The Neuroscience of You
How Every Brain Is Different and How to Understand Yours
By Chantel Prat
Category: Psychology | Reading Duration: 18 min | Rating: 4.6/5 (809 ratings)
About the Book
The Neuroscience of You (2022) is an accessible primer to the human brain that explores how our individual quirks arise. Packed with practical tests and cutting-edge insights into why you think differently from others, it invites you to take a closer look at your brain and discover what makes it unique– and how to understand others and their quirks better.
Who Should Read This?
- Fans of neuroscience
- Those eager to learn about the specifics of brain functions
- Anyone curious about where individuality comes from
What’s in it for me? Discover how every brain is wired differently, and what this means for our behavior.
What makes us who we are?Everyone’s brain is structurally different– even the brains of identical twins conjoined at birth– and these structural differences matter. They shape how we see the world, and how we decide to operate in it. It affects whether we’re thrill seekers, how good we are at picking up languages, and even how we feel about karaoke. Despite their importance, the biological differences in our brains are rarely discussed. The field of neuroscience has been dominated by a one-size-fits-all approach for over a century. What we know about brains is usually informed by scientists who focus on how brains work on average, glossing over our individual differences. But this is a missed opportunity to understand ourselves, other people, and the brain more deeply.In this Blink, we’ll draw upon the cutting-edge insights of neuroscientist Chantel Prat, who researches how brains differ, and why small differences in our brains can cause big differences in our characters. You’ll discover how our brain’s lopsidedness affects how we approach problems, that our neurochemical cocktail determines how extraverted we are, and why it is that brains see colors differently. Ready? Let’s zoom into the inner workings of your brain and discover what makes you you.
Chapter 1: Brains that specialize in different functions interpret the world in varied ways.
Have you ever heard of The Knowledge?It’s the test required to be a taxi driver in London, and it’s one of the most famously difficult exams in the world. The test demands that you memorize London’s 20,000 windy streets and every business or landmark on each street. The test weeds out over half the people who take it— even if they’ve studied for it for years. It’s a truly herculean task!A landmark study in 2000 showed that drivers who successfully acquired The Knowledge of London’s streets have a larger-than-average tail of the hippocampus, the region of the brain that is associated with spatial memory. In other words, by repeatedly asking their brains to perform specific tasks– like memorizing London, a complex and disorganized system– the taxi drivers actually changed their brains’ physicality. Studying the cabbies’ brains led to another important discovery: though the tail of the hippocampus grows as they study for The Knowledge, the top of the hippocampus was actually smaller than average. Researchers then compared the brains of the taxi drivers to those operating in a similar environment: London bus drivers. They found that the taxi drivers had superior spatial memory to the bus drivers, but they had worse short-term memory and visual memory.What this head-to-head comparison shows us is that there’s a cost to specialization. Certain enhancements of one type of memory will crowd out brain regions that are performing other jobs. After all, there’s only so much room in any given brain! Now, it’s not just that specialization leads your brain to perform certain functions better at the expense of other functions. What ends up happening is that brains that specialize in different functions end up interpreting the world in different ways– which is what Dr. Prat’s book is all about.To begin to break down why that is, it’s helpful to think of our brains as finite information-processing machines operating in an essentially infinite environment. And in order to do its job effectively of keeping you alive in the big bad universe, your brain has to process the infinite environment into manageable pieces. In other words, it’s constantly filtering, and filling in the missing blanks with what it thinks is probably happening. It’s a bit like being given a stack of blurry photographs and being asked to make a movie with them. You have to decide which images are important and how to connect the dots to make a coherent video when there is missing information. And because brains are structurally different and shaped by different experiences, they’ll process information in varying ways. One brain will deal with its inherent limitations differently than another, by relying on the computations and functions at which it’s more adept in order to figure out what is happening. And this is a major factor in why we have so much variation in worldviews and behaviors!Now let’s take a closer look at how specific features of our brains will lead us to operate in varied ways in the real world. We’ll start with how the degree of our brain’s lopsidedness affects how we solve problems.
Chapter 2: Your brain’s lopsidedness affects how you process information.
