It has been reported that finger dexterity and cognitive function decline with aging and are related to each other. In our previous study, we developed a training device (iWakka) for adjustability for grasping force. In this study, we developed the iWakka Healthcare System, which provides training for hand dexterity and cognitive function at home using iWakka and allows healthcare professionals to check the daily implementation status. Using this system, a 30-day intervention study was conducted at home with 14 community-dwelling older people to investigate changes in their adjustability for grasping force, cognitive function and verify usefulness of the system. Cognitive function was assessed in executive, attention, and memory functions. The results showed significant improvement in adjustability for grasping force and cognitive function. A process of motor learning over 30 days could be quantified in 11 subjects with approximate curves representing exponential decay. It was found that memory function before the intervention affected the process of motor learning. These results suggest that the iWakka healthcare system may contribute to improving adjustability for grasping force and cognitive function.

A novel diagnostic method has been developed for microvascular lesions using time constants obtained from the peripheral Windkessel model (WK model). Since the time constant of the WK model reflects changes in resistance and vascular elasticity due to a decrease in the internal vessel diameter, an increase in surface roughness of intima, and an increase in blood viscosity, it was proposed to use it as an indicator for vascular evaluation. For noninvasive and easy measurement of the time constant, it is necessary to calculate from the frequency components of the arterial pressure pulse and phalangeal volume pulse. Therefore, it is necessary to establish each pulse wave measurement method and to consider the optimal combination. The fingertip photoplethysmograph was used because it is said to be proportional to the volume pulse of the fingertip. Owing to the difficulty of using the conventional air-conduction method for measuring the arterial pressure pulse, reflection photo and cuff pressure methods were considered. The probability of obtaining time constants and the fluctuation rate were compared across the three methods. The results demonstrated the superiority of the air-conduction method over the other two. The air-conduction method was considered to produce a waveform proportional to the arterial blood pressure pulse wave. The best pulse wave measurement method for measuring peripheral time constants were the air-conduction method for arterial pressure pulse and the transmission photo method for fingertip volume pulse.

The perception of texture is influenced by visual information as well as awareness achieved from foot-sole haptics. Numerous psychophysiological studies have elucidated the effects of visual and haptic information. However, research on the relationship between visual information predicted before a foot sole is placed on the floor and haptic information acquired after stepping on the floor is limited. The existing literature also does not offer any methodology for investigating these effects. This study aimed to build an experimental environment to measure the subjective evaluation (i.e., hardness similarity of visual and haptics stimuli, and comfort) and to examine brain activity by means of fMRI simultaneously when participants were presented with foot-sole haptics stimuli following the projection of visual stimuli. The results revealed a considerable difference in the subjective evaluation of hardness similarity between the visual-haptic similar and dissimilar conditions, which means that we could successfully build the measurement system.

X-ray CT occupies the most essential position among various diagnostic imaging equipment. In this article, the author provides an introductory explanation of CT technology. It is intended to provide some interesting entry points but not an overview of CT as a whole. Regarding the image reconstruction method, the author tried to explain it in a way that facilitates intuitive understanding, in the belief it is more important than formulas. In addition, some interesting topics are picked up that could lead to a better understanding of CT. Some issues that are often misunderstood are also picked up.