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[分享]Washington Post: More Evidence for Infant Attachment

Posted: 2007-02-26 7:45
by Jun
Plagued With Relationship Troubles? Blame Your Parents.

By Shankar Vedantam
Monday, February 12, 2007; A02


So, Valentine's Day is two days away, but you know he isn't going to bring you any flowers. And instead of a cuddle and a kiss, you know she is going to dig up that old canard about your mother.

Does your relationship feel like an endless rerun of "Who's Afraid of Virginia Woolf?" -- Edward Albee's grim masterpiece of domestic disharmony? Do you always spend Valentine's Day alone? Do all those smooching couples sound like idiotic moths banging their heads against a windowpane?

If the answer to any of these questions is yes, science can finally provide a simple explanation -- and a measure of grim satisfaction: Blame your parents!

Forget about Hallmark cards and chocolate. Just in time for Valentine's Day, scientists are announcing the results of an astonishing two-decade-long study that explored the connection between insecure infants and relationship problems in young adults. Turns out the kind of baby you were at 12 months can say a lot about the kind of lover you will be at 21.

"If you are more insecure when you are 1, you are more likely to experience more negative emotions in your relationship with your current partner when you are 21," said psychologist Jeffry Simpson at the University of Minnesota.

People from Sigmund Freud on down have made arguments about the role of early relationships in later life. But Simpson and his colleagues have shown for the first time, in a paper in the current issue of the Journal of Personality and Social Psychology, an empirical connection between early behavioral patterns and romantic relationships years down the road.

The study closely tracked 78 people over a quarter-century, starting when they were babies. Mothers and infants were brought into a laboratory, and the mothers were asked to leave briefly. The infants became upset, of course, but the psychologists were interested in what happened when the mothers returned. Some infants clung tightly to their mothers and sought comfort. In a little while, they calmed down. But others refused to calm down even after lengthy soothing. And some babies refused to turn to their mothers for comfort at all.

Simpson said research has shown that secure infants turn to their parents when they are upset: "The kid learns, 'I can count on my parents to calm me down.' They learn to turn to others. Whereas insecure kids learn that my parent is either rejecting or they learn my parent is neglectful. Or 'I have to protest to get attention.' "

The researchers checked in with the children again when they were in first through third grade. They asked teachers how each child compared in social skills with other children in the class -- especially when the child was upset. Did she act out her anger or reach out to others to solve the problem?

The next check came at another developmental milestone, when the kids were teenagers. The psychologists studied how the adolescents reached out to their best friends for support: "Do you rely on your best same-sex friend at 16 to calm you down or do you distract yourself?" Simpson asked.

Finally, the researchers studied the people when they were between ages 21 and 23. They asked the volunteers how often they felt happy or sad in their romantic relationships. The volunteers' romantic partners were asked to describe the relationship as well. Finally, the couples were presented with a conflict and given 30 minutes to try to resolve it. Researchers videotaped the couples as they dealt with the problem and the emotions it produced.

"We find if you are insecure at age 1, that predicts being rated as being less socially competent than your peers during grades one-two-three, which predicts less reliance on your best same-sex friend when you are upset at 16, which then predicts more negative emotion in a romantic relationship at age 21 to 23," Simpson said.

Does this mean all insecure infants are doomed to a lifetime of unhappiness? Simpson argued otherwise. Human destiny is not so circumscribed, he said. What the study showed is how each developmental step influences the next, positively or negatively. While it is certainly best to be started in the right direction, people can always learn the skills needed for successful relationships.

At its core, said Brooke Feeney, a social psychologist at Carnegie Mellon University who published another study in the same journal, research into the factors that predict happiness in our personal lives reveals a paradox about relationships -- and a timely lesson for Valentine's Day.

Contrary to the popular American myth that people left to fend for themselves become strong and independent, the psychological research seems to show exactly the opposite is true: It is the people who are confident enough to reach out to others for help -- and to whom help is given -- who become truly capable of independence.

Like those crying infants in Simpson's study who turned to their mothers for support and, once comforted, resumed their explorations of the world, Feeney found that romantic partners similarly become more independent once their emotional needs are met.

"It is a lot easier for people to take risks and accept challenges when they know someone is available to help them and comfort them if something goes wrong," Feeney said. "The most secure individuals are able to turn to other people for support."
More evidence to support the implication of infant attachment in adult personalities. A securely attached infant has a better chance of becoming a happy and secure adult. I'm not saying adults have no control over their emotional life or it's too late to live happily, but the control one has is more limited than the general notion.

