Drug Addiction and Your Brain

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Drug Addiction and Your Brain
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Introducing Your Brain

• Command center of your body
• Weighs three pounds.
• The brain consists of several large regions, each
  responsible for activities vital for living.

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Brain Stem

• The brain stem is the part of the brain that
  connects the brain and the spinal cord.
• It consists of the midbrain, pons and medulla.
• Midbrain- serves as the nerve pathway of the
  cerebral hemispheres. It controls responses to
  sight, eye movement, pupil dilation, body
  movement and heating.
• Medulla- Is the relay station for the crossing of
  motor tract between the spinal cord and brain.
  Contains cardiac and respiratory centers. Also
  controls reflexes like coughing, swallowing and
  vomiting.
• Pons- bridge that links parts of the brain to the
  relay station. Controls sleep, arousal, and
  automatic functions.

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Limbic System

• Buried under the cortex is the Limbic system.
• Controls our emotions and motivations and is
  responsible for actions relating to basic needs
  and emotions.
• This is also where the feelings of pleasure from
  eating, sleeping and memories come from.

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Cerebellum

• Coordinates skilled repetitive movements in order
  to maintain balance and posture.
• Responsible for things you learn once, i.e.
  throwing a ball, walking.
• Involved in the delegating, attending and
  processing of language and music.
• Provides proprioception- this is an intuitive map
  of your body parts- it is what helps us walk in
  the dark.
• Called the little brain as it contains 50 of
  all the neurons in the brain.

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Cerebral Cortex

• Considered the-Thinking part of you
• Divided into 4 different lobes.
• Frontal Lobe- involved with decision making,
  problem solving, math and planning. Enables us
  to interact effectively and takes part in the way
  we experience the world.
• Parietal Lobe- Involved with the reception and
  processing of sensory information from the body.
• Occipital Lobe- involved with vision
• Temporal Lobe- involved with memory, emotion,
  learning and language.

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Diencephalons

• Contains the thalamus and hypothalamus.
• The thalamus is involved in sensory perception
  and regulation of motor functions like movement,
  and impulse. It also regulates level of
  awareness and activity. If this is damaged a
  result could be a coma.
• The hypothalamus regulates hormones including the
  onset of puberty, rhymic cycles in the body, body
  temperature, adrenal glands, etc. It acts as
  ones biological clock.

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Nerve Cells and Neurotransmission

• The brain is made up of billions of nerve cells,
  known as neurons.
• Neurons have 3 important parts
• Central cell body- directs all activities of the
  neuron.
• Dendrites- receives messages from other neurons
• Axon-transmits/sends messages from cell body to
  dendrites of other neurons or to body tissue and
  muscles.

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Neurons Cont.

• In a neuron, a message is sent by an electrical
  impulse.
• This electrical message travels along the sending
  branch, or axon, of the neuron.
• When the messages reaches the end of the axon, it
  causes the release of a neurotransmitter.
• The chemical travels across a tiny gap also known
  as the synapse to other neurons.

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Neurons and Drugs

• Pleasure, which scientist call reward, is a very
  powerful biological force for our survival. If
  you do something pleasurable, the brain is wired
  in such a way that you tend to do it again.
• There is a specialized set of nerve cells devoted
  to producing and regulating pleasure. These
  cells use a chemical neurotransmitter called
  dopamine.
• These dopamine neurons relay messages about
  pleasure through their nerve fibers to the limbic
  system.

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Brain on Cocaine

• The yellow highlighted area is where cocaine is
  binding and attaching itself.
• Here in the picture we can see what happens for a
  period of 30 minutes following the use of cocaine.

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Long Term Effects of Drugs

• Once addicted the brain starts to show long term
  effects, meaning the brain litterly changes.
• The level of healthy brain function is
  highlighted in yellow.
• Top row is that of a normal brain.
• Middle row is with 10 days of no cocaine use.
• Bottom row is no cocaine use for 100 days.
• There is a concern that the brain may never be
  able to recover for long term substance use.

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Drug Addiction

• Drug addiction starts by the act of taking a
  drug.
• Trying a drug is a voluntary descion.
• Maybe I should see what its like.just this
  once,
• A friend dares you
• Your want to feel good or forget your troubles.
• Prolonged drug use changes the brain. Drug use
  effects each individual differently based on
  their bodys make up.
• The brain no longer experience pleasure without
  the drug. At this point, deciding to use drugs
  is no longer a voluntary choice. You have become
  addicted.
• Addiction is therefore characterized by an
  compulsive, drug craving, that persists even in
  the face of negative consequences.

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Drug Addiction

• Drug abuse and addiction effects every segment of
  society- Not one person is immune to the disease.
• Forget the stereotype of a drug addict hanging
  out on a dangerous street corner. Anyone can get
  hooked on drugs, your friend, members of your
  family, your neighbor.
• Trying a drug for whatever voluntary reason will
  cost you much more than what you bargained for!

