The human brain has an estimated 70 to 100 billion neurons

that fire along ever changing pathways.

Our brains are always changing for better or for worse.

Modern research has demonstrated that the brain continues

to create new neural pathways and alter existing ones

in order to adapt to new experiences,

learn new information, and create new memories.

Neurons are information messengers.

They use electrical impulses and chemical signals

to transmit information between different areas of the brain

and between the brain and the rest of the nervous system.

And when those chemical signals the neurons use,

change, we change.

And if the chemical change is drastic,

the change in us can often be drastic as well

for better or for worse.

Anyone who suffered from a severe episode of mental illness

or who has gotten really, really high

on one of many mind-altering drugs that affect brain chemistry

can attest to changing chemistry,

really affecting how one behaves,

thinks, feels, acts, et cetera.

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