Although motor imagery enhances the excitability of the corticospinal tract, there are no peripheral afferent inputs during motor imagery. In contrast, peripheral nerve electrical stimulation (ES) ...can induce peripheral afferent inputs; thus, a combination of motor imagery and ES may enhance the excitability of the corticospinal tract compared with motor imagery alone. Moreover, the level of stimulation intensity may also be related to the modulation of the excitability of the corticospinal tract during motor imagery. Here, we evaluated whether a combination of motor imagery and peripheral nerve ES influences the excitability of the corticospinal tract and measured the effect of ES intensity on the excitability induced during motor imagery. The imagined task was a movement that involved touching the thumb to the little finger, whereas ES involved simultaneous stimulation of the ulnar and median nerves at the wrist. Two different ES intensities were used, one above the motor threshold and another above the sensory threshold. Further, we evaluated whether actual movement with afferent input induced by ES modulates the excitability of the corticospinal tract as well as motor imagery. We found that a combination of motor imagery and ES enhanced the excitability of the motor cortex in the thenar muscle compared with the other condition. Furthermore, we established that the modulation of the corticospinal tract was related to ES intensity. However, we found that the excitability of the corticospinal tract induced by actual movement was enhanced by peripheral nerve ES above the sensory threshold.
Falls are one of the most common complications of a stroke. This study aimed to clarify the discrepancy between the perceived fall risk of hospitalized patients with stroke and the clinical judgment ...of physical therapists and to examine the changes in discrepancy during hospitalization.
Retrospective cohort study.
This study included 426 patients with stroke admitted to a Japanese convalescent rehabilitation hospital between January 2019 and December 2020.
The Falls Efficacy Scale-International was used to assess both patients' and physical therapists' perception of fall risk. The difference in Falls Efficacy Scale-International scores assessed by patients and physical therapists was defined as the discrepancy in fall risk, and its association with the incidence of falls during hospitalization was investigated.
Patients had a lower perception of fall risk than physical therapists at admission (
< 0.001), and this trend continued at discharge (
< 0.001). The discrepancy in fall risk perception was reduced at discharge for non-fallers and single fallers (
< 0.001), whereas the difference remained in multiple fallers.
Unlike physical therapists, patients underestimated their fall risk, especially patients who experienced multiple falls. These results may be useful for planning measures to prevent falls during hospitalization.
The risk of pneumonia and death is higher in acute stroke patients with signs of pulmonary infection on chest computed tomography (CT) at admission. However, few reports have examined the incidence ...of pneumonia and its predictors in subacute stroke patients. The aim of this study was to examine factors related to post-stroke pneumonia in subacute stroke patients. A total of 340 subacute stroke patients were included. Univariable logistic regression analysis was performed using variables that may contribute to pneumonia, with the development of pneumonia as the dependent variable. Multivariable logistic regression analysis using the three independent variables with the lowest p-values on the univariable logistic regression analysis was also performed to calculate adjusted odds ratios. Twenty-two patients developed pneumonia during hospitalization. The univariable logistic regression analysis showed that the top three items were serum albumin (Alb), functional Oral Intake Scale (FOIS) score, and signs of pulmonary infection on chest CT at admission. Multivariable logistic regression analysis adjusted for these three items showed that the presence of signs of pulmonary infection on chest CT at admission was the independent variable (OR: 4.45; 95% CI: 1.54–12.9). When signs of pulmonary infection are seen on admission chest CT, careful follow-up is necessary because pneumonia is significantly more likely to occur during hospitalization.
•We studied corticospinal excitability during imagined isometric force control tasks.•MEP amplitude during motor imagery is modulated while increasing the imagined force.•Significant modulation was ...confirmed in the agonist muscle after learning.
To investigate real-time excitability changes in corticospinal pathways related to motor imagery in a changing force control task, using transcranial magnetic stimulation (TMS).
Ten healthy volunteers learnt to control the contractile force of isometric right wrist dorsiflexion in order to track an on-screen sine wave form. Participants performed the trained task 40 times with actual muscle contraction in order to construct the motor image. They were then instructed to execute the task without actual muscle contraction, but by imagining contraction of the right wrist in dorsiflexion. Motor evoked potentials (MEPs), induced by TMS in the right extensor carpi radialis muscle (ECR) and flexor carpi radialis muscle (FCR), were measured during motor imagery. MEPs were induced at five time points: prior to imagery, during the gradual generation of the imaged wrist dorsiflexion (Increasing phase), the peak value of the sine wave, during the gradual reduction (Decreasing phase), and after completion of the task. The MEP ratio, as the ratio of imaged MEPs to resting-state, was compared between pre- and post-training at each time point.
In the ECR muscle, the MEP ratio significantly increased during the Increasing phase and at the peak force of dorsiflexion imagery after training. Moreover, the MEP ratio was significantly greater in the Increasing phase than in the Decreasing phase. In the FCR, there were no significant consistent changes.
Corticospinal excitability during motor imagery in an isometric contraction task was modulated in relation to the phase of force control after image construction.
The present paper reports a case with word-meaning deafness who made use of dictation in kana as an alternative means of auditory comprehension. The case was in her fifties, right-handed, and ...diagnosed with Wernickeʼs aphasia due to stroke in the posterior region of the left superior and middle temporal gyri. Although her language impairment was quite improved after three months from the onset, auditory comprehension remained difficult. We examined her process of auditory comprehension in detail and confirmed that she presented typical word-meaning deafness, since her primary difficulty was comprehension of meanings of spoken words ; her capacities of phonological discrimination and auditory lexical decision were almost preserved. In addition, repetition of words and visual comprehension were intact. With respect to processing written words, she presented pure agraphia of kanji but was able to write and comprehended kana words without any problem. This enabled her to make strategic use of kana dictation for comprehending spoken words. The unique point about this caseʼs kana writing is that she was able to write nonwords correctly, unlike other cases of word-meaning deafness. However, on the basis of qualitative analysis, we concluded that she relied on the non-semantic lexical route for kana dictation just as other patients did.
