Models of Memory

Information Processing Model

• Information processing model: compares our mind to a computer.

• Encoded when our sensory receptors send impulses that are registered by neurons in our brain, similar to getting electronic information into our computer’s CPU (central processing unit) by keyboarding.

• Store and retain the information in our brain for some period, ranging from a moment to a lifetime, similar to saving information in our computer’s hard drive.

• Retrieved upon demand when it is needed, similar to opening up a document or application from the hard drive.

• Donald Broadbent: modeled human memory and thought processes using a flowchart that showed competing information filtered out early, as it is received by the senses and analyzed in the stages of memory.

• Attention: is the mechanism by which we restrict information.

  • Trying to attend to one task over another requires selective or focused attention.

  • We have great difficulty when we try to attend to two complex tasks at once requiring divided attention, such as listening to different conversations or driving and texting.

• According to Anne Treisman’s feature integration theory, you must focus attention on complex incoming auditory or visual information in order to synthesize it into a meaningful pattern.

Levels-of-Processing Model

• According to Fergus Craik and Robert Lockhart’s levels-of-processing theory: how long and how well we remember information depends on how deeply we process the information when it is encoded.

• Shallow processing: we use structural encoding of superficial sensory information that emphasizes the physical characteristics, such as lines and curves, of the stimulus as it first comes in.

• Semantic encoding: associated with deep processing, emphasizes the meaning of verbal input.

• Deep processing: occurs when we attach meaning to information and create associations between the new memory and existing memories (elaboration).

Three-Stage Model

• Atkinson–Shiffrin three-stage model of memory: describes three different memory systems characterized by time frames: sensory memory, short-term memory (STM), and long-term memory.

• Sensory memory: visual or iconic memory that completely represents a visual stimulus lasts for less than a second, just long enough to ensure that we don’t see gaps between frames in a motion picture.

• Auditory or echoic memory lasts for about 4 seconds, just long enough for us to hear a flow of information.

• Selective attention: focusing of awareness on a specific stimulus in sensory memory, determines which very small fraction of information perceived in sensory memory is encoded into short-term memory.

• Automatic processing: is unconscious encoding of information about space, time, and frequency that occurs without interfering with our thinking about other things.

• Parallel processing: a natural mode of information processing that involves several information streams simultaneously.

• Effortful processing: is encoding that requires our focused attention and conscious effort.

Short-Term Memory

• Short-term memory (STM): can hold a limited amount of information for about 30 seconds unless it is processed further.

• Chunk: can be a word rather than individual letters or a date rather than individual numbers.

• Alan Baddeley’s: working memory model involves much more than chunking, rehearsal, and passive storage of information.

• Working memory model: is an active three-part memory system that temporarily holds information and consists of a phonological loop, visuospatial working memory, and the central executive.

Long-Term Memory

• Long-term memory (LTM): is the relatively permanent and practically unlimited capacity memory system into which information from short-term memory may pass.

• Explicit memory: also called declarative memory, is our LTM of facts and experiences we consciously know and can verbalize.

• Semantic memory of facts and general knowledge, and episodic memory of personally experienced events.

• Implicit memory: also called non-declarative memory, is our LTM for skills and procedures to do things affected by previous experience without that experience being consciously recalled.

• Procedural memories: are tasks that we perform automatically without thinking, such as tying our shoelaces or swimming.

• Prospective memory: is our memory to perform a planned action or remembering to perform that planned action.

Organization of Memories

• Hierarchies: are systems in which concepts are arranged from more general to more specific classes.

• Concepts: can be simple or complex.

• Prototypes: which are the most typical examples of the concept.

• Semantic networks: are more irregular and distorted systems than strict hierarchies, with multiple links from one concept to others.

• Dr. Steve Kosslyn: showed that we seem to scan a visual image of a picture (mental map) in our mind when asked questions.

• Schemas: are preexisting mental frameworks that start as basic operations and then get more and more complex as we gain additional information.

• Script: is a schema for an event.

• Connectionism: theory states that memory is stored throughout the brain in connections between neurons, many of which work together to process a single memory.

