The characterization of attention resource capacity and its relationship with fluid reasoning intelligence: A multiple object tracking study

Multiple object-tracking (MOT) paradigms have the potential to highlight attention resource capacities. However, there is a dearth in research exploring the relationship between individual differences in MOT capability and higher-level cognition, such as intelligence. Previous research has demonstrated that manipulating task demands, or the task's cognitive load, can help describe this relationship. Therefore, we assessed the relationship between performance on a 3D-MOT task at different levels of cognitive load (average speed for tracking 1, 2, 3 and 4 target objects out of 8 total objects), and fluid reasoning intelligence measured by the Wechsler Abbreviated Scale of Intelligence-2nd edition (WASI-II). Also, we compared MOT performance between intellectual styles classified as: (i) low, medium or high fluid reasoning IQ, and (ii) fluid reasoning or verbal styles. As expected, speed scores decreased as target objects increased. This trend represents a proxy for attentional resource capacity as manipulations to both speed and target objects are able to highlight individual differences in available attentional resources. Furthermore, MOT capability at high load (4-targets) was the best predictor of fluid reasoning intelligence compared to lower loads (1-3 targets), and individuals with a fluid reasoning style and/or medium-high fluid reasoning intelligence outperformed individuals with a verbal style and low fluid reasoning IQ, respectively. These results describe the underlying commonalities between fluid reasoning intelligence and attention resource capacity, extending previous findings with working memory capacity. This study demonstrates that examining MOT as a measure of attention, rather than a phenomenon, can illustrate the potential to repurpose the use of this task to characterize attentional resource capacity.