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Category Archives: Developmental Psychology

Abuse and changes in adolescents’ and children’s brains

Two studies reported recently on changes in the brains of adolescents and children who have suffered abuse. Despite my prejudice against ‘we’ve found some kind of brain activity, so that explains everything’ research, this does look interesting, and maybe meaningful.
First ‘past abuse leads to loss of gray matter in the brains of adolescents’, reported in both Medical News Today: http://www.medicalnewstoday.com/releases/238674.php and PsyPost: http://www.psypost.org/2011/12/child-abuse-changes-the-brain-8300 (you probably don’t need both links: they say very much the same things, being lifted from the same Yale University press release). The study was on ‘forty-two adolescents without psychiatric diagnoses’. Hilary Blumberg, one of the authors, has published quite a bit on brain changes in people with bipolar disorder (and so is looking for Szasz’ ‘bad brains’: for all the criticism there is of strictly medical models of mental illness, it’s quite possible that some problems do have physical origins or physical accompaniments).

The brain areas impacted by maltreatment may differ between boys and girls, may depend on whether the youths had been exposed to abuse or neglect, and may be linked to whether the neglect was physical or emotional.
[…]The reduction of gray matter was seen in prefrontal areas, no matter whether the adolescent had been physically abused or emotionally neglected. However, in other areas of the brain the reductions depended upon the type of maltreatment the youth had experienced. For example, emotional neglect was associated with decreases in areas that regulate emotions.
The researchers also found gender differences in patterns of gray matter decreases. In boys, the reduction tended to be concentrated in areas of the brain associated with impulse control or substance abuse. In girls, the reduction seemed to be in areas of the brain linked to depression.

The original paper is Erin E. Edmiston; Fei Wang; Carolyn M. Mazure; Joanne Guiney; Rajita Sinha; Linda C. Mayes; Hilary P. Blumberg (2011) Corticostriatal-Limbic Gray Matter Morphology in Adolescents With Self-reported Exposure to Childhood Maltreatment Arch Pediatr Adolesc Med.;165(12):1069-1077.
The abstract is here: http://archpedi.ama-assn.org/cgi/content/abstract/165/12/1069

Blumberg points out that adolescents’ brains are still pretty malleable, so these changes may not have long-term significance

Here’s another related finding (http://www.psypost.org/2011/12/child-abuse-changes-the-brain-8300):

When children have been exposed to family violence, their brains become increasingly “tuned” for processing possible sources of threat, a new study reports. The findings, reported in the December 6th issue of Current Biology, a Cell Press publication, reveal the same pattern of brain activity in these children as seen previously in soldiers exposed to combat.
The study is the first to apply functional brain imaging to explore the impact of physical abuse or domestic violence on the emotional development of children, according to the researchers.
“Enhanced reactivity to a biologically salient threat cue such as anger may represent an adaptive response for these children in the short-term, helping keep them out of danger,” said Eamon McCrory of University College London. “However, it may also constitute an underlying neurobiological risk factor increasing their vulnerability to later mental health problems, and particularly anxiety.

The stimuli used were pictures of angry, neutral and sad women’s faces. The heightened response was shown to angry faces, but not sad faces. The children had been ‘exposed to documented violence in home’ and were matched with controls. In the .pdf version, I can’t see any information about the age of the children, but there were 20 in the experimental sample.
The reference is McCrory, De Brito, Sebastian, Mechelli, Bird,  Kelly and Viding (2011) Heightened neural reactivity to threat in child victims of family violence Current Biology, 21 (23), R947-R948, and the full article is at http://download.cell.com/current-biology/pdf/PIIS0960982211011390.pdf.

Again, this looks as though it might be saying something useful, though the ‘long-term’ claims would maybe depend on plasticity again.

Both news releases on PsyPost have the same old useless ‘brain’ picture on them.

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BPA and kids’ brains: Small scale psych controversy supports NTU lecturer’s points brilliantly

Here’s an example of the kind of thing Christina was talking about in Tuesday’s lecture – only worse, really.
http://psychcentral.com/blog/archives/2011/10/25/bpa-and-childhood-problems-another-crappy-finding-from-pediatrics/
The link here is to a post by John Grohol on the PsychCentral blog (http://psychcentral.com/blog/).
It’s about a paper in Pediatrics (a peer-reviewed journal) about a study on whether pre-natal exposure to a possibly damaging chemical, BPA (used in plastics production, I think), affects hyperactivity and aggression in 2-year-olds. The headline  for the paper on PsychCentral (probably based on a press release from the journal or university) says it does:
BPA Prenatal Exposure Linked to Behavioral Problems in Kids
– then the first paragraph says it doesn’t, really:

New research suggests fetal exposure to a chemical used to make plastic containers and other consumer goods called BPA is associated with a slight but nonsignificant increase in behavioral and emotional problems in young girls.

