An Epidemiological Study of Aphantasia

Abstract

Aphantasia is a newly acknowledged condition characterized by the inability to form mental images in one's mind's eye. As it has recently surfaced, there has been little research conducted on it. I created a survey and distributed it to groups of self-declared aphantasiacs via social media, and received 395 responses. These responses were compared to a control group of 150 subjects. This epidemiological study of aphantasia is the first of its kind to function on a large scale, providing important information about the nature of the condition and its effects on those who have it. The results suggest that aphantasiacs find mental workarounds to compensate for their lack of visualization skills that allow them to be high-functioning as individuals and in society. One of the most prominent results is that most aphantasiacs have vivid visual dreams, suggesting that aphantasia affects conscious, but not unconscious visualization. Another important result lies in the fact that most aphantasiacs experience diminished imagery of their other senses, not simply visual; i.e., they have difficulty conjuring auditory or gustatory imagery. This suggests that aphantasia is caused by a neurological mechanism broader than those responsible for just visual imagery formation and recall.

Full text

An Epidemiological Study of Aphantasia
By: Melody Munitz

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Abstract
Aphantasia is a newly acknowledged condition characterized by the inability to form
mental images in one’s mind’s eye. As it has recently surfaced, there has been little research
conducted on it. I created a survey and distributed it to groups of self-declared aphantasiacs via
social media, and received 395 responses. These responses were compared to a control group of
150 subjects. This epidemiological study of aphantasia is the first of its kind to function on a
large scale, providing important information about the nature of the condition and its effects on
those who have it. The results suggest that aphantasiacs find mental workarounds to compensate
for their lack of visualization skills that allow them to be high-functioning as individuals and in
society. One of the most prominent results is that most aphantasiacs have vivid visual dreams,
suggesting that aphantasia affects conscious, but not unconscious visualization. Another
important result lies in the fact that most aphantasiacs experience diminished imagery of their
other senses, not simply visual; i.e., they have difficulty conjuring auditory or gustatory imagery.
This suggests that aphantasia is caused by a neurological mechanism broader than those
responsible for just visual imagery formation and recall.
Introduction
Visualization, or being able to conceive an image in one’s mind’s eye, is an impressive
and impactful ability. Believed to be the product of frontoparietal and posterior brain processes
(Bartolomeo, 2008), this skill has numerous practical implications, such as its assistance in
learning, glancing ability and creativity, among other psychological processes. The formation of
mental imagery is also linked to memory, as supported by Marks’ 1973 experiment in which
male and female subjects who claimed to have varying visual imagery capabilities were shown
an image and then asked to recall it. The results suggested that the subjects who claimed to have
higher visual imagery capabilities were more accurate in their recall of the images they had seen,
allowing for the conclusion that “images have an important role in memory” (Marks, 1973). In
another experiment relating to the correlation between eye movements and visualization, there
was “no evidence that vivid visualizers showed more scanning activity than a group of Ss
[patients] operationally defined to be poor at visualizing”, suggesting that visual imagery is more
than simply eye movements (Marks, D.F., 1973).

