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Objectives: Catch-up saccades help to compensate for loss of gaze stabilization during rapid head rotation in case of vestibular deficit. While overt saccades observed after head rotation are obviously visually guided, some of these catch-up saccades occur with shorter latency while the head is still moving, anticipating the needed final eye position. These covert saccades seem to be generated based on the integration of multisensory inputs. Vision could be one of these inputs, but the known delay for triggering visually guided saccades questions this possibility. The main objective of this study is to evaluate the potential role of visual information for controlling (triggering and guiding) the first catch-up saccades in patients suffering from bilateral vestibulopathy. To investigate this, we used head impulse test in a virtual reality setting allowing to create different visuo-vestibular mismatch conditions., Design: Twelve patients with bilateral vestibulopathy were recruited. We assessed in our patient group the validity of our virtual reality head impulse testing approach by comparing recorded eye and head movement to classical video head impulse test. Then, using the virtual reality system, we tested head impulse test under both normal and three visuo-vestibular mismatch conditions. In these mismatch conditions, the movement of the visual scene relative to the head movement was altered: decreased in amplitude by 50% (half), nullified (freeze), or inverted in direction (inverse). Recorded eye and head movements during these different conditions were then analyzed, more specifically the characteristics of the first catch-up saccade., Results: Impaired vestibulo-ocular reflex required subjects to systematically perform catch-up saccades, which could be covert or overt. The latency of the first catch-up saccade increased along with the amount of visuo-vestibular mismatch between the four conditions (i.e., from normal to half to freeze to inverse) and, consequently, the mean percentage of covert saccades decreased with increasing visual feedback error. However, the freeze and inverse conditions allowed us to reveal the existence of many saccades performed in the wrong direction relative to visual feedback. These visually discordant saccades were present in over half of the trials, they were mainly covert and their percentage was inversely correlated with residual vestibulo-ocular reflex gain., Conclusions: Visual information significantly impacts catch-up saccade latency and the relative number of covert saccades during head impulse testing in vestibular deficit. However, in more than 50% of trials involving a visuo-vestibular mismatch, catch-up saccades remained directed in the compensatory direction relative to head movement, that is, they were visually discordant. Therefore, contrary to previously published proposals, visual information does not appear to be the primary component of the multisensory inputs required for the production of catch-up covert saccades in vestibular deficit. Finally, we discuss a new nomenclature of catch-up saccades in case of vestibular deficit introducing the terms of open and closed loop saccades., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 The American Auditory Society.)

Antibodies against the neuronal protein Ma2 have been reported in a peculiar form of paraneoplastic encephalitis with prominent involvement of the limbic, brainstem, and diencephalic structures and usually associated with germ cell testicular, lung, or breast cancer. The diagnosis is frequently challenged by atypical clinical manifestations including parkinsonism, sleep disturbances, hypothalamic-pituitary dysfunctions, and motor neuron-like syndrome. In recent years, the advent of monoclonal antibodies targeting immune checkpoints has deeply changed the treatment of different tumors, especially melanoma and lung cancer. However, given their nature, an increasing number of neurological immune-related adverse events, including ocular motor abnormalities, have been described. Here, we report a woman with advanced non-small cell lung cancer treated with anti-PD-L1 durvalumab, presenting with an isolated pendular torsional nystagmus, in association with anti-Ma2 antibodies. This peculiar case widens our knowledge on the clinical presentation of anti-Ma2 encephalitis associated with checkpoint inhibitors., (© 2023. The Author(s).)

Background: Myasthenia gravis (MG) is an autoimmune disease that targets acetylcholine receptor (AChR) of the neuromuscular junction. New-onset MG after SARS-CoV-2 vaccination has rarely been reported., Case Presentation: We report about three patients who presented new-onset myasthenia gravis after receiving mRNA SARS-CoV-2 vaccination. The patients were all males and older than 55 years. All the patients presented with ocular and bulbar symptoms. The interval between vaccine administration and MG onset ranged from 3 days after the first dose to 10 days after the second dose. All the patients had elevated serum AChR antibodies and responded to pyridostigmine. Two out of three patients were successfully treated with IVIG or plasma exchange and with long-term immunosuppression., Conclusions: MG is a rare disease; clinicians should be aware of possible new-onset MG after SARS-CoV-2 vaccination, especially with the current recommendation of booster doses. The hyperstimulation of the innate immune system or the exacerbation of a subclinical pre-existing MG could be possible explanations., (© 2022. Fondazione Società Italiana di Neurologia.)