Posted: 2007-02-26 13:58
by 猫咪头
Who the hell IS secure at age of 21?

Did the editor's mom drop him upside down as an infant?

(See, I can forgive the author for writing it, 'cause people think up shit all the time. But the editor is too imcompetent to do his/her job, it appears.)

Posted: 2007-02-26 14:00
by 森林的火焰
Epigenetics, all because of epigenetics. 8)

Posted: 2007-02-26 15:21
by Jun
猫咪头 wrote:Who the hell IS secure at age of 21?
I have met plenty of kids who are secure at 21.

Even among the insecure, there are some more and some less insecure. Comparison, comparison, comparison.

I don't agree with your quick dismissal of the findings. Infant attachment disorder has been observed and replicated in many behavioral studies, including other primate studies.

This is not genetics or epigenetics, but clearly behavioral science. This one squarely falls under nurture in the Nature versus Nurture debate.

Just because one does not like the conclusion or the conclusion is intuitively contrary to one's preconceived notions, doesn't mean the conclusion is wrong. The attachment defect happens to be one of the better researched and better documented area in psychology.

Posted: 2007-02-26 15:40
by 猫咪头
No, honey, the conclusion is intuitively sound.

And that is the problem. The sample size is too small, and both the explanatory variable and the response valiable are subjective.

It is just bad science. We cannot endorse these behaviour, can we?

If we tolerent bad science with "sound all right" conclusions, what do have against pseudo-science in the end? Nothing.

Posted: 2007-02-26 16:02
by Jun
I don't agree that every study has to rigidly adhere to a certain guidelines. The generally accepted "good clinical practice" methodology for proving the safety and efficacy of a particular medical treatment is fine for its own purpose, but epidemiological, observational, cohort studies in the natural setting cannot always strictly adhere to these guidelines.

If one has to have a 3,000 sample size even to begin to conduct a study, certain disciplines would never be able to investigate anything, especially a longitudinal study that hunt the same group of people down for 20 years.

This is not unassailable proof, but within psychology and psychiatry research, this is not bad. Moreover, this is not an isolated study on someone's dreamed-up theory (unlike just about every theory by Freud and his followers), but a confirmatory one. Prior studies, many much smaller but were conducted in controlled laboratory settings, have all supported the infant attachment disorder. HOwever, those studies were short in duration. So having some long-term data to confirm the lasting effects of infant detachment, is adding to the evidence and building our understanding. It shows that the attachment disorder can have a lasting effect.

Psychiatry and psychology are limited by a variety of factors and cannot be conducted or judged purely by biochemical and biomedical standards. We're not testing someone's change in hemoglobin numbers or blood pressure data. And keep in mind that numbers, as assuring as they seem to scientists and the public, can also be very arbitrary (would a blood pressure of 145/90 really kill you?).

It is true that psychiatry and psychology are not nearly as reliable and "pure" as science, since they are still largely observational and qualitative. Nevertheless, there are ways to relatively and gradually approach the truth through incremental steps.

Between the perfectly designed, pure and unassailable studies and worthless garbage, there is a vast grey zone of potential proofs to be discovered and accumulated. It's not an all-or-nothing dichotomy. Frankly, I would rather place a little more confidence in smaller studies with no obvious investment of side-taking than large, sanitized studies paid for by an industry that's trying to make a profit from the results.

Pseudoscience is most often driven by a vested interest to prove one particular answer and hence a heavy dose of predetermined bias.

Posted: 2007-02-26 16:35
by 森林的火焰
There was an mouse behavioral study reported on one issue of Nature.
The mice received less nurture from their mother behaved more hysterical, less secure when grown up compared with their brood brothers. Then they find one specific neuron receptor expressed at a much lower level in these mice. Then they found the gene encoding this receptor was heavily methylated (labeled as "off" in genome) in these mice but those with enough care from their mother showed a normal expression level and had less methylated promoter. If the promoter of this gene was artificially methylated, then the mice behaved just as hysterical and insecure as those received less care.

Posted: 2007-02-26 19:58
by Jun
Thank you for providing this excellent and timely example to illustrate the point so elegantly. See, I'm not making this up.

That's a classic example of the interaction between environmental factors/stimuli and gene expression. For example, when a person is exposed to allergen, the genes that express certain inflammatory chemicals (interleukins, for example, and interferons) are highly activated, and more copies of RNA are made from these genes to produce more proteins.

