Students with mild mental retardation (MMR) often demonstrate reluctance, confusion, or performance deterioration when required to perform tasks that require looking, reaching, or stepping across the body’s midline. Sensory integration theorists contend that midline crossing is a predictor of bilateral integration. However, in factor analysis studies, very little variance is accounted for by midline crossing data. The present study viewed midline crossing as a function of information processing and utilized a temporal assessment process rather than the usual spatial assessment process. Results indicated that subjects classified as MMR experienced slower choice reaction time (CRT) and movement time (MT) for stimuli placed across the body’s midline. However, higher functioning subjects with MMR performed equally well on CRT for ipsilateral and crosslateral tasks. The data provide evidence for a developmental hypothesis as an explanation for midline crossing problems.

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The purpose of this study was to describe the developmental stepping movements of 5 infants with Down syndrome who participated in a pediatric strength intervention. Pretest and posttest data were collected with the Hawaii Early Learning Profile Strands, Battelle Developmental Inventory, and specially designed gait analysis. An 8-week individualized pediatric strength intervention was implemented according to theoretical principles of progressive interactive facilitation (Cowden, in press). Posttest data and the Snyder-McLean (1987) intervention developmental quotient suggested an increase in the subjects’ rates of motor development during intervention as compared to their lifetime rates prior to intervention. One subject showed increased rate and distance, 2 subjects acquired independent upright locomotion, and 1 subject established independent sitting movements and creeping patterns. One subject was unable to complete the study.

Midline crossing refers to behavior that results in reaching, stepping, or looking, across the body's midline. Several studies have indicated that infants, young children, and individuals with disability make more errors on midline-crossing tasks than on similar tasks placed at the ipsilateral side. Until recently, assessment of midline crossing has used a spatial protocol and has been criticized for not having a temporal component. The purpose of this study was to assess midline crossing by 9 4-yr.-old children within an information processing context. Analysis indicated that contralateral tasks required more processing time than similar tasks placed ipsilaterally.

This study determined the effects of achromatic and multichromatic targets and darts on throwing. Subjects were 56 college men assigned to one of four dart-and-target throwing conditions as follows: white target--white darts, white target--multi-colored darts, multi-colored target--white darts, and multi-colored target--multi-colored darts. Subjects threw from 20 ft. using an overhand throwing pattern. The main effect of target color and the interaction of target color and dart color were significant. The results indicated that white backgrounds are superior to colored backgrounds. Also, the interactions of colored darts against a white background produced the best combination for performance. In target tasks which depend upon response-produced feedback, color of figures and background interact apparently to affect motor performance.