Published papers

Electroencephalogram-based brain–computer interfaces (BCI) have been used as a potential tool for training volitional regulation of corticomuscular drive in patients who have severe hemiplegia due to stroke. However, it is unclear whether ERD observed while attempting motor execution can be regarded as a neural marker that represents M1 excitability in survivors of severe stroke. Therefore we investigated the association between ERD and the blood-oxygen-level-dependent (BOLD) fMRI signal during attempted movement of a paralyzed finger in stroke patients. Nine chronic stroke patients received BCI training for finger extension movement 1 h daily for a duration of 1 month. The sensorimotor rhythm was recorded from the sensorimotor area of the damaged hemisphere, and ongoing amplitude variations were monitored using a BCI system. Either a visual alert or the action of a motor-driven orthosis was triggered in response to ERD of the sensorimotor rhythm while patients attempted extension movements of the paralyzed fingers. Inter-subject covariance between ERD and the BOLD response in the sensorimotor areas was calculated. After BCI training, an increased ERD over the damaged hemisphere was confirmed in all participants while they attempted extension of the affected finger and this increase was associated with a BOLD response in primary sensorimotor area. Whole-brain MRI revealed that the primary sensorimotor area and supplementary motor area were activated in the damaged hemisphere after 1 month of BCI training. ERD reflects the BOLD responses of the primary motor areas in either hemisphere while patients who have severe chronic hemiplegia due to a stroke attempt an extension movement of the paralyzed fingers. One month of BCI can alter motor-related brain area activation. Combining BCI with other methods to facilitate such changes may help to implement BCI for motor rehabilitation after stroke.

Objective: This study evaluated executive dysfunction in patients with subarachnoid haemorrhage (SAH) using the Behavioural Assessment of the Dysexecutive Syndrome (BADS) and correlated the occurrence of executive dysfunction with cerebral blood flow (CBF) reduction in the frontal lobe as assessed by single photon emission computed tomography (SPECT). Design: Correlational study. Subjects: Twenty-Two patients who underwent microsurgical clipping at least 3 months after SAH. Methods: This study evaluated the BADS and the Wechsler Adult Intelligence Scale-III (WAIS-III). In addition, it assessed activities of daily living (ADL). CBF was evaluated using SPECT. The patients were divided into the following groups according to the results of SPECT: (1) those with reduced CBF in the frontal lobe (reduced CBF group, n = 8) and (2) those with intact CBF (intact CBF group, n = 14). Results: The BADS score was significantly lower in the reduced CBF group compared with that of the intact CBF group, while there was no significant difference in the WAIS-III scores and ADL scale between the two groups. Conclusion: Although this result was conducted with a small sample size, executive dysfunction correlates with reduced CBF in the frontal lobes of SAH patients. A detailed evaluation of executive function is suggested in SAH patients, even if the patient's intelligence test and ADL scale reveal no abnormalities. © 2014 Informa UK Ltd. All rights reserved: reproduction in whole or part not permitted.

OBJECTIVE: The aim of this study was to develop and evaluate the psychometric properties of a new measurement tool, the Cancer Functional Assessment Set (cFAS). DESIGN: A total of 119 inpatients with cancer participated in this prospective cohort study. This study took place in three phases: (1) item generation, literature search, and a round-table discussion by 32 rehabilitation specialists; (2) item reduction and selection of appropriate items from the first item pool; and (3) evaluation of psychometric properties. Concurrent validity (Spearman correlation coefficients with existing scales), internal reliability (Cronbach coefficient alpha), interrater reliability (weighted kappa statistics and intraclass correlation coefficient), cross-validation, and responsiveness (standardized response mean values) were examined. RESULTS: The cFAS consisted of 24 items. Significant correlations were found between the cFAS and existing scales. Cronbach α for the total score was 0.92. Weighted κ values for each item ranged from 0.74 to 1.00. The intraclass correlation for the total score was 0.97. Concurrent validity and internal consistency were similar at two different hospitals. The cFAS was more responsive to changes than the other tools. CONCLUSIONS: The cFAS has acceptable psychometric properties, supporting its broad generalizability. It can be a useful tool in clinical trials and can contribute to the development of cancer rehabilitation. Copyright © 2014 Lippincott Williams & Wilkins.

