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Wåhlin, A., Fordell, H., Ekman, U., Lenfeldt, N. & Malm, J. (2019). Rehabilitation in chronic spatial neglect strengthens resting-state connectivity. Acta Neurologica Scandinavica, 139(3), 254-259
Open this publication in new window or tab >>Rehabilitation in chronic spatial neglect strengthens resting-state connectivity
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2019 (English)In: Acta Neurologica Scandinavica, ISSN 0001-6314, E-ISSN 1600-0404, Vol. 139, no 3, p. 254-259Article in journal (Refereed) Published
Abstract [en]

Objectives: Rehabilitation of patients with chronic visuospatial neglect is underexplored, and little is known about neural mechanisms that can be exploited to promote recovery. In this study, we present data on resting-state functional connectivity within the dorsal attention network (DAN) in chronic neglect patients as they underwent training in a virtual reality (VR) environment that improved left-side awareness.

Methods: The study included 13 patients with visuospatial neglect persisting more than six months after a right-sided stroke. The patients underwent resting-state functional magnetic resonance imaging (fMRI). Scans were collected at baseline and after five weeks of intense training. We specifically examined resting-state functional connectivity within the DAN. In addition, using spatial concordance correlation, we compared changes in the spatial topology of the DAN with that of other networks.

Results: We found a longitudinal increase in interhemispheric functional connectivity between the right frontal eye field and the left intraparietal sulcus following training (before: 0.33 +/- 0.17 [mean +/- SD]; after: 0.45 +/- 0.13; P = 0.004). The spatial concordance analyses indicated that training influenced the DAN connectivity more than any of the other networks.

Conclusion: Intense VR training that improved left-sided awareness in chronic stroke patients also increased sporadic interhemispheric functional connectivity within the DAN. Specifically, a region responsible for saccadic eye movement to the left became more integrated with the left posterior parietal cortex. These results highlight a mechanism that should be exploited in the training of patients with chronic visuospatial neglect.

Place, publisher, year, edition, pages
John Wiley & Sons, 2019
Keywords
cognitive rehabilitation, functional magnetic resonance imaging, neuronal plasticity, spatial neglect, virtual reality
National Category
Neurology
Identifiers
urn:nbn:se:umu:diva-156864 (URN)10.1111/ane.13048 (DOI)000458682700006 ()30427058 (PubMedID)
Available from: 2019-03-13 Created: 2019-03-13 Last updated: 2019-03-13Bibliographically approved
Ekman, U., Fordell, H., Eriksson, J., Lenfeldt, N., Wåhlin, A., Eklund, A. & Malm, J. (2018). Increase of frontal neuronal activity in chronic neglect after training in virtual reality. Acta Neurologica Scandinavica, 138(4), 284-292
Open this publication in new window or tab >>Increase of frontal neuronal activity in chronic neglect after training in virtual reality
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2018 (English)In: Acta Neurologica Scandinavica, ISSN 0001-6314, E-ISSN 1600-0404, Vol. 138, no 4, p. 284-292Article in journal (Refereed) Published
Abstract [en]

Objectives: A third of patients with stroke acquire spatial neglect associated with poor rehabilitation outcome. New effective rehabilitation interventions are needed. Scanning training combined with multisensory stimulation to enhance the rehabilitation effect is suggested. In accordance, we have designed a virtual-reality based scanning training that combines visual, audio and sensori-motor stimulation called RehAtt((R)). Effects were shown in behavioural tests and activity of daily living. Here, we use fMRI to evaluate the change in brain activity during Posners Cuing Task (attention task) after RehAtt((R)) intervention, in patients with chronic neglect.

Methods: Twelve patients (mean age=72.7years, SD=6.1) with chronic neglect (persistent symptoms >6months) performed the interventions 3 times/wk during 5weeks, in total 15hours. Training effects on brain activity were evaluated using fMRI task-evoked responses during the Posners cuing task before and after the intervention.

