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Measuring Attention and Visual Processing Speed by Model-based Analysis of Temporal-order Judgments
Published on: January 23, 2017
Context effects in pseudo-neglect measured with a free vision Landmark task
Linda Rueckert1, Harvey Gene McFadden
1Department of Psychology, Northeastern Illinois University, Chicago, IL 60625, USA. L-Rueckert.@neiu.edu
Laterality
|October 30, 2004
Summary
In normal individuals, line bisection perception depends on actual line length, not relative length. Wider backgrounds unexpectedly eliminated the crossover effect, suggesting context influences perception.
Area of Science:
- Cognitive Psychology
- Neuroscience
- Visual Perception
Background:
- Neglect patients show a line bisection crossover effect, influenced by relative line length.
- This study investigates if context influences this effect in normal participants.
Purpose of the Study:
- To determine if the line bisection crossover effect in normal participants is context-dependent.
- To explore the influence of relative line length versus absolute line length on perception.
- To examine the impact of background width on line bisection judgments.
Main Methods:
- Participants performed a free vision Landmark task, judging bisection accuracy.
- Study 1: Lines presented in blocks of either short (1-8 cm) or long (8-28 cm) durations.
- Study 2: Line background width was manipulated (standard vs. doubled).
Main Results:
- Study 1: Perception was influenced by absolute line length, not relative length, differing from neglect patients.
- Study 2: The crossover effect disappeared in a wide field width condition.
- Unexpectedly, wider backgrounds eliminated the crossover effect.
Conclusions:
- Normal participants' line bisection perception is less context-dependent than neglect patients' based on relative length.
- The crossover effect may arise from an interaction between the line and its background.
- Visual context, specifically background width, significantly impacts line bisection judgments.
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