Some users have difficulty getting a clean EEG. When proper techniques are followed, and the environment does not have excessive interference, there should be no problem getting excellent EEG’s. Please refer to the information below, if you need to improve the quality of your EEG’s.
In extreme cases when using your Discovery, you might notice a 15-16Hz and/or approximately 28 Hz noise that does not seem natural, and is more or less sustained. It might be on one channel, possibly Fz or Pz, or on more than one channel. It is due to a combination of extreme environmental noise, and non-optimal sensor placement. If the electro-cap “puffs” up, it can also cause this problem. Technically, it is due to a 240 Hz power line harmonic that is aliased by the 256 sps sampling rate to look like 16 Hz. This noise is now entirely avoidable, using a free firmware update to the Discovery, available for all Discoveries June 29, 2011. The update can be done remotely, without having to send your Discovery to BrainMaster. Please contact BrainMaster at 440 232-6000 or at support@brainm.com to ensure that your Discovery has the latest firmware. We will schedule a time to get you this update. This new firmware pre-samples the EEG at 512 Hz, and then filters and reconstructs it at 256 Hz. This operation reduces this type of noise by a factor of at least 100,000.
If you have the new firmware, and still seem to have problems with noise, please refer to the following:
Cap
Device Position/Office Arangement
Powered by BetterDocs
You must be logged in to post a comment.