1 Other Important Senses  Touch  Taste  Smell  Body Position and Movement

2 Other Important Senses Sense of touch is a mix of four distinct skin senses- pressure, warmth, cold, and pain. Bruce Ayers/ Stone/ Getty Images

3 Skin Senses Only pressure has identifiable receptors, all other skin sensations are variations of pressures, warmth, cold and pain. Burning hot PressureVibration Cold, warmth and pain

4 Pain Pain tells the body that something has gone wrong. Usually pain results from damage to the skin and other tissues. There is a rare disease in which the person feels no pain. Ashley Blocker (right) feels neither pain nor extreme hot or cold. AP Photo/ Stephen Morton

5 Biopsychosocial Influences

6 Gate-Control Theory Melzak and Wall (1965, 1983) proposed that our spinal cord contains neurological “gates” that either block pain or allow it to be sensed. Gary Comer/ PhototakeUSA.com

7 Pain Control Pain can be controlled by a number of therapies including, drugs, surgery, acupuncture, exercise, hypnosis and even thought distraction. Todd Richards and Aric Vills, U.W. ©Hunter Hoffman,

8 Taste Traditionally taste sensations consisted of sweet, salty, sour and bitter tastes. Recently receptors for a fifth taste have been discovered called “Umami”. Sweet Sour Salty BitterUmami (Fresh Chicken)

9 Sensory Interaction When one sense affects another sense sensory interaction takes place. So the taste of strawberry interacts with its smell and its texture on the tongue to produce flavor.

10 Smell Like taste smell is a chemical sense. Odorants enter the nasal cavity to stimulate 5 millions receptors to sense smell. Unlike taste there are many different forms of smells.

11 Age, Gender and Smell Ability to identify smell peaks during early adulthood but steadily decline after that. Women are better at detecting odors than men.

12 Smell and Memories Brain region (red) for smell is closely connected with brain regions (limbic system) involved with memory, that is why strong memories are made through the sense of smell.

13 Body Position and Movement The sense of our body parts’ position and movement is called kinesthesis. And the vestibular sense monitors the head (and body’s) position. Whirling Dervishes Wire Walk Bob Daemmrich/ The Image Works

14 Perceptual Organization  Perceptual Illusions  Form Perception  Motion Perception  Perceptual Constancy

15 Perceptual Illusions To understand how perception is organized, illusions provide good examples. It is as good to study faulty perception as other perceptual phenomena. Line AB is longer than line BC.

16 Tall Arch Vertical dimension of the arch looks longer than the horizontal dimension when both are equal. Rick Friedman/ Black Star

17 Illusion of a Worm Figure on the right gives us the illusion of a blue hazy “worm” when it is nothing else but blue lines identical to the picture on the left. © 1981, by permission of Christoph Redies and Lothar Spillmann and Pion Limited, London

18 3-D Illusion To perceive this figure in two dimensions takes a great deal of effort. Reprinted with kind permission of Elsevier Science-NL. Adapted from Hoffman, D. & Richards, W. Parts of recognition. Cognition, 63, 29-78

19 Perceptual Organization When vision competes with other senses vision usually wins – a phenomenon called visual capture. How do we form meaningful perceptions from sensory information? We organize it. Gestalt psychologists showed that a figure formed a “whole” different than its surroundings.

20 Organization of the visual field into objects (figures) that stand out from their surroundings (ground). Form Perception Time Savings Suggestion, © 2003 Roger Sheperd.

21 Grouping Having discriminated figure from ground our perception needs to organize figure into meaningful form using grouping rules.

22 Grouping & Reality Usually grouping principles help us construct reality but at times lead us astray. Both photos by Walter Wick. Reprinted from GAMES Magazine..© 1983 PCS Games Limited Partnership

23 Depth Perception Visual Cliff Depth perception enables us to judge distances. Gibson and Walk (1960) suggested that human infants (crawling age) have depth perception. Even new born animals show depth perception. Innervisions

24 Binocular Cues Retinal disparity: Images from the two eyes differ. Try looking at your two fingers half an inch apart about 5 inches away. You will see a “finger sausage” as shown in the inset.

25 Binocular Cues Convergence: Neuromuscular cues. When two eyes move inward (towards the nose) to see near objects, and outward (away from the nose) to see far away objects.

26 Monocular Cues Relative Size: If two objects are similar in size, we perceive one that casts a smaller retinal image as farther away.

27 Monocular Cues Interposition: Objects that occlude (block) other objects tend to be perceived as closer. Rene Magritte, The Blank Signature, oil on canvas, National Gallery of Art, Washington. Collection of Mr. and Mrs. Paul Mellon. Photo by Richard Carafelli.

28 Monocular Cues Relative Clarity: Because light form distant objects passes through more air, we perceive hazy objects as farther away than sharp clear objects.

29 Monocular Cues Texture Gradient: Indistinct (fine) texture signals increasing distance. © Eric Lessing/ Art Resource, NY

30 Monocular Cues Relative Height: We perceive objects higher in our field of vision as farther away. Image courtesy of Shaun P. Vecera, Ph. D., adapted from stimuli that appered in Vecrera et al., 2002

31 Monocular Cues Relative motion: Objects closer to a fixation point move faster and in opposing direction to objects farther away from a fixation point, which move slower and in the same direction.

32 Monocular Cues Linear Perspective: Parallel lines like rail road tracks, appear to converge with distance. The more the lines converge, the greater their perceived distance. © The New Yorker Collection, 2002, Jack Ziegler from cartoonbank.com. All rights reserved.

33 Monocular Cues Light and Shadow: Nearby objects reflect more light to our eyes. Given two identical objects, the dimmer one seems further away. From “Perceiving Shape From Shading” by Vilayaur S. Ramachandran. © 1988 by Scientific American, Inc. All rights reserved.

34 Motion Perception Motion Perception: Objects that tend to travel towards us grow in size and ones that move away shrink in size. The same is true when the observer moves to or from an object.