You are here: Home page > Science > Psychology

Pavlov's dogs in his laboratory in 1904. Wellcome Collection.

10 great psychology experiments

Stare in the mirror and you'll find a strong sense of self staring back. Every one of us thinks we have a good idea who we are and what we're about—how we laugh and live and love, and all the complicated rest. But if you're a student of psychology—the fascinating science of human behaviour—you may well stare at your reflection with a wary eye. Because you'll know already that the ideas you have about yourself and other people can be very wide of the mark.

You might think you can learn a lot about human behaviour simply by observing yourself, but psychologists know that isn't really true. "Introspection" (thinking about yourself) has long been considered a suspect source of psychological research, even though one of the founding fathers of the science, William James, gained many important insights with its help. [1] Fortunately, there are thousands of rigorous experiments you can study that will do the job much more objectively and scientifically. And here's a quick selection of 10 of my favourites.

Photo: Ivan Pavlov trained dogs to associate the sound of a bell with the arrival of food in perhaps the most famous psychology experiment of all time. These are some of the dogs he worked with, pictured in his lab in 1904. Photo courtesy of the Wellcome Collection.

Sponsored links


  1. Are you really paying attention? (Simons and Chabris (1999))
  2. Are you trying too hard? (Aronson, 1966)
  3. Is the past a foreign country? (Loftus and Palmer, 1974)
  4. Do you cave in to peer pressure? Milgram, 1963, 1974)
  5. Are you a slave to pleasure? (Olds and Milner, 1954)
  6. Are you asleep at the wheel? (Libet, 1985)
  7. Why are you so attached? (Harlow et al, 1971)
  8. Are you as rational as you think? (Wason, 1966)
  9. How do you learn things? (Pavlov, 1890s)
  10. You're happier than you realize (Seligman, 1975)
  11. And so...

1: Are you really paying attention? (Simons & Chabris, 1999)

...our findings suggest that unexpected events are often overlooked...

Simons & Chabris, 1999

You can read a book or you can listen to the radio, but can you do both at once? Maybe you can listen to a soft-rock album you've heard hundreds of times before and simultaneously plod your way through an undemanding crime novel, but how about listening to a complex political debate while trying to revise for a politics exam? What about listening to a German radio station while reading a French novel?

What about mixing things up a bit more. You can iron your clothes while listening to the radio, no problem. But how about trying to follow (and visualize) the radio commentary on a football game while driving a highway you've never been along before? That's much more challenging because both things call on your brain's ability to process spatial information and one tends to interfere with the other. (There are very good reasons why it's unwise to use a cellphone while you're driving—and in some countries it's illegal.)

Generally speaking, we can do—and pay attention—to only so many things at once. That's no big surprise. However human attention works (and there are many theories about that), it's obviously not unlimited. What is surprising is how we pay attention to some things, in some situations, but not others. Psychologists have long studied something they call the cocktail-party effect. If you're at a noisy party, you can selectively switch your attention to any of the voices around you, just like tuning in a radio, while ignoring all the rest. Even more striking, if you're listening to one person and someone else happens to say your name, your ears will prick up and your attention will instantly switch to the other person instead. So your brain must be aware of much more than you think, even if it's not giving everything its full attention, all the time. [2]

Silverback gorilla eating bamboo.

Photo: Would you spot a gorilla if it were in plain sight? Picture by Richard Ruggiero courtesy of US Fish and Wildlife Service National Digital Library.

Sometimes, when we're really paying attention, we aren't easily distracted, even by drastic changes we ought to notice. A particularly striking demonstration of this comes from the work of Daniel Simons and Christopher Chabris (1999), who built on earlier work by the esteemed cognitive psychologist Ulric Neisser and colleagues. [3] Simons and Chabris made a video of people in black or white shirts throwing a basketball back and forth and asked viewers to count the number of passes made by the white-shirted players. You can watch it here.

Half the viewers failed to notice something else that happens at the same time (the gorilla-suited person wandering across the set)—an extraordinary example of something psychologists call inattentional blindness (in plain English: failure to see something you really should have spotted). A related phenomenon called change blindness explains why we generally fail to notice things like glaring continuity errors in movies: we don't expect to see them—and so we don't.

