| Sensation and Perception |
definition and example |
| sensation | Is the process by which you detect physical energy from your enviroment and encode it as neural signals. EX-feeling a needle prick your finger. |
| perception | The process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events. EX-knowing that a needle pricking your finger is going to hurt. |
| bottom- up processing | Analysis that begins with the sensory receptors and works up to the brain's integration of sensory information. EX-gives us the ability to detect lines, angles, and colors in a painting |
| top- down processing | information processing guided by higher level mental processes, as when we construct perceptions drawing on our experience and expectations. EX-when looking at a painting, we pay attention to the aspects of the painting that will give observations meaning |
| absolute threshold | the minimum stimulation necessary to detect a senses 50 percent of the time. EX-detecting light, sound, pressure, taste, or odor |
| signal detection theory | predicts when we will detect weak signals EX- measured as our ratio of "hits" to "false alarms" |
| subliminal | below the threshold. EX- being able to taste an ounce of salt in a 2 liter of juice. |
| difference threshold | This is also called the "just noticeable difference." It is the minimum difference a person can detect between any 2 stimuli 50% of the time. EX-Parents can detect their child's cry among other children's cries |
| Weber's Law | The principle that, to be perceived as different, 2 stimuli must differ by a constant minimum percentage (rather than a constant amount) EX-If the price of a $1 chocolate bar goes up by 10 cents, shoppers might notice the change |
| sensory adaptation | diminished sensitivity as a consequence of constant stimulation. EX-If you are listening to your radio on a set volume for an hour, and someone comes along and turns the volume up by only 2 levels, you will probably not notice the difference |
| transduction | conversion of one form of energy into another. EX-Transforming sights or wounds into neural impulses our brain can interpret. |
| rods | retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond. EX-movie theater/ shadows |
| cones | retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well- lit conditions. The cones detect fine detail and give rise to color sensations EX-sunny, spring day |
| photoreceptors | convert light energy to electrochemical neural impulses. EX-Both rods and cones are the photoreceptors |
| dark adaptation | results from a shift from predominantly cone vision to predominantly rod vision. EX-sudden darkness |
| audition | the sense or act of hearing EX- listening |
| amplitude | the greater the composition, the larger the height of the sound wave and the louder the sound EX-dicibels |
| sound localization | the process by which you determine the location of a sound EX- If your friend calls to you from your left side, your left ear hears a louder sound than your right ear |
| frequency theory | the rate of the neural impulses traveling up the auditory nerve matches the frequency of a tone, enabling you to sense its pitch EX-When tuning an instrument...you listen to a device that produces the tone, and then being able to match it with your pitch |
| conduction deafness | is a loss of hearing that results when the eardrum is punctured or any of the ossicles lose their ability to vibrate EX-When hearing aids only help some people. |
| nerve deafness | results from damage to the cochlea, hair cells, or auditory neurons EX-a convential hearing aid being able to restore hearing by amplifying vibrations |
| somatosensation | is a general term for 4 classes of tactile sensations: touch/ pressure, warmth, cold, and pain |
| kinesthesis | is the system that enables you to sense the position and movement of individual parts of your body EX-Nerve endings in your muscles, tendons, and joints |
| vestibular sense | is your sense of equilibrium or body orientation |
| gustation | taste |
| olfaction | smell |
| optical/ visual illusions | are discrepancies between the appearance of a visual stimulus and its physical reality EX-Reversible figures |
| monocular cues | are clues about distance based on the image of one eye |
| binocular cues | are clues about distance requiring two eyes |
| depth perception | is the ability to judge the distance of objects EX-Being able to judge how far a car is away from you when driving |
| schemas | are concepts or frameworks that organize and interpret information EX-Can account for people's interpretations of UFOs |
| ESP | is the controversial clain that perception can occur apart from sensory input |
| parapsychology | the study of paranormal events EX- telepathy, precognition, telekinesis |