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Marijuana (What is it?)

• Greenish-gray mixture of dried, shredded buds,
  leaves, stems, seeds and flowers of Cannabis
  sativa, hemp plant.
• The major active chemical in marijuana is THC
  (delta-9- tetrahydrocannabinol).
• There are also 400 other chemicals found in
  marijuana which some have been found to cause
  lung cancer.

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Marijuana cont.

• There are over 200 slang terms for marijuana.
  Most common are pot, grass, herb, weed, reefer,
  jane, chronic, gangster, boom and ganja.
• Marijuana is either rolled into joints, smoked
  through a pipe, mixed in food, or made into
  blunts.
• Over the years marijuanas potency has increased.
  It is 10-15 times stronger.
• When marijuana is used via blunt, most often
  other drugs such as crack cocaine have been
  included. These are called primos or
  woolies.
• Joints and blunts are also sometimes dipped in
  PCP.

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Marijuana Continued

• Marijuana is the Nations most commonly used
  illicit drug.
• Nearly 98 million Americans age 12 and older have
  tried marijuana at least once.
• 15.7 of 8th graders have tried marijuana at
  least once.
• 14.2 of 10th graders are current users
• Among 12th graders, 42 had tried it at least
  once and about 18 were current users.

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Drug Trends
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Marijuana Statistics
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Marijuana and the Brain

• When someone uses marijuana, the chemicals travel
  through the bloodstream quickly and reach the
  brain within seconds after being inhaled.
• Experience as initially relaxing and mellow.
• Heartbeats become rapid, blood vessels in eyes
  expand, reaction times slow down and coordination
  is effected.
• Later, feelings of paranoia and panic may be felt
  by the user. This interaction of the THC with the
  brain is what causes these feelings and
  reactions.
• Once THC has reached the brain it attaches to
  special places on the brains nerve cells, other
  wise known as receptors.

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Cannabinoid Receptor Sites

• Research has found that there are several regions
  of the brain which contain cannabinoid receptors.
• Receptor sites are activated by a
  neurotransmitter called anandamide.
• Anadamide belongs to a group of chemicals called
  cannabinoids. (THC is a cannabinoid chemical)
• THC mimics the actions of anandamide, meaning
  that THC binds with cannabinoid receptors and
  activates neurons, which causes adverse effects
  on the mind and body.

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Areas of the Brain Effected by THC
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Hippocampus

• This region of the brain processes memory. When
  THC attaches to the receptors in this region it
  weakens short term memory.
• The hippocampus also communicates with other
  brain regions that process new information into
  long term memory.
• If the brain is under the influence of marijuana,
  new information may never register and may be
  lost from memory.
• With use of marijuana, neurons are decreased in
  the hippocampus.

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Other Brain Regions and Functions Affected by
Marijuana Use

• Cerebellum- responsible for balance, posture and
  coordination of movement. Once marijuana is
  used, THC interferes and all the above are
  decreased.
• Cortex/Sensory Perception- THC also interferes
  with messages sent about touch, sight, hearing,
  taste and smell. The receptors which are
  activated in this area results in the brain
  misinterpreting the nerve impulses from different
  sense organs.

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Does Marijuana affect physical health?

• People who smoke marijuana frequently have more
  health problems and are sick more often.
• Those who were sick were due to respiratory
  illnesses.
• Cancer of the respiratory tract and lungs are
  promoted by marijuana smoke.
• Evidence shows that smoking marijuana increases
  the likelihood of developing cancer of the head
  and neck, and that the more smoked, the greater
  the increase.

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Marijuana and Physical Health cont.

• Marijuana smoking triples the risk of cancer in
  areas such as the lungs because it contains
  irritants and carcinogens.
• Marijuana contains 50 to 70 more carcinogenic
  hydrocarbons than tobacco smoke. Ones overall
  immune system is effected by smoking marijuana.
  This is crucial in fighting off diseases and
  bacteria's
• Research also suggest that a persons risk of
  heart attack during the first hour after smoking
  marijuana is four times his or her usual risk.
  This is due to the raise in blood pressure and
  heart rate and reduction of oxygen to the blood.

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Marijuana Effects on School, Work Social Life

• Students who smoke get lower grades and are less
  likely to graduate from high school.
• Standardized test scores decreased on verbal and
  math.
• Workers are more likely to have problems with
  coworkers, have increased absences , tardiest,
  accidents and job turnover.
• Depression, anxiety and personality disturbances
  are all associated with marijuana use.
• Lack of motivation motivational syndrome. Even
  with cessation, could take up to a year to return
  to normal functioning.
• Drivers on marijuana have slow reaction times,
  impaired judgment and problems responding to
  signals and sounds on the road. Study of 150
  reckless drivers, 33 tested positive.

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