Development of attentional processes in ADHD and normal children

Area of Science:

• Neuroscience
• Developmental Psychology
• Child Psychiatry

Background:

• Attention Deficit Hyperactivity Disorder (ADHD) is a developmental disorder impacting attentional processes.
• Key deficits in ADHD include impaired response inhibition, error monitoring, and attentional disengagement.
• Understanding the developmental trajectories of these functions is crucial for ADHD research.

Purpose of the Study:

• To examine and compare the developmental trajectories of attentional processes in children with ADHD and typically developing children.
• To investigate age-related changes in executive functions such as response inhibition, error monitoring, and attentional control.
• To determine if cognitive control deficits in ADHD children accumulate with age.

Main Methods:

• A study involving 240 children aged 6-9 years (120 with ADHD, 120 controls).
• Utilized four tasks: Stop-Signal, attentional disengagement, attention network, and choice delay task.
• Analyzed performance metrics including reaction times, switch costs, conflict effects, and delay aversion.

Main Results:

• Children with ADHD exhibited higher stop-signal reaction times, switch costs, conflict effects, and short delay reward choices.
• ADHD group showed less post-error slowing and reduced endogenous orienting effects compared to controls.
• While typically developing children showed developmental improvements in control functions, ADHD children did not exhibit significant age-related changes in most functions.

Conclusions:

• Cognitive control deficits in ADHD appear to be stable and may accumulate with age during childhood.
• The findings support the view of ADHD as a disorder characterized by persistent deficits in executive control functions.
• Results have theoretical implications for executive control theories and understanding the pathology of ADHD.