Alison Sanford

Shallow Processing and Attention Capture in Written and Spoken Discourse

Processing of discourse seems to be far from uniform with much evidence indicating that it can be quite shallow. The question is then what modulates depth of processing? A range of discourse devices exist that we believe may lead to more detailed processing of language input (Attention Capturers), thus serving as modulators of processing enabling some parts of discourse to be processed more than others. We list some of these and describe two in detail. We introduce the text-change procedure in which texts are presented twice in succession with a possible change to a word on the second presentation. By analogy with visual change-blindness, text change provides a method of tracking attention capture and depth of processing in text. In Experiment 1, the effect of italicization in writing was investigated. Italicization led to an increase in change detection. In Experiment 2, we investigated focus-driven word stress in speaking. Once again, focus-driven stress led to increases in change detection. These examples show how word stress increases depth of processing. We discuss the findings in terms of the Granularity account of focus, in which deeper processing is characterized as a more detailed semantic specification.

Anomalies at the borderline of awareness: An erp study

Behaviorally, some semantic anomalies, such as those used to demonstrate N400 effects in ERPs, are easy to detect. However, some, such as “after an air crash, where should the survivors be buried?” are difficult. The difference has to do with the extent to which the anomalous word fits the general context. We asked whether anomalies that are missed elicit an ERP that could be taken as indicating unconscious recognition, and whether both types elicit an N400 effect when they are detected. We found that difficult anomalies having a good fit to general context did not produce an N400 effect, whereas control “easy-to-detect” anomalies did. For difficult anomalies, there was no evidence for unconscious detection occurring. The results support a qualitative distinction in the way the two types of anomalies are processed, and the idea that semantic information is simply not utilized (shallow processing) when difficult anomalies are missed.

Enhancement and suppression effects resulting from information structuring in sentences

Information structuring through the use of cleft sentences increases the processing efficiency of references to elements within the scope of focus. Furthermore, there is evidence that putting certain types of emphasis on individual words not only enhances their subsequent processing, but also protects these words from becoming suppressed in the wake of subsequent information, suggesting mechanisms of enhancement and suppression. In Experiment 1, we showed that clefted constructions facilitate the integration of subsequent sentences that make reference to elements within the scope of focus, and that they decrease the efficiency with reference to elements outside of the scope of focus. In Experiment 2, using an auditory text-change-detection paradigm, we showed that focus has similar effects on the strength of memory representations. These results add to the evidence for enhancement and suppression as mechanisms of sentence processing and clarify that the effects occur within sentences having a marked focus structure.

Audio channel constraints in video-mediated communication

This study investigated the effects of two types of audio channels upon the effectiveness of task-based interactions in a video-mediated context (VMC). Forty undergraduates completed a collaborative task (The Map Task) using either a full or half-duplex audio channel. Their performance was compared to face-to-face interactions, taken from the Human Communication Research Centre corpus of Map Task Dialogues. Effects of varying the audio channel were explored by comparing task performance, patterns of speech, and establishment of mutual understanding. Users of the full-duplex VMC made insufficient allowance for the VMC context; they completed the task less accurately than face-to-face participants, and interrupted each other more frequently than other participants. Participants in the half-duplex VMC however performed as well as face-to-face participants. They made sensible adaptations to the constraints imposed by the half-duplex VMC context, producing longer dialogues, with more explicit turn-taking management, and taking greater care in establishing mutual knowledge.