Imagine the human brain for a moment. It’s about three pounds, and it looks something like a large walnut, with two largely independent hemispheres connected at the core. Now, this isn’t a very unique brain design. We can find divided brains throughout the animal kingdom, within all vertebrate animals.What’s peculiar to humans is that our brains are, on average, remarkably lopsided, with the left hemisphere tending to be larger. This cerebral asymmetry is actually what makes us particularly good at complex speech and analytical tasks. But some of us are more lopsided than others, and it’s these variations of degree that make a difference in how we approach problem solving. You might have heard analytical people described as left-brained, and creative people are considered right-brained. There’s a grain of truth to this, but it’s a bit more complicated than that. In reality, your strengths aren’t determined by which hemisphere is the “boss” of your brain— rather, it’s the degree to which your brain is lopsided that affects what types of mental computations you rely on more than others when faced with ambiguous information. This structural difference is a major reason why humans can have widely different interpretations of the same input. It’s true that the left hemisphere is, in most people, optimally structured for analytical processes— it accomplishes its various functions with a “divide and conquer” approach by executing specialized computations that don’t interact with one another. If someone has a highly lopsided brain, they tend to rely more on computations associated with the left hemisphere. What this looks like in everyday life is that lopsided-brained people tend to solve problems by focusing on its specific details. It’s a bit like building a picture of a forest by processing one tree at a time.In contrast, the right hemisphere is structured in a way that makes it better equipped to integrate different types of information into a coherent whole. So it builds a picture of a forest with a big-picture approach– it looks at something vertical and brown and says “Hmm, I know I’m in a forest, so this is most likely a tree.” In other words, it relies on wider context to make inferences about a given situation.Now, all brains have forest and tree capabilities. Both approaches are vital to the many complex tasks we humans perform on a daily basis, so we’ve gotten really good at both over our evolutionary history. But if your brain is more lopsided, you’re more likely to focus on specific details to solve problems, and people with more balanced brains tend to consider the wider context over the specific details. So, how lopsided is your brain? There are a few quick-and-dirty ways of approaching this question.First, consider these everyday tasks: Brushing your teeth. Writing with a pen. Eating with a spoon. Opening a box. Holding the top of a broom handle as you sweep.Now ask yourself if you would perform these tasks only with your dominant hand. Or would you feel comfortable switching between hands for at least some of these tasks?How about looking into a microscope or the viewfinder of a camera: do you have an eye that you prefer?If you could only imagine performing these tasks with your dominant hand and your dominant eye, then your brain is likely more lopsided. If you’re more comfortable switching between right and left hands, and right and left eye, your brain is likely more balanced.In the next section, we’ll turn our attention to the smallest parts of our brain features– the neurotransmitters, which are the chemicals that your neurons need to communicate– and dive into why such tiny parts can have a huge impact on us.
Chapter 3: Your brain is a unique neural cocktail, and its ingredients shape your personality.
Ah, coffee. What would life be without it?There’s a reason caffeine is the most popular drug in the world. In fact, a life without coffee would be a life with less pleasure! That’s because caffeine increases the availability of the neurotransmitter dopamine, the chemical that the pleasure circuits in your brain use to communicate. Now consider this: what if someone else’s baseline levels of dopamine exceed the boost you get from your morning shot of espresso? In other words, what if they feel generally more pleasure than you? Or the other way around: someone else’s highest feelings of pleasure might be how you feel before you’ve had your morning cup of joe.Anyone who’s experienced depression knows well how a brain with a lower level of feel-good chemicals can have a fundamentally different experience of the world than someone with higher levels. But dopamine levels profoundly affect our personalities and behaviors, whether we have depression or not. Dopamine circuits play a big role in decision-making because they’re nudging you through the world in a way that will bring about the most amount of pleasure possible. In effect, differing levels of dopamine from brain to brain will affect how strongly one is motivated toward different behaviors. One key way this plays out in our personalities is in how introverted or extraverted we are. Extraverted people are those who tend to “turn outward” and seek mental stimulation from external stimuli. Introverted people, on the other hand, often prefer their own thoughts and feelings to the outer world and tend to “turn inward.” You probably have a good idea of where you fall on this continuum. Converging research demonstrates that dopamine is at least partially responsible for our introversion or extraversion because of how dopamine rewards our brains. It turns out that when unexpected rewards happen to extraverts, their brains actually release more dopamine than in their introverted counterparts. Another way of putting it is: if life were a video game, then extraverts get more pleasure points every time they’re positively surprised. So this makes them extra motivated to seek out outside stimulation. So what does different susceptibility to dopamine look like in practice? Well, extraverts consistently rate themselves as more optimistic and happier than introverts. They’re also more likely to seek novelty and are more motivated to learn– and it’s no wonder, since external stimulation brings them extra pleasure.You may be wondering if it’s simply better to be an extravert. It’s true that introversion has been linked to anhedonia and depression. But, despite extraverts experiencing more pleasure, there are also downsides to this design feature. For one thing, additional susceptibility to dopamine makes it more difficult for extraverts to override temptation for things that are bad for us. Extraversion has been linked with obesity and addiction, for example. Now, let’s zoom back out for a moment and give your right hemisphere some big-picture context to consider. Dopamine is just one neurotransmitter of hundreds that drive the way you think, feel, and behave. Others include oxytocin, serotonin, and cortisol– and they’re all interacting with each other in a delicate balance. If varied levels of just one of these can affect your experience of the world so profoundly, it’s no wonder that the unique mixology of our neural cocktails creates such starkly different individuals!In the last two sections, we discussed how the brain features of lopsidedness and neurochemistry affect our behavior. Now, in the final section, we’ll explore how our life experiences shape our brains. We’ll discover how our past life creates the lens through which we see the present.
