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Rao Y, Zhang L, Jing R, Huo J, Yan K, He J, Hou X, Mu J, Geng W, Cui H, Hao Z, Zan X, Ma J, Chou X. An optimized EEGNet decoder for decoding motor image of four class fingers flexion. Brain Res 2024; 1841:149085. [PMID: 38876320 DOI: 10.1016/j.brainres.2024.149085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 05/23/2024] [Accepted: 06/10/2024] [Indexed: 06/16/2024]
Abstract
As a cutting-edge technology of connecting biological brain and external devices, brain-computer interface (BCI) exhibits promising applications on extensive fields such as medical and military. As for the disable individuals with four limbs losing the motor functions, it is a potential treatment way to drive mechanical equipments by the means of non-invasive BCI, which is badly depended on the accuracy of the decoded electroencephalogram (EEG) singles. In this study, an explanatory convolutional neural network namely EEGNet based on SimAM attention module was proposed to enhance the accuracy of decoding the EEG singles of index and thumb fingers for both left and right hand using sensory motor rhythm (SMR). An average classification accuracy of 72.91% the data of eight healthy subjects was obtained, which were captured from the one second before finger movement to two seconds after action. Furthermore, the character of event-related desynchronization (ERD) and event related synchronization (ERS) of index and thumb fingers was also studied in this study. These findings have significant importance for controlling external devices or other rehabilitation equipment using BCI in a fine way.
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Affiliation(s)
- Yongkang Rao
- Science and Technology on Electronic Test and Measurement Laboratory, North University of China, Taiyuan 030051, China
| | - Le Zhang
- Science and Technology on Electronic Test and Measurement Laboratory, North University of China, Taiyuan 030051, China
| | - Ruijun Jing
- Science and Technology on Electronic Test and Measurement Laboratory, North University of China, Taiyuan 030051, China
| | - Jiabing Huo
- Science and Technology on Electronic Test and Measurement Laboratory, North University of China, Taiyuan 030051, China
| | - Kunxian Yan
- Science and Technology on Electronic Test and Measurement Laboratory, North University of China, Taiyuan 030051, China
| | - Jian He
- Science and Technology on Electronic Test and Measurement Laboratory, North University of China, Taiyuan 030051, China
| | - Xiaojuan Hou
- Science and Technology on Electronic Test and Measurement Laboratory, North University of China, Taiyuan 030051, China
| | - Jiliang Mu
- Science and Technology on Electronic Test and Measurement Laboratory, North University of China, Taiyuan 030051, China
| | - Wenping Geng
- Science and Technology on Electronic Test and Measurement Laboratory, North University of China, Taiyuan 030051, China
| | - Haoran Cui
- Science and Technology on Electronic Test and Measurement Laboratory, North University of China, Taiyuan 030051, China
| | - Zeyu Hao
- Science and Technology on Electronic Test & Measurement Laboratory, The 41st Institute of China Electronic Technology Group Corporation, Qingdao 266555, China
| | - Xiang Zan
- Shanxi Provincial People's Hospital, the Fifth Clinical Medical College of Shanxi Medical University, Taiyuan 030012, China
| | - Jiuhong Ma
- Shanxi Provincial People's Hospital, the Fifth Clinical Medical College of Shanxi Medical University, Taiyuan 030012, China
| | - Xiujian Chou
- Science and Technology on Electronic Test and Measurement Laboratory, North University of China, Taiyuan 030051, China
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Lambert KJM, Chen YY, Donoff C, Elke J, Madan CR, Singhal A. Handedness effects on imagery of dominant- versus non-dominant-hand movements: An electroencephalographic investigation. Eur J Neurosci 2023; 58:3286-3298. [PMID: 37501346 DOI: 10.1111/ejn.16096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 05/26/2023] [Accepted: 07/05/2023] [Indexed: 07/29/2023]
Abstract
Mental representations of our bodies are thought to influence how we interact with our surroundings. We can examine these mental representations through motor imagery, the imagination of movement using scalp EEG recordings. The visual modality of motor imagery emphasises 'seeing' the imagined movement and is associated with increased activity in the alpha rhythm (8-14 Hz) measured over the occipital regions. The kinaesthetic modality emphasises 'feeling' the movement and is associated with decreased activity in the mu rhythm (8-14 Hz) measured over the sensorimotor cortices. These two modalities can be engaged in isolation or together. We recorded EEG activity while 37 participants (17 left-hand dominant) completed an objective hand motor imagery task. Left-handers exhibited significant activity differences between occipital and motor regions only during imagery of right-hand (non-dominant-hand) movements. This difference was primarily driven by less oscillatory activity in the mu rhythm, which may reflect a shift in imagery strategy wherein participants placed more effort into generating the kinaesthetic sensations of non-dominant-hand imagery. Spatial features of 8-14 Hz activity generated from principal component analysis (PCA) provide further support for a strategy shift. Right-handers also exhibited significant differences between alpha and mu activity during imagery of non-dominant movements. However, this difference was not primarily driven by either rhythm, and no differences were observed in the group's PCA results. Together, these findings indicate that individuals imagine movement differently when it involves their dominant versus non-dominant hand, and left-handers may be more flexible in their motor imagery strategies.
