10 Fascinating Facts About the Human Brain

Science & Technology

1. THE BRAIN STARTS AS A TUBE
The development of the brain starts from cells called the neural plate folds, which then fuse into the neural tube. This tissue then becomes the central nervous system, which consists of the brain and the spinal cord.

2. THE HUMAN BRAIN IS BIG
The average adult brain weighs between 1.3 and 1.4kgs. Some neurosurgeons describe the texture of
a living brain as that of toothpaste, but others compare it to soft tofu. About 80% of the contents of the cranium are the brain, while equal amounts of blood and cerebrospinal fluid - the clear liquid that buffers neural tissue - make up the rest.

3. BUT IT IS GETTING SMALLER
5,000 years ago, humans had brains that were even larger. Research proves that the brain has shrunk about 9 cubic inches - that's roughly 10% since then. Researchers aren't sure why the brain might be shrinking, but some are of the opinion that the brain is evolving to be more efficient. Others think our skulls are getting smaller because our diets include more easily chewable foods and so large, strong jaws are no longer required.

4. THE BRAIN USES A LOT OF ENERGY
The modern brain is an energy hog. The organ accounts for about 2% of body weight, but uses about 20% of
the oxygen in our blood and 25% of the glucose (sugars) circulating in our bloodstream.

5. WRINKLES MAKE US SMART
It is believed that smarter people have more wrinkles in their brain. The surface of the human brain is covered by deep fissures, smaller grooves called sulci and ridges called gyri. This surface is called the cerebral cortex and is home to about 100 billion neurons or nerve cells. The folded surface of the brain allows the brain to pack in more surface area and thus more processing power. Research done by Emory University (USA) neuroscientist Lori Marino has found that dolphins have even more pronounced brain wrinkles than humans.

6. IT'S MORE THAN JUST NEURONS
Researchers earlier thought that neurons occupied most of the brain, however new studies have shown that neurons take up just 10% of the brain. The other 90%, which accounts for about half the brain's weight, is taken up by glia, which means 'glue' in Greek. Neuroscientists used to think that glia was simply sticky stuff that held neurons together. But recent research shows that glia mops up excess neurotransmitters, provides immune
protection and also actually promotes and modulates synapse growth and function making the brain more efficient (synapses are the connections between neurons).

7. THE BRAIN IS EXCLUSIVE
The blood-brain barrier that covers the brain is an assembly of cells in the brain's blood system that lets only a few molecules enter the brain. The capillaries that feed the brain are lined with tightly bound cells, which keep out large molecules, allowing only special proteins, necessary nutrients and certain substances to enter the brain.

8. TEEN BRAINS AREN'T FULLY FORMED
The grey matter of the brain (the brain is formed of grey matter and white matter) peaks just before puberty with some of the most dramatic development happening in the frontal lobes, the seat of judgment and decision-making. A 2005 study published in the journal, Child Development, found that the parts of the brain responsible for multitasking don't fully mature until we're 16 or 17 years old. Research also revealed that teens were less likely than adults to use the medial prefrontal cortex, an area associated with empathy and guilt. Teens learn empathy by practicing socialising.

9. THE BRAIN NEVER STOPS CHANGING
Scientists once thought that as soon as a person hits adulthood, the brain loses its ability to form new neural
connections. This ability to form new connections is called plasticity and was thought to be confined to infancy
and childhood. However, research in 2007 proved this theory wrong. The study found evidence of human
neurons making new connections in adulthood too.

10. NO DIFFERENCE
The male and female brains and brainpower are similar. However, male and female hormones affect brain development differently.

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