The aim of this study was to investigate differences among information that varied in interference during drawing tasks in adults with DS. Adults with DS and two comparison groups (Mental Age = MA; Chronological Age = CA) drew bimanual circles and lines coordinated with 3 decreasing rate metronomes: visual information in front of the participant (visual interference), visual information under the hands (reduced visual interference), and auditory information (no visual interference). There were no group differences between metronome conditions, although adults with DS maintained a constant rate despite changing metronome rates. For measures of between hand coordination, the MA group was more variable than adults with DS and the CA group and circles were more variable than lines. These results suggest that adults with DS have difficulty following timing information, regardless of type, for repetitive tasks.
Shannon D. Ringenbach, Annica B. Ericsson and James C. Kao
Shannon D. Ringenbach, Romeo Chua, Brian K. V. Maraj, James C. Kao and Daniel J. Weeks
Previous experiments involving discrete unimanual tasks have shown that individuals with Down syndrome (DS) have auditory/verbal-motor deficits. The present study investigated unimanual and bimanual continuous perceptual-motor actions in adults with DS. Ten adults with DS, 10 typical adults, and 10 children drew continuous circles at increasing periods bimanually and unimanually with each hand. Movement was paced by either a visual or an auditory metronome. The results revealed that for circle shape and coordination measures, children and adults were more accurate with the visual metronome, whereas adults with DS were more accurate with the auditory metronome. In the unimanual tasks, adults with DS displayed hand asymmetries on spatial measures. In the bimanual task, however, adults with DS adopted an in-phase coordination pattern and stability more similar to adults than children. These results suggest that bimanual coordination in adults with DS is functioning effectively despite hand asymmetries evident in unimanual performance.
Jennifer L. Etnier, Benjamin A. Sibley, Jeremy Pomeroy and James C. Kao
Research suggests that there are differences in response time (RespT) as a function of age but that aerobic fitness might have a facilitatory effect on RespT. This study was designed to examine this relationship while addressing methodological issues from past research. Men from 3 age groups completed speeded tasks, a physical activity questionnaire, and an aerobic-fitness test. Results indicated that age has a negative impact on RespT (specifically premotor time and movement time). The interaction of aerobic fitness by age was also a significant predictor of RespT (specifically movement time) such that aerobic fitness was positively related to speed of performance for older participants. It is concluded that aerobic fitness might serve a preservative function for speeded tasks in older adults.