1991/01/01 by Asher Cohen, Richard B. Ivry · 1 citation
Neuroscience · #Visual perception and processing mechanisms #Neural and Behavioral Psychology Studies #Spatial Neglect and Hemispheric Dysfunction
paper · doi:10.1037/0096-1523.17.4.891
openalex publication_date 1991/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/11
Four experiments used the visual search paradigm to examine feature integration mechanisms. Reaction time to determine the presence or absence of a conjunctive target is relatively fast and exhaustive for low-density displays. Search rate is slow and self-terminating for high-density displays. Density effects do not arise when the target is defined by a unique feature. Two mechanisms are proposed for feature integration. A fast mechanism integrates features on the basis of coarse location information coded with the initial registration of the features. This coarse location mechanism requires that display items be spaced apart. A second, slower mechanism is used when objects are clumped together. The 2-mechanism hypothesis provides a resolution to conflicting findings in the visual search and illusory-conjunction literature. A possible interpretation of the findings with a single guided search mechanism for feature integration is also discussed.