Addiction

Question 1

Substance related disorders

Answer 1

Alcohol, Caffeine, Cannabis, Hallucinogen, Inhalant, Opioid, Sedative/hypnotic/anxiolytic, stimulant, tobacco

Question 2

Non substance related disorders

Answer 2

Gambling, others not included due to insufficient evidence to establish the diagnostic criteria

Question 3

Social networking addiction symptoms / criteria

Answer 3

neglect of personal life, mental preoccupation, escapism, mood modifying experiences, tolerance, and concealing the addictive behaviour,

Question 4

fMRI social networking and rewards

Answer 4

Ps working to win rewards in card games
Played together with a computer, an unknown person or a friend.
The same rewards were rated as most exciting when won with a friend.
Projects dopamine to the nucleus accumbens and medial prefrontal cortex
NA was most active when winning to a friend

Question 5

Neural response to likes

Answer 5

Meshi et al. 2013: nucleus accumbens of participants responded more when they received Likes rather than when observing others receiving Likes. Heaviest Facebook users showed the largest response.

Question 6

Media use and grey matter

Answer 6

Montag et al. 2017
The more time spent on Facebook, the less grey matter volume in the nucleus accumbens.

Question 7

Dopamine D2 receptors in an internet addict

Answer 7

found widespread drop-offs in dopamine D2 receptor availability in internet addicts throughout dopaminergic regions, including the nucleus accumbens

Question 8

Neural responses in gaming addictions

Answer 8

WOW (computer game) images specifically activated the medial frontal cortex and nucleus accumbens in people with gaming addictions
Suggests online gaming addiction is similar to that of cue-induced craving in substance dependence

Question 9

Grey matter changes in gaming addicts

Answer 9

Internet game addicts (10h/day for 3 yrs): grey matter volumes reduced in a number of areas correlated with length of time spent addicted - negative correlation

Question 10

Reward and punishment sensitivity in gambling addicts

Answer 10

Guessing task while in fMRI scanner: which of 2 cards is red (or black).
Internet addicts showed enhanced frontal activity during gains, reduced anterior cingulate during losses.
Enhanced reward sensitivity and decreased loss sensitivity

Question 11

Treatment for gaming addiction - drugs

Answer 11

Starcraft addicts (>7h/day) showed higher brain activation in dorsolateral prefrontal cortex with game cues
After 6 weeks on Bupropion (also used to help people stop smoking), craving for game play and cue-induced brain activity in the dorsolateral prefrontal cortex decreased.
Game play time down more than a third

Question 12

Neurological effects of gambling addictions

Answer 12

fMRI study of pathological gamblers
normal response to happy or sad videos, but increased activity to gambling videos in regions associated with reward reactivity (nucleus accumbens)

presented Sections of nature scenes (Baseline) or gambling scenes to controls vs. pathological gamblers
Gamblers self-reported high levels of craving, and enhanced frontal cortex activity

Question 13

Dopamine release in gambling addicts

Answer 13

measured striatal dopamine in pathological gamblers when carrying out either a control task or a slot-machine task
increased accumbens dopamine release on a gambling task in pathological gamblers
positive correlation between severity of gambling issues and size of dopamine release.

Question 14

Alcohol addiction criteria

Answer 14

at least two of the following, occurring within a 12-month period:
A persistent desire or unsuccessful efforts to cut down or control alcohol use.
A great deal of time is spent in activities necessary to obtain alcohol, or recover from its effects.
Failure to fulfil major role obligations at work, school, or home.
Increased tolerance - need more for the same effect.
Withdrawal symptoms - brain produces ‘drug opposite’ effects

Question 15

Describe the mesolimbic dopamine system

Answer 15

Ventral tegmental area - Towards back of the brain
Projects towards nucleus accumbens (Mesoaccumbens dopamine projection)

Question 16

Simulation addiction in rats - electrical brain stimulation

Answer 16

Studies allowed rats to induce electrical current in the region of the mfb themselves - ‘intracranial self-stimulation’, or ICSS.
Rats were pressing lever hundreds of times, very rapidly, no breaks in lever pressing
Almost no break for 24 hours
simulates pathway taken in other addictions such as gambling

Question 17

Electrical brain stimulation in humans

Answer 17

ICSS can also be so reinforcing in humans that may ignore available food
The introduction of an attractive tray of food produced no break in responding, although the subject had been without food for 7 hours, was noted to glance repeatedly at the tray, and later indicated that he knew he could have stopped to eat if he wished.
Keep stimulating pathway rather than eating or taking a break

Question 18

Drug addiction and the nucleus accumbens

Answer 18

cocaine activates nucleus accumbens in humans
Also activated when participants are craving cocaine e.g watching a video of someone taking cocaine

Question 19

Mesoaccumbens dopamine and rewards

Answer 19

More dopamine released in the accumbens, the ‘higher’ you feel

Question 20

Impact of chronic drug use on dopamine receptors

Answer 20

Reduced dopamine receptors in striatum of recently abstinent human cocaine addicts after 3 months
Same dose produces a lesser effect as the brain compensates

Question 21

Impact of smoking on accumbens dopamine receptors

Answer 21

smoking reduced both the number of D2 dopamine receptors, and methylphenidate-induced dopamine release

Question 22

Impact of chronic drug use on grey matter

Answer 22

Reduced frontal grey matter (neural cell bodies) volume in crack cocaine addicts in comparison with control participants
Addicts on average for 13 years

Methamphetamine addicts also showed reduced grey matter volume internally across large areas, e.g. cingulate gyrus, subgenual cortex and paralimbic belts that encapsulate the corpus callosum

Question 23

Pavlovian conditioning and dopamine in drug addicts

Answer 23

cocaine addicts shown videos of people taking cocaine. Dopaminergic response correlated with self-reported craving.

even just watching someone take cocain gave them a similar feeling to taking cocaine

Question 24

What causes drug addiction and cravings? - conditioning

Answer 24

They activate the mesoaccumbens dopamine projection, causing drug-associated stimuli to elicit a conditioned response

Re-exposure to drug-associated stimuli at a later date - perhaps months after the drug was last taken - activates memories of the drug experience itself, and hence craving for the drug.

Question 25

Pharmalogical treatments for drug addictions

Answer 25

Nicotine - nicotine patches/gum, ameliorate withdrawal symptoms and craving. Opiates: (morphine, heroin) - methadone, mild non-high inducing version of heroin. Prevents onset of withdrawal symptoms, and also craving Alcohol: ‘Antabuse’ (Disulfiram), inert until alcohol consumed, then induces nausea, dizziness etc Don’t address psychological aspects of addiction, don't stop cravings Martell et al. (2005) - gave cocaine-specific vaccine (TA-CD) to cocaine addicts, so cocaine will be recognised by the immune system and broken down quickly. Addicts showed dose-dependent reduction in relapse rates After 12 weeks, those on a high dose were free of cocaine

Question 26

Extinction therapy as a drug treatment

Answer 26

heroin addicts - cue exposure followed by extinction therapy erased craving response to drug cues. Stop responding to heroin related cues Repeated exposure to heroin cues - people talking about heroin, taking it, without pairing of the participant taking the drug Stop associating the cues with the reward However, response only changed in response to the videos in the lab - when they were back home, their response was the same as before the therapy