Order 1332400: Aphantasia

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c o r t e x 1 0 5 ( 2 0 1 8 ) 4 1 e5 2

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Special issue: Research report

(A)phantasia and severely deficient autobiographical memory: Scientific and personal perspectives

Nicholas W. Watkins a,b,c,*

a Centre for the Analysis of Time Series, London School of Economics and Political Science, London, UK b Faculty of Science, Technology, Engineering & Mathematics, School of Engineering & Innovation, Open University,

Milton Keynes, UK c Centre for Fusion, Space and Astrophysics, University of Warwick, Coventry, UK

a r t i c l e i n f o

Article history:

Received 26 February 2017

Reviewed 6 May 2017

Revised 5 July 2017

Accepted 15 October 2017

Published online 7 November 2017

Keywords:

Episodic memory

Severely deficient autobiographical

memory

Mental imagery

Aphantasia

Mind's eye

* Centre for the Analysis of Time Series, L E-mail address: [email protected]

https://doi.org/10.1016/j.cortex.2017.10.010 0010-9452/© 2017 Elsevier Ltd. All rights rese

a b s t r a c t

I address two interlinked aspects of the diversity in our experiences of memory and the

mind's eye. I summarise the long-appreciated role of imagery in mathematics and the

physical sciences, and contrast it with the evidence that some scientists have had limited

or zero imagery. I then recount the story of how I became aware of my own lack of mental

imagery, and the accompanying deficit in my episodic memory, how I have sought sci-

entific understanding of these conditions, and how they have affected my life.

© 2017 Elsevier Ltd. All rights reserved.

1. Introduction

The contributions in this special issue touch on many of the

areas of human creativity in which visual imagery has played

a key role, and my paper, derived from my contribution to the

“Eye's Mind” conference in 2016 supported by the AHRC, aims first to briefly survey the role of imagery in mathematics and

the physical sciences, but it also has a second, more personal

aim.

ondon School of Econom rg.

rved.

Three human visual capacities are so familiar that most

people take them for granted: i) visual imagination in a

“mind's eye”, ii) an “episodic” aspect to memory that travels back in time to give a first person sense of experiencing again

one's own past sights, sensations and emotions, and iii) its opposite, first person “mental time travel” into an anticipated

future. But we really shouldn't be so blas�e. Indeed it has been argued (Tulving, 2002) that episodic memory and the first-

person sense of time are among the most remarkable

ics and Political Science, Houghton St, London, WC2A 2AE, UK.

c o r t e x 1 0 5 ( 2 0 1 8 ) 4 1 e5 242

products of evolution. Because the faculties noted above are

so universal, they can be taken to be essential aspects of being

human, but in the last two years it has become much more

widely appreciated that a significant number of people actu-

ally lack mental imagery (“aphantasia”; Zeman, Dewar, &

Della Sala, 2015), and that some otherwise healthy people

have severely deficient autobiographical memory (SDAM;

Palombo, Alain, Soderlund, Khuu, & Levine, 2015). I am one

such person. I have been aware of my aphantasia and SDAM,

and I have been seeking to understand the reasons behind

them for almost 20 years. The rest of this paper gives a report

of my findings (albeit an unusual one in which first person

testimony will figure large).

2. Scientific aspects

The role of the nearly universal human faculty of mental

imagery (Kosslyn, 1994; MacKisack et al., 2016; Pearson,

Deeprose, Wallace-Hadrill, Burnett Heyes, & Holmes, 2013;

Thomas, 1997) in scientific and mathematical creativity has

long attracted research interest (Brewer & Schommer-Aikins,

2006; Ferguson, 1977; Hadamard, 1945; Mancosu, Joergensen,

& Pedersen, 2005; Miller, 1986; Rocke, 2010). Probably the most

celebrated instance is the physical chemist Kekule's account (Benfy, 1958; Rocke, 2010) of how he dreamt the structure of

the benzene ring: “long rows, … all twining and twisting in snake-

like motion … One of the snakes had seized hold of its own tail, and

the form whirled mockingly before my eyes. As if by a flash of

lightning I awoke; and … spent the rest of the night in working out

the consequences of the hypothesis” (Benfy, 1958). By his own

account, such visualisation was a frequently exercised fac-

ulty, his “mental eye” having been “rendered more acute by

repeated visions of the kind”. The benzene dream was apparently

preceded by an earlier daydream on a London bus about

chemical valence, where “the atoms were gamboling before my

eyes” (Benfy, 1958).

Many physicists have employed visualisation, for example

space scientist Jim Dungey, interviewed in 1986 saying “I saw

the picture … in three dimensions, whereby the electric field over the

polar cap fitted in with the reconnection picture … Then, I think if I

can, everybody can” (Dungey, 1986). Albert Einstein seems to

have been an archetypal visualiser. His most famous thought

experiment, to imagine riding alongside a beam of light, was

conducted as a 16-year old student at a Pestalozzi school in

Switzerland (Isaacson, 2015). Many years later he responded

to a questionnaire about scientific creativity by the French

mathematician Jacques Hadamard [see Appendix II of

Hadamard (1945)] by saying The psychical entities which seem to

serve as elements in thought are … more or less clear images which

can be ‘voluntarily’ reproduced and combined. [Some are] of visual

and some of muscular type. Conventional words or other signs have

to be sought for laboriously only in a secondary stage.”

Pauli even went as far as collaborating with Jung to

investigate the latter's “primordial images” as the bridge be- tween sense perceptions and concepts (Zabusky, 1984). How-

ever, even enthusiastic users of mental imagery have urged

caution. Kekule, after all, warned us to “beware of publishing our

dreams until they have been tested by the waking understanding”.

Although Farmelo (2009) reports that Dirac was “always uneasy

with algebraic approaches to physics and with any mathematical

process he could not picture”, it is striking that he nonetheless

prefaced his “Principles of Quantum Mechanics” by saying:

“the laws of physics do not govern the world as it appears in our

mental picture in any very direct way, but instead they control a

substratum of which we cannot form a mental picture without

introducing irrelevancies” (Dirac, 1930). Although Feynman

greatly admired Dirac, his famous diagrams were a direct

response to the latter's implicit challenge to find a pictorial tool that could be of value in quantum mechanics (Wuetrich,

2010).