Results: Patients improved their performance in the Posner fMRI task. In addition, patients increased their task-evoked brain activity after the VR interventions in an extended network including pre-frontal and temporal cortex during attentional cueing, but showed no training effects during target presentations.

Conclusions: The current pilot study demonstrates that a novel multisensory VR intervention has the potential to benefit patients with chronic neglect in respect of behaviour and brain changes. Specifically, the fMRI results show that strategic processes (top-down control during attentional cuing) were enhanced by the intervention. The findings increase knowledge of the plasticity processes underlying positive rehabilitation effects from RehAtt((R)) in chronic neglect.

Place, publisher, year, edition, pages
John Wiley & Sons, 2018
Keywords
cognitive rehabilitation, functional magnetic resonance imaging, neuronal plasticity, spatial neglect, virtual reality
National Category
Neurology
Identifiers
urn:nbn:se:umu:diva-152199 (URN)10.1111/ane.12955 (DOI)000443931400003 ()29770439 (PubMedID)
Available from: 2018-10-31 Created: 2018-10-31 Last updated: 2019-05-07Bibliographically approved
Fordell, H., Wåhlin, A., Ekman, U., Lenfeldt, N. & Malm, J. (2018). Rehabilitation in chronic neglect using VR strengthens connectivity between nodes of the dorsal attention network. International Journal of Stroke, 13, 50-50
Open this publication in new window or tab >>Rehabilitation in chronic neglect using VR strengthens connectivity between nodes of the dorsal attention network
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2018 (English)In: International Journal of Stroke, ISSN 1747-4930, E-ISSN 1747-4949, Vol. 13, p. 50-50Article in journal, Meeting abstract (Other academic) Published
Abstract [en]

More knowledge is required about the neural mechanisms of functional recovery of spatial neglect in chronic phase after stroke. In this functional magnetic resonance imaging (fMRI) study, we aimed to evaluate changes in resting state functional connectivity (FC) within the dorsal attention network (DAN) in chronic neglect after scanning training in VR that previously shown improvement in left side awareness in behavioral tests and activity of daily living. (Fordell et al 2016)

Method: Thirteen subjects with chronic spatial neglect (mean duration ¼ 43 months, SD ¼ 29 months) underwent resting state fMRI at baseline and after 15 hours RehAtt training (3x1hr / week for 5 weeks). RehAtt scanning training in 3D includes multi-sensory stimulation and is controlled by their contra-lesional hand using a robotic pen (force-feedback). The analysis specifically examined resting state functional connectivity within the DAN. In addition, using spatial concordance correlation, changes in the spatial topology of the DAN to other networks were analyzed.

Results: We found an increase in interhemispheric FC between the right FEF and the left IPS following training (pre: 0.33 0.17 [mean SD]; post: 0.45 0.13; p ¼ 0.004). The spatial concordance analyses indicated that training had stronger influence on the DAN compared to other networks.

Conclusion: VR training that improved left side awareness in chronic stroke patients also increased connectivity within the DAN. Specifically, a region responsible for saccadic eye movement to the left became more integrated with the left posterior parietal cortex. These results highlight a mechanism that can be exploited in the rehabilitation of chronic spatial neglect

Place, publisher, year, edition, pages
Sage Publications, 2018
National Category
Neurology
Identifiers
urn:nbn:se:umu:diva-153664 (URN)000448113300195 ()
Available from: 2018-11-26 Created: 2018-11-26 Last updated: 2018-11-26Bibliographically approved
Fordell, H., Wahlin, A., Ekman, U., Lenfeldt, N. & Malm, J. (2018). Rehabilitation of chronic spatial neglect strengthens functional connectivity between nodes of the dorsal attention network. International Journal of Stroke, 13, 42-42
Open this publication in new window or tab >>Rehabilitation of chronic spatial neglect strengthens functional connectivity between nodes of the dorsal attention network
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2018 (English)In: International Journal of Stroke, ISSN 1747-4930, E-ISSN 1747-4949, Vol. 13, p. 42-42Article in journal, Meeting abstract (Other academic) Published
Place, publisher, year, edition, pages
Sage Publications, 2018
National Category
Neurology
Identifiers
urn:nbn:se:umu:diva-154840 (URN)000452504600182 ()
Note

