Mark Pine

This weekend I visited the exhibition of Depression era paintings, “1934: A New Deal for Artists,” at the Smithsonian American Art Museum. The marvelous paintings came from the Public Works of Art Project, a jobs program for artists. The exhibit shows the life of the American people in one of the first years of the Great Depression.

They are wonderful paintings in vibrant colors and sharp lines: paintings of working men with hammers, shovels, and plows; of factories, farms, docks, mines, a lumber mill, and a grain elevator; of stores in town and a barber shop; of women at home and carrying children; of cities, towns, tenements and street corners; and of the rural countryside, often blanketed with the snows of the winter of 1933-34, when the PWA Program was in progress. They pictured people at leisure, playing baseball, skating in the park, dancing in the evening, marching in a parade, sailing on the sound. They show roads, bridges, railroads, mountains, rivers, and all of America—a documentary in paint of how Americans lived in hard times.

Most of the canvasses, with flattened perspective and blocks of color—influences of both European Cubism and American folk art—were not technical masterworks, but they gave expression to the deep, unconquerable energy of the American people, the strength that climbed out of the economic abyss and went on to win enormous wars in Europe, North Africa and the Pacific.

Would the America of today have such a jobs program for artists? Would it provide work for its hard-working but unemployed people, as it did during the 1930s? It seems doubtful.

Paul Krugman, the economist and columnist at the NY Times, wrote today:

You might think, then, that doing something about the employment situation would be a top policy priority. But now that total financial collapse has been averted, all the urgency seems to have vanished from policy discussion, replaced by a strange passivity. There’s a pervasive sense in Washington that nothing more can or should be done, that we should just wait for the economic recovery to trickle down to workers.

Do we, as a people, still have the strength of purpose that we had in 1934? One thing is sure: If the jobs picture next November continues as bleak as now, the American people will vote to rebuke President Obama and this administration for their weakness and failure to live up to the strength and spirit of Franklin Roosevelt and the New Deal.

In September 1994, Republicans under the leadership of New Gingrich put out the “Contract With America,” a statement of party principles and 10 legislative goals for the political campaign that year. When Republicans gained majorities in Congress, party leaders credited the contract in contributing to the victory.

This week conservative leaders put out a new contract, a resolution expressing 10 conservative principles signed by members of the Republican National Committee on Monday. They hope that, like the 1994 document, the new one will propel them to electoral victories in the campaign next year.

The new resolutions should be called the Contract For America. But this time “contract” means to grow smaller. Here’s what it says:

• We support smaller government, smaller national debt, lower deficits and lower taxes by opposing bills like Obama’s “stimulus” bill;

I.e., we don’t want supporters of the stimulus in our party.

• We support market-based health care reform and oppose Obama-style government run health care;

I.e., we don’t want supporters of the public option in our party.

• We support market-based energy reforms by opposing cap and trade legislation;

I.e., we don’t want supporters of cap and trade in our party.

• We support workers’ right to secret ballot by opposing card check;

I.e., we don’t want supporters of unions in our party.

• We support legal immigration and assimilation into American society by opposing amnesty for illegal immigrants;

I.e., we don’t want friends and relatives of illegal immigrants and those who identify with them in our party.

• We support victory in Iraq and Afghanistan by supporting military-recommended troop surges;

I.e., we don’t want supporters of limiting or ending the Iraq and Afghanistan wars in our party.

• We support containment of Iran and North Korea, particularly effective action to eliminate their nuclear weapons threat;

I.e., we don’t want supporters of dialogue with Iran and North Korea in our party.

• We support retention of the Defense of Marriage Act;

I.e., we don’t want most gays and lesbians in our party.

• We support protecting the lives of vulnerable persons by opposing health care rationing and denial of health care and government funding of abortion;

I.e., we don’t want supporters of abortion rights in our party.

• We support the right to keep and bear arms by opposing government restrictions on gun ownership.

I.e., we don’t want supporters of gun control in our party.

The author of the new ten-point contract is James Bopp, Jr., a lawyer for James Madison Center for Free Speech, a conservative/libertarian advocacy group. Bopp has been active in the antiabortion movement and other right-wing causes.

His set of resolutions is seen by both liberal and conservative bloggers as a conservative purity test of candidates for office.

