Personality & Intelligence: The 50-50 Rule

[Pythagorean]

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".

 

[Proton Soup]

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.

 

[rainbow93]

That is nonsense. You can't say that familial influence is nothing. It's at least 1%.

 

[Moonbear]

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.

 

[Pythagorean]

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.

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

In her 1995 article, and then in her 1998 book The Nurture Assumption: Why Children Turn Out the Way They Do, Harris methodically demolishes the universally held assumption that how parents raise their children is a major determining factor in how they turn out. Harris instead argues that parental socialization has very little effect on children because they are mostly socialized and influenced by their peers. While Harris’s conclusion was enormously controversial and widely condemned by politicians and the media alike, it is in fact corroborated by behavior genetic research.

 

[Pythagorean]

Here's another article with the same conclusion:
http://www.nytimes.com/2008/09/04/garden/04twins.html?_r=2&oref=slogin

 

[denverdoc]

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.

 

[Andy Resnick]

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

I have to say that's an idiotic article- what about children who are abused by parents?

Or does the author claim the best parents can do is "no harm"?

 

[Evo]

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.

 

[Proton Soup]

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.

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/" , 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.

 

[ideasrule]

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.

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.

 

[D H]

What? So you're claiming that Judith Rich is advocating eugenics because he believes genetics is as important as environmental factors in determining intelligence?

Evo never said that. Read what she said.

 

[ideasrule]

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.

 

[Evo]

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/" , 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.

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.

: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.

 

[denverdoc]

: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.

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.

 

[Evo]

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.

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.

 

[OmCheeto]

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

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

 

[Pythagorean]

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".

 

[Andy Resnick]

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... :)

 

[denverdoc]

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".

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!

 

[Moonbear]

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.

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 anyone 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.

 

[denverdoc]

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 anyone 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.

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.

 

[ViewsofMars]

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!

Serial Murder — Multi-Disciplinary Perspectives for Investigators
Behavioral Analysis Unit-2
National Center for the Analysis of Violent Crime
Critical Incident Response Group
Federal Bureau of Investigation
[snip]

Myth: Serial killers want to get caught.

Offenders committing a crime for the first time are inexperienced. They gain experience and confidence with each new offense, eventually succeeding with few mistakes or problems.

While most serial killers plan their offenses more thoroughly than other criminals, the learning curve is still very steep. They must select, target, approach, control, and dispose of their victims. The logistics involved in committing a murder and disposing of the body can become very complex, especially when there are multiple sites involved.

As serial killers continue to offend without being captured, they can become empowered, feeling they will never be identified. As the series continues, the killers may begin to take shortcuts when committing their crimes. This often causes the killers to take more chances, leading to identification by law enforcement. It is not that serial killers want to get caught; they feel that they can’t get caught.

II. Definition of Serial Murder
[snip]

The different discussion groups at the Symposium agreed on a number of similar factors to be included in a definition. These included:

• one or more offenders
• two or more murdered victims
• incidents should be occurring in separate events, at different times
• the time period between murders separates serial murder from mass murder
In combining the various ideas put forth at the Symposium, the following definition was crafted:
Serial Murder: The unlawful killing of two or more victims by the same offender(s), in separate events.

III. Causality and the Serial Murderer

Following the arrest of a serial killer, the question is always asked: How did this person become a serial murderer? The answer lies in the development of the individual from birth to adulthood. Specifically, the behavior a person displays is influenced by life experiences, as well as certain biological factors. Serial murderers, like all human beings, are the product of their heredity, their upbringing, and the choices they make throughout development. Causality, as it relates to the development of serial murderers, was discussed at length by the Symposium attendees.
Causality can be defined as a complex process based on biological, social, and environmental factors. In addition to these factors, individuals have the ability to choose to engage in certain behaviors. The collective outcome of all of these influences separates individual behavior from generic human behavior. Since it is not possible to identify all of the factors that influence normal human behavior, it similarly is not possible to identify all of the factors that influence an individual to become a serial murderer.

Human beings are in a constant state of development from the moment of conception until death. Behavior is affected by stimulation received and processed by the central nervous system. Neurobiologists believe that our nervous systems are environmentally sensitive, thereby allowing individual nervous systems to be shaped throughout a lifetime.

