Top Ten Myths about YOUR Brain

True confessions:  At one time we too believed some of the myths.  (This is so well-written we were left speech-less with the exceptions of some asides which we always put in red italics so we are not sued)

Brain myths

Myth 1. We only use a small percentage of our brain.

“Repeated in pop culture for a century, the notion that humans only use 10 percent of our brains is false. Scans have shown that much, if not all, of the brain is engaged even during simple tasks.”

Myth 2. “Flashbulb memories” are precise, detailed and persistent. 

“We all have memories that feel as vivid and accurate as a snapshot, usually of some shocking, dramatic event—the assassination of President Kennedy, the explosion of the space shuttle Challenger, the attacks of September 11, 2001. People remember exactly where they were, what they were doing, who they were with, what they saw or heard. But several clever experiments have tested people’s memory immediately after a tragedy and again several months or years later. The test subjects tend to be confident that their memories are accurate and say the flashbulb memories are more vivid than other memories. Vivid they may be, but these memories decay over time just as other memories do. People forget important details and add incorrect ones, with no awareness that they’re recreating a muddled scene in their minds rather than calling up a perfect, photographic reproduction.”

Myth 3. It’s all downhill after 40 (Good to know that as our bodies slide downhill our brains are still firm and appropriately wrinkled)

“It’s true, some cognitive skills do decline as you get older. Children are better at learning new languages than adults—and never play a game of concentration against a 10-year-old unless you’re prepared to be humiliated. Young adults are faster than older adults to judge whether two objects are the same or different; they can more easily memorize a list of random words, and they are faster to count backward by sevens.”

“But plenty of mental skills actually improve with age:

  • Vocabulary – older people know more words and understand subtle linguistic distinctions.
  • Given a biographical sketch of a stranger, they’re better judges of character.
  • They score higher on tests of social wisdom, such as how to settle a conflict.
  • People get better and better over time at regulating their own emotions and finding meaning in their lives.

Myth 4. We have five senses. 

sketch-1641261225422

“Sight, smell, hearing, taste and touch are the big ones. But we have many other ways of sensing the world and our place in it. Proprioception is a sense of how our bodies are positioned. Nociception is a sense of pain. We also have a sense of balance—the inner ear is to this sense as the eye is to vision—as well as a sense of body temperature, acceleration and the passage of time.”

“Compared with other species, though, humans are missing out. Bats and dolphins use sonar to find prey; some birds and insects see ultraviolet light; snakes detect the heat of warmblooded prey; rats, cats, seals and other whiskered creatures use their “vibrissae” to judge spatial relations or detect movements; sharks sense electrical fields in the water; birds, turtles and even bacteria orient to the earth’s magnetic field lines.”

Myth 5. Brains are like computers. 

“We speak of the brain’s processing speed, its storage capacity, its parallel circuits, inputs and outputs. The metaphor fails at pretty much every level:

  • The brain doesn’t have a set memory capacity that is waiting to be filled up
  • It doesn’t perform computations in the way a computer does
  • Basic visual perception isn’t a passive receiving of inputs because we actively interpret, anticipate and pay attention to different elements of the visual world.

“There’s a long history of likening the brain to whatever technology is the most advanced, impressive and vaguely mysterious.”

  • Descartes compared the brain to a hydraulic machine.
  • Freud likened emotions to pressure building up in a steam engine.
  • The brain later resembled a telephone switchboard and then an electrical circuit before evolving into a computer;
  • lately it’s turning into a Web browser or the Internet.

These metaphors linger in clichés: emotions put the brain “under pressure” and some behaviors are thought to be “hard-wired.”

Myth 6. The brain is hard-wired. (This is not that same as being hard-headed, which is not a myth)

“This is one of the most enduring legacies of the old “brains are electrical circuits” metaphor. There’s some truth to it, as with many metaphors: the brain is organized in a standard way, with certain bits specialized to take on certain tasks, and those bits are connected along predictable neural pathways (sort of like wires) and communicate in part by releasing ions (pulses of electricity).”