Whether experiments like "the invisible gorilla" allow us to conclude broader things about human nature is a moot point, but it's certainly fair to say (as Simons and Chabris argue) that they reveal "critically important limitations of our cognitive abilities." None of us are as smart as we like to think, but just because we fail and fall short that doesn't make us bad people; we'd do a lot better if we understood and recognized our shortcomings. [4]

2: Are you trying too hard? (Aronson, 1966)

No-one likes a smart-aleck, so the saying goes, but just how true is that? Even if you really hate someone who has everything—the good looks, the great house, the well-paid job—it tuns out that there are certain circumstances in which you'll like them a whole lot more: if they suddenly make a stupid mistake. This not-entirely-surprising bit of psychology mirrors everyday experience: we like our fellow humans slightly flawed, down-to-earth, and somewhat relatable. Known as the pratfall effect, it was famously demonstrated back in 1966 by social psychologist Elliot Aronson. [5]

...a superior person may be viewed as superhuman and, therefore, distant; a blunder tends to humanize him and, consequently, increases his attractiveness.

Aronson et al, 1966

Aronson made taped audio recordings of two very different people talking about themselves and answering 50 difficult questions, which were supposedly part of an interview for a college quiz team. One person was very superior, got almost all the questions right, and revealed (in passing) that they were generally excellent at what they did (an honors student, yearbook editor, and member of the college track team). The other person was much more mediocre, got many questions wrong, and revealed (in passing) that they were much more of a plodder (average grades in high school, proofreader of the yearbook, and failed to make the track team). In the experiment, "subjects" (that's what psychologists call the people who take part in their trials) had to listen to the recordings of the two people and rate them on various things, including their likeability. But there was a twist. In some of the taped interviews, an extra bit (the "pratfall") was added at the end where either the superior person or the mediocrity suddenly shouted "Oh my goodness I've spilled coffee all over my new suit", accompanied by the sounds of a clattering chair and general chaos (noises that were identically spliced onto both tapes).

Cartoon art of a spilled cup of coffee.

Artwork: Mistakes make you more likeable—if you're considered competent to begin with.

What Aronson found was that the superior person was rated more attractive with the pratfall at the end of their interview; the inferior person, less so. In other words, a pratfall can really work in your favor, but only if you're considered halfway competent to begin with; if not, it works against you. Knowingly or otherwise, smart celebrities and politicians often appear to take advantage of this to improve their popularity.

Sponsored links

3: Is the past a foreign country? (Loftus and Palmer, 1974)

Attention isn't the only thing that lets us down; memory is hugely infallible too—and it's one of the strangest and most complex things psychologists study. Can you remember where you were when the Twin Towers fell in 2001 or (if you're much older and willing to go back further) when JFK was shot in Dallas in 1963? You might remember a girl you were in kindergarten with 20 years ago, but perhaps you can't remember the guy you met last week, last night, or even 10 minutes ago. What about the so-called tip-of-the-tongue phenomenon where you're certain you know a word or fact or name, and you can even describe what it's like ("It's a really short word, maybe beginning with 'F'..."), but you can't bring it instantly to mind? [6] How about the madeleine effect, where the taste or smell or something suddenly sets off an incredibly powerful involuntary memory? What about déjà-vu: a jarring true-false memory—the strong sense something is very familiar when it can't possibly be? [7]

How about the curious split between short- and long-term memories or between "procedural memory" (knowing how to do things or follow instructions) and "declarative memory" (knowing facts), which breaks down further into "semantic memory" (general knowledge about things) and "episodic memory" (specific things that have happened to you). What about the many flavors of selective memory failure, such as seniors who can remember the name of a high-school sweetheart but can't recall their own name? Or sudden episodes of amnesia? Human memory is a massive—and massively complex—subject. And any comprehensive theory of it needs to be able to explain a lot.

...the questions asked subsequent to an event can cause a reconstruction in one's memory of that event..

Loftus & Palmer, 1974

Much of the time, poor memory is just a nuisance and we all have tricks for working around it—from slapping Post-It notes on the mirror to setting reminders on our phones. But there's one situation where poor memories can be a matter of life or death: in criminal investigation and court testimony. Suppose you give evidence in a trial based on events you think you remember that happened years ago—and suppose your evidence helps to convict a "murderer" who's subsequently sentenced to death. But what if your memory was quite wrong and the person was innocent?

