Temporal crowding and its interplay with spatial crowding

Abstract

Spatial crowding refers to impaired target identification when the target is surrounded by other stimuli in space temporal crowding refers to impaired target identification when the target is surrounded by other stimuli in time previously, when spatial and temporal crowding were measured in the fovea they were interrelated with amblyopic observers but almost absent with normal observers bonneh, sagi, & polat, 2007. In the current study we examined whether reliable temporal crowding can be found for normal observers with peripheral presentation 9° of eccentricity, and whether similar relations between temporal and spatial crowding will emerge to that end, we presented a sequence of three displays separated by a varying interstimulus interval (ISI). Each display included either one letter : experiments 1a ,: 1b ,: 1c or three letters separated by a varying interletter spacing: Experiments 2a ,: 2b). One of these displays included an oriented T. Observers indicated the T's orientation. As expected, we found spatial crowding: accuracy improved as the interletter spacing increased. Critically, we also found temporal crowding: in all experiments accuracy increased as the ISI increased, even when only stimulus-onset asynchronies (SOAs) larger than 150 ms were included, ensuring this effect does not reflect mere ordinary masking. Thus, with peripheral presentation, temporal crowding also emerged for normal observers. However, only a weak interaction between temporal and spatial crowding was found.

Perception and decision mechanisms involved in average estimation of spatiotemporal ensembles

“…Another notable discrepancy is that the increase of impact near the last frame, which characterizes the recency effect, appears too steep in human data as compared to the model prediction. This might be partly owing to the visible persistence of the last frame 53 , backward masking of the previous frames by the last frame 54 , or temporal crowding, in rapid presentation 55,56 . However, it is doubtful that such perceptual effects can entirely explain our results because our subsequent experiments confirmed that such a steep recency effect is still robustly observed even if frame rate was reduced to as slow as 10 Hz and the average orientation of every frame (100 ms) was perceived very clearly.…”

Letter and symbol identification: No evidence for letter-specific crowding mechanisms

“…This phenomenon, known as visual crowding, has been extensively studied in the last two decades. Crowding is thought to be a major limiting factor of reading and of spatial vision although the precise nature of its underlying mechanisms is still strongly debated (He, Cavanagh, & Intriligator, 1996;Herzog, Sayim, Chicherov, & Manassi, 2015;Intriligator & Cavanagh, 2001;Pelli, Palomares, & Majaj, 2004;Pelli & Tillman, 2008;Saarela, Sayim, Westheimer, & Herzog, 2009;Strasburger, Harvey, & Rentschler, 1991;Strasburger & Malania, 2013;Tyler & Likova, 2007;Wolford, 1975;Yeshurun & Rashal, 2010;Yeshurun, Rashal, & Tkacz-Domb, 2015). Some recent reviews show the difficulty of providing a clear-cut understanding of crowding (Levi, 2008;Strasburger, Rentschler, & Jüttner, 2011).…”

The role of Peripheral Vision in the Flashed Face Distortion Effect

“…Visual crowding occurs not only for stimuli that are in close spatial proximity, but also for stimuli that are temporally close to one another. Yeshurun, Rashal and Tkacz-Domb (2015) investigated temporal crowding for letters by varying presentation rate.…”