The phenomenon of memory
Memory is the persistence of learning over time, through the storage and retrieval of information. Flashbulb memories, which are attached to emotionally significant moments or events, differ from most other memories in their striking clarity. The Atkinson-Shriffin classic three-stage model of memory suggests that we (1) register fleeting sensory memories, some of which are (2) processed into on-screen short-term memories, a tiny fraction of which are (3) encoded for long-term memory and, possibly later retrieval. In pointing out the limits of this model, contemporary memory researchers note that we register some information automatically, bypassing the first two stages. And they prefer the term working memory (rather than short-term memory) because it emphasizes a more active role in this second processing stage, where we rehearse and manipulate information, associating new stimuli with older stored memories. The working meory model includes visual-spatial and auditory subsystem, coordinated by a central executive processor that focuses attention where needed.
Encoding: Getting information In
We unconsciously and automatically encode incidental information, such as space, time and frequency. We also register well-learned information, such as words in out native language, by this form of processing.
Automatic processing happens unconsciously, as we absorb information (space, time, frequency, well-learned material) in our environment. Effortful processing (of meaning, imagery, organization) requires conscious attention and deliberate effort (rehearsal). The next-in-line effect is our tendency to forget (through failure in encoding) what the person ahead of us in line has said because we are focusing on what we will say in our upcoming turn. The spacing effect is our tendency to retain information more easily if we practice it in one long session (cramming). The serial position effect is our tendency to recall the first and last items in a long list (such as grocery list) more easily than we recall the inverting items.
Visual encoding (of picture images) and acoustic encoding (of sounds, especially of words) are shallower forms of processing than is semantic encoding (of meaning). We process verbal information best when we encode it semantically, especially if we apply the self-reference effect, making information “relevant to me”.
Encoding imagery aids effortful processing because vivid images are very memorable. We tend to remember concrete nouns better than abstract nouns because, for example, we can associate both an image and a meaning with gorilla, but only a meaning with process. Many Mnemonic devices (memory strategies or aids) rely on imagery. Other trap items in memory by combining visual encoding (imagining a series of vivid images) and acoustic encoding (a memorable rhyme).
We remember organized information better than we do random data, and chunking and hierarchies are two ways to organize information. In chunking, we cluster information into familiar, manageable units, such as words into sentences. In hierarchies, we process information by dividing it into logical levels, beginnings with the most general and moving to the most specific.
Storage: Retaining Information
As information enters the memory system through our senses, we register and store visual images via iconic memory, in which picture images last no more than a few tenths of a second. We register and store sounds via echoic memory, where echoes of auditory stimuli may linger as long as 3 or 4 seconds.
At any given time, we can focus on and process only about seven items of information (either new or retrieval from our memory store). Without rehearsal, information disappears within seconds from short-term memory and is forgotten.
Our capacity for storing information permanently in long-term memory is essentially unlimited.
Contemporary researchers are focusing on memory-related changes within and between single neurons. As experience strengthens the pathways between neurons, synapses transmit signal more efficiently. In a process known as long-term potential (LTP), sending neurons in these pathways release neurotransmitters more quickly, and receiving neurons may develop additional receptors, increasing their ability to detect the incoming neurotransmitters. LTP appears to be the neural basis for learning and memory.
By enabling the production of extra glucose (which fuels brain activity), stress hormones alert the brain to important events. The amygdala, an emotion-processing structure in the brain's limbic system, arouses brain areas that process emotion. These emotion-triggered hormonal changes may produce indelible memories.
We are often not aware of our implicit (procedural) memories- Our memories of our own skills and operantly and classically conditioned responses. These memories are processed in part conditioned responses. The memories are processed in part by the cerebellum, near the brainstem. We consciously recall our explicit (declarative) memories – our general knowledge, specific factors, and personally experienced events. Explicit memories are processed in various subregions of the hippocampus ( a neural center in the limbic system) and sent for storage in other areas in the brain. The implicit and explicit memory system are independent. Damage to the hippocampus may destroy the ability to consciously recall memories, without destroying skills or classically conditioned responses.
Retrieval: Getting Information Out
Recall is the ability to retrieve information not in conscious awareness; a fill-in-the-blank question tests recall. Recognition is the ability to identify items previously learned; a multiple choice question tests recognition. Relearning is the ability to master previously stored information more quickly than you originally learned it.