Supplement: 3Special Issue: SIMeeting Abstract: 154

Available from: 2019-02-28 Created: 2019-02-28 Last updated: 2019-02-28Bibliographically approved
Fordell, H. (2017). Virtual Reality for Enriched Rehabilitation of Stroke Patients with Spatial Neglect: Diagnostics and the Rehabilitation Effect on Spatial Attention and Neuronal Activity. (Doctoral dissertation). Umeå universitet
Open this publication in new window or tab >>Virtual Reality for Enriched Rehabilitation of Stroke Patients with Spatial Neglect: Diagnostics and the Rehabilitation Effect on Spatial Attention and Neuronal Activity
2017 (English)Doctoral thesis, comprehensive summary (Other academic)
Alternative title[sv]
Virtual reality-förstärkt rehabilitering för strokepatienter med spatialt neglekt : diagnostik och utvärdering av rehabiliteringseffekt på spatial uppmärksamhet och neuronal aktivitet
Abstract [en]

Background: Approximately a third of all stroke patients develop spatial neglect, a debilitating symptom associated with poor outcome. Spatial neglect is clinically defined as a deficit in processing and responding to stimuli presented on the contralesional side of the body, or the space surrounding that side of the body. The heterogenetic, multi-sensory nature of the symptoms renders it difficult to diagnose and treat; therefor effective methods for screening and intervention for neglect are needed. Virtual reality (VR) is a method of brain–computer interaction that involves realtime simulation of an environment, scenario or activity that allows for user interaction and targets multiple senses. We hypothesize that VR can facilitate identification of spatial neglect in stroke patients and that training with this interface will improve patient’s functional outcome, through stimulation to neuronal networks including those controlling attention.

Objective: The objective was to construct and validate a computerized test battery for spatial neglect and to investigate its usability in stroke patients. Also to design and develop a VR rehabilitation method for spatial neglect and to evaluate its effects on spatial attention and on neuronal activity in the brain.

Method: We designed, developed and evaluated a new concept for assessment (VR-DiSTRO®) and training (RehAtt®) of spatial attention, using VR technology. The hardware consisted of a PC, monitor, 3D-glasses and a force feedback device to control the tasks (i.e., a robotic pen). The software enabled targets to be moved, rotated and manipulated in the 3D environment using the robotic pen. RehAtt® made it possible to combine intense visual scanning training, multi-sensory stimulation (i.e., audio, visual, tactile) and sensory-motor activation of the contralesional arm. In a first study on 31 stroke patients we performed a construct validation of VR-DiSTRO® against Rivermead Behavioural Test Battery (BIT) and investigated the usability. In a second study, 15 subjects with chronic spatial neglect (symptoms >6 month) had self-training, 3 x 1 hour for 5 weeks using RehAtt®. Outcome were measured by changes in neglect tests and in Cathrine Bergego Scale (CBS). Training-related changes in neuronal activity of the brain was studied using fMRI during task and in resting state.

Results: VR-DiSTRO® correctly identified all patients with neglect. The sensitivity was 100% and the specificity 82% for VR-DiSTRO® compared to BIT. Usability was high and no side-effects were noted. Using repeated measurement analysis, improvements due to the RehAtt® intervention were found for Baking tray task (p < 0.001), Star cancellation test (p = 0.006) and Extinction test (p = 0.05). Improvements were also seen in the Posner task as fewer missed targets (p = 0.024). Improvement in activities of daily living (CBS) was shown immediately after training (p < 0.01) and patients still reported improvement at 6 months follow-up. Trainingrelated changes in neuronal activity were seen as an increased task-evoked brain activity in prefrontal and temporal cortex, mainly outside the attention network but in related cortical areas. During resting state, changes in network connectivity were seen after intervention with RehAtt® in the Dorsal Attention Network (DAN) and interhemispheric connectivity.

