Which neurodiagnostic test is primarily used to assess brain electrical activity and is especially sensitive for detecting epilepsy?

• A. Lumbar Puncture
• B. Nerve Conduction Study
• C. Electroencephalography (EEG)
• D. CT Scan

Answer: (C)

Evaluating brain electrical activity and identifying epilepsy hinges on recording the brain’s signals with electroencephalography. EEG uses electrodes on the scalp to pick up the collective electrical activity of neurons in the cortex. In epilepsy, it reveals characteristic patterns such as interictal spikes, sharp waves, and rhythmic discharges, which help confirm diagnosis and guide treatment. The test is noninvasive and can be performed for short or extended periods, including video-EEG monitoring to capture seizures.

Lumbar puncture analyzes cerebrospinal fluid for infection, inflammation, or bleeding, not brain electrical activity. Nerve conduction studies assess peripheral nerves, not the brain. CT scans provide structural brain images to detect lesions or hemorrhages but do not measure electrical activity. So, EEG is the test that best assesses brain electrical activity and is especially sensitive for detecting epilepsy.