Visualization of significant ERD/ERS patterns in multichannel EEG and ECoG data.
OBJECTIVE
Analysis of event-related desynchronization (ERD) and event-related synchronization (ERS) often requires the investigation of diverse frequency bands. Such analysis can be difficult, especially when using multichannel data. Therefore, an effective method for the visualization of event-related changes in oscillatory brain activity is required.


METHODS
A bootstrap-based method is presented which gives time-frequency maps showing only significant changes of ERD or ERS in predetermined frequency bands.


RESULTS
Examples from an electroencephalographic study and an electrocorticographic study are shown. The results demonstrate how easily reactive channels and their spatio-temporal and frequency-specific characteristics can be identified by means of this method.


CONCLUSIONS
The proposed method is a simple but effective way to visualize significant ERD/ERS patterns.
Graimann
B
B
Department of Medical Informatics, Institute for Biomedical Engineering, Technical University Graz, Inffeldgasse 16a/II, A-8010 Graz, Austria. graimann@dpmi.tu-graz.ac.at
Huggins
J E
JE
Levine
S P
SP
Pfurtscheller
G
G
D000465:Algorithms; D001931:Brain Mapping / Q000379:methods*; D003344:Cortical Synchronization / Q000379:methods*; D003626:Data Display; D003627:Data Interpretation, Statistical; D004569:Electroencephalography / Q000379:methods*; D005071:Evoked Potentials / Q000502:physiology; D006801:Humans