Search results for "brain development"

Isolation and differential expression of two isoforms of the ROBO2/Robo2 axon guidance receptor gene in humans and mice.

2006

AbstractExpression of Robo receptor molecules is important for axon guidance across the midline of the mammalian central nervous system. Here we describe novel isoform a of human ROBO2, which is initially strongly expressed in the fetal human brain but thereafter only weakly expressed in adult brain and a few other tissues. The known isoform b of ROBO2 shows a more or less ubiquitous expression pattern, suggesting diverse functional roles. The genomic structure and distinct expression patterns of Robo2a and Robo2b have been conserved in the mouse, but in contrast to human ROBO2a mouse Robo2a is also abundant in adult brain. Exons 1 and 2 of human ROBO2a lie in an inherently unstable DNA seg…

Refuting the challenges of the developmental shift of polarity of GABA actions: GABA more exciting than ever!

2012

International audience; During brain development, there is a progressive reduction of intracellular chloride associated with a shift in GABA polarity: GABA depolarizes and occasionally excites immature neurons, subsequently hyperpolarizing them at later stages of development. This sequence, which has been observed in a wide range of animal species, brain structures and preparations, is thought to play an important role in activity-dependent formation and modulation of functional circuits. This sequence has also been considerably reinforced recently with new data pointing to an evolutionary preserved rule. In a recent ``Hypothesis and Theory Article,'' the excitatory action of GABA in early …

Influences of prenatal and postnatal stress on adult hippocampal neurogenesis: The double neurogenic niche hypothesis

2015

International audience; Adult hippocampal neurogenesis (AHN) is involved in learning, memory, and stress, and plays a significant role in neurodegenerative and psychiatric disorders. As an age-dependent process, AHN is largely influenced by changes that occur during the pre- and postnatal stages of brain development, and constitutes an important field of research. This review examines the current knowledge regarding the regulators of AHN and the influence of prenatal and postnatal stress on later AHN. In addition, a hypothesis is presented suggesting that each kind of stress influences a specific neurogenic pool, developmental or postnatal, that later becomes a precursor with important repe…

Cellular expression of connexins in the rat brain: neuronal localization, effects of kainate-induced seizures and expression in apoptotic neuronal ce…

2003

The identification of connexins (Cxs) expressed in neuronal cells represents a crucial step for understanding the direct communication between neurons and between neuron and glia. In the present work, using a double-labelling method combining in situ hybridization for Cx mRNAs with immunohistochemical detection for neuronal markers, we provide evidence that, among cerebral connexins (Cx26, Cx32, Cx36, Cx37, Cx40, Cx43, Cx45 and Cx47), only Cx45 and Cx36 mRNAs are localized in neuronal cells in both developing and adult rat brain. In order to establish whether connexin expression is influenced in vivo by abnormal neuronal activity, we examined the short-term effects of kainate-induced seizur…

P27-S Sex differences and cortical excitability in healthy adolescents

2019

Background Sex is known to influence brain development. However, sex differences in cortical excitability and their relationship to motor functions is unclear. Aim We examined the sex related differences in the degree of handedness, left and right motor cortex excitability and manual dexterity. Methods 28 healthy adolescents (age 16–19 years,19 girls) were studied. The degree of right-handedness was determined by the Waterloo Handedness Questionnaire. Motor threshold (MT) of the abductor pollicis brevis was measured on both hemispheres. Box and block test (BBT) was used for manual dexterity. Independent samples t-test was used in statistical analysis. Results There were no differences betwe…

Role of en and novel interactions between msh, ind, and vnd in dorsoventral patterning of the Drosophila brain and ventral nerve cord

2010

AbstractSubdivision of the neuroectoderm into discrete gene expression domains is essential for the correct specification of neural stem cells (neuroblasts) during central nervous system development. Here, we extend our knowledge on dorsoventral (DV) patterning of the Drosophila brain and uncover novel genetic interactions that control expression of the evolutionary conserved homeobox genes ventral nervous system defective (vnd), intermediate neuroblasts defective (ind), and muscle segment homeobox (msh). We show that cross-repression between Ind and Msh stabilizes the border between intermediate and dorsal tritocerebrum and deutocerebrum, and that both transcription factors are competent t…

Epigenetics in Brain Development and Disease

2017

Subjective Experience of Episodic Memory and Metacognition: A Neurodevelopmental Approach

2013

Episodic retrieval is characterized by the subjective experience of remembering. This experience enables the co-ordination of memory retrieval processes and can be acted on metacognitively. In successful retrieval, the feeling of remembering may be accompanied by recall of important contextual information. On the other hand, when people fail (or struggle) to retrieve information, other feelings, thoughts and information may come to mind. In this review, we examine the subjective and metacognitive basis of episodic memory function from a neurodevelopmental perspective, looking at recollection paradigms (such as source memory, and the report of recollective experience) and metacognitive parad…

Hierarchical imaging and computational analysis of three-dimensional vascular network architecture in the entire postnatal and adult mouse brain

2021

The formation of new blood vessels and the establishment of vascular networks are crucial during brain development, in the adult healthy brain, as well as in various diseases of the central nervous system. Here, we describe a step-by-step protocol for our recently developed method that enables hierarchical imaging and computational analysis of vascular networks in postnatal and adult mouse brains. The different stages of the procedure include resin-based vascular corrosion casting, scanning electron microscopy, synchrotron radiation and desktop microcomputed tomography imaging, and computational network analysis. Combining these methods enables detailed visualization and quantification of t…

Neuromagnetic studies of attention in children and youth: Role of exercise and impact on cognitive competence

2023

Tarkkaavuus on monella tavoin yhteydessä elimistömme sisäisiin ja ulkoisiin tekijöihin aivojen kehityksen aikana, jolloin aivot muovautuvat voimakkaasti. Tässä väitöskirjassa tutkitaan tarkkaavuutta kahdesta eri näkökulmasta: millä tavoin oma toimintamme vaikuttaa tarkkaavuuteen ja toisaalta miten tarkkaavuus moduloi muita kognitiivisia toimintoja. Tarkemmin sanottuna väitöskirjassa tutkitaan fyysisen aktiivisuuden ja aerobisen kunnon yhteyksiä ennakoivan tarkkaavuuden ja modaliteettien välisen tarkkaavuuden suuntaamisen aivoperustaan 13-17-vuotiailla nuorilla. Lisäksi väitöskirjassa tutkitaan millä tavoin tarkkaavuus vaikuttaa puheäänteiden ja ei-kielellisten äänteiden käsittelyyn aivoissa…