Effects of rTMS to primary motor cortex and cerebellum on balance control in healthy adults.

Both the primary motor cortex (M1) and the cerebellum are crucial for postural stability and deemed as potential targets for non-invasive brain stimulation (NIBS) to enhance balance performance. However, the optimal target remains unknown. The purpose of this study was to compare the role of M1 and the cerebellum in modulating balance performance in young healthy adults using facilitatory 5 Hz repetitive transcranial magnetic stimulation (rTMS). Twenty-one healthy young adults (mean age = 27.95 ± 1.15 years) received a single session of 5 Hz rTMS on M1 and the cerebellum in a cross-over order with a 7-day washout period between the two sessions. Three balance assessments were performed on the Biodex Balance system SD: Limits of Stability (LOS), modified Clinical Test of Sensory Interaction on Balance (mCTSIB), and Balance Error Scoring System (BESS). No significant effect of rTMS was found on the LOS. The effect of rTMS on the mCTSIB was mediated by stimulation target, proprioception, and vision (p = .003, ηp 2 = 0.37). Cerebellar rTMS improved the mCTSIB sway index under eyes closed-foam surface condition (p = .02), whereas M1 rTMS did not result in improvement on the mCTSIB. The effect of rTMS on the BESS was mediated by stimulation target, posture, and proprioception (p = .049, ηp 2 = 0.14). Cerebellar rTMS enhanced reactive balance performance during most sensory deprived conditions.

Fatigue Is Associated With Perceived Effort and 2-Dimensional Reach Performance After Stroke.

BACKGROUND AND PURPOSE: Poststroke fatigue (PSF) is prevalent and often manifests as high perceived effort during activities. Little is known about how PSF influences goal-directed reaching after stroke. The purpose of this study was 2-fold (1) to evaluate how perceived effort changed when individuals with stroke performed a reaching task with various demands and (2) to determine whether PSF was associated with perceived effort during reaching and reach performance. METHODS: Thirty-six individuals with chronic stroke performed 2-dimensional reach actions under varied conditions with the more and less affected arms. Perceived effort during reaching was assessed using rating of perceived exertion (RPE) and Paas Mental Effort Rating Scale (MERS). Derived reach kinematics were used to quantify reach performance. The Fatigue Severity Scale (FSS) was administered to assess fatigue severity. RESULTS: Perceived effort was higher when participants reached with the more affected arm, reached toward far and small targets, and performed memory-guided reaching. Both RPE and MERS significantly correlated with the FSS score (r = 0.50 and 0.35, respectively, P < 0.05). Further, FSS correlated with movement time during the more affected arm reaching (ρ = 0.40, p < 0.05) and reach performance discrepancy between the fast and self-selected speed conditions when participants performed with the less affected arm (ρ = 0.36, P < 0.05). Exploratory analysis revealed that the relationship between fatigue and reach control appeared to be modulated by task demand. DISCUSSION AND CONCLUSIONS: PSF is associated with perceived effort during reaching and reach performance after stroke. These relationships might offer insights into arm performance in the real world after stroke. VIDEO ABSTRACT: for more insights from the authors Supplemental Digital Content available at http://links.lww.com/JNPT/A476.

Task matters: an investigation on the effect of different secondary tasks on dual-task gait in older adults.

BACKGROUND: Dual-task gait performance declines as humans age, leading to increased fall risk among older adults. It is unclear whether different secondary cognitive tasks mediate age-related decline in dual-task gait. This study aimed to examine how type and difficulty level of the secondary cognitive tasks differentially affect dual-task gait in older adults. METHODS: Twenty young and twenty older adults participated in this single-session study. We employed four different types of secondary tasks and each consisted of two difficulty levels, yielding eight different dual-task conditions. The dual-task conditions included walking and 1) counting backward by 3 s or by 7 s; 2) remembering a 5-item or 7-item lists; 3) responding to a simple or choice reaction time tasks; 4) generating words from single or alternated categories. Gait speed and cognitive task performance under single- and dual-task conditions were used to compute dual-task cost (DTC, %) with a greater DTC indicating a worse performance. RESULTS: A significant three-way interaction was found for the gait speed DTC (p = .04). Increased difficulty in the reaction time task significantly increased gait speed DTC for older adults (p = .01) but not for young adults (p = .90). In contrast, increased difficulty level in the counting backward task significantly increased gait speed DTC for young adults (p = .03) but not for older adults (p = .85). Both groups responded similarly to the increased task difficulty in the other two tasks. CONCLUSIONS: Older adults demonstrated a different response to dual-task challenges than young adults. Aging might have different impacts on various cognitive domains and result in distinctive dual-task gait interference patterns.

