Robust Extraction of the N1-Effect in Dichotic Listening Using Hardy Space Mappings of Auditory Late Single Trials

It is known that signs of (early) auditory selective attention are reflected in the N1-wave of auditory late potentials. In recent years, we have analyzed this N1-effect using multiscale neurofunctional modeling and (instantaneous) phase synchronization measures of Hardy space mapped data. To acquire the electroencephalographic data in dichotic listening, we repeated the seminal experiment of Hillyard et al. which first described the N1-effect. Here we apply for the first time phase synchronization measures to these dichotic data and compare the results to the conventional time-domain analysis. Our results suggest that a single trial synchronization analysis of the instantaneous phase at the alpha/theta-border shows the N1-attention effect even more clear than the original averaged time-domain representation. It is concluded that the presented method is a robust tool to analyse (early) signs of selective attention in dichotic listening tasks.