Differential rooting response by neonates: evidence for an early sense of self

Multisensory decisions from self to world

Classic Bayesian models of perceptual inference describe how an ideal observer would integrate 'unisensory' measurements (multisensory integration) and attribute sensory signals to their origin(s) (causal inference). However, in the brain, sensory signals are always received in the context of a multisensory bodily state-namely, in combination with other senses. Moreover, sensory signals from both interoceptive sensing of one's own body and exteroceptive sensing of the world are highly interdependent and never occur in isolation. Thus, the observer must fundamentally determine whether each sensory observation is from an external (versus internal, self-generated) source to even be considered for integration. Critically, solving this primary causal inference problem requires knowledge of multisensory and sensorimotor dependencies. Thus, multisensory processing is needed to separate sensory signals. These multisensory processes enable us to simultaneously form a sense of self and form distinct perceptual decisions about the external world. In this opinion paper, we review and discuss the similarities and distinctions between multisensory decisions underlying the sense of self and those directed at acquiring information about the world. We call attention to the fact that heterogeneous multisensory processes take place all along the neural hierarchy (even in forming 'unisensory' observations) and argue that more integration of these aspects, in theory and experiment, is required to obtain a more comprehensive understanding of multisensory brain function. This article is part of the theme issue 'Decision and control processes in multisensory perception'.

An integrative perspective on the role of touch in the development of intersubjectivity

Touch concerns a fundamental component of sociality. In this review, we examine the hypothesis that somatomotor development constitutes a crucial psychophysiological element in the ontogeny of intersubjectivity. An interdisciplinary perspective is provided on how the communication channel of touch contributes to the sense of self and extends to the social self. During gestation, the transformation of random movements into organized sequences of actions with sensory consequences parallels the development of the brain's functional architecture. Brain subsystems shaped by the coordinated activity of somatomotor circuits to support these first body-environment interactions are the first brain functional arrangements to develop. We propose that tactile self-referring behaviour during gestation constitutes a prototypic mode of interpersonal exchange that supports the subsequent development of intersubjective exchange. The reviewed research suggests that touch constitutes a pivotal bodily experience that in early stages builds and later filters self-other interactions. This view is corroborated by the fact that aberrant social-affective touch experiences appear fundamentally associated with attachment anomalies, interpersonal trauma, and personality disorders. Given the centrality of touch for the development of intersubjectivity and for psychopathological conditions in the social domain, dedicated research is urged to elucidate the role of touch in the evolution of subjective self-other coding.

Influences of infants' and mothers' contingent vocal responsiveness on young infants' vocal social bids in the Still Face Task

Infants' social bids in the still face phase of the Still Face Task demonstrate their emerging sense of self agency as these behaviors happen in the absence of the partner's social overtures. The study examined the role of infants' contingent responsiveness to their mothers in social interactions on their social bidding to the mother when she becomes unresponsive. Social bids are non-distress vocalizations or smiles while looking at the unresponsive partner. Infants and their mothers longitudinally engaged in the Still Face Task when infants were one, two, and three months. At two months, infant non-distress vocalizations and smiles and contingent vocal and smiling responsiveness increased in the initial interactive phase and vocal and smile social bids increased in the still face phase. Infant contingent vocal responsiveness predicted infant vocal social bids but infant contingent smiling responsiveness did not predict infant smile social bids. Infant contingent vocal responsiveness was a stronger predictor than infant non-distress vocalizations per se of infant vocal social bids at two and three months. However, maternal contingent vocal responsiveness was the primary predictor of infant vocal social bids at these ages. Maternal contingent responsiveness to infant behavior allows infants to sense their agency in affecting their mothers' behavior. Yet infants are active participants, becoming contingently responsive to their mothers, which facilitates their awareness that they are effective agents in instigating social interaction, as demonstrated by social bids.

