Sunday, April 20, 2014

Sensation and Perception

- Sensation: your window to the world
- Perception: interpreting what comes in your window
  • Sensation- process by which our sensory receptor and nervous system receive stimulus from the environment
    • Bottom-Up Processing: begins with sense receptors and works up to brain's integration of sensory information
    • Top-Down Processing: information processing guided by higher level mental processes
    • Absolute Threshold: minimum stimulation needed to detect stimulus 50% of time
    • Difference Threshold: minimum difference that the person can detect between 2 stimuli
    • Just Noticeable Difference (JND): smallest detectable difference between a starting and secondary level of a particular sensory stimulus
    • Weber's Law: idea that to perceive difference between 2 stimuli, they must differ by constant percentages; not a constant amount
    • Signal Detection Theory: predicts how we detect a stimulus amid other stimuli
    • Sensory Adaptation: decreased responsive to stimuli due to constant stimulation
      • Example: don't need to feel if underwear is there or not
    • Selective Attention: focusing of conscious awareness on a particular stimulus
    • Cocktail-party Phenomenon: ability to focus one's listening attention on a single talker among a mixture of conversations and background noises, ignoring other conversations
      • form of selective attention
  • Vision: our most dominating sense
      • height of a wave gives us its intensity (brightness)
      • length of wave gives us its hue (color)
      • longer the wavelength, the more red
      • shorter the wavelength, the more violet
    • Transduction: transforming signals into neutral impulses (Sky High); information goes from senses to the thalamus, then up to various areas of the brain
    • Young-Helmholtz Trichromatic (3 color) Theory: 3 types of cones - red, blue, green; these types of cones can make millions of combinations of colors
    • Opponent-Process Theory: sensory receptors come in pairs -
      • red/green,
      • yellow/blue
      • black/white
      • if one color is stimulated, others are inhibited
  • Hearing: height of wave gives us amplitude of sound; frequency of wave gives us pitch of sound
    • Transduction in the Ear: sound waves hit eardrum then anvil then hammer then stirrup then oval window, everything is just vibrating, then then the cochlea vibrates (cochlea is lined with mucus called basilar membranes), in basilar membrane there are hair cells, when hair cells vibrate they turn vibrations into neural impulses which are called organ of Corti, sent to thalamus up to the auditory nerve
    • Place Theories: different hairs vibrate in the cochlea when there are different pitches, same hairs vibrate when they hear high pitches and others vibrate when they hear low pitches
    • Frequency Theory: all hairs vibrate but at different speeds
    • Deafness: 1. conduction deafness - something goes wrong with sound and vibration on the way to cochlea, can replace bones or get hearing aid to help   2. nerve (sensorineural) deafness - hair cells in the cochlea get damaged, loud noises can cause this type of deafness, NO WAY to replace hairs, cochlea implant is possible
  • Smell and Taste:
    • Sensory Interaction - principle that one sense may influence another
    • Taste: we have bumps on the tongue called papillae, taste buds are located on the papillae (actually all over the mouth); sweet, salty, sour, bitter, spicy

    • Umami: flavorful, meaty, savory taste
  • Touch: receptors located in skin
    • Gate Control Theory of Pain: spinal cord contains neurological gate that blocks pain signals or allows them to pass onto the brain
    • Vestibular Sense: tells us where our body is orientated in space, our sense of balance
    • Kinesthetic Sense: tells us where our body parts are, receptors located in our muscles and joints
  • Perception: process of organizing and interpreting information, enabling us to recognize meaningful objects
    • Gestalt Philosophy: whole is greater than the sum of its parts
    • Figure-Ground Relationship: organization of visual field into object (figures) that stand out from their surroundings (ground)
    • Grouping: perceptual tendency to organize stimuli into groups that we understand
      • proximity, similarity, continuity, connectedness
    • Depth Perception: ability to see objects in 3-D although images that strike the retina are 2-D; allows us to judge distance
    • Binocular Cues: the closer an object comes to you, the greater the disparity is between the two images
    • Monocular Cues: distance cues, such as linear perspective and overlap, available to either eye alone
      • Interposition - if something is blocking our view, we perceive it is closer
      • Relative Size - if we know that 2 objects are similar in size, the one that looks smaller is farther away
      • Relative Clarity - we assume that hazy objects are farther away
      • Texture Gradient - the coarser it looks, the closer it is
      • Relative Height - things that are higher in our field of vision look farther away
      • Relative Motion - things that are closer appear to move more quickly
      • Liner Perspective - parallel lines seem to converge with distance
      • Light and Shadow - the dimmer the object appears, the further away it seems because it reflects less light
    • Motion Perception: judged mostly by size of object
      • Phi Phenomenon: illusion of movement created when two or more adjacent lights blink on and off in succession
      • Perceptual Consistency: perceiving objects as unchanging, even as the illumination and retinal images change
Thinking:
- Cognitions: term for knowing, thinking, and remembering
- Concepts: mental grouping of similar objects, events, ideas, or people; similar to Piaget's Schemas
- Prototypes: mental images or best example of categories; if new object is similar to prototype, we are able to recognize it
  • Trial and Error:
    • Algorithms - methodical, logical rule or procedure that guarantees solving a particular problem
    • Heuristics - rule-of-thumb strategy that often allows us to make judgments and solve problems efficiently; short cut (prone to error)
    • Insight - sudden and often novel realization of solution to problem; no real strategy involved
  • Obstacles to Problem Solving:
    • Confirmation Bias - tendency to search for information that confirms one's perceptions
    • Fixation - inability to see a problem from a new perspective
    • Mental Set - tendency to approach a problem in a particular way, especially if it has worked in the past; may or may not be a good thing
    • Functional Fixedness - tendency to think of things only in terms of their usual functions
  • Types of Heuristics (that often lead to error):
    • Representativeness Heuristics - rule-of-thumb for judging the likelihood of things in terms of how well they match our prototype; can cause us to ignore important information
    • Availability Heuristics - estimating the likelihood of events based on their availability in our memory; if it comes to mind easily (maybe a vivid event) we presume it is common
    • Overconfidence - tendency to be more confident than correct; to overestimate the accuracy of your beliefs and judgments
    • Framing - the way an issue is posed; can have drastic effects on your decisions and judgments
    • Belief Bias - tendency for one's preexisting beliefs to distant logical reasoning; sometimes making invalid conclusions valid or vice versa
    • Belief Perseverance - clinging to our initial conceptions after the basis on which they were formed has been discredited
    • Artificial Intelligence
Language and Thought:
- our spoken writing or gestured words and the way we combine them to communicate meaning
  • Phonemes: in a spoken language, the smallest distinctive sound unit
    • Example: the word chug has 3 phonemes: ch, u , g
  • Morphemes: in a language, the smallest unit that carries the meaning
    • Example: it can be a word or a part of a word (prefix/suffix)
  • Grammar: system of rules in a language that enables us to communicate and understand others
  • Semantics: set of rules by which we derive meaning in a language
    • Example: adding "-ed" at the end of words makes it past tense
  • Syntax: rules for combining words into grammatically sensible sentences

