Beliefs and information can activate neural circuits in the prefrontal cortex, which then signal deeper brain areas like the hypothalamus to induce physiological changes.

“except expectation of what the machine is doing well that has the greatest placebo effect of all so for some reason as the level of invasiveness or the let's just say the complexity of a given treatment is increased well then the magnitude of the placebo effect is also increased and what this tells us is that the human brain has come to associate level of invasiveness level of complexity of a given treatment or machine to equate to bigger outcomes and in some sense that's completely logical but again we have to remember in absolutely zero of these conditions whether or not it's a tablet a capsule an injection or a medical device is there anything being done to these human subjects that impacts a specific biological function except one and that one again is the activation of specific neural circuits in the prefrontal cortex that then are able to communicate with other areas of the brain and body through Bonafide biological mechanisms of neurotransmitter release and electrical activity in neurons this is what the brain does and of course the prefrontal cortex being part of the brain those are the mechanisms it employs to change the activity of hormone relasing glands to change the activity of other neurons in other words the belief effects the expectations are real they are having effects through true biological circuitry it's just that the pills and the treatments and the machines are not doing anything specific at all except activating expectation”