Descriptive and predictive validity of somatic attributions in patients with somatoform disorders: a systematic review of quantitative research

Respiratory Interoception and Pathological Illness Anxiety: Disentangling Bias

OBJECTIVE

Biased interoception decoupled from physiology might be relevant in the etiology of pathological illness anxiety (PIA). Empirical evidence for interoceptive deviations in illness anxiety is scarce but potentially informative to optimize treatments. We hypothesized that persons with PIA differ fundamentally in the classification of bodily sensations from those without PIA.

METHODS

In a respiratory categorization task, participants breathed into a pulmonary training device. Inspiration effort was varied by eight resistive loads. The lower/higher four loads were introduced as belonging to arbitrary categories "A"/"B," respectively. Participants memorized respiratory sensations in a first experimental block and were asked to label the resistances in a second block. We calculated the sensitivity of resistance classification according to category and response bias in terms of categorical misclassification. Data of 39 participants with PIA and 35 controls were compared with regard to sensitivity and response bias by group, resistive load, and their interaction in a multiple regression.

RESULTS

With similar sensitivity, patients more often labeled loads above the categorical border erroneously as belonging to category A, thus underestimating their resistance ( β = -0.06, p = .001; η2 = 0.02).

CONCLUSIONS

Individuals with PIA showed a systematic "wait and see" approach. Altered respiroception in PIA might stem from biased perception during training phase, the recognition phase, biased memory, or a combination of these. Its exact characteristics remain unknown, and future research must address the challenge of developing reliable and valid paradigms accounting for the variability of interoceptive biases.

REGISTRATION

This work was preregistered on OSF ( https://osf.io/9shcw ).

Reattribution to Mind-Brain Processes and Recovery From Chronic Back Pain: A Secondary Analysis of a Randomized Clinical Trial

Importance

In primary chronic back pain (CBP), the belief that pain indicates tissue damage is both inaccurate and unhelpful. Reattributing pain to mind or brain processes may support recovery.

Objectives

To test whether the reattribution of pain to mind or brain processes was associated with pain relief in pain reprocessing therapy (PRT) and to validate natural language-based tools for measuring patients' symptom attributions.

Design, Setting, and Participants

This secondary analysis of clinical trial data analyzed natural language data from patients with primary CBP randomized to PRT, placebo injection control, or usual care control groups and treated in a US university research setting. Eligible participants were adults aged 21 to 70 years with CBP recruited from the community. Enrollment extended from 2017 to 2018, with the current analyses conducted from 2020 to 2022.

Interventions

PRT included cognitive, behavioral, and somatic techniques to support reattributing pain to nondangerous, reversible mind or brain causes. Subcutaneous placebo injection and usual care were hypothesized not to affect pain attributions.

Main Outcomes and Measures

At pretreatment and posttreatment, participants listed their top 3 perceived causes of pain in their own words (eg, football injury, bad posture, stress); pain intensity was measured as last-week average pain (0 to 10 rating, with 0 indicating no pain and 10 indicating greatest pain). The number of attributions categorized by masked coders as reflecting mind or brain processes were summed to yield mind-brain attribution scores (range, 0-3). An automated scoring algorithm was developed and benchmarked against human coder-derived scores. A data-driven natural language processing (NLP) algorithm identified the dimensional structure of pain attributions.

Results

We enrolled 151 adults (81 female [54%], 134 White [89%], mean [SD] age, 41.1 [15.6] years) reporting moderate severity CBP (mean [SD] intensity, 4.10 [1.26]; mean [SD] duration, 10.0 [8.9] years). At pretreatment, 41 attributions (10%) were categorized as mind- or brain-related across intervention conditions. PRT led to significant increases in mind- or brain-related attributions, with 71 posttreatment attributions (51%) in the PRT condition categorized as mind- or brain-related, as compared with 22 (8%) in control conditions (mind-brain attribution scores: PRT vs placebo, g = 1.95 [95% CI, 1.45-2.47]; PRT vs usual care, g = 2.06 [95% CI, 1.57-2.60]). Consistent with hypothesized PRT mechanisms, increases in mind-brain attribution score were associated with reductions in pain intensity at posttreatment (standardized β = -0.25; t127 = -2.06; P = .04) and mediated the effects of PRT vs control on 1-year follow-up pain intensity (β = -0.35 [95% CI, -0.07 to -0.63]; P = .05). The automated word-counting algorithm and human coder-derived scores achieved moderate and substantial agreement at pretreatment and posttreatment (Cohen κ = 0.42 and 0.68, respectively). The data-driven NLP algorithm identified a principal dimension of mind and brain vs biomechanical attributions, converging with hypothesis-driven analyses.

Conclusions and Relevance

In this secondary analysis of a randomized trial, PRT increased attribution of primary CBP to mind- or brain-related causes. Increased mind-brain attribution was associated with reductions in pain intensity.

Intrinsic functional brain connectivity patterns underlying enhanced interoceptive sensibility

BACKGROUND

Cumulative evidence has suggested that brain regions including the bilateral insula and the anterior cingulate cortex play critical roles in the processing of interoceptive information. However, the brain functional connectivity patterns underlying interoceptive sensibility (IS) and their role in the relationship between IS and self-reported bodily symptoms remain unknown. We aimed to investigate the intrinsic functional connectivity patterns associated with IS and how this modulates the relationship between IS and self-reported bodily symptoms.

