Spatial tuning of electrophysiological responses to multisensory stimuli reveals a primitive coding of the body boundaries in newborns

Abstract

The ability to identify our own body and its boundaries is crucial for survival. Ideally, the sooner we learn to discriminate external stimuli occurring close to our body from those occurring far from it, the better (and safer) we may interact with the sensory environment. However, when this mechanism emerges within ontogeny is unknown. Is it something acquired throughout infancy, or is it already present soon after birth? The presence of a spatial modulation of multisensory integration (MSI) is considered a hallmark of a functioning representation of the body position in space. Here, we investigated whether MSI is present and spatially organized in 18- to 92-h-old newborns. We compared electrophysiological responses to tactile stimulation when concurrent auditory events were delivered close to, as opposed to far from, the body in healthy newborns and in a control group of adult participants. In accordance with previous studies, adult controls showed a clear spatial modulation of MSI, with greater superadditive responses for multisensory stimuli close to the body. In newborns, we demonstrated the presence of a genuine electrophysiological pattern of MSI, with older newborns showing a larger MSI effect. Importantly, as for adults, multisensory superadditive responses were modulated by the proximity to the body. This finding may represent the electrophysiological mechanism responsible for a primitive coding of bodily self boundaries, thus suggesting that even just a few hours after birth, human newborns identify their own body as a distinct entity from the environment.

Narrative and Bodily Identity in Eating Disorders: Toward an Integrated Theoretical-Clinical Approach

“…The ability to recognize one’s own body and its boundaries as an entity distinct from the environment seems to develop within a few hours of birth ( Ronga et al, 2021 ): by distinguishing whether an auditory or tactile stimulus comes from near or far from one’s own body, the infant is able to develop defensive behaviors and relational mechanisms. Thus, it appears that newborns are already able to make multisensory responses by distinguishing body-related stimuli from stimuli from the environment and that this ability is modulated by the proximity of these stimuli to the body.…”

“…Thus, it appears that newborns are already able to make multisensory responses by distinguishing body-related stimuli from stimuli from the environment and that this ability is modulated by the proximity of these stimuli to the body. The near-body space would be represented from the earliest stages of life, predisposing individuals to direct their actions toward a goal, interact with people, respond to threats, and build a coherent bodily representation of themselves ( Ronga et al, 2021 ).…”

“…The near-body space would be represented from the earliest stages of life, predisposing individuals to direct their actions toward a goal, interact with people, respond to threats, and build a coherent bodily representation of themselves (Ronga et al, 2021).…”

“…The individual builds his or her own bodily self during the pre-linguistic stage, in early interactions with the caregiver, and in the progressive differentiation between self and other through the encoding of sensory stimuli. Given the close relationship between somatosensory processing and the formation of the self-concept demonstrated in studies of embodied cognition ( Meteyard et al, 2012 ) and in recent neuroimaging studies ( Ronga et al, 2021 ), the purpose of this article is to examine the relationship between somatic and narrative memory from the perspective of identity construction early in life. Since bodily representations are the main tools for the generation of meaning, the organization of experiences, and the shaping of social identity, the first part of the article discusses the connection between somatic memory, narrative memory, identity construction, and eating disorders.…”

NEAR: An artifact removal pipeline for human newborn EEG data

“…Studying human newborns in the first days of life provides key insights on the neurocognitive predispositions that humans are endowed with before interacting with the outside world. While most of the research in this field is behavioural, the recent availability of high-quality Electroencephalography (EEG) systems suitable for newborns opened the way to an increasing number of investigations on the neural bases of such predispositions with EEG ( Beauchemin et al, 2011 , Buiatti et al, 2019 , Fifer et al, 2010 , Ronga et al, 2021 ).…”