This is how we live -- how we respond to environment stimuli and react and behave accordingly. However, just the mere fact that the expression of so-and-so genes are heightened by an external stimuli is not a reflection of genetic predisposition or unique genetic mutation/characteristic of a particular organism. On the contrary, before we discover any deviations, it's prudent to assume that ALL mice have this receptor gene that can be turned on and off (through methylation) based on mother's nurturing stimuli. In other words, ALL mice would theoretically react by becoming more or less "hysterical" as a response to the amount of nurture in their infancy.

Granted however, that this is merely a single-gene/single-protein phenomenon. There may be mutations that cause individual variations in this phenotype. Or, there could be other genes that contribute to or modulate the process, making it not as clear cut as switch-on and switch-off.

However, I do not think this process is, strictly speaking, epigenetics. The definition of EPIGENETICS refers to INHERITED characteristics (implying individual variations) very much similar to the way genotypes are passed on from one generation to the next, only these characteristics are not passed on THROUGH DNA. They may be passed on from perhaps the RNA or proteins in the mother's egg/gamete outside the nucleus. There could be other mechanisms that we don't know of.

If this nurture-responsive, switch-on/off receptor gene that you refer to works as you describe (I have to go check out this article. Do you have a link, please?), it is ordinary gene expression and thus not epigenetics.

Posted: 2007-02-26 21:33
by
jun, 这个epigenetics,指的不是小孩从妈妈那儿遗传的,是细胞间的遗传,或者说,这个遗传,指的是chromotin合成时候总保留母代的结构特征。

In defination, epigenetics is the heritable changes in gene regulation that occur without a change in DNA sequence. in reality it refers to DNA methylation, covalent hisotne modifications, and some other changes. these modifications label the chromatin structure as the region on/off for transcription.
the case 森林的火焰 mentioned is a typical epigenetic change regulating gene expression. in fact, I do not know anybody working on transcription regulation not talking about epigenetics these days. it is just part of the ordinary gene expression.

Posted: 2007-02-26 22:25
by Jun
Oh? Do we know whether this particular gene regulation is a heritable (between cell generations) change or just an ordinary cellular signaling pathway that regulates the genetic expression?

I did a very rough search and couldn't find the source article.

Posted: 2007-02-27 2:05
by
Jun, I am not sure what you mean by "ordinary cellular signaling pathway ".
signal transduction pathway is a series of events that transfer the signals from outside the cell to inside. they can be upstream events of transcription regulation and direct it eventually, but they are not part of it. when people working on transcription regulation, in most cases, they look at much localized changes, eg, what is the chromatin context like, how can proteins be recruited to the gene, which part of the regulatory element is important for what...

epigenetic changes, on the other hand, are a layer of transcription regulation. are they heritable? DNA methylation sure does, but the histone modifications may depends. it is sure the general histone modification levels along a gene or at a gene locus are heritable. the euchromatin is labeled by high acetylation, and the heterochromatin is labled by methylation. but it is hard to give a simple yes/no answer when talking about particular histone modification at a site of an inducible gene. most of the histone modifications are reversible, and on an inducible gene they are changing in response to hundreds of things. it simply does not make sense to look at the heritability unless the turning between euchromatin and heterochromatin or other relatively long-term chromatin changes are involved.

I have not seen the paper 森林的火焰mentioned. I have no idea wjether the gene they talk about is inducible or not. if the methylation in that paper is on DNA but not histones, then it sounds to me like the gene is within an euchromatin region in the normal mice, but the region turned to be hetero in those receiving less nurture.
this is just a guess.

Posted: 2007-02-27 8:02
by 森林的火焰
Even I failed to find back that minireview talking about the paper from nature. :oops: But waht I remembered is more like that unnurtured CpG island is heavily methylated, while nurtured is not. Saw a gene called PEG3, but didn't look through the abstract yet.

Posted: 2007-02-27 8:57
by Jun
What I'm confused about is this: I assume this expression regulation occurs in neurons (as one would expect for the hysterical traits, but who knows?), right? But isn't it true that neurons do not undergo mitosis? (at least, mammalian neurons?) :headscratch: So, if we are just talking about one generation of neuron cells. Sounds like it could be just a simple regulation? Is there histone modification in this case? I don't know.

