@article{MehnertBrunettiSteinbrinketal.2013,
  author    = {Mehnert, Jan and Brunetti, Maddalena and Steinbrink, Jens and Niedeggen, Michael and Dohle, Christian},
  title     = {Effect of a mirror-like illusion on activation in the precuneus assessed with functional near-infrared spectroscopy},
  series = {Journal of biomedical optics},
  volume    = {18},
  journal   = {Journal of biomedical optics},
  number    = {6},
  publisher = {SPIE},
  address   = {Bellingham},
  issn      = {1083-3668},
  doi       = {10.1117/1.JBO.18.6.066001},
  pages     = {9},
  year      = {2013},
  abstract  = {Mirror therapy is a therapy to treat patients with pain syndromes or hemiparesis after stroke. However, the underlying neurophysiologic mechanisms are not clearly understood. In order to determine the effect of a mirror-like illusion (MIR) on brain activity using functional near-infrared spectroscopy, 20 healthy right-handed subjects were examined. A MIR was induced by a digital horizontal inversion of the subjects' filmed hand. Optodes were placed on the primary motor cortex (M1) and the occipito-parietal cortex (precuneus, PC). Regions of interest (ROI) were defined a priori based on previous results of similar studies and confirmed by the analysis of effect sizes. Analysis of variance of the ROI signal revealed a dissociated pattern: at the PC, the MIR caused a significant inversion of a hemispheric lateralization opposite to the perceived hand, independent of the moving hand. In contrast, activity in M1 showed lateralization opposite to the moving hand, but revealed no mirror effect. These findings extend our understanding on interhemispheric rivalry and indicate that a MIR is integrated into visuomotor coordination similar to normal view, irrespective of the hand that is actually performing the task. (C) 2013 Society of Photo-Optical Instrumentation Engineers (SPIE)},
  language  = {en}
}
@article{WangFritzschBernardingetal.2013,
  author    = {Wang, Jing and Fritzsch, Claire and Bernarding, Johannes and Krause, Thomas and Mauritz, Karl-Heinz and Brunetti, Maddalena and Dohle, Christian},
  title     = {Cerebral activation evoked by the mirror illusion of the hand in stroke patients compared to normal subjects},
  series = {Neurorehabilitation : an interdisciplinary journal},
  volume    = {33},
  journal   = {Neurorehabilitation : an interdisciplinary journal},
  number    = {4},
  publisher = {IOS Press},
  address   = {Amsterdam},
  issn      = {1053-8135},
  doi       = {10.3233/NRE-130999},
  pages     = {593 -- 603},
  year      = {2013},
  abstract  = {BACKGROUND: Mirror therapy (MT) was found to improve motor function after stroke, but its neural mechanisms remain unclear, especially in single stroke patients. OBJECTIVES: The following imaging study was designed to compare brain activation patterns evoked by the mirror illusion in single stroke patients with normal subjects. METHODS: Fifteen normal volunteers and five stroke patients with severe arm paresis were recruited. Cerebral activations during movement mirroring by means of a video chain were recorded with functional magnetic resonance imaging (fMRI). Single-subject analysis was performed using SPM 8. RESULTS: For normal subjects, ten and thirteen subjects displayed lateralized cerebral activations evoked by the mirror illusion while moving their right and left hand respectively. The magnitude of this effect in the precuneus contralateral to the seen hand was not dependent on movement speed or subjective experience. Negative correlation of activation strength with age was found for the right hand only. The activation pattern in stroke patients is comparable to that of normal subjects and present in four out of five patients. CONCLUSIONS: In summary, the mirror illusion can elicit cerebral activation contralateral to the perceived hand in the majority of single normal subjects, but not in all of them. This is similar even in stroke patients with severe hemiparesis.},
  language  = {en}
}
@article{WangFritzschBernardingetal.2013,
  author    = {Wang, Jing and Fritzsch, Claire and Bernarding, Johannes and Holtze, Susanne and Mauritz, Karl-Heinz and Brunetti, Maddalena and Dohle, Christian},
  title     = {A comparison of neural mechanisms in mirror therapy and movement observation therapy},
  series = {Journal of rehabilitation medicine : official journal of the UEMS European Board of Physical and Rehabilitation Medicine},
  volume    = {45},
  journal   = {Journal of rehabilitation medicine : official journal of the UEMS European Board of Physical and Rehabilitation Medicine},
  number    = {4},
  publisher = {Foundation for Rehabilitation Information},
  address   = {Uppsala},
  issn      = {1650-1977},
  doi       = {10.2340/16501977-1127},
  pages     = {410 -- 413},
  year      = {2013},
  abstract  = {Objective: To compare lateralized cerebral activations elicited during self-initiated movement mirroring and observation of movements. Subjects: A total of 15 right-handed healthy subjects, age range 22-56 years. Methods: Functional imaging study comparing movement mirroring with movement observation, in both hands, in an otherwise identical setting. Imaging data were analysed using statistical parametric mapping software, with significance threshold set at p<0.01 (false discovery rate) and a minimum cluster size of 20 voxels. Results: Movement mirroring induced additional activation in primary and higher-order visual areas strictly contralateral to the limb seen by the subject. There was no significant difference of brain activity when comparing movement observation of somebody else's right hand with left hand. Conclusion: Lateralized cerebral activations are elicited by inversion of visual feedback (movement mirroring), but not by movement observation.},
  language  = {en}
}
@article{FritzschWangdosSantosetal.2014,
  author    = {Fritzsch, Claire and Wang, Jing and dos Santos, Luara Ferreira and Mauritz, Karl-Heinz and Brunetti, Maddalena and Dohle, Christian},
  title     = {Different effects of the mirror illusion on motor and somatosensory processing},
  series = {Restorative neurology and neuroscience},
  volume    = {32},
  journal   = {Restorative neurology and neuroscience},
  number    = {2},
  publisher = {IOS Press},
  address   = {Amsterdam},
  issn      = {0922-6028},
  doi       = {10.3233/RNN-130343},
  pages     = {269 -- 280},
  year      = {2014},
  abstract  = {Purpose: Mirror therapy can improve motor and sensory functions, but effects of the mirror illusion on primary motor and somatosensory cortex could not be established consistently. Methods: Fifteen right handed healthy volunteers performed or observed a finger-thumb opposition task. Cerebral activations during normal movement (NOR), mirrored movement (MIR) and movement observation (OBS) by means of a video chain were recorded with functional magnetic resonance imaging (fMRI). Activation sizes in movement > static conditions were identified using SPM8 (p < 0.001, unc.) and attributed to predefined areas employing the Anatomy toolbox 1.8. Laterality indices for the responsive areas were calculated on the basis of the number of activated voxels. Results: Relevant bilateral BOLD responses were found in primary motor (M1) and somatosensory (S1 - BA 2, 3b and 3a) cortex, premotor and parietal areas and V5. When comparing MIR to NOR, no significant change of contralateral activation in M1 was found, but clearly at S1 with differences between hands. Conclusion: The mirror illusion does not elicit immediate changes in motor areas, yet there is a direct effect on somatosensory areas, especially for left hand movements. These results suggest different effects of mirror therapy on processing and rehabilitation of motor and sensory function.},
  language  = {en}
}