60 seconds – Dr Leaf and Anxiety

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Dr Caroline Leaf, communication pathologist and self-titled cognitive neuroscientist, says that “A chaotic mind filled with rogue thoughts of anxiety and worry sends out the wrong signals and affects you right down to the level of your DNA!” She also says that “Toxic thinking destroys the brain!”

In other words:

Anxiety → Toxic thought → DNA changes +  Brain damage

But that’s not what science says. According to modern research, anxiety disorders are the result of a genetic predisposition to increased vulnerability to early life stress, and to chronic stress [1]. The other way of looking at it is that people who don’t suffer from anxiety disorders have a fully functional capacity for resilience [2,3].

In other words:

DNA changes + External stress → Anxiety

Dr Leaf’s teaching is backwards. Perhaps it’s time she turned it around.


[1] Duman EA, Canli T. Influence of life stress, 5-HTTLPR genotype, and SLC6A4 methylation on gene expression and stress response in healthy Caucasian males. Biol Mood Anxiety Disord 2015;5:2
[2] Wu G, Feder A, Cohen H, et al. Understanding resilience. Frontiers in behavioral neuroscience 2013;7:10
[3] Russo SJ, Murrough JW, Han M-H, Charney DS, Nestler EJ. Neurobiology of resilience. Nature neuroscience 2012 November;15(11):1475-84

Dr Leaf and Anxiety

Strong marketing can’t make up for weak ideas

Well Dr Leaf, 10 out of 10 for persistence.

Dr Caroline Leaf is a communication pathologist and a self-titled cognitive neuroscientist. In the last month or so, Dr Leaf has been hammering home her foundational belief that the mind is in control of the brain, and indeed, that your thoughts are the key to everything in life, a bit like 42 in “The Hitchhikers Guide to the Galaxy”. According to Dr Leaf, your thoughts are the answer to life, the universe, and everything.

Dr Leaf has attempted to prove her point through quotes from neuroscientists, from her own teaching, and from some published research. All she’s ended up proving is that she’s so desperate to prop up the concept that she’ll stoop to cherry-picking articles and massaging quotes. Poor form for a woman who promotes herself as a scientist.

Today’s meme is the spiritual justification of her position, expressed as a lovely little graphic with a verse from Proverbs 4:23. It’s a real Pinterest special. Most people would look at the pretty picture and accept the quote without question. It’s good marketing for sure.

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But if you strip back all of the eye-candy, is the meme still worth posting? Is Dr Leaf’s meme an accurate depiction of what Proverbs 4:23 truly means.

First things first, is the meme an accurate quote? In this case, it is. The Good News Bible really does say, “Be careful how you think; your life is shaped by your thoughts.” (https://www.biblegateway.com/passage/?search=Proverbs+4%3A23&version=GNT)

So the next question is, is the Good News version an accurate translation of the scripture? It’s interesting that nearly every other translation doesn’t mention thoughts and thinking at all:

New International Version = Above all else, guard your heart, for everything you do flows from it.
New Living Translation = Guard your heart above all else, for it determines the course of your life.
English Standard Version = Keep your heart with all vigilance, for from it flow the springs of life.
New American Standard Bible = Watch over your heart with all diligence, For from it flow the springs of life.
King James Bible = Keep thy heart with all diligence; for out of it are the issues of life.
Holman Christian Standard Bible = Guard your heart above all else, for it is the source of life.
International Standard Version = Above everything else guard your heart, because from it flow the springs of life.
NET Bible = Guard your heart with all vigilance, for from it are the sources of life.
Aramaic Bible in Plain English = Keep your heart with all caution because from it is the outgoing of life.
GOD’S WORD® Translation = Guard your heart more than anything else, because the source of your life flows from it.
JPS Tanakh 1917 = Above all that thou guardest keep thy heart; For out of it are the issues of life.
New American Standard 1977 = Watch over your heart with all diligence, For from it flow the springs of life.
Jubilee Bible 2000 = Above all else, guard thy heart; for out of it flows the issues of life.
King James 2000 Bible = Keep your heart with all diligence; for out of it are the issues of life.
American King James Version = Keep your heart with all diligence; for out of it are the issues of life.
American Standard Version = Keep thy heart with all diligence; For out of it are the issues of life.
Douay-Rheims Bible = With all watchfulness keep thy heart, because life issueth out from it.
Darby Bible Translation = Keep thy heart more than anything that is guarded; for out of it are the issues of life.
English Revised Version = Keep thy heart with all diligence; for out of it are the issues of life.
Webster’s Bible Translation = Keep thy heart with all diligence; for out of it are the issues of life.
World English Bible = Keep your heart with all diligence, for out of it is the wellspring of life.
Young’s Literal Translation = Above every charge keep thy heart, For out of it are the outgoings of life.

