The Experts below are selected from a list of 162 Experts worldwide ranked by ideXlab platform
Xaver Fuchs - One of the best experts on this subject based on the ideXlab platform.
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assessment of cortical reorganization and preserved function in phantom limb pain a methodological perspective
Scientific Reports, 2020Co-Authors: Jamila Andoh, Martin Diers, Xaver Fuchs, Christopher Milde, Jorg Trojan, Robin BekraterbodmannAbstract:Phantom limb pain (PLP) has been associated with reorganization in primary somatosensory cortex (S1) and preserved S1 function. Here we examined if methodological differences in the assessment of cortical representations might explain these findings. We used functional magnetic resonance imaging during a virtual reality movement task, analogous to the classical Mirror Box task, in twenty amputees with and without PLP and twenty matched healthy controls. We assessed the relationship between task-related activation maxima and PLP intensity in S1 and motor cortex (M1) in individually-defined or group-conjoint regions of interest (ROI) (overlap of task-related activation between the groups). We also measured cortical distances between both locations and correlated them with PLP intensity. Amputees compared to controls showed significantly increased activation in M1, S1 and S1M1 unrelated to PLP. Neural activity in M1 was positively related to PLP intensity in amputees with PLP when a group-conjoint ROI was chosen. The location of activation maxima differed between groups in S1 and M1. Cortical distance measures were unrelated to PLP. These findings suggest that sensory and motor maps differentially relate to PLP and that methodological differences might explain discrepant findings in the literature.
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assessment of cortical reorganization and preserved function in phantom limb pain a methodological perspective
arXiv: Neurons and Cognition, 2019Co-Authors: Jamila Andoh, Martin Diers, Xaver Fuchs, Christopher Milde, Jorg Trojan, Robin BekraterbodmannAbstract:Phantom limb pain (PLP) has been associated with both the reorganization of the somatotopic map in primary somatosensory cortex (S1) and preserved S1 function. Here we assessed the nature of the information (sensory, motor) that reaches S1 and methodological differences in the assessment of cortical representations that might explain these findings. We used functional magnetic resonance imaging during a virtual hand motor task, analogous to the classical Mirror Box task, in amputees with and without PLP and in matched controls. We assessed the relationship between task-related activation maxima and PLP intensity in S1 versus motor (M1) maps. We also measured cortical distances between the location of activation maxima using region of interest (ROI), defined from individual or group analyses. Amputees showed significantly increased activity in M1 and S1 compared to controls, which was not significantly related to PLP intensity. The location of activation maxima differed between groups depending on M1 and S1 maps. Neural activity was positively related to PLP only in amputees with pain and only if a group-defined ROI was chosen. These findings show that the analysis of changes in S1 versus M1 yields different results, possibly indicating different pain-related processes.
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do Mirror glasses have the same effect on brain activity as a Mirror Box evidence from a functional magnetic resonance imaging study with healthy subjects
PLOS ONE, 2015Co-Authors: Christopher Milde, Pinar Kirsch, Jens Foell, Xaver Fuchs, Mariela Rance, Jorg Trojan, Robin Bekraterbodmann, Herta Flor, Martin DiersAbstract:Since its original proposal, Mirror therapy has been established as a successful neurorehabilitative intervention in several neurological disorders to recover motor function or to relieve pain. Mirror therapy seems to operate by reactivating the contralesional representation of the non-Mirrored limb in primary motor- and somatosensory cortex. However, Mirror Boxes have some limitations which prompted the use of additional Mirror visual feedback devices. The present study evaluated the utility of Mirror glasses compared to a Mirror Box. We also tested the hypothesis that increased interhemispheric communication between the motor hand areas is the mechanism by which Mirror visual feedback recruits the representation of the non-Mirrored limb. Therefore, Mirror illusion capacity and brain activations were measured in a within-subject design during both Mirror visual feedback conditions in counterbalanced order with 20 healthy subjects inside a magnetic resonance imaging scanner. Furthermore, we analyzed task-dependent functional connectivity between motor hand representations using psychophysiological interaction analysis during both Mirror tasks. Neither the subjective quality of Mirror illusions nor the patterns of functional brain activation differed between the Mirror tasks. The sensorimotor representation of the non-Mirrored hand was recruited in both Mirror tasks. However, a significant increase in interhemispheric connectivity between the hand areas was only observed in the Mirror glasses condition, suggesting different mechanisms for the recruitment of the representation of the non-Mirrored hand in the two Mirror tasks. We conclude that the Mirror glasses might be a promising alternative to the Mirror Box, as they induce similar patterns of brain activation. Moreover, the Mirror glasses can be easy applied in therapy and research. We want to emphasize that the neuronal mechanisms for the recruitment of the affected limb representation might differ depending on conceptual differences between MVF devices. However, our findings need to be validated within specific patient groups.
