Across
- 2. the process by which an organism becomes more sensitive to stimuli
- 4. helps produce and feeling of relaxation
- 6. a regular sequence of the biological process that occurs every 24 hours
- 7. a drug that reduces neural activity and slow's the body activity
- 8. chemical messenger
- 10. is a system that gives information about the biological process
- 11. part of the retina that contains no photoreceptors
- 12. a drug that increases neural activity and speeds up body functions
- 13. building blocks of the nervous system
- 15. a psychedelic drug
- 17. stage of sleep identified by the random movement of the eyes
- 19. is a condition where people are highly
- 20. minimum difference detected between stimuli
Down
- 1. organizing and interpreting sensory info
- 3. type of stimulant often used to stay awake or to reduce appetite
- 5. sensory information to the brain
- 8. type of dry that dulls the senses, relives pain, and induces sleep
- 9. smallest amount of stimulus detected
- 14. photoreceptor cells that can function in less intense light
- 16. responsible for color vision and eye color sensitivity
- 18. and are in a trance