In Bopp’s case, the purity refers to political ideology, but throughout America’s history, quests for purity have had involved discrimination, segregation, and hatred of those who differ.

In the coming century the majority will differ and vary greatly in ethic composition, gender identity, and political views. If the Republicans want to exclude those who differ, let them. It will be they who lose majority support, not the Democrats.

America is evolving. Let the Republicans contract. It will lead them to extinction.

The second program of Charlie Rose’s Brain Series aired on Bloomberg TV last evening. The series is a remarkable exposition of the current state of knowledge on the structure and function of our organ of cognition. Last night’s episode focused on vision.

Our visual system is not like a camera, as Rose asserted and his for neuroscientist guests explained. The eye captures only selected light signals from the environment, focusing on the center of the visual field. And much of what we see comes from brain processes, which analyze and synthesize the information in the signals, creating perceptions.

Rose and his guests used several remarkable visual illusions to show how the system works. Ted Adelman, a Gestalt psychologist, held up a photo of seemingly random black and white spots, undecipherable as an image of anything. But then, as an electronic overlay drew an outline around a region of the spots, the image of Dalmatian dog suddenly appeared. Then, when the outline faded, one could still see the dog by directing one’s attention to the spots in that region of the photo.

In another part of the discussion, Tony Movshon used the Necker cube to demonstrate that the brain can synthesize two alternative perceptions of a cube from a set of polygonal lines in a flat plane. By shifting attention from one perception, with the front face toward the right, to the alternative perception, with the front face toward the left, one could move quickly back and forth back and forth between the perception of one cube and the other.

The scientists used the visual illusions to point to the huge and decisive role brain processes play in what we see. But I think the examples also help clear up something about consciousness itself.

Brain scientists sometimes fail to distinguish between consciousness and attention. Sometimes they use the phrase “conscious attention,” as though the two words were part of a single concept. And sometimes they use the word “unconscious” to mean outside of attention.

In my view, consciousness includes much that is not the focus of attention and is out of current awareness; consciousness is a broader concept than attention.

Consider Adelman’s photo of black and white spots. To see the Dalmatian dog in the picture, you have to direct your attention and bring it into your consciousness. You are therefore applying brain processing to the pattern of spots, which you perceive as the image of the dog.

Attention, not consciousness, is the additional brain processing. On the other hand, the consciousness of the black and white spots was present before you directed attention to the image of the dog embedded in them. And if you relax attention while looking at the dog, you might find that the image vanishes, leaving just the spots in your consciousness once again.

Attention and consciousness are different things.

In the Necker cube example, it’s the same kind of thing. The shifting perceptions of the cube illustrate some of the brain processing (focusing of attention) involved in the perceptions. But Movshon asserted it is not possible to see simply the flat pattern of the polygonal form without seeing a cube. Actually he’s not correct. I’m able to do that by relaxing a part of my attention. That relaxation of attention, paradoxically, takes some work, some concentration, because seeing the cubes is almost automatic.

With these examples and others, the program succeeded marvelously in bringing out the role of visual processing in what we see. You might say it focused attention on how we focus attention.

One of the most compelling elucidations came from Nancy Kanwisher, a scientist who investigates the localization of brain processes. She described how the recognition of faces and places is processed in small regions of neurons that are found in the same brain location in every person. The discussion made clear that many successive levels of neuronal functioning come into play, so that our brains are able to do something that seems almost instantaneous—knowing whom we see and where we are.

This episode of the Brain Series demonstrated how elaborate, extensive and multi-layered are the brain process that result in what we see. It showed that the processing is hierarchical, so that each layer of imaging builds on the less processed the preceding layer.

But in my view, it also showed that we should not confuse the processing of the images with the consciousness that contains the images. Consciousness is present at each level of processing—from the highest to the least processed of the layers of imagery. Consciousness spans the levels. And, I believe, consciousness is present in the essence of image itself—in the ground or capacity for image to exist at all.

ScienceDaily is reporting this morning the results of a study of pay-for-performance (P4P) incentive payments to physicians for improvements in health care practices and efficiencies. The researchers found that incentives tied to quality of the patient-doctor interaction and the patient’s experience overall resulted in better communication, coordination of care, and patient-staff interaction. But payments tied to the physician’s productivity and efficiency had a negative effect on those measures.

