Looking at scenes while searching for numbers: dividing attention multiplies space

Area of Science:

• Cognitive Psychology
• Visual Perception
• Memory Research

Background:

• Boundary extension (BE) is a common phenomenon where observers recall a scene as being more expansive than it was.
• The role of visual attention in modulating boundary extension remains an area of active investigation.
• Previous research suggests attentional processes may influence memory distortions in visual perception.

Purpose of the Study:

• To determine if undivided visual attention is a necessary condition for boundary extension (BE).
• To investigate the impact of attentional load on the magnitude of boundary extension.
• To explore the relationship between automatic scene representation and focal attention in memory recall.

Main Methods:

• Three experiments involving 108 observers viewing photographs with superimposed numerals.
• Visual attention was manipulated using a dual-task paradigm: picture rating alone, search task alone, or combined tasks.
• Boundary extension was measured by participants rating test pictures on perceived angle relative to the original image.

Main Results:

• Boundary extension occurred regardless of attentional condition.
• Significantly greater boundary extension was observed when visual attention was divided (dual-task condition).
• Search task accuracy was not affected by the attentional manipulation, indicating task effectiveness.

Conclusions:

• Undivided visual attention is not necessary for boundary extension to occur.
• Divided attention appears to enhance boundary extension, suggesting a role for automatic processes in scene representation.
• Focal attention may act to constrain the extent of boundary errors during scene perception and memory recall.