Retrieval cues are bits of related information we encode while processing a target piece of information. These bits are linked in some way to the context of the target, and they become a part of a web of stored associations. When one of these associated bits catches out attention into our conscious awareness. This process of activating associations (often unconsciously) is priming.
The context in which we originally experienced an event or encoded a thought can flood our memories with retrieval cues, leading us to the target memory. If we are in a different context that is very similar to the original one, we may experience deja vu as many of these cues return and trick us into unconsciously retrieving the target memory.
Specific states or emotions can prime us to recall events associated with those stated or emotions. While in a good mood, we tend to retrieve memories consisted – or congruent – with that happy state. When depressed we more easily recall negative memories. Moods also prime us to interpret others' behavior in ways consistent with our emotions.
Forgetting
Without an ability to forget, we would be overwhelmed by out-of-date and irrelevant information. Our memory can fail us through forgetting (absent-mindedness, transience, and blocking), through distortion (misattribution, suggestibility, and bias), and through intrusion (persistence if unwanted memories).
What we encode (whether automatically or through Effortless processing) is only a very limited portion of the sensory stimuli around us. And as we age, our encoding grows slower and less efficient. Without encoding, information does not enter out long-term memory store and cannot be retrieved.
Encoded memories may fade after storage. From his research on learning and retention, Ebbinghaus determined that the course of forgetting is initially rapid, then levels off with time, this principle became known as the forgetting curve.
One way retrieval failure happens is when old and new information compete for retrieval. In proactive interference, something we learned in the past ( a friend's old phone number) interferences with out ability to recall something we have recently learned ( the friend's new number). In retroactive interference, something we have recently learned ( vocabulary in this semester's Spanish course) interferes with something we learned in the past (vocabulary in last year's French course).
Freud believed that we banish from conscious thought anxiety-arousing thought, feelings, and memories – a concept he called repression. In his view, this motivated forgetting submerges memories but leaves them available for later retrieval under the right condition. Memory researchers tend to believe that repression rarely occurs.
Memory construction
Memories are not stored or retrieved as exact copies of our experiences, rather, we construct our memories, using both stored and new information. If children or adults are subtly exposed to misinformation after an event, or if they repeatedly imagine and rehearse an event that never occurred, they may incorporate the misleading details into their memory of what actually happened. Memory is thus best understood not only as a cognitive and a biological phenomenon, but also as a social-cultural phenomenon.
When we process memories, we encode and store various aspects of them in different locations in the brain. In resembling a memory during retrieval, we may successfully retrieve something we have heard, read, or imagined, but attribute it to the wrong source. Source amnesia is one of two main components of false memories. (the other is the misinformation effect).
False memories feel like true memories and are equally durable, so neither the sincerity nor the longevity of a memory signifies it is real. True memories contain more details than imagined ones, which tend to be gist of an event- the meaning and feelings associated with it.
A supporting argument: Even very young children can accumulatively recall events (and the people involved) if a neutral person talks with them in words they can understand, asks non leading questions, and uses the cognitive interview technique. A rejecting argument: Preschoolers are more suggestible than older children or adults, and they can be induced, through suggestive questions, to report false events.
Psychologists motivated to protect abuse children and wrongly accused adults tend to agree on seven points: (1) Innocent people have been falsely convicted of abuse that never happened, and true abusers have used the controversy over recovered memories to avoid punishment. (2) incest and abuse happen, and they leave lasting scars. (3) forgetting isolated past events, either good or bad is an everyday occurrence for all of us. (4) recovering good or bad memories, triggered by some memory cue, is commonplace, but memory researchers question whether we forcibly repress memories in Freud's sense, to avoid anxiety or pain. (5) memories obtained under the influence of hypnosis or drugs are unreliable. (6) infantile amnesia – the inability to recall memories from the first 3 years of life – makes recovery of very early childhood memories unlikely. (7) both real and false memories cause suffering and can lead to stress disorders.
Improving memory
The psychology of memory suggests concrete strategies for improved memory. These include scheduling spaced study times; actively rehearsing information to be learned; aiding encoding by making well-organized, vivid, and personally meaningful associations; using mnemonic techniques; returning to contexts and moods that are rich with associations; recording memories before misinformation can corrupt them; minimizing interference; and self-testing to rehearse information and find gaps in your memory.
Thinking and language
Thinking
Cognition is a term covering all the mental activities associated with thinking, knowing, remembering, and communication.
