I have learned some things of late that have congealed in such a way, so as to leave me in a bit of an existential crisis. One of my most precious beliefs, specifically, the importance of parenting style, as it pertains to child intelligence and personality outcomes, has been relegated to the proverbial dust heap alongside the id, the wandering uterus, and the Oedipus complex.


Why would the salience of parenting style even come into question? It seems ridiculous to pose such a question. Of course parenting style matters! It is widely believed that parents can and do shape and mold their youngsters in a meaningful way that plays out in the formation of an adult. But, and this is a big but, the reality is that the impact of what you do as a parent has a much narrower impact than you might think.


I discussed this last week in my post Ten Best Parenting Tips: But Does it Really Matter? where I shared the Parent’s Ten (Epstein, 2010) and laid out a question of the quality of the research used to delineate these ten great tips. In that post I noted that:


“We are lead to believe, based on the results of [the Epstein study], that we, as parents, can shape our children, and thus by engaging in The Parent’s Ten, produce happier, healthier, and wiser children. But can we really? Is there an illusion of cause here? Are these simply correlations? The findings of behavioral genetics would suggest that this is an illusion – that these variables vary in predictable ways based on the influence of a third variable – genes.”


Genes are the sticking point. Epstein did not control for the effect of shared genes in this study. It is likely that children who have well functioning parents will be likewise well functioning, not because of the parenting style employed by their parents, but because of their shared genes. Well functioning and happy adults breed happy and well functioning children. Ultimately, parenting style, seems to have little impact on such outcomes.


The current research from behavioral genetics provides a preponderance of evidence leading to the same conclusion: that the home environment, as it is influenced by parents, accounts for 0 to 10% of the variance in the personality and intelligence outcomes of children! Heredity (genes) accounts for about 50%. A long standing question about the remainder has ultimately pointed in the direction of the child’s peer group whereby they account for 40-50% of the variance on personality and intelligence outcomes (Pinker, 2002). As it turns out, peers are the nurture influence in the nature and nurture interplay.


This latter notion runs counter to nearly everything we have been taught regarding human development over the last 100 years (Gladwell, 1998). Freud first put parents at the core of the child’s personality and neurosis development, and there they have remained. Mothers in particular have fielded more than their share of blame with regard to the pathology of their offspring. Cold maternal parenting style, after all, had been blamed for autism. And perfection seeking mothers have been blamed for the development of anorexia in their teenage daughters. We know that these relationships are unfounded. Regardless, the thinking persists, and bad outcomes are attributed to bad parenting whereas good outcomes are the fruit of sound parenting. The problem with this type of thinking is that the research has not born it out.


The Minnesota studies of twins and the Colorado Adoption Project have made it clear (Harris, 1998): parents contribute their genes and that seems to be it. When it comes to personality variables such as openness to experience, conscientiousness, extroversion-introversion, antagonism-agreeableness, and neuroticism, parents affect this only through heritability. Factors like IQ, language proficiency, religiosity, nicotine dependence, hours of television watching, and political conservatism/liberalism are all hugely influenced by genes (Pinker, 2002).


How do we know this? Adopted children resemble their biological parents not their adoptive parents (Gladwell, 1998). Also, as Steven Pinker (2002) points out, “Identical twins reared apart are highly similar; identical twins reared together are more similar than fraternal twins reared together; biological siblings are far more similar than adoptive siblings. All this translates into substantial heritability values…”


And consider smoking. Who can forget the TV ad portraying a child watching and pondering the emulation of his father’s smoking behavior. The slogan was something akin to “like father like son.” They had it right, but the smoking behavior in front of the child was not the culprit. Children of smokers are two times more likely to smoke as children of non-smokers. What we see is that nicotine addiction is heavily influenced by genes. Adoptive children of smokers do not have elevated rates of smoking, and this greatly diminishes the role that modeling plays in the equation.


The psychologist Eric Turkheimer pulled together the unusually robust evidence from extensive studies of twins (fraternal and identical) reared together and apart as well as studies of adopted children relative to biological children and concluded that there are three important laws that help explain the development of personality characteristics and intelligence.  Steven Pinker suggests that these laws constitute the most important discovery in the history of psychology (2002). The three laws are as follows:


  1. All Human traits are heritable;
  2. The effect of being raised in the same family is smaller than the effect of the genes; and
  3. A substantial portion of the variation in complex human behavioral traits is not accounted for by the effects of genes or families.


So does this mean that what we do as parents doesn’t really matter? And does it mean that my role as a child psychologist helping parents manage very difficult children is a waste of time? This is my crisis.


Well … it does matter! How a parent treats and manages a child within the home will affect how the child behaves in the home and how the child feels about the parent. These are important issues. If poor parenting results in difficult feelings for the parent, “these feelings can last a lifetime – but they don’t necessarily cross over into the life the child leads outside the home” (Harris quoted in Gladwell, 1998).  Here is the important point “whatever our parents do to us is overshadowed, in the long run, by what our peers do to us” (Harris quoted in Gladwell, 1998). The home environment is very important for all involved – and parenting style can greatly impact that environment. So parenting style does matter – if only for the establishment of sanity in the home.  It seems to me that treating a child well is an ethical obligation. But if that’s not enough encouragement for treating another human being well, perhaps you should do so, in hopes that when you are old and frail, your children may treat you well (Harris paraphrased in Gladwell, 1998).


