Long ago (which means I may not recall the story correctly, and I can’t link to it or otherwise verify its veracity), I was told about a study that examined the placebo effect directly. Rather than breaking the test subjects into three groups (control, placebo, actual drug), it was broken into four (control, placebo but they didn’t necessarily know it, placebo but they told them it was placebo, actual drug). What they found is that the placebo group did do better than the control group, and it didn’t really matter whether they knew the medicine was actually just a sugar pill or not: those who received care did better than those who didn’t. (I don’t recall if the medication worked.)
The study’s authors speculated that there was something about official medical care, the trappings of lab coats and clipboards and stethoscopes and such, that for some reason inspired healing that didn’t happen to people who didn’t receive this care.
I have a theory. I have never heard anyone else say this theory, so it’s possible it’s entirely my own, and therefore possible I’m entirely full of shit. But I theorize that, in a social species, always getting better no matter the cost isn’t the most adaptive way to respond to illness or injury. It matters whether the cost to the larger community is going to be greater than or less than what will be gained after the individual recovers. If the individual is only of marginal value, better to just die quickly rather than consume resources attempting to get better. If the individual is of high value, better to hang in there and get better.
The community signals this relative value through the administration of care. Of course, it is helpful if the specifics of care have additional medical value. But the mere fact that an important person’s time (a doctor’s, or a shaman’s, or whoever’s) is being consumed to help this person get better signals to the body that the community would prefer they recover.
This isn’t a memetic thing, and so the mind need not be fooled. So long as the emotional content is correct, the signal will be sent, and a switch will be flipped that induces the recipient of care to “try harder” to get better, rather than die quickly and get out of the way.
But as I said, this is just my personal theory, which is based upon a study that may not actually have ever been done, at least as I remember it.
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