263 psychology ideas, each one credited to the book, paper or primary source it comes from. Free to read and swipe on Savvy.
Before estimating something, people exposed to an arbitrary number — even one from a spinning wheel — give answers pulled toward it. Experienced judges given a higher 'anchor' hand…
— Daniel Kahneman, Thinking, Fast and Slow
In experiments, most people refuse a coin flip unless they stand to win roughly double what they could lose. This asymmetry — loss aversion — quietly shapes everything from why we …
— Daniel Kahneman & Amos Tversky, Prospect Theory: An Analysis of Decision under Risk
A famous 1978 study compared lottery winners with people paralysed in accidents. Within a year or so, both groups had drifted back toward their old baseline of day-to-day happiness…
— Philip Brickman, Dan Coates & Ronnie Janoff-Bulman, Lottery Winners and Accident Victims: Is Happiness Relative?
In 1885, Hermann Ebbinghaus memorised thousands of nonsense syllables and tested himself for years. He found memory decays on a steep curve — but each well-timed review flattens it…
— Hermann Ebbinghaus, Über das Gedächtnis (Memory: A Contribution to Experimental Psychology)
Comparing primate brain sizes with their group sizes, Robin Dunbar predicted humans can maintain about 150 stable relationships. The number keeps turning up: Neolithic villages, Ro…
— Robin Dunbar, Neocortex size as a constraint on group size in primates
Decades of research on top performers found that raw hours barely matter. What matters is deliberate practice: working just beyond your ability, with immediate feedback, on your sp…
— Anders Ericsson & Robert Pool, Peak: Secrets from the New Science of Expertise
In 1954, Leon Festinger infiltrated a group that believed the world would end on a specific date. When the date passed uneventfully, the group didn't abandon its belief — it recrui…
— Leon Festinger, Henry Riecken & Stanley Schachter, When Prophecy Fails
Robert Zajonc showed that repeated exposure to a stimulus — a face, a shape, a nonsense word — reliably increases how much people like it, even when they don't consciously recognis…
— Robert Zajonc, Attitudinal Effects of Mere Exposure
In a study of colonoscopy patients, adding extra minutes of mild discomfort at the end of the procedure made people rate the whole experience as less unpleasant — even though they …
— Donald Redelmeier & Daniel Kahneman, Patients' Memories of Painful Medical Treatments: Real-time and Retrospective Evaluations of Two Minimally Invasive Procedures
In experiments, people who built their own IKEA boxes, origami or Lego sets valued their creations as highly as experts' work — and far more than identical items assembled by someo…
— Michael Norton, Daniel Mochon & Dan Ariely, The IKEA Effect: When Labor Leads to Love
Villanova and Temple researchers read college students trivia statements across three sessions two weeks apart. Statements repeated in later sessions were rated as more likely true…
— Lynn Hasher, David Goldstein, Thomas Toppino, Frequency and the Conference of Referential Validity
Given a disease expected to kill 600 people, most chose a certain option over a gamble when it was framed as 'saves 200 lives' — but chose the gamble when the identical option was …
— Amos Tversky, Daniel Kahneman, The Framing of Decisions and the Psychology of Choice
Rational choice says only future costs and benefits should matter — money already spent is gone either way. But people keep funding failing projects and finishing bad meals just be…
— Richard Thaler, Toward a Positive Theory of Consumer Choice
Ask someone to recall a list moments after hearing it and two patterns appear every time: the first few items are recalled best (primacy), the last few almost as well (recency), an…
— Bennet Murdock, The Serial Position Effect of Free Recall
Show someone the word 'blue' printed in red ink and ask them to name the ink color, not read the word — reaction time reliably increases and errors climb. John Ridley Stroop demons…
— John Ridley Stroop, Studies of Interference in Serial Verbal Reactions
In 1961, Stanley Milgram told volunteers to give an unseen 'learner' increasingly severe electric shocks every time he answered wrong. Despite cries of pain from the next room, 65%…
— Stanley Milgram, Behavioral Study of Obedience
In 1948, Bertram Forer gave students a personality test, then handed every single one of them an identical, vague profile lifted from a newsstand astrology column — and asked them …
— Bertram Forer, The Fallacy of Personal Validation: A Classroom Demonstration of Gullibility
Edward Thorndike found that when military officers rated soldiers on totally unrelated qualities — intelligence, leadership, physique — the scores were all suspiciously correlated.…
— Edward Thorndike, A Constant Error in Psychological Ratings
In 1999, Daniel Simons and Christopher Chabris had people count passes in a basketball video while a person in a gorilla suit walked through the middle of the court, stopped, and t…
— Daniel J. Simons and Christopher F. Chabris, Gorillas in Our Midst: Sustained Inattentional Blindness for Dynamic Events
Psychologist Bluma Zeigarnik noticed a waiter could recall every detail of unpaid orders but drew a blank once the bill was settled. Her 1927 experiments confirmed it: people remem…
— Bluma Zeigarnik, On Finished and Unfinished Tasks (Über das Behalten von erledigten und unerledigten Handlungen)
In a landmark 1956 paper, Harvard psychologist George Miller pulled together decades of experiments and found a recurring limit: people can hold roughly seven, plus or minus two, i…
— George A. Miller, The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information
Political scientist James Flynn documented that raw IQ test scores rose steadily across the 20th century in country after country, by roughly three points per decade. His 1984 anal…
— James R. Flynn, The Mean IQ of Americans: Massive Gains 1932 to 1978
Amos Tversky and Daniel Kahneman showed that people judge how common something is by how easily examples spring to mind, not by actual frequency. Vivid, widely reported events — a …
— Amos Tversky & Daniel Kahneman, Availability: A Heuristic for Judging Frequency and Probability
Researchers asked people to choose which of two faces they found more attractive, then handed back the opposite photo using a card trick. Most participants didn't notice the switch…
— Petter Johansson, Lars Hall, Sverker Sikström & Andreas Olsson, Failure to Detect Mismatches Between Intention and Outcome in a Simple Decision Task
Economists Colin Camerer, George Loewenstein and Martin Weber found that better-informed people systematically struggle to predict what less-informed people will think or do, even …
— Colin Camerer, George Loewenstein & Martin Weber, The Curse of Knowledge in Economic Settings: An Experimental Analysis
Daniel Kahneman, Jack Knetsch and Richard Thaler randomly handed out coffee mugs, then asked owners how much they'd sell for and non-owners how much they'd pay. Owners demanded rou…
— Daniel Kahneman, Jack L. Knetsch & Richard Thaler, Experimental Tests of the Endowment Effect and the Coase Theorem
Taking a test on material you just studied cements it in memory better than studying it again — even with no feedback on right or wrong answers. Henry Roediger and Jeffrey Karpicke…
— Henry L. Roediger III & Jeffrey D. Karpicke, The Power of Testing Memory: Basic Research and Implications for Educational Practice
Ask people how long a project will take and they'll lowball it — even after admitting past projects like it ran long. Daniel Kahneman and Amos Tversky named this the 'planning fall…
— Daniel Kahneman & Amos Tversky, Intuitive Prediction: Biases and Corrective Procedures
A single scathing review can outweigh a dozen glowing ones in memory, and it isn't just a feeling. Roy Baumeister and colleagues found bad events, bad feedback and negative impress…
— Roy F. Baumeister, Ellen Bratslavsky, Catrin Finkenauer & Kathleen D. Vohs, Bad Is Stronger Than Good
Show someone a list of similar items with one oddball mixed in, and that oddball is what they remember days later. German psychiatrist Hedwig von Restorff documented this in 1933: …
— Hedwig von Restorff, Über die Wirkung von Bereichsbildungen im Spurenfeld
In 1968 John Darley and Bibb Latané staged fake emergencies and found bystanders grew less likely to intervene as the group grew, since each assumes someone else will act. The effe…
— John M. Darley and Bibb Latané, Bystander Intervention in Emergencies: Diffusion of Responsibility
Confirmation bias is the tendency to search for, favour and recall information that supports what you already believe, while giving less weight to evidence against it. Raymond Nick…
