This term, Audiation has been covered by the website Wikipedia as part of "Gordon music learning theory" it does not at present have its own enetry
This mediawiki site, a `wiki dictionary` about the nature and practice of free improvisation declines to duplicate the content of that listing. Below there is an introduction - a simple copy and paste. from Wikipedia then a link to the Wikipedia entry.
Introduction, copied from Wikipedia
Audiation is a term Gordon coined in 1975 to refer to comprehension and internal realization of music, or the sensation of an individual hearing or feeling sound when it is not physically present. Musicians previously used terms such as aural perception or aural imagery to describe this concept, though aural imagery would imply a notational component while audiation does not necessarily do so. Gordon suggests that "audiation is to music what thought is to language." His research is based on similarities between how individuals learn a language and how they learn to make and understand music. Gordon specifies that audiation potential is an element of music aptitude, arguing that to demonstrate music aptitude one must use audiation.
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