Object tracking: absence of long-range spatial interference supports resource theories

Area of Science:

• Cognitive psychology
• Neuroscience
• Psychophysics

Background:

• Attentional tracking of moving targets can be hindered by additional objects.
• This impairment may stem from spatial interference or the division of limited attentional resources.

Purpose of the Study:

• To investigate the impact of target separation on attentional tracking performance.
• To differentiate between spatial interference and resource division as explanations for dual-target tracking costs.

Main Methods:

• Six experiments were conducted to assess the effect of separation between two targets on tracking performance.
• Performance was measured in both one-target and two-target conditions under varying target separations.

Main Results:

• Tracking performance improved with separation within the crowding zone but not beyond it.
• No long-range spatial interference was observed; dual-target tracking remained significantly poorer than single-target tracking at large separations.
• In the one-target condition, increased separation from distractors unexpectedly reduced performance, possibly indicating a configural tracking process.

Conclusions:

• The cost of tracking multiple targets is better explained by hemisphere-specific attentional resource theories than by spatial interference.
• Spatial proximity is not the primary factor limiting dual-target attentional tracking beyond the crowding zone.