Poststroke Fatigue Is Related to Motor and Cognitive Performance: A Secondary Analysis.

BACKGROUND AND PURPOSE: Poststroke fatigue (PSF) is a common debilitating and persistent symptom after stroke. The relationship between PSF and motor and cognitive function remains inconclusive partly due to lack of control for effects of depression and use of insensitive measures. We examined the relationship between PSF and motor and cognitive performance using a comprehensive set of behavioral measures and excluding individuals with depression. METHODS: Fifty-three individuals poststroke (16 female) were included (median age: 63 years, median months poststroke: 20 months). Poststroke fatigue was quantified using the Fatigue Severity Scale (FSS) and cognitive performance was measured with the Montreal Cognitive Assessment, simple and choice reaction time (SRT and CRT) tasks. Lower extremity motor performance included Fugl-Meyer Motor Assessment, 5 times sit-to-stand test (5 × STS), Berg Balance Scale, Functional Ambulation Category, and gait speed. Upper extremity motor performance was indexed with Fugl-Meyer, grip strength, and Box and Block test. Spearman correlation and stepwise linear regression analyses were performed to examine relationships. RESULTS: Two motor performance measures, Berg Balance Scale and Functional Ambulation Category, were significantly correlated with FSS (ρ = -0.31 and -0.27, respectively) while all cognitive measures were significantly correlated with FSS (ρ = -0.28 for Montreal Cognitive Assessment, 0.29 for SRT, and 0.29 for CRT). Regression analysis showed that Berg Balance Scale was the only significant determinant for FSS (R = 0.11). DISCUSSION AND CONCLUSIONS: Functional gait, balance, and cognitive performance are associated with PSF. Fatigue should be considered when planning and delivering interventions for individuals with stroke. Future studies are needed to explore the potential efficacy of balance and cognitive training in PSF management.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A287).

Aftereffects of 2 noninvasive brain stimulation techniques on corticospinal excitability in persons with chronic stroke: a pilot study.

BACKGROUND AND PURPOSE: Noninvasive brain stimulation, including repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), have gained popularity in the stroke rehabilitation literature. Little is known about the time course and duration of effects of noninvasive brain stimulation on corticospinal excitability in individuals with stroke. We examined the aftereffects of a single session of high-frequency rTMS (5 Hz) and anodal tDCS on corticospinal excitability in the same sample of participants with chronic stroke. METHODS: Ten individuals with chronic stroke participated in this randomized cross-over study. Participants received 1 session of rTMS and 1 session of tDCS, with 1 week between sessions. During the rTMS session, 5-Hz rTMS (total of 1200 stimuli) was administered to the ipsilesional primary motor cortex (M1). For anodal tDCS, 1 mA of direct current was delivered to the ipsilesional M1 for 20 minutes. Motor evoked potentials were measured before and after (immediately, 15 minutes, 30 minutes, and 60 minutes) each stimulation session. RESULTS: Both 5-Hz rTMS and anodal tDCS significantly increased corticospinal excitability for 30 to 60 minutes after stimulation. There was no statistically significant difference between the 2 stimulation techniques in their effects on motor evoked potentials. No changes in measures of motor or cognitive performance were observed. DISCUSSION AND CONCLUSION: Both 5-Hz rTMS and anodal tDCS induced effects on corticospinal excitability in persons with chronic stroke lasting at least 1 hour after stimulation. In the absence of concurrent motor practice, neither form of stimulation applied in a single session was associated the changes in motor performance. These approaches to increased cortical excitability may be of value as adjuncts to training. VIDEO ABSTRACT AVAILABLE: See Video (Supplemental Digital Content 1, http://links.lww.com/JNPT/A83) for more insights from the authors.

Post-stroke fatigue: a review on prevalence, correlates, measurement, and management.

