Persistent postural-perceptual dizziness: a useful new syndrome

Brain Mechanisms Explaining Postural Imbalance in Traumatic Brain Injury: A Systematic Review

Introduction: Persisting imbalance and falls in community-dwelling traumatic brain injury (TBI) survivors are linked to reduced long-term survival. However, a detailed understanding of the impact of TBI upon the brain mechanisms mediating imbalance is lacking. To understand the state of the art concerning the brain mechanisms mediating imbalance in TBI, we performed a systematic review of the literature. Methods: PubMed, Web of Science, and Scopus were searched and peer-reviewed research articles in humans, with any severity of TBI (mild, moderate, severe, or concussion), which linked a postural balance assessment (objective or subjective) with brain imaging (through computed tomography, T1-weighted imaging, functional magnetic resonance imaging [fMRI], resting-state fMRI, diffusion tensor imaging, magnetic resonance spectroscopy, single-photon emission computed tomography, electroencephalography, magnetoencephalography, near-infrared spectroscopy, and evoked potentials) were included. Out of 1940 articles, 60 were retrieved and screened, and 25 articles fulfilling inclusion criteria were included. Results: The most consistent finding was the link between imbalance and the cerebellum; however, the regions within the cerebellum were inconsistent. Discussion: The lack of consistent findings could reflect that imbalance in TBI is due to a widespread brain network dysfunction, as opposed to focal cortical damage. The inconsistency in the reported findings may also be attributed to heterogeneity of methodology, including data analytical techniques, small sample sizes, and choice of control groups. Future studies should include a detailed clinical phenotyping of vestibular function in TBI patients to account for the confounding effect of peripheral vestibular disorders on imbalance and brain imaging.

Optimizing vestibular neuritis management with modular strategies

Objective

This study proposes a "modular management" approach for vestibular neuritis (VN) to reduce chronicization and improve patient prognosis. The approach involves multi-factor grading and hierarchical intervention and was found to be more effective than traditional treatment strategies.

Methods

This retrospective analysis compared two groups of VN patients from two medical institutions. The intervention group of 52 patients received "modular management," while the control group of 51 patients did not receive this kind of management. Analyzed the early treatment strategies, 6-month prognosis, and other indicators of the two groups of patients, compared and analyzed their overall prognosis, and identified the risk factors affecting the chronicization.

Results

The modular management group had lower dizziness severity, better balance, lower anxiety, and higher video head impulse testing (v-HIT) gain after 6 months of onset. Analysis of factors related to persistent postural-perceptual dizziness (PPPD) in patients with VN showed positive correlations between the time from onset to diagnosis and PPPD, and Vertigo Symptom Scale (VSS), Dizziness Handicap Inventory (DHI), anxiety, and depression. Normalized vestibular rehabilitation was negatively correlated with PPPD, while gender, age, and early steroid use had no significant correlation. The multi-factor logistic regression model correctly classified 93.20% of the study subjects with a sensitivity of 87.50% and specificity of 94.90%.

Conclusion

The proposed "modular management" scheme for VN is a comprehensive and dynamic approach that includes health education, assessment, rehabilitation, therapy, evaluation, and prevention. It can significantly improve patient prognosis and reduce chronicization by shifting from simple acute treatment to continuous management.

Functional Gait Disorders: Clinical presentations, Phenotypes and Implications for treatment

BACKGROUND

Functional Gait Disorders (FGD) are a common presentation of motor-Functional Neurological Disorders (motor-FND) that affect walking ability.

AIM

To provide a narrative review of the current literature on FGD.

METHODS

A narrative overview of published literature was undertaken, based on a systematic search of relevant databases, authoritative texts and citation tracking.

RESULTS

FGD is multidimensional and disabling, with numerous phenotypes described in the literature, including 'knee buckling,' 'astasia-abasia' and 'excessive slowness.' Motor symptoms such as weakness or tremor, and non-motor symptoms, such as pain and fatigue may contribute to the disability and distress in FGD. Phenotypic features and clinical signs are seen in FGD that demonstrate inconsistency and incongruity with structural disease. A limited number of treatment studies have specifically focussed on FGD, however, reporting of outcomes from motor-FND cohorts has demonstrated short and long-term improvements in walking ability through multidisciplinary rehabilitation.

CONCLUSIONS

The relative contribution of motor and non-motor symptoms in FGD remains unknown, but it is likely that non-motor symptoms increase the illness burden and should be considered during assessment and treatment. Recommended treatment for FGD involves multidisciplinary rehabilitation, but optimum treatment elements are yet to be determined.

