Thesis - Instituto de Telecomunicações

3.4. MATERIALS AND METHODS 53had the electrodes and respective cables, cleaning and conductive materials, and auxiliarybands to hold the several types of electrodes. In order to easily move the subject from thepreparation table to the computer, he was seated in an turnable chair with wheels.In figure 3.11 the disposition of the several elements used in the acquisition protocol areidentified.Figure 3.11: Room diagram.The electrophysiological data acquisition system was a Thought Technologies ProComp2,that has 8 analog acquisition channels, 2 of them sampled at 2048 Hz and the other 6channels sampled at 256 Hz. All the channels were used; the association between eachchannel and signal is presented in table 3.5.In figure B.8 the subject is in a final preparation step where he is already placed infront of the computer, prepared to start the cognitive tests, and we are verifying the qualityof the signals and readjusting the position of the electrodes. In the photos of figure B.10we present two views of the subject table when everything was ready to start the signalacquisition.