Pinker (2002) adds an important provision:


Differences among homes don’t matter within the samples of homes netted by these studies, which tend to be more middle-class than the population as a whole. But differences between those samples and other kinds of homes could matter. The studies exclude cases of criminal neglect, physical and sexual abuse, and abandonment in a bleak orphanage, so they do not show that extreme cases fail to leave scars. Nor can they say anything about the differences between cultures… In general, if a sample comes from a restricted range of homes, it may underestimate effects of homes across a wider range.


We do know that parenting style can have adverse consequences when a child is subjected to neglect or abuse.  This is hugely important!  Its not that parenting style doesn’t matter.  It matters greatly!  Parents can establish a happy encouraging environment, provide for the development of essential skills and knowledge; BUT, again, over the long term, it seems that these contributions do not shape the personality or intelligence of their children.  Their gene’s are responsible for their contributions.  What seems to be more important, when it comes to shaping the genetic contribution, is where a parent raises their child. It’s the peer group that finishes the job. Now that is scary! And I thought my crisis was over.




Epstein, R. (2010). What Makes a Good Parent? Scientific American MIND. November/December 2010. (pgs 46-51).


Gladwell, M. (1998).  Do Parents Matter? Judith Rich Harris and Child Development. Annals of Behavior. The New Yorker.


Lehrer, J. (2009). Do Parents Matter? Scientific American. April 9, 87http://www.scientificamerican.com/article.cfm?id=parents-peers-children


Pinker, S. (2002).  The Blank Slate: The Modern Denial of Human Nature. New York: Penguin Books.

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What makes a good parent?  Really?  What can we do to ensure that our children grow up happy, healthy and wise?  There is a lot of advice out there – some of which, on the surface seems quite sage.  But history is replete with really bad advice – some based in moral authority and some in the ill formed wisdom of so called experts.  New advice is commonplace and how often have you been confused by the contradictory nature of yesterday’s and today’s tips?  There are enough schools of thought out there to confirm and satisfy almost any advocate of any “reasonably sane” parenting approach and even some not so prudent approaches.  There is a pretty good reason for this variability and I’ll get to that in a minute, but first, lets look at a recent article from Scientific American MIND that provides a summary of a scientific analysis resulting in a list of the top ten most effective child rearing practices.


In What Makes a Good Parent? the author, Robert Epstein, shares the results of a study on parenting skills that he carried out at UC San Diego, with a student (Shannon Fox).  The results were presented at the annual convention of the American Psychological Association this past summer.  Epstein and Fox looked at parenting techniques advised by experts, strategies commonly employed by parents, and strategies that seemingly had efficacy in the real world.  They collected their data online from nearly 2000 parents who volunteered to take a test of parenting skills at Epstein’s website: http://MyParentingSkills.com.  The test was devised by Epstein based on the literature, whereby ten parenting techniques that had robust evidence with regard to good outcomes were selected and measured.   Epstein had the 10 skills assessed by 11 parenting experts to further evaluate their validity.    The participants answered 100 questions pertaining to their agreement (on a 5 point agree to disagree scale) with the ten parenting variables (e.g., “I generally encourage my child to make his or her own choices,” “I try to involve my child in healthful outdoor activities,” “No matter how busy I am, I try to spend quality time with my child.”).   In addition to these questions the test asked questions pertaining to important variables such as income and educational levels of the parents, marital status, parenting experience, age, as well as questions regarding the happiness, health and functioning capacity of their child/ren.


The results, coined by the author as The Parent’s Ten, make perfect sense to me as a parent of three reasonably well adjusted, happy and successful college students.  They also gel with my exposure to the literature and my experiences guiding parents within my professional capacity as a child psychologist over the last 16 years. Here is an excerpt from the article:


Here are 10 competencies that predict good parenting outcomes, listed roughly in order from most to least important. The skills – all derived from published studies – were ranked based on how well they predict a strong parent-child bond and children’s happiness, health and success.


  1. Love and affection. You support and accept the child, are physically affectionate, and spend quality one-on-one time together.
  2. Stress management. You take steps to reduce stress for yourself and your child, practice relaxations techniques and promote positive interpretations of events.
  3. Relationship skills. You maintain a healthy relationship with your spouse, significant other or co-parent and model effective relationship skills with other people.
  4. Autonomy and independence. You treat your child with respect and encourage him or her to become self-sufficient and self-reliant.
  5. Education and learning. You promote and model learning and provide educational opportunities for your child.
  6. Life skills. You provide for your child, have a steady income and plan for the future.
  7. Behavior Management. You make extensive use of positive reinforcement and punish only after other methods of managing behavior have failed.
  8. Health. You model a healthy lifestyle and good habits, such as regular exercise and proper nutrition, for your child.
  9. Religion. You support spiritual or religious development and participate in spiritual or religious activities.
  10. Safety. You take precautions to protect your child and maintain awareness of the child’s activities and friends.


Although you may not find these results all that surprising, Epstein suggests that they are because if you look closely at the list you’ll see that the vast majority of the skills are parental personality and/or life skill issues.  As this study suggests, a child’s well-being, it seems, is most closely associated with how a parent treats oneself (e.g., manages stress and maintains a healthy diet and exercise regimen), how one gets along with the co-parent (e.g., maintains and models important healthy relationships), as well as the efficacy of one’s life skills (e.g., sustains income and plans for the future), and how deeply one values education.


These “skills” constitute a full 50% of the list and when weighted, based on the degree of association, likely account for a huge and disproportionate amount of the influence on child happiness, health, and adaptive functioning outcomes.  And several of the other “skills” (e.g., affection, respect for the dignity of children, degree of parental control imposed, and even level of spirituality) really are behaviors that are known to vary associated with one other crucial, yet unmentioned variable.


