Neural correlates of conversion disorder: overview and meta-analysis of neuroimaging studies on motor conversion disorder

Abstract

BackgroundConversion Disorders (CD) are prevalent functional disorders. Although the pathogenesis is still not completely understood, an interaction of genetic, neurobiological, and psychosocial factors is quite likely. The aim of this study is to provide a systematic overview on imaging studies on CDs and investigate neuronal areas involved in Motor Conversion Disorders (MCD).MethodsA systematic literature search was conducted on CD. Subsequently a meta-analysis of functional neuroimaging studies on MCD was implemented using an Activation Likelihood Estimation (ALE). We calculated differences between patients and healthy controls as well as between affected versus unaffected sides in addition to an overall analysis in order to identify neuronal areas related to MCD.ResultsPatients with MCD differ from healthy controls in the amygdala, superior temporal lobe, retrosplenial area, primary motor cortex, insula, red nucleus, thalamus, anterior as well as dorsolateral prefrontal and frontal cortex. When comparing affected versus unaffected sides, temporal cortex, dorsal anterior cingulate cortex, supramarginal gyrus, dorsal temporal lobe, anterior insula, primary somatosensory cortex, superior frontal gyrus and anterior prefrontal as well as frontal cortex show significant differences.ConclusionsNeuronal areas seem to be involved in the pathogenesis, maintenance or as a result of MCD. Areas that are important for motor-planning, motor-selection or autonomic response seem to be especially relevant. Our results support the emotional unawareness theory but also underline the need of more support by conduction imaging studies on both CD and MCD.

Multimodal Brain Analysis of Functional Neurological Disorders: A Functional Stroke Mimic Case Series

“…In line with previous studies [1,2], we postulate that functional stroke mimics are specifically determined by a dysfunction in high-order associative areas along with the subsequent perturbation of motor/premotor areas.…”

“…Functional neurological disorders (FND) are characterized by neurological symptoms that cannot be attributed to an organic brain aetiology, but rather that can be associated with emotional stressors acting as precipitating factors [1,2]. Different terms have been used, including conversion disorder and psychogenic or dissociative neurological symptoms [1].…”

“…Different terms have been used, including conversion disorder and psychogenic or dissociative neurological symptoms [1]. …”

“…In line with other psychiatric disorders, functional stroke mimics would be the result of genetic, neurobiological, and psychosocial determinants [1]. In the last decade, resting-state functional MRI (rs-fMRI) and transcranial magnetic stimulation (TMS) have been proposed as in vivo and non-invasive tools to study intrinsic brain connectivity and vulnerability of the human brain.…”

Functional neuroimaging of recovery from motor conversion disorder: A case report

“…Functional neuroimaging studies have demonstrated a failure to activate contralateral motor (Marshall et al, 1997;Stone et al, 2007) and premotor cortex during action execution, action selection (Voon et al, 2011), movement observation (Burgmer et al, 2006) and during recall of clinically repressed events (Kanaan et al, 2007) in affected patients. In addition, prefrontal areas, insula, amygdala and anterior cingulate cortex have been implicated in motor conversion disorder (Boeckle et al, 2016).…”