Alcohol and Substance use- Lecture 4 Flashcards
Bio Link between Alcohol use and adolesence
Due to brain changes, characterised by sexual maturation and establishment of identity
Brain changes in Adolescents
Pruning in BASAL GANGLIA and PREFRONTAL AREA:
-Removes the excess of synapses, that form unnecessary connections, whilst refining the neural connections that are frequently used (Carried out by Astrocytes in brain)
Myelination:
-Encasing neurons in myelin sheath which increases speed and efficiency of transmissions of action potentials
Klinberg (1999) Myelination
Found fibre tracts throughout the frontal cortex continue to myelin-ate into the second decade of life
Liston (2006)
Evidence of adolescent brain changes
improved myelination= performance better on a (a measure of inhibition). Also better performance with age.
Potentially, as myelination has not complete, behaviour may be less inhibited
Reward system
Fuster (2002)
Pruning and myelination actually begin earlier in reward system- so are relatively mature
-May lead to increased reward seeking
Steinberg (2010)
Dual systems model of Adolescent Risk taking
- Reward seeking begins earlier
- Impulsivity is yet to be controlled by the cognitive control system
- Interaction between these two leads to increase of risk taking in adolescence.
Impulsivity as a trait
Considered a dimension of personality as early as Eysenck (1956)
Trait impulsivity during adolescence
Steinberg et al. (2008)- declines from age of 10 to 30
sensation seeking increased from 10 to 15 then declined
Casey & Jones (2010)
Found sensation seeking to peak when the difference in maturity between reward centres of the brain and the development of frontal areas was the greatest.
UPPS
Whiteside and Lynam (2001)
A Factor Analysis on all commonly used measures of trait impulsivity Found these common categories Urgency Premeditation (lack of) Perseverance (lack of) Sensation Seeking
Stautz & Cooper (2013)
UPPS and alcohol
Meta analysis on the relation between UPPS traits and alcohol use among adolescents.
All UPPS traits associated with increased alcohol consumption and ‘problematic’ use.
Behavioural measures of Impulsivity- Impulsive choice
Some individuals prefer small immediate rewards over larger long term rewards- known as Delay Discounting (Petry, 2001).
Desire for short term small rewards> more impulsive
Petry, (2001)
DELAY DISCOUNTING
Behavioural measures of Impulsivity- Impulsive action
Inhibiting a pre-potent response to a task e.g: >Stroop task >Go/no go task >Flanker task
Impulsivity as a risk factor
Studies of substance abusers show impulsivity inhibition problems & predicting later substance abuse through impulsivity
Nigg et al. (2006)
Stop-signal performance predicted alcohol-related problems, and illicit drug use among adolescents
Fernie et al (2013)
Performance on stop signal task and delay discounting among 12-13 yr olds predicted alcohol use every six months across 2 years
Criticisms
Questioning research linking adolescents particularly to impulsivity
Most adolescents do not engage in physical aggression
Trembley et al. (2006)- as referenced later
Nagin & Tremblay (1999)
Those involved in aggressive behaviour at an early age showed a decline in this behaviour as they aged
-perhaps risky behaviour begins earlier
Mischel et al (2010)
Marshmallow test- impulsivity in children- linked to academic attainment
Review showed replication has confirmed findings of original.
More impulsive will attain less academically
Criticisms of Mischel (1970) Marshmallow test
- Small and highly selective sample
- Recent replication (Watts et al, 2018) found much smaller correlation between test and academic attainment
- Reduced when controlling for demographic factors
Early Stressors
Anda et al (2006); Middleebrooks & Audage (2008)
Early life stressors related to risky behaviour in adolescents
- Neglect
- Abuse
- Parental substance abuse
- Exposure to violence
Lovallo (2013)
Stress experience during early life leads to reduced stress reactivity in adulthood. ► Reduced stress reactivity accompanies a disinhibited behavioural style. ► Disinhibited behaviour can increase risk of substance abuse.
Trembley et al. (2006)
- Most children have had their ‘onset’ of physical aggression by the end of their second year after birth
- learned to inhibit physical aggression by school entry
Aggression in adolescence may be due to type-
>Childhood limited
>Life-course persistent
Romer (2010)
Adverse evidence linking neural activity to impulsivity
Little evidence linking neural development to increased impulsivity in adolescence
Cortical thinning 5-11 yrs due to important learning period (associated with improved vocabulary) and wrongly correlated with impulsivity
DeBellis et al (2008)
Adverse evidence linking neural activity to impulsivity
Myelination in some areas more advanced in youth with alcohol use disorder
Brain changes and early stressors
Brain changes may be in response to early life stressors- Volman et al. (2018)-
>personal early-life stressful events were associated with larger developmental reductions in grey matter volume
Interventions
Can be used to prevent early impulsivity that continues until adolescence
Petras et al (2008)
Interventions
Good behaviour game- long lasting effects on those who exhibit high rates of aggression and uncontrolled behaviour (19-21 yrs)
Romer et al (2010)
Interventions
Experience of regrettable consequences stemming from risk taking itself can be used to gain patience in delay discounting- reducing impulsivity
Spear (2009)
Interventions
Experiences in adolescence may serve to customise the maturing brain- > learn from mistakes and over time gain more control of actions
