174 Fun Facts About Psychology

In the Milgram experiment, participants believed they were administering what to a 'learner'?

Electric shocks were faked and the 'learner' was an actor; psychiatrists polled beforehand predicted about one person in a thousand would reach the 450-volt maximum, yet 26 of 40 did.

Many soldiers diagnosed with 'shell shock' in World War I would today be said to have which disorder?

Post-traumatic stress disorder became an official diagnosis only in 1980; doctors first blamed 'shell shock' on blasts shaking the brain, until the same symptoms appeared in men who had been nowhere near an exploding shell.

Which 1971 Philip Zimbardo experiment was stopped after only six days because of how its volunteers behaved?

Stanford Prison was planned to run two weeks; Zimbardo halted it after psychologist Christina Maslach, brought in to interview participants, confronted him over how the student guards were treating prisoners.

Which of the following is one of the 'Big Five' personality traits?

Conscientiousness joins openness, extraversion, agreeableness and neuroticism in the OCEAN mnemonic; people who score high on it tend to earn better grades and stronger job-performance ratings.

The concept of classical conditioning is most famously associated with which researcher?

Ivan Pavlov's dogs learned to salivate at a neutral signal paired with food; his 1904 Nobel Prize was actually for work on the physiology of digestion.

Which school of psychology rejects introspection and studies only what can be observed and measured from outside?

Behaviorism was set out in a 1913 paper and shaped American psychology until the second half of the century, when the 'cognitive revolution' brought the study of the mind back in.

What did Carl Jung call universal patterns such as the Hero and the Trickster?

Archetypes surface in myths and dreams across cultures, Jung argued; Joseph Campbell's 'hero's journey' charts one such pattern, and George Lucas used Campbell's writings as a direct reference for Star Wars.

Which American psychologist proposed a hierarchy of needs, with physiological needs met before higher psychological ones?

Abraham Maslow set out the theory in a 1943 paper but never drew it as a pyramid; the famous triangle first appeared in 1960, in a business-journal article by a consulting psychologist.

Which brain structure is primarily responsible for processing emotions, especially fear?

The amygdala is an almond-shaped cluster deep in each temporal lobe; a woman known as S.M., whose amygdalae no longer work, showed no fear of snakes, spiders or a haunted house.

Which cognitive bias is the tendency to favour and recall information that supports what one already believes?

Confirmation bias showed up in a Stanford study of the death penalty: supporters and opponents read the same two studies, and each side found the one backing its own view the more convincing.

Which psychologist's theory of cognitive development includes the sensorimotor and formal operational stages?

Jean Piaget built much of the theory by watching and questioning his own three children, then analysing the mistakes they made on simple problems he set them.

The Rorschach inkblot test is an example of which type of psychological assessment?

Projective tests assume people read their own hidden feelings into ambiguous images; Hermann Rorschach, nicknamed 'Inkblot' at school, died at 37, a year after publishing his test.

Who conducted the 'Little Albert' experiment on conditioned emotional responses?

John B. Watson and Rosalie Rayner struck a steel bar behind the infant whenever he reached for a white rat, at Johns Hopkins, until the sight of the rat alone made him cry.

Which organisation publishes the DSM-5, America's principal authority for mental-disorder diagnoses?

The American Psychiatric Association first published the manual in 1952; in December 1973 its trustees voted to remove homosexuality from the list of disorders, and members confirmed the decision the next year.

What phenomenon makes a person less likely to help a victim when others are present?

The bystander effect, studied by Darley and Latané in 1968, is usually explained by diffusion of responsibility: everyone assumes someone else will step in, so nobody does.

Which of these is a Gestalt principle of how we organize what we perceive?

Figure-Ground: the eye tends to treat small, convex, symmetric or enclosed regions as objects and the rest as backdrop; when the cues balance, the picture keeps flipping.

Which psychologist won a Nobel for split-brain research on the hemispheres' specialised functions?

Roger Sperry shared the 1981 Nobel Prize in Physiology or Medicine with Hubel and Wiesel; his split-brain patients' two hemispheres could act almost as separate minds.

What is a persistent, irrational fear of a specific object or situation called?

A phobia can begin with a single frightening experience and can be unlearned much the same way: therapy exposes the person to the feared thing in small steps until the alarm fades.

What Festinger theory describes the discomfort of holding contradictory beliefs?

Cognitive Dissonance grew partly from When Prophecy Fails, Festinger's study of a UFO cult whose members, he reported, began seeking converts after the predicted catastrophe failed to arrive.

Who developed social cognitive theory, which emphasizes observational learning and modeling?

Albert Bandura first called it social learning theory; he renamed it in 1986 to stress that people think about what they watch others do rather than simply copy it.

Which psychologist's line-judgment studies showed how individuals yield to a unanimous but wrong majority?

Solomon Asch's task was so easy that near-100% accuracy was expected, until a planted majority gave the wrong answer and real participants went along.

In the famous pyramid-shaped hierarchy of needs, which need sits at the very top?

Self-actualization, the drive to fulfil one's full potential, was sketched from the lives of people the theory's author admired, among them Lincoln and Einstein.

Which German-American child psychoanalyst coined the phrase 'identity crisis'?

Erik Erikson is best known for his theory of psychosocial development; he taught at Harvard, Berkeley and Yale despite never earning a university degree.

