Researchers interested in brain wave activity are most likely to use electroencephalography (EEG) as their brain scan method. EEG directly records the brain’s electrical activity via electrodes placed on the scalp, capturing the oscillatory activity of large groups of neurons, which correspond to different behavioral states including sleep stages
. EEG is favored because it provides very high temporal resolution (up to milliseconds), is non-invasive, portable, relatively inexpensive, and allows for long-term monitoring of brain states such as engagement, motivation, or drowsiness
. While other imaging techniques like fMRI and PET measure brain activity indirectly through blood flow changes and have better spatial resolution, EEG is uniquely suited for capturing the fast electrical oscillations that define brain wave activity during sleep and wakefulness
. Thus, for studying brain wave activity, especially in contexts like sleep research, EEG is the primary and most practical tool used by researchers.
