Multitask fMRI and machine learning approach improve prediction of differential brain activity pattern in patients with insomnia disorder.

We investigated the differential spatial covariance pattern of blood oxygen level-dependent (BOLD) responses to single-task and multitask functional magnetic resonance imaging (fMRI) between patients with psychophysiological insomnia (PI) and healthy controls (HCs), and evaluated features generated by principal component analysis (PCA) for discrimination of PI from HC, compared to features generated from BOLD responses to single-task fMRI using machine learning methods. In 19 patients with PI and 21 HCs, the mean beta value for each region of interest (ROIbval) was calculated with three contrast images (i.e., sleep-related picture, sleep-related sound, and Stroop stimuli). We performed discrimination analysis and compared with features generated from BOLD responses to single-task fMRI. We applied support vector machine analysis with a least absolute shrinkage and selection operator to evaluate five performance metrics: accuracy, recall, precision, specificity, and F2. Principal component features showed the best classification performance in all aspects of metrics compared to BOLD response to single-task fMRI. Bilateral inferior frontal gyrus (orbital), right calcarine cortex, right lingual gyrus, left inferior occipital gyrus, and left inferior temporal gyrus were identified as the most salient areas by feature selection. Our approach showed better performance in discriminating patients with PI from HCs, compared to single-task fMRI.

Psychogenic Nonepileptic Seizures in Patients With Epilepsy: A Comparative Study With Patients With Pure Epilepsy.

ABSTRACT: Psychogenic nonepileptic seizures (PNES) represent management challenges, especially if associated with epilepsy. We aimed to evaluate patients with mixed epilepsy (true and PNES) and compare them with pure epilepsy to identify predictors of psychogenic seizures. This study included 40 patients with pure epilepsy and 40 patients with mixed epilepsy matched in age and sex. Patients underwent neurological assessment, semistructured psychiatric clinical interview, and video electroencephalogram monitoring. We found that unemployment, divorce, and seizure frequency were higher in mixed epilepsy, as well as history of family dysfunction, child adversity, and depressive and dissociative disorders. Both groups were similar regarding family history for seizures and personality dysfunction scores. Family dysfunction, child adversity, and depressive disorders were predictors of PNES. We recommend early evaluation for social instability, family dysfunction, child adversity, and depressive disorders in epileptic patients with higher seizure frequency to avoid misdiagnosis of false drug-resistant epilepsy and enhance proper management.

Psychogenic non-epileptic seizures in children - psychophysiology & dissociative characteristics.

The purpose of this study was to determine psychophysiology and dissociative characteristics of psychogenic non-epileptic seizures (PNES) in a clinical pediatric setting. A retrospective chart review was conducted over a 5-year period that included children meeting criteria for probable, clinically established or documented PNES. Of these, 33 patients (81%) underwent psychophysiology assessment as part of standardized care and were selected for study inclusion. Ages ranged from 10 to 17 years inclusive (70% female). The majority of patients were found to have some form of autonomic decompensation at baseline (82%) and lack of autonomic recovery from a cognitive stressor (58%). Inhibition of electrodermal skin response to laboratory stressor was associated with significantly longer duration of PNES illness (t=2.65, p=.013), while elevated heart rate (above 90th percentile) was associated with significantly higher frequency of PNES events in the month preceding diagnosis (t=3.1, p=.004). High levels of dissociation and hyperventilation symptoms were self-reported by adolescent patients (n=19) with a moderate degree of positive association (r=0.35, p=.038). The majority of patients (n= 25, 89%) were taught to correct respiratory CO2 levels during a single biofeedback training session. Conclusions: Child PNES populations appear to be characterized by chronic autonomic hyperarousal reflecting severity of their symptoms, which can feasibly be targeted for behavioral treatment.

Care providers' views on burden of psychosomatic symptoms of IS-traumatized female refugees participating in a Humanitarian Admission Program in Germany: A qualitative analysis.