Published in the Journal of General Internal Medicine, the research from the UCLA School of Public Health surveyed patients and medical care directors in 27 California medical groups that had participated in the state’s Integrated Health Association P4P program. The study involved patients of 1,444 primary care physicians. Each year from 2004 (when the program started) through 2007, surveys were mailed to 100 patients per physician, who were randomly selected among those that visited their doctor that year.

The patients were asked about physician communication (six items), care coordination (two items), access to care (five items), and office staff interaction (two items).

Medical directors of the medical groups were questioned on the formulas they used for the incentive payments, including the percent based on productivity (e.g., patients seen per day), efficiency (e.g., limiting referrals), patient experience measures, clinical quality measures, and “other” criteria (e.g., prescribing generic medications).

The results showed that the program yielded annual improvements in physician-patient communication and care coordination scores of 11% and 7% respectively. Generally, physicians with lower scores to begin with improved the most. And they demonstrated that incentives geared to quality of care and the patient’s experience produced the most improvement. On the other hand, use of productivity incentives resulted lower scores and patient and physician dissatisfaction.

The authors suggested, “Productivity incentives might not effectively cultivate the working relationships of physicians, advanced practice clinicians, and office staff, and a weak relationship emphasis may spill over to patient care.”

The study is significant in relation to the fee-for-service system of payments, which constitutes the core of our current system of paying for health care. The system pays physicians separately for each patient, each illness, and each service performed. And a key issue in the ongoing discussion of health care reform is that the system encourages overutilization, unnecessary care and drives up costs.

In their study, the UCLA researchers found that incentive payments based on productivity and efficiency result in reductions quality of care and patient and physician dissatisfaction. Such payments reinforce the current fee-for-service system, because they encourage doctors to increase the number of patients seen, illnesses treated and services rendered.

In contrast, the research showed that incentives based on quality of patient care and patient-physician interaction result in improvements in those measures. The study implies, therefore, that our nation’s current fee-for-service payment system probably reduces quality of care and patient and physician satisfaction nationwide.

It’s about time.

Lisa Birnbaum, a toxicologist, became Director of the National Institute of Environmental Health Sciences (NIEHS) and the National Toxicology Program about a year ago. This past week Scientific American posted an interview with her online.

In the interview, Birnbaum said she intends to focus the work of the institute on the effects of industrial chemicals contaminating our environment. Of the more than 80,000 compounds used in business, few have been carefully screened for effects on the biology of humans and other living creatures. That will be changing under Birnbaum. Moreover her thrust will reinforce other work under Lisa Jackson, the new Administrator of the Environmental Protection Agency, which is also stepping up the effort to examine environmental pollution by chemicals used in businesses and manufacturing.

Bisphenol-A (BPA) will be one the first substances investigated. The chemical has been widely used in food containers, particularly clear polycarbonate water bottles and baby bottles. It acts as a weak estrogen and is considered a disrupter of endocrine function. About a decade ago, Patricia Hunt, a geneticist at Case Western, discovered the hormonal effects of BPA on reproduction and genitalia in mice.

More recently questions have been raised about its effects on the breast, the prostate and immune systems, including possible carcinogenic activity. At the current levels of the chemical in our environment, the NIEHS has so far concluded that most of the concern relates to exposure of fetuses, infants and children and to effects on the development of the brain, behavior and the prostate gland. Additionally, the FDA, which licenses BPA for use in food packaging, is currently reviewing the latest science on the compound, and the agency may announce conclusions in the near future. However, most toxicologists agree that still more research on BPA should be done.

A number of excellent foods, which I eat regularly, are sold in cans lined with BPA—one reason why I’m dismayed by its common use and the controversy about the chemical. A vegetarian except for fish and shellfish, I make beans a main ingredient of many of my meals. But unfortunately, canned beans, which are far superior in texture, taste, and ease of preparation to dried beans, usually come in cans lined with BPA. Another ingredient I use often is greens (collard, mustard, turnip), which are marketed by the Richfood company in cans lined with BPA. But for the probability of BPA seeping into the product, the quality of the greens is excellent. Moreover, Richfood is the only company that prepares its greens without adding large quantities of salt. And the fish that is the only flesh I consume … unfortunately some of it also comes in cans lined with BPA. I have many reasons for concern.

