You have brain cells in your anus, lots of them, which accounts for any number of insightful comments.
Brain cells are called ‘neurons‘ and they are a type of cell whose primary function is to transmit or relay information. The brain has about 90-100 billion (that’s 100,000,000,000). They are also found in the gut (only 100 million of them) stretching from your esophagus to your arse.
The dendrites are the conduits (wiring) from each neuron along which the neuron sends and receives information. As the dendrites grow out of the cell in response to your need for more information or performance, the dendrites connect to dendrites from nearby neurons, thereby tapping into the internet in your head.
Where they join is called a ‘synapses’ (connection/junction points) and the more you have the better. These dendrites are input-output lines to other neurons.
The axon is the neuron’ s output line to the nerve endings which are activated when you need to bend your elbow to satisfy that raging thirst for a beer.
The axon line is mostly covered by the essential insulation cells called glia.
Glia are the unsung heroes of the brain, they not only anchor the neurons in place, they bring in the nutrients to feed the neurons, they clean up debris and dead neurons and to top it off, actually speed up the signal transmission rate to the nerve endings.
A large part of mammal brain function is given over to routine tasks in the sub-conscious department of which we are barely, if at all, aware including breathing, sending off the signal to tell the heart to beat one more time, driving the car and countless other tasks.
Even more mundane tasks like digestion management, moving wastes out of the system, stocktaking for resupply (hunger) and countless others are done by another, separate sub-conscious brain (100 million neurons) located in the gut which reports directly to the primary brain’s sub-conscious department in the head.
These is strong evidence emerging that data from the second brain in the gut has a significant impact on the workings of the brain sub-conscious which affects mood, including depression and most of the decision making in the conscious part of the brain.
There is little change in the number of neurons during a life time as many of them remaining in place for the entire life cycle of the person. Some neurons are replaced when worn out.
Our brains probably have the same number of neurons as Einstein. Everyone has enough neurons to be a genius, but that depends largely on the number of connections and the arrangement of those connections. This number can grow significantly in a relatively short time span with a huge effect on cognitive ability, so yes, you can get smarter. Unfortunately, it also means you can get dumber.
And no, we don’t use just 10% of our brains, we use the whole lot. Sheech.