What does the differential amplifier do when both signals are similar?

The differential amplifier is designed to enhance the difference between two input signals while minimizing any common signals shared between them. When both signals are similar, the differential amplifier recognizes that they share a common component. The primary function in this scenario is to eliminate or cancel out that common component, which allows the amplifier to effectively reveal any true difference that may exist between the two signals. This ability to reject common noise or interference that appears in both signals is a critical feature of differential amplifiers, making them advantageous in EEG applications where electrical noise needs to be minimized to accurately capture brain activity. Thus, when the two signals are similar, the differential amplifier will suppress their common characteristics.