BACKGROUND: Post-stroke fatigue (PSF) is a common yet debilitating symptom for the majority of patients post-stroke. However, limited information is available for the management of this disabling condition. This is partly due to our poor understanding of the condition. OBJECTIVES: In this paper, we review the prevalence, predisposing factors, impact, measurement, and management of PSF. RESULTS: The prevalence of PSF ranged from 29 to 70%, depending on the selected outcome measurement tools and the patient characteristics. Predisposing factors of PSF are multifactorial, including biological, physical, and psychological factors. Further, the relationships between some of the predisposing factors and PSF seem to be indirect. CONCLUSIONS: PSF has an adverse effect on the patient's quality of life, recovery, and mortality. Its impact on physical function and independence requires further investigation. There are a number of tools available to measure fatigue in neurological conditions. However, very few of them have been validated in stroke. Lastly, single-disciplinary management for PSF was rarely successful. In contrast, evidence suggests that approaches which incorporated both physical and psychological interventions may be beneficial. Further studies are urgently needed to gain a better understanding of the etiology of PSF, such that the development of better management strategies is possible.

Motor learning in children with hemiplegic cerebral palsy: feedback effects on skill acquisition.

AIM: Motor learning is enhanced with practice and feedback. This cohort control study investigated the effect of different relative feedback frequencies during skill acquisition in children with cerebral palsy (CP) and children with typical development. METHOD: Nineteen children with spastic hemiplegic CP (nine males, 10 females; mean age 11 y 7 mo; range 8-16 y) and 20 children with typical development (12 males, eight females; mean age 10 y 8 mo; range 8-14 y) were assigned to 100% or reduced (62%) feedback subgroups as they practised 200 trials of a discrete arm movement with specific spatiotemporal parameters. Children with CP used their less involved hand. Learning was inferred by delayed (24 h) retention and reacquisition tests. RESULTS: All children improved in accuracy and consistency. Children with typical development demonstrated significantly greater accuracy than children with CP during acquisition (p=0.001), retention (p=0.031), and reacquisition (p=0.001), and greater consistency during retention (p=0.038). The typically developing group who received 100% feedback performed with significantly less error than the 62% feedback group during acquisition (p=0.001), and with greater retention (p=0.017). No statistically significant difference was found between feedback subgroups of children with CP, although the 100% feedback group consistently demonstrated less error. INTERPRETATION: Children with CP use feedback in a manner similar to children with typical development when learning new skills with their less involved hand, but demonstrate less accuracy and consistency.

Validating the Fatigue Scale for Motor and Cognitive Function (FSMC) in chronic stroke.

BACKGROUND: Post-stroke fatigue can manifest as both physical and mental fatigue. The Fatigue Scale for Motor and Cognitive Functions (FSMC) evaluates fatigue on the motor and cognitive domains separately, however, the psychometric properties of this measure in stroke have not been reported. OBJECTIVE: To determine the internal consistency, test-retest reliability, and concurrent validity of the FSMC in chronic stroke. METHODS: Thirty-four participants with chronic stroke (55.26±12.27 years of age; 59.53±89.21 months post-stroke) completed the FSMC on two separate visits. Internal consistency and reliability of the FSMC were examined using Cronbach's alpha and two-way mixed effects intraclass correlation coefficients (ICC), respectively. Correlation between the FSMC and the Fatigue Severity Scale and Visual Analog Scale-Fatigue was used to assess concurrent validity. RESULTS: Internal consistency was excellent (Cronbach's alpha > 0.9) and reliability was moderate to good (ICC = 0.72-0.81) for all FSMC scores. The FSMC demonstrated moderate to good concurrent validity with the Fatigue Severity Scale (ρ= 0.66-0.72) but only fair concurrent validity with the Visual Analog Scale-Fatigue (ρ= 0.37-0.44). CONCLUSION: The FSMC is a valid and reliable measure of post-stroke fatigue and may be a useful tool to examine physical fatigue and cognitive fatigue in chronic stroke.

Neural correlates of dual-task practice benefit on motor learning: a repetitive transcranial magnetic stimulation study.