Stop touching your face! A systematic review of triggers, characteristics, regulatory functions and neuro-physiology of facial self touch

Spontaneous face touching (sFST) is an ubiquitous behavior that occurs in people of all ages and all sexes, up to 800 times a day. Despite their high frequency, they have rarely been considered as an independent phenomenon. Recently, sFST have sparked scientific interest since they contribute to self-infection with pathogens. This raises questions about trigger mechanisms and functions of sFST and whether they can be prevented. This systematic comprehensive review compiles relevant evidence on these issues. Facial self-touches seem to increase in frequency and duration in socially, emotionally as well as cognitively challenging situations. They have been associated with attention focus, working memory processes and emotion regulating functions as well as the development and maintenance of a sense of self and body. The dominance of face touch over other body parts is discussed in light of the proximity of hand-face cortical representations and the peculiarities of facial innervations. The results show that underlying psychological and neuro-physiological mechanisms of sFST are still poorly understood and that various basic questions remain unanswered.

Clinical pointers from developing self-awareness

Seven typical developmental steps are described as cardinal changes leading children from implicit embodied self-awareness at birth, self-consciousness by 2 years, and the adoption of an ethical stance toward others by the preschool years (3-5y). This development may be a useful benchmark for clinicians. In this review, some clinical pointers are outlined in relation to each developmental step, but with a particular focus on the testing of self-awareness in children with developmental disorders, including autism spectrum disorder, cerebral palsy, and intellectual disability. WHAT THIS PAPER ADDS: There are seven major steps in early self and social awareness. Clinical pointers related to each of the seven steps are provided.

Newborn crawling and rooting in response to maternal breast odor

A growing literature shows that perception and action are already tightly coupled in the newborn. The current study aimed to examine the nature of the coupling between olfactory stimuli from the mother and the newborn's crawling and rooting (exploratory movements of the head). To examine the coupling, the crawling and rooting behavior of 28 2-day-old newborns were studied while they were supported prone on a mobility device shaped like a mini skateboard, the Crawliskate®, their head positioned directly on top of a pad infused with either their mother's breast odor (Maternal) or the odor of water (Control). Video and 3D kinematic analyses of the number and types of limb movements and quantification of displacement across the surface revealed that newborns are significantly more efficient crawlers when they smell the maternal odor, moving greater distances although performing fewer locomotor movements. In addition, the newborns made significantly more head rooting movements in the presence of the maternal odor. These findings suggest that the circuitry underlying quadrupedal locomotion and exploratory movements of the head is already adaptable to olfactory information via higher brain processing. Moreover, the coupling between olfaction and the two action systems, locomotion and rooting, is already differentiated. As crawling enables the newborn to move toward the mother's breast immediately after birth and facilitates mother-infant interaction, the results of this study highlight the potential value of using maternal odors to stimulate mobility in infants at risk of motor delay and/or deprived of this odor when born prematurely.

Caring babies: Concern for others in distress during infancy

Concern for distressed others is a highly valued human capacity, but little is known about its early ontogeny. Theoretical accounts of empathy development have emphasized stages, but this has been called into question. This study sheds new light on four key issues: onset, consistency, development, and predictive power of early manifestations of concern for others. Three-month-old Israei infants (N = 165) were followed longitudinally at ages 6, 12, and 18 months, and their observed responses to others' distress were assessed. Concern for distressed others was seen early in the first year of life, long before previous theories assumed. Empathic concern was moderately consistent across both situation and age, from as early as 3 months. Concern for others grew only modestly with age, plateauing during the second year, whereas prosocial behavior increased rapidly during the second year. Early individual differences in concern for others predicted later prosocial behavior on behalf of distressed others. Findings underscore the early roots of caring, and appear to refute assumptions of prior stage theories of empathy development, by showing that concern for others develops much earlier and more gradually than previously assumed.

Development of body knowledge as measured by arm differentiation in infants: From global to local?

The ability to sense and use the body parts in an organized and differentiated manner is a precursor of body knowledge in infancy. To acquire this ability, the infant's brain might explore the perceptual consequences of its bodily actions. Undifferentiated body movements would gradually be replaced by more precise actions. Only a very few studies have tested this ‘global‐to‐local’ hypothesis, and none of them have so far been replicated. In this study, we assessed arm differentiation in 4‐, 6‐, and 8‐month‐old infants using a new contingency detection task in which infants have to detect a contingency between one of their arms’ activity and an audiovisual stimulus on a screen. We found that 4‐ to 8‐month‐old infants seem to be able to use their arms in a differentiated manner. However, surprisingly, we were not able to show a developmental trend in arm differentiation between 4 and 8 months of age.

