The Emergence of Human Consciousness: From Fetal to Neonatal Life

Lagercrantz, Hugo; Changeux, Jean‐Pierre

doi:10.1203/pdr.0b013e3181973b0d

Cited by 199 publications

(107 citation statements)

References 71 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The most significant event related to the establishment of thalamocortical connectivity is the appearance of somatosensory evoked potentials (Molliver, 1967;Kostović & Jovanov-Miloše-vić, 2006;Vanhatalo & Kaila, 2006;Kostović & Judaš, 2007;Milh et al 2007). The thalamocortical pathways conducting impulses for pain sensation mature in the same period (Slater et al 2008;Lagercrantz & Changeux, 2009). …”

Section: Penetration Of the Cortical Plate (After 24-26 Pcw)mentioning

confidence: 99%

Development of axonal pathways in the human fetal fronto‐limbic brain: histochemical characterization and diffusion tensor imaging

et al. 2010

View full text Add to dashboard Cite

The development of cortical axonal pathways in the human brain begins during the transition between the embryonic and fetal period, happens in a series of sequential events, and leads to the establishment of major long trajectories by the neonatal period. We have correlated histochemical markers (acetylcholinesterase (AChE) histochemistry, antibody against synaptic protein SNAP-25 (SNAP-25-immunoreactivity) and neurofilament 200) with the diffusion tensor imaging (DTI) database in order to make a reconstruction of the origin, growth pattern and termination of the pathways in the period between 8 and 34 postconceptual weeks (PCW). Histological sections revealed that the initial outgrowth and formation of joined trajectories of subcortico-frontal pathways (external capsule, cerebral stalk-internal capsule) and limbic bundles (fornix, stria terminalis, amygdaloid radiation) occur by 10 PCW. As early as 11 PCW, major afferent fibers invade the corticostriatal junction. At 13-14 PCW, axonal pathways from the thalamus and basal forebrain approach the deep moiety of the cortical plate, causing the first lamination. The period between 15 and 18 PCW is dominated by elaboration of the periventricular crossroads, sagittal strata and spread of fibers in the subplate and marginal zone. Tracing of fibers in the subplate with DTI is unsuccessful due to the isotropy of this zone. Penetration of the cortical plate occurs after 24-26 PCW. In conclusion, frontal axonal pathways form the periventricular crossroads, sagittal strata and 'waiting' compartments during the path-finding and penetration of the cortical plate. Histochemistry is advantageous in the demonstration of a growth pattern, whereas DTI is unique for demonstrating axonal trajectories. The complexity of fibers is the biological substrate of selective vulnerability of the fetal white matter.

show abstract

Section: Penetration Of the Cortical Plate (After 24-26 Pcw)mentioning

confidence: 99%

Development of axonal pathways in the human fetal fronto‐limbic brain: histochemical characterization and diffusion tensor imaging

et al. 2010

View full text Add to dashboard Cite

show abstract

“…15; for a recent review on the mental capabilities of the newborn infant see Ref. 16). Recently, a number of studies have addressed the possibility to use resting-state functional connectivity as a biomarker for neurologic deficits in spatial neglect after stroke in the parietal cortex (17) as well as its potential role in developmental disorders such as attention deficit hyperactivity disorder and autism (see Ref.…”

mentioning

confidence: 99%

Spontaneous Brain Activity in the Newborn Brain During Natural Sleep—An fMRI Study in Infants Born at Full Term

et al. 2009

Self Cite

View full text Add to dashboard Cite

Recent progress in functional neuroimaging research has provided the opportunity to probe at the brain's intrinsic functional architecture. Synchronized spontaneous neuronal activity is present in the form of resting-state networks in the brain even in the absence of external stimuli. The objective of this study was to investigate the presence of resting-state networks in the unsedated infant brain born at full term. Using functional MRI, we investigated spontaneous low-frequency signal fluctuations in 19 healthy full-term infants. Resting-state functional MRI data acquired during natural sleep was analyzed using independent component analysis. We found five resting-state networks in the unsedated infant brain born at full term, encompassing sensory cortices, parietal and temporal areas, and the prefrontal cortex. In addition, we found evidence for a restingstate network that enclosed the bilateral basal ganglia. It is well known that the brain's energy expenditure is considerably larger than what is to be expected from its weight alone. Similar observations have been made in the infant brain (1). Moreover, it has also become apparent that the additional brain energy required to respond to changes in the environment is surprisingly small (2). Taken together, these observations have lead researchers to conclude that a large amount of the brain's activity is spent on tasks that as of yet is unaccounted for (3). Several theories related to the functional role of the brain's intrinsic activity have been proposed. Speculatively, intrinsic brain activity might be related to the neuronal activity necessary to retain a sustained level of maintenance and updating of information flow in the brain. To this end, recent development in functional MRI (fMRI) research has provided the opportunity to gain insights into the brain's intrinsic functional architecture by recording spontaneous, low-frequency blood oxygenation level dependent (BOLD) fMRI signal changes that are present during rest, i.e. in absence of any overt behavior (see Ref. 4 for a recent review). Several studies have shown that spontaneous changes in resting-state fMRI activity is related to the changes in neuronal activity (5,6) and that signal synchronicity across widely separated brain areas exist within multiple so-called resting-state networks in the adult brain (7). Previous reports have shown that functional connectivity in the format of resting-state networks in the adult brain spans brain regions that are involved in sensory perception (8 -10), language (11), and in the so-called default-mode network (12-14). The default-mode network is believed to be involved in different aspects of self-referential mental efforts (see Ref. 15; for a recent review on the mental capabilities of the newborn infant see Ref. 16). Recently, a number of studies have addressed the possibility to use resting-state functional connectivity as a biomarker for neurologic deficits in spatial neglect after stroke in the parietal cortex (17) as well as its potential role ...

