Understanding Babinski's anosognosia : 100 years later

Non peer reviewedFinal Accepted Versio

The virtual bodily self: Mentalisation of the body as revealed in anosognosia for hemiplegia

AbstractDespite the coherence and seeming directness of our bodily experience, our perception of the world, including that of our own body, may constitute an inference based on ambiguous sensory data and prior expectations. In this article, I apply a ‘psychologised’ version of the recently proposed free energy framework to the understanding of certain disorders of neurological unawareness in order to examine how inferential processes may determine our body perception. I specifically consider three facets of body perception in such disorders: namely, the ‘external body’ as inferred on the basis of exteroceptive signals and related predictions; the ‘internal body’ as inferred on the basis of proprioceptive and interoceptive signals and related predictions; and lastly the ‘impersonalised body’ as inferred on the basis of signals from social and third-person perspectives on the body and related predictions. Several conclusions will be drawn from these considerations: (a) there is a deep interdependency of prior beliefs and sensory data; as the brain uses sensory data to update its virtual model of the world, lack or imprecision of sensory prediction errors may lead to aberrant inferences influenced disproportionally by outdated, premorbid predictions; (b) interoception and interoceptive salience have a unique role in our inferences about body awareness and (c) social, ‘objectified’ prior beliefs about the body may have a silent but potent role in our bodily self-awareness. Finally, the article emphasizes that our learned, virtual model of the body is depended on the nature and thus integrity of the very body that allowed the model to be formed in the first place

Confabulation: Constructing motivated memories

Neurological confabulation is a prototypical form of false remembering and as such, it can provide insight into the nature of human memory. The main aims of the thesis was to empirically investigate the neuropsychological hypothesis that the content of confabulation is motivated. This was addressed by studying the neuropathological and neuropsychological profiles of 13 neurological patients with severe forms of confabulation, and by conducting three original experimental group studies and two single-case studies. Confabulating patients were compared with frontal and amnesic non-confabulating patients, as well as with neurologically healthy controls. Neuropathological findings confirmed previous indications of orbital and medial prefrontal cortex (OMPFC) damage or disconnection. Neuropsychological data showed that the presence of amnesia and executive function varied across confabulating patients. The first experimental study revealed that bilateral confabulating patients showed a positive emotional bias in their spontaneous confabulations. The second study, based on a recognition experiment, confirmed the presence of this bias, over and above the deficits of temporality and reality monitoring. The third study was based on an emotional prose recall experiment, in which the self- relevance of the material was manipulated. This revealed that the emotional biases shown by confabulating patients were self-serving, and not explicable by deficits of amnesia or executive dysfunction. These self-serving biases were common to bilateral and unilateral confabulating patients, but their confabulations showed valence differences. Two single-case studies provided further specification to these findings and showed that confabulating patients form confabulations according to the values and goals of their premorbid self-representation. In conclusion, this thesis provided experimental support for the hypothesis that the content of confabulation is motivated. This finding was conceptualised as a disinhibition of emotional memory associations, most likely caused by damage or functional disconnection of the OMPFC from adjacent limbic structures. These conclusions have wider implications about the role of the OMPFC in mediating the relation between emotion and memory

Definition: Asomatognosia

Peer reviewedFinal Accepted Versio

Why empathy has a beneficial impact on others in medicine: unifying theories

The past decades have seen an explosion of studies on empathy in various academic domains including affective neuroscience, psychology, medicine, and economics. However, the volumes of research have almost exclusively focused on its evolutionary origins, development, and neurobiological bases, as well as how the experience of empathy is modulated by social context and interpersonal relationships. In the present paper, we examine a much less attended side of empathy: why it has a positive impact on others? After specifying what the construct of empathy encompasses, we briefly review the various effects of empathy on health outcomes in the domain of medicine. We then propose two non-mutually exclusive mechanistic explanations that contribute to explain the positive effects of physician empathy on patients. (1) The social baseline theory (SBT), building on social support research, proposes that the presence of other people helps individuals to conserve metabolically costly somatic and neural resources through the social regulation of emotion. (2) The free energy principle (FEP) postulates that the brain optimizes a (free energy) bound on surprise or its complement value to respond to environmental changes adaptively. These conceptualizations can be combined to provide a unifying integrative account of the benefits of physicians' empathetic attitude on their patients and how it plays a role in healing beyond the mere effect of the therapeutic alliance

