Published papers

© 2017 Informa UK Limited, trading as Taylor & Francis Group. Purpose: Swallowing dysfunction has been reported in Duchenne muscular dystrophy (DMD), but has not been studied in Becker muscular dystrophy (BMD). The aims of this study were to report the characteristics of swallowing dysfunction in BMD compared with DMD. Materials and methods: The study participants were 18 patients with BMD and 18 patients with DMD. All the patients were examined using videofluorography during swallowing of 5 mL of fluid. The penetration–aspiration scale (P–A scale) and the videofluorographic dysphagia scale (VDS) were used to evaluate dysphagia. Results: Swinyard functional ability stage was not significantly different between the BMD and DMD groups. Rate of aspiration, P–A scale score, and total VDS score did not differ across groups, but the VDS item score for laryngeal elevation was lower in the BMD group than in the DMD group (median scores 4.5 and 9, respectively; p < 0.001). In the BMD group, total VDS score significantly correlated with Swinyard stage (r = 0.78, p < 0.001), but not with age or lung function. Conclusion: Patients with BMD have swallowing problems similar to those observed in patients with DMD when matched according to physical functional status. These patients should be evaluated and followed-up for the duration of their disease. Implications for rehabiliation Dysphagia is one of the most critical problems in patients with progressive neuromuscular disease but dysphagia in patients with Becker muscular dystrophy (BMD) was not well known. Eighteen patients with BMD and 18 patients with Duchenne muscular dystrophy were examined with videofluorography. Patients with BMD have swallowing problems similar to those observed in patients with DMD.

© 2018 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals, Inc on behalf of American Neurological Association. Brain-computer interfaces (BCIs) can provide sensory feedback of ongoing brain oscillations, enabling stroke survivors to modulate their sensorimotor rhythms purposefully. A number of recent clinical studies indicate that repeated use of such BCIs might trigger neurological recovery and hence improvement in motor function. Here, we provide a first meta-analysis evaluating the clinical effectiveness of BCI-based post-stroke motor rehabilitation. Trials were identified using MEDLINE, CENTRAL, PEDro and by inspection of references in several review articles. We selected randomized controlled trials that used BCIs for post-stroke motor rehabilitation and provided motor impairment scores before and after the intervention. A random-effects inverse variance method was used to calculate the summary effect size. We initially identified 524 articles and, after removing duplicates, we screened titles and abstracts of 473 articles. We found 26 articles corresponding to BCI clinical trials, of these, there were nine studies that involved a total of 235 post-stroke survivors that fulfilled the inclusion criterion (randomized controlled trials that examined motor performance as an outcome measure) for the meta-analysis. Motor improvements, mostly quantified by the upper limb Fugl-Meyer Assessment (FMA-UE), exceeded the minimal clinically important difference (MCID=5.25) in six BCI studies, while such improvement was reached only in three control groups. Overall, the BCI training was associated with a standardized mean difference of 0.79 (95% CI: 0.37 to 1.20) in FMA-UE compared to control conditions, which is in the range of medium to large summary effect size. In addition, several studies indicated BCI-induced functional and structural neuroplasticity at a subclinical level. This suggests that BCI technology could be an effective intervention for post-stroke upper limb rehabilitation. However, more studies with larger sample size are required to increase the reliability of these results.

© 2018 Michiyuki Kawakami et al. We investigated cortically mediated changes in reciprocal inhibition (RI) following motor imagery (MI) in short- and long(er)-term periods. The goals of this study were (1) to describe RI during MI in patients with chronic stroke and (2) to examine the change in RI after MI-based brain-machine interface (BMI) training. Twenty-four chronic stroke patients participated in study 1. All patients imagined wrist extension on the affected side. RI from the extensor carpi radialis to the flexor carpi radialis (FCR) was assessed using a FCR H reflex conditioning-test paradigm. We calculated the "MI effect score on RI" (RI value during MI divided by that at rest) and compared that score according to lesion location. RI during MI showed a significant enhancement compared with RI at rest. The MI effect score on RI in the subcortical lesion group was significantly greater than that in the cortical lesion group. Eleven stroke patients participated in study 2. All patients performed BMI training for 10 days. The MI effect score on RI at a 20 ms interstimulus interval was significantly increased after BMI compared with baseline. In conclusion, mental practice with MI may induce plastic change in spinal reciprocal inhibitory circuits in patients with stroke.