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Illusion-related brain activations: A new virtual reality Mirror Box system for use during functional magnetic resonance imaging
Brain Research, 2015Co-Authors: Martin Diers, Pinar Kirsch, Joerg Trojan, Felix Bach, Jens Foell, Robin Bekrater-bodmann, Sandra Kamping, Xaver Fuchs, Mariela Rance, Heiko MaassAbstract:Extended viewing of movements of one's intact limb in a Mirror as well as motor imagery have been shown to decrease pain in persons with phantom limb pain or complex regional pain syndrome and to increase the movement ability in hemiparesis following stroke. In addition, Mirrored movements differentially activate sensorimotor cortex in amputees with and without phantom limb pain. However, using a so-called Mirror Box has technical limitations, some of which can be overcome by virtual reality applications. We developed a virtual reality Mirror Box application and evaluated its comparability to a classical Mirror Box setup. We applied both paradigms to 20 healthy controls and analyzed vividness and authenticity of the illusion as well as brain activation patterns. In both conditions, subjects reported similar intensities for the sensation that movements of the virtual left hand felt as if they were executed by their own left hand. We found activation in the primary sensorimotor cortex contralateral to the actual movement, with stronger activation for the virtual reality 'Mirror Box' compared to the classical Mirror Box condition, as well as activation in the primary sensorimotor cortex contralateral to the Mirrored/virtual movement. We conclude that a virtual reality application of the Mirror Box is viable and that it might be useful for future research.
Martin Diers - One of the best experts on this subject based on the ideXlab platform.
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assessment of cortical reorganization and preserved function in phantom limb pain a methodological perspective
Scientific Reports, 2020Co-Authors: Jamila Andoh, Martin Diers, Xaver Fuchs, Christopher Milde, Jorg Trojan, Robin BekraterbodmannAbstract:Phantom limb pain (PLP) has been associated with reorganization in primary somatosensory cortex (S1) and preserved S1 function. Here we examined if methodological differences in the assessment of cortical representations might explain these findings. We used functional magnetic resonance imaging during a virtual reality movement task, analogous to the classical Mirror Box task, in twenty amputees with and without PLP and twenty matched healthy controls. We assessed the relationship between task-related activation maxima and PLP intensity in S1 and motor cortex (M1) in individually-defined or group-conjoint regions of interest (ROI) (overlap of task-related activation between the groups). We also measured cortical distances between both locations and correlated them with PLP intensity. Amputees compared to controls showed significantly increased activation in M1, S1 and S1M1 unrelated to PLP. Neural activity in M1 was positively related to PLP intensity in amputees with PLP when a group-conjoint ROI was chosen. The location of activation maxima differed between groups in S1 and M1. Cortical distance measures were unrelated to PLP. These findings suggest that sensory and motor maps differentially relate to PLP and that methodological differences might explain discrepant findings in the literature.
