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Reaction Time

Reaction time refers to one's reflexes and the speed of which a task can be done, and is a cognitive parameter that is of interest to athletes or persons in need of more rapid coordination.

Research analysis led by Kamal Patel.
All content reviewed by the Examine.com Team. Published:
Last Updated:

Human Effect Matrix

The Human Effect Matrix looks at human studies (it excludes animal and in vitro studies) to tell you what supplements affect reaction time
Grade Level of Evidence
Robust research conducted with repeated double-blind clinical trials
Multiple studies where at least two are double-blind and placebo controlled
Single double-blind study or multiple cohort studies
Uncontrolled or observational studies only
Level of Evidence
? The amount of high quality evidence. The more evidence, the more we can trust the results.
Outcome Magnitude of effect
? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
Consistency of research results
? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.
grade-b Caffeine Minor Moderate See all 5 studies
Although the overall effect is unreliable and context dependent, caffeine appears to improve reaction time (possibly at the cost of accuracy)
grade-b Modafinil Minor High See all 3 studies
An improvement in reaction time (decrease) is noted in both healthy and normal persons as well as those undergoing either drug addiction or sleep deprivation. This may be related to the alertness promoting effects of the compound.
grade-c Kava Notable - See study
The one study to measure reaction time noted an astounding decreased (approximately 40% reduction), which needs to be replicated
grade-c Alanylglutamine  
grade-c Branched Chain Amino Acids  
grade-c Centella asiatica  
grade-c Fish Oil  
grade-c Ginger  
grade-c Ginkgo biloba  
grade-c Marijuana  
grade-c Nicotine  
grade-c Panax ginseng  
grade-c Policosanol  
grade-c Vinpocetine  
grade-c Zinc  
grade-c Choline  
grade-c D-Serine  
grade-c PRL-8-53  
grade-c Phosphatidylserine  
grade-c Rhodiola Rosea  
grade-c Sceletium tortuosum  
grade-c Theanine  

All comparative evidence is now gathered in our ​A-to-Z Supplement Reference.

The evidence for each separate supplement is still freely available ​here.