METHODS

Resting-state functional magnetic resonance imaging was used to test the intrinsic large-scale functional connectivity in 459 healthy subjects. IS and self-reported bodily symptoms were assessed by questionnaires.

RESULTS

Individuals with greater IS had a stronger tendency to report bodily symptoms. Higher IS was correlated with decreased ventral anterior insula-superior temporal gyrus, dorsal anterior cingulate cortex-middle frontal cortex and amygdala-medioventral occipital cortex connectivity. The large-scale functional connectivity of cingulo-opercular task control network (CON)-default mode network, CON-subcortical network and CON-dorsal attention network moderated the association between IS and bodily symptoms.

LIMITATIONS

The Body Perception Questionnaire mainly reflects the self-perceived tendency to focus on negatively-valenced interoceptive sensations. Future research should distinguish neutral and negative IS in order to make the definition of IS clearer.

CONCLUSIONS

This study suggests that IS may be related to impaired intrinsic functional connectivity between brain areas related to multisensory integration and cognitive-affective control, resulting in increased vigilance-attention to bodily signals. These findings offer new empirical evidence for a better understanding of the intricate relationships between interoception and symptom reporting.

Functional Stroke Symptoms: A Narrative Review and Conceptual Model

Stroke services have been reconfigured in recent years to facilitate early intervention. Throughout stroke settings, some patients present with functional symptoms that cannot be attributed to a structural cause. Emphasis on fast diagnosis and treatment means that a proportion of patients entering the care pathway present with functional symptoms that mimic stroke or have functional symptoms in addition to vascular stroke. There is limited understanding of mechanisms underlying functional stroke symptoms, how the treatment of such patients should be managed, and no referral pathway or treatment. Predisposing factors vary between individuals, and symptoms are heterogeneous: onset can be acute or insidious, and duration can be short-lived or chronic in the context of new or recurrent illness cognitions and behaviors. This article proposes a conceptual model of functional symptoms identified in stroke services and some hypotheses based on a narrative review of the functional neurological disorder literature. Predisposing factors may include illness experiences, stressors, and chronic autonomic nervous system arousal. Following the onset of distressing symptoms, perpetuating factors may include implicit cognitive processes, classical and operant conditioning, illness beliefs, and behavioral responses, which could form the basis of treatment targets. The proposed model will inform the development of theory-based interventions as well as a functional stroke care pathway.

Understanding persistent physical symptoms: Conceptual integration of psychological expectation models and predictive processing accounts

Persistent physical symptoms (PPS) are distressing, difficult to treat, and pose a major challenge to health care providers and systems. In this article, we review two disparate bodies of literature on PPS to provide a novel integrative model of this elusive condition. First, we draw on the clinical-psychological literature on the role of expectations to suggest that people with PPS develop dysfunctional expectations about health and disease that become increasingly immune to disconfirmatory information (such as medical reassurance) through cognitive reappraisal. Second, we invoke neuroscientific predictive processing accounts and propose that the psychological process of 'cognitive immunization' against disconfirmatory evidence corresponds, at the neurobiological and computational level, to too much confidence (i.e. precision) afforded to prior predictions. This can lead to an attenuation of disconfirming sensory information so that strong priors override benign bodily signals and make people believe that something serious is wrong with the body. Combining these distinct accounts provides a unifying framework for persistent physical symptoms and shifts the focus away from their causes to the sustaining mechanisms that prevent symptoms from subsiding spontaneously. Based on this integrative model, we derive new avenues for future research and discuss implications for treating people with PPS in clinical practice.

Symptoms and the body: Taking the inferential leap

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.

A concept mapping study on perpetuating factors of functional somatic symptoms from clinicians' perspective

OBJECTIVE

The aim of this concept mapping study was to identify the structure and alleged importance of perpetuating factors of functional somatic symptoms (FSS) from the perspective of professionals. Further, we examined to which extent these factors have been addressed in scientific literature.

METHODS

Ninety-nine perpetuating factors were sorted with respect to content using a card-sorting task by 61 experienced clinicians (62.3% psychologists, 75.4% female, mean age: 45.7 [SD: 10.6] years, mean duration of experience in treating FSS patients: 10.5 [SD: 7.6] years). These factors had been derived from in-depth interviews with 12 clinicians, with extensive experience in treating FSS. Thirty-eight clinicians rated the importance of the 99 factors on a scale ranging from 1 ('not important at all') to 10 ('extremely important').

RESULTS

Hierarchical cluster analysis revealed three overarching domains of perpetuating factors: 'Hypochondria', 'Social and relational problems' and 'Symptom-related emotions and habits'. These domains comprised 16 clusters, which were rated on importance between 6.1, 'Adverse physical factors and counterproductive lifestyle', and 7.8, 'Frustration and despair regarding the symptoms'. All clusters have been addressed in scientific literature.

CONCLUSIONS

This study revealed an encompassing hierarchical structure of somatic, emotional, cognitive, behavioral, and social factors of importance in the perpetuation of FSS based on expert opinions. This structure will guide the development of personalized treatment of FSS.