%0 Journal Article
%A Llamas Cornejo, Ichasus
%A Peterzell, David H.
%A Serrano Pedraza, Ignacio
%T Temporal mechanisms in frontoparallel stereomotion revealed by individual differences analysis
%D 2024
%@ 0953-816X
%U https://hdl.handle.net/20.500.14352/116966
%X Masking experiments, using vertical and horizontal sinusoidal depth corrugations,have suggested the existence of more than two spatial-frequency disparitymechanisms. This result was confirmed through an individual differencesapproach. Here, using factor analytic techniques, we want to investigate theexistence of independent temporal mechanisms in frontoparallel stereoscopic(cyclopean) motion. To construct stereomotion, we used sinusoidal depthcorrugations obtained with dynamic random-dot stereograms. Thus, no luminancemotion was present monocularly. We measured disparity thresholds fordrifting vertical (up-down) and horizontal (left-right) sinusoidal corrugationsof 0.4 cyc/deg at 0.25, 0.5, 1, 2, 4, 6, and 8 Hz. In total, we tested 34 participants.Results showed a small orientation anisotropy with lower thresholds for horizontalcorrugations. Disparity thresholds as a function of temporal frequencywere almost constant from 0.25 up to 1 Hz, and then they increased monotonically.Principal component analysis uncovered two significant factors forvertical and two for horizontal corrugations. Varimax rotation showed thatone factor loaded from 0.25 to 1–2 Hz and a second factor from 2 to 4 to 8 Hz.Direct Oblimin rotation indicated a moderate intercorrelation of both factors.Our results suggest the possible existence of two somewhat interdependenttemporal mechanisms involved in frontoparallel stereomotion.
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