— Raymond S. Nickerson, Confirmation Bias: A Ubiquitous Phenomenon in Many Guises
In 1953 Colin Cherry played two different spoken messages into each ear at once and asked listeners to repeat back just one. They followed the chosen message easily and were almost…
— E. Colin Cherry, Some Experiments on the Recognition of Speech, with One and with Two Ears
Placebos contain no active ingredient, yet across countless trials patients given them report real reductions in pain, nausea and other subjective symptoms — driven by expectation,…
— Henry K. Beecher, The Powerful Placebo
Hermann Ebbinghaus documented in 1885 that memories fade fastest right after learning, and that spacing repetitions apart preserves them far better than repeating them back to back…
— Hermann Ebbinghaus, Spacing effect
Once your brain flags a word, name or idea as newly relevant, selective attention makes you notice it far more often, and confirmation bias makes each sighting feel like proof it's…
— Arnold Zwicky, Frequency illusion
In 1913, French engineer Max Ringelmann had men pull on a rope alone and in groups, measuring the rope's tension each time. Individual effort dropped steadily as group size grew, f…
— Max Ringelmann, Ringelmann effect
In a 1975 experiment, divers memorised word lists either on a beach or several metres underwater, then were tested for recall in both environments. Recall was consistently better w…
— Duncan Godden and Alan Baddeley, Context-dependent memory in two natural environments: on land and underwater
Solomon Asch asked participants to match line lengths — an unambiguous, easy task. But when several actors in the room confidently gave the same wrong answer first, real participan…
— Solomon Asch, Asch conformity experiments
Karl Duncker's 1945 candle problem asks people to fix a lit candle to a wall using only a candle, a box of thumbtacks and a box of matches, without dripping wax on the table below.…
— Karl Duncker, On Problem Solving
Elizabeth Loftus and John Palmer showed people footage of a car accident, then asked how fast the cars were going when they 'smashed', 'collided', 'bumped' or 'hit' each other. The…
— Elizabeth Loftus and John Palmer, Reconstruction of Automobile Destruction
After a banquet hall collapsed and crushed the guests beyond recognition, the poet Simonides of Ceos reportedly identified each body by recalling exactly where they'd been sitting.…
— Marcus Tullius Cicero, De Oratore
When the sound of one syllable is dubbed onto video of a mouth saying a different one, most people perceive a third syllable that matches neither the audio nor the video alone. It …
— Harry McGurk & John MacDonald, Hearing Lips and Seeing Voices
In a classic study, people who chose their own lottery number demanded far more money to sell their ticket back than people who were simply given one — even though the odds were id…
— Ellen Langer, The Illusion of Control
Ask someone to judge whether a word is printed in capital letters and they'll barely remember it later. Ask them whether it fits a sentence's meaning instead, and recall jumps shar…
— Fergus Craik & Robert Lockhart, Levels of Processing: A Framework for Memory Research
Adding one candle to a dark room feels dramatic; adding one candle to a room with ninety-nine barely registers. Human perception scales with the proportional change in a stimulus, …
— Gustav Fechner, building on Ernst Weber, Elemente der Psychophysik
In a classic experiment, children who already loved drawing were split into groups: some got an expected reward for drawing, some got an unexpected reward, and some got none. Only …
— Mark R. Lepper, David Greene & Richard E. Nisbett, Undermining Children's Intrinsic Interest with Extrinsic Reward: A Test of the 'Overjustification' Hypothesis
Researchers asked homeowners to place a small 'Be a safe driver' sign in their window; nearly all agreed. Two weeks later, a different researcher asked a much bigger favor — a larg…
— Jonathan L. Freedman & Scott C. Fraser, Compliance Without Pressure: The Foot-in-the-Door Technique
Read a list of words like bed, rest, awake, tired, dream, wake, snooze — and most people will later swear they also heard the word 'sleep,' even though it never appeared. This robu…
— Henry L. Roediger III & Kathleen McDermott, Creating False Memories: Remembering Words Not Presented in Lists
People systematically overestimate how many others share their own beliefs, habits and choices. In a classic 1977 study, Stanford students who agreed to wear an advertising sandwic…
— Lee Ross, David Greene & Pamela House, The 'False Consensus Effect': An Egocentric Bias in Social Perception and Attribution Processes
In a 1998 study, researchers had someone stop a pedestrian to ask for directions. Seconds later, a door carried between them by two "workers" briefly blocked the view — and a compl…
— Daniel J. Simons and Daniel T. Levin, Failure to Detect Changes to People During a Real-World Interaction
Researchers had a student wear a T-shirt with an embarrassing image into a room of strangers, then asked the wearer to guess what fraction of people had noticed it. Wearers guessed…
— Thomas Gilovich, Victoria Husted Medvec, and Kenneth Savitsky, The Spotlight Effect in Social Judgment: An Egocentric Bias in Estimates of the Salience of One's Own Actions and Appearance
In 1976, a US judge ruled that Harrison's 'My Sweet Lord' infringed the Chiffons' 'He's So Fine' — not through deliberate theft, but because the earlier melody had lodged in his me…
— Judge Richard Owen, U.S. District Court (S.D.N.Y.), Bright Tunes Music Corp. v. Harrisongs Music, Ltd.
Across more than a hundred studies, people consistently recognise faces from their own race more accurately than faces from other races, mistaking cross-race strangers for each oth…
— Christian A. Meissner and John C. Brigham, Thirty Years of Investigating the Own-Race Bias in Memory for Faces: A Meta-Analytic Review
In 1920, John B. Watson and Rosalie Rayner paired a loud, startling noise with a tame white rat shown to an infant known as "Little Albert," who initially showed no fear of it. Aft…
— John B. Watson and Rosalie Rayner, Conditioned Emotional Reactions
Starting in 1958, psychologist Harry Harlow raised infant rhesus monkeys with two surrogate mothers: a bare wire frame that dispensed milk, and a soft cloth-covered frame with no f…
— Harry F. Harlow, The Nature of Love
In 1967, Martin Seligman and Steven Maier found that dogs first exposed to inescapable shocks later failed to escape shocks they could easily have avoided — they simply lay down an…
— Martin E. P. Seligman and Steven F. Maier, Failure to Escape Traumatic Shock
In Albert Bandura's 1961 Bobo doll experiment, children who watched an adult attack an inflatable clown doll imitated the exact aggressive acts when later left alone with it, while…
— Albert Bandura, Dorothea Ross, Sheila A. Ross, Transmission of Aggression through Imitation of Aggressive Models
In 1908, Robert Yerkes and John Dodson found mice learned a maze fastest under moderate electric-shock stress — too little left them unmotivated, too much made them frantic and err…
— Robert M. Yerkes, John D. Dodson, The Relation of Strength of Stimulus to Rapidity of Habit-Formation
Told that Linda is a philosophy graduate outspoken about social justice, most people rated 'bank teller and active feminist' as more likely than 'bank teller' alone — even though a…
— Amos Tversky, Daniel Kahneman, Extensional versus Intuitive Reasoning: The Conjunction Fallacy in Probability Judgment
Muzafer Sherif put people alone in a dark room and asked how far a stationary pinpoint of light seemed to drift — an illusion with no real answer. Individual estimates varied wildl…
— Muzafer Sherif, The Psychology of Social Norms
Researchers asked students to volunteer as counsellors for juvenile delinquents two hours a week for two years — almost everyone refused. But when that huge ask was followed by a f…
— Robert B. Cialdini et al., Reciprocal Concessions Procedure for Inducing Compliance: The Door-in-the-Face Technique
In 1736, Benjamin Franklin won over a hostile rival legislator by asking to borrow a rare book, not by doing him a favor. Having gone out of their way to help someone they were inc…
— Jon Jecker and David Landy, Liking a Person as a Function of Doing Him a Favour
In early-1900s Germany, a horse named Hans appeared to solve arithmetic by tapping out answers with his hoof. Psychologist Oskar Pfungst discovered in 1907 that Hans had no number …
— Oskar Pfungst, Clever Hans (The Horse of Mr. Von Osten): A Contribution to Experimental Animal and Human Psychology
