Effects of visual blur and contrast on spatial and temporal precision in manual interception

Abstract

The visual system is said to be especially sensitive towards spatial but lesser so towards temporal information. To test this, in two experiments, we systematically reduced the acuity and contrast of a visual stimulus and examined the impact on spatial and temporal precision (and accuracy) in a manual interception task. In Experiment 1, we blurred a virtual, to-be-intercepted moving circle (ball). Participants were asked to indicate (i.e., finger tap) on a touchscreen where and when the virtual ball crossed a ground line. As a measure of spatial and temporal accuracy and precision, we analyzed the constant and variable errors, respectively. With increasing blur, the spatial and temporal variable error, as well as the spatial constant error increased, while the temporal constant error decreased. Because in the first experiment, blur was potentially confounded with contrast, in Experiment 2, we re-ran the experiment with one difference: instead of blur, we included five levels of contrast matched to the blur levels. We found no systematic effects of contrast. Our findings confirm that blurring vision decreases spatial precision and accuracy and that the effects were not mediated by concomitant changes in contrast. However, blurring vision also affected temporal precision and accuracy, thereby questioning the generalizability of the theoretical predictions to the applied interception task.

Tau and kappa in interception – how perceptual spatiotemporal interrelations affect movements

“…This resulted in 0.02-1.85% data exclusion in Experiments 1 and 2 (see Table S1 in the Online Supplement for further details). To evaluate the effect of the context variable on the primary task, linear mixed models were run, with either the spatial response or the temporal response as dependent variable (Schroeger et al, 2021;Tolentino-Castro et al, 2021). For both models the spatial interval, temporal interval, and blur/volume as well as their interactions were included as fixed and random effects for participants and random intercepts were modeled.…”

“…We used an interception setup similar to the ones reported in two recent studies by Schroeger et al (2021) and Tolentino-Castro et al (2021). Participants performed an interception task on a 43in.…”

“…A total of 43 participants (17 male, M Age = 24.2 years, SD Age = 3.3 years, sample size similar to previous studies on interception, e.g., Schroeger et al, 2021) took part in the experiment. All provided informed consent prior to participation.…”

“…In total 40 participants (19 male, M Age = 24.2 years, SD Age = 3.3 years; sample size similar to previous studies on interception, e.g., Schroeger et al, 2021) who did not enroll in Experiment 1 took part in the second experiment. Of the initially 45 collected data sets, five were excluded from the analysis because participants did not fulfil the vision requirements (3) or due to technical problems with the eye-tracking measurement (2).…”

The Effect of Context Switching, Focal Switching Distance, Binocular and Monocular Viewing, and Transient Focal Blur on Human Performance in Optical See-Through Augmented Reality

“…Many studies have explored how different amounts of blur impact the performance of visual search tasks. These show that increasing blur reduces performance [38,45]. However, the authors could not find previous research that has discussed the effects of transient focal blur, which happens within the short time frame of reaccommodation to a new focal distance.…”