Chapter 3: Perception Flashcards
Perception
processes that interprets information from
our senses to allow us to produce an internal
representation of the world sufficient for us to recognize and interact with our environment
Transduction
the transformation of physical stimuli (sights, sounds, smells) into neural impulses
Sensation
Encoding stimulus energy into neural impulses
Inverse Projection Problem
challenge the brain faces when trying to figure out what an object is just from the image that hits our eyes; processing 2D image on the retina as a 3D (shadowy/figure in distance)
viewpoint invariance
the ability to recognize an object from different angles, even when it looks different from each viewpoint (chair rotating)
Bottom-up processing
Perception based on incoming signal from the senses
- Energy registering on receptors
Top-down processing
Perception based on information already stored in the
brain
- Person’s knowledge, experience, expectations
Direct perception theories
Perception comes from stimuli in the environment
- Parts are identified and put together, and then recognition occurs
Constructive perception theories
People actively construct perceptions using information based on expectations
Speech segmentation
the process of distinguishing words in the continuous flow of speech sounds (statistical/transitional learning)
Helmholtz’s Theory
Some of our perceptions are “unconscious inferences,” where the brain actively interprets sensory information based on past experiences and knowledge to create a coherent perception of the world
Likelihood principle
we perceive the world in the way that is “most likely” based on our past experiences (assuming a blurry image is a cat because you know cats look like that in the past)
Gestalt’s laws of perceptual organization
our brain naturally organizes visual information into meaningful patterns; Instead of seeing random shapes, we group things together based on certain principles
Law of good continuation
Lines tend to be seen as following the smoothest path
Law of Good Figure (pragnanz)
Every stimulus pattern is seen so the resulting structure is as simple as possible
Law of similarity
Similar things appear grouped together
Law of familiarity
Things are more likely to form groups if the groups
appear familiar or meaningful
Law of proximity
Things near each other appear grouped together
Law of common fate
Things moving in the same direction appear to be
grouped together
Heuristic
Provides best-guess solution to a problem and answers that have usually been correct in the
past (fast, often correct)
Algorithm
Procedure guaranteed to solve a problem; assuming all the necessary information is available (Slow, definite result)
Oblique effect
People can perceive verticals and horizontals more easily than other line orientations
Light-from-above heuristic
light usually comes from above, because in the real world, the sun and most light sources (like ceiling lights) are above us. Our brain uses this assumption to interpret shadows and depth in images
Palmer (1975)
conducted experiment to see how prior knowledge can influence perception. context plays a role in perception (bread/kitchen)
Bayesian Inference
model of how the brain makes decisions and inferences by continuously updating its beliefs about the world based on new sensory information, using a statistical method (Prior probability and Likelihood)
Experience-Dependent Plasticity
Experiments have shown that neurons become more
strongly tuned to aspects of the environment that occur frequently; experience shapes how we perceive the world over time
Brain Ablation
a research method that involves damaging or removing brain tissue to study how it affects behaviour (usually monkeys or cats)
Single dissociation
one brain function is damaged but the other is not; shows that two function are independent but still connected; A patient can understand language but cannot speak - damage to broca but not wernicke’s
Double dissociation
two different brain functions are damaged in separate cases; one is impaired in one patient, while the other is impaired in another - damage to the same area but causes different impairment
Object discrimination
Helps us recognize and identify objects (color, shape, size); Located in the temporal lobe (what); damage causes inability to recognize a familiar object like a coffee cup, even though they can still reach for it
Landmark discrimination
Helps us determine an object’s location and movement; Located in the parietal lobe (where); damage causes ability to recognize a coffee cup but struggle to reach for it accurately
