The placebo effect refers to the phenomenon that patients unknowingly take fake drugs that have no effect at all, but can get the same or even better effect as the real drug. The placebo effect is supported by many clinical studies. One explanation for this phenomenon is that people's expectations for the future will change the physiological state of the brain, which in turn causes physiological changes in the whole body.
The statement 'Placebo has no effect on Alzheimer's patients who have lost the ability to anticipate the future' does not support the above explanation.