Chapter 5 - Percieving Objects Flashcards
What Factors play a role in perception?
- Physiological
- Devleopmental
- Role of Experience
- Society, Culture, and Enviornment
- Langauge
What are the difficulties with designing a perceviging machine?
- Stimulus ambiguity
- Viewpoint invariance
- Occulsion
What is stimluus ambiguity?
- Inverse projection problems
- An image on the retina can be caused by an infinite number of objects
What is viewpoint variance?
- The ability to recognize an object regardless of the viewpoint
- Difficult for a computer to do
What is occulsion?
- Objects can be hidden or blurred
What are specific principles of perceptual orginization?
- Apparent movement
- Illusory contours
- Grouping
- Segregation
- Good continuation
- Pragnanz
- Similarity
- Proximity
- Common fate
- Common region
- Uniform connectedness
What is good continuation
Connected points resulting in straight or smooth curves belong together
What is pragnanz?
Every stimulus is seen simply as possible ( olympic rings )
What is similarity?
Similar things are grouped together ( color, shape, size, etc )
What is proximity?
Things that are near to each other are grouped together
What is collon fate?
Things moving in the same direction are grouped together
What is common region?
Elements in the same region tend to be grouped together
What is uniform connectedness?
Connected region of visual properties are perceives as single unit
What is the perceptual difference between an object and a scene?
- An object is compact and acted upon
- A scene is expansive in scope and scenes are acted within
What is physical regularities?
regularly occurring physical properties
What is oblique effect?
people perceive horizontals and verticals more easily than other orientations
What is uniform connectedness?
objects are defined by areas of the same color or texture
What is light from above heuristic?
light in the natural environment comes from above us
Frontal Cortex ( FC )
Activated when evaluating facial attractiveness
Superior Temporal Sulcus ( STS )
Responds to where the person is looking and to mouth movements
Amygdala ( AG )
Activated by emotional aspects of faces
Fusiform Face Area ( FFA )
responds only to faces
Crouzer et al showed what about faces?
- Eye movements in responses to faces at 138 ms, animals at 170 ms, and vehicles were at 188 ms
- Faces have special status and are processed more efficiently and rapidly than other classes of objects.
Meng et al. showed what about faces?
- FFA on left side and right hemisphere have different functions. Non-face stimuli that resembled faces, orders with most face-like stimuli on the right.
- Responses of left FFA; response increases as stimuli become smore face like
- Responses to right FFA; Responses are low for any non face stumli but jump when presented with a real face.
- Right only responds to real faces
Palmer experiment on context showed what?
Observers saw a context scene flashed briefly, followed by a target picture. Results showed that targets congruent with the context were identified 80% of the time.
Potter’s research showed what?
- Showed that people can do this when a picture is presented for ¼ second
- Target photo or written description followed by 16 rapidly presented pictures, observer responded if the target picture had been presented, almost 100% accuracy rate for target picture, 90% for written text
