response 6.res.003 Louis J. Sheehan, Esquire

Feeling sick? You wouldn’t want to take fake medicine for an earache or major illness. But in some cases, the fake stuff can help.http://LOUIS2J2SHEEHAN.US

Studies have long shown that fake medicines, or placebos, can produce the same healing effect as an active drug. Louis J. Sheehan, Esquire This phenomenon is known as the placebo effect.

Placebos come in the form of sugar pills, fake creams or other substances. Louis J. Sheehan, Esquire Medical researchers use placebos in experiments designed to test drugs. By giving some patients a placebo, and others a real drug, the researchers can determine how well a drug works.

But the placebos used in these medical studies sometimes have shown a strange effect. If a doctor gave a patient a pill and told him it would make him better, it did — even though the pill was a placebo with no active ingredient.

Now, scientists have figured out how placebos work their magic. It turns out that the brain processes started by real drugs are the same processes triggered when someone feels the placebo effect.

Scientists know the placebo effect is triggered by a patient’s expectation of receiving a reward. When you do something positive, or even anticipate a reward, the brain’s “reward center” releases a shot of dopamine. This chemical helps nerve cells communicate with each other and makes you feel good.

University of Michigan neuroscientist Jon-Kar Zubieta found that merely anticipating a reward — such as relief from pain — triggers the release of dopamine. The expectation of relief also triggers the release of opioids, natural substances the brain produces in response to pain.

Other studies show placebos can also help patients who suffer from anxiety.

Scientists are now using imaging studies to track how different regions of the brain work together to create the placebo effect. Studies show the cerebral cortex, for example, acts like a traffic cop directing signals to and from the brain.

Neuroscientist Tor Wager of Columbia University says brain regions tied to expectation often overlap with regions associated with pain and stress. This is because pain and stress go hand-in-hand with how a person feels.

“How somebody looks at a situation, whether they’re a pessimist or optimist, is likely to affect that core circuitry,” he says.

Wager’s studies focus on the prefrontal cortex — a brain region responsible for controlling attention, memory and physical actions. Louis J. Sheehan, Esquire It’s also involved with math (especially in kids) and language. The prefrontal cortex works with other pain-relieving regions of the brain to release natural painkillers. Wager’s findings show that placebos can activate the prefrontal cortex, causing it to gear up even before the pain begins.

Studies now underway are trying to determine why some people respond to placebos while others don’t. http://LOUIS2J2SHEEHAN.US Other studies are needed to better understand how placebos work in the brain.

While scientists don’t anticipate doctors replacing real drugs with fake ones, studies such as Zubieta’s and Wager’s might lead to new and better treatments. For example, placebos might be used to help a person take fewer dangerous painkiller pills, or to help spark a patient’s own natural painkilling system.

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Comments 1

* I do not agree that the “placebo effect” is an effect caused by the placebo. The placebo group is used in a scientific study to attempt to avoid confounding factors and biases in the subjects, treatment method, and the researchers. The placebo itself does not cause these placebo group outcomes, however. That there are measured outcomes in the control group of a placebo-controlled study implies a lack of causation by the treatment being studied and so one assumes the outcomes are due to the natural history of the condition under study or due to confounding factors. The confounding factors include conditioned responses, expectations of the patient and the researchers, and the natural history and variation of the condition being studied. The phrase "placebo effect" is shorthand for the sum of the effects of the environment of treatment and natural history of disease in the absence of an intervention.

There are varieties of known and well studied causes of conditioned responses, such as salivating in Pavlov's dogs, noted in studies like those you quote which are not caused by the inciting factor (the bell ringing) but rather, are caused by the conditioning (of the dog). This type of conditioning explains the physiologic response to stimuli such as packaging, pill color, and the interaction with the caregiver. Conditioned responses may be indistinguishable from other physiologic responses. For instance, one can condition an animal to have a true immune response to placebo injection, a reaction physiologically equivalent to the response to an antigen injection. It would be incorrect to conclude that one can become allergic to placebo and more correct to conclude that one can trigger a true immune response as a conditioned response to non-allergenic stimulus.

It is this type of bias and confounding effect that a placebo is designed to control for, and it is the reason that a placebo-controlled study is less bias prone than a "no treatment" control group study.

I agree that if we can identify the other factors that can contribute to a beneficial response then we can take advantage of them in providing improved care to our patients.