Imagery is used in intellectual disability education; however, previous findings on imagery abilities in intellectual disabilities are inconsistent. This study examined the visual and multisensory imagery abilities of individuals with intellectual disabilities and assessed their response reliability. Twenty-six individuals with mild intellectual disabilities (ID) and 34 with typical development (TD) completed the questionnaire on vividness of visual imagery (VVIQ) and multisensory imagery (QMI) twice (first and second sessions). The results showed significant group differences in the VVIQ total score and some VVIQ subfactors only in the first session, but not in the QMI. These VVIQ subfactors showed poor or borderline moderate reliability in ID; however, other VVIQ subfactors and the QMI showed moderate or good reliability. The poor or borderline moderate reliability of the VVIQ may result from language expression/comprehension issues. This study suggests that caution is needed when interpreting the response reliability of some VVIQ subfactors in ID.
Junichi Takahashi (Mon,) studied this question.