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Affiliation(s)
- Kathryn J M Lambert
- Department of Occupational Therapy, University of Alberta, Edmonton, Alberta, Canada
| | - Yvonne Y Chen
- Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Christopher Donoff
- Department of Psychology, University of Alberta, Edmonton, Alberta, Canada
| | - Jonah Elke
- Department of Psychology, University of Alberta, Edmonton, Alberta, Canada
| | | | - Anthony Singhal
- Department of Psychology, University of Alberta, Edmonton, Alberta, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
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Fujiwara K, Shibata M, Awano Y, Iso N, Shibayama K, Higashi T. Differences in Cortical Area Activity and Motor Imagery Vivid-Ness during Evaluation of Motor Imagery Tasks in Right and Left Hemiplegics. Brain Sci 2023; 13:brainsci13050748. [PMID: 37239220 DOI: 10.3390/brainsci13050748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 04/18/2023] [Accepted: 04/28/2023] [Indexed: 05/28/2023] Open
Abstract
The ability to develop vivid motor imagery (MI) is important for effective mental practice. Therefore, we aimed to determine differences in the MI clarity and cortical area activity between patients with right hemiplegia and left hemiplegia after stroke in an MI task. In total, 11 participants with right hemiplegia and 14 with left hemiplegia were categorized into two groups. The MI task required the flexion and extension of the finger on the paralyzed side. Considering that MI vividness changes with MI practice, we measured the MI vividness and cortical area activity during the task before and after MI practice. MI vividness was evaluated subjectively using the visual analog scale, and cerebral hemodynamics during the task were measured using near-infrared spectroscopy in cortical regions during the MI task. The MI sharpness and cortical area activity in the MI task were significantly lower in the right hemiplegia group than in the left hemiplegia group. Therefore, when practicing mental practices with right hemiplegia, it is necessary to devise ways by which to increase MI vividness.
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Affiliation(s)
- Kengo Fujiwara
- Medical Corporation Zeshinkai Nagasaki Rehabilitation Hospital, Nagasaki 850-0854, Japan
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8520, Japan
| | - Masatomo Shibata
- Medical Corporation Zeshinkai Nagasaki Rehabilitation Hospital, Nagasaki 850-0854, Japan
| | - Yoshinaga Awano
- School Corporation Tamaki Gakuen Nagasaki College of Medical Technology, Nagasaki 850-0822, Japan
| | - Naoki Iso
- Faculty of Health Sciences, Tokyo Kasei University, Saitama 350-1398, Japan
| | - Koji Shibayama
- Medical Corporation Zeshinkai Nagasaki Rehabilitation Hospital, Nagasaki 850-0854, Japan
| | - Toshio Higashi
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8520, Japan
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Readman MR, Crawford TJ, Linkenauger SA, Bek J, Poliakoff E. Motor imagery vividness and symptom severity in Parkinson's disease. J Neuropsychol 2023; 17:180-192. [PMID: 36229225 PMCID: PMC10946738 DOI: 10.1111/jnp.12293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 09/12/2022] [Accepted: 09/13/2022] [Indexed: 11/28/2022]
Abstract
Motor imagery (MI), the mental simulation of movement in the absence of overt motor output, has demonstrated potential as a technique to support rehabilitation of movement in neurological conditions such as Parkinson's disease (PD). Existing evidence suggests that MI is largely preserved in PD, but previous studies have typically examined global measures of MI and have not considered the potential impact of individual differences in symptom presentation on MI. The present study investigated the influence of severity of overall motor symptoms, bradykinesia and tremor on MI vividness scores in 44 individuals with mild to moderate idiopathic PD. Linear mixed effects modelling revealed that imagery modality and the severity of left side bradykinesia significantly influenced MI vividness ratings. Consistent with previous findings, participants rated visual motor imagery (VMI) to be more vivid than kinesthetic motor imagery (KMI). Greater severity of left side bradykinesia (but not right side bradykinesia) predicted increased vividness of KMI, while tremor severity and overall motor symptom severity did not predict vividness of MI. The specificity of the effect of bradykinesia to the left side may reflect greater premorbid vividness for the dominant (right) side or increased attention to more effortful movements on the left side of the body resulting in more vivid motor imagery.
