Chapter 8 - Lecture Section 8.1 Flashcards
Why is Motion perception is important for survival?
Helps detect prey (e.g. frog hiding) and predators (e.g. leopard stalking)
What information does Motion provide about an object?
- Object shape and segregation
- Attention, is highly salient
- Depth
- Navigation + Proprioception/balance
Motion can be useful for ___ an object from its surroundings.
segregating
Motion separates ___ from ___.
figure // ground
Motion is a highly-salient, attention-grabbing feature, it’s a very good way of inducing ___.
Attentional Capture
What is a break in camouflage?
A break in camouflage is when an animal or person is camouflaged, but when they start moving, you’re able to discern their structure from the surrounding structure.
A break in camouflage is an example of ___.
Attentional Capture
How does Motion help with object recognition?
Motion helps with object recognition (depth/shape/form from motion) either when you are able to move, or the object is moving relative to you and you see all of the different parts of the object, and so you can discern shapes that were only visible from certain viewpoints.
Motion can add a sense of ___ to a ___ image.
shape // flat
What is the Kinetic Depth Affect?
The gif of a field of dots that are moving in a particular way, and because of the speed of motion of each dot is set up in a specific pattern what you typically see is a rotating sphere.
The impression that this is a rotating sphere is called the Kinetic Depth Affect
What is the most powerful depth cue?
Motion Parallax
Motion Parallax requires ___.
Motion
Motion Parallax helps with ___.
Depth perception
Visual motion is also important for the processing of ___, the movement of your body through the environment.
Self-motion (Optic flow)
What Self-Movement skills are needed when driving/flying?
- Navigation
- Steering
- Speed estimation
What Self-Movement skills are needed for body sense??
- Navigation
- Trajectory
- Speed
- Posture
- Balance
What have studies shown about your trajectory through the air?
Studies have shown that your trajectory through the air is more repeatable and accurate if you have your eyes open, so that includes visual signals.
What is Motion Agnosia (Akinetopsia)?
Damage to various modules along the dorsal/Parietal stream can impair the perception of motion, causing the inability to see motion.
Patient L.M. had a stroke to area ~Middle Temporal (MT) cortex, and can no longer perceive ___. Despite the fact that it’s in the Temporal Cortex, we will see that this is actually in the Dorsal Stream
motion
Patients with Motion Agnosia (Akinetopsia) are able to perceive ___, and see the consequences of things that have moved, but are unable to perceive the ___ itself.
form // motion
True or False: Photoreceptors can code motion
False. Photoreceptors can code light intensity, but photoreceptors cannot code motion, therefore any motion signal that enters into our visual system must be calculated from the inputs of multiple neuron.
True or False: Perceiving motion is as simple as having an image move across the Retina, and then we perceive motion.
False: Visual motion is that perceiving motion is not as simple as having an image move across the retina and then we perceive motion.
What are the 5 other problems of visual motion?
- Apparent motion
- Induced Movement
- Motion Aftereffects
- Tracking a moving object
- Self-motion
What is Apparent Motion?
How when a still object changes position with just the right timing, we perceive it is moving from one position to another. This was discussed when we talked about Gestalt Psychology,
Anytime you are watching a video on a screen, this is always ___, it is the successive presentation of a bunch of still images, one after the other.
Apparent Motion