Fractioned reflex and reaction time in children with developmental coordination disorder

Area of Science:

• Neuroscience
• Developmental Psychology
• Motor Control

Background:

• Developmental Coordination Disorder (DCD) affects motor skills and may impact cognitive processing.
• Previous research indicates motor difficulties in DCD, but reflexive and volitional response processing remains less understood.

Purpose of the Study:

• To compare the processing of reflexive (patellar tendon reflex - PTR) and volitional (simple visual reaction time - RT) responses in children with DCD and normal coordination (NC).
• To investigate the effects of age and coordination level on different temporal components of these responses.

Main Methods:

• Forty children were divided into four groups: 6-year-old DCD (6DCD), 6-year-old NC (6NC), 9-year-old DCD (9DCD), and 9-year-old NC (9NC).
• Patellar tendon reflex (PTR) and simple visual reaction time (RT) were measured and fractionated into components like reflex latency, premotor time, and motor time.
• Analysis of Variance (ANOVA) was used to compare groups based on coordination and age.

Main Results:

• PTR components were largely unaffected by coordination level, but a significant interaction showed increased motor time in 6DCD compared to 6NC.
• Simple visual reaction time (RT), premotor time, and motor time were all significantly increased in children with DCD compared to NC peers.
• The increased motor time in DCD children for RT was a novel finding.

Conclusions:

• Children with DCD exhibit distinct temporal processing deficits in both reflexive and volitional motor responses compared to typically developing peers.
• These findings highlight differences in neural processing underlying motor control in DCD.
• The study suggests that motor and cognitive processing are intertwined in DCD, impacting response execution.