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Affiliation(s)
| | | | | | - Judith Bek
- Centre for Motor Control, Faculty of Kinesiology & Physical Education, University of Toronto, Toronto, ON, Canada
- Division of Psychology, Communication and Human Neuroscience, School of Health Sciences., University of Manchester, Manchester, UK
| | - Ellen Poliakoff
- Division of Psychology, Communication and Human Neuroscience, School of Health Sciences., University of Manchester, Manchester, UK
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Immediate Effects of Fine-Motor Training on Coordination and Dexterity of the Non-Dominant Hand in Healthy Adults: A Randomized Controlled Trial. Behav Sci (Basel) 2022; 12:bs12110446. [PMID: 36421742 PMCID: PMC9687507 DOI: 10.3390/bs12110446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 10/30/2022] [Accepted: 11/10/2022] [Indexed: 11/16/2022] Open
Abstract
Several studies have demonstrated the beneficial effects of mirror training; however, only a few studies in Eastern countries have investigated fine-motor exercises using chopsticks, which have numerous advantages. We aimed to compare changes in coordination and dexterity of the non-dominant hand in healthy adults after conducting fine-motor training with the dominant hand using a mirror. We divided 100 healthy adults (age: 20−40 years) into experimental and control groups (each n = 50). The experimental group placed the non-dominant hand in a mirror box and indirectly imitated the fine-motor exercises conducted with the dominant hand using chopsticks. The control group performed the task with the non-dominant hand using chopsticks. We conducted the Chopsticks Manipulation Test and the Purdue Pegboard Test to assess the pre- and post-intervention coordination and dexterity of the non-dominant hand. Both groups showed a significant post-intervention improvement in coordination and dexterity (p < 0.01). There was no significant between-group difference in the functional improvement of coordination and dexterity (p > 0.05). Fine-motor training using mirrors and chopsticks significantly improved coordination and dexterity of the non-dominant hand. This training could be used to improve activity in brain regions associated with the non-dominant hand in healthy adults.
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Fujiwara K, Shibata M, Awano Y, Shibayama K, Iso N, Matsuo M, Nakashima A, Moriuchi T, Mitsunaga W, Higashi T. A method for using video presentation to increase the vividness and activity of cortical regions during motor imagery tasks. Neural Regen Res 2021; 16:2431-2437. [PMID: 33907031 PMCID: PMC8374587 DOI: 10.4103/1673-5374.313058] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 09/29/2020] [Accepted: 10/15/2020] [Indexed: 11/07/2022] Open
Abstract
In recent years, mental practice (MP) using laterally inverted video of a subject's non-paralyzed upper limb to improve the vividness of presented motor imagery (MI) has been shown to be effective for improving the function of a paralyzed upper limb. However, no studies have yet assessed the activity of cortical regions engaged during MI task performance using inverse video presentations and neurophysiological indicators. This study sought to investigate changes in MI vividness and hemodynamic changes in the cerebral cortex during MI performance under the following three conditions in near-infrared spectroscopy: MI-only without inverse video presentation (MI-only), MI with action observation (AO) of an inverse video presentation of another person's hand (AO + MI (other hand)), and MI with AO of an inverse video presentation of a participant's own hand (AO + MI (own hand)). Participants included 66 healthy right-handed adults (41 men and 25 women; mean age: 26.3 ± 4.3 years). There were 23 patients in the MI-only group (mean age: 26.4 ± 4.1 years), 20 in the AO + MI (other hand) group (mean age: 25.9 ± 5.0 years), and 23 in the AO + MI (own hand) group (mean age: 26.9 ± 4.1 years). The MI task involved transferring 1 cm × 1 cm blocks from one plate to another, once per second, using chopsticks held in the non-dominant hand. Based on a visual analog scale (VAS), MI vividness was significantly higher in the AO + MI (own hand) group than in the MI-only group and the AO + MI (other hand) group. A main effect of condition was revealed in terms of MI vividness, as well as regions of interest (ROIs) in certain brain areas associated with motor processing. The data suggest that inverse video presentation of a person's own hand enhances the MI vividness and increases the activity of motor-related cortical areas during MI. This study was approved by the Institutional Ethics Committee of Nagasaki University Graduate School of Biomedical and Health Sciences (approval No. 18121303) on January 18, 2019.
