Scientific American Topic - Pain

What causes chest pain when feelings are hurt?

Fri, 19 Feb 2010 09:00:00 EST

When people have their feelings hurt, what is actually happening inside the body to cause the physical pain in the chest? -- Josh Ceddia, Melbourne, Australia

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Beyond the sugar pill: Are doctors misusing the placebo effect?

Thu, 18 Feb 2010 18:30:00 EST

Would you feel better if, besides giving you a pill, your doctor also explained some potential benefits? [More]

Running barefoot is better, researchers find

Wed, 27 Jan 2010 15:25:00 EST

Mother Nature has outpaced science once again: the bare human foot is better for running than one cushioned by sneakers. What about those $125 high-tech running shoes with 648 custom combinations? Toss 'em, according to a new study published online January 27 in the journal Nature ( Scientific American is part of Nature Publishing Group). [More]

Discouraging data from the first rigorous study of platelet-rich plasma therapy

Thu, 14 Jan 2010 14:00:00 EST

The results of the first randomized controlled trial looking at the effectiveness of platelet-rich plasma (PRP) are out, and they fail to support the therapy sought by many amateur and professional athletes alike, including Tiger Woods . An injection of PRP was no better than a saline injection in alleviating pain and aiding recovery among a group of Achilles tendonitis sufferers, according to the study published January 13 in the JAMA The Journal of the American Medical Association . [More]

Reviving Consciousness in Injured Brains

Wed, 13 Jan 2010 09:00:00 EST

Most scholars concerned with the material basis of consciousness are cortical chauvinists. They focus on the two cortical hemispheres that crown the brain. It is here that perception, action, memory, thought and consciousness are said to have their seat.

There is no question that the great specificity of any one conscious perceptual experience--such as the throbbing pain of the socket following extraction of the lower right wisdom tooth, the feeling of familiarity in déjà vu, the aha experience of sudden understanding, the azure blue of a high mountain vista, the despair at reading about one more suicide bombing--is mediated by coalitions of synchronized cortical nerve cells and their associated targets in the satellites of the cortex, thalamus, amygdala, claustrum and basal ganglia. Groups of cortical neurons are the elements that construct the content of each particular rich and vivid experience. Yet content can be provided only if the basic infrastructure to represent and process this content is intact. And it is here that the less glamorous regions of the brain, down in the catacombs, come in.

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Daring to Die: The Psychology of Suicide (preview)

Tue, 12 Jan 2010 09:00:00 EST

At age 18, Erica Hernandez tried to kill herself--twice. Depressed and plagued by family problems, she first took “every pill in the house,” she says. Then she attempted to drink herself to death. But whether through luck or indecision, her attempts were not drastic enough to end her life before help arrived. Now age 31, Hernandez has found “peace” through her church and a parent-child psychotherapy group she has joined.

Every year millions of people around the world try to kill themselves--and nearly one million of them succeed. Suicide is the 11th biggest killer of Americans and the third-leading killer of 15- to 24-year-olds. The U.S. suicide rate is increasing for the first time in a decade, primarily as a result of the rise in the practice among whites aged 40 to 64, according to a new report covering the years 1999 to 2005 from the Center for Injury Research and Policy at the Johns Hopkins Bloomberg School of Public Health. The economy is now adding to the problem: the chief financial officer of Freddie Mac killed himself last April, and so have some Americans who have been evicted from their homes. The U.S. government’s National Suicide Prevention Lifeline, begun in 2005, is also getting record numbers of calls: 57,625 in August 2009, up from 47,191 the same month a year before.

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EPA Proposes Tougher Standards for Smog

Thu, 07 Jan 2010 16:26:00 EST

U.S. EPA today proposed significantly tougher smog standards after reconsidering the George W. Bush administration's controversial 2008 regulations.

The draft rule released by EPA proposes to revise the two standards aimed at protecting public health and welfare to comply with recommendations made by the agency's science advisers. The Bush administration had rejected those suggestions when issuing the 2008 national air quality standards for ground-level ozone, or smog, drawing criticism and legal challenges from environmental and public health groups.

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Readers Respond to "The Social Cure"--And More...

Thu, 31 Dec 2009 11:00:00 EST

Social Exhaustion In “ The Social Cure ,” Jolanda Jetten, Catherine Haslam, S. Alexander Haslam and Nyla R. Branscombe state: “Membership in lots of groups--at home, work, the gym--makes us healthier and more resilient.” But we are not all the same. For extroverts that formula makes sense, but for introverts it does not. Unlike extroverts, who are energized by social mingling, introverts typically find the experience at the least uncomfortable and, more often than not, downright exhausting. [More]

