Chemically Modifying
Behaviors
Copyright 2010:PEER.tamu.edu
Students will learn:
– How drugs interact with the
brain and nervous system
receptors
– The different types of drugs
most commonly used and how
they affect behavior
– Drug tolerance and addiction
How Drugs Work In The Brain
A given drug may act in one
of the following ways:
1. Mimic
neurotransmitters
2. Increase or decrease
the amount of
neurotransmitter
released
3. Block receptors
4. Prevent the reuptake of
neurotransmitter
Prescription Drugs
Affect Behavior
• Drugs affect behavior by altering one or
more neurotransmitter systems.
• They are one way to treat mental health
disorders, like depression.
When to Prescribe Drugs
• The decision to prescribe behavior
modifying drugs, like antidepressants,
is based on:
1. How severe the
person’s disorder is
2. The person’s history
of illness, and
3. The person’s age
Many times, psychological therapy
(counseling) is prescribed along with
medication.
Antidepressants to Relieve
Depression:
• Antidepressants help relieve the symptoms of
depression by restoring the brain’s chemical
balance.
• Antidepressants help reduce specific symptoms
associated with depression, like:
• extreme sadness
• hopelessness
• lack of interest in life
Antidepressants Alter Balance
of Specific Neurotransmitters:
• Work by altering the
balance of the specific
neurotransmitters in
the brain that affect
mood.
• The neurotransmitters
that affect mood are:
serotonin, dopamine, &
norepinephrine
Serotonin Affects Behavior
• Regulates the following
functions:
–
–
–
–
–
Mood
Appetite
Sleep
Muscle contraction
Some cognitive functions
including memory and
learning
Addictive
Substances
and Their
Affects
Psychological vs. Physiological
Addiction:
Psychological: Drug is
taken because you
“feel good”
Physiological: Drug is
taken because body
and brain need/crave it
Most addictions begin psychologically and
evolve into physical dependence and
addiction.
Drug Tolerance is:
• Decreased susceptibility to
the effects of a drug due to
its continued use.
• The amount of drug must be
increased to reach the
desired effect
Tolerance depends on
the individual and the
drug
• Can happen with any drug
Tolerance and addiction
develop together
Nicotine Addiction is a
Serious Problem
• Nicotine is the addictive and
toxic substance found in tobacco
products such as cigarettes,
cigars, snuff, dip, and chewing
tobacco
• 70.9 million Americans use
tobacco products, about 46
million adults smoke
• Smoking is the fastest way to
get nicotine into the brain and
cause its addicting affects
Nicotine’s Effects
• First, stimulates the adrenal gland
causing a release of adrenaline
– Increased heart rate
– Increased breathing
– Increased blood pressure
• Second, stimulates nicotinic receptors
in the brain
– Release dopamine in the reward
centers, makes you feel good
– Body then craves nicotine to
support continued dopamine
release
Nicotine is directly
linked to cause
cancer, heart disease
and emphysema.
Is a Nicotine Vaccine Possible?
When nicotine enters
the body, it Quickly
spreads to all areas of
the body, including the
BRAIN.
It is in the brain that the
nicotine creates the
reward sensations,
thus making the
tobacco user addicted.
The vaccines being
tested are meant to
stop the nicotine from
traveling through out
the body to include the
brain, thus creating NO
REWARD response!!!
With No Reward Response, tobacco users should
lose interest in using the tobacco products!!!
Do you know what
emphysema is?
Alcohol:
Serious Health Affects
• Absorbed into the blood
stream through the GI tract
• Alcohol in the blood then
travels to the brain and
effects the nerve cells
• Slows communication
between the nerve cells
which depresses the central
nervous system
Alcohol Affects the Brain:
Alcohol and Your Ability to
Think:
• As a person becomes intoxicated the mental and
physical effects of alcohol become more pronounced
This picture
shows a
normal brain
solving
problems on a
test.
This pictures
shows a brain
affected by
alcohol trying to
solve the same
problems. Notice
the decreased
activity!
Blood alcohol levels can get so high that it depresses (stops) the
parts of the brain which control breathing (autonomic nervous
system) and can cause death!
Ritalin, a Prescription Drug
Being Abused
• Used for treatment of
attention deficit disorder
(ADD), attention deficit
hyperactivity disorder
(ADHD), and narcolepsy
• Acts on the central
nervous system as a
stimulant by increasing
dopamine levels
Ritalin is Effective
for Patients that
Need it!
• Has a calming and focusing effect on
people with ADD and ADHD
• Works like caffeine but it is more powerful
• But because it is a stimulant it is abused
by people who do not have ADD or ADHD
Stimulant Abuse
• Some college students take Ritalin or Adderall
because they think it will help them perform better
on tests
• Both drugs are addictive and can cause a racing
heart, confusion, disorientation and even
psychotic behavior!
• It is more useful to learn how to be a better
student! Go To: http://thankyoubrain.com
Additional Addictive and
Harmful Drugs:
Sedatives or Barbiturates - Depresses Central Nervous
System, used in sleep aids – VERY ADDICTIVE
Opiates/Heroin – Used in painkillers, over use stops brains
natural painkillers (endorphins) causes body and brain to become
dependent on outside source – VERY ADDICTIVE
Marijuana - Inability to concentrate, increased anxiety, nausea,
and possible link between long-term marijuana use and schizophrenia.
Leads to increased drug use.
Cocaine – Causes the following damage, heart problems,
including heart attacks, respiratory failure, nervous system problems,
including strokes and Digestive problems. VERY ADDICTIVE
Learn how drugs alter the brain’s
reward pathway with the Mouse Party
Game
Click on the link below:
http://learn.genetic
s.utah.edu/content
/addiction/drugs/m
ouse.html
Another look at a
drug addicted brain
Conclusion
• All drugs that act on feelings and behavior
change the function of nerve cells.
• Some of these changes may become
permanent with continued drug use.
Drugs are taken to alleviate sickness
Ask yourself this:
What is the sickness you take mind- altering
drugs for?