In order to learn more about how the brain works, analysis of its electric activity (so-called language of the brain) is a desired approach. The raw signal as German discoverer Hans Berger recorded it for the first time is not suitable. However, quantitative analysis by frequency analyis using Fast Fourier Transformation (FFT) provides a tool to characterize this activity in detail. Documentation of regional electric power by translating the results into spectral colours followed by additive colour mixture (like RGB mode in TV) documents all frequency changes within one map. Regional distribution of these changes as so-called Enkephaloglyphs can now be related to cognitive and emotional states of the brain. Due to a recent progress in software development various states of the brain can now be analysed within a time window of less than 0.4 seconds (about 3 pictures / second).
neoCateem EEG-based Neuro-Imaging
Cortical distribution of spectral frequencies during performance of a memory test with selective spectral theta wave increases (sweep length 364 ms). Since Hans Berger`s discovery of human electric brain waves, evaluation and interpretation of what he called an Elektroenkephalogramm (EEG) has remained a challenge to neurologists and brain researchers up to date. Already in 1932, Dietsch and Berger suggested quantitative frequency analysis of the signal. But, every day practice had to await help from computers in order to manage the needed mathematical transformation called Fast Fourier Transformation (FFT) resulting in a quick and objective description of the EEG. Computer aided on-line construction of electric brain maps now allows to follow brain activity in real time. The software package CATEEM - developed with proprietary computer systems about 20 years ago has now been translated to run under the operating system Windows as neoCateem. Nearly 3 maps per second are delivered for example during fast mental activities (s. figure). This opens the door for psychophysiological research for example in combination with eye tracking as well as for neurological diagnosis. Recording from 16 physical EEG channels corresponds to otherwise use of 64 electrode positions for mapping in conventional EEG settings.
neoCateem in Market Research
The biggest advantage of conventional EEG recording is the high time resolution, with which data can be gathered from different brain areas. Unfortunately, the raw signal cannot be interpreted in an objective reproducible manner. The most common way to achieve quantitative assessment is spectral frequency analysis by use of Fast Fourier Transformation (FFT). We recently discovered a method of documentation of ultrafast periods of 364 milliseconds. This has opened a new dimension of quantitative EEG analysis. Corresponding numerical values together with a brain map are now called an Enkephaloglyph. The map contains frequency ranges coded into spectral colors, which are presented as an additive color mixture. An example of such a short time period of EEG recording is documented during an eye-gaze on a TV commercial. The new approach of high time resolution quantitative EEG will enable us to set up a library of enkephaloglyphs of brain electric activity related to individual mental reactions (memory!) or emotions.
neoCateem in Pharmacology
Quantitative assessment of drug action has been followed now for about 20 years with CATEEM. Spectral frequency changes in different brain regions are calculated and fed into a linear discriminant analysis (17 brain regions x 6 frequency ranges = 102 variables). The results are displayed by means of a 6-dimensional plot: Result of the first three functions is coded into space (x, y and z axis), results from next three functions into color (RGB mode like used in TV). Drug action is now discriminated according to differences in change of spectral frequencies as determined by source density evaluation of the quantitative EEG (Results from this type of assessment correspond to those of Magnetencephalography). Similar drug action is recognized by close neighborhood and similar color (This kind of evaluation is not part of the commercially available software package). Thus, during clinical studies dose as well as time dependent changes of electric brain activity can be monitored.
neoCateem Tracking Module
Neurocode Tracking (fast dynamic quantitative EEG recording with epoch length of 364 ms) in combination with Eye Tracking allows to follow individual reactions of the brain in response to presentation of advertisements. The short epochs can be related to single glances of the subject. For more information please visit NeuroCode Tracking Software.
- Pattern of all frequency changes is documented within one single map.
- Highest time resolution is sweep length of 364 ms to produce one map.
- Online moving average possible up to 3 minutes for neurological research applications.
- Automatic comparison of 102 EEG parameters to data-base containing hundreds of healthy brains.
- Data recorded and documented in a voltage mode or surface charge mode.
- Source Density, results correspond to MEG.
- Power within six specially defined frequency bands reflects changes of particular neurotransmitter action.
- Continous measurement of depth of sleep by a patented algorithm.
- We can display Topographical online real-time representation.
- Chronology of the frequency changes.
- Electrical power in uV2 or as global median presented as bargraph for each electrode.
- Parameter SFx (sleep frequency index) for determination of depth of sleep (patented algorithms).