1
|
Jagadish A, Natarajan M, Adhia DB, Kuppuswamy A, Guddattu V, Solomon JM. Effect of high-definition transcranial direct current stimulation among late-subacute and chronic stroke survivors with fatigue: A randomized-controlled crossover trial protocol. MethodsX 2024; 12:102629. [PMID: 38435639 PMCID: PMC10907195 DOI: 10.1016/j.mex.2024.102629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Accepted: 02/22/2024] [Indexed: 03/05/2024] Open
Abstract
Post-stroke fatigue (PSF) is a commonly overlooked symptom that impacts daily functioning and quality of life. It is caused by altered functional connectivity within the brain networks, which can potentially be influenced by neuromodulation. Multiple cortical regions have been targeted to reduce PSF, but the most efficient ones remain uncertain. Therefore, we aim to identify the most appropriate cortical stimulation site to reduce PSF. Twenty participants with PSF will be included in this cross-over trial. Each participant will receive one session of active anodal high definition- transcranial direct current stimulation (HD-tDCS) over three different cortical areas and one session of sham tDCS in a cross-over manner, with a two-week of washout period in between. Pre- and post- fatigue will be assessed using Fatigue Severity Scale and fatigability using electromyography by determining the time to task failure. Resting-state electroencephalography will be performed before and after each stimulation session to determine the functional connectivity of the cortical areas stimulated.
Collapse
Affiliation(s)
- Akhila Jagadish
- Department of Physiotherapy, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India
- Centre for Comprehensive Stroke Rehabilitation and Research (CCSRR), Manipal Academy of Higher Education, Manipal, Karnataka 576104, India
| | - Manikandan Natarajan
- Department of Physiotherapy, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India
- Centre for Comprehensive Stroke Rehabilitation and Research (CCSRR), Manipal Academy of Higher Education, Manipal, Karnataka 576104, India
| | - Divya Bharatkumar Adhia
- Department of Surgical Sciences, Dunedin School of Medicine, University of Otago, Dunedin 9013, New Zealand
| | | | - Vasudeva Guddattu
- Department of Data Science, Prasanna School of Public Health, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India
| | - John M. Solomon
- Department of Physiotherapy, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India
- Centre for Comprehensive Stroke Rehabilitation and Research (CCSRR), Manipal Academy of Higher Education, Manipal, Karnataka 576104, India
| |
Collapse
|
2
|
De Doncker W, Kuppuswamy A. Influence of Perceptual Load on Attentional Orienting in Post-Stroke Fatigue: A Study of Auditory Evoked Potentials. Neurorehabil Neural Repair 2024; 38:257-267. [PMID: 38339993 PMCID: PMC10976458 DOI: 10.1177/15459683241230030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2024]
Abstract
OBJECTIVE Increasing perceptual load alters behavioral outcomes in post-stroke fatigue (PSF). While the effect of perceptual load on top-down attentional processing is known, here we investigate if increasing perceptual load modulates bottom-up attentional processing in a fatigue dependent manner. METHODS In this cross-sectional observational study, in 29 first-time stroke survivors with no clinical depression, an auditory oddball task consisting of target, standard, and novel tones was performed in conditions of low and high perceptual load. Electroencephalography was used to measure auditory evoked potentials. Perceived effort was rated using the visual analog scale at regular intervals during the experiment. Fatigue was measured using the fatigue severity scale. The effect of fatigue and perceptual load on behavior (response time, accuracy, and effort rating) and auditory evoked potentials (amplitude and latency) was examined using mixed model ananlysis of variances (ANOVA). RESULTS Response time was prolonged with greater perceptual load and fatigue. There was no effect of load or fatigue on accuracy. Greater effort was reported with higher perceptual load both in high and low fatigue. p300a amplitude of auditory evoked potentials (AEP) for novel stimuli was attenuated in high fatigue with increasing load when compared to low fatigue. Latency of p300a was longer in low fatigue with increasing load when compared to high fatigue. There were no effects on p300b components, with smaller N100 in high load conditions. INTERPRETATION High fatigue specific modulation of p300a component of AEP with increasing load is indicative of distractor driven alteration in orienting response, suggestive of compromise in bottom-up selective attention in PSF.
Collapse
Affiliation(s)
- William De Doncker
- Department of Clinical and Movement Neuroscience, Institute of Neurology, UCL, London, UK
| | - Annapoorna Kuppuswamy
- Department of Clinical and Movement Neuroscience, Institute of Neurology, UCL, London, UK
- Department of Biomedical Sciences, University of Leeds, Leeds, UK
| |
Collapse
|
3
|
De Doncker W, Kuppuswamy A. Lesioned hemisphere-specific phenotypes of post-stroke fatigue emerge from motor and mood characteristics in chronic stroke. Eur J Neurol 2024; 31:e16170. [PMID: 38069662 DOI: 10.1111/ene.16170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 11/03/2023] [Accepted: 11/14/2023] [Indexed: 02/09/2024]
Abstract
BACKGROUND AND PURPOSE Post-stroke fatigue commonly presents alongside several comorbidities. The interaction between comorbidities and their relationship to fatigue is not known. In this study, we focus on physical and mood comorbidities, alongside lesion characteristics. We predict the emergence of distinct fatigue phenotypes with distinguishable physical and mood characteristics. METHODS In this cross-sectional observational study, in 94 first time, non-depressed, moderate to minimally impaired chronic stroke survivors, the relationship between measures of motor function (grip strength, nine-hole peg test time), motor cortical excitability (resting motor threshold), Hospital Anxiety and Depression Scale and Fatigue Severity Scale-7 (FSS-7) scores, age, gender and side of stroke was established using Spearman's rank correlation. Mood and motor variables were then entered into a k-means clustering algorithm to identify the number of unique clusters, if any. Post hoc pairwise comparisons followed by corrections for multiple comparisons were performed to characterize differences among clusters in the variables included in k-means clustering. RESULTS Clustering analysis revealed a four-cluster model to be the best model (average silhouette score of 0.311). There was no significant difference in FSS-7 scores among the four high-fatigue clusters. Two clusters consisted of only left-hemisphere strokes, and the remaining two were exclusively right-hemisphere strokes. Factors that differentiated hemisphere-specific clusters were the level of depressive symptoms and anxiety. Motor characteristics distinguished the low-depressive left-hemisphere from the right-hemisphere clusters. CONCLUSION The significant differences in side of stroke and the differential relationship between mood and motor function in the four clusters reveal the heterogenous nature of post-stroke fatigue, which is amenable to categorization. Such categorization is critical to an understanding of the interactions between post-stroke fatigue and its presenting comorbid deficits, with significant implications for the development of context-/category-specific interventions.
Collapse
Affiliation(s)
- William De Doncker
- Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, London, UK
| | - Annapoorna Kuppuswamy
- Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, London, UK
- Department of Biomedical Sciences, University of Leeds, Leeds, UK
| |
Collapse
|
4
|
English C, Simpson DB, Billinger SA, Churilov L, Coupland KG, Drummond A, Kuppuswamy A, Kutlubaev MA, Lerdal A, Mahmood A, Moseley GL, Pittman QJ, Riley EA, Sutherland BA, Wong CHY, Corbett D, Mead G. A roadmap for research in post-stroke fatigue: Consensus-based core recommendations from the third Stroke Recovery and Rehabilitation Roundtable. Int J Stroke 2024; 19:133-144. [PMID: 37424273 PMCID: PMC10811972 DOI: 10.1177/17474930231189135] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 06/27/2023] [Indexed: 07/11/2023]
Abstract
RATIONALE Fatigue affects almost half of all people living with stroke. Stroke survivors rank understanding fatigue and how to reduce it as one of the highest research priorities. METHODS We convened an interdisciplinary, international group of clinical and pre-clinical researchers and lived experience experts. We identified four priority areas: (1) best measurement tools for research, (2) clinical identification of fatigue and potentially modifiable causes, (3) promising interventions and recommendations for future trials, and (4) possible biological mechanisms of fatigue. Cross-cutting themes were aphasia and the voice of people with lived experience. Working parties were formed and structured consensus building processes were followed. RESULTS We present 20 recommendations covering outcome measures for research, development, and testing of new interventions and priority areas for future research on the biology of post-stroke fatigue. We developed and recommend the use of the Stroke Fatigue Clinical Assessment Tool. CONCLUSIONS By synthesizing current knowledge in post-stroke fatigue across clinical and pre-clinical fields, our work provides a roadmap for future research into post-stroke fatigue.