The NIEHS, NTP, and EPA plan to assess risks associated with many other chemicals, as well. The first phase of work will focus on chemicals in five classes: Phthalates, used in cosmetics and vinyl; brominated flame retardants used in electronics and textiles; perfluorinated compounds used in nonstick coatings; some parafins used in lubricants; and benzidine dyes and pigments. Many of these compounds are thought to be endocrine disrupters like BPA.

European regulatory and scientific agencies are ahead of their American counterparts in environmental toxicology work. In 2007, the European Chemical Agency began a program called REACH, for regulation, evaluation, authorization, and restriction of all chemicals used in products, industrial processes, and daily life. The manufacturers producing the chemicals must do the research, but the regulations that result will cover the European Union. Many of the chemicals of concern to U.S. authorities may be evaluated in Europe first.

So often these days European governments seem to have jumped to lead in efforts to improve public welfare, when those efforts might infringe on the profitability of businesses. The U.S. government sometimes seems more concerned with corporate than public welfare. One encouraging things, however, is that the sooner-available European results of research on chemicals toxicities will also be useful to American regulatory agencies.

Last March, a study done by the NIH and AARP, published in the Archives of Internal Medicine, looked at diet and health in half a million middle-aged and older Americans. Those who ate 4 ounces of red meat or more per day had a 30% higher mortality rate during the next 10 years. Health is certainly one thing to consider when deciding whether to eat meat.

Another thing one might consider is energy cost. According to Appropedia , a web wiki devoted to sustainable living issues, production of a pound of beef releases 14 times as much CO₂ as a pound of fruits and vegetables. And a Wikipedia article compares the energy cost of producing animal protein to that required for plant protein:

The production of protein from grain-fed animals requires eight times as much fossil-fuel energy as the production of plant protein. … Typical feedlot husbandry of cattle requires an input of 35 kcal of fossil fuel to produce one kcal of food energy in beef, far more than that required for comparable plants.

In addition, many people (myself included) consider moral issues in deciding whether to eat meat. Yesterday, in the NY Times, Gary Steiner, a philosopher at Bucknell, raised the issue of how animals are treated on farms. In deciding whether to eat meat, he asks if we should be concerned whether the flesh we consume comes from animals that spend their lives in cages or pens, unable to wandering, feed, and reproduce.

But though he is concerned about the treatment of farm animals, that is not Steiner’s main objection. In his view:

Most people just don’t care about the lives or fortunes of animals. If they did care, they would learn as much as possible about the ways in which our society systematically abuses animals, and they would make what is at once a very simple and a very difficult choice: to forswear the consumption of animal products of all kinds.

Steiner is a ethical vegan, someone who chooses to eat no meat whatsoever because of he believes it is immoral. He writes that some people don’t object to animals suffering on farms because they don’t believe the suffering of animals is on the same level as human suffering. Some others cite religious justifications for using animals as food.

And dealing with a third common justification, Steiner writes, “Others argue that the human capacity for abstract thought makes us capable of suffering that both qualitatively and quantitatively exceeds the suffering of any non-human animal.” On the other hand, “people who are ethical vegans believe that differences in intelligence between human and non-human animals have no moral significance whatsoever.”

I agree with Steiner to some extent. I believe society and science have progressed to the point that we can no longer ignore many issues in deciding what to eat, questions regarding human health and environmental consequences. And we can no longer close our eyes to the treatment of animals on farms, as some journalists have described.

About four years ago, I decided to refrain from eating the meat of land animals. As a physician, most of my concern at that time came from worries over my long-term health as I grow old. But also I was and continue to be troubled by the terrible treatment of animals on industrial farms and the degradation of the environment around those animal factories.

However, I’ve decided to draw the line at a different place from Steiner. I continue to eat fish and shellfish. One reason is that fish oils have been shown to be good for the cardiovascular system.

Moreover, unlike Steiner, I do think intelligence is relevant in deciding what to eat. It’s my guess that most land animals, both mammals and birds, are more intelligent than most fish, and certainly more intelligent than shellfish.

The capacity of an animal for intelligent reflection, in my view, confers moral value. I don’t object to killing insects or using worms for fish bait. I don’t object to fishing, although I am concerned about those fishermen who do so just for sport, returning the fish to the water after making a catch. And since I don’t think plants possess a capacity for reflective intelligence, I have no objection to eating fruits or vegetables.

