-
auditory perception
determine words, identify speaker, localize sound in space
-
visual perception
- differentiate objects
- determine position motion shape, texture
- make contact with long term memory
-
templatic hypothesis
- we store images of encountered objects
- we can recognize objects based on their familiarity
- (INCORRECT)
-
problems with templatic hypothesis
- we can recognize things we've never seen before
- we can recognize objects from new angles
- we can recognize objects when features are missing
-
segmentation
- achieved by:
- edge detection
- determining figure group
- grouping
-
what is the sensory input and perceptual output of vision?
- sensory input: 2-D array of color and luminance values
- perceptual output: 3-D objects
-
what is sensory input and perceptual output of audition?
- sensory input: sequence of air pressure values
- perceptual output: words
-
How do we identify edges?
enhance contrast (ex. mach bands)
-
lateral inhibition
adjacent neurons inhibit each other to enhance contrast
-
how does the herman grid exhibit lateral inhibition?
black squares make the white pathways more white, so corners appear darker
-
how do we find lines in segmentation?
- each neuron responds to a point in the visual field
- When a bank of on-center, off-surround cells are jointly firing, this indicates a line
-
figure ground
determining what is object and what is environment
-
gestalt principles
- heuristics for organizing visual objects
- similarity
- proximity
- good continuation
- closure
- simplicity
-
binocular disparity
distance between the eyes causes the visual scene to appear slightly differently on the two retinas
-
texture density gradient
- less density in same images = indicates closer proximity
- more density =distance
-
how does light effect our visual perception?
location and effects of light source give us depth cues
-
occulsion
we can tell about an object's relative position based on the objects in front of and behind that object
-
4 cues to object location
- binocular disparity
- light source-depth cues
- occlusion
- texture density gradient
-
normalization
disregarding irrelevant surface materials in order to make contact w. long term memory
-
color constancy
- be able to understand that colors remain the same even in different lightings
- example of normalization
-
top down processing in visual perception
we formulate a hypothesis about the identity of a stimulus, select and examine relevant aspects of the stimulus to check
-
convergence
brain uses how much eyes turn to view nearby objects to determine depth perception
-
ames boxes
rooms which play with linear perspective and distance clues
-
ponzo illusion
when two lines begin to form a triangle and there are two lines in between those other lines, the two lines inbetween appear to be different in size
-
motion after effects
if you stare at a moving image and then look at a stationary scene, the stationary scene appears to move
-
bottom up processing
info from sensory receptors is combined to make more complex and recognizable patterns
-
monocular vision cues (6)
- occlusion
- relative size
- familiar size
- linear perspective
- texture gradient
- position relevant to horizon
-
binocular vison cues (2)
- retinal disparity
- convergence
-
motion parallax
the relative movements of objects at various distances from the observer
-
iris
changes shape to let in more/less light
-
pupil
small opening in eye which lets in light waves
-
What are the four possible outcomes in signal detection theory?
- hit
- miss
- false alarm
- correct rejection
-
sensory coding
the process by which sensory organs translate the physical properties of stimuli into neural impulses
-
What are on-center, off-surround cells and how do they contribute to finding lines?
- on-center off-surround cells selectively fire when light is in the center of their receptive cells.
- When a bank of on-center off-surround cells are firing together, this is indicates a line
|
|
