What grounds my experience of my body as my own? The body that one experiences is always one’s own, but it does not follow that one always experiences it as one’s own. One might even feel that a body part does not belong to oneself despite feeling sensations in it, like in asomatognosia. The article aims at understanding the link between bodily sensations and the sense of ownership by investigating the role played by the body schema.

When do children become aware of themselves as differentiated and unique entity in the world? When and how do they become self-aware? Based on some recent empirical evidence, 5 levels of self-awareness are presented and discussed as they chronologically unfold from the moment of birth to approximately 4-5 years of age. A natural history of children's developing self-awareness is proposed as well as a model of adult self-awareness that is informed by the dynamic of early development. Adult self-awareness is viewed (...) as the dynamic flux between basic levels of consciousness that develop chronologically early in life. (shrink)

The abilities to attribute an action to its proper agent and to understand its meaning when it is produced by someone else are basic aspects of human social communication. Several psychiatric syndromes, such as schizophrenia, seem to lead to a dysfunction of the awareness of one’s own action as well as of recognition of actions performed by other. Such syndromes offer a framework for studying the determinants of agency, the ability to correctly attribute actions to their veridical source. Thirty normal (...) subjects and 30 schizophrenic patients with and without hallucinations and/or delusional experiences were required to execute simple finger and wrist movements, without direct visual control of their hand. The image of either their own hand or an alien hand executing the same or a different movement was presented on a TV-screen in real time. The task for the subjects was to discriminate whether the hand presented on the screen was their own or not. Hallucinating and deluded schizophrenic patients were more impaired in discriminating their own hand from the alien one than the non-hallucinating ones, and tended to misattribute the alien hand to themselves. Results are discussed according to a model of action control. A tentative description of the mechanisms leading to action consciousness is proposed. (shrink)

Although philosophical approaches to the self are diverse, several of them are relevant to cognitive science. First, the notion of a 'minimal self', a self devoid of temporal extension, is clarified by distinguishing between a sense of agency and a sense of ownership for action. To the extent that these senses are subject to failure in pathologies like schizophrenia, a neuropsychological model of schizophrenia may help to clarify the nature of the minimal self and its neurological underpinnings. Second, there is (...) good evidence to suggest that although certain aspects of the minimal self are primitive and embodied, other aspects may be accessed only in reflective consciousness. Employing a modified concept of the minimal self, it may be possible to construct a robotic form of non-conscious self-reference that depends on an interaction between the robotic body and its environment. In contrast to the minimal self, the narrative self involves continuity over time and is directly relevant to discussions of memory and personal identity. There is growing consensus among philosophers and cognitive scientists about the importance of narrative and its relation to episodic memory and left-hemisphere functions. There are, however, at least two different views of how the narrative self is structured. On one model it is nothing more than an abstract point. On a more extended view, proposed here, the self is a rich amalgam of narratives that allows for the equivocations, contradictions, and self-deceptions of personal life. Even in this case, however, neurocognitive models contribute to our understanding of how narrative identity is structured. (shrink)

Two studies investigated the development of infants' visual preferences for the human body shape. In Study 1, infants of 12,15 and 18 months were tested in a standard preferential looking experiment, in which they were shown paired line drawings of typical and scrambled bodies. Results indicated that the 18-month-olds had a reliable preference for the scrambled body shapes over typical body shapes, while the younger infants did not show differential responding. In Study 2, 12- and 18-month-olds were tested with the (...) same procedure, except that the typical and scrambled body stimuli were photographic images. The results of Study 2 again indicated that only the 18-month-olds had a reliable preference for the scrambled body shapes. This finding contrasts sharply with infants' precocious preferences for human faces, suggesting that infants' learning about human faces and human bodies follow different developmental trajectories. (C) 2002 Elsevier Science B.V. All rights reserved. (shrink)

