Lärmempfindlichkeit in Funktion und Struktur des Gehirns
Die Forschung wurde mit Hilfe von Fragebögen, kombiniert mit Magnet-und Elektroenzephalographie (MEG / EEG) und Magnetresonanztomographie (MRT) durchgeführt
Kurze Zusammenfassung der Dissertation von Marina Kliuchko – 2017
NOISE SENSITIVITY IN THE FUNCTION AND STRUCTURE OF THE BRAIN
Cognitive Brain Research Unit – Department of Psychology and Logopedics
Faculty of Medicine University of Helsinki, Finlan
6. Schlussfolgerungen
Lärmempfindlichkeit hat in der populationsbasierten Forschung große Beachtung gefunden als Risikofaktor für lärmbedingte Gesundheitsprobleme, aber Bestrebungen, die physiologischen Mechanismen zu erforschen gab es erstaunlicherweise nur wenige.
Die vorliegende Arbeit verwendete mehrere bildgebende Verfahren sowie Fragebögen, um die Wissenslücke zu schließen über die funktionellen und strukturellen neuralen Grundlagen von NS (=Noise Sentivity – Lärmempfindlichkeit)
Zusammenfassend weisen die Ergebnisse dieser Arbeit darauf hin, dass Lärmempfindlichkeit nicht nur auf Einstellungen oder psychologischen Faktoren basiert, sondern biologische Grundlagen hat. Darüber hinaus macht diese Studie deutlich, dass die Bildgebung im Gehirn ein vielversprechender Weg ist, den Mechanismus zu erforschen, der zu individueller Lärmempfindlichkeit führt und auf welche Weise sie die Gesundheit beeinträchtigt.
Abstract
Exposure to noise has a negative influence on human health, including an increased occurrence of cardiovascular diseases. Susceptibility to the harmful effects of noise can be further moderated by a personal trait called noise sensitivity (NS). It is not understood what makes some individuals more sensitive to noise than others. So far, the research on this topic has been largely limited to perceptual and population studies. The aim of this thesis was to
broaden the understanding of NS by addressing its biological mechanisms.
Thus, this thesis investigated the neuroanatomical correlates of NS and its effects on auditory processing.
The thesis consists of three studies. The first study examines whether NS can be developed as the result of musical training (Study I). The other two studies investigate whether NS is reflected in the functioning of the central auditory system (Study II) and whether it is related to the morphology of cortical and subcortical brain structures (Study III).
The research was conducted using questionnaires, combined magneto- and electroencephalography (MEG/EEG) and magnetic resonance imaging (MRI).
The findings of this thesis suggest that NS moderates how and why individuals listen to music. However, NS is not associated with musical training and thus does not seem to relate to fine perceptual skills (Study I). An investigation of the central auditory processing in Study II, however, revealed compromised sound feature encoding and automatic discrimination skills in noise-sensitive individuals. Study III showed that NS is also associated with the structural organization of the brain. Noise-sensitive individuals were found to have enlarged volumes of the auditory cortical areas and hippocampus as well as thicker right anterior insular cortex. These results suggest that NS is related to the structures involved with auditory perceptual, emotional, and interoceptive processing. Overall, this thesis proposes that NS is not merely an attitudinal phenomenon but instead has underlying neuronal mechanisms.
Conclusion
Study I
showed that NS is not increased in musicians as compared to non-musicians and music amateurs. However, NS moderates background listening to music as the higher NS corresponded to fewer hours spent by an individual having music in the background.
Study II
used EEG/MEG to investigate pre-attentive stages of the central auditory processing in NS. The findings showed that individuals with high NS, as compared to those with low NS, had compromised neural sound feature encoding, followed by smaller neurophysiological responses to sound feature deviations, especially in the case of the noise deviant. This conclusion is supported with the results of
Study III
where structural MRI analysis was employed to learn about the neural substrate of NS. There it was found that NS is associated with enlarged core auditory cortical areas, such as the left Heschl’s sulcus. Furthermore, the findings on the relationship of NS with brain morphology were not restricted to auditory-related cortex. NS was positively correlated with thickness of the right anterior insula as well as with grey matter volume of the hippocampus and temporal pole in both hemispheres. These areas have been previously linked to auditory processing, aversive learning and emotional evaluation as well as binding internal and external sensory information.
Taken together the results of this thesis indicate that NS does not relate only to attitudinal or psychological factors but has biological underpinnings.
Moreover, this thesis makes it evident that brain imaging is a promising way of studying the mechanism by which individuals are noise-sensitive and how that leads to impaired health.
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https://helda.helsinki.fi/bitstream/handle/10138/217878/NOISESEN.pdf?sequence=1
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With thanks to Mauri, Finland/Denmark!
Zur Erinnerung: Ähnliche Untersuchungen, hier zum Thema ‘Auswirkungen von Infraschall auf die Hirnaktivität’, wurden auch in Deutschland durchgeführt!
Bitte beachten Sie die Weichenberger-Studie von Forschern der Charité, PTB und des UKE aus 2016/17!
[box title=”” border_width=”3″ border_color=”#70ad00″ border_style=”solid” icon=”exclamation” icon_style=”border” icon_shape=”box” align=”justify” text_color=”#000000″]”MRT-Beweis:
Infraschall verändert die kortikale und subkortikale Konnektivität nahe der Hörschwelle –
Veränderte kortikale und subkortikale Konnektivität durch Infraschalleinwirkung nahe der Hörschwelle – Nachweis aus fMRI (funktionelle Magnetresonanztomographie)”
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