The development of social coping mechanisms begins early in life and continues to progress as children learn to interact, negotiate, and compromise with their peers. In some individuals the failure to develop adequate coping mechanisms results in violent behavior.

Neglect and abuse in childhood have been shown to contribute to an increased risk of future violence. Substance abuse can and does lead to increased aggression and violence. There are documented cases of people who suffered severe head injuries and ultimately become violent, even when there was no prior history of violence.

Symposium attendees agreed that there is no single identifiable cause or factor that leads to the development of a serial killer. Rather, there are a multitude of factors that contribute to their development. The most significant factor is the serial killer’s personal decision in choosing to pursue their crimes.

There were several additional observations made by the attendees regarding causality:

• Predisposition to serial killing, much like other violent offenses, is biological, social, and psychological in nature, and it is not limited to any specific characteristic or trait.
• The development of a serial killer involves a combination of these factors, which exist together in a rare confluence in certain individuals. They have the appropriate biological predisposition, molded by their psychological makeup, which is present at a critical time in their social development.
• There are no specific combinations of traits or characteristics shown to differentiate serial
killers from other violent offenders.
• There is no generic template for a serial killer.
• Serial killers are driven by their own unique motives or reasons.
• Serial killers are not limited to any specific demographic group, such as their sex,
age, race, or religion.
• The majority of serial killers who are sexually motivated erotized violence during development. For them, violence and sexual gratification are inexplicably intertwined
in their psyche.
• More research is needed to identify specific pathways of development that produce serial killers.

IV. Psychopathy and Serial Murder

Attendees at the Serial Murder Symposium agreed that there is no generic profile of a serial murderer. Serial killers differ in many ways, including their motivations for killing and their behavior at the crime scene. However, attendees did identify certain traits common to some serial murderers, including sensation seeking, a lack of remorse or guilt, impulsivity, the need for control, and predatory behavior. These traits and behaviors are consistent with the psychopathic personality disorder. Attendees felt it was very important for law enforcement and other professionals in the criminal justice system to understand psychopathy and its relationship to serial murder.

Psychopathy is a personality disorder manifested in people who use a mixture of charm, manipulation, intimidation, and occasionally violence to control others, in order to satisfy their own selfish needs. Although the concept of psychopathy has been known for centuries, Dr. Robert Hare led the modern research effort to develop a series of assessment tools, to evaluate the personality traits and behaviors attributable to psychopaths.

Dr. Hare and his associates developed the Psychopathy Check List Revised (PCL-R) and its derivatives, which provide a clinical assessment of the degree of psychopathy an individual possesses. These instruments measure the distinct cluster of personality traits and socially-deviant behaviors of an individual, which fall into four factors: interpersonal, affective, lifestyle, and anti-social.

The interpersonal traits include glibness, superficial charm, a grandiose sense of self-worth, pathological lying, and the manipulation of others. The affective traits include a lack of remorse and/or guilt, shallow affect, a lack of empathy, and failure to accept responsibility. The lifestyle behaviors include stimulation-seeking behavior, impulsivity, irresponsibility, parasitic orientation, and a lack of realistic life goals. The anti-social behaviors include poor behavioral controls, early childhood behavior problems, juvenile delinquency, revocation of conditional release, and criminal versatility. The combination of these individual personality traits, interpersonal styles, and socially deviant lifestyles are the framework of psychopathy and can manifest themselves differently in individual psychopaths.

Research has demonstrated that in those offenders who are psychopathic, scores vary, ranging from a high degree of psychopathy to some measure of psychopathy. However, not all violent offenders are psychopaths and not all psychopaths are violent offenders. If violent offenders are psychopathic, they are able to assault, rape, and murder without concern for legal, moral, or social consequences. This allows them to do what they want, whenever they want.

The relationship between psychopathy and serial killers is particularly interesting. All psychopaths do not become serial murderers. Rather, serial murderers may possesses some or many of the traits consistent with psychopathy. Psychopaths who commit serial murder do not value human life and are extremely callous in their interactions with their victims. This is particularly evident in sexually motivated serial killers who repeatedly target, stalk, assault, and kill without a sense of remorse. However, psychopathy alone does not explain the motivations of a serial killer.