The Milgram experiment of the early 1960s primarily investigated which psychological phenomenon?

Obedience to authority crumbled once defiance had company: when two fellow 'teachers', both actors, refused to go on, only 4 of 40 participants obeyed to the end.

In Freud's structural model, which agency is the unconscious source of bodily needs, impulses and desires?

The id is simply 'it' in Latin: Freud wrote 'das Es', the It, in plain German, and the Latin word was chosen by his English translators.

After his 1953 hippocampus surgery, patient H.M. famously lost which ability?

Forming new memories was beyond Henry Molaison after the operation, yet he got steadily better at mirror drawing with no recollection of having practised, showing that memory is not a single system.

In 1848 railroad foreman Phineas Gage survived what passing completely through his head?

An iron tamping rod over a metre long shot through Gage's skull as he packed blasting powder; he stayed conscious and lived another 12 years, though friends said he was 'no longer Gage'.

In the Stroop test, what happens when you must name the ink colour of the word 'red' printed in blue?

You slow down because reading is so automatic that the word 'red' gets in the way of saying 'blue'; John Ridley Stroop published the effect in 1935.

The Dunning–Kruger effect describes people with low ability in a specific area tending to do what?

People overrate their own skill when they lack it in a specific domain; the original study tested logical reasoning, grammar and humour, and the effect is often misread as 'stupid people are overconfident'.

George Miller's 'magical number seven, plus or minus two' describes the capacity of which memory system?

Short-term memory holds about seven items, Miller argued in 1956; later research found the limit is nearer four once people are prevented from grouping items into larger chunks.

Which sleep stage is nicknamed 'paradoxical sleep' because the brain looks almost as active as when awake?

REM sleep is when most dreaming happens; the paradox is that while the brain races, the arm and leg muscles are temporarily paralysed, which stops sleepers acting out their dreams.

In a famous 1974 car-crash study, which verb for what the cars did produced the highest speed estimates?

'Smashed' drew estimates averaging about 41 mph against 34 mph for 'hit', though everyone watched the same film: evidence that the wording of a later question can reshape the memory itself.

Children who held out longest in Stanford's marshmallow test went on to score higher on which exam?

The SAT link came from a 1990 follow-up of the preschoolers; a 2018 study found that family income and home life explained much of it, so the wait was no pure test of willpower.

Which German psychologist produced the 'forgetting curve' by memorising nonsense syllables?

Hermann Ebbinghaus used himself as the only subject, inventing some 2,300 meaningless syllables so that nothing he already knew could help him remember them.

The Zeigarnik effect says which kind of task sticks best in memory?

Interrupted ones: Bluma Zeigarnik reported in 1927 that people recalled tasks they were stopped from finishing better than completed ones; the idea is said to have come from a waiter who forgot each order once it was paid.

Which effect leads people to assume an attractive person must also be clever and kind?

The halo effect was named in 1920 after army officers' ratings of their men's physique, intelligence, leadership and character turned out to rise and fall together far too neatly.

The mere-exposure effect predicts that people come to like things simply because the things are what?

Familiar things win us over even when we don't know we have met them before: in Robert Zajonc's experiments, people came to prefer images that had been flashed too briefly to recognise.

Damage to Broca's area, in the frontal lobe of the dominant hemisphere, typically impairs what?

Speech production was all but lost in Paul Broca's 1861 patient, nicknamed 'Tan' because that was the one syllable he could say, although he still understood what was said to him.

Blindsight, responding to objects one insists one cannot see, follows damage to which part of the eye-to-brain pathway?

Blindsight follows damage to the primary visual cortex (V1); Lawrence Weiskrantz coined the oxymoron after patients told to 'guess' at things in their blind field did far better than chance.

A person with Capgras delusion believes that someone close to them has been what?

Replaced by a double: sufferers still recognise a parent's or partner's face, but one theory is that the feeling that should come with it is missing, so the brain concludes the person must be an impostor.

V. S. Ramachandran's mirror box was devised to ease which condition?

Phantom-limb pain was the target: the mirror shows the intact limb's reflection where the missing one should be, so the patient sees the phantom move; Ramachandran introduced the box in the 1990s.

The 'cocktail party effect' is the brain's ability to do what?

To follow one voice in a noisy room the brain filters out the rest, yet about a third of listeners still catch their own name when it crops up in a conversation they were ignoring.

Which bias did a rigged wheel of fortune reveal when its random number swayed people's later estimates?

Anchoring: the wheel was fixed to stop at 10 or 65, and people then put the share of African countries in the United Nations at about 25% or 45%; the pull holds even when people know the number is arbitrary.

In 1879 Wilhelm Wundt founded the first formal laboratory for psychological research at which university?

Leipzig's laboratory drew students from across Europe and America, and visitors such as G. Stanley Hall carried its methods home, where Hall opened a psychology laboratory of his own in 1883.

Which psychologist invented the operant conditioning chamber, better known by his name?

B. F. Skinner built the first box as a Harvard graduate student; during World War II he ran a secret project training pigeons to steer a missile by pecking at an image of its target.

Whose infant rhesus monkeys chose a cloth surrogate mother over a wire one holding food?

Harry Harlow's monkeys spent their time clinging to the cloth mother and visited the wire one only to feed, overturning the view that infants bond with whoever feeds them.

