Czech adaptation of the Internal Representation Questionnaire and Plymouth Sensory Imagery Questionnaire

Abstract

Objectives. Mental imagery plays a key role in diverse cognitive processes and is typically assessed through self-report instruments. This study presents Czech adaptations of two widely used questionnaires: the Plymouth Sensory Imagery Questionnaire (Psi-Q), which measures the vividness of imagery across seven sensory modalities, and the Internal Representation Questionnaire (IRQ), which captures internal verbalization and visual imagery in non-communicative contexts.
Sample and settings. A large sample of 1,726 Czech-speaking university students completed both instruments in a fully web-based procedure.
Results. Confirmatory factor analyses supported the original seven-factor structure of the Psi-Q and a modified four-factor solution for the IRQ, with improved model fit after the removal of low-loading items. Reliability estimates for both instruments were satisfactory to high. Correlational analyses revealed that the Psi-Q is most strongly related to the Visual Imagery component of the IRQ, while other IRQ components showed only weak associations with sensory imagery. These findings validate the use of the Czech Psi-Q and IRQ and contribute to the cross-linguistic study of individual differences in mental imagery and internal representations.
Limitations. The results support the use of the full seven-factor version of the PsiQ in Czech, particularly when differentiation among sensory imagery dimensions is of interest. In contrast, the single-factor model showed poor fit and is not recommended, reinforcing the interpretation that the PsiQ components represent distinct domains of sensory imagery rather than a unitary construct.