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Kim H, Kim J, Kim J, Oh S, Choi K, Yoon J. Magnetothermal-based non-invasive focused magnetic stimulation for functional recovery in chronic stroke treatment. Sci Rep 2023; 13:4988. [PMID: 36973390 PMCID: PMC10042827 DOI: 10.1038/s41598-023-31979-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 03/21/2023] [Indexed: 03/29/2023] Open
Abstract
Magnetic heat-based brain stimulation of specific lesions could promote the restoration of impaired motor function caused by chronic stroke. We delivered localized stimulation by nanoparticle-mediated heat generation within the targeted brain area via focused magnetic stimulation. The middle cerebral artery occlusion model was prepared, and functional recovery in the chronic-phase stroke rat model was demonstrated by the therapeutic application of focused magnetic stimulation. We observed a transient increase in blood-brain barrier permeability at the target site of < 4 mm and metabolic brain activation at the target lesion. After focused magnetic stimulation, the rotarod score increased by 390 ± 28% (p < 0.05) compared to the control group. Standardized uptake value in the focused magnetic stimulation group increased by 2063 ± 748% (p < 0.01) compared to the control group. Moreover, an increase by 24 ± 5% (p < 0.05) was observed in the sham group as well. Our results show that non-invasive focused magnetic stimulation can safely modulate BBB permeability and enhance neural activation for chronic-phase stroke treatment in the targeted deep brain area.
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Affiliation(s)
- Hohyeon Kim
- School of Integrated Technology, Gwangju Institute of Science and Technology, Gwangju, 61005, South Korea
| | - Jihye Kim
- Department of Neurology, Chonnam National University Hospital and Medical School, 8 Hak-dong, Dong-gu, Gwangju, 501-757, South Korea
| | - Jahae Kim
- Department of Nuclear Medicines, Chonnam National University Hospital and Medical School, 8 Hak-dong, Dong-gu, Gwangju, 501-757, South Korea
| | - Seungjun Oh
- School of Integrated Technology, Gwangju Institute of Science and Technology, Gwangju, 61005, South Korea
| | - Kangho Choi
- Department of Neurology, Chonnam National University Hospital and Medical School, 8 Hak-dong, Dong-gu, Gwangju, 501-757, South Korea.
| | - Jungwon Yoon
- School of Integrated Technology, Gwangju Institute of Science and Technology, Gwangju, 61005, South Korea.
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2
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Chou TY, Wang JC, Lin MY, Tsai PY. Low-Frequency vs. Theta Burst Transcranial Magnetic Stimulation for the Treatment of Chronic Non-fluent Aphasia in Stroke: A Proof-of-Concept Study. Front Aging Neurosci 2022; 13:800377. [PMID: 35095477 PMCID: PMC8795082 DOI: 10.3389/fnagi.2021.800377] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Accepted: 12/27/2021] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Although low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) has shown promise in the treatment of poststroke aphasia, the efficacy of high-frequency rTMS (HF-rTMS) has yet to be determined. PURPOSE We investigated the efficacy of intermittent theta burst stimulation (iTBS) in ameliorating chronic non-fluent aphasia and compared it with that of LF-rTMS. METHODS We randomly assigned patients with poststroke non-fluent aphasia to an ipsilesional iTBS (n = 29), contralesional 1-Hz rTMS (n = 27), or sham (n = 29) group. Each group received the rTMS protocol executed in 10 daily sessions over 2 weeks. We evaluated language function before and after the intervention by using the Concise Chinese Aphasia Test (CCAT). RESULTS Compared with the sham group, the iTBS group exhibited significant improvements in conversation, description, and expression scores (P = 0.0004-0.031), which characterize verbal production, as well as in auditory comprehension, reading comprehension, and matching scores (P < 0.01), which characterize language perception. The 1-Hz group exhibited superior improvements in expression, reading comprehension, and imitation writing scores compared with the sham group (P < 0.05). The iTBS group had significantly superior results in CCAT total score, matching and auditory comprehension (P < 0.05) relative to the 1-Hz group. CONCLUSION Our study findings contribute to a growing body of evidence that ipsilesional iTBS enhances the language recovery of patients with non-fluent aphasia after a chronic stroke. Auditory comprehension was more preferentially enhanced by iTBS compared with the 1-Hz protocol. Our findings highlight the importance of ipsilesional modulation through excitatory rTMS for the recovery of non-fluent aphasia in patients with chronic stroke. CLINICAL TRIAL REGISTRATION [www.ClinicalTrials.gov], identifier [NCT03059225].
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Affiliation(s)
- Ting-Yu Chou
- Department of Physical Medicine and Rehabilitation, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Jia-Chi Wang
- Department of Physical Medicine and Rehabilitation, Taipei Veterans General Hospital, Taipei, Taiwan
- School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Mu-Yun Lin
- Department of Physical Medicine and Rehabilitation, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Po-Yi Tsai
- Department of Physical Medicine and Rehabilitation, Taipei Veterans General Hospital, Taipei, Taiwan
- School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
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3
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Ho A, Khan Y, Fischberg G, Mahato D. Clinical Application of Brain Plasticity in Neurosurgery. World Neurosurg 2020; 146:31-39. [PMID: 32916359 DOI: 10.1016/j.wneu.2020.09.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/03/2020] [Accepted: 09/04/2020] [Indexed: 01/15/2023]
Abstract
Brain plasticity is an ongoing process of reorganization not only on the macroscopic level but also from underlying changes at the cellular and molecular levels of neurons. This evolution has not yet been fully understood. The objective of this paper is to review and understand neuroplasticity through the review of literature, imaging, and intraoperative evidence.
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Affiliation(s)
- Alison Ho
- Department of Neurosurgery, Desert Regional Medical Center, Palm Springs, California, USA
| | - Yasir Khan
- Department of Neurosurgery, Desert Regional Medical Center, Palm Springs, California, USA
| | - Glenn Fischberg
- Department of Neurosurgery, Desert Regional Medical Center, Palm Springs, California, USA
| | - Deependra Mahato
- Department of Neurosurgery, Desert Regional Medical Center, Palm Springs, California, USA.
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4
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Versace V, Schwenker K, Langthaler PB, Golaszewski S, Sebastianelli L, Brigo F, Pucks-Faes E, Saltuari L, Nardone R. Facilitation of Auditory Comprehension After Theta Burst Stimulation of Wernicke's Area in Stroke Patients: A Pilot Study. Front Neurol 2020; 10:1319. [PMID: 31969857 PMCID: PMC6960103 DOI: 10.3389/fneur.2019.01319] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 11/28/2019] [Indexed: 12/27/2022] Open
Abstract
Introduction: Single-pulse transcranial magnetic stimulation (TMS) and high-frequency repetitive TMS (rTMS) over Wernicke's area were found to facilitate language functions in right-handed healthy subjects. We aimed at investigating the effects of excitatory rTMS, given as intermittent theta burst stimulation (iTBS) over left Wernicke's area, on auditory comprehension in patients suffering from fluent aphasia after stroke of the left temporal lobe. Methods: We studied 13 patients with chronic fluent aphasia after an ischemic stroke involving Wernicke's area. iTBS was applied in random order to Wernicke's area, the right-hemisphere homologous of Wernicke's area, and the primary visual cortex. Auditory comprehension was blind assessed using the Token test before (T0), 5 (T1), and 40 min (T2) after a single session of iTBS. Results: At the first evaluation (T1) after iTBS on left Wernike's area, but not on the contralateral homologous area nor on the primary visual cortex, the scores on the Token test were significantly increased. No significant effects were observed at T2. Conclusion: We demonstrated that a single session of excitatory iTBS over Wernicke's area was safe and led to a transient facilitation of auditory comprehension in chronic stroke patients with lesions in the same area. Further studies are needed to establish whether TBS-induced modulation can be enhanced and transformed into longer-lasting effects by means of repeated TBS sessions and by combining TBS with speech and language therapy.
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Affiliation(s)
- Viviana Versace
- Department of Neurorehabilitation, Hopsital of Vipiteno-Sterzing, Vipiteno-Sterzing, Italy.,Research Unit for Neurorehabilitation of South Tyrol, Bolzano, Italy
| | - Kerstin Schwenker
- Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University, Salzburg, Austria.,Karl Landsteiner Institut für Neurorehabilitation und Raumfahrtneurologie, Salzburg, Austria
| | - Patrick B Langthaler
- Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University, Salzburg, Austria
| | - Stefan Golaszewski
- Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University, Salzburg, Austria.,Karl Landsteiner Institut für Neurorehabilitation und Raumfahrtneurologie, Salzburg, Austria
| | - Luca Sebastianelli
- Department of Neurorehabilitation, Hopsital of Vipiteno-Sterzing, Vipiteno-Sterzing, Italy.,Research Unit for Neurorehabilitation of South Tyrol, Bolzano, Italy
| | - Francesco Brigo
- Department of Neurology, Franz Tappeiner Hospital, Merano, Italy.,Department of Neuroscience, Biomedicine and Movement Science, University of Verona, Verona, Italy
| | | | - Leopold Saltuari
- Research Unit for Neurorehabilitation of South Tyrol, Bolzano, Italy.,Department of Neurology, Hochzirl Hospital, Zirl, Austria
| | - Raffaele Nardone
- Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University, Salzburg, Austria.,Karl Landsteiner Institut für Neurorehabilitation und Raumfahrtneurologie, Salzburg, Austria.,Department of Neurology, Franz Tappeiner Hospital, Merano, Italy
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5
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Zhuang M, Wu Q, Wan F, Hu Y. State-of-the-art non-invasive brain–computer interface for neural rehabilitation: A review. JOURNAL OF NEURORESTORATOLOGY 2020. [DOI: 10.26599/jnr.2020.9040001] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Brain–computer interface (BCI) is a novel communication method between brain and machine. It enables signals from the human brain to influence or control external devices. Currently, much research interest is focused on the BCI-based neural rehabilitation of patients with motor and cognitive diseases. Over the decades, BCI has become an alternative treatment for motor and cognitive rehabilitation. Previous studies demonstrated the usefulness of BCI intervention in restoring motor function and recovery of the damaged brain. Electroencephalogram (EEG)-based BCI intervention could cast light on the mechanisms underlying neuroplasticity during upper limb recovery by providing feedback to the damaged brain. BCI could act as a useful tool to aid patients with daily communication and basic movement in severe motor loss cases like amyotrophic lateral sclerosis (ALS). Furthermore, recent findings have reported the therapeutic efficacy of BCI in people suffering from other diseases with different levels of motor impairment such as spastic cerebral palsy, neuropathic pain, etc. Besides motor functional recovery, BCI also plays its role in improving the behavior of patients with cognitive diseases like attention-deficit/hyperactivity disorder (ADHD). The BCI-based neurofeedback training is focused on either reducing the ratio of theta and beta rhythm, or enabling the patients to regulate their own slow cortical potentials, and both have made progress in increasing attention and alertness. With summary of several clinical studies with strong evidence, we present cutting edge results from the clinical application of BCI in motor and cognitive diseases, including stroke, spinal cord injury, ALS, and ADHD.
