Growing Pains in the Brain

Stuart WG Derbyshire

Allen and Smith argue that there is a “sheer predictability of children’s early years for their future outcomes… if a child is born into a home where they are nurtured, where conversation takes place, where someone reads to them then, quite simply, their brain develops properly… it is in that delicate and vulnerable period [0-3 years] that our lives can be made or not.”

http://developingchild.harvard.edu/initiatives/council/

The report argues that there have been exciting new developments in neuroscience that we must capitalise on “to build a strong foundation for improved learning and behavior that will produce better outcomes in academic achievement, economic productivity, responsible citizenship, and succesful parenting of the next generation.”

What is the Evidence?

Newborn infants have more neurons than they will ever use

Those neurons generate high synaptic density in the first 3 years

Synapses are then pruned and unused neurons die

Critical periods Synaptic pruning is more severe in an

impoverished environment

We Are Born With More Neurons Than Are ‘Needed’

Between 40 and 75 percent of all neurons born in embryonic and fetal development do not survive

They fail to make optimal synapses

Time-lapse imaging of synapse elimination

Unused Neuronal Cell Bodies Die

Critical Periods

Just 3-days of monocular deprivation just before 1-month of age causes a profound shift of cortical innervation to favour the non-deprived eye

Deprivation Causes Brain Structure Changes

Deprivation

A healthy 3-year old with an average (50th percentile) head size compared with an extremely neglected 3-year old (3rd percentile)

Functional ImplicationsInfants (mean age 9 yrs) placed into a Romanian orphanage by 6 weeks of age for a mean duration of 38 months before adoption compared with a control group of non-institutionalised infantsThere is reduced glucose

metabolism in and around the hippocampus

Chugani et al (2001) NeuroImage 14: 1290-1301

Gesture and Language

It’s Not Relevant

We cannot extrapolate from the severe to the normal range

We shouldn’t ‘biologise’ socioeconomic problems

The Science is Theoretically Shallow

The model (brain + environment = experience) is wrong

What we are extends beyond ourselves, our immediate environment and our individual past because we are social creatures connected through language, tools and a shared history

The Brain Is So Over Rated

What we ‘naturally’ are is transformed in a myriad of ways and connected to a deep history

Nurse Ryan’s embarrassment illustrates this point

History Divides Psychology

George Herbert Mead– Studied under Wundt in Germany– ‘Mentality’ is the relationship between the organism and

stimuli and is functional rather than substantive Lev Semyonovich Vygotsky

– Lived through the Russian Revolution– Viewed consciousness as the organising feature of

mind following his assault on Russian psychology’s focus on reflex and reaction

Pavlov, Watson and Skinner– The founders of modern behaviourism and the

gravediggers of Mead, Vygotsky and their followers

Derbyshire SWG & Raja A (2008). What makes humans special?http://www.spiked-online.com/index.php?/site/reviewofbooks_article/4704/

I’m a Mind, Get Me Out of Here“…we suppose that by conducting ever more penetrating brain scans… we shall understand how thought becomes possible. These expectations are not going to be fulfilled… We shall never be able to capture what happens between people in a brain scan. To be sure, we may see patches of colour that betray all kinds of neurological goings-on when individuals relate to

one another. These events in the nervous system are a necessary part of the story. Yet they amount to only one small piece of a much broader picture. It is a picture that involves another person, and each person’s experience of the other. The roots of thought are embedded here.”

Socially Conscious Thought and experience cannot be

adequately understood as long as their social origins are obscured– You did not, all by yourself, generate

the content or momentum of your conscious life

Peter Hobson describes the development of social consciousness: “One might say that they were responding to the world according to someone else… The discovery is a discovery in action and feeling, rather than a discovery in thought”. And, later, “…her new-found grasp of symbols allows her to locate and anchor aspects of her interpersonal understanding. In a way, she can arrive at true concepts or thoughts about the mind… only when she can use words or other symbols to encompass those thoughts… Symbols, and especially words, help her to sort out and refine what she has gleaned from her engagement with others.”

Conclusion

We are more than just a brain When deprivation is severe then treating

human beings as mechanical objects can make sense

But boiling normal development down to mechanics boils out what makes us human