The training of physicists recapitulates the historical pro-

cess, and generations of students have struggled with the

transition between Newtonian mechanics and Maxwell's electrodynamics, where many concepts benefit greatly from

visualisation, and quantum mechanics, a theory constructed

using objects as foreign to our direct sensory experience and

intuition as the probability amplitude wavefunction which

solves Schrodinger's equation (e.g., Longair, 2003; Miller, 1986). The rigour exemplified by the scientific method is of course

essential to making science as objective as possible, by

detaching its conclusions from the thought processes of any

one individual, no matter how exceptional, and subjecting

them to experimental test. In mathematics, where proof

rather than experiment is the final arbiter, an even more

fundamental disdain for visualisation has existed in some

quarters. Lagrange for example proudly said “you won't find any drawing in my book”, while the collective of French mathema-

ticians who published as “Nicolas Bourbaki” sought to elimi-

nate any need for visualization, part of a broader distrust of

geometry in proof. In Marjorie Senechal's interview (Senechal, 1998), Bourbaki founder member Pierre Cartier gives this

fascinating reply to her question about the sources of this

disdain: “… The Bourbaki were Puritans, and Puritans are strongly

opposed to pictorial representations of truths of their faith. […] So,

what were the reasons? The general philosophy as developed by

Kant, certainly. […] And then there was the idea that there is an

opposition between art and science. Art is fragile and mortal,

because it appeals to emotions, to visual meaning, and to unstated

analogies. But I think it's also part of the Euclidean tradition. In Euclid, you find some drawings but it is known that most of them

were added after Euclid, in later editions. Most of the drawings in the

original are abstract drawings. You make some reasoning about

some proportions and you draw some segments, but they are not

intended to be geometrical segments, just representations of some

abstract notions. […] The analytical spirit was part of the French

tradition and part of the German tradition. And I suppose it was also

due to the influence of people like Russell, who claimed that they

could prove everything formallydthat so-called geometrical intui-

tion was not reliable in proof.”

In stark contrast to the Bourbaki was a mathematical

visionary (and visualiser) Benoit Mandelbrot, whose own

uncle was one of the founders of the Bourbaki, and whose

life's work was in some sense a riposte to their approach. Describing the way in which he mastered mathematics as a

teenager he said: “I didn't learn much algebra. I just learnt how better to think in pictures because I knew how to do it. I would see

them in my mind's eye intersecting, moving around or not inter- secting and could describe what I saw. Having described it, I could

write two or three lines of algebra, which, is much easier if you know

c o r t e x 1 0 5 ( 2 0 1 8 ) 4 1 e5 2 43

the results than if you don't” (Mandelbrot, 1995). In later years

Mandelbrot's very visual approach enabled him to see deep geometrical links between mathematics and disciplines

including physics, economics and the geosciences that few

people would have connected, but this very farsightedness

seems to have made it difficult for him to explain what he had

seen, Mandelbrot (2012) and some innovations of his from 50

years ago are only now being rediscovered, a process

described by Watkins (2016).

However, the process of science is not just deduction by

individuals but construction by a community. The remarkable

geometric abilities of some blind mathematicians such as

Morin have given insight into the varieties of mathematical

imagination and quite how diverse this community is. Morin

himself noted that “disabilities like blindness, … reinforce one's gifts and one's deficits” and has drawn attention to two sorts of mathematical imagination: “time-like” which deals with in-

formation by proceeding through a series of steps, at which he

was not good, a deficit worsened by blindness, and “space-like”

which allows one to comprehend information all at once, at

which he excelled (Lawrence, 2002).

Much of the work on mental imagery in science has either

concerned naturally strong imagers or people who have lost

sight while retaining (or losing) a “mind's eye”. The famous work of Galton (1880, 1883) recounted by James (1890), thus

remains a particularly important exception. The responses of

some recipients of his questionnaire: “amazed [him]. [He] had

begun by questioning friends in the scientific world, as they were the

most likely class of men to give accurate answers concerning this

faculty of visualising, to which novelists and poets continually al-

lude, which has left an abiding mark on the vocabularies of every

language … ” He was astonished to find that “the great majority

[sic] of the men of science to whom [he] first applied protested that

mental imagery was unknown to them, and they looked on [him] as

fanciful and fantastic in supposing that the words ‘mental imagery’

really expressed what [he] believed everybody supposed them to

mean.” When Galton extended these first approaches to a

larger sample of 100 “men of science”, the majority did not in

fact lack imagery but even so up to six of his respondents

seem to have reported themselves to be truly without expe-

riences of visual imagery. The work of Burbridge (1994) has

made it possible to establish who they were: “(95, Charles Piazzi

Smyth). No power of visualising … (96, Major John Herschel FRS). It

is only as a figure of speech that I can describe my recollection of a

scene as a ‘ mental image’ which I can ‘ see’ with my ‘ mind's eye.’ (97, Sir Edmund Du Cane). No individual objects, only a general idea

of a very uncertain kind. (98, George John Romanes FRS). … My

memory is not of the nature of a spontaneous vision, … ideas are not

felt to be mental pictures, but rather the symbols of facts. (99, Sir

James Paget FRS). … impressions are in all respect so dim vague and

transient, that I doubt whether they can reasonably be called images.

They are incomparably less than those of dreams. (100, Sir J. Henry

Lefroy FRS). My powers are zero. To my consciousness there is

almost no association of memory with objective visual impressions. I

recollect the breakfast table, but do not see it.”

It is striking that James (1890) seems to have completely

accepted Galton's findings, saying that some people “un- doubtedly have no visual images at all worthy of the name, and

instead of seeing their breakfast-table, they tell you that they

remember it or know what was on it. This knowing and

remembering takes place undoubtedly by means of verbal images”.

Faw (2009) argues that both Galton and James may have had

relatively weak imagery themselves. Galton reported that he

could only visualise with effort; saying that “before [he] thought of

carefully trying, [he] should have emphatically declared that [his]

field of view in the dark was essentially of a uniform black, subject to

an occasional light-purple cloudiness and other small variations”

(Galton, 1883). However, after Galton's efforts to “habituat[e him]self to examine it with the same sort of strain that one tries to

decipher a signpost in the dark, [he] found out that this is by no

means the case, but that a kaleidoscopic change of patterns and

forms is continually going on, but they are too fugitive and elaborate

… to draw with any approach to truth.” Even after practise, they

“disappear out of sight and memory the instance [he began] to think

about anything …”, a finding which greatly interested

Hadamard (1945), who was concerned with whether images

accompanied thought or were antithetical to it, as he felt to be

the case for himself. Even Galton's critic, Bain (1880) agreed that there was a “natural antagonism of pictorial aptitude and

abstract thought”.

James' enthusiasm may not have been typical, and Burbridge (1994) notes that Galton's work in general encoun- tered a mixed response among his peers. Galton (1880)

attracted a hostile comment from Bain (1880) almost imme-

diately: “At first blush it seems to be nothing more than a deter-

mination, by accurate statistics, of the relative preponderance of

certain varieties of mind that we already know to exist. … That

certain individuals … have a great or a small visualising memory, is

an important fact as regards them … [but] it contributes nothing new

to science; the existence of such variations has been known at all

times [my emphases]”. Burbridge (1994) shows that Galton was

indeed aware of previous interest in the range of individual

differences from Fechner, Erasmus Darwin and (Wilhelm)

“Wundt of Heidelberg” but it is not clear that they had noticed

the existence of non-imagers before him.

