ADHD in Children
🧠1. Neurobiological Basis
a. Brain Structure and Function
- Prefrontal Cortex Dysfunction: This area controls executive functions like attention, impulse control, and working memory. In children with ADHD, it’s often underactive or has delayed maturation.
- Basal Ganglia and Cerebellum: These areas are also implicated, particularly in motor control and behavior regulation.
- Delayed Cortical Maturation: Brain development is slower in children with ADHD, particularly in the frontal lobes.
b. Neurotransmitter Imbalance
- Dopamine and norepinephrine are the key neurotransmitters involved.
- Children with ADHD may have reduced dopamine activity, affecting motivation, attention, and reward processing.
- Norepinephrine affects alertness and response control.
🧬 2. Genetic Factors
- ADHD has a strong genetic component—heritability is estimated at 70–80%.
- Genes involved in dopamine transport and receptor activity (e.g., DRD4, DAT1) are commonly implicated.
🧪 3. Environmental and Perinatal Factors
- Prenatal exposure to alcohol, tobacco, or drugs.
- Low birth weight, premature birth, and birth complications.
- Lead exposure and early psychosocial adversity (e.g., neglect, trauma) may also increase risk.
🧠4. Functional Impairment
The combination of altered brain function and chemical signaling leads to the core symptoms of ADHD:
- Inattention (e.g., distractibility, poor focus)
- Hyperactivity (e.g., fidgeting, restlessness)
- Impulsivity (e.g., acting without thinking)
These symptoms typically appear before age 12 and impact academic, social, and family functioning.
