Brain

1. People who ride on roller coasters have a higher chance of having a blood clot in the brain. 

2. It is not possible to tickle yourself. The cerebellum, a part of the brain, warns the rest of the brain that you are about to tickle yourself. Since your brain knows this, it ignores the resulting sensation. 

3. Once a human reaches the age of 35, he/she will start losing approximately 7,000 brain cells a day. The cells will never be replaced. 

4. Women are twice as likely to be diagnosed with depression than men in the United States. 

5. The human brain has about 100,000,000,000 (100 billion) neurons.