Understanding psychopathy becomes particularly critical to law enforcement during a serial murder investigation and upon the arrest of a psychopathic serial killer. The crime scene behavior of psychopaths is likely to be distinct from other offenders. This distinct behavior can assist law enforcement in linking serial cases.
.
Psychopaths are not sensitive to altruistic interview themes, such as sympathy for their victims or remorse/guilt over their crimes. They do possesses certain personality traits that can be exploited, particularly their inherent narcissism, selfishness, and vanity. Specific themes in past successful interviews of psychopathic serial killers focused on praising their intelligence, cleverness, and skill in evading capture.

Attendees recognized that more research is needed concerning the links between serial murder and psychopathy, in order to understand the frequency and degree of psychopathy among serial murderers. This may assist law enforcement in understanding and identifying serial murderers.

V. Motivations and Types of Serial Murder: The Symposium Model

Over the past twenty years, law enforcement and experts from a number of varying disciplines have attempted to identify specific motivations for serial murderers and to apply those motivations to different typologies developed for classifying serial murderers. These range from simple, definitive models to complex, multiple-category typologies that are laden with inclusion requirements. Most typologies are too cumbersome to be utilized by law enforcement during an active serial murder investigation, and they may not be helpful in identifying an offender.
The attendees at the Symposium discussed the issues surrounding motivation and the use of typologies to categorize varying types of serial murder. Identifying motivations in the investigation of a crime is a standard procedure for law enforcement. Typically, motivation provides police with the means to narrow the potential suspect pool.

The same logical steps are taken when investigating homicide cases. As most homicides are committed by someone known to the victim, police focus on the relationships closest to the victim. This is a successful strategy for most murder investigations. The majority of serial murderers, however, are not acquainted with or involved in a consensual relationship with their victims.

For the most part, serial murder involves strangers with no visible relationship between the offender and the victim. This distinguishes a serial murder investigation as a more nebulous undertaking than that of other crimes. Since the investigations generally lack an obvious connection between the offender and the victim, investigators instead attempt to discern the motivations behind the murders, as a way to narrow their investigative focus.

Serial murder crime scenes can have bizarre features that may cloud the identification of a motive. The behavior of a serial murderer at crime scenes may evolve throughout the series of crimes and manifest different interactions between an offender and a victim. It is also extremely difficult to identify a single motivation when there is more than one offender involved in the series.
The attendees at the Symposium made the following observations:
• Motive generally may be difficult to determine in a serial murder investigation.
• A serial murderer may have multiple motives for committing his crimes.
• A serial murderer’s motives may evolve both within a single murder as well throughout the murder series.
• The classification of motivations should be limited to observable behavior at the crime scene.
• Even if a motive can be identified, it may not be helpful in identifying a serial murderer.
• Utilizing investigative resources to discern the motive instead of identifying the offender may derail the investigation.
• Investigators should not necessarily equate a serial murderer’s motivation with the level of injury.
• Regardless of the motive, serial murderers commit their crimes because they want to. The exception to this would be those few killers suffering from a severe mental illness.
To assist law enforcement in narrowing the pool of suspects, attendees at the Symposium suggested that broad, non-inclusive categories of motivations be utilized as guidelines for investigation. The following categories listed below represent general categories and are not intended to be a complete measure of serial offenders or their motivation:
• Anger is a motivation in which an offender displays rage or hostility towards a certain subgroup of the population or with society as a whole.
• Criminal Enterprise is a motivation in which the offender benefits in status or monetary compensation by committing murder that is drug, gang, or organized crime related.
• Financial gain is a motivation in which the offender benefits monetarily from killing. Examples of these types of crimes are “black widow” killings, robbery homicides, or multiple killings involving insurance or welfare fraud.
• Ideology is a motivation to commit murders in order to further the goals and ideas of a specific individual or group. Examples of these include terrorist groups or an individual(s) who attacks a specific racial, gender, or ethnic group.
• Power/thrill is a motivation in which the offender feels empowered and/or excited when he kills his victims.
• Psychosis is a situation in which the offender is suffering from a severe mental illness and is killing because of that illness. This may include auditory and/or visual hallucinations and paranoid, grandiose, or bizarre delusions.
• Sexually-based is a motivation driven by the sexual needs/desires of the offender. There may or may not be overt sexual contact reflected in the crime scene.