Despite his paper's scathing tone, Bain's plea for a more balanced appraisal remains relevant today: “The ear plays a

part in our intellectual being second only to sight; the power of

language is the rival power to visual conception, and, in the texture

of the memory, may take its place. Something, therefore, should be

known respecting the linguistic memory also, without which no

statement of the intellectual peculiarity of the individual is com-

plete”. Indeed, Paivio's celebrated Dual Coding Theory (Paivio, 1971, 1990, 2007) offers a modern approach to the very

image-word dichotomy that Bain was referring to. It was

characterized by one of my reviewers as “a synthesized view

that is inclusive with both the imaginal and verbal systems playing

prominent roles. … [it] challenges the compartmentalized, either/or

semantic vs. imagery view of cognition and instead advocates a

proposition that the secret lies in the unification of the two great

coding systems for efficacious memory and higher order levels of

cognition”.

The new findings of Zeman et al. (2015), taking up the

enquiry started by Galton, are already giving rise to de-

velopments in many directions. I would like to propose that

one avenue should be to ask how the wide spectrum of mental

imagery among scientists may have affected the evolution of

science itself, informed by the growing awareness that im-

agery can be low or absent as well as strong. I am presently

aware of only a very few documented living aphantasic

c o r t e x 1 0 5 ( 2 0 1 8 ) 4 1 e5 244

scientists or technologists, with perhaps the highest profile

examples being geneticist Craig Venter (Grinnell, 2016) and

software engineer Blake Ross (Ross, 2016). The past is not

much more illuminating, although we do know who Galton's aphantasic respondents were. In view of this paucity of in-

formation, I will give a brief account in the next section of how

I became aware of my own aphantasia, and of my concurrent

SDAM, noting some of the wide variety of published material

which helped me during my search for more insights, and

offering some thoughts on how it has affected me in my work

in physics. I hope that even this limited data point will be of

some value to this nascent area of research. I also think that

an account of how I became aware of my situation in a time

before widespread awareness of SDAM and aphantasia may

already be of some historical and “control” value in itself.

3. Personal aspects

“I saw it in my mind's eye” … “it took me right back” …”where do you see yourself in 5 years' time?”. These phrases are so familiar that most people take for granted the three human capacities

they embody: visual imagination; “episodic” memory that

directly re-experiences one's own past sights, sensations and emotions; and its temporal opposite, first person “mental time

travel” into an anticipated future. Most people, but not all, as

was apparently first noticed by Galton (1880) and is now

becoming clearer through the work of Palombo et al. (2015) on

SDAM and Zeman et al. (2015) on aphantasia. I am somebody

who lacks all these three capacities, and the rest of this paper

is about my quest, both as a physicist and a person, to un-

derstand why, and to come to terms with these differences.

But first, in answer to the reader's inevitable questions, I will try to describe what, for me, it is like to be aphantasic and to

have SDAM, though I must caution that mine may not be

representative of other people's experiences. I think the best way I can describe my aphantasia is to say

that I am unaware of anything in my mind except these cat-

egories: i) direct sensory input, ii) “unheard” words that carry

thoughts, iii) “unheard” music, iv) a kind of “invisible imag-

ery”, which I can best describe as sensation of pictures that are

in a sense “too faint to see”, v) emotions, and vi) thoughts

which seem too “fast” to exist as words. The “invisible imag-

ery” is a sensation of having an image that one feels to be

there but one can't see, as opposed to, say, a faint image like the “misty watercolour memories” of the song “The Way We

Were”. I felt a kinship with the description of his own sub-

liminal imagery by Faw (2009). I see what is around me, unless

my eyes are closed when all is always black. I hear, taste, smell

and so forth, but I don't have the experience people describe of hearing a tune or a voice in their heads. Curiously, I do

frequently have a tune going around in my head, all I am

lacking is the direct experience of “hearing” it. I think the

likely effect of aphantasia on me is to increase my reliance on

the verbal over the visual, and to enhance my interest in the

abstract rather than the concrete. I have an ability to jump

between concepts very easily, but people have commented

that I often forget to explain how these apparently frictionless

leaps happened. I think it may have contributed to making me

more interested in questions than answers, and problems

rather than solutions, because I am always aware of the ca-

veats surrounding an idea, and the different possibilities that

could be adopted, and am not focused on a visual model of

what to do. It does also have some prosaic consequences like

making it harder to orient myself in open country (whereas a

town, rich in shop names, street signs and so on is relatively

easy).

SDAM, meanwhile, is manifest in the way I experience the

past and future. When I think about past events in my life I am

aware that I was there, and frequently aware of details that

are personal, and not told to me by others. I may also be aware

of where people were sitting relative to me, and what colour

their clothes were. I saw the film Vertigo a few days ago, and

still have a sense of the rich redness of the restaurant from the

scene where James Stewart first sees Kim Novak. I have a

feeling that I can form and store some sort of unseen quasi-

spatial memories. What I don't have is the experience that people describe of feeling that they are back in another time

and re-living it. This doesn't mean that I am untroubled by the past or future, quite the opposite, it just means that the past

really is “another country” to which I have no passport. Like A

E Housman I can feel nostalgia for “the land of lost content … the

happy highways where I went, and cannot come again”, but unlike

him I don't “see [the land] shining plain”. It is much harder for me to assess the difference SDAM has made to me compared to

aphantasia. My guess is that its most important effects have

been to do with forward planning, which uses the prospective

memory. This is certainly the potentially affected area that I

feel the greatest actual need to improve. The philosopher

Galen Strawson (Strawson, 2004) has made the interesting

suggestion that some (perhaps most?) people have a strong

sense of themselves as having a continuous “story-arc”, and

has labelled them as “Diachronic”, in contrast with his own

“Episodic” outlook, where “the way I am now is profoundly sha-

ped by my past, but it is only the present shaping consequences of the

past that matter, not the past as such”, very reminiscent of the

Markovian concept in mathematics, where the next state of a

system is only determined by its present one. Importantly, he

notes that this is not identical with what he calls the Narrative

or non-Narrative experience of life, and isn't straightforwardly coupled to whether one has episodic memories or not (as

apparently he does).