Impaired Corollary Discharge in Psychosis and At-Risk States: Integrating Neurodevelopmental, Phenomenological, and Clinical Perspectives

The brain is increasingly viewed in contemporary neuroscience as a predictive machine; its products, such as movements and decisions, are indeed accompanied by predictions of outcomes at distinct levels of awareness. In this conceptual review, we focus on corollary discharge, a basic neurophysiological mechanism that is allegedly involved in sensory prediction and contributes to the distinction between self-generated and externally generated actions. Failures in corollary discharge have been hypothesized as potentially relevant for the progressive development of positive psychotic symptoms such as passivity delusions and auditory verbal hallucinations. We articulate this framework adopting three confocal lenses, namely, the neurodevelopmental, phenomenological, and clinical perspectives. Converging evidence from these research domains indicates a possible developmental cascade leading to increased lifetime risk of psychosis. That is, early childhood alterations of corollary discharge mechanisms, endophenotypically expressed in motor impairment, may concur with a progressive fading of the feeling of self-agency on one's own experiences. Combined with other age-dependent situational challenges occurring along development, this may progressively hamper the ontogenesis of the embodied self, thereby facilitating the emergence of anomalous subjective experiences such as self-disorders (a longitudinal index of schizophrenia spectrum vulnerability) and broadly conceived clinical high-risk states. Overall, this condition increases the risk of developing passivity symptoms, phenotypically expressed in a severity gradient ranging from intrusive thoughts to passivity delusions and auditory verbal hallucinations. Empirical and clinical implications of this framework, as well as future scenarios, are discussed.

Self-Unity as Ground Zero of Learning and Development

Contrary to the suggestion that we are born in a state of confusion and primordial state of a-dualism with the environment, infancy research of the past 40 years shows that from the outset, infants are objective perceivers guided by rich evolved survival values of approach and avoidance in relation to specific resources in the environment such as faces, food, or smell. This starting-state competence drives and organizes their behavior. Evidence-based ascription of self-unity at birth is discussed. Selected findings are presented suggesting that self-unity is a primordial human experience, the main organizer of behavior from the outset. Self-unity is the necessary ground zero enabling the rapid learning and development taking place early in human life.

Motor Impairment and Developmental Psychotic Risk: Connecting the Dots and Narrowing the Pathophysiological Gap

The motor system in its manifold articulations is receiving increasing clinical and research attention. This is because motor impairments constitute a central, expressive component of the mental state examination and a key transdiagnostic feature indexing disease severity. Furthermore, within the schizophrenia spectrum, the integration of neurophysiological, developmental, and phenomenological perspectives suggests that motor impairment is not simply a generic, extrinsic proxy of an altered neurodevelopment, but might be more intimately related to psychotic risk. Therefore, an increased understanding, conceptualization, and knowledge of such motor system and its anomalies could empower contemporary risk prediction and diagnostic procedures.

Are sensorimotor experiences the key for successful early intervention in infants with congenital brain lesion?

Living with a congenital brain lesion may have detrimental effects on the ability to do everyday activities, but contrary to acquired brain lesions, people and in particular children, with congenital brain lesions may have limited or no experience of how their bodies work. This absence of experience gives rise to challenges for habilitation of sensorimotor abilities and derived cognitive abilities. How can motor and cognitive abilities be achieved and trained in an individual with no experience of potential abilities? In this article, we aim to review the existing knowledge about the development of sensorimotor integration. Further, we will discuss this knowledge in the light of two neurocognitive theories: embodied cognition and predictive coding. Moreover, using developmental knowledge and theory in combination, we will argue that early sensorimotor development serves as a foundation for later cognitive development. Finally, we try to use these elements in a strategy to make interventions as early as possible, with the purpose of improving sensorimotor and cognitive abilities in children with congenital brain lesions.

