Psychology Unit V: Sensation & Perception

SENSATION & PERCEPTION

Sensation

• window into the world
• process by which our sensory receptors and nervous system receive stimulus from the environment 
• processing of stimuli

Perception

• interpret what comes into window
• essentially an interpretation and elaboration of sensation
• organizing and interpreting sensory information, enabling us to recognize meaningful objects and events

Visual Capture

• tendency for vision to dominate other senses

Gestalt Psychology

• "means an organized whole"
• these psychologists emphasize our tendency to integrate pieces of info into meaningful wholes

Gestalt Philosophy

• whole is greater than the sum of its parts

Figure - Ground Relationship

• the organization of the visual field into objects (figures) that stand out from their surroundings (ground)

Grouping

• perceptual tendency to organize stimuli into groups that we understand

1. Proximity: nearby objects together
2. Similarity: similar figures together
3. Continuity: continuous patterns together
4. Connectedness: uniform & linked figures group together

Depth Perception

• ability to see objects in 3D although images that strike the retina are 2D
• allows us to judge distance

Binocular Cues

• depth cues that depend on two eyes
• Retinal Disparity: binocular cue for seeing depth
• the closer an object come to you the greater the disparity is between two images

Monocular Cues

• depth cues that depend on one eye
• Interposition: if something is blocking our view, we perceive it as closer 
• Relative Size: if we know two objects are similar in size, the one that looks smaller is further away
• Relative Clarity: we assume hazy objects are farther away

1. Texture Gradient: the coarser it is, the closer it is
2. Relative Height: things higher in our field of vision, look farther away
3. Relative Motion: things closer look like the move more quickly
4. Linear Perspective: parallel lines seem to converge at a distance
5. Light & Shadow: dimmer objects appear farther away because they reflect less light

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 illumination and retinal images change

Sensation & Perception

Bottom Up vs. Top Down Processing

• Bottom Up: analysis that begins with the sense receptors and works up to the brain's integration of sensory information
• Top Down: information processing guided by higher - level mental processes, when we construct perceptions drawing on our experience and expectations

Absolute Threshold

• minimum stimulation needed to detect a stimulus 50% of the time

Difference Threshold

• the difference that a person can detect between two stimuli 
• aka: Just Noticeable Difference

Weber's Law

• idea that to perceive a difference between two stimuli, they must differ by a constant percentage , not a constant amount. 

Signal Detection Theory

• predicts how we detect a stimulus amid other stimuli
• assumes that we do not have an absolute threshold
• we detect stuff based on experience, motivation, and fatigue level.

Subliminal Stimulation

• below one's absolute threshold for conscious awareness

Transduction

• transforming signals into neural impulses 
• information goes from the senses to the thalamus, then to various areas of the brain

Sensory Adaptation

• diminished sensitivity as a result of constant stimulation

Selective Attention

• focusing of conscious awareness on a particular stimuli

Cocktail Party Effect

• ability to listen to one voice among many

Pheromones

• chemical messengers that are picked up through our sense of smell

Touch

• receptors located in skin
• Gate Control Theory of Pain: where nervous system blocks or allows pain signals to pass to the brain

Vestibular Sense

• tells where the body is oriented in space
• sense of balance

Kinesthetic Sense

• tells where body parts are 
• receptors located in muscles and joints

Vision

Transduction

• conversion of one form of energy to another

Wavelength

• distance from the peak of one light wave to the peak of the next
• distance determines the hue (color) of the light we perceive

Intensity

• amount of energy in a light wave 
• determined by height of a wave
• the higher the wave, the more intense light is

Parallel Processing

• processing of several aspects of a problem simultaneously 

Young Helmholtz Trichromatic Theory

• three color theory
• realized that any color can be created by combining the light waves of three colors (primary) 
• red, green, and blue
• most color blind people lack cone receptor cells for one or more primary colors

Rods

• facilitate black & white vision

Cones

• facilitate color vision

Opponent Process Theory

• we can't see certain colors together in a combination

Hearing (Audition)

