Date of Award

Fall 2002

Document Type

Thesis - Open Access

Degree Name

Master of Science in Human Factors & Systems


Human Factors and Systems

Committee Chair

Steven M. Hall, Ph.D.

Committee Member

Jon French, Ph.D.

Committee Member

Dennis A. Vincenzi, Ph.D.


The purpose of this study was to analyze the performance effects of a low and high dose of caffeine on a Bakan cognitive vigilance task. 69 student volunteers participated in the experiment. Participants were randomly distributed among caffeine dosage levels of 0, 20, and 200 mg. The correct response score, which was chosen as the dependent variable, was collected by the vigilance program, however reaction time and false alarm data was also evaluated. These scores were analyzed over time blocks (first, second, third, or fourth ten minute period of the forty minute task). A 3x4 mixed design ANOVA was performed on each of these data sets to determine if significant mean differences were present. The Stanford Sleepiness Scale was used to evaluate arousal levels before and after the task among caffeine conditions. The NASA TLX was also implemented post-task to evaluate task difficulty between caffeine conditions.