Aren’t those the ripples of theta waves that start to emerge as alpha waves drop while you transition through hypnagogia? On the other end, as you transition o

Aren’t those the ripples of theta waves that start to emerge as alpha waves drop while you transition through hypnagogia? On the other end, as you transition out of sleep to wakefulness, you pass through hypnopompia. I experience the feeling of these waves also when I meditate.