• Artificial intelligence (AI): have designed the neural network or parallel processing model that emphasizes the simultaneous processing of information, which occurs automatically and without our awareness.

• Neural network: computer models are based on neuronlike systems, which are biological rather than artificially contrived computer codes; they can learn, adapt to new situations, and deal with imprecise and incomplete information.

Biology of Long-Term Memory

• Long-term potentiation (or LTP):  involves an increase in the efficiency with which signals are sent across the synapses within neural networks of long-term memories.

• Flashbulb memory: a vivid memory of an emotionally arousing event, is associated with an increase of adrenal hormones triggering release of energy for neural processes and activation of the amygdala and the hippocampus involved in emotional memories.

• The role of the thalamus in memory seems to involve the encoding of sensory memory into short-term memory.

• The hippocampus, frontal and temporal lobes of the cerebral cortex, and other regions of the limbic system are involved in explicit long-term memory.

• Anterograde amnesia: the inability to put new information into explicit memory; no new semantic memories are formed.

• Retrograde amnesia: involves memory loss for a segment of the past, usually around the time of an accident, such as a blow to the head.

• The cerebellum is involved in implicit memory of skills, and studies involving patients with Parkinson’s disease have indicated involvement of basal ganglia in implicit memory too.

Retrieving Memories

• Retrieval: is the process of getting information out of memory storage.

• Multiple-choice questions require recognition, identification of learned items when they are presented.

• Fill-in and essay questions require recall, retrieval of previously learned information.

• Often the information we try to remember has missing pieces, which results in reconstruction, retrieval of memories that can be distorted by adding, dropping, or changing details to fit a schema.

• Hermann Ebbinghaus: experimentally investigated the properties of human memory using lists of meaningless syllables.

  • He drew a learning curve.

  • He drew a forgetting curve that declined rapidly before slowing.

• Savings method: the amount of repetitions required to relearn the list compared to the amount of repetitions it took to learn the list originally.

• Overlearning effect:  Ebbinghaus also found that if he continued to practice a list after memorizing it well, the information was more resistant to forgetting.

• Serial position effect: When we try to retrieve a long list of words, we usually recall the last words and the first words best, forgetting the words in the middle.

• Primacy effect: refers to better recall of the first items, thought to result from greater rehearsal

• Recency effect: refers to better recall of the last items.

• Retrieval cues: can be other words or phrases in a specific hierarchy or semantic network, context, and mood or emotions.

• Priming: is activating specific associations in memory either consciously or unconsciously.

• Distributed practice: spreading out the memorization of information or the learning of skills over several sessions, facilitates remembering.

• Massed practice: cramming the memorization of information or the learning of skills into one session.

• Mnemonic devices: or memory tricks when encoding information, these devices will help us retrieve concepts.

• Method of loci: uses association of words on a list with visualization of places on a familiar path.

• Peg word mnemonic: requires us to first memorize a scheme.

• Context-dependent memory:  Our recall is often better when we try to recall information in the same physical setting in which we encoded it, possibly because along with the information, the environment is part of the memory trace

• Mood congruence: aids retrieval.

• State-dependent: things we learn in one internal state are more easily recalled when in the same state again.

• Forgetting:  may result from failure to encode information, decay of stored memories, or an inability to access information from LTM.

• Relearning: is a measure of retention of memory that assesses the time saved compared to learning the first time when learning information again.

Cues and Interference

• Tip-of-the-tongue phenomenon:  Sometimes we know that we know something but can’t pull it out of memory.

• Interference:  Learning some items may prevent retrieving others, especially when the items are similar.

• Proactive interference: occurs when something we learned earlier disrupts recall of something we experience later.

• Retroactive interference: is the disruptive effect of new learning on the recall of old information.

• Sigmund Freud: believed that repression (unconscious forgetting) of painful memories occurs as a defense mechanism to protect our self-concepts and minimize anxiety.

• Misinformation effect: occurs when we incorporate misleading information into our memory of an event.

• Misattribution error:  Forgetting what really happened, or distortion of information at retrieval, can result when we confuse the source of information—putting words in someone else’s mouth—or remember something we see in the movies or on the Internet as actually having happened.