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Some of the first documented research regarding visual imagery was conducted in 1880
by Sir Francis Galton, esteemed English scientific pioneer of the 19th century, and was geared
toward determining how different people's visual imagery skills compare. To assess where each
patient lay on the scale of visualization, Galton developed the Vividness of Visual Imagery
Questionnaire (VVIQ), which has since become a standard of scientifically quantifying
visualization skills. This questionnaire describes several situations and then asks the participant
to rate the vividness of their mental imagery on a scale of 1-5. Using the VVIQ and other similar
tools and questionnaires, Galton found that not everyone is equipped with comparable visual
imagery capabilities. While most people fall somewhere on the high end of the spectrum, having
good or even superb visual imagery skills, there is a small percentage of people that possess very
poor visualization abilities (Galton, 1880). In similar research conducted by Faw in 2009,
assessing such capabilities of 2,500 participants, it was found that 2.1-2.7% of them fell in this
small group, claiming extremely poor or absent visual imagination (Faw, 2009).
Aside from Faw’s limited work, this phenomenon has not received much scientific
exploitation. Recently, however, Professor Adam Zeman at the University of Exeter has begun
conducting research on this topic. This condition now named ‘aphantasia’ (Zeman, 2015), is
hypothesized to be the result of either of two different types of neurogenic visual imagery
impairments: i) visual memory disorders, or ii) ‘imagery generation’ deprivation (Farah, 1984).
To explore further features of aphantasia, Zeman and his team distributed a shortened version of
the VVIQ as well as a supplemental questionnaire addressing additional personal information to
21 participants who suspected that they had the condition, 19 of whom were male. This testing
generated various results; 5/21 reported having relatives who experience similar symptoms, and
most participants claimed having realized their visualizing deficit during their teens or early
twenties through conversation with ‘normal’ visualizers. Interestingly, despite the 21
participants’ VVIQ scores being tremendously lower than those of the 121 control patients, many
subjects claimed to experience involuntary imagery at various times. This first exploratory study
of aphantasia began to define and quantify the condition, and acted as a good basis for further
research (Zeman, 2015).
I created a questionnaire and distributed it via the internet to self-proclaimed aphantasia
patients to gather additional statistics of the condition. This study gathered demographics of the
tested population, as well as information regarding the effects of aphantasia on learning ability,

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glancing ability, facial recognition ability, creativity, career and memory. This data will facilitate
an improved understanding of aphantasia within the scientific community, and act as a base for
further studies aimed at determining the cause of the condition.
Goal of Study/Hypothesis
Develop a survey to be administered to self-proclaimed aphantasiacs to verify their condition, as
well as gage additional information about aphantasia that will facilitate further scientific
investigations. This will serve as the first in depth epidemiological study of this condition,
providing useful information about the demographics of the population of non-visualizers, as
well as highlighting the effects of the condition on various functions. When compared to a
control group of normal visualizers, it is expected that aphantasiacs will report distinctively
different functional experiences that can thereafter be considered characteristics of the condition.
Methodology
Professor Adam Zeman’s original survey and questionnaire (Zeman, 2015) were used as
reference material while creating this survey with original questions. After obtaining IRB
approval (based on the premise that my survey includes IP tracked to avoid duplication, de-
identification/confidentiality, no participants < 18 and no harm generated, deeming my survey
ethically just), the survey was distributed by means of social media on:
• Facebook groups for aphantasia patients
o “Aphantasia (Non-Imager / Mental Blindness) Awareness Group”
o “Aphantasia - Non-Imager/Mental Blindness Awareness”
• Aphantasia forum
o http://aphant.asia/
• Twitter
The following message was posted in conjunction with the survey:
“Hello, my name is Melody Munitz and I am a student conducting aphantasia research in
association with the team of Dr. Adam Zeman at the University of Exeter. I am
conducting experiments in an effort to gather further statistics about this recently
surfacing condition, and have created a survey with more in depth and wide-range
questions to learn more about this condition. My hope is that the results from this survey
will provide information that will aid in further classification of this condition that will

