Lesson 4: Perception Flashcards
Perception
Experiences resulting from stimulation of the senses
Perceptual Process
Environmental stimulus, stimulus on receptors, transduction, processing, perception, recognition, action (repeat)
Sensation Vs. Perception
- Perception changes based on what you consciously perceive
- Sensation remains the same while perceiving different things
The Dress
Color differs based on past experiences and bias
- White + Gold = Natural lighting (Morning owl)
- Black + Blue: internal lighting as you subtract red light from image (Night owls)
Top Down Processing
- Previous experience/knowledge plays a role in how you recognize and perceive things
- Multiple personalities of a Blob (same retinal image, different perception)
Recognizing things when they’re different
Don’t solely use basic features to perceive things: Recognize things when they’re ambiguous, blurred, or distorted, or from various viewpoints (Viewpoint invariance)
Inverse Projection Problem
An image on the retina can be caused by an infinite number of objects
Speech Segmentation (Top-down)
- Statistical learning about characteristics of languages begins at 8 months old
- Kids were given segment fake words and only recognized the novel words within the segment of fake words
Pain Management (Top-down)
- Nocebo effect: Pain goes up after told pain medications stopped even though they didn’t
Endorphins: Endogenous opioids inhibit neurons sending pain signal = tells brain no pain (distraction, sex, laughing, exercise)
- Helmholtz’s Unconscious Inference
Likelihood Principle: Assumptions happening rapidly and quickly based on our previous experiences
- Considering Environmental Regularities
Physical: More vertical/horizontal lines in environment, object ocluded comes out other side, light from above assumption
Semantic: Meaning of a scene, schema (knowledge of what belongs in a scene) (multiple personalities of a blob)
- Bayesian Inference
One’s estimate of probability of an outcome influence by:
1. Prior probability (initial belief)
2. Likelihood of an outcome (based on current evidence)
- gestalt Principles of Organization
- Innate
- Law of Good Continuation: Continue contours when elements of pattern established an implied direction
- Law of Simplicity: Forms with he most simplicity, regularity, and ease of remembrance most easily understood. Logic. Group objects with similar properties.
- Law of Proximity: Close objects are not seen as separate but part of a whole
- Law of Common Fate: Group objects that move in the same direction
- Principle of Common Region: Elements within the same region of space are grouped together
FFA
Can respond to faces and things we are visual expertise’s at like a Jeweler with jewelry
Penfield’s Neurosurgery
Study of living reacting brains. Temporal lobe epilepsy.
Cortical plasticity
Bigger space on homunculus for thigns that we use often.
- Brain forms new neural connections based on what we experience more and less
- Like left hands for stringed instrument player would be bigger on map than noninstrument players.
- Phantom limb sensation because spot on brian gets taken over by whatever is next to it, so you get touched on genital and think you feel your feet
What (Ventral/Temporal) and Where (Dorsal/Parietal) Pathways
Process information in our environment
Monkey task
Object Discrimination (what): Could not determine what shapes were but knew where they were
Landmark Discrimination (where): Could not determine where shapes were but knew what they were
Patient DF
Agnosia (Anoxia - No O2 b/c CO poisoning)
- Could not identify objects or people unless it was put in her hand or they spoke
- Cannot describe orientation (Cannot do where but can do what)
- Cannot draw objects but can interact with them if she’s holding or on them
- temporal damage
Visual Agnosia (Where pathway)
See items but cannot identify what they are unless you hold them
Double Dissociation
Visual agnosia versus optic ataxia
Patient RV
-Bilateral parietal damage
- Could not grasp objects but could copy objects
