Our brain decides how we perceive everything around us. It informs our decisions, guiding us carefully through the fog that is the world around us . . . except for when it lies to us. You see, our brains are fickle friends and love to play games. Often, what we think is true is actually just our brains messing with us.

10 Semantic Satiation

Have you ever repeated a word several times and found that, after a while, it started to lose meaning? If you have, you needn’t worry—scientists have studied this phenomenon and call it semantic satiation. Studies found that as you repeat a word, your brain becomes satiated and you start to get confused about what the word even means. You see, normally when you say a word (e.g., “pen”), your brain finds the semantic information for a pen and connects the two things together. However, counter-intuitively, if you repeat the word a number of times in quick succession, your brain becomes less able to connect it with that semantic information each time.

Researchers have found practical uses for this information beyond just amusing themselves with how easily we trick ourselves—by using semantic satiation in a controlled environment, they have been able to help those who stutter, and in one case were able to help someone with coprolalia, the uncontrollable cursing sometimes associated with Tourette’s syndrome, by having him repeat his favorite curse words over and over.

9 Peripheral Theory Of Emotion






Let’s say you finally get to go on that camping trip you’ve been putting off for a long time. You enjoy a long day of hiking, fishing, and other activities, then go to your tent to get some rest for the next day. When you wake up in the morning, you realize that something is horribly wrong—to be more precise, there is a bear in your tent. You might imagine that the first thing you’d feel is fear, which would result in a rapid heartbeat. But, once again, your brain is deceiving you.

According to James Lange’s theory of emotion, it actually works the other way around. His peripheral theory states that when you see the bear, your heart starts to beat faster, and only then does your brain start to think it must be afraid and send out fear signals. Those who study emotion have not been able to disprove the theory thus far, although some believe emotional responses are more of a loop.





8 Earworms

Have you ever had something incredibly terrible yet catchy stuck in your head for days at a time? Well, now you have a name for this horrible phenomenon, which scientists have dubbed an “earworm.” The explanation some scientists give basically involves your brain getting stuck in a loop. You probably remember one verse of whatever catchy song you are stuck with almost perfectly, but don’t know the rest of the song as well. After singing the first verse, your brain tries to move on to the next, but doesn’t know the rest of the song. Because your brain likes to go back to unfinished thoughts, it gets stuck in a loop, continually trying to start again and finish the song. After presumably struggling to get the Spice Girls out of their heads, a group of scientists were determined to find out how to break this spell. After a lot of study, their advice is a sort of Goldilocks philosophy—you need to focus on a cognitive activity that isn’t too easy or too hard. They suggest solving anagrams or reading a novel.

7 Moral Dumbfounding

Most of us have strong opinions on issues like cannibalism and incest, with the majority of us considering them to be morally wrong. However, researchers have found that, when asked about these issues, most people’s brains sit there sluggishly, unable to come up with an appropriate response, even though the behaviors in question are considered taboo by most modern societies. This phenomenon is termed moral dumbfounding—quite simply, the subjects were “struck dumb” and unable to properly explain why they felt so strongly about an issue.

One of the scenarios described someone working with a body that was going to be cremated anyway and taking a small chunk of flesh home with her to eat. She made sure to cook it thoroughly to remove any diseases. Another told of an adult brother and sister who were on vacation and decided to get freaky, making sure they used protection. The participants were asked if what these people had done was wrong, then asked to explain why. The researchers found that people felt very strongly that these behaviors were morally wrong, but struggled mightily to verbalize their reasoning. Research has not yet explained why this response occurs. It may be that society’s taboos are simply ingrained into our consciousness so deeply that we feel a powerful moral drive against them even though we cannot logically explain why.





6 The GPS Effect

Do you rely on your GPS to get everywhere? Do you even use it to navigate to familiar places? If so, perhaps you might want to consider using it less. It turns out that using GPS is an easy way to lull ourselves into a false sense of security and lose our sense of direction—too much use of GPS actually makes it harder for us to create spatial maps. Even worse, some researchers believe that if we don’t use our spatial abilities regularly, it could lead to a higher risk of early-onset dementia. The researchers suggest that we use GPS only when we don’t know the route, and use it more as a tool than a crutch.

