Let’s think about why voice quality changes as we grow and as we get older.
The larynx and phonatory system changes hugely over the course of a lifetime.
At birth the vocal cords are 3mm long and the mucosal covering of the folds is thick and loose. The vocalis muscle fibres are incomplete.
In early childhood the layers of vocalis muscle become more differentiated and the histology develops. The whole larynx descends from C1-C4. The complexity of sound a child can produce becomes more sophisticated. Between 5 and 8 years old pitch can extend to a two and a half octave range. Vocal differences between the sexes will begin to occur.
In adolescence, the male larynx changes dramatically due to body growth and hormonal influence. The vocal folds double in length reaching an adult size of 17mm or more. The thyroid cartilage tips forward at an angle creating the Adam’s Apple. Modal pitch drops.
The female voice will also deepen from childhood through adolescence due to general body growth.
The adult larynx reaches mature final histological make up and differentiation of the structural layers at around 16 years old and will sit at a level between C3 and C6.
Towards the end of middle age in women, hormonal changes can cause the vocal folds to thicken and stiffen and pitch might be lower. Men are more likely to notice an increase in pitch after middle age as the vocal folds loose some bulk becoming thinner.
Into old age as the layers thin and the vocalis muscle can atrophy and thin out, the vocal cords can bow and vibrate differently. Presbylarynx leads to higher, often unstable pitch and a weaker, breather voice. Laryngeal cartilages can also calcify with age and the cricoarytenoid joints can stiffen making it harder to close the vocal cords.
For the most part ageing voice changes are gradual and are not seen or heard as abnormal. If it changes someone’s voice and affects quality of life impacting on every day responsibilities or hobbies then help can be sought from a voice specialist speech therapist. If you’re worried about your voice, first step speak to your GP.