Katsuo Yamanaka

Deficits in long-term retention of learned motor skills in patients with cortical or subcortical degeneration.

We investigated the acquisition and long-term retention of new skills in patients with cortical (Alzheimers disease, AD) and subcortical (progressive supranuclear palsy, PSP; Parkinsons disease, PD) degeneration. The motor skill task performance of the PD and PSP patients improved with training, but the improvement disappeared within a few months, whereas AD patients retained learned skills for 3-18 months. The results of our experiments show that subcortical dysfunction induces a retention deficit for newly learned motor skills. Our present study suggests that a normal striatum is necessary for the formation of long-lasting motor skills, and that the striatum plays an important role as a motor skill consolidation system.

Effects of cognitive stimulation therapy Japanese version (CST-J) for people with dementia: a single-blind, controlled clinical trial

Objectives: Cognitive stimulation therapy (CST) has shown to have significant benefits in improving the cognitive function and quality of life (QOL) in people with mild-to-moderate dementia in a UK randomized controlled trial (RCT). We developed and examined the Japanese version of group CST (CST-J) in a single-blind, controlled clinical trial. Method: CST-J consisting of 14 sessions was administered to a treatment group (n = 26) twice a week for 7 weeks. The treatment group was compared with a control group (n = 30). Based on single-blindness, cognition was evaluated by a researcher, and QOL and mood were rated by the participants themselves. Additionally, QOL and mood of participants were rated by care workers who were not blind but who observed them most directly in their daily life (important for social validity). Results: A linear mixed model was used for analyses of cognition and QOL. There were significant improvements in cognition [COGNISTAT (Neurobehavioral Cognitive Status Examination) and MMSE (Mini-Mental State Examination)] for the treatment group compared with the control group (p < 0.01). Regarding QOL, the EQ-5D was significant (p = 0.019) and the QoL-AD (Quality of Life - Alzheimers Disease) showed a positive trend (p = 0.06) when rated by care workers, although not when rated by the participants themselves. Using a nonparametrical analysis, there were significant improvements in the face scale for mood when rated by both the participants (p < 0.01) and the care workers (p = 0.017). Conclusion: The CST-J shows promising improvements in cognition, mood, and aspects of QOL for people with dementia in Japanese care settings. A large RCT is now needed.

Reliability and validity of the Japanese version of the Alzheimer’s Disease Knowledge Scale

Concerned with the importance of prevailing knowledge about dementia in supporting those with dementia, large-scale educational programs have been implemented in some countries. Although Japan is one of those few countries, the experience from Japanese programs has been rarely shared because of the lack of a standardized measurement for assessing knowledge about dementia. This study aims to develop a Japanese version of the Alzheimer’s Disease Knowledge Scale (JADKS) and to examine its reliability and validity. The JADKS was developed through a translation–back-translation process and was distributed to 837 people including university students, community-dwelling older people, health and welfare professionals, and family caregivers. Using data from the 566 participants who fully completed the questionnaire, test–retest reliability, internal consistency, and concurrent validity were evaluated. The results indicate that the JADKS has acceptable psychometric properties. The JADKS may be useful in assessing knowledge about dementia and could help compare effectiveness of educational programs.