Collapse
Affiliation(s)
- Coralie English
- School of Health Sciences, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, NSW, Australia
- Heart and Stroke Program, Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - Dawn B Simpson
- School of Health Sciences, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, NSW, Australia
- Heart and Stroke Program, Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - Sandra A Billinger
- Department of Neurology, University of Kansas Medical Centre, University of Kansas Alzheimer’s Disease Research Centre, Kansas City, KS, USA
| | - Leonid Churilov
- Department of Medicine (RMH), University of Melbourne, Heidelberg, VIC, Australia
| | - Kirsten G Coupland
- Heart and Stroke Program, Hunter Medical Research Institute, Newcastle, NSW, Australia
- School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, NSW, Australia
| | - Avril Drummond
- School of Health Sciences, University of Nottingham, Nottingham, UK
| | | | | | - Anners Lerdal
- Department of Interdisciplinary Health Sciences, Institute of Health and Society, Faculty of Medicine, University of Oslo, Oslo, Norway
- Research Department, Lovisenberg Diaconal Hospital, Oslo, Norway
| | - Amreen Mahmood
- Faculty of Health, Health and Education, Manchester Metropolitan University, Manchester, UK
| | - G Lorimer Moseley
- IIMPACT in Health, University of South Australia, Adelaide, SA, Australia
| | - Quentin J Pittman
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Ellyn A Riley
- Department of Communication Sciences and Disorders, Syracuse University, Syracuse, NY, USA
| | - Brad A Sutherland
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, TAS, Australia
| | - Connie HY Wong
- Centre for Inflammatory Diseases, Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, VIC, Australia
| | - Dale Corbett
- Department of Cellular and Molecular Medicine, University of Ottawa Roger Guindon Hall, Ottawa, ON, Canada
| | - Gillian Mead
- Ageing and Health, Usher Institute, University of Edinburgh, Edinburgh, UK
| |
Collapse
|
5
|
Kuppuswamy A, Billinger S, Coupland KG, English C, Kutlubaev MA, Moseley L, Pittman QJ, Simpson DB, Sutherland BA, Wong C, Corbett D. Mechanisms of Post-Stroke Fatigue: A Follow-Up From the Third Stroke Recovery and Rehabilitation Roundtable. Neurorehabil Neural Repair 2024; 38:52-61. [PMID: 38156702 PMCID: PMC10798014 DOI: 10.1177/15459683231219266] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
BACKGROUND Post-stroke fatigue (PSF) is a significant and highly prevalent symptom, whose mechanisms are poorly understood. The third Stroke Recovery and Rehabilitation Roundtable paper on PSF focussed primarily on defining and measuring PSF while mechanisms were briefly discussed. This companion paper to the main paper is aimed at elaborating possible mechanisms of PSF. METHODS This paper reviews the available evidence that potentially explains the pathophysiology of PSF and draws parallels from fatigue literature in other conditions. We start by proposing a case for phenotyping PSF based on structural, functional, and behavioral characteristics of PSF. This is followed by discussion of a potentially significant role of early inflammation in the development of fatigue, specifically the impact of low-grade inflammation and its long-term systemic effects resulting in PSF. Of the many neurotransmitter systems in the brain, the dopaminergic systems have the most evidence for a role in PSF, along with a role in sensorimotor processing. Sensorimotor neural network dynamics are compromised as highlighted by evidence from both neurostimulation and neuromodulation studies. The double-edged sword effect of exercise on PSF provides further insight into how PSF might emerge and the importance of carefully titrating interventional paradigms. CONCLUSION The paper concludes by synthesizing the presented evidence into a unifying model of fatigue which distinguishes between factors that pre-dispose, precipitate, and perpetuate PSF. This framework will help guide new research into the biological mechanisms of PSF which is a necessary prerequisite for developing treatments to mitigate the debilitating effects of post-stroke fatigue.
Collapse
Affiliation(s)
- Annapoorna Kuppuswamy
- Queen Square Institute of Neurology, University College London, London, UK
- Department of Biomedical Sciences, University of Leeds, Leeds, UK
| | - Sandra Billinger
- Department of Neurology, University of Kansas Medical Center, University of Kansas Alzheimer’s Disease Research Center, Fairway, KS, MO, USA
| | - Kirsten G. Coupland
- School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Australia Heart and Stroke Program, Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - Coralie English
- School of Health Sciences, College of Health, Medicine and Wellbeing, University of Newcastle, Australia Heart and Stroke Program, Hunter Medical Research Institute, Newcastle, NSW, Australia
| | | | - Lorimer Moseley
- IIMPACT in Health, University of South Australia, Adelaide, SA, Australia
| | - Quentin J. Pittman
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Dawn B. Simpson
- School of Health Sciences, College of Health, Medicine and Wellbeing, University of Newcastle, Australia Heart and Stroke Program, Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - Brad A. Sutherland
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, TS, Australia
| | - Connie Wong
- Centre for Inflammatory Diseases, Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, VIC, Australia
| | - Dale Corbett
- Department of Cellular and Molecular Medicine, University of Ottawa Brain and Mind Institute, University of Ottawa, Ottawa, ON, Canada
| |
Collapse
|
6
|
English C, Simpson DB, Billinger SA, Churilov L, Coupland KG, Drummond A, Kuppuswamy A, Kutlubaev MA, Lerdal A, Mahmood A, Moseley GL, Pittman QJ, Riley EA, Sutherland BA, Wong CHY, Corbett D, Mead G. A roadmap for research in post-stroke fatigue: Consensus-based core recommendations from the third Stroke Recovery and Rehabilitation Roundtable. Neurorehabil Neural Repair 2024; 38:7-18. [PMID: 37837346 PMCID: PMC10798034 DOI: 10.1177/15459683231209170] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2023]
Abstract
RATIONALE Fatigue affects almost half of all people living with stroke. Stroke survivors rank understanding fatigue and how to reduce it as one of the highest research priorities. METHODS We convened an interdisciplinary, international group of clinical and pre-clinical researchers and lived experience experts. We identified four priority areas: (1) best measurement tools for research, (2) clinical identification of fatigue and potentially modifiable causes, (3) promising interventions and recommendations for future trials, and (4) possible biological mechanisms of fatigue. Cross-cutting themes were aphasia and the voice of people with lived experience. Working parties were formed and structured consensus building processes were followed. RESULTS We present 20 recommendations covering outcome measures for research, development, and testing of new interventions and priority areas for future research on the biology of post-stroke fatigue. We developed and recommend the use of the Stroke Fatigue Clinical Assessment Tool. CONCLUSIONS By synthesizing current knowledge in post-stroke fatigue across clinical and pre-clinical fields, our work provides a roadmap for future research into post-stroke fatigue.
Collapse
Affiliation(s)
- Coralie English
- School of Health Sciences, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, NSW, Australia
- Heart and Stroke Program, Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - Dawn B Simpson
- School of Health Sciences, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, NSW, Australia
- Heart and Stroke Program, Hunter Medical Research Institute, Newcastle, NSW, Australia
| | - Sandra A Billinger
- Department of Neurology, University of Kansas Medical Centre, University of Kansas Alzheimer’s Disease Research Centre, Kansas City, KS, USA
| | - Leonid Churilov
- Department of Medicine (RMH), University of Melbourne, Heidelberg, VIC, Australia
| | - Kirsten G Coupland
- Heart and Stroke Program, Hunter Medical Research Institute, Newcastle, NSW, Australia
- School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, NSW, Australia
| | - Avril Drummond
- School of Health Sciences, University of Nottingham, Nottingham, UK
| | | | | | - Anners Lerdal
- Department of Interdisciplinary Health Sciences, Institute of Health and Society, Faculty of Medicine, University of Oslo, Oslo, Norway
- Research Department, Lovisenberg Diaconal Hospital, Oslo, Norway
| | - Amreen Mahmood
- Faculty of Health, Health and Education, Manchester Metropolitan University, Manchester, UK
| | - G Lorimer Moseley
- IIMPACT in Health, University of South Australia, Adelaide, SA, Australia
| | - Quentin J Pittman
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Ellyn A Riley
- Department of Communication Sciences and Disorders, Syracuse University, Syracuse, NY, USA
| | - Brad A Sutherland
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, TAS, Australia
| | - Connie HY Wong
- Centre for Inflammatory Diseases, Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, VIC, Australia
| | - Dale Corbett
- Department of Cellular and Molecular Medicine, University of Ottawa Roger Guindon Hall, Ottawa, ON, Canada
| | - Gillian Mead
- Ageing and Health, Usher Institute, University of Edinburgh, Edinburgh, UK
| |
Collapse
|
7
|
Tankisi H, Versace V, Kuppuswamy A, Cole J. The role of clinical neurophysiology in the definition and assessment of fatigue and fatigability. Clin Neurophysiol Pract 2023; 9:39-50. [PMID: 38274859 PMCID: PMC10808861 DOI: 10.1016/j.cnp.2023.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 11/24/2023] [Accepted: 12/07/2023] [Indexed: 01/27/2024] Open
Abstract
Though a common symptom, fatigue is difficult to define and investigate, occurs in a wide variety of neurological and systemic disorders, with differing pathological causes. It is also often accompanied by a psychological component. As a symptom of long-term COVID-19 it has gained more attention. In this review, we begin by differentiating fatigue, a perception, from fatigability, quantifiable through biomarkers. Central and peripheral nervous system and muscle disorders associated with these are summarised. We provide a comprehensive and objective framework to help identify potential causes of fatigue and fatigability in a given disease condition. It also considers the effectiveness of neurophysiological tests as objective biomarkers for its assessment. Among these, twitch interpolation, motor cortex stimulation, electroencephalography and magnetencephalography, and readiness potentials will be described for the assessment of central fatigability, and surface and needle electromyography (EMG), single fibre EMG and nerve conduction studies for the assessment of peripheral fatigability. The purpose of this review is to guide clinicians in how to approach fatigue, and fatigability, and to suggest that neurophysiological tests may allow an understanding of their origin and interactions. In this way, their differing types and origins, and hence their possible differing treatments, may also be defined more clearly.