On a more positive note, it turns out that constantly using our spatial abilities makes our brains stronger. London cabbies have to go through an extremely rigorous process to learn their routes, which only cover a 9.5-kilometer (6 mi) radius but include 25,000 streets with 320 separate routes and about 20,000 different points of interest. Researchers studying London cabbies found that not only seasoned veterans but also those who had only just taken the training had an increase in grey matter in the brain. Scientists believe the more important implication of this study is that it shows the human brain is extremely good at adapting well into adulthood.

5 Sensory Deprivation

You probably won’t often end up in a situation where you are temporarily deprived of sensory input. However, if that does happen and you start to see things that don’t make sense or hear strange noises, don’t be too alarmed—it’s just another example of your brain playing tricks on you. Researchers put test subjects in something called an anechoic room, a chamber designed to block out noise and light. The goal of this particular experiment was to see whether people hallucinated when deprived of sensory input.

People reported seeing shapes and faces, and some even had olfactory hallucinations. Even weirder, some thought that something evil was in the room with them and that something “important” had happened while they were in there. According to researchers, the explanation is that our brain gets confused when it is deprived of sensory input, so it creates some to fill the void. The result is that we can’t tell what is real and what is just inside our heads.





4 Sympathetic Pain

Have you ever heard seen someone slam their foot in the door and winced in pain even though nothing happened to you? Or just heard a story of someone getting hurt and had the same experience? That’s sympathetic pain. The researchers who studied this used MRI machines to test how subjects’ brains reacted when looking at faces with certain expressions, and when making those expressions. What they found is that the brain displays the same activity in either case. The part of the brain responsible for this is called the “mirror area” and scientists believe we have something called “mirror neurons,” which are responsible for creating a sympathetic response. Essentially, humans are hardwired to think we are feeling the same things as other people—essentially a very strong version of instinctive empathy.

3 False Memories

Most of us are very sure of our recollections, and why shouldn’t we be? In a strange and ever-changing world that often doesn’t make sense, our experiences can be one of the few things that ground us in reality. However, scientists have conducted experiments on memory and found that it is incredibly easy to plant false memories. According to one researcher, the reason we are so easily fooled is because our minds try to take in everything in our surroundings but inevitably fail, which leads to gaps in memory. To deal with these gaps, our minds automatically plant whatever false memories they think make sense based on our current knowledge and experience.

But it gets even worse. In one experiment, researchers convinced a woman that she had been lost in a mall when she was young. Not only did she believe them, but she started making up details about an old woman who had helped her and talked about looking at puppies. The researchers were able to convince her so well that when they told her the memory was false and it had all been an experiment, she didn’t believe them until she had called her parents to confirm that she hadn’t been lost in the mall.





2 Sleep Drunkenness

Most people probably know that if you go for long enough without sleep, the results can be quite similar to being drunk. However, what you might not know is that too much sleep can have a similar effect. Have you ever slept longer than usual, woken up feeling groggy, and wondered why you should feel bad when you got plenty of sleep? It should stand to reason that you can never sleep too much—sleep is, after all, how we recharge, and many of us are constantly trying to catch up.

When you sleep for too long, your brain can get confused and leave you in a state that is halfway between sleeping and waking. This is dangerous, because many who are sleep-drunk are unlikely to realize how much of a hazard they are on the road. One doctor tells of a patient who was so groggy from sleep drunkenness that his wife thought he was having a stroke.

1 Hypnagogia

Many of us are under the impression that only those under the influence of drugs are likely to experience hallucinations, but nothing could be further from the truth. Hypnagogic hallucinations occur in that span of time when you are falling asleep but not actually asleep, whereas hypnapompic hallucinations occur when you are waking up. Both forms of hallucination can be either auditory or visual in nature. They are distinct from dreaming—research has shown that your brain can cause you to hallucinate when you are still partially conscious. While those who are especially tired or have previously existing mental conditions are slightly more likely to have these experiences, they are very common in healthy individuals as well. And our brains are not satisfied with their games only when we are sleeping or in that twilight state between worlds—neurologically normal people can have auditory hallucinations even when wide awake.

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