Brain computer interface technology is of great interest to researchers as a potential therapeutic measure for people with severe neurological disorders. The aim of this study was to examine the efficacy of brain computer interface, by comparing conventional neuromuscular electrical stimulation and brain computer interface-driven neuromuscular electrical stimulation, using an A-B-A-B withdrawal single-subject design. A 38-year-old male with severe hemiplegia due to a putaminal haemorrhage participated in this study. The design involved 2 epochs. In epoch A, the patient attempted to open his fingers during the application of neuromuscular electrical stimulation, irrespective of his actual brain activity. In epoch B, neuromuscular electrical stimulation was applied only when a significant motor-related cortical potential was observed in the electroencephalogram. The subject initially showed diffuse functional magnetic resonance imaging activation and small electro-encephalogram responses while attempting finger movement. Epoch A was associated with few neurological or clinical signs of improvement. Epoch B, with a brain computer interface, was associated with marked lateralization of electroencephalogram (EEG) and blood oxygenation level dependent responses. Voluntary electromyogram (EMG) activity, with significant EEG-EMG coherence, was also prompted. Clinical improvement in upper-extremity function and muscle tone was observed. These results indicate that self-directed training with a brain computer interface may induce activity- dependent cortical plasticity and promote functional recovery. This preliminary clinical investigation encourages further research using a controlled design.

Purpose: The purpose was to compare the performance of three representative instruments to measure changes of motor recovery with acute hemispheric stroke. Method: In 41 consecutive patients with acute hemispheric infarction, motor recovery was assessed within 3 days of onset and then every 2 weeks until the 12th week with the Stroke Impairment Assessment Set (SIAS), the National Institutes of Health stroke scale (NIHSS) and the Canadian Neurological Scale (CNS). We analyzed the relationships among the corresponding subscales of the three instruments with the Spearman's rank correlation method, and compared their responsiveness by plotting the temporal profiles of scores of each instrument and by testing the significance of changes over time with the Friedman test. Results: High correlations were observed among the three instruments at each examination point. However, the SIAS scores were more widely dispersed at the same NIHSS and CNS scores. Friedman test revealed that the scores changed significantly during the observation period with the SIAS and the CNS but not with the NIHSS. The changes were detected later with the CNS than with the SIAS. Conclusions: Although the assessment results with the three instruments were highly inter-correlated, the SIAS performed better with respect to responsiveness to changes.Implication for RehabilitationWhen providing rehabilitation services to patients with stroke, it is important to document objectively the level of their impairment from the acute stage and during the entire course of rehabilitation with standardized instrument, and to predict their functional outcomes as early and accurately as possible.This study therefore compared three representative instruments with established psychometric properties, the SIAS, the NIHSS and the CNS, with respect to their ability to document motor impairment and their responsiveness to recovery in patients with acute hemispheric stroke.

Background: Rats exhibit extremely limited motor function recovery after total transection of the spinal cord (SCT). We previously reported that SM-216289, a semaphorin3A inhibitor, enhanced axon regeneration and motor function recovery in SCT adult rats. However, these effects were limited because most regenerated axons likely do not connect to the right targets. Thus, rebuilding the appropriate connections for regenerated axons may enhance recovery. In this study, we combined semaphorin3A inhibitor treatment with extensive treadmill training to determine whether combined treatment would further enhance the "rewiring" of regenerated axons. In this study, which aimed for clinical applicability, we administered a newly developed, potent semaphorin3A inhibitor, SM-345431 (Vinaxanthone), using a novel drug delivery system that enables continuous drug delivery over the period of the experiment. Results: Treatment with SM-345431 using this delivery system enhanced axon regeneration and produced significant, but limited, hindlimb motor function recovery. Although extensive treadmill training combined with SM-345431 administration did not further improve axon regeneration, hindlimb motor performance was restored, as evidenced by the significant improvement in the execution of plantar steps on a treadmill. In contrast, control SCT rats could not execute plantar steps at any point during the experimental period. Further analyses suggested that this strategy reinforced the wiring of central pattern generators in lumbar spinal circuits, which, in turn, led to enhanced motor function recovery (especially in extensor muscles). Conclusions: This study highlights the importance of combining treatments that promote axon regeneration with specific and appropriate rehabilitations that promote rewiring for the treatment of spinal cord injury. © 2014 Zhang et al.; licensee BioMed Central Ltd.

In daily life, we encounter situations where we must quickly decide which hand to use for a motor action. Here, we investigated whether the hand chosen for a motor action varied over a short timescale (i.e., hours) with changes in arm dynamics. Participants performed a reaching task in which they moved a specified hand to reach a target on a virtual reality display. During the task, a resistive viscous force field was abruptly applied to only the dominant hand (DH). To evaluate changes in hand choice caused by this perturbation, participants performed an interleaved choice test in which they could freely choose either hand for reaching. Furthermore, to investigate the effect of temporal changes on arm dynamics and hand choice, we exposed the same participants to another condition in which the force field was introduced gradually. When the abrupt force was applied, use of the perturbed hand significantly decreased and not changed during the training. In contrast, when the incremental force was applied, use of the perturbed hand gradually decreased as force increased. Surprisingly, even though the final amount of force was identical between the two conditions, hand choice was significantly biased toward the unperturbed hand in the gradual condition. These results suggest that time-varying changes in arm dynamics may have a greater influence on hand choice than the amplitude of the resistant force itself. © 2014 Habagishi, Kasuga, Otaka, Liu and Ushiba.