• Language: is a flexible system of spoken, written, or signed symbols that enables us to communicate our thoughts and feelings.

Building Blocks: Phonemes and Morphemes

• Language is made up of basic sound units called phonemes.

• Morphemes: are the smallest meaningful units of speech, such as simple words, prefixes, and suffixes.

Combination Rules

• Each language has a system of rules that determines how sounds and words can be combined and used to communicate meaning, called grammar.

• The set of rules that regulate the order in which words can be combined into grammatically sensible sentences in a language is called syntax.

• The set of rules that enables us to derive meaning from morphemes, words, and sentences is semantics.

Language Acquisition Stages

• Babbling is the production of phonemes, not limited to the phonemes to which the baby is exposed.

• Holophrase: one word—to convey meaning.

• Telegraphic speech:  they begin to put together two-word sentences.

• Overgeneralization: or overregularization in which children apply grammatical rules without making appropriate exceptions.

Theories of Language Acquisition

• Noam Chomsky says that our brains are prewired for a universal grammar of nouns, verbs, subjects, objects, negations, and questions.

• He compares our language acquisition capacity to a “language acquisition device,” in which grammar switches are turned on as children are exposed to their language.

Thinking

• Linguist Benjamin Whorf proposed a radical hypothesis that our language guides and determines our thinking.

  • He thought that different languages cause people to view the world quite differently.

• Linguistic relativity hypothesis: has largely been discredited by empirical research.

• Metacognition: thinking about how you think

Problem Solving

• Algorithm: is a problem-solving strategy that involves a slow, step-by-step procedure that guarantees a solution to many types of problems.

• Insight: is a sudden and often novel realization of the solution to a problem.

• Trial-and-error approach: This approach involves trying possible solutions and discarding those that do not work.

• Inductive reasoning: involves reasoning from the specific to the general, forming concepts about all members of a category based on some members, which is often correct but may be wrong if the members we have chosen do not fairly represent all of the members.

• Deductive reasoning: involves reasoning from the general to the specific.

Obstacles to Problem Solving

• Fixation: is an inability to look at a problem from a fresh perspective, using a prior strategy that may not lead to success.

• Functional fixedness: a failure to use an object in an unusual way.

• Amos Tversky and Nobel Prize winner Daniel Kahneman studied how and why people make illogical choices.

• Availability heuristic: estimating the probability of certain events in terms of how readily they come to mind.

• Representative heuristic: a mental shortcut by which a new situation is judged by how well it matches a stereotypical model or a particular prototype.

• Framing: refers to the way a problem is posed.

• Anchoring effect: is this tendency to be influenced by a suggested reference point, pulling our response toward that point.

Biases

• Confirmation bias: is a tendency to search for and use information that supports our preconceptions and ignore information that refutes our ideas.

• Belief perseverance: is a tendency to hold onto a belief after the basis for the belief is discredited.

• Belief bias: the tendency for our preexisting beliefs to distort logical reasoning, making illogical conclusions seem valid or logical conclusions seem invalid.

• Hindsight bias: is a tendency to falsely report, after the event, that we correctly predicted the outcome of the event.

• Overconfidence bias: is a tendency to underestimate the extent to which our judgments are erroneous.

Creativity

• Creativity: is the ability to think about a problem or idea in new and unusual ways, to come up with unconventional solutions.

• Convergent thinkers: use problem-solving strategies directed toward one correct solution to a problem

• Divergent thinkers: produce many answers to the same question, characteristic of creativity.

• Brainstorm: generating lots of ideas without evaluating them.

Standardization and Norms

• Psychometricians: are involved in test development in order to measure some construct or behavior that distinguishes people.

• Constructs: are ideas that help summarize a group of related phenomena or objects; they are hypothetical abstractions related to behavior and defined by groups of objects or events.

• Standardization: is a two-part test development procedure that first establishes test norms from the test results of the large representative sample that initially took the test and then ensures that the test is both administered and scored uniformly for all test takers.

• Norms: are scores established from the test results of the representative sample, which are then used as a standard for assessing the performances of subsequent test takers; more simply, norms are standards used to compare scores of test takers.

