RESEARCH ARTICLE Sleep Deprivation Reveals Altered Brain Perfusion Patterns in Somnambulism Thien Thanh Dang-Vu 1,2,3 , Antonio Zadra 1,4 *, Marc-Antoine Labelle 4 , Dominique Petit 1 , Jean-Paul Soucy 5,6 , Jacques Montplaisir 1,7 * 1 Center for Advanced Research in Sleep Medicine, Hôpital du Sacré-Cœur de Montréal, Montréal, Quebec, Canada, 2 Center for Studies in Behavioral Neurobiology, PERFORM Center & Department of Exercise Science, Concordia University, Montréal, Quebec, Canada, 3 Centre de Recherche de l’Institut Universitaire de Gériatrie de Montréal and Department of Neurosciences, Université de Montréal, Montréal, Quebec, Canada, 4 Department of Psychology, Université de Montréal, Montréal, Quebec, Canada, 5 Montreal Neurological Institute, McGill University, Montréal, Quebec, Canada, 6 Department of Nuclear Medicine, Centre Hospitalier de l’Université de Montréal, Montréal, Québec, Canada, 7 Department of Psychiatry and Canada Research Chair in Sleep Medicine, Université de Montréal, Montréal, Quebec, Canada * antonio.zadra@umontreal.ca (AZ); jy.montplaisir@umontreal.ca (JM) Abstract Background Despite its high prevalence, relatively little is known about the pathophysiology of somnam- bulism. Increasing evidence indicates that somnambulism is associated with functional abnormalities during wakefulness and that sleep deprivation constitutes an important drive that facilitates sleepwalking in predisposed patients. Here, we studied the neural mecha- nisms associated with somnambulism using Single Photon Emission Computed Tomogra- phy (SPECT) with 99m Tc-Ethylene Cysteinate Dimer (ECD), during wakefulness and after sleep deprivation. Methods Ten adult sleepwalkers and twelve controls with normal sleep were scanned using 99m Tc- ECD SPECT in morning wakefulness after a full night of sleep. Eight of the sleepwalkers and nine of the controls were also scanned during wakefulness after a night of total sleep deprivation. Between-group comparisons of regional cerebral blood flow (rCBF) were per- formed to characterize brain activity patterns during wakefulness in sleepwalkers. Results During wakefulness following a night of total sleep deprivation, rCBF was decreased bilater- ally in the inferior temporal gyrus in sleepwalkers compared to controls. Conclusions Functional neural abnormalities can be observed during wakefulness in somnambulism, particularly after sleep deprivation and in the inferior temporal cortex. Sleep deprivation thus PLOS ONE | DOI:10.1371/journal.pone.0133474 August 4, 2015 1/9 OPEN ACCESS Citation: Dang-Vu TT, Zadra A, Labelle M-A, Petit D, Soucy J-P, Montplaisir J (2015) Sleep Deprivation Reveals Altered Brain Perfusion Patterns in Somnambulism. PLoS ONE 10(8): e0133474. doi:10.1371/journal.pone.0133474 Editor: Raffaele Ferri, Oasi research institute, ITALY Received: May 14, 2015 Accepted: June 28, 2015 Published: August 4, 2015 Copyright: © 2015 Dang-Vu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: Due to ethical restrictions, data are unsuitable for public deposition. Requests for data by researchers who meet the criteria for access to confidential data may be made to the Research Ethics Committee of the Hôpital du Sacré-Cœur de Montréal/Université de Montréal. Funding: This study was funded by the Canadian Institutes of Health Research (CIHR grant # MOP 97865). The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: One author of this manuscript has the following competing interests: JM. In the past