A new spin on the placebo effect

[JLam]

Interesting things coming from Columbia University.

From Newsweek:

Doctors have long thought the placebo effect was psychological.Now scientists are amassing the first direct evidence that the placebo effect actually is physical, and that expecting benefit can trigger the same neurological pathways of healing as real medication does. Among them:

• University of Michigan scientists injected the jaws of healthy young men with salt water to cause painful pressure, while PET scans measured the impact in their brains. During one scan, the men were told they were getting a pain reliever, actually a placebo.

Their brains immediately released more endorphins — chemicals that act as natural painkillers by blocking the transmission of pain signals between nerve cells — and the men felt better. To return to pre-placebo pain levels, scientists had to increase the salt-water pressure.
“Our brain really is on drugs when we get a placebo,” says co-researcher Christian Stohler, now at the University of Maryland. More remarkable, some especially strong placebo responders suggest “many brains can actually stimulate that (pain-relief) system more.”

Obviously it's all preliminary stuff, but interesting nonetheless.

 

[TobiasTheViking]

Interesting things coming from Columbia University.

From Newsweek:



Obviously it's all preliminary stuff, but interesting nonetheless.

I wouldn't really claim that that was a new spin on the placebo effect.

I have always heard the placebo effect being descriped as people believing they are getting something that helps them. Thus they relax a bit, and releases some endorphines.

The release of endorphines can come from the mind(think about falling in love, releases endorphines as well).

 

[JLam]

It's just that this is the first time that there's been direct evidence that the placebo effect is more than psychological. Neat stuff.

 

[Beth]

It's just that this is the first time that there's been direct evidence that the placebo effect is more than psychological. Neat stuff.

This was interesting. Thanks for posting it.

I don't know that I'd say it is more than psychological though. I see it as a more detailed description of how the psychology works. I guess it depends on how you define psychological. I tend to include neural changes as part of psychology, but perhaps that's sloppy thinking on my part.

 

[drkitten]

This was interesting. Thanks for posting it.

I don't know that I'd say it is more than psychological though. I see it as a more detailed description of how the psychology works. I guess it depends on how you define psychological. I tend to include neural changes as part of psychology, but perhaps that's sloppy thinking on my part.

It's not sloppy thinking, but you are perhaps missing some of the significance of this finding. Certainly neurochemical changes are "part of" psychology, but they're a different part of psychology than the emotional aspects that aren't accompanied by neurochemical changes. In terms of significance, we could think about the parallel cases of the discovery of the specific neurotransmitters involved in depression. Many cases of depression are now known to be related to chemical imbalances, which makes them much more treatable than before. Can we do the same thing with chronic pain?

If this finding holds up (I see no reason why it shoudn't, but newly released research should always be taken with a certain degree of suspicion), then there's an underlying neurochemical basic for at least part of the placebo effect, which suggests a number of interesting practical changes to pain management. Just as a for-instance -- can we teach patients to release these kind of endorphins themselves, insteadof having to pay substantial sums to quacks for their dose of sugar pills?

 

[hammegk]

... Just as a for-instance -- can we teach patients to release these kind of endorphins themselves, instead of having to pay substantial sums to quacks for their dose of sugar pills?

Zocor? Viagra? Vioxx? Zoloft? Aspirin?

 

[Beth]

It's not sloppy thinking, but you are perhaps missing some of the significance of this finding. Certainly neurochemical changes are "part of" psychology, but they're a different part of psychology than the emotional aspects that aren't accompanied by neurochemical changes.

Sorry to be so dense, but what aspects of psychology - emotional or otherwise - are not accompanyied by neurochemical changes? I can understand that we don't know or understand all of them, but I would have thought that all psychological changes would be accompanied by neurochemcal changes.

In terms of significance, we could think about the parallel cases of the discovery of the specific neurotransmitters involved in depression. Many cases of depression are now known to be related to chemical imbalances, which makes them much more treatable than before. Can we do the same thing with chronic pain?

If this finding holds up (I see no reason why it shoudn't, but newly released research should always be taken with a certain degree of suspicion), then there's an underlying neurochemical basic for at least part of the placebo effect, which suggests a number of interesting practical changes to pain management. Just as a for-instance -- can we teach patients to release these kind of endorphins themselves, insteadof having to pay substantial sums to quacks for their dose of sugar pills?

I've heard of some good reports regarding biofeedback for pain management, but it was several years ago. I don't know if that research came to naught or if it's being put to use. Is that the path you would envision further research in this area going?

 

[Mojo]

Zocor? Viagra? Vioxx? Zoloft? Aspirin?

Panexa!

 

[Rolfe]

I have some doubts that this sort of effect contributes much to the "placebo effect" as described for SCAM treatments. This is partly based on the fact that it seems even easier to get these SCAM effects in animals than in human patients. Now, if the effect was real, as this suggests, I don't see how you can induce it in a dog by making it swallow a sugar pill. On the other hand, putting another observer between the patient and the therapist seems on the face of it a very good way to increase the observer bias that so much of this seems to consist of.

Rolfe.

