Fat and lean tissue accretion in relation to reward motivation in children

Triangulating causality between childhood obesity and neurobehavior: Behavioral genetic and longitudinal evidence

Childhood obesity is a serious health concern that is not yet fully understood. Previous research has linked obesity with neurobehavioral factors such as behavior, cognition, and brain morphology. The causal directions of these relationships remain mostly untested. We filled this gap by using the Adolescent Brain Cognitive Development study cohort comprising 11,875 children aged 9-10. First, correlations between the age- and sex-specific 95th BMI percentile (%BMIp95) and neurobehavioral measures were cross-sectionally analyzed. Effects were then aggregated by neurobehavioral domain for causal analyses. Behavioral genetic Direction of Causation modeling was used to test the direction of each relationship. Findings were validated by longitudinal cross-lagged panel modeling. %BMIp95 correlated with impulsivity, motivation, psychopathology, eating behavior, and cognitive tests (executive functioning, language, memory, perception, working memory). Greater %BMIp95 was also associated with reduced cortical thickness in frontal and temporal brain areas but with increased thickness in parietal and occipital areas. Similar although weaker patterns emerged for cortical surface area and volume. Behavioral genetic modeling suggested causal effects of %BMIp95 on eating behavior (β = 0.26), cognition (β = 0.05), cortical thickness (β = 0.15), and cortical surface area (β = 0.07). Personality/psychopathology (β = 0.09) and eating behavior (β = 0.16) appeared to influence %BMIp95. Longitudinal evidence broadly supported these findings. Results regarding cortical volume were inconsistent. Results supported causal effects of obesity on brain functioning and morphology. The present study highlights the importance of physical health for brain development and may inform interventions aimed at preventing or reducing pediatric obesity. RESEARCH HIGHLIGHTS: A continuous measure related to obesity, %BMIp95, has correlations with various measures of brain functioning and structure Behavioral genetic and longitudinal modeling suggest causal links from personality, psychopathology, and eating behavior to %BMIp95 Results also indicate directional links from %BMIp95 to eating behavior, cognition, cortical thickness, and cortical surface area Obesity may play a role for healthy brain development during childhood.

The essential role of theory in minimizing harm from emerging technologies. Lost in committee? •

A coherent framework for addressing risk arising from new technologies is needed. In proposing a framework of broad application and future focus, where empirical evidence is scarce, reliance on strong theory becomes all the more important. Some technologies are more prone to excessive engagement than others (i.e. more addictive). Some users are also more susceptible to excessive engagement than others. Impulsivity theory emphasises the importance of reinforcement magnitude in determining the risk associated with a new technology, and that an individual's sensitivity to reinforcement (reward drive) and capacity to inhibit previously reinforced behaviour (rash impulsiveness) determines their susceptibility to problematic engagement. Online gaming provides a good example of how such theory can be applied to facilitate intervention efforts and develop policy.

Identifying behavioral phenotypes for childhood obesity

Existing programs which aim to prevent and treat childhood obesity often do not take into account individual variation and the underlying mechanisms that impact child eating behavior. Individual differences in children's appetitive traits have been shown to appear as early as during infancy and become more pronounced as children grow older and become more exposed to the obesogenic food environment. Differences in genetic predispositions interacting with factors in children's early environment account in part for individual differences in appetitive traits. It is very likely that obesogenic eating phenotypes manifest themselves before the onset of childhood obesity. If so, identifying these phenotypes early is expected to move primary prevention strategies in a new direction and holds great potential to significantly enhance our ability to prevent childhood obesity. The aim of this narrative review is to discuss the role of behavioral phenotyping as an innovative approach for the development of more personalized obesity prevention and treatment interventions that are tailored to children's individual predispositions. We describe several examples of appetitive traits which have been linked to overeating and excess weight gain in children and thus may represent modifiable risk factors for future interventions. The review concludes with a comprehensive synthesis of opportunities for future human ingestive behavior research on identifying behavioral phenotypes for childhood obesity.