My last post on David Brooks, conservatism and neuroscience inspired a spirited debate. I argued that the discoveries of modern neuroscience seem to support liberal public policies focused on reducing levels of inequality:
While conservatives tend to regard poverty as primarily a cultural issue, solvable by increasing marriage rates and transitioning people to minimum wage jobs, this research suggests that the symptoms of poverty are not simply states of mind; they actually warp the mind. The truth of the matter is that our neurons are designed to reflect their circumstances, not to rise above them. As a result, the monotonous stress of living in a slum literally limits the brain. Our societal inequality leads to very real neural inequalities.
Some people disagreed. They argued that trying to erase inequality is a Sisyphean task, doomed to failure:
To the extent that providing equally favorable environments to children will lift those who are in squalor to a higher level, this will exacerbate the role that genetic differences play in creating inequality: the less a variable varies (i.e., the environment in a social engineering situation), the less it can account for variance in outcomes. Assuming we don't also genetically engineer kids, then genetic variance will remain, and the ratio of genetic to environmental variance will increase.
That's all true. Inequality is writ into the fabric of life. Natural selection, after all, requires random variation among individuals in order to work. That variation leads to genetic inequalities. People are different, and trying to make them all the same is impossible. Nature doesn't subscribe to Communism.
But here's where I part company with the Francis Galtons of the world. I don't think the stubborn presence of inequality means we should stop trying to erase inequality. In fact, I think modern neuroscience has helped us understand what types of inequality we can prevent and what types of inequality are simply beyond our control. Our brains will never all be the same - the IQ test will always have a bell-shaped distribution - but we now know how to provide every brain with the opportunity to reach its full genetic potential.
The good news is that it doesn't take much. For example, the lab of Elizabeth Gould placed marmosets into three different types of environments. The first environment was bare bones. The primates were socially isolated, and provided with a limited assortment of toys. (This, tragically, is "the standard laboratory cage".) The second group of marmosets was placed in a simple enriched environment. They could occasionally play with other marmosets, swing on some branches, and exercise their curious instincts. The third group of marmosets was placed in the extra-enriched environment. They could forage for food, play all day with an assortment of toys, etc.
After four weeks, the scientists looked to see what had happened to the brains of these three different groups of primates. Did their environment alter their neurons? Absolutely. Monkeys living in the bare bones environment had reduced levels of synaptic protein, fewer dendritic connections, and less complexity in their dendritic trees. Whatever genetic differences there were between the individual marmosets were completely overwhelmed by the limiting effects of their impoverished environment.
But what about the monkeys in either of enriched environments? Was it better to be in the ultra-enriched environment (upper-class) as opposed to the moderately enriched environment (middle-class)?
No differences were detected between the brains of marmosets living in the two differentially complex environments. Our results show that the structure of the adult primate brain remains highly sensitive even to modest levels of experiential complexity. For adult primates, living in standard laboratory housing may induce reversible dendritic spine and synapse decreases in brain regions important for cognition.
This is just one experiment, of course, and no child grows up in a standard laboratory cage. But it does illuminate the ways in which very limited environments, especially when those environments are stressful, strongly constrain the brain. Our genes don't even have a chance; we are prevented from reaching our full genetic potential. This same phenomenon seems to also be occurring in America:
"The heritability of IQ at the low end of the wealth spectrum was just 0.10 on a scale of zero to one, but it was 0.72 for families of high socioeconomic status. [...] The genetic contribution to intelligence therefore differs in different environments [...] the same could be said of certain physical attributes such as height, which is heritable when nutrition is not limiting."
Of course, the mind also needs nutrition. I believe that the richest society in the history of the world should able to ensure that all of its children are provided with the minimal set of enrichments necessary for the developing brain.
Comments
There is historical evidence to support your thinking.
Ages ago, it was well known that the key to controlling a defeated nation was to put the rich people into exile, where they would be powerless to cause trouble.
The exiled rich would of course vow to rise to the top almost overnight, but they would always be wrong, for they would never be heard from again, neither by the land they were exiled from, nor the land they were exiled to.
The poor would remain in misery, and the newly poor quickly succumb to it.
