Attention-Deficit / Hyperactivity Disorder (ADHD) is a complex
neurodevelopmental disorder influenced by both genetic and environmental
factors. Among these, stress—whether prenatal or postnatal—plays a pivotal role
in the brain alterations associated with ADHD. This stress can result from
traumatic experiences, adverse socioeconomic conditions, or exposure to harmful
substances.
This study investigates how stress affects brain structure,
connectivity, and functioning, while examining the mediating mechanisms between
stress and ADHD symptoms, offering new perspectives on this critical
environmental factor.
Can stress explain brain alterations in ADHD?
Out of 25,026 identified articles, 20 studies meeting strict criteria
were selected. These studies leverage brain imaging tools to validate stress
exposures and identify structural and functional brain modifications. The
primary objective is to better understand the impact of stress on brain
development in the context of ADHD.
The findings reveal significant impacts of stress on the brain in
ADHD:
- Childhood
trauma: Alterations in
the ventral striatum, amygdala, and hippocampus, affecting reward and
attention-related networks.
- Institutionalization
and socioeconomic deprivation: Reduced brain volumes, particularly in the prefrontal cortex, and
decreased cortical thickness in regions associated with attention and
impulsivity.
- Prenatal
factors: Exposure to
maternal tobacco or alcohol use leads to abnormalities in brain
connectivity, influencing inhibitory control, with strong associations to
birth weight.
Incorporating stress in ADHD management
This review highlights the critical role of stress in brain
alterations associated with ADHD. These findings also underline the need
for an integrative approach to ADHD management, combining the prevention
and management of environmental risks, personalized care based on environmental
risks and individual specificities, and therapeutic innovation to reduce the
impacts of stress on the brain.
