Neurophysiology of motor skill learning in chronic stroke

ObjectiveMotor learning is relevant in chronic stroke for acquiring compensatory strategies to motor control deficits. However, the neurophysiological mechanisms underlying motor skill acquisition with the paretic upper limb have received little systematic investigation. The aim of this study was to assess the modulation of corticomotor excitability and intracortical inhibition within ipsilesional primary motor cortex (M1) during motor skill learning.MethodsTen people at the chronic stage after stroke and twelve healthy controls trained on a sequential visuomotor isometric wrist extension task. Skill was quantified before, immediately after, 24 hours and 7 days post-training. Transcranial magnetic stimulation was used to examine corticomotor excitability and short- and long-interval intracortical inhibition (SICI and LICI) pre- and post-training.ResultsThe patient group exhibited successful skill acquisition and retention, although absolute skill level was lower compared with controls. In contrast to controls, patients’ ipsilesional corticomotor excitability was not modulated during skill acquisition, which may be attributed to excessive ipsilesional LICI relative to controls. SICI decreased after training for both patient and control groups.ConclusionsOur findings indicate distinct inhibitory networks within M1 that may be relevant for motor learning after stroke.SignificanceThese findings have potential clinical relevance for neurorehabilitation adjuvants aimed at augmenting the recovery of motor function.     

神经干刺激疗法配合言语康复训练在卒中后失语症患者中的应用

目的 评价神经干刺激疗法配合言语康复训练在卒中后失语症患者中的应用效果。方法 选择我院康复科2016年3月～2018年10月收治的卒中后失语症患者82例作为本次研究对象,采用随机数字表法将患者随机分为对照组(n=41)与观察组(n=41)。两组患者均开展常规治疗,对照组在此基础上开展言语康复训练,观察组开展神经干刺激疗法配合言语康复训练,对比两组患者治疗后临床效果,治疗前后语言功能情况。结果 两组患者治疗前后语言功能情况:治疗前,两组患者语言功能自发谈话、理解、复述、命名、阅读、书写6项评分比较,差异均无统计学意义(P0.05),治疗后两组6项评分均明显上升,观察组高于对照组,差异均有统计学意义(P0.05);临床效果:观察组治疗总有效率为95.12%,明显高于对照组的80.49%,差异有统计学意义(P0.05)。结论 神经干刺激疗法配合言语康复训练在卒中后失语症患者中应用效果肯定,能够提升患者口语表达能力、改善理解障碍与复述能力、提高文字阅读能力及书写准确率。     

针灸治疗对脑卒中偏瘫患者总有效率的影响

目的:探究针灸治疗对脑卒中偏瘫患者总有效率的影响。方法:将2017年1月-2018年12月在我院接受治疗的58例脑卒中偏瘫患者作为研究对象,随机数字表法分为观察组与对照组,每组29例,分别给予针灸治疗与常规治疗,对两组患者治疗前后神经功能缺损评分(Neurological Impairment Score Scale,NIHSS)、日常生活能力(Barthel指数)以及临床治疗效果进行综合评价。结果:观察组患者治疗后的NIHSS评分明显降低,Barthel指数提高,与对照组比较差异有统计学意义(P<0.05);观察组患者治疗后总有效率与对照组比较,差异有统计学意义(P<0.05)。结论:针灸治疗脑卒中偏瘫患者,能够促进神经功能改善,提高患者日常生活能力,效果显著,值得推广应用。     

Delayed diapedesis of CD8 T cells contributes to long-term pathology after ischemic stroke in male mice

ObjectiveStroke is a debilitating disorder with significant annual mortality and morbidity rates worldwide. Immune cells are recruited to the injured brain within hours after stroke onset and can exhibit either protective or detrimental effects on recovery. However, immune cells, including CD8 T cells, persist in the injured brain for weeks, suggesting a longer-term role for the adaptive immune system during functional recovery. The aim of this study was to determine if the delayed secondary diapedesis of CD8 T cells into the ischemic brain negatively impacts functional recovery after transient ischemic stroke in male mice.ResultsMice exhibited an increased number of leukocytes in the ipsilesional hemispheres at 14 days (3-fold; p < 0.001) and 30 days (2.2-fold; p = 0.02) after transient middle cerebral artery occlusion (tMCAo) compared to 8 days post-tMCAo, at which time acute neuroinflammation predominantly resolves. Moreover, mice with higher ipsilesional CD8 T cells at 30 days (R² = 0.52, p < 0.01) exhibited worse functional recovery. To confirm a detrimental role of chronic CD8 T cell diapedesis on recovery, peripheral CD8 T cells were depleted beginning 10 days post-tMCAo. Delayed CD8 T cell depletion improved motor recovery on the rotarod (F_(1,28) = 4.264; p = 0.048) compared to isotype control-treated mice. CD8 T cell-depleted mice also exhibited 2-fold (p < 0.001) reduced leukocyte infiltration at 30 days post-tMCAo. Specifically, macrophage, neutrophil, and CD4 T cell numbers were reduced in the ipsilesional hemisphere of the CD8 T cell-depleted mice independent of inflammatory status of the post-stroke CNS (e.g. microglial phenotype and cytokine production). RNAseq identified a unique profile for brain infiltrating CD8 T cells at 30 days post-tMCAo, with 46 genes differentially expressed relative to CD8 T cells at 3 days post-tMCAo.ConclusionOur data reveal a role for CD8 T cells in the chronic phase post-stroke that can be therapeutically targeted. We demonstrate long-term CD8 T cell recruitment into the ipsilesional hemisphere that affects both immune cell numbers present in the injured brain and functional recovery through one month after stroke onset.     

