Acute effects of theanine, caffeine and theanine-caffeine combination on attention

Objective: l-theanine is a constituent of tea which is claimed to enhance cognitive functions. We aimed to determine whether theanine and theanine-caffeine combination have acute positive effects on cognitive and neurophysiological measures of attention, compared to caffeine (a positive control) and...

Full description

Saved in:
Bibliographic Details
Published in:Nutritional neuroscience 2017-07, Vol.20 (6), p.369-377
Main Authors: Kahathuduwa, Chanaka N., Dassanayake, Tharaka L., Amarakoon, A. M. Tissa, Weerasinghe, Vajira S.
Format: Article
Language:English
Subjects:
Adult
Attention
Caffeine
Caffeine - administration & dosage
Coffee
Cognition
Cognitive effects
Cross-Over Studies
Dietary Supplements
Event-related potentials
Evoked Potentials, Motor
Evoked Potentials, Visual
Glutamates - administration & dosage
Humans
Male
Motor Activity
Nootropic Agents - administration & dosage
P300
Pattern Recognition, Visual
Performance-Enhancing Substances - administration & dosage
Reaction Time
Sri Lanka
Students
Tea
Theanine
Universities
Young Adult
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Objective: l-theanine is a constituent of tea which is claimed to enhance cognitive functions. We aimed to determine whether theanine and theanine-caffeine combination have acute positive effects on cognitive and neurophysiological measures of attention, compared to caffeine (a positive control) and a placebo in healthy individuals. Design: In a placebo-controlled, five-way crossover trial in 20 healthy male volunteers, we compared the effects of l-theanine (200 mg), caffeine (160 mg), their combination, black tea (one cup) and a placebo (distilled water) on cognitive (simple [SVRT] and recognition visual reaction time [RVRT]) and neurophysiological (event-related potentials [ERPs]) measures of attention. We also recorded visual (VEPs) and motor evoked potentials (MEPs) to examine any effects of treatments on peripheral visual and motor conduction, respectively. Results: Mean RVRT was significantly improved by theanine (P = 0.019), caffeine (P = 0.043), and theanine-caffeine combination (P = 0.001), but not by tea (P = 0.429) or placebo (P = 0.822). VEP or MEP latencies or SVRT did not show significant inter-treatment differences. Theanine (P = 0.001) and caffeine (P = 0.001) elicited significantly larger mean peak-to-peak N2-P300 ERP amplitudes than the placebo, whereas theanine-caffeine combination elicited a significantly larger mean N2-P300 amplitude than placebo (P 
ISSN:1028-415X
1476-8305
DOI:10.1080/1028415X.2016.1144845