Uncanny Mirroring: A Developmental Perspective on the Neurocognitive Origins of Self-Disorders in Schizophrenia

Varieties of anomalous subjective experiences, i.e. "basic self-disorders" (SDs), have been empirically demonstrated as core clinical features of schizophrenia spectrum disorders, predating full-blown psychotic symptoms. However, the clinical stage in which SDs emerge and their putative neurocognitive origins remain unsolved issues. Focusing on a prototypical anomalous mirror experience (i.e., a stable, trait-like subjective feeling of nonexisting while looking at oneself in the mirror) reported by an 11-year-old boy at familial high risk for schizophrenia and diagnosed as attenuated psychosis syndrome, we outline some possible developmental pathways leading to SDs. Such pathways are hypothesized in accordance with the documented early impairments in perceptual integration across distinct modalities in children at risk for schizophrenia spectrum disorders and to the specific features of mirror experience as provided by phenomenological and developmental psychology perspectives. We conclude that SDs could presumably have an early developmental origin, although children become progressively more aware of them. Although further hypothesis testing in clinical samples and longitudinal empirical investigation of at-risk children is badly needed, we propose that age-appropriate, phenomenologically oriented assessment of SDs could be useful for the early identification of psychotic risk.

A Naturalistic Observation of Spontaneous Touches to the Body and Environment in the First 2 Months of Life

Self-generated touches to the body or supporting surface are considered important contributors to the emergence of an early sense of the body and self in infancy. Both are critical for the formation of later goal-directed actions. Very few studies have examined in detail the development of these early spontaneous touches during the first months of life. In this study, we followed weekly four infants in two naturalistic 5-min sessions (baseline and toys-in-view) as they laid alert in supine from the age of 3 weeks until they acquired head control. We found that throughout the 2 months of observation, infants engaged in a high rate of touch and spent about 50% of the time moving their hands from one touch location to the next. On most sessions, they produced up to 200 body/surface contacts and touched as many as 18 different areas (mainly upper body and floor) both hands combined. When we did not consider the specific areas touched, the rates of touches were higher to the body than to the floor, but the duration of contacts and the most touched areas were higher for the supporting surface than for the body. Until the age of 9 weeks, we found no consistent differences in the rate of touch between head and trunk. Infants also did not display significant differences in their rate of touch between right and left hand or between conditions. However, we discovered that in the earlier weeks, infants engaged more often in what we called “complex touches.” Complex touches were touches performed across several body/floor areas in one continuous bout while the hand maintained contact with the body or floor. Single touches, in contrast, corresponded to one touch to one single body or floor area at a time. We suggest that infants are active explorers of their own body and peripersonal space from day 1 and that these early self-generated and deeply embodied sensorimotor experiences form the critical foundation from which future behaviors develop.

The rooting reflex as an infant feeding cue

Experts in infant health and development consider the rooting reflex a cue of a baby's hunger and recommend feeding the infant when this reflex occurs. However, the relation between rooting and infant feeding status has not been well established in the literature. In the current study, seven parents documented the occurrence of their newborns' rooting, crying, and a control reflex (palmar grasp) before, after, and between naturally occurring feedings. For all participants, rooting occurred during a greater percentage of reflex checks prior to feedings, whereas the palmar grasp occurred during a similar percentage of checks across these time periods. These results provide empirical support for the rooting reflex as a feeding cue. However, data for only one dyad suggested a high probability of the rooting reflex occurring without crying during prefeeding checks. Thus, our data do not provide evidence that feeding in response to the rooting reflex would preempt infant crying.

The Ontogeny of Human Self-Consciousness

Self-consciousness is an essential characteristic of what it means to be human and is arguably a unique adaptation of our species. Human self-consciousness is construed here as the propensity to perceive and be aware of oneself not only for oneself, but also through the evaluative eyes of other individuals. The origins and determinants of this characteristic remain wide-open questions. I propose a developmental account and suggest possible new directions in the investigation of genetic, brain, and cultural factors that play a role in the ontogeny of human self-conscious psychology.

