National League for Nursing (NLN PAX) Practice Exam

The electroencephalogram (EEG) is a diagnostic tool specifically designed to measure and record the electrical activity of the brain. It captures the impulses of nerve cells within the brain, allowing physicians to observe the neural activity and identify any abnormalities or disruptions in brain function. The EEG is particularly useful for diagnosing conditions such as epilepsy, sleep disorders, and other neurological disorders, as it provides insights into the brain's overall health and functionality.

Understanding the other options helps clarify why they do not relate to the purpose of an EEG. For instance, the impulses of muscle cells of the heart pertain to an electrocardiogram (ECG), which tracks heart activity rather than brain activity. Pressure within the eye is measured by tonometry, and the amount of air upon exhalation is assessed through spirometry, both of which are unrelated to brain function. The specificity of the EEG in capturing brain impulses distinguishes it as the correct choice when discussing tools for examining the brain's electrical activity.