Shortly after I began researching the world of Manuel García and Pauline Viardot-García, I learned that their student Anna E. Schoen-René (who taught Margaret Harshaw and many other successful students) was very much against the idea of yawning in the voice studio. Her observation was that yawning - in any denomination - stiffened the larynx. That's interesting, I thought.

Tucking this nugget of information away, I didn't think much about it, perhaps, because I never really warmed to the idea of yawning in the first place. There are many who do however, often taking pains to point out that it is the beginning of a yawn that is beneficial. They believe it opens the throat.

But what about the ear? Is it open during a yawn? This is what I started thinking about when I found myself yawning and - momentarily - going deaf. Of course, you've undoubtedly experienced this, but probably weren't aware of it since the moment passes quickly. But it really does happen. We go deaf when we yawn big. Here's why.

• The ear drum can only vibrate freely when the pressure on either side of it is similar.

• The eustachian tube regulates the pressure of the middle ear.

• During a yawn, the eustachian tube opens which stretches the muscle of the eardrum - the tensor tympani. This stretching prevents the eardrum from vibrating freely.

• Between the slight change in air pressure and the tensor tympani muscle being stretched, vibration is not able to enter the middle and inner ear.

• Voila! The yawning person is deaf!

In light of this information, I posit that yawning while singing is like driving a car with the brakes on, which compromises the singer's audio-vocal control. Perhaps Madam Schoen-René was on to something after all, since the larynx is neurologically connected to the ear via the vagus nerve. Now, ain't that something?