When you suffer from spasmodic dysphonia there is a problem with the learned skill of speaking. The
cells in the brain where the learned controls of the vocal chords muscles situate, are damaged.
The muscles that open or close the vocal chords in a smooth and controlled way, are receiving
scrambled signals. The signals that are being sent to the voice muscles normally do not operate like an on or off
switch. The activation of the muscles that close or open the vocal chords goes normally in a very
smooth and controlled way.
The brake is busted
All the muscles in your body receive two signals at the same time. You can compare it to your
car’s gas pedal and the brake. They receive an activation signal accompanied by an slow down
signal. If the activation signal is stronger then the slow down signal, the muscle contracts. The
more slow down signal there is, the less the muscle contracts.
On or off
When you suffer from spasmodic dysphonia there is a problem with the brain cells that produce
the slow-down signal. The muscles do not operate in a smooth way anymore, but they contract
like an on-off switch. It is like pressing the gas pedal fully down fast with your foot, while your
brake is not functioning anymore. And then releasing it in an instant. Your car will move in a very
jerky way. It is all or nothing.
All or nothing
This is exactly the problem with the muscles that move your vocal chords.
They go all the way open or all the way shut.