Psychologist Melvin Lerner found that people have a deep need to believe the world is fair, where good things happen to good people and bad things happen to bad ones. Rather than a…
— Melvin J. Lerner, The Belief in a Just World: A Fundamental Delusion
When a weapon is visible during a crime, eyewitnesses fixate on it and remember far less about everything else, including the perpetrator's face. In a classic 1987 study, Elizabeth…
— Elizabeth F. Loftus, Geoffrey R. Loftus, and Jane Messo, Some Facts About Weapon Focus
In 1954, researchers split 22 boys into two camp groups that turned hostile within days of competing for prizes — raiding cabins, burning flags. Talking it out didn't help. Only ta…
— Muzafer Sherif, O.J. Harvey, B. Jack White, William Hood, Carolyn Sherif, Intergroup Conflict and Cooperation: The Robbers Cave Experiment
In a 1967 study, people read a pro- or anti-Castro essay and were told outright that the writer had been assigned which side to argue, no choice involved. They still rated the writ…
— Edward E. Jones, Victor A. Harris, The Attribution of Attitudes
In a 1971 experiment, a stranger handed people an unrequested can of Coke, then later asked them to buy raffle tickets. They bought roughly twice as many as people who'd gotten no …
— Dennis T. Regan, Effects of a Favor and Liking on Compliance
Plot people's most vivid life memories against the age they happened, and a bump appears between roughly age 10 and 30 — far more than recency alone explains. This 'reminiscence bu…
— David C. Rubin, Scott E. Wetzler, Robert D. Nebes, Autobiographical Memory Across the Adult Lifespan
In 1898, Norman Triplett timed children winding a fishing reel alone, then again next to a competitor. Almost every child sped up once a rival was present. His write-up is widely c…
— Norman Triplett, The Dynamogenic Factors in Pacemaking and Competition
In 1848, a blasting accident drove a metre-long iron rod through Phineas Gage's frontal lobe. He survived, still walking and talking within minutes, but friends said the once mild-…
— John Martyn Harlow, Passage of an Iron Rod through the Head
John Garcia found that rats given flavored water, then made nauseous by radiation hours later, avoided that flavor for life - despite no pain and a delay that broke every rule of s…
— John Garcia and Robert A. Koelling, Relation of Cue to Consequence in Avoidance Learning
Roger Brown and David McNeill gave students definitions of rare words and asked them to name the target. When stuck, people could reliably guess the first letter, syllable count, a…
— Roger Brown and David McNeill, The 'Tip of the Tongue' Phenomenon
In 1973, psychologist David Rosenhan and seven healthy volunteers faked a single symptom to get admitted to psychiatric hospitals, then acted completely normal afterward. Staff nev…
— David Rosenhan, On Being Sane in Insane Places
Researchers had men cross either a rickety suspension bridge or a solid, low one, then meet an attractive interviewer who left her number. Men from the scary bridge called back far…
— Donald Dutton and Arthur Aron, Some Evidence for Heightened Sexual Attraction Under Conditions of High Anxiety
In 1967, Stanley Milgram mailed folders to strangers in Nebraska and asked them to forward each one toward a specific stockbroker in Boston, passing it only to someone they knew pe…
— Stanley Milgram and Jeffrey Travers, An Experimental Study of the Small World Problem
A famous 1985 study found no evidence that basketball players who'd made recent shots were 'due' to keep scoring, and the 'hot hand fallacy' became textbook psychology. In 2018, ec…
— Joshua B. Miller and Adam Sanjurjo, Surprised by the Gambler's and Hot Hand Fallacies?
Baruch Fischhoff asked people to estimate the odds of different outcomes before Nixon's 1972 trip to China, then asked them again afterward to recall their original predictions. Pe…
— Baruch Fischhoff, Hindsight is not equal to foresight: The effect of outcome knowledge on judgment under uncertainty
Henri Tajfel randomly sorted participants into groups using trivial, meaningless criteria, even a coin toss. Despite knowing the grouping was arbitrary and having no history with t…
— Henri Tajfel, Experiments in Intergroup Discrimination
In a classic experiment, people judged whether a string of letters was a real word. They confirmed 'nurse' faster when it followed a related word like 'doctor' than when it followe…
— David Meyer and Roger Schvaneveldt, Facilitation in recognizing pairs of words: Evidence of a dependence between retrieval operations
In a city with 85% green cabs and 15% blue cabs, a witness who identifies cab colors correctly 80% of the time says a hit-and-run cab was blue. Most people guess it probably was bl…
— Amos Tversky and Daniel Kahneman, On prediction and judgment
The day after the Challenger shuttle disaster, psychologist Ulric Neisser had students write down exactly where they were when they heard the news. Resurveyed two and a half years …
— Ulric Neisser and Nicole Harsch, Phantom flashbulbs: False recollections of hearing the news about Challenger
In the Müller-Lyer illusion, a line capped with outward-pointing fins looks longer than an identical line capped with inward-pointing fins. It's one of psychology's oldest visual i…
— Franz Carl Müller-Lyer, Optische Urteilstäuschungen
Asked to rate how well they understand everyday devices, people rate themselves confidently — until asked to actually explain the mechanism step by step. Confidence drops sharply r…
— Leonid Rozenblit & Frank Keil, The Misunderstood Limits of Folk Science: An Illusion of Explanatory Depth
Patients with damage to the brain's primary visual cortex report seeing nothing in part of their vision, yet when forced to guess where an object is, they point to it far more ofte…
— Lawrence Weiskrantz, Blindsight: A Case Study and Implications
Amputees often feel their missing limb frozen in a painful position. Neuroscientist V. S. Ramachandran had patients place their remaining hand behind a mirror angled to create the …
— V. S. Ramachandran & Sandra Blakeslee, Phantoms in the Brain
In 1960, George Sperling flashed a grid of 12 letters for just 50 milliseconds. Asked to recall the whole grid, people could name only about a third of the letters. But cued to rep…
— George Sperling, The Information Available in Brief Visual Presentations
In the 1930s, Frederic Bartlett gave British readers an unfamiliar Native American folk tale and had them recall it again and again over weeks or months. Each retelling drifted fur…
— Frederic Bartlett, Remembering: A Study in Experimental and Social Psychology
Psychologist Gaetano Kanizsa arranged three wedge-cut circles so their gaps lined up like the corners of a triangle. Most viewers see a solid white triangle sitting on top, complet…
— Gaetano Kanizsa, Margini quasi-percettivi in campi con stimolazione omogenea
Surgeons removed both of Henry Molaison's hippocampi in 1953 to stop his severe seizures. He could still hold a thought for a few seconds and get better at physical tasks through p…
— William Beecher Scoville and Brenda Milner, Loss of Recent Memory after Bilateral Hippocampal Lesions
In the 1880s Hermann Ebbinghaus tested his own memory for nonsense syllables at intervals over days and plotted the results. Forgetting wasn't gradual and steady — it was steep at …
— Hermann Ebbinghaus, Über das Gedächtnis (Memory: A Contribution to Experimental Psychology)
In 1956, psychologist George Miller reviewed decades of experiments and found a strange coincidence: whether people were recalling digits, judging pitches, or naming colors, perfor…
— George A. Miller, The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information
In 1953, Colin Cherry played different messages into each ear of test subjects at once and found they could follow one and almost entirely ignore the other. His work named the 'coc…
— Colin Cherry, Some Experiments on the Recognition of Speech, with One and with Two Ears
Fergus Craik and Robert Lockhart's 1972 model overturned the idea that memory has fixed 'stores.' Instead, how deeply you process information determines how well you remember it: n…
— Fergus I. M. Craik and Robert S. Lockhart, Levels of Processing: A Framework for Memory Research
People consistently attribute their wins to their own ability and effort, but their losses to external circumstances beyond their control — a bad ref, an unfair test, the weather. …
— Edward E. Jones & Keith E. Davis; later Miller & Ross, Egotism in Attribution
Irving Janis coined 'groupthink' after studying disasters like the Bay of Pigs invasion, where Kennedy's advisors backed a plan several of them secretly thought was reckless. He fo…
