In the first study of its kind to explore caffeine’s effects on dynamic visual skills, researchers concluded that caffeine increases alertness and detection accuracy for moving targets. Caffeine also improved participants’ reaction times.
On two separate days, half of the study’s participants ingested a caffeine capsule (4mg/kg) while the other half ingested a placebo capsule. Using a computer-based test designed and validated at the University of Waterloo, each participant’s dynamic visual acuity skills were measured before and 60 minutes after caffeine ingestion.
Researchers found that participants who had ingested the caffeine capsules showed significantly greater accuracy and faster speed when identifying smaller moving stimuli, inferring caffeine positively influences participants’ stimulus processing and decision-making. Eye movement velocity and contrast sensitivity, which are implicated in dynamic visual acuity performance, were also sensitive to caffeine intake.
The study, co-authored by Waterloo’s School of Optometry & Vision Science’s Dalton, and the University of Granada’s Redondo, Raimundo Jiménez, Rubén Molina and Jesús Vera, was recently published in the Psychopharmacology journal.