© 2019 The Authors It has been reported that it is possible to observe transient changes in resting-state functional connectivity (FC) in the attention networks of healthy adults during treatment with prism adaptation. by using functional magnetic resonance imaging (fMRI) (see “Prism adaptation changes resting-state functional connectivity in the dorsal stream of visual attention networks in healthy adults: A fMRI study” (Tsujimoto et al., 2018) [1]. Recent neuroimaging and neurophysiological studies support the idea that prism adaptation (PA) affects the visual attention and sensorimotor networks, which include the parietal cortex and cerebellum. These data demonstrate the effect of PA on resting-state functional connectivity between the primary motor cortex and cerebellum. Additionally, it evaluates changes of resting-state FC before and after PA in healthy individuals using fMRI. Analyses focus on FC between the primary motor cortex and cerebellum, and the correlation between changes in FC and its after-effects following a single PA session. Here, we show data that demonstrate the change in resting-state FC between the primary motor cortex and cerebellum, as well as a correlation between the change ratio of FC and the amplitude of the after-effect.

© 2018 IEEE. There have been recent advances in brain-computer interfaces for post-stroke rehabilitation. In particular, compact and embedded brain-computer interface systems with neuromuscular electrical stimulation have been developed by industry and academia, and some of them can potentially be used at the bedside. However, limited studies have demonstrated their safety and feasibility for treatment in subacute stroke patients. The aim of this pilot study was to first develop a brain-computer interface system for subacute stroke inpatients that is usable at the bedside and to show the safety and feasibility using a small cohort of inpatients. Four hemiplegic stroke inpatients in the very early phase (7-24 days from stroke onset) participated in this study. The portable brain-computer interface system shows the amplitude of sensorimotor rhythms extracted from scalp electroencephalograms in real time. Patients attempted to extend the wrist on their affected side, and neuromuscular electrical stimulation was applied only when the brain-computer interface system detected significant movement intention-related electroencephalogram changes. Each brain-computer interface training lasted 40 minutes. On average, 120-200 training trials of the wrist extension task were successfully and safely conducted over 3.3 days (range 2-4 days) with the bedside brain-computer interface system. Furthermore, electroencephalogram results showed a new significant event-related desynchronization in the damaged hemisphere after training. These results clearly show the proposed bedside brain-computer interface system's safety and feasibility and also demonstrated electrophysiological plasticity in the damaged hemisphere in subacute patients with post-stroke hemiplegia. Larger clinical studies are needed to identify the brain-computer interface system's clinical efficacy and its effect size in the subacute post-stroke patient population.

© 2018 IEEE. Since exoskeletons show potential for rehabilitation therapy, many scientists have been designing upper extremity exoskeletons. Unfortunately, few have successfully provided a shoulder exoskeleton for severe impairment. Toward Brain-Machine-Interface (BMI) rehabilitation robot therapies for severe upper extremity impairment, this paper introduces a shoulder exoskeleton robot with a modular joint and an off-board modular actuator. We applied a Modular Exoskeletal Joint (MEJ) to a shoulder exoskeleton that was driven by Pneumatic Artificial Muscles (PAMs) transmitted by a Bowden cable. Our objective is generating passive movements triggered by BMI. Since large torque has to be generated for assist a whole arm, we newly designed a more powerful Nested-cylinder PAMs (NcPAMs) than our previous work. As a proof of the concept of the mechatronics design, we show the tracking performance of the periodic trajectory of a joint angle with both human and mannequin arms as simulated impairments. Our result shows that the tracking error is sufficiently small in all of the conditions and that our developed shoulder exoskeleton is an adequate substitute for flexion/extension movements.

© The Author(s), 2018. Background: The combination of motor imagery (MI) and afferent input with electrical stimulation (ES) enhances the excitability of the corticospinal tract compared with motor imagery alone or electrical stimulation alone. However, its therapeutic effect is unknown in patients with hemiparetic stroke. We performed a preliminary examination of the therapeutic effects of MI + ES on upper extremity (UE) motor function in patients with chronic stroke. Methods: A total of 10 patients with chronic stroke demonstrating severe hemiparesis participated. The imagined task was extension of the affected finger. Peripheral nerve electrical stimulation was applied to the radial nerve at the spiral groove. MI + ES intervention was conducted for 10 days. UE motor function as assessed with the Fugl–Meyer assessment UE motor score (FMA-UE), the amount of the affected UE use in daily life as assessed with a Motor Activity Log (MAL-AOU), and the degree of hypertonia in flexor muscles as assessed with the Modified Ashworth Scale (MAS) were evaluated before and after intervention. To assess the change in spinal neural circuits, reciprocal inhibition between forearm extensor and flexor muscles with the H reflex conditioning-test paradigm at interstimulus intervals (ISIs) of 0, 20, and 100 ms were measured before and after intervention. Results: UE motor function, the amount of the affected UE use, and muscle hypertonia in flexor muscles were significantly improved after MI + ES intervention (FMA-UE: p < 0.01, MAL-AOU: p < 0.01, MAS: p = 0.02). Neurophysiologically, the intervention induced restoration of reciprocal inhibition from the forearm extensor to the flexor muscles (ISI at 0 ms: p = 0.03, ISI at 20 ms: p = 0.03, ISI at 100 ms: p = 0.01). Conclusion: MI + ES intervention was effective for improving UE motor function in patients with severe paralysis.

