ABSTRACT
In the last 30 years, imagery research has developed in many different directions, with different approaches, methodologies, types of observations, and phenomena. Visuo-spatial mental imagery phenomena may be classified into many different categories, including fantasy, hypnagogic imagery, hallucinations etc. In the present chapter we will focus on the involvement of mental imagery during visuo-spatial thinking. It is well known (e.g., Denis, 1989) that mental imagery can offer critical support to a variety of thinking processes, including spatial reasoning, problem solving using analogical representations, or mental discovery of novel or emergent properties. In order to implement these or similar processes, the human mind often spontaneously generates and manipulates mental images. Such manipulations can be of varying types, including the scanning, zooming, or transforming of images, but all require that the mental image be maintained during the time required for the relative manipulatory operations to be carried out.