Steiner might contend that my placing value on the capacity for intelligent reflection comes from my human perspective, since that’s what we humans excel in and value highly. I wouldn’t disagree. But I would ask him why as an ethical vegan, he draws the line between animals and plants. Plants are alive as animals are, yet he is willing to kill plants for food. If intelligence is not his basis for his making that distinction, then I wonder what what is?

Yes, one more bad thing you might get from smoking cigarettes. Cigarettes contain germs, according to a new study.

As reported in ScienceDaily online, researchers from the University of Maryland and the National Institute of Environmental Health Sciences looked for microbes in four brands of cigarettes: Camel, Kool Filter Kings, Lucky Strike Original Red, and Marlboro Red. They found evidence of germs known to cause pneumonia, infections of the blood, and other infectious diseases. Some of the bacteria they found are notoriously difficult to treat, such as Pseudomonas aeruginosa, which is often present in hospital-acquired infections. Anthrax bacteria were also detected.

The scientists wrote in the paper (available open access online in Environmental Health Perspectives)

Over 3,000 chemical, heavy metal and other constituents have been isolated from tobacco and the overwhelming majority of studies that have investigated adverse health impacts associated with cigarette smoking have focused on the role of these compounds, as well as particulate matter, on pulmonary and systemic pathophysiologic changes that can lead to disease. Few studies however, have investigated bacterial components of cigarettes and their possible roles in smoking-associated illnesses.

For reasons not explained, the researchers used packs of cigarettes purchased in 2007 in Lyon, France. They extracted DNA from five cigarettes from each pack, and sequenced, amplified and identified bacterial DNA.

Bacterial DNA was found in every cigarette.The organisms included Actinobacteria, Bacteroidetes, Chloroflexi, Cyanobacteria, Firmicutes, Proteobacteria, Betaproteobacteria, Deltaproteobacteria, and Gammaproteobacteria). All the brands yielded similar types of organisms.

So … is this just one more finding in a never-ending list of horrible (and yawn-inducing) cigarette things? This latest one, though, might really rattle young people who get curious to try one. I suspect that teenagers flirting with smoking might find it really abhorrent to think about inhaling germs.

We are conditioned against germs from the earliest ages, when our moms and dads tell us not to put dirty things in our mouths because of germs. They show disgust when food is spoiled or contaminated. We begin to learn about germs from such a young age that the fear of them makes its way to the core of our being.

So let’s use this new finding to try to help prevent people from starting to smoke. Let’s publicize the fact on the TV, in cigarette ads and on the packs themselves. Let them say: “Cigarettes Contain Germs,” perhaps along side pictures of people coughing gunk.

Harry Reid was able to thread the health care needle while the thread was blowing in shifting political winds. It’s quite an achievement. The majority leader stands a good chance of picking up the support of reluctant Democrats Ben Nelson, Mary Landrieu, and Blanche Lincoln to move the legislation onward to floor debate.

There’s a lot to like in Harry Reid’s synthesis of the Senate health care bill.

• Extending coverage to 31 million people without insurance.
• Exchanges for people to compare plans and prices when they buy insurance.
• Banning insurance practices that deny coverage for preexisting conditions or for getting very sick.
• Mandating coverage both for individuals and businesses, with fines for not participating
• A public health insurance plan, which states could opt out of. (Cynical aside: Probably southern states with poorer, sicker populations would opt out. Doesn’t make sense for them, but it’s their choice. The rest of the nation would save money on health care.
• Abortion restrictions that act by segregating federal funds but continue to allow private funding of coverage.

The bill is paid for by raising the payroll tax on the highest income earners and by taxing the most generous plans and cosmetic enhancement surgery. It tries to avoid burdening the future with more debt.

Indeed, the Congressional Budget Office projected that the bill would reduce federal deficit by $130 billion over the next decade. That finding is great for boosting support for the bill and weakening opposition.

I don’t believe the CBO, however. Genuine savings, in my view, will come instead from reducing the rate of growth of health care costs. That will come about—not from taxes and cost reductions now in the bill—but from establishing a structure for oversight of the health care system.