The Bárány Society position on 'Cervical Dizziness'

This paper describes the Bárány Society Classification OverSight Committee (COSC) position on Cervical Dizziness, sometimes referred to as Cervical Vertigo. This involved an initial review by a group of experts across a broad range of fields, and then subsequent review by the Bárány Society COSC. Based upon the so far published literature, the Bárány Society COSC takes the view that the evidence supporting a mechanistic link between an illusory sensation of self-motion (i.e. vertigo - spinning or otherwise) and neck pathology and/or symptoms of neck pain - either by affecting the cervical vertebrae, soft tissue structures or cervical nerve roots - is lacking. When a combined head and neck movement triggers an illusory sensation of spinning, there is either an underlying common vestibular condition such as migraine or BPPV or less commonly a central vestibular condition including, when acute in onset, dangerous conditions (e.g. a dissection of the vertebral artery with posterior circulation stroke and, exceedingly rarely, a vertebral artery compression syndrome). The Committee notes, that migraine, including vestibular migraine, is by far, the commonest cause for the combination of neck pain and vestibular symptoms. The committee also notes that since head movement aggravates symptoms in almost any vestibular condition, the common finding of increased neck muscle tension in vestibular patients, may be linked as both cause and effect, to reduced head movements. Additionally, there are theoretical mechanisms, which have not been explored, whereby cervical pain may promote vaso-vagal, cardio-inhibitory reflexes and hence by presyncopal mechanisms, elicit   transient   disorientation and/or imbalance. The committee accepts that further research is required to answer the question as to whether those rare cases in which neck muscle spasm is associated with a vague sense of spatial disorientation and/or imbalance, is indeed linked to impaired neck proprioception. Future studies should ideally be placebo controlled and double-blinded where possible, with strict inclusion and exclusion criteria that aim for high specificity at the cost of sensitivity. To facilitate further studies in "cervical dizziness/vertigo", we provide a narrative view of the important confounds investigators should consider when designing controlled mechanistic and therapeutic studies. Hence, currently, the Bárány COSC refrains from proposing any preliminary diagnostic criteria for clinical use outside a research study. This position may change as new research evidence is provided.

Potential risk factors of persistent postural-perceptual dizziness: a pilot study

BACKGROUND

Persistent postural-perceptual dizziness (PPPD) unifies the main characteristics of chronic subjective dizziness, visual vertigo and related diseases, which is a common chronic disease in neurology. At present, the pathology of PPPD is not fully understood.

OBJECTIVE

In this single-center retrospective case series review, we aim to investigate the potential risk factors of PPPD.

METHODS

Eighty inpatients diagnosed with PPPD were recruited with 81 apparently healthy controls. Patient-specific clinico-radiological data were collected from both groups. Conditions of hypertension, diabetes, smoking, and drinking were derived from medical history. Blood test results were recorded including total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, fibrinogen, vitamin B12, folic acid, total cholesterol, triglyceride, and folate level. The subjects were examined by carotid artery CTA and cranial MRI, and the imaging findings of carotid atherosclerosis (CAS), white matter hyperintensities (WMHs) and lacunar infarction (LI) were recorded. Binary logistic regression analysis was used to investigate the difference between the case and control groups. Significance was defined as p value less than 0.05.

RESULTS

The prevalence rate of hypertension in the case group was significantly higher than that in the control group, and the detection rates of CAS, WMHs, and LI in the case group were significantly higher than those in the control group (p < 0.05 for all).

CONCLUSION

Hypertension, CAS, WMHs, and LI are associated with PPPD, which may be potential risk factors for its development.

Vestibular paroxysmia: Clinical features and imaging findings; a literature review

According to the definition of neurovascular compression syndromes (NVCS), a vascular structure in direct contact with a cranial nerve is causing mechanical irritation of the neural tissue producing correlating symptoms. Vestibular paroxysmia is an example of a neurovascular compression which is caused by neurovascular contact between the eighth cranial nerve and a vessel. It is crucial to understand the unique anatomy of the vestibulocochlear nerve in order to study the syndrome which is the result of its compression. More specifically, the long transitional zone between central and peripheral myelin plays a central role in clinical significance, as the transitional zone is the structure most prone to mechanical injury. Imaging techniques of the eighth cranial nerve and the surrounding structures are substantial for the demonstration of clinically significant cases and potential surgical decompression. The goal of the current review is to present and study the existing literature on vestibular paroxysmia and to search for the most appropriate imaging technique for the syndrome. An extensive literature search of PubMed database was performed, and the studies were ranked based on evidence-based criteria, followed by descriptive statistics of the data. The present analysis indicates that 3D CISS MRI sequence is superior to any other sequence, in the most studies reviewed, regarding the imaging of neurovascular compression of the eighth cranial nerve.