Central auditory processing: behavioral and electrophysiological assessment of children and adolescents diagnosed with stroke

IntroductionCentral auditory processing refers to the efficiency and effectiveness with which the central nervous system uses auditory information: it may be altered in neurological disorders and brain injuries, such as strokes. However, despite evidence of probable alterations in the pediatric population, functional abilities and post-stroke limitations are still not well documented in the literature.ObjectiveTo analyze the findings of the electrophysiological and behavioral evaluations of central auditory processing of children and adolescents diagnosed with stroke from a reference outpatient clinic, as well as to investigate possible associations with the variables: type and location of the stroke and age group.MethodsThe present study is characterized as comparative cross-sectional. The sample, for convenience, included individuals aged 7–18 years divided into two groups: study group, composed of individuals with a diagnosis of stroke, and control group, composed of individuals with typical development. The evaluation consisted of the following procedures: anamnesis, basic audiological evaluation, behavioral evaluation of the auditory processing disorder (dichotic digit test, dichotic consonant-vowel, synthetic sentence identification/pediatric speech intelligibility, gaps in noise, pitch pattern sequence, masking level difference), and electrophysiological evaluation (P300 and mismatch negativity).ResultsNineteen children and adolescents were included in the study group. The control group was composed of 19 children and adolescents with typical development. In the comparison between the groups, a worse performance is observed for the study group in all the evaluated tests, behavioral and electrophysiological. In the behavioral evaluation of central auditory processing, there was a statistical difference for all tests, except for masking level difference and dichotic digit test, binaural separation step on the left. In the electrophysiological evaluation, there was a statistical difference in the latency of mismatch negativity and P300. No associations were found between the behavioral and electrophysiological findings and the location of the stroke and age group variables.ConclusionChildren and adolescents diagnosed with stroke present a worse performance in the electrophysiological and behavioral evaluations of central auditory processing when compared to a control group.     

Surviving a stroke in South Africa: outcomes of home-based care in a low-resource rural setting

Background: Little is known of stroke outcomes in low- and middle-income countries with limited formal stroke rehabilitation services and of homebased-stroke services delivered within the primary health care (PHC) context by community health workers (CHWs).

Objectives: To describe and analyze the outcomes of patients with stroke from a rural PHC setting in the Western Cape, South Africa.

Methods: In a longitudinal survey, 93 stroke patients, referred to home and community-based care services (HCBC) between June 2015 and December 2017, were assessed at baseline, one month and three months. Changes in function (Barthel Index (BI)), caregiver strain (Caregiver Strain Index (CSI)), impact of environmental factors and satisfaction with stroke care were measured.

Results: HCBC was delayed, fragmented and brief (median session duration 20 minutes (IQR 15.0–30.0)). Although function improved significantly, dependence remained high: median BI score changed from 40.0 (IQR 15.0–70.0) to 62.5 (IQR 30.0–81.25) (p = .019). A third (33.0% (30/91)) of caregivers initially experienced strain and the median CSI score remained 3.0 (IQR 0.0–7.0) (p = .672). Overall, patient and caregiver satisfaction with HCBC was low with only 46.9% (31/66) of caregivers and 17.4% (12/69) of patients satisfied with all aspects of care. Only 47.6% of assistive product needs were met. Environmental factors negatively impacted on patient function and caregiving.

Conclusions: Clinical practice pathways and referral guidelines should be developed for the HCBC platform. Specific training of CHWs, focusing on how to educate, support and train family caregivers, provide assistive devices and refer to health services is needed.     

Depression treatment use among stroke individuals with depression: A cross-sectional analysis of the Medical Expenditure Panel Survey

BackgroundDepression is the most prevalent psychiatric comorbidity among stroke individuals. Despite the effectiveness of antidepressants and psychotherapy, data on the use of these treatments among stroke survivors is limited.ObjectiveThe main objective of this study was to document prevalence of antidepressant use, types of antidepressants utilized, and adherence to antidepressants among stroke individuals.MethodsRetrospective, cross-sectional data obtained from the Medical Expenditure Panel Surveys (MEPS), for the years 2011, 2013 and 2015, was utilized for this study. Treatment for depression was categorized into three mutually exclusive categories: 1) antidepressants only, 2) antidepressants and psychotherapy (combination), and 3) No treatment. Adherence to antidepressants was measured using the Proportion of Days Covered (PDC) ratio. Adherence between antidepressant only and combination therapy group was compared using Student's t-test. A multinomial logistic regression analysis was used to further examine the association between patient characteristics and likelihood of receiving depression treatment.ResultsA total of 759 stroke individuals with comorbid depression were identified. Of these, 51.2% utilized only antidepressants, 12.6% utilized a combination treatment of antidepressants and psychotherapy and 31.7% did not receive treatment for depression. Selective Serotonin Reuptake Inhibitors (SSRI's) was the most commonly used antidepressants in the stroke population. Males (P = 0.04), age group of 40–64 years (P < 0.001), and African Americans (P = 0.02) constituted for the highest proportions of untreated stroke survivors. Among treated stroke individuals, adherence was higher for combination therapy users compared to those using antidepressants only (mean PDC = 65.8 ± 6.89 and 57.6 ± 3.74, respectively).ConclusionAlmost 70% of stroke individuals received some form of treatment for depression and several patient-related factors (gender, age, race, marital status, and comorbidity burden) were associated with the utilization of depression treatment. Future researchers need to investigate the factors responsible for lack of depression treatment in stroke individuals and policy makers should aim for a more patient centered care.