Changes to the voice happen frequently with a number of minor illnesses. Most of us have experienced having a ‘croaky’ voice, a ‘frog in the throat’ or even losing our voice entirely, usually when we have an infection in the throat or have overused our voice.
But sometimes a change in the voice can be a sign of a more serious problem.
The sounds we make when we speak or sing are produced in the larynx, sometimes called the voice box, a structure situated in the throat between the back of the tongue and the trachea (windpipe). The larynx is surrounded by a framework of cartilage that is noticed as the Adam's apple in the throat.
Every breath of air going to and from the lungs passes through the larynx. The space inside the larynx is called the glottis and it is here that the voice is produced. Two bands of elastic tissue — the vocal cords — are attached to the wall of the glottis by tiny muscles. Air passing through the tiny gap between the vocal cords sets them vibrating and produces a sound.
Changes in the shape of this gap, by a person's ability to move their vocal cords, will produce changes in the pitch (highness or lowness) of the sound produced. This is very similar to the way a musical wind instrument works. The shape of the person's throat, nose and mouth determines the quality of the sound, which is why everyone's voice is different.
Causes of voices changes
It is clear that anything that affects the size and shape of the vocal cords, or interferes with air passing through them, will affect the voice.
Causes of voice changes include the following.
- Inflammation of the larynx — laryngitis. Many minor infections can cause temporary inflammation and swelling of the cords, known as laryngitis, producing a hoarse voice. Straining your voice can also cause hoarseness for a few days. This can become a chronic problem for people who: have allergies; are exposed to smoke; have problems with reflux (gastro-oesophageal reflux disease); drink alcohol excessively; or use their voice excessively (for example, singers or teachers).
- Growths may occur on the vocal cords. These may be harmless cysts or polyps, or cancerous growths.
- Hormone changes can affect the voice. This is why boys' voices ‘break’ around puberty and some pregnant women notice a deeper voice. Lack of thyroid hormone sometimes causes swelling of the vocal cords and a husky voice.
- Damage to the nerves to the larynx can interfere with movement of the vocal cords and affect speech.
If you, or someone you know, has had a persistent change to their voice it is wise to seek medical advice to be sure there is no serious cause.
2. NHS Choices. Laryngitis (updated 18 Sep 2013). http://www.nhs.uk/conditions/Laryngitis/Pages/Introduction.aspx (accessed Nov 2013).
3. US National Library of Medicine; National Institutes of Health. MedlinePlus. Hoarseness (updated 9 Nov 2012). http://www.nlm.nih.gov/medlineplus/ency/article/003054.htm (accessed Nov 2013).