Supervisors' Foreword; Abstract; Publications List of the Author ; Acknowledgements; Contents; Acronyms; 1 Introduction; 1.1 Genesis and Study of the Macroscopic Electrical Activity in the Brain; 1.2 Anatomy and Physiology of the Hippocampal Formation; 1.2.1 Anatomical and Functional Organization of the Hippocampal Formation; 1.2.2 Hippocampal LFP Patterns; 1.3 Goals of the Thesis; References; 2 Methods; 2.1 Experimental Procedures; 2.2 LFP Source Decomposition; 2.2.1 Independent Component Analysis; 2.2.2 Current Source Density Analysis; 2.3 Time-Frequency Analysis of LFPs

2.4 Single Unit Analysis2.5 Modeling of LFPs with Finite Elements Method; References; 3 Current Sources of Hippocampal LFPs; 3.1 Experimental Investigation; 3.1.1 CA1 Region; 3.1.2 DentateGyrus; 3.1.3 Characterization of Hippocampal LFP Sources; 3.2 Finite Elements Simulations of LFP's; References; 4 Theta-Gamma Cross-Frequency Coupling in the Hippocampus-Entorhinal Circuit; 4.1 Sources of Gamma Oscillations in CA1; 4.2 Coherence Segregation of Layer-Specific Gamma Sources; 4.3 Theta-Phase Coordination of Gamma Oscillations in CA1

4.4 Variation of Theta-Coupled Gamma Oscillations Along the CA1 Transversal Axis4.5 Theta-Gamma Cross-Frequency Coupling During a Memory Task; References; 5 Discussion; 5.1 Methodological Challenges in the Study of Brain Oscillations; 5.2 A Novel Approach to the Study of Brain Oscillations; 5.3 Theta-Gamma Dynamics Reveals Network Computations During Behaviour; 5.4 Conclusions; References