Frequency

• number of complete wavelengths that pass through a point at a given time
• determines pitch of a sound

Amplitude

• how loud the sound is
• the higher the crest of the wave is, the louder the sound is
• measured in decibels

Helmholtz's Place Theory

• we hear different pitches because different sound waves trigger activity at different places
• along the cochlea's basilar membrane 

Frequency Theory

• we sense pitch by the basilar membrane vibrating at the same rate as the sound

Hearing Loss

• Conduction: caused by damage to the mechanical system of ear
• Sensorineural: damage to cochlea's receptor cells or to auditory nerves

Smell & Taste

• chemical senses

Sensory Interaction

• the principle that one's senses many influence another

Papillae 

• those bumps on our tongue
• help grip food while chewing
• contain taste buds

Psychology Unit VI: Sleep Disorders

SLEEP DISORDERS

Insomnia

• recurring problems in falling asleep or staying asleep

Narcolepsy

• uncontrollable sleep attacks 
• lapses directly into REM sleep (stress or joy)

Sleep Apnea

• temporary cessations of breathing during sleep and momentary awakening

Night Terrors

• high arousal and appearance of being terrified
• stage 4, not REM, not often remembered

Sleepwalking

• somnambulism
• most often occurs during deep non - REM sleep (stage 3 or 4) early in the night

Psychology Unit VI: Stages of Sleep

STAGES OF SLEEP

Stage One

• kind of awake and asleep
• a few minutes
• eyes roll slightly
• brain produces Theta waves

Stage Two

• "baseline" of sleep
• part of a 90 minute cycle and occupies about 45 - 60% of sleep
• more Theta waves get progressively slower
• begin to show sleep spindles

Stages Three to Four 

• slow wave sleep
• produce Delta waves
• if awoken, can be groggy
• may last 15 - 30 minutes 
• "Delta" sleep is deepest stage of sleep
• restore body's growth hormones and good health

Stage Five REM Sleep

• Rapid Eye Movement
• called Paradoxical Sleep
• brain is active
• dreams occur
• body is essentially paralyzed 
• composes about 20 - 25% of a normal night's sleep
• quicken breathing, heart rate, and brain waves
• vivid dreams can occur
• from REM sleep, you go back to Stage Two

Psychology Unit VI: States of Consciousness

STATES OF CONSCIOUSNESS 

Sleep

• state of consciousness
• we are less aware of our surroundings

Levels (three)

• conscious
• subconscious
• unconscious

Biological Rhythms

• annual cycles: seasonal variations
• 28 days: menstrual cycle
• 24 hour: our circadian rhythm
• 90 minutes: sleep cycles

Circadian Rhythm

• our 24 hour biological clock
• our body temperature and awareness changes throughout the day

Sleep Stages

• five stages 
• takes about 90 - 100 minutes to pass through five stages 
• brain's waves will change according to sleep stage you're in 
• first four stages known as NREM sleep
• fifth stage is called REM sleep

Psychology Unit V: Learning

LEARNING 

Three Main Types of Learning

• Conditioning: classical & operant
• Learning: observational & latent
• Learning: abstract & insight

Associative Learning

• learning that certain events occur together

Classical Conditioning

• acquisition
• extinction
• spontaneous recovery
• generalization
• discrimination

Conditioned Stimulus

• an originally irrelevant stimulus, that after association with the UCS, comes to trigger a response

Conditioned Response

• the learned response to a previously neutral stimulus

Unconditioned Stimulus 

• naturally and automatically triggers a response

Unconditioned Response

• the unlearned, naturally occurring response to the the UCS

Acquisition

• initial stage of learning
• phase where neural stimulus is associated with the UCS so that the neutral stimulus comes to elicit the CR (becoming the CS)
• Cs is before UCS and they occur together in timing

Extinction

• diminishing of a conditioned response 
• will eventually happen when the UCS does not follow the CS 

Spontaneous Recovery

• the reappearance after a rest period, of an extinguished conditioned response 

Generalization

• tendency once a response has been conditioned for stimuli similar to the CS to elicit similar responses

