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Related to Lability: Emotional lability


Very rapid fluctuations in intensity and modality of emotions; seen in the affective reaction or in certain organic brain disorders.



in physiology, functional mobility; the speed of flow of elementary cycles of excitation in nerve and muscle tissues.

The concept of lability was introduced by the Russian physiologist N. E. Vvedenskii (1886), who considered its measure to be the greatest frequency of tissue irritation possible without a change in rhythm. A tissue’s lability reflects the time necessary to restore the tissue’s work capacity after an excitation cycle. The greatest lability is found in the processes of the nerve cells, the axons, which are capable of reproducing as many as 500 or 1,000 impulses per sec. The central and peripheral sites of contact, or synapses, are less labile (for example, a motor nerve ending can transmit no more than 100–150 excitations per sec to a skeletal muscle).

Inhibition of the vital activities of tissues and cells (for example, by means of cold or narcotics) decreases lability, since the restorative processes are retarded thereby and the refractory period prolonged. The lability value is variable. Thus, the refractory period is shortened in the heart under the influence of frequent stimuli: its lability is increased. This phenomenon is the basis for what is called the assimilation of rhythm. The concept of lability is important to an understanding of the mechanisms of nervous activity, and of the operation of the neural centers and analyzers under both normal and pathological conditions.

In biology and medicine, the term “lability” refers to instability or variability, such as of the psyche, the physiological state, the pulse, or the body temperature.


Vvedenskii, N. E. Poln. sobr. soch, vols. 1–2. Leningrad, 1951–52.
Ukhtomskii, A. A. Sobr. sock, vol. 2. Leningrad, 1951.
Golikov, N. V. Fiziologicheskaia labil’nost’ i ee izmeneniia priosnovnykh nervnykh protsessakh. Leningrad, 1950.


References in periodicals archive ?
Health care providers should always consider the possibility of PBA when patients with neurological conditions present with symptoms of emotional lability.
They are characterized by tendency to compensatory exalted self-affirmation in a communication, going beyond the problems associated with their own disease, as evidenced by the high indicators of anxiety scales and sensitivity combined with a moderate level of lability, extroversion, and compromise.
Common misinterpretations of the disturbance by the sufferers are remedied by ascribing emotional lability to a physical cause, which relieves a great deal of psychological suffering from the misdiagnosis of a previously intractable "unknown mental illness".
Meanwhile, when considering the relationship between tacit psi scores and the lability construct, Luke and Morin (2009) failed to find significant correlations between precognitive performance and either of the subscales of the Creative Cognition Inventory (linear subscale: r = .
The first factor included sleep-wake cycle disturbances, perceptual disturbances, delusions, lability of affect, motor agitation, fluctuation of symptom severity, and inverse of motor retardation; it was therefore named as the psychotic and motor symptoms factor.
In our sample we have almost the same percentage of emotional lability for teachers from urban, rural and high schools.
Sustainable "green" elements being incorporated into the development include certified construction waste management; the use of low emitting materials including adhesives, paints, and carpet; sophisticated lighting and HVAC design focused on control lability of systems by users; a reflecting white roof; water efficient landscaping; and alternative transportation focused on bicycle racks and showers for tenant employee use.
In short, the premises lability claim should not have been dismissed under the motion for summary judgment.
The prescribing information states that the product has not been shown to be safe or effective for treating other types of emotional lability that affect people with Alzheimer's disease or other dementias.
Patients with delirium can present with agitation, sleep-wake cycle disturbances, including diurnal variation and lability of mood (1).
She describes the accompanying obsessive compulsive disorders, emotional lability, childhood regression and stress of all this on the child and the rest of the extended family.