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facilitate scientific advances in the field of aphantasia. Anyone who claims to have a
severely weakened or nonexistent mind’s eye who would be willing to take part in this
scientific study should click on the link below to be directed to the questionnaire. Please
note: All survey responses are de-identified. You must be 18 years or older to participate
in this study.
https://aphantasiasurvey.typeform.com/to/bYMubp”
Following the collection of the data, statistics were performed. The mean, standard deviation,
and standard error were calculated for each question for which it was appropriate. For
comparison questions utilizing a Likert scale (such as a 1-5 scale to gauge strength or quality)
unpaired t-tests were performed. For “yes or no” questions, the data was regarded as binomial
("yes" and "no" responses translated to ‘0’ and ‘1’) and a z-test was performed. This was an
appropriate statistical test to use because the large "n" value of this data set made it so that a t-
test and z-test would yield near equivalent statistical data.
Role of the Student: I designed my own survey, utilizing Dr. Zeman’s questionnaire (Zeman,
2015) as reference material. I identified an aphantasia group on Facebook to which the survey
was posted. I performed the statistical calculations and wrote my paper independently of my
mentor.
Role of the Mentor: There was brief discussion of the results with the mentor.
Results
Population Demographics:
There was a fairly even spread of ages tested, ranging from 18-75, with the 25-34 range being
the most popular. There was a relatively even split between male and female subjects (53%
female: 47% male). Subjects were from the United States and other countries (42% US: 58%
Other). Of aphantasiacs, 42% reported having been in the academic top 10% in high school,
comparable to the 39% of the control group that reported such, showing that aphantasiacs don’t
feel that aphantasia has hindered their academic success. Most subjects expressed that their
visual imagery had been equally weak throughout their life, and did not seem to be the result of
an accident or other change.

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Confirming Aphantasia:
Since most aphantasiacs were self-identified (only 4% reported that their mind’s eye weakness
has been verified by a healthcare professional), it was important to verify their standing as
aphantasiacs. The first questions of the survey asked subjects to undergo a series of
visualizations and record their experience. The experimental group consistently reported low
numerical responses, showing their diminished mind’s eye and categorizing them as
aphantasiacs. The consistently high numerical responses of the control group on the same
questions verified them as non-aphantasiacs, making them a viable control population.
Figure 1
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
1a 1b 1c 1d
Mean!Strength!of!Image
Shop!Visualization!
Aphantasiacs Control
●● ●●●● ●●
FIG. 1.
Question 1: Think of the front of a shop which you often go to. Try to form a visual image, and
rate the vividness of it is using the five-point scale described below.
1a: “The overall appearance of the shop from the opposite side of the road.”
1b: “A window display including colors, shapes and details of individual items for sale.”
1c: “You are near the entrance. The color, shape and details of the door.”
1d: “You enter the shop and go to the counter. You hand the clerk your money, and they give you
back change.”
5 - Perfectly clear and vivid as real seeing; 4 - Clear and reasonably vivid; 3 - Moderately clear
and lively; 2 - Vague and dim; 1 - No image at all, you only “know” that you are thinking of the
object
The mean is graphed. Error bars are +/- 1 standard error of the mean. n=394 for experimental
group and n=150 for control group. ●●, p<0.001.

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Figure 2
0
1
2
3
4
5
6
Aphantasiacs Control
Mean!Strength!of!Image
Red!Triangle! Visualization
●●
FIG. 2.
The mean is graphed. Error bars are +/- 1standard error of the mean. n=394 for experimental
group and n=150 for control group. ●●, p<0.001.

