Deployment of spatial attention to words in central and peripheral vision

Abstract

Four perceptual identification experiments examined the influence of spatial cues on the recognition of words presented in central vision (with fixation on either the first or last letter of the target word) and in peripheral vision (displaced left or right of a central fixation point). Stimulus location had a strong effect on word identification accuracy in both central and peripheral vision, showing a strong right visual field superiority that did not depend on eccentricity. Valid spatial cues improved word identification for peripherally presented targets but were largely ineffective for centrally presented targets. Effects of spatial cuing interacted with visual field effects in Experiment 1, with valid cues reducing the right visual field superiority for peripherally located targets, but this interaction was shown to depend on the type of neutral cue. These results provide further support for the role of attentional factors in visual field asymmetries obtained with targets in peripheral vision but not with centrally presented targets.Reading is a complex process that involves extracting visual information from a currently fixated word while simultaneously preparing to extract information from peripherally located words in the text. Therefore, apart from the basic processes involved in extracting information from foveated visual stimuli, reading also involves managing eye movements and attentional resources in order to optimize information extraction across foveal and parafoveal vision. The present study examines the extent to which the appropriate allocation of spatial attention can facilitate word recognition and whether or not the allocation depends on eccentricity. First we review the main findings from past research involving the key manipulations of the present study: the effects of visual field (VF), viewing position (VP), and spatial cuing on visual word recognition.

Effects of prime—target spatial separation and attentional deployment on masked repetition priming

“…Finally, the results of the present study revealed an RVF bias that is consistent with prior research showing visual field asymmetries in visual word recognition (see Ducrot & Grainger, 2007, for a review) and masked repetition priming effects (Marzouki et al, 2007). Attentional asymmetries induced by reading habits provide a unified account of these different visual field effects.…”

Attention and the identification of parafoveal words in school-age children and adults

“…We think that our results better fit with the attentional bias theory. 2 First, we also obtained a larger asymmetric effect of the distractor with the increase in eccentricity from 1.4 to 1.9 (similarly to Ducrot & Grainger, 2007, who compared foveal and parafoveal words), and this is in agreement with the gradient theory of attention developed by Kinsbourne (1993). Second and most importantly, the asymmetric attentional effect was no larger in adults than in children.…”

“…Attentional differences may exist depending on the word's exact location in the visual field (Carrasco, Williams, & Yeshurun, 2002), and parafoveally presented words may require more attention than foveally presented words (Ducrot & Grainger, 2007). When words were displaced from the center of the visual field to a hemifield, Cohen, Dehaene, Vinckier, Jobert, and Montavont (2008) found greater activity in the bilateral posterior intra-parietal cortices and in mesial posterior parietal regions (including precuneus), which have all been involved in visual attention tasks.…”

“…Finally, because the attentional effect may interact with eccentricity (Cohen et al, 2008;Ducrot & Grainger, 2007), we used two different visual angles (1.4 and 1.9 ) between the fixation item and the nearest extremity of the word. We predict larger attentional effects with greater eccentricity.…”

Viewing-position effects in the Stroop task: Initial fixation position modulates Stroop effects in fully colored words

“…A complementary account could be derived from a standard finding in the literature on visual word recognition: Words presented to the right visual field are easier to recognize than words presented to the left visual field (Lindell & Nicholls, 2003). A possible explanation for this asymmetry is that fixations on the left half of the word are less "damaging" than fixations on the right half, because attention can be allocated more rapidly to the right than to the left in people who are trained to read in that direction (see Ducrot & Grainger, 2007). Note that in condition P5 of our experiment, the first fixation was on the last letter of the word, which was thus displayed in the left visual field.…”