Data disrepency
Posted: Tue May 14, 2013 3:23 pm
Hi all,
I wondered if anyone could help me. I have begun data analysis in BESA after collecting the data using the Biosemi system. The majority of the data I opened in BESA looks fine, however for two subjects there is an extreme amount of noise across all electrodes... almost as if the reference electrodes have bridged however this data looks completely different to how the data looked in real time during collection. I don't understand what has happened?! I would not have run the experiment if the electrode offsets were too high and there was a major problem... all the data looked fine but in BESA it looks like a mess. If I set the reference to original average reference the problem goes away but I don't want to do that without knowing what might have caused the problem. Any suggestions/ideas from all would be appreciated as I am a PhD student and a novice at using EEG. If anyone needs additional information for clarification let me know - I can send screen shots if required. I have spoken to others but no one seems to know what has happened.
Thanks in advance.
Confused Karima
I wondered if anyone could help me. I have begun data analysis in BESA after collecting the data using the Biosemi system. The majority of the data I opened in BESA looks fine, however for two subjects there is an extreme amount of noise across all electrodes... almost as if the reference electrodes have bridged however this data looks completely different to how the data looked in real time during collection. I don't understand what has happened?! I would not have run the experiment if the electrode offsets were too high and there was a major problem... all the data looked fine but in BESA it looks like a mess. If I set the reference to original average reference the problem goes away but I don't want to do that without knowing what might have caused the problem. Any suggestions/ideas from all would be appreciated as I am a PhD student and a novice at using EEG. If anyone needs additional information for clarification let me know - I can send screen shots if required. I have spoken to others but no one seems to know what has happened.
Thanks in advance.
Confused Karima