Citation

Laird DA. J. Exp. Psychol. 1925; 8(1): 50-63.

Copyright

(Copyright © 1925, American Psychological Association)

DOI

10.1037/h0067673

PMID

unavailable

Abstract

The alleged rhythmical fluctuations of physiological and psychological processes--seasonal, daily, and hourly--has occupied the attention of some workers in these fields for many years. Altogether a great deal of experimental work has been done in investigations that, when critically considered, are far from decisive. It would be of much practical and theoretical value to know in detail about these fluctuations in performance that appear to be conditioned--remotely, perhaps--by chronological and meteorological factors. Tests of speed of reading for understanding, grasping of important points from selections read, retention of important items from reading after a few minutes and for forty minutes, were given to 112 college students according to a schedule that made it possible to compare their performance on these tests either for the days of the week or for the hours of the day. It has been found that the performance was at its peak on Wednesday, that it gradually approached the high point on this day and abruptly declined on the day following to a very low level. In general all of the individual tests followed this curve of rise and fall. From 8 A.M. until the period from 4 to 5 P.M. there was found a steady decline at the hours studied. From 8 P.M. until 10 P.M. there is a rise, which, however, scarcely comes up to the average of the day. From 10 to 11 P.M. there is a loss. These conclusions apply, not necessarily to every individual student, but represent accurately the average performance of a large group, or the 'typical student.' It may perhaps be that there are individual exceptions to these findings as the result of habits of study and work. It is doubtful if there are variations as a result of one student being intrinsically and apart from habits of work different from others. (PsycINFO Database Record (c) 2012 APA, all rights reserved)