MUSE - music and stress fMRI study on the stress response and the stress-reducing effect of music - an analysis based on physiological and neuronal data

In the fMRI pilot study MUSE - music and stress the acoustic stimuli music and nature sounds are evaluated as a means of stress reduction. This neural data can be used to extend the results of previous work on the stress-reducing influence of music and nature sounds. Since stress is known to be an important risk factor for organic and mental diseases, research into new ways of reducing stress will make an important contribution to the development of new therapeutic approaches. To investigate stress reduction in more detail, stress induction first had to take place in the MRI scanner. The MR-stresstest was developed as a research method for this purpose and is based on the Trier Social Stress Test. It was developed on the basis of the ScanSTRESS paradigm in which stress and rest conditions alternate. During the experiment stress was induced by the presentation of math and rotation tasks, time pressure and the negative evaluation of a filmed jury. In addition to neural data, the hormones cortisol and alpha-amylase are sampled. Physiological parameters, such as skin conductance, respiratory rate, and heart rate are determined and questionnaires on subjective stress experience are conducted. The MR-stresstest thus combines different levels of stress induction and provides comprehensive insights into the interplay of hormonal regulatory circuits, physiological body responses and the psycho-social aspects of stress. Stress induction was successfully implemented at all levels. This was shown by an increase in the subjectively perceived stress level, cortisol and alpha-amylase levels, heart rate and respiratory rate and skin conductance under stress conditions of the experiment. This highlights the role of the autonomic nervous system and hypothalamic-pituitary-adrenocortical axis in the short-term and long-term stress response. Attenuation of the stress response was observed over the course of the experiment, therefore further development of the test design is recommended to avoid habituation effects. At the neural level, significant clusters are found in the thalamus, lingual gyrus, cingulate gyrus, inferior frontal gyrus, and temporal gyrus. Accordingly, an increase in central activity is prominent. In response to the stressful situation, attention is increased and the ability to orientate quickly is improved. The study was designed to compare the stress response between the two study groups (music/nature sounds). The assumption that listening to music would contribute to stress reduction to a greater extent than listening to nature sounds could not be confirmed. Both subgroups showed a reduction of the stress response after listening to music or nature sounds. To better classify these results, confounding factors and limitations of the study method will be discussed. The particular influence of the MRI scanner as an additional stressor on hormone release and the evaluation of acoustic stimuli will be addressed. In summary, the functionality of the MR-stresstest for the induction of stress under fMRI conditions was demonstrated. Music and natural sounds are equally suitable for stress reduction. This potential should be the focus of further clinical studies.