Psychological, Social, Biological Foundations of Behavior Flashcards
Retinal Disparity
Left eye and right eye view slightly different images. One type of binocular cue.
Convergence
Gives an idea of depth based on how much the eyeballs are turned. The second type of binocular cue.
Monocular cues
Relative size, interposition, relative height, motion parallex (relative motion),
Relative size
See relative size and determine approximate distance.
Perceptual Organization
Depth, Form, Motion, Constancy
Interposition
When something appears to be in front of something else, we can recognize that it is closer to us.
Relative height
Objects that are higher are perceived to be further away than objects that are lower.
Motion parallex (Relative motion)
Things closer to you appear to be moving faster than things that are further from you.
Size constancy
We know size of objects are roughly the same regardless of distance from eyes.
Shape constancy
We know the shape of an object remains the same even if it is reoriented.
Color constancy
Despite changes in lighting, color for an object is perceived as the same color.
Sensory adaptation
Change in sensitivity of your perception of a sensation.
Hearing: inner ear muscle contracts to dampen vibrations that go into your inner ear.
Touch: sensory receptors get saturated.
Smell: sensory receptors desensitized.
Sight: pupil dilation and contraction.
Proprioception
Sense of where you are in space.
Just noticeable difference
The smallest difference in stimulation that can be detected 50% of the time.
Weber’s law
Change in a stimulus that will be just noticeable is a constant ratio of the original stimulus.
Absolute threshold of sensation
Minimum intensity of a stimulus that is needed to detect a particular stimulus 50% of the time.
Subliminal stimuli
Stimuli below our absolute threshold of sensation
Thermoception
sensation of temperature; TrpV1 receptor used– heat causes conformational change
mechanoception
sensation of pressure
nociception
sensation of pain; TrpV1 receptor used– broken cell molecules bind to receptors to cause conformational change
somatosensation
intensity, timing, location
intensity
how quickly neurons fire
3 ways for neurons to encode timing
non-adapting (neuron constantly firing action potentials, equal space between action potentials), slow adapting (fires fast at the beginning, and then slows down, spacing increases), fast adapting (fires as soon as stimulus starts, then it stops, and starts again when the stimulus stops)
vestibular system
important for sense of balance and spatial orientation, mostly comes from receptors in our inner ear
Inner ear’s role in vestibular system
Semi-circular canals line up with the 3 axes and sense what plane our head is rotating along. Fluid movement helps us perceive the strength of rotation. Otolithic organs (utricle and saccule) help detect linear acceleration and head positioning, crystals in fluid move and pull on hairs to carry this information. Dizziness results from fluid in canals moving while you are no longer moving.
Signal Detection Theory
How we make decisions under conditions of uncertainty; discerning between important stimuli and “noise”
Hit
affirmative response with signal present
false alarm
signal perceived but no signal present
correct rejection
negative answer and no signal present
miss
negative response with signal present
d’
difference between the means of 2 signal distributions – if large, easy to distinguish, if small, difficult to distinguish
c
strategy of the individual, can be expressed via choice of threshold; c=0 ideal observer, c<1 = liberal, c>1 conservative strategy
bottom-up processing
when you start with no preconceived idea of what it is that you’re looking at, and allow the stimulus to influence your perception of what it is that you’re looking at; data driven
top-down processing
use background knowledge to influence perception; theory driven ; have a goal in mind
Gestalt principles
seek to explain how we perceive things the way we do
law of similarity
items that are similar to one another are grouped together by your brain
law of pragnanz
reality is often reduced or organized to the simplest form possible
law of proximity
objects close to one another are grouped together
law of continuity
lines are seen as following the smoothest path
law of closure
objects grouped together are seen as a whole
sclera
white part of the eye, thick fibrous tissue that forms the substance of the eyeball, protects the eye, and serves as attachment point for muscles
cornea
transparent, protects front of the eye, bends light a little bit
conjunctiva
thin layer of epithelial cells that protect the cornea from friction/dust/debris and moisturizes it