Dual-task practice has been previously shown to enhance motor learning when both primary and secondary tasks engage similar cognitive processes. In the present study, participants practiced a finger sequence task with the non-dominant hand under a single-task condition (i.e. without a probe task) or a dual-task condition in which a probe choice reaction time (CRT) task was presented during the preparation phase (before movement onset) of the finger task. It was hypothesised that by engaging similar 'planning' processes, the dual-task condition may facilitate the activation of shared 'planning' circuitry that includes dorsal premotor cortex (dPM), an important neural substrate for CRT task performance and movement preparation. Repetitive transcranial magnetic stimulation (rTMS; 1 Hz) was applied to the contralateral dPM immediately following practice. Motor learning was assessed by a retention test conducted ~ 24 h after practice. Consistent with our previous results, the dual-task condition enhanced learning compared with the single-task condition. rTMS applied to dPM attenuated the dual-task practice benefit on motor learning. In contrast, rTMS to M1 did not attenuate the dual-task practice benefit, suggesting the rTMS effect was specific to dPM. Our findings suggest a unique role of dPM in mediating the dual-task practice effect on motor learning.

Memory-Guided Reaching: Is It Effortful?

We previously showed that perceived effort during visually guided reaching was altered as task demand varied. Further, self-reported subjective fatigue correlated with perceived effort and reach performance under visually guided conditions. Memory-guided reaching often leads to performance deterioration and can provide insights about the planning and control of reach actions. It is unclear how perceived effort changes during memory-guided reaching and whether self-reported subjective fatigue is associated with perceived effort of memory-guided reaching. Twenty-three young adults performed reach actions under visually- and memory-guided conditions. Perceived effort, reaction time, and endpoint error increased significantly from the visually- to the memory-guided condition. Self-reported subjective fatigue was associated with perceived effort and reach distance error during memory-guided reaching; those with higher levels of fatigue reported greater perceived effort and tended to reach farther when visual information was not available. These findings establish a foundation to examine relationships between subjective fatigue, perceived effort, and reach control.

Optimal timing and neural loci: a scoping review on the effect of non-invasive brain stimulation on post-stroke gait and balance recovery.

BACKGROUND: Little is known about the optimal timing and neural loci for applying noninvasive brain stimulation (NIBS) to promote gait and balance recovery after stroke. OBJECTIVE: To identify the optimal timing and neural loci of NIBS for gait and balance recovery after stroke. METHODS: We performed a PubMed search using keywords of stroke, transcranial magnetic stimulation, transcranial direct current stimulation, NIBS, balance, and gait. Interventional trials with various designs published in English were selected. Both flowcharts and tables were used for the result presentation. RESULTS: The majority of selected 31 studies included individuals with chronic stroke and primary motor cortex (M1) stimulation. Studies' quality ranged from 4 to 10 (max = 10) on the Pedro scale. NIBS led to improvements in gait and balance in individuals with chronic and subacute stroke, yet the evidence for the acute phase of stroke is limited. Further, stimulation over the ipsilesional M1 resulted in improvement in gait and balanced performance. Stimulation over non-motor regions such as the cerebellum has been limitedly explored. CONCLUSION: Current evidence supports the use of NIBS to the M1 in conjunction with behavioral training to improve gait and balance performance in individuals with subacute and chronic stroke. Future research is recommended to evaluate the effect of NIBS during acute stroke and over neural loci other than M1, and to implement a more rigorous method.

Dual-task practice enhances motor learning: a preliminary investigation.

Practicing a motor task under dual-task conditions can be beneficial to motor learning when the secondary task is difficult (Roche et al. in Percept Psychophys 69(4):513-522, 2007) or when it engages similar processes as the primary motor task (Hemond et al. in J Neurosci 30(2):650-654, 2010). The purpose of this pilot study was to determine which factor, difficulty level or engaged processes, of a secondary task is more critical in determining dual-task benefit. Participants practiced a discrete arm task in conjunction with an audio-vocal reaction time (RT) task. We presented two different RT tasks that differed in difficulty, simple versus choice (i.e., more difficult), at two different arm task phases that differed in engaged processes, preparation versus execution, resulting in four dual-task conditions. A simple RT task is thought to predominantly engage motor execution processes, therefore would engage similar processes as the arm movement task when it is presented during the execution phase, while a choice RT task is thought to engage planning processes and therefore would engage similar processes too when it is presented during the preparation phase. Enhanced motor learning was found in those who engaged similar process as the primary task during dual-tasking (i.e., choice RT presented during preparation and simple RT presented during execution). Moreover, those who showed enhanced learning also demonstrated high dual-task cost (poor RT task performance) during practice, indicating that both tasks were taxing the same resource pool possibly due to engaging similar cognitive processes. To further test the relation between dual-task cost and enhanced learning, we delayed the presentation timing of the choice RT task during the preparation phase and the simple RT task during the execution phase in two control experiments. Dual-task cost was reduced in these delayed timing conditions, and the enhanced learning effect was attenuated. Together, our preliminary findings suggest that it is the similarity hypothesis and not the difficulty hypothesis that mediates the enhanced motor learning under dual-task conditions.

