Consciousness-related interactions in a double-slit optical interferometer

Motivated by a series of reported experiments and their controversial results, the present work investigated if volunteers could causally affect an optical double-slit system through mental efforts alone. The participants task alternated between intending the increase of the (real-time feedback informed) amount of light diffracted through a specific single slit and relaxing any intention effort. The 160 data sessions contributed by 127 volunteers revealed a statistically significant 6.37 sigma difference between the measurements performed in the intention versus the relax conditions (p = 1.89 × 10, es = 0.50 ± 0.08), while the 160 control sessions conducted without any present observer resulted in statistically equivalent samples (z = −0.04, p = 0.97, es = 0.00 ± 0.08). The results couldn’t be simply explained by environmental factors, hence supporting the previously claimed existence of a not yet mapped form of interaction between a conscious agent and a physical system.