Why Placebo? The placebo effect is more than a strange curiosity. It is the foundation of much of modern medicine. Yet we know almost nothing about it. That's why this blog tracks the illusive placebo and shows how it is tied to almost every facet of health.
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 Here’s a heartwarming picture for you. A small autistic child, totally cut off from the surrounding world is brought to a sunny Florida marine park. He fiddles with his backpack straps and refuses to acknowledge anyone around him. He’s then wet-suited up and tossed in a pool with a live dolphin, who proceeds to swim over and check him out and then gives him a ride on his back on command from the trainer.
Afterward, the little child looks at his parents and smiles.
Wow, right? What a powerful story of nature healing sickness and the bond between two wayward creatures. But is it true? So called “dolphin assisted therapy” has sprung up over the past decade as the hip treatment for affluent parents of developmentally disabled kids. They vary in price, but according to the Washington Post, most seem to charge a couple thousand dollars for 4-5 daily sessions in the pool.
Let’s leave aside for a second the debate over whether it’s right to keep captive dolphins and focus on whether there is any science to back up the claim that frolicking with dolphins has lasting therapeutic value.
Lori Morino, a well respected neuro-anatomy professor at Emory University and vocal critic of dolphin assisted therapy, calls them “sleazy organizations” that are taking advantage of desperate parents. She was an author of a 2007 review paper that looked at five papers examining the practice. Four of these gave it a shining review, the fifth, a hesitant one. Marino and co-author Scott Lilienfeld, however, had a different take. They weighed the studies against a dozen or so accepted “threats to validity” of any study. A example of a threat could be the failure to recognize more than one active ingredient at work. Or the tendency for subjects to taylor their response based on their gues at what the researcher wants to hear.
If even one of these threats has not been accounted for, the study comes into question. More than that? Well, then journalists like me start attaching words like “shoddy” to the research. The whole list is well worth a read, but let’s focus on the first and most well known: “Improvement from expectation of improvement,” otherwise called placebo.
This is a complicated question. Obviously, there wasn’t a subgroup of subjects who thought they were playing with a dolphin, but were actually playing with a sugar pill. This is especially important when you consider the nature of the therapy. Placebo researchers have long known that an important aspect of the placebo effect is how complicated the procedure is. One researcher calls it the “theater” of medicine. In a drug trial, regardless of which pill you get, there is a great fuss made over you – taking and monitoring your vitals, for instance. This fuss, researchers think, adds to the power of placebos. This may be the same reason that injections are more effective than pills. So what is a bigger theater than swimming in a pool with a dolphin? Given the attention to this special event, it’s hard to imagine a better breeding ground for unwanted placebo effects.
The second interesting point to make with these studies is the temporary nature of the improvement. It’s not clear in these studies that there is a lasting improvement to the cognitive abilities of the patients. This is a classic placebo characteristic. No matter what the symptom or bizarre reaction reported as a placebo effect, it is almost always temporary.
So how could we settle once and for all whether playing with dolphins is good for your health? Well, we would need to set up an experiment with some kind of placebo control. Which brings to mind the next question “What would a placebo dolphin even look like?” It turns out, and I am not kidding about this, that there is one in the works — kind of. A group called Virtual Dolphin Therapy in Southern California places patients on a waterbed with a video of dolphins swimming, creating the illusion of swimming with dolphins. According to their promotion materials, results have been just as good as work with live dolphins.
Which may answer our question right there.
Photo Credit: Stephen Gonzalez, via Flickr
 This morning I woke up, had breakfast, and, as I always do, had a cup of tea. I find it wakes me up and improves my performance for the morning’s work.
Or does it?
According to a study out of the University of California, San Diego, it may do just the opposite. The study compared three groups of people who had each use a different strategy to beat the midday doldrums. One group took a nap of up to 90 minutes, another had a caffeine pill and another took a dummy pill.
It showed that people who had caffeine saw a spike in alertness, but didn’t necessarily improve for memory or motor learning. In fact, subjects’ ability to learn new tasks actually tanked.The best performance, by and large, came from people who took a few moments out to take a nap.
But the real interesting part of this study was the control group. That is, one group was given a placebo caffeine pill and told it was the real thing. While these people did not perform as well as the group that took naps, they did perform better than the group actually taking caffeine.
