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Near Death Experiences and the Medical Literature

MIRACLE MAX: See, there’s a big difference between mostly dead, and all dead. Now, mostly dead: he’s slightly alive. All dead, well, with all dead, there’s usually only one thing that you can do.

INIGO: What’s that?

MIRACLE MAX: Go through his clothes and look for loose change.

The Princess Bride

Can you trust anyone when they purport to tell you what the medical literature says? No. As an example we will use the issue of near death experiences, or NDE’s.

We will avoid the obvious paradox in this entry, sort of the ‘everything I say is a lie paradox’ that will cause computers in the Federation to shut down.

Why am I going to comment on this issue? Well, this months Skeptic has a back and forth between Michael Shermer and Deepak Chopra about life after death.

No. I am not going to comment on whether there is life after death. I am more interested in life during life, thank you very much. I’ll let the afterlife take care of itself.

But in their point counterpoint, they both refer to a Lancet article about NDE’s and it then begs the question:

Does anyone actually read or understand the literature they quote ?

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Posted in: Clinical Trials, Neuroscience/Mental Health, Science and the Media

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On Being Certain

Neurologist Robert A. Burton, MD has written a gem of a book: On Being Certain: Believing You Are Right Even When You’re Not. His thesis is that “Certainty and similar states of ‘knowing what we know’ arise out of involuntary brain mechanisms that, like love or anger, function independently of reason.” Your certainty that you are right has nothing to do with how right you are.

Within 24 hours of the Challenger explosion, psychologist Ulric Neisser had 106 students write down how they’d heard about the disaster, where they were, what they were doing at the time, etc. Two and a half years later he asked them the same questions. 25% gave strikingly different accounts, more than half were significantly different, and only 10% had all the details correct. Even after re-reading their original accounts, most of them were confident that their false memories were true. One student commented, “That’s my handwriting, but that’s not what happened.”

Just as we may “know” things that clearly aren’t true, we may think we don’t know when we really do. In the phenomenon of blindsight, patients with a damaged visual cortex have no awareness of vision, but can reliably point to where a light flashes when they think they are just guessing. And there are states of “knowing” that don’t correspond to any specific knowledge: mystical or religious experiences. (more…)

Posted in: Book & movie reviews, Neuroscience/Mental Health

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Mercury emissions from coal-burning power plants and autism: Is there a correlation?

ResearchBlogging.orgOn April 30, outside the courthouse in Dallas, a press conference/rally was held. This particular rally was in response to a new study published by a group led by Dr. Raymond F. Palmer in the Department of Family and Community Medicine at the University of Texas Health Science Center in San Antonio, whose conclusion was that autism prevalence correlates strongly with proximity to mercury-emitting coal-burning power plants and other industrial sources of airborne mercury, the implication being that such sources of mercury may be causal or contributory to the development of autism. Unfortunately, the rally was reported by the media as though this study were slam dunk evidence that mercury environmental mercury is a definite contributor to the development of autism. For example, there is some video (also here) from local news sources of the rally, in the first of which it is stated as fact that mercury caused autism in the child featured in the story and in the second of which a mother who thinks that mercury causes autism is quoted credulously. This study has had much less play in the national news, but antivaccination activists, such as the ones at the Age of Autism website, a site whose main theme is that either mercury in the thimerosal preservative that used to be in childhood vaccines before 2002 or vaccines themselves cause autism, both promoted the rally and posted a glowing and credulous take on the study, as did “alternative medicine” and antivaccinationist website NaturalNews.com.