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Life Function of Aphantasiacs:
The collected data suggests that aphantasiac’s diminished visualization abilities affect various
aspects of their functionality, specifically their career, creativity, memory, learning ability,
glancing ability, and facial recognition abilities. Normal visualizers reported that their visual
imagery capabilities had a very strong impact on these aspects of their life, showing that visual
imagery is a skill that the normal population relies on heavily for daily function. Thus, it would
be expected that those who do not possess the ability to visualize would experience a noticeable
deficit, and would note very high impact of their lack of visualization abilities in Figure 3.
However, aphantasiacs reported mid-range impact, suggesting that aphantasiacs do not find their
condition debilitating, but rather, something they are finding ways to compensate for.
Figure 3
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
Career Creativity! Memory! Learning!Ability Glancing!Ability Facial!Recall!!
Mean!Strength!of!Impact!of!Visualization!Abilities
Impact!of!Visualization!Abilities!On!Various!Skills
Aphantasiacs Control
●●
●● ●●
●●
●●
●●
FIG. 3.
“1 = no impact; 5 = strong impact”
The mean is graphed. Error bars are +/- 1standard error of the mean. n=388 for experimental
group and n=128 for control group. ●●, p<0.001.
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Considering the reported impact of visualization on creativity, it would be expected that
aphantasiacs would experience decreased creativity. However, most aphantasiacs reported
above-average creativity, just as the control group did. Here, it is beneficial to consider the
varying definition of ‘creativity’; these results may either speak to artistic creativity, or to being a
creative thinker (i.e. thinking in a creative manner). The latter may be more prominent among
aphantasiacs, as their possible compensation for their lack of visual imagery may mean they rely
on other, ‘creative’, methods of thinking.
Figure 4
23.4 25.4
37.2
14
2.7 3
44
21.3
0
5
10
15
20
25
30
35
40
45
50
minimal average above!average excellent
Percent!of!Sample
Level!of!Creativity
Aphantasiacs Control
FIG. 4.
Percentages of the sample are graphed. n=393 for experimental group and n=150 for control
group.

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For memory, there was a spread of strengths reported by aphantasiacs, but very few reported
“excellent” memory. Most of the control group reported above-average memory, with very few
reporting memory weaker than average. The memory strength reported by aphantasiacs is
swayed to the lower end of the scale, whereas the results from the control group are swayed to
the higher end, showing that aphantasia does have an impact on memory, but not a drastic one.
Since memory tends to be highly dependent on mental images, and aphantasiacs are not
reporting an extremely weak memory, they must be finding means of compensation and relying
on other methods to remember and memorize.
Figure 5
21 23.3 26.7
21.5
7.4
0
6
32.9
53.7
7.4
0
10
20
30
40
50
60
very!poor below!average average above!average excellent
Percent!of!Sample
Strength!of!Memory
Aphantasiacs Control
FIG. 5.
Percentages of the sample are graphed. n=390 for experimental group and n=149 for control
group.

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Since visualization tends to play a large role in learning, it was relevant to assess how
aphantasiacs learn. While most control subjects reported being visual learners, this was not the
case among aphantasiacs. Rather, most aphantasiac subjects reported being either “kinesthetic”
or “read-write” learners, with the smallest percentage reporting being visual learners. This
suggests that aphantasiacs are learning differently than the rest of the population, and though
they are just as likely to be intelligent and high-achieving, are relying on work-arounds to learn
and memorize.
Figure 6
23.4
12.2
30.8 29.8
6.9
8.7
2.7
26 26.7
36
0
5
10
15
20
25
30
35
40
I'm!not!sure! auditory kinesthetic!or!
'hands!on'
read-write visual
Percent!of!Sample
Learning!Style
Aphantasiacs Control
FIG. 6.
Percentages of the sample are graphed. n=393 for experimental group and n=150 for control
group.

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Since glancing ability, the ability to take in information at a glance, relies on taking a mental
snapshot for later recall and analysis, it would be expected that aphantasiacs would have weak
glancing abilities. Indeed, most aphantasiacs reported either average, very poor, or mildly below
average glancing abilities, with very few reporting above average or excellent. These results are
significant when compared to the control group’s responses of primarily average or above
average, with the smallest percentages reporting mildly below average or very poor. The
aphantasiac responses skewed to the lower end of the spectrum, compared to the non-skewed
control group responses, suggest that aphantasiacs do in fact struggle with glancing ability.
Figure 7
27 25.5
30.1
12.2
5.1
2.7 4.7
44 41.3
7.3
0
5
10
15
20
25
30
35
40
45
50
very!poor mildly!below!
average
average above!average excellent
Percent!of!Sample
Strength!of!Glancing!Ability
Aphantasiacs Control
FIG. 7.
Percentages of the sample are graphed. n=392 for experimental group and n=150 for control
group.

