Some Mefthods ~ow Dynam~c Ana~ys~s o~ ~he Sca~p lRecordedlErEG

\. Summary: This paper describes methods for quantifying the spatiotemporal dynamics of EEG. Development of these methods was motivaled watching computer.generated animations of EEG voltage records. nl~e animations contain a wealth of information about the p ble feature from each measuremenl epoch. the highest squared voltage among the various electrode sites. Nineteen ch<lnnels ()( ,. were collected (rom subjects using an electrode cap with standard 10-20 system placements. Two minute records wcre obtained. Each record sampled at a rale of 200 per second. Thirty seconds of artifact-free data were extracted from each 2 minute record. An algorithm lhen deterlllJ' Ihe location of Ihe eh.mnelwith the greatest amplitude for each 5 mSec sampling epoch. We quantified these spatio-temporal dynamics as scal~ veclors and cluster .lnalytic plots of EEG activity for finger tapping. cognilive effort (counling backivards) and relaxation to iIIustr<lte the utility'" techniques.