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Real-time functional MRI neurofeedback allows individuals to self-modulate their ongoing brain activity. This may be a useful tool in clinical disorders that are associated with altered brain activity patterns. Motor impairment after stroke has previously been associated with decreased laterality of motor cortex activity. Here we examined whether chronic stroke survivors were able to use real-time fMRI neurofeedback to increase laterality of motor cortex activity and assessed effects on motor performance and on brain structure and function. We carried out a randomized, double-blind, sham-controlled trial (ClinicalTrials.gov: NCT03775915) in which 24 chronic stroke survivors with mild to moderate upper limb impairment experienced three training days of either Real (n = 12) or Sham (n = 12) neurofeedback. Assessments of brain structure, brain function and measures of upper-limb function were carried out before and 1 week after neurofeedback training. Additionally, measures of upper-limb function were repeated 1 month after neurofeedback training. Primary outcome measures were (i) changes in lateralization of motor cortex activity during movements of the stroke-affected hand throughout neurofeedback training days; and (ii) changes in motor performance of the affected limb on the Jebsen Taylor Test (JTT). Stroke survivors were able to use Real neurofeedback to increase laterality of motor cortex activity within (P = 0.019), but not across, training days. There was no group effect on the primary behavioural outcome measure, which was average JTT performance across all subtasks (P = 0.116). Secondary analysis found improvements in the performance of the gross motor subtasks of the JTT in the Real neurofeedback group compared to Sham (P = 0.010). However, there were no improvements on the Action Research Arm Test or the Upper Extremity Fugl–Meyer score (both P > 0.5). Additionally, decreased white-matter asymmetry of the corticospinal tracts was detected 1 week after neurofeedback training (P = 0.008), indicating that the tracts become more similar with Real neurofeedback. Changes in the affected corticospinal tract were positively correlated with participants neurofeedback performance (P = 0.002). Therefore, here we demonstrate that chronic stroke survivors are able to use functional MRI neurofeedback to self-modulate motor cortex activity in comparison to a Sham control, and that training is associated with improvements in gross hand motor performance and with white matter structural changes.

Stroke is frequently accompanied by long-term sleep disruption. We therefore aimed to assess the efficacy of digital cognitive behavioural therapy (dCBT) for insomnia to improve sleep after stroke. A parallel group randomised controlled trial was conducted remotely in participant’s homes/online. Randomisation was online with minimisation of between-group differences in age and baseline Sleep Condition Indicator (SCI-8) score. In total, 86 community dwelling stroke survivors consented, of whom 84 completed baseline assessments (39 female, mean 5.5 years post-stroke, mean 59 years of age) and were randomised to dCBT or control (sleep hygiene information). Follow-up was completed at post-intervention (mean 75 days after baseline) and 8-weeks later. The primary outcome was self-reported insomnia symptoms, as per the SCI-8 (range 0-32, lower numbers indicate more severe insomnia, reliable change 7-points) at post-intervention. There were significant improvements in SCI-8 for dCBT compared to control (intention-to-treat, dCBT n=48, control n=36, 5 imputed datasets, effect of group p≤0.02, ηp2=0.07–0.12, pooled mean difference=-3.35). Additionally, secondary outcomes showed shorter self-reported sleep onset latencies and better mood for the dCBT group, but no significant differences for self-efficacy, quality of life, or actigraphy-derived sleep parameters. Cost-effectiveness analysis found that dCBT dominates over control (non-significant cost savings and higher quality adjusted life years). No related serious adverse events were reported to the researchers. Overall, dCBT for insomnia effectively improves sleep after stroke. Future research is needed to assess earlier stages post-stroke, with a longer follow-up period to determine whether it should be included as part of routine post-stroke care.Clinicaltrials.govNCT04272892