Anyway, this is stretching way beyond the realm of my amateur biology. :dizzy:

Posted: 2007-02-27 12:09
by
oh, dear, never mind. this is the only area I am confident to say I know something about.

mitosis and transcription are two different things. DNA replication (division) transfers the genetic imformation from DNA to the newly synthesised DNA, while transcription transfers it to RNA. It does not matter whether the cell goes division or not, the transcription and expression always happen. If the gene is inducible, then in response to the correct signal, the whole mechinery got recruited to the gene. the machinery includes lots of proteins working together (activators and co-activators) and the chromatin structure as the obstacle for the recruitment of these activators at the first place and undergoing structural change upon stimulation. even it is constantly expressed (so called constitutively expressed genes), the level of expression is still controled by transcription regulatory machinery. it is just always there and do not response to signals.

Yes, "heritable" is in the definition, but every word in the molecular biologist's dictionary may have a different meaning.
eg, in the world of molecular biology, "in vivo"never means something done "in a living animal". rather, it means "in a cell". A piece of DNA goes replication in a totally in vitro biochemistry assay, the newly generated DNA is still called the offspring, and the chromatin structure may be "inherited" from the template.

btw, they put heritable in the definition because the whole epigenetics idea was coming from the fact: turning on/off the 20-30 thousand genes is not enough for all the phenotypes we have, so there must be something on top of the DNA sequence that is also heritable and controls the expression.

in fact, when we look at the histone modifications, we do not really think about the definition. It is heritable, does not mean it has to be inherited at this site this particular time.
there are some people looking at the heritidy……I may stop here and get some sleep.

森林的火焰,某白,给点技术支持谢谢。

Posted: 2007-02-27 19:19
by Jun
给咱多讲讲epigenetics和普通signal transduction的区别吧。不涉及到细胞分裂("细胞传代")的核外的基因表达控制方面的特征也算epigenetics里面的一部分吗?我一直以为要有传代才算呢。

Posted: 2007-02-27 21:05
by orangetabby
That's pretty cool stuff 橙 and 火焰 talked about. Very interesting.

And the take home message I got was: you blame your relationship problem on your parents, to be more speicific, on your mom, LOL.

Posted: 2007-02-27 22:07
by 森林的火焰
Epigenetics和transcription control是两个层次的调节。Epigenetics是细胞可以接受外界信号(从别的细胞传来),改变自己某些基因的打开或关上的状态。这个过程不涉及复制。Epigenetics的信息,在细胞分裂的时候可以原样拷贝分到两个子细胞里去,epigenetics和genetics的不同,在于epigenetics可以是外界环境影响基因组,并在有需要的时候遗传下去。
遗传上还比较有趣的一件事(虽然跟这个题目关系不大)是genome imprinting。某些基因,只有来自父系的那个,或母系的那个才得到表达,另一方的被关掉了。所以经常听见有人抱怨孩子不象自己,象另一半,可能是自己贡献的管那个性状的一组基因在孩子里没有发言权。。。

Posted: 2007-02-27 22:54
by hh
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Posted: 2007-02-28 0:19
by
这俩东西,不容易混啊?Jun你咋能不明白这个呢?
signal transduction是把细胞外的信号传递到细胞内,发生的地方是从细胞外到细胞质到核内,都算上。转录是在细胞核里进行的。signal transduction跟转炉有关的就那么一点点,就是他把某些transcription factor释放或者刺激或者怎么着一下,让他们能进到细胞核里。这样他们就能参与转录调控了。

signal transduction是说那些蛋白质怎么去到他们该去的地方,transcription regulation是说这些蛋白在那地方怎么工作。
打比方说,signal transduction是说我怎么上班,走路还是开车,走哪条路,被哪个红绿灯拦上了;transcription regulation是说我进了办公室做什么实验写什么文章。

epigenetics 怎么热起来的呢?其实组蛋白修饰这个现象,80年代初开始就在完全体外的生化试验里证明了。简单的说就是他们在体外合成了一段chromatin,包括DNA和组蛋白(histone)(组蛋白还有一大堆结构,就从简了),他们发现,当DNA包装成chromatin(就是DNA绳子缠着histone石头的结构)的时候,transcription factor就不能结合到DNA上。可是没有这个包装,只有dna绳子的时候,就可以结合。而如果histone加上了一下共价修饰的话,石头缠绳子就缠不紧了,那么transcription factor就又可以结合了。

