You may not know much about the prefrontal cortex or think that much about brain development as a whole but the next time you find yourself screaming “STOP!” or asking exasperatedly “why did you do that?!” as your child shrugs their shoulders, you are directly experiencing the effects of dealing with someone with immature frontal lobes.
The brain develops back to front so the prefrontal cortex is the last bit of the brain to fully develop – it isn’t fully mature until about age 25. Given it’s in control of our ability to plan, focus attention, control impulses and predict consequences (“If I do A then B will happen”), it perhaps becomes easier to understand why a 6 year old doesn’t see what all the fuss is about when they want to jump off a high wall onto some concrete. They simply aren’t able to inhibit inappropriate behaviour.
The prefrontal cortex grows in spurts. Between the ages of 2 and 7 children develop memory and imagination, they start to understand things symbolically and ideas of the past and future. Between 3 and 5 children are developing cognitive flexibility, this means they can find it hard to switch tasks and sometimes aren’t able to do it at all. Between the ages of 5 and 8 there’s a big growth spurt in the prefrontal cortex, which results in vast improvements in working memory, planning, selective attention and inhibition. Between the ages of 7 and 11 children start to realise not everyone has the same beliefs or feelings as them.
During the teenage years the prefrontal cortex also changes dramatically. There’s another growth spurt around 11-12 years and during the teenage years their brain changes yet again, getting rid of connections that aren’t used and strengthening ones that are. So at this point the brain is particularly malleable and the environment is key as the brain uses a sort of ‘use it or lose it’ principle – skills that are used frequently will be reinforced, whilst those that aren’t will die off. The prefrontal cortex continues to develop during this time and this means teenagers are still learning to take on the perspectives of others and might still rely on their emotions and impulses (the limbic system) more than logic and reason (the prefrontal cortex) leading to risky behaviour – so they might well know they shouldn’t jump off that high wall on to the concrete below but do it anyway.
So the brain goes on developing from childhood into young adulthood and is shaped by the environment, which reinforces or reduces the likelihood of using certain skills, and the behaviours of other people. Teenagers and particularly children learn from watching others – this means they will be watching how you regulate your own behaviours and emotions. If you start to notice your own emotional state and how you deal with it (are you jumping off any ‘high walls’ of your own?) then you can also start to demonstrate impulse control which will in turn help your kids develop theirs.