Nearly every other English translation refers to “the heart”. Obviously not the literal “heart”, that muscular blood pump in the middle of our chests, but the metaphoric heart, the human soul. So even on majority rules, the Good News Bible translation is looking shaky. Is there any further corroborating evidence to help us understand which version is the most correct?

The answer would be in the original Hebrew. The word for ‘heart’ in Proverbs 4:23 is לֵב (leb), and more broadly is a word relating to the soul, ‘inner man, mind, will, heart, understanding’ (https://www.blueletterbible.org/lang/lexicon/lexicon.cfm?Strongs=H3820&t=KJV). In some verses, the word in used in reference to what would be considered thoughts, but in many others, the word is used to describe a person’s feelings or motivations, or attitudes, or even specific intelligence and manual skills. For example:

Genesis 17:17: “Then Abraham fell upon his face, and laughed, and said in his heart, Shall a child be born unto him that is an hundred years old? and shall Sarah, that is ninety years old, bear?”
Genesis 42:28: “And he said unto his brethren, My money is restored; and, lo, it is even in my sack: and their heart failed them, and they were afraid, saying one to another, What is this that God hath done unto us?”
Exodus 8:32: “And Pharaoh hardened his heart at this time also, neither would he let the people go.”
Exodus 35:35: “Them hath he filled with wisdom of heart, to work all manner of work, of the engraver, and of the cunning workman, and of the embroiderer, in blue, and in purple, in scarlet, and in fine linen, and of the weaver, even of them that do any work, and of those that devise cunning work.”

So it appears the Good News Bible is actually a poor translation. Again, this is an example of Dr Leaf cherry picking something that suits her theory out of a bulk of divergent views. No matter how she tries to sell the concept, the idea that the mind controls your brain and that your thoughts control your destiny is scientifically and scripturally weak. Persistence and good marketing isn’t going to change that.

Dr Caroline Leaf and the struggle spiral

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In Proverbs 12:25, the incredibly wise King Solomon wrote that, “Worry weighs us down; a cheerful word picks us up.”

Today, Dr Leaf posted to her social media stream that “An undisciplined mind is filled with worries, fears and distorted perceptions – These lead to degeneration of the mind and body.”

Well, that’s about as uplifting as a lead balloon.

Dr Caroline Leaf is a communication pathologist and a self-titled cognitive neuroscientist.  I’m sure her heart was in the right place when she posted her latest jewel of wisdom, but it may not be as encouraging or as helpful as she may have intended.

The biggest problem is her opening premise, “An undisciplined mind is filled with worries, fears and distorted perceptions”.  So … that’s not really accurate. The normal human mind is filled with worries, fears and distorted perceptions. It really doesn’t matter whether you discipline your mind or not, you won’t shift these ‘negative’ thoughts.

That’s because we’re meant to experience appropriate levels of fear and worry.  They’re a survival mechanism.  Without a certain amount of fear, we’d end up as a Darwin Award.  And as human beings, we’re naturally inclined to so many different cognitive biases that there’s a very long list (although ironically, those with the strongest confirmation bias will probably be the least likely to accept this).

By erroneously linking normal cognitive function to the concept of mental ill-discipline, Dr Leaf is simply setting people up for an unrealistic struggle with their normal psyche as they unnecessarily try to discipline it.

And for the people who really do struggle with excessive or inappropriate worry, fear or incorrect perceptions – i.e. people who suffer from formal anxiety disorders – this sort of statement is misleading because again, their issue isn’t mental ill-discipline. Anxiety is the result of a genetic predisposition and increased vulnerability to stress.

The second part of Dr Leafs meme is as unhelpful as the first.  For a start, it’s not true that worries, fears and distorted perceptions cause degeneration of the mind and body.  There may be a correlation between stress and some long term health problems, but correlation does not equal causation.  As Cohen and colleagues noted, “Although stressors are often associated with illness, the majority of individuals confronted with traumatic events and chronic serious problems remain disease-free.” [1]  Dr Leaf’s claim seems little more than a scare tactic, which can only lead to increased anxiety not increased motivation.