Background. Stroke survivors commonly complain of difficulty sleeping. Poor sleep is associated with reduced quality of life and more understanding of long-term consequences of stroke on sleep is needed. Objective. The primary aims were to (1) compare sleep measures between chronic stroke survivors and healthy controls and (2) test for a relationship between motor impairment, time since stroke and sleep. Secondary aims were to explore mood and inactivity as potential correlates of sleep and test the correlation between self-reported and objective sleep measures. Methods. Cross-sectional sleep measures were obtained for 69 chronic stroke survivors (mean 65 months post-stroke, 63 years old, 24 female) and 63 healthy controls (mean 61 years old, 27 female). Self-reported sleep was assessed with the sleep condition indicator (SCI) and sleep diary ratings, objective sleep with 7-nights actigraphy and mood with the Hospital Anxiety and Depression Scale. Upper extremity motor impairment was assessed with the Fugl-Meyer assessment. Results. Stroke survivors had significantly poorer SCI score ( P < .001) and higher wake after sleep onset ( P = .005) than controls. Neither motor impairment, nor time since stroke, explained significant variance in sleep measures for the stroke group. For all participants together, greater depression was associated with poorer SCI score ( R2adj = .197, P < .001) and higher age with more fragmented sleep ( R2adj = .108, P < .001). There were weak correlations between nightly sleep ratings and actigraphy sleep measures ( r s = .15–.24). Conclusions. Sleep disturbance is present long-term after stroke. Depressive symptoms may present a modifiable factor which should be investigated alongside techniques to improve sleep in this population.

Objective: To test the extent to which initial walking speed influences dual-task performance after walking intervention, hypothesising that slow walking speed affects automatic gait control, limiting executive resource availability. Design: A secondary analysis of a trial of dual-task (DT) and single-task (ST) walking interventions comparing those with good (walking speed ⩾0.8 m s−1, n = 21) and limited (walking speed −1, n = 24) capacity at baseline. Setting: Community. Subjects: Adults six-months post stroke with walking impairment. Interventions: Twenty sessions of 30 minutes treadmill walking over 10 weeks with (DT) or without (ST) cognitive distraction. Good and limited groups were formed regardless of intervention received. Main measures: A two-minute walk with (DT) and without (ST) a cognitive distraction assessed walking. fNIRS measured prefrontal cortex activation during treadmill walking with (DT) and without (ST) Stroop and planning tasks and an fMRI sub-study used ankle-dorsiflexion to simulate walking. Results: ST walking improved in both groups (∆baseline: Good = 8.9 ± 13.4 m, limited = 5.3±8.9 m, Group × time = P Conclusion: In individual who walk slowly it may be difficult to improve dual-task walking ability. Registration: ISRCTN50586966

Objective Sleep is commonly impaired after stroke. Cognitive Behavioral Therapy for Insomnia (CBT-I) is the first-line recommended treatment for sleep difficulty. “Sleepio” is a digital CBT-I program, allowing delivery of this treatment at scale. However, Sleepio has not yet been tested specifically in people with stroke. Before doing so, we wanted to explore the experience of people with stroke using the program, and potential barriers to completion. Method Community dwelling survivors of stroke (n = 11, 41–78 years of age, 6 male) were given access to Sleepio. Participants discussed their experiences with the program during a semi-structured interview, which was analyzed using thematic analysis. Results We found four common themes: (1) positive and negative experiences impacted engagement with the program, (2) motivation to follow the program was proportional to perceived severity of sleep problem, (3) impractical advice for people with stroke, (4) difficulty operating the program. Conclusion Sleepio can be used by some people at the chronic stage of stroke. However, some barriers to completion were highlighted, and not all suggestions were deemed practical for everyone. We therefore suggest possible adaptations which may make the program more easily usable and engaging for survivors of stroke with varying impairments.

IntroductionConsolidation of motor skill learning, a key component of rehabilitation post-stroke, is known to be sleep dependent. However, disrupted sleep is highly prevalent after stroke and is often associated with poor motor recovery and quality of life. Previous research has shown that digital cognitive behavioural therapy (dCBT) for insomnia can be effective at improving sleep quality after stroke. Therefore, the aim of this trial is to evaluate the potential for sleep improvement using a dCBT programme, to improve rehabilitation outcomes after stroke.Methods and analysisWe will conduct a parallel-arm randomised controlled trial of dCBT (Sleepio) versus treatment as usual among individuals following stroke affecting the upper limb. Up to 100 participants will be randomly allocated (2:1) into either the intervention (6–8 week dCBT) or control (continued treatment as usual) group. The primary outcome of the study will be change in insomnia symptoms pre to post intervention compared with treatment as usual. Secondary outcomes include improvement in overnight motor memory consolidation and sleep measures between intervention groups, correlations between changes in sleep behaviour and overnight motor memory consolidation in the dCBT group and changes in symptoms of depression and fatigue between the dCBT and control groups. Analysis of covariance models and correlations will be used to analyse data from the primary and secondary outcomes.Ethics and disseminationThe study has received approval from the National Research Ethics Service (22/EM/0080), Health Research Authority (HRA) and Health and Care Research Wales (HCRW), IRAS ID: 306 291. The results of this trial will be disseminated via presentations at scientific conferences, peer-reviewed publication, public engagement events, stakeholder organisations and other forms of media where appropriate.Trial registration numberNCT05511285.