For example, consider Reid’s decision to include something brand new and not discussed much to date: A voluntary insurance program for long-term care. Including such a program would certainly not cut the health costs paid by the federal government. — In fact it might lead to a new entitlement. But it does exemplify the legislation’s change of attitude. As the boomer generation ages, long-term care will become a bigger issue. Rather than ignoring the problem until it overwhelms, Reid’s bill begins to try to deal with it now.

In the long run, that may be the most important thing bill does. It expresses a new analytical, supervisory attitude toward the health care system and creates a new structure for dealing with it. Rather than waiting for health care problems to reach crisis or letting the market deal with them (the failed approach of the last four decades, which the Republicans are fighting to continue), the government will begin to plan health care rationally.

For these reasons, if health care legislation passes, we should all exhale with relief.

(This posting was sourced from articles in the NY Times and the Washington Post.)

Science writers love to write skeptically about free will. In the November issue of Scientific American Mind, reporter Christopher Koch explains why:

Surely there must have been times in high school or college when you laid in bed, late at night, and wondered where your “free will” came from? What part of the brain—if it is the brain—is responsible for deciding to act one way or another? One traditional answer is that this is not the job of the brain at all but rather of the soul. Hovering above the brain like Casper the Friendly Ghost, the soul freely perturbs the networks of the brain, thereby triggering the neural activity that will ultimately lead to behavior.

Although such dualistic accounts are emotionally reassuring and intuitively satisfying, they break down as soon as one digs a bit deeper. How can this ghost, made out of some kind of metaphysical ectoplasm, influence brain matter without being detected? What sort of laws does Casper follow? Science has abandoned strong dualistic explanations in favor of natural accounts that assign causes and responsibility to specific actors and mechanisms that can be further studied. And so it is with the notion of the will.

In the article, Koch writes of the “sensation of agency.” It’s the feeling you get when you initiate an action, like deciding to move a part of your body—the feeling of acting voluntarily. Koch asserts that such sensations are “no different, in principle, from any other consciously experienced sensations, such as the briny taste of chicken soup.”

He reports that during certain brain operations, the surgeons are able to elicit this kind of feeling of agency by stimulating the brain with electrodes. Surgeons have elicited such feelings when stimulating the presupplementary motor and the posterior parietal regions of the cerebral cortex. Koch also points out that sensations can sometimes be illusory or mistaken.

But does this imply that the feeling of having free will is an illusion? Actually Koch doesn’t make this claim this, and to his credit he writes:

Lest there by any misunderstanding: the sensations of the intention to act and of agency do not speak to the metaphysical debate about whether will is truly free … whether free will has some ontological reality or is entirely an illusion

Leaving aside the question whether the feeling of agency is just like tasting chicken soup, the fact that such a feeling can be triggered by electrical stimulation of the brain implies nothing whatsoever about whether free will exists. The brain could not give rise to a feeling unless it were possible to induce it by stimulating the same neurons electrically. That an electrode can produce a feeling of agency yields no information about whether I can elicit it myself through the exercise of my free will.

Koch main thesis, however, is the one he explains in the first paragraphs of the piece. Raising the specter of a ghostly soul, he asks what sort of [physical] laws Casper-the-Ghost-of-free-will would follow.

Leaving aside Koch’s condescension toward one of the greatest debates of all time—whether there exists a soul and a free will—it’s true that his question is central and important to the debate, and it requires an answer. I will attempt one here. But I must suggest an answer without explaining all my reasons for it, since it would be impossible in the space available.

Boiling down Koch’s question, he asks, Does it make rational sense, within the context of physical science, to consider the possibility of a immaterial substance (a free will) that can influence physical reality (moving a part of the human body).

In my view, it does indeed make sense in quantum mechanics.

In QM, everything that exists has a wave form and a particle form. This is the wave-particle duality, a central principle of QM. (Duality is also a central principle, albeit a philosophical one, in the soul-body debate, as Koch notes.)

The wave form, however, is an immaterial entity. It is a mathematical function—conceptual and non-material. Yet according to QM, the immaterial wave function influences physical reality by specifying the probabilities of the forms physical reality can assume. Moreover, the wave function gets transformed into physical reality through a process called “collapse”—as described in the usual Copenhagen interpretation.

Here is the suggestion: The exercise of free will involves an intention, which exists as the wave function of the brain at that moment. When the intention is carried out, the brain wave function collapses into the physical state of the neurons that carry out the intended action.