Effect of vestibular exercise and optokinetic stimulation using virtual reality in persistent postural-perceptual dizziness

To determine the effect of customized vestibular exercise (VE) and optokinetic stimulation (OS) using a virtual reality system in patients with persistent postural-perceptual dizziness (PPPD). Patients diagnosed with PPPD were randomly assigned to the VE group or VE with OS group. All participants received VE for 20 min using a virtual reality system with a head mount display once a week for 4 weeks. The patients in the VE with OS group additionally received OS for 9 min. We analysed the questionnaires, timed up-to-go (TUG) test, and posturography scores at baseline and after 4 weeks. A total of 28 patients (median age = 74.5, IQR 66–78, men = 12) completed the intervention. From baseline to 4 weeks, the dizziness handicap inventory, activities of daily living (ADL), visual vertigo analogue scale, and TUG improved in the VE group, but only ADL and TUG improved in the VE with OS group. Patients with severe visual vertigo improved more on their symptoms than patients with lesser visual vertigo (Pearson’s p = 0.716, p < 0.001). Our VE program can improve dizziness, quality of life, and gait function in PPPD; however, additional optokinetic stimuli should be applied for individuals with visual vertigo symptoms.

Characteristics of persistent postural perceptual dizziness patients in a multidisciplinary dizziness clinic

BACKGROUND

Persistent Postural Perceptual Dizziness (PPPD) is a newly defined condition which was added to the International Classification of Vestibular Disorders in 2017. Little is known about its impact on patients.

OBJECTIVE

The goal of this study was to analyze the symptomology, epidemiology and impact of PPPD on patients.

METHODS

A retrospective chart review was done to identify patients who attended the Multidisciplinary Dizziness Clinic (MDC) and were diagnosed with PPPD. Responses to demographic questions, health-related quality of life surveys and several well-validated questionnaires commonly used to assess dizziness severity were analyzed.

RESULTS

One hundred patients were diagnosed with PPPD between March 2017 and January 2019, of which 80%(80/100) were females. The average Dizziness Handicap Index score was 60.3±19.0. Responses to the Patient Health Questionnaire classified 53 patients (53/99;53.5%) as moderately to severely depressed. Sixty-four patients (64/100;64.0%) were minimally or mildly anxious according to the Generalized Anxiety Disorder scale. The average Vertigo Symptom Scale score was 24.1/60. The average Situational Vertigo Questionnaire score was 2.00. Forty-nine (49/100;49.0%) patients had migraine symptoms according to the Migraine Screen Questionnaire.

CONCLUSIONS

In conclusion, patients with PPPD display important handicap and an elevated risk of depression, anxiety and migraines.

Visual Perception in Migraine: A Narrative Review

Migraine, the most frequent neurological ailment, affects visual processing during and between attacks. Most visual disturbances associated with migraine can be explained by increased neural hyperexcitability, as suggested by clinical, physiological and neuroimaging evidence. Here, we review how simple (e.g., patterns, color) visual functions can be affected in patients with migraine, describe the different complex manifestations of the so-called Alice in Wonderland Syndrome, and discuss how visual stimuli can trigger migraine attacks. We also reinforce the importance of a thorough, proactive examination of visual function in people with migraine.

Migraine Features in Patients with Persistent Postural-Perceptual Dizziness

OBJECTIVES

To evaluate the presence of migraine features in patients with persistent postural-perceptual dizziness (PPPD).

METHODS

In a retrospective survey study, consecutive patients presenting to a tertiary care neurotology clinic during an 18-month period were given questionnaires about headache and dizziness symptoms. The survey responses plus history and examination of the patient were used to diagnose patients with PPPD. The prevalence of migraine headache, vestibular migraine (VM), and migraine characteristics was evaluated.

