Reliability of non-verbal laterality effects in the visual modality

Area of Science:

• Cognitive Neuroscience
• Visual Perception
• Human Psychology

Background:

• Laterality effects, or brain hemisphere dominance, are well-documented in various cognitive tasks.
• Non-verbal tasks in the visual modality are often used to study these effects.
• Controlling attention is crucial for reliably measuring laterality effects.

Purpose of the Study:

• To investigate the reliability and magnitude of laterality effects in a non-verbal visual task.
• To determine if a bilateral discrimination task controls attention deployment effectively.
• To examine the influence of practice on visual laterality effects.

Main Methods:

• Utilized a bilateral discrimination task with centrally presented probes and bilateral targets.
• Employed a test-retest design with 40 right-handed undergraduate students.
• Measured laterality effects in two separate testing sessions.

Main Results:

• High test-retest correlations indicated reliable laterality effects.
• A significant left visual field advantage (LVFA) was found in the first session.
• A right visual field advantage emerged in the second session, suggesting a practice effect.

Conclusions:

• Visual laterality effects demonstrate high reliability but can be influenced by practice.
• Practice appears to alter the direction of laterality effects in non-verbal visual tasks.
• Attentional factors and shifts in score distributions may explain the observed changes with practice.