It is leading cause of accidental death in our society.

The word itself is derived from the ancient

Roman term for “enslaved by” or “bound to.”

Beating addiction is extremely tough.

The drugs and behaviors that lead to addiction

hijack the brain and wreak havoc in the body.

Time for some real chemistry talk.

(Reactions open)

Nearly 24 million americans over the age of

12 are addicted to alcohol or other drugs.

That’s almost the population of Texas.

Years ago, many people thought that

Addiction was just sign of a flawed character

or a lack of willpower, relegated to hobos

or hilarious Boston bar-dwelling drunkards.

But we now know that’s not it -- brain chemistry plays a big part.

Our brains like stuff that makes us feel good.

It could be alcohol, a jelly donut, romantic

encounters or all kinds of other stuff.

No matter what it is, the things that make you feel good are processed through

the reward seeking pathway in the brain.

A region deep in the brain called the

ventral tegmental area releases a “feel good”

chemical messenger called dopamine

to a region higher up in the brain

called the nucleus accumbens.

This region is involved in aspects of emotion and motivation.

As dopamine surges through the

Nucleus accumbens, we feel a surge

of pleasurable excitement and energy.

The surge of dopamine also makes us

want to do whatever we just did again.

Psychoactive drugs like amphetamines

and cocaine supersize this reaction,

increasing the amount of available dopamine

in the brain by as much as ten times.

The resulting euphoric “rush” or “high”

recalibrates the brain, making it think that this

higher level of dopamine is the new normal.

This sets some people on a course toward drug abuse.

If a person continues using drugs,

The brain adapts to these overwhelming

Surges by reducing the number of dopamine receptors

and making the existing receptors less sensitive to dopamine.

This has a double-whammy effect on drug users.

Fewer dopamine receptors and lower

dopamine sensitivity means a lower

ability to enjoy other everyday activities, like eating donuts.

In other words, you need more of a drug,

food or certain activity to get the same pleasurable rush.

For drug addicts, that might mean more

amphetamines or cocaine to get your brain

to produce that surge of dopamine again.

If you try to quit, you can go into withdrawal.

Think about it. If the drug or activity that was

at the controls of your brain is suddenly

gone, the brain has no idea what to do.

It’s like someone hopping off the

otherside of a see saw from you.

Your dopamine levels crash, and

your system goes out of whack.

Depressants like alcohol chemically slow down your brain.

Alcohol inhibits a molecule called glutamate, which is an excitatory transmitter.

It also boosts GABA, which slows down brain activity.

To counteract the effects of the depressant,

your brain has to produce more adrenaline,

more norepinephrine, to keep you alert and focused.

When you’re not drunk, suddenly you don’t

need that boost, but it’s there anyway.

That can cause tremors, nausea, difficulty

breathing and heart palpitations.

Over time, addiction can cause

permanent damage to the brain.

But this cycle can be broken, and

recovering addicts can go on to lead happy and productive lives.

Bottom line, if you know someone who is addicted

to something, anything, get them help.

There are some great links on recovery and

other resources in the description below.

Be safe out there, chemheads.

Speaking of things that are addictive, check

out our episodes on iPhones and pizza.

And for more weekly chemistry videos,

make sure to hit that subscribe button.