BACKGROUND: Traumatized refugees often suffer from diverse psychosomatic symptoms. Female Yazidi refugees from Northern Iraq who survived attacks of the so-called "Islamic State" were brought to Germany to receive special medical and psychotherapeutic treatment in a unique worldwide humanitarian admission program (HAP). Here, we report on their psychosomatic symptoms and helpful strategies from the perspective of care providers. METHODS: Care providers (N = 84) in this HAP were interviewed in an individual setting as well as in focus groups to gather information about the HAP beneficiaries' psychosomatic symptoms. Data analysis followed Qualitative Content Analysis by Mayring. RESULTS: The care providers reported five main psychological burdens of the Yazidis: 1) insecurity regarding loss, 2) worries about family members, 3) ambivalence about staying in Germany or returning to Iraq, 4) life between two worlds and 5) re-actualization of the traumatic experiences. The predominant psychological symptoms the care providers noticed were fear, depressive symptoms, feelings of guilt, and sleep and eating disorders. Regarding somatic symptoms, the care providers mainly received complaints about pain in the head, back, chest and stomach. Helpful strategies for providing adequate health care were care providers' cooperating with physicians, precise documentation of beneficiaries' symptoms, and additional support in directing the beneficiaries through the health care system. Regarding psychotherapy, interpreters help to overcome language barriers, onsite psychotherapy, flexible therapy appointments, psychoeducational methods, time for stabilization, and support in coping with daily life aspects. In the care providers' experience, psychotherapists have to build a relationship of trust. After grief therapy, a trauma-specific therapy in a culturally adapted way is possible. CONCLUSION: The HAP is a unique model health care program to offer highly traumatized refugees medical and psychological help. Care providers reported on several (psycho-)somatic symptoms of the traumatized women. The strategies the HAP care providers perceived as helpful can be recommended for similar projects in the future.

Role of Yoga and Meditation as Complimentary Therapeutic Regime for Stress-Related Neuropsychiatric Disorders: Utilization of Brain Waves Activity as Novel Tool.

During recent decades, stress-related neuropsychiatric disorders such as anxiety, depression, chronic tension headache, and migraine have established their stronghold in the lives of a vast number of people worldwide. In order to address this global phenomenon, intensive studies have been carried out leading to the advancement of drugs like anti-depressants, anxiolytics, and analgesics which although help in combating the symptoms of such disorders but also create long-term side effects. Thus, as an alternative to such clinical practices, various complementary therapies such as yoga and meditation have been proved to be effective in alleviating the causes and symptoms of different neuropsychiatric disorders. The role of altered brain waves in this context has been recognized and needs to be pursued at the highest level. Thus, the current study provides a review focused on describing the effects of yoga and meditation on anxiety and depression as well as exploring brain waves as a tool for assessing the potential of these complementary therapies for such disorders.

[A consideration of the effects of aging on psychosomatic symptoms in the elderly].

In elderly patients with so-called psychogenic physical symptoms, changes with age of the symptoms were discussed from the standpoint of geriatric psychiatry. In recent years, the diagnostic criteria for psychogenic physical symptoms have been revised and are closer to the definition of psychosomatic disorders. In aging, the aging phenomenon of each body organ progresses, and the brain is no exception. Clinical findings suggest that conventional physical and mental symptoms are alleviated as brain function declines in general. If dementia is added, the speed of relief will increase. In Japan, where super-aging is advancing, the need to focus on the positive aspects of aging is discussed.

The management of adult patients with severe chronic small intestinal dysmotility.

Adult patients with severe chronic small intestinal dysmotility are not uncommon and can be difficult to manage. This guideline gives an outline of how to make the diagnosis. It discusses factors which contribute to or cause a picture of severe chronic intestinal dysmotility (eg, obstruction, functional gastrointestinal disorders, drugs, psychosocial issues and malnutrition). It gives management guidelines for patients with an enteric myopathy or neuropathy including the use of enteral and parenteral nutrition.

Atypical duration of epileptic and psychogenic nonepileptic events.

OBJECTIVES: We aimed to estimate the frequency of epileptic seizures (ES) and psychogenic nonepileptic seizures (PNES) with atypical duration in our epilepsy monitoring unit (EMU), in order to raise awareness of atypical durations of both types of events. MATERIALS & METHODS: We retrospectively reviewed all consecutive video-electroencephalogram (vEEG) recordings in our medical center's EMU from January 2013 to December 2017 and identified patients with seizures with atypical duration. Short PNES were defined as those lasting fewer than 2 min and long ES as those lasting for more than 5 min. RESULTS: The files of 830 adult (age >16 years) patients were reviewed, of whom 26 patients (3.1%, mean age: 33.3 ±â€¯9.8 years, 12 females) were diagnosed as having an unusual seizure duration. Among 432 patients with ES during monitoring, fourteen patients [3.2% (95% confidence interval (CI): 1.5%-5.0%), mean age: 33.0 ±â€¯12.2, 5 females [had long ES durations (exceeding 5 min). In 64% of patients with long ES, the events were provoked by antiepileptic drug (AED) withdrawal during vEEG, 62% had focal lesion on brain imaging, and 64% had a frontotemporal or a temporal seizure focus. Among 223 patients diagnosed with PNES, 12 patients [5.4% (95% CI: 2.2%-8.6%), mean age: 33.6 ±â€¯6.6, 7 females] had short PNES durations (less than 2 min) and demonstrated motor (9/12, 75%), altered responsiveness (6/12, 50%), and vocalization (5/12, 42%) as the most prominent clinical features. CONCLUSIONS: The data from our case files highlight two main considerations in the diagnosis of paroxysmal events: prolonged event can be due to ES, while short events can be psychogenic.

