Effects of electrical stimulation in vestibular cortex areas in humans.

The case of a patient with focal epilepsy is reported who underwent presurgical evaluation by stereotactic intracranial electroencephalographic (EEG) recording. A subdural semi-grid electrode, consisting of three multi-channel strip electrodes, was implanted over the temporal lobe and temporo-occipital region; one multi-channel depth electrode was applied towards the posterior insular cortex. During electrical stimulation and EEG monitoring eye movements were recorded by 3-D video-oculography. Stimulation of the medial temporal gyrus induced blurring of vision and horizontal nystagmus. Stimulation of the superior temporal gyrus with low intensities also induced blurring of vision and a simi…

Who is at risk for ongoing dizziness and psychological strain after a vestibular disorder?

Patients with vestibular vertigo syndromes often suffer from anxiety and depression, whereas patients with psychiatric disorders often experience subjective unsteadiness, dizziness, or vertigo. Thus, it has been hypothesized that the vestibular system may be interlinked with the emotion processing systems. The aim of the current study was to evaluate this hypothesis by correlating vestibular and psychiatric symptoms with the course of the disease over 1 year. This interdisciplinary, prospective, longitudinal study included a total of 68 patients with acute vestibular vertigo syndromes. Four subgroups of patients with benign paroxysmal positioning vertigo (BPPV, n=19), acute vestibular neuri…

Vestibular dysfunction in major depression

Insular strokes cause no vestibular deficits.

Background and Purpose— In previous imaging studies, the posterior insular cortex (IC) was identified as an essential part for vestibular otolith perception and considered as a core region of a human vestibular cortical network. However, it is still unknown whether lesions exclusively restricted to the posterior IC suffice to provoke signs of vestibular otolith dysfunction. Thus, present data aimed to test whether patients with lesions restricted to the IC showed vestibular otolith dysfunction. Methods— We studied 10 acute unilateral stroke patients with lesions restricted to the IC which were tested for signs of vestibular otolith dysfunction, such as tilts of subjective visual vertical, …

Standfest? Erste Ergebnisse der Entwicklung eines kognitiv-verhaltenstherapeutischen Gruppenschulungsprogramms zur Behandlung des somatoformen Schwindels

Anhand einer explorativen Fragestellung soll der Einfluss eines Schulungsprogramms fur somatoforme Schwindelpatienten auf dysfunktionale Krankheitsreprasentationen, Symptomstarke und psychische Komorbiditat uberpruft werden. Randomisiertes Wartekontrollgruppen-Design: 10 Patienten wurden der Kontrollgruppe zugewiesen; 14 Patienten der Interventionsgruppe durchliefen die Diagnostik im Pratest, Posttest und eine 3- bzw. 12-Monats-Katamnese. Die Fragebogenbatterie umfasste den Illness Perception Questionnaire, Vertigo Symptom Scale, Vertigo Handicap Questionnaire, Hospital Anxiety and Depression Scale und Physical Health Questionnaire. Hypothesenkonform verbesserte sich die personliche Kontrol…

Persistence of symptoms in primary somatoform vertigo and dizziness: a disorder "lost" in health care?

The aim of this study was to perform a 3-year follow-up of primary somatoform vertigo and dizziness (SVD) regarding health care use and treatment. Ninety-two patients with dizziness underwent detailed vestibular neurophysiological testing and a Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. Psychometric assessments comprised the Vertigo Symptom Scale, the Vertigo Handicap Questionnaire, the SCL-90-R, and the Short-Form-36 Health Survey. At the 3-year follow-up, 65 patients with primary SVD (anxiety, n = 29; depression, n = 14; somatoform disorders, n = 22) were reassessed (70.7% response). The patients improved in symptom severity (p…

Evidence for cortical visual substitution of chronic bilateral vestibular failure (an fMRI study).

Bilateral vestibular failure (BVF) is a rare disorder of the labyrinth or the eighth cranial nerve which has various aetiologies. BVF patients suffer from unsteadiness of gait combined with blurred vision due to oscillopsia. Functional MRI (fMRI) in healthy subjects has shown that stimulation of the visual system induces an activation of the visual cortex and ocular motor areas bilaterally as well as simultaneous deactivations of multisensory vestibular cortex areas. Our question was whether the chronic absence of bilateral vestibular input (BVF) causes a plastic cortical reorganization of the above-described visual-vestibular interaction. We used fMRI to measure the differential effects of…

Why Do Subjective Vertigo and Dizziness Persist over One Year after a Vestibular Vertigo Syndrome?