Real-time functional magnetic resonance imaging (fMRI) neurofeedback allows individuals to self-modulate their ongoing brain activity. This may be a useful tool in clinical disorders which are associated with altered brain activity patterns. Motor impairment after stroke has previously been associated with decreased laterality of motor cortex activity. Here we examined whether chronic stroke survivors were able to use real-time fMRI neurofeedback to increase laterality of motor cortex activity and assessed effects on motor performance and on brain structure and function. We carried out a randomized, double-blind, sham-controlled trial in which 24 chronic stroke survivors with mild to moderate upper limb impairment experienced three training days of either Real (n=12) or Sham (n=12) neurofeedback. Stroke survivors were able to use Real neurofeedback to increase laterality of motor cortex activity within, but not across, training days. Improvement in gross hand motor performance assessed by the Jebsen Taylor Test (JTT) was observed in the Real neurofeedback group compared to Sham. However, there were no improvements on the Action Research Arm Test (ARAT) or the Upper Extremity Fugl-Meyer (UE-FM) score. Additionally, decreased white-matter asymmetry of the corticospinal tracts was detected 1-week after neurofeedback training, indicating that the tracts become more similar with Real neurofeedback. Changes in the affected corticospinal tract was positively correlated with neurofeedback performance. Therefore, here we demonstrate that chronic stroke survivors are able to use fMRI neurofeedback to self-modulate motor cortex activity, and that training is associated with improvements in hand motor performance and with white matter structural changes.

Background and AimsSleep is important for consolidation of motor learning, but brain injury may affect sleep continuity and therefore rehabilitation outcomes. This study aims to assess the relationship between sleep quality and motor recovery in brain injury patients receiving inpatient rehabilitation.Methods59 patients with brain injury were recruited from two specialist inpatient rehabilitation units. Sleep quality was assessed (up to 3 times) objectively using actigraphy (7 nights) and subjectively using the Sleep Condition Indicator. Motor outcome assessments included: Action Research Arm test (upper limb function), Fugl Meyer assessment (motor impairment) and the Rivermead Mobility Index. The functional independence measure (FIM) was assessed at admission and discharge by the clinical team. 55 age and gender matched healthy controls completed one assessment.ResultsInpatients demonstrated lower self-reported sleep quality (p2adj = 0.12, p = 0.03), whereby more disrupted sleep was associated with slower recovery.ConclusionsInpatients with brain injury demonstrate impaired sleep quality, and this is associated with poorer motor outcomes and slower functional recovery. Further investigation is needed to determine how sleep quality can be improved and whether this affects outcome.

Motor sequence learning is important for stroke recovery, but experimental tasks require dexterous movements, which are impossible for people with upper limb impairment. This makes it difficult to draw conclusions about the impact of stroke on learning motor sequences. We aimed to test a paradigm requiring gross arm movements to determine whether stroke survivors with upper limb impairment were capable of learning a movement sequence as effectively as age-matched controls.In this case-control study, 12 stroke survivors (10-138 months post-stroke, mean age 64 years) attempted the task once using their affected arm. Ten healthy controls (mean 66 years) used their non-dominant arm. A sequence of 10 movements was repeated 25 times. The variables were: time from target illumination until the cursor left the central square (onset time; OT), accuracy (path length), and movement speed.OT reduced with training (p 0.05) for both groups, with no change in movement speed or accuracy (p 0.1). We quantified learning as the OT difference between the end of training and a random sequence; this was smaller for stroke survivors than controls (p = 0.015).Stroke survivors can learn a movement sequence with their paretic arm, but demonstrate impairments in sequence specific learning. Implications for Rehabilitation Motor sequence learning is important for recovery of movement after stroke. Stroke survivors were found to be capable of learning a movement sequence with their paretic arm, supporting the concept of repetitive task training for recovery of movement. Stroke survivors showed impaired sequence specific learning in comparison with age-matched controls, indicating that they may need more repetitions of a sequence in order to re-learn movements. Further research is required into the effect of lesion location, time since stroke, hand dominance and gender on learning of motor sequences after stroke.

