Across
- 4. nerve cells in the brain's visual cortex that respond to specific features of the stimulus, such as shape, angle, or movement.
- 5. the controversial claim that perception can occur apart from sensory input; includes telepathy, clairvoyance, and precognition.
- 7. the adjustable opening in the center of the eye through which light enters.
- 13. the central focal point in the retina, around which the eye's cones cluster.
- 15. the eye's clear, protective outer layer, covering the pupil and iris.
- 16. below one's absolute threshold for conscious awareness.
- 18. analysis that begins with the sensory receptors and works up the brain's integration of sensory information.
- 19. from our environment.
- 20. the study of paranormal phenomena, including ESP and psychokinesis.
- 22. the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events.
- 25. the study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them.
- 26. the dimension of color that is determined by the wavelength of light; what we know as the color names blue, green, and so forth.
- 28. diminished sensitivity as a consequence of constant stimulation.
- 29. the process by which our sensory receptors and nervous system receive and represent stimulus
- 32. the theory that the retina contains three different types of color receptors one most sensitive to red, one to green, one to blue-which, when stimulated in combination, can produce the perception of any color.
- 33. information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations.
- 35. the process by which the eye's lens changes shape to focus near or far objects on the retina.
- 36. the transparent structure behind the pupil that changes shape to help focus images on the retina.
- 37. the minimum difference between two stimuli required for detection 50 percent of the time.
Down
- 1. the distance from the peak of one light or sound wave to the peak of the next. Electromagnetic wavelengths vary from the short blips of gamma rays to the long pulses of radio transmission.
- 2. retinal receptors that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. Cones detect fine detail and give rise to color sensations.
- 3. the light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information.
- 6. the focusing of conscious awareness on a particular stimulus.
- 8. failing to see visible objects when our attention is directed elsewhere.
- 9. failing to notice changes in the environment.
- 10. the minimum stimulus energy needed to detect a particular stimulus 50 percent of the time.
- 11. processing many aspects of a problem simultaneously; the brain's natural mode of information processing for many functions, including vision.
- 12. the point at which the optic nerve leaves the eye, creating a "blind" spot because no receptor cells are located there.
- 14. the amount of energy in a light wave or sound wave, which influences what we perceive as brightness or loudness. Intensity is determined by the wave's amplitude (height).
- 17. a ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening.
- 21. the theory that opposing retinal processes enable color vision.
- 23. retinal receptors that detect black, white, and grey, and are sensitive to movement; necessary for peripheral and twilight vision, when cones don't respond.
- 24. a theory predicting how and when we detect the presence of a faint stimulus amid background stimulation. Assumes there is no single absolute threshold and that detection depends partly on a person's experience, expectations, motivation, and alertness.
- 27. the nerve that carries neural impulses from the eye to the brain.
- 29. sensory nerve endings that respond to stimuli.
- 30. conversion of one form of energy into another. In sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brain can interpret.
- 31. the principle that to be perceived as different, two stimuli must differ by a constant minimum percentage.
- 34. the activation, often unconsciously, of certain associations, thus predisposing one's perception, memory, or response.