What a Colored Square Taught Me About Defeating Fear

Tue, 29 Dec 2009 14:00:00 EST

Every time that a colored square appeared on the monitor in front of me, I braced for pain. Early into the 10-minute session as a subject of this experiment, I learned that about half of the times that I saw that square, I received a low-voltage shock, via a bar strapped to my right wrist. I also learned that every time I saw a square of a different, "good" color, I could momentarily breathe easy. But in the second day's session, as I watched the squares appear in random order, no shocks punctuated either the "bad" or "good" colors. After several minutes I started to relax. [More]

When Fear Makes Us Superhuman

Mon, 28 Dec 2009 11:00:00 EST

Editor's note: The following is an excerpt from Extreme Fear: The Science of Your Mind in Danger by Jeff Wise, published on December 8 by Palgrave Macmillan ( Scientific American is a Macmillan publication). Extreme Fear explores the neural underpinnings of this powerful and primitive emotion by relating instances in which people were forced to act under duress and presenting the latest findings from cognitive science. In the following passage from the chapter entitled "Superhuman" a seemingly ordinary man performs an extraordinary feat of strength to rescue a cyclist who has been run over by a car. [More]

How to Cure 1 Billion People?--Defeat Neglected Tropical Diseases

Mon, 21 Dec 2009 08:00:00 EST

In the north of Burkina Faso, not far to the east of one of the best-known backpacker destinations in West Africa, the Bandiagara Escarpment in Mali, lies the town of Koumbri. It was one of the places where the Burkina Ministry of Health began a mass campaign five years ago to treat parasitic worms. One of the beneficiaries, Aboubacar, then an eight-year-old boy, told health workers he felt perpetually tired and ill and had noticed blood in his urine. After taking a few pills, he felt better, started to play soccer again, and began focusing on his schoolwork and doing better academically.

The Burkina Faso program, which treated more than two million children, was both a success story and an emblem of the tragedy of disease in the developing world. For want of very simple treatments, a billion people in the world wake up every day of their lives feeling sick. As a result they cannot learn in school or work effectively.

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Is Platelet-Rich Plasma an Effective Healing Therapy?

Fri, 18 Dec 2009 17:24:00 EST

Torn tendons, muscles and ligaments plague athletes in many types of sports. In attempts to help heal the wounded tissue, some athletes, both amateur and professional, have turned to platelet-rich plasma (PRP) therapy. For the treatment, doctors take a small vial of a patient's blood, about 30 milliliters, and spin it in a centrifuge to separate the platelet-rich plasma from the other components. Then they inject the concentrated platelets at the site of the patient's injury. In theory, the growth factors that platelets secrete (not including human growth hormone) spur tissue recovery. [More]

The Double Life of ATP in Humans (preview)

Mon, 14 Dec 2009 08:00:00 EST

One of the first and most enduring facts most students learn in biology class is that all living cells use a small molecule called adenosine triphosphate (ATP) as fuel. That universal energy currency drives the biological reactions that allow cells to function and life to flourish--making ATP a crucial player in the biological world.

Less commonly known, however, is that what is perhaps the most produced and consumed molecule in the human body also has a completely separate but no less essential role outside of cells. A long series of discoveries has now demonstrated beyond doubt that ATP is a critical signaling molecule that allows cells and tissues throughout the body to communicate with one another. The universal fuel, in effect, serves as a common language as well.

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Depression's Evolutionary Roots (preview)

Tue, 01 Dec 2009 09:00:00 EST

Why do so many people suffer from depression? Research in the U.S. and other countries estimates that between 30 to 50 percent of people have met current psychiatric diagnostic criteria for major depressive disorder sometime in their lives. This staggeringly high prevalence--compared with other mental disorders that affect only around 1 to 2 percent of the population, such as schizophrenia and obsessive-compulsive disorder--seems to pose an evolutionary paradox. The brain plays crucial roles in promoting survival and reproduction, so the pressures of evolution should have left our brains resistant to such high rates of malfunction. Mental disorders are generally rare--why isn’t depression?

This paradox could be resolved if depression were a problem of growing old or a result of our modern lifestyles. Aging cannot explain depression, however, because people are most likely to experience their first bout in adolescence and young adulthood. So perhaps depression is like obesity--a problem that arises because modern conditions are so different from those in which our ancestors lived. But this explanation is not satisfactory, either. The symptoms of depression have been found in every culture that has been carefully examined, including societies such as the Ache of Paraguay and the !Kung of southern Africa--societies in which people are thought to live in environments similar to those that prevailed in our evolutionary past.

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Why do human testicles hang like that?

Thu, 19 Nov 2009 18:06:00 EST

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The AMA eases its stance on marijuana

Tue, 17 Nov 2009 11:00:00 EST

The Obama administration announced last month that people who buy or sell medical marijuana in the growing number of states that have decriminalized its therapeutic usage should not be targeted for arrest or prosecution by federal authorities. Now, the American Medical Association (AMA) has called for the federal government to go one step further in easing restrictions, the Los Angeles Times reported last week . [More]

Who says love hurts? Romantic partners alter our perception of pain

Thu, 12 Nov 2009 17:26:00 EST