L2 - Perception Flashcards
Define Sensation
Detection of simple properties of stimuli
Define Perception
Detection of objects and their location
How we interpret something
What are the two types of codes?
Anatomical: position of neurone
Temporal: no of action potentials in a specific place
What are Monocular & Binocular cues?
M: If one object is placed in front of another, obscuring it, we can tell which one is closer, Also called interposition
B: Visual fields of both eyes overlap
What is Linear Perspective?
Parallel lines that recede appear to converge at a point
What is Texture a cue for?
Coarser = closer
Finer = distant
What is Shading a cue for?
3D shapes
What is Elevation a cue for?
Closer to horizon = further
What is Haze a cue for?
Hazier = further
What is the Size-weight illusion?
Two objects of equal weight, the smaller will be perceived as heavier
What is Brightness constancy?
People judging the whiteness/greyness of an object very well even if illumination changes.
What is Form Constancy?
Unchanging perception of an objects size/shape when it moves relative to us
What does Ames Window try to do?
Show Shape Constancy
What is the moon illusion? What does it show?
- The moon looks bigger at the horizon than it does elsewhere.
- Depth illusion
- Shows perceptual constancy
- Perceived size depends on perceived distance and size of nearby objects
- Small stimuli far away are large objects
- Large stimuli close by are small objects
What are illusions?
Interpreting of confusing sensory signals
How are basic features perceived?
Through context of shapes and your experience
Describe Lotto’s cubes
Colour depends on perceived lighting, shape and shadows
How do you perceive white?
Same wavelength in all cones
How do you perceive blue?
Short cone has more activity than others
How do you perceive yellow?
Short cone has least activity than others
How do you perceive green?
Medium cone has most activity
How do you perceive red?
Longest cone has most activity
What do Van Lier stars show?
- After image
- Filling in shape when you look at dot, not when you look at shape
- Only see one after effect at a time, black lines must move them
Why do the colours change?
- The perceived colour has a cone that is most active
- This activity drops after looking at the colour for a while
- When switching to white, it takes time for it to reconfigure so looks like a different colour