An offender selects a victim, regardless of the category, based upon availability, vulnerability, and desirability. Availability is explained as the lifestyle of the victim or circumstances in which the victim is involved, that allow the offender access to the victim. Vulnerability is defined as the degree to which the victim is susceptible to attack by the offender. Desirability is described as the appeal of the victim to the offender. Desirability involves numerous factors based upon the motivation of the offender and may include factors dealing with the race, gender, ethnic background, age of the victim, or other specific preferences the offender determines.
[snip]
###
http://www.fbi.gov/publications/serial_murder.htm#two

 

[Andy Resnick]

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 anyone 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.

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.

 

[Pythagorean]

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).

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?

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?

 

[denverdoc]

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).


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 don't think that it is quite fair assessment--I provide a response with reference to cutting edge research involving both animal studies as well as on humans, that purports to show that the most potent neurobehavioral genes yet characterized can be either a disadvantage or advantage, based solely on the fitness of the mother is "chopped liver.

 

[Pythagorean]

I don't think that it is quite fair assessment--I provide a response with reference to cutting edge research involving both animal studies as well as on humans, that purports to show that the most potent neurobehavioral genes yet characterized can be either a disadvantage or advantage, based solely on the fitness of the mother is "chopped liver.

It doesn't seem to have anything to do with the point though. You've said nothing about intelligence and personality as they are defined in psychology.

I do wish I could see exactly how this study (the 50-0-50 one) was performed, honestly. I will express that I don't trust the exact numbers, but I can see how peers would be significantly more influential than parents (socially, not genetically) in terms of personality and general intelligence. In my anecdotal experience, my peer group pretty much ignored our parents ideas. We think they're old and out-dated. Of course, I come from a pretty conservative town.

 

[Pythagorean]

Another note. I'm NOT whatsoever saying that parents aren't important in child-rearing. I firmly believe that (besides food, shelter, and the obvious) love and care are very important to your child's development. An article (link below) I recently read stated how cognitive development is thwarted without a solid emotional development. Monitoring your child for performance and tracking milestones and testing their performance doesn't seem to be near as beneficial to their cognitive development as emotional development is. The article also says that even technical skills, like math, are initially learned through the emotions.

http://www.psychologytoday.com/articles/200704/daycare-raising-baby

also, is Psychology Today considered a credible source? I've been carrying on like it is. If it's not, I apologize.

 

[hamster143]

I can't say anything about personality. It's a vague and imprecisely defined subject. As far as intelligence, the effect is not 50-0-50. As far as I know, studies suggest something like 65-0-35 or even higher. But the catch is that only about half of these 65% is directly inherited from parents. The other half is randomly generated at the moment of conception. That's the reason why identical twins have much higher correlations with each other than either fraternal twins or normal siblings.

The whole nonshared environment thing is a big puzzle. By definition, nonshared environment is that which would not be shared by a pair of same-sex twins. It does not have much to do with peers (because influence of peers is, to a large degree, shared and correlated with parents' socioeconomic status). It does not have anything to do with TV, access to books, quality of schooling, ... It may be more like butterfly effect, where initial random impressions that occur in the early age result in different interests, preferences, thinking processes.

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.

It's not that at all. It's more akin to the global warming debate, where solid and growing body of impartial scientific evidence is being ignored by a group of vocal activists who dislike the conclusions that stem from that evidence.

I have to say that's an idiotic article- what about children who are abused by parents?

There's no reason to expect abused children to be less intelligent than normal children. Just as there's no reason to expect them to be less capable of, say, running marathons or lifting weights. Unless abuse comes to the point of nutritional deficiencies.

 

[Pythagorean]

There's no reason to expect abused children to be less intelligent than normal children.

That's a good point, I wonder what the evidence on this suggests. I wonder if abused children tend to score the same way on a big five personality test or not. If that were true, than I would have no choice but to accept that abuse alters personality.

If, however, abused children all have different personalities, than further research would be required to control.

 

[denverdoc]

It doesn't seem to have anything to do with the point though. You've said nothing about intelligence and personality as they are defined in psychology.

I do wish I could see exactly how this study (the 50-0-50 one) was performed, honestly. I will express that I don't trust the exact numbers, but I can see how peers would be significantly more influential than parents (socially, not genetically) in terms of personality and general intelligence. In my anecdotal experience, my peer group pretty much ignored our parents ideas. We think they're old and out-dated. Of course, I come from a pretty conservative town.

