Psychology

130 cards about Psychology, with explanations, methods and source links.

Cards about Psychology

• Why is it so hard to say what color a word is printed in?

  Take the word "blue", print it in red ink, and say the ink color out loud. Nothing about that is difficult, and most people still slow down, stumble and get it wrong. Why does an easy task fight back?

  Source: Journal of Experimental Psychology, Stroop 1935

• Why did the people who paid full price show up to more plays?

  Hal Arkes and Catherine Blumer stopped people buying season tickets to a theater series and sorted them at random into three groups: full price, small discount, large discount. The discount came out of a draw and reflected nothing about the plays. Who came to more of them?

  Source: Arkes and Blumer, Organizational Behavior and Human Decision Processes

• What happened when the Dunning-Kruger effect was run on random data?

  The Dunning-Kruger effect, as the 1999 paper put it, is that poor performers rate themselves too highly, because the knowledge they lack is the same knowledge that would let them see it. The chart behind it is persuasive. Then someone fed the same method data with nothing in it at all. What came out?

  Source: Gignac and Zajenkowski, Intelligence

• Would you notice if the person you were talking to was swapped for someone else?

  Everyone is certain they would notice. To test it, researchers stopped passers-by on a campus to ask directions, and mid-conversation two workmen carried a door between the two of them and swapped the questioner for an entirely different person. How many noticed?

  Source: Simons & Levin, Psychonomic Bulletin & Review

• How can anyone miss a gorilla walking through the middle of the screen?

  Participants watched a video of two teams passing balls and were asked to count the passes of one team only. Halfway through, a person in a gorilla suit walked between the players, stopped for a moment, and went on. How many reported seeing it?

  Source: Simons & Chabris, Perception

• How does one word in a question plant a memory of something that never happened?

  Elizabeth Loftus showed participants a film of a car accident, then asked some of them how fast the cars were going when they hit each other, and the others when they smashed into each other. A week later all of them were asked whether they had seen broken glass. There was no broken glass in the film at all. What did they answer?

  Source: Loftus & Palmer, Journal of Verbal Learning and Verbal Behavior

• What was left of the marshmallow test when they ran it on ten times as many children?

  In the marshmallow test a four-year-old is left alone with a sweet and promised two for waiting. Years later the ones who managed to wait apparently did better in life, and that became a story about delayed gratification and willpower. In 2018 researchers ran it again on a large, representative sample. What survived?

  Source: Watts, Duncan & Quan, Psychological Science

• Why do we remember a long experience by only two moments of it?

  Participants went through a short, unpleasant spell with a hand in cold water, and alongside it a longer spell containing exactly the same cold plus an extra stretch in water that had warmed a little. Then they were asked which one they would rather repeat. What did they choose?

  Source: Kahneman et al., Psychological Science

• How do you get a brain to adopt a rubber hand as its own?

  A brain is supposed to know where your hand is, which is about as basic as a sensation gets. In the experiment a real hand is hidden, a rubber hand is laid where it would be, and brushes are drawn across both at exactly the same moment. What happens then?

  Source: Botvinick & Cohen, Nature

• What does the familiar version of the Milgram experiment leave out?

  In the Milgram experiment of 1961, participants were asked to deliver what they believed were rising electric shocks to another person, on the instructions of a researcher with authority. The result has been quoted ever since as a single number summing up human nature. What is that number hiding?

  Source: Milgram, Journal of Abnormal and Social Psychology

• Why does the same logic puzzle get easy once you wrap a story around it?

  The Wason selection task shows four cards and a rule, and asks which cards you must turn over to check whether the rule is broken. Confirmation bias pushes people toward the cards that would confirm it. In the abstract version most people fail. In an identical logical structure with a different wrapper, they succeed. What changes it?

  Source: Cosmides, Cognition

• What does your brain already know about a word that escaped you?

  The sense that a word is right on the tip of your tongue feels like a complete failure of memory. To find out whether that is right, researchers drove people into the state deliberately with definitions of rare words, and then asked them what they did know. What did they know?

  Source: Brown & McNeill, Journal of Verbal Learning and Verbal Behavior

• Is a coin toss really fifty-fifty, or does the hand tilt it?

  A coin toss counts as the definition of randomness, which is why it settles arguments. A physical model predicted a wobble in the spin axis: the hand adds a minute tendency, depending on which face started upward. Forty-eight people threw a coin hundreds of thousands of times. What came out?

  Source: Bartoš et al., Journal of the American Statistical Association

• Your dog tilts its head when you talk. What is it doing in that moment?

  A dog tilting its head looks as though it is trying to hear better, and that is the usual explanation. Except that if it were right, every dog should do it equally often. The researchers followed forty dogs. What separated them?

  Source: Sommese et al., Animal Cognition

• The cat does not come when called. Does it at least know its name?

  A cat that does not come when called looks as though it does not know the name, but perhaps it simply is not coming. To separate the two, researchers played cats a run of similar words and then their own name. What happened?

  Source: Saito et al., Scientific Reports

• You were told you are a visual learner. Should you be taught only in pictures?

  The idea sounds sensible: work out whether a student prefers to see, to hear or to do, and then teach them that way. Except that proving it takes more than the student doing well; it takes different types doing well under different methods. What was found?

  Source: Clinton-Lisell & Litzinger, Frontiers in Psychology

• Wasps in a nest look alike. How does one tell who it is facing?

  In a wasp nest the individuals look much the same, and recognizing one from another was taken to be an ability of animals with large brains. Female paper wasps carry yellow and black markings that vary from one wasp to the next. What do they do with them?

  Source: Tibbetts, Proceedings of the Royal Society B

• Does living abroad really make a person more creative?

  A stamp in a passport teaches no new way of thinking on its own, and it is still common to say travel opens the mind. In three experiments people recalled an experience from another culture, some describing it and some explaining it. So what separated the two?

  Source: Maddux et al., Personality and Social Psychology Bulletin

• Does computer read-aloud help you understand a text, or only read it out?

  A text-to-speech tool sounds out the words while a student reads them, and it is easy to suspect it simply reads for them. But if decoding consumes attention, freeing that attention ought to help comprehension. What turned up among students with reading difficulties?

