Enkephaloglyphes

Spectral Signatures of Electric Brain Activity

The New Dimension of Quantitative EEG

The biggest advantage of conventional EEG recording is the high time resolution, with which data can be gathered from different brain areas. Unfortunately, the continuously depicted signal cannot be interpreted in an objective reproducible manner. This asks for quantitative assessment. The most common way to achieve this is spectral frequency analysis by use of Fast Fourier Transformation (FFT). We recently discovered a method of transforming ultrafast periods of 364 milliseconds. This has opened a new dimension of quantitative EEG analysis. An example of such a short time period of the EEG recording is documented in the figure obtained during an eye-gaze on an advertisement during the course of a sport event. The corresponding numerical values together with a brain map are now called an enkephaloglyph. The map contains 140 frequency ranges coded into spectral colors, which are presented as an additive color mixture.

The new approach of high time resolution quantitative EEG will enable us to set up a library of enkephaloglyphes of brain electric activity related to individual thoughts or emotions. Also, during cognitive research new insights into i.e. memory processes are expected.

Dimpfel W and Hoffmann H-C Simultaneous eye tracking and fast dynamic EEG current source density imaging for assessment of commercials or web sites: ECEM 2011, Marseille, France, Innovative methodologies & technologies p.49