Which psychologist designed the "strange situation" procedure to observe infant attachment?

Mary Ainsworth first watched mothers and babies in Uganda, then in Baltimore; in her laboratory routine the mother twice leaves the room, and observers watch how the baby greets her return.

Which fourth infant attachment style did Main and Solomon add to secure, avoidant and ambivalent?

Disorganized attachment, added in 1986, describes infants who freeze or approach and then pull away; it is often linked to a caregiver who is frightening as well as the child's only refuge.

Attachment theory was first developed by which British psychiatrist and psychoanalyst?

John Bowlby reached the theory after finding that many young thieves at his clinic had been separated from their mothers early, then reporting on homeless children for the World Health Organization in 1951.

Which Soviet psychologist introduced the "zone of proximal development"?

Lev Vygotsky introduced the zone of proximal development in the early 1930s; after his death from tuberculosis in 1934 his books were suppressed in the USSR until the mid-1950s.

Which Austrian doctor coined the term "inferiority complex" and founded individual psychology?

Alfred Adler was president of Freud's Vienna Psychoanalytic Society in 1910, then walked out the next year with a group of followers to found a rival school of his own.

Which German psychoanalyst is credited with founding feminist psychology?

Karen Horney, born near Hamburg in 1885, traced differences between the sexes to society and culture rather than biology, answering Freud's 'penis envy' with her own 'womb envy'.

Sigmund Freud's youngest child, who pioneered child psychoanalysis in London, was named what?

Anna Freud, the youngest of six children, escaped Nazi-occupied Vienna with her ailing father in 1938 and went on to found a child-therapy clinic in Hampstead that now bears her name.

Which thinker, dubbed the "father of American psychology", wrote The Principles of Psychology?

William James published The Principles of Psychology in 1890; trained as a physician, he never practised medicine, and co-founded pragmatism with Charles Sanders Peirce.

Which personality theorist had 26 papers ruled 'unsafe' by a King's College London enquiry?

Hans Eysenck's papers with Ronald Grossarth-Maticek claimed that a 'cancer-prone' personality predicted who would die of the disease; in 2019 King's judged them not scientifically rigorous and wrote to the journals that had published them.

Which memory researcher developed the "lost in the mall" false-memory technique?

Elizabeth Loftus's 1995 study with Jacqueline Pickrell slipped the invented story in among true childhood events supplied by relatives; about a quarter of the 24 subjects came to 'remember' it.

Which British psychologist devised the four-card selection task testing conditional reasoning?

Peter Wason published the puzzle in 1966: most people turn over the cards that fit the rule and overlook the one that could disprove it, and it became one of the most studied puzzles in reasoning.

Who began learned-helplessness research in 1967 and later founded positive psychology?

Martin Seligman began learned-helplessness experiments with dogs in 1967 and made positive psychology the theme of his 1998 term as American Psychological Association president.

Which longtime research partner of Daniel Kahneman died six years before Kahneman's 2002 Nobel Prize?

Amos Tversky formulated prospect theory with Kahneman, but a Nobel Prize cannot be awarded posthumously, so only Kahneman could be honoured for the work the two had done together.

Which 2011 Kahneman bestseller summarised his research on two modes of thought?

Thinking, Fast and Slow (2011) contrasts fast, intuitive System 1 with slow, effortful System 2, labels Kahneman borrowed from psychologists Keith Stanovich and Richard West.

Which disorder did Swiss psychiatrist Eugen Bleuler rename from 'dementia praecox'?

Schizophrenia was coined from Greek roots meaning 'a splitting of the mind', and the name has left it widely confused with split personality, a different condition.

Which psychologist introduced the concept of 'flow' in a 1975 book?

Mihály Csíkszentmihályi came to the idea by studying painters so absorbed in their work that they ignored hunger and sleep, and for whom the act of painting mattered more than the finished canvas.

Operant conditioning originated with which psychologist's "law of effect"?

Edward Thorndike timed hungry cats escaping from puzzle boxes: moves that happened to open the latch came quicker each trial, so he concluded that satisfying results 'stamp in' a behaviour.

Children in a famous 1961 study copied adults attacking which toy?

The Bobo doll was inflatable; children who had watched an adult punch it and hit it with a mallet did the same when left to play, with no reward for copying, a sign that children learn such acts simply by watching.

Which 1954 summer-camp experiment set the Rattlers against the Eagles?

Robbers Cave is an Oklahoma state park where Muzafer Sherif's team posed as camp staff; simply bringing the feuding groups together did not help, and peace came only with tasks that neither could manage alone.

Which effect, named after a 1920s Chicago-area factory study, describes people changing their behaviour when watched?

The Hawthorne effect is named for Western Electric's Hawthorne Works in Cicero, Illinois; when economists dug out the original lighting data decades later, the famous productivity jump was largely missing.

Which book by Rosenthal and Jacobson claimed teachers' expectations shape student performance?

Pygmalion in the Classroom (1968) reported that pupils picked at random and described to their teachers as likely to 'bloom' gained more IQ points; its title borrows the myth of the sculptor whose statue came to life.

Which effect explains why people rate vague, horoscope-style personality sketches as strikingly accurate descriptions of themselves?

