ABSTRACT
[Purpose] The study investigated the impact of distinct forearm positions on scapular movement and trunk rotation angles. [Participants and Methods] We enrolled 23 healthy young males. Measurements of trunk rotation and relative scapular segment angles were acquired under three conditions employing three-dimensional motion analysis, each executed in a seated posture: (1) both forearms in a neutral position, (2) the forearm on the rotational side adopted supination while the opposite forearm utilized pronation, and (3) the forearm on the rotational side employed pronation while the opposite forearm assumed supination. [Results] The scapular angles in all three scenarios reflected downward rotation, posterior tilt, and external rotation of the rotational-side scapula. Conversely, the contralateral scapula exhibited upward rotation, anterior tilt, and internal rotation. Although the scapular and trunk rotation angles corresponded with the three forearm positions, all three were significantly different and were significantly increased when the rotational-side forearm was in supination (opposite side pronation) and decreased when the rotational-side forearm was in pronation (opposite side supination). [Conclusion] During trunk rotation, regular scapular movements were observed, which varied depending on forearm position and influenced the range of trunk rotation.
ABSTRACT
BACKGROUND/AIMS: Previous studies using near-infrared spectroscopy (NIRS) have reported increases in both oxygenated hemoglobin (oxyHb) and deoxygenated hemoglobin (deoxyHb) during the paper version Trail Making Test (TMT), a neuropsychological test for evaluating cognitive and executive functions. We measured oxyHb and deoxyHb in the prefrontal cortex during the computer version TMT. METHODS: Fifteen healthy students first performed TMT-A and then TMT-B; another 7 students first performed TMT-B and then TMT-A. The mean concentrations of Hb (10 s before TMT, during TMT and 30-40 s after TMT) were determined and analyzed by ANOVA. RESULTS: oxyHb increased while deoxyHb decreased during the TMT. There was a significant order effect on the change in deoxyHb, but not in oxyHb. oxyHb significantly increased in the bilateral prefrontal cortices both in TMT-A and TMT-B. The increase tended to be more prominent in TMT-B than in TMT-A. deoxyHb significantly decreased in the bilateral prefrontal cortices, both in TMT-A and TMT-B. CONCLUSION: The results suggest that blood flow increases in the prefrontal cortex during the performance of TMT, and that the bilateral prefrontal cortices are involved in the performance of the computer version TMT.
