Examining the relationship between adolescent health behaviors, brain health, and academic achievement using fNIRS

Background: Several adolescent health behaviors have been hypothesized to improve academic performance via their beneficial impact on cognitive control and functional aspects of the prefrontal cortex (PFC). Specifically, exercise, restorative sleep, and proper diet are thought to improve PFC function, while substance abuse is thought to reduce it. Few studies have examined the relationships among all of these in the same sample, while quantifying downstream impacts on academic performance. Objective: The primary objective of this study is to examine the association between lifestyle behaviors and academic performance in a sample of adolescents, and to examine the extent to which activity within the PFC and behavioural indices of inhibition may mediate this relationship. Methods: Sixty-seven adolescents underwent two study sessions five days apart. Sleep and physical activity were measured using wrist-mounted accelerometry; eating habits, substance use and academic achievement were measured by self-report. Prefrontal function was quantified by performance on the Multi-Source Interference Task (MSIT), and task-related brain activity via functional near-infrared spectroscopy (fNIRS). Results: Higher levels of accelerometer-assessed physical activity predicted higher MSIT accuracy scores (β= .321, ρ= 0.019) as well as greater task-related increases in activation within the right dlPFC (β=.008, SE= .004, ρ =.0322). Frequency of fast-food consumption and substance use were both negatively associated with MSIT accuracy scores (β= -.307, ρ= .023) and Math grades (𝛽= -3.702, 𝑆𝐸= 1.563, ρ= .022) respectively. However, these effects were not mediated by indicators of PFC function. Conclusion: Physical activity and eating behaviors predicted better interference task performance in adolescents, with the former mediated by greater task-related increases in right dlPFC activation. Substance use predicted worse Math grades, however, no other reliable effects of health behaviors on academic outcomes were evident.

Optimizing Adolescent Health Behavior Programs

This article summarizes the key messages and recommendations from the recent National Academies report, Promoting Positive Adolescent Health Behaviors and Outcomes: Thriving in the 21st Century. The first section outlines important definitions and frameworks that guided the committee’s process. Next, the article describes the results of the committee’s systematic review, which aimed to identify the core components of programs and interventions that are effective across a variety of adolescent health behaviors and outcomes. The final section of this article presents a subset of the committee’s recommendations and promising approaches that can be useful to the diverse readership of this journal.