Across
- 2. An unpleasant dream
- 4. Existing in thought or as an idea
- 7. The sleep hormone
- 8. The feel-good neurotransmitter
Down
- 1. A mental or psychological scene or area of the imagination
- 3. A neurotransmitter often contributing with feelings of happiness
- 5. Awake
- 6. A feeling of worry
- 8. A series of thoughts and images during sleep