Effects of visual time constraint on verbal fluency task performance

Effects Of Visual Time Constraint On Verbal Fluency Task Performance

Introduction

Language input enters the human parsing system in an incremental fashion regardless of modality. During reading, words reach our eyes moment by moment as we make successive fixations across text on a page. Similarly, during listening, words make contact with our ears as speakers' utterances unfold word by word. An important consequence of incremental production and comprehension is that readers and listeners are frequently faced with temporary ambiguities about how best to structure the input in real- time. Consider, for example, the following illustration of this:

The visual referent world that accompanied each particular target sentence either supported the Goal analysis or supported the Modifier analysis. The Goal analysis was supported by having just one apple present sitting on a towel, and a 'luring' Incorrect Goal (an empty towel). The Modifier analysis was supported by having two apples in the scene, one of which was on a towel, plus the luring Incorrect Goal. Within 1-Apple Scenes, eye fixation patterns showed that listeners rapidly committed to the Goal interpretation of on the towel and were 'surprised' by the presence of a second Goal phrase such as into the box. This was illustrated by a high proportion of early looks to the Incorrect Goal in the scene, the empty towel, at the onset of hearing towel. Upon encountering into the box, listeners then redirected their eyes and engaged in a process of finding a new analysis of on the towel that permitted into the box to be the Goal. Crucially, however, when aspects of the contextual scene supported the Modifier interpretation, Tanenhaus and colleagues found that listeners were unsurprised by into the box, and that lexical biases associated with put were completely overridden in light of a 2-Apple Scene that supported a Modifier interpretation (Tanenhaus et al., 1995). Virtually no early looks to an Incorrect Goal were observed, and eye movement patterns were essentially identical to those that arose in response to syntactically unambiguous control sentences (for similar studies and replications of these results, see also Spivey et al., 2002 and Trueswell et al., 1999). In addition, Chambers, Tanenhaus, and Magnuson (2004) found that pragmatic factors also influence ambiguity resolution for sentences of this type. When hearing Pour the egg in the bowl onto the flour, the affordances of task-relevant objects modulated looks to an Incorrect Goal. In particular, the presence of two liquid eggs generated eye movement patterns similar to the 2-Referent Scenes described above (i.e., no increased looks to the Incorrect Goal relative to unambiguous controls). However, changing one of the liquid eggs to a hard-boiled egg generated eye movements similar to 1-Referent Scenes (i.e., increased Incorrect Goal looks).

These results have been widely regarded as a compelling demonstration of how multiple sources of evidence from both the linguistic input and the non-linguistic visual context can rapidly conspire to guide listeners toward the correct analysis of the sentence, thus supporting constraint -based interactive perspectives ([Spivey ...