Visual attention in a multiple-choice task: Influences of image characteristics with and without presentation of a verbal stimulus
Posted by Callier Library on April 3, 2008
from Aphasiology
Background: Use of multiple-choice items is common in the assessment of language comprehension. Stimulus-driven aspects of multiple-choice images may interfere with valid assessment. Understanding the influences of stimulus-driven factors is crucial because individuals with neurological disorders have increased susceptibility to them.
Aims: The first goal of this study was to explore the influence of objectively measurable image characteristics in multiple-choice image sets that are otherwise well controlled in terms of physical stimulus features on individuals’ visual attention. The second goal was to explore viewers’ visual attention under the influence of a verbal stimulus.
Methods & Procedures: The effects of controlled manipulation of physical image characteristics on visual attention in 40 healthy adults were assessed. Eye movements were recorded while participants viewed 40 image sets with and without a verbal stimulus. Within each set, two images shared the same image characteristics (colour, orientation, size, and luminance) and one image differed in terms of one of those characteristics.
Outcomes & Results: All characteristics had a significant influence on visual attention in verbal and nonverbal conditions. The influence of verbal stimuli on visual attention did not override the tendency for physical stimulus characteristics to distract attention from target images.
Conclusions: Research and clinical relevance is highlighted in terms of the potential for assessment confounds to be greater in individuals with neurological impairments.
This study was supported in part by a grant (# DC 0015301 A1) from the National Institute on Deafness and other Communication Disorders of the National Institutes of Health, an Ohio University Graduate Student Senate Original Work grant, and an Ohio University Graduate Fellowship Award. The authors thank Dr Hans Kruse for stimulus presentation and analysis software design, Dr Helmut Zwahlen for technical assistance in physical stimulus control, and Anshula Odekar, Maria Ivanova, and Tae Asahina for assistance with data collection.
