Cognitive Unit 3
Explain what it means to interpret scenes based on cues present in those scenes
This describes the computational approach to the study of perception. Cues in the stimuli such as basic features, linear perspective, and retinal size help us interpret the size and distance of objects in the environment and also help us identify those objects.
Sensory system?
system that receives and processes input from stimuli in the environment
what is perception/action approach?
- consider perception as means to achieve behavioral action goals ("what for" aspect of the perception) - considering movement in terms of goals for our own action
Things that affect our perceptual set?
- culture - context (e.g. if the duck/bunny was surrounded by easter eggs, it may be easier to see it as easter eggs) - emotions (e.g. people will say hill is more steep if they're listening to sad music) - motivation
Four parts of a sensory system? examples of each?
1) Sense Organ (eyes, nose, tongue, etc) 2) Receptor cells (rods, cones in the retina) 3) Nerve Conduit to the brain (optic nerve) 4) Brain area where the information is being processed (occipital lobe of the brain) - with tensions to other areas to connect with other cognitive processes
The _____________ visual pathway extends into motor cortex, whereas the ____________ visual pathway extends into the temporal lobe where language is processed. The inform
1) ventral 2) dorsal
In what way do illusions illustrate the normal process of perception?
Because we use cues to interpret stimuli, those cues can sometimes lead to an inaccurate interpretation when they conflict with or are not an accurate representation of the environment.
What is computational approach?
Describes perception to some degree as relying on representations of the world, with a proximal stimulus created in our minds to represent the distal stimulus in the environment?????
Example of figure ground relationship
E.g. the voice of your crush is figure Everything other sound that's blocking is ground
Would the gestalt approach to perception explain the moon illusion?
No, because moon illusion uses a horizontal line illusion and it involves more than just gathering the parts of the scene
would a perception/actinon researcher be interested in explaining the moon illusion?
No, because you're not doing anything in a action by going to the moon.
Proximal stimulus Vs Distal Stimulus
Proximal=what you actually perceive . Distal=What is causing the stimulus Distal stimulus is the actual object, such as a picture, or tree, person, etc Proximal stimulus is what the distal stimulus is giving that you can sense--light stimuli, auditory stimuli, etc. it's the component that must be sensed by your sensory receptors.
perceptual set
The psychological factors that determine how you perceive your environment (believing is seeing)
How do you know the pot is closer to the cat?
The retinal image size of the pot is larger than the retinal image of cat. The cat is also higher in the photo: thus linear perspective may help us determine that it is farther away.
Role of receptor cells in perception?
There receptor cells convert stimulus energy (e.g. light, sound waves) to neural signals that can be received and processed by the brain
Ventral Stream Vs. Dorsal
Ventral Stream: WHAT pathway Dorsal Stream: WHERE pathway
Rule of proximity?
We like to group nearby figures together (e.g. grouping band geeks, football jocks, etc at a party) `
Why does the moon illusion occur?
When moon is closer to the horizon, it is surrounded by objects that are much smaller than the moon. because it is so close to these smaller objects, such as trees and buildings, it appears huge in comparison. When the moons high in the sky, it is only surrounded by the vastness of the sky so it appears much smaller in comparison
What is Gestalt psychology?
When trying to make sense of the world around us, Gestalt psychology suggests that we do not simply focus on every small component. Instead, our minds tend to perceive objects as part of a greater whole and as elements of more complex systems.
Perception
the top-down way our brains organize and interpret that information and put in to context
retinal disparity
a binocular cue for perceiving depth
How is top-down processing involved in the Gestalt approach to perception?
bc gestalt approach says it's "more than the sum of its parts" - relies more on top down processing and our knowledge of the world in the form of organizing principles to help us perceive the world
I see flowers outside, I imagine going out to smell the lowers. How is this perception/action approach?
bc you're thinking about going out TO smell the flowers (what for approach - going for the smell of lilac)
monocular cues
depth cues, such as interposition and linear perspective, available to either eye alone
binocular cues
depth cues, such as retinal disparity, that depend on the use of two eyes
What is an affordance?
possible behaviors in a given environment
depth perception
the ability to see objects in three dimensions although the images that strike the retina are two-dimensional; allows us to judge distance (e.g. you can look at a picture of your crush on instagram as two dimensional, but you can imagine their actual figure as 3d)
Figure ground relationship
the organization of the visual field into objects (the figures) that stand out from their surroundings (the ground). ( e.g. faces or vases?)
constancy
the tendency to perceive certain objects in the same way regardless of changing angle, distance, or lighting (e.g. I can recognize my crush even if someone blocks half of my view)
Bottom up processing?
understanding the environment through basic feature identification and processing
Top Down Processing
understanding the environment through global knowledge of the environment and its principles
What are the advantages to having a perceptual system that has automatic input of all environmental stimuli but only consciously processes a small portion of those stimuli?
we can focus our attention on (or attention can be captured by) any stimuli in the environment because all are being received. Thus, we have the ability to consciously process any stimulus in our environment.
Theory of unconscious inference
we make unconscious inferences about the world when we perceive it. In other words, we use our top-down processing unconsciously to perceive and interpret the environment.
rule of continuity?
we perceive smooth, continuous patterns rather than discontinuousness
likelihood principle
we perceive the object that is most likely to have caused the pattern of stimuli we have received (e.g. we would think a bright flash of light in the darkness is from a car coming, NOT a UFO)
rule of closure
we tend to fill in missing elements of a visual scene
Principle of pragnantz
we view scenes in the most concise way possible, with a simple interpretation
Your brain ___ your ____
your brain constructs your perception