Here again I disagree. What I consider personality is largely about traits like impulsivity, anxiety, introversion/extroversion, depression/innovation, exploration and innovation vs preservation of the status quo. These are exactly the traits influenced by these rogue or orchid genes.

Let me try to bring it home with the simple observation that many of the most "successful" individuals in our society are more often than not highly vain, impetuous, individuals willing to take great chances under favorable circumstances, and yet the same genes land their owners in highly disproportionate numbers in prison or condemn to an early death. What is the difference? Is it simply fortuitous? The studies, whether animal or man, seem to suggest that the biggest operative influence as to whether the roll comes out snake eyes or box cars is mom and early nurturance.

Even more mindbending is that these polymorphic genes exist in two primate species--the rhesus monkey and man--the only two primate species that are not to be relegated to a narrow and comfortable ecological niche. I would say that this adds up to a very powerful argument in favor of mom if she is able to tip the scales that take a debt ridden gene and make it advantagous is arguably the only reason we are not still huddled about a fire on the savannah--that is had we even mastered fire.

Intelligence IMHO is too narrowly defined as the ability to rapidly process certain types of info in particular ways. That Steven Haawking is a wunderkind is beyond doubt, can the same be said for a Donald Trump, Barbra Walters, or dare I say Sarah Palin? From an evolutionary perspective, the answer seems clear. I think this muddies the water horribly when talking about intelligence and how people come to possesses it as there is no clear way to measure it, as no where do I see it measure evolutionary fitness which must be considered the ultimate "intelligence."

 

[Pythagorean]

Here again I disagree. What I consider personality is largely about traits like impulsivity, anxiety, introversion/extroversion, depression/innovation, exploration and innovation vs preservation of the status quo. These are exactly the traits influenced by these rogue or orchid genes.

Let me try to bring it home with the simple observation that many of the most "successful" individuals in our society are more often than not highly vain, impetuous, individuals willing to take great chances under favorable circumstances, and yet the same genes land their owners in highly disproportionate numbers in prison or condemn to an early death. What is the difference? Is it simply fortuitous? The studies, whether animal or man, seem to suggest that the biggest operative influence as to whether the roll comes out snake eyes or box cars is mom and early nurturance.

Even more mindbending is that these polymorphic genes exist in two primate species--the rhesus monkey and man--the only two primate species that are not to be relegated to a narrow and comfortable ecological niche. I would say that this adds up to a very powerful argument in favor of mom if she is able to tip the scales that take a debt ridden gene and make it advantagous is arguably the only reason we are not still huddled about a fire on the savannah--that is had we even mastered fire.

Intelligence IMHO is too narrowly defined as the ability to rapidly process certain types of info in particular ways. That Steven Haawking is a wunderkind is beyond doubt, can the same be said for a Donald Trump, Barbra Walters, or dare I say Sarah Palin? From an evolutionary perspective, the answer seems clear. I think this muddies the water horribly when talking about intelligence and how people come to possesses it as there is no clear way to measure it, as no where do I see it measure evolutionary fitness which must be considered the ultimate "intelligence."

Ok, I read the article. It is interesting and I don't dispute it. I am disputing your interpretation of it. It seems you drew the connection in response to this thread and added a couple more of your own connections and conclusions so that they'd fit into this discussion.

The article is about success. I found nothing in it that indicates that a "supermom" will change the personality or intelligence of child. Only that a "supermom" will "teach" the child how to turn their particular traits (traits that we don't generally associate with success) into successful traits.

In fact, the article goes on to make the point that they are rare orchids in a field of dandelions. They don't turn into dandelions because of the "supermoming". They remain orchids; nurtured, healthy orchids instead of wilted orchids.

On top of that, I don't see mention of a measurement later in life, when the subjects are adult. As new as the research is, have any of the subjects even had a chance to reach adulthood yet? I reiterate, the OP article is about the fully developed adult, the end result, years and years after they've had all kinds of ups and downs and their personalities have leveled out.

 

[Andy Resnick]

<snip>

On top of that, I don't see mention of a measurement later in life, when the subjects are adult. As new as the research is, have any of the subjects even had a chance to reach adulthood yet? I reiterate, the OP article is about the fully developed adult, the end result, years and years after they've had all kinds of ups and downs and their personalities have leveled out.

