Exteroceptive and Interoceptive Body-Self Awareness in Fibromyalgia Patients.

Fibromyalgia is a widespread chronic pain disease characterized by generalized musculoskeletal pain and fatigue. It substantially affects patients' relationship with their bodies and quality of life, but few studies have investigated the relationship between pain and body awareness in fibromyalgia. We examined exteroceptive and interoceptive aspects of body awareness in 30 women with fibromyalgia and 29 control participants. Exteroceptive body awareness was assessed by a body-scaled action-anticipation task in which participants estimated whether they could pass through apertures of different widths. Interoceptive sensitivity (IS) was assessed by a heartbeat detection task where participants counted their heartbeats during different time intervals. Interoceptive awareness was assessed by the Multidimensional Assessment of Interoceptive Awareness (MAIA). The "passability ratio" (the aperture size for a 50% positive response rate, divided by shoulder width), assessed by the body-scaled action-anticipation task, was higher for fibromyalgia participants, indicating disrupted exteroceptive awareness. Overestimating body size correlated positively with pain and its impact on functionality, but not with pain intensity. There was no difference in IS between groups. Fibromyalgia patients exhibited a higher tendency to note bodily sensations and decreased body confidence. In addition, the passability ratio and IS score correlated negatively across the whole sample, suggesting an inverse relationship between exteroceptive and interoceptive body awareness. There was a lower tendency to actively listen to the body for insight, with higher passability ratios across the whole sample. Based on our results and building on the fear-avoidance model, we outline a proposal that highlights possible interactions between exteroceptive and interoceptive body awareness and pain. Movement based contemplative practices that target sensory-motor integration and foster non-judgmental reconnection with bodily sensations are suggested to improve body confidence, functionality, and quality of life.

Bilateral Alternating Auditory Stimulations Facilitate Fear Extinction and Retrieval.

Disruption of fear conditioning, its extinction and its retrieval are at the core of posttraumatic stress disorder (PTSD). Such deficits, especially fear extinction delay, disappear after alternating bilateral stimulations (BLS) during eye movement desensitization and reprocessing (EMDR) therapy. An animal model of fear recovery, based on auditory cued fear conditioning and extinction learning, recently showed that BLS facilitate fear extinction and fear extinction retrieval. Our goal was to determine if these previous results found in animals can be reproduced in humans. Twenty-two healthy participants took part in a classical fear conditioning, extinction, and extinction recall paradigm. Behavioral responses (fear expectations) as well as psychophysiological measures (skin conductance responses, SCRs) were recorded. The results showed a significant fear expectation decrease during fear extinction with BLS. Additionally, SCR for fear extinction retrieval were significantly lower with BLS. Our results demonstrate the importance of BLS to reduce negative emotions, and provide a successful model to further explore the neural mechanisms underlying the sole BLS effect in the EMDR.

Psychometric properties of the multidimensional assessment of interoceptive awareness (MAIA) in a Chilean population.

The multidimensional assessment of interoceptive awareness (MAIA) is an instrument designed to assess interoceptive awareness. The aim of this study was to adapt the original MAIA scale to Spanish and to analyze its psychometric properties in a Chilean population. The MAIA was administered to 470 adults, aged 18-70 years, 76.6% women and 23.4% men, residents of the provinces of Valparaíso and Concepción, Chile. Exploratory factor analysis reduced the scale from 32 to 30 items. Confirmatory factor analysis supports a structure of eight interrelated factors (Noticing, Not-Distracting, Not-Worrying, Attention Regulation, Emotional Awareness, Self- Regulation, Body Listening, and Trusting), similar to the original scale (χ(2) (371) = 659.78, p = 0.0001; CFI = 0.92, TLI = 0.91, RMSEA = 0.056 and SRMR = 0.059). The Spanish version showed appropriate indicators of construct validity and reliability, with a Cronbach's α of 0.90 for the total scale, and values between 0.40 and 0.86 for the different subscales. Similar to previous studies, low reliability was observed in two of the eight scales (Not-Distracting and Not-Worrying), thus further revision of these subscales is suggested. The Spanish version of MAIA proved to be a valid and reliable tool to investigate interoceptive awareness in the Chilean population.

Exploring the subjective experience of the "rubber hand" illusion.

Despite the fact that the rubber hand illusion (RHI) is an experimental paradigm that has been widely used in the last 14 years to investigate different aspects of the sense of bodily self, very few studies have sought to investigate the subjective nature of the experience that the RHI evokes. The present study investigates the phenomenology of the RHI through a specific elicitation method. More particularly, this study aims at assessing whether the conditions usually used as control in the RHI have an impact in the sense of body ownership and at determining whether there are different stages in the emergence of the illusion. The results indicate that far from being "all or nothing," the illusion induced by the RHI protocol involves nuances in the type of perceptual changes that it creates. These perceptual changes affect not only the participants' perception of the rubber hand but also the perception of their real hand. In addition, perceptual effects may vary greatly between participants and, importantly, they evolve over time.

Dolor crónico y modificaciones de la conciencia corporal / Chronic pain and disturbances in body awareness

Este artículo aborda la relación entre el dolor crónico y la conciencia corporal. El dolor crónico se refiere a un conjunto de patologías que se caracterizan por la presencia constante de dolor, cuya intensidad y duración no pueden ser explicadas en términos de lesiones del sistema nervioso periférico. La falta de explicación en términos de daño periférico ha llevado a los investigadores a suponer que el sistema nervioso central desempeña un papel crucial en estos síndromes. En particular, se ha propuesto que la cronicidad del dolor causada posiblemente por una perturbación de los mecanismos involucrados en lo que podría llamar-se la conciencia corporal 'exteroceptiva'. En la primera parte de este artículo presento estudios que muestran una relación bidireccional entre el dolor crónico y la conciencia corporal exteroceptiva, así como la hipótesis que el este dolor resulta de la perturbación de los mecanismos subyacentes a este tipo de conciencia corporal. A continuación, presento algunos problemas que esta hipótesis no logra explicar, y considero la relación entre el dolor crónico y el sistema nervioso autónomo. Por último, considero esta última relación a la luz de la noción de conciencia corporal 'interoceptiva', y sugiero que la comprensión de los mecanismos que relacionan los aspectos exteroceptivos e interoceptivos de la conciencia corporal, podrían contribuir a la comprensión de la naturaleza y el desarrollo de dolor crónico.

This review article addresses the relationship between chronic pain and body awareness. Chronic pain refers to an ensemble of pain conditions whose common characteristic is the fact that peripheral lesions cannot explain the duration and intensity of the pain. The lack of explanation in terms of peripheral damage has led researchers to assume that the central nervous system plays a crucial role in these conditions. In particular, one suggestion about how such central factors might operate is by influencing patients’ body awareness. In the first part of this article I present evidence showing a bidirectional relationship between chronic pain and what might be called ‘ exteroceptive’ body awareness, as well as the related hypothesis that pain results from a disruption in the mechanisms underlying exteroceptive body awareness. Next, I discuss some issues that this hypothesis fails to explain, and I consider the relationship between chronic pain and the autonomic nervous system. Finally, I relate this latter relationship to the notion of ‘interoceptive’ body awareness, and explore the idea that understanding the mechanisms that relate exteroceptive and interoceptive aspects of body awareness might shed light on the nature and development of chronic pain.