— Irving Janis, Victims of Groupthink
In 1988, Samuelson and Zeckhauser found that when people are given a default option, they disproportionately keep it rather than choosing a genuinely better alternative — true for …
— William Samuelson & Richard Zeckhauser, Status Quo Bias in Decision Making
Psychologist Jack Brehm proposed in 1966 that when people feel a freedom is being threatened or taken away, they experience 'reactance' — a motivational push to reassert exactly th…
— Jack W. Brehm, A Theory of Psychological Reactance
In the 1960s, Roger Sperry and Michael Gazzaniga studied 'split-brain' patients whose corpus callosum had been cut to treat severe epilepsy. Flash a word to only the left eye and a…
— Roger W. Sperry, Some Functional Effects of Sectioning the Cerebral Commissures in Man
Prosopagnosia, or face blindness, leaves people unable to recognise faces — sometimes even their own in a mirror — despite normal vision and intelligence. Neurologist Oliver Sacks …
— Oliver Sacks, The Man Who Mistook His Wife for a Hat
Psychologist Mihaly Csikszentmihalyi interviewed painters, climbers and surgeons who described losing themselves completely in their work, and named it 'flow'. It shows up when a c…
— Mihaly Csikszentmihalyi, Flow: The Psychology of Optimal Experience
In Capgras delusion, first described by psychiatrist Joseph Capgras in 1923, a patient recognises a spouse's face perfectly but feels no emotional response to it — and concludes th…
— Joseph Capgras and Jean Reboul-Lachaux, L'illusion des sosies dans un délire systématisé chronique
Elliot Aronson had people listen to recordings of a quiz contestant — highly capable or merely average, and either flawless or fumbling a cup of coffee at the end. Listeners rated …
— Elliot Aronson, Ben Willerman & Joanne Floyd, The Effect of a Pratfall on Increased Interpersonal Attractiveness
Show people the same face in a group photo and alone, and they rate it as better-looking in the group. Researchers think the brain computes an average of nearby faces and each one …
— Drew Walker & Edward Vul, Why Faces Are and Are Not Special: An Effect of Attractiveness
A 19th-century neurologist electrically stimulated facial muscles and found genuine joy fires a muscle around the eyes that's hard to trigger on command. Fake smiles use the mouth …
— Guillaume Duchenne, Mécanisme de la Physionomie Humaine
Researchers recording a single neuron in a macaque's brain noticed it fired not only when the monkey grabbed a peanut, but also when it merely watched a researcher grab one. The ac…
— Giacomo Rizzolatti et al., Action recognition in the premotor cortex
In 1981, psychologist Ola Svenson asked American and Swedish students to rate their own driving skill and safety against the rest of the group. Roughly 90% of the US sample and mos…
— Ola Svenson, Are We All Less Risky and More Skillful Than Our Fellow Drivers?
In 1965, Robert Rosenthal and Lenore Jacobson gave elementary school teachers a list of students primed to show a sudden leap in ability that year — the names were picked entirely …
— Robert Rosenthal and Lenore Jacobson, Pygmalion in the Classroom
Marcel Proust described it first: a single bite of a tea-soaked madeleine flooded him with a childhood memory he hadn't consciously thought of in years. Psychologists now call this…
— Marcel Proust, In Search of Lost Time
Psychologist George Loewenstein described the 'hot-cold empathy gap': in a calm, 'cold' state, people consistently underestimate how much a 'hot' emotional or physical state — ange…
— George Loewenstein, Hot-Cold Empathy Gaps and Medical Decision Making
Working memory can only juggle so much at once, and every bit spent decoding a badly designed explanation is a bit that can't go toward actually learning. John Sweller found novice…
— John Sweller, Cognitive Load During Problem Solving: Effects on Learning
People consistently rate themselves as less biased than the average person, their own classmates, or strangers at an airport — even right after being taught exactly how a specific …
— Emily Pronin, Daniel Y. Lin, Lee Ross, The Bias Blind Spot: Perceptions of Bias in Self Versus Others
An availability cascade is a self-reinforcing loop: a claim gets attention, its repetition alone makes it feel more plausible, and public pressure to agree pulls in more repeaters.…
— Timur Kuran, Cass R. Sunstein, Availability Cascades and Risk Regulation
Stare at or repeat a word for about three minutes and it stops feeling like a word at all — just a strange sound. Psychologists Elizabeth Severance and Margaret Floy Washburn docum…
— Elizabeth Severance, Margaret Floy Washburn, The Loss of Associative Power in Words after Long Fixation
In the 1920s Bluma Zeigarnik noticed Berlin waiters could recall unpaid orders in vivid detail but forgot them the instant the bill was settled. Follow-up experiments found people …
— Bluma Zeigarnik, Zeigarnik effect
When someone else cuts you off in traffic, it's easy to assume they're simply reckless. When you do the same thing, you point to the emergency you're rushing to. Social psychologis…
— Lee Ross, The Intuitive Psychologist and His Shortcomings
In February 2015, a blurry photo of a striped dress went viral because people couldn't agree whether it was blue-and-black or white-and-gold. Vision scientists traced the split to …
— Pascal Wallisch, Illumination assumptions account for individual differences in the perceived colour of dress #TheDress
Contagious yawning shows up not only when you see someone yawn, but often just from reading about yawning, as you may be experiencing right now. Psychologist Robert Provine's exper…
— Robert Provine, Yawning
In the Sally-Anne test, a doll leaves her ball in a basket, then another doll secretly moves it while she's away. Children under four insist Sally will look in the new spot — they …
— Simon Baron-Cohen, Alan M. Leslie, and Uta Frith, Does the Autistic Child Have a "Theory of Mind"?
Classic memory experiments found people recall words far better when they generate them from a cue than when they simply read the completed pair, even with identical study time. Se…
— Norman J. Slamecka and Peter Graf, The Generation Effect: Delineation of a Phenomenon
Students who practiced math problems in shuffled order scored roughly double the students who drilled one problem type at a time, even though blocked practice felt easier in the mo…
— Kelli Taylor and Doug Rohrer, The Effects of Interleaved Practice
B.F. Skinner found that rewarding a behavior after an unpredictable number of tries produces the highest, steadiest response rate of any reinforcement schedule — and the one hardes…
— Charles B. Ferster and B.F. Skinner, Schedules of Reinforcement
In Mary Ainsworth's 'Strange Situation' procedure, a parent leaves and returns while researchers watch how the infant reacts. From this brief separation and reunion, Ainsworth iden…
— Mary Ainsworth, Mary Blehar, Everett Waters & Sally Wall, Patterns of Attachment: A Psychological Study of the Strange Situation
Jean Piaget showed young children two identical glasses of water, then poured one into a taller, thinner glass. Children under about seven typically insist the taller glass now hol…
— Jean Piaget, The Child's Conception of Number
The 'Jim twins' were separated as infants and reunited at 39, discovering they'd both become James — married twice, first to a Linda then a Betty, with sons named James Alan. They …
— Thomas J. Bouchard Jr., Minnesota Study of Twins Reared Apart
Ethologist Konrad Lorenz proposed that a cluster of infantile features — large eyes, a big head, chubby cheeks — automatically triggers nurturing behavior in adults. The 'kindchens…
— Konrad Lorenz, Die angeborenen Formen möglicher Erfahrung
In 1874, neurologist Carl Wernicke described stroke patients who spoke in smooth, grammatical sentences that carried almost no meaning — fluent jargon. Unlike Broca's patients, the…
— Carl Wernicke, Der aphasische Symptomencomplex
In grapheme-color synesthesia, letters and numbers trigger an automatic, consistent color perception — a 3 might always look red, a 7 always green. It isn't imagination: brain scan…
— Richard E. Cytowic, The Man Who Tasted Shapes
Kim Peek could reportedly scan a left-hand and right-hand page simultaneously, one eye tracking each, and recall the contents of thousands of books years later. He had savant syndr…
— Darold A. Treffert, Extraordinary People: Understanding Savant Syndrome
William James and Carl Lange independently proposed, in the 1880s, that emotion isn't what causes a bodily reaction — it's the reverse. See a bear, your body reacts first (racing h…
— William James, What is an Emotion?