My first thought upon reading of this is that it is yet more vindication of the science showing that the claim that mercury in thimerosal-containing vaccines is a failed hypothesis. After all, as I have predicted time and time again, as the scientific and epidemiological evidence continued to mount that thimerosal is just plain not associated with autism or autism spectrum disorders, even the most diehard adherents to this belief are starting to realize that they were backing a losing horse, especially since thimerosal was removed from all childhood vaccines other than the flu vaccine in 2001, leaving only trace amounts from the manufacturing process and there is no sign that autism prevalence is falling. That’s why lately, their effort has shifted from primarily demonizing mercury to blaming other “toxins” in vaccines, even to the point that their efforts to demonize some ingredient–any ingredient–in vaccines often reaches ridiculous levels of blatant silliness, such as touting sucrose as one of those “toxins.” Indeed, I was puzzled. If environmental mercury is the new cause of autism, then the rationale antivaccinationists use to demonize vaccines and portray their children as “vaccine-damaged” is much less potent. Why on earth would they tout this study, which, even if a good study (and it’s not), would weaken their arguments against vaccines immeasurably and take power away from their whole new propaganda slogan “Green Our Vaccines”? The only reason I could think of is that perhaps they somehow think that if mercury in the environment can be linked to autism that maybe–just maybe–they can convince people that they were right about mercury in vaccines all along. Indeed, this seems to be the sort of tack that David Kirby took a year ago when he started arguing that mercury emissions from coal-burning power plants in China (which do reach California), coupled with mercury emission from crematoria in which cadavers with mercury fillings were burned, were contributing to the continued increase in the autism caseload in California despite the elimination of thimerosal in 2001.

But what does the study say itself? Is it good evidence that airborne mercury from coal-fueled power plants is an important contributor to the development of autism? I will argue no, because the study’s flaws are so innumerable that it is well nigh uninterpretable. For simplicity’s sake, to summarize its findings, I’ll quote a Science Daily press release about it:
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Posted in: Neuroscience/Mental Health, Public Health, Science and the Media, Vaccines

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The North Carolina Board of Medical Examiners, Dr. Rashid Buttar, and protecting the public from practitioners of non-science-based medicine

One of the most contentious and difficult aspects of trying to improve medical care in this country is enforcing a minimal “standard of care.” Optimally, this standard of care should be based on science- and evidence-based medicine and act swiftly when a practitioner practices medicine that doesn’t meet even a minimal requirement for scientific studies and clinical trials to support it. At the same time, going too far in the other direction risks stifling innovation and the ability to individualize treatments to a patient’s unique situation–or even to use treatments that have only scientific plausibility going for them as a last-ditch effort to help a patient. Also, areas of medicine that are still unsettled and controversial could be especially difficult to adjudicate. Unfortunately, with medicine being regulated at the state level, there are 50 state medical boards, each with different laws governing licensure requirements and standards for disciplining wayward physicians, our current system doesn’t even do a very good job of protecting the public from physicians who practice obvious quackery. The reasons are myriad. Most medical boards are overburdened and underfunded. Consequently, until complaints are made and there is actual evidence of patient harm, they are often slow to act. Also, in my experience, they tend to prefer to go after physicians who misbehave in particularly egregious ways: alcoholic physicians or physicians suffering from other forms of substance abuse; physicians who sexually abuse patients; or physicians who are “prescription mills” for narcotics. These sorts of cases are often much more clear-cut, but most importantly they don’t force boards to make value judgments on the competence and practice of physicians to nearly the extent that prosecuting purveyors of unscientific medicine does.

Dr. Rashid Buttar: Autism and cancer

The reason I’ve been thinking about this issue again is because last Friday it was announced that one of the most dubious of dubious physicians of which I have ever become aware, Dr. Rashid Buttar of North Carolina, was, after many years of practice, finally disciplined by the North Carolina Board of Medical Examiners. Basically, the Board restricted his practice so that he could no longer treat children or cancer patients (more on why those two particular restrictions were imposed below). Once hailed as a hero by antivaccinationists and even once having testified to the Subcommittee on Wellness & Human Rights on autism issues, he is now disgraced.

Dr. Buttar runs a clinic called the Center for Advanced Medicine and Clinical Research, which features on its front page this quote:

“All truth passes through 3 phases: First, it is ridiculed. Second, it is violently opposed, and Third, it is accepted as self-evident.”- Arthur Schopenhauer, 1788-1860.

I can’t resist mentioning that any time I see this particular quote, I know that I’m almost certainly dealing with someone who is far on the fringe, because what one first has to realize about the quote is that non-”truth” never makes it past phase one or two–and rightly so. Right off the bat, we can see that Dr. Buttar has a greatly inflated view of his own importance.
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Posted in: Cancer, Health Fraud, Medical Ethics, Neuroscience/Mental Health, Politics and Regulation, Vaccines

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The Increase in Autism Diagnoses: Two Hypotheses

A new study sheds more light on the question of what is causing the recent increase in the rate of diagnosis of autism. Professor Dorothy Bishop from the University of Oxford studied adults who were diagnosed in 1980 with a developmental language disorder. She asked the question – if these people were subjected to current diagnostic criteria for autism, how many of them would be diagnosed today as having autism? She found that 25% of them would. (Bishop 2008)

This epidemiological question has been at the center of a controversy over whether or not there is a link between vaccines (or the mercury-based preservative, thimerosal, that was previously in routine childhood vaccines) and autism. The primary evidence for this claim put forward by proponents of a link is that the number of diagnoses of autism increased dramatically at the same time that the number of vaccines routinely given to children was increasing in the 1990′s. They are calling this rise in autism an “epidemic” and argue that such an increase requires an environmental factor, which they believe is linked to vaccines.