Transcranial direct current stimulation (tDCS) has the potential to improve motor function in a range of neurological conditions, including Cerebral Palsy (CP). Although there have been many studies assessing tDCS in adult stroke, the literature regarding the efficacy of tDCS in CP is more limited. This review therefore focuses on the neurophysiological and clinical findings in children and adolescents with CP. Initial studies applying anodal tDCS to promote lower limb function are promising, with improvements in gait, mobility and balance reported. However, the results of upper limb studies are mixed and more research is needed. Studies investigating neurophysiological changes or predictors of response are also lacking. Large-scale longitudinal studies are needed for the lower limb to ascertain whether the initial pilot results translate into clinically meaningful improvements. Future studies of the upper limb should focus on determining the optimal stimulation parameters and consider tailoring stimulation to the individual based on the (re)organisation of their motor system.

Objective To assess the impact of electrode arrangement on the efficacy of tDCS in stroke survivors and determine whether changes in transcallosal inhibition (TCI) underlie improvements. Methods 24 stroke survivors (3–124 months post-stroke) with upper limb impairment participated. They received blinded tDCS during a motor sequence learning task, requiring the paretic arm to direct a cursor to illuminating targets on a monitor. Four tDCS conditions were studied (crossover); anodal to ipsilesional M1, cathodal to contralesional M1, bihemispheric, sham. The Jebsen Taylor hand function test (JTT) was assessed pre- and post-stimulation and TCI assessed as the ipsilateral silent period (iSP) duration using transcranial magnetic stimulation. Results The time to react to target illumination reduced with learning of the movement sequence, irrespective of tDCS condition (p > 0.1). JTT performance improved after unilateral tDCS (anodal or cathodal) compared with sham (p < 0.05), but not after bihemispheric (p > 0.1). There was no effect of tDCS on change in iSP duration (p > 0.1). Conclusions Unilateral tDCS is effective for improving JTT performance, but not motor sequence learning. Significance This has implications for the design of future clinical trials.

The selective serotonin reuptake inhibitor fluoxetine significantly enhances adult visual cortex plasticity within the rat. This effect is related to decreased gamma-aminobutyric acid (GABA) mediated inhibition and identifies fluoxetine as a potential agent for enhancing plasticity in the adult human brain. We tested the hypothesis that fluoxetine would enhance visual perceptual learning of a motion direction discrimination (MDD) task in humans. We also investigated 1) the effect of fluoxetine on visual and motor cortex excitability and 2) the impact of increased GABA mediated inhibition following a single dose of triazolam on post-training MDD task performance. Within a double blind, placebo controlled design, 20 healthy adult participants completed a 19-day course of fluoxetine (n = 10, 20mg per day) or placebo (n = 10). Participants were trained on the MDD task over the final five days of fluoxetine administration. Accuracy for the trained MDD stimulus and an untrained MDD stimulus configuration was assessed before and after training, after triazolam and one week after triazolam. Motor and visual cortex excitability was measured using transcranial magnetic stimulation. Fluoxetine did not enhance the magnitude or rate of perceptual learning and full transfer of learning to the untrained stimulus was observed for both groups. After training was complete, trazolam had no effect on trained task performance but significantly impaired untrained task performance. No consistent effects of fluoxetine on cortical excitability were observed. The results do not support the hypothesis that fluoxetine can enhance learning in humans. However, the specific effect of triazolam on MDD task performance for the untrained stimulus suggests that learning and learning transfer relay on dissociable neural mechanisms.

