Final answer:
Deep sleep is characterized by the production of delta waves, which have a low frequency and high amplitude. These waves are important for the restoration and rejuvenation of the body.
Step-by-step explanation:
During deep sleep, the brain produces delta waves, which have a low frequency of less than 3 Hz and a high amplitude. Delta waves are the slowest brain wave patterns that occur during sleep and are also known as slow-wave sleep.
These waves are associated with the deepest stage of sleep and are important for the restoration and rejuvenation of the body. Delta waves are responsible for the physical and mental benefits of deep sleep, such as enhanced memory consolidation and hormone regulation.