  Source: Wood et al., Journal of Learning Disabilities

• Is a tablet really harder to understand than a printed page?

  A tablet screen resembles a book far more than a desktop computer does: you hold it in your hand, it has no windows open on it, and it is a similar size. So you might expect the gap against print to vanish. What was actually found?

  Source: Salmerón et al., Journal of Educational Psychology

• How far is a therapist’s empathy tied to the success of therapy?

  Therapeutic empathy is not simply being nice but an attempt to understand a client’s experience precisely and respond so that they feel understood. That is hard to measure, so both client ratings and technical measures of accuracy were examined. Which predicted success?

  Source: Elliott et al., Psychotherapy

• If you learn your colleagues are saving for retirement, will you save more?

  Social encouragement is treated as an effective tool: tell someone that many people around them already do something, and they will tend to join. At an American company, letters went to employees making it easier to join a retirement plan, and some of the letters also carried that figure. What happened?

  Source: Beshears et al., The Journal of Finance

• Can you grow attached even to information that has no use?

  We tend to value an object we already own more than an identical one that is not ours. But information is not an object: you cannot hold it, and it stays with you even after you pass it on. So this was tested with facts that have no use at all. What happened?

  Source: Litovsky et al., PNAS

• Do music lessons or chess make a child better at subjects nobody practiced?

  A child who learns an instrument gets better at the instrument, and a child who plays chess gets better at chess. The interesting question is whether the training also lifts skills nobody practiced at all, which is what researchers call far transfer. Three reviews pooled the experiments and sorted them by how well each one was built. What happened to the effect?

  Source: Sala and Gobet, Current Directions in Psychological Science

• Why does a story stay in your head after you close the book?

  Something you read sometimes returns to mind on its own minutes later, and sometimes the text is gone the moment you close it. To find what separates the two, people read sequences of words that hung together as words, as sentences, or as a whole narrative. Then they were asked what came to mind. What stayed?

  Source: Nature Communications

• Does a vacation with meditation in it leave anything behind once you are home?

  The freshness of an ordinary holiday is well documented, and so is how fast it fades. This study followed 120 people who already meditated: some took a plain vacation, some practiced during theirs, and others went on an intensive retreat. What was left ten weeks afterwards?

  Source: PLOS ONE

• Why does telling a festival story together change the memory of it?

  When two friends remember the same night, one raises a moment the other had lost, and between them a single version gradually settles. That sounds like retrieval, and it may be construction. Researchers interviewed festival tourists alone and then in their pairs. What changed?

  Source: Journal of Travel Research

• Phone, laptop and television at once. Does that really make you easier to distract?

  A famous 2009 study reported that people who run several media at once filter distractions worse, and the claim felt too true to question. Later studies did not all find it. Two replications then ran 14 fresh tests and reported every one of them, and a meta-analysis pooled the literature. What survived?

  Source: Wiradhany and Nieuwenstein, Attention, Perception, and Psychophysics

• Why does applause spread through a hall even when the person beside you is silent?

  At the end of a talk one person starts clapping and the rest join, and the natural assumption is that it travels from neighbor to neighbor like a cough. Social contagion has plenty of mathematical models and very little data to test them against. Researchers recorded a real audience and compared the models. What actually makes a person clap?

  Source: Mann et al., Journal of the Royal Society Interface

• A witness sounds completely certain. Does that certainty mean anything?

  Courts increasingly accept that the confidence of an eyewitness says little about whether the identification is right. That pessimism was entirely reasonable given the lineup procedures police used to run. After thirty years of research on how to run one properly, a review asked a narrower question: when exactly was the confidence measured?

  Source: Wixted and Wells, Psychological Science in the Public Interest

• Would you shock yourself rather than sit and think?

  Sit in a room with no phone, no book and no task, for somewhere between six and fifteen minutes, and think. It is the easiest instruction anybody will ever give you, and it might even be pleasant. Across eleven studies, people kept rating it below every dull alternative on offer. How far below?

  Source: Wilson et al., Science

• Why is the thing you assembled yourself worth more to you?

  Build a piece of furniture and it becomes better in your eyes than the identical piece somebody else built. The usual explanations are effort, which should mean more work makes it dearer, and ownership, which should mean holding it is enough. A set of studies in children tested both. Which survived?

  Source: Marsh, Kanngiesser and Hood, Cognition

• Does seeing something again and again make you like it more?

  The mere exposure effect says familiarity breeds liking, and it is one of the most repeated findings in social psychology. If it were simply true, more exposure would always mean more liking. A meta-analysis pulled 268 curve estimates out of 81 articles to see what shape the relationship actually has.

  Source: Montoya et al., Psychological Bulletin

• Would you notice if your own choice were swapped?

  Theories of decision-making assume we detect mismatches between what we intended and what happened, correct the error and adapt. That assumption is rarely tested against a case where the mismatch is handed to you. Participants picked the more attractive of two faces, and sometimes got the other one.

  Source: Johansson et al., Science

• How does a mood travel from one person to another?

  Sit with someone cheerful and you tend to leave cheerful. That might be courtesy, or inference, or something more mechanical. Scholars from a wide variety of disciplines have been studying what carries it. The classic answer involves the face, and the face does more than display.

  Source: Hatfield et al., Interpersona

• Why does the first number you hear change your answer?

  People judge probabilities and frequencies constantly without any way to calculate them. The question is what they do instead. Tversky and Kahneman described three mental shortcuts that stand in for the calculation, and one of them explains why a price tag works on you before you have thought about it.

  Source: Tversky and Kahneman, Science

• Does holding someone’s hand change what fear looks like in the brain?

  Social contact goes with better health and well-being, probably because other people help regulate how we respond to stress. That is an explanation at the level of a life. Sixteen married women went into a scanner under threat of electric shock to see it at the level of a scan.

  Source: Coan, Schaefer and Davidson, Psychological Science

• Can parents be coached into better talk with a baby?

  Parental language input is one of the best predictors of children’s language achievement. Parentese, the near-universal style with higher pitch, slower tempo and exaggerated intonation, is associated with language gains, and so is turn-taking. Association is where that research stopped.

  Source: Ferjan Ramírez, Lytle and Kuhl, PNAS

• Does the way you praise a toddler matter five years later?

