Hallucinations полностью

Others may be haunted by a single constant smell of such complexity that it seems to conglomerate almost all the bad smells in the world. Bonnie Blodgett, in her book Remembering Smell, describes the phantosmic world she was plunged into following a sinus infection and the use of a potent nasal spray. She was driving along a state highway when she first detected a “weird” smell. She checked her shoes at a gas station, found them clean, then wondered if there was something amiss with the heater fan in the car — a dead bird perhaps? The smell pursued her, waxing and waning in intensity but never absent. She explored a dozen possible external causes and was finally, reluctantly, forced to the realization that the smell was in her head — in a neurological, not a psychiatric, sense. She described the smell as resembling “shit, puke, burning flesh and rotten eggs. Not to mention smoke, chemicals, urine and mold. My brain had truly outdone itself.” (Hallucination of particularly vile smells is called cacosmia.)

While humans can detect and identify perhaps ten thousand distinct smells, the number of possible smells is far greater, for there are more than five hundred different odorant receptor sites in the nasal mucosa, and stimulation of these (or their cerebral representations) may be combined in trillions of ways. Some hallucinated smells may be impossible to describe because they are different from anything ever experienced in the real world, and evoke no memories or associations. New, unprecedented experiences can be a hallmark of hallucinations, for when the brain is released from the constraints of reality, it can generate any sound, image, or smell in its repertoire, sometimes in complex and “impossible” combinations.

1. Molly Birnbaum, an aspiring chef who became anosmic after being struck by a car, has described the anosmic’s predicament eloquently in her memoir Season to Taste.

2. Among these other conditions is infection with the herpes simplex virus, which can attack nerves (including sometimes the olfactory nerves), both impairing and stimulating them. The virus can remain dormant for long periods, sequestered in nerve ganglia, and suddenly reemerge at intervals of months or years. One man, a microbiologist, wrote to me: “In the summer of 2006, I began to ‘smell things,’ a faint pervasive odor that I could not identify (my best guess was … wet cardboard).” Prior to this, he said, “I had a highly sensitive nose, and was able to identify my laboratory cultures by smell alone, or subtle differences in organic solvents, or faint perfumes.”

He soon developed a constant hallucination of the smell of rotting fish, which faded only after a year had passed, along with most of his “olfactory acuity and the subtlety of most foods.” He wrote:

Certain odors are completely gone — feces(!), baking bread, or cookies, roasting turkey, garbage, roses, the fresh soil smell of Streptomyces … all gone. I miss the smells of Thanksgiving, but not the smell of public toilets.

The dysosmia and phantosmia were due to a reemergence of the herpes simplex 2 which he had contracted many years before, and he is intrigued that these are always preceded by hallucinatory smells. He writes, “I smell the onset of herpes reactivation. A day or two prior to the onset of a neuritis episode, I again have olfactory hallucinations of the last strong smell I noticed. [This smell] persists during the neuritis and fades as the neuritis fades.… The strength of the hallucinations is correlated with the severity of the generalized neuritis.”