Différenciation hémisphérique auditive par analyse de potentiels évoqués auditifs

Some studies deal with the hemispheric differentiation versus speech perception. Our concern is to develop objective methods in order to distinguish the behaviours of the right and left auditory cortices. Intracerebral auditory evoked potentials (AEPs) are recorded in response to different sound stimuli. Three methods are proposed. The first one is based on the correlation coefficient between responses to two different sounds recorded on the same sensors. From this first result, we investigate the correlation variation between AEPs in response to two verbal sounds in the course of time. Then, a correspondence analysis is applied and a hierarchic classification is carried out on the factors of the analysis. Finally, AEPs are filtered to estimate the number of extrema they contain according to the stimulus and the hemisphere we consider. This study allows to extract parameters which are characteristic of the behaviour of each cortex.