Collapse
Affiliation(s)
- Hatice Tankisi
- Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus, Denmark
- Institute of Clinical Medicine, Aarhus University, Denmark
| | - Viviana Versace
- Department of Neurorehabilitation, Hospital of Vipiteno (SABES-ASDAA), Teaching Hospital of the Paracelsus Medical Private University (PMU), Vipiteno-Sterzing, Italy
| | - Annapoorna Kuppuswamy
- Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, WC1N 3BG London, UK
- Department of Biomedical Sciences, University of Leeds, UK
| | - Jonathan Cole
- Clinical Neurophysiology, University Hospitals Dorset (Poole), UK
- University of Bournemouth, Poole, UK
| |
Collapse
|
8
|
Kusec A, Milosevich E, Williams OA, Chiu EG, Watson P, Carrick C, Drozdowska BA, Dillon A, Jennings T, Anderson B, Dawes H, Thomas S, Kuppuswamy A, Pendlebury ST, Quinn TJ, Demeyere N. Long-term psychological outcomes following stroke: the OX-CHRONIC study. BMC Neurol 2023; 23:426. [PMID: 38036966 PMCID: PMC10688008 DOI: 10.1186/s12883-023-03463-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 11/10/2023] [Indexed: 12/02/2023] Open
Abstract
BACKGROUND Stroke survivors rate longer-term (> 2 years) psychological recovery as their top priority, but data on how frequently psychological consequences occur is lacking. Prevalence of cognitive impairment, depression/anxiety, fatigue, apathy and related psychological outcomes, and whether rates are stable in long-term stroke, is unknown. METHODS N = 105 long-term stroke survivors (M [SD] age = 72.92 [13.01]; M [SD] acute NIH Stroke Severity Score = 7.39 [6.25]; 59.0% Male; M [SD] years post-stroke = 4.57 [2.12]) were recruited (potential N = 208). Participants completed 3 remote assessments, including a comprehensive set of standardized cognitive neuropsychological tests comprising domains of memory, attention, language, and executive function, and questionnaires on emotional distress, fatigue, apathy and other psychological outcomes. Ninety participants were re-assessed one year later. Stability of outcomes was assessed by Cohen's d effect size estimates and percent Minimal Clinically Important Difference changes between time points. RESULTS On the Montreal Cognitive Assessment 65.3% scored < 26. On the Oxford Cognitive Screen 45.9% had at least one cognitive impairment. Attention (27.1%) and executive function (40%) were most frequently impaired. 23.5% and 22.5% had elevated depression/anxiety respectively. Fatigue (51.4%) and apathy (40.5%) rates remained high, comparable to estimates in the first-year post-stroke. Attention (d = -0.12; 85.8% stable) and depression (d = 0.09, 77.1% stable) were the most stable outcomes. Following alpha-adjustments, only perceptuomotor abilities (d = 0.69; 40.4% decline) and fatigue (d = -0.33; 45.3% decline) worsened over one year. Cognitive impairment, depression/anxiety, fatigue and apathy all correlated with worse quality of life. CONCLUSION Nearly half of participants > 2 years post-event exhibited psychological difficulties including domains of cognition, mood, and fatigue, which impact long-term quality of life. Stroke is a chronic condition with highly prevalent psychological needs, which require monitoring and intervention development.
Collapse
Affiliation(s)
- Andrea Kusec
- Department of Experimental Psychology, University of Oxford, Anna Watts Building, Radcliffe Observatory Quarter, Oxford, UK
| | - Elise Milosevich
- Department of Experimental Psychology, University of Oxford, Anna Watts Building, Radcliffe Observatory Quarter, Oxford, UK
| | - Owen A Williams
- Department of Experimental Psychology, University of Oxford, Anna Watts Building, Radcliffe Observatory Quarter, Oxford, UK
| | - Evangeline G Chiu
- Department of Experimental Psychology, University of Oxford, Anna Watts Building, Radcliffe Observatory Quarter, Oxford, UK
| | - Pippa Watson
- Department of Experimental Psychology, University of Oxford, Anna Watts Building, Radcliffe Observatory Quarter, Oxford, UK
| | - Chloe Carrick
- Department of Experimental Psychology, University of Oxford, Anna Watts Building, Radcliffe Observatory Quarter, Oxford, UK
| | - Bogna A Drozdowska
- School of Cardiovascular & Metabolic Health, University of Glasgow, Glasgow, UK
| | - Avril Dillon
- Department of Health and Life Sciences, Oxford Brookes University, Oxford, UK
| | | | - Bloo Anderson
- Patient and Public Involvement Representative, Oxford, UK
| | - Helen Dawes
- NIHR Exeter Biomedical Research Centre, University of Exeter, Medical School Building, St Luke's Campus, Magdalen Road, Exeter, UK
| | - Shirley Thomas
- School of Medicine, Queen's Medical Centre, University of Nottingham, Nottingham, UK
| | - Annapoorna Kuppuswamy
- Institute of Neurology Department of Clinical and Movement Neurosciences, University College London, 33 Queen Square, London, UK
- Department of Biomedical Sciences, University of Leeds, Leeds, UK
| | - Sarah T Pendlebury
- Wolfson Centre for Prevention of Stroke and Dementia, Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Terence J Quinn
- School of Cardiovascular & Metabolic Health, University of Glasgow, Glasgow, UK
| | - Nele Demeyere
- Department of Experimental Psychology, University of Oxford, Anna Watts Building, Radcliffe Observatory Quarter, Oxford, UK.
- Wolfson Centre for Prevention of Stroke and Dementia, Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK.
| |
Collapse
|
9
|
Wu CH, De Doncker W, Kuppuswamy A. Electroencephalography-Derived Functional Connectivity in Sensorimotor Networks in Post Stroke Fatigue. Brain Topogr 2023; 36:727-735. [PMID: 37328707 PMCID: PMC10415526 DOI: 10.1007/s10548-023-00975-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 06/04/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND Poor suppression of anticipated sensory information from muscle contractions is thought to underlie high fatigue. Such diminished task-related sensory attenuation is reflected in resting state connectivity. Here we test the hypothesis 'altered electroencephalography (EEG)-derived functional connectivity in somatosensory network in the beta band, is a signature of fatigue in post-stroke fatigue'. METHODS In non-depressed, minimally impaired stroke survivors (n = 29), with median disease duration of 5 years, resting state neuronal activity was measured using 64-channel EEG. Graph theory-based network analysis measure of functional connectivity via small-world index (SW) was calculated focusing on right and left motor (Brodmann areas 4, 6, 8, 9, 24 and 32) and sensory (Brodmann areas 1, 2, 3, 5, 7, 40 and 43) networks, in the beta (13-30 Hz) frequency range. Fatigue was measured using Fatigue Severity Scale - FSS (Stroke), with scores of > 4, defined as high fatigue. RESULTS Results confirmed the working hypothesis, with high fatigue stroke survivors showing higher small-worldness in the somatosensory networks when compared to low fatigue. CONCLUSION High levels of small-worldness in somatosensory networks indicates altered processing of somesthetic input. Such altered processing would explain high effort perception within the sensory attenuation model of fatigue.
