Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
84
result(s) for
"Conversion Disorder - diagnostic imaging"
Sort by:
Cingulo-insular structural alterations associated with psychogenic symptoms, childhood abuse and PTSD in functional neurological disorders
2017
ObjectiveAdverse early-life events are predisposing factors for functional neurological disorder (FND) and post-traumatic stress disorder (PTSD). Cingulo-insular regions are implicated in the biology of both conditions and are sites of stress-mediated neuroplasticity. We hypothesised that functional neurological symptoms and the magnitude of childhood abuse would be associated with overlapping anterior cingulate cortex (ACC) and insular volumetric reductions, and that FND and PTSD symptoms would map onto distinct cingulo-insular areas.MethodsThis within-group voxel-based morphometry study probes volumetric associations with self-report measures of functional neurological symptoms, adverse life events and PTSD symptoms in 23 mixed-gender FND patients. Separate secondary analyses were also performed in the subset of 18 women with FND to account for gender-specific effects.ResultsAcross the entire cohort, there were no statistically significant volumetric associations with self-report measures of functional neurological symptom severity or childhood abuse. In women with FND, however, parallel inverse associations were observed between left anterior insular volume and functional neurological symptoms as measured by the Patient Health Questionnaire-15 and the Screening for Somatoform Symptoms Conversion Disorder subscale. Similar inverse relationships were also appreciated between childhood abuse burden and left anterior insular volume. Across all subjects, PTSD symptom severity was inversely associated with dorsal ACC volume, and the magnitude of lifetime adverse events was inversely associated with left hippocampal volume.ConclusionsThis study reveals distinct cingulo-insular alterations for FND and PTSD symptoms and may advance our understanding of FND. Potential biological convergence between stress-related neuroplasticity, functional neurological symptoms and reduced insular volume was identified.
Journal Article
Corticolimbic fast-tracking: enhanced multimodal integration in functional neurological disorder
by
Jalilianhasanpour, Rozita
,
Diez, Ibai
,
Keshavan, Matcheri S
in
Adult
,
Amygdala
,
Amygdala - physiopathology
2019
ObjectiveSome individuals with functional neurological disorder (FND) exhibit motor and affective disturbances, along with limbic hyper-reactivity and enhanced motor-limbic connectivity. Given that the multimodal integration network (insula, dorsal cingulate, temporoparietal junction (TPJ)) is implicated in convergent sensorimotor, affective and interoceptive processing, we hypothesised that patients with FND would exhibit altered motor and amygdalar resting-state propagation to this network. Patient-reported symptom severity and clinical outcome were also hypothesised to map onto multimodal integration areas.MethodsBetween-group differences in primary motor and amygdalar nuclei (laterobasal, centromedial) were examined using graph-theory stepwise functional connectivity (SFC) in 30 patients with motor FND compared with 30 healthy controls. Within-group analyses correlated functional propagation profiles with symptom severity and prospectively collected 6-month outcomes as measured by the Screening for Somatoform Symptoms Conversion Disorder subscale and Patient Health Questionnaire-15 composite score. Findings were clusterwise corrected for multiple comparisons.ResultsCompared with controls, patients with FND exhibited increased SFC from motor regions to the bilateral posterior insula, TPJ, middle cingulate cortex and putamen. From the right laterobasal amygdala, the FND cohort showed enhanced connectivity to the left anterior insula, periaqueductal grey and hypothalamus among other areas. In within-group analyses, symptom severity correlated with enhanced SFC from the left anterior insula to the right anterior insula and TPJ; increased SFC from the left centromedial amygdala to the right anterior insula correlated with clinical improvement. Within-group associations held controlling for depression, anxiety and antidepressant use.ConclusionsThese neuroimaging findings suggest potential candidate neurocircuit pathways in the pathophysiology of FND.
Journal Article
Impaired awareness of motor intention in functional neurological disorder: implications for voluntary and functional movement
2017
Functional neurological disorders (FNDs), also known as conversion disorder, are unexplained neurological symptoms unrelated to a neurological cause. The disorder is common, yet poorly understood. The symptoms are experienced as involuntary but have similarities to voluntary processes. Here we studied intention awareness in FND.
A total of 26 FND patients and 25 healthy volunteers participated in this functional magnetic resonance study using Libet's clock.
