Disposition towards hallucination and subjectiveversus objective vividness of imagery in normal subjects

In the present study we investigated the relation between subjective and objectiveindices of vividness of imagery and disposition towards hallucination in 74 college students.Self-reported imagery vividness was measured with the visual and auditory subscales of the BettsQMI Vividness of Imagery Scale. The objective task concerned the difference between aperceptual and an imagery condition of judgment of visual similarity of named objects. Inaddition, subjects completed a hallucination questionnaire (the Launay-Slade HallucinationScale). After assigning subjects to a high and a low scoring group on the basis of scores on thehallucination scale, analysis of variance revealed a significant interaction between group and thetwo vividness of imagery measures. Subjects reporting hallucinatory experiences tended to showhigher imagery vividness ratings on the Betts Scale than nonhallucinating subjects. In contrast,the reverse relation was found on the experimental imagery task. Implications of these findingsfor the validity of self-report imagery vividness measures are discussed. Directions for futureresearch are outlined.