Across ages, cultures and income levels, people systematically overestimate their odds of good outcomes (a long marriage, career success) and underestimate their odds of bad ones (…
— Tali Sharot, The Optimism Bias: A Tour of the Irrationally Positive Brain
Researchers tested different hotel card messages asking guests to reuse towels. Appeals to protecting the environment barely moved behavior, but a card stating that most previous g…
— Noah J. Goldstein, Robert B. Cialdini, Vladas Griskevicius, A Room with a Viewpoint: Using Social Norms to Motivate Environmental Conservation in Hotels
Adults can recall almost nothing about their first few years of life, a gap known as childhood amnesia. It isn't that nothing happened — infants do form memories — but the hippocam…
— JoNell A. Usher, Ulric Neisser, Childhood Amnesia and the Beginnings of Memory for Four Early Life Events
In 1946, Solomon Asch read people identical lists of personality traits, only reversing the order. Describing someone as "intelligent, industrious, impulsive, critical, stubborn, e…
— Solomon E. Asch, Forming Impressions of Personality
In Carl Hovland's Yale persuasion studies, people who heard a claim from a low-credibility source discounted it at first. Weeks later they'd forgotten who said it but still remembe…
— Carl Hovland and Walter Weiss, The Influence of Source Credibility on Communication Effectiveness
The Implicit Association Test measures how quickly you pair words and faces with 'good' or 'bad' categories. People consistently respond faster when the pairing matches a familiar …
— Anthony Greenwald, Debbie McGhee, Jordan Schwartz, Measuring Individual Differences in Implicit Cognition: The Implicit Association Test
When two things are both statistically uncommon, seeing them paired even a few times makes the pairing stand out in memory, so you overestimate how often they actually go together.…
— David L. Hamilton, Robert K. Gifford, Illusory Correlation in Interpersonal Perception: A Cognitive Basis of Stereotypic Judgments
Petty and Cacioppo's model says people process persuasive messages one of two ways. On the 'central route' they weigh the actual arguments, producing attitudes that last and resist…
— Richard E. Petty, John T. Cacioppo, Communication and Persuasion: Central and Peripheral Routes to Attitude Change
Hide a person's real hand from view, place a rubber hand where they can see it, and stroke both in perfect sync. Within minutes most people report feeling the touch as coming from …
— Matthew Botvinick and Jonathan Cohen, Rubber hands 'feel' touch that eyes see
In the 1910s-20s, Soviet filmmaker Lev Kuleshov spliced one identical shot of an actor's neutral face together with a bowl of soup, a girl in a coffin, and a woman on a divan. Audi…
— Vsevolod Pudovkin, Film Technique and Film Acting
Flash a fast sequence of letters or images, roughly ten per second, with two targets hidden inside. People reliably catch the first one, but if the second target appears within abo…
— Jane Raymond, Kimron Shapiro, and Karen Arnell, Temporary suppression of visual processing in an RSVP task: An attentional blink?
Show someone a mediocre apartment right after a terrible one, and it suddenly looks great; show the identical apartment after a fantastic one, and it looks disappointing. Nothing a…
— Harry Helson, Adaptation-Level Theory: An Experimental and Systematic Approach to Behavior
Ask people how confident they are in an answer, and their stated certainty routinely outruns how often they're actually right. In classic calibration studies, people who said they …
— Baruch Fischhoff, Paul Slovic, Sarah Lichtenstein, Knowing with Certainty: The Appropriateness of Extreme Confidence Judgments
Petter Johansson and colleagues showed participants two faces and asked them to point to the more attractive one, then handed over that photo using a sleight-of-hand card trick tha…
— Petter Johansson, Lars Hall, Betty Sikström, Andreas Olsson, Failure to Detect Mismatches Between Intention and Outcome in a Simple Decision Task
Edward Deci and Richard Ryan's self-determination theory argues that lasting motivation depends on three needs being met: autonomy, competence, and relatedness. External rewards th…
— Edward L. Deci, Richard M. Ryan, Intrinsic Motivation and Self-Determination in Human Behavior
Danish psychologist Edgar Rubin's 1915 vase illusion showed that perception constantly assigns regions of a scene to 'figure' (the object you're looking at) or 'ground' (the backgr…
— Edgar Rubin, Visuell wahrgenommene Figuren
Cotard delusion is a rare psychiatric condition in which patients deny parts of their own body, mind, or existence, sometimes insisting they are dead, rotting, or made of nothing. …
— Jules Cotard, Du délire des négations
After certain strokes or split-brain surgery, one hand can perform purposeful actions, unbuttoning a shirt the other hand just buttoned, grabbing objects, even reaching for a partn…
— Serge Brion and Claude-Paul Jedynak (named the syndrome), Alien hand syndrome
During a six-day bank robbery and hostage siege at Norrmalmstorg in Stockholm in August 1973, the hostages resisted rescue and later publicly defended their captors. Criminologist …
— Nils Bejerot, Stockholm syndrome
The clustering illusion is the tendency to see meaningful clusters in what's actually random noise, like wartime Londoners convinced German V-1 rockets were targeting specific neig…
— Thomas Gilovich, How We Know What Isn't So
Even when which ear a sound comes from is completely irrelevant to the task, people respond faster and more accurately when their answer button is on the same side as the sound. J.…
— J. R. Simon and A. P. Rudell, Auditory S-R Compatibility: The Effect of an Irrelevant Cue on Information Processing
People who repeatedly ride a moving platform, then step onto the same platform stationary, stumble and wobble even though they know full well it isn't moving. Raymond Reynolds and …
— Raymond F. Reynolds and Adolfo M. Bronstein, The Broken Escalator Phenomenon
Shown the same photo and told a man is named 'Mr Baker,' people forget it quickly; told instead that his job is 'baker,' they remember far better — even though the word is identica…
— Gillian Cohen, Why Is It Difficult to Put Names to Faces?
Robert Stickgold's 2000 study had people play Tetris for hours across three days, then tracked what they saw drifting through their minds at sleep onset — most reported vivid, intr…
— Robert Stickgold et al., Replaying the Game: Hypnagogic Images in Normals and Amnesics
Gamblers watched black come up again and again and grew certain red was 'due,' piling money onto red as the streak grew. Every spin was independent of the last, so the odds of red …
— Amos Tversky and Daniel Kahneman (naming); Monte Carlo Casino incident, 1913, Gambler's fallacy
Elizabeth Newton had 'tappers' drum out well-known songs on a tabletop while 'listeners' tried to name the tune. Tappers predicted listeners would succeed half the time; the real r…
— Elizabeth Newton, Overconfidence in the Communication of Intent
In a 2002 trial, surgeons gave some osteoarthritis patients real arthroscopic knee surgery and others only matching skin incisions with no procedure performed at all. Two years lat…
— J. Bruce Moseley et al., A Controlled Trial of Arthroscopic Surgery for Osteoarthritis of the Knee
Elizabeth Loftus and Jacqueline Pickrell told adults four childhood stories supplied by a relative — three true, one entirely invented, about getting lost in a mall at age five. Ab…
— Elizabeth Loftus and Jacqueline Pickrell, The Formation of False Memories
Watching preschoolers with their parents, Diana Baumrind found that kids of warm-but-firm 'authoritative' parents were more capable and confident than kids of strict 'authoritarian…
— Diana Baumrind, Child Care Practices Anteceding Three Patterns of Preschool Behavior
Lev Vygotsky argued that learning happens best not at what a child can already do alone, nor at what's far beyond them, but in between, tasks they can finish only with a bit of gui…
— Lev Vygotsky, Mind in Society: The Development of Higher Psychological Processes
Lawrence Kohlberg asked children whether a man should steal an overpriced drug to save his dying wife, then studied not their answer but their reasoning. He found moral reasoning u…
— Lawrence Kohlberg, The Development of Modes of Moral Thinking and Choice in the Years 10 to 16
Wolfgang Kohler gave chimpanzees a banana just out of reach, with sticks and crates scattered around the cage. Instead of blind trial and error, the chimps would pause, then sudden…
— Wolfgang Kohler, The Mentality of Apes
In 1953, Eugene Aserinsky attached electrodes to his 8-year-old son and noticed the boy's eyes darting beneath closed lids at regular intervals through the night. He and his superv…
