Mental fatigue is a complex state that results from prolonged cognitive activity. Symptoms of mental fatigue can include change in mood, motivation, and temporary deterioration of various cognitive functions involved ...Mental fatigue is a complex state that results from prolonged cognitive activity. Symptoms of mental fatigue can include change in mood, motivation, and temporary deterioration of various cognitive functions involved in goal-directed behavior. Extensive research has been done to develop methods for recognizing physiological and psychophysiological signs of mental fatigue. This has allowed the development of many AI-based models to classify different levels of fatigue, using data extracted from eye-tracking device, EEG, or ECG. In this paper, we present an experimental protocol which aims to both generate/measure mental fatigue and provide effective strategies for recuperation via VR sessions paired with EEG and eye tracking devices. This paper first provides a comprehensive state-of-the-art of mental fatigue predictive factors, measurement methods, and recuperation strategies. Then the paper presents an experimental protocol resulting from the state-of-the-art to 1) generate and measure mental fatigue and 2) evaluate the effectiveness of virtual therapy for fatigue recuperation, using a virtual reality (VR) simulated environment. In our work, we successfully generated mental fatigue through completion of cognitive tasks in a virtual simulated environment. Participants showed significant decline in pupil diameter and theta/alpha score during the various cognitive tasks. We trained an RBF SVM classifier from Electroencephalogram (EEG) data classifying mental fatigue with 95% accuracy on the test set. Finally, our results show that the time allocated for virtual therapy did not improve pupil diameter in post-relaxation period. Further research on the impact of relaxation therapy on relaxation therapy should allocate time closer to the standard recovery time of 60 min.展开更多
To investigate the effects of magnetic stimulation at acupoints on brain functional network during mental fatigue, magnetic stimulation was applied to stimulate SHENMEN (HT7), HEGU (LI4) and LAOGONG (PC8) acupoint in ...To investigate the effects of magnetic stimulation at acupoints on brain functional network during mental fatigue, magnetic stimulation was applied to stimulate SHENMEN (HT7), HEGU (LI4) and LAOGONG (PC8) acupoint in this paper. The brain functional networks of normal state, mental fatigue state and stimulated state were constructed and the characteristic parameters were comparatively studied based on the complex network theory. The results showed that the connection of the network was enhanced by stimulating the HT7, LI4 and PC8 acupoint. In conclusion, magnetic stimulation at acupoints can effectively relieve mental fatigue.展开更多
Application of continuous repetition of motor imagery can improve the performance of exercise tasks.However,there is a lack of more detailed neurophysiological evidence to support the formulation of clear standards fo...Application of continuous repetition of motor imagery can improve the performance of exercise tasks.However,there is a lack of more detailed neurophysiological evidence to support the formulation of clear standards for interventions using motor imagery.Moreover,identification of motor imagery intervention time is necessary because it exhibits possible central fatigue.Therefore,the purpose of this study was to elucidate the development of fatigue during continuous repetition of motor imagery through objective and subjective evaluation.The study involved two experiments.In experiment 1,14 healthy young volunteers were required to imagine grasping and lifting a 1.5-L plastic bottle using the whole hand.Each participant performed the motor imagery task 100 times under each condition with 48 hours interval between two conditions:500 mL or 1500 mL of water in the bottle during the demonstration phase.Mental fatigue and a decrease in pinch power appeared under the 1500-mL condition.There were changes in concentration ability or corticospinal excitability,as assessed by motor evoked potentials,between each set with continuous repetition of motor imagery also under the 1500-mL condition.Therefore,in experiment 2,12 healthy volunteers were required to perform the motor imagery task 200 times under the 1500-mL condition.Both concentration ability and corticospinal excitability decreased.This is the first study to show that continuous repetition of motor imagery can decrease corticospinal excitability in addition to producing mental fatigue.This study was approved by the Institutional Ethics Committee at the Nagasaki University Graduate School of Biomedical and Health Sciences(approval No.18121302)on January 30,2019.展开更多
Nowadays, there is a great need to investigate the effects of fatigue on physical as well as mental performance. The issues that are generally associated with extreme fatigue are that one can easily lose one’s focus ...Nowadays, there is a great need to investigate the effects of fatigue on physical as well as mental performance. The issues that are generally associated with extreme fatigue are that one can easily lose one’s focus while performing any particular activity whether it is physical or mental and this decreases one’s motivation to complete the task at hand efficiently and successfully. In the same line of thought, myriads of research studies posited the negative effects of fatigue on mental performance, and most techniques to induce fatigue to require normally long-time and repetitive visual search tasks. In this study, a visual search algorithm task was devised and customized using performance measures such as <em>d</em>’ (<strong>d-prime</strong>) and Speed Accuracy Trade-Off (<strong>SATF</strong>) as well as <strong>ROC</strong> analysis for classifier performance. The visual search algorithm consisted of distractors (<strong>L</strong>) and a target (<strong>T</strong>) whereby human participants had to press the appropriate keyboard button as fast as possible if they notice a target or not upon presentation of a visual stimulus. It was administered to human participants under laboratory conditions, and the reaction times, as well as accuracy of the participants, were monitored. It was found that the test image Size35Int255 was the best image to be used in terms of sensitivity and AUC (Area under Curve). Therefore, ongoing researches can use these findings to create their visual stimuli in such a way that the target and distractor images follow the size and intensity characteristics as found in this research.展开更多