Collapse
Affiliation(s)
- Chi-Hsu Wu
- Institute of Neurology, University College London, Box 146, 33 Queen Square, London, WC1N 3BG, England
| | - William De Doncker
- Institute of Neurology, University College London, Box 146, 33 Queen Square, London, WC1N 3BG, England
| | - Annapoorna Kuppuswamy
- Institute of Neurology, University College London, Box 146, 33 Queen Square, London, WC1N 3BG, England.
| |
Collapse
|
10
|
Abstract
BACKGROUND Chronic fatigue is a significant symptom in several diseases including traumatic and degenerative neurological disorders. While several studies have investigated the correlates of chronic fatigue, there is as yet no unifying framework to explain chronic fatigue. METHODS In this narrative review, I investigate the role of selective attention in the development of chronic fatigue and discuss results within the framework of the sensory attenuation model of fatigue, which posits that fatigue is the phenomenological output of altered attention to sensory input. Following a short introduction of this framework, I present results from investigations that address attentional mechanisms in fatigue in multiple sclerosis, stroke, traumatic brain injury and Parkinson's disease. RESULTS Attention was quantified in all four disease models using a variety of outcome measures, including behavioural, neurophysiological, structural and functional brain connectivity. The range of measures precluded direct comparison of results across disease conditions; however, in all four disease models there was evidence of poor selective attention that explained levels of chronic fatigue, supporting the sensory attenuation model of fatigue as a disease-independent mechanism of fatigue. Evidence was lacking to draw any conclusions about the direction of causality. CONCLUSION The role of selective attention in development of fatigue is indicated. Future studies must focus on establishing causality and exploring attentional circuitry as a potential therapeutic target.
Collapse
|
11
|
|
12
|
Ondobaka S, De Doncker W, Ward N, Kuppuswamy A. Neural effective connectivity explains subjective fatigue in stroke. Brain 2021; 145:285-294. [PMID: 34791073 PMCID: PMC8967104 DOI: 10.1093/brain/awab287] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 05/20/2021] [Accepted: 06/21/2021] [Indexed: 11/20/2022] Open
Abstract
Persistent fatigue is a major debilitating symptom in many psychiatric and neurological conditions, including stroke. Post-stroke fatigue has been linked to low corticomotor excitability. Yet, it remains elusive as to what the neuronal mechanisms are that underlie motor cortex excitability and chronic persistence of fatigue. In this cross-sectional observational study, in two experiments we examined a total of 59 non-depressed stroke survivors with minimal motoric and cognitive impairments using ‘resting-state’ MRI and single- and paired-pulse transcranial magnetic stimulation. In the first session of Experiment 1, we assessed resting motor thresholds—a typical measure of cortical excitability—by applying transcranial magnetic stimulation to the primary motor cortex (M1) and measuring motor-evoked potentials in the hand affected by stroke. In the second session, we measured their brain activity with resting-state MRI to assess effective connectivity interactions at rest. In Experiment 2 we examined effective inter-hemispheric connectivity in an independent sample of patients using paired-pulse transcranial magnetic stimulation. We also assessed the levels of non-exercise induced, persistent fatigue using Fatigue Severity Scale (FSS-7), a self-report questionnaire that has been widely applied and validated across different conditions. We used spectral dynamic causal modelling in Experiment 1 and paired-pulse transcranial magnetic stimulation in Experiment 2 to characterize how neuronal effective connectivity relates to self-reported post-stroke fatigue. In a multiple regression analysis, we used the balance in inhibitory connectivity between homologue regions in M1 as the main predictor, and have included lesioned hemisphere, resting motor threshold and levels of depression as additional predictors. Our novel index of inter-hemispheric inhibition balance was a significant predictor of post-stroke fatigue in Experiment 1 (β = 1.524, P = 7.56 × 10−5, confidence interval: 0.921 to 2.127) and in Experiment 2 (β = 0.541, P = 0.049, confidence interval: 0.002 to 1.080). In Experiment 2, depression scores and corticospinal excitability, a measure associated with subjective fatigue, also significantly accounted for variability in fatigue. We suggest that the balance in inter-hemispheric inhibitory effects between primary motor regions can explain subjective post-stroke fatigue. Findings provide novel insights into neural mechanisms that underlie persistent fatigue.
Collapse
Affiliation(s)
- Sasha Ondobaka
- CoreMind ltd, NW1 8NP, London, UK.,Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, WC1N 3BG London, UK
| | - William De Doncker
- Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, WC1N 3BG London, UK
| | - Nick Ward
- Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, WC1N 3BG London, UK.,NHNN, University College London, WC1N 3BG London, UK
| | - Annapoorna Kuppuswamy
- Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, WC1N 3BG London, UK
| |
Collapse
|
13
|
Demeyere N, Williams OA, Milosevich E, Chiu EG, Drozdowska BA, Dillon A, Dawes H, Thomas S, Kuppuswamy A, Pendlebury ST, J Quinn T. Long-term psychological consequences of stroke (OX-CHRONIC): A longitudinal study of cognition in relation to mood and fatigue after stroke: Protocol. Eur Stroke J 2021; 6:428-437. [PMID: 35342816 PMCID: PMC8948513 DOI: 10.1177/23969873211046120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 08/25/2021] [Indexed: 12/18/2022] Open
Abstract
Background The long-term psychological consequences of stroke and how cognitive problems change over time after the first-year following stroke remain unclear. Particularly, trajectories of domain-specific and domain-general cognitive functions and how cognition interacts with mood, fatigue and quality of life are not well described. Aims To determine the prevalence, trajectories and wider impact of domain-specific cognitive impairment in long-term stroke survivors, in relation to mood, fatigue and quality of life. Methods Participants who previously took part in the Oxford Cognitive Screening study, completed the 6-month follow-up with cognitive, mood, fatigue and quality of life assessments and agreed to be contacted for future research will be recruited into OX-CHRONIC. The eligible cohort is between 2- and 9-years post-stroke. Cognition will be assessed with a detailed neuropsychological battery, alongside questionnaire measures of mood, fatigue, activities of daily life and quality of life measures at two timepoints, 1 year apart. Additionally, medical records will be accessed to extract further clinical information about the stroke and patients may opt-in to wear an activity monitor for 1 week to provide fine-grained measures of sleep and activity. The study protocol and study materials were approved by the national ethics committee (REC Ref: 19/SC/0520). Planned outputs OX-CHRONIC will provide detailed data on the evolving cognitive profiles of stroke survivors over several years post-stroke. Estimates of long-term prevalence as well as the effect of changes in cognitive profiles on mood, fatigue and quality of life will be examined. This study is funded by a Priority Programme Grant from the Stroke Association (SA PPA 18/100032).
Collapse
Affiliation(s)
- Nele Demeyere
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Owen A Williams
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Elise Milosevich
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Evangeline G Chiu
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Bogna A Drozdowska
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK
| | - Avril Dillon
- Centre for Movement, Occupational and Rehabilitation Sciences, Oxford Institute of Nursing, Midwifery and Allied Health Research, Oxford Brookes University, Oxford, UK
| | - Helen Dawes
- Centre for Movement, Occupational and Rehabilitation Sciences, Oxford Institute of Nursing, Midwifery and Allied Health Research, Oxford Brookes University, Oxford, UK
| | - Shirley Thomas
- School of Medicine, University of Nottingham, Nottingham, UK
| | - Annapoorna Kuppuswamy
- Department of Clinical and Movement Neurosciences, Institute of Neurology, University College London, London, UK
| | - Sarah T Pendlebury
- Wolfson Centre for Prevention of Stroke and Dementia, Wolfson Building, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- NIHR Oxford Biomedical Research Centre and Departments of General (Internal) Medicine and Gerantology, John Radcliffe Hospital, Oxford, UK
| | - Terence J Quinn
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK
| |
Collapse
|
14
|
Abstract
The last decade has seen the emergence of new theoretical frameworks to explain pathological fatigue, a much neglected, yet highly significant symptom across a wide range of diseases. While the new models of fatigue provide new hypotheses to test, they also raise a number of questions. The primary purpose of this essay is to examine the predictions of three recently proposed models of fatigue, the overlap and differences between them, and the evidence from diseases that may lend support to the models of fatigue. I also present expansions for the sensory attenuation model of fatigue. Further questions examined here are the following: What are the neural substrates of fatigue? How can sensory attenuation, which underpins agency also explain fatigue? Are fatigue and agency related?