show abstract

“…From this particular point of view, many pieces of evidence might be informative with regard to the existence of favored links between hearing and touch, in both animals (e.g., Bleckmann, 2008;Peck, 1994;Popper, 2000) and humans (Marks, 1983;von Békésy, 1959). The onset of function within the systems involved in sensory processing occurs in the following order: from the somesthetic and vestibular modalities to the chemosensory (oral and nasal), the auditory, and lastly, the visual modalities (see Gottlieb, 1971;Lickliter, 2000;Lickliter & Bahrick, 2000; see also Lagercrantz & Changeux, 2009;see Fig. 1).…”

mentioning

confidence: 99%

Audiotactile interactions in temporal perception

2011

View full text Add to dashboard Cite

In the present review, we focus on how commonalities in the ontogenetic development of the auditory and tactile sensory systems may inform the interplay between these signals in the temporal domain. In particular, we describe the results of behavioral studies that have investigated temporal resolution (in temporal order, synchrony/asynchrony, and simultaneity judgment tasks), as well as temporal numerosity perception, and similarities in the perception of frequency across touch and hearing. The evidence reviewed here highlights features of audiotactile temporal perception that are distinctive from those seen for other pairings of sensory modalities. For instance, audiotactile interactions are characterized in certain tasks (e.g., temporal numerosity judgments) by a more balanced reciprocal influence than are other modality pairings. Moreover, relative spatial position plays a different role in the temporal order and temporal recalibration processes for audiotactile stimulus pairings than for other modality pairings. The effect exerted by both the spatial arrangement of stimuli and attention on temporal order judgments is described. Moreover, a number of audiotactile interactions occurring during sensory-motor synchronization are highlighted. We also look at the audiotactile perception of rhythm and how it may be affected by musical training. The differences emerging from this body of research highlight the need for more extensive investigation into audiotactile temporal interactions. We conclude with a brief overview of some of the key issues deserving of further research in this area.Keywords Auditory . Tactile . Temporal . Frequency . Audiotactile . Crossmodal similarities . Mechanoreception . MultisensoryThe boundaries between hearing and touch: the foundation of an analogyWe continuously interact with environments that provide a large amount of multisensory information to our various senses. Researchers have now convincingly demonstrated that the inputs delivered by the different sensory channels tend to be bound together by the brain (see the section Research on hearing and touch: a multisensory perspective for a fuller discussion of this topic). Unlike the audiovisual and visuotactile sensory pairings, those interactions taking place at both the neuronal and behavioral level between audition and touch have, to date, been explored in far less detail (see Kitagawa & Spence, 2006;Soto-Faraco & Deco, 2009, for reviews of the extant literature). The paucity of research covering this modality pairing is rather surprising when one considers the wide range of everyday situations in which we experience-even though often in subtle and unconscious ways-the interplay between these two senses. Examples include perceiving the "auditory" buzzing and the itchy "tactile" sensation of an insect landing on the back of our neck; reaching for a mobile phone ringing and vibrating in our pocket. What is common to these situations is the exclusive-or, at the very least, predominant-reliance on cues provided by the

show abstract

The Emergence of Human Consciousness: From Fetal to Neonatal Life

Cited by 199 publications

References 71 publications

Development of axonal pathways in the human fetal fronto‐limbic brain: histochemical characterization and diffusion tensor imaging

Development of axonal pathways in the human fetal fronto‐limbic brain: histochemical characterization and diffusion tensor imaging

Spontaneous Brain Activity in the Newborn Brain During Natural Sleep—An fMRI Study in Infants Born at Full Term

Audiotactile interactions in temporal perception

Contact Info

Product

Resources

About