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assessment of cortical reorganization and preserved function in phantom limb pain a methodological perspective
arXiv: Neurons and Cognition, 2019Co-Authors: Jamila Andoh, Martin Diers, Xaver Fuchs, Christopher Milde, Jorg Trojan, Robin BekraterbodmannAbstract:Phantom limb pain (PLP) has been associated with both the reorganization of the somatotopic map in primary somatosensory cortex (S1) and preserved S1 function. Here we assessed the nature of the information (sensory, motor) that reaches S1 and methodological differences in the assessment of cortical representations that might explain these findings. We used functional magnetic resonance imaging during a virtual hand motor task, analogous to the classical Mirror Box task, in amputees with and without PLP and in matched controls. We assessed the relationship between task-related activation maxima and PLP intensity in S1 versus motor (M1) maps. We also measured cortical distances between the location of activation maxima using region of interest (ROI), defined from individual or group analyses. Amputees showed significantly increased activity in M1 and S1 compared to controls, which was not significantly related to PLP intensity. The location of activation maxima differed between groups depending on M1 and S1 maps. Neural activity was positively related to PLP only in amputees with pain and only if a group-defined ROI was chosen. These findings show that the analysis of changes in S1 versus M1 yields different results, possibly indicating different pain-related processes.
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do Mirror glasses have the same effect on brain activity as a Mirror Box evidence from a functional magnetic resonance imaging study with healthy subjects
PLOS ONE, 2015Co-Authors: Christopher Milde, Pinar Kirsch, Jens Foell, Xaver Fuchs, Mariela Rance, Jorg Trojan, Robin Bekraterbodmann, Herta Flor, Martin DiersAbstract:Since its original proposal, Mirror therapy has been established as a successful neurorehabilitative intervention in several neurological disorders to recover motor function or to relieve pain. Mirror therapy seems to operate by reactivating the contralesional representation of the non-Mirrored limb in primary motor- and somatosensory cortex. However, Mirror Boxes have some limitations which prompted the use of additional Mirror visual feedback devices. The present study evaluated the utility of Mirror glasses compared to a Mirror Box. We also tested the hypothesis that increased interhemispheric communication between the motor hand areas is the mechanism by which Mirror visual feedback recruits the representation of the non-Mirrored limb. Therefore, Mirror illusion capacity and brain activations were measured in a within-subject design during both Mirror visual feedback conditions in counterbalanced order with 20 healthy subjects inside a magnetic resonance imaging scanner. Furthermore, we analyzed task-dependent functional connectivity between motor hand representations using psychophysiological interaction analysis during both Mirror tasks. Neither the subjective quality of Mirror illusions nor the patterns of functional brain activation differed between the Mirror tasks. The sensorimotor representation of the non-Mirrored hand was recruited in both Mirror tasks. However, a significant increase in interhemispheric connectivity between the hand areas was only observed in the Mirror glasses condition, suggesting different mechanisms for the recruitment of the representation of the non-Mirrored hand in the two Mirror tasks. We conclude that the Mirror glasses might be a promising alternative to the Mirror Box, as they induce similar patterns of brain activation. Moreover, the Mirror glasses can be easy applied in therapy and research. We want to emphasize that the neuronal mechanisms for the recruitment of the affected limb representation might differ depending on conceptual differences between MVF devices. However, our findings need to be validated within specific patient groups.
