Offset masking in a divided visual field study

Abstract

A problem in divided visual field studies (especially those using event-related potentials as a dependent measure) is the large number of horizontal eye movements participants make during experimental trials. Past attention research suggests that eye movements to lateralised targets should be significantly reduced using a dynamic, offset mask, causing a reduction in attentional capture. The current study attempted to replicate past divided visual field language studies using offset masking procedures. Using a basic offset procedure, eye movements were not reduced in Experiment 1. However, Experiment 2 did show a significant reduction in eye movements using a new dynamic offset masking procedure. Low accuracy rates were a concern throughout. In conclusion, horizontal eye movements can be reduced with a dynamic offset procedure but the low accuracy rates and the inconsistent behavioural findings throughout the study suggest that further study and refinement of the paradigm is needed.

Keywords:

• DVF
• Eye movements
• Spatial attention
• Laterality

Acknowledgements

We would like to thank Dr Greg Simpson for his input and feedback near the end of this process. We would also like to thank Paul Mattson and Rumpa Yeasin for their part in the data analysis.