Psychogenic movement disorders: Past developments, current status, and future directions

Abstract

As the field of movement disorders has developed and matured over the past 25 years, psychogenic movement disorders have become increasingly recognized in subspecialty clinics. The diagnosis can be challenging and should be based on positive features rather than a purely exclusionary approach. The clinical phenotype can be quite varied, although certain categories of abnormal movement are more common than others. Electrophysiological studies may be particularly useful in establishing the diagnosis, especially with respect to tremor and myoclonus, and an argument can be made for adding a "laboratory-supported definite" category to earlier classification schemes. The diagnosis of psychogenic dystonia remains a major challenge, although there are some recent promising developments with respect to the evaluation of cortical plasticity that require further study. The pathogenesis of psychogenic movement disorders is poorly understood; insights may be provided from the study of other neurological conversion disorders such as psychogenic hemiparesis. Psychogenic movement disorders typically result in considerable disability and negatively impact quality of life to the same or greater extent than do many organic movement disorders. Treatment is extremely challenging, and many patients experience chronic disability despite various therapeutic interventions. Given the personal and societal impact of these problems, further advances in our understanding of their pathogenesis and the subsequent development of effective therapies are sorely needed.

A retrospective study of the clinical and electrophysiological characteristics of 32 patients with orthostatic myoclonus

“…A functional gait disorder was at least probable in 16% of NOH patients. 20, 21 Finally, the use of medications overall known to potentially cause myoclonus was similar between the OM and NOH cohorts. A full list of the medications taken by the patients in this study can be found in Supplementary Table 2.…”

Sensory aspects of movement disorders

“…Because only a small group of patients develop dystonia in the setting of CRPS, some genetic predisposition might exist in patients who do develop this form of peripherally induced dystonia. 140 The presence of affective disorders and of psychogenic features in these patients has led some researchers to propose that dystonia in the setting of peripheral injury is largely of psychogenic origin 137,143 or a form of body integrity identity disorder. 144 More data are needed to better understand the CRPS dystonia syndrome.…”

Pharmacotherapy of Essential Tremor

“…Its diagnosis is based on a sudden onset, irregular and inconsistent oscillatory movements with distractibility and suggestibility. Entrainment, defined as changing frequency of psychogenic tremor in adaption to voluntary tasks with determined frequency and performed with controlateral arm such as tapping in time to a metronome, can be very helpful in differentiation from ET 41. Multiple somatization signs, previous psychiatric diagnoses, and possible secondary gain can be also helpful for the diagnosis of psychogenic tremor 42…”