It is to be expected that human beings differ in how they process sensory information, since their brains, like other physiology, can differ. Some differences, if they seem disabling, may be labelled pathology or disorder. On the other hand, simply labelling doesn’t render a condition disabling. That is a distinction sometimes overlooked by researchers in clinical psychology.

The tendency to talk about phenomenal experience in medicalized terminology reflects long-standing confusions collectively known as the Mind-Body Problem. It shifts the perspective from a first-person to a third-person point of view. It also reflects the common habit of reification, in which an experience is objectified as a thing. (The rationale is that experiences are private and thus inaccessible to others, whereas objects or conditions are public and accessible to all, including medical practitioners.) Thus dis-ease, which is a subjective experience, is reified as disease, which is a condition—and often a pathogen—that can be dealt with objectively and even clinically. To thus reify a personal experience as an objective condition qualifies it for medical treatment. Containing it within a medical definition also insulates the collective from something conceived as strange and abnormal. On the one hand, it can become a stigma. On the other, people may take comfort in knowing that others share their experience or condition, mitigating the stigma.

Admittedly, psychology and brain science have advanced largely through the study of pathology. Normal functioning is understood through examining abnormalities. However, the unfortunate downside is that even something such as synesthesia, which is perfectly orderly and hardly a disability, can nevertheless be labelled as a disorder simply because it is unusual. Even something not unusual, such as pareidolia (seeing images or hearing sounds in random stimuli), has a clinical ring about. Moreover, categorization often suggests an either/or dichotomy rather than a continuous spectrum of possibilities. You either “have” the condition or you don’t, with nothing in between. There is also a penchant in modern society for neologisms. Re-naming things creates a misleading sense of discovery and progress, perhaps motivated ultimately by a thirst for novelty and entertainment conducive to fads.

A recent social phenomenon that illustrates all these features is the re-discovery of “aphantasia.” This is a term coined by Adam Zeman et al in a seminal article in 2015, but first documented in the late 19th century. It means the absence (or inability to voluntarily create) mental imagery. Its opposite is “hyperphantasia,” which is the experience of extremely vivid mental imagery. The original paper was a case study of a person who reported losing the ability to vividly visualize as the incidental result of a medical procedure. As it should, this stimulated interest in the range of normal people’s ability to visualize, as subjectively reported. But there is a clear difference between someone comparing an experience they once had to its later loss and a third party comparing the claims of diverse people about their individual experiences. The patient whose experience changed over time can compare their present experience with their memory. But no one can experience someone else’s visualizations (or, for that matter, the auditory equivalents). Scientists conducting surveys can only compare verbal replies on questionnaires, whose questions can be loaded, leading, and interpreted differently from individual to individual.

The study of mental imagery and “the mind’s eye” is a laudable phenomenological investigation, adding to human knowledge. But the term aphantasia is unfortunate because it suggests a specific extreme condition rather than the spectrum of cognitive strategies for recall that people employ. The associations in the literature are clinical, referring to “imagery impairment,” “co-morbidities,” etc. Surveys implicitly invite you to compare your degree of visualization with the reports of others, whereas the only direct comparison could be to your own experience over time. (I can say in my own case that my ability to voluntarily visualize seems to have declined with age, though memory in general also seems unreliable, which may be part of the same package.) Apart from aging, if there is a decline in cognitive abilities, then there is some justification to think of a disability or disorder. Overall, however, the differences between visualizers and non-visualizers seems to be mostly a variation in degree and in the style of retrieving and manipulating information from memory, with some advantages and disadvantages of each style with respect to various tests.

Moreover, “visual imagery” is an ambiguous notion and term. There can be all sorts of visual images both with eyes open and eyes closed: after images, dreams, hallucinations, eidetic images, “mental” images, imagination, apparitions and spiritual visions, etc. They can be the result of voluntary effort or spontaneous intrusions. All these could be rated differently on questionnaires as to their vividness. The widely used Vividness of Visual Imagery Questionnaire asks you to “try to form a visual image” in various situations and rate your experience on a scale of 1 to 5, with 5 being “perfectly realistic and vivid as real seeing.” If that were literally so, what would be the basis on which to distinguish it from “real” seeing? Some people may indeed have such experiences, which are usually labelled schizophrenic or delusional.

But such is language that we subtly metaphorize without even realizing it. Whether they visualize relatively vividly or relatively poorly, people who are otherwise normal are not comparing their real-time experience to an objective standard but to their own ordinary sensory vision or to what they imagine is the experience of others. They are rating it on a scale they have formed in their own mind’s eye, which will vary from person to person. No one can compare their experience directly with that of better or worse visualizers, but only with their interpretation of others’ claims or with their own normal seeing and their other visual experiences such as dreaming.

In descending order, the other four choices on the questionnaire are: (4) clear and lively; (3) moderately clear and lively; (2) dim and vague, flat; and (1) no image at all—you only “know” that you are thinking of the object. In my own case, I can voluntarily summon mental imagery that I can hardly distinguish from merely “thinking” of the object. Yet, these images seem decidedly visual, so I would probably choose category (2) for them.

But categorizing an experience is not the same as categorizing oneself or another person. I’ve had vivid involuntary eidetic images that astonish me, such as continuing to “see” blackberries after hours spent picking them. That might be category (3) or (4). Yet even these I cannot say are in technicolor. While I can picture an orange poppy in my mind’s eye, I cannot say that I am seeing the scene in vivid color or detail. (Should I call the color so visualized “pseudo-orange”?) As in all surveys, the burden is on the participant to place their experience in categories defined by others. No one should feel obliged to categorize themselves as ‘aphantasic’ as a result of taking this test. Perhaps for this reason, among the many websites dedicated to studies of visualization, there are even some that tout aphantasia as a cognitive enhancement rather than a disability.

In our digital age we are used to dichotomies and artificial categories. How many colors are there in the rainbow? Six, right? (Red, orange, yellow, green, blue, and violet.) But, in classical physics there are an infinite number of possible wavelengths in the visible part of the spectrum alone, which is a continuum. (Quantum physics might propose a finite but extremely large number.) No doubt there are differences in people’s abilities to discriminate wavelengths, and in how they name their color perceptions. A few people are unable to see color at all, only shades of intensity—a condition called achromatopsia. Yet, that is hardly what society misleadingly calls ‘color-blindness’, which is rather the inability to distinguish between specific colors, such as blue and green, which are close to each other in the spectrum. Similarly, perhaps with further research, aphantasia will turn out to mean something more selective than the name suggests.

Perhaps the general lesson is to be careful with language and categorization. Statements are propositions conventionally assumed to be either true or false. That is always misleading and invites dispute more than understanding. If you fall into that trap, perhaps you are an eristic or suffering from philodoxia. (Surely there is a test you can take to rate yourself on a scale of one to five!) One thing is quite certain. Naming things is a psychological strategy to deal with the acatalepsy common to us all. Or perhaps, in bothering to write about this, I am simply quiddling.

[Thanks to Susie Dent’s An Emotional Dictionary for the big words.]