— Eugene Aserinsky and Nathaniel Kleitman, Regularly Occurring Periods of Eye Motility, and Concomitant Phenomena, During Sleep
Psychologist Peter Thompson rotated Margaret Thatcher's eyes and mouth 180 degrees within an otherwise normal photo of her face, and the result looked monstrous — but only right-si…
— Peter Thompson, Margaret Thatcher: A New Illusion
Anton–Babinski syndrome strikes people who've lost their sight to damage in the brain's visual cortex, not the eyes. Told they're blind, patients confidently deny it and confabulat…
— Gabriel Anton and Joseph Babinski, Anton–Babinski syndrome
Erik Erikson proposed that personality develops through eight life stages, each centered on its own conflict — trust versus mistrust in infancy, identity versus role confusion in a…
— Erik Erikson, Childhood and Society
Researchers gave people false feedback on a task, then fully explained the feedback had been randomly assigned and meant nothing. People's opinions of their own ability barely move…
— Lee Ross, Mark Lepper & Michael Hubbard, Perseverance in Self-Perception and Social Perception: Biased Attributional Processes in the Debriefing Paradigm
Decades of factor-analysis on personality descriptions across languages and cultures kept collapsing into the same five dimensions: openness, conscientiousness, extraversion, agree…
— Ernest Tupes & Raymond Christal; popularized by Lewis Goldberg, Robert McCrae & Paul Costa, The Big Five personality traits (OCEAN model)
Offer people a small item and a large one and choices split fairly evenly. Add a middling option priced almost the same as the large — one nobody actually picks — and most people s…
— Joel Huber, John Payne & Christopher Puto, Adding Asymmetrically Dominated Alternatives: Violations of Regularity and the Similarity Hypothesis
Psychiatrist Viktor Frankl, drawing on his years in Nazi concentration camps, observed that prisoners who held onto some purpose — a person to return to, a task left unfinished — w…
— Viktor E. Frankl, Man's Search for Meaning
In a 2011 study, people who expected to have later access to a fact remembered it far worse than those who thought it would be erased — but they got much better at remembering wher…
— Betsy Sparrow, Jenny Liu & Daniel M. Wegner, Google Effects on Memory: Cognitive Consequences of Having Information at Our Fingertips
In the early 1960s, Aaron Beck kept hearing depressed patients voice automatic thoughts — 'I'm worthless,' 'this will fail' — that didn't hold up against the evidence. Rather than …
— Aaron T. Beck, Cognitive behavioral therapy
In 1987, Cindy Hazan and Phillip Shaver asked adults to pick which of three short descriptions best matched how they felt in romantic relationships — and found the same secure, anx…
— Cindy Hazan & Phillip Shaver, Romantic Love Conceptualized as an Attachment Process
In 1954, Gordon Allport proposed that contact between groups reduces prejudice — but only when both sides have equal status, share a common goal, cooperate rather than compete, and…
— Gordon W. Allport, The Nature of Prejudice
Tanya Chartrand and John Bargh had participants chat with a partner (actually a researcher) who deliberately rubbed their face or shook their foot during the conversation. Particip…
— Tanya L. Chartrand, John A. Bargh, The Chameleon Effect: The Perception-Behavior Link and Social Interaction
Daryl Bem argued that people often don't have direct access to their own attitudes, so they infer them the same way an outside observer would: by watching their own behavior. Smile…
— Daryl J. Bem, Self-Perception Theory
Leon Festinger proposed that people have a built-in drive to evaluate their own opinions and abilities, and when no objective yardstick exists, they measure themselves against othe…
— Leon Festinger, A Theory of Social Comparison Processes
People recall information more readily when their current mood matches the emotional tone of the memory — sad people retrieve sad memories faster, and cheerful people retrieve chee…
— Gordon H. Bower, Mood and Memory
At a 1906 country fair, statistician Francis Galton collected 787 guesses of an ox's dressed weight from a crowd of butchers, farmers and passersby. No individual guess came close,…
— Francis Galton, Vox Populi
In Werner Guth's 1982 ultimatum game, one player proposes how to split a sum of money and the other can accept or reject it — rejecting means both walk away with nothing. A purely …
— Werner Guth, Rolf Schmittberger & Bernd Schwarze, An Experimental Analysis of Ultimatum Bargaining
In a 1998 study, people who had just told a lie guessed that far more observers could tell they were lying than actually could, and people forced to taste something disgusting beli…
— Thomas Gilovich, Kenneth Savitsky & Victoria Husted Medvec, The Illusion of Transparency: Biased Assessments of Others' Ability to Read One's Emotional States
In 1969, Serge Moscovici and Marisa Zavalloni had French students discuss their attitudes toward their president and toward Americans, then compared opinions before and after. Disc…
— Serge Moscovici & Marisa Zavalloni, The Group as a Polarizer of Attitudes
Economist Thomas Schelling observed that a story about one specific, named person in danger provokes far more concern, donations and action than statistics about thousands facing t…
— Thomas Schelling, Identifiable Victim Effect
Moral licensing describes how a recent act of virtue can quietly loosen someone's ethical guardrails: in one study, people who'd just picked a woman or a Black candidate for a hypo…
— Wikipedia contributors, Self-Licensing
Shown a description of 'Linda' as a bright, outspoken philosophy graduate concerned with social justice, most people asked to rank likely careers rate 'bank teller and active in th…
— Amos Tversky & Daniel Kahneman, Representativeness Heuristic
Economists Dan Galai and Orly Sade named the ostrich effect for the tendency to avoid useful information specifically because it might be bad news — investors log into their accoun…
— Dan Galai & Orly Sade, Ostrich Effect
In 1959, Festinger and Carlsmith had participants tell a waiting 'subject' that a tedious task was fascinating, paying some $1 and others $20 to do it. The $1 liars later rated the…
— Leon Festinger and James M. Carlsmith, Cognitive Consequences of Forced Compliance
Jean Piaget found that infants younger than about eight months won't search for an object the moment it's hidden from view, as if out of sight truly means out of mind. The capacity…
— Jean Piaget, The Construction of Reality in the Child
Edward Tolman let rats explore a maze for days with no food waiting at the end, and their performance barely improved. The moment he added a reward, they suddenly ran it almost as …
— Edward C. Tolman and C. H. Honzik, Introduction and Removal of Reward, and Maze Performance in Rats
Faced with a runaway trolley, most people say it's fine to flip a switch that diverts it onto a track where it kills one person instead of five. Given the exact same math, but fram…
— Joshua D. Greene et al., An fMRI Investigation of Emotional Engagement in Moral Judgment
In the Nun Study, David Snowdon analyzed autobiographies 678 nuns wrote in their early twenties, decades before any sign of dementia. Essays low in 'idea density' — fewer distinct …
— David Snowdon, Aging with Grace
Psychologist James Gross found that people who consciously reinterpret an upsetting situation ('reappraisal') feel less distress and show calmer physiological responses than people…
— James J. Gross, Antecedent- and Response-Focused Emotion Regulation
Barbara Fredrickson's broaden-and-build theory found that positive emotions like joy and curiosity briefly expand the range of thoughts and actions people consider, while negative …
— Barbara Fredrickson, The Broaden-and-Build Theory of Positive Emotions
In a 1950 study of a postwar student housing complex, Festinger, Schachter and Back mapped friendships and found physical distance mattered more than shared interests: people two d…
— Leon Festinger, Stanley Schachter, Kurt Back, Social Pressures in Informal Groups
Abraham Maslow proposed that people pursue needs in a rough order: physiological survival, safety, belonging, esteem, and finally self-actualisation, the drive to fulfil your own p…
— Abraham Maslow, A Theory of Human Motivation
In 1979, psychologist Robert Rosenthal named the 'file drawer problem': studies that fail to find an effect are far less likely to be submitted or accepted for publication than one…
— Robert Rosenthal, The File Drawer Problem and Tolerance for Null Results
In 1944, Fritz Heider and Marianne Simmel showed people a 90-second animation of two triangles and a circle moving around a rectangle, with no faces, sounds or plot. Almost everyon…
