MENTALIMAGE
Mental image
A mental image is an experience that, on most occasions, significantly resembles the experience of perceiving some object, event, or scene, but occurs when the relevant object, event, or scene is not actually present to the senses. There are sometimes episodes, particularly on falling asleep and waking up, when the mental imagery, being of a rapid, phantasmagoric and involuntary character, defies perception, presenting a kaleidoscopic field, in which no distinct object can be discerned.The above text is a snippet from Wikipedia: Mental image
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