You see, the presumption here is that children are brought into the world as malleable blank slates that we can mold through the type of parenting we employ.  The reality is that parents who employ these skills likely do so as a function of their intelligence and personality, which are heavily influenced by their genes.  The truth of the matter is likely that children whose parents care for themselves, have good social skills, and plan for the future will have happier, healthier, and wiser children, but not because of the parenting skills employed during their upbringing, but because of their shared genes.  Epstein did not control for the effect of shared genes in this study.  And neither have most of the researchers looking at the relationship between parenting behavior and children outcomes (Pinker, 2002).  The current research from behavioral genetics suggests that the home environment, as it is influenced by parents, accounts for 0 to 10% of the variance in the wellness outcomes of children!  Heredity accounts for about 50% and the child’s peer group accounts for the remainder (40-50%) (Pinker, 2002).


Epstein asks what parental characteristics are associated with good outcomes and finds that women produce only slightly better outcomes than men.  Likewise they found that married individuals produce slightly happier children than divorced parents.  Gay individuals actually report slightly happier children than do straight individuals.  And no differences were noted associated with race or ethnicity, but more educated individuals had the best outcomes.  He notes that “Some people just seem to have a knack for parenting, which cannot be easily described in terms of specific skills.”  He’s got that right!  That knack, although unacknowledged by Epstein, is largely a function of one’s genes.  Temperament is a personality trait that we know is hugely influenced by genes and Epstein notes that “Keeping calm is probably step one in good parenting.”


So we have another conundrum.  We are lead to believe, based on the results of this study, that we, as parents, can shape our children, and thus by engaging in The Parent’s Ten,  produce happier, healthier, and wiser children.  But can we really?  Is there an illusion of cause here?  Are these simply correlations?  The findings of behavioral genetics would suggest that this is an illusion – that these variables vary in predictable ways based on the influence of a third variable – genes.


Next week I’ll delve into this notion of whether how one parents really matters.  This exploration comes with significant discomfort for me as I am a behavioral child psychologist with 11 years of training and 16 years of practice steeped in the belief that I can help parents make a difference in the lives of their children.  I have long accepted the notion that the nature-nurture debate is not an either-or issue.  I see in my life and practice that outcomes are clearly the result of the influences of both nature and nurture.  Regardless, I have held the notion that it is parenting to a large extent, that accounts for a large portion of the nurturing influence.  Now I have to look carefully at the evidence, be willing to shed the ideological notion that we are blank slates, and accept the reality of the situation, no matter how hard and contrary to my beliefs.  This necessitates true intellectual honesty and deep scientific scrutiny.




Epstein, R. (2010). What Makes a Good Parent? Scientific American MIND. November/December 2010. (pgs 46-51).


Pinker, S. (2002).  The Blank Slate: The Modern Denial of Human Nature. New York: Penguin Books.


My wife and I recently spent some time in New York City and one of our traditions is to take in a Broadway show. This time we stepped a bit off-Broadway to see the bawdy but Tony Award Winning Avenue Q. On the surface, this show seems silly, but it actually addresses some important issues. Essentially it is about the “coming of age” of young adults stepping out into the real world. The way the show is played out is interesting in that it employs a mixture of human actors, human puppets, and monster puppets – with all puppeteers fully visible on stage. As is often the case in theater, It necessitated suspension of reality and letting go of conventional thinking.


The play itself satirized the longstanding PBS children’s show Sesame Street both in format and message. Make no mistake however, this is not a show for children, or even for folks put-off by lewd language or sexual situations. Regardless, it delves headlong into issues that challenge the teachings of Sesame Street, laying bare the notion that everyone is “special.”


I couldn’t help but hearken back to a post I wrote entitled Self Esteem on a Silver Platter, that highlights the cost of telling children they are smart. I wonder if there are similar costs to telling children they are inherently special? Obviously, the writers of Ave. Q had the same question in mind.


As Princeton, the play’s protagonist, struggled with the reality of entering the world of work and his internalized notion of his own specialness, I thought about my college age children and my own experience when I left a small town to attend college. I have to believe that my experience was not unlike Princeton’s and I’m guessing, is very similar to my children’s experiences, as they make the transition from “Big fish in a small pond – to small fish in a big pond.” It’s a humbling transition.


Some of the other issues confronted by the cast and characters include racism and homophobia. Each of these prejudices are attitudes played out in a large part by our intuitive brains. That is not to say that we are powerless over them – we can change these deep seated attributes through concerted effort and appropriate exposure. But it begs the question: “Where do these prejudices come from?” I believe the consensus is clear, prejudices are learned from, and taught by those important people around us who model and mold us throughout childhood. It is also important to understand that there seems to be a natural inclination within us to be suspicious of those who are different from us. This tribal tendency to classify outsiders as threats may stem back to our ancestral roots when outsiders were indeed threats to our very survival: and this successful propensity has carried on due to natural selection. It seems that there is a human inclination to be prejudiced. Compound that inclination with other human brain failings (e.g., confirmation bias), and minimal exposure to diversity, as well as influential bigots, and you have a near certain prejudicial clone. To make matters worse, all you have to do is turn on the TV and watch the news to feed those prejudices. Racism in our culture is not very subtle. But I digress.


