The purpose of this study was to compare the features of joint angle and muscle activity of standing up movement from a chair in PD (Parkinson's disease) patients and healthy individuals, for design of the chairs assisting standing up movement of PD patients. Twelve PD patients and 12 healthy individuals participated in this study. We measured the joint angle and muscle activity (electromyogram) in the lower limbs, and the ground reaction force during standing up movement from an armchair. In terms of the timing of change of the joint angle and the working joint angle, no significant difference was found between the PD patients and healthy individuals. However, the timing of PD patients in the movement from the start point of the rectus femoris to the start point of the tibialis anterior was significantly shorter than that of the healthy individuals. These results show that PD patients have specific features of muscle activities in standing up movement from a chair.

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This study investigates the process of reading the Thai language with eye tracking. The results found that the number and duration of fixations increased according to the difficulty of sentences. The fixation distributions for reading languages such as English and Japanese are longer at the beginning of words where morphological attributes are positioned. On the contrary, Thai readers in this experiment tended to look at the end of the words which was assumed to be because the final consonants (Tuasakot) play an important role when reading Thai. The final consonants (Tuasakot) are indistinguishable from other consonants based on their morphological characteristics. Thus, it was assumed that higher cognitive processing is required for Thai reading. Additionally, our experiments on word cognition processing found the evidence of the word superiority effect. Therefore, it has become clearer that final consonants act as a trigger to differentiate words and facilitate the reading process. In conclusion, higher cognitive processing is required to distinguish words and processing final consonants correctly, and Tuasakot are required for reading Thai.

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Effective grasping arrangements were tested using various arrangements of graspable objects and hands positioned to perform the grasping action. Forty-two participants were simultaneously shown pictures of objects (tools and tableware, such as a cup or pliers) and one grasping hand in various arrangements and asked to rate whether the object and the hand were arranged in such a way that the object would be easy to grip. Results show that the alignment effect was not observed for some arrangements. In addition, when the object and hand were congruent with the orientation of the participant's body, the object was not always considered to be easily graspable. However, some participants felt that arrangements were easily graspable even when the arrangement was not congruent with the orientation of their bodies. The results suggest that an effective grasping arrangement is affected by the visual characteristics of the shape of the object and by the arrangement of both the object and the body, but that the object's alignment, congruency, and orientation with the body are not always required for effective grasping.

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The objective of this study was to investigate an optimum crutch handle bar diameter that is easy for grasping and leads less efforts by hands, wrists and fingers. Sixteen healthy young adult males walked with a right-leg-support, swing-through gait motion using one pair of standard axillary crutches with six handles having different diameters (25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, measured lengthwise from the center). During the gait, surface electromyography from flexor digitorum superficialis (FDS) and extensor digitorum communis, wrist posture (flexion and extension), the distribution of externally applied pressure on the palm and subjective evaluation were measured. The results showed that the thicker handle conditions (40 mm, 45 mm and 50 mm) led to a lower pressure on the palm. In addition, wrist posture was more extended in thicker handle conditions than in thinner ones. On the other hand, thinner handle conditions (25 mm and 30 mm) resulted in higher FDS activity. The subjective evaluation showed the 35 mm handle diameter was most suitable for grasping. In conclusion, the handle diameter 35～40mm, which is about 19～22％of hand length, is regarded as the optimum handle size of axillary crutches for young adult males.

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