If you examine the temporal bones on the base of the skull, you’ll see that there are two small spikes, called the styloid processes, that are set in from the sides of the skull and so are not visible or palpable. Just about the larynx is a horseshoe-shaped bone, called the hyoid bone, that forms the base of the tongue (it is sometimes called the “tongue bone”). The hyoid bone is suspended from the styloid processes by muscles, and the larynx is suspended from the hyoid bone and from the styloid processes. It is also anchored to the sternum below and the throat behind, so that it is literally suspended within a muscular scaffolding, sometimes called the suspensory muscles of the larynx, which antagonistically support it from various directions.
This extrinsic musculature forms a crucial part of the singing and speaking apparatus. When we hear a tenor sing a high note, these muscles antagonistically pull from different directions to maintain stretch on the larynx in order for it to function optimally. You can see the action of these extrinsic muscles when you sing up a scale: in most people the larynx will visibly ascend with the rising notes as a result of overactivity of the muscles that elevate the hyoid bone and larynx. A trained singer is able to activate the suspensory muscles that support the larynx in a balanced way so that it is antagonistically pulled upon from several directions, which has a very marked effect on timbre, resonance, and vocal range. The ability of the larynx to work properly, as well as the ability to sing with an “open throat,” depends to a large extent on the proper working of these suspensory muscles of the larynx and their relation to our upright posture.
In contrast, a singer who tends to drag on the throat, or who collapses in this region, will not be able to maintain an open throat, and will also have more trouble activating or “erecting” the vocal mechanism during singing, which means that the suspensory muscles will not adequately perform their duty and that the voice will lose in strength and flexibility. In order to function properly, the larynx must be suspended freely from the skull without upsetting the necessary balance of the head on the spine, gaining its support from the larger upright system rather than interfering with it. The throat remains open, and the suspensory musculature of the larynx is able to naturally “erect” the vocal mechanism. In tenors with pillar-like necks, for instance, the neck and throat muscles are naturally well-developed and provide a stable support for the larynx. The throat is then open and free, and the larynx can be brought into suspension for the athletic activity of singing with little effort.
Dimon, Theodore. Your Body, Your Voice: The Key to Natural Singing and Speaking. North Atlantic Books, 2011.