Sensation

1. Sensation Sensation: Receiving. Perception: Interpreting.

2. Sensation--Thresholds Absolute Threshold minimum stimulation needed to detect a particular stimulus 50% of the time Subliminal below one�s absolute threshold for conscious awareness Difference Threshold the minimum difference that a person can detect between two stimuli 50 percent of the time we experience the difference threshold as a just noticeable difference (jnd)

3. Sensation--Thresholds When stimuli are detectable less than 50% of the time (below one�s absolute threshold) they are �subliminal�

4. Vision Rods retinal receptors that detect black, white, and gray necessary for peripheral and twilight vision Cones receptor cells that are concentrated near the center of retina function in daylight or well-lit conditions detect fine detail and give rise to color sensation

5. The Eye Optic Nerve: nerve that carries neural impulses from the eye to the brain Blind Spot: point at which the optic nerve leaves the eye, creating a �blind spot� because there are no receptor cells located there

6. Vision--Receptors

7. Visual Information Processing Parallel Processing processing several aspects of a problem simultaneously the brain�s natural mode of information processing for many functions, including vision

8. Visual Information Processing

9. Color-Deficient Vision People who suffer red-green blindness have trouble perceiving the number within the design

10. Color Depends on Context

11. Audition Visual Capture- tendency for vision to dominate the other senses Audition- the sense of hearing Frequency- the number of complete wavelengths that pass a point in a given time Pitch- a tone�s highness or lowness depends on frequency

12. Audition--The Ear Middle Ear the chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, stirrup) that concentrate the vibrations of the eardrum on the cochlea�s oval window

13. Audition--The Ear Inner Ear innermost part of ear, containing the cochlea, semicircular canals and vestibular sacs Cochlea coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses

14. The Intensity of Some Common Sounds

15. Audition--The Ear

16. Touch Skin Sensations pressure only skin sensation with identifiable receptors warmth cold pain

17. Pain Gate-Control Theory theory that the spinal cord contains a neurological �gate� that blocks pain signals or allows them to pass on to the brain �gate� opened by the activity of pain signals traveling up small nerve fibers �gate� closed by activity in larger fibers or by information coming from the brain

18. Taste Taste Sensations sweet sour salty bitter Sensory Interaction the principle that one sense may influence another as when the smell of food influences its taste

19. Smell

20. Body Position and Movement Kinesthesis the system for sensing the position and movement of individual body parts

21. Perceptual Organization Gestalt an organized whole tendency to integrate pieces of information into meaningful wholes

23. Perceptual Organization- Gestalt Grouping the perceptual tendency to organize stimuli into coherent groups Grouping Principles proximity-group nearby figures together similarity-group figures that are similar continuity- perceive continuous patterns closure-fill in gaps connectedness-spots, lines and areas are seen as unit when connected

24. Perceptual Organization- Gestalt

25. Perceptual Organization-Depth Perception Depth Perception ability to see objects in three dimensions allows us to judge distance Binocular cues- depend on use of two eyes retinal disparity images from the two eyes differ closer the object, the larger the disparity convergence neuromuscular cue two eyes move inward for near objects

26. Perceptual Organization-Depth Perception Monocular Cues-available to either eye alone relative size smaller image is more distant interposition closer object blocks distant object relative clarity hazy object seen as more distant texture coarse --> close fine --> distant

27. Perceptual Organization-Depth Perception

28. Perceptual Organization-Depth Perception Monocular Cues (continued) relative height higher objects seen as more distant relative motion closer objects seem to move faster linear perspective parallel lines converge with distance relative brightness closer objects appear brighter

29. Perceptual Constancy Perceptual Constancy perceiving objects as unchanging despite changes in retinal image color shape size

30. Perceptual Organization

31. Perceptual Organization-M�ller-Lyer Illusion

32. Perceptual Organization- Size-Distance Relationship

33. Perceptual Organization-Brightness Contrast

34. Perceptual Interpretation Perceptual Adaptation (vision) ability to adjust to an artificially displaced visual field prism glasses Perceptual Set a mental predisposition to perceive one thing and not another

35. Perceptual Set- Human Factors

36. Is There Extrasensory Perception? Extrasensory Perception controversial claim that perception can occur apart from sensory input telepathy clairvoyance precognition Parapsychology the study of paranormal phenomena ESP psychokinesis