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Illusion-related brain activations: A new virtual reality Mirror Box system for use during functional magnetic resonance imaging
Brain Research, 2015Co-Authors: Martin Diers, Pinar Kirsch, Joerg Trojan, Felix Bach, Jens Foell, Robin Bekrater-bodmann, Sandra Kamping, Xaver Fuchs, Mariela Rance, Heiko MaassAbstract:Extended viewing of movements of one's intact limb in a Mirror as well as motor imagery have been shown to decrease pain in persons with phantom limb pain or complex regional pain syndrome and to increase the movement ability in hemiparesis following stroke. In addition, Mirrored movements differentially activate sensorimotor cortex in amputees with and without phantom limb pain. However, using a so-called Mirror Box has technical limitations, some of which can be overcome by virtual reality applications. We developed a virtual reality Mirror Box application and evaluated its comparability to a classical Mirror Box setup. We applied both paradigms to 20 healthy controls and analyzed vividness and authenticity of the illusion as well as brain activation patterns. In both conditions, subjects reported similar intensities for the sensation that movements of the virtual left hand felt as if they were executed by their own left hand. We found activation in the primary sensorimotor cortex contralateral to the actual movement, with stronger activation for the virtual reality 'Mirror Box' compared to the classical Mirror Box condition, as well as activation in the primary sensorimotor cortex contralateral to the Mirrored/virtual movement. We conclude that a virtual reality application of the Mirror Box is viable and that it might be useful for future research.
Angelo Maravita - One of the best experts on this subject based on the ideXlab platform.
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back in control of intentional action improvement of ideomotor apraxia by Mirror Box treatment
Neuropsychologia, 2021Co-Authors: Daniele Romano, Giorgia Tosi, Valeria Gobbetto, P Pizzagalli, Renato Avesani, Valentina Moro, Angelo MaravitaAbstract:Abstract Objectives A novel method of rehabilitation for ideomotor apraxia (IMA), using a modified version of the Mirror Box (MB), is proposed. The rationale is based on the theory that disrupted body representation occurs in IMA and that MB training may improve body representation. In the present MB training, patients observed and reproduced movements made by the experimenter in a Mirror. The visual perspective gave the illusory sensation of seeing one's own affected hand in the Mirror. Methods Thirteen patients were included in the study; apraxia was measured four times: i) at baseline; ii) after a week of unspecific poststroke rehabilitation (rest); iii) after a week of imitation training for apraxia, used as a control; and iv) after a week of MB training. Imitation and Mirror Box training were presented in counterbalanced order between participants. The effect of the Mirror Box on a measure of body representation was also assessed. Results The results show that MB training improved apraxia when compared to the outcomes in both the imitation and rest conditions. The improvement correlates with the impact of the Mirror Box on the body representation (i.e., the degree of embodiment). Conclusions MB training shows promising effects in promoting recovery from apraxia. The hypothesis is that the Mirror Box triggers a quickly generated sense of embodiment of the reflected moving arm into the observer's body representation. This embodiment of the visuomotor features of the observed movements would positively affect motor programming, promoting motor improvement. Crucially, this effect seems to extend to actions performed outside the Mirror Box setup, enhancing patients' performance on an apraxia test.
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Mirror Box training in hemiplegic stroke patients affects body representation
Frontiers in Human Neuroscience, 2018Co-Authors: Giorgia Tosi, Daniele Romano, Angelo MaravitaAbstract:The brain integrates multisensory inputs coming from the body (i.e. proprioception, tactile sensations) and the world that surrounds it (e.g. visual information). In this way, it is possible to build supra-modal and coherent mental representations of our own body, in order to process sensory events and to plan movements and actions in space. Post-stroke acquired motor deficits affect the ability to move body parts and to interact with objects. This may, in turn, impair the brain representation of the affected body part, resulting in a further increase of disability and motor impairment. To the aim of improving any putative derangements of body representation induced by the motor deficit, here we used the Mirror Box (MB). MB is a rehabilitative tool aimed at restoring several pathological conditions where body representation is affected, including post-stroke motor impairments. In this setting, observing the reflection of the intact limb in the Mirror, while the affected one is hidden behind the Mirror, can exert a positive influence upon different clinical conditions from chronic pain to motor deficits. Such results are thought to be mediated by a process of embodiment of the Mirror reflection, which would be integrated into the representation of the affected limb. A group of 45 post-stroke patients was tested before and after performing a MB motor training in two conditions, one with the Mirror between the hands and one without it, so that patients could see their impaired limb directly. A forearm bisection task, specifically designed to measures the metric representation of the body (i.e. size), was used as dependent variable. Results showed that, at baseline, the forearm bisection is shifted proximally, compatibly with a shrink of the metric representation of the affected arm towards the shoulder. However, following the MB session bisection scores shifted distally, compatibly with a partial correction of the metric representation of that arm. The effects showed some variability with the laterality of the lesion and the duration of the illness. The present results call for a possible role of the MB as a tool for improving altered body representation following post-stroke motor impairments.