I was already 35, and working as a physicist in Cambridge,

when a half-page newspaper column (Bywater, 1997) first

tipped me off about the real meaning of phrases like “the

mind's eye” and “bringing back memories”, which up until then I can only assume I took to be figures of speech. The

author, Michael Bywater, immediately grabbed my attention

by asserting that time is an illusion but you can never tell what's going to do the trick. You don't believe me? Ask any theoretical physicist or better still, an actual physicist if you can find one … but

he won't tell you what the trick is because he doesn't know … If he did […] he'd open a business: time rolled back while you wait”. He went on, brilliantly and concisely, to describe the “state of mind

where the past is not just a collection of memories but a sanctuary,

and you strive to get back there and you can't”, and talk about “the process of Rolling Time Back. You choose a memory, focus on it, let

the rest of the mind go blank, and wait”. I suddenly realized that

not only did I not “see” pictures in my mind, but that I also had

no “Proustian” recall of the type he described: whether

c o r t e x 1 0 5 ( 2 0 1 8 ) 4 1 e5 2 45

pictures, sound, or any other sensory memory. He captured

the quality of episodic memory that William James referred to:

“Memory requires more than mere dating of a fact in the past. It

must be dated in my past” (Greenberg & Knowlton, 2014). When

coupled with projection into one's own future this is the ability that Tulving was one of the first to call “mental time travel”,

seeing it as a quintessentially human ability (Falk, 2008).

What intrigues me most about his piece in retrospect is

that there was nothing exclusively visual about his descrip-

tion, it is as much aural, sensual and textural, as for example

his recall of “the special weight of girls in autumn … when they lean

against you as you walk along”. Nonetheless I was made aware

simultaneously of my total absence of waking visual imagery,

and of the kind of memory that much later I was to learn is

called “episodic”, in a context that immediately linked these

two deficits.

Both for my own personal peace of mind, and because I am

a scientist, I was very curious about these deficits, but for the

next ten years or so much of what I had to go on was the

testimony of my friends, family and colleagues. I fortunately

felt able to talk quite freely to them, but none were aphantasic,

and all reported that they possessed episodic memory. These

sources were supplemented with what I could glean from the

web and occasional glimmers of insight from excellent but

still somewhat tangential books like (Kosslyn, 1994) and

(Schacter, 1996). Because of this scarcity of information,

coming upon Galton (1880) and James (1890) within a year or

two was the key next step for me, and as a physicist I was

naturally intrigued by Galton's conclusion that “scientific men as a class have feeble powers of visual representation”, although I

was finding even from my own first enquiries that this was not

the case among the present-day scientists I spoke to, and a

careful re-analysis of his own data does not really substanti-

ate his view (Brewer & Schommer-Aikins, 2006). Importantly,

Galton's work explicitly linked imagery and memory, and was thus of relevance to both my deficits, though I tended not to

distinguish them initially and simply thought of them as a

missing “visual memory”. Unfortunately I didn't start keeping a diary, but I think my overwhelming reaction was to wonder

why I had never encountered this aspect of his work, espe-

cially because as a physicist I was aware of many of his pio-

neering contributions to statistics, although I understood that

his role as a founder of eugenics has made him an unavoid-

ably problematic figure.

I could have stopped my enquiry right there in the late 19th

century, but the natural immediate question was what had

happened to this field of research since then, and whether a

fuller scientific explanation of my situation now existed. I

soon encountered the account by Thomas (1997) of the

“iconophobia” of J B Watson and Knight-Dunlap, and reports

of how, after early progress like the Columbia University PhD

thesis by Betts (1909), the scientific study of mental imagery

had experienced a very long eclipse in the first half of the 20th

century before the renaissance later confirmed to me by other

sources such as Mancosu et al. (2005), MacKisack et al. (2016)

and Keogh and Pearson (2017). I was intrigued by the sugges-

tion that Watson may have been aphantasic (Faw, 2009)

though this is clearly a contested point (Thomas, 1997). I was

struck, however, by the relative sparseness of available in-

formation, and sympathized with the view of Thomas (2014)

in a post originally written for the Psyche-D forum in 2001:

“so far as I have been able to discover (and I have looked, and have

asked those who might be expected to know), although the existence

of people who deny having visual imagery has been known to science

for well over 100 years (Galton, 1880, 1883), no systematic research

whatsoever has been done on the phenomenon.”

Over the next 10 years or so my incessant web searches

and the growing volume of online archived papers in

neurology, philosophy, and other relevant disciplines led me

to more clues, though I found much more related to imagery

than to memory. The appearance of online discussions con-

taining non-imagers' own testimony was undoubtedly important to me, particularly one at the Psyche-D forum [later

digested at web pages maintained by Thomas (2014)]; one

moderated by philosopher Tony Birch (Birch, 2003); and a third

responding to a blog post by Schmidt (2010), not least because

they were the first reassurances I received that my experience

was probably relatively common. An example is the account

of Jim Jablonski, one of the earliest posters to (Birch, 2003): “My

consciously projected images seem to wash out in the glare of my

conscious mind … I am not looking to be cured. I find it hard to believe

that no one has studied this image problem and hasn't given it a nice Greek name”.

However, for various reasons I “lurked” rather than taking

part in forums, not least of which was a concern about how I

might be seen professionally in my own field of physics,

having already been rather more open on the subject with

colleagues than was perhaps entirely prudent. I was also

concerned about the ethics of leading other people to realise

they have a possibly unchangeable memory deficit (as

opposed to an imaging one). Even now I am still not sure how

useful this self-knowledge is, but the widespread public dis-

cussion of SDAM and Aphantasia has made the point rather

moot.

In the absence of any obvious interest from modern sci-

ence, and because of the intrinsically cross-disciplinary na-

ture of the topic, I was very eclectic in my reading. One

intriguing pointer was to a self-taught inventor from the

counterculture, Wally Minto, who was already, in the 1970s,

very aware of different visual and non-visual modalities of

thought, and tailoring his “alpha awareness” training to them

(Mangum, 2001). Instances in art included a song, “No mind's eye” (Mecca Normal, 2002), by a Canadian art rock band in

which songwriter Jean Smith talks about her father's pro- fessed aphantasia, again linking it to memory: “look down at

your hands, can you see them when you were small, picking rasp-

berries”. She also recently wrote a novel (Smith, 2014) in which

a painter, Gordon, “does pink and orange abstracts that he allows

his son Frank to name. The paintings don't have a basis in reality until young Frank decides what they depict. This is unnerving to

Gordon who claims not to have a mind's eye”. Another aphantasic character in fiction is the male protagonist of the novel “Lying

in bed” (Landis, 1995).

Eventually, though, I did start to come across relevant

modern scientific work, in part because I was starting to find

the right keywords. An important example was the “visual

memory deficit amnesia” of Rubin and Greenberg (1998).

Despite the intriguing title, the patients described in this

paper were not like me but instead had developed amnesia

due to a brain injury. However it did offer me significant

c o r t e x 1 0 5 ( 2 0 1 8 ) 4 1 e5 246

evidence for a link between image and memory, because of

their finding that the loss of imagery appeared to have such a

powerful effect on the ability to re-experience episodes. It also

gave me an interesting example of a recent scientific paper

quoting Galton (1880) as evidence for its assertion that: “many

individuals with no known neurological damage report that they do

not experience visual images while awake”. Over time I encoun-

tered various other relevant imaging studies such as that of

Cui et al. (2007), in which fMRI was used in concert with Marks' Vividness of Visual Imagery (VVI) score, and in which indi-

vidual differences in vividness were quantifiable. Another

interesting example is Logie, Pernet, Buonocore, Della Sala

(2011) whose work was informed by the Zeman et al. (2010)

study of Patient MX, who had lost the subjective experience

of imagery after an operation, but who retained the ability to

perform many of the tasks that he would have previously used

it for.

With hindsight the public discourse was in a strangely

divided state, as realised at the time by Brewer and

Schommer-Aikins (2006) who noted that there was a sub-

stantial continuing literature that accepted, and even ampli-

fied, Galton's claims both generally and as they applied to scientists (including James (1890), Paivio (1971) and Kosslyn

(1980)), even as another literature (e.g., Ferguson, 1977)

dwelt, as I have done in the previous section, on self-reports of

how “imagery has played an important role in the thinking of many

great scientists”. They did, however note that Galton's ques- tionnaire did not distinguish clearly between imagination and

memory.

After about 7 years I began email approaches beyond my

immediate circle, which at first either drew no reply, or pro-

fessions of scepticism. While not unkind, they were not very

encouraging either, so the next real breakthrough for me came

in 2009 when I found the work of Bill Faw, the first aphantasic

person I communicated with, who had just published an

excellent review (Faw, 2009) from a standpoint somewhere

between the philosophical and neurological that was

informed very much by his own experience. His surveys of a

total of 2500 people are the source for his widely quoted (e.g.,

Zeman et al., 2015) but provisional estimate that as many as

2% of the population may be aphantasic, a finding similar to

that of Betts (1909). His situation was ostensibly exactly like

mine in that he had no visual imagery, willed or otherwise, as

he recounted well in the review: “I close my eyes, I see nothing. I

silently think, silently read, with no voice. I'm haunted by silent tunes. When asleep I have frequent vivid and occasionally lucid

dreams in all sensory modalities.”

The next key step was finding Oliver Sacks' account (Sacks, 2007) of how taking amphetamines in the 1960s had tempo-

rarily changed the nature and extent of his own very weak

voluntary imaging abilities. “I … could hold very accurate and

stable visual images in my mind and trace them on paper, as with a

camera lucida. … My enjoyment of these newfound powers … was

mitigated, however, by finding that my abstract thinking was

extremely compromised. When, decades later, I read of Bruce Miller's patients and of Allan Snyder's experiments, I wondered whether the amphetamines might have caused a transient temporal lobe disin-

hibition”. It raised the intriguing possibility that I might indeed

be able to “switch on” the imagery by some means-though not

amphetamines !-with the obvious corollary of wondering

whether this would give me a capacity to experience episodic

memory, but damage my ability to think abstractly which is

rather essential for my work in theoretical physics. I

wondered if a form of temporal lobe inhibition might be a

physiological or psychological explanation for my own expe-

rience, and, if so, what could have given rise to this.

More immediately, Sacks' writing on his experience spur- red me to email him in 2010. Receiving a handwritten reply

from him that included his New Yorker article “The Mind's Eye” (Sacks, 2003), which by then he was expanding into the

last chapter of a book (Sacks, 2010), was deeply inspiring and

touching and played a major part in motivating me to stay on

the trail. He told me that “I'm very much a non-imager and I suppose a verbalizer myself. I would score zero with every item in

Galton's questionnaire, but-somehow-I seem well able to describe events, even enabling others to picture them vividly. I still have a

fairly strong episodic memory-I do not know how to account for these

apparent contradictions.” I was however very puzzled by the

paradox that he highlighted, of his being aphantasic in the

strict (i.e., voluntary) definition of Zeman et al. (2015) and yet

possessing an episodic memory, as I was already quite sure I

completely lacked one.

Sacks' reference to episodic memory seems to have prompted me to distinguish more clearly between imagina-

tion and memory. Prompted in part by this, the final “Eureka”

moment for me was when I came across Endel Tulving's seminal work on the distinction between episodic and se-

mantic memory, and the stories of amnesic patients Henry

Molaison (HM) and Kent Cochrane (KC), both now deceased, in

late 2010, thirteen years after reading Bywater. This time I

didn't fail to see the importance of episodic memory, and my web searches about Tulving quickly revealed that he had

already predicted in an interview on the Science.ca website

[later published in (Shell, 2006)] that otherwise healthy people

without episodic memory should exist: “animals like his cat

have no episodic memory …. and he believes that some perfectly

intelligent and healthy people also lack the ability to remember

personal experiences. These people have no episodic memory. They

know, but do not remember. Such people have not yet been identified

but Tulving believes, they soon will be”. This distinction between

re-experiencing the past and just “knowing the facts” was

amusingly emphasised on the website by a cartoon (Fig. 1)

where Tulving is interrogating a cat.

I wrote to him in January 2011, and although he was

essentially retired from research, he directed me to his

colleague Brian Levine, and Brian's then PhD student Daniela Palombo, at the Rotman Research Institute in Toronto. I went

to Toronto for a week in the summer of 2011 for the tests re-

ported in their paper on 3 individuals with SDAM, including

me (Palombo et al., 2015).

When it appeared Palombo et al. (2015) had several pieces

of evidence about what is happening in my brain, and those of

the other two people they tested, when we remember -or

more correctly, what is not happening in my brain when we

don't remember-the neurological “dogs that didn't bark”. The most striking evidence is from EEG: the absence of an evoked

response potential at 500 msec during successful recognitions

that is present in control subjects and associated with re-

experiencing. Our recognition is intact, but is thought to be

achieved by non-episodic processes.

Fig. 1 e Endel Tulving and the cat (drawing by the late Ruth

Tulving).

c o r t e x 1 0 5 ( 2 0 1 8 ) 4 1 e5 2 47

Additional evidence included the clear visual memory

deficit seen on one specific neuropsychological and experi-

mental task, which was, however, the only obvious area of

impairment in terms of behavioural assessment. The test was

the Rey complex figure test related to sketching a complicated

line drawing from memory (Rey, 1941). All of us had a reduc-

tion of about 10% in the right hand hippocampal volume,

though this was small compared to developmental amnesics

who normally show bilateral reductions of order 30e50%

(Varga-Khadem et al., 2003). The investigators' questionnaire showed the demonstrable relative sparseness of our recol-

lected autobiographical detail especially for decades-old

memories. Finally, fMRI data showed that some regions

known to be associated with autobiographical memory were

less activated, including the medial portion of the prefrontal

cortex and within the temporal lobes. The reduced activity in

the praecuneus is notable (Daniela Palombo, personal

communication), because this area may be relevant to the

mental imagery component (Cavanna & Trimble, 2006;

Fletcher et al., 1995). As well as the three SDAM cases they

studied, Palombo et al. (2015) referred to two previous cases

with a similar profile discussed by (Greenberg & Knowlton,

2014). In addition, although interpreted within the lesion

literature, the patient reported in (Botez, Olivier, Vezina,

Botez, Kaufman, 1985) seems to have many of the attributes

of aphantasia and SDAM.

