victoria is listening to a lecture in a hot lecture hall, late on a friday afternoon. she starts to feel drowsy and then falls into a light sleep. if her brain-wave patterns were being monitored, they would show a shift from

The answer to the question is a change from beta waves to alpha waves and finally to theta waves. These waves are part of the five brainwaves that signify our levels of consciousness, together with delta and gamma.

Beta waves are recorded when we are awake – a condition when we are at our most alert, which for Victoria, is when she is still listening to the lecture. Alpha waves appear when we are deeply relaxed, when we are daydreaming or at a light meditative state – which for Victoria occurs when she starts feeling drowsy. Theta waves for Victoria is when she is asleep – specifically, when she has fallen into REM dream state.