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6
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Functional Electrical Stimulation and Its Use During Cycling for the Rehabilitation of Individuals with Stroke. ACTA ACUST UNITED AC 2018. [DOI: 10.1007/978-3-319-72736-3_21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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7
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Yanev P, Seevinck PR, Rudrapatna US, Bouts MJ, van der Toorn A, Gertz K, Kronenberg G, Endres M, van Tilborg GA, Dijkhuizen RM. Magnetic resonance imaging of local and remote vascular remodelling after experimental stroke. J Cereb Blood Flow Metab 2017; 37:2768-2779. [PMID: 27798270 PMCID: PMC5536787 DOI: 10.1177/0271678x16674737] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The pattern of vascular remodelling in relation to recovery after stroke remains largely unclear. We used steady-state contrast-enhanced magnetic resonance imaging to assess the development of cerebral blood volume and microvascular density in perilesional and exofocal areas from (sub)acutely to chronically after transient stroke in rats. Microvascular density was verified histologically after infusion with Evans Blue dye. At day 1, microvascular cerebral blood volume and microvascular density were reduced in and around the ischemic lesion (intralesional borderzone: microvascular cerebral blood volume = 72 ± 8%; microvascular density = 76 ± 8%) (P < 0.05), while total cerebral blood volume remained relatively unchanged. Perilesional microvascular cerebral blood volume and microvascular density subsequently normalized (day 7) and remained relatively stable (day 70). In remote ipsilateral areas in the thalamus and substantia nigra - not part of the ischemic lesion - microvascular density gradually increased between days 1 and 70 (thalamic ventral posterior nucleus: microvascular density = 119 ± 9%; substantia nigra: microvascular density = 122 ± 8% (P < 0.05)), which was confirmed histologically. Our data indicate that initial microvascular collapse, with maintained collateral flow in larger vessels, is followed by dynamic revascularization in perilesional tissue. Furthermore, progressive neovascularization in non-ischemic connected areas may offset secondary neuronal degeneration and/or contribute to non-neuronal tissue remodelling. The complex spatiotemporal pattern of vascular remodelling, involving regions outside the lesion territory, may be a critical endogenous process to promote post-stroke brain reorganization.
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Affiliation(s)
- Pavel Yanev
- 1 Biomedical MR Imaging and Spectroscopy Group, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Peter R Seevinck
- 1 Biomedical MR Imaging and Spectroscopy Group, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Umesh S Rudrapatna
- 1 Biomedical MR Imaging and Spectroscopy Group, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Mark Jrj Bouts
- 1 Biomedical MR Imaging and Spectroscopy Group, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Annette van der Toorn
- 1 Biomedical MR Imaging and Spectroscopy Group, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Karen Gertz
- 2 Department of Neurology, Charité - Universitaetsmedizin Berlin, Berlin, Germany.,3 Center for Stroke Research Berlin, Charité - Universitaetsmedizin Berlin, Berlin, Germany
| | - Golo Kronenberg
- 2 Department of Neurology, Charité - Universitaetsmedizin Berlin, Berlin, Germany.,4 German Center for Cardiovascular Research (DZHK), Universitaetsmedizin Berlin, Berlin, Germany
| | - Matthias Endres
- 2 Department of Neurology, Charité - Universitaetsmedizin Berlin, Berlin, Germany.,3 Center for Stroke Research Berlin, Charité - Universitaetsmedizin Berlin, Berlin, Germany.,4 German Center for Cardiovascular Research (DZHK), Universitaetsmedizin Berlin, Berlin, Germany.,5 German Center for Neurodegenerative Diseases (DZNE), Universitaetsmedizin Berlin, Berlin, Germany.,6 Berlin Institute of Health (BIH), Berlin, Germany
| | - Geralda A van Tilborg
- 1 Biomedical MR Imaging and Spectroscopy Group, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Rick M Dijkhuizen
- 1 Biomedical MR Imaging and Spectroscopy Group, University Medical Center Utrecht, Utrecht, The Netherlands
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8
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Mouthon AL, Meyer-Heim A, Kurth S, Ringli M, Pugin F, van Hedel HJA, Huber R. High-Density Electroencephalographic Recordings During Sleep in Children and Adolescents With Acquired Brain Injury. Neurorehabil Neural Repair 2017; 31:462-474. [PMID: 28162033 DOI: 10.1177/1545968316688794] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Acquired brain injuries (ABI) such as traumatic brain injury (TBI) or stroke can result in motor, language, or cognitive impairments. Although a considerable number of studies have investigated functional recovery, underlying brain reorganization remains poorly understood. Accumulating evidence indicates that plastic processes in the brain are linked to changes in electroencephalographic (EEG) slow wave activity (SWA) during deep sleep (EEG spectral power 1-4.5 Hz). OBJECTIVE We investigated sleep SWA in children and adolescents with ABI. METHODS We used high-density EEG (128 electrodes) to record sleep in 22 young patients with ABI (age range = 4-16 years). We compared patients to 52 previously measured typically developing children and adolescents (age range = 4-16 years). RESULTS The pattern of alterations in SWA differed between particular patient groups. In patients with bilateral stroke, SWA was globally reduced across the entire scalp. Patients with unilateral stroke showed a local reduction in SWA over lesion areas and an increase over perilesional and contralateral brain areas. In patients with severe TBI, we found a reduction in SWA over the midline and an increase over lateral brain areas. We found no consistent pattern in patients with mild to moderate TBI. CONCLUSIONS Sleep SWA seems to be a sensitive measure to assess individual alterations in neural activity after ABI. Deviations from age norms might indirectly indicate plastic processes that have occurred since injury. Improving our understanding of neural activity after ABI could optimize clinical prognosis and guide the development of novel therapeutic interventions.
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Affiliation(s)
- Anne-Laure Mouthon
- 1 Child Development Center and Pediatric Sleep Disorders Center, University Children's Hospital Zurich, Switzerland.,2 Rehabilitation Center Affoltern am Albis, University Children's Hospital Zurich, Switzerland.,3 Children's Research Center, University Children's Hospital Zurich, Switzerland
| | - Andreas Meyer-Heim
- 2 Rehabilitation Center Affoltern am Albis, University Children's Hospital Zurich, Switzerland.,3 Children's Research Center, University Children's Hospital Zurich, Switzerland
| | - Salome Kurth
- 1 Child Development Center and Pediatric Sleep Disorders Center, University Children's Hospital Zurich, Switzerland.,3 Children's Research Center, University Children's Hospital Zurich, Switzerland.,5 Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Maya Ringli
- 1 Child Development Center and Pediatric Sleep Disorders Center, University Children's Hospital Zurich, Switzerland.,3 Children's Research Center, University Children's Hospital Zurich, Switzerland
| | - Fiona Pugin
- 1 Child Development Center and Pediatric Sleep Disorders Center, University Children's Hospital Zurich, Switzerland.,3 Children's Research Center, University Children's Hospital Zurich, Switzerland
| | - Hubertus J A van Hedel
- 2 Rehabilitation Center Affoltern am Albis, University Children's Hospital Zurich, Switzerland.,3 Children's Research Center, University Children's Hospital Zurich, Switzerland
| | - Reto Huber
- 1 Child Development Center and Pediatric Sleep Disorders Center, University Children's Hospital Zurich, Switzerland.,3 Children's Research Center, University Children's Hospital Zurich, Switzerland.,4 Department of Child and Adolescent Psychiatry and Psychotherapy, Psychiatric Hospital, University of Zurich, Switzerland
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9
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Kiper P, Szczudlik A, Venneri A, Stozek J, Luque-Moreno C, Opara J, Baba A, Agostini M, Turolla A. Computational models and motor learning paradigms: Could they provide insights for neuroplasticity after stroke? An overview. J Neurol Sci 2016; 369:141-148. [PMID: 27653881 DOI: 10.1016/j.jns.2016.08.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 08/08/2016] [Accepted: 08/09/2016] [Indexed: 01/08/2023]
Abstract
Computational approaches for modelling the central nervous system (CNS) aim to develop theories on processes occurring in the brain that allow the transformation of all information needed for the execution of motor acts. Computational models have been proposed in several fields, to interpret not only the CNS functioning, but also its efferent behaviour. Computational model theories can provide insights into neuromuscular and brain function allowing us to reach a deeper understanding of neuroplasticity. Neuroplasticity is the process occurring in the CNS that is able to permanently change both structure and function due to interaction with the external environment. To understand such a complex process several paradigms related to motor learning and computational modeling have been put forward. These paradigms have been explained through several internal model concepts, and supported by neurophysiological and neuroimaging studies. Therefore, it has been possible to make theories about the basis of different learning paradigms according to known computational models. Here we review the computational models and motor learning paradigms used to describe the CNS and neuromuscular functions, as well as their role in the recovery process. These theories have the potential to provide a way to rigorously explain all the potential of CNS learning, providing a basis for future clinical studies.
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Affiliation(s)
- Pawel Kiper
- Laboratory of Kinematics and Robotics, IRCCS San Camillo Hospital Foundation, via Alberoni 70, 30126 Venice, Italy.