Study Objectives: To evaluate neurophysiological alterations of visual function in idiopathic REM sleep Behavior Disorder (iRBD) both as markers and predictors of neurodegenerative disorders., Methods: In a longitudinal follow-up study of 46 consecutive iRBD patients (follow-up duration 8.4 ± 3.4 years), the baseline parameters in luminance-contrast pattern (VEPp), red-green color (VEPc) and motion-onset (VEPm) Visual Evoked Potentials in iRBD were compared to early (ePD) and advanced (aPD) Parkinson's Disease subjects. Parameters of latency and amplitude of iRBD converters to neurodegenerative disease were compared with those of the non-converters., Results: The VEP P100 mean latency values for both eyes and for both stimulation checks (30' and 15') were significantly longer in all the three groups of patients as compared to controls; moreover latencies were longer in aPD than in the iRBD group who did not differ from the ePD group. The same held true when we analyzed the number of abnormal subjects belonging to each diagnostic group with a higher number of abnormal subjects in the aPD group compared to both the ePD and in iRBD groups. Chromatic and motion potentials were not different from controls and did not differ in the 3 diagnostic groups. The iRBD subjects who converted to a neurodegenerative disorder showed longer P100 latencies and a higher occurrence of VEPp abnormalities than those who did not convert. Again chromatic and motion VEPs were not different depending on conversion., Conclusions: In iRBD patients the detection of an abnormal VEPp should be considered as a red flag for possible synnucleinopathy, eventually contributing in stratifying the risk of phenoconversion., (Copyright © 2021 Elsevier B.V. All rights reserved.)

After extensive evaluation, one-third of patients affected by polyneuropathy remain undiagnosed and are labelled as having chronic idiopathic axonal polyneuropathy, which refers to a sensory or sensory-motor, axonal, slowly progressive neuropathy of unknown origin. Since a sensory neuropathy/neuronopathy is identified in all patients with genetically confirmed RFC1 cerebellar ataxia, neuropathy, vestibular areflexia syndrome, we speculated that RFC1 expansions could underlie a fraction of idiopathic sensory neuropathies also diagnosed as chronic idiopathic axonal polyneuropathy. We retrospectively identified 225 patients diagnosed with chronic idiopathic axonal polyneuropathy (125 sensory neuropathy, 100 sensory-motor neuropathy) from our general neuropathy clinics in Italy and the UK. All patients underwent full neurological evaluation and a blood sample was collected for RFC1 testing. Biallelic RFC1 expansions were identified in 43 patients (34%) with sensory neuropathy and in none with sensory-motor neuropathy. Forty-two per cent of RFC1-positive patients had isolated sensory neuropathy or sensory neuropathy with chronic cough, while vestibular and/or cerebellar involvement, often subclinical, were identified at examination in 58%. Although the sensory ganglia are the primary pathological target of the disease, the sensory impairment was typically worse distally and symmetric, while gait and limb ataxia were absent in two-thirds of the cases. Sensory amplitudes were either globally absent (26%) or reduced in a length-dependent (30%) or non-length dependent pattern (44%). A quarter of RFC1-positive patients had previously received an alternative diagnosis, including Sjögren's syndrome, sensory chronic inflammatory demyelinating polyneuropathy and paraneoplastic neuropathy, while three cases had been treated with immune therapies., (© The Author(s) (2021). Published by Oxford University Press on behalf of the Guarantors of Brain.)

