Question

Which of the following component is generally designed to have a very high value of input impedance to take care of high electrode impedance?

(a) Montages

(b) Filters

(c) Electrodes

(d) Preamplifiers

I have been asked this question in my homework.

This intriguing question comes from Multi-Patient Telemetry topic in division Biomedical Telemetry of Biomedical Instrumentation

Answer 1

The correct option is (c) Electrodes

For explanation: EEG preamplifiers are generally designed to have a very high value of input impedance to take care of high electrode impedance. Good electrode impedance should be generally below 5 kilohms. Impedance between a pair of electrodes must also be balanced or the difference between them should be less than 2 kilohms.