Positive/ Negative Practice

This behavioral treatment is prescribed primarily for patients with nonorganic voice disorders. A patient with a nonorganic voice disorder has been diagnosed with aberrant voice production due to the abnormal use of a normal mechanism, often due to stress or some sort of secondary gain. She or he may have been ‘stuck’ with the abnormal voice for months to years, or may lurch between normal and abnormal voice production on an apparently involuntary basis. To help patients first “find” their normal voices, the clinician guides the patient through a variety of vocal elicitations such as: a yell, glissando, siren, or vocal fry. All of this may be with or without clinician digital manipulation of the laryngeal framework.

After preliminarily ‘settling in’ the patient’s reestablished normal voice, the clinician quickly asks the patient to alternate between the re-established normal voice and the old abnormal voice. First, the patient alternates upon clinician cue, again optionally with or without digital manipulation, and then the patient demonstrates the ability to switch between the two kinds of voice production at the sentence level, and then every few words, and then word-by-word. The positive and negative practice demonstrates mastery / control over the abnormal/ nonorganic voice production.

If possible, this process should occur with patient, clinician, and family/ friends in attendance. Other doctors, speech pathologists, pulmonologists, and allergists who may have previously attempted to help the patient using medical rather than behavioral treatments should also be made aware of the nature of the patient’s diagnosis, the purely behavioral approach to it, and the idea that behavioral intervention to resolve this problem completely should not normally exceed three visits to a speech pathologist, to avoid his or her becoming a co-dependent or source of secondary gain.

Listen to a few demonstrations below:

Mucosal Chatter

Mucosal chatter is an audible phenomenon of injured vocal cord vibration. It is commonly heard in the softly-sung upper voice of persons with nodules, polyps, etc.

Hoarseness or roughness are broad and nonspecific descriptors useful only for severe injuries. Small injuries that are nevertheless impairing the singing range may leave the speaking voice sounding normal. I suppose “hoarseness of singing range” could be used, but again, that would be an unsophisticated and basic description of vocal phenomenology. To hear more useful phenomena of injury, we elicit and thereby investigate the upper range of singing (even in nonsingers) because high, soft singing makes the phenomenology apparent.  This is why we have described “vocal cord swelling checks” and created a video to teach how to elicit them, and also how to evaluate and communicate the phenomenology that results. In particular, delays of phonatory onset (“onset delays”) above approximately C5 (523 Hz) may indicate mucosal injury even when speaking voice sounds normal. Also heard is air-wasting, where there is a “scratchiness” to the excess airflow. Segmental vibration is also a common audible phenomenon of a mucosal disorder can also be easily taught and recognized.

Vocal cord mucosal chatter adds an extremely rapid “shudder” on top of the pitch of the voice. I have used “chatter” rather than “shudder” because the latter suggests a lower frequency than the former. It could be called a very fine-grained diplophonia…but typical diplophonia, caused by independent vibrating segments, is a much grosser vocal phenomenon. While chatter is more subtle, once it is pointed out and taught briefly, most people can easily distinguish between onset delays, diplophonia, segmental vibration, the transient “squeaking” of a micro-segmental vibration,  the crackling sound of mucus dancing on the vocal cords, and “chatter.”  Those who master recognition of these phenomena can easily communicate them to colleagues. For our purposes, let me stress again that the above phenomena—and chatter in particular—do not happen in the normal larynx, where vocal cord margins match perfectly and the mucosa oscillates normally.  When heard—even in the person with a normal speaking voice—the examiner can strongly suspect a mucosal abnormality even before examining the vocal cords.  In fact, where these phenomena are heard and initial examination looks normal, it would be a good idea to “look harder.”

Patient examples:


Segmental Vibration

In the normal larynx, both chest and falsetto (head) registers are produced by vibration of the anterior 2/3 of the vocal cords. The posterior 1/3 is “inhabited” by the arytenoid cartilage and does not vibrate.

In certain pathological circumstances such as displayed in the photo sequences below, only a small part of the vocal cords vibrates.

