# Resting-State Sensory-Motor Connectivity between Hand and Mouth as a Neural Marker of Socioeconomic Disadvantage, Psychosocial Stress, Cognitive Difficulties, Impulsivity, Depression, and Substance Use in Children

## TL;DR

This study finds that brain connectivity between hand and mouth regions in children is linked to socioeconomic disadvantage, stress, and future substance use.

## Contribution

The study identifies resting-state sensory-motor connectivity as a novel neural marker for multiple socio-behavioral and mental health outcomes in children.

## Key findings

- Higher connectivity between sensory-motor mouth and hand regions is associated with lower socioeconomic status and greater trauma exposure.
- Increased connectivity correlates with impulsivity, depression, and future marijuana use.
- Sensory-motor connectivity reflects the impact of early-life adversity on mental health and behavior.

## Abstract

The sensory-motor network is essential for integrating sensory input
with motor function and higher-order cognition. Resting-state functional
connectivity (rsFC) within this network undergoes significant developmental
changes, and disruptions in these connections have been linked to behavioral
and psychiatric outcomes. However, the relationship between sensory-motor
connectivity, early-life adversity, and later health behaviors remains
understudied.

This study examines the associations between rsFC within the
sensory-motor network (mouth and hand regions) and key social,
psychological, and behavioral factors, including baseline and past
socioeconomic status (SES), trauma exposure, family conflict, impulsivity,
major depressive disorder (MDD), and future substance use.

Data were drawn from the Adolescent Brain Cognitive Development
(ABCD) Study, a national sample of U.S. children. Resting-state fMRI data
were used to assess functional connectivity within the sensory-motor
network. Bivariate analyses examined associations between rsFC in the
sensory-motor mouth and hand regions and baseline SES, past SES, childhood
trauma exposure, family conflict, impulsivity, and MDD. Longitudinal
analyses assessed whether baseline rsFC predicted future substance use.

Greater rsFC between the sensory-motor mouth and hand regions was
significantly associated with lower SES, higher trauma exposure, and greater
family conflict. Increased connectivity was also correlated with older age
and more advanced puberty status. Higher rsFC between the sensory-motor
mouth and hand regions was linked to greater impulsivity, lower cognitive
function, an increased likelihood of MDD, and future marijuana use.

These findings suggest that sensory-motor connectivity is sensitive
to socioeconomic and psychosocial stressors, with potential long-term
implications for mental health and substance use risk. The results highlight
the importance of early-life environmental factors in shaping
neurodevelopmental trajectories and emphasize the need for targeted
interventions to mitigate the effects of adversity on brain function and
behavior. Future research should further explore the role of sensory-motor
network alterations in behavioral health outcomes as a function of
environmental stressors.