Relationship between Selective Attention and Ensemble Perception
Visual Attention Lab, Harvard University2020
- Background: Our visual system copes with limited capacity using two different modes of attention, a distributed attention mode extracting the gist of a scene (i.e., ensemble perception) and a focused attention mode selecting only relevant information (i.e., selective attention). These two modes of processing serve different purposes. Still, it is unclear how they work together, whether they conflict with each other, and how cognitive control might play a role in conciliating their different processing demands.
- Designed and programmed experiments, collected data and conducted analyses with MATLAB.
- Developed a novel paradigm incorporating the mean orientation discrimination task and target orientation detection task. Introduced a single-task condition (requiring only one mode of processing), a dual-task condition (requiring both modes of processing), and a mixed-task condition (requiring either one or two modes of processing across trials).
- Discovered that people’s performance in target selection and ensemble discrimination tasks positively correlated in both single-task and dual-task conditions, indicating some shared neural mechanisms underlying selective attention and ensemble perception. The mixed-task condition significantly impaired ensemble discrimination performance rather than target selection performance, suggesting a cognitive control strategy favoring selective attention when faced with conflicts in processing demands.