But that is an essential component of all biology/psychology: the current state of an organism is highly dependent on the details of the history of that organism. We gloss over that point in Physics all the time-the current state of a system is assumed to be independent (or weakly dependent, at best) of the past states of the system.

Trying to apply that simplification to biology is pure folly. Even clonal populations of cells have a huge range of responses to simple stimuli- the standard deviation is often as large as the mean.

 

[denverdoc]

Ok, I read the article. It is interesting and I don't dispute it. I am disputing your interpretation of it. It seems you drew the connection in response to this thread and added a couple more of your own connections and conclusions so that they'd fit into this discussion.

The article is about success. I found nothing in it that indicates that a "supermom" will change the personality or intelligence of child. Only that a "supermom" will "teach" the child how to turn their particular traits (traits that we don't generally associate with success) into successful traits.

In fact, the article goes on to make the point that they are rare orchids in a field of dandelions. They don't turn into dandelions because of the "supermoming". They remain orchids; nurtured, healthy orchids instead of wilted orchids.

On top of that, I don't see mention of a measurement later in life, when the subjects are adult. As new as the research is, have any of the subjects even had a chance to reach adulthood yet? I reiterate, the OP article is about the fully developed adult, the end result, years and years after they've had all kinds of ups and downs and their personalities have leveled out.

I found nothing in it that indicates that a "supermom" will change the personality or intelligence of child.

Well I guess this depends on whether you consider behavior a measure of personality: The article opened with a study that showed a small but measureable (and much lauded) effect on the level of acting out behaviors which were considered potentially deleterious by providing a few hours of for the lack of a better and less emotionally charged term "improved parenting".

You may be quite correct in your insertion that I'm adding somewhat to the text of the article with knowledge of the subject not explicitly mentioned. One common observation (and the subject of lots of papers) is that kids with ADHD, unless treated by whatever means" tend to have fairly predictable downward trajectories leading to mildly sociopathic behavior early in adolescence and all too often leading to drug addiction, increasing antisocial behavior, and all too often, long term adult incarceration.

I agree that the discovery of these genes is far too recent to have generated conclusive studies in human cohorts, but you have to agree that the rhesus monkey research is tantalizing--since they grow up at 4:1 rate, data are beginning to accumulate, but agreed it is always a leap when crossing species, however closely related.

I guess if I had a primary point is that the situation may be too complex to even begin to assign some ratio as to importance of influence. To wit, that the early interactions with mom from years 0 to 3 say,and have to go well enough to prepare for future development/socialization. This much seems obvious. What the article adds to the discussion in my mind is the robust but difficult to quantify feedback between genetic endowment and environment which is occurring in both directions at multiple levels. And that genetic failings in one environment become blessings in another. That much does seem clear--whether the kid has a preference for a certain color or type of music or scores 112 on an IQ test seem far less important than how successfully the kid navigates the world and applies/reigns in certain hardwired predilictions is more on point in understanding ourselves and how best to maximize human potential.

 

[Pythagorean]

But that is an essential component of all biology/psychology: the current state of an organism is highly dependent on the details of the history of that organism. We gloss over that point in Physics all the time-the current state of a system is assumed to be independent (or weakly dependent, at best) of the past states of the system.

Trying to apply that simplification to biology is pure folly. Even clonal populations of cells have a huge range of responses to simple stimuli- the standard deviation is often as large as the mean.

Well, I can't deny that I'm a product of my physics background. That's interesting that the deviation is as large as the mean in cell populations, though I myself couldn't draw any conclusions about psychology from that. I mean, doesn't the same thing occur in physics? A bunch of little particles are a stochastic system, but the object they come together to make can be analyzed in a very Newtonian fashion?

Since this (the 50-0-50 rule) was taught by a developmental psychologist (Paul Bloom) in the Yale introductory psychology course, I assumed that there were controls involved in the experiment that came to this conclusion, and he mentions a little bit about the research. I only later found the article in psychology today just for reference for posting it here.

Here's the open course sessions. If anyone wants to see the lecture for themselves, it's #13 iirc:

http://oyc.yale.edu/psychology/introduction-to-psychology/content/class-sessions