000109930 001__ 109930
000109930 005__ 20181205220126.0
000109930 0247_ $$2doi$$a10.5075/epfl-thesis-3907
000109930 02470 $$2urn$$aurn:nbn:ch:bel-epfl-thesis3907-9
000109930 02471 $$2nebis$$a5407137
000109930 037__ $$aTHESIS
000109930 041__ $$aeng
000109930 088__ $$a3907
000109930 245__ $$aAnalysis of information processing in the olfactory bulb by in vivo experiments and theoretical modelling
000109930 269__ $$a2007
000109930 260__ $$aLausanne$$bEPFL$$c2007
000109930 300__ $$a223
000109930 336__ $$aTheses
000109930 502__ $$aCarl Petersen, Nicolas Brunel, Rainer Friedrich
000109930 520__ $$aMuch information is conveyed to animals by the diverse molecules propagated in their environment. This information is transmitted and treated within the olfactory system to be utilized by the rest of the brain. In this process, the sensory flow arriving from the nose first encounters the olfactory bulb. This thesis studies different aspects of the encoding and treatment of olfactory information in the bulb by a combination of experimental and theoretical approaches. The olfactory bulb consists of two functional stages: an input stage where the nerve terminals from the sensory neurons of the nose are spatially arranged in a precise manner, and an output stage corresponding to the neurons which propagate the processed information towards the more central brain areas. The first part of this thesis is focused on the development of an image processing technique to precisely map the input stage. In a second part, output neurons activity in responsive areas of the bulb was recorded in anaesthetized mice. The data obtained indicate complex dynamics in neural activity on several time scales. We show that the combination of mean firing rates from a large enough ensemble of neurons allows to accurately predict the odor presented to the animal. We also show that temporal variables related to the dynamics give very little information complementary to the ensemble rate code, suggesting that these variables are not read by brain structures downstream to the bulb. In a third part, we developed a numerical model of the olfactory bulb to understand its fast oscillatory dynamics. The model proposes a mechanism based on the negative feedback from the interneurons that regulate output neurons. Some predictions of the model are checked experimentally. An analytical interpretation of the model is also proposed and its generalization to the analysis of fast oscillation in other parts of the brain is discussed.
000109930 6531_ $$aOlfactory Bulb
000109930 6531_ $$aOptical Imaging
000109930 6531_ $$aWavelet Transform
000109930 6531_ $$aNeural coding
000109930 6531_ $$aNeural Dynamics
000109930 6531_ $$aGamma Oscillations
000109930 6531_ $$aBulbe Olfactif
000109930 6531_ $$aImagerie Optique
000109930 6531_ $$aTransformation en Ondelette
000109930 6531_ $$aCodage Neuronal
000109930 6531_ $$aDynamique Neuronale
000109930 6531_ $$aOscillations Gamma
000109930 700__ $$0240581$$aBathellier, Brice$$g162059
000109930 720_2 $$0240007$$aGerstner, Wulfram$$edir.$$g111732
000109930 720_2 $$aCarleton, Alan$$edir.
000109930 909C0 $$0252006$$pLCN
000109930 909CO $$ooai:infoscience.tind.io:109930$$pthesis$$pthesis-bn2018$$pDOI$$pIC$$pSV$$qDOI2
000109930 918__ $$aIC$$cISIM$$dEDNE
000109930 919__ $$aLCN1
000109930 920__ $$a2007-9-28$$b2007
000109930 970__ $$a3907/THESES
000109930 973__ $$aEPFL$$sPUBLISHED
000109930 980__ $$aTHESIS