  In laboratory studies, praising a child’s effort encourages an incremental framework: ability is malleable, success comes from hard work, challenges are enjoyable. Praising inherent ability encourages a fixed one. Whether the praise parents give at home does the same thing is a different question, because home is not a laboratory.

  Source: Gunderson et al., Child Development

• What does a minute in front of a breathtaking landscape do to a person?

  Gardens, parks and waterfronts dominate the work on nature and wellbeing, because they stir little and so leave the restorative effect clean to measure. That leaves out the kind of nature that stops you where you stand. Joye and Bolderdijk showed people slideshows of spectacular scenery instead. What moved, and what did not?

  Source: Joye and Bolderdijk, Frontiers in Psychology

• Does the full moon really keep people awake?

  The belief is old and the evidence was thin. Then a laboratory study in two thousand and thirteen reported that nights around the full moon came with less total sleep, shallower deep sleep and longer latencies, all in light-controlled conditions. It looked like folk wisdom vindicated. Cordi and colleagues went to their own archives of sleep recordings. What came back?

  Source: Cordi et al., Current Biology

• How long does the good of a long holiday last once you are back?

  Vacations appear to have strong but short-lived effects on health and wellbeing, and the research has mostly looked at short breaks. The obvious thought is that a longer one would hold better. De Bloom, Geurts and Kompier followed employees through summer vacations averaging twenty-three days, measuring before, during and repeatedly afterward. How long did it hold?

  Source: de Bloom et al., Journal of Happiness Studies

• What did the neighbors of the most famous murder in New York actually do?

  A woman was stabbed outside her building in Queens in nineteen sixty-four. Two weeks later a newspaper headline said thirty-seven people saw it and none called the police, and that sentence became the founding story of an entire psychological phenomenon. The crime itself had made only a brief news item. The coverage is what traveled. Does it hold up?

  Source: History.com

• Which study habit actually keeps things in memory?

  A German psychologist reported the answer more than a hundred and thirty years ago, and hundreds of studies since have agreed with him. It costs nothing, needs no technique and beats the method almost everyone defaults to the night before a test. What is strange is that nobody can say exactly why it works. What is it?

  Source: BrainFacts, Society for Neuroscience

• Does a bigger range of options really make people choose worse?

  The choice overload hypothesis holds that more options can backfire, cutting the motivation to choose at all or the satisfaction with whatever gets chosen. Strong instances turned up in the laboratory and in the field, and the idea became common knowledge. Other studies found nothing, or the opposite. Scheibehenne, Greifeneder and Todd pooled the lot. What is the average?

  Source: Scheibehenne et al., Journal of Consumer Research

• What gets through while you are ignoring everyone else at a party?

  The mind can process only so much at once, so attention works like a bottleneck. Broadbent argued the filter sorts incoming sound by physical properties, pitch, volume, which ear it arrives in, and discards the rest before meaning is reached. Colin Cherry had already shown how much the physical cues matter. Then someone tested one particular word.

  Source: Simply Psychology

• Does a crowd really make people less likely to step in?

  Half a century of work says the more bystanders present at an emergency, the less likely any one of them helps. Recent meta-analytic evidence questioned whether that carries over to violent emergencies, where some argued the effect reverses. A separate line of research points elsewhere entirely, to who knows whom. Liebst and colleagues went to the surveillance tapes.

  Source: Liebst et al., Aggressive Behavior

• What does hearing the same unverified claim nine times do to you?

  Repeat a moderately plausible statement of unknown truth and people rate it likelier to be true than one they have not heard, an effect that even works on statements first labeled false. Most studies used two or three repetitions. DiFonzo and colleagues ran it out much further, with rumors embedded in narratives, and asked what shape the curve takes.

  Source: DiFonzo et al., Social Influence

• What is an outdoor guide actually arranging, besides the canoe?

  Slow adventure means canoeing, stargazing, foraging: activities marked by a slower passage of time, immersion in the natural world and belonging to a small group. A guide takes people into that, and the usual account of the job is logistics and safety. Farkic, Filep and Taylor asked ten guides in the Scottish Highlands and Islands what they think they are doing.

  Source: Farkić et al., Journal of Sustainable Tourism

• Why do two people walking toward each other almost never collide?

  Walking through a station, you continuously adjust your path to keep a comfortable distance from strangers and to avoid hitting them, and you do it without deciding to. Modeling that has been hard because real avoidance events are buried inside enormous, messy tracking data. Corbetta and colleagues had six months of it from a train station. What does the maneuver look like?

  Source: Corbetta et al., Physical Review E

• Which small moment between partners shows up again the next day?

  When someone does something thoughtful for you, two different feelings are available. One is gratitude. The other is indebtedness, the sense of owing, and the two have opposite emotional colors despite coming from the same event. Algoe, Gable and Maisel followed both members of cohabiting couples day by day to see which one does anything for the relationship.

  Source: Algoe et al., Personal Relationships

• What makes a museum visit teach a child anything?

  Museums have spent decades adding things for children to touch, press and play with, on the understanding that interactivity is what makes a visit educational. That leaves the designer with three separate levers: other people, technology, and the exhibit space itself. Andre, Durksen and Volman reviewed a decade of research to find which of them does the work.

  Source: Andre et al., Learning Environments Research

• Who gets less out of the same holiday?

  The Type A behavior pattern left the research literature in the early nineties, once its link to heart disease failed to replicate. The pattern itself, speed, impatience, perfectionism, drivenness, hostility, did not go away. Smith and Bryant asked whether it still explains something: not how long people live, but how much they enjoy their own time off.

  Source: Smith and Bryant, International Journal of Wellbeing

• What kind of evening together actually changes how a couple feels?

  Relationship quality typically declines after the honeymoon period, and boredom is one candidate explanation. If that is right, then doing something new together should work better than doing something pleasant and familiar. Aron and colleagues tested it five ways, including three laboratory experiments where the activity lasted seven minutes.

  Source: Aron et al., Journal of Personality and Social Psychology

• What is left of the claim that standing in a wide stance changes you?