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Affiliation(s)
- Kengo Fujiwara
- Department of Clinical Services, Nagasaki Rehabilitation Hospital, Nagasaki, Japan
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Masatomo Shibata
- Department of Clinical Services, Nagasaki Rehabilitation Hospital, Nagasaki, Japan
| | - Yoshinaga Awano
- Department of Clinical Services, Nagasaki Rehabilitation Hospital, Nagasaki, Japan
| | - Koji Shibayama
- Department of Clinical Services, Nagasaki Rehabilitation Hospital, Nagasaki, Japan
| | - Naoki Iso
- Department of Rehabilitation, Faculty of Health Sciences, Tokyo Kasei University, Tokyo, Japan
| | - Moemi Matsuo
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Akira Nakashima
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Takefumi Moriuchi
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Wataru Mitsunaga
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Toshio Higashi
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
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Iso N, Moriuchi T, Fujiwara K, Matsuo M, Mitsunaga W, Hasegawa T, Iso F, Cho K, Suzuki M, Higashi T. Hemodynamic Signal Changes During Motor Imagery Task Performance Are Associated With the Degree of Motor Task Learning. Front Hum Neurosci 2021; 15:603069. [PMID: 33935666 PMCID: PMC8081959 DOI: 10.3389/fnhum.2021.603069] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Accepted: 03/12/2021] [Indexed: 12/19/2022] Open
Abstract
Purpose This study aimed to investigate whether oxygenated hemoglobin (oxy-Hb) generated during a motor imagery (MI) task is associated with the motor learning level of the task. Methods We included 16 right-handed healthy participants who were trained to perform a ball rotation (BR) task. Hemodynamic brain activity was measured using near-infrared spectroscopy to monitor changes in oxy-Hb concentration during the BR MI task. The experimental protocol used a block design, and measurements were performed three times before and after the initial training of the BR task as well as after the final training. The BR count during training was also measured. Furthermore, subjective vividness of MI was evaluated three times after NIRS measurement using the Visual Analog Scale (VAS). Results The results showed that the number of BRs increased significantly with training (P < 0.001). VAS scores also improved with training (P < 0.001). Furthermore, oxy-Hb concentration and the region of interest (ROI) showed a main effect (P = 0.001). An interaction was confirmed (P < 0.001), and it was ascertained that the change in oxy-Hb concentrations due to training was different for each ROI. The most significant predictor of subjective MI vividness was supplementary motor area (SMA) oxy-Hb concentration (coefficient = 0.365). Discussion Hemodynamic brain activity during MI tasks may be correlated with task motor learning levels, since significant changes in oxy-Hb concentrations were observed following initial and final training in the SMA. In particular, hemodynamic brain activity in the SMA was suggested to reflect the MI vividness of participants.
