Responses to the Hasegawa Dementia Scale-Revised and the Mini-Mental State Examination were examined for 49 stroke patients to investigate the psychometric equivalence between the two tests. Pearson product-moment correlation and Spearman rank-order correlation between the two tests were 0.87 and 0.78. Each test's scores significantly correlated with the Full Scale IQs on the Wechsler Adult Intelligence Scale--Revised: 0.61 for Hasegawa's Dementia Scale and 0.69 for the Mini-Mental State Examination. These values indicate that the two tests are judged comparable measures for screening cognitive impairment in stroke patients.

Simple reaction times (RTs) of the left or right hand with or without simultaneous vocalization were examined in 14 righthanded subjects. RTs of the simultaneous tasks were longer than those of the single tasks and slowing of RT was larger on the manual than vocal response, particularly on the right side. The results are interpreted as reflecting a different mode of processing in the left and right hemispheres. reaction time; interference effect; hemispheric differentiation Recent studies reported that the manual performance could be varied with the simultaneous speaking. The performance with speaking was less effective than that without speaking, especially on the right hand (Kinsbourne and Cook 1971;Hicks 1975). This interference would be due to a functional overlap of speaking and motor control in the left hemisphere (Lomas and Kimura 1976). Several manual tasks such as dowel balancing (Kinsbourne and Cook 1971; Lomas and Kimura 1976), finger tapping or button-pressing Ashton 1975, 1978;Bowers et al. 1978) and simple reaction time (RT) (Low and Rebert 1978;Rizzolatti et al. 1979) were examined with concurrent mental or verbal performance to analyse the interference effect. Bilateral simultaneous movements took more time to produce motor effect than the separated movement of either arm alone, but the slowing of RT in the simultaneous movement was not different in the left and the right arm , and the degree of interference was the same in the left and right hand . In the present study, we investigated the simple RT of the left or right hand with simultaneous vocalization, and analysed a possible hemispheric differentiation of the interference effect of vocalization on motor performance. METHODThe experiments were performed on 14 right-handed laboratory staffs, seven male and seven female, aged from 21 to 43 years.In a quiet room the subject was seated comfortably on a chair with eyes closed and the forearms rested on a desk. The subject was first given a warning verbal signal

Reaction times (RTs) of vocalization were examined for 20 normal subjects under two conditions, standing and walking. The RT during walking was not related to the phases of walking cycle. The difference in RTs (ΔRT) was obtained by subtracting RT for standing from that of walking. The correlation coefficient between RT for standing and ΔRT was significant and negative. ΔRTs for subjects with fast RT for standing were positive, whereas those with slow RT were negative. Assuming that the arousal level when standing is different between the faster and slower reactors, the probe-RT during walking would reflect not only the extra-attentional demands of walking but also the shift in arousal.

Using the formulae for prediction of functional status at 4, 8 and 12 weeks after admission in the stroke patient (simplified version of Recovery Evaluating System-3; RES-3) and demographic data at the admission of 128 stroke patients, the estimated scores of four measures, Motor Age Score (MOA), Manual Function Score (MFS), Barthel Index (BI) and Mini-Mental State (MMS), were obtained. Fitness of the formulae was tested in terms of the agreement between the estimated and the measured scores. The results indicated that the differences between the measured and the estimated scores were statistically not significant except BI. The measured scores of BI were 3 to 5 points high compared to the estimated ones. When the confidence limits of the differences were examined at a confidence coefficient of 95%, they were within 5% of the full score for MOA, MFS and MMS, and were within 10% for BI. Accordingly, by setting the allowable limit to 5% of the full score around the means, the fitness of prediction would be more than a probability of 95%. The formulae of simplified version of RES-3 were practically useful.

Reaction times (RTs) to light stimuli which appeared at central and lateral positions were measured in 13 normal subjects and 34 patients with unilateral lesions in the left or the right hemisphere. The normal subjects showed slowing of RTs to both lateral stimuli compared to the central stimulus, the extent of which was equal between the left and right hands. The patients with left hemispheric lesions had slower RTs to the stimulus contralaterally to the lesion than ipsilaterally and centrally. The patients with right hemispheric lesions had slower RTs both to the contralateral and central stimuli than to the ipsilateral. The results are discussed in relation to functional differentiation of the left and right hemispheres for visual processing. reaction time; visual perception; left-right differentiation it is well known that each hemisphere represents or controls principally the contralateral side of the body. However, recent neuropsychological studies have revealed that the right hemisphere is of primary importance for complex visuospatial functions and for more fundamental perceptual processes (Kimura and lJurnford 1974).Carmon and Benton (1969) observed that patients with right hemispheric lesions showed an impairment in the discrimination of tactile stimuli on both hands, while patients with left hemispheric lesions showed an impairment only on the right hand. According to Hosokawa et al. (1981) who examined the tone-gap delectability in normal subjects and patients with unilateral subcortical lesions, the right subcortical lesions resulted in loss of the efficiency of binaural system. Studying the postural dependence of reaction time (RT) in patients with ventrolateral thalamotomy, Nakamura et al. (1979) reported that the right hemisphere including subcortical structures had bilateral control on the proprioceptive input. These studies suggest that the right hemisphere receives information from sensory receptors in both sides of the body, whereas the left only from the contralateral side. Then, for visual perceptions, it is likely that the right hemisphere covers wider visual fields than the left hemisphere. Therefore, it would be expected that RT performance to