Oliver Sacks: Mishearings

Every mishearing is a novel concoction. The hundredth mishearing is as fresh and as surprising as the first. I am often strangely slow to realize that I have misheard, and I may entertain the most far-fetched ideas to explain my mishearings, when it would seem that I should spot them straight away. If a mishearing seems plausible, one may not think that one has misheard; it is only if the mishearing is sufficiently implausible, or entirely out of context, that one thinks, “This can’t be right,” and (perhaps with some embarrassment) asks the speaker to repeat himself, as I often do, or even to spell out the misheard words or phrases.
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While mishearings may seem to be of little special interest, they can cast an unexpected light on the nature of perception — the perception of speech, in particular. What is extraordinary, first, is that they present themselves as clearly articulated words or phrases, not as jumbles of sound. One mishears rather than just fails to hear.

Mishearings are not hallucinations, but like hallucinations they utilize the usual pathways of perception and pose as reality — it does not occur to one to question them. But since all of our perceptions must be constructed by the brain, from often meager and ambiguous sensory data, the possibility of error or deception is always present. Indeed, it is a marvel that our perceptions are so often correct, given the rapidity, the near instantaneity, with which they are constructed.

One’s surroundings, one’s wishes and expectations, conscious and unconscious, can certainly be co-determinants in mishearing, but the real mischief lies at lower levels, in those parts of the brain involved in phonological analysis and decoding. Doing what they can with distorted or deficient signals from our ears, these parts of the brain manage to construct real words or phrases, even if they are absurd.

While I often mishear words, I seldom mishear music: notes, melodies, harmonies, phrasings remain as clear and rich as they have been all my life (though I often mishear lyrics). There is clearly something about the way the brain processes music that makes it robust, even in the face of imperfect hearing; and, conversely, something about the nature of spoken language that makes it much more vulnerable to deficiencies or distortions.

Playing or even hearing music (at least traditional scored music) involves not just the analysis of tone and rhythm — it also engages one’s procedural memory and emotional centers in the brain; musical pieces are held in memory and allow anticipation.

But speech must be decoded by other systems in the brain as well, including systems for semantic memory and syntax. Speech is open, inventive, improvised; it is rich in ambiguity and meaning. There is a huge freedom in this, making spoken language almost infinitely flexible and adaptable — but also vulnerable to mishearing.
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And yet there is often a sort of style or wit — a “dash ”— in these instantaneous inventions; they reflect, to some extent, one’s own interests and experiences, and I rather enjoy them. Only in the realm of mishearing — at least, my mishearings — can a biography of cancer become a biography of Cantor (one of my favorite mathematicians), tarot cards turn into pteropods, a grocery bag into a poetry bag, all-or-noneness into oral numbness, a porch into a Porsche, and a mere mention of Christmas Eve a command to “Kiss my feet!”

A professor of neurology at the New York University School of Medicine, and the author, most recently, of the memoir “On the Move.”
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