Une version consciente de l'effet placebo?

https://fr.wikipedia.org/wiki/Effet_Hawthorne

http://home.uchicago.edu/~jlist/papers/Was%20There%20Really%20a%20Hawthorne%20Effect%20at%20the%20Hawthorne%20Plant_An%20Analysis%20of%20the%20Original%20Illumination%20Experiments.pdf