Sensation and Perception

Flashcards related to sensation and perception

Prosopagnosia

Difficulty recognizing faces.

Sensation

The ability to see, hear, touch, taste, and smell.

Perception

How we put the impulses received from our senses together so they make sense.

Bottom-up processing

Processing where our senses send information to our brain.

Top-down processing

Processing where our brain assembles the info to make sense of the impulses being sent to it.

Selective attention

The ability to screen out sensory information and focus on only a small portion of it.

Cocktail party effect

A person’s ability to single out one voice amidst many others, then to “change channels” to another voice.

Selective inattention or inattentional blindness

The ability to purposefully block out all but one bit of sensory input - to focus on one thing only.

Change blindness

Where people won’t notice a change in “scenery” after a brief interruption.

Choice blindness

People are unaware of the choices or preferences they make.

Choice blindness blindness

They can’t see that they’re choice blind.

Pop-out

Something is noticeably different from the others and thus, pops out to the viewer.

Absolute threshold

The minimum stimulation needed to detect light, a sound, a pressure, taste or odor 50% of the time.

Signal detection theory

Predicting whether or not we detect a stimulus depends not only on the stimulus, but also on our experience, expectations, motivation, and alertness.

Subliminal stimulation (kin to “subliminal perception”)

Stimulation just below our level of consciousness.

Prime

A subliminal stimulus prepared people for a response to a second stimulus.

Difference threshold or just noticeable difference (JND)

The minimum difference between two stimuli that can be detected at least 50% of the time.

Weber’s Law

The difference between two stimuli must differ by a constant proportion, not necessarily a constant amount.

Sensory adaptation

A person’s diminishing sensitivity to a sensory stimulus. In other words, if a stimulus persists, you get used to it.

Transduction

The process where our eyes sense light energy and change it into neural messages that our brain can handle.

Cornea

The transparent protective coating over the front part of the eye.

Pupil

A small opening in the iris through which light enters the eye.

Iris

Colored part of the eye.

Lens

Transparent part of the eye inside the pupil that focuses light onto the retina.

Retina

The lining of the eye containing receptor cells that are sensitive to light. Transduction occurs here.

Receptor cell

Specialized cell that responds to a particular type of energy.

Rods

Receptor cells in the retina responsible for night vision and perception of brightness.

Cones

Receptor cells in the retina responsible for color vision.

Fovea

Area of the retina that is the center of the visual field.

Optic nerve

The bundle of axons of ganglion cells that carries neural messages from each eye to the brain.

Blind spot

Place on the retina where the axons of all the ganglion cells leave the eye and where there are no receptors.

Optic chiasm

Point near the base of the brain where some fibers in the optic nerve from each eye cross to the other side of the brain.

Trichromatic theory

Theory of color vision that holds that all color perception derives from three different color receptors in the retina.

Opponent-process theory

Theory of color vision that holds that three sets of color receptors respond in an either/or fashion to determine the color you experience.

Colorblindness

Partial or total inability to perceive hues.

Trichromats

People who have normal color vision.

Monochromats

People who are totally color blind.

Dichromats

People who are blind to either red- green or yellow-blue.

Amplitude

The height of the wave, which determines the loudness of the sound, measured in decibels.

Frequency

The number of cycles per second in a wave; in sound, it's the primary determinant of pitch.

Hertz (Hz)

Cycles per second; unit of measurement for the frequency of waves.

Pitch

Auditory experience corresponding primarily to frequency of sound vibrations, resulting in a higher or lower tone

Decibel

The magnitude of a wave; in sound the primary determinant of loudness of sounds

Ear canal

Also called the auditory canal, carries sound waves into the ear.

Eardrum

A membrane at the end of the auditory canal. It vibrates due to sound waves.

Hammer, anvil, stirrup

The three small bones in the middle ear that relay vibrations of the eardrum to the inner ear.

Oval window

Membrane across the opening between the middle ear and inner ear that conducts vibrations to the cochlea.

Round window

Membrane between the middle ear and inner ear that equalizes pressure in the inner ear.

Cochlea

Part of the inner ear containing fluid that vibrates which in turn causes the basilar membrane to vibrate.

Basilar membrane

Vibrating membrane in the cochlea of the inner ear; it contains sense receptors for sound.

Organ of Corti

Structure on the surface of the basilar membrane that contains the receptors cells for hearing.

Auditory nerve

The bundle of neurons that carries signals from each ear to the brain.

Place theory

Theory that pitch is determined by the location of the greatest vibration of the basilar membrane.

Frequency theory

Theory that pitch is determined by the frequency with which hair cells in the cochlea fire.

Conductive Hearing Loss

This occurs when sound vibrations from the tympanic membrane to the inner ear are blocked.

Sensorineural Hearing Loss

This occurs when there is damage to the vestibulocochlear (auditory) nerve.

Presbycusis

This occurs because of changes in the inner ear. This is a very common type of hearing loss that happens gradually in older age.

Tinnitus

People with tinnitus hear a constant ringing or roaring sound.

Kinesthesis

A person’s ability to know the position and movement of your body parts.

Vestibular sense

Monitor’s your head’s position and movement (therefore it also monitor’s your body’s position and movement).

Nociceptors

Detect harmful temperature, pressure, and chemicals.

Gate-control theory of pain

Says there is a “gate” in the spinal cord that switches pain on and off.

Endorphins

Nature’s pain- killer.

ESP, AKA “Extra Sensory Perception”

Belief that some people can sense things beyond our normal senses (sight, sound, etc.).

Gestalt

A whole sum of multiple parts.

Depth perception

The ability to see things in 3D which helps us gauge distance.

Binocular cues

While viewing close objects, we see things from slightly different angles.

Retinal disparity

Enables our brain’s to judge the distance of objects we’re looking at.

Relative height

Things seen higher up are perceived as farther away.

Relative size

Things small are perceived as farther away.

Interposition

When things are “stacked”, the one that’s covered up is farthest, the one that’s not covered is closest.

Linear perspective

Parallel lines, like railroad tracks, converge in the distance; the more they converge, the farther away.

Light and shadow

Close objects reflect more light, farther ones appear dimmer.

Relative motion

While we move, things close to us appear to move fast in the opposite direction; things farther away appear to move very slowly or not at all.

Stroboscopic effect

We perceive a series of still photos (like a film) as having continuous motion.

Phi phenomenon

Two lights flashing alternately gives the perception one light moving back-and-forth.

Shape constancy

Our tendency to expect things to retain their shape.

Size constancy

Our tendency to expect things to retain their size.

Lightness constancy

Our tendency to expect things to retain their lightness.

Color constancy

Our tendency to expect things to retain their color.

Perceptual adaptation

Our ability to adjust to changes in our sensations.

Perceptual set

What we’ve already seen and experienced (and thus expect) add up to what’s called a perceptual set.