‘slight, but non-significant’ means that we can’t be confident that the difference didn’t arise by chance, and as scientists, we shouldn’t find that evidence convincing (or conversely, we should be fairly confident that the null hypothesis has been supported). So this is really, an example of the kind of negative result Christina was talking about.
So, how to deal with it? It could be stuffed away in the bottom drawer, though it would be worth publishing as a negative finding:
“We know that BDA has been shown to have neurotoxic effects elsewhere, but it doesn’t look as though moderate levels of prenatal exposure  has much effect on hyperactivity and aggression in toddlers, so that’s one thing less to worry about.”
– no! Much better to publish it as a positive finding, even though it isn’t: ‘Deadly chemical poisons our kids’ brains!’
That gets round Christina’s negative result problem nicely*.
If you look at the detail Grohol gives further down the blog, it actually gets a bit worse. Grohol points out that the accepted level of difference for significance (established in the norming of the original scales) on the scores for the scales the researchers used is 10 points, and only two of the published 40 differences (for different age groups, boys and girls, etc) reach or exceed that level. Grohol comments:

Here’s a study that looked at a total of 44 variables (when you count the analysis of gestational BPA versus childhood BPA levels) and found significance in only 2 of them.
To me, that’s an interesting correlation.

Hang on: if we’re talking about significant at the 0.05 level, that means we would expect a result like this to arise by chance in one out of 25 trials. So, we find two results significant at this level in 44 trials? Isn’t that really very close to what we’d expect to find by chance? Don’t we teach you that if you do lots and lots of comparisons, you have to allow for the odd apparently significant result which WILL pop up, just by chance? Anyone who thinks it’s positive evidence is a statistical ignoramus. Here’s a recipe for scientific success, kids – do lots and lots of comparisons: some of them are bound to be significant – and statistical significance is the only thing that counts, right? (Actually, wrong – but maybe that’s another blog post.)
Grohol comments:

It seems like a month doesn’t go by when this journal is publishing more crappy science, and then draping it in a public relations campaign that gets everyone’s attention. (Actually, to be fair, the science is sometimes fine; it’s the over-reaching conclusions drawn by the researchers and the PR media machine that is truly vomit-inducing.)

I think that’s a good summary (though ‘vomit-inducing’ is both a bit strong and wimpy: this stuff doesn’t make me want to throw up: it makes me want to put my fist through the computer screen). Always suspend judgement on the headline, until you’ve read down to the the 27th paragraph – the truth is often down there in the details. Better still, look at the original paper, if you can. In this case, it’s at
http://pediatrics.aappublications.org/content/early/2011/10/20/peds.2011-1335.full.pdf+html
Braun, Kalkbrenner, Calafat, Yolton, Ye, Dietrich & Lanphear (2011) Impact of Early-Life Bisphenol A Exposure on Behavior and Executive Function in Children †

*Actually, my analysis above is over-simplified. The results do look non-significant and unconvincing, but they are (mostly) in a negative direction. So we might say  ‘it looks a bit as though there might be a negative effect but we can’t be (scientifically) sure about that’. But hang on: these are our children’s lives we’re talking about! Do you mean that there’s even a slight risk that exposure to BPA would lead my child to grow up to be a London rioter or to be like Paris Hilton? Shouldn’t we think about banning it right away, just to be safe? (review Christina’s points about large and small effects here). Maybe this study is at least a basis for further research after all.
…but it’s also politically complicated. Let’s say someone, somewhere, tried to make a court case about BDA and psychological damage. This might be energetically opposed by companies who find using BDA in their products convenient or profitable, or who might be liable for damages (it’s happened with asbestos and tobacco like this). so the plastics company calls an expert witness:

Counsel: One of the pieces of evidence the opposition has produced is the paper by Braun & al, which shows that two results out of 44 apparently showed a significant negative effect of my client’s product. Dr Miller, how would you comment on such an interpretation?
Miller: Errr, it’s not very convincing
Counsel: Didn’t you write, in 2011, that anyone who thought that such a result was convincing was a ‘statistical ignoramus’?
Miller: OK, yes
Counsel: So we’re dealing here with a case based on statistical ignoramicity?
Miller: You could say that, yes

So dodgy results like this are both (strictly) scientifically worthless, potentially significant (in the non-statistical sense) pointers, fodder for misleading scare stories, and hostages to fortune if used to support a case in the real world – all at the same time. This stuff is complicated (one of the messages of Schools of Thought, after all).