 

[Melendwyr]

Doctors have long thought the placebo effect was psychological.Now scientists are amassing the first direct evidence that the placebo effect actually is physical,

Idiots! What did they think the mind was made out of - fairy dust and essence of moonbeams?!

 

[Mojo]

Now, if the effect was real, as this suggests, I don't see how you can induce it in a dog by making it swallow a sugar pill.

How about if you patted it on the head and said "nice doggie" first?

 

[hammegk]

"all it takes is love, love.... love is all you need"

 

[drkitten]

Sorry to be so dense, but what aspects of psychology - emotional or otherwise - are not accompanyied by neurochemical changes?

I don't think that any aspects of psychology are known not to be accompanied by neurochemical changes, but huge amounts of psychology are not known to be accompanied by neurochemical changes.

I can understand that we don't know or understand all of them, but I would have thought that all psychological changes would be accompanied by neurochemcal changes.

It's a directness issue. Rolfe's example of homeopathic veterinary medicine is a good one -- if you can persuade the pet owner that their pet is feeling better by giving it sugar pills, what's going on in the pet owner's head? We're not (yet) at the stage where we can trace the neurochemistry of contentful beliefs -- if there's a neurochemical basis underlying my belief that "Fluffy is feeling better," it doesn't appear to be any different in kind or complexity from any other statement you might be able to persuade me to believe. "Prague is the most beautiful city in the world." "Lasagna tastes better if made with a vegetarian sauce than if made with a meat sauce." "The best pinot noir in the world comes from the Willamette Valley in Oregon, USA."

I can't even imagine trying to develop a pill that would cause someone to believe that Prague is more beautiful than Sydney. There's not a single neuron or single chemical that "represents" that information (to the best of our knowledge).

So we can compare Rolfe's patients to human patients. Rolfe's patients believe that their dogs feel better because -- well, because they believe their dogs feel better. As best we know, it's a propositional belief, with all that complexity. These humans believe that they (the humans) feel better because they do feel better -- it's not a propositional belief, but a simple biochemical fact.

Again, think of the treatment for depression. It's not as simple (or as complex) as "I'm not happy because I'm not happy." Instead, it becomes "I'm not happy because I have the wrong set of chemicals in my brain, and I become happy when the chemicals get balanced."

I've heard of some good reports regarding biofeedback for pain management, but it was several years ago. I don't know if that research came to naught or if it's being put to use. Is that the path you would envision further research in this area going?

That's a definite possibility. In particular, if we actually have a way to measure the effectiveness of the "placebo effect," we can give more meaningful feedback....

 

[Starthinker]

There was an episode of M*A*S*H once where they ran out of morphine and started giving the patients salt water and no one complained.

 

[Melendwyr]

I don't think that any aspects of psychology are known not to be accompanied by neurochemical changes, but huge amounts of psychology are not known to be accompanied by neurochemical changes.

Well, to be very pedantic, this is false. All neuronal signaling is done through chemicals, after all.

Whether any particular example of information processing requires widescale changes in brain chemistry is not known. (Probably not.)

We're not (yet) at the stage where we can trace the neurochemistry of contentful beliefs -- if there's a neurochemical basis underlying my belief that "Fluffy is feeling better,"

We can be fairly certain that this is not the case.

Again, think of the treatment for depression. It's not as simple (or as complex) as "I'm not happy because I'm not happy." Instead, it becomes "I'm not happy because I have the wrong set of chemicals in my brain, and I become happy when the chemicals get balanced."

Bull. The brain is spectacularly good at adjusting to changes in available neurotransmitters - that's what's responsible for the nightmare of addiction, for example.

There are a few cases where the brain can no longer adjust - Parkinson's Disease, for example - but that involves massive loss of the relevant neuronal production mechanisms before there are clear symptoms.

 

[Mojo]

It's a directness issue. Rolfe's example of homeopathic veterinary medicine is a good one -- if you can persuade the pet owner that their pet is feeling better by giving it sugar pills, what's going on in the pet owner's head? We're not (yet) at the stage where we can trace the neurochemistry of contentful beliefs -- if there's a neurochemical basis underlying my belief that "Fluffy is feeling better," it doesn't appear to be any different in kind or complexity from any other statement you might be able to persuade me to believe. "Prague is the most beautiful city in the world." "Lasagna tastes better if made with a vegetarian sauce than if made with a meat sauce." "The best pinot noir in the world comes from the Willamette Valley in Oregon, USA."

I can't even imagine trying to develop a pill that would cause someone to believe that Prague is more beautiful than Sydney. There's not a single neuron or single chemical that "represents" that information (to the best of our knowledge).

Whether you can produce a pill to make someont belive that "Fluffy is feeling better" is irrelevant. What is being talked about is a combination of two effects: a sort of "placebo by proxy" effect, where the owner is told that the pill will make Fluffy better, and sees the vet being attentive to the animal, so that the placebo effect is actually working on the owner rather than the pet; and the power of suggestion, so that the owner interprets the animal's appearence and behaviour as indications that it is getting better, whether it actually is getting better or not.

If the mechanism for the placebo effect in fact works as suggested in the OP, it's quite possible that the placebo effect is working on the owner by causing the owner's brain to release endorphins so that they see their animal's condition through rose-tinted spectacles.