Non-invasive brain stimulation (NIBS) is promising as an adjuvant to rehabilitation of motor function after stroke. Despite numerous studies and reviews for the upper limb, NIBS targeting the lower limb and gait recovery after stroke is a newly emerging field of research.To summarize findings from studies using NIBS to target the lower limb in stroke survivors.This narrative review describes studies of repetitive transcranial magnetic stimulation, paired associative stimulation and transcranial direct current stimulation with survivors of stroke.NIBS appears capable of inducing changes in cortical excitability and lower limb function, but stimulation parameters and study designs vary considerably making it difficult to determine effectiveness.Future research should systematically assess differences in response with different stimulation parameters, test measures for determining who would be most likely to benefit and assess effectiveness with large samples before NIBS can be considered for use in clinical practice. Implications for Rehabilitation Stroke is a leading cause of disability, often resulting in dependency in activities of daily living and reduced quality of life. Non-invasive brain stimulation has received considerable interest as a potential adjuvant to rehabilitation after stroke and this review summarizes studies targeting the lower limb and gait recovery. Non-invasive brain stimulation can be used to modulate excitability of lower limb muscle representations and can lead to improvements in motor performance in stroke survivors. Non-invasive brain stimulation for gait recovery needs further investigation before translation to clinical practice is possible.

The objective of this study was to investigate reliability of transcranial magnetic stimulation (TMS) parameters for three coil systems; hand-held circular and figure-of-eight and navigated figure-of-eight coils. Stimulus response curves, intracortical inhibition (SICI) and facilitation (ICF) were studied in the right first dorsal interosseus muscle of 10 healthy adults. Each coil system was tested twice per subject. Navigation was conducted by a custom built system. Cortical excitability showed moderate-to-good reliability for the hand-held and navigated figure-of-eight coils (Intraclass correlation coefficients (ICCs) 0.55-0.89). The circular coil showed poor reliability for motor evoked potential (MEP) amplitude at 120% resting motor threshold (RMT; MEP(120)) and MEP sum (ICCs 0.090.48). Reliability for SICI was good for all coil systems when an outlier was removed (ICCs 0.87-0.93), but poor for ICF (ICCs0.3). The circular coil had a higher MEP(120) than the navigated figure-of-eight coil (p = 0.004). Figure-of-eight coils can be used confidently to investigate cortical excitability over time. ICF should be interpreted with caution. The navigation device frees the experimenter and enables tracking of the position of the coil and subject. The results help guide the choice of coil system for longitudinal measurements of motor cortex function.

After stroke, the function of primary motor cortex (M1) between the hemispheres may become unbalanced. Techniques that promote a re-balancing of M1 excitability may prime the brain to be more responsive to rehabilitation therapies and lead to improved functional outcomes. The present study examined the effects of Active-Passive Bilateral Therapy (APBT), a putative movement-based priming strategy designed to reduce intracortical inhibition and increase excitability within the ipsilesional M1. Thirty-two patients with upper limb weakness at least 6 months after stroke were randomized to a 1-month intervention of self-directed motor practice with their affected upper limb (control group) or to APBT for 10-15 min prior to the same motor practice (APBT group). A blinded clinical rater assessed upper limb function at baseline, and immediately and 1 month after the intervention. Transcranial magnetic stimulation was used to assess M1 excitability. Immediately after the intervention, motor function of the affected upper limb improved in both groups (P < 0.005). One month after the intervention, the APBT group had better upper limb motor function than control patients (P < 0.05). The APBT group had increased ipsilesional M1 excitability (P < 0.025), increased transcallosal inhibition from ipsilesional to contralesional M1 (P < 0.01) and increased intracortical inhibition within contralesional M1 (P < 0.005). None of these changes were found in the control group. APBT produced sustained improvements in upper limb motor function in chronic stroke patients and induced specific and sustained changes in motor cortex inhibitory function. We speculate that APBT may have facilitated plastic reorganization in the brain in response to motor therapy. The utility of APBT as an adjuvant to physical therapy warrants further consideration.