Collapse
Affiliation(s)
- Annapoorna Kuppuswamy
- Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, London, UK
| |
Collapse
|
15
|
De Doncker W, Brown KE, Kuppuswamy A. Influence of post-stroke fatigue on reaction times and corticospinal excitability during movement preparation. Clin Neurophysiol 2020; 132:191-199. [PMID: 33302061 PMCID: PMC7810236 DOI: 10.1016/j.clinph.2020.11.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 10/07/2020] [Accepted: 11/16/2020] [Indexed: 11/20/2022]
Abstract
Higher the fatigue, lesser the inhibition in movement preparation in stroke survivors. Higher the fatigue, lesser the pre-movement facilitation and slower the reaction times. Poor excitability modulation supports sensory attenuation model of fatigue.
Objectives Reduced corticospinal excitability at rest is associated with post-stroke fatigue (PSF). However, it is not known if corticospinal excitability prior to a movement is also altered in fatigue which may then influence subsequent behaviour. We hypothesized that the levels of PSF can be explained by differences in modulation of corticospinal excitability during movement preparation. Methods 73 stroke survivors performed an auditory reaction time task. Corticospinal excitability was measured using transcranial magnetic stimulation. Fatigue was quantified using the fatigue severity scale. The effect of time and fatigue on corticospinal excitability and reaction time was analysed using a mixed effects model. Results Those with greater levels of PSF showed reduced suppression of corticospinal excitability during movement preparation and increased facilitation immediately prior to movement onset (β = −0.0066, t = −2.22, p = 0.0263). Greater the fatigue, slower the reaction times the closer the stimulation time to movement onset (β = 0.0024, t = 2.47, p = 0.0159). Conclusions Lack of pre-movement modulation of corticospinal excitability in high fatigue may indicate poor sensory processing supporting the sensory attenuation model of fatigue. Significance We take a systems-based approach and investigate the motor system and its role in pathological fatigue allowing us to move towards gaining a mechanistic understanding of chronic pathological fatigue.
Collapse
Affiliation(s)
- William De Doncker
- Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, UK.
| | - Katlyn E Brown
- Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, UK; University of Waterloo, Department of Kinesiology, Faculty of Applied Health Sciences, Waterloo, ON, Canada
| | - Annapoorna Kuppuswamy
- Department of Clinical and Movement Neuroscience, Institute of Neurology, University College London, UK
| |
Collapse
|
16
|
De Doncker W, Charles L, Ondobaka S, Kuppuswamy A. Exploring the relationship between effort perception and poststroke fatigue. Neurology 2020; 95:e3321-e3330. [PMID: 33067406 PMCID: PMC7836654 DOI: 10.1212/wnl.0000000000010985] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 08/03/2020] [Indexed: 11/27/2022] Open
Abstract
Objective To test the hypothesis that poststroke fatigue, a chronic, pathologic fatigue condition, is driven by altered effort perception. Methods Fifty-eight nondepressed, mildly impaired stroke survivors with varying severity of fatigue completed the study. Self-reported fatigue (trait and state), perceived effort (PE; explicit and implicit), and motor performance were measured in a handgrip task. Trait fatigue was measured with the Fatigue Severity Scale-7 and Neurologic Fatigue Index. State fatigue was measured with a visual analog scale (VAS). Length of hold at target force, overshoot above target force, and force variability in handgrip task were measures of motor performance. PE was measured with a VAS (explicit PE) and line length estimation, a novel implicit measure of PE. Results Regression analysis showed that 11.6% of variance in trait fatigue was explained by implicit PE (R = 0.34; p = 0.012). Greater fatigue was related to longer length of hold at target force (R = 0.421, p < 0.001). A backward regression showed that length of hold explained explicit PE in the 20% force condition (R = 0.306, p = 0.021) and length of hold and overshoot above target force explained explicit PE in the 40% (R = 0.399, p = 0.014 and 0.004) force condition. In the 60% force condition, greater explicit PE was explained by higher force variability (R = 0.315, p = 0.017). None of the correlations were significant for state fatigue. Conclusion Trait fatigue, but not state fatigue, correlating with measures of PE and motor performance, may suggest that altered perception may lead to high fatigue mediated by changes in motor performance. This finding furthers our mechanistic understanding of poststroke fatigue.
Collapse
Affiliation(s)
- William De Doncker
- From the Department of Clinical and Movement Neuroscience, (W.D.D., S.O., A.K.) Institute of Neurology, and Institute of Cognitive Neuroscience (L.C., S.O.), UCL, London, UK
| | - Lucie Charles
- From the Department of Clinical and Movement Neuroscience, (W.D.D., S.O., A.K.) Institute of Neurology, and Institute of Cognitive Neuroscience (L.C., S.O.), UCL, London, UK
| | - Sasha Ondobaka
- From the Department of Clinical and Movement Neuroscience, (W.D.D., S.O., A.K.) Institute of Neurology, and Institute of Cognitive Neuroscience (L.C., S.O.), UCL, London, UK
| | - Annapoorna Kuppuswamy
- From the Department of Clinical and Movement Neuroscience, (W.D.D., S.O., A.K.) Institute of Neurology, and Institute of Cognitive Neuroscience (L.C., S.O.), UCL, London, UK.
| |
Collapse
|
17
|
De Doncker W, Kuppuswamy A. P14 Neurophysiology of post-stroke fatigue. Clin Neurophysiol 2020. [DOI: 10.1016/j.clinph.2019.12.125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
18
|
|
19
|
De Doncker W, Dantzer R, Ormstad H, Kuppuswamy A. Mechanisms of poststroke fatigue. J Neurol Neurosurg Psychiatry 2018; 89:287-293. [PMID: 28939684 DOI: 10.1136/jnnp-2017-316007] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 09/05/2017] [Accepted: 09/07/2017] [Indexed: 11/04/2022]
Abstract
Poststroke fatigue is a debilitating symptom and is poorly understood. Here we summarise molecular, behavioural and neurophysiological changes related to poststroke fatigue and put forward potential theories for mechanistic understanding of poststroke fatigue.
Collapse
Affiliation(s)
| | - Robert Dantzer
- Department of Symptom Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Heidi Ormstad
- Faculty of Health and Social Sciences, University of South West Norway, Oslo, Norway
| | | |
Collapse
|
20
|
Clark EV, Ward NS, Kuppuswamy A. Prior physical exertion modulates allocentric distance perception: a demonstration of task-irrelevant cross-modal transfer. Exp Brain Res 2016; 234:2363-7. [PMID: 27052884 PMCID: PMC4923087 DOI: 10.1007/s00221-016-4641-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 03/25/2016] [Indexed: 11/23/2022]
Abstract
Physical exertion has been previously shown to influence distance perception in the egocentric framework. In this study, we show that physical exertion influences allocentric distance perception. Twenty healthy volunteers made allocentric line length estimates following varying levels of physical exertion. Each participant was presented with 30 different line lengths ranging from 1 to 12 cm, and each length was presented three times. Each line presentation was preceded by the participant exerting one of the following three levels of their maximal voluntary force (MVF): 20, 50, or 80 % MVF using their hand in the pinch force task. Psychometric curves were obtained for the lines perceived as ‘long’ following each of the three force levels. Lines that were perceived as ‘short’ following 20 and 50 % MVF were perceived as ‘long’ following 80 % MVF; that is, there was a significant leftward shift in the psychometric curve following 80 % MVF when compared to 20 and 50 % MVF. Here, we demonstrate that physical exertion influences perception of distances in the allocentric framework. We discuss our findings with respect to cross-modal interactions, fatigue physiology, peri- and extra-personal space interactions.