The point that I am trying to make is that we all have biases, and that they are intuitive to a degree. Next week I am going to explore the Implicit Associations Test and its implications that support the notion that stereotypes or prejudices are indeed deeply rooted in our intuition. If you have not taken the Implicit Associations Test, do so, particularly the Race Test. You may be surprised by the results. I know I was. This is in fact, one of the sub-plots in Ave. Q – we are all a bit racist, and perhaps a bit homophobic too; although, I will argue to my grave that I do not value people differently based on their race, gender, or sexual orientation.


Ave. Q also deals with schadenfreude, which is the pleasure we gain from other’s pain or struggles. This is a curious proclivity, one I hope to gain a better understanding of. As I think back to childhood, I can recall experiencing a strong compulsion to laugh when a friend was injured through our mutual play. I remember knowing that this was somehow wrong and inappropriate, regardless, there was this deep urge to chuckle. Looking back, I know that it was not a rational response – it was intuitive. The reality is that most of us are at least relieved by the misery of others and we often gain some appreciation that our lives are not so bad after all. The play’s treatment of this very issue normalizes the experience and perhaps explains our societal infatuation with gossip. In my profession, on a daily basis, I see real agony in the lives of the families I work with, and thus find gossip repulsive.


One of the major goals of art is to incite thought, and Ave. Q effectively pulled this off. I’d like to say that I have no prejudices, but Ave. Q and the results of my IAT suggest that this may not be absolutely true. In reference to the work of Christopher Chabris and Daniel Simons in their book entitled The Invisible Gorilla, I wonder if perhaps there is an Illusion of an Open Mind? I shall not rest comfortably with this illusion, and I am fully committed to overcoming the failings of my naturally selected and intuitive tendencies. The first step is accepting this reality.


There are many well intentioned folks out there who believe that childhood vaccinations cause Autism. Last week I covered the origins of this belief system as well as its subsequent debunking in Vaccines and Autism. Despite the conclusive data that clearly establishes no causal link between vaccines and Autism, the belief lives on. Why is this? Why do smart people fall prey to such illusions? Chabris and Simons contend in their book, The Invisible Gorilla, that we fall prey to such myths because of the Illusion of Cause. Michael Shermer (2000), in his book, How We Believe, eloquently describes our brains as a Belief Engine. Underlying this apt metaphor is the notion that “Humans evolved to be skilled pattern seeking creatures. Those who were best at finding patterns (standing upwind of game animals is bad for the hunt, cow manure is good for the crops) left behind the most offspring. We are their descendants.” (Shermer, p. 38). Chabris and Simons note that this refined ability “serves us well, enabling us to draw conclusions in seconds (or milliseconds) that would take minutes or hours if we had to rely on laborious logical calculations.” (p. 154). However, it is important to understand that we are all prone to drawing erroneous connections between stimuli in the environment and notable outcomes. Shermer further contends that “The problem in seeking and finding patterns is knowing which ones are meaningful and which ones are not.


From an evolutionary perspective, we have thrived in part, as a result of our tendency to infer cause or agency regardless of the reality of threat. For example, those who assumed that rustling in the bushes was a tiger (when it was just wind) were more likely to take precautions and thus less likely, in general, to succumb to predation. Those who were inclined to ignore such stimuli were more likely to later get eaten when in fact the rustling was a hungry predator. Clearly from a survival perspective, it is best to infer agency and run away rather than become lunch meat. The problem that Shermer refers to regarding this system is that we are subsequently inclined toward mystical and superstitious beliefs: giving agency to unworthy stimuli or drawing causal connections that do not exist. Dr. Steven Novella, a neurologist, in his blog post entitled Hyperactive Agency Detection notes that humans vary in the degree to which they assign agency. Some of us have Hyperactive Agency Detection Devices (HADD) and as such, are more prone to superstitious thinking, conspiratorial thinking, and more mystical thinking. It is important to understand as Shermer (2000) makes clear:


“The Belief Engine is real. It is normal. It is in all of us. Stuart Vyse [a research psychologist] shows for example, that superstition is not a form of psychopathology or abnormal behavior; it is not limited to traditional cultures; it is not restricted to race, religion, or nationality; nor is it only a product of people of low intelligence or lacking education. …all humans possess it because it is part of our nature, built into our neuronal mainframe.” (p. 47).


We all are inclined to detect patterns where there are none. Shermer refers to this tendency as patternicity. It is also called pareidolia. I’ve previously discussed this innate tendency noting that “Our brains do not tolerate vague or obscure stimuli very well. We have an innate tendency to perceive clear and distinct images within such extemporaneous stimuli.” It is precisely what leads us to see familiar and improbable shapes in puffy cumulus clouds or the Virgin Mary in a toasted cheese sandwich. Although this tendency can be fun, it can also lead to faulty and sometimes dangerous conclusions. And what is even worse is that when we hold a belief, we are even more prone to perceive patterns that are consistent with or confirm that belief. We are all prone to Confirmation Bias – an inclination to take in, and accept as true, information that supports our belief systems and miss, ignore, or discount information that runs contrary to our beliefs.


Patternicity and confirmation bias alone are not the only factors that contribute to the illusion of cause. There are at least two other equally salient intuitive inclinations that lead us astray. First, we tend to infer causation based on correlation. And second, the appeal of chronology, or the coincidence of timing, also leads us toward drawing such causal connections (Chabris & Simons, 2010).