RESULTS

In total, 36 subjects with PPPD were included in the study. The mean age of the subjects was 56 ± 16 years with a female (72%) predominance. A total of 19 (53%) patients met the International Classification of Headache Disorders criteria for migraine headache, and 6 of those (17%) met the criteria for definite VM. Of the patients who did not meet full migraine headache criteria, 6 (17%) patients met 4 of 5 criteria, and 5 (14%) patients met 3 of 5 criteria. There was no significant difference between PPPD patients who fulfilled full migraine headache criteria and those who did not in sensitivity to light, sound, smells, weather changes, feelings of mental fog/confusion, and sinus pain/facial pressure.

CONCLUSIONS

This study demonstrates that a majority of patients with PPPD fulfill the criteria for migraine headache. A large proportion of PPPD patients who do not meet the full criteria for migraine headache still meet a majority of the migraine headache criteria. This suggests an association between the 2 conditions. PPPD may be a part of the spectrum of otologic migraine, where migraine manifests as otologic symptoms.

People with persistent postural-perceptual dizziness demonstrate altered postural strategies in complex visual and cognitive environments

BACKGROUND

People with PPPD report imbalance, increase in symptoms and impaired function within complex visual environments, but understanding of the mechanism for these behaviors is still lacking.

OBJECTIVE

To investigate postural control in PPPD we compared changes in center of pressure (COP) and head kinematics of people with PPPD (N = 22) and healthy controls (N = 20) in response to different combinations of visual and cognitive perturbations during a challenging balance task.

METHODS

Participants stood in a tandem position. Static or moving stars (0.2 Hz, 5 mm or 32 mm amplitude, anterior-posterior direction) were displayed through a head-mounted display (HTC Vive). On half the trials, participants performed a serial-3 subtraction task. We measured medio-lateral and anterior-posterior path and acceleration of COP and head.

RESULTS

Controls significantly increased all COP and head parameters with the cognitive task whereas PPPD increased only COP ML path and acceleration. Only controls significantly increased head anterior-posterior & medio-lateral acceleration with moving visual load. Cognitive task performance was similar between groups.

CONCLUSIONS

We observed altered postural strategies in people with PPPD, in the form of reduced movement with challenge, particularly around the head segment. The potential of this simple and portable head-mounted display setup for differential diagnosis of vestibular disorders should be further explored.

Multimodal treatment of persistent postural-perceptual dizziness

BACKGROUND

Persistent postural-perceptual dizziness (PPPD) is a chronic disorder with fluctuating symptoms of dizziness, unsteadiness, or vertigo for at least three months. Its pathophysiological mechanisms give theoretical support for the use of multimodal treatment. However, there are different therapeutic programs and principles available, and their clinical effectiveness remains elusive.

METHODS

A database of patients who participated in a day care multimodal treatment program was analyzed regarding the therapeutic effects on PPPD. Vertigo Severity Scale (VSS) and Hospital Anxiety and Depression Scale (HADS) were assessed before and 6 months after therapy.

RESULTS

Of a total of 657 patients treated with a tertiary care multimodal treatment program, 46.4% met the criteria for PPPD. PPPD patients were younger than patients with somatic diagnoses and complained more distress due to dizziness. 63.6% completed the follow-up questionnaire. All patients showed significant changes in VSS and HADS anxiety, but the PPPD patients generally showed a tendency to improve more than the patients with somatic diagnoses. The change in the autonomic-anxiety subscore of VSS only reached statistical significance when comparing PPPD with somatic diagnoses (p = .002).

CONCLUSIONS

Therapeutic principles comprise cognitive-behavioral therapy, vestibular rehabilitation exercises, and serotonergic medication. However, large-scale, randomized, controlled trials are still missing. Follow-up observations after multimodal interdisciplinary therapy reveal an improvement in symptoms in most patients with chronic dizziness. The study was not designed to detect diagnosis-specific effects, but patients with PPPD and patients with other vestibular disorders benefit from multimodal therapies.

A review on the alterations in the brain of persistent postural-perceptual dizziness patients and non-pharmacological interventions for its management

