Program 2011 - Neurowissenschaftliche Gesellschaft eV - MDC

Symposia
Symposia
SYMPOSIUM 22, SUNDAY, MARCH 27, 9:00 - 12:00
Introductory Introductory Remarks Remarks to to Symposium Symposium 22
22
Unravelling Unravelling the the activity-dependent
activity-dependent
mechanisms mechanisms of of network network formation formation in
in
the the neonatal neonatal cortex
cortex
Ileana L. Hanganu-Opatz and Kai Kaila, Hamburg and
Helsinki (Finland)
During the last years, an impressive body of knowledge has
been accumulated on the mechanisms by which activity
influences the development of cortical architecture and
function. Whereas molecular cues set the coarse
organization of the cortical circuits, it is the early electrical
activity, either experience-dependent or – independent, that
refines them. The symposium aims at providing a
comprehensive overview of recent key findings. Thus, it will
offer an up-to-date presentation of the mechanisms
underlying the maturation of cortical circuits under
physiological and pathophysiological conditions. The first
two presentations (Kanold, Akerman) will focus on the
establishment of early neuronal circuits in developing
sensory cortices. The lecture by Patrick Kanold will highlight
the role of transiently-expressed neurons, the subplate
neurons in the development of functional brain organization
and acquirement of sensory perception. The mechanisms
controlling the establishment of synaptic circuits in the visual
system are the main topic of the lecture by Colin Akerman,
who will present new findings on how glutamatergic and
GABAergic inputs converge onto single neurons and how
these inputs are altered by early sensory experience. The
talk by Werner Kilb will present evidence that neurotransmitter
systems can activate particular presynaptic GABAergic
neurons and give rise to distinct temporal patterns of
GABAergic activity in the immature neocortex. In addition,
it will be shown that conditions that induce high frequency
activation of GABAergic inputs can influence the intracellular
Cl- homeostasis and thus GABAergic actions. The role of
cation-chloride cotransporters in the development and
plasticity of cortical circuitry and the effects of
pathophysiological activity (e.g. neonatal seizures) on the
function of the cation-chloride cotransporter KCC2 will be
the main topics of the lecture by Peter Blaesse. Besides
interfering with the development of neuronal networks in
sensory cortices, the early patterns of electrical activity
control the maturation of cortico-hippocampal-subcortical
networks that are responsible for mnemonic and executive
abilities. Ileana Hanganu-Opatz will illustrate the ability of
coordinated hippocampal and subcortical activity to drive
the maturation of the prefrontal cortex, whereas Sudhir
Sivakumaran will lecture on the mechanisms controlling the
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