Conclusion: VR-DiSTRO® identified visuospatial neglect in stroke patients quickly and with a high accuracy. RehAtt® training improved in spatial attention in chronic neglect with transfer to functions in daily living. Increased neuronal brain activity was found in and between attention networks and related brain structures. This could represent a compensatory effect in addition to sign of a restorative effect from the RehAtt training. The results obtained in this study are promising, encourage further development of the methods and merit for further studies.

Place, publisher, year, edition, pages
Umeå universitet, 2017. p. 77
Series
Umeå University medical dissertations, ISSN 0346-6612 ; 1929
Keywords
Stroke, spatial neglect, rehabilitation, virtual reality, enriched environment, fMRI
National Category
Neurology
Identifiers
urn:nbn:se:umu:diva-141920 (URN)978-91-7601-792-0 (ISBN)
Public defence
2017-12-08, Sal E04, R1, Norrlands Universitetssjukhus, Umeå, 09:00 (English)
Opponent
Supervisors
Funder
Västerbotten County CouncilEU, FP7, Seventh Framework Programme
Available from: 2017-11-16 Created: 2017-11-15 Last updated: 2018-06-09Bibliographically approved
Fordell, H., Bodin, K., Eklund, A. & Malm, J. (2016). RehAtt – scanning training for neglect enhanced by multi-sensory stimulation in Virtual Reality. Topics in Stroke Rehabilitation, 23(3), 191-199
Open this publication in new window or tab >>RehAtt – scanning training for neglect enhanced by multi-sensory stimulation in Virtual Reality
2016 (English)In: Topics in Stroke Rehabilitation, ISSN 1074-9357, E-ISSN 1945-5119, Vol. 23, no 3, p. 191-199Article in journal (Refereed) Published
Abstract [en]

Background: There is a lack of effective treatment for neglect. We have developed a new training method, RehAtt (TM). The objective of this study was to determine whether RehAtt (TM) improves spatial attention in chronic neglect after stroke. Methods: RehAtt (TM) consists of a computer with monitor, 3D glasses, and a force feedback interface (Robotic pen) giving sensory motor activation to the contra-lesional arm. The software combines visual scanning training with multi-sensory stimulation in 3D virtual reality (VR) game environment. Fifteen stroke patients with chronic neglect (duration > 6 month) had repeated baseline evaluations to confirm stability of symptoms. There were no test-retest effects for any of the tests. Thereafter, all patients trained 15 h in RehAtt (TM) (3 x 1 h for 5 weeks). A neglect test battery and Catherine Bergego Scale, CBS, were used to assess behavioral outcome after intervention. CBS was also used at a 6-month follow-up. Results: Using repeated measurement analysis improvements due to the training were found for Star cancellation test (p = 0.006), Baking tray task (p < 0.001), and Extinction test (p = 0.05). In the Posner task improvements were seen fewer missed targets (p = 0.024). CBS showed improvements in activities of daily life immediately after training (p < 0.01). After 6 months the patients still reported improvement in CBS. Conclusion: RehAtt (TM) is a new concept for rehabilitation of neglect. Training with the VR-method improved spatial attention and showed transfer to improved spatial attention in activities of daily living in chronic neglect. Our results are promising and merit further studies.