Posted by: Roy | February 23, 2007 12:02 PM
I'm glad you're mooting debate here, but you're unclear on the history / positions of various individuals. As for Francis Galton, he coined the phrase "nature and nurture," so he clearly thought that the environment contributed to individual differences in intelligence, the corrollary being that deprived people could improve their intelligence were they brought up in a more hospitable environment. I and every other person who recognizes the reality of IQ believes the same thing.
The difference is that those who have downplayed IQ have a miserable track-record in improving it, not surprisingly. Head Start, for example, has zero effect on adult IQ, despite evanescent gains around the time of the intervention. As another example, the NYT reported on the successful efforts to boost IQ in the third world by vitamin fortification almost 3 years after Steve Sailer did.
http://isteve.blogspot.com/2006/12/32-months-late-new-york-times-catches.html
At the eugenicist extreme, they were certainly correct scientifically that only allowing smarties to have kids would boost the population's IQ, given how heritable it is. That doesn't allow it on ethical grounds, and I know of no IQ researchers who support sterilization, etc. The point is, empirically they were correct, and the John Watsons were dead wrong. Most IQ researches, or lay people who follow the research, are certainly interested in boosting it!
But again, the average American doesn't live like a tortured marmoset in someone's cruel laboratory. In the third world, yes, but not here. I found it strange that someone quoted the heritability of IQ as just 0.1 at the low SES range, as it's typically much higher than that. Here's what the abstract of the cited article says:
"Genetic influences on brain morphology and IQ are well studied. A variety of sophisticated brain-mapping approaches relating genetic influences on brain structure and intelligence establishes a regional distribution for this relationship that is consistent with behavioral studies. We highlight those studies that illustrate the complex cortical patterns associated with measures of cognitive ability. A measure of cognitive ability, known as g, has been shown highly heritable across many studies. We argue that these genetic links are partly mediated by brain structure that is likewise under strong genetic control. Other factors, such as the environment, obviously play a role, but the predominant determinant appears to be genetic."
I'll download the article and see what they were talking about...
Posted by: Agnostic | February 23, 2007 12:50 PM
"I believe that the richest society in the history of the world should able to ensure that all of its children are provided with the minimal set of enrichments necessary for the developing brain."
Exactly right, just because inequalities are inevitable doesn't mean that the range of those inequalities has to extend into circumstances where a contented life is impossible. Fixing the amount of suffering that I see through volunteering with a charity does not require equality. Equality is so unimaginably far away from where we are now apart from some civil rights. It amazes me that some people argue as if there is nothing between socially engineered equality, even genetically engineered equality, and social Darwinism. Sure there is: universal health care, some help for those who fall into the huge gap between being able to hold a job and meeting a government definition of disability, and some minimal shelter for everyone would be a start, something far short of altering our biological evolution, I would think.
Posted by: DavidD | February 23, 2007 6:32 PM
These lines of investigation highlight the consequences of environmental influences on early development:
1) Developmental programming: a growing body of research characterizing and explaining the long-lasting effects of various stressors during early development. (See: Barker hypothesis, fetal programming, epigenetic programming, developmental plasticity.)
David A Leon. 2001. Getting to grips with fetal programming — aspects of a rapidly evolving agenda. International Journal of Epidemiology. 30:96-98
http://ije.oxfordjournals.org/cgi/content/full/30/1/96
2) Multigenerational effects of deprivation: the transmission, due to a variety of non-genetic mechanisms, of the impact of early growth restriction to children and grandchildren. These multigenerational effects make prenatal intervention even more crucial.
Drake, AJ and BR Walker. 2004. The intergenerational effects of fetal programming. Journal of Endocrinology. 180:1-16.
http://tinyurl.com/ywefll
3) IQ as an indicator of developmental stability rather than genes for intelligence. Higher developmental instability - due to environmental stress and/or differential buffering from that stress (as indicated by indicators like fluctuating asymmetry) - is associated with lower IQ. Hence heritability in traits like IQ and brain structure may be more indicative of genes that promote developmental stability rather than genes specifically involved in intelligence.
