In the world of EEG research, a paradigm shift is underway. The conventional
wisdom of prioritizing low impedance in pursuit of high-quality electrophysiological
recordings is being reevaluated. Its time to redirect our attention toward a more
meaningful metric: the signal-to-noise ratio (SNR).
For decades, the pursuit of low skin-electrode impedance held great importance.
This belief stemmed from an era when amplifiers drew significant input currents and
data points were meticulously plotted on graph paper. Back then, obtaining a quality
signal required the use of silver-silver chloride electrodes, electrolytes, and even skin
abrasion. The gold standard for EEG recording was set at an impedance of less than 5KΩ.
When coupled with sophisticated signal processing techniques researchers can now attain Impeccable recordings even when dealing with low amplitude signals, such as EEG.
Fast forward to today, and modern amplifiers have revolutionized the landscape.
These advanced devices boast high input impedance, rendering the concern for
significant current draw obsolete. This breakthrough enables stable recordings to be
achieved with substantially higher skin-electrode impedance values. When coupled
with sophisticated signal processing techniques, researchers can now attain
impeccable recordings even when dealing with low amplitude signals, such as EEG.
This progress is particularly evident with the advent of cutting-edge technologies like
dry printed electrodes.
As we embark on this new frontier, its imperative to reassess our assumptions and
embrace the latest advancements in EEG recording. Rather than fixating on the
impedance metrics of the past, our focus should shift towards optimizing the signal-
to-noise ratio. By doing so, we open up doors to unprecedented insights and