Can a Human See a Single Photon? (1996)
There is a well known (I heard about it in the late 70&#x27;s) problem with these types of experiments.  The assumption is that if the subjects&#x27; &quot;guesses&quot; statistically match the assumed hit rate of photons then there must be a cause and effect.  This experiments seems to make no attempt to eliminate the possibility that this is completely random.