Reliability and Validity

• If a test is reliable, we should obtain the same score no matter where, when, or how many times we take it (if other variables remain the same).

  • Several methods are used to determine if a test is reliable.

• Test-retest method: the same exam is administered to the same group on two different occasions, and the scores compared.

• Split-half method: the score on one half of the test questions is correlated with the score on the other half of the questions to see if they are consistent.

• Alternate form method or equivalent form method: two different versions of a test on the same material are given to the same test takers, and the scores are correlated.

• Interrater reliability: the extent to which two or more scorers evaluate the responses in the same way.

• Validity: is the extent to which an instrument accurately measures or predicts what it is supposed to measure or predict.

Performance, Observational, and Self-Report Tests

• Performance test: the test taker knows what he or she should do in response to questions or tasks on the test, and it is assumed that the test taker will do the best he or she can to succeed.

  • Performance tests include the SATs, AP tests, Wechsler intelligence tests, Stanford–Binet intelligence tests, and most classroom tests, including finals, as well as computer tests and road tests for a driver’s license.

• Observational tests: differ from performance tests in that the person being tested does not have a single, well-defined task to perform but rather is assessed on typical behavior or performance in a specific context.

• Speed tests: generally include a large number of relatively easy items administered with strict time limits under which most test takers find it impossible to answer all questions.

Ability, Interest, and Personality Tests

• General mental ability is particularly important in scholastic performance and in performing cognitively demanding tasks.

• Interests influence a person’s reactions to and satisfaction with his or her situation.

• Personality involves consistency in behavior over a wide range of situations.

• Aptitude tests are designed to predict a person’s future performance or to assess the person’s capacity to learn, and achievement tests are designed to assess what a person has already learned.

Ethics and Standards in Testing

• Tests: are developed and used ethically to avoid abuse.

• Numerous professional organizations, including the American Psychological Association, have published technical and professional standards for the construction, evaluation, interpretation, and application of psychological tests to promote the client's welfare and best interests, protect assessment results from misuse, respect the client's right to know the results, and protect test takers' dignity.

• Personnel testing: requires informed consent and confidentiality from psychologists.

• Professionals should use tests as intended.

Intelligence and Intelligence Testing

• Reification: occurs when a construct is treated as though it were a concrete, tangible object.

• Intelligence test developer David Wechsler said, “Intelligence, operationally defined, is the aggregate or global capacity of the individual to act purposefully, to think rationally, and to deal effectively with his environment.”

Francis Galton’s Measurement of Psychophysical Performance

• Francis Galton: who measured psychomotor tasks to gauge intelligence, reasoning that people with excellent physical abilities are better adapted for survival and thus highly intelligent.

• James McKeen Cattell: brought Galton’s studies to the United States, measuring strength, reaction time, sensitivity to pain, and weight discrimination, using the term mental test.

• French psychologist Alfred Binet was hired by the French government to identify children who would not benefit from a traditional school setting and those who would benefit from special education.

  • He collaborated with Theodore Simon to create the Binet–Simon scale, which he meant to be used only for class placement.

Alfred Binet’s Measurement of Judgment

• Binet believed that as we age, our knowledge of the world becomes more sophisticated, so most 6-year-olds answer questions differently than 8-year-olds.

• Children were given a mental age or level based on their test responses.

• When a 6-year-old and an 8-year-old have mental ages 2 years below their chronological ages, it can be misleading.

• The younger child would lag behind peers more.

• German psychologist William Stern suggested determining a child's intelligence by comparing mental age (MA) to chronological age (CA).

Mental Age and the Intelligence Quotient

• Lewis Terman: developed the Stanford–Binet Intelligence Scale reporting results as an IQ, intelligence quotient, which is the child’s mental age divided by his or her chronological age, multiplied by 100; or MA/CA × 100.

The Wechsler Intelligence Scales

• David Wechsler: developed another set of age-based intelligence tests: the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) for preschool children, the Wechsler Intelligence Scale for Children (WISC) for ages 6 to 16, and the Wechsler Adult Intelligence Scale (WAIS ) for older adolescents and adults.

