Perception (CH 3) Flashcards
What is Perception?
- Experience resulting from stimulation of senses
- Ability to see, hear, become aware of something through senses
What are the 6 Basic Characteristics of Perception?
- Can change based on added info
- Involve process similar to reasoning & problem solving
- Perceptual rule= when objects overlap, the one underneath usually continues behind the one on top
- Arriving at a perception= involve complex processes that include reasoning
- Occurs in conjunction w/ action= central to our ability to organize the actions that occur when we interact w/ environment
- Creates a picture of enviorment= essential for creating memories, acquiring knowledge, solving problems, communicating/ recognizing others
What was making Computers-Vision system that perceives objects & scenes all about?
- Estimated in the 1950s that it would take a decade to design a machine that would rival human vision
- International Journal of Computer-Vision (1987)= contained many papers where they resorted to complex math formulas to solve perceptual problems that are easy to humans
- Defense Advanced Project Agency (DARPA)= Tasked to produce a self-driving car to drive 150 miles= really difficult bc computer still made mistakes naming objects & don’t have a huge storehouse of info about the world like humans
Why is it so hard to create a Perceiving Robot?
- Stimulus on receptors are ambiguous bc it starts on the Retina and its job is to determine what object “out there” created that image
- Inverse Projection Problems that bots can’t solve
- Objects can be hidden or blurred= humans can easily determine what an object is based on its environment
- Objects look different at different viewpoints= Viewpoint Variance that humans possess
- Scenes contain high-level info
What is Bottom-Up Processing?
-Starts at “bottom” of the beginning of a system when environmental energy stimulates receptors
What is Top-Down Processing?
- Originates in the brain at “top” of the perceptual system
- Helps people rapidly identify objects, scenes, and determining story behind scenes
What is Speech Segmentation and how does it work?
- The ability to tell when one word in a convo ends & the next begins
- The continuous sound signal enters the ears and triggers signals that are sent to speech areas of the brain (BOTTOM-UP PROCESSING)
- If the listener understands the language their knowledge creates a perception of individual words (TOP-DOWN PROCESSING)
What are Transitional Properties?
- As we learn a language we start to recognize the likelihood that one sound will follow another within a word
- The process of learning these properties= Statistical Learning
What was Helmholtz’s Theory of Unconcious Interface?
- Based on realizations that image on the retina is ambiguous
- The particular pattern of the retina is caused by # of objects in the environment
- Likelihood Principle= Perceiving objects that is most likely to have caused the pattern of stimuli we received
- Unconcious interference= judgment of what most likely occurs/ assumptions that we make about the enviornment
- Optical illusions= we can’t unsee what we see even if we know how it works
What is the Gestalt Principle of Organization?
- Originated as a reaction to Wundt’s structuralist ideas= Gestalts perception could not be explained by adding up small sensations
- There’s 3= Good Continuation, Pragnanz, Similarity
- Apparent movement= moving displays/ headlines
- The whole is different from the sum of its parts= propose principles of perception organization
- EXPERIENCE plays MINOR role in perception
What is the Good Continuation Principle of Organization?
- When points are connected= straight & smooth= as seen as belonging together
- Objects that are overlapped= percieved as continuity behind overlapping object
What is the Pregnanz Principle of Organization?
- Good figure/ simplicity
- Every stimulus pattern is seen in such a way that the resulting structure is as simple as possible
What is the Similarity Principle of Organization?
-Similar things appeared to be grouped together (size, shape, color, orientation)
What are Physical Regularities?
- Regularly occuring physical properties of the enviornment (vertical & horizontal orientations)
- We perceive horizontal & vertical orientations better than angles= Oblique Effect
- When object partially covers another one, the contour of the partially covered object “comes out the otherside”
- Light from Above Assumption= Our perception of illuminated shapes is influenced by how they’re shaded combined w/ assumption of light from above
- Our system is adapted to respond to physical characteristics of enviornment like orientations and direction of light
What are Semantic Regularities?
- Characteristics of a scene are associated w/ functions carried out in different types of scenes= meaning of a scene
- Scene Schemas= expectations that contribute to our ability to perceive objects &; scenes
What is the Bayesian Inference?
- Method of statistical inference where Bayes theorem is used to update the probability of a hypothesis as we receive more info
- EX; while retinal image is a starting point for percieving the shape of the book, adding the person’s prior beliefs reduces the possible shapes that could be causing image
- Prior x Likelihood= probability of outcome
- Restates Helmholtz idea that what we perceive most likely have created the stimulation we have received in terms of probabilities
Why do Neurons respond better to Horizontal and Vertical orientations vs Obliques?
- Theory of Natural Selection= visual systems that respond best to often & naturally occuring orientations are passed down= increased survival
- Learning can reshape the response properties of neurons through Experience- Dependant plasticity
What is Experience- Dependant Plasticity?
- Shaping of neural response by experience
- Plays role in determining these neurons response to faces by measuring level of activity in FFA w/ response to faces & objects (greebles)
- Neurons can adapt to operate best within a specific environment
How does Movement Facilitate Perception?
- Helps us perceive objects in the environment more accurately
- Reveals aspects of objects that are not apparent from a single viewpoint
- Different viewpoints= added info= more accurate perception
- Coordination that is continually occuring between perceiving stimuli & taking action toward these stimuli
What is Brain Ablation?
-Study of the effect of removing parts of brain in animals
What is the ‘What’ Pathway?
- AKA Ventral Pathway
- Pathway from Strirate Cortex to Temporal lobe that is responsible for determining object identity
What is the ‘Where’ Pathway?
- AKA Dorsal Pathway
- Pathway from Strirate Cortex to the Parietal Lobe that is responsible for determining object location
What Corresponds to the ‘What’ Pathway?
- Perception Pathway
- Pathway from Visual Cortex to Temporal Lobe
What Corresponds to the ‘How’ Pathway?
- AKA ‘Action’ Pathway
- Pathway from Visual Cortex to Parietal Lobe
- Also corresponds to ‘Where’ pathway
What Pathway does “Identifying coffee cup” use?
-Perception/what
What Pathway does “Reaching for cup” use?
-Action/where
What Pathway does “Grasping cup” use?
-Action
What pathway does “Perceiving handle” use?
-Perception
What pathway does “Lift cup w/ right amount of force” use?
-Action
What pathway does “Estimation of fullness of cup” use?
-Perception
What are Mirror Neurons?
- Distributed throughout brain= Mirror Neuron System
- Code the “why” of actions & respond differently to different intentions
- The response is determined by the sequence of motor activities that could be expected/ most likely to happen in a particular context
What part of the brain is associated with the Landmark Discrimination task?
- Parietal lobe
- Occurs when Parietal lobe is removed
- Utilizes “Where” pathway
What part of the brain is associated with Object Discrimination task?
- Temporal lobe
- Utilizes “What” pathway
How are Top-Down Processes used in Human Perception?
- Knowledge that enables people to rapidly identify objects & scenes
- Determining story behind a scene
How are Bottom-Up Processes used in Human Perception?
- Image on retina creates electrical signals that are transmitted through the retina then to receiving area of the brain
- Starts at “bottom”/ beginning of the system when environmental energy stimulates receptors