Know Your Body Through Intrinsic Goals

The first “object” that newborn children play with is their own body. This activity allows them to autonomously form a sensorimotor map of their own body and a repertoire of actions supporting future cognitive and motor development. Here we propose the theoretical hypothesis, operationalized as a computational model, that this acquisition of body knowledge is not guided by random motor-babbling, but rather by autonomously generated goals formed on the basis of intrinsic motivations. Motor exploration leads the agent to discover and form representations of the possible sensory events it can cause with its own actions. When the agent realizes the possibility of improving the competence to re-activate those representations, it is intrinsically motivated to select and pursue them as goals. The model is based on four components: (1) a self-organizing neural network, modulated by competence-based intrinsic motivations, that acquires abstract representations of experienced sensory (touch) changes; (2) a selector that selects the goal to pursue, and the motor resources to train to pursue it, on the basis of competence improvement; (3) an echo-state neural network that controls and learns, through goal-accomplishment and competence, the agent's motor skills; (4) a predictor of the accomplishment of the selected goals generating the competence-based intrinsic motivation signals. The model is tested as the controller of a simulated simple planar robot composed of a torso and two kinematic 3-DoF 2D arms. The robot explores its body covered by touch sensors by moving its arms. The results, which might be used to guide future empirical experiments, show how the system converges to goals and motor skills allowing it to touch the different parts of own body and how the morphology of the body affects the formed goals. The convergence is strongly dependent on competence-based intrinsic motivations affecting not only skill learning and the selection of formed goals, but also the formation of the goal representations themselves.

The Development of Sensorimotor Intelligence in Infants

Infancy is the most dynamic part of human development. During this period, all basic sensorimotor and cognitive abilities are established. In this chapter, we will trace some of the important achievements of this development with a focus on how infants achieve predictive control of actions, i.e., how they come to coordinate their behavior with the ongoing events in the world without lagging behind. With the maturation of the brain, new possibilities that have profound effects on cognition open up. Some of them are core abilities, i.e., they function at birth or very early in development. Important examples are the structured perception of objects and surfaces and the control of arm movements. Closely after birth, infants move their arms to the vicinity of objects in front of them demonstrating that they have some control of their arms and indicating that they perceive objects as such. Another example is the rapid onset of smooth-pursuit eye movements during the second month of life and the emerging ability to predict when and where an occluded moving object will reappear. At 4months of age, out of sight is no longer of mind. The child's sensorimotor system is especially designed to facilitate the extraction of knowledge about the world including other people. In addition, the infant is endowed with motives that ensure that the innate predispositions are transformed into a system of knowledge for guiding actions predictively. By perceiving and acting on the world, infants develop their cognition and through developmental studies; we can learn more about these processes.

Self-defense: Deflecting Deflationary and Eliminativist Critiques of the Sense of Ownership

I defend a phenomenological account of the sense of ownership as part of a minimal sense of self from those critics who propose either a deflationary or eliminativist critique. Specifically, I block the deflationary critique by showing that in fact the phenomenological account is itself a deflationary account insofar as it takes the sense of ownership to be implicit or intrinsic to experience and bodily action. I address the eliminativist view by considering empirical evidence that supports the concept of pre-reflective self-awareness, which underpins the sense of ownership. Finally, I respond to claims that phenomenology does not offer a positive account of the sense of ownership by showing the role it plays in an enactivist (action-oriented) view of embodied cognition.

Interpersonal harm aversion as a necessary foundation for morality: A developmental neuroscience perspective

Growing evidence from developmental psychology and social neuroscience emphasizes the importance of third-party harm aversion for constructing morality. A sensitivity to interpersonal harm emerges very early in ontogeny, as reflected in both the capacity for implicit social evaluation and an aversion for antisocial agents. Yet it does not necessarily entail avoidance toward inflicting pain to others. Later, an understanding that harmful actions cause suffering emerges, followed by an integration of rules that can depend on social contexts and cultures. These developmental findings build on a burgeoning literature, which suggests that the fundamental nature of moral and social cognition, including their motivational and hedonic value, lies in general computational processes such as attention, approach-avoidance, social valuation, and decision making rather than in fully distinct, dedicated neural regions for morality. Bridging the gap between cognition and behaviors and the requisite affective, motivational, and cognitive mechanisms, a developmental neuroscience approach enriches our understanding of the emergence of morality.

