Psychology Exam III - Cognitive and Developmental Psychology

Sensation

Sensation

simple stimulation of a sense organ; basic registration of light, sound, pressure, odor, or taste as parts of your body interact with the physical world

Perception

the organization, identification, and interpretation of a sensation in order t form a mental representation; how sensation is registered

Transduction

when sense receptors convert physical signals from the environment into neural signals that are sent to the central nervous system

Sensory adaptation

sensitivity to prolonged stimulation tends to decline over time as an organism adapts to current (unchanging) conditions

Psychophysics

methods that systematically relate the physical characteristics of a stimulus to an observer’s perception

Example for a psychophysics experiment

researchers ask people to decided whether or not they see a faint spot of light, and the intensity of the light is changed systematically. Responses of the observer are recorded as a function

Absolute threshold

minimal intensity needed to just barely detect a stimulus in 50% of the trials

Threshold

a boundary

Approximate sensory threshold for vision

a candle flame 30 miles away on a clear, dark night

Approximate sensory threshold for hearing

a clock’s tick 20 feet away when all is quiet

Approximate sensory threshold for touch

a fly’s wing falling on the cheek from 1 centimeter away

Approximate sensory threshold for smell

a single drop of perfume diffused through an area equivalent to the volume of six rooms

Approximate sensory threshold for taste

a teaspoon of sugar dissolved in two gallons of water

Sensitivity

how responsive we are to faint stimulus

What is absolute threshold useful for assessing?

sensitivity

Acuity

how well we can distinguish two very similar stimuli

Just noticeable difference (JND)

the minimal change in a stimulus that can just barely be detected; not a fixed quality as it depends on the particular sense being measured and the intensity of the original stimulus

Standard (S)

fixed intensity

Relationship for any sensory domain

the ratio between the JND and the standard stimulus is a constant value except when the standard takes extreme values (e.g., is hard to perceive, or is overwhelming)

Weber’s law

for every sense domain, the change in a stimulus that is just noticeable is a constant proportion despite variation in intensities

Example of Weber’s law

if you picked up a 1-ounce envelope, then a 2-ounce envelope, you’d probably notice the difference between them. But if you picked up a 20-pound package, then a 20-pound, 1-ounce package, you’d probably detect no difference at all between them.

Noise

all the other stimuli coming from the internal and external environment

Signal detection theory

the response to a stimulus depends both on a person’s sensitivity to the stimulus in the presence of noise and on a person’s decision criterion; an approach to psychophysics

Parallel processing

the brain’s capacity to perform multiple activities at the same time

Illusory conjunction

perceptional mistake whereby the brain incorrectly combines features from multiple objects

Feature-integration theory

focused attention is not required to detect the individual features that make up a stimulus but it is required to bind those individual features together

Attention

the active and conscious processing of particular information

Perceptual constancy

even as aspects of sensory signals change, perception remains constant

Conceptual knowledge

the rich store of facts and other meaningful knowledge we have about a familiar object; when we perceive an object, we don’t merely recognize what it looks like, but we understand what it is — its characteristics and significance to our behavior

Perceptual organization

process of grouping and segregating features to create whole objects organized in meaningful ways

Concept

a mental representation that groups or categorizes shared features of related objects, events, or other stimuli

Necessary condition

something that must be true of the object in order for it to belong to the category

Sufficient condition

something that, if it is true of the object, proves that it belongs to the category

Prototype theory

the concept that we classify new objects by comparing them to the “best” or “most typical” member of a category

Exemplar theory

we make category judgements by comparing a new instance with stored memories of other instances of the category

Category-specific deficit

a neurological syndrome characterized by an inability to recognize objects that belong to a particular category, even when the ability to recognize objects outside the category is undisturbed

Rational choice theory

the classical view that we make decisions by determining how likely something is to happen, judging the value of the outcome, and then multiplying the two

Availability heuristic

A rule of thumb that items that are more readily available in memory are judged as having occurred more frequently

Heuristic

fast and efficient strategy that may facilitate decision making but does not guarantee that a solution will be reached

Why does our availability heuristic affect our estimates?

Memory strength and frequency of occurrence are directly related

Algorithm

a well-defined sequence of procedures or rules that guarantees a solution to a problem

Base rate

the existing probability of an event

Representativeness heuristic

A mental shortcut that involved making a probability by comparing an object or event with a prototype of the object or event

Conjunction fallacy

thinking that two events are more likely to occur together than either individual event alone because people rely on the representativeness heuristic

Framing effects

when people give different answers to the same problem depending on how the problem is framed

Sunk-cost fallacy

a framing effect in which people make decisions about a current situation on the basis of what they have previously invested in the situation

Optimism bias

people believe that, compared with other individuals, they are more likely to experience positive events and less likely to experience negative events in the future

Prospect theory

people choose to take on risks when evaluating potential losses and to avoid risks when evaluating potential gains; assumes that, in evaluating choices, people compare them with a reference point

