The Ear Dr. Fred Hossler/ Visuals Unlimited Preview Question 9: How does the ear transform sound energy into neural messages?

The Ear Outer Ear: Collects and sends sounds to the eardrum. Middle Ear: Chamber between eardrum and cochlea containing three tiny bones (hammer, anvil, stirrup) that concentrate the vibrations of the eardrum on the cochlea’s oval window. Inner Ear: Innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs.

Cochlea Cochlea: Coiled, bony, fluid-filled tube in the inner ear that transforms sound vibrations to auditory signals.

Hearing clip

Theories of Hearing Place Theory= pitch is determined by the location of greatest vibration on the basilar membrane; high pitch Frequency Theory= pitch is determined by the frequency with which hair cells in the cochlea fire; low pitch With age, hearing acuity declines (but deafness is not) Surgery & digital technology

Smell Most primitive sense

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

Smell Like taste, smell is a chemical sense. Odorants enter the nasal cavity to stimulate 5 million receptors to sense smell. Unlike taste, there are many different forms of smell. Preview Question 15: How do we experience smell?

Smell Our sense of smell is activated by complex protein called Odorant binding protein (OBP), produced in the nasal gland. Olfactory bulb= the smell center of the brain Women generally have a better sense of smell than men Sharpest during the early adult years (20 yr. – 40 yr). Pheromones= communicating molecules

Taste Varies culture to culture because we are omnivores (eat everything) Flavor is a combination of taste and smell

Taste (cont). Taste buds= structures on the tongue that contain receptor cells for taste Papillae= small bumps on the tongue that contain taste buds.

Taste Traditionally, taste sensations consisted of sweet, salty, sour, and bitter tastes. Recently, receptors for a fifth taste have been discovered called “Umami”. Identify taste within 1/10 of second Preview Question 14: How do we experience taste? Sweet Sour Salty Bitter Umami (MSG)

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

Skin is our largest sense organ! Touch The sense of touch is a mix of four distinct skin senses—pressure, warmth, cold, and pain. Skin is our largest sense organ! Preview Question 13: How do we sense touch and sense our body’s position and movement? How do we experience pain? Bruce Ayers/ Stone/ Getty Images

Skin Senses Only pressure has identifiable receptors. All other skin sensations are variations of pressure, warmth, cold and pain. Pressure Vibration Vibration Burning hot Cold, warmth and pain

http://education-portal.com/academy/lesson/taste-touch-and-smell.html

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

Biopsychosocial Influences

Gate-Control Theory Melzack 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

Pain Control Pain can be controlled by a number of therapies including, drugs, surgery, acupuncture, exercise, hypnosis, and even thought distraction. Placebo effect Positive thinking Todd Richards and Aric Vills, U.W. ©Hunter Hoffman, www.vrpain.com

Perception It takes place in the brain Using sensory information as raw material, the brain creates perceptual experiences that go beyond what we sense directly.

Form Perception Organization of the visual field into objects (figures) that stand out from their surroundings (ground). Preview Question 17: How do figure-ground and grouping principles contribute to our perceptions? Time Savings Suggestion, © 2003 Roger Sheperd.

Grouping After distinguishing the figure from the ground, our perception needs to organize the figure into a meaningful form using grouping rules.

Perceptual Constancy Perceiving objects as unchanging even as illumination and retinal images change. Preview Question 20: How do perceptual constancies help us to organize our sensations into meaningful perceptions?

Color Constancy Perceiving familiar objects as having consistent color even when changing illumination filters the light reflected by the object. Color Constancy

Size-Distance Relationship The distant monster (below, left) and the top red bar (below, right) appear bigger because of distance cues. Alan Choisnet/ The Image Bank From Shepard, 1990

Size-Distance Relationship Both girls in the room are of similar height. However, we perceive them to be of different heights as they stand in the two corners of the room. Both photos from S. Schwartzenberg/ The Exploratorium

Ames room clip

Distance and Depth Perception The ability to judge distance and depth is critically important if an organism is to move freely in its environment. Monocular cue = visual cues requiring the use of one eye Binocular cue= visual cues requiring the use of both eyes

Monocular Cues Linear perspective= two parallel lines that extend into the distance appear to come together at a point in the horizon

Monocular Cues Texture gradient = an object that is close also seems to have a rough or detailed texture

Binocular Cues Retinal disparity: Images from the two eyes differ. Try looking at your two index fingers when pointing them towards each other half an inch apart and about 5 inches directly in front of your eyes. You will see a “finger sausage” as shown in the inset.

Locating Sounds Monaural cue= require one ear Binaural cue= both ears

Perceiving movement Both visual information from the retina and messages from the muscles around the eyes as they follow the object. Real Movement= physical displacement of an object In relation to the background which is perceived as stationary Apparent Movement= perceive movement when object is standing still (autokinetic illusion)

Perceiving movement Stroboscopic movement= rapid series of still images

Perceiving movement Phi Phenomenon = apparent movement caused by flashing lights in sequences (theater marquee)

Visual Illusions Illusions are misleading cues in stimuli that give rise to inaccurate or impossible perceptions

Perceptual Interpretation (cont). Motivation Values Expectations Cognitive Style Experience and Culture Personality

Review Game http://www.uni.edu/walsh/jeopardy.htm