• Intellectual disability:  Test takers who fall two deviations below the mean have a score of 70

Intellectual Disability

• Over the past two decades, the term mental retardation has been replaced by intellectual disability (intellectual developmental disorder).

• To be considered intellectually disabled, an individual must earn a score at or below 70 on an IQ test and also show difficulty adapting in everyday life.

• Adaptive behavior: is expressed in conceptual skills, social skills, and practical skills.

• Severity: is determined by adaptive functioning rather than IQ score.

Kinds of Intelligence

• A contemporary of Alfred Binet, Charles Spearman, tested a large number of people on a number of different types of mental tasks.

• Factor analysis: a statistical procedure that identifies closely related clusters of factors among groups of items by determining which variables have a high degree of correlation.

• Louis Thurstone disagreed with Spearman’s concept of g.

• John Horn and Raymond Cattell determined that Spearman’s g should be divided into two factors of intelligences: fluid intelligence, those cognitive abilities requiring speed or rapid learning that tend to diminish with adult aging, and crystallized intelligence, learned knowledge and skills such as vocabulary that tend to increase with age.

Multiple Intelligences

• Howard Gardner: is one of the many critics of the g or single factor intelligence theory.

  • He has proposed a theory of multiple intelligences.

  • Three of his intelligences are measured on traditional intelligence tests: logical-mathematical, verbal-linguistic, and spatial.

  • Five of his intelligences are not usually tested on standardized tests: musical, bodily-kinesthetic, naturalistic, intrapersonal, and interpersonal.

  • Gardner has also introduced the possibility of a ninth intelligence—existential—which would be seen in those who ask questions about our existence, life, death, and how we got here.

• Savants: individuals otherwise considered mentally retarded, have a specific exceptional skill, typically in calculating, music, or art.

• Peter Salovey and John Mayer labeled the ability to perceive, express, understand, and regulate emotions as emotional intelligence.

• Triarchic theory of intelligence: analytic, creative, and practical.

• Analytical thinking: is what is tested by traditional IQ test and what we are asked to do in school—compare, contrast, analyze, and figure out cause and effect relationships.

• Creative intelligence: is evidenced by adaptive reactions to novel situations, showing insight, and being able to see more than one way to solve a problem.

• Practical intelligence: is what some people consider “street smarts.”

Creativity

• Creativity: the ability to generate ideas and solutions that are original, novel, and useful, is not usually measured by intelligence tests.

• According to the threshold theory, a certain level of intelligence is necessary, but not sufficient for creative work.

Heredity/Environment and Intelligence

• Down syndrome: is primarily hereditary, whereas intellectual disability resulting from prenatal exposure to alcohol

• Fetal alcohol syndrome: is primarily environmental.

• Phenylketonuria (PKU): results from the interaction of nature and nurture

Environmental Influences on Intelligence

• Flynn effect: cannot be attributed to a change in the human gene pool because that would take hundreds of years.

  • Theorists attribute the Flynn effect to a number of environmental factors, including better nutrition, better health care, advances in technology, smaller families, better parenting, and increased access to educational opportunities.

• Heritability: is the proportion of variation among individuals in a population that results from genetic causes.

• According to the reaction range model, genetic makeup determines the upper limit for an individual’s IQ, which can be attained in an ideal environment, and the lower limit, which would result in an impoverished environment.

Human Diversity

• Racial differences in IQ scores show African Americans, Native Americans, and Hispanic Americans typically scoring 10 to 15 points below the mean for white children.

• When comparing groups of people on any construct, such as intelligence, it is important to keep in mind the concept of within-group differences and between-group differences.

• The range of scores within a particular group, such as Hispanic Americans, is much greater than the difference between the mean scores of two different groups, such as Hispanic Americans and Asian Americans.

Stereotype Threat

• Stereotypes: are overgeneralized beliefs about the characteristics of members of a particular group, schema that are used to quickly judge others.

• Stereotype threat: anxiety that influences members of a group concerned that their performance on a test will confirm a negative stereotype, has been evidenced in studies by Steele, Joshua Aronson, and many others.