Mechanisms that underlie coordination in children with developmental coordination disorder.

The authors examined potential mechanisms underlying motor coordination in children with developmental coordination disorder (DCD). Because children with DCD experience difficulty processing visual, auditory, and vibrotactile information, the authors explored patterns of choice reaction time (RT) in young (6-7 years) and older (9-10 years) children with and without DCD by using a compatibility-incompatibility paradigm and different sensory modalities. Young children responded more slowly than older children to visual, auditory, and vibrotactile stimuli. Children with DCD took longer than typical children to process visual and vibrotactile stimuli under more complex stimulus-response mappings. Young children with DCD responded more slowly than typical children to visual and vibrotactile information under incompatible conditions. Children with DCD responded faster than unaffected children to auditory stimuli. The results suggest that there is a developmental nature in the processing of visual and auditory input and imply that the vibrotactile sensory modality may be key to the motor coordination difficulties of children with DCD.

Cardiovascular and electroencephalographic responses to purposeful versus nonpurposeful activities in children.

To discern effects of purposefulness on cardiovascular and neural responses, heart rate and electroencephalographic recordings were taken in 31 children performing purposeful and nonpurposeful activities of equal duration and cardiopulmonary workload. Heart rate increased from resting levels during both purposeful (p = .001) and nonpurposeful (p = .01) activities, but the level of increase was the same for both (p = .30). Similarities in heart rate during purposeful and nonpurposeful activities suggest that purposefulness might not influence heart rate response in children. Encephalographic recordings did not show a higher beta-wave activity quotient during purposeful activity (p = .33).

Cardiovascular and Electroencephalographic Response to Purposeful vs. Nonpurposeful Activity in Adults (†).

eEffects of purposefulness on heart rate, blood pressure, and electroencephalographic recordings were examined in 32 adults performing purposeful and nonpurposeful activities of equal cardiopulmonary workload. Blood pressure increased from resting during purposeful and nonpurposeful activity (all p < .02); the level of increase was similar for purposeful and nonpurposeful activity [systolic (p = .44); diastolic (p = .25)]. No significant differences in heart rate (p = .42) or electroencephalographic beta wave activity (p = .39) were noted between purposeful and nonpurposeful activities. These findings suggest that the degree of purposefulness of the activity did not influence the cardiovascular response.