Subjects were for 40 healthy individuals (25.3 ± 6.8 yrs). Each task was performed for 5-minutes under eye-close lying, eye-close sitting, and eye-open sitting. The measurement sites corresponded to the left and right frontal lobes in accordance with the International 10-20 System. The expression number that represents the components of α and β waves quantified every three seconds was determined for five minutes, and expression time, mean expression number, and rate of change were determined and statistically analyzed. The site where the expression time of α and β waves was five minutes was only the left frontal lobe in all of the subjects in the eye-open sitting. There was a significant difference (P<0.05) in the mean expression number of α and wave in the left and right frontal lobe between subjects in the eye-open sitting and those in the eye-close sitting. There was a significant difference (P<0.001) in the rate of change of α and β wave in the left frontal lobe between subjects in the eye-close lying and those in the eye-open sitting. Consideration, it is important to observe the time of expression of α and β waves when the eyes are not stimulated. The results that agree with physiological change, indicated the possibility of evaluating frontal lobe activity on the basis of the mean expression number and the rate of change of α and β waves.
In the present study, we attempted to clarify the activity pattern of the cerebral cortex that is involved in a coincidence anticipation timing task using a downward moving visual target. The subjects were ten healthy adult males. All the subjects were right-handed. The tasks consisted of a non-coincidence anticipation timing task as the control task and a coincidence anticipation timing task using a downward moving visual target on a computer display. Both tasks were carried out on a computer display placed at approximately 1.3 m from the subject. An electroencephalogram (EEG) was recorded from electrodes placed at 128 sites on the subjects’ scalp. The EEG was divided into the frequency band of the alpha component (8-13 Hz) and the beta component (13-30 Hz) by fast Fourier Transform (FFT) analysis and then analyzed. In addition, the alpha and beta components were each compared for 18 sites, based on the international 10/20 system without Cz between the control task and the coincidence anticipation timing task.
The results showed that the alpha component decreased significantly at F7 and T3 in the coincidence anticipation timing task compared with that of the control task, the beta component increased significantly at C4, T3, and P3, and the beta component significant decreased at Fp1 and Fp2. These results of a comparison between two tasks, suggest that parietal, temporal, motor, premotor, and frontal pole areas are involved with the execution of the coincidence anticipation timing task using a downward moving visual target.
We investigated the effects of neck flexion on reaction time in memory-guided and visually-guided saccades. Twelve healthy subjects performed reaction time tasks for visually-guided and memory-guided saccades in neck resting and neck flexion conditions. Reaction times for memory-guided and visually-guided saccades were significantly shortened for the neck flexion condition compared with the neck resting condition. The reduction in reaction time during neck flexion was significantly larger for memory-guided saccade than for visually-guided saccade. These results cleared that the effect of neck flexion on reaction time was larger in memory-guided saccade, which involves higher nervous function, than in visually-guided saccade.
The present study was to clarify the effect of muscle vibration during simple and multi-joint movements of wrist-elbow in normal humans. In the first experiment, a vibrator was fixed over antagonistic muscles (either TB or ECR) with both elbow and wrist flexion occurring. Likewise, in the second experiment, a vibrator was mounted over either TB or ECR when multi-joint movements occurred. In both experiments, muscle vibration (100 Hz) was started prior to movement initiation and ceased when the movement was terminated. Subjects performed singly or simultaneously elbow and wrist flexion movements in a tracking paradigm using visual feedback of oscilloscope (CRT) including two bar-beams of forearm-angle and target position. Slow movement is to move “three seconds attainment” between the target bars. After those practices, blindfolded subjects performed ten trials. During some movements, angle of joint (wrist, elbow) and EMG (BB, TB, FCU, ECR) were measured in all experimental conditions. The observed results, vibration of the antagonist muscle (ECR or TB) resulted in an undershoot of the simple movement. The multi-joint movement, vibration of the ECR or the TB resulted in an undershoot of elbow flexion movement whereas the wrist flexion movement resulted in end position accurately. The above results seemingly suggest that muscle vibration induced kinesthetic illusion in CNS leading to motor illusion (undershoot) due to motor command of elbow flexion movement. The illusions also activated contralateral motor cortex (M1), primary and secondary somatosensory cortex (S1, 2), dorsal premotor cortex (PMD), cingulate motor area (CMA), and supplementary motor area (SMA).
The purpose of the present study was to characterize the effect of the ratio of heart rate (HR) and breathing rate (BR) (HBR) on oxygen uptake (VO2) during ramp-load leg cycling exercise (RLE) and constant-load leg cycling exercise (CLE) at below ventilation threshold (VT). Seventeen subjects (age: 30.5 ± 2.4 yrs) participated in this study. The subjects were classified into two groups using an index of HBR: increasing HBR group (HBRi) and not-increasing HBR group (HBRn). Cycling was performed at RLE and CLE at 90% VT for 4 min, and at rest for 4 min with five repeated bouts of exercise. During rest and exercise, expired gases, ECG and EMG (vastus lateralis) were measured simultaneously. There was no difference in the rate of VO2 for work load (ΔVO2/ΔWR) between HBRi and HBRn with RLE. The rate of rmsEMG (ΔrmsEMG/ΔWR) was significantly lower in HBRi than in HBRn during RLE (p < 0.0001). The rate of body CO2 stores (ΔCO2 store/ΔWR) was significantly higher in HBRi than in HBRn with RLE (p < 0.0001). In CLE, there was a significant difference in VO2 kinetics (τVO2) between HBRi (39.2 ± 9.2 sec) and HBRn (34.8 ± 8.8 sec) at on-transition (p < 0.05). The relationship between BR and HR during both exercise was clearly significant in HBRn (r = 0.95; r = 0.86, p < 0.01), but was significant in CLE (r = 0.56, p < 0.01) and was not significant only in RLE in HBRi. These results suggest that the change of VO2 occurs to decrease O2 extraction induced by effects on coupling of cardiolocomotor rhythm or to increase VE for washing-in body CO2 stores in HBRi.