A blindsighter is someone who can’t see in part of their visual field, but when given choices, can accurately guess what’s there. These individuals have damage to their primary visual cortex, but fully functional eyes. Their residual ability to (seemingly) “see unconsciously” derives from parts of the optic nerve which bypass the damaged brain region.
A “super blindsighter” is a hypothetical blindsighter, imagined by Ned Block, who learns to prompt themselves to guess at what’s in their blindfield, thereby gaining some ability to spontaneously “see” things without consciously seeing them, i.e. without having visual experience of them.
Something like blindsight is known to occur in audition, a kind of “deaf hearing“. I’m fairly confident I’m something of an “anosmic-smeller”, perhaps even a super anosmic-smeller. (Anosmia is the loss of smell, akin to blindness or deafness.)
I lived most of my life, including all of childhood, with an enlarged septum and nasal turbinates, plus poor sinus drainage which lead to near constant nasal blockage. As I kid I knew my sense of smell was very poor, and I (now) assume it was always because air simply did not move freely through my nose, or at least did not reach my olfactory receptors. Although I had corrective surgery to open up my nasal passages a few years ago, I suspect that twenty-plus years of disuse has lead to extensive degeneration of my olfactory nerves and olfactory processing in my brain.
While I’ve always had some sense of smell, it seems different than most people’s. Most conspicuously, I rarely smell things. Encountering a smell — finding myself with an olfactory experience — is always a notable event for me. I don’t go about my day enjoying a smellscape. Instead, every now and then I’m hit in the face with an odour that intrudes into consciousness, a consciousness that’s normally devoid of any odours at all. This happens now, after corrective surgery, maybe half a dozen times a week. Before surgery, it happened maybe a few times a year.
For example, I often cook with kimchi. I’m told it has a pungent, overpowering odour. If I stick my nose in a kimchi container, I might smell something once out of a hundred times, although that one time will be a quite vivid experience of a rich, textured odour. For another example, my partner and I also often cook fatty burgers with malt vinegar. The combination of the two frying in a pan creates a delicious smell, but one I’ve smelled maybe only two or three times over the past six months (despite making the meal several times a week).
None of this amounts to anything like anosmic-smelling. What’s more interesting, though, are a broad class of experiences I find hard to categorize. In the past I might have called them “muted”, or “muted smelling”. For example, I remember as a child sometimes riding in the car past a dead skunk on the road. My parents would always comment on the horrible smell. I usually did not notice it. I did not know what they were talking about. Years later, I did come to learn (sort of) what skunk smells like. Looking back, I can recognize that I was having some sort of experience of the skunk smell, but I did not recognize it as an olfactory experience, i.e. as a smell.
This is similar to what blindsighters often say about their own vision. They note that stimuli in their blindfield often induce experiences, but experiences they wouldn’t call visual. They don’t recognize it as seeing. They often describe it as seeing through a veil, or use other analogies. I think those fit with this broad class of olfaction-induced experiences I have. For example, if I stand near a recent skunk spray, or by the compost bin of my apartment (both very strong odours, so I’m told), I do have an experience, but it’s at best like the experience I’d have if I tried to imagine an odour. For example, if I imagine what it’s like to smell kimchi (a vivid olfactory experience I do sometimes have), I induce a very “muted” version of the actual experience. I can almost, sort of, smell kimchi, in my “mind’s nose”.
This is what it’s normally like for me to actually smell strong odours, like skunk or rotting compost. I can almost, sort of smell them. But, like blindsighters, I’d want to strongly protest that I’m actually smelling something, or having a real olfactory experience. In fact, it’s literally taken me years (and years!) of careful introspection and training to recognize these muted experiences. I’ve had to learn, through much practice, to suss them out and reliably identify them as something caused by my nose. Recall how, when I was a young child, I regularly had experiences (e.g., of roadkilled skunks) induced by olfactory stimulation, but did not recognize them as such. I suspect that these experiences are induced, in part, by retronasal olfaction (air moving over olfactory receptors from inside the mouth, as happens in taste), not orthonasal olfaction (air moving from outside the nose). These two modes of olfaction induce quite different experiences, so perhaps that’s part of it.
Maybe these muted olfactory experiences don’t quite make me anosmic. (Most people still agree that the “muted” visual experiences of blindsighters still count as blindness.) But again, the term “muted” is misleading. It’s really not as if I’m having an otherwise normal olfactory experience, albeit one that’s muted, i.e. as if I’m smelling a subtle odour. It takes remarkable effort to notice and track these experiences, so much effort that I’m often unsure if I’m having them at all. There is, often, some element to self-prompted forced-choice guessing. I’m hit with the thought that I might be smelling something. I ask myself, “Am I smelling something?” If I decide (guess) “yes”, I next start asking myself what I might be smelling. I look around — do I see a plausible odour source? If so, I start self-prompting again: Am I smelling that (the cooking food, the trash can, etc.)?
At this point, all this seems a lot like what you’d want to call super anosmic-smelling. I do a lot of spontaneous, self-prompted forced-choice guessing to suss out my own olfactory experiences — to determine what I’m smelling. So, while I do sometimes have normal olfactory experiences, these are not my normal mode of smelling. Smelling, in the way that other people seem to describe their own sense of smell, is a rare occasion for me. It always comes as a surprise. It’s vivid and intrusive and different from the norm. The norm is something that seems much more like anosmic-smelling, or even super anosmic-smelling.