AP Psychology: Chapter 5 Sensation

Transduction

Conversion of one form of energy into another. In sensation, the transforming of stimulus energies into neural impulses. Ex:

Signal Detection Theory

A theory predicting how and when we detect the presence of a faint stimulus amid background stimulation. Assumes that there is no single absolute threshold and that detection depends partly on a person's experience, expectations, motivation, and level of fatigue. Ex: If i can tell how load a sound is in a room that would be signal detection.

Pitch

A tone's highness or lowness; depends on frequency. Ex: when someone sings they want to be on pitch while they are hitting the higher notes correctly.

Sensory Adaptation

Diminished sensitivity as a consequence of constant stimulation. Ex: When I am in a cold pool of water and slowly the water becomes neutral feeling I don't notice how cold it is anymore.

Sensorineural hearing loss

Hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerves; also called nerve deafness. Ex: If I listen to music incredibly loud in my ears will lose hearing progressively faster.

Conduction hearing loss

Hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea. Ex: I cant hear what people say in loud rooms due to the fact that I have lost the conduction of wavelengths to my cochlea.

Place Theory

In hearing, the theory that links the pitch we hear with the place where the cochlea's membrane is stimulated. Ex: If I clap with someone blind folded this is a process of using place theory of the hand clapping.

Frequency Theory

In hearing, the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch. Ex: When we hear a musical note our ears vibrate at different rates to create massive impulses that are impulse to the auditory nerve.

Cones

Receptor cells that we 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: When you squint you are focusing the image on the groupings of cones.

Rods

Retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond. Ex: While seeing I use the rods in my eye to perceive the black and white in the image I am seeing.

Psychophysics

The study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them. Ex: When looking at the image above you can tell the difference between the two faces one is slightly larger.

Pupil

The adjustable opening in the center of the eye through which light enters. Ex: The light that enters my eye is adjusted by the pupil.

Middle ear

The chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochlea's oval window. Ex: When I listen to people talking or music the sound waves travel through the middle ear to be processed.

Difference Threshold Theory

The minimum difference between two stimuli required for detection 50 percent of the time. We experience the difference threshold as a just noticeable difference. Ex: If I can pinpoint the difference between two frequencies 50 percent of the time.

Absolute Threshold

The minimum stimulation needed to detect a particular stimulus 50 percent of the time. Ex: This would be being able to detect the difference in the colors 50 percent of the time.

Frequency

The number of complete wavelengths that pass a point in a given time. Ex: we use frequency to decipher musical ballets.

Sensory interaction

The principle that one sense may influence another, as when the smell of food influences its taste. Ex: When I take cough medicine if I plug my nose I won't taste the medication as prominently.

Weber's Law

The principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount). Ex: In the two jars they are set differently to make one jars content look larger this is using weber's law.

Sensation

The process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment. Ex: Lighting a candle that smells like apple cinnamon and after a few minutes being able to smell it.

Parallel Processing

The processing of several aspects of a problem simultaneously; the brain's natural mode of information processing for many functions, including vision. Contrasts with the step-by-step (serial) processing of most computes and of conscious problem solving. Ex: When a person looks at an object they don't just see one part of the object it is perceived as a whole object.

Vestibular Sense

The sense of body movement and position, including the sense of balance. Ex: If I hurt my vestibular sense I would be falling left and right due to the fact that it is damaged.

Opponent process Theory

The theory that opposing retinal processes (red-green, yellow- blue, white-black) enable color vision. Ex: Cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green.

Young-Hemholtz Theory

The theory that the retina contains three different color receptors-one most sensitive to red, one to green, one to blue- which can produce the perception of any color. Ex: The theory that our retina picks up more reds, greens, and blues with the color receptor cones.

Gate-control theory

The theory that the spinal cord contains a neurological "gate" that blocks pain signals or allows them to pass on to the brain. The "gate" is opened by the activity of pain signals traveling up small nerve fibers and is closed by activity in larger fibers or by information coming from the brain. Ex: If I injured my back I would have signals sent to my brain through small fibers.

Cornea

The transparent layer forming the front of the eye. Ex: If you scratch your cornea it causes intense pain.

Lens

The transparent structure behind the pupil that changes shape to help focus images on the retina. Ex: To focus on an image my lens needs to shape to allow my retina to see the image clearly.