title: Gamma oscillations in V1 are correlated with GABA(A) receptor density: A multi-modal MEG and Flumazenil-PET study.
abstract: High-frequency oscillations in the gamma-band reflect rhythmic synchronization of spike timing in active neural networks. The modulation of gamma oscillations is a widely established mechanism in a variety of neurobiological processes, yet its neurochemical basis is not fully understood. Modeling, in-vitro and in-vivo animal studies suggest that gamma oscillation properties depend on GABAergic inhibition. In humans, search for evidence linking total GABA concentration to gamma oscillations has led to promising -but also to partly diverging- observations. Here, we provide the first evidence of a direct relationship between the density of GABA(A) receptors and gamma oscillatory gamma responses in human primary visual cortex (V1). By combining Flumazenil-PET (to measure resting-levels of GABA(A) receptor density) and MEG (to measure visually-induced gamma oscillations), we found that GABA(A) receptor densities correlated positively with the frequency and negatively with amplitude of visually-induced gamma oscillations in V1. Our findings demonstrate that gamma-band response profiles of primary visual cortex across healthy individuals are shaped by GABA(A)-receptor-mediated inhibitory neurotransmission. These results bridge the gap with in-vitro and animal studies and may have future clinical implications given that altered GABAergic function, including dysregulation of GABA(A) receptors, has been related to psychiatric disorders including schizophrenia and depression.
authors.affiliation: Department of Neuroscience and Biomedical Engineering, Aalto University, 02150 Espoo, Finland.|Lyon Neuroscience Research Center, INSERM U1028-CNRS UMR5292, F-69000, Lyon, France.
authors.forename: Jan
authors.initials: J
authors.lastname: Kujala
authors.affiliation: Lyon Neuroscience Research Center, INSERM U1028-CNRS UMR5292, F-69000, Lyon, France.|Department of Epileptology and Functional Neurology, Lyon Neurological Hospital, F-69000, Lyon, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Jung
authors.affiliation: CERMEP imaging center, F-69003, Bron, France.|Institute for Child and Adolescent with Epilepsy (IDEE), F-69000, Lyon, France.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Bouvard
authors.affiliation: Lyon Neuroscience Research Center, INSERM U1028-CNRS UMR5292, F-69000, Lyon, France.|CERMEP imaging center, F-69003, Bron, France.
authors.forename: Françoise
authors.initials: F
authors.lastname: Lecaignard
authors.affiliation: Lyon Neuroscience Research Center, INSERM U1028-CNRS UMR5292, F-69000, Lyon, France.
authors.forename: Amélie
authors.initials: A
authors.lastname: Lothe
authors.affiliation: Lyon Neuroscience Research Center, INSERM U1028-CNRS UMR5292, F-69000, Lyon, France.
authors.forename: Romain
authors.initials: R
authors.lastname: Bouet
authors.affiliation: Lyon Neuroscience Research Center, INSERM U1028-CNRS UMR5292, F-69000, Lyon, France.|Institute for Child and Adolescent with Epilepsy (IDEE), F-69000, Lyon, France.
authors.forename: Carolina
authors.initials: C
authors.lastname: Ciumas
authors.affiliation: Lyon Neuroscience Research Center, INSERM U1028-CNRS UMR5292, F-69000, Lyon, France.|Institute for Child and Adolescent with Epilepsy (IDEE), F-69000, Lyon, France.|Department of Clinical Neurosciences, CHUV, 1011, Lausanne, Switzerland.
authors.forename: Philippe
authors.initials: P
authors.lastname: Ryvlin
authors.affiliation: Lyon Neuroscience Research Center, INSERM U1028-CNRS UMR5292, F-69000, Lyon, France.|Department of Psychology, University of Montreal, H3C 3J7 Montreal, Québec, Canada.
authors.forename: Karim
authors.initials: K
authors.lastname: Jerbi
mesh_terms: D000328:Adult; D005260:Female; D005442:Flumazenil / Q000737:chemistry*; D006801:Humans; D008279:Magnetic Resonance Imaging; D015225:Magnetoencephalography; D008297:Male; D049268:Positron-Emission Tomography; D011963:Receptors, GABA-A / Q000378:metabolism*; D014793:Visual Cortex / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
chemical_list: D011963:Receptors, GABA-A; D005442:Flumazenil; D005680:gamma-Aminobutyric Acid