The Barnum effect was shown by Bertram Forer, who handed every student the same 'personal' profile, lifted from newsstand astrology, and saw them rate it above 4 out of 5; Paul Meehl later named it after the showman.

Being fined $100 stings about twice as much as finding $100 pleases, a bias that behavioural economists call what?

Loss aversion is a pillar of prospect theory, set out in 1979: because losses loom about twice as large as equal gains, people cling to what they have rather than gamble on getting something better.

Stockholm syndrome is named after a 1973 hostage siege inside what?

A bank: four Kreditbanken employees were held in its vault for six days in August 1973, and one told Sweden's prime minister by phone that she trusted her captors and feared a police assault.

Which developmental psychologist proposed six stages of moral reasoning in three levels?

Lawrence Kohlberg built the stages from interviews with boys only; his colleague Carol Gilligan answered in 1982 with In a Different Voice, arguing that girls' moral reasoning turns on care and responsibility for others.

In the Heinz dilemma, a classic test of moral reasoning, what does Heinz steal to save his dying wife?

A drug: the druggist charged ten times what it cost him to make and refused the half Heinz had managed to raise, so Heinz broke in; answers are scored on the reasoning, not on the yes or no.

Which term describes better recall of the last items in a list?

The recency effect is fragile: make people count aloud for 30 seconds before recalling and it vanishes, while the first items on the list are remembered as well as before.

Baddeley and Hitch's 1974 model, with its central executive and phonological loop, describes which kind of memory?

Working memory displaced the idea of a single temporary store in 1974, when Baddeley and Hitch found that people holding a string of digits in their heads could still reason and follow prose with little trouble.

A brain cell that fires both when an animal acts and when it watches the same act is called what?

A mirror neuron was first recorded in Parma, where cells that fired as a macaque grasped a piece of food also fired when it merely watched an experimenter pick the food up.

Which psychiatrist is regarded as the father of cognitive therapy?

Aaron Beck trained as a psychoanalyst and expected his depression research to confirm psychoanalytic theory; instead he found patients beset by automatic negative thoughts, and built a therapy around testing them.

Albert Ellis founded which approach, abbreviated REBT?

Rational emotive behavior therapy had a trial run on its founder: at 19, Ellis attacked his fear of rejection by making himself strike up conversations with women he saw alone in the Bronx Botanical Garden.

Which Portuguese neurologist shared a 1949 Nobel Prize for developing the lobotomy?

António Egas Moniz did not do the operating himself: his colleague Almeida Lima carried it out under his direction, first by injecting alcohol into the frontal lobes, then with a wire-loop instrument made for the job.

Which sister of John F. Kennedy was lobotomised in 1941 at age 23?

Rosemary Kennedy lost most of her ability to walk and speak, and spent most of her remaining years in care in Wisconsin; her sister Eunice went on to found the Special Olympics.

Which 19th-century American reformer lobbied state legislatures to build asylums for the mentally ill?

Dorothea Dix began in 1841 after teaching a Sunday class in a Massachusetts jail, where she found mentally ill inmates kept without heat; she toured the state's jails and put her findings before the legislature.

The 1973 Rosenhan experiment on psychiatric diagnosis was published under what title?

On Being Sane in Insane Places reported a second test: a hospital warned to expect more pseudopatients rated 41 of 193 new arrivals as likely fakes, though Rosenhan had sent none.

Scottish surgeon James Braid popularised which word in the 1840s, built on the Greek for sleep?

Hypnotism is short for Braid's 'neuro-hypnotism', or nervous sleep; the name stuck even though the trance resembles sleep only on the surface, with attention narrowed rather than switched off.

Max Wertheimer's 1912 study of the phi phenomenon, which launched Gestalt psychology, used flashing lights to create an illusion of what?

Motion is said to have caught Wertheimer's attention on a 1910 train journey: the story goes that he got off at Frankfurt and bought a toy stroboscope to test how separate flashes could seem to move.

Cornell psychologist Edward Titchener introduced which English word in 1909 to translate the German Einfühlung, "feeling into"?

Empathy began in German aesthetics, as a word for feeling one's way into a work of art rather than into another person; Titchener modelled his English version on 'sympathy'.

Mary Whiton Calkins completed every requirement for a psychology PhD in 1895, but which university refused her the degree as a woman?

Harvard was not the end of it: in 1902 its sister college Radcliffe offered Calkins a doctorate instead and she turned it down; in 1905 she became the first woman to lead the American Psychological Association.

In the five stages of grief set out by Elisabeth Kübler-Ross in 1969, which stage is listed straight after denial?

Anger comes second on the list, but Kübler-Ross drew the stages from interviews with dying patients, not the bereaved, and said they need not arrive in that order.

Kenneth and Mamie Clark's 1940s doll studies contributed to which landmark Supreme Court ruling?

Brown v. Board of Education cited the doll tests in its footnote 11: most of the Black children preferred a white doll and called it the nice one, which the Clarks read as the damage done by segregation.

Stanley Milgram began his famous Yale experiment in 1961, months after which trial opened in Jerusalem?

Adolf Eichmann's trial opened in April 1961, the year after Israeli agents seized him near his home outside Buenos Aires and smuggled him out of Argentina; Milgram's first sessions at Yale followed that summer.

How did Leon Festinger's team study the doomsday group in When Prophecy Fails?

