April 2017 | Volume 8 | Article 142 1 CASE REPORT published: 10 April 2017 doi: 10.3389/fneur.2017.00142 Frontiers in Neurology | www.frontiersin.org Edited by: Ayrton R. Massaro, Hospital Sirio-Libanes, Brazil Reviewed by: Christos Papadelis, Harvard Medical School, USA Bernadette Ann Murphy, University of Ontario Institute of Technology, Canada Rashid Giniatullin, University of Eastern Finland, Finland *Correspondence: Mircea Ariel Schoenfeld ariel.schoenfeld@med.ovgu.de Specialty section: This article was submitted to Neurology Education, a section of the journal Frontiers in Neurology Received: 19 December 2016 Accepted: 28 March 2017 Published: 10 April 2017 Citation: Büntjen L, Hopf J-M, Merkel C, Voges J, Knape S, Heinze H-J and Schoenfeld MA (2017) Somatosensory Misrepresentation Associated with Chronic Pain: Spatiotemporal Correlates of Sensory Perception in a Patient following a Complex Regional Pain Syndrome Spread. Front. Neurol. 8:142. doi: 10.3389/fneur.2017.00142 Somatosensory Misrepresentation Associated with Chronic Pain: Spatiotemporal Correlates of Sensory Perception in a Patient following a Complex Regional Pain Syndrome Spread Lars Büntjen 1 , Jens-Max Hopf 1,2,3 , Christian Merkel 3 , Jürgen Voges 1 , Stefan Knape 3 , Hans-Jochen Heinze 2,3 and Mircea Ariel Schoenfeld 2,3,4 * 1 Department of Stereotactic Neurosurgery, Otto-von-Guericke University, Magdeburg, Germany, 2 Leibniz Institute for Neurobiology, Magdeburg, Germany, 3 Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany, 4 Kliniken Schmieder Heidelberg and Lurija Institute, Allensbach, Germany Chronic pain is suggested to be linked to reorganization processes in the sensorimotor cortex. In the current study, the somatosensory representation of the extremities was investigated in a patient with a complex regional pain syndrome (CRPS) that initially occurred in the right hand and arm and spread later into the left hand and right leg. After the spread, magnetoencephalographic recordings in conjunction with somatosensory stimulation revealed that the clinical symptoms were associated with major changes in the primary somatosensory representation. Tactile stimulation of body parts triggering CRPS-related pain elicited activity located in the left primary somatosensory region corresponding to the right hand representation, where the CRPS initially appeared. Solely the unaffected left foot was observed to have a regular S1 representation. The pain distribution pattern was matching the cortical somatosensory misrepresentation suggesting that cortical reorganization processes might contribute and possibly underlie the development and spread of the CRPS. Keywords: complex regional pain syndrome, magnetencephalography, primary somatosensory cortex, cortical reorganization, pain spread INTRODUCTION Complex regional pain syndrome (CRPS) is characterized by severe pain, dysfunction, and disabil- ity. Te precise cause and pathophysiology are not known yet (1), and efective treatment options are limited and difcult (2). In the last decade, several reports emerged suggesting that the development, maintenance, and putative treatment of CRPS are associated with functional brain reorganization (3–6). In many studies, the primary somatosensory cortex (S1) showed changes with regard to the spatial organization but also to the magnitude of responses elicited by cutaneous stimulation [reviewed in Ref. (7)]. A recent meta-analysis revealed that the representation size of the afected hand in CRPS was smaller than that of healthy controls. One study showed a shorter distance between the representation of the lip and the hand in the afected S1 compared to the unafected