Sunday, January 31, 2016

SOUNDS OF MY LIFE -- MY LIFE IN STORIES (Frances Jackson Freeman)

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:
            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.
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.
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.
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.
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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