Shared processing in multiple object tracking and visual working memory in the absence of response order and task order confounds.

Mark D Lapierre,Piers D L Howe,Simon J Cropper,Nicholas Seow Chiang Price

doi:10.1371/journal.pone.0175736

Abstract

To understand how the visual system represents multiple moving objects and how those representations contribute to tracking, it is essential that we understand how the processes of attention and working memory interact. In the work described here we present an investigation of that interaction via a series of tracking and working memory dual-task experiments. Previously, it has been argued that tracking is resistant to disruption by a concurrent working memory task and that any apparent disruption is in fact due to observers making a response to the working memory task, rather than due to competition for shared resources. Contrary to this, in our experiments we find that when task order and response order confounds are avoided, all participants show a similar decrease in both tracking and working memory performance. However, if task and response order confounds are not adequately controlled for we find substantial individual differences, which could explain the previous conflicting reports on this topic. Our results provide clear evidence that tracking and working memory tasks share processing resources.

Highlights

Despite living in a dynamic environment, with retinal images that are continuously changing, observers can create and maintain a coherent perceptual representation of their external environment
Tracking was better in the single-task condition than in the Visual Working Memory (VWM)-response first condition, but not the Multiple-Object Tracking (MOT)-response first condition
Accuracy was greater under single-task conditions compared to dual-task conditions for MOT performance and VWM performance

Summary

Introduction

Despite living in a dynamic environment, with retinal images that are continuously changing, observers can create and maintain a coherent perceptual representation of their external environment. To create this representation, observers need to identify and label individual objects and to keep track of their whereabouts. For observers to know which objects are located where in the visual environment, these two processes must interact coherently and effectively. How this happens remains a contentious issue. We review several recent studies and present our own to show how their seemingly disparate conclusions can be brought together to form a more cogent view of the shared processing in tracking and working memory

Objectives

Results

Conclusion