| | - Andrzej Szczudlik
- Jagiellonian University Medical College, ul. Sw. Anny 12, 31-008 Krakow, Poland
| | - Annalena Venneri
- Laboratory of Kinematics and Robotics, IRCCS San Camillo Hospital Foundation, via Alberoni 70, 30126 Venice, Italy; Department of Neuroscience, The University of Sheffield, 385a Glossop Road, S10 2HQ Sheffield, UK
| | - Joanna Stozek
- The University of Physical Education, Al. Jana Pawla II 78, 31-571 Krakow, Poland
| | - Carlos Luque-Moreno
- Department of Physical Therapy, The University of Seville, C/Avicena S/N, 41009 Seville, Spain; Motion Analysis Laboratory, Virgen del Rocio Hospital, Avda. Manuel Siurot S/N, 41013 Seville, Spain
| | - Jozef Opara
- Academy of Physical Education, ul. Mikolowska 72a, 40-065 Katowice, Poland
| | - Alfonc Baba
- Laboratory of Kinematics and Robotics, IRCCS San Camillo Hospital Foundation, via Alberoni 70, 30126 Venice, Italy
| | - Michela Agostini
- Laboratory of Kinematics and Robotics, IRCCS San Camillo Hospital Foundation, via Alberoni 70, 30126 Venice, Italy
| | - Andrea Turolla
- Laboratory of Kinematics and Robotics, IRCCS San Camillo Hospital Foundation, via Alberoni 70, 30126 Venice, Italy; Department of Neuroscience, The University of Sheffield, 385a Glossop Road, S10 2HQ Sheffield, UK
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10
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Pagnozzi AM, Dowson N, Fiori S, Doecke J, Bradley AP, Boyd RN, Rose S. Alterations in regional shape on ipsilateral and contralateral cortex contrast in children with unilateral cerebral palsy and are predictive of multiple outcomes. Hum Brain Mapp 2016; 37:3588-603. [PMID: 27259165 DOI: 10.1002/hbm.23262] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 05/04/2016] [Accepted: 05/06/2016] [Indexed: 11/07/2022] Open
Abstract
Congenital brain lesions result in a wide range of cerebral tissue alterations observed in children with cerebral palsy (CP) that are associated with a range of functional impairments. The relationship between injury severity and functional outcomes, however, remains poorly understood. This research investigates the differences in cortical shape between children with congenital brain lesions and typically developing children (TDC) and investigates the correlations between cortical shape and functional outcome in a large cohort of patients diagnosed with unilateral CP. Using 139 structural magnetic resonance images, including 95 patients with clinically diagnosed CP and 44 TDC, cortical segmentations were obtained using a modified expectation maximization algorithm. Three shape characteristics (cortical thickness, curvature, and sulcal depth) were computed within a number of cortical regions. Significant differences in these shape measures compared to the TDC were observed on both the injured hemisphere of children with CP (P < 0.004), as well as on the apparently uninjured hemisphere, illustrating potential compensatory mechanisms in these children. Furthermore, these shape measures were significantly correlated with several functional outcomes, including motor, cognition, vision, and communication (P < 0.012), with three out of these four models performing well on test set validation. This study highlights that cortical neuroplastic effects may be quantified using MR imaging, allowing morphological changes to be studied longitudinally, including any influence of treatment. Ultimately, such approaches could be used for the long term prediction of outcomes and the tailoring of treatment to individuals. Hum Brain Mapp 37:3588-3603, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Alex M Pagnozzi
- CSIRO Health and Biosecurity, The Australian e-Health Research Centre, Brisbane, Australia.,The School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, Australia
| | - Nicholas Dowson
- CSIRO Health and Biosecurity, The Australian e-Health Research Centre, Brisbane, Australia
| | | | - James Doecke
- CSIRO Health and Biosecurity, The Australian e-Health Research Centre, Brisbane, Australia
| | - Andrew P Bradley
- The School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, Australia
| | - Roslyn N Boyd
- School of Medicine, The University of Queensland, Queensland Cerebral Palsy and Rehabilitation Research Centre, Brisbane, Australia
| | - Stephen Rose
- CSIRO Health and Biosecurity, The Australian e-Health Research Centre, Brisbane, Australia
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11
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Paggiaro A, Birbaumer N, Cavinato M, Turco C, Formaggio E, Del Felice A, Masiero S, Piccione F. Magnetoencephalography in Stroke Recovery and Rehabilitation. Front Neurol 2016; 7:35. [PMID: 27065338 PMCID: PMC4815903 DOI: 10.3389/fneur.2016.00035] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 03/04/2016] [Indexed: 01/01/2023] Open
Abstract
Magnetoencephalography (MEG) is a non-invasive neurophysiological technique used to study the cerebral cortex. Currently, MEG is mainly used clinically to localize epileptic foci and eloquent brain areas in order to avoid damage during neurosurgery. MEG might, however, also be of help in monitoring stroke recovery and rehabilitation. This review focuses on experimental use of MEG in neurorehabilitation. MEG has been employed to detect early modifications in neuroplasticity and connectivity, but there is insufficient evidence as to whether these methods are sensitive enough to be used as a clinical diagnostic test. MEG has also been exploited to derive the relationship between brain activity and movement kinematics for a motor-based brain–computer interface. In the current body of experimental research, MEG appears to be a powerful tool in neurorehabilitation, but it is necessary to produce new data to confirm its clinical utility.
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Affiliation(s)
- Andrea Paggiaro
- Laboratory of Neurophysiology and Magnetoencephalography, Department of Neurophysiology, Institute of Care and Research, S.Camillo Hospital Foundation , Venice , Italy
| | - Niels Birbaumer
- Laboratory of Neurophysiology and Magnetoencephalography, Department of Neurophysiology, Institute of Care and Research, S.Camillo Hospital Foundation, Venice, Italy; Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
| | - Marianna Cavinato
- Laboratory of Neurophysiology and Magnetoencephalography, Department of Neurophysiology, Institute of Care and Research, S.Camillo Hospital Foundation , Venice , Italy
| | - Cristina Turco
- Laboratory of Neurophysiology and Magnetoencephalography, Department of Neurophysiology, Institute of Care and Research, S.Camillo Hospital Foundation , Venice , Italy
| | - Emanuela Formaggio
- Laboratory of Neurophysiology and Magnetoencephalography, Department of Neurophysiology, Institute of Care and Research, S.Camillo Hospital Foundation , Venice , Italy
| | - Alessandra Del Felice
- Section of Rehabilitation, Department of Neuroscience, University of Padova , Padova , Italy
| | - Stefano Masiero
- Section of Rehabilitation, Department of Neuroscience, University of Padova , Padova , Italy
| | - Francesco Piccione
- Laboratory of Neurophysiology and Magnetoencephalography, Department of Neurophysiology, Institute of Care and Research, S.Camillo Hospital Foundation , Venice , Italy
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12
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Huynh W, Vucic S, Krishnan AV, Lin CSY, Kiernan MC. Exploring the Evolution of Cortical Excitability Following Acute Stroke. Neurorehabil Neural Repair 2015; 30:244-57. [PMID: 26150146 DOI: 10.1177/1545968315593804] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND Evolution of changes in intracortical excitability following stroke, particularly in the contralesional hemisphere, is being increasingly recognized in relation to maximizing the potential for functional recovery. OBJECTIVE The present study utilized a prospective longitudinal design over a 12-month period from stroke onset, to investigate the evolution of intracortical excitability involving both motor cortices and their relationship to recovery, and whether such changes were influenced by baseline stroke characteristics. METHODS Thirty-one patients with acute unilateral ischemic stroke were recruited from a tertiary hospital stroke unit. Comprehensive clinical assessments and cortical excitability were undertaken at stroke onset using a novel threshold-tracking paired-pulse transcranial magnetic stimulation technique, and repeated at 3-, 6-, and 12-month follow-up in 17 patients who completed the longitudinal assessment. RESULTS Shortly following stroke, short-interval intracortical inhibition (SICI) was significantly reduced in both lesioned and contralesional hemispheres that correlated with degree of recovery over the subsequent 3 months. Over the follow-up period, ipsilesional SICI remained reduced in all patient groups, while SICI over the contralesional hemisphere remained reduced only in the groups with cortical stroke or more baseline functional impairment. CONCLUSIONS The current study has demonstrated that evolution of intracortical excitability, particularly over the contralesional hemisphere, may vary between patients with differing baseline stroke and clinical characteristics, suggesting that ongoing contralesional network recruitment may be necessary for those patients who have significant disruptions to the integrity of ipsilesional motor pathways. Results from the present series have implications for the development of neuromodulatory brain stimulation protocols to harness and thereby facilitate stroke recovery.
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Affiliation(s)
- William Huynh
- Brain and Mind Research Institute, University of Sydney, New South Wales, Australia Prince of Wales Clinical School, University of New South Wales, New South Wales, Australia
| | - Steve Vucic
- Western Clinical School, University of Sydney, New South Wales, Australia
| | - Arun V Krishnan
- Prince of Wales Clinical School, University of New South Wales, New South Wales, Australia
| | - Cindy S-Y Lin
- University of New South Wales, New South Wales, Australia
| | - Matthew C Kiernan
- Brain and Mind Research Institute, University of Sydney, New South Wales, Australia
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Models of care for late-life depression of the medically ill: examples from chronic obstructive pulmonary disease and stroke. Am J Geriatr Psychiatry 2015; 23:477-87. [PMID: 25028344 PMCID: PMC4272675 DOI: 10.1016/j.jagp.2014.06.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 05/19/2014] [Accepted: 06/07/2014] [Indexed: 11/22/2022]
Abstract
Depression worsens most treatment outcomes in medically ill older adults. Chronic medical illnesses weaken and demoralize patients and compromise their ability to adhere to treatments requiring consistency and effort. Acute medical illnesses create a psychosocial storm that finds patients and their ecosystem unprepared. We describe two intervention models that can be used to target and personalize treatment in depressed, chronically, or acutely medically ill older adults. The Personalized Adherence Intervention for Depression and COPD (PID-C) is a model intervention for depressed patients with chronic medical illnesses. It targets patient-specific barriers to treatment engagement and aims to shift the balance in favor of treatment participation. PID-C led to higher remission rates of depression, reduction in depressive symptoms, and reduction in dyspnea-related disability. The addition of problem-solving training enables patients to use resources available to them and hopefully improve their outcomes. Ecosystem-focused therapy (EFT) is a model intervention for depression developing in the context of an acute medical event. It was developed for patients with poststroke depression (PSD) and targets five areas, part of the "psychosocial storm" originating from the patient's sudden disability and the resulting change in the patient's needs and family's life. A preliminary study suggests that EFT is feasible and efficacious in reducing depressive symptoms and signs and disability in PSD.
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Fischer HC, Stubblefield K, Kline T, Luo X, Kenyon RV, Kamper DG. Hand Rehabilitation Following Stroke: A Pilot Study of Assisted Finger Extension Training in a Virtual Environment. Top Stroke Rehabil 2014; 14:1-12. [PMID: 17311785 DOI: 10.1310/tsr1401-1] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND AND PURPOSE The purpose of this pilot study was to investigate the impact of assisted motor training in a virtual environment on hand function in stroke survivors. PARTICIPANTS Fifteen volunteer stroke survivors (32-88 years old) with chronic upper extremity hemiparesis (1-38 years post incident) took part. METHOD Participants had 6 weeks of training in reach-to-grasp of virtual and actual objects. They were randomized to one of three groups: assistance of digit extension provided by a novel cable orthosis, assistance provided by a novel pneumatic orthosis, or no assistance provided. Hand performance was evaluated at baseline, immediately following training, and 1 month after completion of training. Clinical assessments included the Wolf Motor Function Test (WMFT), Box and Blocks Test (BB), Upper Extremity Fugl-Meyer Test (FM), and Rancho Los Amigos Functional Test of the Hemiparetic Upper Extremity (RLA). Biomechanical assessments included grip strength, extension range of motion and velocity, spasticity, and isometric strength. RESULTS Participants demonstrated a significant decrease in time to perform functional tasks for the WMFT (p = .02), an increase in the number of blocks successfully grasped and released during the BB (p = .09), and an increase for the FM score (p = .08). There were no statistically significant changes in time to complete tasks on the RLA or any of the biomechanical measures. Assistance of extension did not have a significant effect. DISCUSSION AND CONCLUSION After the training period, participants in all 3 groups demonstrated a decrease in time to perform some of the functional tasks. Although the overall gains were slight, the general acceptance of the novel rehabilitation tools by a population with substantial impairment suggests that a larger randomized controlled trial, potentially in a subacute population, may be warranted.
