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.