Research activities of the group “Brain-Body Interaction”

01/01/2018

72

Fonds National de la Recherche Luxembourg (FNR)

Ruta Müller; Claus Vögele; Ilse Van Diest; André Schulz

Somatic symptom disorders (SSD) are characterized by enduring physical symptoms without a sufficient medical explanation; they have a high lifetime prevalence of 4.4-12.9% and are associated with a significant impairment of quality of life. Although altered interoception, the processing of internal bodily signals, is observed in SSD, the psychobiology underlying symptom generation remains, however, unclear. Learning and memory associated with physical symptoms (i.e. interoceptive learning) may represent one key mechanism to explain symptom generation. As post-learning stress may facilitate (mainly declarative) learning and memory, this project aims at investigating stress facilitation effects on interoceptive learning and memory. As SSD patients show a bias in retrospective (declarative) symptom memory, indicating a low correspondence with actually experienced symptoms, this project focuses on two non-declarative learning paradigms: classical conditioning (CC) of interoceptive signals and heartbeat perception training (HBPT), which is considered a perceptual learning paradigm. In Studies I and II, we plan to investigate the possibly enhancing effect of post-learning stress on CC of interoceptive signals and on HBPT. According to existing literature on CC of exteroceptive signals and our own pre-studies, we expect a facilitation of learning processes after post-learning stress. In Study III, we aim at addressing possible differences in facilitation by post-learning stress between low (LSR) and high habitual symptom reporters (HSR), a high-risk group to develop SSDs. The contribution of both physiological stress axes (autonomic nervous system, hypothalamic-pituitary-adrenocortical axis) will be assessed in all studies. Due to chronic stress and possible alterations in physiological stress axes in HSR, we expect that post-learning stress facilitation of interoceptive learning is stronger in HSR than in LSR. This project may elucidate if stress effects on CC or perceptual learning underlies symptom generation in SSD and it may inform future treatment approaches for SSD, such as extinction learning therapy associated with interoceptive signals.

https://www.fnr.lu/projects/stress-effects-on-interoceptive-learning-and-memory-as-a-mechanism-of-somatic-symptom-generation/

01/12/2019

48

Research Support Department of the University of Luxembourg

Greta Hansen; Claus Vögele; Silja Bellingrath; André Schulz

Interoception, the perception of physical symptoms, plays an important role for health, stress and disease. Accurate interoception is associated with factors that contribute to mental health, such as emotion regulation or emotional experience. Disturbed interoception can be observed in mental disorders, which are associated with physical symptoms, such as panic disorder or somatoform disorders. Chronic stress represents a major risk factor for the development of those disorders. While interoception implies the perception of signals on the ascending brain-body axis, stress represents a prominent example for descending signals on the brain-body axis. Dysregulated signal transmission on the ascending and/or the descending branch of the brain-body axes may underlie the generation of physical symptoms. The effects of acute stress on interoception are well-documented. Nevertheless, since acute stress may be a model of only limited ecological validity, the aim of the current project is to investigate psychophysiological mechanism underlying interoception in chronic stress. We, therefore, intend to investigate highly stressed (HS) schoolteachers compared to a group of schoolteachers with low self-reported stress levels (LS). It is well established that the teaching profession represents a highly stressful occupation due to enduring psychosocial demands at the workplace. As a consequence, HS schoolteachers may show dysregulation in the reactivity of both physiological stress systems, namely (1) the autonomic nervous system (ANS), and (2) the hypothalamic-pituitary-adrenocortical (HPA) axis. The project comprises a multi-method approach to assess interoception including (1) heartbeat-evoked brain potentials, which are considered to reflect cortical processing of cardiac interoceptive neural signals, cardiac modulation of startle (CMS), which is assumed to index cardiac interoceptive signals at the level of the brainstem, and (3) heartbeat perception tasks to reflect attention focused on cardiac sensation. HS and LS Schoolteachers will be tested with these experimental paradigms during rest and after a social stressor. Furthermore, psychophysiological data used as indicators of ANS activity will be recorded during rest and in response to a stressor, as well as diurnal measurements of salivary cortisol. In summary, the current project aims at elucidating the contribution of both physiological stress systems for altered processing of physical symptoms in highly stressed schoolteachers.

15/05/2021

1

Fonds National de la Recherche Luxembourg (FNR); Fonds Wetensschappelijk Onderzoek – Vlaanderen (FWO)

Sam Bernard; Claus Vögele; Andreas von Leupoldt; Lukas Van Oudenhove; Natalie Weltens; Maaike Van Den Houte; Tabea Eimer; André Schulz