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Affiliation(s)
- Naoki Iso
- Faculty of Health Sciences, Tokyo Kasei University, Saitama, Japan
| | - Takefumi Moriuchi
- Department of Occupational Therapy, Nagasaki University Graduate School of Biomedical Sciences and Health Sciences, Nagasaki, Japan
| | - Kengo Fujiwara
- Department of Health Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Moemi Matsuo
- Department of Health Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Wataru Mitsunaga
- Department of Health Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Takashi Hasegawa
- Department of Health Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Fumiko Iso
- Department of Health Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Kilchoon Cho
- Faculty of Health Sciences, Tokyo Kasei University, Saitama, Japan
| | - Makoto Suzuki
- Faculty of Health Sciences, Tokyo Kasei University, Saitama, Japan
| | - Toshio Higashi
- Department of Health Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
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Matsuo M, Iso N, Fujiwara K, Moriuchi T, Matsuda D, Mitsunaga W, Nakashima A, Higashi T. Comparison of cerebral activation between motor execution and motor imagery of self-feeding activity. Neural Regen Res 2021; 16:778-782. [PMID: 33063742 PMCID: PMC8067926 DOI: 10.4103/1673-5374.295333] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Motor imagery is defined as an act wherein an individual contemplates a mental action of motor execution without apparent action. Mental practice executed by repetitive motor imagery can improve motor performance without simultaneous sensory input or overt output. We aimed to investigate cerebral hemodynamics during motor imagery and motor execution of a self-feeding activity using chopsticks. This study included 21 healthy right-handed volunteers. The self-feeding activity task comprised either motor imagery or motor execution of eating sliced cucumber pickles with chopsticks to examine eight regions of interest: pre-supplementary motor area, supplementary motor area, bilateral prefrontal cortex, premotor area, and sensorimotor cortex. The mean oxyhemoglobin levels were detected using near-infrared spectroscopy to reflect cerebral activation. The mean oxyhemoglobin levels during motor execution were significantly higher in the left sensorimotor cortex than in the supplementary motor area and the left premotor area. Moreover, significantly higher oxyhemoglobin levels were detected in the supplementary motor area and the left premotor area during motor imagery, compared to motor execution. Supplementary motor area and premotor area had important roles in the motor imagery of self-feeding activity. Moreover, the activation levels of the supplementary motor area and the premotor area during motor execution and motor imagery are likely affected by intentional cognitive processes. Levels of cerebral activation differed in some areas during motor execution and motor imagery of a self-feeding activity. This study was approved by the Ethical Review Committee of Nagasaki University (approval No. 18110801) on December 10, 2018.
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Affiliation(s)
- Moemi Matsuo
- Unit of Medical Science, Nagasaki University Graduate School of Biomedical Sciences; Center for Child Mental Health Care and Education, Nagasaki University, Nagasaki, Japan
| | - Naoki Iso
- Department of Rehabilitation, Faculty of Health Sciences, Tokyo Kasei University, Saitama, Japan
| | - Kengo Fujiwara
- Unit of Medical Science, Nagasaki University Graduate School of Biomedical Sciences; Zeshinkai General Incorporated Association, Nagasaki Rehabilitation Hospital, Nagasaki, Japan
| | - Takefumi Moriuchi
- Unit of Medical Science, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Daiki Matsuda
- Unit of Medical Science, Nagasaki University Graduate School of Biomedical Sciences; The Japanese Red Cross, Nagasaki Genbaku Hospital, Nagasaki, Japan
| | - Wataru Mitsunaga
- Unit of Medical Science, Nagasaki University Graduate School of Biomedical Sciences; Unit of Rehabilitation, Nagasaki University Hospital, Nagasaki, Japan
| | - Akira Nakashima
- Unit of Medical Science, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Toshio Higashi
- Unit of Medical Science, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
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Velasquez-Martinez L, Caicedo-Acosta J, Castellanos-Dominguez G. Entropy-Based Estimation of Event-Related De/Synchronization in Motor Imagery Using Vector-Quantized Patterns. ENTROPY 2020; 22:e22060703. [PMID: 33286475 PMCID: PMC7517241 DOI: 10.3390/e22060703] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/23/2020] [Accepted: 05/26/2020] [Indexed: 02/07/2023]
Abstract
Assessment of brain dynamics elicited by motor imagery (MI) tasks contributes to clinical and learning applications. In this regard, Event-Related Desynchronization/Synchronization (ERD/S) is computed from Electroencephalographic signals, which show considerable variations in complexity. We present an Entropy-based method, termed VQEnt, for estimation of ERD/S using quantized stochastic patterns as a symbolic space, aiming to improve their discriminability and physiological interpretability. The proposed method builds the probabilistic priors by assessing the Gaussian similarity between the input measured data and their reduced vector-quantized representation. The validating results of a bi-class imagine task database (left and right hand) prove that VQEnt holds symbols that encode several neighboring samples, providing similar or even better accuracy than the other baseline sample-based algorithms of Entropy estimation. Besides, the performed ERD/S time-series are close enough to the trajectories extracted by the variational percentage of EEG signal power and fulfill the physiological MI paradigm. In BCI literate individuals, the VQEnt estimator presents the most accurate outcomes at a lower amount of electrodes placed in the sensorimotor cortex so that reduced channel set directly involved with the MI paradigm is enough to discriminate between tasks, providing an accuracy similar to the performed by the whole electrode set.
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