One of the most famous studies of just how flawed our memories can be was made by psychologists Elizabeth Loftus and John Palmer in 1974. [8] After showing their subjects footage of a car accident, they tested their memories some time later by asking "About how fast were the cars going when they smashed into each other?" or using "collided," "bumped," "contacted," or "hit" in place of smashed. Those asked the first—leading—question reported higher speeds. Later, the subjects were asked if they'd seen any broken glass and those asked the leading question ("smashed") were much more likely to say "yes" even though there was no broken glass in the film. So our memories are much more fluid, far less fixed, than we suppose.

Illustration of Loftus and Palmer 1974 memory recall experiment.

Artwork: The words we use to probe our memories can affect the memories we think we have.

This classic experiment very powerfully illustrates the potential unreliability of eyewitness testimony in criminal investigations, but the work of Elizabeth Loftus on so-called "false memory syndrome" has had far-reaching impacts in provocative areas, such as people's alleged recollections of alien abduction, multiple personality disorder, and memories of childhood abuse. Ultimately, what it demonstrates is that memory is fallible and remembering is sometimes less of a mechanical activity (pulling a dusty book from long-neglected library shelf) than a creative and recreative one (rewriting the book partly or completely to compensate for the fact that the print has faded with time). [9]

4. Do you cave in to peer pressure? (Milgram, 1963)

Experiments like the three we've considered so far might cast an uncomfortable shadow, yet most of us are still convinced we're rational, reasonable people, most of the time. Asked to predict how we'd behave in any given situation, we'd be able to give a pretty good account of ourselves—or so you might think. Consider the question of whether you'd ever, under any circumstances, torture another human being and you'd probably be appalled at the prospect. "Of course not!" And yet, as Yale University's Stanley Milgram famously demonstrated in the 1960s and 1970s, you'd probably be mistaken. [10]

In the Milgram experiment, which is all about how we obey authority figures, you take a large number of experimental subjects and divide them into two groups called "learners" and "teachers". The "learners" have to learn pairs of words and the "teachers" (in a separate room but able to hear what the learners are saying and doing) have to assist by punishing them (giving them mild electric shocks) when they get their answers wrong. Meanwhile, an experimental supervisor hovers over the teachers stressing the importance of following their instructions. As the experiment progresses, the supervisor prompts the teachers to give higher and higher shocks that range from "Slight shock" all the way up to "Danger: Severe Shock, 450 volts," and even when the "learners" begin to pound on the wall and complain. As the shocks increase, and the subjects increasingly resist, the experimenters give stronger and stronger "prods" to go on: "The experiment requires that you continue," "It is absolutely essential that you continue," and "You have no other choice, you must go on."

A moving coil meter with a pointer dial showing amps

Artwork: The Milgram experiment: a shocking turn of events.

The twist in the experiment is that the "learners" (who are really ‘stooges' or accomplices of the experimenters) are not being shocked at all: the whole thing is a setup and no shocks are really being delivered. It's all a pretence. Despite failing to recognize this, the teachers happily go along with shocking the learners even when it should be obvious to them that what they're doing is quite wrong and, in all probability, very dangerous.

Milgram's experiments on obedience to authority have been widely discussed and offered as explanations for all kinds of things, from minor everyday cruelty to the appalling catalogue of repugnant human behavior witnessed during the Nazi Holocaust. Today, they're generally considered unethical because they're deceptive and could, potentially, damage the mental health of people taking part in them (a claim Milgram himself investigated and refuted). [26]

...the conflict stems from the opposition of two deeply ingrained behavior dispositions: first, the disposition not to harm other people, and second, the tendency to obey those whom we perceive to be legitimate authorities.

Milgram, 1963

Though Milgram's studies have not been repeated, related experiments have sought to shed more light on why people find themselves participating in quite disturbing forms of behavior. One explanation is that, like willing actors, we simply assume the roles we're given and play our parts well. In 1972, Stanford University's Philip Zimbardo set up an entire "pretend prison" and assigned his subjects roles as prisoners or guards. Quite quickly, the guards went beyond simple play acting and actually took on the roles of sadistic bullies, exposing the prisoners to all kinds of rough and degrading treatment, while the prisoners resigned themselves to their fate or took on the roles of rebels. [11] More recently, Zimbardo has argued that his work sheds light on atrocities such as the torture at the Abu Ghraib prison in 2004, when US army guards were found to have tortured and degraded Iraqi prisoners under their guard in truly shocking ways.