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controlling the alien hand through the Mirror Box a single case study of alien hand syndrome
Neurocase, 2014Co-Authors: Daniele Romano, Giangiacomo Beretta, Anna Sedda, Roberta Dellaquila, Dalla D Costa, Angelo Maravita, Gabriella BottiniAbstract:Disruption of motor control in the alien hand syndrome might result from a dissociation between intentions and sensory information. We hypothesized that voluntary motor control in this condition could improve by restoring the congruency between motor intentions and visual feedback. The present study shows that, in one patient with right alien hand syndrome, the use of a Mirror Box paradigm improved motor speed. We speculate that the visual feedback provided by the Mirror increases the sense of congruence between intention and sensory feedback, leading to motor improvement.
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perceptual effects of the Mirror Box training in normal subjects
Restorative Neurology and Neuroscience, 2013Co-Authors: Daniele Romano, Gabriella Bottini, Angelo MaravitaAbstract:Background and purpose The Mirror Box (MB) was developed in the early 1990 s to relieve phantom limb sensations and chronic pain. Although its efficacy has been shown in several clinical populations, the mechanisms underpinning effects still have to be fully understood. Methods 48 healthy subjects participated in 4 behavioral experiments where kinesthetic sensitivity of the hand inside the MB was tested during the observation of Mirror-reflected finger movements, executed with the hand outside the MB. Results We identified two effects on the hand hidden inside the MB: diminished kinesthetic sensitivity for passive movements, and the occurrence of unconscious, involuntary movements with the finger inside the Box, suggesting reduced motor awareness. Such sensory-motor effects were somatotopically specific to the finger moved, were influenced by the contextual presence of the whole hand in the Mirror, and occurred for both active and passive movements of the hand outside the MB. Conclusions The present results suggest that the MB induce a somatotopically and contextually specific overriding of kinesthetic control by vision, compatible with a process of embodiment of the Mirror-reflected hand image and provide novel clues to the understanding of the mechanisms underlying MB effects.
Daniele Romano - One of the best experts on this subject based on the ideXlab platform.
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back in control of intentional action improvement of ideomotor apraxia by Mirror Box treatment
Neuropsychologia, 2021Co-Authors: Daniele Romano, Giorgia Tosi, Valeria Gobbetto, P Pizzagalli, Renato Avesani, Valentina Moro, Angelo MaravitaAbstract:Abstract Objectives A novel method of rehabilitation for ideomotor apraxia (IMA), using a modified version of the Mirror Box (MB), is proposed. The rationale is based on the theory that disrupted body representation occurs in IMA and that MB training may improve body representation. In the present MB training, patients observed and reproduced movements made by the experimenter in a Mirror. The visual perspective gave the illusory sensation of seeing one's own affected hand in the Mirror. Methods Thirteen patients were included in the study; apraxia was measured four times: i) at baseline; ii) after a week of unspecific poststroke rehabilitation (rest); iii) after a week of imitation training for apraxia, used as a control; and iv) after a week of MB training. Imitation and Mirror Box training were presented in counterbalanced order between participants. The effect of the Mirror Box on a measure of body representation was also assessed. Results The results show that MB training improved apraxia when compared to the outcomes in both the imitation and rest conditions. The improvement correlates with the impact of the Mirror Box on the body representation (i.e., the degree of embodiment). Conclusions MB training shows promising effects in promoting recovery from apraxia. The hypothesis is that the Mirror Box triggers a quickly generated sense of embodiment of the reflected moving arm into the observer's body representation. This embodiment of the visuomotor features of the observed movements would positively affect motor programming, promoting motor improvement. Crucially, this effect seems to extend to actions performed outside the Mirror Box setup, enhancing patients' performance on an apraxia test.
