Aphantasia and the unconscious imagery hypothesis.

Mental imagery has traditionally been considered a conscious experience, but recent findings suggest it can occur unconsciously. People with aphantasia, who report no conscious imagery, often perform similarly to controls on imagery-requiring tasks, show imagery-based priming, and exhibit imagery-related neural activity in visual cortex. However, investigating unconscious imagery faces challenges: ensuring imagery is genuinely unconscious rather than unreported due to response biases, and clarifying how imagistic or indirect perceptual processing must be to qualify as imagery. This paper examines the evidence, argues it is less compelling than initially appears, and proposes a strategy for advancing research.

Study at a glance

Abstract

Until recently, mental imagery has largely been regarded as an exclusively conscious phenomenon. However, recent empirical results suggest that mental imagery can also occur unconsciously. People who report having no experiences of mental imagery often perform similar to controls on behavioural tasks thought to require imagery. A surprising number of them also display significant levels of imagery-based priming, and recent neural decoding studies have shown that imagery-related information is being processed in their visual cortex. However, investigating unconscious imagery empirically is not straightforward. One challenge is to establish that imagery is genuinely unconscious as opposed to merely going unreported due to response biases. Another is to clarify how imagistic and indirect perceptual processing needs to be to qualify as imagery. In this paper, we take a closer look at the evidence for unconscious imagery, argue that it is not as compelling as it initially appears, and outline a strategy for advancing research on this question.