If you look at the original paper, the conclusion is:

The results of this study suggest that gestational BPA exposure might be associated with anxious, depressive, and hyperactive behaviors related to impaired behavioral regulation at 3 years of age. This pattern was more pronounced for girls, which suggests that they might be more vulnerable to gestational BPA exposure than boys. In contrast, childhood BPA exposure did not exhibit associations with behavior and executive function at 3 years of age. There is considerable debate regarding the toxicity of low-level BPA exposure, and the findings presented here warrant additional research.

…which is pretty much what I was suggesting (note the use of words like ‘suggest’ and ‘might’), so maybe we (and Grohol) shouldn’t be too hard on the authors.

How much do babies remember?

http://www.psypost.org/2011/09/what-do-infants-remember-when-they-forget-7280

A PsyPost report of research by Melissa Kibbe, of Johns Hopkins University, and Alan Leslie, (Rutgers) on what six-month-old babies remember about an object which is no longer visible (about their concept of ‘object permanence’). Seems they remember that something was there, but may not remember specific details (was it a triangle or a circle?) – which might be interesting to cognitive modellers in that there might be something systems as well as triangle-or-circle systems – but it’s also interesting as an example of the simple but ingenious methods which this kind of research has developed since Piaget’s day (remember, kids, Piaget was right in some general principles, but wrong on a lot of the details)

…and it shows, again, how cognitively competent young children are.
An example with a slightly older child. When my oldest child was about 18 months old, we drove all round the USA in a Morris Marina (don’t ask) – which had (fairly weedy) air conditioning, at a time (1980) when A/C was pretty well unknown in the UK. My son had a vocabulary of a few words at the time, mainly words for animals or food. More than a year later, back in the UK, he was out in a car with his grandparents on a hot day, and the heat in the care was uncomfortable. “What we need,” he said, “is a hole there (pointing to the dashboard) and cold air comes out of it”. We’d never discussed A/C with him, or reminded him about it. Now, as grown ups, people typically remember nothing before about three years old, but here’s a 2+ child remembering pretty accurately things that happened a whole year ago, which he didn’t have words for at the time – ‘cold’, ‘air’, ‘comes out’ – and so which must have been stored in some pre-linguistic way. I’m not claiming this is unusual: lots of people can give anecdotes like this, but it’s a problem for the textbook accounts of the limited memories of young children, and a challenge to researchers to find methods which are sensitive enough to research this kind of thing in young children, just as they’ve used the concepts of surprise and attention in babies (as in the research above) so brilliantly to help us understand babies’ cognitive world, going back to Tom Bower’s work in the 1970s:  http://books.google.co.uk/books?hl=en&lr=&id=xVUK3gIy-2QC&oi=fnd&pg=PA85&dq=tom+bower+perceptual+world+child&ots=iXKSe6GR79&sig=A53HGposj0OjjRCK42AXUOFRexk#v=onepage&q=tom%20bower%20perceptual%20world%20child&f=false

Is bilingualism good for your brain?

An article by Erica Westly in July/Aug 2011 Scientific American Mindhttp://www.scientificamerican.com/article.cfm?id=the-bilingual-advantage ) suggests recent research shows that children who speak two languages are more flexible and creative in (admittedly lab-based) tasks than monolingual children, and don’t show any intellectual or linguistic delay (Kovács & Mehler, Adi-Japha & al). A sidebar by Lauren Migliore also points out that bilingualism seems to protect against cognitive decline in old age (research by Bialystok at York U, Canada).
Not surprising really, except that I remember lots of research about the cognitively damaging effects of being bilingual – but maybe that was done  in a culture that saw poor ‘immigrants’ (the most obviously bilingual group) as being inferior. There was another multilingual group – of classicists, diplomats, royalty (I guess Prince Philip speaks English, Danish and Greek, at least), and other members of the social elite – but they were ‘gifted polyglots’.
The article points out that the idea of bilingualism being intellectually damaging wasn’t visible in the US in the 19th century, when it was very common in a nation built on immigration, but it’s a more acceptable idea in monoglot countries like 20th century USA and the UK. Maybe we’re becoming a bit more open in our thinking now – or maybe more psychological research is being done by people who aren’t from monoglot anglo/US backgrounds (note the names of the researchers mentioned above).
Note for Schools of Thought students: another politics/psychology/society interaction? Remember that it was in the first part of the 20th century that psychology was mobilised to ‘scientifically’ declare immigrants to the US intellectually inferior in other ways.
This new research fits my prejudices – I always suspected  that people (even if poor and foreign) who could speak several languages were smarter than me, who has a bit of French, less Latin, and hardly any Finnish*. Maybe it also helps to explain all those brilliant musicians from West Africa, where it seems pretty usual to speak several languages.
Could also be bad news for lazy Anglophone academics like me, who rely on  the fact that Academic English (not the same as UK English, but close) has become the new Latin of the academic world (but maybe not for long).
Another thought: how much does the difference in languages matter? Compared with other world languages, Northern European languages are more-or-less dialects of the same basic form – apart from Finnish, which comes from a different root entirely. Does being bilingual in Finnish and French give more intellectual advantages than being bilingual in English & French? And Sorhai, Tamasheck, Peul, Dogon, French, English and probably a few more (as were spoken by Ali Farka Touré) could be better still.

