Assessing the propagation of EEG transient activity

The domain of electroencephalography (EEG) has a long history of research and clinical applications. Its relative ease of deployment, low cost, and high availability have secured for this recording technique a place of choice in the neuroscience and neuromedecine armada. Given these qualities and its important user base, investigation of the central nervous system could largely benefit from the development of new analysis techniques for EEG recordings. This paper contributes to a better exploitation of EEG databases by proposing a new methodology to assess temporal displacements of transient activity of scalp action potential fields. This technique establishes relationships - through a cross-correlation analysis - between the time-frequency representations of different recording channels. An example application is given for the propagation of EEG sleep spindles but larger applicability to other transient waveforms recorded on dense arrays of sensors is also possible.