Top-Down Prioritization of Salient Items May Produce the So-Called Stimulus-Driven Capture

Area of Science:

• Cognitive Psychology
• Neuroscience
• Visual Perception

Background:

• The phenomenon of stimulus-driven capture suggests that salient visual items automatically attract attention.
• However, the role of top-down attentional control in this process remains debated.

Purpose of the Study:

• To investigate whether top-down attentional prioritization can explain stimulus-driven capture.
• To differentiate between stimulus-driven capture and expectation-based attentional allocation.

Main Methods:

• An expectation-based paradigm using a visual search task was developed.
• Experiments involved presenting task-irrelevant singleton frames at expected and unexpected locations.
• Target identification times were measured under various singleton conditions.

Main Results:

• Participants showed faster target identification in expected singleton locations, even when the singleton was absent (quasi-capture effect).
• Facilitation effects were observed when targets appeared in expected singleton frames, regardless of whether the frame was a singleton or not.
• These findings indicate that attention was top-down allocated to expected locations.

Conclusions:

• Singleton capture can be explained by top-down attentional shifts towards expected salient items.
• Attentional control may exist on a continuous spectrum of top-down influence, encompassing physical salience.
• The study challenges purely stimulus-driven accounts of attentional capture.