Collapse
Affiliation(s)
- Ella V Clark
- Institute of Neurology, University College London, 33, Queen Square, London, WC1N 3BG, UK
| | - Nick S Ward
- Institute of Neurology, University College London, 33, Queen Square, London, WC1N 3BG, UK
| | - Annapoorna Kuppuswamy
- Institute of Neurology, University College London, 33, Queen Square, London, WC1N 3BG, UK.
| |
Collapse
|
21
|
Wu S, Duncan F, Anderson NH, Kuppuswamy A, Macloed MR, Mead GE. Exploratory Cohort Study of Associations between Serum C - Reactive Protein and Fatigue after Stroke. PLoS One 2015; 10:e0143784. [PMID: 26599129 PMCID: PMC4658028 DOI: 10.1371/journal.pone.0143784] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 11/09/2015] [Indexed: 02/05/2023] Open
Abstract
Background and Aim Post-stroke fatigue is a common and distressing problem but little is known about its biological mechanisms. This cohort study was to investigate associations between C-reactive protein (CRP) and fatigue after stroke. Methods Patients were assessed at one, six and 12 months after their stroke onset, with the Fatigue Assessment Scale, a case definition of post-stroke fatigue, Hospital Anxiety and Depression Scale, and daily step counts. Blood samples were collected at each assessment and the CRP level was determined by a standard CRP immunoassay. Cross-sectional associations between CRP and fatigue at each time point were determined by Pearson correlation coefficient and independent-samples t-test. Whether CRP levels at one month predict fatigue scores at six and 12 months was explored by multiple linear regression, with anxiety, depression, and daily step counts as covariates. Results Sixty-five patients (mean age 67 years, 65% men) were included: 61 at one month, 49 at six months, and 41 at 12 months. CRP levels and fatigue scores were not associated at one month (p = 0.88) or 12 months (p = 0.56), but weakly associated at six months (r = 0.27, p = 0.04); however, this association was no longer significant (p = 0.14) after controlling for the effects of covariates. The CRP level was not associated with the fulfilment of case definition of post-stroke fatigue at any time points (all p > 0.05). The CRP level at one month was not a significant predictor for fatigue levels at either six months (p = 0.93) or 12 months (p = 0.78). Conclusions There is insufficient evidence for the association between CRP and PSF in stroke patients. Future studies with larger sample sizes and controlling for potential confounders are needed to investigate whether this association exists.
Collapse
Affiliation(s)
- Simiao Wu
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, China
| | - Fiona Duncan
- School of Health and Life Sciences, Glasgow Caledonian University, Glasgow, United Kingdom
| | - Niall H. Anderson
- Centre for Population Health Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Annapoorna Kuppuswamy
- Sobell Department of Motor Neuroscience, University of College London, London, United Kingdom
| | - Malcolm R. Macloed
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Gillian E. Mead
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- * E-mail:
| |
Collapse
|
22
|
Kuppuswamy A, Clark EV, Sandhu KS, Rothwell JC, Ward NS. Post-stroke fatigue: a problem of altered corticomotor control? J Neurol Neurosurg Psychiatry 2015; 86:902-4. [PMID: 25886778 DOI: 10.1136/jnnp-2015-310431] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 03/23/2015] [Indexed: 11/03/2022]
Abstract
OBJECTIVES We recently showed that diminished motor cortical excitability is associated with high levels of post-stroke fatigue. Motor cortex excitability impacts movement parameters such as reaction and movement times. We predicted that one or both would be influenced by the presence of post-stroke fatigue. METHODS 41 first-time stroke survivors (high fatigue n=21, Fatigue Severity Scale 7 (FSS-7) score >5; low fatigue n=20, FSS-7 score <3) participated in the study. Movement times, choice and simple reaction times were measured in all participants. RESULTS A three way ANOVA with fatigue (high and low), task (movement time, simple reaction time and choice reaction time) and hand (affected and unaffected) as the three factors, revealed a significant difference between affected (but not unaffected) hand movement times in the high compared to low fatigue groups. Reaction times, however, were not different between the high-fatigue and low-fatigue groups in either the affected or unaffected hand. CONCLUSIONS Previously, we showed that motor cortex excitability is lower in patients with high post-stroke fatigue. Our current findings suggest that post-stroke fatigue (1) is a problem of movement speed (possibly a consequence of diminished motor cortex excitability) and not movement preparation, and (2) may have a focal origin confined to the lesioned hemisphere. We suggest that low motor cortex excitability in the lesioned hemisphere is a viable therapeutic target in post-stroke fatigue.
Collapse
Affiliation(s)
- A Kuppuswamy
- Sobell Department of Motor Neuroscience, Institute of Neurology, UCL, London, UK
| | - E V Clark
- Sobell Department of Motor Neuroscience, Institute of Neurology, UCL, London, UK
| | - K S Sandhu
- Sobell Department of Motor Neuroscience, Institute of Neurology, UCL, London, UK
| | - J C Rothwell
- Sobell Department of Motor Neuroscience, Institute of Neurology, UCL, London, UK
| | - N S Ward
- Sobell Department of Motor Neuroscience, Institute of Neurology, UCL, London, UK
| |
Collapse
|
23
|
Abstract
Poststroke fatigue and limb heaviness are 2 perceptual problems that commonly occur after stroke. Previous work suggests that poststroke fatigue may be related to altered sensorimotor processing whereas limb heaviness is often considered an association of muscle weakness. To address the hypothesis that the perception of limb heaviness may also be a problem of altered sensorimotor control, we investigated whether it was more closely related to poststroke fatigue or muscle weakness. In 69 chronic stroke survivors, we found that those with high perceived limb heaviness (31 individuals) also reported significantly higher levels of fatigue (4.8/7) than those with no perceived limb heaviness (38 individuals, fatigue score = 2.68/7), but there was no difference in weakness between the 2 groups. This intriguing finding is discussed in relation to effort perception and sensory processing. The association between limb heaviness and poststroke fatigue and a dissociation from muscle weakness gives rise to the hypothesis that limb heaviness maybe a centrally arising sensorimotor disorder.
Collapse
|
24
|
Abstract
The pathophysiology of post-stroke fatigue is poorly understood although it is thought to be a consequence of central nervous system pathophysiology. In this study we investigate the relationship between corticomotor excitability and self-reported non-exercise related fatigue in chronic stroke population. Seventy first-time non-depressed stroke survivors (60.36 ± 12.4 years, 20 females, 56.81 ± 63 months post-stroke) with minimal motor and cognitive impairment were included in the cross-sectional observational study. Fatigue was measured using two validated questionnaires: Fatigue Severity Scale 7 and Neurological Fatigue Index - Stroke. Perception of effort was measured using a 0-10 numerical rating scale in an isometric biceps hold-task and was used as a secondary measure of fatigue. Neurophysiological measures of corticomotor excitability were performed using transcranial magnetic stimulation. Corticospinal excitability was quantified using resting and active motor thresholds and stimulus-response curves of the first dorsal interosseous muscle. Intracortical M1 excitability was measured using paired pulse paradigms: short and long interval intracortical inhibition in the same hand muscle as above. Excitability of cortical and subcortical inputs that drive M1 output was measured in the biceps muscle using a modified twitch interpolation technique to provide an index of central activation failure. Stepwise regression was performed to determine the explanatory variables that significantly accounted for variance in the fatigue and perception scores. Resting motor threshold (R = 0.384; 95% confidence interval = 0.071; P = 0.036) accounted for 14.7% (R(2)) of the variation in Fatigue Severity Scale 7. Central activation failure (R = 0.416; 95% confidence interval = -1.618; P = 0.003) accounted for 17.3% (R(2)) of the variation in perceived effort score. Thus chronic stroke survivors with high fatigue exhibit high motor thresholds and those who perceive high effort have low excitability of inputs that drive motor cortex output. We suggest that low excitability of both corticospinal output and its facilitatory synaptic inputs from cortical and sub-cortical sites contribute to high levels of fatigue after stroke.