Joining it undercover, the researchers and their hired observers posed as believers in flying saucers to win the group's trust, without telling its members they were being studied.

Whose 1964 murder, reportedly ignored by dozens of neighbours, inspired research into passive witnesses?

Kitty Genovese was killed in Kew Gardens, Queens; the newspaper story that 38 neighbours watched and did nothing was grossly exaggerated, as the paper itself conceded in 2016.

Irving Janis used the Bay of Pigs fiasco to illustrate which term for stifled dissent?

Groupthink was modelled on Orwell's 'doublethink' and was in print by 1952; Janis made it a theory in 1972, arguing that Kennedy advisers with doubts about the invasion plan kept quiet to preserve the team's unity.

In the Müller-Lyer illusion, two equal lines look different in length because of what drawn at their ends?

Arrowheads pointing in or out make equal lines look shorter or longer; one leading explanation is that the brain reads them as the near and far corners of rooms and buildings and adjusts the length to match.

Chabris and Simons' invisible gorilla study asked viewers to count passes of what?

Viewers counted basketball passes by the white-shirted team and about half never noticed the person in a gorilla suit; Simons and Chabris published it in 1999 and won a 2004 Ig Nobel.

Gordon Gallup's 1970 mirror test first showed which animals recognising their own reflection?

Chimpanzees given a mirror for days were marked with red dye while anaesthetised; on waking they touched the marks while watching their reflection, and the monkeys Gallup tried never did.

Which philosopher originally conceived the Sally-Anne false-belief test?

Daniel Dennett proposed the false-belief paradigm in a 1978 commentary; Wimmer and Perner ran the first version in 1983, and Baron-Cohen, Leslie and Frith named the doll-based Sally-Anne test in 1985.

The Myers-Briggs personality test grew out of which 1921 Carl Jung book?

Psychological Types reached Katharine Briggs in English in 1923; she had been building her own scheme of personalities and swapped her categories for Jung's, and her daughter Isabel later turned them into a questionnaire.

Modern IQ tests are scaled to a mean of 100 and a standard deviation of what?

15 points is the standard deviation, so about two-thirds of people score between 85 and 115; the 'quotient' in IQ is a relic of early tests that divided mental age by actual age.

The long-running rise in IQ scores across the 20th century is named after which researcher?

James Flynn, a philosopher at New Zealand's University of Otago, spotted the pattern in old test manuals: people who took both an old and a renormed test scored higher on the old one, a gain of about three points a decade.

Whose 1995 bestseller popularised the term "emotional intelligence"?

Daniel Goleman was a science journalist at The New York Times; his bestseller took its title from a term that psychologists Peter Salovey and John Mayer had defined in a 1990 paper.

Howard Gardner introduced multiple intelligences in which 1983 book?

Frames of Mind argued for seven separate intelligences, each of which had to pass tests such as being knocked out on its own by brain damage or showing up in isolation in savants and prodigies.

Which 1988 film character was inspired by savant Kim Peek?

Raymond Babbitt in Rain Man was modelled on Peek, who was born without the bundle of nerves that links the brain's two halves and could read two pages at once, one with each eye.

Which term describes the inability to voluntarily visualise mental images?

Aphantasia got its name in 2015, after a 65-year-old man told neurologist Adam Zeman that his mind's eye had gone blank following minor surgery and others then came forward who had never had one.

Face blindness is known medically by what name?

Prosopagnosia, from the Greek for face, afflicted the neurologist Oliver Sacks, who wrote that he had more than once apologised for nearly bumping into a large bearded man who turned out to be his own reflection.

Cotard's syndrome involves the delusion that one is what?

Dead, or missing their organs or blood: the belief can be so firm that patients stop eating, which makes the delusion dangerous as well as strange.

Alien hand syndrome is nicknamed after which film character?

Dr. Strangelove, Peter Sellers's character in the 1964 film, has a black-gloved hand that snaps into salutes against his will; real patients describe a hand that moves as if somebody else were controlling it.

Which trait completes the "dark triad" alongside narcissism and psychopathy?

Machiavellianism was defined in the 1960s by psychologists Richard Christie and Florence Geis, who wrote the kind of cynical statements they thought Machiavelli might make and measured how strongly people agreed.

Freud's slips of the tongue were analysed in which 1901 book?

The Psychopathology of Everyday Life opens with Freud's own lapse: travelling in the Balkans, he could not recall the painter Signorelli, and the wrong names Botticelli and Boltraffio kept coming instead.

Which researcher's 2012 TED talk made "power posing" famous before the effect failed to replicate?

Amy Cuddy's 2012 TED talk on power posing drew tens of millions of views; co-author Dana Carney issued a 2016 statement distancing herself from the finding after failed replications.

Which Stanford psychologist is known for the concept of "mindset" and motivation research?

Carol Dweck's best-known experiment gave schoolchildren one line of praise after an easy test: most of those praised for effort then chose a harder test, while most praised for being smart took the easy one.

Which behavioral economist, co-author of the bestseller Nudge, won the 2017 Nobel Memorial Prize in Economic Sciences?

Richard Thaler won for showing how predictably people stray from rational decisions about money; asked what he would do with the prize, he said he would spend it as irrationally as possible.

What did Masahiro Mori call our unease at robots that look almost human?