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Affiliation(s)
- Heidi C Fischer
- Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, Illinois, USA
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Triandafilou KM, Kamper DG. Carryover effects of cyclical stretching of the digits on hand function in stroke survivors. Arch Phys Med Rehabil 2014; 95:1571-6. [PMID: 24794423 DOI: 10.1016/j.apmr.2014.04.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Revised: 04/10/2014] [Accepted: 04/19/2014] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To investigate the longevity and cumulative impact of multiple sessions of passive, cyclical stretching of the digits on hand function in subacute stroke survivors. DESIGN Before-after trial with intervention repeated on 3 consecutive days. SETTING Research laboratory. PARTICIPANTS Individuals (N=27) with moderate to severe hand impairment, 2 to 6 months (subacute, n=12) and >7 months (chronic, n=15) poststroke. INTERVENTIONS Subjects wore an actuated glove orthosis that cyclically moved their fingers and thumb from a relaxed/flexed posture into neutral extension for 30 minutes on 3 consecutive days. MAIN OUTCOME MEASURES Three hand-specific tasks from the Graded Wolf Motor Function Test, Box and Block Test (BBT), grip strength, and lateral pinch strength. Recordings were taken before stretching and at 3 time points, each separated by 30 minutes after completion of stretching on each day. RESULTS Significant improvement was observed immediately after the stretching for both groups. Improvements in the subacute group were largely maintained up to 1 hour poststretching, with significant carryover from day to day for some outcomes measures such as the BBT (P=.006) and grip strength (P=.012). In contrast, improvements after stretching for the chronic group were transient, with the changes largely dissipating over time and no significant cumulative effect across days. CONCLUSIONS Cyclical stretching of the digits had a lasting and reinforcing effect on improving hand motor control for subacute stroke survivors. Incorporation of cyclical stretching before active hand therapy may prove to be a beneficial treatment for stroke survivors, especially during the subacute phase of recovery.
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Affiliation(s)
| | - Derek G Kamper
- Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, IL; Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL
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Reinforced feedback in virtual environment for rehabilitation of upper extremity dysfunction after stroke: preliminary data from a randomized controlled trial. BIOMED RESEARCH INTERNATIONAL 2014; 2014:752128. [PMID: 24745024 PMCID: PMC3972918 DOI: 10.1155/2014/752128] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 02/01/2014] [Accepted: 02/10/2014] [Indexed: 01/30/2023]
Abstract
Objectives. To study whether the reinforced feedback in virtual environment (RFVE) is more effective than traditional rehabilitation (TR) for the treatment of upper limb motor function after stroke, regardless of stroke etiology (i.e., ischemic, hemorrhagic). Design. Randomized controlled trial. Participants. Forty-four patients affected by stroke. Intervention. The patients were randomized into two groups: RFVE (N = 23) and TR (N = 21), and stratified according to stroke etiology. The RFVE treatment consisted of multidirectional exercises providing augmented feedback provided by virtual reality, while in the TR treatment the same exercises were provided without augmented feedbacks. Outcome Measures. Fugl-Meyer upper extremity scale (F-M UE), Functional Independence Measure scale (FIM), and kinematics parameters (speed, time, and peak). Results. The F-M UE (P = 0.030), FIM (P = 0.021), time (P = 0.008), and peak (P = 0.018), were significantly higher in the RFVE group after treatment, but not speed (P = 0.140). The patients affected by hemorrhagic stroke significantly improved FIM (P = 0.031), time (P = 0.011), and peak (P = 0.020) after treatment, whereas the patients affected by ischemic stroke improved significantly only speed (P = 0.005) when treated by RFVE. Conclusion. These results indicated that some poststroke patients may benefit from RFVE program for the recovery of upper limb motor function. This trial is registered with NCT01955291.
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Rea M, Rana M, Lugato N, Terekhin P, Gizzi L, Brötz D, Fallgatter A, Birbaumer N, Sitaram R, Caria A. Lower Limb Movement Preparation in Chronic Stroke: A Pilot Study Toward an fNIRS-BCI for Gait Rehabilitation. Neurorehabil Neural Repair 2014; 28:564-75. [PMID: 24482298 DOI: 10.1177/1545968313520410] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Background Thus far, most of the brain-computer interfaces (BCIs) developed for motor rehabilitation used electroencephalographic signals to drive prostheses that support upper limb movement. Only few BCIs used hemodynamic signals or were designed to control lower extremity prostheses. Recent technological developments indicate that functional near-infrared spectroscopy (fNIRS)-BCI can be exploited in rehabilitation of lower limb movement due to its great usability and reduced sensitivity to head motion artifacts. Objective The aim of this proof of concept study was to assess whether hemodynamic signals underlying lower limb motor preparation in stroke patients can be reliably measured and classified. Methods fNIRS data were acquired during preparation of left and right hip movement in 7 chronic stroke patients. Results Single-trial analysis indicated that specific hemodynamic changes associated with left and right hip movement preparation can be measured with fNIRS. Linear discriminant analysis classification of totHB signal changes in the premotor cortex and/or posterior parietal cortex indicated above chance accuracy in discriminating paretic from nonparetic movement preparation trials in most of the tested patients. Conclusion The results provide first evidence that fNIRS can detect brain activity associated with single-trial lower limb motor preparation in stroke patients. These findings encourage further investigation of fNIRS suitability for BCI applications in rehabilitation of patients with lower limb motor impairment after stroke.
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Affiliation(s)
- Massimiliano Rea
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany Department of General Psychiatry, University of Tübingen, Tübingen, Germany
| | - Mohit Rana
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
| | - Nicola Lugato
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
| | - Pavel Terekhin
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
| | | | - Doris Brötz
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
| | - Andreas Fallgatter
- Department of General Psychiatry, University of Tübingen, Tübingen, Germany
| | - Niels Birbaumer
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany Istituto di Ricovero e Cura a Carattere Scientifico, Venezia, Lido, Italy
| | - Ranganatha Sitaram
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany University of Florida, Gainesville, FL, USA Sri Chitra Tirunal Institute of Medical Sciences and Technology, Trivandrum, India
| | - Andrea Caria
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany Istituto di Ricovero e Cura a Carattere Scientifico, Venezia, Lido, Italy
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Sensorimotor Cortex Reorganization in Alzheimer's Disease and Metal Dysfunction: A MEG Study. Int J Alzheimers Dis 2013; 2013:638312. [PMID: 24416615 PMCID: PMC3876721 DOI: 10.1155/2013/638312] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 10/04/2013] [Indexed: 11/17/2022] Open
Abstract
Objective. To verify whether systemic biometals dysfunctions affect neurotransmission in living Alzheimer's disease (AD) patients. Methods. We performed a case-control study using magnetoencephalography to detect sensorimotor fields of AD patients, at rest and during median nerve stimulation. We analyzed position and amount of neurons synchronously activated by the stimulation in both hemispheres to investigate the capability of the primary somatosensory cortex to reorganize its circuitry disrupted by the disease. We also assessed systemic levels of copper, ceruloplasmin, non-Cp copper (i.e., copper not bound to ceruloplasmin), peroxides, transferrin, and total antioxidant capacity. Results. Patients' sensorimotor generators appeared spatially shifted, despite no change of latency and strength, while spontaneous activity sources appeared unchanged. Neuronal reorganization was greater in moderately ill patients, while delta activity increased in severe patients. Non-Cp copper was the only biological variable appearing to be associated with patient sensorimotor transmission. Conclusions. Our data strengthen the notion that non-Cp copper, not copper in general, affects neuronal activity in AD. Significance. High plasticity in the disease early stages in regions controlling more commonly used body parts strengthens the notion that physical and cognitive activities are protective factors against progression of dementia.
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von Carlowitz-Ghori K, Bayraktaroglu Z, Hohlefeld FU, Losch F, Curio G, Nikulin VV. Corticomuscular coherence in acute and chronic stroke. Clin Neurophysiol 2013; 125:1182-91. [PMID: 24315544 DOI: 10.1016/j.clinph.2013.11.006] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 10/23/2013] [Accepted: 11/05/2013] [Indexed: 01/25/2023]
Abstract
OBJECTIVE Motor recovery after stroke is attributed to neuronal plasticity, however not all post-stroke neuronal changes relate to regaining fine motor control. Corticomuscular coherence (CMC) is a measure allowing to trace neuronal reorganizations which are functionally relevant for motor recovery. Contrary to previous studies which were performed only in chronic stage, we measured CMC in patients with stroke at both acute and chronic stroke stages. METHODS For the detection of CMC we used multichannel EEG and EMG recordings along with an optimization algorithm for the detection of corticomuscular interactions. RESULTS In acute stroke, the CMC amplitude was larger on the unaffected side compared to the affected side and also larger compared to the unaffected side in the chronic period. Additionally, CMC peak frequencies on both sides decreased in the acute compared to the chronic period and to control subjects. In chronic stage, there were no inter-hemispheric or group differences in CMC amplitude or frequency. CONCLUSIONS The changes in CMC parameters in acute stroke could result from a temporary decrease in inhibition, which normalizes in the course of recovery. As all patients showed very good motor recovery, the modulation of CMC amplitude and frequency over time might thus reflect the process of motor recovery. SIGNIFICANCE We demonstrate for the first time the dynamical changes of corticomuscular interaction both at acute and chronic stage of stroke.
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Affiliation(s)
- Katherina von Carlowitz-Ghori
- Neurophysics Group, Department of Neurology, Charité - University Medicine Berlin, Germany; Institute of Science and Ethics, University of Bonn, Germany; Department of Software Engineering and Theoretical Computer Science, Berlin Institute of Technology, Berlin, Germany
| | - Zubeyir Bayraktaroglu
- Neurophysics Group, Department of Neurology, Charité - University Medicine Berlin, Germany; Center for Stroke Research Berlin, Charité - University Medicine Berlin, Germany
| | - Friederike U Hohlefeld
- Neurophysics Group, Department of Neurology, Charité - University Medicine Berlin, Germany
| | - Florian Losch
- Neurophysics Group, Department of Neurology, Charité - University Medicine Berlin, Germany
| | - Gabriel Curio
- Neurophysics Group, Department of Neurology, Charité - University Medicine Berlin, Germany; Center for Stroke Research Berlin, Charité - University Medicine Berlin, Germany; Bernstein Center for Computational Neuroscience, Berlin, Germany
| | - Vadim V Nikulin
- Neurophysics Group, Department of Neurology, Charité - University Medicine Berlin, Germany; Center for Stroke Research Berlin, Charité - University Medicine Berlin, Germany; Bernstein Center for Computational Neuroscience, Berlin, Germany.
