The first serious attempt at control and analysis of apparent movement was made by Exner in 1875. At first he believed it to be the result of 'diffusion circles' emanating from each of the retinal points stimulated, but when the phenomenon was elicited by stimulating a point in each retina he advanced as his explanation a tendency of the observer to see motion whenever the stimuli received made such an appearance possible. Stratton, in 1902 and 1911, reported on his investigations and gave an explanation in terms of a conscious organization of sensations. He spoke of a 'relational activity of the mind' which interprets the incoming sensations and gives to them the meaning of movement.
Proceedings of the Iowa Academy of Science
©1948 Iowa Academy of Science, Inc.
Wingett, M. E. and Haner, C. F.
"Previous Learning as a Factor Influencing Perception of the Phi-Phenomenon,"
Proceedings of the Iowa Academy of Science, 55(1), 339-345.
Available at: https://scholarworks.uni.edu/pias/vol55/iss1/48