The uncanny valley translates Mori's bukimi no tani; his 1970 essay went almost unnoticed for decades, and its advice to designers was to stop short of lifelike rather than risk the dip.

The frequency illusion is also named after which militant group?

The Baader-Meinhof phenomenon was named in 1994 by a reader of the St. Paul Pioneer Press, who noticed the German group's name cropping up again soon after first coming across it.

Under Fechner's law, each doubling of a stimulus adds the same step of sensation, making sensation which function of stimulus energy?

The logarithm law grew from a flash of insight Gustav Fechner had in 1850 about measuring sensation against stimulus, an anniversary that psychophysicists still mark as Fechner Day.

Which theory of crime, named in a 1982 Atlantic article, drew on Philip Zimbardo's experiment with abandoned cars?

Broken windows theory borrowed its image from Zimbardo's 1969 test: a car left in the Bronx was stripped at once, while one in Palo Alto stood untouched for a week until he took a sledgehammer to it and passers-by joined in.

In Schachter and Singer's 1962 emotion experiment, subjects told they were testing an eyesight treatment were in fact given which hormone?

Adrenaline, also called epinephrine, left them aroused without knowing why, so they took their cue from a planted companion: giddy beside a clowning one, irritable beside a fuming one.

Which compliance technique gets a person to agree to a large request by first having them agree to a modest one?

Foot-in-the-door: an early study first asked California housewives a few product questions, then to let men search their cupboards.

Which Stanford psychologist conducted the 1970 marshmallow experiment on delayed gratification?

Walter Mischel watched preschoolers at Stanford's Bing Nursery School resist the treat by covering their eyes, singing to themselves and even trying to nap; his own three daughters attended the school.

Julian Rotter's 1966 scale measures whether people credit outcomes to themselves or to luck, a trait called what?

Locus of control grew out of Rotter's work in the 1950s; later studies found that 'internals', who credit their own actions, tend to achieve more at school and at work than 'externals'.

In a 1993 study, most people chose to repeat the longer of two cold-water trials because it finished milder, illustrating what?

The peak-end rule also held in hospital: patients whose colonoscopy was drawn out with a gentler final stretch rated the whole procedure as less unpleasant and were somewhat more likely to come back for another.

The famous 1998 illusion that makes people feel a fake hand is their own is named after a hand made of what?

Rubber: with the real hand hidden and both stroked in time with a paintbrush, people came to feel the fake one as their own, and reached toward it when asked to point to their real hand.

Which 2004 Barry Schwartz book contrasts 'maximizers' with 'satisficers'?

The Paradox of Choice leans on a supermarket test in which shoppers offered 6 jams to taste were far more likely to buy a jar than shoppers offered 24.

The 'Tetris effect' describes what happening after long stretches of playing Tetris?

Thoughts and dreams fill with falling shapes even without any memory of the game: in a 2000 sleep study, amnesic patients who could not recall playing still saw the pieces as they drifted off.

Which French term names the opposite of déjà vu, when a well-known word or place suddenly feels strange?

Jamais vu, 'never seen', can be induced on demand: volunteers asked to write the word 'door' over and over soon began to doubt it was a real word, a study that later won an Ig Nobel Prize.

Thomas Gilovich and colleagues coined which term in 1999 for overrating how much others notice us?

The spotlight effect was demonstrated with students made to wear an embarrassing Barry Manilow T-shirt into a room of classmates; they greatly overestimated how many had noticed whose face was on it.

The word 'bedlam', meaning uproar and confusion, began as the nickname of which kind of medieval London institution?

A psychiatric hospital, Bethlem Royal, gave the language its word for chaos when Londoners slurred its old name, Bethlehem. Founded as a priory in 1247, it was housing the insane by the early 1400s.

Which superhero was created by William Moulton Marston, a psychologist who helped invent an early lie detector?

Wonder Woman binds villains with a magic lasso that makes them tell the truth. Marston and his wife Elizabeth Holloway invented an early prototype of the polygraph.

A 1993 study of 36 college students sparked the popular myth that listening to which composer makes babies smarter?

Mozart lifted the students' spatial reasoning for only about a quarter of an hour. In 1998 Georgia's governor still proposed giving every newborn a tape or CD of classical music.

Clever Hans, who seemed to do arithmetic in 1900s Germany while really reading his trainer's cues, was what animal?

A horse fooled a nation until psychologist Oskar Pfungst showed in 1907 that Hans was only watching his trainer's reactions. Unintended cueing by researchers is still called the Clever Hans effect.

Which 18th-century physician's theory of 'animal magnetism' gave English a verb meaning to hold someone spellbound?

Franz Mesmer's healing craze became known as mesmerism, and by 1862 'mesmerize' also meant to enthral. King Louis XVI ordered an investigation of his claims in 1784.

When a Monte Carlo roulette wheel hit black 26 times running in 1913, bettors lost millions to which reasoning error?

Gambler's fallacy is the belief that a streak makes the opposite outcome 'due'. The crowd kept betting against black, sure that a long run of red had to follow.

Stanley Milgram's 1967 small-world study of chains of acquaintances is tied to how many degrees of separation?

Six is the number the study is remembered for, yet Milgram never used the phrase 'six degrees of separation'. Playwright John Guare is its most likely populariser.

