Do blind people really hear better than sighted people? And why can't you get that irritating tune out of your head?
There are many myths about our brains and as many amazing facts, as revealed in a fascinating new book by SANDRA AAMODT and SAM WANG, two leading neuroscientists.
Here, they explain some of the most surprising secrets of our grey matter...
FACT: You can't tickle yourself
Why does this work? Because no matter how ticklish you may be, you can't tickle yourself.
The patient doesn't feel the tickling because his brain thinks it's his own hand doing the action.
FACT: Looking at a photograph is harder than playing chess
Today's best computer programmes can beat a grand master, but any toddler can beat the top programmes when it comes to making sense of the visual world.
One reason for this is the difficulty in identifying individual objects.
You only see this ambiguity when you see something briefly enough to misidentify it like when that rock in the middle of the dark road suddenly turns out to be a neighbour's cat.
MYTH: You only ever use about 10 per cent of your brain
In fact, its impressive persistence may depend on its optimistic message: "If we use only 10 per cent of our brains normally, think what we could do if we could use even a tiny bit of that other 90 per cent."
The truth is, studies of brain activity show that even simple tasks actually produce activity throughout the entire brain.
FACT: Yawns wake up the brain
The action itself expands our windpipe, allowing air into the lungs and oxygen into the blood, making us more alert.
Think of yawns as your body's attempt to reach full alertness in situations that require it.
They are contagious. No one is sure why, though it might be advantageous to allow individuals quickly to transmit to one another a need for increased wakefulness.
Yawns are not contagious in other mammals, but the ability to recognise a yawn may be fairly general.
For example dogs yawn in response to stressful situations and are thought to use yawning to calm others.
MYTH: Blind people hear better
When tested blind people are not better at detecting faint sounds.
But blind people do have better memories. Since they can't rely on vision to tell them things, they have to use them constantly - helping sharpen their spatial memory (responsible for recording information about the environment).
They also do better at language tasks, including understanding the meaning of sentences, and at pin-pointing the source of sounds, which may be another way of keeping track of where things are.
They seem to improve these abilities by taking advantage of brain space that isn't being used for vision.
FACT: Computer games help you multi-task
The modern world is full of non-stop action instant messaging, e-mail, video games, and it all seems to be happening at once.
If you're over 30, you've probably wondered why younger people aren't overwhelmed by all this stimulation. But their brains are simply trained to handle it.
Sustained practice at multi-tasking increases one's ability to pay attention to many things at the same time.
A major source of practice is playing action video games you know, the kind most parents hate, where the aim is to shoot as many enemies as possible before they shoot you.
These games require players to distribute attention across the screen and to quickly detect and react to events.
In one study, college students who played action games regularly processed information more quickly, could track more objects at once, and had better task-switching abilities.
So, allowing your children to play computer games may not be such a bad thing after all.
MYTH: A bigger brain makes you more intelligent
However, research suggests that your intelligence may depend on when the synapses the gaps between the brain cells form.
Synapses grow and shrink during childhood and adolescence, and the patterns in which this happen may affect intelligence.
FACT: Exercise helps keep your brain fit
As your circulatory system ages, the blood supply to the neurons, or brain cells, is reduced, starving them of the oxygen and glucose they need.
Regular exercise increases the number of small blood vessels in the brain (capillaries), in turn boosting the supply of oxygen and glucose to neurons.
In fact, exercise is the single most useful thing you can do to maintain your cognitive abilities later in life; elderly people who have been athletic all their lives do much better mentally than sedentary people of the same age.
To be effective, exercise needs to last more than 30 minutes per session, to occur several times a week and to elevate your heart rate but it doesn't need to be extremely strenuous (fast walking works fine).
See you at the gym!
FACT: Your brain uses less power than a fridge light
The brain uses just 12 watts of power: less than it takes to power the light in the back of your fridge.
Even though the brain is very efficient, it's an energy hog.
It's only 3 per cent of the body's weight, yet consumes onesixth of the body's total energy.
The cost of thinking hard is barely noticeable most of the brain's energy costs go into maintenance.
MYTH: Listening to Mozart makes babies brainier
The myth began in 1993 when a scientific journal, Nature, reported that listening to the first ten minutes of a Mozart sonata temporarily improved the performance of college students doing a reasoning test.
The idea was picked up a few years later by an American state governor, who played Beethoven's Ode To Joy to the state parliament and requested $100,000 to send classical music CDs to all parents of newborns in the state.
Of course, the politicians failed to notice that it made no sense to argue that music leads to lifelong intelligence gains in babies based on an effect that lasted under 15 minutes in adults!
The Mozart effect took off from there despite the fact that no one has tested the idea on babies. Ever. But by this point the idea that classical music made babies smarter had been repeated countless times in newspapers, books and magazines where stories about the Mozart effect have progressively replaced college students with babies.
But while playing classical music isn't likely to improve your child's brain development, something else will having them play music for you.
Children who learn to play a musical instrument have better spatial reasoning skills i.e. they think about the physical arrangement of the world in a far more mathematical way (possibly because music and spatial reasoning are processed by similar brain systems).
FACT: Stupid tunes are hard to forget
We need to remember sequences every day, from the movements involved in signing your name or in making coffee, to the correct route you need to take off the motorway to get home.
The ability to recall these sequences makes everyday life possible.
As you think about a snippet of a song, your brain may automatically associate it with one of these sequences.
This, in turn, increases the likelihood that you will recall that snippet, which leads to more reinforcement.
It's this cycle which helps the storing of memories.
How can you break this pattern?
One way is to introduce other sequences that interfere with the reinforcement of the memory.