Connectivity in the human fetal brain

Abstract

Event Abstract Back to Event Connectivity in the human fetal brain Ivica Kostovic1* and Lana Vasung1 1 School of Medicine University of Zagreb, Croatian Institute for Brain Research, Netherlands It is generally accepted that complexity of neuronal connections in the human brain underlies complexity of cognitive and behavioral functions. In this paper we explain how developmental cellular events and connectivity patterns form special framework for early functions and establishment of adult circuitry. At the beginning of fetal period distributions of circuitry elements (axons, dendrites and synapses) is strictly bi-laminar outside of proliferative zones. The first quantifiable number of synapses occurs after 15 post conceptional weeks (PCW) in the transient subplate zone. This early synapses are substrate of endogenous, sensory non-driven activity. Distribution within the connectivity compartments is random and no modular units were observed. Important phenomenon in development of afferent input is "waiting" phenomenon: axons "wait" for several months until they gradually invade target cortical area. These waiting synaptic compartments may be visualized in both in vivo and postmortem images. The bipolar orientation of synapses, with predominance of deep circuitry is basis for cortical surface-positive electric response. The majority of described circuitry is transient. It is only after 23 PCW that sensory driven afferents establish connections in the corresponding cortical target area. At the end of gestation another phenomenon take place and that is a dramatic reorganization of fetal circuitry due to the retraction of axons and gradual disappearance of transient fetal layers. In conclusion, early fetal circuitry shows transient laminar distribution and transient endogenous activity. Sensory driven activity is late phenomenon and further development of connectivity proceeds after dramatic spatial and cellular reorganization of cortex. The knowledge on development of fetal circuitry is important for understanding of biological basis of motor sensory and cognitive functions as well as developmental origin of mental and cognitive disorders in men. Conference: Biomag 2010 - 17th International Conference on Biomagnetism , Dubrovnik, Croatia, 28 Mar - 1 Apr, 2010. Presentation Type: Oral Presentation Topic: Fetal and neonatal biomagnetism Citation: Kostovic I and Vasung L (2010). Connectivity in the human fetal brain. Front. Neurosci. Conference Abstract: Biomag 2010 - 17th International Conference on Biomagnetism . doi: 10.3389/conf.fnins.2010.06.00071 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 22 Mar 2010; Published Online: 22 Mar 2010. * Correspondence: Ivica Kostovic, School of Medicine University of Zagreb, Croatian Institute for Brain Research, Zagreb, Netherlands, ikostov@hiim.hr Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Ivica Kostovic Lana Vasung Google Ivica Kostovic Lana Vasung Google Scholar Ivica Kostovic Lana Vasung PubMed Ivica Kostovic Lana Vasung Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.