What is the function of a differential amplifier in an EEG setup?

In an EEG setup, the function of a differential amplifier is to amplify the difference in electrical potential between two inputs. This is crucial because EEG measurements involve detecting the small electrical signals generated by neuronal activity in the brain. The use of a differential amplifier helps eliminate common noise and interference that may affect both inputs equally, allowing for a clearer and more accurate representation of the voltage fluctuations that are specifically associated with brain activity.

By focusing on the differences between the inputs, the differential amplifier enhances the signal of interest while suppressing any potential common mode noise, such as electrical interference from the environment or physiological signals from muscle activity. This capability is essential in clinical and research settings, where precision in capturing brain activity is paramount for accurate diagnosis and analysis.