FND is characterized by delayed awareness of the intention to move relative to the movement itself. The reporting of intention was more precise, suggesting that these findings are reliable and unrelated to non-specific attentional deficits. That these findings were more prominent with aberrant positive functional movement symptoms rather than negative symptoms may be relevant to impairments in timing for an inhibitory veto process. Attention towards intention relative to movement was associated with lower right inferior parietal cortex activity in FND, a region early in the processing of intention. During rest, aberrant functional connectivity was observed with the right inferior parietal cortex and other motor intention regions.
The results converge with observations of low inferior parietal activity comparing involuntary with voluntary movement in FND, emphasizing core deficiencies in intention. Heightened precision of this impaired intention is consistent with Bayesian theories of impaired top-down priors that might influence the sense of involuntariness. A primary impairment in voluntary motor intention at an early processing stage might explain clinical observations of slowed effortful voluntary movement, heightened self-directed attention and underlie functional movements. These findings further suggest novel therapeutic targets.
Journal Article
Functional neuroimaging of recovery from motor conversion disorder: A case report
by
Dogonowski, Anne-Marie
,
Andersen, Kasper W.
,
Schreiber, Karen
in
Adult
,
Brain injury
,
Brain mapping
2019
A patient with motor conversion disorder presented with a functional paresis of the left hand. After exclusion of structural brain damage, she was repeatedly examined with whole-brain functional magnetic resonance imaging, while she performed visually paced finger-tapping tasks. The dorsal premotor cortex showed a bilateral deactivation in the acute-subacute phase. Recovery from unilateral hand paresis was associated with a gradual increase in task-based activation of the dorsal premotor cortex bilaterally. The right medial prefrontal cortex displayed the opposite pattern, showing initial task-based activation that gradually diminished with recovery. The inverse dynamics of premotor and medial prefrontal activity over time were found during unimanual finger-tapping with the affected and non-affected hand as well as during bimanual finger-tapping. These observations suggest that reduced premotor and increased medial prefrontal activity reflect an effector-independent cortical dysfunction in conversion paresis which gradually disappears in parallel with clinical remission of paresis. The results link the medial prefrontal and dorsal premotor areas to the generation of intentional actions. We hypothesise that an excessive ‘veto’ signal generated in medial prefrontal cortex along with decreased premotor activity might constitute the functional substrate of conversion disorder. This notion warrants further examination in a larger group of affected patients.
•We mapped finger-tapping activity in a patient recovering from conversion paresis.•Activity of dorsal premotor cortex gradually emerged during repeated fMRI sessions.•Conversely, medial prefrontal activity tapered off with recovery from paresis.•The pattern was also expressed during finger-tapping with the non-affected hand.•It may represent a substrate of cortical dysfunction in conversion disorder.
Journal Article
Neural correlates of conversion disorder: overview and meta-analysis of neuroimaging studies on motor conversion disorder
by
Liegl, Gregor
,
Pieh, Christoph
,
Boeckle, Markus
in
Brain - diagnostic imaging
,
Brain - physiopathology
,
Care and treatment
2016
Background
Conversion 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).
Methods
A 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.
Results
Patients 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.
Conclusions
Neuronal 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.
Journal Article
Modification of both functional neurological symptoms and neuroimaging patterns with a good anatomoclinical concordance: a case report
by
Magnin, Eloi
,
Moulin, Thierry
,
Aybek, Selma
in
Brain
,
Brain - diagnostic imaging
,
Brain - physiopathology
2019
Background
In the nineteenth century, Jean Martin Charcot explained functional neurological disorder (formerly called conversion disorder) as a “psychodynamic” lesion. Numerous advances in neuroimaging have permitted identification of the neural underpinnings of this disorder.
Case presentation
Herein we describe a case of functional neurological disorder (FND) with initial left sensorimotor deficit, in-coordinated limb movements, neglect, clouded consciousness, slurred speech and a semiology of visual impairment. A single photon emission computed tomography (SPECT) showed a right thalamic hypoperfusion, which is rather concordant with the initial semiology. Later, the semiology changed, presenting with a predominantly neurovisual complex presentation. The second SPECT showed no more thalamic abnormalities but an hypoperfusion in the right temporo-occipital junction, right inferior parietal lobe and left superior frontal lobe, which is also rather concordant with the changing semiology.