Clinical characteristics of functional (psychogenic nonepileptic) seizures: An international retrospective study.

PURPOSE: We conducted a multicenter international cross-cultural comparative study to investigate clinical semiology and predisposing factors of functional seizures in a large cohort of patients living in different countries around the world. We hypothesized that semiology and predisposing factors of functional seizures differ between various world regions. METHODS: We conducted this retrospective observational study in adults with functional seizures admitted to epilepsy centers in Iran, Qatar, USA, France, Georgia, Egypt, and United Arab Emirates (UAE). We assessed and compared the demographic and clinical seizure characteristics of these patients, according to the patients' reports and review of the ictal recordings during video-electroencephalogram (EEG) monitoring. RESULTS: Five hundred nine patients were included (270 from Iran, 74 from Qatar, 63 from France, 43 from the USA, 22 from Egypt, 20 from UAE, and 17 from Georgia). Although all major manifestations of functional seizures (e.g., aura, loss of responsiveness, generalized motor seizures, ictal injury) were seen in all world regions, seizure semiology differed significantly across countries. Auras, ictal urinary incontinence, and ictal injury were more commonly reported by the American patients than patients from other world regions, whereas loss of responsiveness and generalized motor seizures were more frequently observed in the Iranian and American patients than the European and Arab patients. CONCLUSION: Semiology of functional seizures seems to vary across various regions of the world; socioeconomic, cultural, ethnic, and religious differences may play an essential role in the modulation of functional seizures semiology across different nations and cultures.

Differentiating psychogenic nonepileptic from epileptic seizures: A mixed-methods, content analysis study.

BACKGROUND: Identification of clinical features that might distinguish psychogenic nonepileptic seizures (PNES) from epileptic seizures (ES) is of value for diagnosis, management, and understanding of both conditions. Previous studies have shown that patients' descriptions of their seizures reflect differences in content and delivery. We aimed to compare verbal descriptions of PNES and ES using a mixed-methods approach. METHODS: We analyzed data from semi-structured interviews in which patients with video-electroencephalography (EEG)-confirmed ES (n = 30) or PNES (n = 10) described their seizures. Two masked raters independently coded the transcripts for relevant psychological categories and discrepancies that were noted and resolved. Additional analyses were conducted using the Linguistic Inquiry and Word Count system. The identified phenomena were descriptively compared, and inferential analyses assessed group differences in frequencies. A logistic regression analysis examined the predictive power of the most distinctive phenomena for diagnosis. RESULTS: As compared with ES, PNES reported longer seizures, more preseizure negative emotions (e.g., fear), anxiety symptoms (e.g., arousal, hyperventilation), altered vision/olfaction, and automatic behaviors. During seizures, PNES reported more fear, altered breathing, and dissociative phenomena (depersonalization, impaired time perception). Epileptic seizures reported more self-injurious behavior. Postseizure, PNES reported more fear and weeping and ES more amnesia and aches. The predictive power when including these variables was 97.5%. None of the single predictor variables was significant. The few but consistent linguistic differences related to the use of some pronouns and references to family. CONCLUSIONS: Although no single clinical feature definitively distinguishes PNES from ES, several features may be suggestive of a PNES diagnosis, including longer duration, negative emotion (i.e., fear) throughout the events, preseizure anxiety, ictal dissociation, and postseizure weeping. Fewer reports of ictal self-injury and postseizure amnesia and aches may also indicate the possibility of PNES.

Nonepileptic attack disorder and functional movement disorder: A clinical continuum?