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Mirror Box training in hemiplegic stroke patients affects body representation
Frontiers in Human Neuroscience, 2018Co-Authors: Giorgia Tosi, Daniele Romano, Angelo MaravitaAbstract:The brain integrates multisensory inputs coming from the body (i.e. proprioception, tactile sensations) and the world that surrounds it (e.g. visual information). In this way, it is possible to build supra-modal and coherent mental representations of our own body, in order to process sensory events and to plan movements and actions in space. Post-stroke acquired motor deficits affect the ability to move body parts and to interact with objects. This may, in turn, impair the brain representation of the affected body part, resulting in a further increase of disability and motor impairment. To the aim of improving any putative derangements of body representation induced by the motor deficit, here we used the Mirror Box (MB). MB is a rehabilitative tool aimed at restoring several pathological conditions where body representation is affected, including post-stroke motor impairments. In this setting, observing the reflection of the intact limb in the Mirror, while the affected one is hidden behind the Mirror, can exert a positive influence upon different clinical conditions from chronic pain to motor deficits. Such results are thought to be mediated by a process of embodiment of the Mirror reflection, which would be integrated into the representation of the affected limb. A group of 45 post-stroke patients was tested before and after performing a MB motor training in two conditions, one with the Mirror between the hands and one without it, so that patients could see their impaired limb directly. A forearm bisection task, specifically designed to measures the metric representation of the body (i.e. size), was used as dependent variable. Results showed that, at baseline, the forearm bisection is shifted proximally, compatibly with a shrink of the metric representation of the affected arm towards the shoulder. However, following the MB session bisection scores shifted distally, compatibly with a partial correction of the metric representation of that arm. The effects showed some variability with the laterality of the lesion and the duration of the illness. The present results call for a possible role of the MB as a tool for improving altered body representation following post-stroke motor impairments.
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controlling the alien hand through the Mirror Box a single case study of alien hand syndrome
Neurocase, 2014Co-Authors: Daniele Romano, Giangiacomo Beretta, Anna Sedda, Roberta Dellaquila, Dalla D Costa, Angelo Maravita, Gabriella BottiniAbstract:Disruption of motor control in the alien hand syndrome might result from a dissociation between intentions and sensory information. We hypothesized that voluntary motor control in this condition could improve by restoring the congruency between motor intentions and visual feedback. The present study shows that, in one patient with right alien hand syndrome, the use of a Mirror Box paradigm improved motor speed. We speculate that the visual feedback provided by the Mirror increases the sense of congruence between intention and sensory feedback, leading to motor improvement.
-
perceptual effects of the Mirror Box training in normal subjects
Restorative Neurology and Neuroscience, 2013Co-Authors: Daniele Romano, Gabriella Bottini, Angelo MaravitaAbstract:Background and purpose The Mirror Box (MB) was developed in the early 1990 s to relieve phantom limb sensations and chronic pain. Although its efficacy has been shown in several clinical populations, the mechanisms underpinning effects still have to be fully understood. Methods 48 healthy subjects participated in 4 behavioral experiments where kinesthetic sensitivity of the hand inside the MB was tested during the observation of Mirror-reflected finger movements, executed with the hand outside the MB. Results We identified two effects on the hand hidden inside the MB: diminished kinesthetic sensitivity for passive movements, and the occurrence of unconscious, involuntary movements with the finger inside the Box, suggesting reduced motor awareness. Such sensory-motor effects were somatotopically specific to the finger moved, were influenced by the contextual presence of the whole hand in the Mirror, and occurred for both active and passive movements of the hand outside the MB. Conclusions The present results suggest that the MB induce a somatotopically and contextually specific overriding of kinesthetic control by vision, compatible with a process of embodiment of the Mirror-reflected hand image and provide novel clues to the understanding of the mechanisms underlying MB effects.
