Grouping and Trajectory Storage in Multiple Object Tracking: Impairments Due to Common Item Motions

Abstract

In our natural viewing, we notice that objects change their locations across space and time. However, there has been relatively little consideration of the role of motion information in the construction and maintenance of object representations. We investigated this question in the context of the multiple object tracking (MOT) paradigm, wherein observers must keep track of target objects as they move randomly amid featurally identical distractors. In three experiments, we observed impairments in tracking ability when the motions of the target and distractor items shared particular properties. Specifically, we observed impairments when the target and distractor items were in a chasing relationship or moved in a uniform direction. Surprisingly, tracking ability was impaired by these manipulations even when observers failed to notice them. Our results suggest that differentiable trajectory information is an important factor in successful performance of MOT tasks. More generally, these results suggest that various types of common motion can serve as cues to form more global object representations even in the absence of other grouping cues.

Neural Measures of Individual Differences in Selecting and Tracking Multiple Moving Objects

“…Consequently, these results suggest that individual differences in tracking performance may be primarily determined by how efficiently the visual system can individuate the targets from one another as well as from the distractors (Sears and Pylyshyn, 2000;Intriligator and Cavanagh, 2001;Ogawa et al, 2002;Vogel et al, 2005;Suganuma and Yokosawa, 2006).…”

Speed has an effect on multiple-object tracking independently of the number of close encounters between targets and distractors

“…Thus, we believe it unlikely that the lack of an interaction was due to the range of speeds or distances used. In this experiment, tracking might have been affected not only by spatial proximity, but also by temporal proximity (Verstraten et al, 2000) and similarity of motion (Suganuma & Yokosawa, 2006) of the targets and distractors, which may have been increased in the near distance condition. Previous studies have shown that MOT performance declines as the number of distractors increases (Bettencourt & Somers, 2009;Feria, 2012;Sears & Pylyshyn, 2000;Tombu & Seiffert, 2011).…”

Do objects in working memory compete with objects in perception?

“…Object files may store various visual and spatial features of objects, such as colour, orientation, and location (Treisman, 2006). In contrast, indices only select and refer to individual objects (Pylyshyn, 2007)*although some writers have proposed that in some cases there may be a compulsory encoding of location in the associated object files (Fencsik, Klieger, & Horowitz, 2007;Keane & Pylyshyn, 2006;Suganuma & Yokosawa, 2006). But perceptual information does not appear to be routinely encoded.…”