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Facial recall requires one to capture a mental image of a face, and thus it seemed likely that
aphantasiacs would have difficulty recalling faces. Nearly 60% of aphantasiacs reported
difficulty with this—a significantly higher percentage compared to the approximately 15% of
normal visualizers that reported difficulty recalling faces.
Figure 8
57.9
14.7
0
10
20
30
40
50
60
70
Aphantasiacs Control
Percent!of!Sample
Percent!Who!Report!Difficulty!Recalling!Faces
●●
FIG. 8.
Percentages of the sample are graphed. Error bars show standard error. n=392 for
experimental group and n=150 for control group. ●●, p<0.001 as determined by a z-test.

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Function of Other Sensory Imagery:
While aphantasia is defined by diminished visual imagery, it was a point of interest to see if
other sensory imagery is also affected by the condition. Subjects were asked to rate the strength
of their imagery when attempting to imagine, for example, a song, the feeling of a certain fabric,
the taste of their favorite food, and the scent of a candle. Compared to the control subjects, the
aphantasiacs reported consistently lower strength of imagery for sounds, textures, tastes, and
smells, suggesting that Aphantasia is inhibiting not only visual imagery, but also auditory,
tactile, gustatory, and olfactory imagery.
Figure 9
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
Sounds! Textures! Taste Smell
Mean!Strength!of!Sense!Imagery
Strength!of!Other!Sensory!Imagery
Aphantasiacs Control
●● ●●
●●
●●
FIG. 9.
The mean is graphed. Error bars are +/- 1 standard error of the mean. n=388 for experimental
group and n=127 for control group. ●●, p<0.001.

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Function of Dreaming:
Since visual dreaming requires the playback of visual images in the mind’s eye, it was under
question if aphantasiacs would be able to dream visually. Surprisingly, many of them can.
Because of the large number of participants in the study, the 81.1% of aphantasiacs who dream
visually is statistically significant when compared to the 94.6% percent of normal visualizers
who dream visually. However, we must look beyond the statistics to understand what this
particular data set is truly saying. In actuality, this 81.1% is much higher than expected, as based
on their deficit in visualization, it seemed highly unlikely that aphantasiacs would dream visually
at all.
Figure 10
81.1
94.6
0
20
40
60
80
100
120
Aphantasiacs Control
Percent!of!Sample
Percent!of!Subjects!Who!Dream!Visually
●●
FIG. 10.
Percentages of the sample are graphed. Error bars show standard error. n=387 for
experimental group and n=149 for control group. ●●, p<0.001 as determined by a z-test.

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Though aphantasiacs are dreaming visually, they seem to be doing so less frequently than the
population of normal visualizers. Whereas over half of the control population reports always
having visual dreams, and only a small percentage report that their visual dreams occur rarely,
the aphantasiacs responses were spread across the options, showing that their visual dreams are
less consistent than those of the normal-visualizer population.
Figure 11
38.7
25.9
35.5
53.9
37.6
8.5
0
10
20
30
40
50
60
always!when!dreaming! frequently!when!dreaming! rarely!when!dreaming!
Percent!of!Sample
Frequency!of!Visual!Dreams!
Aphantasiacs Control
FIG. 11.
Percentages of the sample are graphed. n=313 for experimental group and n=141 for control
group. These populations are smaller because only those who reported “yes” to having visual
dreams in the previous question were presented this question.