The important things to remember here are:
1. Experiencing worries, fears and distorted perceptions is normal, and not something that can be changed by disciplining your mind.  Don’t fall into the trap of trying to treat something that isn’t a disease.
2. If you do suffer from an anxiety disorder, don’t blame yourself.  That sets up a spiral of struggle.  Thoughts are just words. They have no power over you unless you engage with them.  Instead of trying to repress every worry and every fear, allow your thoughts to bubble away in the background, and instead, focus your energy on taking values based committed action which will ultimately help you live a life of meaning, not just struggling.


[1]     Cohen S, Janicki-Deverts D, Miller GE. Psychological stress and disease. JAMA: the journal of the American Medical Association 2007;298(14):1685-87.

“Think and Eat Yourself Smart”: a pre-review

Update: Read my full review of “Think and Eat Yourself Smart” here.

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They say, “Never judge a book by its cover.”  What about judging it by its marketing?

Dr Caroline Leaf is a communication pathologist and self-titled cognitive neuroscientist.  She’s also a wannabe nutritionist.  Her latest book is “Think and Eat Yourself Smart”, due for official release at the end of April.

I haven’t read her book yet so I’m not really sure what she’s going to say.  It might be a well reasoned and soundly researched discussion about healthy eating, except there are some conflicting ideas that are appearing in Dr Leaf’s own marketing of the book, so I’m not holding out much promise.

For example, yesterday Dr Leaf suggested that “the mindset behind the meal – the thinking behind the meal – plays a dominant role in the process of human food related health issues, approximately 80 percent.”

This is bogus science.  It doesn’t matter if I’m convinced that eating a half gallon tub of ice cream is nutritious or not, it’s going to have the same nutritional effect on my body (namely, none).  It’s not 80 percent healthy because I believe it’s healthy.

Dr Leaf has made this assertion based on other bogus science – “How does thinking affect eating, and how does eating affect thinking? Research shows that 75 to 98% of current mental, physical, emotional and behavioural illnesses and issues come from our thought life; only 2 to 25% come from a combination of genetics and what enters our bodies through food, Medication, pollution, chemicals, and so on.”

Dr Leaf’s assertion that “75 to 98% of current mental, physical, emotional and behavioural illnesses and issues come from our thought life” is a favourite factoid of hers that forms the basis of most of her teaching.  Except that it’s wrong.  It has no basis in fact.  I’ve discussed this at length in several blogs and in my book (see here for a more detailed explanation of Dr Leaf’s 98% myth).

It’s unclear just how much of her book Dr Leaf has based on this false assumption, but the fact that it’s there in the first place sets a bad precedent for the rest of the book.

Only time will tell, of course.  I’d like to be proven wrong, but unfortunately, Dr Leafs latest book seems to be plagued with the same poor science as her other tomes.

Watch this space …

Dr Caroline Leaf – Rogue Notion

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According to a new study by Rutgers University, “Learning new cognitive skills can help reduce overwhelming negative thoughts”. So said Dr Caroline Leaf, communication pathologist and self-titled cognitive neuroscientist. She also advised that “Intentionally bringing those rogue thoughts under control is essential to mind health! And learn something new every day – develop your mind!”

So … negative thoughts are what, like an evil spy organisation, running around causing wanton destruction, overwhelming your capacity to function?

If that’s the case, then new cognitive skills must be like Tom Cruise, running, jumping, shooting and kicking their way through the negative thoughts, saving the world and getting the girl.

It’s a popular concept. As I discussed in my previous post, the power of positive thinking is culturally sanctioned Western folk psychology. We implicitly accept the idea that we have to harness positive thoughts and stop negative thoughts if we’re to overcome life’s obstacles.

However, the only rogue notions here are Dr Leaf’s.

Dr Leaf’s post sounds authoritative and sciency, but is nothing else. It’s vague, and with a bit of deeper palpation, it’s actually wrong.

Dr Leaf has gone back to her bad habit of obfuscating her references, maybe because she’s getting lost in her own hubris, or more likely, it’s much easier for her audience to see that she’s just cut-and-pasted the opening by-line of a press release again if she actually disclosed her source.