From the Fact to the Sense of Agency

This chapter reviews the empirical literature and contrast explicit and implicit tasks investigating the experience of agency with the aim of identifying the functional and neural signatures of the sense of agency. From the design of nonecological situations where there is ambiguity over the authorship of an action to the implementation of control conditions of passive movements that make little sense in our everyday waking life, the reviewed studies have tried to identify the key elements of what constitutes the sense of agency in humans. The exact interplay between conscious intentions and behavior, and the balance between predictive and postdictive processes remain controversial. However, the empirical investigation of the fact of agency, that is, the study of situations where people unambiguously produce voluntary actions, suggests that self-generated behavior changes the perception of one’s body and the external world by integrating temporal and spatial representations of movements and their effects on the world

Interoceptive Ingredients of Body Ownership: Affective Touch and Cardiac Awareness in the Rubber Hand Illusion

This document is the Accepted Manuscript version of the following article: Laura Crucianelli, Charlotte Krahe, Paul M. Jenkinson, Aikaterini (Katerina) Fotopoulou, 'Interoceptive Ingredients of Body Ownership: Affective Touch and Cardiac Awareness in the Rubber Hand Illusion', Cortex, first published online 1 May 2017, available at doi: https://doi.org/10.1016/j.cortex.2017.04.018. © 2017 Elsevier Ltd. All rights reserved.The sense of body ownership represents a fundamental aspect of bodily self-consciousness. Using multisensory integration paradigms, recent studies have shown that both exteroceptive and interoceptive information contribute to our sense of body ownership. Interoception refers to the physiological sense of the condition of the body, including afferent signals that originate inside the body and outside the body. However, it remains unclear whether individual sensitivity to interoceptive modalities is unitary or differs between modalities. It is also unclear whether the effect of interoceptive information on body ownership is caused by exteroceptive ‘visual capture’ of these modalities, or by bottom-up processing of interoceptive information. This study aimed to test these questions in two separate samples. In the first experiment (N = 76), we examined the relationship between two different interoceptive modalities, namely cardiac awareness based on a heartbeat counting task, and affective touch perception based on stimulation of a specialized C tactile (CT) afferent system. This is an interoceptive modality of affective and social significance. In a second experiment (N = 63), we explored whether ‘off-line’ trait interoceptive sensitivity based on a heartbeat counting task would modulate the extent to which CT affective touch influences the multisensory process during the rubber hand illusion (RHI). We found that affective touch enhanced the subjective experience of body ownership during the RHI. Nevertheless, interoceptive sensitivity, as measured by a heartbeat counting task, did not modulate this effect, nor did it relate to the perception of ownership or of CT-optimal affective touch more generally. By contrast, this trait measure of interoceptive sensitivity appeared most relevant when the multisensory context of interoception was ambiguous, suggesting that the perception of interoceptive signals and their effects on body ownership may depend on individual abilities to regulate the balance of interoception and exteroception in given contexts.Peer reviewedFinal Accepted Versio

The Erogenous Mirror: Intersubjective and Multisensory Maps of Sexual Arousal in Men and Women

Erogenous zones of the body are sexually arousing when touched. Previous investigations of erogenous zones were restricted to the effects of touch on one's own body. However, sexual interactions do not just involve being touched, but also involve touching a partner and mutually looking at each other's bodies. We take a novel interpersonal approach to characterize the self-reported intensity and distribution of erogenous zones in two modalities: touch and vision. A large internet sample of 613 participants (407 women) completed a questionnaire, where they rated intensity of sexual arousal related to different body parts, both on one's own body and on an imagined partner's body in response to being touched but also being looked at. We report the presence of a multimodal erogenous mirror between sexual partners, as we observed clear correspondences in topographic distributions of self-reported arousal between individuals' own bodies and their preferences for a partner's body, as well as between those elicited by imagined touch and vision. The erogenous body is therefore organized and represented in an interpersonal and multisensory way