Sibylle Petersen

Symptoms and the body: Taking the inferential leap

HighlightsThe experience of physical symptoms is related to physiological dysfunction in a highly variable way.Using a predictive coding framework we propose a new model of the body‐symptom relationship.We describe critical conditions influencing the body‐symptom correspondence.Theoretical and clinical implications of this new account are explored. ABSTRACT The relationship between the conscious experience of physical symptoms and indicators of objective physiological dysfunction is highly variable and depends on characteristics of the person, the context and their interaction. This relationship often breaks down entirely in the case of “medically unexplained” or functional somatic symptoms, violating the basic assumption in medicine that physical symptoms have physiological causes. In this paper, we describe the prevailing theoretical approach to this problem and review the evidence pertaining to it. We then use the framework of predictive coding to propose a new and more comprehensive model of the body‐symptom relationship that integrates existing concepts within a unifying framework that addresses many of the shortcomings of current theory. We describe the conditions under which a close correspondence between the experience of symptoms and objective physiology might be expected, and when they are likely to diverge. We conclude by exploring some theoretical and clinical implications of this new account.

Illness and symptom perception: a theoretical approach towards an integrative measurement model.

Several models have been proposed to conceptualize psychological representations of health, illness, and bodily sensations. These models differ as to the cognitive and affective components they include, whether they study the interaction of these components, and whether associations between psychological representations of bodily states and affective and behavioral reactions to these representations are considered conditional. These different conceptualizations and corresponding measurement approaches exist in parallel without resulting in synergistic effects or theoretical advancements within the field. In this paper, we review theoretical models on perception and attitudes and construct an integrative theoretical framework on psychological representation of bodily symptoms as well as more abstract representations of health and disease. The aim of this combination of approaches is to unify the strengths of different research domains in the conceptualization and measurement of mental representations of bodily states. Furthermore, the aim is to specify new, testable predictions and implications about the (conditional) relationship of these mental representations and affective and behavioral consequences. A core element in this integrative model is comparison. We review how comparison processes can change the cognitive and affective reference frame for illness and symptom perception and in turn affective and behavioral reactions. We discuss implications for measurement of illness and symptom representations as well as implications for clinical practice. Finally, we make suggestions for a research agenda to validate the proposed model as well as to address new questions derived from it.

Categorical Interoception Perceptual Organization of Sensations From Inside

Adequate perception of bodily sensations is essential to protect health. However, misinterpretation of signals from within the body is common and can be fatal, for example, in asthma or cardiovascular disease. We suggest that placing interoceptive stimuli into interoceptive categories (e.g., the category of symptoms vs. the category of benign sensations) leads to perceptual generalization effects that may underlie misinterpretation. In two studies, we presented stimuli inducing respiratory effort (respiratory loads) either organized into categories or located on a continuous dimension. We found pervasive effects of categorization on magnitude estimations, affective stimulus evaluations, stimulus recognition, and breathing behavior. These findings indicate the need for broadening perspectives on interoception to include basal processes of stimulus organization, in order for interoceptive bias to be understood. The results are relevant to a wide range of interoception-related phenomena, from emotion to symptom perception.

Awareness of Breathing: The Structure of Language Descriptors of Respiratory Sensations

OBJECTIVE Recent research suggests that dyspnea is not a single sensation but a multidimensional construct reflected in different verbal descriptors that can provide useful diagnostic information. In this study superordinated clusters of dyspnea were investigated in combination with a dimensional approach. DESIGN We examined the use of 20 respiratory symptom descriptors by healthy volunteers who completed a protocol of seven experimental conditions: Quiet breathing, breath holding, paced breathing, climbing stairs, resistive load breathing, voluntary hyperinflation, and voluntary hyperventilation. MAIN OUTCOME MEASURES We analyzed the ratings of these descriptors with multidimensional scaling (MDS) and cluster analysis. RESULTS AND CONCLUSION While similarities with prior studies were found on a lower fusion level, we were able to demonstrate the usefulness of interpreting higher fusion levels with four clusters related to work of breathing, coordination, suffocation, and struggling for air, merging into two superordinated clusters, effort and air hunger that are compatible with widely accepted primary components of dyspnea. MDS results also suggested that future studies should consider further breathing sensations related to cognitive control of breathing.

An Integrative Theoretical Model for Improving Resident-City Identification

Research from social and environmental psychology has shown that identification by residents with a place leads to numerous desirable outcomes like increased commitment and residential satisfaction. Thus, in the competition for residents, cities focus on building a favorable identity of a place to increase identification with the place. However, little is known regarding the predictors of resident-city identification and their link to desirable outcomes. We thus present an interdisciplinary model which outlines determinants and outcomes of identification and which integrates theories from geography, psychology, and organizational science to introduce a new theoretical perspective to the field of urban research. We propose that a strong resident-city identification results from a fit between the city prototype and the residents self-concept. In this relationship, perceived place complexity is a central variable. We develop research propositions and suggest an agenda for testing the model empirically. Finally, we discuss how increasing resident-city identification by using a more complex communication can benefit both the city and its inhabitants.