The role of self-other distinction in understanding others' mental and emotional states: neurocognitive mechanisms in children and adults

Social interactions come with the fundamental problem of trying to understand others' mental and affective states while under the overpowering influence of one's own concurrent thoughts and feelings. The ability to distinguish between simultaneous representations of others' current experiences as well as our own is crucial to navigate our complex social environments successfully. The developmental building blocks of this ability and how this is given rise to by functional and structural brain development remains poorly understood. In this review, I outline some of the key findings on the role of self-other distinction in understanding others' mental as well as emotional states in children and adults. I will begin by clarifying the crucial role for self-other distinction in avoiding egocentric attributions of one's own cognitive as well as affective states to others in adults and outline the underlying neural circuitry in overcoming such egocentricity. This will provide the basis for a discussion of the emergence of self-other distinction in early childhood as well as developmental changes therein throughout childhood and into adulthood. I will demonstrate that self-other distinction of cognitive and emotional states is already dissociable early in development. Concomitantly, I will show that processes of self-other distinction in cognitive and affective domains rely on adjacent but distinct neural circuitry each with unique connectivity profiles, presumably related to the nature of the distinction that needs to be made.

Other-self confusions in action memory: The role of motor processes

People can come to falsely remember performing actions that they have not actually performed. Common accounts of such false action memories have invoked source confusion from the overlap of sensory features but largely ignored the role of motor processes. We addressed this lacuna with a paradigm in which participants first perform (vs. do not perform) actions and then observe another person performing some of the non-performed actions. In this paradigm, observation of videos showing another's actions can later induce false self-attributions of these actions, the observation-inflation effect. Contrary to a sensory-feature account but consistent with a motor-simulation account, we found the effect even with perceptually impoverished action videos in which the majority of sensory features is absent, but motion cues are preserved (Experiment 1). We then created conditions during action observation that should (vs. should not) impede motor simulation. As predicted we found that the effect of observation was reduced when participants executed movements that were incongruent (vs. congruent) with the observed actions (Experiment 2). We discuss the processes that can produce associations of self with observed others' actions and later affect observers' action memory.

Voluntary self-touch increases body ownership

Experimental manipulations of body ownership have indicated that multisensory integration is central to forming bodily self-representation. Voluntary self-touch is a unique multisensory situation involving corresponding motor, tactile and proprioceptive signals. Yet, even though self-touch is frequent in everyday life, its contribution to the formation of body ownership is not well understood. Here we investigated the role of voluntary self-touch in body ownership using a novel adaptation of the rubber hand illusion (RHI), in which a robotic system and virtual reality allowed participants self-touch of real and virtual hands. In the first experiment, active and passive self-touch were applied in the absence of visual feedback. In the second experiment, we tested the role of visual feedback in this bodily illusion. Finally, in the third experiment, we compared active and passive self-touch to the classical RHI in which the touch is administered by the experimenter. We hypothesized that active self-touch would increase ownership over the virtual hand through the addition of motor signals strengthening the bodily illusion. The results indicated that active self-touch elicited stronger illusory ownership compared to passive self-touch and sensory only stimulation, and show an important role for active self-touch in the formation of bodily self.

Seeing Touches Early in Life

The sense of touch provides fundamental information about the surrounding world, and feedback about our own actions. Although touch is very important during the earliest stages of life, to date no study has investigated infants’ abilities to process visual stimuli implying touch. This study explores the developmental origins of the ability to visually recognize touching gestures involving others. Looking times and orienting responses were measured in a visual preference task, in which participants were simultaneously presented with two videos depicting a touching and a no-touching gesture involving human body parts (face, hand) and/or an object (spoon). In Experiment 1, 2-day-old newborns and 3-month-old infants viewed two videos: in one video a moving hand touched a static face, in the other the moving hand stopped before touching it. Results showed that only 3-month-olds, but not newborns, differentiated the touching from the no-touching gesture, displaying a preference for the former over the latter. To test whether newborns could manifest a preferential visual response when the touched body part is different from the face, in Experiment 2 newborns were presented with touching/no-touching gestures in which a hand or an inanimate object—i.e., a spoon- moved towards a static hand. Newborns were able to discriminate a hand-to-hand touching gesture, but they did not manifest any preference for the object-to-hand touch. The present findings speak in favour of an early ability to visually recognize touching gestures involving the interaction between human body parts.

