Can sleep frequencies be detected from all points of the head, or are some spots better than others?

Traditionally, when recording sleep via the gold standard methodology, polysomnography (PSG), brain wave frequencies are detected from several areas on the head – including from the Frontal (the front of your head), Parietal (the top of your head), and Occipital lobes (the back of your head).

Depending on what stage or feature of sleep you are trying to detect, different areas of the head are better than others. For example, a key feature of Deep sleep is slow wave activity (slow, 0.5-4Hz, high amplitude waves) which is more easily detected in the Frontal lobe. However, wake is often detected by alpha activity (about 8-12Hz), which is more prominent in the Occipital lobe.

In addition, some information other than brainwaves can be useful in detecting sleep stages. In REM sleep, for instance, rapid eye movements and very low muscle activity are generally detected by sensors on the face–near the eyes for the former, and under the chin for the latter. In a PSG, other sensors are commonly used as well, including sensors for respiratory, cardiac and movement events.

Zeo detects a single channel of electrical activity collected at a position that is Frontal-Polar (the forehead), which includes information from the Frontal lobe, some eye movements, and some muscle activity. But since you’d have to shave your head to put the headband on backwards, or use glue to stick sensors in your hair, the forehead seems to be a good place for a dry sleep sensor.

Related Questions:

• How does Zeo score sleep stages less than 2 minutes long?
• What kinds of brain activity can Zeo measure?

Still have questions?  Ask yours here

Back to the Archive