| Abstract |
The scope of this thesis is to study the interference that takes place inside a sin-
gle pyramidal neuron belonging to the CA1 region of hippocampus, between two
neuronal signals with di®erent spatiotemporal coordinates. The theoretical frame,
on which this study was accomplished, is de¯ned on a generic computational ap-
proach according to which the morphological components of the neuron have been
compartmentalized into equivalent electrical circuits. The fundamental objectives
of this study are the following two: that of the modulation of excitability of the
modelled CA1 pyramidal neuron under the e®ect of synaptic incoming stimula-
tions having di®erent spatiotemporal characteristics; and, that of the study on the
spatiotemporal information carried in the output signal of the neuron as a result of
the speci¯c features of the incoming synaptic stimulation. The study of the modu-
lation of the excitability of the simulated CA1 neuron under the e®ect of synaptic
stimulations of di®erent spatiotemporal characteristics illustrates the role of the
synaptic mechanism GABAB in the evolution of the spike blocking phenomenon.
Speci¯cally, the analysis of the results obtained, revealed the signi¯cant contri-
bution of the anatomical microstructure in the occurrence of the spike blocking
phenomenon. Furthermore, the hypothesis related to the capability of the neuron
to perceive the number of the dendrites where synaptic clustering occurs, is es-
tablished in correlation to the e±ciency of the blocking spike phenomenon. The
results related to the spatiotemporal study of the information contained during
the ¯nal response of the CA1 neuron led to the conclusion that the spatiotemporal
characteristics of the input signals leave their ¯ngerprint on the ¯nal response of
the neuron. In speci¯c, the spatiotemporal characteristics of the input signal are
mapped in the response of the system, while in general, the spatial characteristics
of the stimulus can be attributed to the intra-burst activity, by employing a coding
in the frequencies space. Moreover, the spectrum of the neuronal discharge varies
between absolute silence and burst depolarization, depending upon the speci¯c
conditions of time delay that apply.
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Χωρική και χρονική πληροφορία στην έχοδο του Μεμονωμένου CA1 πυραμιδικού νεύρωνα