Interoception and symptom reporting: disentangling accuracy and bias

Anxiety and anxiety sensitivity are positively related to accuracy in the perception of bodily sensations. At the same time, research consistently reports that these traits are positively related to bias, resulting in the report of more and more intense symptoms that poorly correspond with physiological dysfunction. The aim of this study was to test the relationship of accuracy and bias in interoception. Furthermore, we tested the impact of individual differences in negative affect and symptom report in daily life on interoceptive accuracy and bias. Individuals higher in symptom report in daily life and negative affect were marginally more accurate in an interoceptive classification task in which participants were asked to identify different respiratory stimuli (inducing breathing effort) as belonging to a high or low intensity category. At the same time, bias in overestimating intensity of stimuli was significantly increased in participants higher in symptom report and negative affect, but only for more ambiguous stimuli. Results illustrate that interoceptive accuracy and bias need to be considered independently to understand their interaction with psychological factors and to disentangle (mis)perception of bodily sensations from liberal or conservative perceptual decision strategies.

Respiratory muscle tension as symptom generator in individuals with high anxiety sensitivity.

Objective Anxiety and panic are associated with the experience of a range of bodily symptoms, in particular unpleasant breathing sensations (dyspnea). Respiratory theories of panic disorder have focused on disturbances in blood gas regulation, but respiratory muscle tension as a source of dyspnea has not been considered. We therefore examined the potential of intercostal muscle tension to elicit dyspnea in individuals with high anxiety sensitivity, a risk factor for developing panic disorder. Methods Individuals high and low in anxiety sensitivity (total N = 62) completed four tasks: electromyogram biofeedback for tensing intercostal muscle, electromyogram biofeedback for tensing leg muscles, paced breathing at three different speeds, and a fine motor task. Global dyspnea, individual respiratory sensations, nonrespiratory sensations, and discomfort were assessed after each task, whereas respiratory pattern (respiratory inductance plethysmography) and end-tidal carbon dioxide (capnography) were measured continuously. Results In individuals with high compared to low anxiety sensitivity, intercostal muscle tension elicited a particularly strong report of obstruction (M = 5.1, SD = 3.6 versus M = 2.5, SD = 3.0), air hunger (M = 1.9, SD = 2.1 versus M = 0.4, SD = 0.8), hyperventilation symptoms (M = 0.6, SD = 0.6 versus M = 0.1, SD = 0.1), and discomfort (M = 5.1, SD = 3.2 versus M = 2.2, SD = 2.1) (all p values <.05). This effect was not explained by site-unspecific muscle tension, voluntary manipulation of respiration, or sustained task-related attention. Nonrespiratory control sensations were not significantly affected by tasks (F < 1), and respiratory variables did not reflect any specific responding of high–Anxiety Sensitivity Index participants to intercostal muscle tension. Conclusions Respiratory muscle tension may contribute to the respiratory sensations experienced by panic-prone individuals. Theories and treatments for panic disorder should consider this potential source of symptoms.

Idiopathic Environmental Intolerance: A comprehensive model

Idiopathic environmental intolerance refers to a group of poorly understood health conditions characterized by heterogeneous somatic symptoms that occur in response to environmental triggers, but for which no physiological causes can be found. We focus on three varieties, namely symptoms attributed to (a) chemical substances, (b) electromagnetic fields, and (c) infrasound and vibroacoustic sources. As no clear link with organ pathology or dysfunction has been established so far, we review critical evidence about alternative causal mechanisms as a platform for a novel unifying model of these conditions. There is consistent evidence that expectancy and nocebo mechanisms are critically involved. Using recent predictive coding models of brain functioning, we describe a comprehensive new model to explain how symptoms come about and become linked to specific environmental cues. This new model integrates phenomenally different pathologies, suggests testable new hypotheses, and specifies implications for treatment.

Social comparison and anxious mood in pulmonary rehabilitation: the role of cognitive focus.

OBJECTIVES   Comorbid anxiety is highly prevalent in Chronic Obstructive Pulmonary Disease (COPD), and it is related to increased morbidity and mortality. It has consistently been found that social comparison has substantial impact on mood. However, despite the strong social component of pulmonary rehabilitation, the effect of social comparison processes on anxiety has not been explored in this context. DESIGN   Participants were 43 COPD patients enrolled in a 3-week pulmonary rehabilitation programme. We tested in a longitudinal design the relationship between social comparison and assimilation and contrast at the beginning of rehabilitation and anxious mood at the end of the programme. METHODS   Using moderator analysis, we tested whether perceived similarities and differences to upward and downward social comparison standards influence the relationship between comparison direction at the beginning of the programme and anxious mood at the end of the programme. RESULTS   The relationship between social comparison at the start of rehabilitation and anxious mood at the end of the programme was dependent on assimilation and contrast to upward and downward standards. Downward assimilation and upward contrast were related to a stronger relationship of upward and downward social comparison and anxious mood. CONCLUSION   This study demonstrates the important role of social comparison focus in moderating beneficial effects of pulmonary rehabilitation. Downward assimilation and upward contrast might be important targets in reducing anxiety in pulmonary rehabilitation.

Geriatric dyspnea: Doing worse, feeling better

Older age is associated with a decline in physical fitness and reduced efficiency of the respiratory system. Paradoxically, it is also related to reduced report of dyspnea, that is, the experience of difficult and uncomfortable breathing. Reduced symptom reporting contributes to misdiagnosis or late diagnosis of underlying disease, suboptimal treatment, faster disease progression, shorter life expectancy, lower quality of life for patients, and considerably increased costs for the health care system in an aging society. However, pathways in the complex relationship between dyspnea and age are not well explored yet. We propose a model on geriatric dyspnea that integrates physiological, neurological, psychological and social pathways which link older age with dyspnea perception and expression. We suggest that the seemingly paradox of reduction of dyspnea in older age, despite physiological decline, can be solved by taking age-related changes on these multiple levels into account. In identifying these variables, the Geriatric Dyspnea Model highlights risk factors for reduced dyspnea perception and report in older age and pathways for intervention.