Association of chronotype and social jetlag with human non-verbal intelligence

Abstract

The aim of this study was to evaluate the effects of chronotype and social jetlag (SJL) on intelligence. Subjects were aged 14-25 years (n = 1008). A significant effect of intelligence on academic performance, as measured by the Raven's Standard Progressive Matrices test, was found (F = 11.75, P < 0.0001, η = 0.03). When SJL was less than 2 hours, the intelligence of people with late chronotype was found to be higher than that of subjects with early and intermediate chronotypes (F = 3.12, P < 0.05, η = 0.02). A negative effect of SJL on the results of intelligence testing was noted only in subjects with late chronotype (F = 2.61, P < 0.05, η = 0.02). Our data suggest that people with late chronotype have a higher level of intelligence, but these advantages disappear when SJL ≥2 hours.

Association between Chronotype and Nutritional, Clinical and Sociobehavioral Characteristics of Adults Assisted by a Public Health Care System in Brazil

“…Most of the morning CT participants showed fewer years of education in our study. The relationship between CT, intelligence and academic performance has been described in a controversial way in the literature [ 51 , 54 , 55 ]. Evening individuals are positively related to cognitive ability, yet negatively related to indicators of academic achievement [ 51 ] due to social jetlag (desynchronosis caused by misalignment between social and biological clocks) [ 6 , 55 ].…”

“…The relationship between CT, intelligence and academic performance has been described in a controversial way in the literature [ 51 , 54 , 55 ]. Evening individuals are positively related to cognitive ability, yet negatively related to indicators of academic achievement [ 51 ] due to social jetlag (desynchronosis caused by misalignment between social and biological clocks) [ 6 , 55 ]. Panev et al found that evening individuals present a higher level of intelligence, but these advantages disappear when social jetlag is greater than 2 h [ 55 ].…”

Morningness–eveningness is not associated with academic performance in the afternoon school shift: Preliminary findings

“…Furthermore, SJL has been related to depressive symptoms (Levandovski et al ., ), seasonality (Polugrudov et al ., ), physical aggression (Randler & Vollmer, ), and lower academic performance (Díaz‐Morales & Escribano, ), with the latter study indicating that SJL may also impact on basic cognitive abilities. Recently, SJL was also found to be negatively related to nonverbal intelligence (Panev et al ., ).…”

Short Sleep Duration and Extremely Delayed Chronotypes in Uruguayan Youth: The Role of School Start Times and Social Constraints

“…This misalignment between students’ chronotypes and school time was also associated with lower grades and performance ratings in 2 meta-analyses (Preckel et al, 2011; Tonetti et al, 2015). Social jetlag (SJL), a behavioral index of circadian misalignment (Wittmann et al, 2006), has been related to adolescent school performance (Díaz-Morales and Escribano Barreno, 2015; Haraszti et al, 2014) and cognition (Panev et al, 2017). Based on this evidence, there have been several attempts of delaying school start times and making them more flexible, some of which have resulted in reported improvements in sleep (increased sleep duration and reduced sleepiness), school attendance, performance, mood, and negative behaviors (American Academy of Pediatrics, Committee on Adolescence, and Council on School Health, 2014; American Medical Association, 2016; Bowers and Moyer, 2017; Dunster et al, 2018; Fischer et al, 2008; Kelley et al, 2015; Louzada and Pereira, 2019; Minges and Redeker, 2016; Watson et al, 2017; Wheaton et al, 2016; Winnebeck et al, 2019).…”