TY  - JOUR
A1  - Mehnert, Jan
A1  - Brunetti, Maddalena
A1  - Steinbrink, Jens
A1  - Niedeggen, Michael
A1  - Dohle, Christian
T1  - Effect of a mirror-like illusion on activation in the precuneus assessed with functional near-infrared spectroscopy
JF  - Journal of biomedical optics
N2  - 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)
KW  - functional near-infrared spectroscopy
KW  - optical imaging
KW  - mirror illusion
KW  - mirror therapy
KW  - precuneus
Y1  - 2013
U6  - https://doi.org/10.1117/1.JBO.18.6.066001
SN  - 1083-3668
VL  - 18
IS  - 6
PB  - SPIE
CY  - Bellingham
ER  - 
TY  - JOUR
A1  - Ulm, Lena
A1  - Wohlrapp, Dorota
A1  - Meinzer, Marcus
A1  - Steinicke, Robert
A1  - Schatz, Alexej
A1  - Denzler, Petra
A1  - Klehmet, Juliane
A1  - Dohle, Christian
A1  - Niedeggen, Michael
A1  - Meisel, Andreas
A1  - Winter, York
T1  - A circle-monitor for computerised assessment of visual neglect in peripersonal space
JF  - PLoS one
N2  - Current assessment of visual neglect involves paper-and-pencil tests or computer-based tasks. Both have been criticised because of their lack of ecological validity as target stimuli can only be presented in a restricted visual range. This study examined the user-friendliness and diagnostic strength of a new "Circle-Monitor" (CM), which enlarges the range of the peripersonal space, in comparison to a standard paper-and-pencil test (Neglect-Test, NET).
 Methods: Ten stroke patients with neglect and ten age-matched healthy controls were examined by the NET and the CM test comprising of four subtests (Star Cancellation, Line Bisection, Dice Task, and Puzzle Test).
 Results: The acceptance of the CM in elderly controls and neglect patients was high. Participants rated the examination by CM as clear, safe and more enjoyable than NET. Healthy controls performed at ceiling on all subtests, without any systematic differences between the visual fields. Both NET and CM revealed significant differences between controls and patients in Line Bisection, Star Cancellation and visuo-constructive tasks (NET: Figure Copying, CM: Puzzle Test). Discriminant analyses revealed cross-validated assignment of patients and controls to groups was more precise when based on the CM (hit rate 90%) as compared to the NET (hit rate 70%).
 Conclusion: The CM proved to be a sensitive novel tool to diagnose visual neglect symptoms quickly and accurately with superior diagnostic validity compared to a standard neglect test while being well accepted by patients. Due to its upgradable functions the system may also be a valuable tool not only to test for non-visual neglect symptoms, but also to provide treatment and assess its outcome.
Y1  - 2013
U6  - https://doi.org/10.1371/journal.pone.0082892
SN  - 1932-6203
VL  - 8
IS  - 12
PB  - PLoS
CY  - San Fransisco
ER  -