Now since both the OpenLD hardware and software are now more or less completed, here is a 5 second recording of EEG (Fp1-A2), EOG (E1-A2 and E2-A2), and ECG signals, viewed from an open-source software called EDFBrowser.
The signals were recorded when I was awake, with eyes closed. You can see the EEG Fp1-A2 electrode (red), EOG E1-A2 (left eye - yellow) / E2-A2 (right eye - blue) signals, and the ECG (Electrocardiogram - green) signal above.
Note: The reason we need two channels for EOG is due to the fact that the eye movements produce a complementary/out-of-phase signal. For instance, we can see that when the left eye E1-A2 (yellow) trace reflects upwards, the right eye E2-A2 (blue) trace reflects downwards. Other activity that is in-sync/in-phase is NOT eye movement activity.
In the next few Project Logs, I will talk about the implementation and the mathematics of the OpenLD Analysis porgram. Afterwards, I will hopefully post a full sleep recording and evaluate the REM detection performance of the software.