A fundamental rule in science and statistics is that correlation does not infer causation. Just because two events occur in close temporal proximity, does not mean that one leads to the other. Chabris and Simons note that this rule is in place because our brains automatically – intuitively – draw causal associations, without any rational thought. We know that causation leads to correlation – but it is erroneous to assume that the opposite is true. Just because A and B occur together does not mean A causes B or vice-versa. There may be a third factor, C, that is responsible for both A and B. Chabris and Simons use ice cream consumption and drownings as an example. There is a sizable positive correlation between these two variables (as ice cream consumption goes up so do the incidences of drowning), but it would be silly to assume that ice cream consumption causes drowning, or that increases in the number of drownings causes increases in ice cream consumption. Obviously, a third factor, summer heat, leads to both more ice cream consumption and more swimming. With more swimming behavior there are more incidents of drowning.


Likewise, with vaccines and Autism, although there may be a correlation between the two (increases in the number of children vaccinated and increases in the number of Autism diagnoses), it is incidental, simply a coincidental relationship. But given our proclivity to draw inferences based on correlation, it is easy to see why people would be mislead by this relationship.


Add to this the chronology of the provision of the MMR vaccine (recommended between 12 and 18 months), and the typical time at which the most prevalent symptoms of Autism become evident (18-24 months), people are bound to infer causation. Given the fact that millions of children are vaccinated each year, there are bound to be examples of tight chronology.


So what is at work here are hyperactive agency detection (or overzealous patternicity), an inherent disposition to infer causality from correlation, and a propensity to “interpret events that happened earlier as the causes of events that happened or appeared to happen later” (Chabris & Simons, 2010, p. 184).  Additionally, you have a doctor like Andrew Wakefield misrepresenting data in such a way to solidify plausibility and celebrities like Jenny McCarthy using powerful anecdotes to convince others of the perceived link. And anecdotes are powerful indeed. “..[W]e naturally generalize from one example to the population as a whole, and our memories for such inferences are inherently sticky. Individual examples lodge in our minds, but statistics and averages do not. And it makes sense that anecdotes are compelling to us. Our brains evolved under conditions in which the only evidence available to us was what we experienced ourselves and what we heard from trusted others. Our ancestors lacked access to huge data sets, statistics, and experimental methods. By necessity, we learned from specific examples…” (Chabris & Simons, 2010, pp. 177-178).  When an emotional mother (Jenny McCarthy) is given a very popular stage (The Oprah Winfrey Show) and tells a compelling story, people buy it – intuitively – regardless of the veracity of the story. And when we empathize with others, particularly those in pain, we tend to become even less critical of the message conveyed (Chabris & Simons, 2010). These authors add that “Even in the face of overwhelming scientific evidence and statistics culled from studies of hundreds of thousands of people, that one personalized case carries undue influence” (p.178).


Although the efficacy of science is unquestionable, in terms of answering questions like the veracity of the relationship between vaccines and Autism, it appears that many people are incapable of accepting the reality of scientific inquiry (Chabris & Simons, 2010). Acceptance necessitates the arduous application of reason and the rejection of the influences rendered by the intuitive portion of our brain. This is harder than one might think. Again, it comes down to evolution. Although the ability to infer cause is a relatively recent development, we hominids are actually pretty good at it. And perhaps, in cases such as this one, we are too proficient for our own good (Chabris & Simons, 2010).




Center for Disease Control. (2009). Recommended Immunization Schedule for Persons Aged 0 Through 6 Years. http://www.cdc.gov/vaccines/recs/schedules/downloads/child/2009/09_0-6yrs_schedule_pr.pdf


Chabris, C. F., & Simons, D. J. (2010). The Invisible Gorilla. Random House: New York.


Novella, S. (2010). Hyperactive Agency Detection. NeuroLogica Blog. http://www.theness.com/neurologicablog/?p=1762


Shermer, M. (2000). How We Believe. W.H. Freeman / Henry Holt and Company: New York.


Vaccines and Autism

13 August 2010

It is hard to imagine anything more precious than one’s newborn child. Part of the joy of raising a child is the corresponding hope one has for the future. Don’t we all wish for our children a life less fraught with the angst and struggles we ourselves endured? One of the less pleasant aspects of my job has the effect, at least temporarily, of robbing parents of that hope. This erosion occurs in the parent’s mind and heart as a consequence of a diagnosis I often have to provide. I am a psychologist employed in part to provide diagnostic evaluations of preschool age children suspected of having Autism. My intention is never to crush hope, instead it is to get the child on the right therapeutic path as early as possible in order to sustain as much hope as possible. However, uttering the word AUTISM in reference to one’s child constitutes a serious and devastating emotional blow.


Many parents come to my office very aware of their child’s challenges and the subsequent implications. They love their child, accept him as he is, and just want to do whatever they can to make his life better. Others come still steeped in hope that their child’s challenges are just a phase or believing that she is just fine. Regardless, most of them report that they suspected difficulties very early in the child’s development. For example, many note a lack of smiles, chronic agitation and difficulty soothing their child. Some children had not been calmed by being held or may have even resisted it. Some other children I see develop quite typically. They smile, giggle, rejoice at being held, coo and babble, and ultimately start to use a few words with communicative intent. The parents of this latter and rather rare subset, then watch in dismay as their child withdraws, often losing both functional communication and interest in other children.


The timing of this developmental back-slide most often occurs at around 18 months of age. This regression happens to coincide with the recommended timing of the provision of the Measles-Mumps-Rubella (MMR) vaccine. This temporal chronology is important as it has lead, in part, to a belief that the vaccine itself is responsible for the development of Autism. What these parents must experience at this time, I can only imagine, is a horrible combination of confusion and grief. They have had their hopes encouraged and reinforced only to have them vanquished. And it is human nature, under such circumstances, to look for a direct cause. It makes perfect sense that parents would, given the chronicity of events in some cases, suspect the MMR vaccine as the cause of their child’s regression.