Empathy ≠ sharing: Perspectives from phenomenology and developmental psychology

We argue that important insights regarding the topic of sharing can be gathered from phenomenology and developmental psychology; insights that in part challenge widespread ideas about what sharing is and where it can be found. To be more specific, we first exemplify how the notion of sharing is being employed in recent discussions of empathy, and then argue that this use of the notion tends to be seriously confused. It typically conflates similarity and sharing and, more generally speaking, fails to recognize that sharing proper involves reciprocity. As part of this critical analysis, we draw on sophisticated analyses of the distinction between empathy and emotional sharing that can be found in early phenomenology. Next, we turn to developmental psychology. Sharing is not simply one thing, but a complex and many-layered phenomenon. By tracing its early developmental trajectory from infancy and beyond, we show how careful psychological observations can help us develop a more sophisticated understanding of sharing than the one currently employed in many discussions in the realm of neuroscience. In our conclusion, we return to the issue of empathy and argue that although empathy does not involve or entail sharing, empathy understood as a basic sensitivity to and understanding of others (rather than as a special prosocial concern for others) might be a precondition for sharing.

Evolutionary aspects of self- and world consciousness in vertebrates

Although most aspects of world and self-consciousness are inherently subjective, neuroscience studies in humans and non-human animals provide correlational and causative indices of specific links between brain activity and representation of the self and the world. In this article we review neuroanatomic, neurophysiological and neuropsychological data supporting the hypothesis that different levels of self and world representation in vertebrates rely upon (i) a “basal” subcortical system that includes brainstem, hypothalamus and central thalamic nuclei and that may underpin the primary (or anoetic) consciousness likely present in all vertebrates; and (ii) a forebrain system that include the medial and lateral structures of the cerebral hemispheres and may sustain the most sophisticated forms of consciousness [e.g., noetic (knowledge based) and autonoetic, reflective knowledge]. We posit a mutual, bidirectional functional influence between these two major brain circuits. We conclude that basic aspects of consciousness like primary self and core self (based on anoetic and noetic consciousness) are present in many species of vertebrates and that, even self-consciousness (autonoetic consciousness) does not seem to be a prerogative of humans and of some non-human primates but may, to a certain extent, be present in some other mammals and birds

Mapping the feel of the arm with the sight of the object: on the embodied origins of infant reaching

For decades, the emergence and progression of infant reaching was assumed to be largely under the control of vision. More recently, however, the guiding role of vision in the emergence of reaching has been downplayed. Studies found that young infants can reach in the dark without seeing their hand and that corrections in infants' initial hand trajectories are not the result of visual guidance of the hand, but rather the product of poor movement speed calibration to the goal. As a result, it has been proposed that learning to reach is an embodied process requiring infants to explore proprioceptively different movement solutions, before they can accurately map their actions onto the intended goal. Such an account, however, could still assume a preponderant (or prospective) role of vision, where the movement is being monitored with the scope of approximating a future goal-location defined visually. At reach onset, it is unknown if infants map their action onto their vision, vision onto their action, or both. To examine how infants learn to map the feel of their hand with the sight of the object, we tracked the object-directed looking behavior (via eye-tracking) of three infants followed weekly over an 11-week period throughout the transition to reaching. We also examined where they contacted the object. We find that with some objects, infants do not learn to align their reach to where they look, but rather learn to align their look to where they reach. We propose that the emergence of reaching is the product of a deeply embodied process, in which infants first learn how to direct their movement in space using proprioceptive and haptic feedback from self-produced movement contingencies with the environment. As they do so, they learn to map visual attention onto these bodily centered experiences, not the reverse. We suggest that this early visuo-motor mapping is critical for the formation of visually-elicited, prospective movement control.

