The limits of agency in walking humans

An important principle of human ethics is that individuals are not responsible for actions performed when unconscious. Recent research found that the generation of an action and the building of a conscious experience of that action (agency) are distinct processes and crucial mechanisms for self-consciousness. Yet, previous agency studies have focussed on actions of a finger or hand. Here, we investigate how agents consciously monitor actions of the entire body in space during locomotion. This was motivated by previous work revealing that (1) a fundamental aspect of self-consciousness concerns a single and coherent representation of the entire spatially situated body and (2) clinical instances of human behaviour without consciousness occur in rare neurological conditions such as sleepwalking or epileptic nocturnal wandering. Merging techniques from virtual reality, full-body tracking, and cognitive science of conscious action monitoring, we report experimental data about consciousness during locomotion in healthy participants. We find that agents consciously monitor the location of their entire body and its locomotion only with low precision and report that while precision remains low it can be systematically modulated in several experimental conditions. This shows that conscious action monitoring in locomoting agents can be studied in a fine-grained manner. We argue that the study of the mechanisms of agency for a person's full body may help to refine our scientific criteria of self-hood and discuss sleepwalking and related conditions as alterations in neural systems encoding motor awareness in walking humans.

Seeing and identifying with a virtual body decreases pain perception

Olaf Blanke, Bigna Lenggenhager, Roland von Känel

Pain and the conscious mind (or the self) are experienced in our body. Both are intimately linked to the subjective quality of conscious experience. Here, we used virtual reality technology and visuo-tactile conflicts in healthy subjects to test whether experimentally induced changes of bodily self-consciousness (self-location; self-identification) lead to changes in pain perception. We found that visuo-tactile stroking of a virtual body but not of a control object led to increased pressure pain thresholds and self-location. This increase was not modulated by the synchrony of stroking as predicted based on earlier work. This differed for self-identification where we found as predicted that synchrony of stroking increased self-identification with the virtual body (but not a control object), and positively correlated with an increase in pain thresholds. We discuss the functional mechanisms of self-identification, self-location, and the visual perception of human bodies with respect to pain perception.

2011

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

Olaf Blanke, Sebastian Dieguez Falcon, Lukas Heydrich

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.

Elsevier2010

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

Embodied space in architecture, cognitive neuroscience, and virtual reality

Isabella Maria Pasqualini

EPFL2012