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Medical 50-0-50 rule

  1. Nov 18, 2009 #1

    Pythagorean

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    the rule:

    how adult personalities/intelligence turn out is due to:
    50% genetics
    0% family environment (how they're raised)
    50% other environment (peers, media?, etc.)

    the question:

    1) how seriously is this taken?

    2) how do you divide family environment from other environment? I mean, to some extent, don't your decisions as a parent heavily influence their "other" environment. From who you allow them to hang out with to where you chose to live and put them through school?

    3) Why? I know this will involve a lot of conjecture. My opinion is that children see their parents as more of an internal life-support system than part of the "real world".
     
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  3. Nov 18, 2009 #2
    not familiar with that as a rule, but i think about all we've got to go on are twin studies where they got split up early in life. from what i remember, genetics is a huge factor in how people turn out.
     
  4. Nov 26, 2009 #3
    That is nonsense. You can't say that familial influence is nothing. It's at least 1%.
     
  5. Nov 26, 2009 #4

    Moonbear

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    I've never heard of such a rule either. And, there certainly is an influence of rearing on behavior. If there wasn't, scientists wouldn't go to such great lengths to cross-foster rats to elimate that bias of maternal interactions/rearing in behavior experiments. Why on earth would other environment be so influential and family environment not be? It doesn't even make sense.
     
  6. Nov 28, 2009 #5

    Pythagorean

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    Well, that's why it's so interesting, because it's counter-intuitive. Of course, we don't like to hear it as parents, but that doesn't mean it's false.

    http://www.psychologytoday.com/blog...ule-why-parenting-has-virtually-no-effect-chi

     
  7. Nov 28, 2009 #6

    Pythagorean

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  8. Nov 28, 2009 #7
    This is an astonishing notion, and likely as misguided as theories from the sixties which attempted to blame schizophrenia on the parents. Unless of course trauma is removed from the equation. Seems like an effort to blame aberrant behavior on the bad kids. Not discounting peer influence, vut it seems a bit of a stretch. I'd probably go 70/15/15 in order of genes, parents, and peers.
     
  9. Nov 28, 2009 #8

    Andy Resnick

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  10. Nov 28, 2009 #9

    Evo

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    Unfortunately this is the old "nature versus nurture" argument made by racists and eugenicists that argue that IQ is primarily genetic in order to push their agendas to wipe out races and people of "lower IQ" that are incapable of producing intelligent offspring, in their opinion.

    Neried and I fought this battle for at least 2 years here against those that were pushing this train of thought. We won.
     
  11. Nov 28, 2009 #10
    i don't think it is exactly that. genetics may determine your neurochemistry, and that may have a huge factor on your "personality". not that personality should be taken as other things, tho, like "character"/behaving morally. i'd expect genetics to have a big influence on whether a person is say, gregarious or a risk-taker.

    IQ? i'm not even sure i know exactly what that means. but perhaps genetics do play a role in predisposing people for certain tasks. we do know that it can determine what muscles you may or may not have. if you're white, you http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1467925/" [Broken], but not if you're black. and if musculo-skeletal structure is affected, there's no reason to believe that there aren't statistical differences in brain structure.
     
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  12. Nov 28, 2009 #11

    ideasrule

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    What? So you're claiming that Judith Rich is advocating eugenics because he believes genetics is as important as environmental factors in determining intelligence? I can't believe you would make such an accusation based on a person's scientific beliefs! There's PLENTY of evidence proving genetics has a major role in determining intelligence, and PLENTY of evidence proving environmental factors play a major role as well. Just because this guy believes the split is 50-50 between genetics and environment instead of 49-51 or 40-60, he's a racist and eugenicist?

    This kind of ad hominem attack is typical of religion and politics, but has no place in science.
     
  13. Nov 28, 2009 #12

    D H

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    Evo never said that. Read what she said.
     
  14. Nov 28, 2009 #13

    ideasrule

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    I apologize if I misunderstood, but she said:

    Unfortunately this is the old "nature versus nurture" argument made by racists and eugenicists that argue that IQ is primarily genetic in order to push their agendas to wipe out races and people of "lower IQ" that are incapable of producing intelligent offspring, in their opinion.

    I see that she could be saying that Rich's scientific opinion is well-founded, so it's unfortunate that many racists/eugenicists share the same opinion. The phrasing ("THIS is the old ... argument") made me think "this" referred to the articles being discussed.
     
  15. Nov 28, 2009 #14

    Evo

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    :rofl: I was simply telling people this was referring to the old nature vs nurture argument, since they didn't understand and thought they've never heard of it. You know the famous twin experiments? I don't think pythagorean is a eugenicist or is calling for racial cleansing, I never said that.

