In order to improve the activation of the mirror neuron system and the ability of the visual-cued motor imagery further, the multi-stimuli-cued unilateral lower limb motor imagery is studied in this paper. The visual-auditory evoked pathway is proposed and the sensory process is studied. To analyze the visual-auditory interactions, the kinesthetic motor imagery with the visual-auditory stimulus, visual stimulus and no stimulus are involved. The motor-related rhythm suppression is applied on quantitative evaluation. To explore the statistical sensory process, the causal relationships among the functional areas and the event-related potentials are investigated. The results have demonstrated the outstanding performances of the visual-auditory evoked motor imagery on the improvement of the mirror neuron system activation and the motor imagery ability. Besides, the abundant information interactions among functional areas and the positive impacts of the auditory stimulus in the motor and the visual areas have been revealed. The possibility that the sensory processes evoked by the visual-auditory interactions differ from the one elicited by kinesthetic motor imagery, has also been indicated. This study will promisingly offer an efficient way to motor rehabilitation, thus favorable for hemiparesis and partial paralysis patients.

Mental fatigue is a common psychobiological state elected by prolonged cognitive activities. Although, the performance and the disadvantage of the mental fatigue have been well known, its connectivity among the multiareas of the brain has not been thoroughly studied yet. This is important for the clarification of the mental fatigue mechanism. However, the common method of connectivity analysis based on EEG cannot get rid of the interference from strong noise. In this paper, an adaptive feature extraction model based on stacked denoising autoencoder has been proposed. The signal to noise ratio of the extracted feature has been analyzed. Compared with principal component analysis, the proposed method can significantly improve the signal to noise ratio and suppress the noise interference. The proposed method has been applied on the analysis of mental fatigue connectivity. The causal connectivity among the frontal, motor, parietal, and visual areas under the awake, fatigue, and sleep deprivation conditions has been analyzed, and different patterns of connectivity between conditions have been revealed. The connectivity direction under awake condition and sleep deprivation condition is opposite. Moreover, there is a complex and bidirectional connectivity relationship, from the anterior areas to the posterior areas and from the posterior areas to the anterior areas, under fatigue condition. These results imply that there are different brain patterns on the three conditions. This study provides an effective method for EEG analysis. It may be favorable to disclose the underlying mechanism of mental fatigue by connectivity analysis.

Autonomous sensory meridian response is believed as a perceptual phenomenon to specific sensory stimuli. To explore the underlying mechanism and emotional effect, the EEG under video and audio triggers of autonomous sensory meridian response was analyzed. The differential entropy and power spectral density by Burg method on δ, θ, α, β, γ and high γ frequencies were employed as quantitative features. The results indicate that the modulation of autonomous sensory meridian response on brain activities is broadband. Video trigger owns better performance of autonomous sensory meridian response than other triggers. Moreover, the results also reveal that autonomous sensory meridian response has a close relationship with neuroticism and its three sub-dimensions, anxiety, self-consciousness and vulnerability, with the scores of self-rating depression scale, but without emotions, happiness, sadness, or fear. This suggests that the responders of autonomous sensory meridian response may have the tendencies of neuroticism and depressive disorder.

Motor imagery (MI) as an important way of motor learning has been studied widely. The visual task stimulus is an efficient way to improve MI abilities; however, its impact mechanism on motor training is still obscure. This study aimed to explore the influence of visual task stimulus on MI during continuous training. Three types of kinesthetic motor imageries, including a visual task stimulus, a visual stimulus, or no stimulus, were assessed. Brain lateralization and the variations of the event-related desynchronization were investigated. The results demonstrated a greater improvement motor performance after a visual task stimulus. The MI evoked by the visual task shows the most complex event-related lateralization (ERL) among the three contexts, with the presence of many ERL components. These results reveal a complex process of planning, attention focusing, and information processing on the brain, and the complexity of the information process increases with the one of external visual stimulus. This work provides a promising foundation for the incorporation of visual-task stimuli as a strategy to improve motor ability during motor training and motor rehabilitation.

Motor imagery has been commonly studied as a means of motor rehabilitation but, the individual differences limit its practical application. Visually evoked motor imagery has been widely highlighted by researchers because of its vivid stimulus. However, this modality is still not applicable to all persons. In this study, we studied the different performances of the visually evoked motor imagery between subjects and tried to explore the personality manifestation which can result in this performance. We found that conscientiousness and openness have negative connections with the performance of visually evoked motor imagery. To compare with spontaneous motor imagery, the visually evoked motor imagery reflects less personality difference between subjects with good and bad performances on motor imagery. This indicate that visually stimulus may increase the pervasive application of motor imagery. This study may provide benefits to predict the rehabilitation effect and to rapidly select the suitable motor rehabilitation methods.

Psychosocial stress refers to the subjective experience and appraisal of real or potentially threatening psychosocial conditions. Pain is a complex physiological and psychological phenomenon, referring to unpleasant sensory and emotional experience associated with actual or potential tissue damage. To investigate the impact of chronic psychosocial stress on neural circuit responses to thermal pain, this study analyzed corticomuscular activities by electroencephalograph and electromyography. The results demonstrate that chronic psychosocial stress can change the cortical synchronization at α and γ frequencies and enhance motor unit recruitment under heat pain at both initial and progressive stages. Moreover, under progressive stimulation, pain-related neural feedback and localization functions may be disrupted, presenting impaired corticomuscular coherence. Therefore, chronic psychosocial stress can alter the integrated processing across both central and peripheral pathways, indicating a disintegration of the cortical-motor integration function of heat pain at initial and progressive stages.