1. Wireless vs. Wired EEG Application 6137-Algorithms in Network Theory 2013

2. Based on Wireless Recording Systems: From Noninvasive EEG-NIRS to Invasive EEG devices, by M. Savan et al in IEEE Transactions on Biomedical Circuits and Systems, vol. 7, No. 2, April 2013, pp.186-195 Available on Moodle 2

3. Terminology EEG – electroencephalography NIRS – near-infrared spectroscopy Hb0 2 – oxyhemoglobin HbR – de-oxyhemoglobin MICS – Medical Implant Communication System BER – Bit Error Rate 3

4. Noninvasive vs. invasive systems 4

5. Functional diagram – noninvasive systems 5

6. Functional diagram – invasive systems 6

7. NIRS recordings – visual task 1/2 Fig. 8 Measured NIRS recordings (a) NIRS baseline signal (b) Sensor placement and average HbO 2 concentrations for the visual task 7

8. NIRS recordings – visual task 2/2 Fig. 8 Measured NIRS recordings (c) Averaged relative changes of concentration of HbO 2 and HBR 8

9. NIRS recordings – motoric task Fig. 8 Measured NIRS recordings (e) Placement of sensors (f) Averaged relative changes of concentration of HbO 2 and HBR 9

10. Measured noise in EEG 10

11. EEG recorded from different locations 11

12. Localizing the epileptogenic zone 12 Fig. 10 Early seizure onset detection allows localizing the epileptogenic zone

13. Conclusions 1/3 Wireless portable 8 EEG channels 32 NIRS channels Observes hemodynamic activations Records EEG for epilepsy presurgical evaluation 13

14. Conclusions 2/3 Implantable module offers – Great tunability – Programmable gain – Input referred noise of 0.5 μV RMS – Sampling frequency up to 2kbps for 32 channels 14

15. Conclusions 3/3 C# based GUI offers – Easy remote control – Tuneability over the implantable system – MICS band bidirectional communication RF link with BER < 10 -10 (raw channel quality of 10 -3 ) Scalable architecture 15