Illusory own body perceptions: case reports and relevance for bodily self-consciousness

Neurological disorders of body representation have for a long time suggested the importance of multisensory processing of bodily signals for self-consciousness. One such group of disorders--illusory own body perceptions affecting the entire body--has been proposed to be especially relevant in this respect, based on neurological data as well as philosophical considerations. This has recently been tested experimentally in healthy subjects showing that integration of multisensory bodily signals from the entire body with respect to the three aspects: self-location, first-person perspective, and self-identification [corrected], is crucial for bodily self-consciousness. Here we present clinical and neuroanatomical data of two neurological patients with paroxysmal disorders of full body representation in whom only one of these aspects, self-identification, was abnormal. We distinguish such disorders of global body representation from related but distinct disorders and discuss their relevance for the neurobiology of bodily self-consciousness.

Embodied space in architecture, cognitive neuroscience, and virtual reality

Isabella Maria Pasqualini

Recent findings in cognitive neuroscience enable improved understanding of embodiment and egocentric space in architecture. From a historical perspective the human body has been inferred as a reference in the debate of architectonic proportion. It was suggested that architectonic form moulds the subjective experience of the environment in contingency with skilful articulation of geometrical proportions in a three-dimensional construct. Modern science recalls several notions of how perception, thought and action are embodied. Embodiment and the sense of body ownership as such have been linked to multisensory and own-body processing, allowing for a relationship between aspects of the self to the conception of architectonic space and theory. Investigations about multisensory integration of architectonic space and its relation to own-body processing may therefore provide scientific insight to metaphorical and functional associations with the human bodily experience of architectonic space and its digital representation including perspective and immersive virtual reality. Attempts to sketch an interaction between architecture and cognitive neuroscience may bring about a design discipline based on multisensory own-body processing with permeable borders to contemporary science and technologies. This PhD thesis introduces digital space and cognitive neuroscience to the investigation of embodiment in architecture using techniques from immersive virtual reality and cognitive psychology. Here, three experimental studies using immersive virtual reality were based on the phenomenology of own-body perception introducing parameters from architecture. With such setups we tested whether bodily self-consciousness may be associated to architecture through a visuo-tactile conflict, and, whether changes in the architectonic space modulate bodily self-consciousness. Our results relate bodily self-consciousness with architecture specific perceptions, as well as bodily stability. Also, we observed perceptual changes related to visual perspective. We discuss such findings with regard to bodily feelings and perceived geometry through a critical confrontation with notions of embodiment in architecture.

EPFL2012

Transient Modulations of Neural Responses to Heartbeats Covary with Bodily Self-Consciousness

Javier Bello Ruiz, Fosco Bernasconi, Olaf Blanke, Hyeongdong Park, Christian Pfeiffer, Roy Salomon

Recent research has investigated self-consciousness associated with the multisensory processing of bodily signals (e.g., somatosensory, visual, vestibular signals), a notion referred to as bodily self-consciousness, and these studies have shown that the manipulation of bodily inputs induces changes in bodily self-consciousness such as self-identification. Another line of research has highlighted the importance of signals from the inside of the body (e.g., visceral signals) and proposed that neural representations of internal bodily signals underlie self-consciousness, which to date has been based on philosophical inquiry, clinical case studies, and behavioral studies. Here, we investigated the relationship of bodily self-consciousness with the neural processing of internal bodily signals. By combining electrical neuroimaging, analysis of peripheral physiological signals, and virtual reality technology in humans, we show that transient modulations of neural responses to heartbeats in the posterior cingulate cortex covary with changes in bodily self-consciousness induced by the full-body illusion. Additional analyses excluded that measured basic cardiorespiratory parameters or interoceptive sensitivity traits could account for this finding. These neurophysiological data link experimentally the cortical mapping of the internal body to self-consciousness.

Soc Neuroscience2016

Leg muscle vibration modulates bodily self-consciousness: integration of proprioceptive, visual, and tactile signals

Jane Aspell, Olaf Blanke, Estelle Palluel

Behavioral studies have used visuo-tactile conflicts between a participant's body and a visually presented fake or virtual body to investigate the importance of bodily perception for self-consciousness (bodily self-consciousness). Illusory self-identification with a fake body and changes in tactile processing--modulation of visuo-tactile cross-modal congruency effects (CCEs)--were reported in previous findings. Although proprioceptive signals are deemed important for bodily self-consciousness, their contribution to the representation of the full body has not been studied. Here we investigated whether and how self-identification and tactile processing (CCE magnitude) could be modified by altering proprioceptive signals with 80-Hz vibrations at the legs. Participants made elevation judgments of tactile cues (while ignoring nearby lights) during synchronous and asynchronous stroking of a seen fake body. We found that proprioceptive signals during vibrations altered the magnitude of self-identification and mislocalization of touch (CCE) in a synchrony-dependent fashion: we observed an increase of self-identification and CCE magnitude during asynchronous stroking. In a second control experiment we studied whether proprioceptive signals per se, or those from the lower limbs in particular, were essential for these changes. We applied vibrations at the upper limbs (which provide no information about the position of the participant's body in space) and in this case observed no modulation of bodily self-consciousness or tactile perception. These data link proprioceptive signals from the legs that are conveyed through the dorsal column-medial lemniscal pathway to bodily self-consciousness. We discuss their integration with bodily signals from vision and touch for full-body representations.

2011

Embodied space in architecture, cognitive neuroscience, and virtual reality

Isabella Maria Pasqualini

EPFL2012