There are individual differences in the recall of motor imagery, and various methods are being studied. Mental rotation (MR) task is one of them. Kinesthetic motor imagery are involved in MR using body parts, and it is reported that reaction time is prolonged at angles where biomechanical restriction occurs. However, due to differences in body parts and individual characteristics used in MR tasks, different characteristics are seen in prolongation of response time, and it is conceivable that both visual-motor imagery and kinesthetic motor imagery are involved. Therefore, in this study, the characteristics of the body part and angle are clarified by stimulation of all parts of the hands and feet, which are used in MR tasks that stimulate the body part as a stimulus. We investigated the involvement of the motor imagery at the time of task on each part and aimed to grasp the suitability as a stimulus.
Subjects were 24 girls with right handedness. As the stimulation of MR tasks, images (0°, 60°, 120°, 180°, 240°, 300°) obtained by rotating right and left photographs of the hands (palm side and back side) and feet (bottom side and back side) was used. As a result, on the dorsal side of the limbs, the response time was prolonged at 180°, and the reaction time was prolonged at the palm side and the plantar side at an angle difficult to actually move. Based on the results of this study, assuming the utilization of MR to grasp the affinity to the body and the body figure of the body, using both the front and back of the hand as a stimulus photograph, the relationship of reaction time and error rate at each angle It is suggested that it is important to pay attention to.
Evaluation of sleep onset difficulty by polysomnography with the standard sleep stage criteria by Rechtschaffen and Kales often shows that sleep problem marked by difficulty falling asleep shares the same structure as normal sleep onset period (SOP). This study aimed to clarify whether objective features during SOP of the patients with difficulty falling asleep were different from those of normal control. Objective criteria established for the nine electroencephalogram (EEG) stages and autonomic nervous activity were used to confirm subjective complaints of difficulty falling asleep. Both of psychophysiological insomnia (PPI) and normal control group had 7 participants each. As a result, the PPI group showed significantly longer latencies of each EEG stage from H4 to H8 and longer durations of H2, H3, and H5 than the normal control group. Additionally, higher mean LF/HF ratios, indicating sympathetic nervous activity, were observed at the time of each EEG stage's first appearance during SOP in the PPI group. Our results may indicate the combination of indices used in this study could reflect the more detailed changes inherent in the sleep onset process and contribute to investigate subjective difficulty falling asleep.
Mental faculties are a key factor for achieving optimal performance in sports. The purpose of this study was to clarify the subitizing performance in ice hockey players of open-skill sports, and how this differs by their position by using N2 and P3, which are event-related brain potentials (ERPs) elicited by subitizing based enumeration. The participants were 14 young Japanese males who agreed to participate in the study for course credit. They were divided to the athlete (n＝7) or control (n＝7) group. In Experiment 1, the subitizing task stimuli included 30 random patterns containing anywhere from 3 to 12 ice hockey player silhouettes ; in Experiment 2, the silhouettes were replaced by circle figures. Participants were instructed to press a button with their right hand and verbally provide the number of stimuli on the display screen when they knew that number with simultaneous electroencephalography (EEG) recording. There was no apparent behavioral difference between athletes and controls. However, among the athletes, goalkeepers were observed to respond more accurately than did field players. The amplitude of the second negative component (N2) differed between the athlete and control groups over the frontal and central area and was greater in the former group. Our findings suggest that the athlete group exhibited faster subitizing than did the control group. P3 amplitude was larger when a smaller number of items were enumerated by subitizing than when 5 or more items were presented, reflecting the allocation of attention to the silhouettes/circle figures. These findings suggest that N2 amplitude may detect the difference between athlete and control, that P3 amplitude can identify whether the enumerating is performed by subitizing or counting, and that the enumerating accuracy might be useful as a measure of the quick enumerating skill of the ice hockey players who requires good subitizing skills.
In open-skill sports, athletes are required to perceive their ever-changing environment faster and more accurately, and to subsequently select more appropriate behaviors. Several psychological operations are thought to play a role in athletes' cognitive processes, of which mental rotation is one. Matsumoto et al. (2017) have examined the behavioral and cognitive characteristics of open-skill athletes during a mental rotation task by examining the relationship between task performance and rotation related negativity (RRN), which is considered to reflect the process of mental rotation. However, the preparation of task seems to be not a little related to the task performance. The contingent negative variation (CNV) is a slow negative brainwave that develops during the time interval between a warning stimulus and an imperative stimulus. The changes in amplitude depend on the expectation, attention, or motor preparation for the imperative stimulus. The purpose of this study was to preliminarily evaluate the behavioral and cognitive characteristics of open-skill athletes during the preparation for the task by examining the relationship between task performance and CNV amplitudes obtained from the electroencephalogram (EEG) of skilled ice hockey players (athlete group) and sedentary students (control group). We calculated the percentage and mean reaction time (RT) of the correct responses as well as the mean CNV amplitude, for which waveforms were obtained by separately averaging the electrocortical data from the warning stimulus to the imperative stimulus for the first and second half-sets of the trials, and subsequently analyzed the relationship between these measurements. The athlete group responded less accurately but faster than the control group, although both groups responded more accurately and faster in the first half-set than in the second half-set. No significant time difference in CNV amplitude was found between the first and second half-sets in the athlete group, while the control group showed larger right parietal CNV amplitude in the second half-set than in the first half-set. These findings indicated that open-skill athletes prioritized speed over accuracy and that their performance may have been improved due to the successful process following the presentation of the imperative stimulus, rather than the sufficient preparation of the task.
Biofeedback (BF) treatments have some effects on intractable diseases but they often slow and easy to fade away. On the other hand many peripheral nerve stimulations have sometimes direct and fast effects in several cases. We have tried to combine the two methods (H-BF : Hybrid Bio-Feedback) in order to improve the BF treatment including Alzheimer dementia and Parkinson tremor. The H-BF for tremor shows the normalization of tremor frequency as well as decreasing of tremor intensity. The H-BF of light/electric/mechanical stimulation with pupil image BF for dementia shows improvement on HDS-R, MMSE, POMS and BPSD. The reason for the dominance of H-BF may be that the peripheral stimulation (PS) can collaborate with BF to enforce both conditional and unconditional stimulus, which enables to produce stronger responses, comparing single treatment of BF or PS.