During my occasional community talks on Autism, I often am asked about the alleged connection between vaccines and Autism. The coincidental temporal relationship between the provision of the MMR vaccine and this developmental decay leads to what Chabris and Simons in The Invisible Gorilla refer to as the Illusion of Cause. Chabris and Simons discuss how “chronologies or mere sequences of happenings” lead to the inference “that earlier events must have caused the later ones.” (2010, p. 165). By default, as a result of evolution, our brains automatically infer causal explanations based on temporal associations (Chabris & Simons, 2010).


At nearly every talk I give, there is someone in the audience who is convinced that their child (or a relative) is a victim of the MMR vaccine. Their compelling anecdotes are very difficult to refute or discuss. I find that the application of reason, or data, or both, misses the mark and comes off as being cold and insensitive.


For such causal relationships to endure and spread they often need some confirmation of the effect by an “expert.” This is where the story of Dr. Andrew Wakefield comes into play. Wakefield, a GI Surgeon from the UK published a paper in the prestigious UK medical journal, The Lancet, alleging a relationship between the MMR vaccine and the development of Autism. His “expert” opinion offered legitimacy to already brewing suspicions backed by the perceived correlates of increases in both vaccination and Autism rates, as well as the apparent chronology between the timing of the vaccines and the onset of Autism. Wakefield provided credibility and sufficient plausibility: and as a result, the news of the alleged relationship gained traction.


But hold on! There were major flaws with Wakefield’s study that were not initially detected by The Lancet’s peer review panel. First of all, Wakefield was hired and funded by a personal injury attorney who commissioned him to prove that the MMR vaccine had harmed his clients (caused Autism). His study was not designed to test a hypothesis: it was carried out with the specific objective of positively establishing a link between Autism and provision of the MMR vaccine. From the outset the study was a ruse, disguised as science.


Just this year (2010), 12 years after the initial publication of Wakefield’s infamous study, The Lancet retracted it and Dr. Wakefield has been stripped of his privilege to practice medicine in the UK. Problems however, surfaced years ago: as early as 2004, when 10 of 13 co-authors retracted their support of a causal link. In 2005 it was alleged that Wakefield had fabricated data – in fact, some of the afflicted children used to establish the causal link had never actually received the MMR vaccine!


Since the initial publication of this study, hundreds of millions of dollars have been spent investigating the purported relationship between vaccines and Autism. Despite extensive large scale epidemiological studies, there have been no replications of Wakefield’s findings. Children who had not been vaccinated developed Autism at the same rate as those who had received the MMR. There is no relationship between the MMR vaccine and the development of Autism. As a result of Wakefield’s greed, hundreds of millions of dollars have been wasted. Those dollars could have been devoted to more legitimate pursuits, and that is not the worst of it. I will get to the real costs in a bit.


Another aspect of the history of this controversy is associated with the use of thimerosal as a preservative in vaccines. This notion, which has also been debunked, gained plausibility because thimerosal contains mercury, a known neurotoxin. You may ask: “Why on earth would a neurotoxin be used in vaccines?” Researchers have clearly established that thimerosal poses no credible threat to humans at the dosage levels used in vaccines. However, given the perceived threat, Thimerosal is no longer used as a preservative in routine childhood vaccinations. In fact, the last doses using this preservative were produced in 1999 and expired in 2001. Regardless, the prevalence of autism seems to be rising.


It is important to understand that mercury can and does adversely affect neurological development and functioning. However, long term exposure at substantially higher doses than present in thimerosal are necessary for such impact. The mercury in thimerosal is ethyl-mercury, which is not fat-soluble. Unlike the fat-soluble form of methyl-mercury (industrial mercury), ethyl-mercury is flushed from the body very quickly. Methyl-mercury can be readily absorbed into fatty brain tissue and render its damage through protracted contact. Methyl-mercury works its way into the food chain and poses a hazard to us if we eat too much fish (particularly those at the high end of the food chain). In reality, one is at more risk from eating too much seafood (shark and tuna) than from getting an injection of a vaccine preserved with thimerosal. Yet there does not seem to be a movement to implicate seafood as the cause of Autism.


Even though the relationship between vaccines and Autism has been thoroughly debunked, there is a movement afoot, steeped in conspiratorial thinking, that alleges that “Big Pharmacy” and the “Government” are colluding to deceive the people and that elaborately fabricated data is used to cover up a relationship. This belief lives on. How can this be so? Even intelligent and well educated people I know are avoiding important childhood immunizations based on the fear and misinformation spread by these well intentioned people.


In 2003, in the UK, the MMR vaccine rate had fallen to below 79% whereas a 95% rate is necessary to maintain herd immunity. Currently, the vaccine rates are dropping in the US due to the efforts of celebrities like Jenny McCarthy who purports that her son’s Autism was caused by vaccines. McCarthy campaigns fiercely against childhood immunizations spurred on by the likes of Oprah Winfrey. Even folks like John McCain, Joe Lieberman, and Robert F. Kennedy, Jr have spread such misinformation. Continuing to contend that the MMR vaccine is the culprit, Wakefield has moved to the US and has risen to martyr status among the anti-vaccine folk. You need to know that just months before he published his seminal paper, Wakefield received a patent on a Measles Vaccine that he alleges, “cures” Autism. He has much to gain financially, in his attempt to scare people away from the current safe and effective MMR vaccine.


