Strange Signal Drift

[Nathan5653]

Hi everyone,

Just discovered this forum a few days ago and I've learnt a lot while browsing it. Thank you to all who've asked questions and taken the time to answer them! Recently, I was recording EEG and noticed this strange drifting in the EEG signal. I've seen this before but I have no idea what it means. For extra info, the participant was wearing closed-ear headphones and their head was on a chinrest.

Kind regards,
Nathan

[Coen]

Drifts like that are usually caused by perspiration. The sweat disturbs the skin-gel-electrode interface. Try to maintain a comfortable cool environment for the subject. Be careful with fans because electric motors close to the subject may cause interference.

Best regards, Coen (BioSemi)