  A two thousand and ten experiment reported that people who held expansive postures felt more powerful, took more risk, and showed higher testosterone and lower cortisol. The TED talk built on it argued that such poses can change the outcomes of your life. Dozens of published studies followed, all showing effects. Simmons and Simonsohn asked whether that record means anything.

  Source: Simmons and Simonsohn, Data Colada

• Why does losing ten dollars hurt more than finding ten dollars pleases?

  Economics long assumed a self-interested agent capable of rational decisions, and judged choices against the expected outcome for total wealth. Kahneman and Tversky kept finding people doing something else in the laboratory, consistently enough that the pattern was not noise. The Nobel committee describes what they found, and it starts with what people compare against.

  Source: The Royal Swedish Academy of Sciences

• Should a newlywed couple pool their money into one account?

  Couples who get serious about each other hit a money question early: one pot, or two. Almost everything known about it is correlational, because nobody randomly hands a couple a bank account. Consumer researchers did exactly that, assigning engaged and newlywed couples an account structure and following them through six waves across the first two years of marriage. Did the structure move anything?

  Source: Journal of Consumer Research

• Does feeling understood by your partner change how you feel ten years later?

  Attachment researchers treat one belief as the core of a close relationship: that your partner cares about you, appreciates you and gets you. More than two thousand married American adults rated that belief, then rated their own well-being again a decade on, with personality and the responsiveness of friends and family held constant. Which kind of well-being, if any, moved?

  Source: Journal of Marriage and Family

• How long does the dip in marital satisfaction after a first baby last?

  A first baby arrives and the marriage changes, which almost nobody disputes. Earlier syntheses stopped counting at the end of the first year, so the shape of the curve after that was guesswork. This meta-analysis pooled 49 studies, 97 samples of parents against 9 samples of non-parents, and carried the line out to two years. Where does it level off?

  Source: Frontiers in Psychology

• What happens to the talk in a home when a toddler’s screen time goes up?

  Children learn language from the talk around them, so the worry about screens is not really about the screen. It is about what the screen replaces. Australian researchers put recorders on 220 families and captured an average sixteen-hour day, five times between the ages of twelve and thirty-six months. Did the household words actually go missing?

  Source: JAMA Pediatrics

• Can you hear how good a relationship is from when the couple laughs?

  Laughter is almost always social, and yet hard data tying it to how a relationship is going is scarce. Two researchers filmed 71 heterosexual couples telling the story of how they met, coded every spontaneous laugh, and asked what fraction of the conversation the pair spent laughing at the same moment. Does the timing carry something the amount does not?

  Source: Personal Relationships

• Does drawing a word fix it in memory better than writing it out?

  Students copy terms out to learn them, and the honest answer about whether copying works is not encouraging. A memory lab ran seven experiments pitting one instruction against another: draw each word on the list, or write it. Then the authors went after every ordinary explanation for whichever way the result fell. What survived that?

  Source: Wammes et al., Quarterly Journal of Experimental Psychology

• Can fifteen minutes of exercise change the kind of thinking you are capable of?

  Short bouts of exercise reliably nudge attention and memory, and creativity has gone largely untested. Forty healthy young adults drew either fifteen minutes of aerobic exercise or a control condition. Then came two very different creativity tasks: one asking for many uses of an ordinary object, one asking for the single right insight. Mood ratings followed. Which task budged?

  Source: Aga et al., Brain Sciences

• Does taking more vacations leave any lasting mark on how happy you are?

  The standard line on holidays is that the lift is real but brief, mostly a matter of mood, and gone within weeks. Two researchers point out that almost every study behind that line ran for a year or less, which is too short to see anything slow. So they took eight years of panel data from a representative Dutch sample. What shows up at that length?

  Source: Journal of Happiness Studies

• What has to happen in your head for something to count as awe?

  Awe gets used loosely, somewhere between wonder and being impressed. The emotion literature describes something far more specific, with two components that both have to be present. A systematic review gathered 57 studies of awe and read them through a cognitive behavioral lens to build a model of how the emotion works. What are the two parts?

  Source: International Journal of Applied Positive Psychology

• Can you tell hot water from cold just by the sound of it pouring?

  Ask anyone whether they can hear the temperature of water being poured and the answer is a flat no. The physical attributes of pouring water do change with temperature, though, and those changes reach the ear. So researchers tested listeners on recordings of water being poured, and set a pre-trained deep neural network the same job. Who was right about what people can do?

  Source: Frontiers in Psychology

• Does REM sleep solve the problem, or only rearrange it?

  REM sleep has long been called a hyperassociative state, one that links concepts too distant to meet while you are awake. That is the standing explanation for sleeping on a problem. Participants worked a riddle, took a ninety-minute break containing REM sleep, non-REM sleep only, or wakefulness, and worked it again, with their semantic networks and their EEG tracked throughout. Did the break deliver an answer?

  Source: Communications Biology

• Can a colored light on a screen change how much a shock hurts?

  Expectation is the engine almost everyone points to when they explain placebo, and expectation itself is hard to catch in the act. One lab reached for a slow brain wave that builds while you wait for something, the contingent negative variation. Volunteers saw a green or a red cue, then took electrical stimuli whose intensity never actually changed. Did the cue reach the pain?

  Source: European Journal of Pain

• Does having more money make a person more willing to cut corners?

  Folk wisdom runs both ways on wealth and honesty, which is usually a sign nobody has measured it. One research group built seven studies around the question. Two watched real drivers to see who broke the law at the wheel. Five moved into the lab, covering unethical decisions, taking valued goods, lying in a negotiation, cheating for a prize and endorsing bad conduct at work. Which way did it fall?

  Source: Proceedings of the National Academy of Sciences

• What about reading a story to a child actually teaches the words?

  Preschoolers pick up vocabulary from picture books, and that much has been documented many times over. What nobody had pulled together is which parts of the reading do the work. A meta-analysis gathered 38 studies covering 2,455 children and 110 effect sizes, then tested one candidate after another against word comprehension. Which features mattered, and which turned out not to?

  Source: Developmental Psychology

• Can six weeks of training change how a parent handles a child’s feelings?