Persistent postural perceptual dizziness (PPPD) is a relatively newer term, and this term is included in the International Classification of Diseases in its 11th revision. The typical features of PPPD include the presence of persistent dizziness, non-spinning vertigo, and unsteadiness, and these symptoms are exacerbated during upright posture, movement, or visual stimuli. Moreover, the structural changes have also been identified in the brains of PPPD patients, particularly in visual, vestibular, and limbic areas. These include a decrease in the volume and gyration of gray matter, a decrease in the blood flow to the cortex region, and alterations in the structural and functional connectivity, particularly in the visual-vestibular networks. Moreover, the impairment in sensory processing is restricted not only to the vestibular and visual regions; instead, there is a generalized impairment in the sensory processing, and thus, there is a multisensory dimension of sensory impairment. Selective serotonin uptake inhibitors and serotonin-norepinephrine reuptake inhibitors are the mainstay drugs for the management of PPPD patients. However, a significant proportion of PPPD patients do not show improvement in response to standard drug therapy. The employment of alternative and complementary treatment strategies, including vestibular rehabilitation therapy, cognitive behavioral therapy, and non-invasive vagal nerve stimulation, is effective in the management of PPPD patients. The present review discusses the alterations in the brains of PPPD patients along with the possible non-pharmacological treatment options in these types of patients.

Functional Head Impulse Test With and Without Optokinetic Stimulation in Subjects With Persistent Postural Perceptual Dizziness (PPPD): Preliminary Report

OBJECTIVE

Persistent postural perceptual dizziness (PPPD) is a clinical condition characterized by unsteadiness present on most days for a period of at least 3 months. The aim of our work was to assess vestibular function, the role of anxiety, and possible interactions between visual and vestibular systems in patients with PPPD.

STUDY DESIGN

Cross-sectional prospective study.

SETTING

Tertiary referral center.

PATIENTS

Twenty-five PPPD patients.

INTERVENTIONS

Clinical history was collected before examination; vestibular function was assessed through bedside examination, video and functional head impulse test (video-HIT, f-HIT). The latter test was based on having the patient identify an optotype displayed on a computer screen during passive head rotations. The test was repeated while optokinetic stimulation (OKS) was given on the screen. Results were compared with those of 25 controls. State and trait anxiety levels were measured with the State-Trait Anxiety Inventory (STAI) questionnaire. Anxiety before and after vestibular examination was assessed using a VAS scale.

MAIN OUTCOME MEASURE

Results of video and functional HIT with and without OKS.

RESULTS

Video-HIT and f-HIT showed normal values in all subjects. f-HIT with OKS provoked more reading errors in patients than in controls. The interaction of group per time detected different decreasing trends between the two groups (p = 0.0002).Patients presented a reduction in anxiety levels after examination. Nine patients fulfilled diagnostic criteria for vestibular migraine, eight of whom presented nystagmus either to positional tests or vibration test. Only anxiety levels before testing were predictive of worsening of f-HIT with optokinetic stimulation (p = 0.0007).

CONCLUSIONS

Our data support the hypothesis that increased anxiety may play a role in visuo-vestibular interactions; moreover, they are not inconsistent with the hypothesis that OKS might provoke a "threatening effect," leading to gaze bias during examination.

Persistent Postural-Perceptual Dizziness-A Systematic Review of the Literature for the Balance Specialist

OBJECTIVE

To present a systematic review of the current data on persistent postural-perceptual dizziness (PPPD), a useful and relatively new diagnosis for a disorder that has previously been known by many different names. In addition, to discuss diagnostic criteria and management strategies for this condition with the otologist in mind.

DATA SOURCES

CINAHL, Embase, PubMed, Medline, PsycINFO, PubMed, Google Scholar.

REVIEW METHOD

The phrase "persistent postural-perceptual dizziness" and its acronym "PPPD" were used.

RESULTS

From 318 articles, 15 were selected for full analysis with respect to PPPD. Most were case-control studies, with one consensus paper from the Bárány Society available. Overall, the pathophysiology of PPPD remains relatively poorly understood, but is likely to be a maladaptive state to a variety of insults, including vestibular dysfunction and not a structural or psychiatric one. Cognitive behavioral therapy, vestibular rehabilitation, selective serotonin uptake inhibitors (SSRIs), and serotonin-norepinephrine reuptake inhibitors (SNRIs) all seem to have a role in its management.

CONCLUSIONS

PPPD is useful as a diagnosis for those treating dizziness as it helps to define a conglomeration of symptoms that can seem otherwise vague and allows for more structured management plans in those suffering from it.

Working-age adults' perspectives on living with persistent postural-perceptual dizziness: a qualitative exploratory study

OBJECTIVES

To (a) explore the experiences of persistent postural-perceptual dizziness (PPPD), formerly chronic subjective dizziness on the personal, work and social lives of working-age adults; (b) enhance current understandings of the condition and its impact on the lives of working-age adults and (c) highlight points for consideration and importance to clinical practice.