这个结合,是transcription factor发生作用的第一步。一般来说不结合就转录不了。

可是如果你查文献的话,会发现90%的文章都是在00年以后发表的。为啥到新世纪了epigenetics就焕发光彩了呢?其中很重要一部分是因为人类基因组计划。人类基因组,越做越发现一个问题:我们本来以为,人少说也有2-3十万个基因,才够解释我们这么多种多样的性状。可是测序完了发现要远远少于这个数字,也就预期的十分之一那么多。那么每个基因的精细调节,各个基因间的协作,就变得重要了。还有,一定有一些遗传信息,是不包含在DNA碱基对序列里的。
这些其实以前也有人想过。比如说T cell的分化。有些细胞表达这一套基因,有些细胞表达那一套基因,但是这两种细胞都来自于同一个未分化细胞。也就是说本来两组基因都是可以被表达的,那么是什么决定了在某些细胞里表达这部分而关闭了那部分,在另一些里表达那部分而关闭了这部分? 而且,一旦分化了就再也会不去, 如果只是传统上理解的基因调控,是什么让他回不去的?现在已经清楚,那些不表达的部分,都高度methylated了,染色质紧密包装,成了heterochromatin,不能表达了(这里有请免疫组选手出场)

这样人们就预期,一定有什么信息存在,跟遗传密码一样,是可遗传的,决定基因表达的,甚至可编码的,但是又不是包含在DNA碱基对里。

人们首先想到的是直接发生在DNA上的甲基化(DNA methylation)。因为这个变化只发生在DNA碱基一个C接一个G的地方,所以自动的具有编码功能。而且是附着在DNA上的,在不改变DNA序列的情况下使得DNA的编码功能更加复杂。还有,人们在体外可以复制methylated DNA,那些methylation位点和他们上面的methylation都能被复制下来,证明它确实是可遗传的。

可是这还远远不够。
很快人们就想到了被忽略了几十年的组蛋白。每一百多个DNA碱基对组成的绳子,可以包裹8个组蛋白组成的球,形成一个核小体(nucleosome)。核小体是染色质的基本单位。染色质就是一大串这种小珠子,绕来绕去。这些组蛋白在成球的时候,外头还留着小尾巴。这些小尾巴上的氨基酸位点又可以被共价修饰。前头说了,修饰过的组蛋白,跟绳子的缠绕,紧密程度发生改变。那么在不同的位点上的不同修饰,又形成了一套新的密码,这个pattern,有个名字叫做histone code. 这个理论叫做histone coding theory. 提出来这个理论的人叫做david allis,一篇很短的综述文章发表在01年的science上,叫做translating the histone code。我们家网慢,被昨天晚上的冰雹摧毁了。我就不给连接了。

当然这个东西后来又发展了,有些证据证明同一类共价修饰在每个位点的作用差不多,所以这套密码没那么复杂;同时也有人证明虽然都是乙酰化,但是在每个位点的作用都不同,它就是那么复杂,云云。

同时还有其他东西可能也具有这样的特征:不是DNA,可遗传,编码,指导转录调控。但是我们现在说到epigenetics,指的基本上就是DNA methylation和histone modification.

Epigenetics如何参与transcription regulation,我说的不好,干巴巴,不过我有一个同学给人解释过,比我说的清楚多了。我给搬过来。


[quote]关于这epigenetics啊,简单的讲,它就是epi-和genetics的一合成词,genetics是啥,地球人都知道,“遗传学”,epi-是“上,外,后”的字根,所以简单的说epigenetics就是“外(部)遗传学”或“后遗传学”,也可以叫“附加遗传学”“派生遗传学”。

Posted: 2007-02-28 6:36
by 猫咪头
Transcription is the first step of protein making, i.e. "gene expression".

Old knowledge A): we express the genes we get from our parents.
Example: You mom is A blood type , your dad is AB. You got O allele from mom, B allele from dad. You express both allele of this gene, your blood type is AB.

Contrary to commom mis-comception of we each have a different book of genetic coding, most of the DNA coding of human being are similiar. Most of the "distinct human features" are realized by difference in the amount of protein certain cell make, and the duration of protein making (gene expression).

Known bio-fact B): CpG island (which is a long CGCGCGCGCGCG sting usually upsteam of a DNA sequence that code for a meaningful protein), when methylated, espetially if the histone protein that helps DNA form the double helix structure became methylated, become regid and "closed". Since normal gene expression (a bunch of enzymes bind and glide through the DNA to make a mRNA according to the gene sequence) need the DNA int he local region to be "bindable" and "open". Thus heavely methylated region is usually inactive in gene expression, i.e. genes in the region is shut-down.