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20
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Alexopoulos GS, Wilkins V, Marino P, Kanellopoulos D, Reding M, Sirey JA, Raue P, Ghosh S, O’Dell MW, Kiosses DN. Ecosystem focused therapy in poststroke depression: a preliminary study. Int J Geriatr Psychiatry 2012; 27:1053-60. [PMID: 22249997 PMCID: PMC3361524 DOI: 10.1002/gps.2822] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Accepted: 10/20/2011] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Poststroke depression (PSD) occurs in the context of abrupt, often catastrophic disability that finds the patient and his or her family unprepared. We developed the ecosystem focused therapy (EFT), a systematic intervention aimed to increase the PSD patient's and his or her ecosystem's abilities to address the "psychosocial storm" of PSD and utilize available treatments effectively and efficiently. This is a preliminary study of its efficacy. DESIGN A total of 24 PSD patients were randomly assigned to receive weekly sessions of EFT or a comparison condition consisting of systematic Education on Stroke and Depression and their treatment for 12 weeks. RESULTS Ecosystem Focused Therapy may be more efficacious than Education on Stroke and Depression in reducing depressive symptoms and signs, in leading to a higher remission rate, and in ameliorating disability in PSD. Reduction of disability in the early part of the trial mediated later improvement in depressive symptomatology. Similarly, reduction in depressive symptoms and signs early on mediated later improvement in disability. CONCLUSION These encouraging findings require replication. Beyond its potential direct benefits in PSD, EFT may provide an appropriate context for efficient and timely administration of pharmacotherapy and of physical, speech, and occupational therapy thus maximizing their efficacy.
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Affiliation(s)
| | | | | | | | - Michael Reding
- Weill-Cornell Medical College,Burke Rehabilitation Hospital
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Akinwuntan AE, Wachtel J, Rosen PN. Driving Simulation for Evaluation and Rehabilitation of Driving After Stroke. J Stroke Cerebrovasc Dis 2012; 21:478-86. [DOI: 10.1016/j.jstrokecerebrovasdis.2010.12.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Accepted: 12/02/2010] [Indexed: 01/27/2023] Open
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Villamar MF, Santos Portilla A, Fregni F, Zafonte R. Noninvasive brain stimulation to modulate neuroplasticity in traumatic brain injury. Neuromodulation 2012; 15:326-38. [PMID: 22882244 DOI: 10.1111/j.1525-1403.2012.00474.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
OBJECTIVE To review the use of noninvasive brain stimulation (NBS) as a therapeutic tool to enhance neuroplasticity following traumatic brain injury (TBI). MATERIALS AND METHODS Based on a literature search, we describe the pathophysiological events following TBI and the rationale for the use of transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) in this setting. RESULTS The pathophysiological mechanisms occurring after TBI vary across time and therefore require differential interventions. Theoretically, given the neurophysiological effects of both TMS and tDCS, these tools may: 1) decrease cortical hyperexcitability acutely after TBI; 2) modulate long-term synaptic plasticity as to avoid maladaptive consequences; and 3) combined with physical and behavioral therapy, facilitate cortical reorganization and consolidation of learning in specific neural networks. All of these interventions may help decrease the burden of disabling sequelae after brain injury. CONCLUSIONS Evidence from animal and human studies reveals the potential benefit of NBS in decreasing the extent of injury and enhancing plastic changes to facilitate learning and recovery of function in lesioned neural tissue. However, this evidence is mainly theoretical at this point. Given safety constraints, studies in TBI patients are necessary to address the role of NBS in this condition as well as to further elucidate its therapeutic effects and define optimal stimulation parameters.
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Affiliation(s)
- Mauricio Fernando Villamar
- Laboratory of Neuromodulation, Department of Physical Medicine & Rehabilitation, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
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Gordon AL, di Maggio A. Rehabilitation for children after acquired brain injury: current and emerging approaches. Pediatr Neurol 2012; 46:339-44. [PMID: 22633627 DOI: 10.1016/j.pediatrneurol.2012.02.029] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Accepted: 02/23/2012] [Indexed: 11/26/2022]
Abstract
Evidence is emerging of diverse, chronic, cumulative disabilities experienced by children in the months and years after acquired brain injury. The long-held assumption that younger children recover better from brain injury than older children or adults has been challenged by recent studies. Populations with acquired brain injury include children with traumatic brain injury and stroke, and a proportion of children with cerebral palsy. Although characteristics of brain injury in children vary, subgroups of this population offer the potential to inform our understanding of developing brain structure-function relationships in response to intervention. Limited evidence and few controlled rehabilitation trials exist regarding children with neurologic conditions. A number of rehabilitation approaches produced benefits in adult stroke, and cerebral palsy populations may be applied to children with other acquired brain injuries. Rehabilitation approaches that have been applied to children with acquired brain injuries, or hold promise for future applications, are reviewed.
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Affiliation(s)
- Anne L Gordon
- Department of Paediatric Neuroscience, Evelina Children's Hospital, King's Health Partners, London, United Kingdom.
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Ishkanian AA, McCullough-Hicks ME, Appelboom G, Piazza MA, Hwang BY, Bruce SS, Hannan LM, Connolly ES, Lavine SD, Meyers PM. Improving patient selection for endovascular treatment of acute cerebral ischemia: a review of the literature and an external validation of the Houston IAT and THRIVE predictive scoring systems. Neurosurg Focus 2012; 30:E7. [PMID: 21631231 DOI: 10.3171/2011.3.focus1144] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Outcome after intraarterial therapy (IAT) for acute ischemic stroke remains variable, suggesting that improved patient selection is needed to better identify patients likely to benefit from treatment. The authors evaluate the predictive accuracies of the Houston IAT (HIAT) and the Totaled Health Risks in Vascular Events (THRIVE) scores in an independent cohort and review the existing literature detailing additional predictive factors to be used in patient selection for IAT. They reviewed their center's endovascular records from January 2004 to July 2010 and identified patients who had acute ischemic stroke and underwent IAT. They calculated individual HIAT and THRIVE scores using patient age, admission National Institutes of Health Stroke Scale (NIHSS) score, admission glucose level, and medical history. The scores' predictive accuracies for good outcome (discharge modified Rankin Scale score ≤ 3) were analyzed using receiver operating characteristics analysis. The THRIVE score predicts poor outcome after IAT with reasonable accuracy and may perform better than the HIAT score. Nevertheless, both measures may have significant clinical utility; further validation in larger cohorts that accounts for differences in patient demographic characteristics, variation in time-to-treatment, and center preferences with respect to IAT modalities is needed. Additional patient predictive factors have been reported but not yet incorporated into predictive scales; the authors suggest the need for additional data analysis to determine the independent predictive value of patient admission NIHSS score, age, admission hyperglycemia, patient comorbidities, thrombus burden, collateral flow, time to treatment, and baseline neuroimaging findings.
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Affiliation(s)
- Amy A Ishkanian
- Department of Neurological Surgery, Columbia University College of Physicians and Surgeons, New York, New York, USA
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Yoon KJ, Oh BM, Kim DY. Functional improvement and neuroplastic effects of anodal transcranial direct current stimulation (tDCS) delivered 1 day vs. 1 week after cerebral ischemia in rats. Brain Res 2012; 1452:61-72. [PMID: 22444278 DOI: 10.1016/j.brainres.2012.02.062] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Revised: 02/23/2012] [Accepted: 02/25/2012] [Indexed: 01/13/2023]
Abstract
Transcranial direct current stimulation (tDCS) is an emerging tool for improving recovery from stroke. However, there has been no trial to determine whether it has a therapeutic benefit in the early stage of cerebral ischemia, and there is no consensus on the optimal time window of stimulation. Here, we described the effects of anodal tDCS in early cerebral ischemia, assessing functional improvements and changes in neuronal plasticity, and identifying the optimal time window for delivering tDCS to maximize functional gains. Thirty rats were randomly assigned to three groups: sham (n=10); early tDCS (ET), receiving tDCS 1day after ischemia for 5 days (n=10), and late tDCS (LT), receiving tDCS 1 week after ischemia for 5 days (n=10). Both ET and LT groups showed improved Barnes maze performance and motor behavioral index scores. However, only the LT group exhibited improvement in beam balance test. Immunohistochemical stainings showed that the ET group reinforced notable MAP-2 expression and the LT group enhanced mainly the level of GAP-43 in both peri-lesional and contralesional cortex. These immunohistochemical results had significant correlation with behavioral and cognitive functions. However, brain MRI and (1)H MRS showed no significant differences among the three groups in ischemic volume and metabolic alteration. These results suggest that anodal tDCS has the potential to modulate neural plasticity around the ischemic penumbra and even in the contralesional area without aggravating infarction volume and metabolic alteration. The degree of functional improvement was slightly greater when tDCS was applied 1 week rather than 1 day after ischemic injury.
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Affiliation(s)
- Kyung Jae Yoon
- Department of Rehabilitation Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Republic of Korea
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Functional MRI and diffusion tensor imaging of brain reorganization after experimental stroke. Transl Stroke Res 2012; 3:36-43. [PMID: 22408692 PMCID: PMC3284658 DOI: 10.1007/s12975-011-0143-8] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Revised: 12/23/2011] [Accepted: 12/27/2011] [Indexed: 11/27/2022]
Abstract
The potential of the adult brain to reorganize after ischemic injury is critical for functional recovery and provides a significant target for therapeutic strategies to promote brain repair. Despite the accumulating evidence of brain plasticity, the interaction and significance of morphological and physiological modifications in post-stroke brain tissue remain mostly unclear. Neuroimaging techniques such as functional MRI (fMRI) and diffusion tensor imaging (DTI) enable in vivo assessment of the spatial and temporal pattern of functional and structural changes inside and outside ischemic lesion areas. This can contribute to the elucidation of critical aspects in post-stroke brain remodeling. Task/stimulus-related fMRI, resting-state fMRI, or pharmacological MRI enables direct or indirect measurement of neuronal activation, functional connectivity, or neurotransmitter system responses, respectively. DTI allows estimation of the structural integrity and connectivity of white matter tracts. Together, these MRI methods provide an unprecedented means to (a) measure longitudinal changes in tissue structure and function close by and remote from ischemic lesion areas, (b) evaluate the organizational profile of neural networks after stroke, and (c) identify degenerative and restorative processes that affect post-stroke functional outcome. Besides, the availability of MRI in clinical institutions as well as research laboratories provides an optimal basis for translational research on stroke recovery. This review gives an overview of the current status and perspectives of fMRI and DTI applications to study brain reorganization in experimental stroke models.
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Vuong J, Henderson AK, Tuor UI, Dunn JF, Teskey GC. Persistent enhancement of functional MRI responsiveness to sensory stimulation following repeated seizures. Epilepsia 2011; 52:2285-92. [PMID: 22091536 DOI: 10.1111/j.1528-1167.2011.03317.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
PURPOSE Neural reorganization and interictal behavioral anomalies have been documented in people with epilepsy and in animal seizure models. Alterations in behavior could be due to somatosensory dysfunction. This study was designed to determine whether seizures can lead to changes in somatosensory representations and whether those changes are persistent. METHODS Twice-daily seizures were elicited by delivering 1 s of electrical stimulation through carbon fiber electrodes implanted in both the corpus callosum and sensorimotor neocortex of young adult male Long-Evans rats until a total of 20 seizures were elicited. Either 1-3 days or 3-5 weeks following the last seizure, functional magnetic resonance imaging (MRI) was used to image the brain during electrical stimulation of each forepaw independently. KEY FINDINGS Forepaw stimulation in control rats resulted in a focused and contralateral fMRI signal in the somatosensory neocortex. Rats that had repeated seizures had a 151% increase in the number of voxels activated in the contralateral hemisphere 1-3 days after the last seizure and a 166% increase at 3-5 weeks after the last seizure. The number of voxels activated in response to forepaw stimulation was positively correlated with the duration of the longest seizure experienced by each rat. The intensity of the activated voxels was not significantly increased at either time interval from the last seizure. SIGNIFICANCE The increased area of activation in somatosensory cortex, which is persistent at 3-5 weeks, is consistent with previous observations of larger motor maps following seizures. Seizure-induced changes in the functioning of sensory cortex may also contribute to interictal behavioral anomalies.
