Remember to reference this as evidence in your submission to the Scottish government's proposal of GRA reform.
www.scottishsentencingcouncil.org.uk/media/2044/20200219-ssc-cognitive-maturity-literature-review.pdf
The conclusion is worth reading.
- Conclusion
This report has synthesised recent neurological and neuropsychological evidence pertaining to the age at which adolescents achieve cognitive maturity. In doing so it has outlined the development of neurocognitive functions and the stages at which they occur, discussed factors that have the potential to temporarily or permanently disrupt the typical developmental trajectory, and examined
the links between cognitive and emotional maturity. In doing so we have endeavoured to answer the following aims:
To identify evidence that emotional maturity is linked to maturation of the brain, and of the age at which the brain is fully developed.
The advancement of neuroimaging methods has played a key role in our understanding of adolescent cognitive development. MRI studies in particular have demonstrated that the brain remains in an active state of development until between approximately 25 and 30 years of age.
During this developmental period, an immature prefrontal cortex, and consequent dysfunctional cognitive control over phylogenically older emotion and reward-related regions, are suggested to be
responsible for the normative risk-taking behaviour characteristic of the adolescent period; and to contribute to difficulties in self-regulation (5,8). In short, immaturity of cognitive regions along with overactivation of emotion and reward-related regions contributes to adolescents finding it difficult to think rationally and critically before making complex decisions (9). Pubertal onset is reported to trigger this increased behavioural responsiveness to emotionally salient stimuli, again reflected in aberrant fronto-limbic functional connectivity (5,8).
To identify evidence that continuing development of the brain during adolescence and young adulthood means that young people have less impulse control, ability to plan and make rational decisions, and greater susceptibility to negative influences and peer pressure.
The brain’s continued maturation during adolescence and into early adulthood limits the functional abilities of young people, impacting their capacity to control their behaviour. Most affected are those skills that form the executive functions (including the ability to plan, control impulses and pay attention), which are located in the last region of the brain to achieve maturity, the prefrontal cortex, meaning that adolescents are unable to call upon them reliably. Concurrently, a rise in dopamine is associated with an increased sensitivity to incentives and rewards, particularly those associated with short term gain, peaking between the ages of 14 and 16 years of age. Brain regions associated with emotional responses become more active and sensation-seeking is observed to increase. Occurring together as they do, it is the immaturity of the executive functions, coupled with their emotional context, that impairs decision-making in the presence of rewards, making it difficult for adolescents to ‘override’ their drive towards short term gratification. This is particularly the case in males, where, in comparison to females, higher levels of sensation-seeking and lower levels of impulse control are observed (262). The presence of peers has also been observed to exert an influence on decision making, although the mechanism for this remains unclear.
To identify evidence around any factors which inhibit, either temporarily or permanently, cognitive maturation including, but not limited to, adverse childhood experiences (ACEs) and traumatic head injuries.
The ongoing development of the brain during adolescence increases its vulnerability to factors that may slow, or permanently disrupt cognitive maturation. Findings have evidenced that factors including traumatic brain injury, alcohol and substance use, psychological and neurodevelopmental disorders, and adverse childhood experiences, contribute to abnormal cognitive maturation and functioning. Adverse experiences are a particularly potent and significant risk factor as these also compound and increase the risk and vulnerability to develop significant mental health problems, accumulate further stressors and adverse experiences, and affect key factors of resilience and cooping, such as the abilities to mentalise, emotion regulate and utilise support.
.....
.....
7.2 Application in Judicial Contexts
The neurobiological and cognitive developmental trajectories associated with cognitive maturation are non-linear, and differ between individuals, limiting our ability to definitively pinpoint the beginning and end of cognitive maturation. There is however converging evidence that this process continues into the mid to late twenties, an age range typically considered adult rather than adolescent and that we should consider biological, rather than chronological age. Most striking is that the last region to develop is that which provides the foundation for those functions most likely to be relevant in a judicial context, the executive functions. Significantly, evidence supports theoretical models that position poor decision-making and increased risk-taking in adolescence as the result of typical maturational processes rather than solely reflective of preference or personality.
It would appear therefore that the consideration of culpability, and by extension sentencing, in both adolescents and young adults should include due regard to their cognitive maturity. More difficult will be attempts to support such deliberations with assessments of cognitive maturity on an individual level. Currently, the widespread use of imaging is both impractical and unlikely to be helpful given the variability between individuals but, as the number of epidemiological studies mapping normal brain development increase, it may in the future be possible to develop growth curves similar to those used routinely for height and weight. The comparison of offenders’ performance on psychometric measures where normative data exists to illustrate typical functioning
in both adolescents and adults is perhaps feasible in a minority of more serious cases but the measurement of many aspects of cognitive maturity may prove elusive.
It follows therefore that consideration of adolescent cognitive development is highly relevant to the judicial system given the necessity to:
i. Ensure an adolescent’s ability to engage with the court process and their fitness to
plead (15)
ii. Consider an adolescent’s culpability, relative to their cognitive maturity and linked ability, during sentencing
iii. Consider sentencing decisions with reference to their potential to expose an
individual to additional contextual and behavioural factors which may inhibit or
disrupt typical cognitive development.