Many students assume that the more caffeine you drink, the better your cognitive performance. Over-consumption of caffeine has many negative effects, so if there are no dose related cognitive benefits to large amounts of caffeine, then college students should limit their intake. This study looked at whether ingesting a medium dose (200 mg) versus a lower dose (100 mg) of caffeine improved short term memory as measured by Flanker and n-back tests, compared to a control group. In addition, we looked at whether larger doses of caffeine produced a difference in neuronal activation during these tests as measured by functional near-infrared spectroscopy (fNIR). There were no differences in cognitive performance observed between the treatment groups, although the 200 mg caffeine group did have significantly more neuronal activation during higher cognitive load tasks. If increased neuronal activation does not correlate to increased performance, it may not reflect an actual benefit of increased caffeine consumption.
Albrecht, Stephan; Morris, Helen; and Vieyra, Michelle
"Dose Dependent Effects of Caffeine on Cognitive Performance and Neuronal Activation,"
Journal of the South Carolina Academy of Science: Vol. 11
, Article 3.
Available at: http://scholarcommons.sc.edu/jscas/vol11/iss2/3