How Psychology Has Changed Our Minds

How does the mind work? How can we explain consciousness, development, memory, language, rationality, emotions, racism, kindness, and hatred—the most important and intimate aspects of ourselves?

Solving these mysteries is the business of experimental psychology, the field I’ve devoted my life to. But not everyone is satisfied with how we’re doing our job. Some feel that psychology isn’t scientific enough in its approach and believe that the real answers are going to come from studies of the brain. Out with psychology; in with neuroscience! Others reject a scientific approach altogether and seek answers from mystics, self-help celebrities, and internet gurus.

This skepticism is understandable. Our field is going through a replication crisis, as many of our best-known findings have failed to hold up. And, like any field, progress in psychology can be slow, and the answers we give are often tentative and qualified.

But I am bullish about psychology. The field has come up with some striking findings that shatter common-sense conceptions about how the mind works. I’ll tell you about four of them.

More From TIME

1. Babies know more than we could have imagined

The idea that we start off with empty heads was an accepted view by many scholars. In 1890, William James described the mental life of a baby as “a blooming, buzzing confusion.” A century earlier, Jean-Jacques Rousseau made this point in harsher terms, saying that if a child were born in an adult body, “such a child-man would be a perfect idiot”

Maybe you believe this too—babies sure don’t seem very smart. But psychologists have employed clever methods to capitalize on the few things babies are good at, such as sucking on a pacifier and moving their eyes. This might not sound like much, but in the hands of clever researchers, these behaviours can reveal the secrets of the infant soul.

We have discovered an inborn system for reasoning about objects, one present in babies as young as researchers are able to test (and also present in species other than humans, such as newborn baby chicks). Babies know, for instance, that objects that go out of sight continue to exist.

We know that, early on, babies also have some understanding of people. Imagine a table with two different objects on it, and a hand reaching for one of them. Then the objects switch places. Adults know that hands are attached to people, and people have goals, and a reasonable goal for a person is to reach for a particular object, not to go to a specific location. Six-month-olds have the same expectation. They are even capable of rudimentary moral judgments. If you show them a character who helps someone and another character who gets in that person’s way, six-month-olds prefer the helper. When you look into the big eyes of a baby, there’s someone smart looking back.

2. Memory is not to be trusted

Some people believe that we make perfect recordings of the world.  Any memory can be recovered if we work hard enough at it, whether through self-reflection, hypnotic regression, or probing by a patient psychiatrist.

None of this is true. Memory is fuzzy and vague; much of what we experience never gets stored in our brains, and much of what is stored gets distorted over time. When we try to remember something, it’s not like a computer retrieving information; it’s more of a storytelling process—an on-the-fly reconstruction.

One way we know this is through studies where psychologists implant false memories in their subjects. Sometimes this is subtle—showing people a scene and later asking them “did you see children getting on the school bus?” makes them more likely, later, to remember a school bus, even if it wasn’t there. Sometimes it’s more heavy-duty. In one study, psychologists asked college students’ family members for information about events from their childhoods and interviewed students about their memories. The twist is that for each interview, one event—being lost in a shopping mall, nearly drowning, spilling punch on a bride’s parents during a wedding, being attacked by a vicious animal—was entirely fabricated by the researchers. Despite this, many of the subjects came to remember these false events as actually occurring.

This research has led to a revolution in the law. Memory research has helped us appreciate that police interrogations that are intended to retrieve memories can instead shape and create them. On a more personal level, it’s worth knowing—maybe when you’re arguing with your partner!—that you can be perfectly confident in a memory and yet entirely mistaken about it.

3. Consciousness is surprisingly limited

When you close your eyes and open them again, would you notice if everything changed?

One of the great discoveries of cognitive psychology finds that only a small fraction of sensory experience makes its way in; everything else is ignored and lost forever. In one famous study, reported in a paper titled “Gorillas in Our Midst,” subjects are shown a video in which people in white shirts and black shirts are standing in a hallway passing basketballs back and forth. The subjects’ task is to focus on the white shirts and count the passes they make. People don’t find this hard, but it does take all their attention. Here’s the twist: In the middle of the video someone dressed as a gorilla walks onto the scene, stops in the middle and pounds his chest, then walks off. About half of the subjects don’t see this at all, though the presence of the gorilla is screamingly obvious for anyone who is not told to focus on the passing of the basketballs.

We tend to be ignorant of these limitations. It feels like we are conscious of the world, not just a small sliver of it. It feels like we can attend to multiple things at the same time, rather than being forced to move our attention back and forth. Our limitations are harmless enough if we are listening to a podcast while mowing the lawn. But they can be fatal in cases where something needs our full attention, such as driving. Talking on the phone, even using a hands-free device, slows our reaction time on the road to an extent that is roughly the same as being legally intoxicated.

4. Insights from the new science of happiness

A few decades ago, a group of psychologists worried that there has been too much focus on the negative. We haven’t done enough research into what goes into a pleasant and meaningful and satisfying life. A new movement, known as positive psychology, emerged to change all this. And now we have a lot of data, some from studies of millions of people, that help us appreciate the conditions for human flourishing.

Some of the findings are common sense. Money does lead to happiness, both at the level of individuals (richer people are happier) and countries (citizens of richer countries are happier)—though there are diminishing returns once the numbers get high enough. Social connections are even more important; one study, published in the journal Science, found that being lonely has a worse effect on health than obesity and smoking.

Other findings are more surprising. Research into aging and happiness find that for many people, the 50s are the saddest period of their lives, and then happiness starts to rise—for many, the eighties are the happiest times of their lives.  Who would have thought?

Happiness researchers have also discovered a paradox. There is a strong relationship between thinking a lot about happiness and … being sad. The moral here is: don’t spend too much time pouring over the happiness research!

There are so many other findings that could have made the list, and there will be more in the future. I’m most excited by debates over how well deep learning (how ChatGPT and other AIs work) can work as a model for human thinking, as well in recent developments in clinical psychology, including trials of mind-altering drugs such as ketamine and psylocibin, as treatments for depression and anxiety. These are exciting times to be a psychologist.