title: Decreased Anterior Cingulate Cortex γ-Aminobutyric Acid in Youth With Tourette's Disorder.
abstract: γ-Aminobutyric acid has been implicated in the pathophysiology of Tourette's disorder. The present study primarily sought to examine in vivo γ-aminobutyric acid levels in the anterior cingulate cortex in psychotropic medication-free adolescents and young adults. Secondarily, we sought to determine associations between γ-aminobutyric acid in the anterior cingulate cortex and measures of tic severity, tic-related impairment, and anxiety and depression symptoms.
  
  
  
  γ-Aminobutyric acid levels were measured using proton magnetic resonance spectroscopy. Analysis of covariance compared γ-aminobutyric acid levels in 15 youth with Tourette's disorder (mean age = 15.0, S.D. = 2.7) and 36 healthy comparison subjects (mean age = 15.9, S.D. = 2.1). Within the Tourette disorder group, we examined correlations between γ-aminobutyric acid levels and tic severity and tic-related impairment, as well as anxiety and depression severity.
  
  
  
  Anterior cingulate cortex γ-aminobutyric acid levels were lower in participants with Tourette's disorder compared with control subjects. Within the Tourette disorder group, γ-aminobutyric acid levels did not correlate with any clinical measures.
  
  
  
  Our findings support a role for γ-aminobutyric acid in Tourette's disorder. Larger prospective studies will further elucidate this role.
authors.affiliation: Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York.
authors.forename: Rachel D
authors.initials: RD
authors.lastname: Freed
authors.affiliation: Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York; Nathan S. Kline Institute for Psychiatric Research, Orangeburg, New York.
authors.forename: Barbara J
authors.initials: BJ
authors.lastname: Coffey
authors.affiliation: Department of Radiology, Weill Medical College of Cornell University, New York, New York.
authors.forename: Xiangling
authors.initials: X
authors.lastname: Mao
authors.affiliation: Department of Radiology, Weill Medical College of Cornell University, New York, New York.
authors.forename: Nora
authors.initials: N
authors.lastname: Weiduschat
authors.affiliation: Department of Radiology, Weill Medical College of Cornell University, New York, New York.
authors.forename: Guoxin
authors.initials: G
authors.lastname: Kang
authors.affiliation: Department of Radiology, Weill Medical College of Cornell University, New York, New York.
authors.forename: Dikoma C
authors.initials: DC
authors.lastname: Shungu
authors.affiliation: Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York; Nathan S. Kline Institute for Psychiatric Research, Orangeburg, New York. Electronic address: vilma.gabbay@mssm.edu.
authors.forename: Vilma
authors.initials: V
authors.lastname: Gabbay
mesh_terms: D000293:Adolescent; D015415:Biomarkers / Q000378:metabolism; D002648:Child; D005260:Female; D006179:Gyrus Cinguli / Q000000981:diagnostic imaging* / Q000378:metabolism*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male; D005879:Tourette Syndrome / Q000000981:diagnostic imaging* / Q000378:metabolism*; D055815:Young Adult; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D005680:gamma-Aminobutyric Acid
keywords: GABA; MRS; Tourette's disorder; adolescents; children