5. Are you a slave to pleasure? (Olds and Milner, 1954)

Why do we do the things we do? Why do we eat or drink, play football, watch TV... or do the legions of other things we feel compelled to do each day? How, when we take these sorts of behaviors to extremes, do we become addicted to things like drink and drugs, gambling or sex? Are they ordinary pleasures taken to extremes or something altogether different? Obsessions, compulsions, and addictive behaviors are complex and very difficult to treat, but what causes them... and how do we treat them?

Way back in 1954, a startling experiment by Canadian neuropsychologists James Olds and Peter Milner used tiny electric shocks to offer insight into pleasurable but highly addictive behavior. Electric shocks aren't always as painful and "shocking" as they turned out to be in the Milgram experiment; sometimes they provoke pleasure instead of pain. That much had been previously demonstrated by Tulane University's Robert Heath, though he didn't realize it at the time. While testing the idea that mental illnesses might be cured by "deep-brain stimulation" ("poking" the brain with electrodes), Heath found that schizophrenics reported pleasant feelings when he zapped their brains. (Much of Heath's work was intensely controversial, particularly a number of experiments he carried out later that attempted to prove he could cure homosexuality by brain stimulation. [12])

Cartoon art of a rat undergoing intracranial self stimulation, ICSS, in the Olds and Milner experiment.

Artwork: A rat will happily stimulate the "pleasure centre" in its brain.

Back to Olds and Milner. While systematically studying the effects of electricity on a rat's brain, they accidentally discovered that if they stimulated its septum (a tiny region deep in the core of the brain known as the limbic system), the animal would return for more. So they designed a follow-up experiment where they implanted an electrode in the rat's septum and wired it up to a foot pedal: if the rat pressed the pedal, it gave itself a shock. To their astonishment, the rat didn't just return once or twice: it kept coming back. The rats in this experiment "self-stimulated" up to 5000 times an hour until they finally collapsed from exhaustion. [13]

It appears that motivation, like sensation, has local centers in the brain.

James Olds, Scientific American, 1956.

The Olds and Milner ICSS (intracranial self-stimulation) experiment was widely interpreted as the discovery of a "pleasure center" in the brain, but we have to take that suggestion with quite a pinch of salt. It's fascinating, but also quite reductively depressing, to imagine that a lot of the things humans feel compelled to do each day—from work and eating to sport and sex—are motivated by nothing more than the need to scratch a deep neural itch: to repeatedly stimulate a "hungry" part of our brain. While it offers important insights into addictive behavior, the idea that all of our complex human pleasure-seeking stems from something so crudely behavioral—stimulus and reward—seems absurdly over-simple. It's fascinating to search for references to Olds and Milner's work and see it quoted in books with such titles as Your Money and Your Brain: How the New Science of Neuroeconomics Can Help Make You Rich. But it's quite a stretch from a rat pushing on a pedal to making arguments of that kind. [14]

Sponsored links

6: Are you asleep at the wheel? (Libet, 1983)

Being a conscious, active human being is a bit like driving a car: looking out through your eyes is like staring through a windshield, seeing (perceiving) things and responding to them, as they see and respond to you. Consciousness, in other words, feels like a "top-down" thing; like the driver of a car, we're always in control, willing the world to bend to our way, making things happen according to ideas our brains we devise beforehand. But how true is that really? If you are a driver, you'll know that much of what you do depends on a kind of mental "auto-pilot" or cruise control. As a practiced driver, you barely have to think about what you're doing at all—it's completely automatic.

We're only really aware of just how effort-full and attentive drivers need to be when we first start learning. We soon learn to do most of the things involved in driving without being consciously aware of them at all—and that's true of other things too, not just driving a car. Seen this way, driving seems impressive—but if you think again about the Simons and Chabris gorilla experiment, and consider its implications for sitting behind the wheel, you might want to take the bus in future.

Still, you might think, you're always, ultimately, in charge and in control: you're the driver, not the passenger, even if you are sometimes dozy at the wheel. And yet, a remarkable series of experiments by Benjamin Libet, in the 1980s, appeared to demonstrate something entirely different: far from consciously making things happen, sometimes we become conscious of what we've done after the fact. In Libet's experiments, he made people watch a clock and move their wrist when it reached a certain time. But their brain activity (which he was also monitoring) showed a peak a fraction of a second before their conscious decision to move, suggesting, at least in this case, that consciousness is the effect, not the cause. [15]

Many of our mental functions are carried out unconsciously, without conscious awareness.

