When people search a display for a target defined by a unique feature, fast saccades are predominantly stimulus-driven whereas slower saccades are primarily goal-driven. Here we use this dissociative pattern to assess whether feature-based selection in patients with lateralized spatial attention deficits is impaired in stimulus-driven processing, goal-driven processing, or both. A group of patients suffering from extinction or neglect after parietal damage, and a group of healthy, age-matched controls, were instructed to make a saccade to a uniquely oriented target line which was presented simultaneously with a differently oriented distractor line. We systematically varied the salience of the target and distractor by changing the orientation of background elements, and used a time-based model to extract stimulus-driven (salience) and goal-driven (target set) components of selection. The results show that the patients exhibited reduced stimulus-driven processing only in the contralesional hemifield, while goal-driven processing was reduced across both hemifields.
- Stimulus-driven selection
- Goal-driven selection
- Eye movements
Dombrowe, I., Donk, M., Wright, H., Olivers, C. N., & Humphreys, G. W. (2012). The contribution of stimulus-driven and goal-driven mechanisms to feature-based selection in patients with spatial attention deficits. Cognitive Neuropsychology, 29(3), 249-274. https://doi.org/10.1080/02643294.2012.712509