Perceived effort for reaching is associated with self-reported fatigue.

Perceived effort for goal-directed reaching may be impacted by the level of self-reported fatigue, however, the relationship between self-reported fatigue and perceived effort has not been examined. We examined how perceived effort changed under varied reach conditions and the relationship between fatigue, perceived effort and reach performance. Twenty-three young adults performed reach actions toward 9 different targets on a digitizing tablet. Perceived effort was measured using the Borg Rate of Perceived Exertion and Paas Mental Effort Rating Scale. Self-reported fatigue was quantified using the Fatigue Scales for Motor and Cognitive Functions. As reach conditions became more difficult, perceived effort increased significantly. Further, individuals who reported greater fatigue also reported greater perceived effort and showed greater endpoint error during reaching.

Mechanisms of the contextual interference effect in individuals poststroke.

Although intermixing different motor learning tasks via random schedules enhances long-term retention compared with "blocked" schedules, the mechanism underlying this contextual interference effect has been unclear. Furthermore, previous studies have reported inconclusive results in individuals poststroke. We instructed participants to learn to produce three grip force patterns in either random or blocked schedules and measured the contextual interference effect by long-term forgetting: the change in performance between immediate and 24-h posttests. Nondisabled participants exhibited the contextual interference effect: no forgetting in the random condition but forgetting in the blocked condition. Participants at least 3 mo poststroke exhibited no forgetting in the random condition but marginal forgetting in the blocked condition. However, in participants poststroke, the integrity of visuospatial working memory modulated long-term retention after blocked schedule training: participants with poor visuospatial working memory exhibited little forgetting at 24 h. These counterintuitive results were predicted by a computational model of motor memory that contains a common fast process and multiple slow processes, which are competitively updated by motor errors. In blocked schedules, the fast process quickly improved performance, therefore reducing error-driven update of the slow processes and thus poor long-term retention. In random schedules, interferences in the fast process led to slower change in performance, therefore increasing error-driven update of slow processes and thus good long-term retention. Increased forgetting rates in the fast process, as would be expected in individuals with visuospatial working memory deficits, led to small updates of the fast process during blocked schedules and thus better long-term retention.

Single session of repetitive transcranial magnetic stimulation to left dorsolateral prefrontal cortex increased dual-task gait speed in chronic stroke: A pilot study.

BACKGROUND: Individuals with stroke often experience difficulty in dual-task walking and are prone to falling when walking and talking. Previous studies in other populations have suggested that non-invasive brain stimulation could enhance dual-task gait performance by stimulating dorsolateral prefrontal cortex (DLPFC) or supplementary motor area (SMA). It was unclear if the benefits of brain stimulation would be observed in individuals with stroke. RESEARCH QUESTION: Would single-session 5 Hz rTMS applied to DLPFC or SMA improve dual-task gait performance in individuals with stroke? METHODS: This single group repeated measure study included fifteen individuals with left chronic stroke (mean age = 58 years). Participants received 5 Hz rTMS to either DLPFC, SMA, or M1 of the left lesioned hemisphere across three different sessions. Single- and dual-task gait speed was assessed before and after rTMS with the dualtask gait being walking and counting backward by 3 s. RESULTS: We observed that rTMS to left DLPFC resulted in a greater increase in dual-task gait speed, but not single-task gait speed, compared to the other two stimulation sites (M1 and SMA) but the difference was not statistically significant (p = 0.06). Five out of fifteen participants demonstrated a clinically significant improvement in dual-task gait speed (> 0.1 m/s) after rTMS to DLPFC. SIGNIFICANCES: The results suggest that DLPFC could be a potential treatment target to improve dual-task gait performance in persons with chronic stroke.

