What does the term 'sensitivity' refer to in EEG monitoring?

The term 'sensitivity' in EEG monitoring specifically refers to the degree of voltage change that is represented per millimeter of pen movement on an EEG record. This measurement is crucial because it affects how well small voltage changes, which correspond to brain activity, are captured and displayed on the EEG paper or screen. A higher sensitivity setting will result in a greater amplitude of signal representation, making it easier to visualize smaller changes in brain activity. Conversely, a lower sensitivity would compress these small changes, making them harder to interpret. This aspect is critical for accurately identifying and analyzing various brain wave patterns that can indicate different states of consciousness, sleep stages, and potential abnormalities.