It amazes me that people do not automatically dismiss this alleged vaccine-Autism link. Wakefield’s conflict of interest and discredited research practices alone draw into question anything he has to say. The mountains of epidemiological evidence also favors rejection of a causal relationship between the MMR vaccine and Autism. However, the power of anecdotes and misguided beliefs place millions of children in harm’s way.


Imagine yourself as a parent of a child who cannot get the MMR vaccine because of a serious medical condition (e.g., cancer). Such vulnerable children, of which there are millions worldwide, depend on herd immunity for their very survival. Now imagine that your child is inadvertently exposed to measles by coming into contact with a child who wasn’t vaccinated (because of misguided parental fear). Because your child’s compromised immunity, she develops the measles and gets seriously ill or dies. Such a scenario, although improbable is not impossible. It is more likely today largely due to the diminished herd immunity caused by misinformation. Whooping Cough (Pertussis) is likewise posing serious concerns (and one documented death) in unvaccinated clusters because of the anti-vaccine folk. This myth persists, in part, because of the Illusion of Cause, and the consequences have become deadly. Next week I will delve into this Illusion that sustains this erroneous and dangerous belief system.




Association for Science in Autism Treatment. (2009).  Autism & Vaccines: The Evidence to Date. Vol. 6., No. 1 http://www.asatonline.org/pdf/summer2009.pdf


Center for Disease Control. Autism Spectrum Disorders: Data & Statistics. http://www.cdc.gov/ncbddd/autism/data.html


Chabris, C. F., & Simons, D. J. (2010).  The Invisible Gorilla. Random House: New York.


Plait, P. (2010). The Australian antivax movement takes its toll. Bad Astronomy Blog. http://blogs.discovermagazine.com/badastronomy/2009/04/26/the-australian-antivax-movement-takes-its-toll/


Recently, Fox News, aired a story posing the question as to whether Fred Rogers was evil.  Why you may ask, would anyone use the word evil in reference to such a gentle man?  They were suggesting that his you’re special message fostered unworthy self esteem and in effect ruined an entire generation of children.  This accusation inspired a fair amount of discourse that in some cases boiled down to the question of why children today have such hollow needy shells.  An example of the discourse on this topic can be seen at Bruce Hood’s blog in an article entitled Mr. Rogers is Evil According to Fox News.


The consensus among skeptics was that Mr. Rogers was not, in fact, evil and that he is not responsible for the current juvenile generation’s need for much praise and attention for relatively meaningless contribution. There was almost universal acknowledgment of the problem however, and discussions lead to troubling issues such as grade inflation at schools and universities and poor performance in the workplace. In an intriguing article by Carol Mithers in the Ladies Home Journal entitled Work Place Wars addresses the workplace implications of this phenomena. Mithers notes:

“.…. the Millennials — at a whopping 83 million, the biggest generation of all…. are technokids, glued to their cell phones, laptops, and iPods. They’ve grown up in a world with few boundaries and think nothing of forming virtual friendships through the Internet or disclosing intimate details about themselves on social networking sites. And, many critics charge, they’ve been so coddled and overpraised by hovering parents that they enter the job market convinced of their own importance. Crane calls them the T-ball Generation for the childhood sport where “no one fails, everyone on the team’s assured a hit, and every kid gets a trophy, just for showing up.


Workers of this generation are known for their optimism and energy — but also their demands: “They want feedback, flexibility, fun, the chance to do meaningful work right away and a ‘customized’ career that allows them to slow down or speed up to match the different phases of life,” says Ron Alsop, author of The Trophy Kids Grow Up: How the Millennial Generation Is Shaking Up the Workplace.

I find it ironic that the very people today who struggle with the behavior of the Millennials are the ones who shaped the behaviors of concern. I personally have struggled with the rampant misapplication of praise, attention, and the provision of reinforcement for meaningless achievements. I have seen this everywhere – in homes, schools, youth athletic clubs, you name it. It has been the most recent parenting zeitgeist. But where did this philosophy come from?


Throughout my doctoral training in psychology (late 80’s and early 90’s) I learned that reinforcement is a powerful tool, but it was clear to me that it has to be applied following behaviors you WANT to increase. Nowhere in my studies did I read of the importance of raising children through the application of copious amounts of reinforcement just to bolster their self esteem. I am aware of no evidence based teachings that suggest this approach. However, given the near universal application of these practices it must of come from somewhere. This very question, I’m sure, lead to the placement of responsibility squarely on the shoulders of poor Mr. Rogers.


Although the source of this approach remains a mystery to me, Dr. Carol Dweck’s work clarifies the process of the outcome. In an interview in Highlights, Dr. Dweck discusses Developing a Growth Mindset.  Dr. Dweck has identified two basic mindsets that profoundly shape the thinking and behavior both we as adults exhibit and foster in our children.  She refers to these as the Fixed Mindset and the Growth Mindset. People with a Fixed Mindset, Dr. Dweck notes in the Highlights article, “believe that their achievements are based on innate abilities. As a result, they are reluctant to take on challenges.” Dweck further notes that “People with Growth Mindsets believe that they can learn, change, and develop needed skills.  They are better equipped to handle inevitable setbacks, and know that hard work can help them accomplish their goals.” In this same article “She suggests that we should think twice about praising kids for being “smart” or “talented,” since this may foster a Fixed Mindset. Instead, if we encourage our kids’ efforts, acknowledging their persistence and hard work, we will support their development of a Growth Mindset – better equipping them to learn, persist and pick themselves up when things don’t go their way.”