Conclusions
This case illustrates the evolving neuroimaging patterns of FND but also the concordance between semiology and neuroimaging findings in FND supporting Charcot's theory of “dynamic lesion”.
Journal Article
Pituitary volumes are changed in patients with conversion disorder
by
Yildirim, Hanefi
,
Baykara, Sema
,
Mermi, Osman
in
Adult
,
Analysis of covariance
,
Biomedical and Life Sciences
2016
Our study group previously measured pituitary volumes and found a relationship between somatoform disoders and pituitary volumes. Therefore, in conversion disorder, another somatoform disorder, we hypothesized that pituitary gland volumes would be reduced. Twenty female patients and healthy controls were recruited to the present investigation. The volumes of the pituitary gland were determined by using a 1.5 Tesla magnetic resonance scanner. We found that the pituitary gland volumes of the patients with conversion disorder were significantly smaller than those of healthy control subjects. In the patients with conversion disorder but not in the healthy control group, a significant negative correlation between the duration of illness and pituitary gland volume was determined. In summary, in the present study, we suggest that the patients with conversion disorder have smaller pituitary volumes compared to those of healthy control subjects. Further studies should confirm our data and ascertain whether volumetric alterations determined in the patients with conversion disorder can be changed with treatment or if they change over time.
Journal Article
Myelopathy: chameleons and mimics
2017
The diagnosis of spinal cord disease may be delayed or missed if the presentation does not conform to the expected pattern of a symmetrical spastic paraparesis with sphincter dysfunction and a sensory level. This may occur when a myelopathy has yet to evolve fully, or is highly asymmetrical, as in Brown-Séquard syndrome. Other potential distractions include fluctuating symptoms, as may accompany spinal cord demyelination, and pseudoneuropathic features, as seen acutely in spinal shock and in the chronic setting with some high cervical cord lesions. A second pathology, such as a polyneuropathy or polyradiculopathy, can mask the presence of a myelopathy. The converse situation, of non-myelopathic disease mimicking a cord lesion, arises typically when symptoms and/or signs approximate bilateral symmetry. This may happen with certain diseases of the brain, or of the peripheral nerves, with functional disorders and even occasionally with non-neurological disease. These sources of diagnostic difficulty assume clinical importance when they delay the recognition of conditions that require urgent treatment.
Journal Article
Imaging hypnotic paralysis: implications for conversion hysteria
by
Halligan, Peter W
,
Athwal, Bal S
,
Oakley, David A
in
Adult
,
Biological and medical sciences
,
Brain
2000
In a single case study with positron emission tomography (PET) functional imaging, hypnotic paralysis activated similar brain areas to those in conversion hysteria, supporting the view that hypnosis and hysteria might share common neurophysiological mechanisms.
Journal Article
Globus sensation: findings on videofluoroscopic examinations
by
Laufer, Igor
,
Weinstein, Gregory S
,
Levine, Marc S
in
Adenoids - diagnostic imaging
,
Adult
,
Aged
2003
To determine the findings on videofluoroscopy of the pharynx and esophagus in patients with a globus sensation and compare them with a similar group of patients with dysphagia.
A computerized search of radiology files revealed 83 patients with a globus sensation who had videofluoroscopic examinations of the pharynx and esophagus during a 10-year period from 1989-1999. A computerized search was also performed to generate an age- and sex-matched group of 83 patients with dysphagia who also had videofluoroscopic examinations during this period. Original radiologic reports were reviewed to determine the frequency of morphologic and functional abnormalities of the pharynx and esophagus in these 2 groups.
Early closure of the cricopharyngeus was found in 13 (16%) patients with globus versus 2 (2%) with dysphagia (p < 0.01). Enlarged pharyngeal tonsils were found in 31 (37%) patients with globus versus 17 (21%) with dysphagia (p < 0.05). Enlarged lingual tonsils were characterized on barium studies by nodularity or lobulation of the posterior-inferior base of the tongue and valleculae in all patients, and the palatine tonsils were symmetrically enlarged in all but 2 patients. No other radiographic findings were significantly associated with a globus sensation.
Early closure of the cricopharyngeus and enlarged lingual or palatine tonsils may contribute to the development of a globus sensation, but the pathophysiologic basis for this association remains unclear.
Journal Article