Chapter 4: Experience creates lenses through which we filter the world.
Who here remembers The Dress? No, not one worn by Marilyn Monroe, Princess Diana, or Monica Lewinsky.The Dress was a viral image that took the internet by storm in 2015. It’s a photograph of a striped dress that about half the population saw as blue and black, and the other half as white and gold. If you don’t know what I’m talking about, look up “The Dress” on Wikipedia. What colors do you see?Dr. Prat posits that The Dress went viral because it’s a very stark example of how our brains create alternate versions of reality. It’s fascinating to discover that even something as basic as the colors of a static image are open to interpretation!Even when told that the “actual” colors of The Dress in the photograph are blue and black, the people who see it as white and gold usually cannot see its true colors unless the lighting of the image is altered. As it turns out, the reason for this is at least partially due to our life experiences.The lighting in the viral image is ambiguous, so our brain relies on a shortcut to make sense of the incomplete data it’s faced with. This results in brains with different past experiences making different assumptions about the source of the light, which in turn affects how the brain perceives the colors of The Dress. If you’re seeing The Dress as white and gold, your brain is assuming that The Dress is in shadow and that the light is coming from behind. Research suggests that this is likely because you’re more familiar with natural lighting and that you’re an early riser. On the other hand, if you’re seeing The Dress as black and blue, your brain is assuming the lighting is coming from the front, probably through an artificial source. This perception correlates with people who tend to be night owls and have more experience with artificial lighting.Our brains are shaped so profoundly by previous experience due to a process called Hebbian learning. In a nutshell, the theory of Hebbian learning states that when our brains learn something new, neurons are activated and connected with other neurons. At first these connections are weak, but they grow stronger every time the experience repeats, so the process becomes more intuitive. It’s what people mean when they say “neurons that fire together, wire together.”Hebbian learning influences your brain over your lifespan and allows you to make shortcuts that are critical to your survival, so that you can make split-second inferences without processing an event as new every time. That would be time-consuming and exhausting. Hebbian learning is also at play when we learn skills like driving, that are difficult at first but become more and more automatic over time. But experience-based shortcuts can also lead us into some problematic territories that can be difficult to correct, such as biases. A telling example of this has been demonstrated many times: people are more likely to assume an ambiguous object is a gun when presented next to a Black person’s face than a white person’s face. This mental shortcut arises without a correlation to someone’s actual experiences with Black people and guns, especially considering that gun ownership is common across many demographics in the United States.So where do these biased mental shortcuts come from, if not from direct experience? Well, if your brain does not have direct experiences with something in real life– or some people– then it’s more likely that its database entry on a given topic is based on what it sees on television or in fictitious depictions. In this way, systemic biases can quite literally shape the way your brain perceives the world. Changing your brain’s perception isn’t as simple as just becoming aware of your biases. Remember, those who see The Dress as white and gold can’t flip their perception just because they discover it’s actually blue and black. Instead, correcting your brain’s shortcuts is more likely to occur if you expose yourself to diverse and real-world experiences, and become more intentional about the types of narratives you feed your mind.
Final summary
You’ve just listened to our Blink to The Neuroscience of You, by Chantel Prat.The key message in this Blink is: Small differences in our brains that we’re either born with or adapt to create big differences in our thoughts, behaviors, emotions, and abilities. Just consider that the DNA blueprints that underlie chimp and human brains differ by only 5 percent– but that 5% allows humans to send complex messages in split-seconds across the globe, while the chimp’s day is occupied with finding food and picking nits. Or on a much subtler level, think about how differently you feel in the morning versus in the evening. The changes in neurochemical signaling throughout the course of just twelve hours can cause a significant difference in how you’re experiencing the world. The point is: our differences matter, and a neuroscience that looks into them can provide a window into the self. Thanks so much for listening. And if you can, please leave us a rating. You can find the “rate it’ button on your screen right now – we always appreciate your feedback. See you in the next Blink.
About the Author
Chantel Prat, PhD is a professor of psychology, neuroscience, and linguistics at the University of Washington. She is a public speaker at events like The World Science Fair, and she is featured in the documentary I Am Human. Her publications have been profiled in Scientific American, Psychology Today, NPR, and more.