“But one of the biggest discoveries in neuroscience in the past few decades is that the brain is remarkably plastic. In blind people, parts of the brain that normally process sight are instead devoted to hearing. Someone practicing a new skill, like learning to play the violin, “rewires” parts of the brain that are responsible for fine motor control. People with brain injuries can recruit other parts of the brain to compensate for the lost tissue.”

(Did you read  the true story,The Pulling, Climbing, Falling Down Tale of Maui and His Back Legs about how Peggy’s cat Maui rewired his brain so he could walk after his back legs were paralized?  It’s a FREE PDF on our January Knewsletter – email us if you didn’t get a copy)

Myth 7. A conk on the head can cause amnesia. 

sketch-1641261364424

“Next to babies switched at birth, this is a favorite trope of soap operas: Someone is in a tragic accident and wakes up in the hospital unable to recognize loved ones or remember his or her own name or history. (The only cure for this form of amnesia, of course, is another conk on the head.)”

“In the real world, there are two main forms of amnesia: anterograde (the inability to form new memories) and retrograde (the inability to recall past events). Science’s most famous amnesia patient, H.M., was unable to remember anything that happened after a 1953 surgery that removed most of his hippocampus. He remembered earlier events, however, and was able to learn new skills and vocabulary, showing that encoding “episodic” memories of new experiences relies on different brain regions than other types of learning and memory do. Retrograde amnesia can be caused by Alzheimer’s disease, traumatic brain injury (ask an NFL player), thiamine deficiency or other insults. But a brain injury doesn’t selectively impair autobiographical memory—much less bring it back.”

Myth 8. We know what will make us happy. (If only this WERE true . . .)

“In some cases we haven’t a clue. We routinely overestimate how happy something will make us, whether it’s a birthday, free pizza, a new car, a victory for our favorite sports team or political candidate, winning the lottery or raising children. Money does make people happier, but only to a point—poor people are less happy than the middle class, but the middle class are just as happy as the rich. We overestimate the pleasures of solitude and leisure and underestimate how much happiness we get from social relationships.”

“On the flip side, the things we dread don’t make us as unhappy as expected. Monday mornings aren’t as unpleasant as people predict. Seemingly unendurable tragedies—paralysis, the death of a loved one—cause grief and despair, but the unhappiness doesn’t last as long as people think it will. People are remarkably resilient.”

Myth 9. We see the world as it is. 

“We are not passive recipients of external information that enters our brain through our sensory organs. Instead, we actively search for patterns (like a Dalmatian dog that suddenly appears in a field of black and white dots), turn ambiguous scenes into ones that fit our expectations (it’s a vase; it’s a face) and completely miss details we aren’t expecting. In one famous psychology experiment, about half of all viewers told to count the number of times a group of people pass a basketball do not notice that a guy in a gorilla suit is hulking around among the ball-throwers.”

“We have a limited ability to pay attention (which is why talking on a cellphone while driving can be as dangerous as drunk driving), and plenty of biases about what we expect or want to see. Our perception of the world isn’t just “bottom-up”—built of objective observations layered together in a logical way. It’s “top-down,” driven by expectations and interpretations.”

10. Men are from Mars, women are from Venus. (No comment)

“Some of the sloppiest, shoddiest, most biased, least reproducible, worst designed and most overinterpreted research in the history of science purports to provide biological explanations for differences between men and women. Eminent neuroscientists once claimed that head size, spinal ganglia or brain stem structures were responsible for women’s inability to think creatively, vote logically or practice medicine. Today the theories are a bit more sophisticated: men supposedly have more specialized brain hemispheres, women more elaborate emotion circuits. Though there are some differences (minor and uncorrelated with any particular ability) between male and female brains, the main problem with looking for correlations with behavior is that sex differences in cognition are massively exaggerated.”

“Women are thought to outperform men on tests of empathy. They do—unless test subjects are told that men are particularly good at the test, in which case men perform as well as or better than women. The same pattern holds in reverse for tests of spatial reasoning. Whenever stereotypes are brought to mind, even by something as simple as asking test subjects to check a box next to their gender, sex differences are exaggerated. Women college students told that a test is something women usually do poorly on, do poorly. Women college students told that a test is something college students usually do well on, do well. Across countries—and across time—the more prevalent the belief is that men are better than women in math, the greater the difference in girls’ and boys’ math scores. And that’s not because girls in Iceland have more specialized brain hemispheres than do girls in Italy.”

