Transcript Substance Abuse & The Brain

Substance Abuse & The Brain
Dopamine and The Brain
The hypothalamus is responsible for
primitive emotions such as fear, anger, joy,
and aggression. It is fully developed at birth.
The amygdala is responsible for our more
sophisticated moods such as love, jealousy,
kindness, attraction, etc.
More refined and reasonable than the
hypothalamus
It develops during childhood
Dopamine and The Brain
Dopamine is a neurotransmitter associated
with boosted mood.
When dopamine is injected into the
hypothalamus/amygdala it feels good.
You can do this simply by using your
imagination.
Humans wondered if we could find an
artificial means of spiking our dopamine
levels beyond what we could manage through
our own fantasy thoughts.
Recreational Drugs
Alcohol and Crack Cocaine are two
major dopamine enhancing drugs in use
today.
Alcohol secretes large amounts of
dopamine into the amygdala, creating
the pleasure experience.
Not a bad idea except for the body’s
need for homeostasis
How Addiction Works
Homeostasis: The body’s drive drive and
determination to keep everything the same,
or close to it.
Caffeine Example
Alcohol injects large amounts of dopamine
into the amygdala.
This feels good but the brain doesn’t like
anyone playing with neurotransmitter levels
After a while the brain compensates by
reducing its own dopamine production
How Addiction Works
This is stage one of addiction, known as
tolerance. (reduction in dop. Production)
When you develop tolerance you need more
of the drug to give you the same affect that a
small amount once gave you.
The body has reduced its own production and
now you need more of the drug to produce
the same effect
How Addiction Works
As people increase their consumption of the
drug the brain moves into stage 2: reducing
and removing dopamine receptor sites
Receptor sites are points on the amygdala
where the dopamine atttaches.
If these don’t exist the dopamine cannot
attach and cannot trigger a response from the
amygdala.
Stage 2 will continue until all, or nearly all of
the sites are removed or shut down
How Addiction Works
Stage 3: Crippled Brain
If an addict decides to quit how do they
experience pleasure?
They don’t, the whole system is crippled
They can only come close to feeling
even normal emotions through huge
amounts of the drug that will trigger the
last few remaining receptor sites
Recovery
This is why recovery is so difficult
Depression is intense and suicide rates
are high among recovering addicts
Sometimes receptor sites will rebuild
sometimes they won’t. One can
permanently cripple this system through
substance abuse.
Additional Info.
The rate at which the brain moves through
this process varies widely
The speed at which the brain adjusts tends to
be the part of addiction that is genetic.
Some of us are lucky and have not so clever
brains that can tolerate a moderate amount of
substance abuse.
Others of us have inherited the clever brains
that adjust to changing conditions quite
rapidly. These brains are prone to addiction
problems
Additional Info.
Adolescent brains do not tolerate moderate
recreational drug use as well as adult brains.
The other area of the brain largely affected by
drug use is the pre frontal cortex.
This area of the brain does not mature until
the age of 21 or 22
Alcohol and other recreational drugs are
harmful to the developing pre frontal cortex
Additional Info.
The brain goes through the same
scenario of adjustment with all drugs.
From ecstasy and marijuana to crack
cocaine and pharmaceutical
medications.