Chewing affects cognitive processes, but the mechanisms are unknown. We used functional magnetic resonance imaging (fMRI) to examine the relationship between chewing and neuronal activity in the human brain, including the hippocampus and prefrontal cortex. 　Subjects (n=1188, young-adults [mean age : 25.7±5.9 years] 58 men, 73 women; aged adults [mean age 70.3±3.1 years] 421 men, 636 women) performed an encoding test followed by a recall test of 64 photographs (32 photographs used in the encoding test and 32 new photographs). Subjects judged whether they had previously seen each photograph. BOLD (fMRI) signals in the hippocampus and prefrontal cortex were evaluated in some of the young (mean age 26.1±6.3; 15 men, 9 women) and aged (mean age 71.1±3.3; 11 men, 14 women) adults during picture encoding. Subjects chewed gum for 2 min between the encoding and recall tests. 　Memory recall was significantly reduced in aged subjects, but gum chewing increased memory recall by 20%. In young and aged adults, chewing significantly increased fMRI signal intensity in the hippocampus (225%) and prefrontal cortex (240%) and increased the activated brain volume during picture encoding. Chewing enhanced memory recall and activated the hippocampus and prefrontal cortex.

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　The effects of social problem-solving on health and well-being have received considerable attention from Western researchers in recent years. In Japan, however, relatively few attempts have been made to clarify the effects, and even fewer have used a longitudinal design to do that. The purpose of this study has been to examine the effects of social problem-solving on physical and psychological symptoms and psychological stress by using longitudinal data. Additionally, as a secondary goal of this study, revision of the Japanese version of the 17-item social problem-solving scale has been carried out. 　Subjects were 146 college students (mean age 19.9 years old). The subjects participated in two sessions, Time 1 and Time 2, separated by four weeks intervals, and completed the Japanese versions of the social problem-solving scale, the 12-item Somatization, 11-item Depression, and 7-item Anxiety subscales of the Hopkins Symptom Checklist, and the 10-item Perceived Stress Scale in both sessions. 　Hierarchical regression analyses showed that scores on two components of social problem-solving, problem-solving self-efficacy and problem-solving skills, significantly predicted scores for somatization, depression, anxiety, and perceived stress at Time 2, even after controlling for scores for somatization, depression, anxiety, and perceived stress at Time 1, respectively. However, scores for problem-solving skills were not a significant predictor of scores for anxiety at Time 2. Moreover, it was found that the revised version of the social problem-solving scale had good psychometric properties.

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　This study aimed to clarify the relationships between motor ability in preschool children and their favorite play activities, and especially in children who prefer to play tag. The subjects were 167 healthy preschool children aged 4 to 6 (96 boys and 71 girls). The subjects chose three cards picturing their favorite activities, from ten cards depicting ten different activities. The subjects took the following motor ability tests: the 20 meter sprint, standing broad jump, tennis-ball throw, repeated sideways jumps, three ladder tests. 41.7% of boys and 22.5% of girls chose tag. Children who preferred playing tag were superior to the other children in the 20 meter sprint, repeated sideways jumps, slalom jump [ladder test], and open-close jump [ladder test]. When examining the influence of the other activities, significant differences were found in repeated sideways jumps for the soccer choice group and in quick run for the jump-rope choice group. However, the effect size (ES) of repeated sideways jumps was the largest in children who prefer tag. In conclusion, preschool children who prefer tag are superior in agility, including quickly changing movement from right to left and vice-versa. Playing tag, therefore, may foster agility.

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　The purpose of this study was to examine the incidence of volleyball injuries, and to describe the effect of injury incidence, injury type and severity of injury by athletic trainer’s supports. 12 female players from a Japanese volleyball team of the third division in university of Tokai region participated in the study during three seasons from 1 July 2010 to 31 December 2011. Volleyball exposure during training and matches was recorded for each individual player by the athletic trainer on injury reports. 　As a result, we found 76 injuries during 10992 player hours. The total injury incidence was 6.91±6.2 per 1000 hour of play (PH). The incidence of acute injury was 3.28±3.6/1000PH, overuse injury was 3.64±3.3/1000ph. The injury pattern (acute or overuse) differed from each position (p<0.05). The setter had high incidence of acute injury, and the receiver had high incidence of overuse injury. The injury incidence of upper extremities were 0.56±0.6/1000PH, lower extremities were 0.52±0.3/1000PH, trunk/back were 0.33±0.19/1000PH; the hand and finger had the highest injury incidence（1.55/1000PH）. The injury pattern did not change through seasonⅠ〜Ⅲ. The severity of gradeⅠdiffered among gradeⅡand gradeⅢ in