Body perception: intersensory origins of self and other perception in newborns

Self-perception involves integrating changes in visual, tactile, and proprioceptive stimulation from self-motion and discriminating these changes from those of other objects. Recent evidence suggests even newborns discriminate synchronous from asynchronous visual-tactile stimulation to their own body, a foundation for self-perception.

Bodily illusions in young children: developmental change in visual and proprioceptive contributions to perceived hand position

We examined the visual capture of perceived hand position in forty-five 5- to 7-year-olds and in fifteen young adults, using a mirror illusion task. In this task, participants see their left hand on both the left and right (by virtue of a mirror placed at the midline facing the left arm, and obscuring the right). The accuracy of participants’ reaching was measured when proprioceptive and visual cues to the location of the right arm were put into conflict (by placing the arms at different distances from the mirror), and also when only proprioceptive information was available (i.e., when the mirror was covered). Children in all age-groups (and adults) made reaching errors in the mirror condition in accordance with the visually-specified illusory starting position of their hand indicating a visual capture of perceived hand position. Data analysis indicated that visual capture increased substantially up until 6 years of age. These findings are interpreted with respect to the development of the visual guidance of action in early childhood.

The consummatory origins of visually guided reaching in human infants: a dynamic integration of whole-body and upper-limb movements

Reaching-to-eat (skilled reaching) is a natural behaviour that involves reaching for, grasping and withdrawing a target to be placed into the mouth for eating. It is an action performed daily by adults and is among the first complex behaviours to develop in infants. During development, visually guided reaching becomes increasingly refined to the point that grasping of small objects with precision grips of the digits occurs at about one year of age. Integration of the hand, upper-limbs, and whole body are required for successful reaching, but the ontogeny of this integration has not been described. The present longitudinal study used Laban Movement Analysis, a behavioural descriptive method, to investigate the developmental progression of the use and integration of axial, proximal, and distal movements performed during visually guided reaching. Four infants (from 7 to 40 weeks age) were presented with graspable objects (toys or food items). The first prereaching stage was associated with activation of mouth, limb, and hand movements to a visually presented target. Next, reaching attempts consisted of first, the advancement of the head with an opening mouth and then with the head, trunk and opening mouth. Eventually, the axial movements gave way to the refined action of one upper-limb supported by axial adjustments. These findings are discussed in relation to the biological objective of reaching, the evolutionary origins of reaching, and the decomposition of reaching after neurological injury.

Putting together phylogenetic and ontogenetic perspectives on empathy

The ontogeny of human empathy is better understood with reference to the evolutionary history of the social brain. Empathy has deep evolutionary, biochemical, and neurological underpinnings. Even the most advanced forms of empathy in humans are built on more basic forms and remain connected to core mechanisms associated with affective communication, social attachment, and parental care. In this paper, we argue that it is essential to consider empathy within a neurodevelopmental framework that recognizes both the continuities and changes in socioemotional understanding from infancy to adulthood. We bring together neuroevolutionary and developmental perspectives on the information processing and neural mechanisms underlying empathy and caring, and show that they are grounded in multiple interacting systems and processes. Moreover, empathy in humans is assisted by other abstract and domain-general high-level cognitive abilities such as executive functions, mentalizing and language, as well as the ability to differentiate another's mental states from one's own, which expand the range of behaviors that can be driven by empathy.

Action, the foundation for cognitive development

It is argued that action constitutes the foundation for cognitive development. Action is a principal component of all aspects of cognitive development including social understanding. It reflects the motives of the child, the problems to be solved, the goals to be attained, and the constraints and possibilities of the child's body and sensory-motor system. Actions are directed into the future and their control is based on knowledge of what is going to happen next. The child's sensory-motor system is especially designed to facilitate the extraction of this knowledge. In addition, the infant is endowed with motives that ensure that these innate predispositions are transformed into a system of knowledge for guiding actions. By acting on the world, infants develop their cognition.