutrition reviews.

[5]  P. Rogers,et al.  Absence of reinforcing, mood and psychomotor performance effects of caffeine in habitual non-consumers of caffeine , 2003, Psychopharmacology.

[6]  K. Bättig,et al.  The effects of caffeine on physiological functions and mental performance , 1984, Experientia.

[7]  D. Kennedy,et al.  Cognitive and physiological effects of an “energy drink”: an evaluation of the whole drink and of glucose, caffeine and herbal flavouring fractions , 2004, Psychopharmacology.

[8]  H. Praag,et al.  Caffeine attenuates scopolamine-induced memory impairment in humans , 2005, Psychopharmacology.

[9]  Wing Hong Loke,et al.  Effects of caffeine on mood and memory , 1988, Physiology & Behavior.

[10]  D Robertson,et al.  Effects of caffeine on plasma renin activity, catecholamines and blood pressure. , 1978, The New England journal of medicine.

[11]  Evangelia Charmandari,et al.  Endocrinology of the stress response. , 2005, Annual review of physiology.

[12]  E. Bersellini,et al.  An evaluation of a caffeinated taurine drink on mood, memory and information processing in healthy volunteers without caffeine abstinence , 2001, Psychopharmacology.

[13]  D. Brackett,et al.  Caffeine enhances the physiological response to occupational stress in medical students. , 1987, Health psychology : official journal of the Division of Health Psychology, American Psychological Association.

[14]  R J Huxtable,et al.  Physiological actions of taurine. , 1992, Physiological reviews.

[15]  M. Baum,et al.  The influence of a taurine containing drink on cardiac parameters before and after exercise measured by echocardiography , 2001, Amino Acids.

[16]  W. Lovallo,et al.  Effects of caffeine on blood pressure response during exercise in normotensive healthy young men. , 1990, The American journal of cardiology.

[17]  L. Ryan,et al.  Caffeine Reduces Time-of-Day Effects on Memory Performance in Older Adults , 2002, Psychological science.

[18]  S. Oja,et al.  Phencyclidine-binding sites in mouse cerebral cortex during development and ageing: effects of inhibitory amino acids , 1993, Mechanisms of Ageing and Development.

[19]  C. Dorado-Martínez,et al.  Effects of taurine on ozone-induced memory deficits and lipid peroxidation levels in brains of young, mature, and old rats. , 2000, Environmental research.

[20]  B. Vohra,et al.  Improvement of Impaired Memory in Mice by Taurine , 2000, Neural plasticity.

[21]  P. Rogers,et al.  Effects of low doses of caffeine on cognitive performance, mood and thirst in low and higher caffeine consumers , 2000, Psychopharmacology.

[22]  W. Lovallo,et al.  Effects of caffeine on pressor regulation during rest and exercise in men at risk for hypertension. , 1991, American heart journal.