Substance Abuse Flashcards
What are the main types of stimulants
Cocaine
amphetamine “speed”
Amphetamine derivatives
What is a stimulant
A drug that arises or accelerates activities
What is a psychostimulant
Anything that stimulates the brain
What are narcotics
Induce narcosis (sleeping)
What are examples of narcotics
Opium, heroin, morphine
What are hallucinogens
Produce hallucinations
What are examples of hallucinogens
MDMA
LSD
Magic mushrooms
Why do we take drugs
They make us feel good by activating the mesolymbic dopamine system
Nucleus accumbens is a major reward area and the ventral tegmental area has large amount of dopamine cell bodies
What is the definition of reward?
Positive reinforcement
What makes a substance rewarding?
The ability to increase dopamine in the nucleus accumbens
What parts of the brain are involved in self stimulation
Median forebrain bundle
Nucleus accumbens
Lateral hypothalamus
What is the evidence for dopamine enhancing reward?
Rats self stimulate the medial forebrain bundle which has lots of dopamine receptor blockers
Natural rewards increase dopamine transmission
Rats will self- administer dopamine like drugs and most drugs of abuse
Drugs of abuse increase dopamine neurotransmission
The rewarding effect of abused drugs is inhibited by dopamine receptor antagonists and lesions of dopamine cells
When does the largest amount of dopamine get released?
When the reward is better than expected
What are the major effects of stimulants
Euphoria and well being
Increased alertness
Increased self confidence
Increased energy
What is an entactogen
Touchy feely grud- promotes closeness to others
What is cocoehtaline
Combination of cocaine and alcohol
Toxic
Increases body temp and heart rate- brain haemphorage and seizures
What is the pharmacology of amphetamines
Reverse the transporter- nothing can get back up and the neurotransmitter can’t get back into the presynaptic terminal- essentially blocked.
What happens when dopamine is released in the dorsal striatum
Repetitive movement (stereotypy)
What are the side effects of stimulant use
Seizures Depression and anxiety Paranoia Psychosis Neurotoxicity (not cocaine)
What are the major effects of opiates
Euphoria and well being
Drowsiness
Relief of osin
Where do opiates operate
Cortex- movement/ sensory
Cingulate cortex- judgement
Thalamus and spinal cord- pain centre
-
Side effects if opiates?
Constipation
Tolerance and withdrawal symptoms
Coma death due to low tolerance
Coma death due to mix with depressants
What are the effects of cannabis
Cortex- motor sensory
Cingulate cortex- judgement
Hippocampus- blunts memory
Cerebellum: blunts motor coordination
What are the effects of repeated ecstasy use
Loss of serotonin, serotonin metabolite sand transporters. Cell bodies are still intact but function abnormally.
Chronic depressive And anxiety states