That the number of new autism diagnoses is dramatically increasing is generally accepted and not a point of debate. The historical rate of autism is about 4 per 10,000 and the more recent estimates are in the range of 15-20 per 10,000 (30-60 per 10,000 for all pervasive developmental disorders of which autism is one type). (Rutter 2005) The controversy is about what is causing this rise in diagnoses. There are two basic hypotheses: 1) That the true incidence of autism is rising due to an environmental cause, 2) That the rise in incidence is mostly or completely an artifact of increased surveillance and broadening of the definition of autism. These two hypotheses make specific predictions, and there is much evidence to bring to bear on their predictions – this recent study only being the latest.

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Posted in: Neuroscience/Mental Health, Public Health, Vaccines

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SPECT Scans at the Amen Clinic – A New Phrenology?

Phrenology was a 19th century pseudoscience that claimed to associate brain areas with specific personality traits. It was based on palpating bumps on the skull and was totally bogus. New brain imaging procedures are giving us real insights into brain function in health and disease. They are still blunt instruments, and it is easy and tempting to over-interpret what we are seeing. In his book The New Phrenology William Uttal warns that “the excitement of these new research tools can lead to a neuroreductionist wild goose chase” and that we must be careful not to succumb to new versions of the old phrenology.

The Amen Clinics, founded by Daniel G. Amen, MD, offer SPECT (single photon emission computed tomography) scans to help diagnose and manage conditions such as attention deficit disorders (ADD), mood disorders, anxiety and panic disorders, autistic spectrum disorders, obsessive compulsive disorder (OCD), substance abuse, toxic exposure, brain trauma, memory problems, temper problems, and relationship and marital struggles.

The scans generate colored pictures of the brain that show “areas of your brain that work well, areas that work too hard, and areas that do not work enough.” They do not actually provide a diagnosis, but “must be placed in the context of a person’s life, including their personal history and mental state.” “The goal of treatment is to balance brain function, such as calm the overactive areas and enhance the underactive ones.” (more…)

Posted in: Medical Ethics, Neuroscience/Mental Health, Science and Medicine

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Cell Phones and Brain Tumors

The question of whether or not there is a link between the use of mobile phones (also called cell phones) and the risk of brain tumors has been cropping up more and more frequently in the media – every time a new study or analysis comes out. This is a very important question of public health as cell phone use is becoming more common, and brain tumors are a very serious and often life-threatening category of diseases.

Of course such questions are best answered by a dispassionate, careful, and systematic look at the science – what is the plausibility of a link and what is the evidence that there actually is one. At this point we are somewhere in the middle of studying this problem. We already have substantial data, but it is conflicting and the research community is still debating on how to get more definitive data everyone can agree upon. So at present there is a variety of opinions on the matter. The consensus seems to be that cell phones probably do not cause brain tumors, but we’re not sure, there is meaningful dissent from this opinion, and so more study is needed.

There are two types of scientific studies we can do to answer this question. The first is biological and looks at the effects of radiation, and specifically the type and strength of radiation emitted by cell phones, on cells in a test tube and on animals. This will tell us if a risk from cell phones is plausible, if there is a mechanism, and what, if any, the effects are likely to be. But this kind of data will not tell us if cell phones in fact have caused or are causing brain tumors.

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Posted in: Neuroscience/Mental Health, Public Health

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Thoughts on Neuroplasticity

I recently read a fascinating book, The Brain That Changes Itself by Norman Doidge. He describes case histories and research indicating that the brain is far more malleable than we once thought. We used to think each function was localized to a small area of the brain and if you lost that area of brain tissue the function was gone forever. We once thought you couldn’t teach an old dog new tricks. Now we know better. 