Descartes' Discourse marks a watershed in European thought; in it, the author sets out in brief his radical new philosophy, which begins with a proof of the existence of the self (the famous "cogito ergo sum"). Next he deduces from it the existence and nature of God, and ends by offering a radical new account of the physical world and of human and animal nature. Written in everyday language and meant to be read by common people of the day, it (...) swept away all previous philosophical traditions. This new translation is an ideal introduction to Descartes for the general reader. It is accompanied by a substantial introductory essay from Renaissance scholar Ian Maclean that is designed to provide in-depth historical and philosophical context. The essay draws on Descartes' correspondence to examine what brought him to write his great work, and the impact it had on his contemporaries. A detailed section of notes explain Descartes' philosophical terminology and ideas, as well as historical references and allusions. Any reader can feel comfortable diving in to this classic work of Renaissance philosophical thought. (shrink)

We investigated how motor agency in the voluntary control of body movement influences body awareness. In the Rubber Hand Illusion , synchronous tactile stimulation of a rubber hand and the participant’s hand leads to a feeling of the rubber hand being incorporated in the participant’s own body. One quantifiable behavioural correlate of the illusion is an induced shift in the perceived location of the participant’s hand towards the rubber hand. Previous studies showed that the induced changes in body awareness are (...) local and fragmented: the proprioceptive drift is largely restricted to the stimulated finger. In the present study, we investigated whether active and passive movements, rather than tactile stimulation, would lead to similarly fragmented body awareness. Participants watched a projected image of their hand under three conditions: active finger movement, passive finger movement, and tactile stimulation. Visual feedback was either synchronous or asynchronous with respect to stimulation of the hand. A significant overall RHI, defined as greater drifts following synchronous than asynchronous stimulation, was found in all cases. However, the distribution of the RHI across stimulated and non-stimulated fingers depended on the kind of stimulation. Localised proprioceptive drifts, specific to the stimulated finger, were found for tactile and passive stimulation. Conversely, during active movement of a single digit, the proprioceptive drifts were not localised to that digit, but were spread across the whole hand. Whereas a purely proprioceptive sense of body-ownership is local and fragmented, the motor sense of agency integrates distinct body-parts into a coherent, unified awareness of the body. (shrink)

There is converging evidence from developmental and cognitive psychology, as well as from neuroscience, to suggest that the self is both special and social, and that self-other interaction is the driving force behind self-development. We review experimental findings which demonstrate that human infants are motivated for social interactions and suggest that the development of an awareness of other minds is rooted in the implicit notion that others are like the self. We then marshal evidence from functional neuroimaging explorations of the (...) neurophysiological substrate of shared representations between the self and others, using various ecological paradigms such as mentally representing one's own actions versus others' actions, watching the actions executed by others, imitating the others' actions versus being imitated by others. We suggest that within this shared neural network the inferior parietal cortex and the prefrontal cortex in the right hemisphere play a special role in the essential ability to distinguish the self from others, and in the way the self represents the other. Interestingly, the right hemisphere develops its functions earlier than the left. (shrink)

Neurological syndromes in which consciousness seems to malfunction, such as temporal lobe epilepsy, visual scotomas, Charles Bonnet syndrome, and synesthesia offer valuable clues about the normal functions of consciousness and ‘qualia’. An investigation into these syndromes reveals, we argue, that qualia are different from other brain states in that they possess three functional characteristics, which we state in the form of ‘three laws of qualia ’ based on a loose analogy with Newton’s three laws of classical mechanics. First, they are (...) irrevocable: I cannot simply decide to start seeing the sunset as green, or feel pain as if it were an itch; second, qualia do not always produce the same behaviour: given a set of qualia, we can choose from a potentially infinite set of possible behaviours to execute; and third, qualia endure in short-term memory, as opposed to non-conscious brain states involved in the on-line guidance of behaviour in real time. We suggest that qualia have evolved these and other attributes (e.g. they are ‘filled in’) because of their role in facilitating non-automatic, decision-based action. We also suggest that the apparent epistemic barrier to knowing what qualia another person is experiencing can be overcome simply by using a ‘bridge ’ of neurons; and we offer a hypothesis about the relation between qualia and one’s sense of self. (shrink)