Neuroscience has made great strides which now provide new ideas about the development of the brain. New discoveries confirm scientifically that the teen years are a period for transition (Adolescence, Brain Development and Legal Culpability, Juvenile Justice Center)
Impressive changes are believed to occur in the brain in the second decade of life. Some time back, it was believed that the brain was fully formed by the age of two. The maximum development occurs in utero and then in adolescence. An early adolescent is different from a late adolescent in physiology, anatomy and biochemistry where the brain is concerned. Adolescence is a crossroad of changes, especially in the frontal lobe. The frontal lobe is “involved in behavioral facets germane to many aspects of criminal culpability,” (Adolescence, Brain Development and Legal Culpability, Juvenile Justice Center). This area is the seat of higher functions like learning and socialization. The pre-frontal cortex is known as the executive of the brain. Functions like priority setting, organization of plans and ideas, devising strategies, impulse control and attention skills are organized in this pre-frontal area which matures towards the last phases of brain development.
Just before puberty, several new neural connections begin to develop. Some are lost in “use-it-or-lose-it pruning” (Adolescence, Brain Development and Legal Culpability, Juvenile Justice Center). The unnecessary connections are lost and the brain becomes an efficient system. Pruning leads to elimination of weaker fibers and leaves behind the stronger cellular connections. Neural circuits become a bigger and more efficient network with the ability to perform many tasks simultaneously and more efficiently. The strengthening of the connections occurs in the areas of brain that subserve self-control, emotions, judgment, organization, multitasking and goal-directed behaviors. The maturation of the circuits is marked by myelinization which speeds up the transmission. The cells communicate faster and multiple stimuli are integrated simultaneously through the myelin sheaths (NIMH, 2001 as cited in Herman, 2005). The children have more of the unmyelinated nerve fibers. As more myelinization occurs, it becomes more difficult to recover from nerve injury and the ability for new learning decreases (Wallis, 2004 as cited in Herman, 2005). The neurotransmitter, chemical messenger dopamine, promotes the learning in response to reward. During adolescence this neurotransmitter increases its action on the pre-frontal cortex. This enhances the maturity level of the adolescent and his impulse control. Ideas become reinforced and valued during adolescence.
The stress and strain of adolescence is influenced by the hormones which are responsible for the mood swings, wavering judgments and the difficult responses to the circulating oestrogens and progesterones. Abstract thinking which is the highest level of reasoning is formed between the ages of 11 -1 4 (Hockenbury, 2003 as cited in Herman, 2005). The brain development in early adolescence has three processes (proliferation, pruning and myelinization (Spano, 2003 as cited in Herman, 2005). Grey matter or unmyelinated cells are thought to increase and peak in adolescence at age of 11 in girls and 12 for boys. This increase occurs as a response to stimuli (Wallis, 2004, p. 59 as cited in Herman, 2005).
Modern research is focusing on the selective pruning that is seen in the process. Factors include the activities and disciplines that limit the pruning (Adolescence, Brain Development and Legal Culpability, Juvenile Justice Center). The influence of genes and hormones on the pruning process is also being studied. Inefficient, appropriate or overzealous pruning may affect the process. The behaviors that cause “poor decision making, reckless behavior, rule breaking, emotional outbursts, lesser organizational abilities and lack of processing of the abstract” can occur when pruning processes are hindered.
Alcohol abuse during the pruning process in adolescence increases the person’s susceptibility to alcohol damage (Spear, 2002 as cited in Herman, 2005). The results could be impairment in memory and learning. Binge drinking was more associated with those who indulged in alcohol abuse in adolescence. The tendency for dependency also increased. Repeated exposure during the teen years made the children more prone to alcohol induced impairments in their later adult life.
A link has been found between deficiencies of essential fatty acids in children who have delayed myelinization. The efficiency of myelinization is also found disturbed (Wainswright, 2002 as cited in Herman, 2005). The impact of diet and environmental factors involved in myelinization and thereby the effect on the brain and cognitive development are the recent focuses of research.
Brain Development
The processes of pruning, proliferation and myelinization develop in a back to front manner in the brain (Adolescence, Brain Development and Legal Culpability, Juvemile Justice Center). The cerebellum matures first. Cerebellar functions include muscular coordination, rudimentary senses and early thought processes. Physical fine and gross motor developments increase with age. The amygdala at the rear end of the brain matures at adolescence to control emotional processes. Fear and rage develop at the teen age due to the amygdala maturation. The adolescents have a gush of these emotions due to the speedy development at this age (NIMH, 2001 as cited in Herman, 2005). Then the midbrain including the basal ganglia and corpus callosum undergoes maturation and myelinization. The basal ganglia which is termed the “secretary” organizes the brain and keeps it on time and on task (Wallis, 2004 as cited in Herman, 2005). Priority setting and fine-tuning fine motor functions are developed in the teen age. Gender differences are seen in boys and girls due to the basal ganglia being larger in the females. The corpus callosum is involved with creativity and critical thinking and tasks like problem solving and decision making.
The last portion of the brain to mature is the front of the brain or pre-fontal cortex and may last till the age of 20 years. The frontal lobe undergoes more change in adolescence than in any other period (Adolescence, Brain Development and Legal Culpability, Juvenile Justice Center). The functions of sober second thought; rational and executive functions are performed here (Wallis, 2004, p. 61 as cited in Herman, 2005). The skills of organizing thoughts, weighing consequences, assuming responsibility and interpreting emotions are developed here. The skill of formal operational thinking may be developed when well into adulthood. Some Neo-Pagetian researchers believe that half of the adolescents remain in a transitional phase thereby in the concrete operational thinking. New implications and the application of cognitive theory are developed. Teens who have not developed the pre-frontal cortex, use the temporal lobe to interpret stimuli and act upon it. Emotional reasoning may not be a good function by them. Teens find it difficult to be skilled in emotional reasoning.