Discrimination

• learned ability to distinguish between a CS and other stimuli that does not signal UCS 

Mood - Congruent Theory

• tendency to recall experiences that are consistent with one's current mood (good or bad)
• depressed = sad memories recalled
• moods affect the way you interpret other people's behavior

Operant Conditioning

• type of learning in which behavior is strengthened if followed by reinforcement or diminished if followed by punishment

Classical vs. Operant

• both use acquisition, discrimination, spontaneous recovery, generalization, and extinction
• classical conditioning is automatic (respondent behavior) 
• operant conditioning involves behavior where one can influence their environment with behaviors which have consequences (operant behavior) 

Edward Thorndike

• Law of Effect: rewarded behavior is likely to recur (operant behaviors)

B.F. Skinner

• Operant Conditioning 

Shaping

• reinforcers guide behavior closer and closer towards a goal
• procedure in operant conditioning

Reinforcer

• event that strengthens the behavior it follows
• two types: positive and negative

Positive Reinforcement

• strengthens a response by presenting a stimulus after a response

Negative Reinforcement 

• strengthens a response by reducing or removing an aversive stimulus 

Primary Reinforcer

• innately reinforcing stimulus

Conditioned (Secondary Reinforcer)

• stimulus that gains its reinforcing power through its association with a primary reinforcer

Continuous Reinforcement

• reinforces the desired response every time it occurs

Partial Reinforcement

• reinforces a response only part of the time 
• acquisition is slower
• greater resistance to extinction

Fixed - Ratio Schedule

• reinforces a response only after a specified number of responses 

Variable - Ratio Schedule

• schedule of reinforcers that reinforces a response after an unpredictable number of responses

Fixed - Interval Schedule

• schedule of reinforcement that reinforces a response only after a specified time has elapsed

Variable - Interval Schedule

• that reinforces a response at unpredictable time intervals 

Punishment

• meant to decrease a behavior
• positive punishment: addition of something unpleasant 
• negative punishment (omission training): removal of something pleasant 
• works best if harsh or when done immediately after behavior

Token Economy

• every time a desired behavior is performed, a token is given
• trade token for prizes (reinforcers) 
• used in homes, prisons, mental places, and schools

Observational Learning

• Bandura & BOBO Doll
• we learn through modeling behavior from others 
• operant learning + operant conditioning  = social learning theory

Insight Learning

• Wolfgang Kohler & Chimpanzees
• some animals learn through the "ah ha" experience

Latent Learning

• Edwards Toleman
• sometimes learning is not immediately evident 
• hidden

Psychology Unit VI: Memory

MEMORY

• the persistence of learning over time through the storage and retrieval of information

Process

• encoding: processing of information into the memory system, getting information out of our heads
• storage: retention of encoded material over time
• retrieval: getting the information out of memory storage

Ways to Encode

• automatic: unconscious encoding of incidental information, encode space, time, words, and meaning without information, things can become automatic with practice
• effortful: requires attention and conscious effort, rehearsal is the most common effortful processing technique, through effortful processing what was effortful becomes automatic

Recall vs. Recognition

• recall: you must retrieve information from memory, an example is fill - in - the - blank
• recognition: identify the target from possible targets, an example is multiple choice

Flashbulb Memory

clear moment of an emotionally significant moment or event

Types of Memory

• sensory
• short - term
• long - term

Sensory

• immediate, initial recording of sensory information in the memory system
• stored for an instant, most gets unprocessed 
• lasts half a second for visual
• lasts 2 - 4 seconds for auditory 
• capacity of storage is large
• any information not transferred is lost

Short - Term Memory

• holds a few items briefly 
• remember seven digits at a time
• information will be stored into long - term or forgotten
• aka: working memory
• limited capacity
• 3 - 12 seconds
• digits are more easily remembered than letters
• has three parts: audio, visual, and integration of both (controls where attention lies)