Background: Vestibular migraine (VM) is a relatively recently acknowledged vestibular syndrome with a very relevant prevalence of about 10% among patients complaining of vertigo. The diagnostic criteria for VM have been recently published by the Bárány Society, and they are now included in the latest version of the International Classification of Headache Disorders, yet there is no instrumental test that supports the diagnosis of VM., Objective: In the hypothesis that the integration of different vestibular stimuli is functionally impaired in VM, we tested whether the combination of abrupt vestibular stimuli and full-field, moving visual stimuli would challenge vestibular migraine patients more than controls and other non-vestibular migraineurs., Methods: In three clinical centers, we compared the performance in the functional head impulse test (fHIT) without and with an optokinetic stimulus rotating in the frontal plane in a group of 44 controls (Ctrl), a group of 42 patients with migraine (not vestibular migraine, MnoV), a group of 39 patients with vestibular migraine (VM) and a group of 15 patients with vestibular neuritis (VN)., Results: The optokinetic stimulation reduced the percentage of correct answers (%CA) in all groups, and in about 33% of the patients with migraine, in as many as 87% of VM patients and 60% of VN patients, this reduction was larger than expected from controls' data., Conclusions: The comparison of the fHIT results without and with optokinetic stimulation unveils a functional vestibular impairment in VM that is not as large as the one detectable in VN, and that, in contrast with all the other patient groups, mainly impairs the capability to integrate different vestibular stimuli.

Ataxia, causing imbalance, dizziness and falls, is a leading cause of neurological disability. We have recently identified a biallelic intronic AAGGG repeat expansion in replication factor complex subunit 1 (RFC1) as the cause of cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS) and a major cause of late onset ataxia. Here we describe the full spectrum of the disease phenotype in our first 100 genetically confirmed carriers of biallelic repeat expansions in RFC1 and identify the sensory neuropathy as a common feature in all cases to date. All patients were Caucasian and half were sporadic. Patients typically reported progressive unsteadiness starting in the sixth decade. A dry spasmodic cough was also frequently associated and often preceded by decades the onset of walking difficulty. Sensory symptoms, oscillopsia, dysautonomia and dysarthria were also variably associated. The disease seems to follow a pattern of spatial progression from the early involvement of sensory neurons, to the later appearance of vestibular and cerebellar dysfunction. Half of the patients needed walking aids after 10 years of disease duration and a quarter were wheelchair dependent after 15 years. Overall, two-thirds of cases had full CANVAS. Sensory neuropathy was the only manifestation in 15 patients. Sixteen patients additionally showed cerebellar involvement, and six showed vestibular involvement. The disease is very likely to be underdiagnosed. Repeat expansion in RFC1 should be considered in all cases of sensory ataxic neuropathy, particularly, but not only, if cerebellar dysfunction, vestibular involvement and cough coexist., (© The Author(s) (2020). Published by Oxford University Press on behalf of the Guarantors of Brain.)

The functional head impulse test is a new test of vestibular function based on the ability to recognize the orientation of a Landolt C optotype that briefly appears on a computer screen during passive head impulses imposed by the examiner over a range of head accelerations. Here, we compare its results with those of the video head impulse test on a population of vestibular neuritis patients recorded acutely and after 3 months from symptoms onset. The preliminary results presented here show that while both tests are able to identify the affected labyrinth and to show a recovery of vestibular functionality at 3 months, the two tests are not redundant, but complementary.

Objective: Mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) may involve extrahippocampal areas of structural damage and dysfunction. The accuracy of medium-term spatial memory can be tested by memory-guided saccades (MGS) to evaluate a functional impairment of the parahippocampal cortex (PHC), while voxel-based morphometry (VBM) analysis can be used to detect a structural damage of the latter region., Methods: MGS with 3- and 30-s memorization delays were compared between 7 patients affected by right MTLE-HS (r-MTLE-HS), 6 patients affected by left MTLE-HS, and 13 healthy controls. The same subjects underwent brain MRI for a VBM analysis. Correlation analysis was performed between the results of VBM and MGS and with patients' clinical data., Results: Right MTLE-HS patients showed impaired accuracy of leftward MGS with a 30-s memorization delay; their gray-matter volume was reduced in the right hippocampus and inferior temporal gyrus, and bilaterally in the cerebellum. Left MTLE-HS patients had normal MGS accuracy; their gray-matter volume was reduced in the left hippocampus, in the right-inferior temporal gyrus and corpus callosus, and bilaterally in the insular cortex and in the cerebellum. The difference between right and left parahippocampal volumes correlated with MGS accuracy, while right and left hippocampal volumes did not. Hippocampal and parahippocampal volume did not correlate with clinical variables such as febrile seizures, age at disease onset, disease duration, and seizure frequency., Conclusion: MGS abnormalities suggested the functional involvement of the right PHC in patients with r-MTLE-HS, supporting a right lateralization of spatial memory control and showing a relation between functional impairment and degree of atrophy.

