Motion Perception Flashcards
What is information provided by motion?
Attracts our attention
Provides information about the object’s 3D shape
Provides information that helps us segregate the figure from the ground
Provides information that enables us to interact with the environment
What types of cells are responsible for handling motion?
Magno cells
How did Ramachandran discover that magno cells handle motion?
Used isoluminant stimuli
There are no lightness differences
Stimuli were moved against the background but it is difficult to perceive motion
What are the problems with the Reichardt motion-detector circuit?
Following a moving object with you eyes: object is perceived as moving even though retinal position does not change
Sweeping you eyes across a stationary scene: it appears to be motionless
What is some motion perception with CDS?
Observing afterimage in a dark room
Pushing on eyeball but keeping eyes stationary
Pursuit: moving object, eyes move with it
Eyes paralyzed, try to move your eyes
What is apparent motion?
When it looks like their is motion depending on the timing but really it is simply just frames
60 ms for continuous movement between frames
What does percept depend on for apparent motion?
Distance between stimuli
Frame duration
Stimulus onset asynchrony
What is the SOA law?
Changes in interstimulus interval and frame duration do not affect motion perception unless there is also a change in SOA
What is the nearest-neighbor principle?
Select alternative the minimizes overall travelling distance of elements
What is the wagon wheel illusion?
Occurs when a rotating spoked wheel is perceived as moving backwards in films
Due to a discrepancy between the speed of rotation and the rate of filming
What is the uncanny valley?
The more robots appear humanlike, their shinwakan increases until a valley is reached in which subtle perfections create a strangeness
Motion produces a larger valley
What are the pros of the uncanny valley?
May provide framework for making robots more humanlike
May contribute to an understanding of social interaction
What are the cons of the uncanny valley?
Shinwakan may be a confounding of strange/familiar and eerie/not eerie
Criticized as a pseudoscience
Evidence equivocal
What is a kinetoscope?
First motorized film projector
What are motion requires for film?
On-screen image must be filter free
Slightly different frames must be shown in succession