Collapse
Affiliation(s)
| | - Ella V Clark
- Sobell Department of Motor Neuroscience, Institute of Neurology, UCL, London, UK
| | - Isobel F Turner
- Sobell Department of Motor Neuroscience, Institute of Neurology, UCL, London, UK
| | - John C Rothwell
- Sobell Department of Motor Neuroscience, Institute of Neurology, UCL, London, UK
| | - Nick S Ward
- Sobell Department of Motor Neuroscience, Institute of Neurology, UCL, London, UK
| |
Collapse
|
25
|
Kuppuswamy A, Clark E, Turner I, Rothwell J, Ward N. P349: Fatigue after stroke is related to motor cortex “restfulness” and not to physical or cognitive functional ability. Clin Neurophysiol 2014. [DOI: 10.1016/s1388-2457(14)50463-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
26
|
Elumogo T, Booth D, Enoch D, Kuppuswamy A, Tremlett C, Williams C, Shankar A, Morter S. Bordetella pertussis in a neonatal intensive care unit: identification of the mother as the likely source. J Hosp Infect 2012; 82:133-5. [DOI: 10.1016/j.jhin.2012.07.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Accepted: 07/12/2012] [Indexed: 10/27/2022]
|
27
|
Jola C, Abedian-Amiri A, Kuppuswamy A, Pollick FE, Grosbras MH. Motor simulation without motor expertise: enhanced corticospinal excitability in visually experienced dance spectators. PLoS One 2012; 7:e33343. [PMID: 22457754 PMCID: PMC3310063 DOI: 10.1371/journal.pone.0033343] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Accepted: 02/14/2012] [Indexed: 11/18/2022] Open
Abstract
The human “mirror-system” is suggested to play a crucial role in action observation and execution, and is characterized by activity in the premotor and parietal cortices during the passive observation of movements. The previous motor experience of the observer has been shown to enhance the activity in this network. Yet visual experience could also have a determinant influence when watching more complex actions, as in dance performances. Here we tested the impact visual experience has on motor simulation when watching dance, by measuring changes in corticospinal excitability. We also tested the effects of empathic abilities. To fully match the participants' long-term visual experience with the present experimental setting, we used three live solo dance performances: ballet, Indian dance, and non-dance. Participants were either frequent dance spectators of ballet or Indian dance, or “novices” who never watched dance. None of the spectators had been physically trained in these dance styles. Transcranial magnetic stimulation was used to measure corticospinal excitability by means of motor-evoked potentials (MEPs) in both the hand and the arm, because the hand is specifically used in Indian dance and the arm is frequently engaged in ballet dance movements. We observed that frequent ballet spectators showed larger MEP amplitudes in the arm muscles when watching ballet compared to when they watched other performances. We also found that the higher Indian dance spectators scored on the fantasy subscale of the Interpersonal Reactivity Index, the larger their MEPs were in the arms when watching Indian dance. Our results show that even without physical training, corticospinal excitability can be enhanced as a function of either visual experience or the tendency to imaginatively transpose oneself into fictional characters. We suggest that spectators covertly simulate the movements for which they have acquired visual experience, and that empathic abilities heighten motor resonance during dance observation.
Collapse
Affiliation(s)
- Corinne Jola
- School of Psychology, University of Surrey, Guildford, United Kingdom.
| | | | | | | | | |
Collapse
|
28
|
Evans N, Harris N, Kuppuswamy A. A smarter future: technology to enhance an independent lifestyle for our future selves. International Journal of Therapy and Rehabilitation 2011. [DOI: 10.12968/ijtr.2011.18.12.694] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Nina Evans
- Bath Institute of Medical Engineering (BIME), The Wolfson Centre, Royal United Hospital, Bath, UK
| | - Nigel Harris
- Bath Institute of Medical Engineering (BIME), The Wolfson Centre, Royal United Hospital, Bath, UK
| | | |
Collapse
|
29
|
Kuppuswamy A, Balasubramaniam AV, Maksimovic R, Mathias CJ, Gall A, Craggs MD, Ellaway PH. Action of 5 Hz repetitive transcranial magnetic stimulation on sensory, motor and autonomic function in human spinal cord injury. Clin Neurophysiol 2011; 122:2452-61. [PMID: 21600843 DOI: 10.1016/j.clinph.2011.04.022] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Revised: 04/21/2011] [Accepted: 04/26/2011] [Indexed: 10/18/2022]
Abstract
OBJECTIVE To assess the effectiveness of physiological outcome measures in detecting functional change in the degree of impairment of spinal cord injury (SCI) following repetitive transcranial magnetic stimulation (rTMS) of the sensorimotor cortex. METHODS Subjects with complete or incomplete cervical (or T1) SCI received real and sham rTMS in a randomised placebo-controlled single-blinded cross-over trial. rTMS at sub-threshold intensity for upper-limb muscles was applied (5 Hz, 900 stimuli) on 5 consecutive days. Assessments made before and for 2 weeks after treatment comprised the ASIA (American Spinal Injuries Association) impairment scale (AIS), the Action Research Arm Test (ARAT), a peg-board test, electrical perceptual test (EPT), motor evoked potentials, cortical silent period, cardiovascular and sympathetic skin responses. RESULTS There were no significant differences in AIS outcomes between real and sham rTMS. The ARAT was increased at 1h after real rTMS compared to baseline. Active motor threshold for the most caudally innervated hand muscle was increased at 72 and 120 h compared to baseline. Persistent reductions in EPT to rTMS occurred in two individuals. CONCLUSIONS Changes in cortical motor threshold measures may accompany functional gains to rTMS in SCI subjects. SIGNIFICANCE Electrophysiological measures may provide a useful adjunct to ASIA impairment scales.
Collapse
Affiliation(s)
- A Kuppuswamy
- Division of Experimental Medicine, Imperial College London, London W6 8RP, UK
| | | | | | | | | | | | | |
Collapse
|
30
|
Ellaway P, Kuppuswamy A, Balasubramaniam A, Maksimovic R, Gall A, Craggs M, Mathias C, Bacon M, Prochazka A, Kowalczewski J, Conway B, Galen S, Catton C, Allan D, Curt A, Wirth B, van Hedel H. Development of quantitative and sensitive assessments of physiological and functional outcome during recovery from spinal cord injury: A Clinical Initiative. Brain Res Bull 2011; 84:343-57. [DOI: 10.1016/j.brainresbull.2010.08.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2010] [Revised: 08/11/2010] [Accepted: 08/12/2010] [Indexed: 01/30/2023]
|
31
|
Ellaway P, Kuppuswamy A, Nicotra A, Mathias C. Sweat production and the sympathetic skin response: Improving the clinical assessment of autonomic function. Auton Neurosci 2010; 155:109-14. [DOI: 10.1016/j.autneu.2010.01.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2009] [Revised: 01/04/2010] [Accepted: 01/11/2010] [Indexed: 10/19/2022]
|
32
|
Ramanathan G, Jayakar GG, Kuppuswamy A, Ramamurthy B, Patil S. Case study: Managing a case of ankylosing spondylitis for inguinal hernia repair. Southern African Journal of Anaesthesia and Analgesia 2010. [DOI: 10.1080/22201173.2010.10872667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
33
|
Ellaway PH, Catley M, Davey NJ, Kuppuswamy A, Strutton P, Frankel HL, Jamous A, Savic G. Review of physiological motor outcome measures in spinal cord injury using transcranial magnetic stimulation and spinal reflexes. ACTA ACUST UNITED AC 2009; 44:69-76. [PMID: 17551860 DOI: 10.1682/jrrd.2005.08.0140] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
This article reviews methods that have been developed as part of a clinical initiative on improving outcome measures for motor function assessment in subjects with spinal cord injury (SCI). Physiological motor outcome measures originally developed for limbs-transcranial magnetic stimulation (TMS) of the motor cortex to elicit motor-evoked potentials (MEPs) and mechanical stimulation to elicit spinal reflexes-have been extended to muscles of the trunk. The impetus for this development is the lack of a motor component in the American Spinal Injury Association clinical assessment for the thoracic myotomes. The application of TMS to the assessment of limb muscles is reviewed, followed by consideration of its application to the assessment of paravertebral and intercostal muscles. Spinal reflex testing of paravertebral muscles is also described. The principal markers for the thoracic SCI motor level that have emerged from this clinical initiative are (1) the threshold of MEPs in paravertebral muscles in response to TMS of the motor cortex, (2) the facilitation pattern and latency of MEPs in intercostal muscles during voluntary expiratory effort, and (3) the absence of long-latency reflex responses and the exaggeration of short-latency reflex responses in paravertebral muscles.
