So neural oscillations, also known as brain waves, are constant in a live brain.

The frequency (how fast the waves are) of these oscillations changes based on activity and location . Being awake or asleep, doing a demanding task or not, if the task is audio or visual. Etc. )

When you are asleep there are different oscillations that you cycle through on a fairly predictable pattern.

However this can be altered by many things including drugs and medications. And health problems. Even environment stress and such.

When you are unconscious from anesthesia , you don't get typical sleep pattern but different kinds of patterns. These are predictable too.

https://hms.harvard.edu/news-events/publications-archive/brain/anesthesia-brain

"According to Brown, anesthetic drugs cause brain circuits to change their oscillation patterns in particular ways, thereby preventing neurons in different brain regions from communicating with each other. The result is a loss of consciousness—an unnatural state that he compares to a “reversible coma”—that differs from sleep. The oscillations vary, he explains, based on the type and amount of anesthetic used and the age of the patient’s brain (since brains age at different rates). These powerful drugs can cause mental side effects that often linger for days, months or longer."

https://en.wikipedia.org/wiki/Neural_oscillation

We are definitely getting into a more complex area of neuroscience.

https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2025.1604173/full

This dense paper is on some recent research on locked-in patients and explains in the literature-review section how research on neural oscillations changed artificially with anesthesia has helped them more accurately investigate locked-in syndrome. Explains how these oscillations change in a coma state.

This is not my area of study. But if you have any simple questions about how this works I can probably answer them. Wikipedia might be more useful tho. The "Function" section is most informative.