    But if anyone here thinks we're going to go down the racist/eugenics road, nope.
     
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  16. Nov 29, 2009 #15
    Actually, Evo, I don't see it as nature vs nurture so much as nurture vs nurture: the claim is that most, if not all of the environmental inflluences are coming from the kids' peers and general socializing influences of whatever culture he/she may be reared in, and very little from the parents/immediate family.

    I find it an astonishing notion in that practically every screwed up kid I have met has guess what, screwed up parents. At least within western psychiatry, there has been a back and forth re the effect of the parents--Freudian's believe that just about every problem can be traced back to the collective influence of traumas, small and large, intended or not, on the part of the parents. More recent psychoanalytic theory tends to get away from this extreme view with folks like Melanie Klein suggestng that a parent only need be good enough for crucial development milestones to be successfully achieved.

    If you buy into the latter notion as I do, (and I'm not much of a fan of psychoanalysis) it may well be that peers, teachers and others become the primary shapers of the child's personality. And maybe the percentage of really screwed up parents is small enough that truly bad parenting gets washed out in a study of this type. I believe that's why both I and Andy R were questioning the effects of abuse. I've often wondered how the kibbutzes did in this regard as presumably the effects of lousy biological parents would be softened by the large amount of contact with healthier members, just as having a good granny or aunt here can ameliorate the effeects of the primary caregivers. At least that was my take. There were too many other confounding issues with Kibbutzism in my limited knowledge of the subject to draw any conclusions re the question at hand.
     
  17. Nov 29, 2009 #16

    Evo

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    I have to say I agree. I've never agreed with the nature vs nurture where genectics was the overwhelming deciding factor and environment given almost no importance.
     
  18. Nov 29, 2009 #17

    OmCheeto

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    I would say the rule should be 50-50-0.

    I'm a firm believer in the http://en.wikipedia.org/wiki/Up_Series" [Broken] rule.

    Actually, I grew up, as did the 7-Up kids, when TV was a fairly benign* part of life.

    With people now using TV as a baby sitter, the rule might now be 40-40-20.

    Do not let Vera Lynn watch TV until she is 7! It will rot her mind.



    *as in relating to tumors.
     
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  19. Nov 29, 2009 #18

    Pythagorean

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    Firstly, this idea was taught in the open Yale psychology courses that I've been watching.

    Second, in the case of abuse and other extreme traumas, there lies an exception. It's known that many serial killers suffered brain damage at a critical time in their youth in combination with physical and mental abuse. So, yeah, if you beat your kid, you can overcome the 50-0-50 rule. I'm also pretty sure that if you don't give your kid love and care, they will be emotionally underdeveloped, which leads to learning development problems.

    However, if we assume a sort of standard situation, where the kid doesn't get abused, gets love and care, is given proper nutrition, shelter, etc, etc, etc, I can't dismiss the 50-0-50 rule quite yet (I mean, it's based on evidence, and I haven't found any evidence countering it, but I'd welcome any)

    My opinion about the reason for the 50-0-50 rule is that, basically, kids get bored with their parents rather early. We know that the brain gets bored with repetitive stimuli, the dopamine levels respond with less and less intensity every time and depending on the frequency of the stimuli. From this, I would assume that it's not too far fetched that the neuroplasticity of the young becomes less and less receptive of the constant stimuli of family until the point where, later in life (remember that the rule applies to the developed adult, no the developing child) the multiple shifting stimuli of the outer-world (outside the family) has a much more dramatic effect on the children than their parents did because it's more "interesting" to the brain than what the brain considers the "norm".
     
  20. Nov 29, 2009 #19

    Andy Resnick

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    It's still a straw man argument- you are asking us to believe something is true in spite of clear counterexamples. Minimizing or wishing away the counterexamples is ignoring truth in favor of dogma.

    The same is true in physics- Classical mechanics is 100% true if you ignore those pesky orbitals... :)
     
  21. Nov 29, 2009 #20
    The situation may be even more interesting and complicated than what you propose. I just read a good review found in this issue of The http://www.theatlantic.com/doc/200912/dobbs-orchid-gene" that has been brewing for some time.

    I recommend reading the article but will try to summarize: There is a good deal of neurobilogical emerging evidence which helps to explain what has heretofore been a puzzle: Why are illnesses such as depression, ADHD, sociopathic behavior so common in humans? These are all neurobahavioral disorders which appear to be tightly associated with certain polymorphic alleles, the most notable being the serotonin transporter. If these are "bad" genes, why hasn't the frequency diminished over time? What good do they serve so as to persist in spite of what should be strong selective pressure?

