Roger W Simmons

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Postural stability was measured in 50 patients classified into two diabetic groups: insulin-dependent diabetes mellitus (IDDM: n = 27), and diabetic patients with bilateral cutaneous sensory deficit in the foot (CD: n = 23). All patients were matched to 50 non-diabetic controls on age, weight and gender variables. The integrity of cutaneous sensory(More)
BACKGROUND The present study investigated central and peripheral processing speed using simple reaction time (SRT) and choice reaction time (CRT) tasks in children who were exposed to alcohol in utero compared with control subjects. Each RT interval was fractionated into premotor and motor components to assess the central processing of stimulus information(More)
Trained ballet dancers and nondancer controls completed six balance tests using computerized dynamic posturography. The tests facilitated assessment of the type of sensory organization used to maintain postural control under conditions ranging from quiet standing to a situation in which visual and/or somatosensory information was systematically removed or(More)
BACKGROUND Production of isometric (i.e., constant) force is an essential component of performing everyday functional tasks, yet no studies have investigated how this type of force is regulated in children with confirmed histories of heavy prenatal alcohol exposure. METHODS Children 7 to 17 years old with heavy prenatal alcohol exposure (n = 25) and(More)
Subtle changes in fine motor control have been observed in individuals who carry the Huntington's disease (HD) mutation but have not yet manifested symptoms, referred to as premanifest HD (preHD). However, few studies have examined gross motor impairments in this population. This study sought to examine the role of sensory involvement in maintaining(More)
30 volunteer subjects were required to use either a counting encoding strategy or an imagery encoding strategy to facilitate recall of information from short-term storage. Subjects were also required to use two reproducation cues in combination with two encoding strategies. Analysis indicated no differences between the accuracy at recall of subjects using(More)
The study investigated how children with heavy prenatal alcohol exposure regulate movement speed and accuracy during goal-directed movements. 16 children ages 7 to 17 years with confirmed histories of heavy in utero alcohol exposure, and 21 nonalcohol-exposed control children completed a series of reciprocal tapping movements between two spatial targets. 5(More)
Previous work has reported timing delays in motor response selection in children with prenatal exposure to alcohol when the information load involved responding to two stimulus choices. The present study examined whether the delay in response selection extends to conditions in which the information load is increased to four and eight stimulus choices.(More)
BACKGROUND The study examined whether prenatal alcohol exposure is associated with increased motor timing variability when the timing response is partitioned into central clock variability, which indexes information processing at the central nervous system (CNS) level and motor delay variability, which reflects timing processes at the level of the(More)