Determining whether a person with stroke has reached their full potential for recovery is difficult. While techniques such as transcranial magnetic stimulation (TMS) and MRI have some prognostic value, their role in rehabilitation is undefined. This study used TMS and MRI to determine which factors predict functional potential, defined as an individual's capacity for further functional improvement at least 6 months following stroke. We studied 21 chronic stroke patients with upper limb impairment. The functional integrity of the corticospinal tracts (CSTs) was assessed using TMS and functional MRI. The presence or absence of motor-evoked responses (MEPs) to TMS in the affected upper limb, and the lateralization of cortical activity during affected hand use were determined. The structural integrity of the CST was assessed using MRI, and diffusion tensor imaging was used to measure the asymmetry in fractional anisotropy (FA) of the internal capsules. A multiple linear regression analysis was performed, to predict both clinical score at inception and change in clinical score for 17 patients who completed a 30 day programme of motor practice with the affected upper limb. The main findings were that in patients with MEPs, meaningful gains were still possible 3 years after stroke, although the capacity for improvement declined with time. In patients without MEPs, functional potential declines with increasing CST disruption, with no meaningful gains possible if FA asymmetry exceeds a value of 0.25. This study is the first to demonstrate the complementary nature of TMS and MRI techniques in predicting functional potential in chronic stroke patients. An algorithm is proposed for the selection of individualized rehabilitation strategies, based on the prediction of functional potential. These strategies could include neuromodulation using a range of emerging techniques, to prime the motor system for a plastic response to rehabilitation.

Most studies of motor imagery have examined motor cortex function during imagery of dominant hand movement. The aim of this study was to examine the modulation of excitability in the dominant and non-dominant corticomotor pathways during kinesthetic motor imagery of unimanual and bimanual movement. Transcranial magnetic stimulation (TMS) was applied over the contralateral motor cortex (M1) to elicit motor-evoked potentials (MEPs) in the abductor pollicis brevis (APB) and abductor digiti minimi (ADM) muscles of each hand, in two separate sessions. Transcutaneous electrical stimuli were also delivered to the median nerve at each wrist, to elicit F-waves from APB. Fifteen right-handed volunteers imagined unimanual and bimanual phasic thumb movements, paced with a 1-Hz auditory metronome. Stimuli were delivered at rest, and either 50 ms before (ON phase), or 450 ms after (OFF phase), the metronome beeps. Significant MEP amplitude facilitation occurred only in right APB, during the ON phase of motor imagery of the right hand and both hands. Significant temporal modulation of right APB MEP amplitude was observed during motor imagery of right, left and bimanual performance. F-wave persistence and amplitude were unaffected by imagery. These results demonstrate that the motor imagery is lateralized to the left (dominant) hemisphere, which is engaged by imagery of each hand separately, and bimanual imagery. This finding has implications for the use of motor imagery in rehabilitation.

Background. Somatosensory stimulation (SS) is a potential adjuvant to stroke rehabilitation, but the effect on function needs further investigation. Objective. To explore the effect of combining SS with task-specific training (TST) on upper limb function and arm use in chronic stroke survivors and determine underlying mechanisms. Methods. In this double-blinded randomized controlled trial (ISRCTN 05542931), 33 patients (mean 37.7 months poststroke) were block randomized to 2 groups: active or sham SS. They received 12 sessions of 2 hours of SS (active or sham) to all 3 upper limb nerves immediately before 30 minutes of TST. The primary outcome was the Action Research Arm Test (ARAT) score. Secondary outcomes were time to perform the ARAT, Fugl-Meyer Assessment score (FM), Motor Activity Log (MAL), and Goal Attainment Scale (GAS). Underlying mechanisms were explored using transcranial magnetic stimulation stimulus–response curves and intracortical inhibition. Outcomes were assessed at baseline, immediately following the intervention (mean 2 days), and 3 and 6 months (mean 96 and 190 days) after the intervention. Results. The active group (n = 16) demonstrated greater improvement in ARAT score and time immediately postintervention (between-group difference; P < .05), but not at 3- or 6-month follow-ups ( P > .2). Within-group improvements were seen for both groups for ARAT and GAS, but for the active group only for FM and MAL ( P < .05). Corticospinal excitability did not change. Conclusions. Long-lasting improvements in upper limb function were observed following TST. Additional benefit of SS was seen immediately post treatment, but did not persist and the underlying mechanisms remain unclear.