Nonepileptic attack disorder (NEAD) and functional movement disorder (FMD) are functional neurological disorders commonly seen in neuropsychiatry services. Although their initial referral pathways involve epileptologists (NEAD) and specialists in movement disorders (FMD), these conditions are currently classified as two possible manifestations of a single underlying conversion disorder. We set out to compare the characteristics of patients with NEAD and patients with FMD in order to quantify the degree of overlap between these patient groups. We retrospectively reviewed comprehensive clinical data from 146 consecutive patients with functional neurological disorders (NEAD: n = 117; FMD: n = 29) attending a specialist Neuropsychiatry Clinic run by a single Consultant in Behavioral Neurology. The two clinical groups were directly compared with regard to demographic and clinical characteristics, as well as somatic and psychiatric presentations. The results showed that in most features, there were no significant differences between patients with NEAD and patients with FMD. However, patients with NEAD reported an earlier age at onset (p = 0.033) and a higher proportion of acute onset (p = 0.037), alterations of consciousness (p = 0.001), and headache (p = 0.042), whereas patients with FMD reported a higher prevalence of childhood abuse (p = 0.008), as well as mobility problems (p = 0.007) and comorbid functional symptoms (dysarthria, p = 0.004; dizziness, p = 0.035; weakness, p = 0.049). Despite different phenotypic presentations, NEAD and FMD might represent a clinical continuum, with relevant implications in terms of both diagnostic strategies and treatment approaches.

Distinct associations of DSM-5 Somatic Symptom Disorder, the Diagnostic Criteria for Psychosomatic Research-Revised (DCPR-R) and symptom severity in patients with irritable bowel syndrome.

OBJECTIVE: The clinical management of high symptom severity is a challenging task with patients with functional somatic disorders. We investigated the extent to which DCPR-revised (DCPR-R) syndromes and the DSM-5 category of Somatic Symptom Disorder (SSD) were able to predict symptom severity in 203 consecutive tertiary care patients with irritable bowel syndrome (IBS). METHOD: Semistructured interview were used for assessing DCPR-R and validated scales for SSD (combining PHQ-12 and WI-7), severity of symptoms (IBS-SSS), psychological distress (HADS), and psychosocial functioning (SF-12). RESULTS: Compared to moderate severity (IBS-SSS = 175-300), patients in the high range of severity (IBS-SSS > 300) had significantly more DCPR-R syndromes (particularly alexithymia and persistent somatization), higher psychological distress, and poorer psychosocial functioning, but showed no difference for SSD. DCPR-R, particularly alexithymia and persistent somatization, significantly and independently predicted IBS severity by explaining 18.5% of the IBS-SSS variance with large effect size (d = 1.18), after controlling for covariables. Conversely, SSD was not able to significantly predict IBS severity. CONCLUSIONS: This study highlights the need of an integrative approach in the medical setting. Psychosomatic factors play a relevant role in the individual perception of symptom severity and should be carefully evaluated for clinical management of functional syndromes.

Management of functional neurological disorder.

Functional neurological disorder (FND) is a common cause of persistent and disabling neurological symptoms. These symptoms are varied and include abnormal control of movement, episodes of altered awareness resembling epileptic seizures and abnormal sensation and are often comorbid with chronic pain, fatigue and cognitive symptoms. There is increasing evidence for the role of neurologists in both the assessment and management of FND. The aim of this review is to discuss strategies for the management of FND by focusing on the diagnostic discussion and general principles, as well as specific treatment strategies for various FND symptoms, highlighting the role of the neurologist and proposing a structure for an interdisciplinary FND service.

The coexistence of psychogenic nonepileptic and epileptic seizures in the same patient is more frequent than expected: Is there any clinical feature for defining these patients?

OBJECTIVES: This study aimed to investigate the prevalence of psychogenic nonepileptic seizures (PNES) and PNES-epilepsy coexistence within all video-electroencephalography (EEG) monitoring unit (VEMU) referrals and to identify semiological and electrophysiological features to differentiate patients with PNES-epilepsy coexistence from PNES-only. METHODS: We retrospectively reviewed medical files, VEMU reports, and videos of 1983 adult patients. Demographical, historical, clinical, neuroimaging, and electrophysiological parameters of all patients were recorded. We classified patients into five groups as definite PNES-only, definite PNES-epilepsy coexistence, definite PNES-probable epilepsy coexistence, probable PNES-definite epilepsy coexistence, and probable PNES-only. We defined a "definite" group when we saw the ictal EEG and/or video recording of the seizure. The "probable" term is used when there is strong evidence from the history of a particular seizure type and suggestive interictal EEGs without video recordings. RESULTS: Two hundred and three of 1983 patients (10.23%) had PNES. Sixty-six of patients with PNES (32.51%) had definite PNES-epilepsy coexistence. When probable cases were included, the PNES-epilepsy coexistence ratio was 53.69% within all patients with PNES. The prevalence of PNES-epilepsy coexistence was 3.32% within all our VEMU referrals. Lower high school graduation rate, earlier age of disease onset, history of status epilepticus, febrile convulsion and brain surgery, use of three or more antiepileptic drugs, and abnormal magnetic resonance imaging (MRI) findings supported PNES-epilepsy coexistence (p < 0.05). On the contrary, seizure duration longer than 10 min was in favor of PNES-only (p < 0.05). CONCLUSIONS: The prevalence of PNES-epilepsy coexistence might be more frequent in VEMUs than expected. Some demographic and semiological features and electrophysiological findings might be useful in differentiating patients with PNES-epilepsy coexistence from patients with PNES-only.

