Neuropsychological aspects of cognitive impairments associated with body imbalance

To investigate the possibility that the grade of cognitive impairments modifies the property of body balance, 118 elderly subjects were first classified into three groups, i.e. age-dependent grade A, partially impaired grade B+D and fully disturbed grade C. Procedures for graphic representation of these grades with the use of scores obtained from Mini-Mental State Examination and Japanese Kana-Hiroi Test had been reported elsewhere. Body balance was expressed by the length of body sway and also by the power of low, medium and high frequency spectrum composing of the sway. Posturographic records of the body sway obtained during eyes open and closed both increased in length as the grade decreased from A, to B+D, and C. Associated with these changes, a decrease in the power of low frequency component and an increase in the medium frequency was seen clearly in subjects with grade A.