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As in Figure 10, the statistical significance displayed in the data regarding the strength of these
dreams can be misleading due to the large population. While the strength of the dreams
experienced by aphantasiacs is lower than the strength of dreams experienced by the control
group, the aphantasiac strength reported is still surprisingly high. Especially when compared to
the mean strength of wakeful visualization reported by aphantasiacs as approximately 1.5 (see
Figures 1 and 2), the mean strength of visualization while dreaming reported here as
approximately 3.4 is significantly higher, and should be legitimately considered.
Figure 12
Discussion
This questionnaire yielded many unprecedented results that begin to characterize and
explain aphantasia. While this condition does not seem to act as a major deficit to the success of
those who have it, it certainly affects the way they function and learn (see Figure 3). Their
relatively high strengths of creativity and memory suggest that they must be implementing
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
Aphantasiacs Control
Mean!Strength!of!Visual!Dream!
Strength!of!Visual!Dreams!
●●
FIG. 12.
“1 = vague, lifeless; 5 = extremely vivid”
The mean is graphed. Error bars are +/- 1 standard error of the mean. n=388 for experimental
group and n=127 for control group. ●●, p<0.001.

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mental and lifestyle adjustments to compensate for the effects of their diminished visualization
abilities (see Figures 4 and 5). However, there do seem to be some functions that aphantasiacs
cannot compensate for so readily; they did report significantly weak glancing ability as well as
difficulty recalling faces (see Figures 7 and 8). This split between what they can and can’t
compensate for seems to fall logically, as glancing ability and facial recall are based almost
entirely off of the formation and recall of a mental image, whereas creativity and memory are
supported by other mechanisms. One of the most fascinating results of this study was that the
vast majority of people with decreased visual imagery also have weakened imagery of their other
senses (see Figure 9). This leads one to believe that the neural deficit that causes aphantasia is
not necessarily based specifically in brain processes relating to visualization or sight, but rather
in a more general process relating to the recall of all modalities of sensory imagery. Another
surprising and interesting result was that most aphantasiacs (81%) experience visual dreams, and
peculiarly, very vivid ones. This result calls for further research to explain what brain mechanism
allows for involuntary visualization while asleep, but not voluntary visualization while awake. In
providing new and interesting results, this survey adhered to the goals of study and served as the
first in depth epidemiological study of aphantasia. Though this survey should not be considered
sole proof for the drawn conclusions, it has helped to highlight what areas of aphantasia should
receive further research.
Conclusion
Research of aphantasia is important as it appears to be a condition that is affecting a
significant number of people, supported by Faw’s proposal that 2.1-2.7% of a population are
likely to have extremely diminished or entirely nonexistent visual imagery capabilities (Faw,
2009), and recognizing the high number of responses this study received in a short period of
time. Overall, this study suggested that aphantasiacs are finding ways to compensate for their
visual imagery deficit, as they are high functioning and can even dream visually. The next step in
aphantasia research is underway with the recent completion of an fMRI study observing the brain
function of poor visualizers. That study found that those with low visual imagery capabilities
utilize a more widespread set of brain regions when attempting to visualize than those with
average or above average visualization skills (Fulford et al 2017). This result supports the
hypothesis suggested by my study that aphantasiacs are utilizing compensatory brain processes

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different than normal visualizers. Further neuroimaging studies should be conducted to help us
understand why aphantasia seems to affect imagery of all the senses, as well as how aphantasiacs
are able to dream visually. If a large percentage of aphantasiacs are dreaming in images, often
vivid ones, they must be able to create and store visual images that are retrievable during
dreaming, but not consciously during wakefulness. Additional brain imaging studies may help to
pinpoint the neural pathways that are prohibiting conscious visual imagery recall, helping us to
understand how visual imagery is generated in the brain. Such findings can relate to other fields
by possibly aiding in the development of therapies for patients with visual recall impairments,
(caused by stroke or brain injuries) or by expanding the knowledge base of other conditions
pertaining to visual imagery such as synesthesia (a crossing of sensory modalities) or
schizophrenia (where there may be visual hallucinations). In learning about how visualization
occurs, we can expand our understanding of the functions and processes carried out by different
structures of the human brain.
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Faw, B. (2009). Conflicting intuitions may be based on differing abilities - evidence from mental
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Fulford, J., et al., The neural correlates of visual imagery vividness e An fMRI study and
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Galton, Francis (1880). Statistics of mental imagery. Mind, 5, 301-318.
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