Learning a new skill actually changes the structure and function of the brain, even into old age. If you exercise one finger, the area of the brain devoted to that finger enlarges. The old concept of dedicated brain areas for specific functions no longer holds. Areas of the cortex that normally process vision can learn to process totally different inputs such as hearing. This is what happens with blind people: their hearing skills are enhanced when new neural connections for hearing invade the disused visual cortex. They may not actually have better hearing acuity, but they have learned to pay more attention to auditory input and to use it to build up a representation of the world around them.

One of the more intriguing experiments he describes was in monkeys. When sensory input nerves to one arm were severed, the monkey stopped using the arm, even though the motor nerves were intact. When the good arm was put in a sling, the monkey started using the impaired arm again.  When both arms were deprived of sensory input, the monkey used both arms.  (more…)

Posted in: Book & movie reviews, Neuroscience/Mental Health

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Do Antidepressants Work? The Effect of Publication Bias

A recent meta-analysis of the most commonly prescribed antidepressant drugs raises some very important questions for science-based medicine. The study: Initial Severity and Antidepressant Benefits: A Meta-Analysis of Data Submitted to the Food and Drug Administration, was conducted by Irving Kirsch and colleagues, who reviewed clinical trials of six antidepressants (fluoxetine, venlafaxine, nefazodone, paroxetine, sertraline, and citalopram). They looked at all studies submitted to the FDA prior to approval, whether published or unpublished. They found:

Drug–placebo differences in antidepressant efficacy increase as a function of baseline severity, but are relatively small even for severely depressed patients. The relationship between initial severity and antidepressant efficacy is attributable to decreased responsiveness to placebo among very severely depressed patients, rather than to increased responsiveness to medication.

The press has largely reported this study as showing that “antidepressants don’t work” but the full story is more complex. This analysis certainly has important implications for how we should view the body of evidence for these antidepressants. It also illuminates the possible role of publication bias in the body of scientific literature – something that has far ranging implications for science-based medicine.

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Posted in: Clinical Trials, Neuroscience/Mental Health, Pharmaceuticals, Science and Medicine

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Science by press release: A helmet to fight Alzheimer’s disease?

helmetDM2401_468x406.jpg

Recently, I’ve had a number of people bring to my attention a news story that has apparently been sweeping the wire services and showing up in all sorts of venues. It is, on its surface, a story of hope, hope for the millions of elderly (and even the not-so-elderly) who are or will be afflicted by that scourge of the mind, memory, and personality, Alzheimer’s disease. This disease is one of the most feared of diseases. A progressive and fatal disease of the brain, it robs a person of his memory and personality, until he no longer recognizes loved ones and becomes too demented to care for himself. The pathophysiology involves the accumulation in the brain of a protein known as β-amyloid, which forms plaques outside of cells, while neurofibrillary tangles believed to be due to the hyperphosphorylation of a protein known as tau develop in dying cells. The exact mechanism by which neuron death occurs is not fully understood, but over time this process leads to a decrease in the amount of gray matter in the cortex. There is no known cure, and the current treatments that we have result in at best a modest delay of the inevitable dementia that accompanies progression of the disease.

Given this grim backdrop and the general aging of the population in developed nations, it is expected that there will be a large increase in the number of people developing Alzheimer’s disease over the next few decades. Naturally, this provides a great deal of incentive to develop more effective treatments. Not surprisingly, sometimes the treatments proposed may sound somewhat outlandish and may even be somewhat outlandish. The treatment about which people were e-mailing me falls into this category, and I haven’t decided yet whether it’s science or pseudoscience. It could be legitimate. What I do know, however, is that I don’t like the way its inventors are promoting it by press conference before any evidence of its clinical efficacy in humans has been accepted by a peer-reviewed publication, leading to a flurry of stories about a new possible “miracle cure” for Alzheimer’s disease grounded in not a lot of science. I’m referring, of course, to the “Alzheimer’s helmet” developed by Dr. Gordon Dougal and his colleagues Dr. Paul Chazot and Abdel Ennaceur at Durham University. Dr. Dougal is a director of Virulite, a medical company based in County Durham in the U.K. Here’s a widely cited article from the Daily Mail that describes the device:
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Posted in: Basic Science, Medical devices, Medical Ethics, Neuroscience/Mental Health, Science and Medicine, Science and the Media

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