Week 3: Perception Flashcards
What is perception?
experience resulting from the stimulation of the senses
What 2 types of information are involved in perception?
- environment stimulation of receptors
- knowledge and expectations of observer
Direct theories of perception
- bottom-up processing
- comes from environmental stimuli
- parts identified and then put together
Constructive theories of perception
- top-down processing
- actively construct perceptions using info based on expectations
Is the Gestalt principles top-down or bottom-up processing?
bottom-up
What is bottom-up processing?
- perception may start with the senses
- incoming raw data
- energy registering on receptors
What is top-down processing?
- perception may start with the brain
- persons knowledge, experience, expectations
- some are result of assumptions we make about the environment
- likelihood principle
What is the likelihood principle?
perceive world in way that is “most likely” based on past experience
“new” view of perceptual organization
gestalt principles
Gestalt principles
- principle of good continuation
- law of pragnanz
- principle of similarity
- principle of proximity
- law of closure
Principle of good continuation
lines tend to be seen following the smoothest path
Law of Pragnanz
every stimulus pattern is seen so resulting structure is as simple as possible
Principle of similarity
similar things appear grouped together
principle of proximity
objects near each other tend to be grouped together
law of closure
- objects grouped together are seen as a whole
- gaps are “filled in” to create similar shapes and images
What are the environmental regularities?
- oblique effect
- scene schema
- light from above
Oblique effect
perceive verticles and horizontals more easy than other orientations
Scene schema
knowledge of what a given scene ordinarily contains
Light from above
we assume light comes from above because its common in our environment
Experience-dependant plasticity
- some neurons respond best to things that occur regularly in environment
- neurons become tuned to respond best to what we commonly experience (horizontals and verticles)
“What” pathway
- ventral
- determine identity
“Where” pathway
- dorsal
- determine location
What are mirror neurons
neurons that respond while watching an action performed as if the subject was performing the action themselves