— Fritz Heider and Marianne Simmel, An Experimental Study of Apparent Behavior
Psychologist Daniel Wegner noticed that long-term couples quietly split up their memory the way they split up chores: one partner becomes the household's expert on finances, the ot…
— Daniel Wegner, Transactive Memory: A Contemporary Analysis of the Group Mind
Wilhelm Wundt opened the first laboratory built specifically to study the mind experimentally, treating reaction times and sensations as measurable data rather than philosophy. He …
— Wilhelm Wundt, Wilhelm Wundt
In a classic experiment, shoppers picked a 'best' pair from four identical stockings, and most chose the rightmost one — a known position bias. Asked why, almost no one mentioned p…
— Richard E. Nisbett and Timothy D. Wilson, Telling More Than We Can Know: Verbal Reports on Mental Processes
David Premack showed reinforcement isn't some fixed list of treats — it's relative. Any behavior you perform often can reinforce any behavior you perform rarely, whichever two beha…
— David Premack, Toward Empirical Behavior Laws: I. Positive Reinforcement
Shown pairs of 3D block shapes and asked if they were the same object just turned, or mirror images, people's reaction time rose in a straight line with the angle of rotation betwe…
— Roger N. Shepard and Jacqueline Metzler, Mental Rotation of Three-Dimensional Objects
Ask most people to picture an apple and they see one. People with aphantasia report nothing — no image forms when they try to visualize. Neurologist Adam Zeman named the condition …
— Adam Zeman, Michaela Dewar & Sergio Della Sala, Lives without imagery – Congenital aphantasia
Look at red-and-black stripes then green-and-black stripes for a few minutes, and afterward black-and-white stripes will show faint tinges of the opposite colors — but only at that…
— Celeste McCollough, Color Adaptation of Edge-Detectors in the Human Visual System
Some people who lose much of their vision to conditions like macular degeneration start seeing detailed, vivid hallucinations — patterns, faces, entire scenes — despite knowing non…
— Charles Bonnet; named by Georges de Morsier, Charles Bonnet syndrome
Roughly two-thirds of people report the eerie sense of having lived a moment before. Researcher Anne Cleary has recreated déjà vu in the lab using virtual scenes with familiar spat…
— Anne M. Cleary; Chris J. A. Moulin, Déjà vu
Julian Rotter proposed that people sit somewhere on a spectrum between an 'internal' locus of control, believing they steer their own outcomes, and an 'external' one, crediting fat…
— Julian B. Rotter, Generalized Expectancies for Internal Versus External Control of Reinforcement
Donald Hebb proposed that when one neuron repeatedly helps fire another, the connection between them physically strengthens over time. It was a theoretical postulate in a psycholog…
— Donald O. Hebb, The Organization of Behavior
Edward Thorndike put hungry cats in boxes they could only escape by pulling a loop or lever. Their escape times fell over repeated trials not through sudden insight but blind trial…
— Edward L. Thorndike, Animal Intelligence: An Experimental Study of the Associative Processes in Animals
Konrad Lorenz found that newly hatched geese bond to the first moving thing they see during a brief critical window, real mother or not. When he made sure he was that first sight, …
— Konrad Lorenz, King Solomon's Ring
In 1974 Alan Baddeley and Graham Hitch replaced the idea of a single short-term memory store with a model built from separate parts: an inner voice for sounds and words, an inner e…
— Alan Baddeley and Graham Hitch, Working Memory (in The Psychology of Learning and Motivation, Vol. 8)
Neuroscientist Eleanor Maguire scanned London taxi drivers who had spent years memorising the city's 25,000 streets and found their posterior hippocampus, a brain region tied to sp…
— Eleanor Maguire et al., Navigation-Related Structural Change in the Hippocampi of Taxi Drivers
In the Iowa Gambling Task, players draw cards from four decks, some far riskier than others. Patients with damage to the ventromedial prefrontal cortex kept drawing from the bad de…
— Antoine Bechara, Antonio Damasio, Hanna Damasio, Daniel Tranel, Insensitivity to Future Consequences Following Damage to Human Prefrontal Cortex
Developed from WWII radar operators trying to spot enemy blips in noise, signal detection theory showed that any yes/no judgement combines two separate things: how well you can act…
— David Green and John Swets, Signal Detection Theory and Psychophysics
When a Chicago group predicted the world would end and it didn't, psychologist Leon Festinger had infiltrated them to watch what happened next. Instead of admitting error, members …
— Leon Festinger, Henry Riecken, and Stanley Schachter, When Prophecy Fails
In 1958, Jean Berko Gleason showed preschoolers a made-up creature labeled a 'wug,' then a second one, and asked them to finish: 'Now there are two ___.' Children who had never hea…
— Jean Berko Gleason, The Child's Learning of English Morphology
In 1861, surgeon Paul Broca examined a patient who understood language but could only say the syllable 'tan.' An autopsy after his death found damage concentrated in one region of …
— Paul Broca, Remarks on the Seat of the Faculty of Articulated Language
B.F. Skinner built a chamber where an animal's own actions -- pressing a lever, pecking a disk -- triggered food, and recorded exactly how reward schedules changed behavior. The 'S…
— B.F. Skinner, The Behavior of Organisms
Sheena Iyengar and Mark Lepper set up tasting booths offering either 6 or 24 flavors of jam. The bigger display drew more browsers, but only 3% of them bought a jar — versus 30% at…
— Sheena Iyengar, Mark Lepper, When Choice is Demotivating: Can One Desire Too Much of a Good Thing?
Tversky and Kahneman told people 600 lives were at risk from a disease and offered two identical programs, one phrased as lives saved and one as lives lost. When framed as '200 peo…
— Amos Tversky, Daniel Kahneman, The Framing of Decisions and the Psychology of Choice
Robert Cialdini's scarcity principle holds that things become more desirable the moment they seem limited or about to disappear, largely out of fear of missing out rather than the …
— Robert Cialdini, Influence: The Psychology of Persuasion
Paul Slovic proposed that people often judge risks and benefits not by weighing evidence, but by consulting a fast emotional tag attached to the idea itself: things that feel good …
— Paul Slovic, Melissa Finucane, Ellen Peters, Donald G. MacGregor, The Affect Heuristic
Francis Galton found that unusually tall parents tend to have somewhat shorter children, and unusually short parents somewhat taller ones — not because of any active correction, bu…
— Francis Galton, Regression Towards Mediocrity in Hereditary Stature
Surveying college students, researchers found most of them were personally uncomfortable with how much drinking happened on campus — but each one believed everyone else was fine wi…
— Deborah Prentice and Dale Miller, Pluralistic Ignorance and Alcohol Use on Campus: Some Consequences of Misperceiving the Social Norm
Naive realism is the quiet assumption that your own perception of a situation is simply objective reality, unfiltered by any personal slant. It follows that anyone who sees things …
— Lee Ross and Andrew Ward, Naive Realism in Everyday Life: Implications for Social Conflict and Misunderstanding
The nocebo effect is the evil twin of the placebo effect: telling someone a harmless treatment might cause side effects makes some of them genuinely feel those side effects, with m…
— Walter Kennedy, The Nocebo Reaction
In a classic experiment, people spun a rigged wheel that landed on either 10 or 65, then guessed what percentage of UN countries were African. Those who saw 65 guessed far higher t…
— Amos Tversky and Daniel Kahneman, Judgment under Uncertainty: Heuristics and Biases
Martin Seligman and Steven Maier gave dogs mild shocks they had no way to stop, then later put them in a box where jumping over a low barrier would end the shock. The dogs that had…
— Martin E. P. Seligman and Steven F. Maier, Failure to Escape Traumatic Shock
Henry Roediger and Jeffrey Karpicke had students study a passage, then either re-read it repeatedly or try to recall it from memory. A week later, the students who had quizzed them…
— Henry L. Roediger III and Jeffrey D. Karpicke, The Power of Testing Memory: Basic Research and Implications for Educational Practice
Harry Harlow raised infant rhesus monkeys with two artificial mothers: a bare wire frame that dispensed milk, and a soft cloth-covered frame that dispensed nothing. The infants fed…
— Harry F. Harlow, The Nature of Love