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In fact, the article is about a study from Rutgers which studied two behavioural interventions (not cognitive ones), a form of mindfulness meditation and aerobic exercise. The original publication is in the journal Translational Psychiatry [1], if you want to check it out for yourself. This article isn’t about learning cognitive skills at all. Exercise and mindfulness meditation are tried and true behavioural methods of improving mood disorders like depression, which the authors combined to assess the benefit or otherwise. Neither intervention involved challenging or fighting thoughts, or suppressing ‘negative’ thoughts, or “intentionally bringing those rogue thoughts under control”.

Indeed, the mindfulness meditation used involves “the practice of attending to the present moment and allowing thoughts and emotions to pass without judgment.” [1] Mindfulness doesn’t try to control anything.  Rather than supporting Dr Leaf’s declaration that intentionally bringing thoughts under control is essential to mind health, this study contradicts it.

Cutting and pasting doesn’t make you an expert. It’s easy to take a sciency-sounding tag line and put it in a pretty little graphic. Everyone does it. 90% of Instagram and Facebook posts these days are faux-authoritative pseudo-science memes that aren’t worth the bytes they’re made of.

Junk science is like junk food. If that’s all you consume, then you eventually become an intellectual blob of lard, stuffed full of mistruths and logical fallacies, and incapable of understanding scientific truth for yourself. Dr Leaf’s audience deserves better than junk science and it’s about time that Dr Leaf stopped pretending to be an expert, and started acting like one.


[1]  Alderman BL, Olson RL, Brush CJ, Shors TJ. MAP training: combining meditation and aerobic exercise reduces depression and rumination while enhancing synchronized brain activity. Transl Psychiatry 2016;6:e726.

Dr Caroline Leaf’s war on drugs

Today, Dr Leaf posted this on her social media feeds.  It’s clearly meant to shock and enrage her followers.

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Dr Caroline Leaf is a communication pathologist and a self-titled cognitive neuroscientist.  She’s also cast herself as an expert on mental health.

To the detriment of her followers, and sadly, to the rest of the Christian church, most people believe her.

Her most recent book, and her social media memes for the last couple of months, have made it clear that Dr Leaf is pursuing her own personal war on drugs … but prescription psychiatric drugs not the illicit kind.

Unfortunately, her attacks on prescription psychiatric drugs have amounted to nothing more than a hysterically illogical smear campaign under the guise of her concern for public safety.

Today’s offering follows the same pattern of narrow-minded hysteria.

Her main quote from was from Robert Whitaker, “Twenty years ago, our society began regularly prescribing psychiatric drugs to children and adolescents, and now one out of every fifteen Americans enters adulthood with a ‘serious mental illness’.”

Whitaker, like Dr Leaf, is an outspoken critic of modern psychiatric treatment with a poor understanding of how psychiatric medications actually work.  The statement that Dr Leaf quotes is remarkable for it’s poor logic.  The quote implies that the rise in childhood mental health is because of the rise in psychotropic medication use in children.  But correlation does not equal causation.  Even if one in fifteen Americans enters adulthood with a ‘serious mental illness’, and twenty years ago our society began regularly prescribing psychiatric drugs to children and adolescents, there’s no evidence that the psychiatric medications are actually causing the psychiatric problems.

Then there’s Dr Leaf’s emotionally charged statement that “They are even prescribing these psychoactive substances to infants!”

The New York Times article that she linked to discusses the case of Andrew Rios, a child suffering from severe epilepsy, having his first seizure at 5 months.  Though it’s clearly more complicated than just “simple” epilepsy – he’s pictured wearing a helmet which suggests that he has myoclonic epilepsy which is clearly uncontrolled. It’s also clear from the article that the child was having mood swings and violent behaviour before the anti-psychotic was given. The history of early seizures with ongoing poor control and violent behavior means that this unfortunate young boy likely has a severe and complicated neurological syndrome, quite possibly because of an underlying abnormality of his brain. And the symptoms he had which the mother claimed were from the antipsychotic were just as likely to have been night terrors, a common problem in two year olds.

In the end, who really knows?  But there’s certainly not enough in this article to clearly convict antipsychotics of being toxic or evil.

Neither is the use of antipsychotics for infants widespread.  20,000 prescriptions for antipsychotic medications sounds like a travesty, but according to the article, the real numbers are probably much less, or about 10,000, since not every prescription is filled.  Even 10,000 sounds like a lot, but that represents 0.0002% of all prescriptions in the US, and most of those scripts are not actually being taken by the child, but by their uninsured parent(s).