   This is in keeping with several other studies lately that show that people who drink caffeine decline in their ability to do tasks at the same time that their opinion of that ability goes up. Performance down, opinion of that performance up.
When one takes a closer look at caffeine, they find that one of its primary pathways involves our old friend dopamine. That the same dopamine that is involved with heroin use as well as depression, and pain reduction. Not surprisingly, these are all processes heavily affected by placebo effects.
So let me boil this down for you. According to this study, there are three ways to pep myself up when I have an important job to do but am feeling drowsy. The worst would be to have a cup of coffee. The best would be to take a short nap. But barring that, the other sensible option would be to have my wife switch the coffee with decaf without my knowing. Then I could experience the joys of a placebo pick-me-up without the negative effects on my performance.
Photo Credit: David Morris, via Flickr
 A new study suggests that while placebos may have a powerful effect on those getting treatment, it may have the strongest effect on people not sure if they got it or not.
The study was performed on 35 patients undergoing therapy for Parkinson’s Disease. All of the patients received placebo pills, but some were told they had a 25 percent chance of getting their normal medication. Others were told 50 percent, 75 percent, and 100 percent. Oddly, the group that thought they had a 75 percent chance of getting the drug were the ones most effected by the placebo effect.
So what does this mean? Well, scientists have known for a long time that Parkinson Disease is tightly linked to dopamine and placebos. In fact, Parkinson’s patient appear to be abnormally susceptible to the mysterious effect. But what this study seems to show is that placebo responses are not uniform. That is, the way in which they are presented to the patient play a big role in how they effect them.
In this case, the patients were accustomed to the drugs, so they knew what to expect when they received them. Just like with Pavlov and his dog, there may have even been some level of trained response on the part of the patient – which is in itself a totally different kind of placebo response. However, with just a 50 percent chance of getting the real drug, the patients did not apparently think they were likely enough to get the drug in order to have a response. I guess that means on a fundamental level, we are all kind of pessimists at heart.
However, when their chances were better than even that they were receiving an active drug, their body went ahead and gave them a placebo response. As always, I won’t read too much into such a small study, but it brings to mind an interesting question. In a drug trial for, say, a new pain medication, most subjects think their chances of getting a placebo are about even. What would happen if they were higher? What if patients knew they had a one in three chance of getting the sugar pill and felt more confident they were getting the “real” thing? Would the placebo effect be stronger? Would the pain drug therefore be weaker?
 A new study in the New England Journal of Medicine takes aim at an immensely popular knee surgery performed on thousands of active people per year.
The surgery in question is for a torn ACL, the hefty ligament that connects your upper and lower leg. According to Gretchen Reynolds at the New York Times, one in every 556 active people will tear an ACL at some time in their lives.
The study looked at active people with knee injuries and compared those who got surgery and physical therapy with those who just got the physical therapy. With 121 participants total, let’s call this a medium sized study. Not a black diamond (to borrow a skiing metaphor), but not some dinky little green triangle bunny slope of a study either.
Amazingly, the people who got the physical therapy did almost exactly as well as those who also got the surgery. The study is reminiscent of a now-famous 2002 study that looked at a a different knee surgery. It found that people who got the surgery were just as likely to recover as those who actually got a fake surgery (as in, the surgeon just cut the knee and then closed it up without doing anything).
This is not to say that surgery is somehow not a good idea. However, a new surical procedure does not have to clear the same steep hurdles as, say, a new drug does. Meaning that it does not have to succeed in a double blind test toe-to-toe with the placebo effect.
One last interesting note about this story. So as not to be unfair, the researchers offered the surgery to the control group after the trial was done. And you know what? A healthy chunk still went for it, even though their group had recovered just as well as the others. Why the hell would anyone sign up for more surgery and, of course, more physical therapy, when their own study shows it may not do any good? I would be curious to know how many of the people who decided to get the extra surgery had already reported a good recovery.
 Ben Goldacre gives what might be the most succinct, Ritalin-infused, hilarious summary of the modern placebo effect a little while back at Nerdstock. Enjoy!
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Here’s a heartwarming picture for you. A small autistic child, totally cut off from the surrounding world is brought to a sunny Florida marine park. He fiddles with his backpack straps and refuses to acknowledge anyone around him. He’s then wet-suited up and tossed in a pool with a live dolphin, who proceeds to swim over and check him out and then gives him a ride on his back on command from the trainer.
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