Benjamin Libet, Mind Time, 2004, p.2.

On the face of it, Libet's work seems to have extraordinary implications for the study of consciousness. It's almost like we're zombies sitting at the wheel of a self-driving car. Is the whole idea of conscious free will just an illusion, an accidental artefact of knee-jerk behavior that happens much more automatically? You can certainly try to argue it that way, as many people have. On the other hand, it's important to remember that this is a highly constrained laboratory experiment and you can't automatically extrapolate from that to more general human behavior. (Apart from anything else, the methodology of Libet's experiments has been questioned. [16]) While you could try to argue that a complex decision (to buy a house or quit your job) is made unconsciously or subconsciously in whatever manner and we rationalize or become conscious of it after the fact, experiments like Libet's aren't offering evidence for that. Sometimes, it's too much of a stretch to argue from simple, highly contrived, very abstract laboratory experiments to bigger, bolder, and more general everyday behavior.

On the other hand, it's quite likely that some behavior that we believe to be consciously pre-determined is anything but, as William James (and, independently, Carl Lange) reasoned way back in the late 19th century. In a famous example James offered, we assume we run from a scary bear because we see the bear and feel afraid. But James believed the reasoning here is back to front: we see the bear, run, and only feel afraid because we find ourselves running from a bear! (How we arrive at emotions is a whole huge topic of its own. The James-Lange theory eventually spawned more developed theories by Walter Cannon and Philip Bard, who believed emotions and their causes happen simultaneously, and Stanley Shachter and Jerome Singer, who believe emotions stem both from our bodily reactions and how we think about them.) [17]

7: Why are you so attached? (Harlow et al, 1971)

Love is a wondrous state, deep, tender, and rewarding. Because of its intimate and personal nature it is regarded by some as an improper topic for experimental research.

Harry Harlow, 1958.

Fred the rhesus monkey after riding in the Little Joe spacecraft.

Artwork: Animals crave proper comfort, not just the simple "reduction" of "drives" like hunger. Photo courtesy of NASA and Wikimedia Commons.

There's an obvious evolutionary reason why we get attached to other people: one way or another, it improves our chances of surviving, mating, and passing on our genes to future generations. Attachment begins at birth, but our attachment to our mothers isn't motivated purely by a simple need for nourishment (through breastfeeding or whatever it might be). One of the most famous psychological experiments of all time demonstrated this back in the early 1970s.

The University of Wisconsin's Harry Harlow and his wife Margaret tested what happened when newborn baby monkeys were separated from their mothers and "raised," instead by crude, mechanical surrogates. In particular, Harlow looked at how the monkeys behaved toward two rival "mothers", one with a wooden head and a wire body that had a feeding bottle attached, and one made from soft, warm, comforting cloth. Perhaps surprisingly, the babies preferred the cloth mother. Even when they ventured over to the wire mother for food, they soon returned to the cloth mother for comfort and reassurance. [18]

The fascinating thing about this study is that it suggests the need for comfort is at least as important as the (more obviously fundamental) need for nourishment, so busting the cold, harsh claims of hard-wired behaviorists, who believed our attachment to our mothers was all about mechanistic "drive reduction," or knee-jerk stimulus and response. Ultimately, we love the loving—Harlow's "contact comfort"—and perhaps things like habits, routines, and traditions can all be interpreted in this light.

8: Are you as rational as you think? (Wason, 1966)

... I have concentrated mainly on the mistakes, assumptions, and stereotyped behavior which occur when people have to reason about abstract material. But... we seldom do reason about abstract material.

Peter Wason, 1966.

Like everyone else, you probably have your moments of wild, reckless abandon, but faced with the task of making a calm, rational judgment about something, how well do you think you'd do? It's not a question of what you know or how clever you are, but how well you can make a judgment or a decision.

