Erweiterte Suche

Involuntary Monitoring of Sound Signals in Noise Is Reflected in the Human Auditory Evoked N1m Response

Constant sound sequencing as operationalized by repeated stimulation with tones of the same frequency has multiple effects. On the one hand, it activates mechanisms of habituation and refractoriness, which are reflected in the decrease of response amplitude of evoked responses. On the other hand, the constant sequencing acts as spectral cueing, resulting in tones being detected faster and more accurately. With the present study, by means of magnetoencephalography, we investigated the impact of repeated tone stimulation on the N1m auditory evoked fields, while listeners were distracted from the test sounds. We stimulated subjects with trains of either four tones of the same frequency, or with trains of randomly assigned frequencies. The trains were presented either in a silent or in a noisy background. In silence, the patterns of source strength decline originating from repeated stimulation suggested both, refractoriness as well as habituation as underlying mechanisms. In noise, in contrast, there was no indication of source strength decline. Furthermore, we found facilitating effects of constant sequencing regarding the detection of the single tones as indexed by a shortening of N1m latency. We interpret our findings as a correlate of a bottom-up mechanism that is constantly monitoring the incoming auditory information, even when voluntary attention is directed to a different modality.

Titel: Involuntary Monitoring of Sound Signals in Noise Is Reflected in the Human Auditory Evoked N1m Response
Verfasser: Lagemann, Lothar
Okamoto, Hidehiko
Teismann, Henning
Pantev, Christo
Organisation: FB 05: Medizinische Fakultät
Dokumenttyp: Artikel
Medientyp: Text
Erscheinungsdatum: 28.02.2012
Publikation in MIAMI: 21.02.2013
Datum der letzten Änderung: 21.08.2014
Quelle: PLoS ONE 7 (2012) 2, e31634
Fachgebiete: Biowissenschaften; Biologie
Lizenz: CC BY 2.5
Sprache: Englisch
Anmerkungen: Finanziert durch den Open-Access-Publikationsfonds 2011/2012 der Deutschen Forschungsgemeinschaft (DFG) und der Westfälischen Wilhelms-Universität Münster (WWU Münster).
Format: PDF-Dokument
URN: urn:nbn:de:hbz:6-77379424941
DOI: doi:10.1371/journal.pone.0031634