Transcript Drugs & their effects on the CNS

Drugs & their effects on the CNS
http://www.youtube.com/watch?v=nl5gBJGnaXs
Name some drugs…
What ARE Drugs?????
Drug Definition
• Any substance that alters mental
functioning and whose use can lead
to abuse or dependence.
Did you know: Caffeine
Did you know
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Marijuana has over 200 nicknames
Bart Simpson – street name for LSD/Acid
One in ten people who drink become alcoholics
40% of the US population has tried marijuana
Students spend $5.5 billion on alcohol
Ingredients in Coca Cola(long time ago) was a
liquid extract of the coca leaf and did in fact
contain cocaine
• It would take 800 joints to kill a person—but the
cause of death would be carbon monoxide
poisoning
3 Types of Substance Using Behaviour
1. Recreational use:
using drugs in a way that does not lead to any
health complications or behavioural problems
2. Substance abuse:
using drugs in a way that may cause physical,
emotional, psychological, or social harm to users
or those around them
3. Substance dependence:
can be sudden or gradual, when someone can no
longer stop using a substance without
experiencing physical or psychological suffering
2 types: physical and/or psychological
How do drugs work?
YOUR BRAIN ON DRUGS....
Drugs: Neurons & Synapses
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Recall: For one neuron to send an electrical
impulse to another, it secretes a chemical
messenger called a neurotransmitter (NT) (ex:
dopamine) into a gap (synaptic cleft) between it and
the next neuron
It is on this process that drugs act:
1. Some drugs imitate natural NTs
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Morphine, nicotine, etc.
2. Some increase the secretion of natural NTs
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Cocaine, ecstasy, etc.
3. Some block the effect of natural NTs
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Alcohol
Check these out
• Cocaine and the Brain
• http://www.bbc.co.uk/programmes/p00dbt
6c
Stimulants and Depressants
– Stimulates neurons (causes increase in electrical
activity)
• Caffeine
• Ecstasy
• Cocaine
• Nicotine
– Depresses neurons (causes decrease in electrical
activity)
• Alcohol
• Xanax® and Valium®  for people with anxiety
• Narcotics (opium, morphine, codeine, heroin)
Stimulants
– Symptoms of cocaine use:
• euphoria (exaggerated feeling of well-being)
• dilated pupils
• rapid heart rate
• restlessness and hyperactivity
– Symptoms of cocaine withdrawal:
• fatigue and malaise
• depression
• vivid and unpleasant dreams
Depressants
• CENTRAL NERVOUS SYSTEM DEPRESSANTS
– Symptoms of alcohol use:
• slurred speech
• lack of coordination
• decreased attention span
• impaired judgment
– Symptoms of alcohol withdrawal:
• anxiety
• tremors
• seizures
• increase in blood pressure, pulse, and
temperature
• delirium
Marijuana (pot, weed, ganja…)
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The active ingredient in marijuana is THC
THC produces euphoria and a mild disorientation.
Vivid sensation, and perception of time may be distorted.
THC affects three key brain functions:
– Memory: Pot disrupts short-term memory
– Motor skills: slow reaction time = serious problems for
inexperienced teen drivers.
– Thought: Higher-order thinking skills affected,
including calculation skills and the ability to follow
complex instructions.
• These effects last several hours, although some subtle
changes can linger into the next day.
• Other short-term effects include increased appetite and
heart rate, and reddening of the eyes.
Marijuana (pot, weed, ganja…)
• Research often changes but some long-term effects
known are:
– Heart/Lungs
• It could pose a risk to people with heart problems
or hypertension. Long-term pot smokers could be
subject to many of the same smoking-related
diseases as cigarette smokers.
– Hormones
• Marijuana lowers levels of sex hormones in both
sexes. In adolescents, could affect sexual
maturation
– Brain
• Research shows that marijuana can interfere with
the process by which short-term memories are
encoded and stored in the brain. And even
though such impairment seems to be reversible,
its effects on school grades definitely isn't.
Drugs: Short & LONG term changes
• Alcohol, methamphetamine (meth), and
MDMA (Ecstasy) can kill neurons.
– Unlike other types of cells in the body,
neurons in many parts of the brain have little
or no capability to regenerate.
– Alcohol kills neurons in the part of the brain
that helps create new memories. If those
neurons die, the capability for learning
decreases.