“Certain sex differences are enormously important to us when we’re looking for a mate, but when it comes to most of what our brains do most of the time—perceive the world, direct attention, learn new skills, encode memories, communicate (no, women don’t speak more than men do), judge other people’s emotions (no, men aren’t inept at this)—men and women have almost entirely overlapping and fully Earth-bound abilities.”

 https://www.smithsonianmag.com/science-nature/top-ten-myths-about-the-brain-178357288/#KSSZgGZ7vPRdJWWq.99

7 (and a half) myths about your brain

“In the 19th Century, serious physicists believed that the Universe was filled with an imaginary substance called luminiferous ether.”

“Doctors believed that illnesses were caused by smelly vapours called miasmas. Both of these scientific myths survived for over one hundred years until, eventually, they were vanquished by evidence.”

“The field of neuroscience likewise has a stable full of myths about the brain that have slowly been eroded by accumulating data. Some survive today, mainly in the media and some popular science books and articles. Neuroscientist David Linden refers to them as “neurobullsh*t.” They are maintained not by evidence, but by repetition and belief.

ccc

Here are a few favorites:”

Myth #1: You have a lizard in your head

“Have you ever heard that your smouldering passions lie deep in ancient parts of your brain, which you supposedly inherited from prehistoric reptiles? Or that your “rational brain”, which sits atop your “lizard brain”, tries to cage your desires to keep them in check? This intuitive story of your inner reptile, safely wrapped in a cloak of rationality, seemingly explains what it means to be a moral, healthy person. It is also one of the most successful errors in all of science. To quote the neuroscientist Barbara Finlay, “Your brain is not a lizard in drag.”’

“The idea that your mind is a battleground between passion and reason goes all the way back to Ancient Greece. It became a popular lens for charting brain evolution in the mid-20th Century, as scientists tried to understand brain function by comparing human brains to other animal brains by eye. More recent neuroscience clearly shows, however, that brains don’t evolve in layers like adding icing to an already-baked cake. Instead, the brains of all mammals, and possibly all vertebrates, follow a single manufacturing plan. The only animal with a lizard brain is a lizard.”

c

Myth #2: The left side of your brain is logical and the right side is creative

“In general, no part of your brain is exclusively dedicated to artistic endeavours, mathematical reasoning, or any other psychological function. Pretty much every action you take and every experience you have is computed by neurons distributed across your whole brain.”

“One part of your brain — the cerebral cortex — indeed consists of two halves or hemispheres, but both are intricately connected to many subcortical bits that make up the rest of your brain. So it’s simply not the case that some neurons in the left hemisphere create a computer engineer and some on the right create a poet. A few functions seem to take place mostly in one hemisphere, such as language ability on the left, but this lateralisation develops gradually and in most, but not every, individual.”

Myth #3: Cortisol is a stress hormone, and serotonin is a happiness hormone

“It’s a common belief that your brain screams “ I’m stressed ” by having cortisol gush through your arteries, and neurons shower serotonin on each other to create a joyful, happy feeling. In reality, no hormone has just one specific psychological purpose (that we know of), and all the chemicals that help to create your mind work in concert.

“Cortisol, for example, boosts the amount of glucose in your bloodstream to provide a quick burst of energy for your cells when your brain predicts the need, whether you feel stressed or not. Your brain tells your adrenal glands to let loose some cortisol right before you exercise or awaken in the morning to drag yourself out of bed. Cortisol may be released during stress but it is not a “stress hormone.”’

“Likewise, serotonin is not a “happiness hormone.” It has many functions. In your body, for example, serotonin regulates how much fat is made. In your brain, serotonin helps keep track of the energy you spend and gain. It allows you to spend energy even if there’s no immediate reward for doing so, which enables you to explore, forage, and be curious. Serotonin also helps other neurons pass information back and forth as they create your thoughts, feelings, perceptions, and actions.”