Suppose, for example, you had to hire the best applicant for a job based on a pile of résumés. Or what if you had to find a new apartment by the end of the month and you had a limited selection to pick among. What if you were on the jury of a trial and had to sit through weeks or evidence to reach a verdict? How well do you think you'd do? Probably, given all the information, you feel you'd make a fair job of it: you have faith in your judgment. And yet, decades of research into human decision-making suggests you'll massively overestimate your own ability. Overconfident and under-informed, you'll jump to hasty conclusions, swayed by glaring biases you don't even notice. In the words of Daniel Kahneman, probably the world's leading expert on human rationality, your brain opts to think "fast" (reaches a quick and dirty decision) when sometimes it'd be better off thinking "slow" (reaching a more considered verdict). [25]

A classic demonstration of how poorly we think was devised by British psychologist Peter Wason in 1966. The experimenter puts a set of four white cards in front of you, each of which has a letter on one side and a number on the other. Then they tell you that if a card has a vowel on one side, it has an even number on the other side. Finally, they ask you which cards you need to turn over to verify if that statement is true. Suppose the cards show A, D, 4, and 7. The obvious answer, offered by most people, is A and 4 or just A. But the correct answer is actually A and 7. Once you've turned over A, it serves no purpose to turn over D or 4: turning over D tells us nothing, because it's not a vowel, while turning over 4 doesn't provide extra proof or disprove the statement. By turning over 7, however, you can potentially disprove the theory if you reveal a vowel on the other side of it. Wason's four-card test demonstrates what's known as "confirmation bias"—our failure to seek out evidence that contradicts things we believe. [19]

Peter Cathcart Wason's four-card selection test.

Artwork: Peter Wason's four-card selection test. If a card has a vowel on one side, it has an even number on the other. Which cards do you need to turn over to confirm this?

As with the other experiments here, you could extrapolate and argue that Wason's abstract reasoning test is echoed by bigger and wider failings we see in ourselves. Perhaps it goes some way to explaining things like online "echo chambers" and "filter bubbles", where we tend to watch, read, and listen to things that reinforce things we already believe—intellectual cloth mothers, you might call them—rather than challenging those comfortable beliefs or putting them to the test. But, again, a simple laboratory test is exactly what it is: a simple, laboratory test. And other, broader personal or social conclusions don't automatically follow on from it. (Indeed, you might recognize the tendency to argue that way as a confirmation bias all of its own.)

9: How do you learn things? (Pavlov, 1890s)

Learning might seem a very conscious and deliberate thing, especially if you hate the subject you're studying or merely sitting in school. What could be worse than "rote" learning your times table, practising French vocabulary, or revising for an exam? We also learn a lot of things less consciously—sometimes without any conscious effort at all. Animals (other than humans) don't sit in classrooms all day but they learn plenty of things. Even one of the simplest (a sea-slug called Aplysia californica) will learn to withdraw its syphon and gill if you give it an electric shock, as Eric Kandel and James Schwartz famously discovered. [20]

The animal must respond to changes in the environment in such a manner that its responsive activity is directed toward the preservation of its existence.

Ivan Pavlov, 1926.

So how does learning come about? At its most basic, it involves making connections or "associations" between things, something that was probed by Russian psychologist Ivan Pavlov in perhaps the most famous psychology experiment of all time. Pavlov looked at how dogs behave when he gave them food. Normally, he found dogs would salivate (a response) when he brought them a plate of food (a stimulus). We call this an unconditioned response (meaning default, normal, or just untrained): it's what the dogs do naturally. Now, with the food a distant doggy memory, Pavlov rang a bell (a neutral stimulus) and found it produced no response at all (the dogs didn't salivate). In the next phase of the experiment, he brought the dogs plates of food and rang a bell at the same time and found, again, that they salivated. So again, we have an unconditioned response, but this time to a pair of stimuli. Finally, after a period of this training, he tested what happened when he just rang the bell and, to his surprise, found that they salivated once again. In the jargon of psychology, we say the dogs had become "conditioned" to respond to the bell alone: they associated the bell with food and so responded by salivating. We call this a conditioned (trained or learned) response: the dogs have learned that the sound of the bell is generally linked to the appearance of food. [21]

Cartoon art of a  dog listening to a bell ringing and thinking 'dinner time'

Pavlov's work on conditioning was hugely influential—indeed, it was a key inspiration for the theory of behaviorism. Advanced by such luminaries as B.F. Skinner and J.B. Watson, this was the idea that animal behavior is largely a matter of stimulus and response and mental states—thinking, feeling, emoting, and reasoning—is irrelevant. But, as with all the other experiments here, it's a stretch to argue that we're all quasi-automated zombies raised in a kind of collective cloud of mind-control conditioning. It's true that we learn some things by simple, behavioural association, and animals like Aplysia may learn everything they know that way, but it doesn't follow that all animals learn everything by making endless daisy-chains of stimulus and response. [22]

10: You're happier than you realize (Seligman, 1975)

Money makes the world go round—or so goes the lyric of a famous song. But if you're American Martin Seligman, you'd probably think "happiness" was a better candidate for what powers the planet, or should. When I was studying psychology at college back in the mid-1980s, Professor Seligman came along to give a guest lecture—and it proved to be one of the most thought-provoking talks I would ever attend.

The time has finally arrived for a science that seeks to understand positive emotion, build strength and virtue, and provide guideposts for... 'the good life'.

Martin Seligman, Authentic Happiness, 2003.

Though now widely and popularly known for his work in a field he calls positive psychology, Seligman originally made his name researching mental illness and how people came to be depressed. Taking a leaf from Pavlov's book, his subjects were dogs. Rather than feeding them and ringing bells, he studied what happened when he gave dogs electric shocks and either offered them an opportunity to escape or restrained them in a harness so they couldn't. What he discovered was that dogs that couldn't avoid the shocks became demoralised and depressed—they "learned helpnessness"—and eventually didn't even try to avoid punishment, even when (once again) they were allowed to. [23]

You can easily construct a whole (behavioural) theory of mental illness on the basis of Seligman's learned helplessness experiments but, once again, there's much more to it than that. People don't become depressed purely because they're in impossible situations where problems seem (to use the terminology) "internal" (their own fault), "global" (affecting all aspects of their life), and "stable" (impossible to change). Many different factors—neurochemical, behavioral, cognitive, and social—feed into depression and, as a result, there are just as many forms of treatment.

What's really interesting about Seligman's work is what he did next. In the 1990s, he realized psychologists were obsessed with mental illness and negativity when, in his view, they should probably spend more time figuring out what makes people happy. So began his more recent quest to understand "positive psychology" and the things we can all do to make our lives feel more fulfilled. The key, in his view, is working out and playing to what he calls our "signature strengths" (things we're good at that we enjoy doing). His ideas, which trace back to those early experiments on learned helpless in hapless dogs, have proved hugely influential, prompting many psychologists to switch their attention to developing a useful, practical "science of happiness." [24]

And so...

What do these experiments tell us? We're simply not who we seem. On the debit side of the account, we don't really pay attention to the world around us, our memories are patchy, we make flawed judgements much of the time, we easily cave in to peer pressure, we're constantly distracted by simple pleasure seeking, and our overarching sense of being in control and determining events—our idea of conscious "free will"—is, at times, little more than illusion. But let's not be too harsh and hasty in judging ourselves. On the credit side, given the complexity of a modern world we haven't had time to evolve around, we don't make such a bad job of things. We might not be perfect, but usually we're acting in good faith and doing the best that we can. And, all things considered, we're often far happier and better adjusted than perhaps we realize.

