Testing a postselectional account of across-dimension switch costs

Area of Science:

• Cognitive Psychology
• Visual Perception
• Human Information Processing

Background:

• Across-dimension switch costs in visual search are well-documented.
• The precise cognitive stage responsible for these costs remains debated, with theories positing effects on attention guidance versus response selection.

Purpose of the Study:

• To investigate whether across-dimension switch costs in visual search affect early attentional guidance or later response selection processes.
• To test predictions derived from a response-selection account of these switch costs.

Main Methods:

• Participants performed a visual search task involving pop-out targets.
• The study manipulated the repetition or change of the target dimension across trials.
• Eye movements and response times were recorded to differentiate between attention guidance and response selection.

Main Results:

• Switch costs were observed even when visual attention was guided by a distinct feature, supporting the response-selection account.
• Changes in the target dimension significantly impacted response speed but did not affect the speed of eye movements toward the target.
• These results indicate that attentional guidance processes were not hindered by dimension changes.

Conclusions:

• Across-dimension switch costs in visual search do not influence early processes of attention guidance.
• These costs arise from later cognitive stages, specifically target identification or response selection, occurring after attentional selection.
• The findings refine our understanding of the temporal dynamics of visual search and cognitive control.