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　Sports facilities for disabled persons in Japan can be categorized into two types: disabled-person-only facilities and inclusive-type facilities. The present study was carried out to identify the factors that affect user satisfaction by assessing how users of two different types of facilities evaluate the quality of the services they receive. To this end, a questionnaire survey was conducted among individual users of a disabled-person-only facility in Osaka and an inclusive-type facility in Kobe. The questionnaire included 39 items related to service quality (items derived from the SERVQUAL model and other items related to the principles of universal design) and an additional item related to user satisfaction. A total of 105 responses were obtained (69 users of the disabled-person-only facility, and 36 users of the inclusive-type facility). The 33 items related to service quality were assessed by performing factor analysis (principal factor analysis and normal varimax rotation) for each facility. By using the factor scores obtained for each facility, multiple regression analysis (stepwise method) was further performed to examine the factors affecting user satisfaction. The analysis revealed the following results: 1) While items under the "tangibles" dimension loaded on a single factor in the inclusive-type facility, they were distributed over three different factors ("people", "physical environment", and "information") in the disabled-person-only facility. 2) The fact that only 4 factors were extracted for the inclusive-type facility, as compared to 7 factors extracted for the disabled-person-only facility, suggests that the inclusive-type facility provided more focused services compared to the disabled-person-only facility. This could be the reason why users showed high levels of satisfaction with instructors. 3) Only the "tangibles" factor was associated with user satisfaction in the inclusive-type facility. 4) The disabled-person-only facility provided a wider range of services compared to the inclusive-type facility. 5) The "empathy" and "information" factors were associated with user satisfaction in the disabled-person-only facility.

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The aim of this study was to evaluate the relationship between reaction times, visual evoked potentials (VEPs), nerve conduction studies (NCSs), and surface electromyography (EMG) in handball players and control subjects. Whole-body reaction time, VEPs, NCSs, and EMG were measured in 15 male (mean, 20.0 ± 1.5 years) handball players and 13 male (mean, 21.3 ± 1.9 years) healthy participants. VEPs were recorded for both eyes separately and together, and the latency of wave P100 was used for evaluation. The activities of the tibialis anterior (TA) and gastrocnemius were measured during whole body reaction time examination, and the root mean square (RMS) activity for each trial was calculated. The players group had faster reaction times than did the control group (0.328±0.043 s vs. 0.441±0.067 s, P < 0.001). The RMS in the TA in the players group was significantly higher than that in the control group (0.137±0.079 and 0.084±0.036, P < 0.05). Multiple regression analysis revealed that P100 and TA activity were significantly associated with reaction time. The results suggest that both P100 and TA activity are independent factors related to reaction time.

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　The Scammon’s growth curve, even during the 80 years since, has been applied to a number of fields. However, one has to wonder if all human characteristics are included in this 4 pattern growth curve classification. Till now, the Scammon’s growth curve has yet to be subjected to scientific verification. That has not been measured, plotted and graphed to make objective distinction possible. In other words, a method to objectively evaluate similarity and dissimilarity in a growth curve has yet to be established. In this study, this assessment was verified by applying a cross-correlation function in analyzing changes from collapsing one of the curves to examine their similarity. Because of that, cross correlation function can then be applied to the quantified curve by Wavelet Interpolation Method. A very high cross-correlation coefficient was shown in the monozygotic twins, and strong similarity was seen. The cross-correlation coefficients differed between the four patterns of the Scammon growth curves. Pattern discrimination was shown to be possible, but unexpectedly, similarity of the testes and liver was shown. What can be newly proposed, therefore, is that growth curve types can be classified as neural, lymphoid, and general body types, with the genital type included in the general body type. The genital type, visceral type, and morphological type are included within the general body type.

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