During World War I, soldiers with symptoms now linked to post-traumatic stress disorder were said to have what?

Shell shock got its name because doctors first blamed exploding artillery shells for the tremors, amnesia and other symptoms. Charles Myers put the term in print in The Lancet in 1915.

In the title of neurologist Oliver Sacks's 1985 book, a man with visual agnosia mistakes his wife for what?

A hat is what the patient, a music teacher, took his wife's head for as he left the consulting room. Michael Nyman turned the case into an opera in 1986.

Which condition, in which people feign illness for attention, is named after a fictional baron famous for tall tales?

Munchausen syndrome was named in 1951 by physician Richard Asher, writing in The Lancet. Critics objected that borrowing a comic storyteller's name was disrespectful to patients.

Which neurotransmitter, central to the brain's reward system, runs short when neurons die in Parkinson's disease?

Dopamine rises at the mere anticipation of a reward, and many addictive drugs boost its release. L-DOPA, the chemical the body makes it from, is the most widely used Parkinson's treatment.

Which brain structure fine-tunes movement and balance and packs in more neurons than the rest of the brain combined?

Cerebellum is Latin for 'little brain', and it fills only about 10% of the brain's volume. Its tiny granule cells are so numerous that they outnumber the neurons everywhere else.

Which fatty insulation around nerve fibres speeds up electrical signals and is attacked in multiple sclerosis?

Myelin lets nerve impulses hop from gap to gap along a fibre instead of travelling as a slow continuous wave. Its fat content is what makes the brain's white matter white.

Which hormone, released by the adrenal glands under stress, peaks in the blood around the time of waking?

Cortisol surges just before or at waking, a daily spike known as the cortisol awakening response. It also climbs when blood sugar runs low.

Physiologist Walter Cannon gave which name to the body's surge of adrenaline and racing heart when danger appears?

Fight or flight began as Cannon's 1915 phrase 'the necessities of fighting or flight'. Even the pupils join in, widening for a better view of the surroundings.

Jet lag strikes when travel knocks which roughly 24-hour internal cycle out of step with local time?

Circadian rhythm is run by a master clock of cells in the hypothalamus, the suprachiasmatic nucleus. Daylight is the main signal that keeps it in step with the day.

Which sleep disorder causes daytime sleepiness and, in some people, sudden muscle weakness triggered by laughter?

Narcolepsy's collapses are called cataplexy and can follow laughter, anger or surprise. Type 1 narcolepsy stems from losing the neurons that make orexin, also called hypocretin.

Which sleep experience, named by psychiatrist Frederik van Eeden in 1913, lets sleepers know they are asleep?

Lucid dreaming can let the sleeper steer the characters and plot, though control is not its defining feature. Van Eeden chose 'lucid' to mean having insight, not vivid.

Which substance, which blocks the brain's adenosine receptors, is the world's most widely consumed psychoactive drug?

Caffeine is shaped enough like adenosine, one of the body's own sedating signals, to sit in its receptors and block them. Unlike most psychoactive drugs it is legal almost everywhere.

Rod cells, which outnumber cone cells in the human retina about twenty to one, are specialised for which conditions?

Dim light is where rods take over, which is why colours fade at dusk: rods play little part in colour vision. They are almost entirely responsible for seeing at night.

Which condition blends the senses, so that a person might see letters as coloured or hear a trumpet as orange?

Synesthesia comes from Greek words meaning 'together' and 'sensation'. Seeing letters or numbers as inherently coloured is one of its most common forms.

The Müller-Lyer illusion, drawn with inward and outward arrowheads, tricks viewers into misjudging what about two lines?

Their length is identical, yet the shaft tipped with arrow tails looks longer than the one with arrowheads. In a 17-culture study, San foragers of the Kalahari were the least fooled.

Which term describes seeing meaningful images in random patterns, such as the Man in the Moon or a face on Mars?

Pareidolia shows up in brain scans: objects that look like faces trigger the face-processing area within about 165 milliseconds, much as real faces do.

Eleanor Gibson and Richard Walk's 'visual cliff', a glass-covered drop, tested which ability in crawling infants?

Depth perception made babies hesitate or refuse to cross the glass toward their mothers. They patted the surface and knew it was solid, yet still would not crawl over the apparent drop.

A car's seatbelt alarm stops beeping once the driver buckles up, a use of which operant conditioning principle?

Negative reinforcement strengthens a behaviour by taking something unpleasant away, so it is not a punishment. Riders use it too, easing pressure on the reins when their mount obeys.

Goslings that trailed zoologist Konrad Lorenz as if he were their mother showed which rapid form of early learning?

Imprinting happens in a short critical period, which Lorenz put at 13 to 16 hours after hatching. His geese fixed on the first moving thing they saw, including his wading boots.

Which term did Roger Brown and James Kulik coin in 1977 for vivid recollections of hearing shocking public news?

Flashbulb memory feels like a snapshot but is not one: people quizzed three years after the Challenger explosion were highly confident and not very accurate.

Splitting a ten-digit phone number into three or four short groups is an example of which short-term recall strategy?

Chunking works because each small group is stored as a single unit, so more fits within short-term memory's limited capacity. Items are recalled more easily as a group than one by one.

Students who spread study over several days recall more than those who cram the night before, a finding known as what?