The aim of this study was to investigate the involvement of the parietal cortex during motor imagery (MI). In experiment one, participants imagined a sequence of upper limb movements during FMRI scanning. Statistical parametric mapping revealed a network of activation consistent with previous MI research, including activation in right and left inferior and superior parietal cortex. In experiment two, participants imagined a sequence of upper limb movements while real or sham single-pulse TMS was delivered over the scalp area corresponding to each individual’s left or right superior parietal cortex. At the end of each trial, participants moved their upper limbs to the position that would result from executing the sequence of movements. TMS degraded accuracy of MI compared to sham stimulation, and both accuracy and confidence decreased with real and sham stimulation later in the MI sequence. The effects of TMS were similar when delivered to either hemisphere. The results of this study provide evidence of the crucial role of SPL in MI, and may have implications for rehabilitation from brain injury.

Coincident hand and foot movements are more reliably performed in the same direction than in opposite directions. Using transcranial magnetic stimulation (TMS) to assess motor cortex function, we examined the physiological basis of these movements across three novel experiments. Experiment 1 demonstrated that upper limb corticomotor excitability changed in a way that facilitated isodirectional movements of the hand and foot, during phasic and isometric muscle activation conditions. Experiment 2 demonstrated that motor cortex inhibition was modified with active, but not passive, foot movement in a manner that facilitated hand movement in the direction of foot movement. Together, these findings demonstrate that the coupling between motor representations within motor cortex is activity dependent. Because there are no known connections between hand and foot areas within primary motor cortex, experiment 3 used a dual-coil paired-pulse TMS protocol to examine functional connectivity between secondary and primary motor areas during active ankle dorsiflexion and plantarflexion. Dorsal premotor cortex (PMd) and supplementary motor area (SMA) conditioning, but not ventral premotor cortex (PMv) conditioning, produced distinct phases of task-dependent modulation of excitability of forearm representations within primary motor cortex (M1). Networks involving PMd–M1 facilitate isodirectional movements of hand and foot, whereas networks involving SMA–M1 facilitate corticomotor pathways nonspecifically, which may help to stabilize posture during interlimb coordination. These results may have implications for targeted neurorehabilitation after stroke.

Purpose: To determine whether a model of two subtypes of yips is supported by evidence from a range of physiological, behavioral, and psychological measures. Methods: Fifteen golfers who experience yips symptoms while putting (mean age 58.1 yr, SD 13.6 yr), and nine golfers with no yips symptoms (mean age 39.6 yr, SD 19.3 yr) were recruited. Participants completed a golf history questionnaire to determine their playing experience and the nature of any yips symptoms experienced. In experiment 1, participants performed a putting task while electromyographic data were recorded from the forearm flexors and extensors and biceps brachii, bilaterally. The task was performed in two sessions, under low-pressure and high-pressure experimental conditions. The high-pressure condition was intended to increase anxiety through the use of a monetary incentive, video-taping of performance, and the presence of a confederate who provided negative feedback. Participants' state of anxiety was assessed using a questionnaire before each of the experimental sessions. In experiment 2, participants completed a task that required the inhibition of an anticipated response. Their accuracy and ability to inhibit their response was determined. Results: The golfers who experienced yips could be categorized according to whether they reported mainly movement-related symptoms (Type I) or anxiety-related symptoms (Type II). The Type I group exhibited greater muscle activity during putting and greater errors and less inhibition of the anticipated response task. The Type II group exhibited greater changes in cognitive anxiety and normal performance of the anticipated response task. Conclusion: This study provides evidence in support of two yips subtypes. Type I is related to impaired movement initiation and execution, whereas Type II is related to performance anxiety.

Objective To explore potential predictors of self-reported paretic arm use at baseline and after task-specific training (TST) in survivors of stroke. Design Data were obtained from a randomized controlled trial of somatosensory stimulation and upper limb TST in chronic stroke. Setting University laboratory. Participants Chronic (≥3mo) survivors of stroke (N=33; mean age, 62y; mean stroke duration, 38mo). Interventions Participants received 12 sessions of TST preceded by either active (n=16) or sham (n=17) somatosensory stimulation to all 3 peripheral nerves. Main Outcome Measures Demographic and clinical characteristics were entered stepwise into multiple linear regression analyses to determine the factors that best predict baseline Motor Activity Log (MAL) amount of use rating and change 3 months after TST. Results The Action Research Arm Test (ARAT) score predicted the amount of use at baseline (R2=.47, P