We use concepts to simplify and order the world around us. We divide clusters of objects, events, ideas, or people into categories based on their similarities. In creating hierarchies, we subdivide these categories into smaller and more detailed units. We form other concepts, such as triangles, by definition (three-sides objects). But we form most concepts around prototypes, or best examples of a category. Matching objects and ideas against prototypes is an efficient way of making snap judgments about what belongs in a specific category.
An algorithm is a time-consuming but through set of rules or procedures (such as a recipe for cookies, or a step-by-step description for evacuating a building during a fire) that guarantees a solution to a problem. A heuristic is a simpler thinking strategy (such as running for an exit if you smell heavy smoke) that may allow is to incorrect solutions. Insight differs form both because it is not a strategy-based solution, but rather an Aha! reaction-a sudden flash of inspiration that solves a problem.
The confirmation bias predispose us to verify rather than challenge our hypnosis. Fixation, such as mental set and functional fixedness, may leave us doggedly pursuing one line of reasoning and prevent us from taking the fresh perspective that would let us solve the problem.
The representativeness heuristic leads is to judge the likelihood of things in term of how they represent our prototype for a group of items. The availability heuristic leads us to judge the likelihood of thing based on how vivid they are or how readily they come to mind. Either of these two thinking shortcuts can cause us to ignore important information or to underestimate the chances of something happening.
The main drawback of overconfidence is that our tendencies to seek confirmation of our hypotheses and to use quick and easy heuristic can blind us to our vulnerable to error – a fault that can be tragic if we are in a position of responsibility. But on a personal level, overconfident people tend to live happier lives, make difficult decisions more easily,and seem more credible.
An issue can be presented (or framed) in different but equally logical ways, but the subtle wording can nudge us in the direction the questioner wants us to take. (consider, for example, “Do you think people should be free to smoke in public places? “ versus “Do you think smokers should have the right to expose the lungs of nonsmokers to second-hand smoke?”)
We tend to judge conclusions that agree with our beliefs as more logical than those that do not match our beliefs. This belief bias can lead us to accept invalid conclusions and reject valid ones.
Belief perseverance is clinging to our ides because the explanation we once accepted as valid lingers in our mind even after it has been discredited. The best remedy for this form of bias is making the effort to consider evidence supporting the opposite position.
Although it sometimes leads us astray, human intuition can be remarkably efficient and adaptive, giving us instant help when we need it. As we gain expertise in a field, for example, we grow adept at making quick, shrewd judgments. Smart thinkers will welcome their intuitions but check them against available evidence, hoping to avoid overconfidence and biased and illogical thinking.
Language
All languages have the same basic structural units. Phonemes are the basic units of sound and language. Morphemes are the elementary units of meaning; some (such as I) are words, but most are elements such as prefixes (anti-) or suffixes (-ing). Grammar is the system of rules (mental rules, not those taught in English classes) that enable us to communicate and understand others. Semantics, which is part of grammar, is set of rules for deriving meaning in a given language. Syntax, also a part of grammar, is the set of rules for ordering words into sentences.
At about 4 months of age, infants babble, making a wide range of sounds found in language located all over the world. By about 10 months, their babbling contains only the sounds found in their household language. Around 12 months of age, babies speak in single words. This one-word stage evolves into two-word (telegraphic) utterances before their second birthday. Shortly after that, children begin speaking in full sentences. The timing of these stages varies a little from one child to another, but all children follow this sequence.
Behaviorists B.F. Skinner (representing the nurture side of the language-developing debate) proposed that we learn language by the familiar principles of association (of sights of things with sounds of words), imitating (of words and syntax modeled by others), and reinforcement (with smiles and hugs after saying something right). Challenge this claim, linguist Noam Chomsky (representing the nature position) argues that were born with language acquisition device that biologically prepares is to learn language. He cites as evidence the species-wide presence of language and its underlying universal grammar; children's amazing rate of acquiring vocabulary; and the uniform sequence of the stage of language development. Statistical learning is the ability to detect speech patterns (such as syllable breaks). Childhood is a critical period for learning spoken and signed language: Children who do not learn language during this early period lose their ability to fully master language.
Thinking and language
Although the linguistic determinism hypothesis suggest that language determines thought, it is more accurate to say that language influences thought. Words convey ideas, and research on people who are bilingual demonstrates that different languages embody different ways of thinking. Studies of the effects of the generic pronoun he show that subtle prejudices can be conveyed by the words we choose to express our everyday thoughts. Some evidence indicates that vocabulary enrichment, particularly immersion in bilingual education, can enhance thinking.