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Affiliation(s)
- Jennifer Vuong
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
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Albert SJ, Kesselring J. Neurorehabilitation of stroke. J Neurol 2011; 259:817-32. [PMID: 21964750 DOI: 10.1007/s00415-011-6247-y] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 09/04/2011] [Accepted: 09/08/2011] [Indexed: 10/17/2022]
Abstract
Despite ongoing improvements in the acute treatment of cerebrovascular diseases and organization of stroke services, many stroke survivors are in need of neurorehabilitation, as more than two-thirds show persisting neurologic deficits. While early elements of neurorehabilitation are already taking place on the stroke unit, after the acute treatment, the patient with relevant neurologic deficits usually takes part in an organized inpatient multidisciplinary rehabilitation program and eventually continues with therapies in an ambulatory setting afterwards. A specialized multidisciplinary neurorehabilitation team with structured organization and processes provides a multimodal, intense treatment program for stroke patients which is adapted in detail to the individual goals of rehabilitation. There are many parallels between postlesional neuroplasticity (relearning) and learning in the development of individuals as well as task learning of healthy persons. One key principle of neurorehabilitation is the repetitive creation of specific learning situations to promote mechanisms of neural plasticity in stroke recovery. There is evidence of achieving a better outcome of neurorehabilitation with early initiation of treatment, high intensity, with specific goals and active therapies, and the coordinated work and multimodality of a specialized team. In this context, interdisciplinary goal-setting and regular assessments of the patient are important. Furthermore, several further potential enhancers of neural plasticity, e.g., peripheral and brain stimulation techniques, pharmacological augmentation, and use of robotics, are under evaluation.
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Affiliation(s)
- Sylvan J Albert
- Department of Neurology and Neurorehabilitation, Rehabilitation Center, 7317, Valens, Switzerland.
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Carter AR, Patel KR, Astafiev SV, Snyder AZ, Rengachary J, Strube MJ, Pope A, Shimony JS, Lang CE, Shulman GL, Corbetta M. Upstream dysfunction of somatomotor functional connectivity after corticospinal damage in stroke. Neurorehabil Neural Repair 2011; 26:7-19. [PMID: 21803932 DOI: 10.1177/1545968311411054] [Citation(s) in RCA: 157] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Recent studies have shown that focal injuries can have remote effects on network function that affect behavior, but these network-wide repercussions are poorly understood. OBJECTIVE This study tested the hypothesis that lesions specifically to the outflow tract of a distributed network can result in upstream dysfunction in structurally intact portions of the network. In the somatomotor system, this upstream dysfunction hypothesis predicted that lesions of the corticospinal tract might be associated with functional disruption within the system. Motor impairment might then reflect the dual contribution of corticospinal damage and altered network functional connectivity. METHODS A total of 23 subacute stroke patients and 13 healthy controls participated in the study. Corticospinal tract damage was quantified using a template of the tract generated from diffusion tensor imaging in healthy controls. Somatomotor network functional integrity was determined by resting state functional connectivity magnetic resonance imaging. RESULTS The extent of corticospinal damage was negatively correlated with interhemispheric resting functional connectivity, in particular with connectivity between the left and right central sulcus. Although corticospinal damage accounted for much of the variance in motor performance, the behavioral impact of resting connectivity was greater in subjects with mild or moderate corticospinal damage and less in those with severe corticospinal damage. CONCLUSIONS Our results demonstrated that dysfunction of cortical functional connectivity can occur after interruption of corticospinal outflow tracts and can contribute to impaired motor performance. Recognition of these secondary effects from a focal lesion is essential for understanding brain-behavior relationships after injury, and they may have important implications for neurorehabilitation.
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Affiliation(s)
- Alex R Carter
- Department of Neurology, Washington University School of Medicine, St Louis, MO 63110, USA.
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Anderson V, Spencer-Smith M, Wood A. Do children really recover better? Neurobehavioural plasticity after early brain insult. Brain 2011; 134:2197-221. [PMID: 21784775 DOI: 10.1093/brain/awr103] [Citation(s) in RCA: 337] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Affiliation(s)
- Vicki Anderson
- Department of Psychology, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
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Ishibashi R, Lambon Ralph MA, Saito S, Pobric G. Different roles of lateral anterior temporal lobe and inferior parietal lobule in coding function and manipulation tool knowledge: evidence from an rTMS study. Neuropsychologia 2011; 49:1128-1135. [PMID: 21219917 DOI: 10.1016/j.neuropsychologia.2011.01.004] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Revised: 12/15/2010] [Accepted: 01/04/2011] [Indexed: 10/18/2022]
Abstract
A remarkable cognitive ability in humans is the competency to use a wide variety of different tools. Two cortical regions, the anterior temporal lobes (ATL) and left inferior parietal lobule (IPL), have been proposed to make differential contributions to two kinds of knowledge about tools - function vs. manipulation. We used repetitive transcranial magnetic stimulation (rTMS) and two semantic decision tasks to assess the role of these regions in healthy participants. Participants made semantic decisions about the function (what for) or manipulation (how) of tools used in daily life. The stimulation of ATL resulted in longer responses for the "function" judgments, whilst stimulation of IPL yielded longer responses for the "manipulation" judgments. In line with the neuropsychological literature, these results are discussed within hub-and-spoke framework of semantic memory.
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Affiliation(s)
- Ryo Ishibashi
- Department of Cognitive Psychology in Education, Kyoto University, Japan; Neuroscience and Aphasia Research Unit, University of Manchester, UK
| | | | - Satoru Saito
- Department of Cognitive Psychology in Education, Kyoto University, Japan; Neuroscience and Aphasia Research Unit, University of Manchester, UK
| | - Gorana Pobric
- Neuroscience and Aphasia Research Unit, University of Manchester, UK.
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Kiper P, Piron L, Turolla A, Stożek J, Tonin P. The effectiveness of reinforced feedback in virtual environment in the first 12 months after stroke. Neurol Neurochir Pol 2011; 45:436-44. [DOI: 10.1016/s0028-3843(14)60311-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Barthélemy D, Grey MJ, Nielsen JB, Bouyer L. Involvement of the corticospinal tract in the control of human gait. PROGRESS IN BRAIN RESEARCH 2011; 192:181-97. [PMID: 21763526 DOI: 10.1016/b978-0-444-53355-5.00012-9] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Given the inherent mechanical complexity of human bipedal locomotion, and that complete spinal cord lesions in human leads to paralysis with no recovery of gait, it is often suggested that the corticospinal tract (CST) has a more predominant role in the control of walking in humans than in other animals. However, what do we actually know about the contribution of the CST to the control of gait? This chapter will provide an overview of this topic based on the premise that a better understanding of the role of the CST in gait will be essential for the design of evidence-based approaches to rehabilitation therapy, which will enhance gait ability and recovery in patients with lesions to the central nervous system (CNS). We review evidence for the involvement of the primary motor cortex and the CST during normal and perturbed walking and during gait adaptation. We will also discuss knowledge on the CST that has been gained from studies involving CNS lesions, with a particular focus on recent data acquired in people with spinal cord injury.
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Affiliation(s)
- Dorothy Barthélemy
- School of Rehabilitation, Faculty of Medicine, Université de Montréal, Montréal, Québec, Canada.
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Virtual reality-enhanced partial body weight-supported treadmill training poststroke: feasibility and effectiveness in 6 subjects. Arch Phys Med Rehabil 2010; 91:115-22. [PMID: 20103405 DOI: 10.1016/j.apmr.2009.09.009] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Accepted: 09/01/2009] [Indexed: 01/12/2023]
Abstract
UNLABELLED Walker ML, Ringleb SI, Maihafer GC, Walker R, Crouch JR, Van Lunen B, Morrison S. Virtual reality-enhanced partial body weight-supported treadmill training poststroke: feasibility and effectiveness in 6 subjects. OBJECTIVE To determine whether the use of a low-cost virtual reality (VR) system used in conjunction with partial body weight-supported treadmill training (BWSTT) was feasible and effective in improving the walking and balance abilities of patients poststroke. DESIGN A before-after comparison of a single group with BWSTT intervention. SETTING University research laboratory. PARTICIPANTS A convenience sample of 7 adults who were within 1 year poststroke and who had completed traditional rehabilitation but still exhibited gait deficits. Six participants completed the study. INTERVENTION Twelve treatment sessions of BWSTT with VR. The VR system generated a virtual environment that showed on a television screen in front of the treadmill to give participants the sensation of walking down a city street. A head-mounted position sensor provided postural feedback. MAIN OUTCOME MEASURES Functional Gait Assessment (FGA) score, Berg Balance Scale (BBS) score, and overground walking speed. RESULTS One subject dropped out of the study. All other participants made significant improvements in their ability to walk. FGA scores increased from mean of 13.8 to 18. BBS scores increased from mean of 43.8 to 48.8, although a ceiling effect was seen for this test. Overground walking speed increased from mean of .49m/s to .68m/s. CONCLUSIONS A low-cost VR system combined with BWSTT is feasible for improved gait and balance of patients poststroke.
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Lulé D, Ludolph AC, Kassubek J. MRI-based functional neuroimaging in ALS: an update. ACTA ACUST UNITED AC 2010; 10:258-68. [PMID: 19922112 DOI: 10.3109/17482960802353504] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
With non-invasive functional imaging techniques, neuroscience has reached a new era of connecting anatomy and function. Although other techniques bear the advantage of either higher temporal or spatial resolution, functional magnetic resonance imaging (fMRI) is the most widely used non-invasive brain imaging technique. fMRI provides an acceptable balance between low patient load and high information capacity with good spatial resolution, making it ideal for clinical research in patients with physical restrictions like those with ALS. Most fMRI studies have provided evidence of a spatial shift of function in motor and extramotor areas in ALS patients. Furthermore, MRI-based functional imaging has supported the clinical findings of frontal cortical involvement not only in patients with ALS/dementia complex but also in patients with ALS and sub-clinical cognitive impairment. Functional MRI will identify the preserved but non-executable functions in ALS patients in the end stage and will set the direction for a new way of thinking on the functional capacities of these patients which will have a major impact on our way of thinking about end-of-life decisions.
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Affiliation(s)
- Dorothée Lulé
- Section of Neurophysiology, Department of Neurology, University of Ulm, Albert-Einstein-Allee 47, Ulm, Germany.
