Principles Of Neuroscience Lecture 33 Drugs And The Brain Flashcards
What are some common psychoactive drugs?
Ethanol Caffeine Nicotine Heroine Cocaine LSD Valium Prozac
What are the general features of psychoactive drugs?
Small
Lipophilic
Resemble endogenous chemicals
What are the two reasons that psychoactive drugs are used?
- Pleasure - Hedonic drugs
2. Novelty - Psychadelic drugs
What are the features of hedonic drugs?
- addictive
- tolerance exhibited by the users
What are the features of psychedelic drugs?
- not as addictive as hedonic drugs
- not associated with tolerance
What is interesting about tobacco?
It is highly addictive, however, the users do not show tolerance
What aspects of brain function are affected by psychoactive drugs?
- Behaviour
- psychomotor agitations - Mental function
Which functions of the PFC are altered by drugs?
- Motivation
- Perceived salience
- Emotional state
- Meaning and significance
- and vigilance
- Hedonic experience
How do psychoactive drugs act?
Since they are small and lipophilic, they can cross the blood brain barrier
There are chemical homologous in the brain with their own receptors. Drugs bind to see receptors and alter the kinetics of neurons
Describe what the research of opiate receptors lead to
Researchers were looking for the opioid receptor
Once they found it, they discovered the endogenous compound; endorphins
What are the different classes of neurotransmitters?
Amino acids: glutamate, glycine, GABA
Small amines: noradrenaline, acetylcholine
Peptides
What systems in the brain do psychoactive drugs work on?
The neuromodulatory systems
What is the effect of LSD?
How does it act in the brain?
LSD causes hallucinations, “mind expanding” experiences
Serotonin agonist
How do amphetamines and cocaine act in the brain?
These hijack the dopamine and noradrenaline systems
Which general features seems to be always seen in addictive drugs?
Give an example
Enhancement of the dopaminergic signal transduction
Eg. nicotine acts on nAChR, leading to increased dopamine