Introduction to the special issue on aphantasia

Abstract

Mental imagery has long been recognized as a core component of human cognition. Since the dawn of scientific psychology, it has been associated with memory, imagination, problem-solving, and emotion. The vividness and functional significance of imagery were debated by pioneers like Galton and Binet and the topic has continued to attract attention ever since. In the 1980s, a central controversy in cognitive psychology concerned the nature of the internal representations underlying mental imagery. Two opposing views emerged: one defended a symbolic format – abstract, amodal, language-like propositions (Pylyshyn, 1981) – while the other advocated a pictorial format, in which imagery relies on perceptual-like representations that depict rather than describe experience (Kosslyn, Behrmann, & Jeannerod, 1995). The advent of neuroimaging in the 1990s helped clarify this debate by showing that brain regions involved in mental imagery partially overlap with those recruited during perception (Kosslyn, Thompson, & Ganis, 2006). These findings suggest that mental images are encoded in an analog fashion, closely resembling percepts. However more recently, scientific interest in imagery has been revived by the study of aphantasia, a condition characterized by the absence of voluntary mental imagery. First described by Zeman and colleagues (2015), aphantasia challenges the assumption that mental imagery is a universal feature of human cognition and offers a unique opportunity to reassess its role in both cognitive and emotional life…