Gamma-band synchronization in the neocortex: novel analysis methods and their application to sensory and motivational systems

[摘要] Vinck et al. develop new statistical techniques for the analysis of electrophysiological brain data, and applied these techniques,to the study of brainwaves in sensory and motivational systems. Chapter 2 develops a new measure of phase locking between,spike trains and Local Field Potentials (LFP) that is unbiased for firing rate and spike count. Chapter 3 develops a new measure,of phase synchronization between EEG/MEG/LFP signals that is robust against the effects of volume conduction, noise and sample,size bias. Chapter 4 examines the effect of measurement noise on Granger causality statistics, and finds that statistical,control using time series reversal provides a viable solution for the noise problem, as opposed to examination of the slope,of the coherency function. Chapter 5 develops a new estimator of the entropy function based on polynomial expansion of the,entropy function and Bayesian estimation. Chapters 6-8 apply these techniques to experimental spike and LFP data obtained,from the awake rat using multi-areal ensemble recordings. Chapter 6 shows (1) the presence of band-limited gamma-band (30-90,Hz) oscillations in the barrel cortex, (2) cell-type-specific entrainment of cells by this gamma rhythm, and (3) absence of,gamma phase-coupling with other structures (visual and perirhinal cortex, hippocampus). Chapter 7 shows learning-dependent,gamma oscillations in the orbitofrontal cortex, expressed predominantly by a specific class of cells ('action-value cells’).,Chapter 8, the authors show that neuronal coding of odour-value associations and rhythmic synchronization in OFC is critically,dependent on the NMDA receptor.,

[发布机构] University of Amterdam