Advance information modulates the global effect even without instruction on where to look

Area of Science:

• Cognitive Neuroscience
• Ophthalmology
• Visual Perception

Background:

• The global effect describes eye movements landing between a target and distractor.
• Previously considered mandatory, explicit instructions can now override this effect.

Purpose of the Study:

• To investigate if top-down influences affect eye movements during implicit tasks.
• To determine if advance information guides gaze without explicit eye movement instructions.

Main Methods:

• Participants identified target letters in arrays of colored discs.
• Eye movement landing sites were analyzed during a secondary task.
• Fixation durations were manipulated to assess timing of influences.

Main Results:

• Observers used advance information about target color to guide eye movements implicitly.
• Implicit top-down influences operated on a similar timescale as explicit instructions.

Conclusions:

• Top-down influences are not limited to explicit eye movement tasks.
• Implicit guidance of eye movements is a significant factor in visual search.