Myth #4: Your eyes see, your ears hear, and your skin feels

“Think about the last time you washed your face. Your skin felt the soothing, warm water. Or did it? Your skin actually has no sensors for wetness. So what’s happening here? Your brain is secretly combining several sources of information, including touch, temperature, and your knowledge from past experience, to construct a feeling of being wet.”

“All of your sensations, in fact, are computed in your brain, not simply detected in the world by your sense organs. You don’t see with your eyes — you see with your brain, based on a combination of what’s in your head and the sense data coming from your retinas.”

“Likewise, you hear with your brain as it constructs sounds based only in part on the sense data from your ears. Your experiences of smell, taste, and touch are similarly constructions. So is the feeling of your heart beating in your chest when you run up the stairs and your lungs expanding as you take a deep breath.”

Myth #5: Your brain reacts to events in the world

“As you go through your day, it may seem like your brain is constantly reacting to events around you. You see a cute puppy and you smile. A friend makes an embarrassing remark and you blush. You’re pricked by a vaccine needle and you feel a twinge of pain. But under the hood, your brain’s neurons do not sit idle until the world turns them on, like some cartoonish chain reaction.”

“Instead, your brain is constantly guessing what might happen in the next moment, and comparing its guesses to the sense data that it receives from the outside world and inside your body. These guesses are the seeds that give rise to your actions and your experiences.”

“In fact, your brain begins to conjure your actions and experience before receiving sense data from your eyes, ears, nose and so on. Your brain is not reacting to the world — it is forever predicting, like a fortune teller, imagining what your world will be like, how you will act, and who you will be. The information streaming in from your senses can confirm those predictions; or it can adjust them, a process you might know as “learning.” You can’t feel this predictive drama happening. It’s so quick and effortless that you feel like you’re reacting.

Myth #6: Mirror neurons are special cells that create empathy

“Several decades ago, some scientists observed neurons that seemed to have a particular kind of symmetry. They increase their activity when you take a particular action, such as waving your hand, and also when you watch others performing a similar action. These neurons were dubbed “mirror neurons” for this seemingly unique behaviour. But in reality, they are just everyday neurons engaged in ordinary, miraculous prediction.”

“In every moment, your brain’s predictions begin as silent commands to move parts of your body, like adjusting your heart rate, contracting your intestines, gushing some hormones, or raising your arm. Copies of these commands are sent to your sensory systems to become predictions of what you’ll see, hear, and feel if you move.”

“These commands are sometimes executed and sometimes not, but they turn out to be a critical part of your ability to perceive anything at all, including the actions of other people. So, the same neurons that help you wave hello to a friend enable you to see someone else wiggle their fingers in their air and to understand it as a greeting. It’s not “mirroring,” it’s a normal part of your brain’s predictive process.”

Myth #7: Your brain stores memories

“A brain doesn’t store memories like a computer stores files, to be retrieved whole when needed. Your brain reconstructs your memories on demand with electricity and swirling chemicals. We call this process “remembering” but it’s really more like “assembling.” And each time a memory is assembled, it might be built with some different neurons. It’s also influenced by your current situation, so each occurrence may differ in its details.”

“This is one reason why eyewitness testimony in legal trials can be unreliable. Memories are highly vulnerable to reshaping. In one study of convictions that were later overturned by DNA evidence, 70 per cent of the accused were convicted based on eyewitness testimony.”

cc

Myth #7½: You can’t grow new brain cells

“This myth is partly true (so it’s just half a myth). Most areas of the human brain cannot grow new brain cells, but some parts can. One such part is the hippocampus, which is important for learning, remembering, regulating how much you eat, and other biological functions.”

“Interestingly, many other animals can regrow neurons throughout much of their brains. Why can’t we? Some scientists wonder if it’s a price we pay for living long lives. A long life requires a dependable memory. Your brain needs a way to reassemble past experiences not just from days or weeks ago, but across the span of years. New neurons, like the ones that sprout in your hippocampus, may be for learning new things and making new memories, rather than remembering (reassembling) the past. In a sense, new neurons enable your brain to cultivate your past as a way of charting your future.”

Seven and a Half Lessons About the Brain by Lisa Feldman Barrett, Picador Publishing.

%d bloggers like this: