How much talking does it take to teach?
Judging by their frequency as voice center clients, teachers have long been identified as professionals at "high vocal risk." While a number of factors explain why teachers have more voice problems than other workers, it is clear that - at the top of the list - teachers simply must use their voices frequently to get the job done.
In order to study occupational voice use in a methodical way, researchers at the National Center for Voice and Speech developed technology to determine just how much teachers talk. Nearly 100 teachers in the Denver, Colorado, area schools volunteered to wear a specially programmed device to measure their voice use. This device, called a dosimeter, uses a wire attached to the teacher's throat to transmit volume, pitch and duration of speech to a specially programmed pocket PC.
While researchers
are still sifting through the results, their suspicion that teachers' vocal
folds get a rigorous workout each day is confirmed.
The dime-sized vocal folds of teachers go through more than 1 million cycles
of vibration each day. That translates into about 1-1/2 hours of pure voicing
time in a 12-hour period. But, don't teachers speak for more than 1-1/2 hours
each day?
Consider that the
dosimeter measures only the time that the vocal folds are in vibration. That
means that pauses between words, at the end of sentences or while listening
aren't accumulated by the dosimeter. Surprisingly, those small time gaps add
up. Consider that in a one-minute monologue, the vocal folds are in vibration
only 33.6 seconds - or about half the monologue.
According to the
study's lead investigator, Dr. Ingo Titze, the cumulative speaking time of 90
minutes within a 12-hour day does, indeed, show that teachers use their voices
more rigorously than other professionals. "Consider that if we counted
the vibrations of the vocal folds as distance traveled, this could easily exceed
1 kilometer per hour of pure voicing."
Teachers can
learn to care for their speaking voices at the Voice Academy: a cost-free, virtual
school created solely for the vocal health of teachers (www.voiceacademy.org).