*En puhu Suomea, anteeksi. No, olen Englantilainen

Transfer of Learning in Infants but really: Inventive Developmental Psychologists

http://researchnews.osu.edu/archive/learntransfer.htm
Press release from Ohio State university, about the work of Julie Hupp (pictured below):
INFANTS LEARN TO TRANSFER KNOWLEDGE BY 16 MONTHS, STUDY FINDS
Interesting in itself, but also a great example of how ingenious developmental psychologists  find effective ways of working out ‘what babies think’.

Julie Hupp, Ohio State U

“Singing to children may help development of language skills”

http://www.guardian.co.uk/lifeandstyle/2011/may/08/singing-children-development-language-skills?INTCMP=SRCH

“Parents should sing to their children every day to avoid language problems developing in later life, according to a consultant. Too much emphasis in the early years is placed on reading, writing and numeracy, and not enough on the benefits of singing, according to Sally Goddard Blythe, a consultant in neuro-developmental education and director of the Institute for Neuro-Physiological Psychology.
Singing traditional lullabies and nursery rhymes to babies and infants before they learn to speak, is an essential precursor to later educational success and emotional wellbeing”, argues Blythe in a book.  Song is a special type of speech. Lullabies, songs and rhymes of every culture carry the ‘signature’ melodies and inflections of a mother tongue, preparing a child’s ear, voice and brain for language.”

I always knew it was a good thing to sing to my children (they didn’t always agree) – but perhaps I shouldn’t sing Eastern European or African songs, if Blythe is right.
Of course, some of this has been known for a long time. Peter, Paul & Mary claimed back in the 60s that every children’s song should have three characteristics: simplicity, so the child could understand the song; repetition, to lull the child into a false sense of security; and pathos, to prepare the child for future traumatic experiences. Nice to hear a neuro-developmental education consultant (sort-of) confirm it – but is there actually any evidence for these claims?
if you read the rest of the article, you’ll find that the book is The Genius of Natural Childhood, to be published by Hawthorn Press  – and that’s the real point of this article. It’s a public relations promotion for an upcoming book, with an interesting hook to get journalists to think it’s worth writing about. On my ‘psychology & media’ third year option, we’ve tracked lots of ‘psychology’ stories like this. Lots of what you hear about psychology in the papers/TV comes from smart PR releases, some of which are just entertaining made-up stuff, and some of which are honest reports of carefully-carried-out research. You have to make up your mind which to believe. Often the killer question is ‘what’s the evidence’?
You might remember that one of the sources of the general knowledge psychology myths mentioned when I discussed this in the Schools of Thought lecture was ‘the media’. This is one of the ways those myths arise/get repeated.

In sprite of all that, I’ll still remind my children how useful it was that I sang to them when they were little (they won’t put up with it now).

Direct instruction or find out for yourself?

From Medical News Today:

“It turns out that there is a “double-edged sword” to pedagogy: Explicit instruction makes children less likely to engage in spontaneous exploration and discovery. A study by MIT researchers and colleagues compared the behavior of children given a novel toy under four different conditions, finding that children expressly taught one of its functions played with the toy for less time and discovered fewer things to do with it than children in the other three scenarios.”

The MNT article http://www.medicalnewstoday.com/releases/230117.php gives a summary of the research (presenting children with novel, multi-function toys and seeing how many functions they find/use).
The full paper is available at: http://141.14.165.6/CogSci09/papers/340/paper340.pdf
Perhaps we shouldn’t tell our students so much stuff….