Place, publisher, year, edition, pages
Taylor & Francis Group, 2016
Keywords
Spatial neglect, Cognitive rehabilitation, Attention, treatment, virtual reality, stroke
National Category
Neurology
Identifiers
urn:nbn:se:umu:diva-121621 (URN)10.1080/10749357.2016.1138670 (DOI)000375149700007 ()27077985 (PubMedID)
Available from: 2016-06-20 Created: 2016-06-03 Last updated: 2018-06-07Bibliographically approved
Fordell, H., Bodin, K., Bucht, G. & Malm, J. (2011). A virtual reality test battery for assessment and screening of spatial neglect. Acta Neurologica Scandinavica, 123(3), 167-174
Open this publication in new window or tab >>A virtual reality test battery for assessment and screening of spatial neglect
2011 (English)In: Acta Neurologica Scandinavica, ISSN 0001-6314, E-ISSN 1600-0404, Vol. 123, no 3, p. 167-174Article in journal (Refereed) Published
Abstract [en]

Background – There is a need for improved screening methods for spatial neglect.

Aim – To construct a VR-test battery and evaluate its accuracy and usability in patients with acute stroke.

Method –  VR-DiSTRO consists of a standard desktop computer, a CRT monitor and eye shutter stereoscopic glasses, a force feedback interface, and software, developed to create an interactive and immersive 3D experience. VR-tests were developed and validated to the conventional Star Cancellation test, Line bisection, Baking Tray Task (BTT), and Visual Extinction test. A construct validation to The Rivermead Behavioral Inattention Test, used as criterion of visuospatial neglect, was made. Usability was assessed according to ISO 9241-11.

Results –  Thirty-one patients with stroke were included, 9/31 patients had neglect. The sensitivity was 100% and the specificity 82% for the VR-DiSTRO to correctly identify neglect. VR-BTT and VR-Extinction had the highest correlation (r2 = 0.64 and 0.78), as well as high sensitivity and specificity. The kappa values describing the agreement between traditional neglect tests and the corresponding virtual reality test were between 0.47–0.85. Usability was assessed by a questionnaire; 77% reported that the VR-DiSTRO was ‘easy’ to use. Eighty-eight percent reported that they felt ‘focused’, ‘pleased’ or ‘alert’. No patient had adverse symptoms. The test session took 15 min.

Conclusions –  The VR-DiSTRO quickly and with a high accuracy identified visuospatial neglect in patients with stroke in this construct validation. The usability among elderly patients with stroke was high. This VR-test battery has the potential to become an important screening instrument for neglect and a valuable adjunct to the neuropsychological assessment.

Place, publisher, year, edition, pages
John Wiley & Sons, 2011
Keywords
perceptual disorder, hemispatial neglect, diagnosis, neuro psychological tests, task performance and analysis, visual perception, user computer interface, stroke complications, assessment
National Category
Neurology Other Medical Sciences not elsewhere specified
Identifiers
urn:nbn:se:umu:diva-51122 (URN)10.1111/j.1600-0404.2010.01390.x (DOI)000286667900003 ()20569225 (PubMedID)
Available from: 2012-01-11 Created: 2012-01-11 Last updated: 2018-06-08Bibliographically approved
Ekman, U., Fordell, H., Eriksson, J., Lenfeldt, N., Wåhlin, A., Eklund, A. & Malm, J.Increase of frontal neuronal activity in chronic neglect after multi-sensory scanning training in virtual.
Open this publication in new window or tab >>Increase of frontal neuronal activity in chronic neglect after multi-sensory scanning training in virtual
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(English)Manuscript (preprint) (Other academic)
National Category
Neurology
Identifiers
urn:nbn:se:umu:diva-141923 (URN)
Available from: 2017-11-15 Created: 2017-11-15 Last updated: 2018-06-09
Wåhlin, A., Fordell, H., Ekman, U., Lenfeldt, N. & Malm, J.Rehabilitation of chronic spatial neglect strengthens functional connectivity between nodes of the dorsal attention network.
Open this publication in new window or tab >>Rehabilitation of chronic spatial neglect strengthens functional connectivity between nodes of the dorsal attention network
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(English)Manuscript (preprint) (Other academic)
National Category
Neurology
Identifiers
urn:nbn:se:umu:diva-141924 (URN)
Available from: 2017-11-15 Created: 2017-11-15 Last updated: 2018-06-09
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-1650-8856

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