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36
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Rosenbloom MJ, Sassoon SA, Pfefferbaum A, Sullivan EV. Contribution of Regional White Matter Integrity to Visuospatial Construction Accuracy, Organizational Strategy, and Memory for a Complex Figure in Abstinent Alcoholics. Brain Imaging Behav 2009; 3:379-390. [PMID: 20161607 PMCID: PMC2811340 DOI: 10.1007/s11682-009-9080-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Visuospatial construction ability as used in drawing complex figures is commonly impaired in chronic alcoholics, but memory for such information can be enhanced by use of a holistic drawing strategy during encoding. We administered the Rey-Osterrieth Complex Figure Test (ROCFT) to 41 alcoholic and 38 control men and women and assessed the contribution of diffusion tensor imaging (DTI) measures of integrity of selected white matter tracts to ROCFT copy accuracy, copy strategy, and recall accuracy. Although alcoholics copied the figure less accurately than controls, a more holistic strategy at copy was associated with better recall in both groups. Greater radial diffusivity, reflecting compromised myelin integrity, in occipital forceps and external capsule was associated with poorer copy accuracy in both groups. Lower FA, reflecting compromised fiber microstructure in the inferior cingulate bundle, which links frontal and medial temporal episodic memory systems, was associated with piecemeal copy strategy and poorer immediate recall in the alcoholics. The correlations were generally modest and should be considered exploratory. To the extent that the inferior cingulate was relatively spared in alcoholics, it may have provided an alternative pathway to the compromised frontal system for successful copy strategy and, by extension, aided recall.
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Affiliation(s)
- Margaret J. Rosenbloom
- Department of Psychiatry and Behavioral Sciences (MC 5723), Stanford University School of Medicine, 401 Quarry Road, Stanford, CA 94305-5723, USA
- Neuroscience Program, SRI International, Menlo Park, CA 94025, USA
| | | | | | - Edith V. Sullivan
- Department of Psychiatry and Behavioral Sciences (MC 5723), Stanford University School of Medicine, 401 Quarry Road, Stanford, CA 94305-5723, USA,
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Jacobs JV, Lou JS, Kraakevik JA, Horak FB. The supplementary motor area contributes to the timing of the anticipatory postural adjustment during step initiation in participants with and without Parkinson's disease. Neuroscience 2009; 164:877-85. [PMID: 19665521 PMCID: PMC2762010 DOI: 10.1016/j.neuroscience.2009.08.002] [Citation(s) in RCA: 165] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Revised: 07/17/2009] [Accepted: 08/03/2009] [Indexed: 11/22/2022]
Abstract
The supplementary motor area (SMA) is thought to contribute to the generation of anticipatory postural adjustments (APAs, which act to stabilize supporting body segments prior to movement), but its precise role remains unclear. In addition, participants with Parkinson's disease (PD) exhibit impaired function of the SMA as well as decreased amplitudes and altered timing of the APA during step initiation, but the contribution of the SMA to these impairments also remains unclear. To determine how the SMA contributes to generating the APA and to the impaired APAs of participants with PD, we examined the voluntary steps of eight participants with PD and eight participants without PD, before and after disrupting the SMA and dorsolateral premotor cortex (dlPMC), in separate sessions, with 1-Hz repetitive transcranial magnetic stimulation (rTMS). Both groups exhibited decreased durations of their APAs after rTMS over the SMA but not over the dlPMC. Peak amplitudes of the APAs were unaffected by rTMS to either site. The symptom severity of the participants with PD positively correlated with the extent that rTMS over the SMA affected the durations of their APAs. The results suggest that the SMA contributes to the timing of the APA and that participants with PD exhibit impaired timing of their APAs, in part, due to progressive dysfunction of circuits associated with the SMA.
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Affiliation(s)
- J V Jacobs
- Department of Rehabilitation and Movement Science, University of Vermont, Burlington, VT, USA.
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Yu J, Zeng J, Cheung RT, Xiong L, He M, Liang Z, Hong H, Huang R. INTRACEREBROVENTRICULAR INJECTION OF EPIDERMAL GROWTH FACTOR REDUCES NEUROLOGICAL DEFICIT AND INFARCT VOLUME AND ENHANCES NESTIN EXPRESSION FOLLOWING FOCAL CEREBRAL INFARCTION IN ADULT HYPERTENSIVE RATS. Clin Exp Pharmacol Physiol 2009; 36:539-46. [DOI: 10.1111/j.1440-1681.2008.05105.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Burridge JH, Turk R, Notley SV, Pickering RM, Simpson DM. The relationship between upper limb activity and impairment in post-stroke hemiplegia. Disabil Rehabil 2009; 31:109-17. [PMID: 18608395 DOI: 10.1080/09638280701824699] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
PURPOSE To investigate the relationship between upper limb impairments and activity limitation. METHOD A cross sectional, single assessment observational study in which people with hemiplegia as a result of a stroke underwent a testing procedure in an instrumented wrist rig in which the following measures of impairment were recorded: Spasticity; motor control (ability to track a moving target); muscle activation patterns during tracking; stiffness; range of active movement and isometric muscle strength. Participants also performed clinical tests of upper limb activity (Action Research Arm Test) and hyper-tonicity (Modified Ashworth Scale). RESULTS Seventeen people with hemiplegia whose mean age was 57 (SD 13.4) took part. Their mean upper limb activity, measured by the Action Research Arm Test, was 19.3 (SD 11.2). Statistically significant positive relationships between level of activity and the negative features of the upper motor neuron syndrome such as motor control r = 0.710 (p = 0.003), active range of movement r = 0.540 (p = 0.025) and strength into flexion r = 0.515 (p = 0.034) and extension r = 0.575 (p = 0.016) were identified, but not with the positive features, such as spasticity or the secondary features such as stiffness. CONCLUSIONS The negative features of the upper motor neuron syndrome appear more likely to affect upper limb activity than the positive or secondary features, but findings need confirming in different study populations, preferably with larger samples.
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Cauraugh JH, Coombes SA, Lodha N, Naik SK, Summers JJ. Upper extremity improvements in chronic stroke: coupled bilateral load training. Restor Neurol Neurosci 2009; 27:17-25. [PMID: 19164850 DOI: 10.3233/rnn-2009-0455] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND The current treatment intervention study determined the effect of coupled bilateral training (i.e., bilateral movements and EMG-triggered neuromuscular stimulation) and resistive load (mass) on upper extremity motor recovery in chronic stroke. METHODS Thirty chronic stroke subjects were randomly assigned to one of three behavioral treatment groups and completed 6 hours of rehabilitation in 4 days: (1) coupled bilateral training with a load on the unimpaired hand, (2) coupled bilateral training with no load on the unimpaired hand, and (3) control (no stimulation assistance or load). RESULTS Separate mixed design ANOVAs revealed improved motor capabilities by the coupled bilateral groups. From the pretest to the posttest, both the coupled bilateral no load and load groups moved a higher number of blocks and demonstrated more regularity in the sustained contraction task. Faster motor reaction times across test sessions for the coupled bilateral load group provided additional evidence for improved motor capabilities. CONCLUSIONS Together these behavioral findings lend support to the contribution of coupled bilateral training with a load on the unimpaired arm to improved motor capabilities on the impaired arm. This evidence supports a neural explanation in that simultaneously moving both limbs during stroke rehabilitation training appears to activate balanced interhemispheric interactions while an extra load on the unimpaired limb provides stability to the system.
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Affiliation(s)
- James H Cauraugh
- Motor Behavior Laboratory, Applied Physiology and Kinesiology Department, University of Florida, Gainesville, FL 32611, USA.
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Qureshi AI, Suri MFK, Georgiadis AL, Vazquez G, Janjua NA. Intra-arterial recanalization techniques for patients 80 years or older with acute ischemic stroke: pooled analysis from 4 prospective studies. AJNR Am J Neuroradiol 2009; 30:1184-9. [PMID: 19342542 DOI: 10.3174/ajnr.a1503] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Previous studies have demonstrated limited benefit with endovascular procedures such as stent placement in octogenarians. We evaluated the safety and effectiveness of intra-arterial recanalization techniques to treat ischemic stroke in patients 80 years or older presenting within 6 hours of symptom onset. MATERIALS AND METHODS We pooled the data from 4 prospective studies by evaluating intra-arterial recanalization techniques for treatment of ischemic stroke. Clinical and radiologic evaluations were performed before treatment and at 24 hours, 7 to 10 days, and 1 to 3 months after treatment. We performed multivariate analyses to evaluate the effect of ages 80 years and older on angiographic recanalization, favorable outcome (modified Rankin scale of 0-2), and mortality rate at 1 to 3 months. RESULTS A total of 101 patients were treated in the 4 protocols. Of these, 24 were 80 years or older. There was no significant difference between the 2 age groups in sex, initial stroke severity, time to treatment, site of vascular occlusion, and rate of symptomatic and asymptomatic intracranial hemorrhage (ICH). In logistic regression analysis, age 80 years or older was associated with a lower likelihood of a favorable outcome (odds ratio [OR], 0.40; 95% confidence interval [CI], 0.13-1.2; P = .11) and recanalization (OR, 0.36; 95% CI, 0.12-1.1; P = .07) and with higher mortality rate (OR, 3.17; 95% CI, 1.05-9.55; P = .04) after adjusting for study protocol. After adjusting for recanalization in addition to study protocol, the older age group still had a lower likelihood of favorable outcomes (OR, 0.34; 95% CI, 0.1-1.1; P = .07) and higher mortality rates (OR, 3.62; 95% CI, 1.15-11.36; P = .027). CONCLUSIONS Our study demonstrates that patients 80 years and older are at higher risk for poor outcome at 1 to 3 months following intra-arterial recanalization techniques. This relationship is independent of recanalization rate and symptomatic ICH supporting the role of other mechanisms.
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Affiliation(s)
- A I Qureshi
- Zeenat Qureshi Stroke Research Center, Department of Neurology, University of Minnesota, Minneapolis, MN 55455, USA.
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Cheeran B, Cohen L, Dobkin B, Ford G, Greenwood R, Howard D, Husain M, Macleod M, Nudo R, Rothwell J, Rudd A, Teo J, Ward N, Wolf S. The future of restorative neurosciences in stroke: driving the translational research pipeline from basic science to rehabilitation of people after stroke. Neurorehabil Neural Repair 2009; 23:97-107. [PMID: 19189939 PMCID: PMC3230220 DOI: 10.1177/1545968308326636] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Major advances during the past 50 years highlight the immense potential for restoration of function after neural injury, even in the damaged adult human brain. Yet, the translation of these advances into clinically useful treatments is painstakingly slow. OBJECTIVE Here, we consider why the traditional model of a "translational research pipeline" that transforms basic science into novel clinical practice has failed to improve rehabilitation practice for people after stroke. RESULTS We find that (1) most treatments trialed in vitro and in animal models have not yet resulted in obviously useful functional gains in patients; (2) most clinical trials of restorative treatments after stroke have been limited to small-scale studies; (3) patient recruitment for larger clinical trials is difficult; (4) the determinants of patient outcomes and what patients want remain complex and ill-defined, so that basic scientists have no clear view of the clinical importance of the problems that they are addressing; (5) research in academic neuroscience centers is poorly integrated with practice in front-line hospitals and the community, where the majority of patients are treated; and (6) partnership with both industry stakeholders and patient pressure groups is poorly developed, at least in the United Kingdom where research in the translational restorative neurosciences in stroke depends on public sector research funds and private charities. CONCLUSIONS We argue that interaction between patients, front-line clinicians, and clinical and basic scientists is essential so that they can explore their different priorities, skills, and concerns. These interactions can be facilitated by funding research consortia that include basic and clinical scientists, clinicians and patient/carer representatives with funds targeted at those impairments that are major determinants of patient and carer outcomes. Consortia would be instrumental in developing a lexicon of common methods, standardized outcome measures, data sharing and long-term goals. Interactions of this sort would create a research-friendly, rather than only target-led, culture in front-line stroke rehabilitation services.
