Placebos trigger an opioid hit in the brain

[emad]

Placebos trigger an opioid hit in the brain
22:00 23 August 2005

The Journal of Neuroscience

It seems that placebos have a real physical, not imagined, effect – activating the production of chemicals in the brain that relieve pain, a new study suggests.

Placebos are treatments that use substances which have no active ingredient. But if people are told that what they are being given contains an active painkiller, for example, they often feel less pain – an effect that has normally been considered psychological.

Recent studies, though, suggest otherwise. For example, when a placebo was secretly mixed with a drug that blocks endorphins – the body’s natural painkillers – there was no placebo effect, showing that endorphins are involved in the placebo painkiller process (New Scientist print edition, 26 May 2001, p 34).

Now Jon-Kar Zubieta’s team at the University of Michigan at Ann Arbor, US, has confirmed that placebos relieve pain by boosting the release of endorphins.
http://www.newscientist.com/article.ns?id=dn7892

[HuckleB]

1. I guess I have to say, duh!

You don't get a "psychological" change without a physiological change -- the mind does what it does via biochemistry, whether we're talking about thought, dreams, or pain relief.

[htuttle]

2. You're right

If you're talking about the brain (which is where pain exists, after all), I'm not sure I'd make a bright line between 'psychological' and 'physiological' anyway.

Is a "thought" or "sensation" psychological or physiological in nature? Seems like our Cartesian mind/body dualism breaks down when dealing with the brain itself, you know?

It's interesting to note that even many strict materialists seem to have trouble assimilating the idea that our minds are entirely the product of physiological processes, and not some ethreal, non-material 'thought stuff' that exists apart from our bodies, ie., I'm not some disembodied 'mind' driving this body around -- I AM this body.

Sometimes, it can be very confusing living as a cooperative entity of some 50-100 trillion individual lifeforms.

[salvorhardin]

3. I don't see where you need to posit a paranormal (nonmaterial) component

You're just talking about the software/hardware distinction as it applies to the brain. Because of the way our brain is constructed, a software change also changes the hardware. For instance, in learning (transferring a memory from short term to long term storage), a small region of your brain is physically changed. The big question is to what extent the act of just using our brains can change them. Of course, very little changes. You will not be able to think your way out of damage to Broca's area but you may be able to think yourself out of depression.

The suggestion here is that the act of thinking about pain relief (which involves recalling memories about how it felt before -- an expectation) can bring at least some relief from pain. This is not entirely surprising. When we remember something the information gets routed through the same areas of the brain we used to acquire the information. If you remember someone's face, the visual processing areas of your brain are activated. I would expect that a similar mechanism is at play here.

[htuttle]

4. That's the way computer hardware/software is constructed, too

There are as many 'hardware' changes in a computer chip when it's running software as there are in the brain when you think. The changes in a computer chip are just very, very small (ie., electron-sized). Software, like the mind, is a pattern of hardware behavior.

What I find ironic, and what I was referring to in my reply, are those who profess to be strict materialists, yet deny that the processes of the mind can have any effect on the health of the physical body. What do they imagine the mind is, then?

[salvorhardin]

5. That's not true

at least that's not true for this materialist. I know of no skeptic that denies that processes of the brain can have an effect on overall health. Despression would be one such example. The placebo effect would be another.

Not to speak for the other skeptics here, but for me the problem comes in when a paranormal (paraphysical if you prefer) component is brought into the picture. Our brains are made out the same physical stuff as the rest of the world. There's no reason to suppose that they somehow don't follow the same mechanisms that govern all the rest of the matter in the universe. There's also a general confusion as to the extent which processes in the brain can have an effect on general health. As I said before, you are not going to think yourself out of damage to Broca's area and you're not going to think yourself a new leg if one happens to have been severed or amputated. Actually that is part of a bigger problem of people who believe that they can "will" something to happen whether to their body or to something else.

[htuttle]

6. If you can't will your body to do something, how were you typing that?

I can will my body to do all sorts of things. I can walk, I can talk, I can jump up and down. Sure, that's all voluntary nervous system stuff. We know where the wires are.

No, I do not think that a person can repair damage to Broca's area or think themselves a new leg -- at least nobody has ever done so to my knowledge.

But framing the reason *why* nobody ever has done so as 'not being able to will something to happen to their body' suggests mind/body dualism. My mind is not apart from my body, cutoff from any physical effect. I'd frame the reason in terms of 'there's no known mechanism for that to happen, and it never has to anyone's knowledge'.

So it's not because your mind can't will your body around that you can't regenerate a missing leg. It's because your body doesn't have a way of doing that...that we know of...without some sort of stem-cell/cloning procedure we haven't invented yet.