2.  Transduction – the process by which the sensory system encode stimulus energy as neural messages  Light Energy  The eyes do not detect “color,” but a spectrum of electromagnetic radiation  Humans have a limited spectrum; certain animals can only see ultraviolet light, which humans cannot detect  Two characteristics of light:  Wavelength (determines the “hue” or color we see)  Intensity (determines brightness)

3.  Nearsightedness  Caused by a misshapen eyeball which focuses the light rays in front of the retina  Close objects are clearer; far away objects are blurry  Farsightedness  Caused by misshapen eyeball which produces a focused image behind the retina  Close objects are blurry; far away objects are clearer

4.  Young-Helmholtz trichromatic theory  States that the retina has 3 types of color receptors – red, green, or blue  Color blindness  People with this condition can see color – they simply lack functioning red or green –sensitive cones or both.  This may hinder an individual from obtaining certain jobs that involve radars with red and/or green images (military, pilots, etc.)  Opponent –process theory: states that opposing retinal processes enable color vision (i.e. red- green, yellow-blue, white-black

5.  The strength of sound waves  determines loudness  Length of sound waves  determines frequency  Frequency  determines pitch (high or low)  Sound energy is measured in decibels

6.  Place theory: states that we hear different pitches based on different sound waves that trigger activity at different places along the cochlea’s basilar membrane  Frequency theory: states that we detect pitch because the basilar membrane vibrates with the incoming sound wave

7.  Conduction hearing loss - caused by the problems with the mechanical system that conducts sound waves to the cochlea  Ex: ear drum is punctured OR middle ear loses the ability to vibrate  Sensorineural hearing loss – caused by damage to the cochlea’s hair cell receptors or associated nerves (nerve deafness)  Ex: heredity, aging, prolonged loud noise or music

8.  Skin covers your organs and allows a variety of four distinct skin senses:  Pressure  Warmth  Coldness  Pain  Gate-control theory – states that the spinal cord contains a neurological “gate” that either blocks pain signals or allows them to pass on to the brain  Therapies for pain control:  Drugs  Surgery  Acupuncture  Electrical stimulation

9.  Taste is a chemical sense  Four taste sensations:  Sweet  Sour  Salty  Sweet  Researchers have “discovered” a FIFTH taste sensor: “Umami” which gives the ability to taste meats

10.  Linda Bartoshuk (1993) discovered the following taste facts:  Our emotional responses to taste are hard-wired  People without tongues can still taste through receptors on the back and roof of the mouth  If you lose taste sensation on one side of your tongue, the other side will become more sensitive to taste. You won’t notice the difference.  We can neither taste nor smell most nutrients – fat, protein, starch, and food vitamins

11.  Smell is a chemical sense.  Sensory organ is called the olfactory nerve  Sense of smell is critical in the bonding of infant to mother  The ability to identify scents peaks in early adulthood and gradually declines as one ages  Each individual has his/her own body chemical odor

12.  The sense of our body parts’ position and movement  Involves joints, muscles, tendons, and sense of balance  Vestibular sense: monitors the head and body’s position and movement  Semicircular canals – looks like a 3-dimensional pretzel in your inner ear  Vestibular sacs - contains fluid to maintain a sense of balance

13. The process of organizing and interpreting information, enabling us to recognize meaningful objects and events.

29. If the sounds do not work click here for link.

30.  The smallest amount of a stimuli we can detect about half of the time.

31.  Stimuli below our absolute threshold.  Backmasking  25 th frame  Do Subliminal Messages work?  Probably a placebo effect Do you hear "Now he uses marijuana.“? Do you hear “Ah, see me. I'm not too young”? Do you hear Pass the gun now. It kills the love, the love is cold”? Do you hear"Play backwards. Hear words sung.“?

32. The smallest amount of change needed to detect in a stimulus before we detect a change.

33.  Computes the Just Noticeable Difference.  The change needed is proportional to the original intensity of the stimulus.  The more intense the stimulus the more change is needed to notice the difference.  8% for vision.

35.  Absolute thresholds are not really absolute.  Things like motivation or physical state can effect what we sense.  False Positives  False Negatives My wife could sleep through a war, but if one of our sons even whimpers, she is up!!!

36.  We perceive by filling the gaps in what we sense.  I _ant ch_co_ate ic_ cr_am.  Based on our experiences and schemas.  If you see many old men in glasses, you are more apt to process a picture of an old man (even when you may be in error).

37.  Also called feature analysis.  We use the features on the object itself to build a perception.  Takes longer that top-down but is more accurate. Click to see an example of bottom –up processing.

38. Our first perceptual decision is what is the image is the figure and what is the background.

39.  Gestalt psychologists focused on how we GROUP objects together.  We innately look at things in groups and not as isolated elements.  Proximity (group objects that are close together as being part of same group)  Similarity (objects similar in appearance are perceived as being part of same group)  Continuity (objects that form a continuous form are perceived as same group)  Closure (like top-down processing…we fill gaps in if we can recognize it)

40.  Objects change in our eyes constantly as we or they move….but we are able to maintain content perception  Shape Constancy  Size Constancy  Brightness Constancy

41.  Stroboscopic effect (flip book effect)  Phi phenomenon  Autokinetic Effect (if people stare at a white spotlight in a dark room, it appears to move.)

42.  Eleanor Gibson and her Visual Cliff Experiment.  If you are old enough to crawl, you are old enough to see depth perception.  We see depth by using two cues that researchers have put in two categories:  Monocular Cues  Binocular Cues

43.  You really only need one eye to use these (used in art classes to show depth).  Linear Perspective  Interposition  Relative size  Texture gradient  Shadowing

44.  We need both of our eyes to use these cues.  Retinal Disparity (as an object comes closer to us, the differences in images between our eyes becomes greater.  Convergence (as an object comes closer our eyes have to come together to keep focused on the object).