title: Spatiotemporal properties of auditory intensity processing in multisensor MEG.
abstract: Loudness dependence of auditory evoked potentials (LDAEP) evaluates loudness processing in the human auditory system and is often altered in patients with psychiatric disorders. Previous research has suggested that this measure may be used as an indicator of the central serotonergic system through the highly serotonergic innervation of the auditory cortex. However, differences among the commonly used analysis approaches (such as source analysis and single electrode estimation) may lead to different results. Putatively due to discrepancies of the underlying structures being measured. Therefore, it is important to learn more about how and where in the brain loudness variation is processed. We conducted a detailed investigation of the LDAEP generators and their temporal dynamics by means of multichannel magnetoencephalography (MEG). Evoked responses to brief tones of five different intensities were recorded from 19 healthy participants. We used magnetic field tomography in order to appropriately localize superficial as well as deep source generators of which we conducted a time series analysis. The results showed that apart from the auditory cortex other cortical sources exhibited activation during the N1/P2 time window. Analysis of time courses in the regions of interest revealed a sequential cortical activation from primary sensory areas, particularly the auditory and somatosensory cortex to posterior cingulate cortex (PCC) and to premotor cortex (PMC). The additional activation within the PCC and PMC has implications on the analysis approaches used in LDAEP research.
authors.affiliation: Institute of Neuroscience and Medicine, INM 4, Research Centre Jülich, Germany; Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital of Psychiatry Zurich, Switzerland. Electronic address: c.wyss@fz-juelich.de.
authors.forename: C
authors.initials: C
authors.lastname: Wyss
authors.affiliation: Institute of Neuroscience and Medicine, INM 4, Research Centre Jülich, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Boers
authors.affiliation: Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital of Psychiatry Zurich, Switzerland.
authors.forename: W
authors.initials: W
authors.lastname: Kawohl
authors.affiliation: Institute of Neuroscience and Medicine, INM 4, Research Centre Jülich, Germany; Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Arrubla
authors.affiliation: Institute of Neuroscience and Medicine, INM 4, Research Centre Jülich, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Vahedipour
authors.affiliation: Institute of Neuroscience and Medicine, INM 4, Research Centre Jülich, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Dammers
authors.affiliation: Institute of Neuroscience and Medicine, INM 4, Research Centre Jülich, Germany; Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, Germany; JARA-Brain, Translational Medicine, Jülich, Germany.
authors.forename: I
authors.initials: I
authors.lastname: Neuner
authors.affiliation: Institute of Neuroscience and Medicine, INM 4, Research Centre Jülich, Germany; JARA-Brain, Translational Medicine, Jülich, Germany; Department of Neurology, RWTH Aachen University, Germany.
authors.forename: N J
authors.initials: NJ
authors.lastname: Shah
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001303:Auditory Cortex / Q000502:physiology*; D002540:Cerebral Cortex / Q000502:physiology*; D005072:Evoked Potentials, Auditory; D006801:Humans; D008144:Loudness Perception / Q000502:physiology*; D015225:Magnetoencephalography; D008297:Male; D055815:Young Adult
keywords: Auditory evoked potentials; Cz; Loudness dependence; Magnetoencephalography; Posterior cingulate cortex; Serotonergic system