Indeed, as the article itself said, “In interviews, a dozen experts in child psychiatry and neurology said that they had never heard of a child younger than 3 receiving such medication, and struggled to explain it.”

So the prescribing of antipsychotics to infants is extremely rare, almost unheard of, and is only likely to be done in extreme cases where all other options have been exhausted.

That’s certainly not the impression you get from Dr Leaf’s post, which is just another misinformed smear against anti-psychotic medications.

Dr Leaf’s war against psychiatric medications is reckless.  When people who need psychiatric medications don’t take them, suffering increases, as do suicides.

It’s time Dr Leaf stopped spreading needless fear about these medications.  They help more people than they harm, people who already suffer from the stigma of having a severe mental illness.  They don’t need any more suffering stemming from Dr Leaf’s so-called “expertise”.

Does our attitude towards aging increase Alzheimer Dementia?

“I think I’m forgetting something …”
Does our attitude towards aging increase Alzheimer Dementia?

For the last few years, I’ve worked as a doctor for a number of my local nursing homes.  On my morning rounds, I would literally reintroduce myself to every second patient, because even though I’d seen them every week for the previous few months, they still couldn’t remember who I was.

And it’s not just because I have a less than memorable face.  Most of my nursing home residents had dementia.

While there are many different causes for dementia, the one first described by Mr Alzheimer in the (early 1900’s) is the best known and most feared.  It is also the most common, and is a significant drain on the nation’s economy as well as the quality of life in the twilight of years.

Recently, an article was published by a group of researchers from Yale University in the US which claimed to show that the attitude a person had towards aging contributes to their chances of Alzheimer Disease.  I first saw it yesterday on the social media feed of Dr Caroline Leaf, communication pathologist and self-titled cognitive neuroscientist.  Dr Leaf is known for her scientifically dubious assumptions that the mind changes the brain, not the other way around, and has previously publically stated that dementia was caused by toxic thinking.  This article seems to vindicate her assumptions.

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However, this article also made it onto Facebook’s trending list ands was picked up by news site all over the world (such as this article in the Australian http://goo.gl/RavbMl), so the interest wasn’t just from Dr Leaf, but also from the broader public.  And I can understand why.  No one wants to ‘grow old and senile’, or to ‘lose our marbles’.  Any potential cure or prevention for Alzheimer Dementia is worth paying attention to.

I admit, the headline intrigued me too, both personally and professionally.  I wasn’t aware that one’s attitude towards aging would contribute to Alzheimers, since Alzheimers is predominantly genetic, and the other associated risk factors have more to do with physical health (like diabetes, high blood pressure etc).  Psychological stress is a risk factor for Alzheimers in mice, but good evidence in humans has been lacking [1].

So, does negative attitudes to aging really cause stress which then leads to Alzheimers as the report suggested, or is there a much better explanation?

The scientific article that the news reports were based on is A Culture-Brain Link: Negative Age Stereotypes Predict Alzheimer’s Disease Biomarkers [2].  This study was done in two stages.  Volunteers were recruited from a larger study called the Baltimore Longitudinal Study of Aging.  At entry point, the participants answered a questionnaire about their attitudes towards aging.  This was about 25 years before the participants were actively studied.

The first study examined the change in volume of a part of the brain called the hippocampus (which plays an essential part in our memory system).  The second part of the study examined the volunteers’ brains at autopsy for markers of Alzheimer Dementia, namely ‘plaques’ and ‘tangles’.  The number of plaques tangles were combined to form a single composite score, which was then compared to the baseline attitude towards aging score.

In the first study, the researchers reported that those people who held negative views of aging were more likely to have a smaller hippocampus which more rapidly decreased in size over time.

In the second study, the researchers reported that those people who held negative views of aging were more likely to have more plaques and tangles in their brain.

On the surface, this seems to suggest that people who hold negative views on aging contribute to the development of Alzheimer Dementia, and certainly this is how the different news agencies seemed to interpret the outcomes of the study.  Though on deeper palpation, a number of questions arise about how the researchers did the study and chose to interpret the results.