I was initially surprised that one other of the three SDAM

cases, Susie McKinnon, in her various interviews concurrent

with the publication of the paper (e.g., Branswell, 2015)

described an even starker personal experience of episodic

memory absence than I do. On reflection, however, I can only

assume that, as one would expect, SDAM has degrees of

“severity”. The division between semantic and episodic

memory has recently been supplemented by the intermediate

idea of “personal semantics” (Renoult, Davidson, Palombo,

Moscovitch, & Levine, 2012), which perhaps I am using more

than she does. I do certainly feel I often have something in

memory that is at the same time stronger and more personal

than a semantic fact and weaker than the full-blown episodic

recall experience. I certainly don't feel that I am “living life in the third person” (Baycrest, 2015), or “stuck in time”, and would

concur with the view of Craver, Kwan, Steindam, and

Rosenbaum (2014) that more needs to be done to tease out

exactly which aspects of temporal consciousness are affected

by episodic deficits. It may be that part of the resolution of this

puzzle lies in other models such as Paivio's DCT, and that my own consciousness is simply more verbal than visual. It

certainly feels this way. However, words, smells, or even

music clearly don't trigger the kind of episodic recall in me that so many people describe, even though they can certainly

generate a kind of wistful nostalgia.

The publication in early 2015 of the Rotman study was a

personal milestone for me, but only a few months later it

was followed by a complete surprise-the Zeman et al. (2015)

paper on Aphantasia in this journal [although I had seen

their Zeman et al. (2010) study I had never got in contact].

One immediate result has been a great increase in the

amount of personal testimony on the web about lifetime

imagery deficits, from people who recognise aspects of their

own experience. I cannot do justice to this explosion here,

and the reader is encouraged to explore for themselves in

the many new forums, web pages, videos etc. already

devoted to aphantasia (and SDAM). One thing that has

become clear from (Zeman et al., 2015) and the more than

10,000 responses the Exeter team have now received is that

some but not all aphantasic people have memory deficits

(Zeman, 2016). This implies that Aphantasia and SDAM are

not exactly the same, but poses a question: Is SDAM a subset

of “voluntary” or “total” aphantasia, i.e., is the absence of

voluntary (or both voluntary and involuntary) imaging a

necessary, but not sufficient, condition for SDAM? At least in

principle one could have intact imagery but be deficient in

episodic memory (Adam Zeman, personal communication),

and indeed there have certainly been cases where people

lost episodic memory as a result of injury, having previously

had it, and yet reportedly kept their mental imagery. One

such example is patient KC whose ability to visually imagine

things … [was] intact” after the motorcycle accident that

severely damaged his episodic memory (Tulving, 2002). But

SDAM, like aphantasia, is more narrowly defined, as a life-

long deficit in otherwise healthy people, and I haven't yet seen published reports of people who have that kind of

memory deficit innately without also having a deficit in

imagery, although I have seen (and mislaid) a self-report in a

Tweet by one such individual. It is important to stress here,

c o r t e x 1 0 5 ( 2 0 1 8 ) 4 1 e5 248

though, that I am not personally aware of to what extent the

key tests of autobiographical memory in aphantasia, and

visual imagery in SDAM, have yet been done.

A schematic (Fig. 2) illustrates one possible way in which

aphantasia and SDAM could differ. As early as 1909 Betts was

stressing that “voluntary imagery … the ability to call up certain

specified images at will”, the focus of much of Galton's interest, was distinct from “spontaneous imagery … the normal functioning

of imagery in the mental process”, and noting that a failure to

distinguish them had introduced “a certain haziness”. As orig-

inally coined by Zeman et al. (2015), the term Aphantasia only

denoted the absence of voluntary images (the outermost ring

of Fig. 2). This definition would seem to apply to Oliver Sacks.

As well as his inability to visualize voluntarily, of which he

became aware aged 14 when talking to his mother, a surgeon

and strong visualizer (Sacks, 2003, 2010), he seems, however,

to have been aware of a sparseness in, and possible unreli-

ability of, his memories by his late teens, saying (Sacks, 2001)

that the “memory hole” in Orwell's 1984 resonated with his own doubts about his memory and “led to an increase in [his]

own journal keeping, and photographing, and an increased need to

look at testimonies of the past”. It seems clear that this very

active personal episodic compensation contributed to the

millions of words of personal journal that are mentioned in

(Sacks, 2015). However, he seems to have been no stranger to

involuntary images, describing them in association both with

his own memory of, and his brother's account of, two wartime bombs both in an interview (Silberman, 2002), and in the New

York Review of Books (Sacks, 2013): “I can see the bomb in my

mind's eye now, Pa with his pump, and Marcus and David with their

Fig. 2 e A tentative heuristic diagram illustrating one of

several possible ways in which aphantasia and SDAM

might be related. It distinguishes between voluntary

aphantasia, defined as a lack of voluntary imagery as was

originally done in Zeman et al. (2015); and complete

aphantasia when both voluntary and involuntary imagery

are absent. I have placed SDAM, defined purely in terms of

episodic memory, in the centre, which corresponds to the

possibility that complete aphantasia might be necessary

for SDAM. If, for example, there prove to be people who

have SDAM but don't lack voluntary imagery, this diagram will need to be modified.

buckets of water. How could I see it so clearly if I wasn't there?”.

Indeed, he described the “resonant clonk” of a piece of Tungsten

sent by the chemist Roald Hoffmann as serving “as a sort of

Proustian mnemonic, [that] instantly brought Uncle Tungsten to

mind … Other pictures rose immediately in my mind … the mem-

ories, now started, continued to emerge, … many forgotten for fifty

years or more.”

The kind of complete Aphantasia that has evidently reso-

nated with many peoples' experience, including mine, corre- sponds to the absence of both voluntary and involuntary

imagery, the next ring in the diagram. I think it would be

useful to more routinely distinguish between these two defi-

nitions as I have done on the schematic, as there have been

assertions that such a total absence of imagery may preclude

episodic memory altogether. For example, when Greenberg

and Knowlton (2014) studied “two people who had no visual im-

agery [they] found [them to] not only [have] a deficit of visual im-

agery [but also] an auditory-imagery deficit and a near-complete

inability to relive their memories”. I have retained SDAM as a

third category, but I am thus unclear as to how strong the

distinction between it and complete aphantasia is. One key,

testable, question here is whether aphantasics who report

episodic memories always have them accompanied by im-

ages, or whether there is some other nonvisual way of

accessing such memories.

