Lower extremity movement preparation and children with attention deficit hyperactivity disorder

Area of Science:

• Neuroscience
• Developmental Psychology
• Kinesiology

Background:

• Attention-Deficit/Hyperactivity Disorder (ADHD) impacts executive functions, including response inhibition and preparation.
• Movement preparation and execution are critical for daily activities and can be affected by cognitive challenges.
• Uncertainty in stimulus occurrence is a known factor influencing reaction times.

Purpose of the Study:

• To investigate how manipulating stimulus uncertainty affects movement preparation and execution in children with and without ADHD.
• To compare the performance of children with ADHD to neurotypical peers under varying levels of response uncertainty.

Main Methods:

• A seated lower extremity choice response time task was administered.
• Participants performed the task with either 10% or 30% catch trials, alongside 27 empirical stimuli.
• Reaction time (movement preparation) and movement time (movement execution) were measured.

Main Results:

• Children with ADHD exhibited significantly slower movement processing than controls under high uncertainty (30% catch trials).
• No significant difference was found between groups under low uncertainty (10% catch trials).
• The findings highlight a specific deficit in movement preparation under uncertainty for children with ADHD.

Conclusions:

• Children with ADHD are disproportionately affected by stimulus uncertainty during the movement preparation phase.
• Increased uncertainty impairs the ability of children with ADHD to prepare for motor responses compared to their peers.
• These results have implications for understanding cognitive-motor deficits in ADHD and designing targeted interventions.