Mental arithmetic and non-speech office noise: an exploration of interference-by-content.

An interference-by-content account of auditory distraction - in which the impairment to task performance derives from the similarity of what is being recalled and what is being ignored - was explored concerning mental arithmetic performance. Participants completed both a serial recall and a mental arithmetic task in the presence of quiet, office noise with speech (OS) and office noise without speech (ONS). Both tasks revealed that the two office noise condition's significantly impaired performance. That the ONS produced this deficit suggests that an interference-by-content account cannot explain impairment to mental arithmetic performance by background sound.

The role of rehearsal in a novel call center-type task.

Laboratory research has long demonstrated the disruptive effects of background sound to task performance yet the real-world implications of such effects are less well known. We report two experiments that demonstrate the importance of the role of rehearsal to a novel call center-type task. In Experiment 1, performance of a novel train timetable task-in which participants identified four train journeys following presentation of train journey information-was disrupted by realistic office noise. However, in Experiment 2, when the need for rehearsal was reduced by presenting the information and the timetable at the same time, no disruption occurred . Results are discussed in terms of interference-by-process and interference-by-content approaches to short-term memory.

Using auditory streaming to reduce disruption to serial memory by extraneous auditory warnings.

Three experiments were conducted to examine the effects of extraneous speech warnings (i.e., low-priority warnings initiated during high-priority tasks) on cognitive performance and whether organizing the auditory warnings into streams can attenuate any disruption. Experiment 1 demonstrated that a variety of speech warnings can be separated into perceptually distinct streams by allocating them to discrete spatial locations. Experiment 2 showed that increasing the rate of presentation of the warnings to promote streaming decreased clarity ratings but increased perceived urgency ratings. Experiment 3 demonstrated that the disruption to serial memory for navigational information by extraneous speech warnings could be attenuated by streaming. Results are interpreted in light of previous research, and practical implications for auditory warning design are discussed.

Designing information fusion for the encoding of visual-spatial information.

In a simulated aircraft navigation task, a fusion technique known as triangulation was used to improve the accuracy and onscreen availability of location information from two separate radars. Three experiments investigated whether the reduced cognitive processing required to extract information from the fused environment led to impoverished retention of visual-spatial information. Experienced pilots and students completed various simulated flight missions and were required to make a number of location estimates. Following a retention interval, memory for locations was assessed. Experiment 1 demonstrated, in an applied setting, that the retention of fused information was problematic and Experiment 2 replicated this finding under laboratory conditions. Experiment 3 successfully improved the retention of fused information by limiting its availability within the interface, which it is argued, shifted participants' strategies from over-reliance on the display as an external memory source to more memory-dependent interaction. These results are discussed within the context of intelligent interface design and effective human-machine interaction.

Reduction in auditory distraction by retrieval strategy.

Most research on auditory distraction on task performance focuses on those features of the sound that determine a drop in efficiency, with scant regard for examining the processing properties inherent in the focal task. We report how one such property, retrieval strategy, can also influence the degree of disruption by background sound. Using a task that called for the retrieval of realistic train journey information, we showed that retrieval by categories of verbal sequences was not susceptible to disruption by office sound - 65-75 dB(A). However, versions of the task requiring either free or serial recall showed evidence of disruption, a pattern of results consistent with the changing-state account of the irrelevant sound effect, which highlights the key role of serial rehearsal in determining disruption.