Professor Howard Sercombe, Strathclyde University
Well, nothing. Unless that is all you do. Unless it unbalances investment in development so there isn’t any money left for anything else.
The focus on the early years is a result of very effective lobbying based on recent developments in neuroscience, which found that the development of brain circuitry does not happen in a regular, linear way, but surges and levels off and surges again. If children’s learning environments are poor (or chaotic, or violent) while a surge is going on, this can have long term consequences for the way their brain works. The first three years, (and the period just before puberty) are surge years. Investing in children’s care and education in these periods just makes sense. And it should, all things being equal, cost less in the long term. This is the Early Years approach.
Actually, some of the information is not so recent. Early work on developmental windows indicated that there were fairly narrow periods in a child’s development when their brain is available for hardwiring certain functions, and if you miss that window, the opportunity is gone for ever. We now think that seriously underestimates the flexibility (the neuroscientists call it plasticity) of the human brain. It was based on experiments with blinded kittens and human beings are a bit different.
However, it isn’t the whole story. Certainly, the development of new brain circuits levels off around puberty. But there is also an interesting story about what happens in the brain in the teenage years.
The problem with the massive proliferation of circuitry in childhood is that it isn’t very efficient: a bit like having too many programs running on a computer. In the teenage years (roughly 14-23) the brain goes through a process of streamlining to make it more efficient. Two processes are involved in this. First, the brain stops using circuits that aren’t used very much: neuroscientists talk about this as ‘pruning’ or ‘editing’. As the old slogan goes, use it or lose it. Second, certain circuits are selected for special treatment to make them hundreds of times faster and cleaner. This involves coating the neural fibres with an insulating sheath made of a fatty material called myelin. Kind of like putting tarmac on a road.
We don’t yet know how circuits are selected for myelination, but it is likely to be a combination of genetics in strong interaction with the environment, especially the social environment. Different environments will dictate which genes are switched on, as well as impacting directly on brain structure. A logical guess is that the organism decides which circuits to keep or enhance and which ones to get rid of in response to its environment.
So. Investigating in magnificent circuitry through world-class learning environments for little kids seems a bit of a waste of time if teenagers’ environments are poor, neglectful, chaotic or hostile. It’s a bit like building a library collection in which you have the best librarians in the world in charge of acquisitions but culling and disposals decisions are done by the janitor. And he only likes books with pictures.
Two take-home points.
One, the early-years lobby has done a great job, but has probably over-stated the case a bit. The human brain is incredibly flexible, and a difficult childhood doesn’t necessarily mean you are doomed for ever.
Second, the youth work lobby has been slow to get onto the neuroscience arguments, and slower to use them in lobbying on young people’s behalf. We need to get out more.