The influence of amplifier, interface and biological noise on signal quality in high-resolution EEG recordings

First, the intrinsic random noise sources of a biopotential measurement in general are reviewed. For the special case of an electroencephalographic (EEG) measurement we have extended the commonly used amplifier noise model by biological generated background noise. As the strongest of all noise sources involved will dominate the resulting signal to noise ratio (S/N), we have investigated under which conditions this will be the case. We illustrate experimentally that up to 100 Hz S/N practically depends only on cortical generated background noise, while at a few hundred Hz or more amplifier and thermal noise of interelectrode resistance are the major sources.

[1]  J. Johnson.  Thermal Agitation of Electricity in Conductors , 1928 .

[2]  A. Nightingale,et al.  Background noise in electromyography. , 1959, Physics in medicine and biology.

[3]  Y. Netzer,et al.  The design of low-noise amplifiers , 1981, Proceedings of the IEEE.

[4]  J. Rosell,et al.  Skin impedance from 1 Hz to 1 MHz , 1988, IEEE Transactions on Biomedical Engineering.

[5]  I. Kanazawa,et al.  Somatosensory evoked high-frequency oscillation in Parkinson's disease and myoclonus epilepsy , 1999, Clinical Neurophysiology.

[6]  P. Jaskowski,et al.  Amplitudes and latencies of single-trial ERP's estimated by a maximum-likelihood method , 1999, IEEE Transactions on Biomedical Engineering.

[7]  R Pallás-Areny,et al.  Ag-AgCl electrode noise in high-resolution ECG measurements. , 2000, Biomedical instrumentation & technology.

[8]  Masaru Yarita,et al.  Detection Limit in Low‐amplitude EEG Measurement , 2003, Journal of clinical neurophysiology : official publication of the American Electroencephalographic Society.

[9]  L Trahms,et al.  A template-free approach for determining the latency of single events of auditory evoked M100. , 2005, Physics in medicine and biology.

[10]  C. Grimbergen,et al.  Investigation into the origin of the noise of surface electrodes , 2002, Medical and Biological Engineering and Computing.

[11]  E. Novakov,et al.  Noise of surface bio-potential electrodes based on NASICON ceramic and Ag−AgCl , 1996, Medical and Biological Engineering and Computing.

[12]  P. Fitch.  Signal/noise ratio in the recording of human nerve-action potentials , 1973, Medical and biological engineering.