Collapse
Affiliation(s)
- Peter H Ellaway
- Division of Neuroscience and Mental Health, Imperial College London, Charing Cross Campus, St Dunstan's Rd, London W6 8RP, UK.
| | | | | | | | | | | | | | | |
Collapse
|
34
|
Triscott S, Gordon J, Kuppuswamy A, King N, Davey N, Ellaway P. Differential effects of endurance and resistance training on central fatigue. J Sports Sci 2008; 26:941-51. [DOI: 10.1080/02640410701885439] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
35
|
Kuppuswamy A, Ellaway P. Effects of unilateral 10Hz repetitive transcranial magnetic stimulation (rTMS) on the excitability of corticospinal and inter-hemispheric pathways in humans. Brain Stimul 2008. [DOI: 10.1016/j.brs.2008.06.058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
|
36
|
Kuppuswamy A, Nicotra A, King NKK, Ellaway P. MO21 Contribution of the cortex to sympathetic skin response studied using image-guided repetitive transcranial magnetic stimulation (rTMS) in healthy individuals. Clin Neurophysiol 2008. [DOI: 10.1016/s1388-2457(08)60046-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
37
|
Kuppuswamy A, Catley M, King NKK, Strutton PH, Davey NJ, Ellaway PH. Cortical control of erector spinae muscles during arm abduction in humans. Gait Posture 2008; 27:478-84. [PMID: 17644335 DOI: 10.1016/j.gaitpost.2007.06.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2007] [Revised: 04/25/2007] [Accepted: 06/09/2007] [Indexed: 02/02/2023]
Abstract
Abduction of one arm preferentially activates erector spinae muscles on the other side to stabilise the body. We hypothesise that the corticospinal drive to the arm abductors and the erector spinae may originate from the same hemisphere. In 18 subjects, transcranial magnetic stimulation (TMS) was applied using an angle double-cone coil placed symmetrically over the vertex. Motor evoked potentials (MEP) could not be evoked systematically seated at rest but could be evoked bilaterally in erector spinae muscles during unilateral arm abduction. TMS was applied at 110% and 120% motor threshold (MT) for the contralateral erector spinae muscle when an arm was abducted against resistance. The electromyographic (EMG) activity in the erector spinae at L4 vertebral level during contralateral arm abduction was significantly higher (P<0.05) than in the ipsilateral erector spinae. The mean (+/-S.E.M.) latencies of MEPs in the contralateral muscle to TMS at 120%MT (left 16.0+/-0.8 ms; right 17.0+/-0.8 ms) were significantly (P<0.05) longer than in the ipsilateral erector spinae (13.9+/-1.0 ms; 16.6+/-0.4 ms). In two of six subjects from the same group, it was possible to elicit MEPs by TMS applied selectively to one hemisphere using a figure-of-eight coil. MEPs ipsilateral to the TMS had longer latencies than contralateral MEPs. The study revealed an unexpectedly longer rather than shorter latency of the MEP recorded from the lumbar erector spinae muscles when co-activated during abduction of the opposite arm. A speculative explanation is that TMS might activate back muscles contralateral to arm abduction via an uncrossed, ipsilateral corticospinal tract that is slower conducting than the conventional crossed corticospinal tract. The study has implications for the design of measures to promote recovery and rehabilitation of motor function in disorders such as stroke and spinal cord injury.
Collapse
Affiliation(s)
- Annapoorna Kuppuswamy
- Division of Neuroscience and Mental Health, Imperial College London, Charing Cross Campus, London W6 8RP, UK
| | | | | | | | | | | |
Collapse
|
38
|
Kuppuswamy A, Theodorou S, Catley M, Strutton PH, Ellaway PH, McGregor AH, Davey NJ. Motor neurone excitability in back muscles assessed using mechanically evoked reflexes in spinal cord injured patients. J Neurol Neurosurg Psychiatry 2005; 76:1259-63. [PMID: 16107363 PMCID: PMC1739798 DOI: 10.1136/jnnp.2004.045021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE The clinical and functional assessment of back muscles in human spinal cord injury (SCI) has received little attention. The aim of this study was to develop a method to assess the level of a thoracic spinal cord lesion based on the reflex activation of back muscles. METHODS In 11 control subjects and in 12 subjects with clinically complete thoracic SCI (T2-T12), either a spinous process or an erector spinae muscle was prodded to elicit short latency reflexes recorded electromyographically at the spinal level of stimulation. An electromagnetic servo, attached to a blunt probe, applied stimuli at a frequency of 1 Hz and amplitude of 3 mm. Two trials of 50 mechanical prods were conducted at each site. RESULTS Reflexes were evoked in control subjects in 82% of trials when the spinous process was prodded, and in 80% of trials when the muscle was prodded. In contrast, reflexes in SCI subjects could be elicited in 90-100% of trials two segments either above or below the lesion. Reflex responses in control subjects had a mean (SEM) latency of 5.72 (0.53) ms when the spinous process was prodded, and 5.42 (0.42) ms when the muscle was prodded. In the SCI subjects, responses had slightly (but insignificantly) longer latencies both above and below the lesion to either stimulus. The amplitude of reflex responses, expressed as a percentage of the background EMG, was on average 2-3 times larger at the three vertebral levels spanning the lesion in SCI subjects than at sites above or below the lesion or at any level in control subjects. CONCLUSION We propose that the size of these mechanically evoked reflexes may be useful in determining the level of thoracic SCI. Furthermore, the reflexes might provide a valuable tool with which to monitor recovery after an intervention to repair or improve function of a damaged spinal cord.
Collapse
Affiliation(s)
- A Kuppuswamy
- Department of Movement and Balance, Division of Neuroscience and Psychological Medicine, Imperial College Faculty of Medicine, Charing Cross Campus, St Dunstan's Road, London W6 8RP, UK.
| | | | | | | | | | | | | |
Collapse
|
39
|
King NKK, Kuppuswamy A, Strutton PH, Davey NJ. Estimation of cortical silent period following transcranial magnetic stimulation using a computerised cumulative sum method. J Neurosci Methods 2005; 150:96-104. [PMID: 16105686 DOI: 10.1016/j.jneumeth.2005.06.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2005] [Revised: 06/06/2005] [Accepted: 06/07/2005] [Indexed: 11/24/2022]
Abstract
The cortical silent period (CSP) following transcranial magnetic stimulation (TMS) of the motor cortex can be used to measure intra-cortical inhibition and changes in a number of important pathologies affecting the central nervous system. The main drawback of this technique has been the difficulty in accurately identifying the onset and offset of the cortical silent period leading to inter-observer variability. We developed an automated method based on the cumulative sum (Cusum) technique to improve the determination of the duration and area of the cortical silent period. This was compared with experienced raters and two other automated methods. We showed that the automated Cusum method reliably correlated with the experienced raters for both duration and area of CSP. Compared with the automated methods, the Cusum also showed the strongest correlation with the experienced raters. Our results show the Cusum method to be a simple, graphical and powerful method of detecting low-intensity CSP that can be easily automated using standard software.
Collapse
Affiliation(s)
- Nicolas K K King
- Department of Movement and Balance, Division of Neuroscience, Imperial College, Charing Cross Campus, London W6 8RP, UK.
| | | | | | | |
Collapse
|
40
|
Specterman M, Bhuiya A, Kuppuswamy A, Strutton PH, Catley M, Davey NJ. The effect of an energy drink containing glucose and caffeine on human corticospinal excitability. Physiol Behav 2005; 83:723-8. [PMID: 15639157 DOI: 10.1016/j.physbeh.2004.09.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2004] [Revised: 07/02/2004] [Accepted: 09/16/2004] [Indexed: 11/29/2022]
Abstract
Glucose- and caffeine-containing energy drinks are said to influence the cognitive and cellular function within the brain. In this study, we have used the size of motor-evoked potentials (MEPs) produced in response to transcranial magnetic stimulation (TMS) of the motor cortex as an index of corticospinal excitability after ingestion of Lucozade and control drinks of glucose-containing or caffeine-containing carbonated water or carbonated water alone. With local ethical approval and informed consent, 10 healthy volunteers took part; surface electromyographic (EMG) recordings were taken from the thenar muscles of the dominant hand. In each assessment, 15 TMS stimuli were delivered over the motor cortex at an intensity of 1.1 T. Six subjects ingested a 380-ml bottle of carbonated Lucozade drink containing 68 g of glucose and 46 mg caffeine. Four subjects took part in three control trials drinking: (A) carbonated water with caffeine, (B) carbonated water with glucose and (C) carbonated water alone. Assessments were made before and at 30-min intervals after each drink. Mean fasting blood glucose concentrations and mean areas of MEPs rose after the Lucozade, remaining elevated for 90 min. Similar rises in MEP areas were seen in trials after drinking carbonated water with caffeine or with glucose, but not after drinking carbonated water alone. No change was seen in the M-wave evoked by electrical stimulation of the ulnar nerve. We conclude that Lucozade can affect the size of MEPs to activation of the motor cortex with fixed-intensity TMS. The underlying mechanism is likely to relate to the combined effects of caffeine and glucose on the brain.
Collapse
Affiliation(s)
- M Specterman
- Division of Neuroscience and Psychological Medicine, Department of Movement and Balance, Imperial College London, Charing Cross Hospital, London W6 8RF, UK
| | | | | | | | | | | |
Collapse
|