Which diagnostic tool is commonly used to observe brain activity?

The Electroencephalogram (EEG) is a diagnostic tool specifically designed to observe and record the electrical activity of the brain. It does this by placing electrodes on the scalp, which detect the electrical impulses produced by neuronal activity. EEG is particularly useful for diagnosing conditions such as seizures, epilepsy, sleep disorders, and other neurological conditions.

Unlike imaging techniques like X-ray, CT scan, and MRI, which provide structural images of the brain, EEG focuses on the functional aspect by capturing real-time electrical fluctuations, making it immensely valuable in understanding brain function and identifying abnormalities related to electrical activity. This functional assessment is critical for diagnosing and managing a variety of neurological issues, thus underscoring the importance of EEG in clinical settings.