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Attentional selection of noncontiguous locations: The spotlight is only transiently “split"

Dubois, Julien and Hamker, Fred H. and VanRullen, Rufin (2009) Attentional selection of noncontiguous locations: The spotlight is only transiently “split". Journal of Vision, 9 (5). Art. No. 3. ISSN 1534-7362. doi:10.1167/9.5.3.

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It is still a matter of debate whether observers can attend simultaneously to more than one location. Using essentially the same paradigm as was used previously by N. P. Bichot, K. R. Cave, and H. Pashler (1999), we demonstrate that their finding of an attentional “split” between separate target locations only reflects the early phase of attentional selection. Our subjects were asked to compare the shapes (circle or square) of 2 oddly colored targets within an array of 8 stimuli. After a varying stimulus onset asynchrony (SOA), 8 letters were flashed at the previous stimulus locations, followed by a mask. For a given SOA, the performance of subjects at reporting letters in each location was taken to reflect the distribution of spatial attention. In particular, by considering the proportion of trials in which none or both of the target letters were reported, we were able to infer the respective amount of attention allocated to each target without knowing, on a trial-by-trial basis which location (if any) was receiving the most attentional resources. Our results show that for SOAs under 100–150 ms, attention can be equally split between the two targets, a conclusion compatible with previous reports. However, with longer SOAs, this attentional division can no longer be sustained and attention ultimately settles at the location of one single stimulus.

Item Type:Article
Related URLs:
URLURL TypeDescription
Dubois, Julien0000-0002-3029-173X
VanRullen, Rufin0000-0002-3611-7716
Additional Information:© 2009 ARVO. Received September 23, 2008; published May 8, 2009. Part of this work has been presented earlier in abstract form (Hamker, F. H., & VanRullen, R. (2002). The time course of attentional selection among competing locations [Abstract]. Journal of Vision, 2(7):7, 7a, This work was supported by the German Science Foundation (DFG HA2630/2-1) and the Federal Ministry of Education and Research Grant (BMBF 01GW0653), the CNRS (Grant CNRS-USA), the ANR (06JCJC-0154), the Fyssen Foundation, and the European Science Foundation (EURYI). We wish to acknowledge Kyle Cave and an anonymous referee for helpful advice and suggestions and Christof Koch for his continued support.
Group:Koch Laboratory (KLAB)
Funding AgencyGrant Number
Deutsche Forschungsgemeinschaft (DFG)DFGHA2630/2-1
Bundesministerium für Bildung und Forschung (BMBF)BMBF 01GW0653
Centre National de la Recherche Scientifique (CNRS)UNSPECIFIED
Agence Nationale pour la Recherche (ANR)06JCJC-0154
Fyssen FoundationUNSPECIFIED
European Science FoundationUNSPECIFIED
Subject Keywords:attention, divided spotlight, time course, premotor theory
Issue or Number:5
Record Number:CaltechAUTHORS:20090821-133126021
Persistent URL:
Official Citation:Dubois, J., Hamker, F. H., & VanRullen, R. (2009). Attentional selection of noncontiguous locations: The spotlight is only transiently “split” Journal of Vision, 9(5):3, 1-11,, doi:10.1167/9.5.3.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:15238
Deposited On:24 Aug 2009 17:25
Last Modified:08 Nov 2021 23:17

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