  Tuning in to Kids teaches parents to coach a child through a feeling instead of shutting it down, and its evidence came almost entirely from Western families. So a Hong Kong team ran a randomized controlled trial with 104 parents of three to six year olds, mostly mothers, on low to middle incomes. Half took the six-week course and half waited. What moved, and when?

  Source: Developmental Psychology

• Does a hug from your partner before a stressful moment do anything measurable?

  Massage blunts the stress response in women, while the other forms of social touch had gone largely unexamined and men had barely been studied at all. One lab took the commonest form of touch there is, the embrace, and had couples hug briefly before a laboratory stressor built to feel socially humiliating. Cortisol, blood pressure and self-rated mood all got recorded. Which of the three moved?

  Source: PLOS ONE

• What is the right thing to say when someone tells you good news?

  Relationship advice concentrates almost entirely on handling the bad days, which leaves the good ones unexamined. Four studies looked at what happens when people seek someone out after something goes right, a move researchers call capitalization, and at how the listener answers. Daily diaries tracked mood, well-being and the state of the relationship. Does the reply matter, or is telling someone enough?

  Source: Journal of Personality and Social Psychology

• Can teaching new parents to read a baby’s cues change the child’s weight at three?

  Fast growth in the first years raises the risk of later obesity, and interventions that bend the growth curve have been thin on the ground. The INSIGHT trial randomized first-time mothers to one of two home visiting curricula: one on answering a baby’s cues around feeding, sleep, play and emotion, one on home safety. Nurses visited four times in infancy. What did the scales say at three?

  Source: JAMA

• Does letting a baby cry it out leave a mark a year later?

  The fight over infant sleep training is mostly a fight about harm rather than about sleep. Both sides accept that the methods work, and the question is what they cost. So a trial randomized 43 infants aged six to sixteen months to graduated extinction, to bedtime fading, or to a sleep education control. It sampled their cortisol, and brought the mothers and children back a year later. What did the follow-up find?

  Source: Pediatrics

• How do you get a preschooler to like a vegetable they have already rejected?

  Advice to parents about fussy eating usually arrives as information: a leaflet, a word about nutrition, an explanation of why vegetables matter. A trial put that against something far duller. 156 parents of two to six year olds picked a vegetable their child already disliked, then drew one of three groups: taste it daily for a fortnight, receive nutrition advice, or do nothing at all. Whose children changed?

  Source: Appetite

• Does a bedtime routine on its own improve a young child’s sleep?

  Every parenting book recommends a consistent bedtime routine, and it almost always arrives bundled with sleep training, so nobody had tested the routine by itself. Two age-matched trials put that right. 405 mothers of children between seven and thirty-six months kept a week of baseline, then drew either a specific nightly routine or their usual one. Can the routine alone carry the effect?

  Source: Sleep

• Does photographing something make you remember it worse?

  A camera is supposed to help you keep a day, which raises the question of what it does to the copy in your head. Participants went on a guided tour of an art museum, told to observe some objects and to photograph others. Afterward their memory for the objects, the details and the locations got tested. Two studies, with one instruction changed in the second.

  Source: Henkel, Psychological Science

• Does giving something up for your partner help the relationship?

  The question usually gets asked as though sacrifice were one thing, with the answer somewhere between noble and corrosive. Eighty dating couples went through a three-part study: discussing a sacrifice in the lab, logging their daily sacrifices for a fortnight, and answering again three months later. What the researchers watched was not how much people gave up, but why. Does the reason change the outcome?

  Source: Journal of Personality

• Do babies really prefer the puppet that helps over the one that hinders?

  A 2007 experiment became one of the most cited results in infant research. Babies watched a character struggle up a hill, then reached for the puppet that had helped rather than the one that had hindered. Replications since have come out mixed. So 37 labs on five continents ran one preregistered, standardized version, testing 1018 infants between five and ten months old. What did the big version show?

  Source: Lucca et al., Developmental Science

• Does skin-to-skin contact with a premature baby still show up twenty years on?

  Kangaroo mother care puts a preterm baby skin to skin on a parent’s chest. A Colombian randomized trial run between 1993 and 1996 found benefits at one year for survival, neurodevelopment, breastfeeding and bonding. The obvious question is whether any of that lasts. Two decades later the same team went looking for the same people. How much of the original effect was still there?

  Source: Pediatrics

• What matters more after a fight, how it went or how you came down from it?

  Couples research has studied the argument itself exhaustively and said very little about the four minutes afterward. One team brought in 73 young adults who had been followed since birth, along with their romantic partners, and had each couple hold a ten-minute conflict discussion followed by a four-minute cool-down task. Coders rated how far each person disengaged. Does the climbdown predict anything?

  Source: Psychological Science

• Can a goat tell a smiling face from an angry one?

  Dogs and horses were bred to work alongside people, so their sensitivity to a human face surprises nobody. Goats were bred for milk and meat. Researchers hung two photographs of the same unfamiliar person on a wall, one happy and one angry, 1.3 meters apart, and released goats from four meters away to do as they liked for thirty seconds. What did the goats go to?

  Source: Nawroth et al., Royal Society Open Science

• Can an elephant tell from a voice whether the person is dangerous?

  Humans are an odd sort of predator, because the danger depends entirely on which humans. Prey species were already known to sort people by sight and by smell, and a voice carries far more than either. So researchers played recordings to free-ranging elephant family groups in Amboseli and watched what the herds did. The recordings varied the speaker’s ethnic group, sex and age. How fine is the distinction?

  Source: McComb et al., PNAS

• Can a raven hold on to a tool for a job that is seventeen hours away?

  Planning for something outside the present moment has long been treated as a hominid invention, with the ape studies as its evidence. Corvids do cache food for later, which looked like a narrow adaptation for hoarding rather than planning in general. So two researchers set ravens tasks with nothing to do with caching: using a tool, and bartering with a person. What did the birds do with the delay?

  Source: Kabadayi and Osvath, Science

• Does your cat know your voice, and would it show you if it did?

  Cats have lived alongside people for ten thousand years, and how much they take in of us has barely been tested. One lab played 20 domestic cats three strangers’ voices in a row, each calling the cat by its own name, with the owner out of sight. Then came the owner’s voice. Ten naive raters scored the magnitude of every reaction. Does anything register?

