Impact of frequency of internet use on development of brain structures and verbal intelligence: Longitudinal analyses

Abstract

Excessive internet use is shown to be cross sectionally associated with lower cognitive functioning and reduced volume of several brain areas. However, the effects of daily internet use on the development of verbal intelligence and brain structures have not been investigated. Here, we cross sectionally examined the effects of the frequency of internet use on regional gray/white matter volume (rGMV/rWMV) and verbal intelligence as well as their longitudinal changes after 3.0 ± 0.3 (standard deviation) years in a large sample of children recruited from the general population (mean age, 11.2 ± 3.1 years; range, 5.7-18.4 years). Although there were no significant associations in cross sectional analyses, a higher frequency of internet use was found to be associated with decrease of verbal intelligence and smaller increase in rGMV and rWMV of widespread brain areas after a few years in longitudinal analyses. These areas involve areas related to language processing, attention and executive functions, emotion, and reward. In conclusion, frequent internet use is directly or indirectly associated with decrease of verbal intelligence and development to smaller gray matter volume at later stages.

Association of Sedentary Behavior with Brain Structure and Intelligence in Children with Overweight or Obesity: The ActiveBrains Project

“…Conversely, the most recent study from Takeuchi et al revealed that frequency of internet use was not associated with regional gray matter volume in cross-sectional analyses. However, the longitudinal analysis revealed that frequency of internet use was associated with gray matter reductions in widespread clusters, including the bilateral perisylvian areas, the cerebellum and the subcortical regions (e.g., the hippocampus, the amygdala or the basal ganglia; [16]).…”

“…There are only two previous longitudinal studies examining the influence of sedentary behaviors (i.e., watching TV and internet use) on gray matter volume in children [15,16]. One study found that watching more TV was associated with greater gray matter volume in the frontopolar and the medial prefrontal areas in cross-sectional and longitudinal analyses, as well as positive associations in areas of the visual cortex using cross-sectional analyses and positive associations in the hypothalamus/septum and the sensorimotor areas in longitudinal analyses [15].…”

“…Sedentary behavior is one environmental factor that can influence brain structure and function [13]. In healthy children, there are only four studies examining the influence of sedentary behaviors on the brain, with one focused on brain connectivity [14] and the other three on brain structure [12,15,16]. For example, the longitudinal studies from Takeuchi et al in normal-weight children showed that while more time watching TV was associated with greater regional gray matter volume (i.e., in the frontopolar and the medial prefrontal areas, and the hypothalamus/septum and the sensorimotor areas), frequent internet use was associated with a reduction in regional gray matter volume (i.e., the prefrontal areas, the anterior cingulate, the insula, and the temporal and occipital areas) [15,16].…”

The “online brain”: how the Internet may be changing our cognition

“…For instance, the Internet's digital distractions and supernormal capacities for cognitive offloading seem to create a non‐ideal environment for the refinement of higher cognitive functions in critical periods of children and adolescents’ brain development. Indeed, the first longitudinal studies on this topic have found that adverse attentional effects of digital multi‐tasking are particularly pronounced in early adolescence (even compared to older teens), and that higher frequency of Internet use over 3 years in children is linked with decreased verbal intelligence at follow‐up, along with impeded maturation of both grey and white matter regions.…”

Population‐neuroscience study of the Tokyo TEEN Cohort (pn‐TTC): Cohort longitudinal study to explore the neurobiological substrates of adolescent psychological and behavioral development

“…Most of these studies collect information on behavioral and neurocognitive characteristics and/or genetic data from a general population. In Japan, there has been a large‐scale cross‐sectional and longitudinal cohort survey targeting children and adolescents . The targets were set to a relatively broad age range (6–18 years).…”