Auditory steady-state responses in fetuses: a study using fetal magnetoencephalography (fMEG)

Abstract

Event Abstract Back to Event Auditory steady-state responses in fetuses: a study using fetal magnetoencephalography (fMEG) Rossitza Draganova1*, Rathinaswamy Govindan2, Erick Ortiz1, Isabelle Kiefer3 and Hubert Preissl4, 5 1 University of Tuebingen, MEG-Center, Germany 2 University of Arkansas for Medical Sciences, Department of Obstetrics and Gynaecology, United States 3 University Hospital of Tuebingen, Department of Obstetrics and Genecology, Germany 4 University of Tubingen, MEG-Center,University Hospital, Germany 5 University of Arkansas for Medical Sciences, Department for Obstetrics and Gynecology, Medical College, United States Based on the preliminary studies, we have established that fMEG was an appropriate and useful method for the recording of fetal brain responses in relation to the development of cognitive functions in fetuses and newborns. In this study, we extend our paradigms and examine if fMEG will be an appropriate method for the recording of Auditory Steady-State Responses (ASSR) with brainstem and cortical origin. Our goal was to establish protocols and stimulation paradigms for the recording of fetal ASSR and to assess if this approach could be useful for evaluation of maturation and development of cortical and brainstem structures in fetuses. Twenty pregnant women between 30 and 38 gestational weeks participated in the study. For comparison, 5 subjects from 25 to 45 years old were also investigated using cortical MEG (cMEG). The fMEG system contains 156 primary magnetic sensors and the cMEG contains 275 sensors. We selectively presented 10 to 40 seconds long repeated amplitude modulated (AM) sounds to the maternal abdomen with an external intensity of 90dB, assuming that the intrauterine intensity reaching the fetus was about 65-70dB and 65dB SPL to the adult subjects. The carrier frequency was 500 Hz or white noise modulated by modulation frequencies (MF) of 1Hz, 2Hz, 4Hz, 8Hz. A coherence approach was used to assess the effect of the stimuli on the single trial activity. A maximal coherence at the modulation frequency, calculated by the spectral estimates of MEG signal and stimulus dataset, was a criterion for detection of fetal brain response at this frequency. The results showed that AM sounds and AM white noise elicit transient responses to the stimulus onset in adults as well as in fetuses. Adult’s subjects were able to generate ASSRs at all MF, whereas fetal ASSR were detected only at 2 and 4 Hz MF. AM sound stimuli evoked better fetal ASSR than AM white-noise. At least 40 periods of the MF in a single trial are necessary to evoke ASSR in fetuses. Conference: Biomag 2010 - 17th International Conference on Biomagnetism , Dubrovnik, Croatia, 28 Mar - 1 Apr, 2010. Presentation Type: Poster Presentation Topic: Fetal and neonatal biomagnetism Citation: Draganova R, Govindan R, Ortiz E, Kiefer I and Preissl H (2010). Auditory steady-state responses in fetuses: a study using fetal magnetoencephalography (fMEG). Front. Neurosci. Conference Abstract: Biomag 2010 - 17th International Conference on Biomagnetism . doi: 10.3389/conf.fnins.2010.06.00138 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: 25 Mar 2010; Published Online: 25 Mar 2010. * Correspondence: Rossitza Draganova, University of Tuebingen, MEG-Center, Tuebingen, Germany, rossitza.draganova@med.uni-tuebingen.de 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 Rossitza Draganova Rathinaswamy Govindan Erick Ortiz Isabelle Kiefer Hubert Preissl Google Rossitza Draganova Rathinaswamy Govindan Erick Ortiz Isabelle Kiefer Hubert Preissl Google Scholar Rossitza Draganova Rathinaswamy Govindan Erick Ortiz Isabelle Kiefer Hubert Preissl PubMed Rossitza Draganova Rathinaswamy Govindan Erick Ortiz Isabelle Kiefer Hubert Preissl 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.