Neurophysiological measurements of the vestibular function for diagnosis and follow-up evaluations provide an objective assessment, which, unfortunately, does not necessarily correlate with the patients' self-feeling. The literature provides many questionnaires to assess the outcome of rehabilitation programs for disequilibrium, but only for the Dizziness Handicap Inventory (DHI) is an Italian translation available, validated on a small group of patients suffering from a peripheral acute vertigo. We translated and validated the reliability and validity of the DHI, the Situational Vertigo Questionnaire (SVQ), and the Activities-Specific Balance Confidence Scale (ABC) in 316 Italian patients complaining of dizziness due either to a peripheral or to a central vestibular deficit, or in whom vestibular signs were undetectable by means of instrumental testing or clinical evaluation. Cronbach's coefficient alpha, the homogeneity index, and test-retest reproducibility, confirmed reliability of the Italian version of the three questionnaires. Validity was confirmed by correlation test between questionnaire scores. Correlations with clinical variables suggested that they can be used as a complementary tool for the assessment of vestibular symptoms. In conclusion, the Italian versions of DHI, SVQ, and ABC are reliable and valid questionnaires for assessing the impact of dizziness on the quality of life of Italian patients with peripheral or central vestibular deficit.

The use of cerebellar repetitive transcranial magnetic stimulation has been attempted for perturbing reflexive and voluntary eye movements, but discrepancies are seen between the results of distinct studies possibly due to the different stimulation sites, intensities, and paradigms. We describe the after effects of 20 and 40 s continuous Theta Burst Stimulation (cTBS) as compared to sham stimulation, applied over the lateral cerebellar vermis and paravermis on Reflexive Saccades (RS) and Smooth Pursuit (SP) eye movements, recorded in the 30 min following stimulation. The experiments were carried out in eight healthy volunteers, and eye movements were recorded monocularly with video-oculography. The 40 s cTBS significantly increased the amplitude of ipsilateral RS and the acceleration of the ipsilateral SP, and this effect was detectable all over the 30-min recording period; 40 s cTBS did not modify the other parameters, namely the peak velocity, the duration and the latency of RS, and the latency and the velocity of SP. The 20 s cTBS was ineffective on all RS and SP parameters. Finally, we detected a significant quite-linear reduction of RS peak velocity over time, but this was independent from cTBS and was probably caused by fatigue. The effects of 40 s cTBS in our experiments mimic the disorder of ocular motility in Wallenberg's syndrome and could result from functional impairment of cerebellopontine pathways. This effect lasts 30 min at least, and can provide a useful framework for adaptive ocular motor studies.

In response to passive high-acceleration head impulses, patients with low vestibulo-ocular reflex (VOR) gains often produce covert (executed while the head is still moving) corrective saccades in the direction of deficient slow phases. Here we examined 23 patients using passive, and 9 also active, head impulses with acute (< 10 days from onset) unilateral vestibular neuritis and low VOR gains. We found that when corrective saccades are larger than 10°, the slow-phase component of the VOR is inhibited, even though inhibition increases further the time to reacquire the fixation target. We also found that 1 ) saccades are faster and more accurate if the residual VOR gain is higher, 2 ) saccades also compensate for the head displacement that occurs during the saccade, and 3 ) the amplitude-peak velocity relationship of the larger corrective saccades deviates from that of head-fixed saccades of the same size. We propose a mathematical model to account for these findings hypothesizing that covert saccades are driven by a desired gaze position signal based on a prediction of head displacement using vestibular and extravestibular signals, covert saccades are controlled by a gaze feedback loop, and the VOR command is modulated according to predicted saccade amplitude. A central and novel feature of the model is that the brain develops two separate estimates of head rotation, one for generating saccades while the head is moving and the other for generating slow phases. Furthermore, while the model was developed for gaze-stabilizing behavior during passively induced head impulses, it also simulates both active gaze-stabilizing and active gaze-shifting eye movements. NEW & NOTEWORTHY During active or passive head impulses while fixating stationary targets, low vestibulo-ocular gain subjects produce corrective saccades when the head is still moving. The mechanisms driving these covert saccades are poorly understood. We propose a mathematical model showing that the brain develops two separate estimates of head rotation: a lower level one, presumably in the vestibular nuclei, used to generate the slow-phase component of the response, and a higher level one, within a gaze feedback loop, used to drive corrective saccades., (Copyright © 2017 the American Physiological Society.)