Dweck’s conclusions are based on extensive research that clearly supports this notion. Jonah Lehrer, in his powerful book, How We Decide discussed the relevance of Dweck’s most famous study. This work involved more than 400 fifth grade students in New York City, who were individually given a set of relatively simple non-verbal puzzles. Upon completing the puzzles the students were provided with one of two one-sentence praise statements. Half of the participants were praised for their innate intelligence (e.g., “You must be smart at this.”).  The other half were praised for their effort (e.g., “You must have worked really hard.”).


All participants were then given a choice between two subsequent tasks – one described as a more challenging set of puzzles (paired with the assurance that they would learn a lot from attempting) and a set of easier puzzles like the ones the subjects just completed.  In summarizing Dweck’s results, Lehrer noted “Of the group of kids that had been praised for their efforts, 90 percent chose the harder set of puzzles. However, of the kids that were praised for their intelligence , most went for the easier test.”  Dweck concludes that praise statements that focus on intelligence encourage risk avoidance. The “smart” children do not want to risk having their innate intelligence come under suspicion.  It is better to take the safe route and maintain the perception and feeling of being smart.


Dweck went on to demonstrate how this fear of failure can inhibit learning.  The same participants were then given a third set of puzzles that were intentionally very difficult in order to see how the children would respond to the challenge.   Those who were praised for their effort on the initial puzzles worked diligently on the very difficult puzzles and many of them remarked about how much they enjoyed the challenge. The children who were praised for their intelligence were easily discouraged and quickly gave up.  Their innate intelligence was challenged – perhaps they were not so smart after all.  Then all subjects were subjected to a final round of testing.  This set of puzzles had a degree of difficulty comparable to the first relatively simple set. Those participants praised for their effort showed marked improvements in their performance.  On average their scores improved by 30 percentage points.   Those who were praised for their intelligence, the very children who had just had their confidence shaken by the very difficult puzzles, on average scored 20 percentage points lower than they had on the first set.  Lehrer noted in reference to the participants praised for their effort that “Because these kids were willing to challenge themselves, even if it meant failing at first, they ended up performing at a much higher level.” With regard to the participants praised for intelligence Lehrer writes “The experience of failure had been so discouraging for the “smart” kids that they actually regressed.


In the Highlights interview Dweck suggests:

“It’s a mistake to think that when children are not challenged they feel unconditionally loved. When you give children easy tasks and praise them to the skies for their success, they come to think that your love and respect depend on their doing things quickly and easily. They become afraid to do hard things and make mistakes, lest they lose your love and respect. When children know you value challenges, effort, mistakes, and learning, they won’t worry about disappointing you if they don’t do something well right away.”

She further notes:

“The biggest surprise has been learning the extent of the problem—how fragile and frightened children and young adults are today (while often acting knowing and entitled). I watched as so many of our Winter Olympics athletes folded after a setback. Coaches have complained to me that many of their athletes can’t take constructive feedback without experiencing it as a blow to their self-esteem. I have read in the news, story after story, how young workers can hardly get through the day without constant praise and perhaps an award. I see in my own students the fear of participating in class and making a mistake or looking foolish. Parents and educators tried to give these kids self-esteem on a silver platter, but instead seem to have created a generation of very vulnerable people.”

So, we have an improved understanding of what has happened – but not necessarily of how the thinking that drives such parenting behavior came to be. Regardless, it is what it is, and all we can do is change our future behavior. Here are some cogent words of advice from Dr. Dweck (again from the Highlights article):

  1. “Parents can also show children that they value learning and improvement, not just quick, perfect performance. When children do something quickly and perfectly or get an easy A in school, parents should not tell the children how great they are. Otherwise, the children will equate being smart with quick and easy success, and they will become afraid of challenges. Parents should, whenever possible, show pleasure over their children’s learning and improvement.”
  2. Parents should not shield their children from challenges, mistakes, and struggles. Instead, parents should teach children to love challenges. They can say things like “This is hard. What fun!” or “This is too easy. It’s no fun.” They should teach their children to embrace mistakes, “Oooh, here’s an interesting mistake. What should we do next?” And they should teach them to love effort: “That was a fantastic struggle. You really stuck to it and made great progress” or “This will take a lot of effort—boy, will it be fun.
  3. Finally, parents must stop praising their children’s intelligence. My research has shown that, far from boosting children’s self-esteem, it makes them more fragile and can undermine their motivation and learning. Praising children’s intelligence puts them in a fixed mindset, makes them afraid of making mistakes, and makes them lose their confidence when something is hard for them. Instead, parents should praise the process—their children’s effort, strategy, perseverance, or improvement. Then the children will be willing to take on challenges and will know how to stick with things—even the hard ones.”




Dweck, C. Developing a Growth Mindset. Highlights Parents.com Interview  http://www.highlightsparents.com/parenting_perspectives/interview_with_dr_carol_dweckdeveloping_a_growth_mindset.html


Hood, B. Mr Rogers is Evil According to Fox Newshttp://brucemhood.wordpress.com/2010/05/03/mr-rogers-is-evil-according-to-fox-news/


Lehrer, J. 2009.  How We Decide. Houghton Mifflin Harcourt: New York.


Mithers, C. Workplace Wars. Ladies Home Journal. http://www.lhj.com/relationships/work/worklife-balance/generation-gaps-at-work/