  Source: Saito and Shinozuka, Animal Cognition

• Will a rat play hide-and-seek with you for nothing but the game?

  Mammals play, and why they do it remains unsettled, partly because most laboratory play is really food training in disguise. One lab removed the food. Researchers taught rats hide-and-seek, paying them only in playful interaction after a find, and recorded from the prefrontal cortex while the animals took turns. Hide-and-seek needs roles, rules and a memory of where you looked. Could a rat hold all three?

  Source: Reinhold et al., Science

• Can a newly hatched duckling learn an idea rather than an object?

  Imprinting is the textbook case of rigid learning: a hatchling fixes on whatever it meets first and follows that. A handful of animals have shown relational concept learning, but only after long stretches of reinforcement training. So two researchers briefly showed newly hatched mallards a pair of objects, either matching or mismatching in shape or color, and then offered pairs of completely new objects. Which pair did the ducklings follow?

  Source: Martinho and Kacelnik, Science

• Can a new trick spread through a colony of bumblebees like a custom?

  Culture, in the minimal sense, means a group-specific behavior passing from an innovator to everybody else. Whether that needs a clever brain is the open question. So one lab set bumblebees an unnatural task, pulling a string to drag an out-of-reach reward closer, and then watched what happened when a single trained bee was put back among untrained nestmates. Does the trick travel, and does it need insight?

  Source: Alem et al., PLOS Biology

• How does a crow that has never been caught learn which face to avoid?

  Information gained firsthand is accurate and expensive; information taken from a neighbor is cheap and may be wrong. Every animal trades the two off. Researchers wore a distinctive mask while trapping, banding and releasing crows at five sites near Seattle, then came back for years wearing the same mask and a neutral one. Who scolded the dangerous face, and how far did the knowledge travel?

  Source: Cornell et al., Proceedings of the Royal Society B

• Can a sheep pick a familiar face out of a photograph it has never seen before?

  Sheep recognize other sheep and recognize the people who handle them, which could be done on smell, gait or voice. Whether they process a face as a whole was unknown. So eight sheep were trained to pick out four celebrity portraits on computer screens, and then given the harder version: the same four faces photographed from a different angle. Does the recognition survive the tilt?

  Source: Knolle et al., Royal Society Open Science

• Will a cuttlefish turn down a decent meal to wait for a better one?

  Waiting for something better is cheap to describe and expensive to do, and across animals the tolerable delay runs from a few seconds to several minutes. The long waits belong to large-brained vertebrates, all of which face broadly similar social and ecological pressures, so nobody can say which pressure built the ability. A cuttlefish faces partly different ones. How long will it hold out?

  Source: Schnell et al., Proceedings of the Royal Society B

• Does a horse know the difference between a smile and a scowl?

  Horses read each other with a facial repertoire as rich as a dog’s, and whether they read ours was untested. The hard part is proving an animal understood a face rather than merely noticed it. So researchers showed horses photographs of happy and angry human expressions, with no training and no reward, and measured two things the horse cannot fake: which eye it looked with, and its heart rate.

  Source: Smith et al., Biology Letters

• Who is most affected by treating a search engine as their memory?

  The Google effect is the claim that people lean on the internet as a store of knowledge instead of holding it themselves. It has been asserted far more often than it has been pooled. A meta-analysis gathered the scattered studies and asked a different question from the usual one: not whether the effect exists, but which conditions and which people it attaches to. Who turned out most exposed?

  Source: Gong and Yang, Frontiers in Public Health

• Does a few minutes of literary fiction make you better at reading people?

  A 2013 result became one of the most repeated findings in the humanities: read a few pages of literary fiction and your ability to read other minds improves on the spot. A later team failed to replicate it, the original authors objected on three specific methodological grounds, and this paper is the answer to those objections. Including a reanalysis done the way the critics asked for. What came out of that?

  Source: Panero et al., Journal of Personality and Social Psychology

• When in a holiday are you actually at your happiest?

  Holidays are sold on the return: the recharged person coming back to work. A Dutch study measured 1,530 people before and after, with 974 of them actually taking a trip, and compared them against people who stayed home. Both ends of the holiday were on the record, which lets the before and the after be weighed against each other. Which end came out ahead?

  Source: Nawijn et al., Applied Research in Quality of Life

• What is a brain doing while a story keeps you hanging?

  Suspense is the emotion that holds a reader, and it looks like it ought to be made of ordinary machinery: expectation, anticipation, prediction. Nobody had looked at the neural side of it. So participants read a suspenseful literary text in a scanner, broken into short passages, and rated how much suspense each passage produced. Then the ratings were set against the imaging. Which areas tracked the tension?

  Source: Lehne et al., PLOS ONE

• Pen or keyboard for a child who is just meeting letters?

  Two reasonable arguments point opposite ways. Typing is physically easy, which should suit a child whose fine motor control is still arriving. Handwriting couples the movement to the shape, which should lay down a sensory-motor trace that typing never does. So a German team built 16 training sessions of closely matched letter games, teaching eight letters by pen or by keyboard. Which children came out ahead?

  Source: Kiefer et al., Advances in Cognitive Psychology

• If you are told a wine is expensive, does it actually taste better?

  That a price tag moves what people say about a wine is old news, and so is the finding that it moves the brain signal too. What stayed unexplained is the step in between: how an expectation gets converted into an actual sensation of pleasantness. So participants tasted identical wines labeled with different prices inside a scanner, and the authors traced the route rather than the outcome. Where does the conversion happen?

  Source: Schmidt et al., Scientific Reports

• Does a mindful walk have to be in nature to do you any good?

  Nature is treated as the active ingredient in walking interventions, which makes the street the thing you settle for. Testing that needs a comparison nobody usually runs. So 104 university students with sleep difficulties were randomly allocated to walk mindfully for 35 minutes a day for a week, either in a natural setting or an urban one. Sleep, mood and mindfulness were rated four times. Did the trees add anything?

  Source: Ma et al., Explore

• If you were attacked in the street, would anybody actually step in?

  Half a century of research says each individual is less likely to help when others are present. That is a claim about one person’s odds, and it has been read as a claim about crowds, which is not the same thing. Nobody had asked the question a victim actually cares about. So researchers coded surveillance camera footage of 219 real public conflicts across three countries. Does anyone help?