This segmental vibratory phenomenon is typically seen in vocal cords that are damaged—such as by vocal nodules, polyps, cyst, scarring, etc. In such persons, upper voice is typically particularly impaired, until, as the person continues to try to ascend the scale, suddenly a crystal-clear “tin whistle” kind of voice emerges and may continue upwards to very high pitches.

Some in the past have talked about flagelot, flute, bell, or whistle register.  We suspect that this was in the days before videostroboscopy and at least in some cases may have been segmental vibration.

The best way to determine if what sounds like a “tin whistle” upper voice extension is due to segmental vibration is by videostroboscopic examination during that kind of phonation. The other way is for the individual to produce their “tin whistle” kind of voice very softly and then try to crescendo. If full length vibration, smooth crescendo will be possible. If segmental, there will be a sudden “squawk” as the vocal cords try to go (unsuccessfully) from segmental to full-length vibration.


Vocal instability

This characteristic might manifest most clearly during sustained phonation as a glitch, catch, wavering, tremor, in-and-out vocal fry, or other such finding. In each case, the patient would be unable, partially able, or only intermittently able to produce a steady and predictable voice.

Dystonic tremor of the voice or larynx

A tremor that sometimes accompanies laryngeal dystonia and its effects on voice function (spasmodic dysphonia), breathing function (respiratory dystonia), or both. This dystonic tremor is heard as a “wavering” in the voice (if the person has spasmodic dysphonia) or in the sound of inhaled or exhaled air (if the person has respiratory dystonia), or it can be detected in both the voice and the sound of inhaled or exhaled air (if the person has both spasmodic dysphonia and respiratory dystonia). A patient who exhibits this kind of tremor in tandem with spasmodic dysphonia, for example, may be described by the examining clinician as having “spasmodic dysphonia with a small/moderate/large/overwhelming tremor component.” Dystonic tremor can also appear in other parts of the body (e.g., as head or limb movements) when a person’s dystonia affects those parts, but our focus here is on dystonia of the larynx.

Voice-affecting dystonic tremor might sometimes be mistaken for the tremor induced by a different neurological disorder, essential voice tremor. If one knows what to listen for, however, it is usually possible to distinguish dystonic tremor from the tremor induced by essential voice tremor. Most obviously, dystonic tremor is almost always accompanied by other manifestations of dystonia, such as phonatory arrests, dropouts to a whisper, or squeezedowns. Dystonic tremor may worsen under specific circumstances—with stress, fatigue, or during telephone use, for example. Dystonic tremor is often (though not always) more pronounced in the patient’s chest register voice than falsetto register voice—sometimes dramatically so—and this difference might be heard when the patient is asked to sustain a single sung note as steadily as possible. Finally, dystonic tremor’s amplitude can vary from cycle to cycle; to use singers’ parlance, it is as though a couple of cycles of “wild” vibrato are followed by a few cycles of merely wide vibrato, followed by a second or two of much more stable voice. In the occasional case, however, a patient’s tremor is so overwhelming and these distinctive qualities of dystonic tremor so subtle that the clinician proceeds initially with a working, rather than settled, diagnosis.

Vocal Tremor

Vocal tremor: A regular, wavering quality of voice, analogous to a singer’s vibrato but occurring, to an individual’s distress, during speaking, not just during singing. May occur as a sole abnormality in essential voice tremor, or in combination with spasmodic dysphonia.

Teaching demonstration (mimicked):

Patient example dystonic tremor: Note accompanying squeezedowns and difference in two registers

Vocal fry

The name given to a quality of sound produced at low pitch (generally below 70 Hz, or around E2 or F2 in musical notation). Vocal fry is produced in what some call pulse register, as compared with chest and falsetto registers. Once defined with the help of audible examples, most individuals can readily identify this quality of voice. It may be heard in poorly produced voices; in other cases, it is used intentionally as a training technique, particularly for air-wasting dysphonia that has a functional cause.