Citation

Song J, Stough C. Pers. Individ. Dif. 2000; 29(6): 1179-1190.

Copyright

(Copyright © 2000, Elsevier Publishing)

DOI

10.1016/S0191-8869(00)00002-7

PMID

unavailable

Abstract

Morningness-Eveningness refers to individual differences in circadian phase position of spontaneous sleep-wake rhythms and to subject alertness. There is some evidence indicating that performance on cognitive tasks may be influenced by Morningness-Eveningness and time-of-day. Given the potential importance of such a finding for the assessment of cognitive ability we conducted a study assessing the relationship between Morningness-Eveningness, time-of-day, and performance on the Multidimensional Aptitude Battery IQ (MAB-IQ) and Inspection Time (IT) task. Twenty male and 50 female participants classified according to their scores on the Morningness-Eveningness dimension (Horne and Ostberg, 1976) were administered the MAB and IT tasks in the morning (0900[no-break space]h) and in the late afternoon (1500[no-break space]h). No significant effect of time of testing, and Morningness-Eveningness was observed except for the Spatial subtest of the MAB. Morning Type-participants performed significantly worse in the morning session in Spatial subtest and better in the late afternoon session and Evening Type-participants performed significantly better in the morning than in the late afternoon session. These results do not support the hypothesis that there is a reliable relationship between Morningness-Eveningness, time-of-day and cognitive ability.