ABSTRACT
This chapter shows that the task of defining and measuring the different characteristics of mental imagery needs more careful thought and research attention than has often been given to it. Relatively stable individual differences have been found for three conceptually and methodologically distinct qualities of thought imagery. These are the primary qualities to be discussed, and refer to: the typical average level of vividness achievable, the typical average degree of control that can be exercised, and the typical, habitual, or preferred mode for the spontaneous conscious representation of thought content. The chapter considers these qualities in more detail and provides information two others that should be mentioned because they have aroused sufficient interest to produce provisional methods for their assessment. These refer to the apparent position of the imager when imaging (orientation), and to the apparent location of the image (localization).