Rigid ankle-foot orthoses (AFO) are commonly used for impeding foot drop during the swing phase of gait. They also reduce pain and improve gait kinematics in patients with weakness or loss of integrity of ankle-foot complex structures due to various pathological conditions. However, this comes at the price of constraining ankle joint mobility, which might affect propulsive force generation and balance control. The present study examined the effects of wearing an AFO on biomechanical variables and electromyographic activity of tibialis anterior (TA) and soleus muscles during gait initiation (GI). Nineteen healthy adults participated in the study. They initiated gait at a self-paced speed with no ankle constraint as well as wearing an AFO on the stance leg, or bilaterally. Constraining the stance leg ankle decreased TA activity ipsilaterally during the anticipatory postural adjustment (APA) of GI, and ipsilateral soleus activity during step execution. In the sagittal plane, the decrease in the stance leg TA activity reduced the backward displacement of the center of pressure (CoP) resulting in a reduction of the forward velocity of the center of mass (CoM) measured at foot contact (FC). In the frontal plane, wearing the AFO reduced the displacement of the CoP in the direction of the swing leg during the APA phase. The mediolateral velocity of the CoM increased during single-stance prompting a larger step width to recover balance. During step execution, the CoM vertical downward velocity is normally reduced in order to lessen the impact of the swing leg with the floor and facilitates the rise of the CoM that occurs during the subsequent double-support phase. The reduction in stance leg soleus activity caused by constraining the ankle weakened the vertical braking of the CoM during step execution. This caused the absolute instantaneous vertical velocity of the CoM at FC to be greater in the constrained conditions with respect to the control condition. From a rehabilitation perspective, passively- or actively-powered assistive AFOs could correct for the reduction in muscle activity and enhance balance control during GI of patients.

Background: The ocular vestibular myogenic potentials (oVEMP) can be elicited by monaural air-conducted sound stimulation, and are usually recorded from the contralateral eye. In clinical setting a binaural stimulation would save time and require less effort from the subjects., Objective: We evaluated the differences between monaural and binaural stimulation, and the possible effect of age and gender on oVEMP parameters., Methods: Air-conducted oVEMP were recorded by binaural and by monaural stimulation in a group of 54 normal subjects, aged from 12 to 83 years, and in 50 vestibular patients. From each side, we measured the latency of the N1 component, and the peak-to-peak N1-P1 amplitude. For both parameters we also computed the asymmetry ratio., Results: In normal subjects binaural stimulation produced slightly larger responses than monaural stimulation; detectability, latency and amplitude ratio were the same for the two techniques. We found no differences related to gender, and the age-induced amplitude decline was likely to be negligible.oVEMP recorded not in an acute phase of their disorder, proved to be abnormal in about 20% of the patients, and the normal or abnormal findings obtained either with monaural or with binaural stimulation were always concordant., Conclusions: The oVEMP obtained after binaural and monaural stimulation are very similar, and they are largely independent from age and gender.

The head impulse test (HIT) is nowadays recognized as the gold standard for clinical testing of the angular vestibulo-ocular reflex (VOR). By imposing unpredictable, abrupt head rotations in canal pairs' planes it aims at unveiling the dysfunction of the semicircular canal towards which the head is rotated based on Ewald's II law. Functional testing of the VOR aims at assessing the ability of the reflex to stabilize gaze in space and thus allow clear vision during head movements. The HIT device (HITD) approach exploits impulsive head rotations spawning a range of angular accelerations while requiring subjects to identify optotypes briefly displayed on a screen. Here we also recorded eye movements, so that the evaluation of the individual subject is based both on the VOR gain and on the percentage of correct answers with respect to a population of controls. Here we used the HITD to study 14 patients suffering from vestibular neuritis and 7 of those were re-tested after three months. We found that the HITD was able to unveil the ipsilesional deficit and the contralesional impairment, together with the improvement in the follow-up test.

