Which technique records electrical activity of the brain?

Which technique records electrical activity of the brain?

• A. MRI
• B. CT Scan
• C. EEG
• D. PET Scan

Answer: (C)

EEG records the brain’s electrical activity by picking up the electrical signals generated by neuronal firing. It does this non-invasively with electrodes placed on the scalp, which detect the summed voltage changes from cortical neurons in real time. Because these electrical signals fluctuate on the millisecond scale, EEG has excellent temporal resolution and can track rapid brain dynamics and reveal patterns like sleep stages or epileptic activity. It doesn’t produce detailed images of brain structure, which is what MRI and CT scans provide. PET scans, on the other hand, measure metabolic activity using radioactive tracers, not electrical signals. So the technique that directly records electrical activity of the brain is EEG.

EEG records the brain’s electrical activity by picking up the electrical signals generated by neuronal firing. It does this non-invasively with electrodes placed on the scalp, which detect the summed voltage changes from cortical neurons in real time. Because these electrical signals fluctuate on the millisecond scale, EEG has excellent temporal resolution and can track rapid brain dynamics and reveal patterns like sleep stages or epileptic activity. It doesn’t produce detailed images of brain structure, which is what MRI and CT scans provide. PET scans, on the other hand, measure metabolic activity using radioactive tracers, not electrical signals. So the technique that directly records electrical activity of the brain is EEG.