The overlap and interlinkage of dizzy symptoms in patients with psychiatric and vestibular vertigo/dizziness disorders is the subject of an ongoing debate. In a one-year follow up in 68 patients with vestibular vertigo syndromes, the persistency of vertigo and dizziness symptoms was examined and correlated with vestibular parameters and results from a psychiatric evaluation. Patients with vestibular migraine showed poorest improvement of vertigo and dizziness symptoms over time. In addition, patients who developed anxiety or depressive disorder after the onset of the vestibular disorder showed poor improvement and high persistency of symptoms.

Posterior insular cortex - a site of vestibular-somatosensory interaction?

Background In previous imaging studies the insular cortex (IC) has been identified as an essential part of the processing of a wide spectrum of perception and sensorimotor integration. Yet, there are no systematic lesion studies in a sufficient number of patients examining whether processing of vestibular and the interaction of somatosensory and vestibular signals take place in the IC. Methods We investigated acute stroke patients with lesions affecting the IC in order to fill this gap. In detail, we explored signs of a vestibular tone imbalance such as the deviation of the subjective visual vertical (SVV). We applied voxel-lesion behaviour mapping analysis in 27 patients with acute unilate…

Interaction of somatoform and vestibular disorders

The high coincidence of organic vestibular and somatoform vertigo syndromes has appeared to support pathogenic models showing a strong linkage between them. It was hypothesised that a persisting vestibular dysfunction causes the development of anxiety disorders.To determine the relation between vestibular deficits and somatoform vertigo disorders in an interdisciplinary prospective study.Participants were divided into eight diagnostic groups: healthy volunteers (n=26) and patients with benign paroxysmal positioning vertigo (BPPV, n=11), vestibular neuritis (n=11), Menière's disease (n=7), vestibular migraine (n=15), anxiety (n=23), depression (n=12), or somatoform disorders (n=22). Neuro-ot…

Improved Postural Control after Behavioural Short Term Intervention in Patients with Psychiatric Dizziness

Background:Patients with psychiatric dizziness often report subjective instability of stance and gait and fear of falls. They showed increased activity of their body sway in static posturography compared to normals (1, 2). Aim of the present study was to evaluate the efficiency of a behavioural therapy by static posturography.Methods:14 patients with psychiatric dizziness were included in the prospective study on static posturography to quantify the postural sway (sway path) during upright stance under different conditions. the psychosomatic examination comprised of standardized interviews (SCID-Interview) and a psychometric examination battery (SCL-90, VSS, VHQ). Results of static posturog…

Deutschsprachige Validierung des Vertigo Handicap Questionnaire (VHQ) anhand einer Patientenstichprobe mit vestibulärem und somatoformem Schwindel

The Vertigo Handicap Questionnaire (VHQ) by Yardley (1992) assesses physical and psychosocial impairments of vertigo or dizziness. Our study examines the structure, reliability, and aspects of validity of the German version of the VHQ. 98 vestibular vertigo syndromes vs. 90 patients with somatoform vertigo and dizziness were evaluated with the VHQ, symptom severity (VSS), distress (GSI), anxiety and depression (HADS), catastrophizing beliefs (ACQ), fear of body sensations (BSQ), and quality of life (SF-36). For diagnostic classification detailed clinical neurological, neuro-otological and psychosomatic testing were conducted. Principal components analysis identified two factors, which could…

Different short-term modulation of cortical motor output to distal and proximal upper-limb muscles during painful sensory nerve stimulation

The pattern of upper-limb muscle activation following painful stimulation has not been clarified in detail. We investigated the short-term inhibitory and excitatory effects of painful electrical digital stimulation on the motoneuron pools of distal and proximal upper-limb muscles. Transcranial magnetic stimulation (TMS) was used as test stimulus, and painful digital nerve stimulation as conditioning stimulus for motor evoked potential (MEP) recordings over the abductor digiti minimi (ADM), abductor pollicis brevis (APB), biceps brachii (BB), and deltoid muscles. Inhibition of the conditioned MEP response was most prominent in the distal muscles, whereas BB and deltoid muscles were only weak…

P13. Compensation processes for central vestibular dysfunction in patients with acute medullary infarctions (FDG-PET study)

18F-fluorodeoxyglucose hypometabolism in cerebellar tonsil and flocculus in downbeat nystagmus.

A patient with downbeat nystagmus was examined by F-fluorodeoxyglucose-positron emission tomography once while off and twice while on successful treatment with 4-aminopyridine. All positron emission tomography scans of the patient showed a reduced cerebral glucose metabolism bilaterally in the region of the cerebellar tonsil and flocculus/paraflocculus when compared with a normal database of the whole brain. An additional region-of-interest analysis revealed that 4-aminopyridine treatment lessened the hypometabolism. This finding supports the hypothesis that the cerebellar tonsil and (para-) flocculus play a crucial role in downbeat nystagmus. The hypometabolism might reflect reduced inhibi…