Development of multiple object tracking via multifocal attention

"Catastrophic" set size limits on infants' capacity to represent objects: A systematic review and Bayesian meta-analysis

Decades of research has revealed that humans can concurrently represent small quantities of three-dimensional objects as those objects move through space or into occlusion. For infants (but not older children or adults), this ability apparently comes with a significant limitation: when the number of occluded objects exceeds three, infants experience what has been characterized as a "catastrophic" set size limit, failing to represent even the approximate quantity of the hidden array. Infants' apparent catastrophic representational failures suggest a significant information processing limitation in the first years of life, and the evidence has been used as support for prominent theories of the development of object and numerical cognition. However, the evidence for catastrophic failure consists of individual small-n experiments that use null hypothesis significance testing to obtain null results (i.e., p > 0.05). Whether catastrophic representational failures are robust or reliable across studies, methods, and labs is not known. Here we report a systematic review and Bayesian meta-analysis to examine the strength of the evidence in favor of catastrophic representational failures in infancy. Our analysis of 22 experiments across 12 reports, with a combined total of n = 367 infants aged 10-20 months, revealed strong support for the evidence for catastrophic set size limits. A complementary analysis found moderate support for infants' success when representing fewer than four objects. We discuss the implications of our findings for theories of object and numerical cognitive development. RESEARCH HIGHLIGHTS: Previous work has suggested that infants are unable to concurrently represent four or more objects-a "catastrophic" set size limit. We reviewed this work and conducted a Bayesian meta-analysis to examine the robustness of this limit across individual small-n experiments. We found strong support for the evidence for catastrophic set size limits, and moderate support for infants' success when representing fewer than four objects.

Deficits in multiple object-tracking and visual attention following mild traumatic brain injury

Difficulty in the ability to allocate and maintain visual attention is frequently reported by patients with traumatic brain injury (TBI). In the present study, we used a multiple object tracking (MOT) task to investigate the degree to which TBI affects the allocation and maintenance of visual attention to multiple moving targets. Fifteen adults with mild TBI and 20 control participants took part in this study. All participants were matched for age, gender, and IQ. The sensitivity and time taken to perform the MOT task were measured for different conditions in which the duration of the tracking, number of target, and distractor dots were systematically varied. When the number of target dots required to be tracked increased, sensitivity in correctly detecting them decreased for both groups but was significantly greater for patients with mild TBI. Similarly, increasing the number of distractor dots had a greater effect on reducing task sensitivity for patients with mild TBI than control participants. Finally, across all conditions, poorer detection performance was observed for patients with mild TBI when the tracking duration was longer compared to control participants. The present study showed that patients with mild TBI have greater deficits (compared to control participants) in their ability to maintain visual attention on tracking multiple moving objects, which was particularly hindered by increased tracking load and distraction.

Effects of Physical Exercise and Virtual Training on Visual Attention Levels in Children with Autism Spectrum Disorders

This study compared the effects of physical exercise (PE) and virtual training (VT) on the improvement of the visual attention mechanism in children with autism spectrum disorders (ASD). One hundred eighty-nine children with ASD were recruited from Orphan School in Liaoning Province, China. After screening, 100 children ultimately participated in the experiment. Children with ASD were randomly assigned to VT (VT, n = 34), PE (PE, n = 33) and control group (CG, n = 33). The VT group experiment was performed in a virtual environment through the game FIFA21 three times per week for 6 weeks. The PE group played physical football matches three times per week for 6 weeks. Children with ASD in the CG group did not receive VT or PE but only received psychological counseling. Visual attention of children with ASD is evaluated by using the multiple object tracking paradigm (MOT). After 6 weeks of observation, although none of the three groups saw improvements in the correct rate of ring tracking, the observations of the VT and PE groups were significant (p < 0.05) compared to the CG group in finding detection rate of probe stimulus. Through MOT tests, VT and PE improved the detection rate of probe stimulus in children with ASD. Therefore, this paper indicates that VT and PE can improve the visual attention ability of children with ASD.

Hemifield-specific control of spatial attention and working memory: Evidence from hemifield crossover costs

Attentional tracking and working memory tasks are often performed better when targets are divided evenly between the left and right visual hemifields, rather than contained within a single hemifield (Alvarez & Cavanagh, 2005; Delvenne, 2005). However, this bilateral field advantage does not provide conclusive evidence of hemifield-specific control of attention and working memory, because it can be explained solely from hemifield-limited spatial interference at early stages of visual processing. If control of attention and working memory is specific to each hemifield, maintaining target information should become more difficult as targets move between the two hemifields. Observers in the present study maintained targets that moved either within or between the left and right hemifields, using either attention (Experiment 1) or working memory (Experiment 2). Maintaining spatial information was more difficult when target items moved between the hemifields compared with when target items moved within their original hemifields, consistent with hemifield-specific control of spatial attention and working memory. However, this pattern was not found for maintaining identity information (e.g., color) in working memory (Experiment 3). Together, these results provide evidence that control of spatial attention and working memory is specific to each hemifield, and that hemifield-specific control is a unique signature of spatial processing.