Global interference and field independence in hierarchical visual processing

Abstract

Complex hierarchical visual stimuli are composed of a large structure (global level) that is made up of small details (local level). Global and local information of an object are initially processed independently, and global information can be processed more readily than local information. When people are required to focus on the local level, they are easily distracted by information from the global level, while they are less distracted by the local level when processing the global level. This is referred to as global interference. A related concept, field independence, describes people’s ability to differentiate local target shapes from the shapes’ surroundings. Despite the conceptual similarity between global interference and field independence, it is unknown to what extent they rely on similar processes. Furthermore, the role of meaning in processing local and global features may influence the processes that are similar across global interference and field independence. We investigated the correlation between global interference and field independence and manipulated the meaningfulness of visual stimuli. We measured global interference with a Navon task, and measured field independence with an Embedded Figures Test. The Navon stimuli were either letter, object, or non-object (abstract/non-meaningful) compound stimuli. In the Embedded Figures Test, we utilized both object and non-object global figures where the local shapes (i.e., squares, triangles, etc.) were embedded. Global interference and field independence were only correlated when the stimuli in the Navon task were meaningful objects. In addition, global interference was stronger for letter stimuli in the Navon task, whereas field independence was weaker for the meaningful stimuli in the EFT, suggesting that meaningfulness plays a critical role in both global interference and field independence and when they rely on similar processing.