Which of the following pairs of metals are considered best for clinical EEG recording?

Silver-silver chloride electrodes are widely considered the standard for clinical EEG recording due to their excellent electrochemical properties. These electrodes have a stable and low potential, which minimizes noise and interference, leading to clearer and more reliable EEG tracings. The silver-silver chloride combination helps in providing a good signal-to-noise ratio, essential for capturing the subtle electrical activities of the brain.

Platinum, on the other hand, is also used in some EEG applications due to its biocompatibility and stability, though it is not as common as silver-silver chloride. When combined, these metals offer a durable and stable electrode configuration that is less prone to deterioration and can maintain consistent conductivity over time. This is particularly important in clinical settings where precise readings are crucial for diagnosis and monitoring.

In contrast, other combinations, such as gold and copper, or gold and silver-silver chloride, do not hold the same level of effectiveness or practicality for EEG recording. While gold is occasionally used due to its conductive properties, it is typically more expensive and not as readily used in routine clinical EEGs. Copper, although a good conductor, can cause issues such as electrode polarization and noise, which makes it less suitable for this purpose.