Long - Term Memory

• permanent and limitless storehouse

Encoding

• next - in - line effect: we seldom remember what the person has just said or done if we are next
• information minutes before sleep is seldom remembered; in hours before sleep, it is well remembered
• taped information played while asleep is registered by ears, but we do not remember it 

Spacing Effect

• we encode better when we study or practice over time

Serial Positioning Effect

• our tendency to recall best the first and last items in a list

Types of Encoding

• Semantic: meaning, like meaning of words
• Acoustic: sound, especially the sounds of words
• Visual: picture images

Self - Reference Effect

• we remember things when they are used to describe ourselves
• how we encode meaning very well

Tricks to Encode

• imagery: mental pictures

Chunking

• organize items into familiar, manageable units
• often it will occur automatically 

Iconic Memory

• momentary sensory memory of visual stimuli, a photo like quality lasting about a second
• we also have an echoic memory for auditory stimuli

Storing Memory

• long - term potentiation: long - lasting enhancement in signal transmission between two neurons, results in stimulating them synchronously
• they learn to fire together and get better at it...creating a memory 

Hippocampus

• damage disrupts memory
• right is visual and locations
• left is verbal

Types of Retrieval Failure

• proactive interference: disruptive effect of prior learning on the recall of new information
• retroactive interference: disruptive effect of new learning on the recall of old information

Motivated Forgetting

• repression: basic defense mechanism that banishes anxiety - arousing thoughts, feelings, and memories from conscious

Déjà Vu

• eerie sense you have experienced something before
• what is occurring is that the current situation cues past experiences that are very similar to the present one - you mind gets confused

Psychology Unit V: Intelligence

INTELLIGENCE

• the ability to learn from experience, solve problems, and use knowledge to adapt to new situations

Multiple Intelligences

• idea that studying savants
• savants: when a person has limited mental ability, but is exceptional in one area

Gardner's Multiple Intelligences 

1. visual/spatial
2. verbal/linguistic
3. logical/mathematical
4. bodily/kinesthetic
5. musical/rhythmic
6. interpersonal
7. intrapersonal
8. natural

Factor Analysis

• statistical procedure that identifies clusters of related items on a test

Gardner Simplified

• analytical: academic & problem solving
• creative: generating novel ideas
• practical: required for everyday tasks where multiple solutions exist

Emotional Intelligence

• ability to perceive, express, understand, and regulate emotions

How Do We Assess Intelligence?

• Alfred Binet & Theodore Simon
• mental age: what a person of a particular age should know
• discovering mental age can predict future performance
• use test to help children, not label them

Brain Size and Intelligence, Is There a Link?

• small + .15 correlation between head size and intelligence scores (relative to body size)
• using a MRI we found + .44 correlation with brain size and IQ score

IQ Test

• Terman
• IQ = (mental age / chronological age) X 100

Brain Function & Intelligence

• higher performing brains use less active than lower performing brains (use less glucose)
• neurological speed is also a bit quicker

Wechsler Adult Intelligence Scale (WAIS)

• consists of 11 subtests and cues us in to strengths by using factor analysis

Standardization

• the test must be pre - tested to a representative sample of people and form a normal distribution or bell curve

Aptitude vs. Achievement Tests

• Aptitude: a test designed to predict a person's future performance, the ability for that person to learn
• Achievement: a test designed to assess what a person has learned

Flynn Effect

• intelligence test performance has been rising

How Do We Conduct Intelligence Tests?

• they must be standardized, reliable, and valid

Validity

• the 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

Test Bias?