  Source: Philpot et al., American Psychologist

• Does resisting one temptation really leave you weaker against the next?

  Willpower as a finite resource is one of the most exported ideas psychology has produced. The laboratory version is the sequential-task paradigm: do one self-control task, then do worse on a second. An early meta-analysis put the effect at medium size, and later ones questioned both the size and the existence of it, and flagged possible bias. So 23 labs ran one preregistered protocol. What was left?

  Source: Hagger et al., Perspectives on Psychological Science

• How much does believing intelligence can grow actually raise a student’s grades?

  Mindset theory holds that believing abilities are malleable brings better outcomes, achievement among them, while believing them fixed brings worse ones. Schools around the world adopted interventions built on that. Two meta-analyses then asked the size question from both ends: how strongly mindset and achievement are related, across 365,915 students, and how well the interventions work. What did the pooling give?

  Source: Sisk et al., Psychological Science

• Can a computer game in the first hours after a crash change what you remember?

  Intrusive visual memories after trauma are distressing, disruptive, and almost nothing exists to prevent them. Laboratory work suggested a reason to try something odd: a game with heavy visuospatial demands might interfere while the sensory part of the memory is still consolidating. So an emergency department trial gave patients a trauma reminder cue plus about 20 minutes of Tetris within six hours of a road accident. Did the intrusions change?

  Source: Iyadurai et al., Molecular Psychiatry

• If you hold a pen in your teeth, do cartoons get funnier?

  The facial feedback hypothesis says your own expression feeds back into how you feel, even when the expression came from nowhere emotional. The famous demonstration had people rate cartoons while holding a pen in the teeth, which forces something like a smile, or in the lips, which forces something like a pout. It had never been replicated directly. So 17 labs ran one vetted protocol. What came out?

  Source: Wagenmakers et al., Perspectives on Psychological Science

• Can an animal know it made the wrong choice a moment ago?

  Disappointment and regret are not the same feeling. Disappointment is getting less than you expected; regret is recognizing that a different action of yours would have done better. In people the orbitofrontal cortex tracks regret, and people with damage there do not express it. So one lab built a rat task where skipping a cheap offer and then meeting an expensive one creates exactly that structure. What did the rats do?

  Source: Steiner and Redish, Nature Neuroscience

• Does speaking two languages sharpen the rest of your thinking?

  The argument is intuitive: a lifetime of holding two languages apart should train the machinery that holds anything apart. Decades of work later there is still no consensus about whether the advantage exists. So a team pooled 891 effect sizes from 152 adult studies across six executive domains, added unpublished data, and then did the step most reviews skip: corrected for publication bias. What survived the correction?

  Source: Lehtonen et al., Psychological Bulletin

• Can being told you slept badly actually make you think worse?

  A placebo is any outcome that comes from a mindset rather than from a treatment, and the idea need not stay inside pharmacology. Sleep is a good test case, because almost everybody believes a bad night costs them mentally. So 164 participants reported how they had slept, then got told a figure for their own REM sleep that was assigned rather than real. Did the number do anything to their performance?

  Source: Draganich and Erdal, Journal of Experimental Psychology: Learning, Memory, and Cognition

• Can you ask a sleeping person a question and get an answer back?

  Everything known about dreams comes from reports written after waking, and those are distorted by forgetting and by reconstruction. That is a foundational problem for studying dreaming at all. The way around it would be to reach someone while they are still inside the dream, which means someone inside a lucid dream, aware that they are dreaming. Four laboratory groups tried it in 36 people during verified REM sleep. Did anyone answer?

  Source: Konkoly et al., Current Biology

• Can you catch somebody else’s fear by smelling it?

  Earlier work had found that body odor from frightened people produces implicit fear in whoever smells it. What nobody had pinned down is the plumbing: which stress system actually releases the stuff. The armpit glands responsible for chemical signals carry receptors for adrenalin, which points at the fast system rather than the slow one. So sweat was sampled from people preparing a speech. Which system delivered?

  Source: de Groot et al., PLOS ONE

• Does a bad night’s sleep decide how the next argument goes?

  Couples research reaches for personality, attachment and communication skill to explain why a conflict goes badly. A much duller candidate sits underneath all of them. So two studies tested it. One was a fourteen-day daily experience study tracking conflict against the previous night’s sleep. The other brought couples into a laboratory for a conflict conversation, with both partners’ sleep on the record. Does sleep show up?

  Source: Gordon and Chen, Social Psychological and Personality Science

• Does talking to yourself by name actually calm you down?

  Silently referring to yourself by your own name, and using pronouns other than I, has been shown to help regulate emotion. Two obvious doubts remained. Perhaps it works only on mild upsets, and perhaps it fails for the people who most need it. Two high-powered experiments tested both, across negative experiences varying in intensity and in people scoring high on emotional vulnerability.

  Source: Orvell et al., Clinical Psychological Science

• Which investments do people find hardest to sell?

  Selling a stock that has fallen means admitting the purchase was a mistake, and selling one that has risen means banking a win. Those two feel very different and should not, since what matters is what each stock does next. The disposition effect names the resulting bias. So the trading records of 10,000 accounts at a large discount brokerage were examined. Which way did it run?

  Source: Odean, The Journal of Finance

• Why do the most speculative stocks all rise and fall together?

  Some stocks have lottery features: cheap, volatile, and offering a small chance of an enormous payoff. They attract a particular kind of buyer. If those buyers trade on the same impulse rather than on company news, the stocks should move together more than their businesses can explain. So the study looked for excess comovement, and then went to the actual trades to find out who was producing it.

  Source: Kumar et al., Journal of Financial and Quantitative Analysis

• What does scrolling through hundreds of profiles do to your judgment?

  Online dating offers more opportunities to find a partner than any previous arrangement, and more people are single than before. One way to square that is a rejection mind-set: continued access to effectively unlimited options makes a person more pessimistic and more rejecting as they go. That predicts something specific and measurable, namely a drift across a session. So three studies watched the drift.

  Source: Pronk and Denissen, Social Psychological and Personality Science

• Does a society get less generous when it loses an hour of sleep?