  • Language Development -
    • Babbling Stage: starting at 3 - 4 months, infant makes spontaneous sounds; not limited to the phonemes of the infant's household language
    • One-word Stage: 1 - 2 years old, uses one word to communicate big meanings
    • Two-word Stage: at age 2, uses two words to communicate meanings, which are called Telegraphic Speech
  • developed by Skinner - explained language development through social learning theory
    • Chomsky - acquire language quickly for it to be learned; "learning box" inside leads that enables us to learn any human language
  • Language Influence Thinking?
    • Whorf's Linguistic Relativity: idea that language determines the way we think (not vice versa)
  • Number of Language Make us Think Different?
    • Thinking without Language: we can think in words, but more often in mental pictures
  • Animals Think?
    • Kohler's Chimpanzees: Kohler exhibited that Chimps can problem solve
Intelligence:
- ability to learn from experience, solve problems, and use knowledge to adapt to new situations; socially constructed thus can be culturally specific
  • Factor Analysis: statistical procedures that identifies clusters of related items on a test; Charles Spearman used it to discover General Intelligence
  • Multiple Intelligence: Howard Gardner agree with Spearman's General Intelligence and came up with Multiple Intelligence; idea that came about by studying savants (a condition where a person has limited mental abilities but exceptional in one area)
    • Visual/Spatial
    • Verbal/Linguistic
    • Logical/Mathematics
    • Bodily/Kinesthetic
    • Musical/Rhythm
    • Interpersonal
    • Intrapersonal
    • Natural
  • Sternberg's 3 Aspects of Intelligence:
    1. Analytical (academic problem solving)
    2. Creative (generating novel ideas)
    3. Practical (required for everyday tasks where multiple solutions exists)
  • Emotional Intelligence: ability to perceive, express, understand, and regulate emotions
  • Brain Functions and Intelligence: higher preforming brains use less active than lower preforming brains (less glucose used); neurological speed is a bit quicker
  • Assessing Intelligence:
    • Alfred Binet and Theodore Simon tried to figure out the concept of Mental Age (what a person of a particular age should know)
    • discovered that by discovering someone's Mental Age they can predict future performance
    • Terman using this study came up with the IQ test (aka the Stanford-Binet Test)
  • Modern Tests of Mental Abilities:
    • Wechsler's Adult Intelligence Scale (WAIs) - consists of 11 subtests and cues us in strengths by using Factor Analysis
  • Aptitude v.s Achievement Tests:
    • Aptitude - a test designed to predict a person's future performance; the ability for that person to learn (Example: SATs)
    • Achievement - a test designed to assess what a person has learned (Example: AP tests)
    • tests must be Standardized, Reliable, and Valid
      • Standardized: test must be pre-tested to a representative sample of people and form a normal distribution or bell curve
        • Flynn Effect - intelligence test performance has been rising
      • Reliable: extent which a test yields consistent results over time; split halves or test-reset method
      • Validity: extent to which a test measures what it is supposed to measure
        • Content Validity - does the test sample a behavior of interest
        • Predictive Validity - does the test predict future behavior
  • Intelligence Over Time: at the age of 3, a child's IQ can predict adolescent IQ scores depending on the type of intelligence that's crystallized or fluid

1 comment:

  1. The video ultimately helped wrap my head around the idea of what perception really is. At first, the two (perception and sensation) kind of confused me, but that really cleared it up for me. other than that, nice organization on your blog! Easy to find words I need to know.

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