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Abstract
Recovery of function after damage to the CNS is limited due to the absence of axon regeneration and relatively low levels of plasticity. Plasticity in the CNS can be reactivated in the adult CNS by treatment with chondroitinase ABC, which removes glycosaminoglycan (GAG) chains from chondroitin sulfate proteoglycans (CSPGs). Plasticity in the adult CNS is restricted by perineuronal nets (PNNs) around many neuronal cell bodies and dendrites, which appear at the closure of critical periods and contain several inhibitory CSPGs. Formation of these structures and the turning off of plasticity is triggered by impulse activity in neurons. Expression of a link protein by neurons is the event that triggers the formation of PNNs. Treatment with chondroitinase removes PNNs and other inhibitory influences in the damaged spinal cord and promotes sprouting of new connections. However, promoting plasticity by itself does not necessarily bring back useful behavior; this only happens when useful connections are stabilized and inappropriate connections removed, driven by behavior. Thus after rodent spinal cord injury, combining a daily rehabilitation treatment for skilled paw function with chondroitinase produces much greater recovery than either treatment alone. The rehabilitation must be specific for the behavior that is to be enhanced because non-specific rehabilitation improves locomotor behavior but not skilled paw function. Plasticity-enhancing treatments may therefore open up a window of opportunity for successful rehabilitation.
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Affiliation(s)
- James Fawcett
- Cambridge University Centre for Brain Repair, Department of Clinical Neurosciences, Cambridge, UK.
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44
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Hummel FC, Celnik P, Pascual-Leone A, Fregni F, Byblow WD, Buetefisch CM, Rothwell J, Cohen LG, Gerloff C. Controversy: Noninvasive and invasive cortical stimulation show efficacy in treating stroke patients. Brain Stimul 2008; 1:370-82. [DOI: 10.1016/j.brs.2008.09.003] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2008] [Revised: 09/03/2008] [Accepted: 09/05/2008] [Indexed: 11/17/2022] Open
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Galtrey CM, Kwok JCF, Carulli D, Rhodes KE, Fawcett JW. Distribution and synthesis of extracellular matrix proteoglycans, hyaluronan, link proteins and tenascin-R in the rat spinal cord. Eur J Neurosci 2008; 27:1373-90. [PMID: 18364019 DOI: 10.1111/j.1460-9568.2008.06108.x] [Citation(s) in RCA: 150] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Perineuronal nets (PNNs) are dense extracellular matrix (ECM) structures that form around many neuronal cell bodies and dendrites late in development. They contain several chondroitin sulphate proteoglycans (CSPGs), hyaluronan, link proteins and tenascin-R. Their time of appearance correlates with the ending of the critical period for plasticity, and they have been implicated in this process. The distribution of PNNs in the spinal cord was examined using Wisteria floribunda agglutinin lectin and staining for chondroitin sulphate stubs after chondroitinase digestion. Double labelling with the neuronal marker, NeuN, showed that PNNs were present surrounding approximately 30% of motoneurons in the ventral horn, 50% of large interneurons in the intermediate grey and 20% of neurons in the dorsal horn. These PNNs formed in the second week of postnatal development. Immunohistochemical staining demonstrated that the PNNs contain a mixture of CSPGs, hyaluronan, link proteins and tenascin-R. Of the CSPGs, aggrecan was present in all PNNs while neurocan, versican and phosphacan/RPTPbeta were present in some but not all PNNs. In situ hybridization showed that aggrecan and cartilage link protein (CRTL 1) and brain link protein-2 (BRAL 2) are produced by neurons. PNN-bearing neurons express hyaluronan synthase, and this enzyme and phosphacan/RPTPbeta may attach PNNs to the cell surface. During postnatal development the expression of link protein and aggrecan mRNA is up-regulated at the time of PNN formation, and these molecules may therefore trigger their formation.
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Affiliation(s)
- Clare M Galtrey
- Cambridge Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Robinson Way, Cambridge, CB2 2PY, UK
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Ziemann U, Siebner HR. Modifying motor learning through gating and homeostatic metaplasticity. Brain Stimul 2007; 1:60-6. [PMID: 20633369 DOI: 10.1016/j.brs.2007.08.003] [Citation(s) in RCA: 184] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Revised: 08/22/2007] [Accepted: 08/22/2007] [Indexed: 12/31/2022] Open
Abstract
Synaptic plasticity in the motor cortex is involved at least in some forms of motor learning. Recent evidence showed that the extent of practice-dependent plasticity in the motor cortex can be purposefully enhanced by experimental manipulation. One way of improving motor learning is to transiently increase the excitability of the motor cortex during motor learning. This can be achieved by weakening the excitability of intracortical inhibitory circuits concurrently with practice. This principle is being referred to as "gating." Another strategy to boost learning is to decrease the threshold for induction of synaptic plasticity by lowering neuronal activity in the motor cortex before practice. This approach invokes homeostatic metaplasticity. Here we highlight how transcranial brain stimulation can exploit gating and homeostatic metaplasticity to enhance motor learning in healthy subjects and in patients after stroke.
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Affiliation(s)
- Ulf Ziemann
- Department of Neurology, Johann Wolfgang Goethe-University, Frankfurt am Main, Germany.
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Moller HJ, Mikulis DJ. Neurocognitive disability, stroke, and surgery: a role for neuroergonomics? J Psychosom Res 2007; 63:613-5. [PMID: 18061751 DOI: 10.1016/j.jpsychores.2007.06.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2007] [Indexed: 11/28/2022]
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Tuor UI, Wang R, Zhao Z, Foniok T, Rushforth D, Wamsteeker JI, Qiao M. Transient hypertension concurrent with forepaw stimulation enhances functional MRI responsiveness in infarct and peri-infarct regions. J Cereb Blood Flow Metab 2007; 27:1819-29. [PMID: 17377516 DOI: 10.1038/sj.jcbfm.9600472] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Although functional magnetic resonance imaging (fMRI) is gaining use as a tool to assess cerebral recovery following various insults, the effects of potential confounders such as hypertension are poorly defined. We hypothesized that after stroke, transient hypertension during an fMRI study could produce a detected activation unrelated to neuronal activity within the infarct. Thus, the effect of norepinephrine induced increases in blood pressure (BP) on the fMRI response to forepaw stimulation were investigated in controls or 1 week after transient middle cerebral artery occlusion in rats. Images were smoothed spatially and voxels correlating to either forepaw stimulation or the change in BP time courses were analyzed. Transient hypertension increased the signal intensity and numbers of voxels correlating to the BP time courses within and adjacent to the ischemic infarct and these exceeded the response in the contralateral hemisphere or in controls. With left paw stimulation at normotension, there was a loss of activation in right sensory-motor cortex -- a region with necrosis and disruption of cerebral vessels. As BP increased left paw stimulation also resulted in the detection of activation in the infarcted sensory-motor cortex and peri-infarct regions. Thus, BP changes synchronous with tasks in fMRI studies can result in MR signal changes consistent with a loss of cerebral blood flow (CBF) autoregulation rather than neuronal activation in necrotic brain. After stroke, the use of stressful tasks associated with BP changes in fMRI studies should be limited or the BP change should be considered as a potential source of MR signal changes.
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Affiliation(s)
- Ursula I Tuor
- MR Technology, Institute for Biodiagnostics (West), National Research Council, Calgary, Alberta, Canada.
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Rodríguez-González R, Hurtado O, Sobrino T, Castillo J. Neuroplasticity and cellular therapy in cerebral infarction. Cerebrovasc Dis 2007; 24 Suppl 1:167-80. [PMID: 17971653 DOI: 10.1159/000107393] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Stroke is the second to third most common cause of death in adults, and more than a third of people who survive a stroke will have severe disability. Therapeutic options currently centre on fibrinolytic treatment, but its limitations restrict use to a small proportion of patients. Although a wide range of neuroprotective substances has been effective in experimental models, they have repeatedly failed in clinical trials because of toxicity or loss of effectiveness. Recent strategies based on neuroplasticity and cellular therapy have shown significant efficacy in improving functional recovery in experimental models, although further study is still necessary to clarify how the brain responds to ischaemic damage and is able to reorganize itself in the long term. Although steps must still be taken to ensure the safety and feasibility of treatments based on neuroplasticity and cellular therapy, neurorepair strategies provide promising future therapeutic options for stroke.
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Affiliation(s)
- Raquel Rodríguez-González
- Clinical Neuroscience Research Laboratory, Division of Vascular Neurology, Department of Neurology, Hospital Clínico Universitario, University of Santiago de Compostela, Santiago de Compostela, Spain
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Ramirez JJ, Campbell D, Poulton W, Barton C, Swails J, Geghman K, Courchesne SL, Wentworth S. Bilateral entorhinal cortex lesions impair acquisition of delayed spatial alternation in rats. Neurobiol Learn Mem 2007; 87:264-8. [PMID: 17049284 PMCID: PMC1839929 DOI: 10.1016/j.nlm.2006.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2006] [Revised: 09/03/2006] [Accepted: 09/06/2006] [Indexed: 01/18/2023]
Abstract
Entorhinal cortex lesions induce significant reorganization of several homotypic and heterotypic inputs to the hippocampus. This investigation determined whether surviving heterotypic inputs after bilateral entorhinal lesions would support the acquisition of a learned alternation task. Rats with entorhinal lesions or sham operations were trained to acquire a spatial alternation task. Although the sham-operated rats acquired the task within about 3 weeks postsurgery, rats with bilateral entorhinal lesions failed to learn the task after 12 consecutive weeks of training despite heterotypic sprouting of the cholinergic septodentate pathway and the expansion of the commissural/associational fiber plexus within the dentate gyrus. Thus, heterotypic sprouting failed to ameliorate significantly the effects of bilateral entorhinal lesions. Rather, entorhinal lesions produced a persistent impairment of spatial memory, characterized by a mixture of random error production and perseverative responding.
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Affiliation(s)
- Julio J Ramirez
- Department of Psychology and Neuroscience Program, Davidson College, Davidson, NC 28035, USA.
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