 

[drkitten]

Well, to be very pedantic, this is false. All neuronal signaling is done through chemicals, after all.

Really? When was dualism proven false? I must have missed the announcement coming from the Swedish Academy.

And you're contradicting yourself. If everything about the mind/brain is "done through chemicals after all, " then this must include propositional beliefs as well. So somewhere, there are neurochemical structures corresponding to the beliefs that "Fluffy is feeling better," that "peanut butter tastes good," and that "P < NP."

Bull. The brain is spectacularly good at adjusting to changes in available neurotransmitters - that's what's responsible for the nightmare of addiction, for example.

Um, bull yourself.

Read up on depression and neurotransmitters sometime. The link between neurotransmitters and depression is well-known.

In particular, Zoloft, Prozac, Paxil, etc., (the classic high-powered antidepressants) are a kind of drug sometimes called selective serotonin re-uptake inhibitor (SSRI). Many depressives -- not all, unfortunately -- have measurably low levels of the particular neurotransmitter serotonin. This keeps the synapse from working properly -- there's not enough serotonin in the synaptic gap to transmit signals and the receptor cell doesn't fire as it should. These drugs work by keeping neurons from (re)absorbing serononin from the synapses. With less serotonin inside the neurons, more of it is outside (in the synaptic gap, where it can work),. For more details, consult your local M.D. or Wikipedia.

Under normal circumstances, the human brain is remarkably resiliant. But one of the central findings of this line of research is that depressives' brains are not "normal circumstances." Depressives' brains do not work properly precisely because they don't handle serotonin (and other neurotransmitters) properly. THe brain of these depressives can't balance the chemicals properly, and as a result, the people feel unhappy. If you can artificially straighten out these chemicals (as above), then they improve.

 

[drkitten]

If the mechanism for the placebo effect in fact works as suggested in the OP, it's quite possible that the placebo effect is working on the owner by causing the owner's brain to release endorphins so that they see their animal's condition through rose-tinted spectacles.

Except that's not generally what endorphins do.

Endorphins are fairly well-established to be pain-killers, not hallucinogens. As in, they reduce my sensation of pain, but they don't generally cause me to believe things that are false.

There's an easy way of testing this. We know of lots of other CNS depressants that have vaguely similar effects to endorphins -- alcohol, for one. If the effect really were just causing the owner to see the world through rose-coloured beer goggles, then I could get a similar effect just by giving the owner a stiff drink and seeing if that duplicated the effect of giving sugar pills to Fluffy. I really doubt that those two treatments would be equivalently effective.

 

[Melendwyr]

Really? When was dualism proven false?

Dualism has nothing to do with it. The hypothesis that neurons communicated electrically was disproven as soon as the synaptic gap was first seen under the microscope.

And you're contradicting yourself. If everything about the mind/brain is "done through chemicals after all, " then this must include propositional beliefs as well.

Communication is accomplished by chemical signals. That does not equate to "everything". Learn to read, please.

So somewhere, there are neurochemical structures corresponding to the beliefs that "Fluffy is feeling better," that "peanut butter tastes good," and that "P < NP."

Nope.

Read up on depression and neurotransmitters sometime. The link between neurotransmitters and depression is well-known.

We cannot induce depression. We cannot show that depressed patients have similar dearths of neurotransmitters. We cannot even establish what a "functional" level is, considering how significantly healthy individuals' levels vary.

Many depressives -- not all, unfortunately -- have measurably low levels of the particular neurotransmitter serotonin.

Cause, or effect?

This keeps the synapse from working properly -- there's not enough serotonin in the synaptic gap to transmit signals and the receptor cell doesn't fire as it should.

The brain is very good at increasing the number of receptors to compensate. The cases where it cannot involve massive failure of neurotransmitter production mechaisms (like Parkinson's).

These drugs work by keeping neurons from (re)absorbing serononin from the synapses. With less serotonin inside the neurons, more of it is outside (in the synaptic gap, where it can work),.

If that were actually how those drugs functioned, then they would have their greatest effect soon after treatment begins, when the effect on neurotransmitters is greatest. However, the main antidepressant effect takes several weeks to several months to show up - after the brain has started to compensate for the changes.

Additionally: if the drugs somehow established "normal" conditions, why would the brain need to compensate at all? That's not what we see in cases of massive chronic pain and opiates.

Depressives' brains do not work properly precisely because they don't handle serotonin (and other neurotransmitters) properly.

Begging the question, and assuming facts not in evidence.

The brain of these depressives can't balance the chemicals properly

What do you actually mean, 'balance'? You can't demonstrate that there's a systematic problem with how serotonin is produced or regulated. You're assuming that there's a biochemical problem because the patients are depressed.

 

[Mojo]

Except that's not generally what endorphins do.

Endorphins are fairly well-established to be pain-killers, not hallucinogens. As in, they reduce my sensation of pain, but they don't generally cause me to believe things that are false.

I was under the impression that they also give a general feeling of well-being, as well as reducing pain. This might well make the owner feel more positive about the pet's condition.