title: A Primary Role for Nucleus Accumbens and Related Limbic Network in Vocal Tics.
abstract: Inappropriate vocal expressions, e.g., vocal tics in Tourette syndrome, severely impact quality of life. Neural mechanisms underlying vocal tics remain unexplored because no established animal model representing the condition exists. We report that unilateral disinhibition of the nucleus accumbens (NAc) generates vocal tics in monkeys. Whole-brain PET imaging identified prominent, bilateral limbic cortico-subcortical activation. Local field potentials (LFPs) developed abnormal spikes in the NAc and the anterior cingulate cortex (ACC). Vocalization could occur without obvious LFP spikes, however, when phase-phase coupling of alpha oscillations were accentuated between the NAc, ACC, and the primary motor cortex. These findings contrasted with myoclonic motor tics induced by disinhibition of the dorsolateral putamen, where PET activity was confined to the ipsilateral sensorimotor system and LFP spikes always preceded motor tics. We propose that vocal tics emerge as a consequence of dysrhythmic alpha coupling between critical nodes in the limbic and motor networks. VIDEO ABSTRACT.
authors.affiliation: Systems Neuroscience and Movement Disorders Laboratory, Korea Brain Research Institute, Daegu 701-300, South Korea; Laboratory for Symbolic Cognitive Development, RIKEN Brain Science Institute, Wako, Saitama 351-0198, Japan; Systems Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan; Laboratory of Cognitive and Behavioral Neuroscience, Division of Biomedical Science, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan. Electronic address: kevin.mccairn@yahoo.com.
authors.forename: Kevin W
authors.initials: KW
authors.lastname: McCairn
authors.affiliation: Molecular Neuroimaging, Molecular Imaging Center, National Institute of Radiological Sciences, Chiba 263-8555, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Nagai
authors.affiliation: Molecular Neuroimaging, Molecular Imaging Center, National Institute of Radiological Sciences, Chiba 263-8555, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Hori
authors.affiliation: Systems Neuroscience and Movement Disorders Laboratory, Korea Brain Research Institute, Daegu 701-300, South Korea; Systems Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan.
authors.forename: Taihei
authors.initials: T
authors.lastname: Ninomiya
authors.affiliation: Molecular Neuroimaging, Molecular Imaging Center, National Institute of Radiological Sciences, Chiba 263-8555, Japan.
authors.forename: Erika
authors.initials: E
authors.lastname: Kikuchi
authors.affiliation: Systems Neuroscience and Movement Disorders Laboratory, Korea Brain Research Institute, Daegu 701-300, South Korea.
authors.forename: Ju-Young
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Molecular Neuroimaging, Molecular Imaging Center, National Institute of Radiological Sciences, Chiba 263-8555, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Suhara
authors.affiliation: Laboratory for Symbolic Cognitive Development, RIKEN Brain Science Institute, Wako, Saitama 351-0198, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Iriki
authors.affiliation: Molecular Neuroimaging, Molecular Imaging Center, National Institute of Radiological Sciences, Chiba 263-8555, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Minamimoto
authors.affiliation: Systems Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Takada
authors.affiliation: Laboratory for Symbolic Cognitive Development, RIKEN Brain Science Institute, Wako, Saitama 351-0198, Japan; Department of Physiology, Kansai Medical University School of Medicine, Hirakata, Osaka 573-1010, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Isoda
authors.affiliation: Systems Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan; Laboratory of Cognitive and Behavioral Neuroscience, Division of Biomedical Science, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Matsumoto
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D008032:Limbic System / Q000502:physiology*; D008253:Macaca mulatta; D008297:Male; D009415:Nerve Net / Q000502:physiology*; D009714:Nucleus Accumbens / Q000502:physiology*; D020323:Tics / Q000503:physiopathology*; D014828:Vocalization, Animal / Q000502:physiology*