2020 Volume 17 Issue 1 Pages 13-36
This paper points out that there have been many studies using subjective imagery tests and many findings concerning imagery tests, but there have only been a few inquiries into the mechanisms of imagery ability among imagery researchers, and attempts, on the basis of Hatakeyama’s（2018b） review article, which surveyed predictive effects of imagery tests in cognitive tasks or events, to identify the mechanisms of each dimension of imagery ability, that is, vividness, controllability, preference（imagery type）, and absorption, and to present core characteristics of those dimensions. The identified mechanisms are as follows（asterisk means the mechanism on which the dimension is thought to be based and no mark means the mechanism that is brought as an effect by the dimension）. Vividness: neuropsychological bases*, rich perceptual input*, rich perceptual information of long term memory*, large capacity of visual working memory*, attention to the details of a stimulus*, rich information within the image*, rapid image generation*, functional equivalence to perception, spontaneous use of imagery strategy, memorization using imagery encoding, and control of physiological response. Controllability: cognitive/adaptive flexibility*, flexible image generation*, efficient allocation and change of attention*, wide-ranging use of perceptual information within long-term memory*, rich information within the image, spontaneous use of imagery strategy, faithful execution of imagery instruction, encoding of scene/story development, and memorization using imagery encoding. Preference: neuropsychological bases*, encoding that corresponds to imagery type*, rich perceptual input*, rich perceptual information of long-term memory*, wide-ranging use of perceptual information within long-term memory*, large capacity of visual working memory*, functional equivalence to perception, spontaneous use of imagery strategy, memorization using imagery encoding, and control of physiological response. Absorption: strong imaginative involvement*, induction of relaxation*, and control of physiological response. The core characteristics of each dimension are as follows. Vividness: rich information within the image and easy maintenance and robustness of the image; controllability: cognitive/adaptive flexibility; preference: characteristic that directs encoding at the time of stimulus input and subsequent processing; absorption: strong imaginative involvement and easy induction of relaxation. Some overlaps of mechanisms among the dimensions are discussed. Efficient use of the core characteristics and mechanisms that the present paper has shown must make it possible for researchers to interpret or expect the relationships between cognitive tasks or events and imagery tests.