Which of the following is NOT a source of 60Hz interference?

The correct choice pertains to understanding the sources of 60Hz interference in an EEG context. This interference typically arises from electronic devices and electrical systems operating at the frequency of the power supply, which is 60Hz in many regions, particularly in North America.

Equipment in the room, faulty ground connections, and defects in the power supply are all factors that can introduce or amplify this interference. Various electronic devices, such as monitors and fluorescent lights, can emit electromagnetic interference, while poor grounding can lead to significant noise in the EEG signal due to potential differences affecting the reference electrodes. Likewise, defects in the power supply can cause fluctuations that manifest as 60Hz noise in recorded signals.

In contrast, an intravenous drip does not inherently produce such electromagnetic noise as it is not an electrical device but rather a medical delivery system. Therefore, it is not a source of 60Hz interference. This distinction highlights the importance of separating mechanical systems from electrical interference sources when considering factors that could disrupt EEG readings.