What instruction should a nurse provide to a client scheduled for an EEG?

The correct instruction for a client scheduled for an EEG is to thoroughly shampoo hair prior to the test. This is important because the electrodes used in an EEG need to have good contact with the scalp to accurately record brain activity. Any excess oil, dirt, or hair products can interfere with the electrode placement and the quality of the readings.

Having clean hair ensures that the electrodes will adhere properly and minimizes disruptions in the recordings. Other choices like avoiding caffeine, eating a light meal, or bringing a book to read do not address the critical preparation needed to ensure the EEG results are valid and reliable. While these instructions may have their relevance, they do not directly contribute to the functionality of the EEG as clean hair does.