Relating motor cortical oscillations to motor γ-Aminobutyric acid (GABA)

Field: Neuroscience (Life Sciences)

Event Abstract Back to Event Relating motor cortical oscillations to motor γ-Aminobutyric acid (GABA) William Gaetz1*, James C. Edgar1, D-J Wang1 and Timothy P. Roberts1 1 The Children's Hospital of Philadelphia and The University of Pennsylvania, Department of Radiology, United States Animal [1] and non-invasive human studies [2] demonstrate a strong relationship between cortical motor oscillations and the inhibitory neurotransmitter γ-Aminobutyric acid (GABA). A relationship between GABA concentration and cortical gamma oscillations was recently demonstrated in visual cortex [3]. Movement-related gamma (MRG), and post-movement beta rebound (PMBR) observed in humans may also depend on interneuronal GABA inhibitory currents [4]. Direct measures between motor cortex oscillations and motor cortex (MI) GABA, however, have not yet been demonstrated. The present study examined associations between PMBR and MRG and MI GABA. Adult subjects (N=8) made a right finger button response to a visual cue while whole-cortex MEG was obtained. PMBR (1-100 Hz) and PMG (65-90Hz) were estimated by first localizing contralateral MI using a differential SAM beamformer (Beta ERD; 15-30Hz). Time-frequency transforms were then applied to source waveforms from peak ERD locations, yielding frequency and power measures of PMBR and MRG oscillations. In the same subjects, single voxel (30x30x30mm) GABA magnetic response spectroscopy (MRS) was obtained using MEGA-PRESS. The MRS voxel was centered on the “hand-knob” of the left central sulcus. GABA measures were also obtained from a head coil reference phantom (50mM GABA). GABA levels were estimated as the ratio of the MI GABA integral to that of the phantom. PMBR power (% change) showed a marginally significant linear association with motor GABA concentration (r2 = 0.33, p=0.07). MRG frequency was associated with motor GABA concentration (r2 = 0.48, p=0.03). Present results support the hypothesis that motor cortical gamma power and frequency depend on MI GABA concentrations. References 1. Yamawaki, N., Stanford, I.M., Hall, S.D., Woodhall, G.L., 2008. Pharmacologically induced and stimulus evoked rhythmic neuronal oscillatory activity in the primary motor cortex in vitro. Neuroscience 151, 386-395.2. Wanquier, A., 1998. EEG and neuropharmachology, in electroencephalography. Basic Principles, Clinical Applications, and Related Fields, 660â€“ 670.3. Muthukumaraswamy SD, Edden RA, Jones DK, Swettenham JB, Singh KD. (2009). Resting GABA concentration predicts peak gamma frequency and fMRI amplitude in response to visual stimulation in humans. PNAS, (2009).4. Chen, R., Corwell, B., Hallett, M., 1999. Modulation of motor cortex excitability by median nerve and digit stimulation. Exp Brain Res 129, 77-86. Conference: Biomag 2010 - 17th International Conference on Biomagnetism , Dubrovnik, Croatia, 28 Mar - 1 Apr, 2010. Presentation Type: Poster Presentation Topic: Sensory Processing and Functional Connectivity Citation: Gaetz W, Edgar JC, Wang D and Roberts TP (2010). Relating motor cortical oscillations to motor γ-Aminobutyric acid (GABA). Front. Neurosci. Conference Abstract: Biomag 2010 - 17th International Conference on Biomagnetism . doi: 10.3389/conf.fnins.2010.06.00156 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 26 Mar 2010; Published Online: 26 Mar 2010. * Correspondence: William Gaetz, The Children's Hospital of Philadelphia and The University of Pennsylvania, Department of Radiology, Philadelphia, United States, bill.gaetz@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers William Gaetz James C Edgar D-J Wang Timothy P Roberts Google William Gaetz James C Edgar D-J Wang Timothy P Roberts Google Scholar William Gaetz James C Edgar D-J Wang Timothy P Roberts PubMed William Gaetz James C Edgar D-J Wang Timothy P Roberts Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.