Sponsored links

Find out more

On this website

Other websites


For older readers

For younger readers



  1.    See for example the classic discussion of consciousness in Chapter 9: The Stream of Thought in Principles of Psychology (Volume 1) by William James, Henry Holt, 1890.
  2.    Donald Broadbent carried out notable early work on "selective attention" as this is called. See, for example, The role of auditory localization in attention and memory span by D.E. Broadbent, J Exp Psychol, 1954, Volume 47 Number 3, pp.191–6.
  3.    [PDF] Gorillas in our midst: sustained inattentional blindness for dynamic events by Daniel J Simons, Christopher F Chabris, Perception, 1999, Volume 28, pp.1059–1074.
  4.    The Invisible Gorilla And Other Ways Our Intuition Deceives Us by Christopher Chabris and Daniel J. Simons. HarperCollins, 2010.
  5.    [PDF] The effect of a pratfall on increasing interpersonal attractiveness by Elliot Aronson, Ben Willerman, and Joanne Floyd, Psychon. Sci., 1966, Volume 4 Number 6,pp.227–228.
  6.    The 'tip of the tongue' phenomenon by Roger Brown and David McNeill, Journal of Verbal Learning and Verbal Behavior, Volume 5, Issue 4, August 1966, pp.325–337.
  7.    The Cognitive Neuropsychology of Déjà Vu by Chris Moulin, Psychology Press, 2017.
  8.    Reconstruction of automobile destruction: An example of the interaction between language and memory by Elizabeth Loftus and John Palmer, Journal of Verbal Learning & Verbal Behavior, Volume 13 Issue 5, pp.585–589.
  9.    "That Doesn't Mean It Really Happened": An Interview with Elizabeth Loftus by Carrie Poppy, The Sceptical Inquirer, September 8, 2016.
  10.    Behavioral study of obedience by Stanley Milgram, Journal of Abnormal and Social Psychology, 1963, Volume 67, pp.371–378.
  11.    A study of prisoners and guards in a simulated prison by Craig Haney, Curtis Banks, and Philip Zimbardo, Naval Research Review, 1973, Volume 30, pp.4–17.
  12.     Dr. Robert G. Heath: a controversial figure in the history of deep brain stimulation by Christen M. O'Neal et al, Neurosurg Focus 43 (3):E12, 2017. Serendipity and the Cerebral Localization of Pleasure by Alan A. Baumeister, Journal of the History of the Neurosciences, Basic and Clinical Perspectives, Volume 15, 2006. Issue 2. The 'gay cure' experiments that were written out of scientific history by Robert Colvile, Mosaic Science, 4 July 2016.
  13.    Positive reinforcement produced by electrical stimulation of septal area and other regions of rat brain by J. Olds and P. Millner, J Comp Physiol Psychol, 1954 Dec;47(6):419–27.
  14.    The Pleasure Areas by H.J. Campbell, Methuen, 1973.
  15.    Mind time: The temporal factor in consciousness by Benjamin Libet, Harvard University Press, 2004.
  16.    Exposing some holes in Libet's classic free will study by Christian Jarrett, BPS Research Digest, 2008.
  17.    For a decent overview, see the section "Theories of emotion" in 58: Emotion in Psychology by OpenStaxCollege.
  18.    The Nature of Love by Harry F. Harlow, American Psychologist, 13, pp.673–685. For a more general account, see Love at Goon Park: Harry Harlow and the Science of Affection by By Deborah Blum, Basic Books, 2002.
  19.    Reasoning by P.C. Wason, In Foss, Brian (ed.). New horizons in psychology. Penguin, 1966, p.145.
  20.    Eric Kandel and Aplysia californica: their role in the elucidation of mechanisms of memory and the study of psychotherapy by Michael Robertson and Garry Walter, Acta Neuropsychiatrica, Volume 22, Issue 4, August 2010, pp.195–196.
  21.    Conditioned reflexes; an investigation of the physiological activity of the cerebral cortex by I.P Pavlov. Dover, 1960.
  22.    Pavlov's dogs by Tim Tully, Current Biology, 2003, Volume 13, Issue 4, 18 February 2003, pp.R117–R119.
  23.    Learned Helplessness: Theory and Evidence by Steven Maier and Martin Seligman, Journal of Experimental Psychology: General, 1976, Volume 105, Number 1, pp3.–46.
  24.    Authentic Happiness by Martin Seligman, Nicholas Brealey, 2003.
  25.    Thinking Fast and Slow by Daniel Kahneman, Penguin, 2011.
  26.    Subject Reaction: The Neglected Factor in the Ethics of Experimentation by Stanley Milgram, The Hastings Center Report, Vol. 7, No. 5 (Oct., 1977), pp. 19–23.

Please do NOT copy our articles onto blogs and other websites

Articles from this website are registered at the US Copyright Office. Copying or otherwise using registered works without permission, removing this or other copyright notices, and/or infringing related rights could make you liable to severe civil or criminal penalties.

Text copyright © Chris Woodford 2021. All rights reserved. Full copyright notice and terms of use.

Follow us

Rate this page

Please rate or give feedback on this page and I will make a donation to WaterAid.

Tell your friends

If you've enjoyed this website, please kindly tell your friends about us on your favorite social sites.

Press CTRL + D to bookmark this page for later, or email the link to a friend.

Cite this page

Woodford, Chris. (2021) Great psychology experiments. Retrieved from [Accessed (Insert date here)]

Can't find what you want? Search our site below

More to explore on our website...

Back to top