We often think in images when we use procedural memory - our unconscious memory system for motor and cognitive skills and conditioned association. Researchers have found that thinking in images is especially useful for mentally practicing upcoming events and can actually increase our skills.
Animal thinking and language
Both humans and the great apes form concepts, display insight, use and create tools, transmit cultural innovations, and have a theory of mind (including the capacity for reasoning, self-recognition, empathy, imitation, and understanding another's mind).
Bees dance to communicate the direction and distance of food, parrots sort items by number, and dogs comprehend and respond to complicated human commands. Several species of apes have learned to communicate with humans by signing or by pushing buttons wired to a computer. These apes have developed vocabularies of hundreds of words, communicated by striking these words together,and have taught their skills to younger animals, who – like humans tend to acquire the skills most easily and thoroughly taught them at a very young age. Netherless, research reveals an important difference between apes' and humans' facilities with language. Only humans can master the verbal or signed expression of complex rules of syntax.
Intelligence
What is intelligence?
Intelligence is a socially constructed concept that differs from culture to culture. The two big controversies in current research on intelligence are (1) whether it is one overall ability or many, and (2) whether neuroscientists can locate and measure intelligence within the brain. To reify intelligence is to treat it as though it were a real object, not an abstract concept. Most psychologists now define intelligence as the ability to learn from experience to solve problems, and adapt to new situations.
Arguments for considering intelligence as a general mental ability underlying all specific mental ability underlying all specific mental abilities are based in part on factor analysis. This statistical procedure has been used to show that mental abilities tend to form clusters, and that people tend to show about the same level of competence in all abilities in the cluster. In the mid-twenties century, Charles Spearman ( a developer of factor analysis) names this common level of intelligence the g factor. Some psychologists today agree with Spearman's idea that we have a common level of intelligence that can predict our abilities in all other academic areas.
Howard Gardner dispute of one general intelligence. He proposes eight independent intelligences: Linguistic (word smart), Logical-mathematical (number smarts), musical (music smarts), spatial (space smarts), bodily-kinesthetic (body smarts), intrapersonal (self smart), interpersonal (people smarts), and natural (nature smarts). Robert Sternberg's triarchic theory proposes only three intelligences: analytical (academies problem solving), creative, and practical intelligences.
The four components of emotional intelligence are the ability to perceive emotions (to recognize them in faces, music, and stories), to understand emotions (to predict them and how they change and blend), to manage emotions ( to know how to express them in varied situations) and to use emotions. Critics of the ideas of emotional intelligence question whether we stretch the ideas of intelligence too far when we apply it to emotions.
Creativity is the ability to produce novel and valuable ideas. It correlates somewhat with intelligence, but beyond a score of 120, that correlation dwindles. It also correlates with expertise, imaginative thinking skills, a venturesome personality, intrinsic motivation, and the support offered by a creative environment. Different brain areas are active when we engage in convergent thinking (the type required for multiple imaginative solutions).
Recent studies indicate come correlation (about +.40) between brain size (adjusted for body size) and intelligence score. The brain's tendency to decrease in size during late adulthood, as nonverbal; intelligence test score also decrease, supports this idea to some extent. And autopsies of some highly educated people revealed above-average volumes of synapses and gray matter. But the direction of the relationship is not clear. Larger brain size may enable greater intelligence; greater intelligence may lead to experiences that exercise the brain and build more connections, thus increasing its size; or some third factor may be at work.
Studies of brain functioning show that people who score high on intelligence tests tend also to retrieve information from memory more quickly, and to perceive stimuli faster than others. These differences are reflected in neurological studies that show faster brain response times.
Assessing Intelligence
Psychologists define intelligence test as a method for assessing an individuals mental aptitudes and comparing them with those of others, using numerical scores. More than a century ago in France, Alfred Binet and his collaborator Theodor Simon started the modern intelligence-testing movement by developing questions that helped predict children's future progress in the Paris school system. Lewis Terman of Standford university revised Binet's works for use in the United States. Terman believed his Standford-Binet could help guide people toward appropriate opportunities, but more than Binet, he believed intelligence is inherited. During the early twentieth century, intelligence tests were, regrettably, sometimes used to “document” assumptions about the innate inferiority of certain ethnic and immigrant groups. Intelligence test scores have been expressed as an intelligence quotient (IQ), established by dividing mental age by chronological age times 100.