Background: Cognitive impairments as sequelae of brain injury are common and can negatively affect activities of everyday life, participation and quality of life. Thus, finding ways to reduce cognitive impairments and...Background: Cognitive impairments as sequelae of brain injury are common and can negatively affect activities of everyday life, participation and quality of life. Thus, finding ways to reduce cognitive impairments and ameliorate their negative impact on everyday life is an important focus of research. Aim: The aim of this pilot study was to analyse the effects of a combination of guided mindfulness and aerobic exercise on cognitive ability and mental fatigue in patients with acquired brain injury (ABI). Design: Pilot study, with a before-after design. Setting: Outpatient. Population: Twenty-one patients suffering from ABI, former patients of three rehabilitation medicine departments. Methods: The intervention comprised a structured combination of guided mindfulness program and outdoor walking, three times/week for 12 weeks. The outcome measures included assessment of information processing speed, working memory, oxygen uptake and self-reported mental fatigue. Results: The main results showed improvements in cognitive abilities related to information processing speed, perceived mental fatigue and physical capacity. Conclusions: A combination of mindfulness and physical activity can increase information processing speed and ameliorate mental fatigue. Further studies are needed to confirm our findings. Clinical Rehabilitation Impact: The combination of guided mindfulness and physical activity shows promise as a treatment modality in rehabilitation of impaired information processing speed and mental fatigue following ABI.展开更多
Oplopanax elatus(Nakai) Nakai, a member of the ancient angiosperm plant family Araliaceae, is used for the treatment of different disorders in the medicine systems of China, Russia, and Korea, and was designated in Ru...Oplopanax elatus(Nakai) Nakai, a member of the ancient angiosperm plant family Araliaceae, is used for the treatment of different disorders in the medicine systems of China, Russia, and Korea, and was designated in Russia as a classical adaptogen. Despite extensive studies of classical adaptogens, there are comparatively few reports concerning the chemical composition and pharmacological effects of O. elatus in English. The plant is a potential source of saponins, flavonoids, anthraquinones, terpenes, and other active compounds. Experimental studies and clinical applications have indicated that O. elatus possesses a number of pharmacological activities, including adaptogenic, anti-convulsant, anti-diabetic, anti-fungal, anti-inflammatory, anti-oxidant, blood pressure modulating, and reproductive function effects. In this review, the chemistry, safety, and therapeutic potential of O. elatus are summarized and highlighted to encourage the further development of this plant.展开更多
文摘Mental fatigue is a complex state that results from prolonged cognitive activity. Symptoms of mental fatigue can include change in mood, motivation, and temporary deterioration of various cognitive functions involved in goal-directed behavior. Extensive research has been done to develop methods for recognizing physiological and psychophysiological signs of mental fatigue. This has allowed the development of many AI-based models to classify different levels of fatigue, using data extracted from eye-tracking device, EEG, or ECG. In this paper, we present an experimental protocol which aims to both generate/measure mental fatigue and provide effective strategies for recuperation via VR sessions paired with EEG and eye tracking devices. This paper first provides a comprehensive state-of-the-art of mental fatigue predictive factors, measurement methods, and recuperation strategies. Then the paper presents an experimental protocol resulting from the state-of-the-art to 1) generate and measure mental fatigue and 2) evaluate the effectiveness of virtual therapy for fatigue recuperation, using a virtual reality (VR) simulated environment. In our work, we successfully generated mental fatigue through completion of cognitive tasks in a virtual simulated environment. Participants showed significant decline in pupil diameter and theta/alpha score during the various cognitive tasks. We trained an RBF SVM classifier from Electroencephalogram (EEG) data classifying mental fatigue with 95% accuracy on the test set. Finally, our results show that the time allocated for virtual therapy did not improve pupil diameter in post-relaxation period. Further research on the impact of relaxation therapy on relaxation therapy should allocate time closer to the standard recovery time of 60 min.
文摘To investigate the effects of magnetic stimulation at acupoints on brain functional network during mental fatigue, magnetic stimulation was applied to stimulate SHENMEN (HT7), HEGU (LI4) and LAOGONG (PC8) acupoint in this paper. The brain functional networks of normal state, mental fatigue state and stimulated state were constructed and the characteristic parameters were comparatively studied based on the complex network theory. The results showed that the connection of the network was enhanced by stimulating the HT7, LI4 and PC8 acupoint. In conclusion, magnetic stimulation at acupoints can effectively relieve mental fatigue.