• do discriminate
• some argue that their sole purpose is to discriminate

Psychology Unit V: Thinking

THINKING

Prototypes

• best example of a category

Cognition

• thinking, knowing, and remembering

Algorithms

• methodical, logical, rule or procedure that guarantees solving a problem

Concepts

• mental grouping of similar objects, events, ideas, or people
• similar to schemas

Heuristics

• a rule - of - thumb strategy that often allows us to make judgments and solve problems efficiently 
• a short cut that could be prone to errors

Representative Heuristics

• rule of thumb for judging the likelihood of things in terms of how well they match our prototype
• can cause is to ignore important information

Availability Heuristics

• estimating the likelihood of events based on their availability in our memory
• if it comes to the mind easily we presume it is common

Insight

• a sudden realization of the solution to a problem

Fixation

• the inability to see a problem from a new perspective

Confirmation Bias

• a tendency to search for information that confirms one's preconceptions

Overconfidence

• tendency to be more confident that correct
• to overestimate the accuracy of your beliefs and judgement

Framing

• the way an issue is posed
• it can have drastic effects on your decisions and judgements

Belief Bias

• tendency for one's preexisting beliefs to distort logical reasoning
• sometimes making invalid conclusions valid or vice versa

Belief Perseverance

• clinging to your initial conceptions after the basis on which they were formed has been discredited

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

• the tendency to think of thing only in terms of their usual function

Psychology Unit V: Language & Thought

LANGUAGE & THOUGHT 

Language

• our spoken, written, or gestured words
• the way we combine them to communicate meaning 

Phonemes

• in a spoken language, smallest distinctive sound unit

Morphemes

• in a language, the smallest unit that carries meaning
• word or parts of a word 
• prefix or 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

Syntax

• rules for combining words into grammatically sensible sentences

Language Development

• Babbling Stage: starting at 3 - 4 months, spontaneous sounds, not limited to phonemes of infant's household language
• One Word Stage: 1 - 2 years old, one word for big meanings 
• Two Word Stage: at 2 years old, two words to communicate meanings - called telegraphic speech

Skinner

• we can explain language development through social learning theory

Chomsky

• we acquire language too quickly for it to be learned 
• "learning box" inside our heads that enable us to learn any human language

Whorf's Linguistic Relativity

• idea that language determines the way we think (not vice versa)

Macroeconomics Unit VII: Absolute Advantage & Comparative Advantage

ABSOLUTE ADVANTAGE & COMPARATIVE ADVANTAGE

Absolute Advantage

• individual: exists when a person can produce more of a certain good or service than someone else can in the same amount of time
• national: exists when a country can produce more of a good or service than another country can in the same time period

Comparative Advantage

• individual/ national: exists when an individual or nation can produce a good or service at a lower opportunity cost than can another individual or nation
• input: what can be produced using the least amount of resources, land, or time; chosen item over the forgone item
• output: production, lowest opportunity cost; what the give up over what is produced

Macroeconomics Unit VII: Balance of Payments

BALANCE OF PAYMENTS

• measures the money inflows and money outflows between the U.S. qand the rest of the world
• outflows from the U.S. are debits
• inflows are credits

Balance of Accounts

• three parts
• current account 
• capital/financial account
• official reserves

Double Entry Bookkeeping

• every transaction in the balance of payments is recorded twice in accordance with standard accounting practice

Current Account

• balance of trade or net exports
• (exports of goods and services - imports of goods and services)
• net foreign income: (income earned by U.S. owned foreign assets - income paid to foreign held U.S. assets)
• net transfers (unilateral): foreign aid is a debit to the current account

Capital/ Financial Account

• balance of capital ownership
• includes the purchase of both real and financial assets
• direct investment in the U.S. is a credit to the capital account 
• direct investment by U.S. firms/individual in a foreign country are debits to the capital account
• purchase of foreign financial assets by a foreign country represents a credit to the capital account

Relationship Between Current and Capital/Financial Account

• should zero out each other
• if current account has a negative balance (deficit) then the capital account should have a positive balance (surplus)

Official Reserves

• foreign currency holding of U.S. Federal Reserve System 
• with the balance of payments surplus, the FED accumulates foreign currency and debits the balance of payments
• with balance of payments deficit, the FED depletes its reserves of foreign currency and credits balance of payments 
• zero out the balance of payments
• active vs. passive: the U.S. is passive in its use of official reserves and does not seek to manipulate the exchange rate

Balance of Trade

• (goods and services exports - goods and services imports)
• surplus: imports > exports
• deficit: exports > imports