Facilitation of supplementary motor area excitability improves dual-task walking in young adults.

Activations of the DLPFC and SMA have been shown to correlate with dual-task walking. However, very few investigations have directly perturbed the activations of these areas to establish a cause-and-effect relationship. The objectives of this study were: 1) to investigate the role of DLPFC and SMA in dual-task walking using rTMS and 2) to determine whether the secondary task difficulty mediates the roles of these cortical areas. Nineteen young healthy adults were divided into two groups: Count-by-3 s (N = 9) and Count-by-7 s (N = 10) groups. During dualtask walking, the Count-by-3 s group walked and counted backward by 3 s while the other group counted backward by 7. Each participant received facilitatory rTMS (5 Hz) administered to the left DLPFC, SMA and M1 across 3 sessions (approximately a week apart). Single- and dual-task walking were assessed both before and after rTMS. Gait speed under the 2 walking conditions was analyzed with repeated measure ANOVA. rTMS to the SMA significantly increased dual-task walking speed (p = .02) but not singletask walking speed. In contrast, rTMS to the DLPFC or M1 did not result in any significant changes in gait speed. Secondary task difficulty did not moderate the effects of rTMS on dual-task gait because both groups had similar changes in gait performance after rTMS. SMA is an important neural substrate mediating dual-task walking and might be a therapeutic target for gait intervention.

Social Participation Determines Quality of Life Among Urban-Dwelling Older Adults With Stroke in a Developing Country.

BACKGROUND AND PURPOSE: Poor quality of life (QoL) is a well-recognized consequence after stroke. Quality of life is influenced by a complex interaction between personal and environmental factors. Most previous investigations of the QoL after stroke have focused on personal factors, for example, physical deficits directly resulting from stroke. The influence of environmental factors, including social participation, is relatively understudied partly due to its high variation across different sociocultural contexts. The purpose of this study was to investigate the determinants of QoL among older adults with stroke living in an urban area of a developing country. METHODS: This cross-sectional observational study included 75 older adults who were at least 3 months poststroke and 50 age-matched healthy controls. Depressive symptoms were quantified using the World Health Organization Quality of Life Brief version (WHOQoL-BREF). Physical function was examined using Functional Ambulation Category, grip strength, 5 times Sit-to-Stand test, and Box and Block tests. The Montreal Cognitive Assessment and visual-manual reaction time were used to index cognitive function. Depressive symptom was quantified using the Patient Health Questionnaire-9. The Barthel Index and Fatigue Severity Scale were used to quantify activity limitation. Social participation and environmental participation were assessed using the Assessment of Life Habit and Craig Hospital Inventory of Environment Factors, respectively. Linear stepwise regression models were used to determine explanators for WHOQoL-BREF domain scores. RESULTS: Individuals with stroke demonstrated significantly worse QoL on all WHOQoL-BREF domains compared with healthy controls. Stroke was a strong determinant for QoL and explained 16% to 43% of variances. Adding other outcome measures significantly improved the robustness of the models (R change = 12%-32%). The physical, psychological, social, and environmental domains of WHOQoL-BREF were all explained by the LIFE-H scores (ß = -10.58, -3.37, 4.24, -5.35, respectively), while psychological, social, and environmental domains were explained by Montreal Cognitive Assessment scores (ß = .47, 0.78, 0.54, respectively). CONCLUSION: Social participation and cognition were strong determinants of QoL among urban-dwelling older adults with stroke. Social and recreational activities and cognitive rehabilitation should therefore be evaluated as potential strategies to improve the well-being of older adults affected by stroke.

Axial Segmental Coordination During Turning: Effects of Stroke and Attentional Loadings.

Attentional loadings deteriorate straight walking performance for individuals poststroke, but its effects on turning while walking remain to be determined. Here we compared turning kinematics under three attentional loading conditions (single, dual-motor, and dual-cognitive task) between stroke survivors and healthy controls. Nine chronic stroke survivors and 10 healthy controls performed the Timed Upand- Go test while their full-body kinematics were recorded. Onset times of yaw rotation of the head, thorax and pelvis segments and head anticipation distance were used to quantify turning coordination. Results showed that stroke survivors reoriented their body segments much earlier than the controls, but they preserved the similar segmental reorientation sequence under the single-task condition. For the healthy controls, attentional loading led to an earlier axial segment reorientation, but the reorientation sequence was preserved. In contrast, the dual-cognitive task condition led to a disrupted reorientation sequence in stroke. The results indicate that turning coordination was altered in individuals poststroke, especially under the dual-task interference.

