When most people hear the word hallucination, they usually think of the auditory or visual kind. However, smell-related hallucinations exist too. There are two terms for them: phantosmia means smelling an odor when none is present, while parosmia is when a real odor is perceived differently than it normally would be.
Both are actually quite common, and can be triggered by infectious diseases (including COVID). The sense of smell in humans is already relatively weak compared to the other senses (this is often not the case in other mammals, such as dogs). This might make the human sense of smell more susceptible to neurologically-based alterations, similar to how people with weaker-than-normal vision sometimes are more prone to visual hallucinations.
In religious contexts, certain odors are commonly associated either with holiness or unholiness, and many forms of religious devotion incorporate smells such as incense. Unlike Jaynes’ auditory hallucinations, religious experiences involving smell never really went away, though there are differences (smells play a far bigger role in Catholicism than in most varieties of Protestantism, for instance).
A remarkable example from just a year or so ago is the cult of Tawee Nanla in Thailand, whose followers believed their leader was a holy man with healing powers, and so they regularly consumed his feces, dead skin, and urine. They also reportedly collected bodily fluids that drained out of coffins and then bathed in them. They voluntarily did all these things rather than being commanded to by their leader; this didn’t stop Thai police from raiding the group’s compound and arresting the cultists.
Similar practices have sporadically occurred in India as well (the Aghoris are known for consuming parts of dead human bodies).
It seems likely that some form of parosmia could be involved here, as most people would be far too grossed out to eat feces or corpses, both of which have intensely repulsive odors. I read one article about Tawee Nanla’s cult, which mentioned that one of his followers claimed that his feces actually smelled pleasant, at least to people with truly enlightened minds (meaning the cultists). If ordinary people found the smell disgusting it’s just because they had impure thoughts. I wonder if something like Jaynes’ theory might apply to smell as well as hearing.
Olfactory hallucinations
Re: Olfactory hallucinations
Quite interesting. In my book on ancient Egypt, I point out how apparently people could "smell" the gods; presumably this was a type of hallucination. I think I mentioned to this group that twice, out of the blue, I hallucinated the smell of saguaro cacti (I lived in the southwest for 10 years). Funny how the mind works.