After the insights from the combined findings of Palombo

et al. (2015) and Zeman et al. (2015) and the surge of per-

sonal testimony that has resulted, one remaining question

that I would like to clarify is that of dreams. I am almost

certain that I have images in dreams, although my inability to

recall them because of the absence of waking imagery makes

it impossible to be sure. Clearly some others with aphantasia

do so as well, from their accounts. The lingering possibility of

a psychological origin for some cases of aphantasia (de Vito &

Bartolomeo, 2015; Zeman, Dewar, & Della Sala, 2016) means

that I would like to be sure that my conscious imagery is not

being repressed, although the SDAM paper stated that “there is

no evidence to support a neurological or psychiatric explanation ” for

their findings. Dreaming and voluntary imagery are likely to

involve very different circuits (with some overlap) e dream

imagery is generated “from below”, by activity in the brain

stem (e.g., Leu-Semenescu et al., 2013), whereas voluntary

imagery is likely to depend on the fronto-parietal cortical ex-

ecutive system (e.g., Zeman et al., 2015; Bartolomeo, 2008), so

the dissociation isn't greatly surprising (Adam Zeman, per- sonal communication). But it is still unclear to me how a

dream can have access to images of people that I know, but

can't visualise while awake, something that I am almost sure has happened to me. On the face of it the dream is either

accessing otherwise unavailable visual memories, or is

randomly generating faces that I am “recognising”, or

believing (in the dream) that I recognise. I am not sure how

one could test between recall in a dream and “mere” recog-

nition, and would urge that consideration be given to this.

4. Conclusions

I have briefly reviewed some of the literature that exists on

mental imagery in science, and noted that the faculty has

c o r t e x 1 0 5 ( 2 0 1 8 ) 4 1 e5 2 49

always been both widely used and treated with caution.

However, Galton's finding that some scientists had extremely limited or zero imagery raises questions about the influence

this other pole has had on the evolution of science and

mathematics which I think should be revisited in the light of

the new evidence from Zeman et al. (2015) about aphantasia. I

have recounted my own experience of becoming aware of my

aphantasia and a concomitant memory issue, SDAM, and the

work of Palombo et al. (2015) in providing objective evidence of

the latter. My participation as a research subject for their

paper provided me with gratifying empirical evidence that

what I thought was happening was indeed real, but, equally,

confirmed that it is limited in its scope, and hasn't stopped me living an essentially normal life. It was also satisfying to have

made some contribution to science beyond my own enjoyable

but limited achievements in physics. I would like to conclude

by considering two final points. One is the question of how

aphantasia has affected my own science, and the other is how

after all this, do I feel about aphantasia and SDAM, what in-

sights have I gained that help me and might help others, and is

there anything more I can do?

My scientific career started with a degree and then PhD in

theoretical physics. I thus need to be able to reason abstractly,

and to communicate with other scientists, but evidently don't need to be able to picture things. I think with hindsight the

influence of aphantasia can be seen in the courses which I

preferred. I found quantum mechanics and statistical me-

chanics to be much more congenial than for example electro-

magnetic theory, and as a graduate student I particularly

enjoyed the third volume of Feynman's lectures in which he developed quantum mechanics almost entirely from consid-

ering an abstract spin. Transitioning into space science as a

postdoc, and working in the environmental sciences, pre-

sented some challenges, particularly in dealing with the

widespread use of two-dimensional colour plots, which

speakers frequently want their audience to compare with

previously shown ones which I now assume they expect peo-

ple to recall. A growing understanding of my thinking style has

since helped me to work with colleagues, especially Sandra

Chapman who is a strong visualiser and enjoys precisely those

spatial, 3-dimensional areas of physics that didn't appeal to me. My collaboration with her began when she saw a computer

screen displaying a simulated trajectory from a quantum me-

chanical problem I had studied in my PhD, that had the same

form as problems in electromagnetic theory that she was

interested in. The equations came only later. I also wonder if

the fact I lost interest in chemistry at school about the same

time as we started doing organic chemistry may have had

some connection to my inability to visualise complex mole-

cules. Oliver Sacks' deep love of chemistry (c.f. Sacks, 2001) might seem to caution against such an interpretation, but

apparently he was much more interested in inorganic chem-

istry than organic (Kate Edgar, personal communication).

Even 20 years on, I am still ambivalent about my awareness

of aphantasia and SDAM. For a long time I felt that I would

have been happy to leave the apple on the tree of knowledge,

as it were, and go on as blithely unaware of these issues as I

had been for most of my life. The most touching expression of

the frustration I sometimes feel from this loss of innocence

came from Mcalpine (2016): “So … if I had a neurotypical mind's

eye, I could do this too? I would be able to see pictures of my [family

and] … friends, like a slideshow or even a movie? … How healing that

would be if I were sick, or when I become old in body and afraid. I

allowed myself to weep at this terrible loss of something that (as far

as I know) I have never had. I let rip with delicious self-pity for two

minutes. That's more than enough”. I can only aspire to her self- discipline, or the sense of wonder at his own aphantasia

shown by Blake Ross, a founder of Firefox (and screenwriter): I

think what makes us human is that we know we're the galactic punchline but we can still laugh at the set up. The cosmos got me

good on this one. How beautiful, though, that such electrical epiph-

any is not just the province of the child.” (Ross, 2016).

After many years seeking clues in relative isolation, my

contacts with Sacks and Faw, and then being a research subject

in a careful and thorough scientific study on a small sample, the

dizzying explosion of new knowledge and testimony resulting

from the widespread publicity about aphantasia left me reeling

for a while, feeling rather like one of the starship travellers in a

favourite science fiction novel from my childhood (Heinlein,

1963). After years of dangerous voyaging between a handful of

stars in the (relatively) near neighbourhood of the sun, the

greatly depleted crew is picked up by people who have now

found out how to travel faster than light and can return them to

earth in an afternoon! But I eventually came to realise that if I

had to become aware of it at all I am glad I pursued the subject

myself, and that I didn't become aware of it only just recently from the attention surrounding the SDAM and aphantasia pa-

pers. I think this is because although I do indeed feel SDAM as a

deficit, and a difference, I am ambivalent about the presump-

tion some people have leapt to that both it and aphantasia must

automatically be disabling. In particular even my own career

suggests that it isn't true that aphantasic children must be at an educational disadvantage (Costandi, 2016). I rather think that

theway I havehad tocompensatefor aphantasia and SDAMhas

been at the root of many of my talents as well as my limitations,

and indeed my semantic memory has been something I have

been able to rely on for most of my life.

