Ch 4 Sensation And Perception Flashcards
(120 cards)
What are psychophysics?
The study of how physical stimuli are translated into psychological experience
What is the difference between sensation and perception?
Sensation is the stimulation of sense organs
Perception is the selection, organization, and interpretation of sensory output
What is a threshold?
A dividing point between energy levels that do and do not have a detectable effect- difference threshold
Ie. Turning music up and down till you notice a difference
What is an absolute threshold?
The minimum amount of stimulation that an organism can detect 0—> something
True or false, for an absolute threshold to exist, it must occur 50% of the time
True
What is a just noticeable difference?
The smallest difference in the amount of stimulation that a specific sense can detect.
Eg. Smallest amount of salt you can add to notice difference
True or false, an absolute threshold is the just noticeable difference from nothing
True
Explain the signal detection theory
Proposes that he detection of stimuli involves decision processes as well as sensory processes influenced by a variety of factors
Explain sensory adaptation
A gradual decline in sensitivity due to prolonged stimulation
Eg. Smelly garbage
The smallest amount of tumult ion you can detect is (0—>something)
Absolute threshold
Light waves vary in amplitude, wavelength and purity. Explain what amplitude, wavelength, and purity are.
Amplitude– height
Wavelength– distance between peaks
Purity– how aired the mix of light is
True or false, humans can only perceive the wavelengths of light?
True
what are the two functions of the eye?
to channel light into the neural tissue, and to house that tissue
When referring to the eye, what is the lens?
Transparent eye structure that focuses the light rays falling on the retina
What is the difference between nearsightedness and farsightedness?
nearsightedness– close objects seen clear, far objects seem blurry
farsightedness– far objects seen clear, close objects are seen blurry
When does nearsightedness occur? When does farsightedness occur? What is “wrong” with the eye?
When the cornea bends the light too much (nearsightedness)
When the eyeball is too short
farsightedness
what are saccades?
When the eyes are scanning an environment and making brief fixations
What is the retina?
The neural tissue lining the inside back surface of the eye
What does the retina do?
absorbs light, processes images, and sends visual info to the brain
In the retina, what are the differences of the cones and the rods?
cones– specialized visual receptors that play key roles in daylight vision and colour vision.
Rods– specialized visual receptors that play a key role in night vision and peripheral vision
True or false, the rods and cones on the retina funnel signals to the receptive field
true
What is the receptive field?
he retinal area that when stimulated affects the firing of that cell (for example, the signal towards the brain and nearby cells)
What is lateral antagonism and when does it occur?
occurs when neural activity in a cell opposes activity in surrounding cells , when the excited neuron reduced activity of its neighbours
What is the fovea? (in the retina)
tiny spot in the center of the retina that contains only cones– visual acuity is best here