A Psychometric Analysis of the VVIQ

In a moment, close your eyes and try to picture an apple. When you do, pay attention to what you can visualize: Can you picture its color and size? Can you rotate it Can you picture it in a natural environment? Can you see it at all? Alright—go ahead and try.

For most of us, this task is trivial. However, around 2% (Faw, 2009; Watkins, 2019; Zeman, 2024) of the population is unable to visualize anything at all. This condition, known as aphantasia, is defined as the inability to conjure mental images, i.e., the lack of a “mind’s eye.”

Measuring acuity of mental visualization is difficult for a variety of reasons. One of the most prominent is that visualization is inherently a private process—and the terms that are used in colloquial language (such as “imagine” or “picture”) may be misunderstood or misconceptualized by individuals when they are asked to conjure a mental image. One of the most common scales used to assess this construct is the VVIQ—the Vividness of Visual Imagery Questionnaire. This scale contains items that ask participants to try and visualize with their eyes closed and with their eyes opened.

Little work has assess the psychometric properties of this scale. Due to the messy nature of the items (item are asked twice under differing conditions), Exploratory Factor Analysis fails to capture the underlying factor structure. I utilized more complex models and an Item Response Theory framework to assess dimensionality and item parameters. Overall, I found that yes! Visualization as a latent construct does seem like it differs for individuals between the eyes-opened and eyes-closed conditions.