Task-dependent modulation of word processing mechanisms during modified visual search tasks

Abstract

During visual search for words, the impact of the visual and semantic features of words varies as a function of the search task. This event-related potential (ERP) study focused on the way these features of words are used to detect similarities between the distractor words that are glanced at and the target word, as well as to then reject the distractor words. The participants had to search for a target word that was either given literally or defined by a semantic clue among words presented sequentially. The distractor words included words that resembled the target and words that were semantically related to the target. The P2a component was the first component to be modulated by the visual and/or semantic similarity of distractors to the target word, and these modulations varied according to the task. The same held true for the later N300 and N400 components, which confirms that, depending on the task, distinct processing pathways were sensitized through attentional modulation. Hence, the process that matches what is perceived with the target acts during the first 200 ms after word presentation, and both early detection and late rejection processes of words depend on the search task and on the representation of the target stored in memory.

Meaning-based attentional guidance as a function of foveal and task-related cognitive loads

“…target-present displays). As in Dampuré et al (2016), for each search trial, one of the two target words only appeared once and always in the last three-word display. The other target word was repeated at different locations in several threeword displays during a given search trial.…”

“…Accordingly, we expected that, independently of the nature of the search task, the foveal load should be greater when gazing at an infrequent word compared to a frequent word (Henderson & Ferreira, 1990;Schroyens et al, 1999). In addition, previous studies (Dampuré et al, 2014;Dampuré et al, 2016;Léger et al, 2012) have demonstrated that semantic distractors facilitate word processing in the literal task and generate interference in the categorical task. Taken together, we expected more first saccades toward parafoveal semantic distractors (1) in the literal task (low task-related cognitive load) when gazing at a frequent, semantically related word (low foveal load), and (2) in the categorical task (high task-related cognitive load) when gazing at a frequent unrelated distractor (low foveal load), although this latter effect should be weaker due to the higher task-related cognitive load.…”

“…Moores et al, 2003), we expected semantic attentional guidance to be reflected by spontaneous saccades toward parafoveal semantic distractors. We manipulated the task-related cognitive load by varying the nature of the visual search task (Dampuré et al, 2014;Dampuré et al, 2016;Schmidt et al, 2014), which was either a literal (low task-related cognitive load) or a categorical (high task-related cognitive load) search task.…”

Searching for a word in Chinese text: insights from eye movement behaviour

“…Potentials (Dampure, Benraiss, & Vibert, 2016), perhaps with co-registration of eye movements (Dimigen, Sommer, Hohfield, Jacobs, & Kliegl, 2011), may help reveal whether lexical processing does indeed take place during target word search within text.…”

“…It would also be valuable for further research to examine, for both alphabetic and logographic languages, the factors that modulate eye movement behaviour during target word search, for example, the effect of target and distractor word characteristics (Dampure et al, 2016;Léger et al, 2012;Shen & Reingold, 2001;Smith, Lott, & Cronnell, 1969;Spragins et al, 1976). Research with non-linguistic stimuli indicates that eye movement behaviour is affected by the presence of distractors sharing physical characteristics with the target (Findlay, 1997).…”