Drugs Flashcards
What is a psychoactive drug?
Substances that act to alter mood, thought, or behavior
Influence chemical signaling in the synapse
What type of drug suppresses mental function and produces calming effects through low doses, or results in intoxication through high doses?
CNS Depressant
What type of drugs stimulate arousal by giving your body a rapid, but temporary, boost of energy and clarity?
CNS Stimulants
What type of drug alters perceptual experience and disturbs your sense of reality?
Hallucinogen
What is an example of a CNS Depressant?
Alcohol, opiates, anxiolytics
What is an example of a CNS Stimulant?
Amphetamine, cocaine, caffeine, nicotine
What is an example of a Hallucinogen?
Marijuana, LSD, MDMA
The ingestion of psychoactive substances in moderate amounts in which the substance does not interfere with everyday function.
Substance Use
The use of a substance significantly interferes with the users life.
Substance Abuse
The state in which the user is psychologically and physiologically dependent on a drug - showing tolerance and withdrawal.
Substance Dependence
What is an Addiction?
Uncontrolled drug use that persists in spite of negative consequences associated with taking or obtaining the drug.
What is Tolerance?
The increase in required dose to obtain desired effect.
What is Withdrawal?
Physical and psychological behaviors that are displayed by an addict when drug use ends.
Withdrawal and Homeostasis
- Brain normally exists in a state of drug-free homeostasis
- Taking drug leads to an imbalance
- Compensatory adaptations attempt to restore homeostasis
- Quitting drugs leads to an imbalance in opposite direction - withdrawal
What is the term for diagnosing an addiction?
Substance Use Disorder
Whats are the DSM-5 requirements for diagnosing a Substance Use Disorder on top of maladaptive patterns of use?
- Failure to fulfill major role obligations due to substance use
- Spend great deal of time trying to get drug
- Legal problems associated with substance
- Cravings
- Tolerance
- Withdrawal
What is Reward?
Desirable or positive stimuli that can affect behavior
What is Intracranial Self-Stimulation?
A research model where a rat is fitted with an electrode located in certain parts of the brain which is connected to a level in the rat’s cage.
What type of behavior did rats used in the ICSS model exhibit?
They would press the lever almost endlessly
They would ignore everything around them (food, water, sex) and focus only on the lever
They would eventually either collapse or need to be removed
What discovery did the ICSS lead to?
The Reward System
What is the Reward System?
A circuit in the brain that is responsible for rewarding behaviors and the accompanying sensations of pleasure - Mesocorticolimbic System
What is the pathway of the Mesocorticolimbic System and what Neurotransmitter is involved?
Ventral Tegmental Area (VTA) contains neurons that produce dopamine and whose axons project to the Prefrontal Cortex, Nucleus Accumbens, and Hippocampus
Which area of the Mesocortioclimbic System is involved in the feeling of subjective pleasure?
Nucleus Accumbens
Which area of the Mesocortioclimbic System is involved in learned association between rewarding feeling and specific stimuli?
Hippocampus
Which area of the Mesocortioclimbic System is involved in the cognitive control necessary to seek or avoid the rewarding stimulus?
Prefrontal Cortex
How is dopamine release in the Reward system used as a teaching signal?
Rewarding stimuli lead to encoding of associated features of the stimuli - the more we experience the stimuli the stronger these associations get and eventually turn into cues and can trigger an expectation which produces increase in DA release
What is the purpose of the Reward System?
Designed to motivate animals to engage in life-sustaining endeavors such as reproducing, eating, and maintaining social relationships
What is the effect of drugs on the mesocorticolimbic system?
Supraphysiological dopamine release in reward system leading to over-prioritization of behaviors associated with drug
What is cocaine?
A CNS stimulant which produces an increase in neural and behavioral activity
Highly addictive
Many physiological and psychological effects of cocaine resemble what happens when which nervous system is activated?
Sympathetic Nervous System
How does Cocaine effect dopamine at the synapse?
Cocaine blocks dopamine reuptake transporters preventing the reuptake of dopamine and allowing it to accumulate in the synapse leading to over-stimulation of the mesocorticolimbic system
What compensatory adaptations are made to compensate for excess dopamine caused by cocaine?
- Some dopamine receptors are removed from the postsynaptic membrane
- Dopamine release from presynaptic terminal is reduced
What is Anhedonia?
Inability to experience pleasure
