Time of day, Intellectual Performance, and Behavioral Problems in Morning Versus Evening type Adolescents: Is there a Synchrony Effect?

We administered measures of fluid and crystallized intelligence to Morning- and Evening-type adolescents who were tested either during a morning session or an afternoon session, at times chosen to reflect the limits of the average school day schedule. For the fluid intelligence measures, there was a synchrony effect, with better performance at times that matched individuals' preferences. A composite measure of the subtests used (block design, digit span, and vocabulary) computed to a 6 point difference in IQ estimates. We also assessed the behavioral adjustment of these participants and found heightened levels of maladaptive behavior for Evening-type adolescents. Adolescents tested at their nonoptimal times of day and adolescents who are Evening-types appear to be at risk for poor academic performance and Evening-types appear to be at risk for behavioral adjustment problems.     

Age differences in choice satisfaction: a positivity effect in decision making

The authors tested the possibility that older adults show a positivity effect in decision making, by giving younger and older adults the opportunity to choose 1 of 4 products and by examining the participants' satisfaction with their choice. The authors considered whether requiring participants to explicitly evaluate the options before making a choice has an effect on age differences in choice satisfaction. Older adults in the evaluation condition listed more positive and fewer negative attributes than did younger adults and were more satisfied with their decisions than were younger adults. There were no age differences among those who did not evaluate options. This evaluation-dependent elevation of satisfaction among older adults was still present when participants were contacted 2 weeks after the experiment. Age did not influence the accuracy with which participants predicted how their satisfaction would change over time.     

Circadian rhythms in executive function during the transition to adolescence: the effect of synchrony between chronotype and time of day

To explore the influence of circadian rhythms on executive function during early adolescence, we administered a battery of executive function measures (including a Go-Nogo task, the Iowa Gambling Task, a Self-ordered Pointing task, and an Intra/Extradimensional Shift task) to Morning-preference and Evening-preference participants (N = 80) between the ages of 11 and 14 years who were tested in the morning or afternoon. Significant Chronotype × Time of Day interactions (controlling for amount of sleep the previous night) revealed that adolescents tested at their optimal times of day performed better than those tested at their nonoptimal times. Implications for our understanding of physiological arousal, sleep, and executive function during adolescence are discussed.