© 2018 Foundation of Rehabilitation Information. Objective: Brain-machine interface training was developed for upper-extremity rehabilitation for patients with severe hemiparesis. Its clinical application, however, has been limited because of its lack of feasibility in real-world rehabilitation settings. We developed a new compact task-specific brain-machine interface system that enables task-specific training, including reach-and-grasp tasks, and studied its clinical feasibility and effectiveness for upper-extremity motor paralysis in patients with stroke. Design: Prospective before-after study. Subjects: Twenty-six patients with severe chronic hemiparetic stroke. Methods: Participants were trained with the brainmachine interface system to pick up and release pegs during 40-min sessions and 40 min of standard occupational therapy per day for 10 days. Fugl-Meyer upper-extremity motor (FMA) and Motor Activity Log-14 amount of use (MAL-AOU) scores were assessed before and after the intervention. To test its feasibility, 4 occupational therapists who operated the system for the first time assessed it with the Quebec User Evaluation of Satisfaction with assistive Technology (QUEST) 2.0. Results: FMA and MAL-AOU scores improved significantly after brain-machine interface training, with the effect sizes being medium and large, respectively (p < 0.01, d = 0.55; p < 0.01, d = 0.88). QUEST effectiveness and safety scores showed feasibility and satisfaction in the clinical setting. Conclusion: Our newly developed compact brainmachine interface system is feasible for use in realworld clinical settings.

© 2018 European Paediatric Neurology Society Background: Dysphagia is a well-known dysfunction in patients with Duchenne muscular dystrophy (DMD), but long-term follow-up of this symptom has not been reported. The aims of this study were to investigate swallowing status, prospectively study the prognosis of swallowing function in adult patients with DMD over the course of 6 years, and to identify clinical factors related to prognosis. Methods: Participants were 81 patients with DMD. Swallowing status was assessed using the Neuromuscular Disease Swallowing Status Scale (NdSSS) every 2 years for 6 years. Results: NdSSS was related to age, functional ability assessed using the Swinyard staging and the status of ventilator dependence. Median NdSSS changed from 6 to 4, 4 and 3 over the 4 time points. Number of patients with tube feeding increased by 5–10% every 2 years. Initial NdSSS was a predictor of future swallowing status. Conclusion: Swallowing status declined over time in patients with adult DMD, with initial NdSSS as a predictor.

© 2018 Japan Geriatrics Society Aim: Pneumonia is a common disease that is often fatal, particularly in older persons. Dysphagia is known to be closely associated with aspiration pneumonia, and hospitalized patients with aspiration pneumonia often have difficulty with oral intake. However, the relationship between acquisition of oral intake and detailed swallowing data has not been explored. The purpose of the present study was to examine the predictors, including videofluoroscopic swallowing evaluation, for achieving oral intake in older patients with aspiration pneumonia. Methods: This study included older patients, aged ≥65 years, who were admitted to Kawasaki Municipal Hospital (Kawasaki, Japan) from April 2012 through March 2014 as a result of aspiration pneumonia. Factors likely related to oral intake, including swallowing, nutritional, metabolic, and functional status, pneumonia severity and comorbidities were extracted from the medical records. Multiple logistic regression analysis was carried out to identify independent predictors for acquisition of oral intake. Results: A total of 160 patients were assigned to either the “oral intake” group (n = 104) or the “non-oral intake” group (n = 56). Multiple regression analysis showed that a low penetration aspiration scale on videofluoroscopy using 3 mL of moderately thick liquid water with tilting 30–60°, high albumin values, short duration of non-oral intake and a high Food Intake Level Scale score before admission were significantly associated with achievement of oral intake. Conclusions: Aspiration on videofluoroscopy, swallowing status before admission, nutritional status and duration of non-oral intake are important factors for acquiring oral intake. These results might be helpful for the management of older patients with aspiration pneumonia. Geriatr Gerontol Int 2018; 18: 1469–1473.