文摘Application of continuous repetition of motor imagery can improve the performance of exercise tasks.However,there is a lack of more detailed neurophysiological evidence to support the formulation of clear standards for interventions using motor imagery.Moreover,identification of motor imagery intervention time is necessary because it exhibits possible central fatigue.Therefore,the purpose of this study was to elucidate the development of fatigue during continuous repetition of motor imagery through objective and subjective evaluation.The study involved two experiments.In experiment 1,14 healthy young volunteers were required to imagine grasping and lifting a 1.5-L plastic bottle using the whole hand.Each participant performed the motor imagery task 100 times under each condition with 48 hours interval between two conditions:500 mL or 1500 mL of water in the bottle during the demonstration phase.Mental fatigue and a decrease in pinch power appeared under the 1500-mL condition.There were changes in concentration ability or corticospinal excitability,as assessed by motor evoked potentials,between each set with continuous repetition of motor imagery also under the 1500-mL condition.Therefore,in experiment 2,12 healthy volunteers were required to perform the motor imagery task 200 times under the 1500-mL condition.Both concentration ability and corticospinal excitability decreased.This is the first study to show that continuous repetition of motor imagery can decrease corticospinal excitability in addition to producing mental fatigue.This study was approved by the Institutional Ethics Committee at the Nagasaki University Graduate School of Biomedical and Health Sciences(approval No.18121302)on January 30,2019.
文摘Nowadays, there is a great need to investigate the effects of fatigue on physical as well as mental performance. The issues that are generally associated with extreme fatigue are that one can easily lose one’s focus while performing any particular activity whether it is physical or mental and this decreases one’s motivation to complete the task at hand efficiently and successfully. In the same line of thought, myriads of research studies posited the negative effects of fatigue on mental performance, and most techniques to induce fatigue to require normally long-time and repetitive visual search tasks. In this study, a visual search algorithm task was devised and customized using performance measures such as <em>d</em>’ (<strong>d-prime</strong>) and Speed Accuracy Trade-Off (<strong>SATF</strong>) as well as <strong>ROC</strong> analysis for classifier performance. The visual search algorithm consisted of distractors (<strong>L</strong>) and a target (<strong>T</strong>) whereby human participants had to press the appropriate keyboard button as fast as possible if they notice a target or not upon presentation of a visual stimulus. It was administered to human participants under laboratory conditions, and the reaction times, as well as accuracy of the participants, were monitored. It was found that the test image Size35Int255 was the best image to be used in terms of sensitivity and AUC (Area under Curve). Therefore, ongoing researches can use these findings to create their visual stimuli in such a way that the target and distractor images follow the size and intensity characteristics as found in this research.
文摘Background: Cognitive impairments as sequelae of brain injury are common and can negatively affect activities of everyday life, participation and quality of life. Thus, finding ways to reduce cognitive impairments and ameliorate their negative impact on everyday life is an important focus of research. Aim: The aim of this pilot study was to analyse the effects of a combination of guided mindfulness and aerobic exercise on cognitive ability and mental fatigue in patients with acquired brain injury (ABI). Design: Pilot study, with a before-after design. Setting: Outpatient. Population: Twenty-one patients suffering from ABI, former patients of three rehabilitation medicine departments. Methods: The intervention comprised a structured combination of guided mindfulness program and outdoor walking, three times/week for 12 weeks. The outcome measures included assessment of information processing speed, working memory, oxygen uptake and self-reported mental fatigue. Results: The main results showed improvements in cognitive abilities related to information processing speed, perceived mental fatigue and physical capacity. Conclusions: A combination of mindfulness and physical activity can increase information processing speed and ameliorate mental fatigue. Further studies are needed to confirm our findings. Clinical Rehabilitation Impact: The combination of guided mindfulness and physical activity shows promise as a treatment modality in rehabilitation of impaired information processing speed and mental fatigue following ABI.
文摘Oplopanax elatus(Nakai) Nakai, a member of the ancient angiosperm plant family Araliaceae, is used for the treatment of different disorders in the medicine systems of China, Russia, and Korea, and was designated in Russia as a classical adaptogen. Despite extensive studies of classical adaptogens, there are comparatively few reports concerning the chemical composition and pharmacological effects of O. elatus in English. The plant is a potential source of saponins, flavonoids, anthraquinones, terpenes, and other active compounds. Experimental studies and clinical applications have indicated that O. elatus possesses a number of pharmacological activities, including adaptogenic, anti-convulsant, anti-diabetic, anti-fungal, anti-inflammatory, anti-oxidant, blood pressure modulating, and reproductive function effects. In this review, the chemistry, safety, and therapeutic potential of O. elatus are summarized and highlighted to encourage the further development of this plant.