Studied by 61 Peoplesensation
Tags & Description
sensation
The process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment.
sensory receptors
sensory nerve endings that respond to stimuli
perception
The process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events
bottom-up processing
Analysis that begins with the sensory receptors and works up to the brains, Integration of sensory information.(things we do not know; we build this information from the bottom up)
top-down processing
information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations (recognition)
transduction
conversion of one form of energy to another. In sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brain can interpret
What do all our senses do?
they all receives sensory stimulation, often using specialized receptor cells, transform the simulation into neural impulses, and delivered a neural information to our brain.
psychophysics
The study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them. For example, light is brightness and sound is volume.
absolute threshold
The minimum stimulus energy needed to detect a particular stimulus 50% of the time.
What’s the rough distinction from sensation and perception?
sensation is the bottom-up process by which your sensory receptors and nervous system receive and represent stimuli. Perception is the top-down process by which your brain creates meaning by organizing and interpreting what your senses detect.
Single detection theory
A theory predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise). Assumes there is no single absolute threshold, and that the detection depends, partially on a persons experience, expectations, motivation, and alertness. Explains why absolute threshold varies
subliminal
below one's absolute threshold for conscious awareness
priming
The activation, often unconsciously, of certain associations, thus predisposing one’s perception, memory, or response.
difference threshold
The minimum difference between two stimuli required for your detection 50% of the time. We experience the difference threshold as a noticeable difference (or jnd). For example, the smallest difference in sound for us to perceive a change in the radio's volume.
JND is determined by what two factors?
how much of a stimulus was there to begin with and which sense is being stimulated.
weber’s law
The principle that, to be perceived, as different, to stimuli, must differ by a constant minimum percentage (rather than a constant amount)
can we be persuaded by subliminal stimuli (audio and video messages) ? To lose weight, stop smoking, etc.
results from 16 experiment showed no powerful, and during influences on behavior. Not one of the recordings helped more than a possible, which works only because we believe it will.
using sound as example, explain how these concepts differ: absolute threshold, subliminal, stimulation, and difference threshold
Absolute threshold is the minimum simulation needed to detect a particular sound, (such as an approaching bike on the sidewalk behind you) 50% of the time. Subliminal stimulation happens when, without your awareness, you are sensory system processes, a sound that is below your absolute threshold. A difference threshold is the minimum difference meaning to distinguish between to stimuli (such as between the sound of a bike, and the sound of a runner coming up behind you)
Sensory adaptation
diminish sensitivity as a consequence of constant stimulation. (For example, noticing a foul odor but feeling less disgusted as you get used to it)
perceptual set
A mental predisposition to perceive one thing and not another. For example, a driver will focus on other cars and things that might affect their safety.
what does perceptual set affect?
it affects top down processing, what we hear, taste, feel, and see
“Our immediate ____, and the ______ and _______ we bring to a situation, also affect our interpretations.”
context, motivation, emotion
sensation is to ______ as perception is to______
bottom-up processing; top-down processing
another term for “difference threshold” is the ____ ________ _________.
just noticeable difference
what does sensory adaptation help us focus on ?
important changes in the environment
our perceptual set influences what we perceive. This mental tendency reflects our ______, _______, and _________.
experiences; assumptions; expectations
transduction
the transformation of stimulus energy (sights, sounds, and smells) into neural impulses
wavelength
The distance from the peak of one light or sound wave to the peak of the next. Electromagnetic wavelengths vary from the short blips of gamma rays to the long pulses of radio transmission
hue
The dimension of color that is determined by the wavelength of light; but we know as the color names, blue, green, and so forth.
intensity
The amount of energy in a light wave, or a sound wave, which influences what we perceive as brightness or loudness. Intensity is determined by the amplitude of the wave (height)
Lens
The transparent structure behind the pupil that changes shape to focus images on the retina
Retina
The light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information
accommodation
The process by which the eyes lens changes shape to focus near or far objects on the retina
rods
retinal receptors, that detect black, white, and gray, and are sensitive to movement; necessary for peripheral and twilight vision, when cones don’t respond
cones
retinal receptors that are concentrated near the center of the retina that function in daylight or in well-lit conditions. Cones detect fine detail and give rise to color sensations.
bipolar cells
receives messages from photo receptors and transmit them to ganglion cells, which converge to form to optic nerve
optic nerve
The nerve that carries neural impulses from the eye to the brain
blindspot
The point at which the optic nerve leaves the eye, creating a blind spot because no receptor cells are located there
fovea
The central focal point in the retina, around with the eye’s cones cluster
Some nocturnal animals, such as toads, mice, rats, and bats, have impressive night vision thanks to having many more (rods/cones) than (rods/cones) in their retinas. These creatures probably have very (color/black-and-white) vision.
rods; cones; color
Cats are able to open their _______ much wider than we can, which allows more light into their eyes so they can see better at night.
pupils
if no one sees a tomato, is it red?
No, the tomato is anything BUT red, because it rejects (reflects) the long wave lengths of red. The tomato’s color is our mental construction, our perception of color resides not on the object itself but in the theater of our brain, as illustrated by our dreaming in color
Young-Helmholtz trichromatic (three color) theory
The theory that the retina contains three different types of color receptors-one most sensitive to red, one to green, one to blue-which, when stimulated and combination, can produce the perception of any color
how does the optic nerve connect to the brain?
The optic nerve connects to the thalamus in the middle of the brain, and the thalamus connects to the visual cortex.
blind sight
A phenomenon in which patients with damage in the primary visual cortex of the brain can tell where an object is although they claim they cannot see it.
opponent-process theory
The theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision. For example, some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green.
what would this flag look like after looking at it for a minute then looking away?
the yellow will become blue, green into red, and black into white.
what is the current theory of color processing?
That it happens in two stages,
The retina's red, green, and blue cones respond in varying degrees to different color stimuli, as the Young Helmholtz trichromatic theory suggested.
The cones' responses are then processed by opponent-process cells, as Hering's opponent-process theory proposed.
feature detectors
nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement
