The Influences of Day of the Week on Cognitive Performance

Aim: The aim of the present study is to document and explain changes in cognitive performance that occur from day to day.

Study Design: This is a between-subjects design.

Place and Duration of Study: The University of Texas at San Antonio, Department of Psychology, 2006-2009.

Methodology: Two hundred and thirty fluent English speaking students from the Introductory Psychology classes from the University of Texas at San Antonio participated in this study for course credit. Each participant completed the component processes task [1], a measure of multiple cognitive processes, on either Monday, Tuesday, Wednesday, or Thursday. Data for Fridays were not collected because there was a lack of availability of participants and research assistants at the necessary times.

Results: The results revealed that performance for some cognitive processes vary as a function of the day of the week. Whereas cognitive processes used for learning and integrating new information were better later in the week, cognitive processes used for accessing what one knows remained unchanged.

Specifically day of the week influenced text memory such that performance was better on Thursday than on Monday (i.e., 83.1 versus 75.1), F (1, 88) = 6.22, P = .02. Further, day of the week also influenced the two composite measures text-based processes and learning processes such that performance for both of these measures was also better on Thursday than on Monday, minimum F (1, 88) = 4.87, P = .03. However, although performance on text inferencing and combined knowledge integration had a tendency to be better on Thursday than Monday, this tendency was not significant, maximum F (1, 88) = 3.27, P = .07. Further, performance did not differ on Monday versus Thursday for low-knowledge access, high-knowledge access, and the composite measure for knowledge access, maximum F < 1.0.

Conclusion: Taken as a whole, these results suggest that both teachers and students should consider the day of the week when trying to maximize cognitive performance.