© 2018 Yamaguchi, Fujiwara, Lin, Takahashi, Hatori, Liu and Huang. This study explored the effect of corticospinal activity on spinal plasticity by examining the interactions between intermittent theta burst transcranial magnetic stimulation (iTBS) of the motor cortex and peripheral patterned electrical stimulation (PES) of the common peroneal nerve (CPN). Healthy volunteers (n = 10) received iTBS to the tibialis anterior (TA) muscle zone of the motor cortex and PES of the CPN in three separate sessions: (1) iTBS-before-PES, (2) iTBS-after-PES, and (3) sham iTBS-before-PES. The PES protocol used 10 100-Hz pulses every 2 s for 20 min. Reciprocal inhibition (RI) from the TA to soleus muscle and motor cortical excitability of the TA and soleus muscles were assessed at baseline, before PES, and 0, 15, 30, and 45 min after PES. When compared to the other protocols, iTBS-before-PES significantly increased changes in disynaptic RI for 15 min and altered long-loop presynaptic inhibition immediately after PES. Moreover, the iTBS-induced cortical excitability changes in the TA before PES were correlated with the enhancement of disynaptic RI immediately after PES. These results demonstrate that spinal plasticity can be modified by altering cortical excitability. This study provides insight into the interactions between modulation of corticospinal excitability and spinal RI, which may help in developing new rehabilitation strategies.

© 2018 Foundation of Rehabilitation Information. Objective: To examine the left ventricular ejection fraction in patients with subacute stroke and compare rehabilitation outcomes between those with decreased left ventricular ejection fraction and those without. Design: Retrospective chart review. Subjects: A total of 482 consecutive patients with stroke admitted to a convalescent rehabilitation hospital. Methods: Patients were assessed using transthoracic echocardiography within 7 days of admission. The patients were divided into a group with low left ventricular ejection fraction and a group with preserved left ventricular ejection fraction. Functional Independence Measure (FIM) scores at admission and discharge, FIM gain, FIM efficiency, and discharge disposition were compared between groups. Results: The low left ventricular ejection fraction group had significantly lower cognitive and total FIM scores on admission than the preserved left ventricular ejection fraction group. The patients in the low left ventricular ejection fraction group tended to be transferred to acute hospitals more frequently. However, the total score of discharge FIM, FIM gain, and FIM efficiency did not differ significantly between the groups when rehabilitation was continued until discharge. Conclusion: Stroke patients with low left ventricular ejection fraction in the subacute phase could achieve almost the same functional outcomes as those of patients with preserved left ventricular ejection fraction. Although the general medical condition should be considered, the finding of low left ventricular ejection fraction did not pose a barrier to successful rehabilitation after stroke.

© 2017, Springer-Verlag GmbH Germany, part of Springer Nature. Spasticity is a common problem in patients with stroke that contributes to motor dysfunction. However, the pathophysiological mechanisms underlying spasticity are not fully understood. The purpose of the present study was to explain the relationship between features of spinal neural circuits assessed using electrophysiological techniques and the clinical manifestations of stroke. The participants were 71 patients with chronic hemiparetic stroke. To assess spinal neural circuits, Hmax/Mmax of the forearm flexor muscles and reciprocal inhibition (RI) between forearm extensor and flexor muscles with the H reflex conditioning-test paradigm were measured. The relationships between electrophysiological parameters and clinical variables (age, time from stroke onset, upper extremity functional scores, and spasticity) were then analyzed. It was found that the third phase of RI (RI-3) correlated with the modified Ashworth scores of the wrist and finger flexors. No other correlations were found between electrophysiological and clinical measures. These results suggest that RI-3 is associated with spasticity and may be helpful to understand the basis of post-stroke spasticity.