Current Account

• (balance of trade + net investments + net transfers)

Capital Account

• (foreign purchases of U.S. assets + U.S. purchase of assets abroad)

Official Reserves

• (capital account balance + current account balance)

Foreign Exchange (FOREX)

• buying or selling of currency
• exchange rate (e) is determined in the foreign currency markets
• exchange rate is price of a currency

Four Tips

• change the demand line on one currency graph and the supply line on the other currency's graph
• move the lines of the two currency graphs in the same direction (right or left) 
• if demand on one graph increases, supply on the other will also increase
• If demand moves left, supply moves left on other graph

Changes in Exchange Rates

• exchange rates (e) are a function of the supply and demand for currency
• increase in supply of currency makes it cheaper to buy one unit of it, vice versa for a decrease in supply
• increase in demand of currency will make buying one unit more expensive, vice versa for decrease in demand

Determinants of Exchange Rate

• Consumer Tastes
• Relative Economy
• Relative Price Level
• Speculation

Macroeconomics Unit V & VI: Phillip's Curve

PHILLIP'S CURVE

Short Run Phillip's Curve

• time too short for wages to adjust to the price level
• workers may not be aware of changes in their real wages due to inflation and have adjusted their labor supply decisions and wage demands accordingly
• nominal wages: amount of money received per hour per day or per year
• sticky wages: nominal wage level that is set according to an initial price level and does not vary

LRAS Assumptions

• time not long enough for ages to adjust to price level
• price level and wage level is flexible
• changed in wage level & price level offset each other

Demand Pull

• AD increases
• AS decreases

Cost - Push

• AD increases
• AS decreases

Phillip's Curve

• represents relationship between unemployment and inflation
• occurs at natural rate of unemployment
• represented by a vertical line
• no trade off between unemployment and inflation in the long run
• economy produces at full employment level 
• only shift if LRAS curve shifts

LRAS Shift

• technological and economic growth

NRAU

• frictional
• seasonal
• structural

LPRC

• major assumptions: more workers benefits create increased natural rates and fewer create lower rates

SRAS

• trade off between inflation and unemployment that only occurs in short run
• when inflation increases, unemployment decreases
• inverse: high inflation = low unemployment

SPRC

• has relevance to Okun's Law
• since wages are sticky, inflation changes move points on the SRPC
• if inflation persists and expected rate of inflation rises, then entire SRPC moves upward which causes a situation called stagflation
• if inflation expectations decrease due to new technology or economic growth, then SRPC moves downward

AS Shocks

• cause both rate of inflation and unemployment to increase 

Supply Shock

• rapid increase in resource cost

Misery Index

• combination of inflation and unemployment in any given year
• single digit misery is good

Long Run Phillips Curve

• because LPRC exists at natural rate of unemployment, structural changes in the economy that affect unemployment will also cause LPRC to shift
• AD along the curve
• AS on curve

Supply Side Economics

• also called Reaganomics 
• belief that AS curve will determine levels of inflation, unemployment, and economic growth
• to increase the economy, would shift AS curve to the right
• economists focus on marginal tax rate
• decrease taxes or incentives for a business to invest in economy
• decrease taxes or incentives for workers to work hard, thereby becoming more productive 
• decrease taxes or incentives for people to increase savings and therefore create lower interest rates, which causes an increase in business investment
• support policies that promote GDP growth by arguing that high marginal tax rates along with current system of transfer payments such as unemployment compensation or welfare programs provide disincentives to work, invest, innovate, and undertake entrepreneural ventures. 

Marginal Tax Rate

• amount paid on last dollar earned or each additional dollar earned

Laffer Curve

• trade off between tax rates and government revenue
• used to support supply side argument
• as tax rates increase from zero, tax revenue increases from zero to some max level and then declines

Criticisms

• research suggests that impact of tax rates on incentives to work, save, and invest are small
• tax cuts also increase demand which can fuel inflation, thus creating a situation where demand exceeds supply 
• where economy located on curve is difficult to determine