The acquisition of compensatory strategies, such as drawing and gestures, can help people with aphasia when it is difficult to reach a practical level of language function improvement with single ...strategies alone. However, few reports on compensatory strategies specify detailed information on the evaluation criteria for each expression or examine how specific strategies affect daily communication. In this study, we set criteria for the instruction and evaluation of seven people with chronic aphasia, provided staged drawing and gesture training, and examined changes in the outcomes of each strategy and changes in participant motivation and ability to communicate in daily life. The results revealed an immediate improvement in drawing performance compared to that of gestures at the end of the training, and the improved drawing performance was maintained for three months after the training ended. In terms of changes in participant motivation and ability to communicate, there was improved performance of tasks based on daily life situations, and there were many opportunities for the participants to use compensatory strategies in conversation after training. These results suggest that proactive introduction of compensatory strategies improves the motivation and ability of people with aphasia to communicate in daily life.
•Mechanisms of impaired oxygen uptake kinetics in stroke patients were examined.•Oxygen uptake kinetics in patients with stroke may be limited by oxygen delivery.•Poor matching of oxygen delivery and ...uptake was related to functional impairments.
Oxygen uptake (V˙O2) kinetics at the onset of exercise is slower in patients with stroke than in healthy adults. However, little is known about the cardiorespiratory mechanisms underlying the impaired V˙O2 kinetics.
This study aimed to investigate the relative effect of impaired oxygen delivery and utilisation on V˙O2 kinetics at the onset of submaximal exercise in patients with stroke by comparing the time constants of cardiac output (τCO) and V˙O2 (τV˙O2). In addition, we aimed to examine the association between the kinetics of cardiorespiratory variables and functional outcomes.
We included 21 patients with stroke (15 males, mean SD age 58.7 9.5 years, mean days post-stroke 67.9 30.9). A submaximal constant-load exercise test was performed to measure τV˙O2, τCO, and the time constant of arterialvenous oxygen difference (τAVO2diff). The ratio of τCO to τV˙O2 was calculated to assess the matching of oxygen delivery and consumption. Fugl–Meyer lower-extremity motor scores, comfortable gait speeds, and Functional Independence Measure motor scores were used as functional variables.
Mean (SD) τAVO2diff was markedly shorter than τV˙O2 and τCO (26.1 7.1 vs. 38.7 10.2 and 46.6 23.2 s, P<0.05), with no significant difference between τV˙O2 and τCO (P=0.444). The greater ratio of τCO to τV˙O2 was related to poorer motor function (rho=−0.484, P=0.026) and slower comfortable gait speed (r=−0.482, P=0.027).
An increase in CO was slower than that in AVO2diff in patients with stroke. Therefore, V˙O2 kinetics in patients with stroke appears to be affected by a delayed increase in CO rather than AVO2diff. Furthermore, these patients with motor and gait impairments may have a poor matching of oxygen delivery and consumption during exercise onset.
Objective To identify the predictors for the resumption of oral feeding at discharge among tube feeding-dependent stroke patients admitted to rehabilitation wards. Materials and methods This study ...was a retrospective analysis of 107 stroke patients (mean age, 72.1 years) dependent on tube feeds at admission to a rehabilitation ward. Data analyzed included demographic information, severity of impairments, functional independence, body mass index, nutritional and inflammatory laboratory markers at admission, and videofluoroscopic examination findings, if conducted. The variables were compared between the groups with and without resumption of oral intake. The predictive factors for resumption of oral intake were analyzed by using a stepwise multiple logistic regression model. Results At discharge, 69.2% (74 of 107) of the patients resumed oral intake. There were significant differences in age, the Functional Independence Measure, body mass index, serum albumin, C-reactive protein, white blood cell count, and duration of stroke onset at admission between the 2 groups. Multiple logistic regression analysis identified age (odds ratio OR .55; 95% confidence interval CI .31-.95), body mass index (OR 1.34; 95% CI 1.12-1.60), and white blood cell count (OR .76; 95% CI .60-.97) as significant predictors for the resumption of oral intake in these patients. Conclusion Older age, lower body mass index, and higher white blood cell count were significant independent negative predictors for the resumption of oral feeding among stroke patients dependent on tube feeding at admission to rehabilitation wards.
Objective To examine the relationship between the time constant of oxygen uptake kinetics during the onset of exercise (τVO2) estimated from a single exercise bout and that obtained from three ...averaged exercise bouts in individuals with stroke.Methods Twenty participants with stroke performed three bouts of a constant-load pedaling exercise at approximately 80% of the workload corresponding to the ventilatory threshold to estimate τVO2. The VO2 data from the first trial of three bouts were used to estimate τVO2 for a single bout. Additionally, data collected from three bouts were ensemble-averaged to obtain τVO2 for three averaged bouts as the criterion.Results There was a very high correlation between τVO2 for a single bout (34.8±14.0 seconds) and τVO2 for three averaged bouts (38.5±13.4 seconds) (r=0.926, p<0.001). However, τVO2 for a single bout was smaller than that for three averaged bouts (p=0.006).Conclusion τVO2 for a single bout could reflect the relative difference in τVO2 for three averaged bouts among individuals with stroke. However, it should be noted that τVO2 for a single bout may be underestimated compared to τVO2 for three averaged bouts.
PDF