© 2018 Kodama, Ono, Yamashita, Ebata, Liu, Kasuga and Ushiba. Recent studies have revealed rapid (e.g., hours to days) training-induced cortical structural changes using magnetic resonance imaging (MRI). Currently, there is great interest in studying how such a rapid brain structural change affects behavioral improvement. Structural reorganization contributes to memory or enhanced information processing in the brain and may increase its capability of skill learning. If the gray matter (GM) is capable of such rapid structural reorganization upon training, the extent of volume increase may characterize the learning process. To shed light on this issue, we conducted a case series study of 5-day visuomotor learning using neuroanatomical imaging, and analyzed the effect of rapid brain structural change on motor performance improvement via regression analysis. Participants performed an upper-arm reaching task under left-right mirror-reversal for five consecutive days; T1-weighted MR imaging was performed before training, after the first and fifth days, and 1 week and 1 month after training. We detected increase in GM volume on the first day (i.e., a few hours after the first training session) in the primary motor cortex (M1), primary sensory cortex (S1), and in the hippocampal areas. Notably, regression analysis revealed that individual differences in such short-term increases were associated with the learning levels after 5 days of training. These results suggest that GM structural changes are not simply a footprint of previous motor learning but have some relationship with future motor learning. In conclusion, the present study provides new insight into the role of structural changes in causing functional changes during motor learning.

© Copyright 2018, Mary Ann Liebert, Inc., publishers 2018. Progress in regenerative medicine is realizing the possibility of neural regeneration and functional recovery in spinal cord injury (SCI). Recently, rehabilitation has attracted much attention with respect to the synergistic promotion of functional recovery in combination with neural stem/progenitor cell (NS/PC) transplantation, even in the chronic refractory phase of SCI. Nevertheless, sensory disturbance is one of the most prominent sequelae, even though the effects of combination or single therapies have been investigated mostly in the context of motor recovery. To determine how combination therapy with treadmill training (TMT) and NS/PC transplantation affects the manifestation of thermal allodynia and tactile hyperalgesia in chronic phase SCI, four groups of SCI mice were used to assess pain-related behavior and histological changes: combined transplantation and TMT therapy, transplantation only, TMT only, and control groups. Thermal allodynia and coarse touch-pressure hyperalgesia exhibited significant recovery in the combined therapy group in comparison with controls, whereas there were no significant differences with fine touch-pressure hyperalgesia and motor function. Further investigation revealed fewer fibers remaining in the posterior funiculus, which contained the tracts associated with the two modalities showing less recovery; that is, touch-pressure hyperalgesia and motor function. A significant correlation was only observed between these two modalities. Although no remarkable histological recovery was found within the lesion epicenter, changes indicating amelioration of pain were observed in the lumbar enlargement of the combination therapy group. Our results suggest that amelioration of thermal allodynia and tactile hyperalgesia can be brought about by the additive effect of NS/PC transplantation and TMT. The degree of recovery seems dependent on the distribution of damage.

© 2016-IOS Press and the authors. All rights reserved. Background: Reciprocal inhibition (RI) may be important for recovering locomotion after stroke. Patterned electrical stimulation (PES) can modulate RI in a manner that could be enhanced by voluntary muscle contraction (VC). Objective: To investigate whether VC enhances the PES-induced spinal RI in patients with stroke. Methods: Twelve patients with chronic stroke underwent three 20 min tasks, each on different days: (1) PES (10 pulses, 100 Hz every 2 s) applied to the common peroneal nerve; (2) VC consisting of isometric contraction of the affected-side tibialis anterior muscle; (3) PES combined with VC (PES + VC). RI from the tibialis anterior to the soleus muscle was assessed before, immediately after, and 10, 20, and 30 min after the task. Results: Compared to the baseline, PES + VC significantly increased the changes in reciprocal inhibition at immediately after and 10 min after the task. PES alone significantly increased this change immediately after the task, while VC alone showed no significant increase. Conclusion: VC enhanced the PES-induced plastic changes in RI in patients with stroke. This effect can potentially increase the success rate of newer neurorehabilitative approaches in achieving functional recovery after stroke.

Amplitudes of mu and beta (7-26. Hz) oscillations measured by electroencephalography over the sensorimotor areas are suppressed during motor imagery as well as during voluntary movements. This phenomenon is referred to as event-related desynchronization (ERD) and is known to reflect motor cortical excitability. The increased motor cortical excitability associated with ERD during hand motor imagery would induce a descending cortical volley to spinal motoneurons, resulting in facilitation of spinal motoneuronal excitability. Therefore, in the present study, we tested the association of ERD during motor imagery with the excitability of spinal motoneurons in 15 healthy participants. Spinal excitability was tested using the F-wave recorded from the right abductor pollicis brevis muscle. The F-wave results from antidromic activation of spinal motoneurons and is induced by peripheral nerve stimulation. Participants performed 5. s of motor imagery of right thumb abduction following 7. s of rest. The right median nerve was stimulated at wrist level when the ERD magnitude of the contralateral hand sensorimotor area exceeded predetermined thresholds during motor imagery. The results showed ERD magnitude during hand motor imagery was associated with an increase in F-wave persistence, but not with the response average of F-wave amplitude or F-wave latency. These findings suggest that the ERD magnitude may be a biomarker representing increases in the excitability of both cortical and spinal levels.