I am though still left with one of the questions that origi-

nally motivated me, what else, if anything, can I do to

compensate for my deficits? In my case the answers are

different for SDAM and aphantasia. Visualisation is some-

thing that I don't really experience as an absence, it is rather something I am simply curious about, much as one might

wonder what it might be like to be of a different gender, or live

in a different era. I am intrigued by anecdotal reports of people

increasing their imaging ability, including for example some

postings to (Birch, 2003), and I know that some aphantasics

that I and others have spoken to are keen to do this. As far as I

know, though, the conclusions of Rademaker and Pearson

(2012) typify a current academic consensus that voluntary or

involuntary imagery probably cannot be increased from its

total absence, as opposed to being increased when already

present. I share the ambivalence expressed by Grinnell (2016)

about having such a faculty returned to me after its absence

for so long, and would want to be able to “switch it off” if I

didn't like having it. Whether this consensus changes, or new technological prosthetic aids rather like those of the Black

Mirror episode “The Entire History of You” (Brooker, 2011)

appear in my lifetime, will be one of the developments I am

most curious to see.

c o r t e x 1 0 5 ( 2 0 1 8 ) 4 1 e5 250

SDAM, however, remains rather different, and my memory

deficit really does sometimes feel like an absence or loss. I

understand the surprise that many people clearly feel when

told that it apparently isn't necessary to have the experience of first person, visual, emotional “mental time travel” into

one's own past and future in order to be human. SDAM really doesn't seem to disconnect me from my past and future as much as one might expect, however, consistent with the ar-

guments of Craver et al. (2014). Palombo et al. (2015) put it well

when they said people with SDAM “experience the past in the

absence of recollection”. I am still very much a product of my

own past, it's just that I can't subjectively go back there. A good example of what I do have is my experience of seeing Holst's St Paul's suite performed in London on a (Puffin Club) school outing in the early 1970s. I have no emotion-laden episodic

memory of being there, but nonetheless somehow know that I

found it joyous, and feel that it helped me towards a lifelong

love of classical music. As far as I understand the meaning of

Renoult et al.'s “personal semantics” this memory is of that type, in that the event was personal rather than shared with

other family members.

An awareness of SDAM has made some things I already

had more precious to me. Family photograph albums, or my

own sketches in the scrapbooks I compiled as a spaceflight-

obsessed teenager, have come to replace an episodic mem-

ory by in some sense becoming the memories. I have also been

fortunate to live at a time where both a personal and a global

episodic memory have become available artificially from

technologies like smartphone cameras and YouTube. I have

for example searched for a remembered fragment of a lyric in

order to find a TV show credit sequence last seen when I was a

child. The web has also been a great boon in its ability to find

evidence that something did indeed happen as I think I

remembered it, for example live recordings from concerts I

went to decades ago.

I have now started to be more proactive in working around

my memory deficit, by using a tool that Oliver Sacks recounted

to us when Sandra Chapman and I finally met him in New York

in 2014. He was at that time working on the last volume of his

memoirs (Sacks, 2015) and told us how he had found that

dictating them during a long car journey around North Amer-

ica had helped him to recall episodes. Using sound recordings

of my talks and interviews (and their transcriptions) has been

useful, not only by prompting recall of forgotten details but to

try and relive the associated enthusiasm and energy.

I was also intrigued by the technology of video lifelogging

by wearable cameras. The pioneering Sensecam from Micro-

soft Research which was used in trials by amnesia researchers

(Laurson, 2009) was followed by commercial offerings such

the currently unavailable Autographer and Narrative Clip. I

was tempted, but the latter's dependence on cloud storage, and possible antipathy from the public due to lack of famil-

iarity with such devices, were two factors that have stopped

me so far, though I hope the technology will return in some

form. Something like the combination of the Narrative Clip

with Google Glass that was investigated by NYU Stern school

(Mishkin, 2015) could be a remarkably appealing asset.

Perhaps one day prosthetics like this will seem no more

remarkable than the spectacles that I have worn since about

the age of 6.

In the end, though, all of us try to transcend whatever fate

has placed in our way, and I am aware of what a fortunate life I

have in fact had. I would thus like to end with some words that

have inspired me. On aphantasia, I feel that the beautiful

summing up from Sacks (2003) conveys how there is much

more to imagination than mental imagery: “Such powers may

be invaluable, but [they are ] … utterly different from the higher and

more personal powers of the imagination, where there is a continual

struggle for concepts and form and meaning, a calling upon all the

powers of the self. Imagination dissolves and transforms, unifies and

creates, while drawing upon the “lower” powers of memory and

association. It is by such imagination, such “vision,” that we create

or construct our individual worlds. At this level, one can no longer

say of one's mental landscapes what is visual, what is auditory, what is image, what is language, what is intellectual, what is

emotionaldthey are all fused together and imbued with our own

individual perspectives and values.” This resonates strongly with

the perspective of many of the artists who responded to Susan

Aldworth on the subject of aphantasia (Aldworth, 2016).

Strawson (2004), meanwhile, quotes the 3rd Earl of Shaf-

tesbury [1671e1713] to remind us that we are not just our

memories (square brackets indicate his interpretations): “The

metaphysicians … affirm that if memory be taken away, the self is

lost. [But] what matter for memory? What have I to do with that

part? If, whilst I am, I am as I should be, what do I care more? And

thus let me lose self every hour, and be twenty successive selfs, or

new selfs, ‘tis all one to me: so [long as] I lose not my opinion [i.e., my

overall outlook, my character, my moral identity]. If I carry that with

me’ tis I; all is well…. e The now; the now. Mind this: in this is all.”

And the last word is from Sandra Chapman, written while

she was contemplating the sea at St Ives, Cornwall, and

thinking about the many and diverse ways we can aggregate

our past and present experiences to make the selves we carry

forward into the future:

All of the oceans I have seen

are in this ocean, in between

each wave, each sigh, a thousand lands

a thousand dreams and miracles

Acknowledgements

I am grateful to my partner Sandra Chapman, my parents,

brother and sister and many other people for their help and

encouragement during my investigations, in particular Andy

Bereza, Ed Bullmore, Michael Bywater, Matt Coles, Ed Collier,

Colleen Cotter,Daniel Crow, SarahDelfont, Kate Edgar, Bill Faw,

Sarah Jane Hall, Henrik Jensen, Caroline Lambard, Brian Levine,

Nick Moloney, Bill Nuttall, Charles Ogilvie, Daniela Palombo,

Mike Pinnock, the late Oliver Sacks, Endel Tulving, Paul War-

wick, Adam Zeman, and all the participants who made the 2016

Eye's Mind meeting such a rich and valuable experience.

r e f e r e n c e s

Aldworth, S. (2016). The art of imagination, talk slides from presentation at “The Eye's Mind”. http://medicine.exeter.ac.uk/

c o r t e x 1 0 5 ( 2 0 1 8 ) 4 1 e5 2 51

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