Timothy C. Bates. 2007. Fluctuating asymmetry and intelligence. Intelligence. 35(1):41-46
http://tinyurl.com/26ykml
We ought to ensure the best possible prenatal care for all American children.
Posted by: Colugo | February 23, 2007 8:24 PM
I believe that the richest society in the history of the world should able to ensure that all of its children are provided with the minimal set of enrichments necessary for the developing brain.
Let me say non-confrontationally that that is terrible logic. It supposes the issue can be decided with money. It can't. Secondly, all healthy children are provided with enrichments enough for the development of their brains. I don't see a lot of adults walking around with partially developed brains. They grow up to have normal brains and normal IQs. Genetics lays down the scaffolding and environment fills in the rest. If there is no scaffolding to begin with there is nothing to develop. If part of the scaffolding isn't filled in then that part gets taken over by other parts of the scaffolding and it gets filled in. If you're born deaf and that part of the scaffolding doesn't get filled in, other parts of the scaffolding encroaches on the hearing part. After around 3 years old the basic structure of the brain has been created. What's left over of the cells used for structuring begin to die off. The rest of the child's brain development is in terms of further refining the structure that already exists.
Furthermore 'inequality' is a red herring. Inequality is the sign of underlying problems not the cause of those problems. It hides problems such as unstable homes, lack of good education and a lack of good jobs. Tackle these issues and inequality will take care of itself. There are black schools in the urban core which are turning out kids going on to college that is way out of proportion to their enrollment size. Each such kid who continues with their education and gets a good job represents a little adjustment to inequality. Provide people with adequate tools and they will fix their own lives.
Sincerely, Rich
Posted by: Rich | February 24, 2007 7:04 PM
"I don't see a lot of adults walking around with partially developed brains."
But Rich, how hard have you looked? How many dendrites have you examined? I had occasion in the past to compare the children's ward at the now-closed St. Louis City Hospital with the middle-class St. Louis Children's Hospital. One difference is obvious. Even the fairly well kids at the poor hospital did very little but sit. The middle class kids were running around playing so much, they would get obnoxious. If these kids are anything like rodents the difference is not some cultural thing. It's in the development of their brains.
The quote you use does not say that the richest society in history will solve the problem by just throwing money at it. That money can go to help all the problems you mention.
Why do you jump to the conclusion that it is something different from what you're saying and therefore "terrible logic"?
Posted by: DavidD | February 26, 2007 5:30 PM
But Rich, how hard have you looked? How many dendrites have you examined?
That's the first thing I ask people when I meet them. "How many dendrites," or more to the point "How many dendretic spines do you have?" Seriously, my comment was in terms of healthy children, enrichment, and the developed brain. I'm quite aware that some children are born with partial brains. My wife's granddaughter was one of them. I'm told she was a beautiful child while she was alive. I'm also aware that there are people living with partial brains. However, so far as I know, these are wholly developed brain is so far as they can be developed. But this was not the frame of reference in which I wrote my comment.
The quote you use does not say that the richest society in history will solve the problem by just throwing money at it. That money can go to help all the problems you mention.
The juxtaposition of "richest society" and "ensure" implies that the problem is one of wealth. It could have read "one of the most advanced societies." In this case the implication is that our advanced state could ensure. But is wasn't written that way. The second premise I challenged is that the state could or should ensure the minimal (whatever that means) sets of enrichments necessary for the developing brain. The normal brain will receive the enrichment needed for normal development. That's the way it is designed. Inequality has little to do with it. Ghetto children, with their ghetto developed brains, if given the proper education, can go on to university and get jobs just as those children growing up out side the ghetto. The lack of state sponsored enrichment has little relevance to the growing brain. Therefore I concluded there was something wrong with the logic of the proposition.
Why do you jump to the conclusion that it is something different from what you're saying and therefore "terrible logic"?
As I pointed out with the education of inner-city children, it is not the inequality that is the problem. The problem is stable families, PROPER education, and availability of jobs. Money is not going to solve these issues. The school district with one of the poorest records for teaching children is also the school district which receives the highest amount of money per child: Washington DC.
I think we need to look beyond inequality. If you deal with the reasons for inequality, inequality itself will be taken care of.
Posted by: Rich | February 26, 2007 6:42 PM