ABSTRACT
Mental imagery occurs when perceptual information is accessed from memory, giving rise to the experience of “seeing with the mind's eye”, “hearing with the mind's ear”, and so on. In contrast, perception occurs when information is registered directly from the senses. Mental images need not be simply the recall of previously perceived objects or events; they can also be created by combining and modifying stored perceptual information in novel ways. Imagery has played a central role in theories of mental function at least since the time of Plato. It has fallen in and out of fashion, in large part because it is inherently a private affair – by definition restricted to the confines of one’s mind. Thus, imagery has been difficult to study. In fact, in 1913 the founder of Behaviorism (the school of psychology that focused solely on observable stimuli, responses, and the consequences of responses), John B. Watson, denied that mental images even existed. Instead, he suggested, thinking consists of subtle movements of the vocal apparatus (Watson, 1913). In spite of the fact that Alan Paivio and his colleagues were able to show that the use of imagery dramatically improves memory (Paivio, 1971), many researchers were not convinced that imagery is a distinct form of thought. Indeed, Watson’s position was echoed 60 years later by Zenon Pylyshyn, who championed the view that mental images are not “images” at all, but rather rely on mental descriptions no different in kind from those that underlie language. According to Pylyshyn (1973), the pictorial aspects of imagery that are evident to conscious experience are entirely epiphenomenal, like the heat thrown off by a lightbulb when you read (which plays no role in the reading process; see also Pylyshyn, 2002, 2003).
