Yes / When a target is flanked by distractors, it becomes more
difficult to identify. In the periphery, this crowding effect
extends over a wide range of target-flanker separations,
called the spatial extent of interaction (EoI). A recent
study showed that the EoI dramatically increases in size
for short presentation durations (Chung & Mansfield,
2009). Here we investigate this duration-EoI relation in
greater detail and show that (a) it holds even when
visibility of the unflanked target is equated for different
durations, (b) the function saturates for durations
shorter than 30 to 80 ms, and (c) the largest EoIs
represent a critical spacing greater than 50% of
eccentricity. We also investigated the effect of same or
different polarity for targets and flankers across different
presentation durations. We found that EoIs for target
and flankers having opposite polarity (one white, the
other black) show the same temporal pattern as for
same polarity stimuli, but are smaller at all durations by
29% to 44%. The observed saturation of the EoI for shortduration
stimuli suggests that crowding follows the locus
of temporal integration. Overall, the results constrain
theories that map crowding zones to fixed spatial
extents or to lateral connections of fixed length in the
cortex. / This study was supported by the ERC POSITION 324070 (PC) and a visiting professorship to Anglia Ruskin University from the Leverhulme Trust (HEB).
| Identifer | oai:union.ndltd.org:BRADFORD/oai:bradscholars.brad.ac.uk:10454/10481 |
| Date | 12 1900 |
| Creators | Tripathy, Srimant P., Cavanagh, P., Bedell, H.E. |
| Source Sets | Bradford Scholars |
| Language | English |
| Detected Language | English |
| Type | Article, Published version |
| Rights | © 2014 The Association for Research in Vision and Ophthalmology, Inc. This work is licensed under a Creative Commons Attribution-Non-Commercial–No Derivatives License. |
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