The "shut-down" can be reversed, and often is during the daily life of the cell. {For each cell, there are also regions that is almost permenantly repressed. For example, your neuron does not need to express antiboby, hence related regions is always shut-down.}

But each life has a starting point. The fertilized egg is a one-cell organism. The methylation state of each gene in the original fertilized egg, as well as the 2 copys of DNA sequences, is what we inherited from our parents.


Here, the author claimed that early childhood experience can change methylation state of sertian genes.
Yes, interesting idea.
But each infant is a multi-cell, quite old organism from a genetic view. Such difference is too easy to occur for it to be solid enough to draw the (scientific) conclusion.

What I don't like is how the whole story is sci-fied by news writers. The little data cannot be strenched that much.

Posted: 2007-02-28 7:44
by Jun
明白了(liao)。谢谢。本来让我迷糊的是为什么森林火焰描述的老鼠实验能知道一定是epigenetics影响的而不是普通的signal transduction,因为哈,我以为持久的神经细胞/生理特征可以通过短暂外界刺激--基因表达--神经wiring--长期记忆,就直接达到持久的表征(长大后的hysteria),不需要持久的gene expression regulation。

猫咪头,这是两个不同的研究,一个是在人里面的,一个是在老鼠里面的,完全不能证明,在老鼠里面的基因调整,跟人类婴儿的infant attachment disorder是一样的途径。但是,infant attachment disorder对成年后性格的某一方面(interpersonal comfort, trust and security)有明显的持久的影响,是一个被许多不同试验证明过的现象。你要说彻底地没有争议地证明过了,也没那么肯定,不过科学里大多数的理论都不是被彻底无争议地证明过,包括进化论。只能说,现有证据支持这个理论。

我最上面引用的报道,sample size只有78个人,但是它不是孤立存在凭空提出的理论,而是在现有的其他证据之上,多出一个数量有限但是时间很长的新证据。一个理论如果有不同方向来的多个corroborating evidence,它的真实性就更高。在心理学和精神医学方面,因为测量手段,ethics,和其他的种种困难,很少能做特别"高级"的试验,跟新药临床试验和"主流"疾病研究的条件没法比,如果拿它们的研究要求来衡量心理科的研究,那基本上所有的理论都不能提了。

Posted: 2007-02-28 13:14
by 猫咪头
Oh, my, I can't tell one is in mouse and the other in human? Now I offically fit the joke of a molecular biologist.

Posted: 2007-02-28 13:28
by 猫咪头
Compare to studies in Evolution: People measured the hight of Mount everest, and the result has an uncertainty of several meters.

This stuty (the one in human): people measured the length of snakes, and the result has an uncertainty of several meters.


That snakes are harder to measure and that they courage is admirable (yes I do think so), do not add credit to their data.

And claiming "but nothing is certain" is just dirty fighting.

my new motto: I can't be 100% sure, but I can be 95% confident. 8)

Posted: 2007-02-28 13:32
by Jun
I disagree with your analogy of proportions in this particular case.

Posted: 2007-03-12 17:25
by hh
Last week I chose this topic as my epigenetics class assignment. Then I dug out the papers »ðÑæ mentioned. The study was since 50's of last century....The old days experiments are mostly about postnatal handling. Michael Meaney Lab did a lot of work. Then in 1997 there is a more direct evidence of epigenetics.
Liu D, Diorio J, Tannenbaum B, Caldji C, Francis D, Freedman A, Sharma S, Pearson D, Plotsky PM, Meaney MJ. Maternal care, hippocampal glucocorticoid receptors, and hypothalamic-pituitary-adrenal responses to stress. Science 1997; 277: 1659-62. [So, »ðÑæ, it is rat, not mice, I think that is why we could not find the paper first]

Anyone interested could look through it.

This is the further molecular level evidence.
Weaver IC, Cervoni N, Champagne FA, D'Alessio AC, Sharma S, Seckl JR, Dymov S, Szyf M, Meaney MJ. Epigenetic programming by maternal behavior. Nat Neurosci . 2004 Aug 1 ; 7(8):847-54.

Posted: 2007-03-12 17:47
by 森林的火焰
Thanks a lot! :lol: I started questioning my memory, though it is pretty questionable...

Posted: 2007-03-25 0:55
by 85192820
科幻??