Sensation vs. Perception Flashcards
Absolute threshold
The minimum of stimulus energy that is needed to activate a sensory system
Threshold of conscious percenption
The level of intensity that a stimulus must pass to be consciously perceived by the brain
Subliminal perception
Information received by CNS but does not cross threshold
Just noticeable difference
Minimum change in magnitude required for an observer to notice that two different stimuli are different
Discrimination testing
A participant is present with a stimulus. The stimulus is then changed slightly. The participant is asked to report if they perceive a change
Signal detection theory
Studies how internal and external factors influence thresholds of sensation and perception
Noise trial
signal presented
Catch trial
no signal presented
Hit
Signal present and subject perceives signal
Miss
Signal presented subject doesn’t perceive signal
False alarm
No signal presented but subject perceives signal
Correct negative
No signal present, subject identifies no signal was presented
Sclera
White of the eye
What is the function of the choroidal and retinal vessels
Blood vessels that supply nutrients to eye
Retina
innermost layer of eye
Contains photoreceptors
Cornea
First part of the eye that light passes through
Gathers and focuses incoming light
Iris
Colored part of eye
composed of dilator and constrictor pupillae
Cilliary Body
Produces the aqueous humor that bathes the eye
Lens
right behind iris
Helps control refraction of incoming light
Vitreous humor
Behind the lens
transparent gel that supports the retina
Retina
back of eye
Consist of neural elements and blood vessels
Convert incoming light photons into electrical signals
Rods
Highly sensitive to photons
Contain pigment type rhodopsin
Only allow sensation of light and dark
Macula
High concentration of cones
Central part of retina
Fovea
Contains only cones
