Lives without imagery – Congenital aphantasia

Abstract

Visual imagery is, for most of us, a conspicuous ingredient of everyday experience, playing a prominent role in memory, daydreaming and creativity. Galton, who pioneered the quantitative study of visual imagery with his famous ‘breakfast-table survey’, reported a wide variation in its subjective vividness (Galton, 1880). Indeed, some participants described ‘no power of visualising’. This phenomenon has received little attention since, though Faw reported that 2.1–2.7% of 2,500 participants ‘claim no visual imagination’ (Faw, 2009). The experience of voluntary imagery is associated with activity in fronto-parietal ‘executive’ systems and in posterior brain regions which together enable us to generate images on the basis of our stored knowledge of appearances (Bartolomeo, 2008). The relative contributions of lower and higher order visual regions to the experience of visual imagery are debated (Bartolomeo, 2008). Clinical reports suggest the existence of two major types of neurogenic visual imagery impairment: i) visual memory disorders, causing both visual agnosia and imagery loss, and ii) ‘imagery generation’ deficits selectively disabling imagery (Farah, 1984). In 2010 we reported a particularly ‘pure’ case of imagery generation disorder, in a 65 year old man who became unable to summon images to the mind's eye after coronary angioplasty (Zeman et al., 2010). Following a popular description of our paper (Zimmer, 2010), we were contacted by over twenty individuals who recognised themselves in the article's account of ‘blind imagination’, with the important difference that their imagery impairment had been lifelong. Here we describe the features of their condition, elicited by a questionnaire, and suggest a name – aphantasia – for this poorly recognised phenomenon.