Objective: The simple test for evaluating hand function (STEF) is widely used for clinical evaluation of upper extremity function in Japan. However, except for test-re-test reliability, its psychometric properties have not been investigated. The aim of this study is to explore its internal consistency, concurrent validity and responsiveness in patients with sub-acute stroke. Design: This was a prospective longitudinal study. Patients: Thirty-four inpatients who had suffered hemiparetic stroke within 60 days of participation were enrolled. Methods: To investigate its internal consistency and responsiveness, they were assessed with the STEF and Action Research Arm Test (ARAT) at admission and 3 weeks later. To explore its concurrent validity, the Fugl-Meyer Assessment (FMA), Motor Activity Log (MAL) and Functional Independence Measure (FIM™) were also evaluated at admission. Results: The Cronbach's alpha for the STEF was 0.98-0.99, indicating excellent internal consistency. The STEF score strongly correlated with the ARAT, FMA and MAL scores and moderately with the FIM™ score. Effect sizes and the standardized response mean were 0.27 and 0.52 for the STEF and 0.30 and 0.95 for the ARAT, respectively. Conclusion: This study indicates that the STEF is reliable, valid and sensitive to changes when applied to patients with sub-acute stroke.

Background: The energy demands in patients with stroke during the subacute phases are unclear. However, this information is essential for appropriate clinical and nutritional management. The aims of this study were to determine the resting energy expenditure (REE) during the subacute phases, examine its relationships with stroke types, location, severity of hemiparesis, and activities of daily living (ADL), and evaluate whether estimation of REE from the Harris-Benedict equation (HB) requires the addition of a 'stress factor' to capture possible additional REE imposed by stroke. Methods: We measured REE in 95 patients with subacute stroke (53.5 ± 16.6 days post-stroke) with indirect calorimetry, and compared it with predicted values of energy expenditure estimated from the HB (expressed as percentage). Patients were admitted for rehabilitation of their first ischemic or nonsurgical hemorrhagic stroke. The severity of hemiparesis was assessed with the motor items of the Stroke Impairment Assessment Set (SIAS). The ADL was assessed with the Functional Independence Measure (FIM). We compared REE and %HB of the two groups divided by hemiparesis severity and ADL limitation using the Student's t-test, and those of the five groups divided by stroke location. The correlations between REE and the motor items of the SIAS and the FIM score were assessed with the Spearman rank correlation test. A multiple regression analysis for REE was conducted. Results: The average body weight (BW) was 57.1 ± 11.3 kg. The average body mass index (BMI) was 22.5 ± 4.0. The mean REE (%HB) was 1,271 ± 284 kcal/day (106.0 ± 17.3%). REE and %HB of the low ADL group was less than that of the high ADL group (p < 0.05). The REE had a positive correlation with the FIM score (rs = 0.51, p < 0.01). The motor items of the SIAS were not significantly correlated with REE. BW, FIM, and stroke location were independent predictors of REE. Conclusions: Analysis of energy expenditure suggests that stroke patients are not hypermetabolic during the subacute phase. The 'stress factor' in stroke patients during the subacute phase was 1.0-1.1. This finding provides important information for improving nutritional management during the subacute phase in patients with stroke.

Human's sophisticated motor learning system paradoxically interferes with motor performance when visual information is mirror-reversed (MR), because normal movement error correction further aggravates the error. This error-increasing mechanism makes performing even a simple reaching task difficult, but is overcome by alterations in the error correction rule during the trials. To isolate factors that trigger learners to change the error correction rule, we manipulated the gain of visual angular errors when participants made arm-reaching movements with mirror-reversed visual feedback, and compared the rule alteration timing between groups with normal or reduced gain. Trial-by-trial changes in the visual angular error was tracked to explain the timing of the change in the error correction rule. Under both gain conditions, visual angular errors increased under the MR transformation, and suddenly decreased after 3-5 trials with increase. The increase became degressive at different amplitude between the two groups, nearly proportional to the visual gain. The findings suggest that the alteration of the error-correction rule is not dependent on the amplitude of visual angular errors, and possibly determined by the number of trials over which the errors increased or statistical property of the environment. The current results encourage future intensive studies focusing on the exact rule-change mechanism.