Kouichi Haishi

Postural Sway in Normal and Mentally Retarded Persons

The purpose of this study was: (1) to examine the magnitude of postural sway in persons with mental retardation (PMR) according to clinical types of retardation in comparison with non-handicapped persons, and (2) to investigate the relation between magnitude of sway (MS) and body balance exercises (beam walking and one-foot balance) according to clinical types. The subjects were 134 non-handicapped persons and 45 PMR. The results were as follows: (1) The average MS of autistic persons and other PMR was about the same as that of non-handicapped children aged 4 or 5 years. Among other PMR, however, the MS distribution was relatively large. On the other hand, MS in persons with Down syndrome was generally small, and was similar to that of nonhandicapped children aged 6 years; this small MS appeared to be characteristic of the syndrome. (2) With regard to MS and body balance exercise performance, all subjects in the small magnitude group belonged to the high-performance group except for the persons with Down syndrome.

RELATIONSHIP BETWEEN AGE AND HEAD MOVEMENT DURING STEPPING IN PLACE BY NONHANDICAPPED CHILDREN AND PERSONS WITH MENTAL RETARDATION

We investigated developmental changes in head movement during stepping in place by nonhandicapped children and clarified the relationship between chronological or mental age and head movement of persons with mental retardation. 39 nonhandicapped children aged 3 to 6 years, 13 adults aged 19 to 22 years, and 10 persons with mental retardation (range of chronological age: 17 to 22 years, range of mental age: 3 to 8 years) participated. The total extent of head movement in the frontal plane during ordinary stepping in place for 20.48 sec. was measured to assess the magnitude of head movement. Changes in the magnitude of head movement of children are noticeable across ages, and the magnitude clearly was smaller at the age of 6 years. For subjects with mental retardation, no relationship has been found between chronological age and the magnitude of head movement but rather between mental age and the magnitude of head movement.

AGE-RELATED CHANGES IN POSTURAL CONTROL AND LOCOMOTION " '' '

Age-related changes in both postural control and locomotion were investigated. Postural control was evaluated by magnitude of body sway for 131 healthy persons aged 21 to 84 years. Locomotion was evaluated by walking velocity for 217 healthy persons aged 21 to 88 years. Analysis showed that both abilities deteriorated for older persons and particularly age-related changes were more remarkable in locomotion.

Characteristics of Postural Control and Locomotion of Patients with Vascular and Alzheimer-Type Dementias

The postural control and locomotion of patients with Alzheimer-type senile dementia (n = 20) or vascular dementia (n = 20) were investigated. Patients with both types of senile dementia, especially patients with vascular dementia, generally showed lower scores than healthy old people (n = 53). Moreover, deterioration of locomotion was more remarkable.

EFFECT OF TONE ON DIRECTIONAL ORIENTATION DURING STEPPING IN PLACE WITH EYES CLOSED

To examine the effect of a tone on directional orientation during stepping in place with eyes closed 10 healthy adults ages 20 to 27 years stepped in place for 120 seconds with eyes closed in 3 conditions: without a tone, with 1000-Hz pure tone, and with white noise. To examine how the subject rotated in stepping, both range and dispersion of the heads angular displacement were measured by a compass sensitive to terrestrial magnetism. Analysis showed that white noise was effective for directional orientation during stepping. Also, in the pure-tone condition, angular displacement of the head was similar to that in the no-tone condition. This result may have been due to the fact that the stationary wave created by the interference wave made sound normalization impossible.