Affective Loss of Tonus

AFFECTIVE LOSS OF TONE

Affective (or hysterical) loss of tone is a condition in which the muscles of the face and body become weak, painful, or immobile. This can lead to changes in facial expression and limited movement and activity. Affective loss of tone is a common condition that can manifest in various forms, including cataplexy and peripheral neuropathy.

CHARACTERISTICS AND CLASSIFICATION

The most well-known manifestation of affective loss of tone is cataplexy, which is accompanied by a sudden and short-term (usually less than 6 seconds) cessation of muscle tone in the entire body or only part of it. The muscles of the face (mental, brow, chewing) are predominantly affected, but sometimes other muscles of the trunk, limbs and head are also affected. If this condition persists for a long time, more serious forms of nervous system pathology, for example, parkinsonism, may develop.

There are 3 main forms of cataplexy:

1. Tension cataplexy occurs due to a mental trigger. It is usually caused by a bright and unexpected sight (for example, the work of a fireman, rescuer), stress or fear. During an episode, muscle contractions in response to stress or pain may stop before reaching normal levels (ie, involuntary muscle contraction suddenly stops). As a rule, these episodes are short - about 5 seconds and do not occur very often. If cataplexy is caused by emotional stress, it may be accompanied by subsequent hysterical inhibition syndrome and lethargy. 2. Psychotic cataplexy is also known as psychogenic cataplexy. This form is associated with the characteristics of the patient’s mental functions and occurs in the event of the manifestation of various emotions and character traits. This usually happens when there is expressed fear or when a person experiences frightening experiences. Like stress cataplexy, it manifests itself with sudden episodes of motor blocking. The main difference here may be the reduction in seizure time. It can last from 0.5 to 3 seconds. 3. Cataplectic attacks can occur independently without any additional factors. Then they may not be directly related to emotions and stress experienced. The duration of such attacks can range from 20-30 seconds. Such cases of cataplexy are believed to be the result of psychophysiological disturbances and a poorly understood pathophysiological mechanism.