Ten Amazing Brain Facts + vision test videos
What part of you is only 1% to 3% of your body's mass, yet uses 20% of all the oxygen you breathe? Your brain! Here are ten more brain facts.
- Your brain needs a continuous supply of oxygen. A 10 minute loss of oxygen will usually cause significant neural damage. Cold can lengthen this time, which is why cold-water drowning victims have been revived after as nuch as 40 minutes - without brain damage.
- Your brain uses a fifth of all your blood. It needs it to keep up with the heavy metabolic demands of its neurons. It needs not only the glucose that is delivered, but of course, the oxygen.
Your brain feels no pain. There are no nerves that register pain within the brain itself. Because of this, neurosurgeons can probe the brain while a patient is conscious (what fun!). By doing this, they can use feedback from the patient to identify important regions, such as those used for speech, or visualization.
The cerebellum is sometimes called the "little brain," and weighs about 150 grams (a little over five ounces). Found at the lower back side of your brain, you need your cerebellum to maintain posture, to walk, and to perform any coordinated movements. It may also play a role in your sense of smell.
The human brain weighs an average of a little over three pounds, or 1.4 kilograms. Albert Einstein's brain may have been smaller than yours, because he was smaller than average. There is a general correlation between body size and the size of our brains. An elephant's brain is huge - about six times as large as a human brain. However, in relation to body size, humans have the largest brain of all the animals, averaging about 2% of body weight. A cat's brain? It weighs about one ounce, a little over 1% of body weight.
There are about 100,000 miles of blood vessels in the brain. If they were stretched out (there's a nice thought!) they would circle the earth more than four times. If you have an average sized brain, you have about 100 billion neurons up there. You'll be happy about that after reading the next item.
Approximately 85,000 neocortical neurons are lost each day in your brain. Fortunately, his goes unnoticed due to the built-in redundancies and the fact that even after three years this loss adds up to less than 1% of the total. Oh, and look at the next item. Recent research proves that your brain continues to produce new neurons throughout your life. It also proves that it does so in response to stimulation (do those brainpower exercises). Scientists refer to this as brain plasticity or neuro-plasticity. You may find this one the most encouraging of these brain facts.
An Open Mind?
Why is an open mind like an open well? Because it is easily contaminated by anything the wind blows in. This is the problem with what many call an open mind, in any case - like someone who is considered open minded because he believes in visitors from space, bending spoons with mind power, and "remote viewing" using ESP. This, however, is more a sign of a gullible mind, so let's look at a healthier definition of the term.
An Open Mind - A Better Definition
Of course, we usually like to think that we are open minded, and that this is a good thing. According to a couple different dictionaries this means: 1. Being receptive to new and different ideas or the opinions of others; 2. Not narrow or conservative in one's thought, expression, or conduct.
We might want to fit those definitions, and why not? However, some take this to mean that we must entertain any idea regardless of merit, or that believing in unlikely things is a sign of being open-minded. That gives too much credit to faulty ideas and unsupportable beliefs.
I watched a program on crop circles the other day, for example. Circles and other geometric shapes of flattened crops appear in fields around the world on occasion, and for years many speculated that alien spaceships, "energy vortexes" and other outrageous things caused these. Paranormal "experts" claimed that they could not have been caused by humans, because the crops were not crushed. Many people bought into this hype in the name of having an open mind.
Interestingly, when several individuals and groups finally claimed responsibility, and even showed exactly how they made the designs, they were largely ignored. So much for believer's open minds. They certainly were not open to the most likely scenario - the one with the most evidence. Obviously, many wanted a particular answer (space aliens) or wanted to keep the mystery alive. As a result, to this day tricksters make their designs in fields, only to have paranormal "experts" stomp into the fields the following day and proclaim that "no human could have made these," even going so far as to claim that the films of the circles being made were faked.
Now, being curious about the mystery, and speculating about possible causes is good. And being "receptive to new and different ideas" is also a good thing. But what about adopting beliefs without supporting evidence? I am certainly receptive to the idea that previously unknown forces can cause things to happen, but I think it would be very closed-minded to exclude the possibility that there are more normal explanations - especially when the bulk of the evidence points in that direction.
What does having an open mind mean then? Certainly it means to be receptive to new ideas and to avoid narrowness of thought. But it doesn't mean accepting ideas that make no sense, or adopt beliefs without any reason or evidence. And being open minded has to at least mean being open to the possibility that the explanations we would like or which are more interesting may be wrong ones.
Your brain can analyze various possible explanations for anything, and an open mind may assure you that you consider all those possibilities. Still, it shouldn't prevent you from discarding those explanations without evidence in favor of those there is evidence for. To put it another way, an open mind should never be an excuse to believe anything in the absence of thoughtful analysis.