A double-slit optical system was used to test the possible role of consciousness in the collapse of the quantum wavefunction. Each test session consisted of 40 counterbalanced attention-toward and attention-away epochs, and data was contributed by 137 people in six experiments, involving a total of 250 test sessions. The results appear to be consistent with a consciousness-related interpretation of the quantum measurement problem.
Previously reported experiments suggested that interference patterns generated by a double-slit optical system were perturbed by a psychophysical (i.e., mind–matter) interaction. Three new experiments were conducted to further investigate this phenomenon. The first study consisted of 50 half-hour test sessions where participants concentrated their attention-toward or -away from a double-slit system located 3 meters away.