Jens Foell - One of the best experts on this subject based on the ideXlab platform.
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do Mirror glasses have the same effect on brain activity as a Mirror Box evidence from a functional magnetic resonance imaging study with healthy subjects
PLOS ONE, 2015Co-Authors: Christopher Milde, Pinar Kirsch, Jens Foell, Xaver Fuchs, Mariela Rance, Jorg Trojan, Robin Bekraterbodmann, Herta Flor, Martin DiersAbstract:Since its original proposal, Mirror therapy has been established as a successful neurorehabilitative intervention in several neurological disorders to recover motor function or to relieve pain. Mirror therapy seems to operate by reactivating the contralesional representation of the non-Mirrored limb in primary motor- and somatosensory cortex. However, Mirror Boxes have some limitations which prompted the use of additional Mirror visual feedback devices. The present study evaluated the utility of Mirror glasses compared to a Mirror Box. We also tested the hypothesis that increased interhemispheric communication between the motor hand areas is the mechanism by which Mirror visual feedback recruits the representation of the non-Mirrored limb. Therefore, Mirror illusion capacity and brain activations were measured in a within-subject design during both Mirror visual feedback conditions in counterbalanced order with 20 healthy subjects inside a magnetic resonance imaging scanner. Furthermore, we analyzed task-dependent functional connectivity between motor hand representations using psychophysiological interaction analysis during both Mirror tasks. Neither the subjective quality of Mirror illusions nor the patterns of functional brain activation differed between the Mirror tasks. The sensorimotor representation of the non-Mirrored hand was recruited in both Mirror tasks. However, a significant increase in interhemispheric connectivity between the hand areas was only observed in the Mirror glasses condition, suggesting different mechanisms for the recruitment of the representation of the non-Mirrored hand in the two Mirror tasks. We conclude that the Mirror glasses might be a promising alternative to the Mirror Box, as they induce similar patterns of brain activation. Moreover, the Mirror glasses can be easy applied in therapy and research. We want to emphasize that the neuronal mechanisms for the recruitment of the affected limb representation might differ depending on conceptual differences between MVF devices. However, our findings need to be validated within specific patient groups.
-
Illusion-related brain activations: A new virtual reality Mirror Box system for use during functional magnetic resonance imaging
Brain Research, 2015Co-Authors: Martin Diers, Pinar Kirsch, Joerg Trojan, Felix Bach, Jens Foell, Robin Bekrater-bodmann, Sandra Kamping, Xaver Fuchs, Mariela Rance, Heiko MaassAbstract:Extended viewing of movements of one's intact limb in a Mirror as well as motor imagery have been shown to decrease pain in persons with phantom limb pain or complex regional pain syndrome and to increase the movement ability in hemiparesis following stroke. In addition, Mirrored movements differentially activate sensorimotor cortex in amputees with and without phantom limb pain. However, using a so-called Mirror Box has technical limitations, some of which can be overcome by virtual reality applications. We developed a virtual reality Mirror Box application and evaluated its comparability to a classical Mirror Box setup. We applied both paradigms to 20 healthy controls and analyzed vividness and authenticity of the illusion as well as brain activation patterns. In both conditions, subjects reported similar intensities for the sensation that movements of the virtual left hand felt as if they were executed by their own left hand. We found activation in the primary sensorimotor cortex contralateral to the actual movement, with stronger activation for the virtual reality 'Mirror Box' compared to the classical Mirror Box condition, as well as activation in the primary sensorimotor cortex contralateral to the Mirrored/virtual movement. We conclude that a virtual reality application of the Mirror Box is viable and that it might be useful for future research.