title: Gamma band oscillations: a key to understanding schizophrenia symptoms and neural circuit abnormalities.
abstract: OBJECTIVE
  We review our current understanding of abnormal γ band oscillations in schizophrenia, their association with symptoms and the underlying cortical circuit abnormality, with a particular focus on the role of fast-spiking parvalbumin gamma-aminobutyric acid (GABA) neurons in the disease state.
  
  
  RESULTS
  Clinical electrophysiological studies of schizophrenia patients and pharmacological models of the disorder show an increase in spontaneous γ band activity (not stimulus-evoked) measures. These findings provide a crucial link between preclinical and clinical work examining the role of γ band activity in schizophrenia. MRI-based experiments measuring cortical GABA provides evidence supporting impaired GABAergic neurotransmission in schizophrenia patients, which is correlated with γ band activity level. Several studies suggest that stimulation of the cortical circuitry, directly or via subcortical structures, has the potential to modulate cortical γ activity, and improve cognitive function.
  
  
  CONCLUSIONS
  Abnormal γ band activity is observed in patients with schizophrenia and disease models in animals, and is suggested to underlie the psychosis and cognitive/perceptual deficits. Convergent evidence from both clinical and preclinical studies suggest the central factor in γ band abnormalities is impaired GABAergic neurotransmission, particularly in a subclass of neurons which express parvalbumin. Rescue of γ band abnormalities presents an intriguing option for therapeutic intervention.
authors.affiliation: Laboratory of Neuroscience, VA Boston Healthcare System and Department of Psychiatry, Harvard Medical School, Brockton, Massachusetts, USA.
authors.forename: James M
authors.initials: JM
authors.lastname: McNally
authors.forename: Robert W
authors.initials: RW
authors.lastname: McCarley
mesh_terms: D000818:Animals; D003072:Cognition Disorders / Q000378:metabolism / Q000503:physiopathology; D006801:Humans; D009474:Neurons / Q000378:metabolism*; D010320:Parvalbumins / Q000378:metabolism*; D011618:Psychotic Disorders / Q000378:metabolism / Q000503:physiopathology; D012559:Schizophrenia / Q000378:metabolism* / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D009435:Synaptic Transmission; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
chemical_list: D010320:Parvalbumins; D005680:gamma-Aminobutyric Acid