    In the last 10-15 years, we may be nearing an answer. As it turns out there is accumulating evidence (both primate and human) which demonstrates a paradox: these genes in a normal and especially a poor environment are a deinite liability. But when such an individual is placed in a supermom environment, what was once a disadvantage now becomes a clearcut advantage. They mate "better", forge better social alliances, and rise higher in dominance heirarchies. The other fascinoma is that the two species of primate which are able to migrate and penetrate new environments are the Rhesus monkey and humans, both of which demonstrate this striking polymorphism of genes so fundamental to neurotransmitter processing. In a simple minded way it reminds me of the famed sickle cell gene which in a single dose confers resistance to malaria, while in a double dose leads to a crippling and atal disease. Only this is much more fun!
     
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  22. Nov 29, 2009 #21

    Moonbear

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    I really don't know how possible it is to quantify the relative percentages of contribution from genetics vs social or other environmental influences; I don't think we have the sufficient understanding of all the genetic involvement yet to subtract that out from the "equation" and figure out how much is left that must be attributed to environmental factors. And, I would suspect that the relative contribution of different types of social and environmental influences would vary considerably depending on just what those influences were. I think it makes no sense at all to say there is ZERO parental influence.

    Afterall, if parents are so overly strict with a child and completely isolate them from other social influences, how can that NOT have an influence on that child's behavior, and not a MAJOR influence? On the other hand, a child with a range of social experiences may not have any large contribution from any one of them, but a small contribution from each, such that yes, the parental contribution may be fairly small in the grand scheme of sources they have accessed to form their views.

    And, it may even get more complicated when some of the genetics is affecting affiliative behavior, parental bonding, etc., so that the genetics themselves would alter the relative weight of outside influences.
     
  23. Nov 29, 2009 #22
    MB, Your intuition seems spot on--if you have a few moments, read the thought provoking article I cited above in The Atlantic. Genes influencing behavior, mom influencing expression of genes, environmental stress affecting mom, in turn influencing whether the genes are adaptive or maladaptive. Game theory, evolution, psychology, molecular biology and culture all rolled up in one big inextricable ball of nested feedback loops like spaghetti code.
     
  24. Nov 29, 2009 #23
    Addressing Pythagorean’s mention of ‘serial killers’. I present only a small section from a very large document. I should make it very clear that I don't take this topic lightly. It is very serious!

     
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  25. Nov 30, 2009 #24

    Andy Resnick

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    I completely agree with this. I wonder if this discussion also highlights a difference in culture- biologists generally report order-of-magnitude qualitative results, while physicists tend to require high precision, quantitative results.
     
  26. Nov 30, 2009 #25

    Pythagorean

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    Just to make sure we're clear here, skills and cognitive development aren't necessarily what's being compared here. The comparisons are of intelligence (specifically general intelligence as opposed to specialized intelligence) and the "big five", which are the standardized personality traits (it's an easy google, "big five"). As far as I know, that's all that's being compared. So it's about general intelligence and personality, not specialized abilities or skills (which obviously can be taught by parents).

    Andy
    I'm not asking you to believe it. I'm actually consulting the professional psychologists here for their opinion (if you'll read the OP) I was actually surprised that no one has heard of it. And being so, I'm not just going to immediately dismiss it, especially because no one has heard of it and the responses here are gut reactions and haven't been completely thought out yet, so I'm going to give it a chance.

    I am somewhat skeptical of it myself. I realize that it's a generalization and an 'order of magnitude' approximation. Also, similar to what Moonbear said (but not quite), parents can move to where the social atmosphere is to their liking, which gives them a bit of control... in the end, it's hard to control who your kids hang out with (I know this from having been a teenager and having lots of teenage friends, all of whose parents didn't like us hanging out with each other).

    But think about what happens in this scenario. Generally, the kids are socially underdeveloped. In other words, they're parents have stunted their social development by giving them no social environment. This only supports the thesis (accepting Resnick's implication that it's not actually 0%... in fact, I think the point is to outline the importance of outside-the-family social environment, and how much more influential it is than the environment inside the family. They say "virtually none" when you read the articles, not "ZERO")

    But this would be an interesting study.

    Also, remember that this study is about the end result, the adult, not the adolescent phase of their lives. Another assumption that is accepted in the psychology field is that once you're a fully developed adult, your personality and intelligence scores stay pretty constant over time. Prior to that, not so much.

    ViewsOfMars

    what's your point, exactly?
     
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