How Drugs How Drugs Alter The BrainAlter The Brain

Remembering the Remembering the Basics….Basics…. The brain is composed of millions of The brain is composed of millions of

interconnecting interconnecting nerve cellsnerve cells, called , called NEURONS.

Each Each neuronneuron is composed of: is composed of:

Axon:Axon: long single fiber, ending in thousands of long single fiber, ending in thousands of nerve endings that nerve endings that transmit or send messagestransmit or send messages from the cell body to the dendrites of other neurons.from the cell body to the dendrites of other neurons.

Dendrite:Dendrite: short fibers that short fibers that receive messagesreceive messages from from other neurons and relay them to the cell body.other neurons and relay them to the cell body.

Cell Body:Cell Body: contains the DNA/genetic blueprintcontains the DNA/genetic blueprint, , the cell body the cell body processes the informationprocesses the information and and directs the activitiesdirects the activities of the neuron. of the neuron.

Synapse/Synaptic GapSynapse/Synaptic Gap – the – the spacespace between the neuronsbetween the neurons

Remember…. The Areas of The Remember…. The Areas of The BrainBrain Brain Stem

(survival – breathing etc..)

Cerebellum (coordination, balance)

Sensory Cortex (senses)

Prefrontal Cortex (decision making,

judgement, regulating emotions, etc…)

Limbic System (feelings and

emotions)

Remember Remember This…This…

An electrical signal An electrical signal (message)(message) moves moves down an down an axonaxon

This triggers a This triggers a specific specific neurotransmitteneurotransmitterr to be released into to be released into the the synapsesynapse

It carries the It carries the message and is message and is received at the received at the dendritedendrite of another of another neuron.

How does the Brain How does the Brain Communicate??Communicate??

NeurotransmissionNeurotransmission = = communication between communication between brain cellsbrain cells (In order for the brain to (In order for the brain to function so that a person can think, move, or function so that a person can think, move, or feel, neurons must communicate – this is feel, neurons must communicate – this is called called neurotransmissionneurotransmission))

NeurotransmittersNeurotransmitters = = chemicalschemicals that carry messages around in the brain. that carry messages around in the brain. (dopamine, serotonin, adrenaline, etc..)(dopamine, serotonin, adrenaline, etc..)

Different Neurotransmitters are Different Neurotransmitters are attracted to different receptors and attracted to different receptors and trigger different messages. trigger different messages.

Much like the way a key fits into a lock. Much like the way a key fits into a lock. If the key fits, the receiving neuron will If the key fits, the receiving neuron will be able to process the signal and send it be able to process the signal and send it on.on.

All of that should have been All of that should have been REVIEW!!!!REVIEW!!!!

Now for the new stuff…Now for the new stuff…When Drugs are IntroducedWhen Drugs are Introduced

Once introduced, Once introduced, drugs change drugs change how the brain works.how the brain works.

Regardless of whether a drug is Regardless of whether a drug is swallowed, sniffed, inhaled, injected, swallowed, sniffed, inhaled, injected, absorbed etc… drugs will eventually absorbed etc… drugs will eventually travel through the circulatory travel through the circulatory system and reach the brain.system and reach the brain.

Pathways To The BrainPathways To The Brainhttp://science-education.nih.gov/supplements/nih2/addiction/activities/http://science-education.nih.gov/supplements/nih2/addiction/activities/

lesson3_pathways.htmlesson3_pathways.htm

Drugs in the BrainDrugs in the Brain Once in the brain, drugs can affect Once in the brain, drugs can affect

almost any step in the communication almost any step in the communication between neurons.between neurons. Drugs can Drugs can stimulate or activatestimulate or activate our our

natural chemicals.natural chemicals. Drugs can also Drugs can also imitate or mimicimitate or mimic our natural our natural

chemicals. chemicals. Drugs can eventually Drugs can eventually replacereplace our own natural our own natural

chemicals.chemicals. Drugs can Drugs can damage and destroy damage and destroy

receptorsreceptors, so that messages cannot be , so that messages cannot be received by certain neurons.received by certain neurons.

Drugs Fool The BrainDrugs Fool The Brain

When drugs trick the brain a When drugs trick the brain a temporarytemporary pleasurable pleasurable sensationsensation occurs. occurs.

This exceeds pleasure felt by This exceeds pleasure felt by “normal” things…. Yummy food, “normal” things…. Yummy food, funny movie etc…funny movie etc…

The The brain likes pleasurebrain likes pleasure and and wants more, wants more,

so it tells you to get more. so it tells you to get more.

What happens after???What happens after??? Once drugs are out of your system, Once drugs are out of your system,

you don’t go back to normal. you don’t go back to normal. Things that once gave you pleasure Things that once gave you pleasure

are are NOT NOT as pleasurable.as pleasurable. Your body feels the negative effects Your body feels the negative effects

– – you feel the opposite of the you feel the opposite of the high.high.

AND THEN….AND THEN….

This causes This causes withdrawal symptomswithdrawal symptoms - - psychologicalpsychological (anxiety, stress, (anxiety, stress, depression, paranoia)depression, paranoia) and/or and/or physical physical (headaches, shakes, sick (headaches, shakes, sick feeling)feeling)

You need to use even You need to use even MOREMORE of the of the drug to feel the same pleasure next drug to feel the same pleasure next timetime. (. (tolerance developstolerance develops))

How does the brain adapt to the How does the brain adapt to the drugs?drugs?

(Neuroadaptaion)(Neuroadaptaion) Not only does the brain like to feel Not only does the brain like to feel

good – it also likes to be in BALANCE.good – it also likes to be in BALANCE. The brain adjusts by The brain adjusts by increasing or increasing or

decreasingdecreasing the actual number of the actual number of receptorsreceptors to try BALANCE the to try BALANCE the extremes.extremes.

The brain adjusts by The brain adjusts by decreasingdecreasing the the amount of our amount of our natural “feel good” natural “feel good” chemicalschemicals that are produced to try to that are produced to try to BALANCE the extremes… BALANCE the extremes…

So then what??So then what??

The user gets stuck in this “addiction”The user gets stuck in this “addiction” They want the high the drug gave They want the high the drug gave

them, their brain CRAVES it.them, their brain CRAVES it. But their brain can’t handle all the But their brain can’t handle all the

chemicals – so it tries to BALANCE chemicals – so it tries to BALANCE things out.things out.

BRAIN CHEMISTRY and BRAIN CHEMISTRY and FUNCTIONING is altered and people FUNCTIONING is altered and people get stuck in this cycle!!!get stuck in this cycle!!!

How addiction changes your brain – How addiction changes your brain – YouTubeYouTube

Explain it to me: Addiction – Explain it to me: Addiction – YouTubeYouTube

The Science of Addiction - YouTubeThe Science of Addiction - YouTube