Interoception of bodily sensations across organ domains and its relevance for somatic symptoms (INBODY) – co-funded by the Research Foundation Flanders (FWO) and the Fonds National de la Recherche (FNR). Functional somatic syndromes (FSS) are characterized by chronic, disabling symptoms that do not correspond to observable organic dysfunction, and come at great individual and societal costs. Treatment options for FSS are limited, which is largely due to insufficient knowledge about the mechanisms underlying these symptoms. Disturbed interoception, the ability to process and perceive sensory signals from within the body, is believed to be crucially involved. Therefore, the present project aims to examine several important aspects of interoception in healthy individuals and patients with FSS. Specifically, we will investigate whether interoception is a general ability that shares neural processing characteristics across multiple organ domains and that predicts affective responses. Moreover, we will test whether altered interoceptive processing of bodily signals from different organs can explain the heterogeneity of somatic symptoms, especially in FSS, and how this can be modified by new treatment approaches. Our multidisciplinary research team combines expertise from the fields of psychology, neuroscience and gastroenterology. In interrelated observational and experimental work packages, we will combine state-of-the-art methods including psychophysiological, neural and behavioural measures to improve the understanding of interoception within and across multiple organ domains and to establish interoception-based intervention strategies to reduce symptom burden in FSS patients.

https://www.fnr.lu/international-cooperation-round-up-of-2020-retained-inter-projects/

01/04/2022

48

Institute for Advanced Studies of the University of Luxembourg

Nina Buntic; Jochen Schneider; Marc Schlesser; André Schulz

Shared Underlying Mechanisms of Long-COvid and Chronic Fatigue Syndrome – A psychoneuroendocrinological and psychoimmunological perspective (SUMCO) – funded by the Institute for Advanced Studies, University of Luxembourg. At least 10 % of patients recovering from Covid-19 develop persistent health consequences such as fatigue, myalgia, or post-exertional malaise. “Long-Covid” is one of the many terms used to describe the occurrence of respiratory, cardiovascular, neurological, and/or gastrointestinal symptoms weeks after the initial infection is resolved. Although some symptoms seem to be unique to Long-Covid (e.g., olfactory & gustatory dysfunction), there is a large symptom overlap with the condition of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). ME/CFS is a complex, multisystem condition affecting 0.89 % of the global population. Different factors have been hypothesized to be involved in the aetiology of ME/CFS, including immune system dysregulation, metabolic alteration, autonomic nervous system (ANS) and limbic system dysfunction, as well as abnormalities in the hypothalamic-pituitary-adrenal (HPA) axis. One popular hypothesis postulates that ME/CFS is a post-infectious fatigue syndrome, as up to 50 % of ME/CFS cases develop after a viral infection (e.g., infection with Epstein-Barr Virus/EBV). This observation raises the question if Long-Covid and ME/CFS share similarities in underlying pathophysiology, as both conditions seem to occur after viral infections (SARS-CoV-2 & EBV), which trigger dysregulations in the immune system, the ANS, or the HPA axis. A proper characterization of Long-Covid and ME/CFS by a thorough, interdisciplinary psychological and physiological assessment may help to make a differential diagnostic distinction of the two patient groups. The aims of the current project are: (1) To reveal similarities and differences in the pathophysiology of Long-Covid and ME/CFS, as an in-depth understanding of the underlying psychobiology is essential to design adequate prevention in terms of early detection of pathological biomarkers and treatment interventions for Long-Covid syndromes and ME/CFS in terms of a graded exercise therapy. We specifically focus on potential alterations in the immune system, the ANS, and the HPA axis. (2) We aim to elucidate how these processes translate into severity of fatigue, as the relationship between these alterations and actual symptom distress remains yet unclear. Ultimately, as biological and psychological markers of Long-Covid and ME/CFS can help to monitor the course of symptoms and the potential responsiveness to treatment intervention, we aim (3) at investigating the effectiveness of a graded exercise therapy on symptom severity and potential improvement in alterations of the immune system, the ANS and the HPA axis.

https://www.uni.lu/fr/news/focus-on-young-researchers-at-the-ias-community-event/

01/07/2015

36

Research Support Department of the University of Luxembourg

Angelika Dierolf; Claus Vögele; André Schulz

Medically unexplained symptoms (MUS) are highly prevalent in Western societies, with a substantial proportion accounting for visits to physicians and often resulting in multiple, invasive diagnostic procedures. Yet, there is a dearth of evidence on the processes underlying the aetiology of MUS, in particular MUS-associated psychobiological mechanisms. The perception-filter-model posits that the perception of MUS are a result of the interplay between (a) increased bodily signals, and (b) filter processes, e.g., due to selective attention or health anxiety. Existing studies investigating interoceptive signal processing in MUS have focused on heartbeat perception tasks. This methodology has, however, important shortcomings: it relies on subjective reports and cannot, therefore, differentiate between actual bodily signals and the perception of these signals. In contrast to conventional heartbeat perception tasks, there are at least two methods available to assess the central representation of afferent cardiac signals independent of their perception: First, cardiac modulation of startle (CMS) is considered to reflect cardiac interoceptive signals at the level of the brainstem. Second, heartbeat-evoked potentials (HEPs) are interpreted as indicators for cardiac interoceptive signal processing at cortical level. Previous research has demonstrated the modulating effect of stress on interoception. Although MUS may be associated with dysregulations in physiological stress axes, as yet there are no studies investigating the relationship between interoceptive signal processing and physiological stress markers in MUS. Thus, the objectives of the current project are: (a) to clarify whether the central representation of afferent bodily signals is altered in MUS, (b) to elucidate possible associations of interoceptive signal processing with physiological stress indicators at rest and in response to an acute stressor, and (c) to investigate whether relationship between bodily signals, filter processes and MUS severity as postulated by the perception-filter model can be supported by empirical data.