  Helping each other is among the more consequential things our species does, and what determines whether someone chooses to help is not well pinned down. Sleep is an unglamorous candidate. Three replicating studies tested it at three scales at once. They were one night of sleep loss in the laboratory with imaging, several nights tracked in daily life, and a whole country losing an hour to Daylight Saving Time.

  Source: Ben Simon et al., PLOS Biology

• Do conversations finish at the moment anyone involved wanted them to?

  Social connection underwrites physical and psychological well-being, and conversation is the main way people get it. Science knows remarkably little about the mechanics: how a conversation starts, how it unfolds, how it ends. Ending is the part everyone has opinions about and nobody has measured. So researchers asked people, after conversations, when they had actually wanted to stop. Did the wish and the ending line up?

  Source: Mastroianni et al., PNAS

• Do two brains fall into step when the conversation is by text?

  Texting is now one of the commonest ways people interact, especially among the young, and what it does to the social brain is unknown. Talking face to face produces measurable synchrony between two brains. Whether a conversation conducted from separate rooms produces any was untested. So 65 mother-adolescent pairs were recorded with hyperscanning EEG, talking in person and then texting from different rooms.

  Source: Schwartz et al., Scientific Reports

• Does a bored teacher make a bored class?

  Boredom is a standing student complaint and it tracks worse motivation, strategies and achievement. The obvious suspect is the person at the front. Testing that properly needs the teacher’s own boredom measured too, not just inferred from the class. So 437 students and 17 of their teachers kept a two-week diary, with 2,675 post-class evaluations analyzed by multilevel modeling. Does the boredom transfer?

  Source: Tam et al., British Journal of Educational Psychology

• How long can a baby hold on to a tune it heard before being born?

  Hearing develops through the last trimester, and near-term fetuses can tell frequencies apart and remember sounds that recur. The ceiling on the evidence was the retention interval: a few days after birth and no further. So one team played a descending piano melody twice daily through weeks 35 to 37 of gestation, then came back six weeks later with that melody and an ascending one. Would anything still register?

  Source: Granier-Deferre et al., PLOS ONE

• Does anything stay with you from words played while you fall asleep?

  Awareness of the world fades at sleep onset while the brain keeps processing sound in surprising detail. In waking life that kind of processing leaves a memory behind. Whether it does during sleep is a different question. So participants sorted spoken items into words and pseudo-words with left and right hand responses while drifting off, and were tested after waking. Did anything survive?

  Source: Andrillon and Kouider, Neuroscience of Consciousness

• Can your brain recognize a face that you cannot?

  Developmental prosopagnosia means growing up unable to recognize faces, including famous ones and sometimes close family. Whether anything is working underneath has been argued about for years, mostly from behavior. So 12 people with the condition judged famous and non-famous faces as familiar or not, with electroencephalography running throughout. The interesting trials are the failures. What does the brain do when the person says they do not know a face?

  Source: Eimer et al., Brain

• Does a drink really help you speak a language you have just learned?

  Dutch courage is one of the few folk beliefs about alcohol that sounds testable, and nobody had tested it on actual language learners. The complication is that a drinker’s own judgment is the least reliable instrument available. So fifty native German speakers who had recently learned Dutch were randomized to a low dose of alcohol or a control drink, then held a conversation in Dutch. Who was the judge?

  Source: Renner et al., Journal of Psychopharmacology

• Why does a word stop looking like a word if you write it enough times?

  Déjà vu has been studied for decades and its opposite has barely been touched. Jamais vu means finding something subjectively unfamiliar that you know perfectly well to be familiar. Producing it on demand would make it testable, so participants copied a single word over and over, stopping when it felt peculiar, when the task ended, or whenever else they wanted. How long does it take, and does it happen to everyone?

  Source: Moulin et al., Memory

• Can a cat be both a solid and a liquid?

  A rheologist took the question seriously enough to publish on it. Marc-Antoine Fardin used fluid dynamics to probe whether a cat can be both, and the Ig Nobel committee gave him its 2017 Physics Prize for doing so. The paper is called "On the Rheology of Cats", and it appeared in the Rheology Bulletin.

  Source: Improbable Research, Ig Nobel Prize winners

• Why is it easier to carry coffee walking backwards?

  Somebody studied it properly. Jiwon Han investigated the dynamics of liquid-sloshing to find out what happens when a person walks backwards carrying a cup of coffee, and won the 2017 Ig Nobel Prize in Fluid Dynamics for it. His paper is "A Study on the Coffee Spilling Phenomena in the Low Impulse Regime". He was a high school student when he wrote it.

  Source: Improbable Research, Ig Nobel Prize winners

• When does reading on paper actually beat reading on a screen?

  Most clearly when you are short of time. Delgado and colleagues pooled research from 2000 to 2017 comparing comparable texts read on paper and on digital devices: thirty-eight between-participants studies and sixteen within-participants, with a hundred and seventy-one thousand participants. Both designs gave the same advantage of paper, at a Hedge’s g of minus 0.21.

  Source: Delgado et al., Educational Research Review

• Do investors who look more often make the classic mistake less?

  On this evidence, yes. The disposition effect is the tendency to sell winners and hold losers. Dierick and colleagues used a brokerage dataset covering individual investors’ logins as well as their trades, which lets attention be measured rather than inferred. More attentive investors traded less in line with the disposition effect.

  Source: Dierick et al., Journal of Economic Behavior & Organization

• Is it the novelty of travel that makes it enjoyable?

  Partly, and the study can say how. Novelty, meaning the experience of something new and different from the everyday, is widely believed to be what defines tourism and makes it enjoyable. Mitas and Bastiaansen tested that as a mediation question in two longitudinal datasets of daily psychometric diaries, and found the effect of tourism on positive emotions is indeed partly mediated by novelty.

  Source: Mitas and Bastiaansen, Annals of Tourism Research

• What happens when you meet a holiday destination’s products at home?

  Yin, Poon and Su surveyed three hundred and forty-two tourists who had visited the heritage city of Lijiang in China. Coming across the destination’s products back home evokes autobiographical memory. The authors find that memory leads to pleasure and a positive mood, to higher destination attachment, and to greater intention to buy.

  Source: Yin et al., Tourism Management

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