Are onscreen cursor movements influenced by the Ebbinghaus illusion? Exploring perception-action interaction in a...

Area of Science:

• Cognitive Psychology
• Neuroscience
• Human-Computer Interaction

Background:

• The Two-Visual-Streams Hypothesis (TVSH) posits distinct neural pathways for visual perception and action control.
• Previous research supports this separation, but its application to onscreen environments requires further investigation.

Purpose of the Study:

• To investigate if the TVSH's proposed separation of perception and action applies to visually guided cursor movements on a computer screen.
• To determine if perceptual distortions of target size influence action execution in a digital interface.

Main Methods:

• Participants performed trackpad-based cursor movements to click onscreen targets.
• The Ebbinghaus illusion was used to manipulate the perceived size of targets.
• Visual feedback conditions were varied, including continuous feedback, immediate removal, and delayed removal.

Main Results:

• Accuracy in clicking targets was influenced by their perceived size, supporting the role of perception in guiding action.
• The illusion's effect on accuracy disappeared when visual feedback was removed, even after a brief viewing period.

Conclusions:

• Perceptual characteristics of onscreen stimuli directly influence the guidance of actions toward visible targets.
• The TVSH's principles are supported in digital environments, but only when visual feedback is present.
• Action guidance relies on real-time perceptual information, not on stored or illusory size perceptions when targets disappear.