Certainty effect

An assumption suggesting that when making decisions, people give greater weight to outcomes that are a sure thing

Memory

the ability to store and retrieve information over time

Encoding

the process of transforming what we perceive, think, or feel into an enduring memory

Storage

the process of maintaining information in memory over time

Retrieval

the process of bringing to mind information that has been previously encoded and stored

Semantic encoding

the process of relating new information in a meaningful way to knowledge that is already stored in memory

Visual imagery encoding

the process of storing new information by converting it into mental pictures

Organizational encoding

the process of categorizing information according to the relationship among a series of items

Mnemonics

encoding strategies that improve subsequent retrieval

Sensory memory

a type of storage that holds sensory information for a few seconds or less

Iconic memory

a fast-decaying store of visual information

Echoic memory

a fast-decaying store of auditory information

Short-term memory

a type of storage that holds nonsensory information for more than a few seconds but less than a minute

Rehearsal

the process of keeping information in short-term memory by mentally repeating it

Serial position effect

the observation that the first few and last few items in a series are more likely to be recalled than the items in the middle

Primacy effect

enhanced recall of the most first few items

Recency effect

enhanced recall of the last few items

How many meaningful items can short-term memory hold at once?

about 7

Chunking

combing small pieces of information into larger clusters or chunks that are more easily held in short-term memory

Working-memory

active maintenance of information in short-term storage

Long-term memory

type of storage that holds information for hours, days, weeks, or years

Anterograde amnesia

the inability to transfer new information from the short-term store into the long-term store

Retrograde amnesia

the inability to retrieve information that was acquired before a particular date, usually the date of an injury or surgery

Consolidation

the process by which become stable in the brain

Reconsolidation

consolidating memories again because memories can become vulnerable to disruption when they are recalled

Long-term potentiation (LTP)

a process whereby repeated communication across the synapse between neurons strengthens the connections, making further communication easier

Retrieval cue

external information that is associated with stored information and helps bring it to mind

Encoding specificity principle

a retrieval cue can serve as an effective reminder when it helps re-create the specific way in which information was initially encoded

State-dependent retrieval

the process whereby information tends to be better recalled when the person is in the same state during encoding and retrieval

Transfer-appropriate processing

the idea that memory is likely to transfer from one situation to another when the encoding and retrieval contexts of the situations match

Retrieval-induced forgetting

a process by which retrieving an item from long-term memory impairs subsequent recall of related items

Intelligence

the ability to use one’s mind to solve novel problems and learn from experience

Mental age

someone’s mental level expressed through age

Ratio IQ

a metric obtained by dividing a child’s mental age by the child’s physical age and then multiplying the quotient by 100

What is the problem with ratio IQ?

intelligence increases dramatically in the first decade or so life and then levels off but the ratio IQ for a 7-yr-old who performs like an 14-yr-old is the same as a 20-yr-old who performs like a 40-yr-old → adults of different ages don’t have remarkably different intellectual capacities

Deviation IQ

a metric obtained by dividing an adult’s test score by the average adult’s test score and then multiplying the quotient by 100

How is the deviation IQ different from the ratio IQ?

instead of comparing a person’s mental age to their own physical age, the deviation IQ score compares their performance to the performance of others

Positive manifold

the fact that a person’s performances on a variety of tests tend to be positively correlated

Two-factor theory of intelligence

a person’s performance on a test is due to a combination of general cognitive ability and specific abilities that are unique to the test

g

general cognitive ability

s

specific abilities

Confirmatory factor analysis

mathematical technique that showed the correlations between scores on different tests are best described by a three-level hierarchy with a general factor at the tope, set of “group factors” in the middle, and some specific factors at the bottom

John Carroll’s eight middle-level abilities

memory and learning, visual perception, auditory perception, retrieval ability, cognitive speediness, processing speed, crystallized intelligence, and fluid intelligence

Crystallized intelligence

ability to apply knowledge that was acquired through experience; generally measured by tests of vocabulary and factual information

Fluid intelligence

ability to solve and reason about novel problems; generally measured by tests that present people with abstract problems in new domains that must be solved under time pressure

Analytic intelligence

the ability to identify and define problems and to find strategies for solving them

Creative intelligence

the ability to generate solutions that other people do no

Practical intelligence

the ability to implement solutions in everyday settings

Emotional intelligence

the ability to reason about emotions and to use emotions to enhance reasoning

What is the estimated role that genes play in producing intelligence?

the role is quite large according to correlational studies between the IQs of genetically identical twins who were raised in different households are more similar to each other than the IQs of biologically unrelated children who were raised in the same household

Why do our genes hold a role in producing intelligence?

intelligence is influenced by the structure and function of the brain, and the structure and function of the brain are influenced by the genes

Heritability coefficient

a statistic that describes the proportion of the difference between two or more people’s IQ scores that can be explained by differences in their genes; usually somewhere between 0.5 and 0.7 → ~ 50% to 70% of the differences between people’s IQ scores is due to the genetic differences between those people