Psyc 211 Drug Abuse

Front 1

Why are drugs inhaled or ivs more common and addictive?

Back 1

the response or act of taking the drug will be positively reinforced immediately , the effect of any conditioning it stronger if the reinforcement occurs directly after
gives 'rush'

Front 2

Negative Reinforcement and Drug Use

Back 2

- Negative reinforcement increases the frequency of behaviour because of the removal of an aversive stimulus. ie taking another shot to reduce withdrawl symptoms
thus, Positive reinforcement provokes drug taking in the first place but negative reinforcement ensures that withdrawal effects go away.

Front 3

Tolerance vs Withdrawl

Back 3

- tolerance: a decreased sensitivity to the drug due to continued use.
- withdrawal symptoms: opposite effects of the drug itself when the person stops taking the drug.

Front 4

why is it called kicking the habit

Back 4

because people in rehab lose control of limbs often

Front 5

Incentive Salience

Back 5

When an addictive drug activates the mesolimbic dopaminergic system, it gives incentive salience to the stimuli that are present at the time of drug taking. This elicits cravings when around these stimuli

Front 6

Reinstatement and Mesolimbic System (what happens if you block dopamine in the nucleus accumbens?)

Back 6

Addictive drugs (e.g. PCP, cannabis, amphetamine, cocaine, etc) trigger the release of dopamine in the nucleus accumbens (White, 1996).
- If dopamine transmission is blocked in the nucleus accumbens, a “free” shot of drug will NOT reinstate lever press responses

Front 7

Reinstatement and Prefrontal Cortex

Back 7

Activation of the prefrontal cortex is directly related to craving. increases with craving. if you give yogita a chocolate her PFC will activate but long term users result in damage to PFC and reduces its activity- prefrontal cortes becomes less activated during PFC tests

Front 8

Gray Matter in Sciz and Alcoholics

Back 8

Abnormalities in prefrontal cortex may be a common factor in schizophrenia and substance abuse. There is a reduced prefrontal gray matter

Front 9

Opiates, receptors

Back 9

-have analgesic effects (relief from pain
- The μ (mu) and δ (delta) receptors are responsible for reinforcement and analgesia, stimulation of K kappa receptors has adverse effects
- if you knockout the μ (mu) receptor inmice, they become insensitive to the reinforcing and analgesic effects of morphine- dont show reduced pain or withdrawal

Front 10

What causes the reinforcing effects of Opiates?

Back 10

activation of neurons in the mesolimbic dopaminergic system and release of dopamine in the nucleus accumbens.
BUT 6-OHDA (6-hydroxydopamine) lesions of the nucleus accumbens disrupts lever pressing of rats for injections of cocaine but has NO effect for injections of heroin. (must be other mechanisms that facilitate heroin taking)

Front 11

Cocaine vs Amphetamine

Back 11

-cocaine binds with and deactivates dopamine transporter proteins thereby blocking reuptake of dopamine like a DRI
- amphetamine stimulates the release of dopamine, even at nor epinephrine sites

Front 12

Primary sites of action of Alcohol

Back 12

an indirect agonist at
the GABAA receptor and an indirect antagonist at the NMDA receptor. Both actions trigger apoptosis (cell death).

Front 13

Stimulant abuser long term brain effects

Back 13

Prior methamphetamine abusers show a decrease in the number of dopamine transporters in the striatum despite having abstained from the drug for 3 years
- stimulant abusers show an increase risk of parkinsons as they grow older!

Front 14

Nicotine- stimulates what, increases what?, found where

Back 14

• Nicotine stimulates nicotinic acetylcholine receptors.
• It also stimulates the mesolimbic pathway and causes dopamine release in the nucleus accumbens
Injections of nicotine increase dopamine concentration in nucleus accumbens.
Nicotine receptors are found in both the VTA and nucleus accumbens.

Front 15

explain how we lose our inhibitions with alcohol

Back 15

Alcohol releases the punishing effects of aversive stimuli.
- e.g. if a lever press leads to an electric shock, the rat will stop lever pressing.
- If rat is given alcohol, it will start lever pressing again (i.e. it increases punished responding).

Front 16

Canabis, cannabinoids

Back 16

High doses of cannabis impair psychological functioning, especially memory.
- the hippocampus releases endogenous cannabinoids.
- Like other drugs, cannabis stimulates release of dopamine in the nucleus accumbens.

Front 17

Early reinforcing behaviour vs later habitual behaviour

Back 17

early reinforcing drug taking behaviour takes place in ventral striatum, but the changes that make behaviours habitual takes place in the dorsal striatum. ventral striatum projects to VTA which sends reinforcing signals to dorsal striatum

Front 18

D1 vs D2

Back 18

in addicts we see increases in D1 receptors which excite and facilitate behaviour and decreases in D2 which inhibit

Front 19

Orexin and MCH

Back 19

- play big role in reinforcing effects of drugs.
- Administering orexin in VTA can reinstate drug seeking behaviour that was previously extinguished and blocking orexin removed drug seeking elicited by cues.
- Administering MCH reduced effectiveness of drug or drug related cues

Front 20

Dorsal Anterior Cingulate Cortex and reinstatement

Back 20

nhibition of DORSAL ANTERIOR CINGULATE CORTEX which has excitatory connections with nucleus accumbens, when in hibited prevents the reinstatement of a response, so this area plays a role in craving.

Front 21

activation of vmPFC

Back 21

- vmPFC plays a role in action suppression
- activation of it inhibits responses to cues

Front 22

CRH

Back 22

- peptide, plays a role in craving and stress
- infusion of CRH to VTA causes relapse and blocking it blocks reinstatement by stress

Front 23

rats separated from mother or socially stressed were more likely to...

Back 23

self administer drug

Front 24

Naloxone

Back 24

blocks u opiate receptors; antagonizes the reinforcing and sedative effects of opiates

Front 25

why do pregnant women who abuse opiates have addicted babies

Back 25

opiates easily cross the blood brain barrier

Front 26

Antagonist- precipitated Withdrawl; most sensitive sites

Back 26

-Sudden withdrawal from longterm use caused by cessation of drug and administration of an antagonistic drug
-LC, and then PAG- thus these places play role in withdrawl symptoms

Front 27

nicotine receptors are found___ but activation of receptors ___ seems to cause reinforcing nicotine

Back 27

VTA and nucleus accumbens; VTA

Front 28

what seems to decrease reinforcing effects of nicotine

Back 28

-blocking CB1 canabis receptors.... Craving for both food and nicotine is inhanced by release of endocanabinoids in the brain, which then increases MCH and orexin
- lesions to insula

Front 29

Medial Habenula- Interpenduncular Nucleus Pathway

Back 29

contains nicotinic Ach receptors with alpha 5 subunit. Inhibits the reinforcing effects of nicotine on the body naturally

Front 30

If you block dopamine pathways in alcoholics; give them Naltrxone...

Back 30

they drink less, they dont find pleasure in taste or act of drinking

Front 31

Acamprostate

Back 31

NMDA receptor antagonist, used for seizures and alcoholism

Front 32

Ligands to CB1 receptor

Back 32

2-AG, ANANDAMIDE

Front 33

Buprenophine

Back 33

therapeutic drug for opiate addiction

Front 34

Rimonbant

Back 34

drug that blocks CB1 receptors and is effective in helping smokers quit

Front 35

Deep brain stimulation

Back 35

deep brian stimulation especially of the STN or NAC are also promising for drug addiction fixes