Aptitude tests are designed to predict what you can learn. Achievement tests are designed to assess what you have learned. The WAIS (Wechsler Adult Intelligence Scale), and aptitude test, is the most widely used intelligence tests for adult. Two similar Wechsler scales are designed to test intelligence in preschool and older children. The SAT scores and their score on a test of general intelligence correlated at a very high level: +.82.
Standardizing a test is the process of administering the test to a representative sample of future test-takers in order to establish a basis for meaningful comparisons of scores. The distribution of many physical and psychological attributes forms a normal curve (also known as a bell-shaped-curve) – a roughly symmetrical shape in which most scores cluster around an average, and increasingly fewer are distributed at the extremes. Intelligence test score has risen 27 points – a phenomenon known as the Flynn effect.
A test is reliable when it yields consistent results. To establish reliability, researchers compare the consistency of test-takers' scores on two halves of the test, alternate forms of the test, or retests on the same test. A test can be reliable but not valid.
A valid test measures or predicts what it is supposed to. Content validity is the extent to which a test samples the pertinent behavior ( as a driving test measure driving ability). Predictive validity is the extent to which the test predicts a behavior it is designed to predict (aptitude tests have predictive ability if they can predict future achievements).
The dynamics of intelligence
The stability of intelligence test scores increase with age. By age 4, scores fluctuate somewhat but begin to predict adolescent and adult scores. At about age 7, scores become fairly stable and consistent.
If an intelligence test is valid, the two groups of people falling at the extremes of the normal curve should be significantly different, and they are. Those with scores below 70, the cut-off mark for the diagnosis of mental retardation, vary in their abilities form near-normal, to (at the very lowest scoring levels) requiring constant aid and supervision. Down syndrome is a form of retardation with a physical cause – an extra copy of chromosome 21. High scoring people, contrary to popular myths, tend to be healthy, well adjusted, and unusually successful academically. Schools sometimes “track” such children, separating them from those with lower scores. Such programs can become self-fulfilling prophecies as children live up to – or down to – other's perceptions of their ability.
Genetic and environmental influences on intelligence
Studies of twins, family members, and adopted children together support the idea that there is a significant genetic contribution to intelligence scores. The most genetically similar people have the most similar scores, ranging from about +.85 for identical twins raised together, to about +.33 for unrelated individuals raised together. No “genius gene” has been discovered yet but the search is under way. Heritability of intelligence refers to the extent to which variation in intelligence test scores in a group of people being studied is attributable to genetic factors. Heritability never applies to an individual's intelligence, but only to differences among people.
Studies of twins, family member, and adopted children also provide evidence of environmental influence. The intelligence test scores of fraternal twins raised together are more similar than those of other siblings, and the scores of identical twins raised apart are less similar (though still very highly correlated) than the scores of identical twins raised together. Other studies, of children reared in extremely impoverished, enriched, or culturally different environments, indicate that life experiences significantly influence intelligence tests performance.
As a group, white Americans tend to have an average intelligence test score about 8 to 15 points higher than their Hispanic or African-American counterparts. This gap has dropped recently among children. The evidence suggests that environmental differences are largely responsible for these group differences. Six points were considered in this chapter. (1) The races are remarkably alike genetically. (2) Race is a socially, not biologically, defined category. (3) Asian students outperform North American students on math achievement and aptitude test. (4) Intelligence test performance of todays, better-fed, better-educated, and more test-prepared population exceeds that of the 1930s population, by the same margin that the score of the average white today exceeds that of the average black. (5) white and black infants tend to score equally well on tests predicting future intelligence. (6) in different eras, different ethnic groups have experienced periods of remarkable achievement.
This chapter considered seven ways that males and females differ in their abilities. (1) girls are better spellers. (2) girls are more verbally fluent and can remember more words. (3) girls are better at locating objects. (4) girls are more sensitive to touch, taste, and color. (5) boys are outnumber girls in counts of underachievement.
(6) boys outperform girls at math problems solving, though girls outperform boys in math computations.
(7)Women detect emotions more easily than men do.
Aptitude tests aim to predict how well a test-taker will perform in a given situation. So they are necessarily biased in the sense that they are sensitive to performance differences caused by cultural experience. But bias can also mean what psychologists commonly mean by the term – that a biased test predicts less accurately for one group than for another. In this sense of the term, most experts do not consider the major aptitude tests to be significantly biased. Stereotype threat is a self-confirming concern that one will be evaluated based on a negative stereotype. This phenomenon appears in some instances in intelligence testing among African-Americans and among women of all colors.
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