Test-retest reliability, internal consistency and concurrent validity of Fatigue Severity Scale in measuring post-stroke fatigue.

BACKGROUND: Post-stroke fatigue (PSF) is a common complaint among stroke survivors and has significant impacts on recovery and quality of life. Limited tools that measure fatigue have been validated in stroke. AIM: The purpose of this study was to determine the psychometric properties of Fatigue Severity Scale (FSS) in patients with stroke. DESIGN: Cross-sectional study. SETTING: Teaching hospital outpatient setting. POPULATION: Fifty healthy controls (mean age 61.1±7.4 years; 22 males) and 50 patients with stroke (mean age 63.6±10.3 years; 34 males). METHODS: FSS was administered twice approximately a week apart through face-to-face interview. In addition, we measured fatigue with Visual Analogue Scale - Fatigue (VAS-F) and Short-Form Health Survey 36 version 2 vitality scale. We used Cronbach alpha to determine internal consistency of FSS. Reliability and validity of FSS were determined by intraclass correlation coefficient (ICC) and Spearman correlation coefficient (r). RESULTS: FSS showed excellent internal consistency for both stroke and healthy groups (Cronbach's alpha >0.90). FSS had excellent test-retest reliability for stroke patients and healthy controls (ICC=0.93 and ICC=0.90, respectively). The scale demonstrated good concurrent validity with VAS-Fatigue (all r>.60) and a moderate validity with the SF36-vitality scale. Furthermore, FSS was sensitive to distinguish fatigue in stroke from the healthy controls (P<0.01). CONCLUSIONS: FSS has excellent internal consistency, test-retest reliability and good concurrent validity with VAS-F for both groups. CLINICAL REHABILITATION IMPACT: This study provides evidence that FSS is a reliable and valid tool to measure post-stroke fatigue and is readily to be used in clinical settings.

Test-Retest Reliability and Validity of the Malay Version Life Habits Assessment (LIFE-H 3.1) to Measure Social Participation in Adults With Physical Disabilities.

BACKGROUND AND PURPOSE: Social participation restriction is a common barrier encountered by older adults and individuals with physical disabilities. To best direct the limited resource to support social services for individuals with disability, there is a need to objectively measure social participation restriction. A number of tools to measure levels of social participation are available, but none of them has been translated into the Malay language. This cross-sectional study examined the test-retest reliability and concurrent validity of the Life Habits Assessment (LIFE-H 3.1) that had been translated and culturally adapted to the Malay language. METHODS: Seventy-five individuals with physical disabilities (age, mean [standard deviation] = 58 [10] years; 49 males) participated in this study. Participants were interviewed twice with the Malay version LIFE-H 3.1, approximately 1 week apart. The Barthel Index (BI) and the World Health Organization Assessment of Quality of Life-Brief version (WHOQoL-BREF) were administered in the first interview as well. Intraclass correlation coefficients and the Bland-Altman Bias D were used to examine test-retest reliability. The Spearman correlation coefficients were computed to quantify the correlation between the Malay version LIFE-H 3.1 and the BI and the WHOQoL-BREF, respectively, to examine the concurrent validity of the Malay version LIFE-H 3.1. Furthermore, standard error of measurement and minimal detectable change were calculated. RESULTS: The Malay version LIFE-H 3.1 had excellent test-retest reliability as evidenced by good to excellent intraclass correlation coefficients (0.71-0.95) and minimal Bland-Altman biases (0.01-0.12). The correlations between the Malay version LIFE-H 3.1 and the BI were fair to good (r = 0.28-0.69). The correlations between the Malay version LIFE-H 3.1 and the WHOQoL-BREF were weak to fair, ranging from 0.02 to 0.57. CONCLUSIONS: The Malay version LIFE-H 3.1 demonstrates excellent test-retest reliability and satisfactory validity. This questionnaire is an appropriate tool to assess social participation in rehabilitation for native Malay language speakers.