METHODS

This qualitative exploratory study drew on interpretive descriptive methodology. Working-age adults (n=8) diagnosed with PPPD were recruited from a single New Zealand community-based specialist clinic. Data from interviews (n=8) and postinterview reflections (n=2) were analysed using thematic analysis.

RESULTS

Three themes were constructed: (1) It sounds like I'm crazy-referring to the lack of medical, social and self-validation associated with PPPD; (2) I'm a shadow of my former self-representing the impact of the condition on sense of self and life trajectory and (3) How will I survive?- highlighting individual coping processes.

CONCLUSION

This study contributed to the existing body of knowledge by highlighting the complexity and fluidity of experiencing PPPD. It also drew attention to the tension between the acute illness framework that forms the basis of many therapeutic interactions and the enduring psychosocial support needs of the person experiencing PPPD. The findings highlighted that contextual factors need to be taken into account and that a person-centred and biopsychosocial approach, rather than a condition-specific biomedical approach, is needed for care to be perceived as meaningful and satisfactory.

Postural control during galvanic vestibular stimulation in patients with persistent perceptual-postural dizziness

Over the past years galvanic vestibular stimulation (GVS) has been increasingly applied to stimulate the vestibular system in health and disease, but not in patients with persistent postural-perceptual dizziness (PPPD) yet. We functionally tested motion perception thresholds and postural responses to imperceptible noisy (nGVS) and perceptible bimastoidal GVS intensities in patients with PPPD with normal vestibulo-ocular reflexes. We hypothesized that GVS destabilizes PPPD patients under simple postural conditions stronger compared to healthy controls. They were compared to healthy subjects under several conditions each with the eyes open and closed: baseline with firm platform support, standing on foam and cognitive demand (count backward). Low and high GVS intensities (range 0.8-2.8 mA) were applied according to the individual thresholds and compared with no GVS. PPPD patients showed a reduced perception threshold to GVS compared to healthy control subjects. Median postural sway speed increased with stimulus intensity and on eye closure, but there was no group difference, irrespective of the experimental condition. Romberg's ratio was consistently lower during nGVS than in all other conditions. Group-related dissociable effects were found with the eyes closed in (i) the baseline condition in which high GVS elicited higher postural sway of PPPD patients and (ii) in the foam condition, with better postural stability of PPPD patients during perceptible GVS. Group and condition differences of postural control were neither related to anxiety nor depression scores. GVS may be helpful to identify thresholds of vestibular perception and to modulate vestibulo-spinal reflexes in PPPD, with dissociable effects with respect to perceptible and imperceptible stimuli. The sway increase in the baseline of PPPD may be related to an earlier transition from open- to closed-loop mode of postural control. In contrast, the smaller sway of PPPD in the foam condition under visual deprivation is in line with the known balance improvement under more demanding postural challenges in PPPD. It is associated with a prolonged transition from open- to closed-loop postural feedback control. It could also reflect a shift of intersensory weighting with a smaller dependence on proprioceptive feedback control in PPPD patients under complex tasks. In summary, GVS discloses differences between simple and complex balance tasks in PPPD.

Brain responses to virtual reality visual motion stimulation are affected by neurotic personality traits in patients with persistent postural-perceptual dizziness

OBJECTIVE

Persistent postural perceptual dizziness (PPPD) is a common vestibular disorder of persistent dizziness and unsteadiness, exacerbated by upright posture, self-motion, and exposure to complex or moving visual stimuli. Previous functional magnetic resonance imaging (fMRI) studies found dysfunctional activity in the visual-vestibular cortices in patients with PPPD. Clinical studies showed that the anxiety-related personality traits of neuroticism and introversion may predispose individuals to PPPD. However, the effects of these traits on brain function in patients with PPPD versus healthy controls (HCs) have not been studied.

METHODS

To investigate potential differential effects of neuroticism and introversion on functioning of their visuo-vestibular networks, 15 patients with PPPD and 15 HCs matched for demographics and motion sickness susceptibility underwent fMRI during virtual reality simulation of a rollercoaster ride in vertical and horizontal directions.

RESULTS

Neuroticism positively correlated with activity in the inferior frontal gyrus (IFg), and enhanced connectivity between the IFg and occipital regions in patients with PPPD relative to HCs during vertical versus horizontal motion comparison.

CONCLUSIONS

In patients with PPPD, neuroticism increased the activity and connectivity of neural networks that mediate attention to visual motion cues during vertical motion. This mechanism may mediate visual control of balance in neurotic patients with PPPD.