For example, the aging attitude survey was only done once, which means there’s a 25 year gap or longer between the questionnaire and the active studies. That’s a long time, and the attitudes of the volunteers may have improved or worsened in that time, but that doesn’t seem to have been considered

Levy and her researchers also report that the average size of the hippocampus changed significantly when they averaged the size of the left and the right hippocampus.  But when they analyzed the two sides separately, there was no significant change over time.  So this makes me wonder about the validity of their analysis too – if the volume of each side separately doesn’t change much at all, then how can the average volume of the two sides change so much?

I’m not much of a statistician, but I wonder if the secret’s in their modeling.  They used a linear regression model to compare their data to their hypothesis, a legitimate statistical method, but which involves adjustment for other variables.  If you do enough adjusting, you can get a significant result statistically, but according to their numbers, their Cohen’s d was 0.29, which is considered a weak effect overall.

Then there’s the question of clinical significance.  Even if the hippocampus did shrink in those who thought aging was negative two decades ago, was the shrinkage enough to contribute to the cognitive impairment seen in Alzheimer Dementia?  When compared to other studies, probably not.  Looking at Levy’s graph, the “negative” attitudes group changed about 150mm3 over the 10 year follow up period, or about 5%.  A recent study also showed that the the hippocampal size of subjects with mild memory loss is about 12% less than a healthy age matched control [3].

The same problems are seen in study 2 – Levy and her researchers reported an increase in the number of plaques and tangles in the “aging is bad” group.  But her numbers are small, and not statistically strong.  And again, the question of clinical significance arises.  Plaques and tangles represent biomarkers of Alzheimer Dementia, not necessarily a diagnosis.  Normal aging brains without dementia also have plaques and tangles, and it’s the number of tangles that seem more significant for developing cognitive impairment [4, 5], not the combined score that they used in this study.

And when all is said and done, all Levy and colleagues have shown is a correlation between attitude to aging and changes in the brain.  But correlation does not equal causation.  Just because two things are associated does not mean that one causes the other.  There maybe another variable or factor that causes both observations to co-occur.

In Levy’s case, the common connecting cause could easily be neuroticism, which they discussed as a co-variant but did not say if or how they corrected for it.  The other thing they did not examine in this study is the ApoE gene subtypes, which contribute significantly to the onset of Alzheimer Dementia [6].  The action of ApoE subtypes in the brain may contribute to both negative attitudes and Alzheimers changes?

The bottom line is that Levy’s study shows a weak correlation between a single historical sample of attitude towards aging, and some changes in the brain that are known to be markers for Alzheimer Dementia some three decades later.

They’ve certainly NOT shown that stress, or a person’s attitude to aging, in anyway causes Alzheimer Dementia.  They did not correct for genetics in this study which is the major contributor to the risk of developing Alzheimers.  So the results mean very little as it stands, and further research is required to delineate the cause and effect relationship here.

So don’t stress.  It’s not definitely proven that how you view the aging process determines your risk of dementia.  There will be those like Dr Leaf who will trot out this cherry-picked little titbit of information in the future to try and justify their pretense that thought can change our brain and impact our mental health, but what the press release says and what the study shows appear to be two different things altogether.


[1]       Reitz C, Brayne C, Mayeux R. Epidemiology of Alzheimer disease. Nat Rev Neurol 2011 Mar;7(3):137-52.
[2]       Levy BR, Slade MD, Ferrucci L, Zonderman AB, Troncoso J, Resnick SM. A Culture-Brain Link: Negative Age Stereotypes Predict Alzheimer’s Disease Biomarkers. Psychology and Aging 2015;30(4).
[3]       Apostolova LG, Green AE, Babakchanian S, et al. Hippocampal atrophy and ventricular enlargement in normal aging, mild cognitive impairment (MCI), and Alzheimer Disease. Alzheimer Dis Assoc Disord 2012 Jan-Mar;26(1):17-27.
[4]       Nelson PT, Alafuzoff I, Bigio EH, et al. Correlation of Alzheimer disease neuropathologic changes with cognitive status: a review of the literature. J Neuropathol Exp Neurol 2012 May;71(5):362-81.
[5]       Jansen WJ, Ossenkoppele R, Knol DL, et al. Prevalence of cerebral amyloid pathology in persons without dementia: a meta-analysis. JAMA : the journal of the American Medical Association 2015 May 19;313(19):1924-38.
[6]       Liu CC, Kanekiyo T, Xu H, Bu G. Apolipoprotein E and Alzheimer disease: risk, mechanisms and therapy. Nat Rev Neurol 2013 Feb;9(2):106-18.