Emergency room diagnoses of psychogenic nonepileptic seizures with psychogenic status and functional (psychogenic) symptoms: Whopping.

Collecting 130 electronic medical records and diagnoses from emergency room stays of eleven patients with confirmed psychogenic nonepileptic seizure (PNES) over a 17-year period (2001-2018), 48 different diagnostic terms were retrieved. This emphasized the need for a consensual terminology encompassing not only PNES but also all functional transient (paroxysmal) events, including episodes of motor or sensory deficits, and cognitive symptoms. Rather than defining what it is not (PNES, stroke mimicks…), it would be more accurate to define what it is: a paroxysmal functional event.

Impaired Action Control in Patients With Functional Movement Disorders.

OBJECTIVE: Despite being a major cause of neurological disability, the neural mechanisms of functional movement disorders (FMDs) remain poorly understood. Recent studies suggest that FMD is linked to dysfunctional motor and prefrontal regions that could lead to motor and cognitive impairments. The aim of this study was to investigate different components of action control in FMD by using choice-reaction, stop-signal, and Simon tasks. METHODS: Thirty patients with an FMD were prospectively recruited from the University of Louisville Movement Disorders Clinic and compared with 53 healthy control subjects, recruited from the Vanderbilt University Medical Center Movement Disorders Clinic. FMD motor symptom severity was rated with the Simplified Functional Movement Disorder Rating Scale (S-FMDRS). By using a computer and handheld response grips, participants completed three action-control tasks (choice-reaction task, stop-signal task, and Simon task) that tested action initiation, action cancelation, and interference control over actions. Action-control measures were compared between groups with analyses of variance. RESULTS: Patients with FMD were less proficient in suppressing incorrect response impulses on the Simon task and were slower to stop on the stop-signal task compared with healthy control subjects. No significant correlation with neuropsychological measurements, S-FMDRS scores, and action-control measurements was observed. CONCLUSIONS: These results suggest that two forms of inhibitory control, selective impulse inhibition and global action cancelation, are impaired in patients with FMD, independent of slowing on go reaction times. Improved understanding of action control in FMD may help in the development of new diagnostic and therapeutic strategies.

Internal Versus External Frame of Reference in Functional Movement Disorders.

OBJECTIVE: The purpose of this study was to determine whether patients with functional movement disorders (FMDs) differ in their internal versus external locus of control (LOC) and whether LOC in these patients affected disease severity, quality of life, and functional impairment compared with control subjects with degenerative (Parkinson's disease) and nondegenerative (focal dystonia) neurological conditions. METHODS: A total of 156 patients with FMD (N=45), Parkinson's disease (N=64), and focal dystonia (N=47) were recruited between June 2015 and August 2017. The authors administered the general Levenson Multidimensional LOC (LOC-G) and health-specific Multidimensional Health LOC (LOC-H) scales. An internal LOC was represented similarly in both scales: the external LOC included "chance" and "powerful others" in the LOC-G measure and chance, "other people," and "doctors" in the LOC-H measure. Quality of life, functional impairment, and FMD severity were assessed. One-way analysis of variance and adjusted logistic regressions were used, as well as ordinary least-squares between and within groups, respectively. RESULTS: Patients with FMD had lower external chance LOC-G scores compared with patients in the Parkinson's disease group (odds ratio=0.90, p=0.03) and higher internal (odds ratio=1.22, p=0.01) and lower external (odds ratio=0.77, p=0.02) doctors LOC-H scores compared with patients in the focal dystonia group. External powerful others LOC-G score was associated with functional impairment (regression coefficient=-0.04, p=0.02). There were no effects of LOC on quality of life or disease severity. CONCLUSIONS: Patients with FMD exhibited high "within our control" internal general and health-specific frame of reference. LOC had no influence on quality of life or disease severity in this patient population.

