W8: Are we in control while we are intoxicated?

Question 1

1) Outline the cog psy methods used to examine the influence of intoxication on cognition
2) To examine how such evidence can be used to influence policy

Answer 1

purpose!

Question 2

Can we be accounted for our actions when intoxicated?

Answer 2

Current law:
(S6,7)
lower max penalty for the crime committed

Question 3

Extention to Psychotic symptoms:

Why?

Answer 3

symptoms may be part of an intoxication syndrome, and resolve rapidly with the excretion of the psychotogenic (that is, psychosis-causing) substance from the body.

substance induced psychosis is used in the diagnostic classification schemes employed in mental health to describe such transient disorders.

It is usually long term, especially psychotic illness, -> long going even in even in the absence of ongoing substance use. furthermore, a person with an established psychotic illness may engage in substance abuse, which appears to precipitate psychotic relapses.

Question 4

Meth Use and Violent Behaviour:

Animal study

Answer 4

Acute doses in animals have inconsistently produced violent behaviour,

low to moderate doses appear to augment aggressive responses,

but the effects are not consistent across species or paradigms

Chronic methamphetamine exposure in animal studies (Sokolov and colleagues) has consistently demonstrated increased aggression and fighting behaviour

Question 5

Meth Use and Violent Behaviour:
Animal study
confound

Answer 5

confounded by the acute effects of meth on increased vigilance and psychomotor behaviour

Question 6

Acute doses of dextro-amphetamine, which is an oral medication used to treat narcolepsy and other conditions, show no increases in aggression

Answer 6

Increased talking, motor activity, anorexia, ‘friendliness’ but no acute or chronic increases in aggression

Chronic use has been prescribed to successfully treat aggressive behaviour in children with ADHD

Question 7

opioid withdrawal

Answer 7

Consistently associated in animal experiments and human observational studies with increased aggression

Question 8

60+% of heavy chronic Meth users report problems with aggression and problems controlling violent behaviour

Answer 8

Australian data indicates that prevalence of violent crime amongst regular Meth users is comparable to other illicit drug using groups (McKetin et al, 2005)

Question 9

Intoxication and Crime:

NSW Sentencing Council 2009 – Sentencing for Alcohol-related violence

Answer 9

Almost half of assault offences and three quarters of offensive behaviour incidents involve intoxication
A review of crime statistics from 11 countries, 62% of offenders convicted of a violent crime had been consuming alcohol shortly before committing the crime – Murdoch et al. 1990
Alcohol was more than twice as likely to be a contributing factor to violent crimes, compared to non-violent crimes
The magnitude of violence was related to the magnitude of consumption

Question 10

Does Intoxication increase aggression?

Links: (4)

Answer 10

1) Psychomotor stimulant effects
2) Interrupted threat detection
3) Alterations of the pain system
4) Alterations of cognition

Question 11

Psychomotor stimulant effects

Answer 11

Euphoria accompanying intoxication is rewarding, which is accompanied by increases in nervous system stimulation
1) increased BP, HR, respiration

2) Also increase sensation seeking, approach behaviours
3) Confrontational and provocative behaviours

Question 12

Interrupted threat detection

Answer 12

Alcohol alleviate subjective feelings of stress, (upregulation of GABA in the brain)

Intoxication can result in diminishing appropriate levels of stress and or fear

Other drugs that have an anxiolytic effect (e.g., cannabis) but are not linked to violence, also have a CNS depressant effect
(combi effect)

Question 13

Measures of aggression

Answer 13

S17-19

Question 14

Influence of sub. Intixication,
…..
Taylor Aggression paradigm

Answer 14

Subjects are placed in a situation where electric shocks are received from and administered to a fictitious opponent during a competitive reaction-time task

Physical aggression is indexed as the intensity of shocks administered to the opponent

Given that aggression is highly related to provocation, the TAP has low and high provocation conditions

Opponents are introduced at the beginning of the experiment and sit opposite throughout, they are same gender and race

Pain thresholds are individually assessed and factored into shock intensity

Question 15

Results from study (card 15)

Answer 15

Alcohol significantly increased aggressive behaviour in comparison to the placebo, for men but not women

The effect of alcohol expectancies on aggression in men was rendered nonsignificant when statistically controlling for dispositional aggressivity

alcohol may amplify aggression

Question 16

Four pharmacological links between intoxication and aggression

Alterations of the pain system

Answer 16

In the descending limb of alcohol intoxication pain sensitivity is decreased

Question 17

Four pharmacological links between intoxication and aggression

Alterations of the pain system

Answer 17

In the descending limb of alcohol intoxication pain sensitivity is decreased

Question 18

Four pharmacological links between intoxication and aggression

Alterations of the pain system:
The paradox

Answer 18

In the ascending limb of intoxication humans sensitivity to pain increases (Gustafson, 1985, Gray, 1982)

The effect of alcohol is therefore thought to be paradoxical

Question 19

Four pharmacological links between intoxication and aggression

Alterations of the pain system:
The paradox

Answer 19

In the ascending limb of intoxication humans sensitivity to pain increases (Gustafson, 1985, Gray, 1982)

The effect of alcohol is therefore thought to be paradoxical

Question 20

Four pharmacological links between intoxication and aggression

Alterations of cognition

Answer 20

Alcohol is known to interfere with many aspects of cognition, but the studies to understand the nature of this relationship have only been conducted in the last 20 years

Early research examined a broad range of tests such as reaction time, visual and auditory acuity, hand-eye co-ordination, gross body movement, short term memory

Threshold or effective blood alcohol concentration (BAC) -> majority of subjects displayed a reliable impairment for a given task
(as change is usually relative showing this is important)

Question 21

Four pharmacological links between intoxication and aggression

Alterations of cognition
Study 1:
REview: results

Holloway (1995), Kruger (1992), Mitchell (1985)

Answer 21

Reviews indicate that most behaviours experimentally tested have a threshold BAC of 0.08% -> simple reaction time

Higher-order cognitive functions, (decision-making, judgement, memory) -> BAC threshold of 0.06%

More complex divided attention tasks that (dual task), BAC threshold of 0.05%

Question 22

Processing speed

Answer 22

Simple reaction time tasks showed intoxication slowed behavioural responses to stimuli

1) Motor issue
2) Flicker fusion task
3) Subtraction task (count down from 100 each time - 7)

Question 23

2) Flicker fusion task

Answer 23

Strobe-like flashing light that increases the ‘flicker’ frequency until it gives the impression of a continuous stream of light, from a flicker to a fusion

With alcohol consumption the point at which subjects report the flicker to fusion transition is earlier -> Attributed to a slowing of neural processing somewhere in the visual processing system between the retina and visual cortex