[Neuroscience] Re: The Placebo Effect on the Rat Immune Response
James Michael Howard
(by jmhoward from anthropogeny.com)
Sun Dec 9 12:17:46 EST 2007
On Sun, 9 Dec 2007 18:25:03 +1000, "John H." <johnh from goawayplease.com>
>In the space of 3 days I have read two books citing this experiment and it
>is baffling. Please don't try and wash it away with a rationalisation of the
>dumbass kind, it is very obvious to any honest clinician that a person's
>attitude can have a profound effect on disease progression. Nor is this
>spooky, the problem can be couched within a neuro-endocrine-immunological
>axis of understanding; though I admit that paradigm certainly cannot explain
>all that comes under the umbrella of the placebo effect. So it still might
>be spooky ...
>In this experiment the Bob Ader and Nick Cohen decided to see if the immune
>system could be trained to respond to a conditioned stimulus. The paired the
>sweet taste of saccharine wtih an anticancer drug that suppresses immune
>immune function, cyclophosphamide. They fed the drug and the saccharine to
>the rats over and over again. Each time the immunosuppressive drug was given
>the immune cell count went down. Then they took away the drug and just gave
>the saccharine alone. The immune cell count fell again. Before the
>conditioning process the saccharine had no impact on immune cell count.
>I cannot find a way to understand this. Yes the brain and immune systems do
>influence each other great deal but nothing in our current understanding can
>Now if the placebo effect is about suggestion then these are very clever
>rats. You might want to look up the Norman Cousins and Henry Beecher. Then
>you'll really get confused. (Those two instances I can offer a plausible
>explanation but this one has me stumped.)Why the placebo effect is ignored
>is beyond me. I suspect it simply doesn't fit into our current understanding
>so people wash it away with some dumbass explanation. This is what happened
>to Ader and Cohen, initially their results were treated with derision. If
>anyone knows if someone has come up with an explanation for this effect I
>sure would like to hear it.
It is my hypothesis (copyrighted, 1985) that the "fight or flight
mechanism" is controlled by the ratio of cortisol to DHEA. This is derived
from my principle hypothesis that DHEA was selected by evolution because it
optimizes replication and transcription of DNA. Therefore, all tissues are
positively affected by DHEA, including the nervous and immune sytems. This
caused me to consider the steroid production of the adrenal glands. DHEA
is the major steroid hormone of the adrenal glands. Since cortisol is the
second hormone in production and is known to cause negative effects,
especially in excessive amounts and prolonged exposure, I deduced
(hypothesis) that the ratio determines of these hormones produces the raio
of positive to negative effects of on the nervous system, including the
fight or flight mechanism. It is this consequences of fighting or fleeing
that determined the evolution of this mechanism.
If a negative stimulus is presented to an animal, the cortisol increases.
If this cortisol release is tied to a normally positive or neutral event,
these will produce the cortisol response. Cortisol is known to produce
negative effects on all systems. I suggest if the cortisol to DHEA ratio
is high, this occurs because the beneficial effects of DHEA are reduced.
As I stated above, I think DHEA positively affects all systems. Hence when
cortisol increases, and is connected to stimuli, then the nervous system
and immune system both respond to an increased cortisol to DHEA ratio
relatively at the same time.
Stimuli that may be connected with DHEA will increase the positive effects
of DHEA. If one anticipates that a stimulus will be positive, some
individuals may increase the DHEA to cortisol ratio and produce the
positive effects of the "placebo effect."
James Michael Howard
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