Functional Stroke Symptoms: A Narrative Review and Conceptual Model.

Stroke services have been reconfigured in recent years to facilitate early intervention. Throughout stroke settings, some patients present with functional symptoms that cannot be attributed to a structural cause. Emphasis on fast diagnosis and treatment means that a proportion of patients entering the care pathway present with functional symptoms that mimic stroke or have functional symptoms in addition to vascular stroke. There is limited understanding of mechanisms underlying functional stroke symptoms, how the treatment of such patients should be managed, and no referral pathway or treatment. Predisposing factors vary between individuals, and symptoms are heterogeneous: onset can be acute or insidious, and duration can be short-lived or chronic in the context of new or recurrent illness cognitions and behaviors. This article proposes a conceptual model of functional symptoms identified in stroke services and some hypotheses based on a narrative review of the functional neurological disorder literature. Predisposing factors may include illness experiences, stressors, and chronic autonomic nervous system arousal. Following the onset of distressing symptoms, perpetuating factors may include implicit cognitive processes, classical and operant conditioning, illness beliefs, and behavioral responses, which could form the basis of treatment targets. The proposed model will inform the development of theory-based interventions as well as a functional stroke care pathway.

Emotional Reactivity as a Vulnerability for Psychogenic Nonepileptic Seizures? Responses While Reliving Specific Emotions.

OBJECTIVE: Dysfunction in emotional processes is a hypothesized contributor to functional neurological disorders (FNDs), yet few studies have evoked real-time emotion during multimethod assessment incorporating subjective, behavioral, and psychophysiological indicators. This approach may reveal clinical and neurobiological vulnerability to FND and clarify how dysfunctional emotional processes serve as perpetuating factors. METHODS: Eleven participants with video-EEG-confirmed diagnoses of psychogenic nonepileptic seizures (PNES) were compared with 49 seizure-free trauma control subjects (TCs) with or without clinically elevated posttraumatic stress symptoms (25 clinically elevated [TC-clin], 24 not clinically elevated [TC-nonclin]). Participants recalled and described memories evoking anger, shame, happiness, and neutral feelings. RESULTS: Even though PNES patients and TCs reported similar amounts of emotional experience, PNES patients reported more difficulty reliving emotions and were less likely to complete the relived shame task. During and after reliving happiness, PNES and TC-clin groups showed respiratory sinus arrhythmia (RSA) decreases, indicating parasympathetic withdrawal, whereas the TC-nonclin group showed RSA increases. CONCLUSIONS: Findings from this pilot study are consistent with previous research and clinical observations that emotional engagement may be more effortful for PNES patients. Patterns of RSA change, which may also point to greater effortful engagement, were similar in PNES and TC-clin groups, suggesting that traumatic stress reactions may play a part. At the same time, experience of greater difficulty or avoidance may be even greater among PNES patients. Especially when regulatory resources are already limited, accumulated effort, coupled with self-threatening contexts such as shame, may be particularly problematic for those with PNES and perhaps other FNDs.

What Does Neuroscience Tell Us About the Conversion Model of Functional Neurological Disorders?

A dualistic mind-body understanding of functional neurological disorders (FNDs), also known as conversion disorders, has led to the view that the cause of the symptom should be either psychological (psychogenic) or physical (neurogenic-"organic"). One of the most influential psychological approaches is the Freudian model of conversion, which suggests that FNDs arise from a defense process in which emotional stress is converted into physical symptoms. This conversion theory has been challenged in recent years, accompanied by a shift in emphasis toward neuropathophysiological models of FND and away from historical psychological concepts. In this review, the authors consider the contemporary relevance of the conversion model from the neuroscientific perspective to reconcile the role of both psychological and biological factors in FND. A narrative review of recent neuroscientific findings pertaining to the conversion model of FND, encompassing neuroimaging, cognitive psychology, biological markers, and epigenetic studies, was performed. Research on the role of psychological stressors is discussed. Neurobiological mechanisms of repression of traumatic memories and their translation into physical symptoms are then explored. Finally, the role of physical symptoms as a potential protective defense mechanism against social stressors is considered. The authors argue that the conversion concept is consistent with recent neuroscientific research findings, and the model allows psychological and neurobiological concepts to be reconciled within a single account of FND that begins to resolve the dualistic mind-body dichotomy.