Angela Duckworth measured 'grit' — sustained passion and perseverance toward long-term goals — with a short questionnaire. It out-predicted IQ, SAT scores and physical fitness for …
— Angela Duckworth, Grit: The Power of Passion and Perseverance
Eleanor Rosch found mental categories aren't defined by strict rules but by how closely something matches a prototype. People rate a robin as a better example of 'bird' than a peng…
— Eleanor Rosch, Cognitive Representations of Semantic Categories
Shown one spiky shape and one blobby shape, people overwhelmingly call the spiky one 'kiki' and the round one 'bouba' — a pattern that holds across languages, alphabets, and even i…
— Vilayanur S. Ramachandran, Edward M. Hubbard, Synaesthesia — A Window Into Perception, Thought and Language
Benjamin Libet asked people to flick their wrist whenever they felt like it, while recording their brain activity and the exact moment they felt the urge to move. A measurable spik…
— Benjamin Libet, Curtis A. Gleason, Elwood W. Wright, Dennis K. Pearl, Time of Conscious Intention to Act in Relation to Onset of Cerebral Activity (Readiness-Potential)
In 1980, Michael Posner had people fix their gaze on a center point while an arrow briefly flashed left or right, then respond to a target that popped up on one side. Correctly-cue…
— Michael I. Posner, Orienting of Attention
In 1904, Charles Spearman noticed that people's scores across wildly different mental tests, math, vocabulary, spatial reasoning, were almost always positively correlated. He inven…
— Charles Spearman, "General Intelligence," Objectively Determined and Measured
In 1923, Max Wertheimer catalogued the rules your visual system uses to bundle raw fragments into objects: things close together, similar in shape or color, or moving in unison get…
— Max Wertheimer, Laws of Organization in Perceptual Forms
In a widely cited 1995 review, Roy Baumeister and Mark Leary argued that forming and keeping lasting social bonds is a fundamental human motivation, not a byproduct of other needs.…
— Roy F. Baumeister and Mark R. Leary, The Need to Belong: Desire for Interpersonal Attachments as a Fundamental Human Motivation
Leon Kamin trained rats until a tone reliably predicted a shock, then added a light alongside that same tone-shock pairing. Tested alone, the light produced almost no fear response…
— Leon J. Kamin, "Attention-like" Processes in Classical Conditioning, in Miami Symposium on the Prediction of Behavior: Aversive Stimulation
In Edward Tronick's Still Face Paradigm, a mother plays normally with her infant, then suddenly holds a silent, expressionless face for a few minutes. The baby tries everything — s…
— Edward Tronick, Heidelise Als, Lauren Adamson, Susan Wise, T. Berry Brazelton, The Infant's Response to Entrapment Between Contradictory Messages in Face-to-Face Interaction
Morton Deutsch and Harold Gerard reran Asch's line experiment with a twist: sometimes subjects answered privately and anonymously. People still conformed even when no one could jud…
— Morton Deutsch and Harold B. Gerard, A Study of Normative and Informational Social Influences Upon Individual Judgment
In 1966, Elaine Walster (later Hatfield) randomly paired 752 students for a blind computer dance, expecting people to prefer partners who matched their own rated attractiveness. In…
— Elaine Walster, Vera Aronson, Darcy Abrahams, Leon Rottmann, Importance of Physical Attractiveness in Dating Behavior
Ivan Pavlov noticed his lab dogs drooled at the mere footsteps of the assistant who fed them, not just at the food itself. By repeatedly pairing a neutral sound with feeding, he sh…
— Ivan Pavlov, Conditioned Reflexes
People report vivid, detailed memories of shocking news, where they were, who told them, and feel unusually confident those memories are accurate. Follow-up studies that tracked pe…
— Roger Brown and James Kulik, Flashbulb Memories
Where the optic nerve exits each eye there are no light receptors at all, a literal blind spot in your visual field. You never notice it because your brain fills the gap with a pla…
— Edme Mariotte, Blind spot (vision)
Allan Paivio's dual-coding theory found information encoded both verbally and visually gets stored through two separate memory pathways instead of one, making it easier to retrieve…
— Allan Paivio, Imagery and Verbal Processes
In 1978, psychologists Pauline Clance and Suzanne Imes described the 'impostor phenomenon': despite real credentials, awards, and praise, the high-achieving women they studied felt…
— Pauline Rose Clance and Suzanne Imes, The Imposter Phenomenon in High Achieving Women: Dynamics and Therapeutic Intervention
In the late 1960s, psychologist Paul Ekman showed photos of faces to the Fore people of Papua New Guinea, who had almost no contact with the outside world. They matched expressions…
— Paul Ekman and Wallace V. Friesen, Constants Across Cultures in the Face and Emotion
In 1977, psychologist Albert Bandura proposed that self-efficacy — your belief in your own ability to pull off a specific task — shapes which challenges you attempt, how much effor…
— Albert Bandura, Self-Efficacy: Toward a Unifying Theory of Behavioral Change
In 1993, Clemens Kirschbaum and colleagues designed the Trier Social Stress Test: give someone a few minutes to prepare a speech, then have them deliver it to a stone-faced panel a…
— Clemens Kirschbaum, Karl-Martin Pirke and Dirk H. Hellhammer, The 'Trier Social Stress Test' — A Tool for Investigating Psychobiological Stress Responses in a Laboratory Setting
Psychologists built a table with a checkerboard pattern under glass — flush on one side, dropped several feet on the other, creating the illusion of a sudden ledge. Most six-to-fou…
— Eleanor J. Gibson & Richard D. Walk, The 'Visual Cliff'
Cialdini and colleagues asked students to join a 7 a.m. study, either naming the time upfront or only after they'd already agreed to take part. Revealing the costly detail after co…
— Robert B. Cialdini, John T. Cacioppo, Rosemary Bassett & John A. Miller, Low-Ball Procedure for Producing Compliance: Commitment then Cost
Jozef Nuttin noticed he preferred license plates containing letters from his own name, then tested it systematically. Across dozens of studies in over a dozen countries and four al…
— Jozef M. Nuttin Jr., Narcissism Beyond Gestalt and Awareness: The Name Letter Effect
In 1970, researchers hired an actor to deliver an entirely made-up, jargon-filled lecture on a topic he knew nothing about, coached only to be warm, confident and expressive. Exper…
— Donald H. Naftulin, John E. Ware Jr. & Frank A. Donnelly, The Doctor Fox Lecture: A Paradigm of Educational Seduction
Finnish sociologist Edward Westermarck proposed in 1891 that close physical proximity during the first few years of life suppresses later sexual attraction, an evolved mechanism to…
— Edward Westermarck, The History of Human Marriage
In a 1995 study, Claude Steele and Joshua Aronson found Black students performed significantly worse on a verbal test when it was framed as diagnostic of intellectual ability, comp…
— Claude M. Steele, Joshua Aronson, Stereotype Threat and the Intellectual Test Performance of African Americans
In a 1978 study, Steven Berglas and Edward Jones found that after succeeding on a test through luck rather than skill, many participants chose to take a performance-impairing drug …
— Steven Berglas, Edward E. Jones, Drug Choice as a Self-Handicapping Strategy in Response to Noncontingent Success
In a 2007 study, Doug Rohrer and Kelly Taylor had students practice math problems either grouped by type, all of one kind before moving to the next, or interleaved, with types mixe…
— Doug Rohrer, Kelly Taylor, The Shuffling of Mathematics Problems Improves Learning
In a 1975 study, divers memorized word lists either on a beach or fully submerged underwater, then recalled them in either the same or the opposite setting. Recall was consistently…
— Duncan Godden and Alan Baddeley, Context-dependent memory in two natural environments: on land and underwater
In a 1973 experiment, participants viewed 10,000 photographs for a few seconds each, then were tested on recognizing them against new images days afterward, with accuracy staying a…
— Lionel Standing, Learning 10,000 pictures
In a 1977 experiment, people recalled far more adjectives when asked "does this describe you?" than when asked to judge the same words for spelling, sound, or even general meaning.…
— Timothy Rogers, Nicholas Kuiper, and William Kirker, Self-reference and the encoding of personal information
In a 1974 field experiment, men who had just crossed a swaying, high suspension bridge rated a female interviewer as more attractive and were more likely to call her later than men…
— Donald Dutton and Arthur Aron, Some evidence for heightened sexual attraction under conditions of high anxiety