Spacing effect studies are strikingly one-sided: in a 2006 review, spaced practice beat cramming-style massed practice in 259 of 271 cases.

Which mnemonic technique, used by memory champions, places items along an imagined walk through a well-known place?

Method of loci is also called the memory palace. Legend credits the Greek poet Simonides, said to have named the victims of a collapsed banquet hall by recalling where each had sat.

The game of peekaboo is a classic test of which milestone in an infant's understanding of the physical world?

Object permanence is the understanding that things go on existing when they cannot be seen. Dogs, cats and food-storing magpies have been shown to have it too.

Which thinking shortcut leads people to overrate dangers that get heavy news coverage, such as airline accidents?

Availability heuristic means judging how common something is by how easily examples come to mind. It is why most people wrongly guess that more English words start with K than have K third.

Drug trials give one group dummy sugar pills to measure which phenomenon, in which expectation alone eases symptoms?

Placebo effect takes its name from the Latin for 'I shall be pleasing'. Some trials are now 'open-label', with patients told outright that the pill is inert.

Ice-cream sales and drownings both climb in summer, a textbook reminder that correlation does not imply what?

Causation is missing here because hot weather drives both: people buy more ice cream and swim more. The error has a Latin name meaning 'with this, therefore because of this'.

Max Ringelmann found that people pull a rope less hard in a team than alone, an early sign of which group effect?

Social loafing deepens as teams grow: the more people on Ringelmann's rope, the less of their maximum effort each one gave. A 1974 rerun used helpers who only pretended to pull.

Which Viennese psychiatrist drew on surviving Nazi concentration camps to write Man's Search for Meaning?

Viktor Frankl wrote the book in just nine days, and it went on to sell millions of copies. He also founded logotherapy, which treats the search for meaning as the central human drive.

Which psychoanalytic idea, describing a young boy's rivalry with his father, is named after a mythical king of Thebes?

Oedipus complex borrows the name of the Theban king who unknowingly killed his father and married his mother. The idea first appeared in The Interpretation of Dreams in 1899.

Which condition, once called manic depression, brings spells of abnormally elevated mood as well as deep lows?

Bipolar disorder's highs count as mania only when severe; a milder high that leaves daily functioning intact is called hypomania. Episodes can last days, weeks or even months.

Which illness was first diagnosed in Auguste Deter, a German patient who kept repeating 'I have lost myself'?

Alzheimer's disease is named for her doctor, Alois Alzheimer, who arranged free care for her in exchange for her medical records and her brain after death. She died in 1906 aged 55.

Which American linguist argued that children are born with an innate 'universal grammar' that makes language learnable?

Noam Chomsky's case rests on what he named the 'poverty of the stimulus': children do not hear rich enough speech to pick up every feature of their language without built-in help.

The 'hedonic treadmill' idea was tested in a 1978 study that compared paralysed accident victims with which group?

Lottery winners drifted back toward ordinary happiness once the thrill wore off, the pattern the treadmill predicts. The researchers interviewed 22 of them and 29 accident victims.

Norman Triplett's 1898 study of competition began when he noticed which athletes went faster in company than alone?

Cyclists rode faster beside a rival than alone, so Triplett tested the idea in a lab with 40 children winding fishing reels. Gordon Allport later called it the first experiment in social psychology.

The impatient, competitive 'Type A' personality was first described in the 1950s by two doctors from which specialty?

Cardiology supplied the clue: an upholsterer pointed out that the chairs in Meyer Friedman and Ray Rosenman's waiting rooms were worn only on the arms and front edge, as if patients could not sit still.

The Yerkes-Dodson law, published in 1908, plots performance on a hard task against arousal as a curve of which shape?

An inverted U means performance climbs with arousal, then falls once arousal gets too high. For simple, well-learned tasks the drop never comes: more arousal keeps helping.

Hans Selye's general adaptation syndrome traces prolonged stress through alarm, resistance and which final stage?

Exhaustion sets in only if the body fails to overcome the threat and runs down its physiological resources. The alarm stage comes first, switching on the sympathetic nervous system.

William Stern's original IQ formula, proposed in 1912, divided which quantity by a child's actual age?

Mental age was the age whose typical test tasks a child could pass, whatever the child's real age. Stern also coined the abbreviation 'IQ'.

Karl Duncker's classic test of functional fixedness asks people to fix which item to a wall using a box of thumbtacks?

A candle goes up once solvers see the tack box as a shelf rather than just a container. Some instead try tacking the candle straight to the wall or gluing it there with melted wax.

Which ability, to attribute beliefs and intentions to others, did a famous 1978 paper ask whether chimpanzees possess?

Theory of mind entered psychology through David Premack and Guy Woodruff's paper 'Does the chimpanzee have a theory of mind?'. Children typically come to grasp false beliefs between ages three and five.

Which element did Australian psychiatrist John Cade swallow himself before trying it on manic patients in the 1940s?

Lithium calmed his patients so strongly that Cade wondered whether mania was caused by a lack of it. His hunch began with injecting guinea pigs with patients' urine.

Claude Steele and Joshua Aronson's 1995 experiments showed test scores dropping under which group-based pressure?

Stereotype threat was first shown when African-American and European-American students sat a hard verbal section of the Graduate Record Examination. Some researchers link it to long-standing achievement gaps.