PROLOGUE --
I’m not a neurolinguist, but as the
expression goes, “some of my best friends
are.” They like to remind us that
the human brain is an organizer. As
marvelous as the brain is, it cannot manage random, disassociated data;
therefore, our brains are crafted to sort, classify, categorize, and relate. “STORIES”
exist in all human cultures because human brains use this format to organize
the events of our existence, and give structure and meaning to our lives. For each of us, our lives become stories
linking and defining who and why we are.
With no particular organizational structure, I share a collection of my
stories:
SOUNDS OF MY LIFE
I’ve spent many hours of my life
listening to, analyzing, crying, sweating, and laughing over some of the
strangest sounds made by child, man, or beast.
In 1973-4, I spent over 300 hours (I know because they were clocked on a
room-sized IBM computer), studying the stuttered and fluent utterances of five
speakers. One of my professors, Oliver
Bloodstein, said I put the moment of stuttering under a microscope and
dissected it. In the 80’s I did similar
work on the lesser known voice disorder, spasmodic dysphonia, eventually
demonstrating the neurological basis of the problem, and paving the way for new
treatments.
However, along the road, I spent a
few hours on some more quixotic sounds.
Some of these came my way through colleagues and others from student
projects. Among my favorite non-human
sounds are: talking birds, crab whistles, dolphins, and talking dogs. Several grad students over my years of
teaching acoustic phonetics have repeated the experiments of Kenneth Stephens,
using a variety of talking pet birds, essentially demonstrating that the birds
“whistle” the formants and transitions of human speech creating speech-like
song patterns. This is always fun,
especially when they match the bird’s “speech”
patterns to the voice of the human the bird loves and mimics.
A variation on this research was
conducted by a grad student at the insistence of another professor, who was
persuaded her dog could speak. Actually,
her dog did a remarkable job of producing sound sequences that mimicked the
prosodic patterns used by its owner. The
dog used rising inflections to create patterns that sounded like questions. He also used falling to flat inflections to
create negative responses, including his consistent response to the question, “Do you want a bath?” In almost all cases
of pet speech, it is true that the human is better at understanding the pet’s
utterances, than the pet is at speaking.
CRABS
I got mixed up with crabs because a young
biologist believed that some of the sounds crabs use for communicating are
produced by vibrating their respiratory apparatus rather than using their
claws. This contradicted the accepted theories of crab communication. The
trouble was, the crabs only produce these particular sounds when they are
secure inside their darkened burrows, and only then if the moon is full. I know it sounds crazy, but it has something
to do with moon and tides.
Now if you have never listened to the
sounds that crabs produce for one another in the dark depths of their burrows,
you haven’t lived. Once we figured out
how to record the crab sounds, it was easy to prove they were indeed vibratory
and not made with the claws.
Unfortunately, I was left to spend the rest of my days wondering exactly
what those crabs were doing in that dark burrow in the full moon while
whistling through their gills.
CRYING BABIES
Among the human sounds I never intended
to study are babies crying and old men snoring, but I have spent more hours
than I care to admit on each of these. A
friend collected audio recordings of babies crying. Some of the babies could hear, while others
were deaf. My task was to sort the recordings,
attempting to identify the deaf babies.
The crying of deaf babies differed from that of hearing infants, even at
very early ages, and we identified perceptual and acoustic correlates.
In the early 1980’s when Sudden Infant Death Syndrome (SIDS) was poorly
understood, a colleague, Ray Colton, obtained recordings of an infant who later
died of SIDS. While the child’s death
was tragic, the inadvertent existence of the recordings offered an invaluable
opportunity to study possible differences between the vocal tract of the SIDS
baby and normal babies. His analyses of
the child’s recordings demonstrated differences that led to better
understanding, and eventually to screening and monitors. While writing this, I did a Google search,
and discovered that the study of infant crying as a diagnosis or screening for
SIDS is still a hot research topic.
FALSE TEETH
A young dentist specializing in
prosthetics persuaded me to help him determine whether an upper denture plate
imprinted with textured rugae, which felt like a human hard palate (the roof of
your mouth), would help a wearer speak more clearly than a slick, smooth
denture plate. Actually, the rugae help,
but not a whole lot.
SNORING
But the most disillusioning study I ever
pursued was conducted in collaboration with a young pulmonology resident. The problem of sleep apnea had been
recognized, and sleep laboratories were being built to diagnose the
disorder. Many labs had long waiting
lists, and patients faced long delays before they could be tested.
The pulmonology resident believed that
patients with sleep apnea had a different sound to their snoring than patients
who snored, but didn’t have sleep apnea.
He believed that acoustic recordings of a patient’s snoring could be
used as a screening test to identify patients at greatest risk for apnea.
He secured recordings of about a hundred
patients snoring in the sleep lab of a local V.A. Hospital (hence all
men). We used a sample of ten (five with
and five without sleep apnea) to determine the acoustic correlates. Then we used the whole group to see if our
identified acoustic measures would reliably sort the patients into those with
and those without sleep apnea. It
worked. The sleep apnea patients
demonstrated a pattern never heard in the non-apnea patients – a period of
absolute silence (during the collapse of their vocal tract) followed by a brief
very high pitched whistle (sometimes above the frequency of human hearing) as
the closed tract popped open and the first air was forcefully sucked through a very
narrow opening. We were elated. We had an inexpensive, highly reliable
screening test for sleep apnea.
My colleague’s committee approved his
research and he became a full-fledged pulmonologist. He gave the paper at a highly prestigious
conference, and the abstract was published.
Absolutely nothing ever happened.
No one used the approach; no one even bothered to try to disprove
it. The reason was simple. Hundreds of sleep labs were being built, equipped,
and staffed. Overnight tests for apnea
are expensive and lucrative. The medical
world didn’t want a cheap substitute (even as a screening tool) for their
high-priced evaluations. The only
positive outcome of this research is highly personal. I can listen to you snore and tell you if you
have sleep apnea. It is a highly over-rated, and under utilized accomplishment,
only slightly more useful than the ability to mimic amorous crabs.
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