Hormones also influence the brain development of teenagers (Walker, 2002 as cited in Herman, 2005). Serotonin governs mood and creates control of emotions. Mental health issues are influenced by the oestrogen and progesterone and may produce features of schizophrenia, depression and bipolar disorder. Mood swings and sensation seeking are both due to the inciting of the brain’s emotional center at the limbic system. Dopamine, a neurotransmitter, causes risky behaviors and novelty seeking. It produces pre-behavior thoughts and the tendency to go into certain behaviors. Dopamine has been tried in Attention Deficit Hyperactivity Disorder in children and adults. It assists the person to inhibit behavior, to provide a motivation to act and to seek meaningful rewards. Fluctuations in the dopamine levels could influence the teenage behavior and produce susceptibility to addictive behaviors (Spear, 2002 as cited in Herman, 2005). Teenagers have the tendency to cultivate sensation-seeking behaviors which prompt them to take risks but do not know when to stop. The cognitive controls are not in place yet. They do not know how to harness their feelings (Wallis, 2004 as cited in Herman, 2005). This is because the nucleus acumbens of the frontal cortex fails to be well developed. The cognitive power is not seen in teenagers and they cannot have delayed gratification or predict far-reaching conclusions. They allow themselves to reach high levels of excitement. Unprotected sexual activity is a normal reaction in teenagers as the control mechanism is different. Melatonin from the pineal gland influences the slow shutting down of the body and inducing of sleep. Teenagers are very tired usually due to more exertions and difficulty to sleep sometimes. New imaging techniques allow the examination of the normal brains as well as diseased ones all through life. Functional MRIs allow the visualisation of the brain functions and structure.
Legal culpability
The great strides in medicine have allowed us new imaging systems that not only show the anatomical structure but also the functions involved along with the change in energy used.
If a particular brain structure is immature, the functions are also immature. Previously it was thought that the young were in a position to adjust. The harsher view is now more prevalent whereby the juveniles are believed to commit serious crimes because of their brain immaturity.
In the eighteenth century, children as young as 6 years were criminally culpable just like adults (Spinks, 2005). In 1825 the New York House of refugees was founded by the Society for the Prevention of Juvenile Delinquency. Many other juvenile institutions had a significant educational and rehabilitative function. The root cause was believed to be lack of moral education which was addressed in these institutions.
The first juvenile court was established in 1899 in Cook county (Spinks, 2005). The State was to be alert to the interests of the public as well as watch over the offender. The juvenile court had a flexible attitude and aimed at rehabilitation. Punishment was not the aim. It was argued by some that rehabilitation was not ensured. In the 1960s and 1970s The Judges of US Supreme Court decided that children were not receiving the attention they needed. The process was to be better defined and the children were to be protected better. Formal hearings would decide whether they would be waived to the criminal courts, when they had to be protected against self incrimination, to be represented by counsel when needed and upholding the judicial standard of proving the crime without a reason for doubt (Spinks, 2000). In the 1970s, cruelty was the treatment meted out to juvenile offenders. In 1974, the Juvenile Justice and Deliquency Prevention Act was passed. Deinstitutionalizing of status offenders and separation of juvenile offenders from adult offenders was followed. In 1980, an Amendment said juveniles could never be placed in an adult cell. Community based programs hoped to change the situation where the stoppage of institutionalization was aimed at. In the 1970s , rising violent crimes forced the public outcry demanding the “get tough approach” (Spinks, 2000). The conservative trend with more punitive laws continued till the 1990s. The laws passed allowed the juveniles to be tried in court like adults, where sentencing options were expanded, confidentiality provisions were modified and the victim’s role was increased. Now again the offenders are being treated like adults.
That juvenile offenders could have been influenced by the immaturity in their brain development for turning to crime is a good base for prevention of the crime itself. The adolescents need to be taken in hand just prior to the vulnerable age and given the kind of support that they need in order to stop turning to crime. Evidence has been found that participation in school and community based activities is associated with indicators of positive development.
Psychiatric and legal organizations are of the opinion that teenagers often make impulsive decisions and that their brain has not attained the adult level (Bower, 2004). Teenage killers thereby cannot be held responsible for their actions. Subjecting them to capital punishment would be equivalent to a violation of the constitutional amendment which is for the protection of the citizens from cruel punishment. They have protested against the use of the death penalty for adolescents who have committed murder (Bower, 2004). The biological perspective has been highlighted to say that an anxious adolescent is more likely to pull the trigger in a stressed condition than an adult in the same situation. They therefore have reduced legal culpability for their actions and do not deserve the extreme punishment Amnesty International has found that 2225 prisoners are serving life sentences without parole for crimes committed in their teenage life (Hubner, 2006). Statistics show that more prisoners belong to the minority groups. The time has come for all psychiatrists, judicial authorities and human rights activists to put their heads together to find a solution to curb our young from crimes and to ensure that the teenagers are not unduly penalized due to the lack of information and incapability of the authorities who cannot help them. New imaging techniques like fMRI are there for help.
References:
Adolescence, Brain Development and Legal Culpability, Juvenile Justice Center, American Bar Association, January, 2004.
Bower, B. (2004) Teen Brains on Trial: The science of neural development tangles with the juvenile death penalty. Science News Online, Vol. 165, No. 19.
Herman, J. (2005). The Teen Brain as a Work in Progress: Implications for Paediatric Nurses. Paediatric Nurse, Vol. 31 (2). Pgs 144-148.
Hubner, J. Discarded lives: Children sentenced to Life without parole, Amnesty International magazine, Spring 2006.
Spinks, S. (2000). Adolescent brains are a work in progress. Nature, Vol. 404.