This suggestion, I believe, provides a basis in physics for dealing with Koch’s main issue. QM allows for the scientific consideration of an immaterial essence—the wave function—that in Koch’s words, “perturbs the networks of the brain, thereby triggering the neural activity that will ultimately lead to behavior.”

We go for a screening test for cancer (those of us who choose to do so) because we hope that, in the unlikely event that we have the disease, by detecting it early while its small and before it spreads, we have a better chance of being cured. It makes sense.

So it’s a surprise to find out that in some cases screening may do as much harm as good. The reason that’s so comes from the basic arithmetic of screening tests.

Screening tests are offered to large populations, in which the rate of disease is low. But no test is perfect, and a screening test sometimes detects disease when there is none (called a false positive test). Since most people tested don’t have the disease, even a low rate of false positive tests may result in an unacceptably large number of individuals who are actually healthy but who go unnecessarily go through more tests, get unneeded treatment, and experience the emotional turmoil of facing a serious illness.

In the younger age groups of women, mammography screening is a case in point. Yesterday, the U.S. Preventive Services Taskforce (USPSTF) recommended against routine mammography of women 40-49 years old. The new recommendation, which reversed a previous recommendation for screening women in the age group, was reported in the NY Times and other media.

The USPSTF provided data on its website to support its recommendation.

Mammography will detect about 85% of breast cancer in women who have it (that’s called the sensitivity of the test). And it will rule out the disease in about 95% of women who don’t have it (the specificity of the test).

At age 40, about 1.4% of women will get breast cancer in the next 10 years. So if a clinic tests 1000 women 40-49 with mammography, it picks out 0.85 x 14 = 12 women who have breast cancer. That leaves 988 women (two of whom have undetected disease).

And the clinical will correctly rule out breast cancer in 0.95 x 986 = 937 women who don’t have it. Consequently, the test also picks out 49 women who don’t have the disease but who don’t get a clean bill of health either. Those women may be subjected to more tests, treatment they don’t need, and misplaced fear and worry.

In this case, twelve women get appropriate treatment for cancer, but four times as many healthy women may be harmed by the test. Is that an acceptable result?

The judgment of what’s acceptable and what’s not is ultimately subjective, and different people may come to opposite conclusions.

In making its recommendation, the taskforce also considered what happens when the same calculations are done for women 50-59. There result is somewhat different. In that age group the 10-year occurrence of breast cancer is about 2.4%. Testing 1000 women in that group, the clinic would find breast cancer in 20 women who have it (but miss cancer in 4 women). And it would fail to rule it out in 49 women who don’t have the disease, the same number as in the younger age group.

In the 50-59 age group, therefore, the ratio of the number of women who go through further testing, treatment and turmoil unnecessarily to the number who correctly get needed testing and treatment is less than 2.5:1.

Where do you draw the line?

The USPSTF also considered the effects of mammography in boosting rates of cure for women with breast cancer. For women in both 39-49 and 50-69 age groups, the benefit of mammography is about the same: a 14-15% reduction of mortality, which is not remarkably effective. The task force calculated that about 1900 women aged 40-49 would have to be offered testing to prevent the death of one women, but offering testing to about 1300 women aged 50-59 would have a the same effect.

In my view, the new recommendation is a correct one. In the 40-49 age group, too many women get unneeded treatment and experience unnecessary fear and anxiety in comparison to the number who are helped by the test. But I recognize that as a man, I may not be in the best position to make this judgment.

However, the situation is somewhat similar (but even more problematic) for men undergoing PSA screening for prostate cancer. This is a situation I do deal with.

A large majority of men tested with PSA either don’t have the disease or have a benign condition that also results in a positive test. Consequently, the inaccuracy of the PSA test may result in many men experiencing fear and getting treatment needlessly.

In 2002, the USPSTF found that although PSA screening does detect early-stage prostate cancer, it doesn’t improve outcomes of treatment. In 2007, an updated analysis of PSA screening noted that false positive tests can cause psychological harm. And it confirmed the earlier analysis that early detection doesn’t result in improved outcomes.

So, will I choose not to get tested with PSA if offered the opportunity? I’m not sure. But perhaps a better choice is having my prostate removed. At my age, I done with children but I experience common urinary problems attributable to an enlarging gland. What does my prostate do for me but provide a place for a cancer to grow?