Peripheral vestibular function may be tested quantitatively, by measuring the gain of the angular vestibulo-ocular reflex (aVOR), or functionally, by assessing how well the aVOR performs with respect to its goal of stabilizing gaze in space and thus allow to acquire visual information during the head movement. In recent years, several groups have developed clinical and quantitative approaches to functional testing of the vestibular system based on the ability to identify an optotype briefly displayed on screen during head rotations. Although the proposed techniques differ in terms of the parameters controlling the testing paradigm, no study has thus far dealt with understanding the role of such choices in determining the effectiveness and reliability of the testing approach. Moreover, recent work has shown that peripheral vestibular patients may produce corrective saccades during the head movement (covert saccades), yet the role of these eye movements toward reading ability during head rotations is not yet understood. Finally, no study has thus far dealt with measuring the true performance of their experimental setups, which is nonetheless likely to be crucial information for understanding the effectiveness of functional testing approaches. Thus we propose a new software and hardware research tool allowing the combined measurement of eye and head movements, together with the timing of the optotype on screen, during functional testing of the vestibulo-ocular reflex (VOR) based on the Head Impulse Test. The goal of such tool is therefore that of allowing functional testing of the VOR while collecting the experimental data necessary to understand, for instance, (a) the effectiveness of the covert saccades strategy toward image stabilization, (b) which experimental parameters are crucial for optimizing the diagnostic power of the functional testing approach, and (c) which conditions lead to a successful reading or an error trial.

We developed the head impulse testing device (HITD) based on an inertial sensing system allowing to investigate the functional performance of the rotational vestibulo-ocular reflex (VOR) by testing its gaze stabilization ability, independently from the subject's visual acuity, in response to head impulses at different head angular accelerations ranging from 2000 to 7000 deg/s(2). HITD was initially tested on 22 normal subjects, and a method to compare the results from a single subject (patient) with those from controls was set up. As a pilot study, we tested the HITD in 39 dizzy patients suffering, non-acutely, from different kinds of vestibular disorders. The results obtained with the HITD were comparable with those from the clinical head impulse test (HIT), but an higher number of abnormalities was detectable by HITD in the central vestibular disorders group. The HITD appears to be a promising tool for detecting abnormal VOR performance while providing information on the functional performance of the rotational VOR, and can provide a valuable assistance to the clinical evaluation of patients with vestibular disorders.

Continuous theta-burst stimulation (cTBS) applied over the cerebellum exerts long-lasting effects by modulating long-term synaptic plasticity, which is thought to be the basis of learning and behavioral adaptation. To investigate the impact of cTBS over the cerebellum on short-term sensory-motor memory, we recorded in two groups of eight healthy subject each the visually guided saccades (VGSs), the memory-guided saccades (MGSs), and the multiple memory-guided saccades (MMGSs), before and after cTBS (cTBS group) or simulated cTBS (control group). In the cTBS group, cTBS determined hypometria of contralateral centrifugal VGSs and worsened the accuracy of MMGS bilaterally. In the control group, no significant differences were found between the two recording sessions. These results indicate that cTBS over the cerebellum causes eye movement effects that last longer than the stimulus duration. The VGS contralateral hypometria suggested that we eventually inhibited the fastigial nucleus on the stimulated side. MMGSs in normal subjects have a better final accuracy with respect to MGSs. Such improvement is due to the availability in MMGSs of the efference copy of the initial reflexive saccade directed toward the same peripheral target, which provides a sensory-motor information that is memorized and then used to improve the accuracy of the subsequent volitional memory-guided saccade. Thus, we hypothesize that cTBS disrupted the capability of the cerebellum to make an internal representation of the memorized sensory-motor information to be used after a short interval for forward control of saccades.

Transcranial magnetic stimulation (TMS) transiently induces an electrical field in the tissues beneath the area of application, thereby perturbing local cortical activity if applied over the scalp. It can therefore be used to modulate cerebellar function in healthy humans. Even though the role of the cerebellum in eye movement control and adaptation is well known, few experiments have used eye movements to evaluate the effect of TMS over the cerebellum. Single-pulse TMS over the posterior vermis resulted in impaired accuracy of reflexive saccades, acceleration of smooth pursuit, and coordination of saccades and head movements. TMS over the cerebellar hemisphere decreased pursuit gain. Repetitive TMS (rTMS) over the posterior vermis impaired saccade adaptation in a double-step paradigm. Comparing the effects of TMS on different behavioural paradigms could be useful to test cerebellar control of reflexive and voluntary eye movements, and as a probe of cerebellar plasticity. rTMS appears to be especially interesting since its effects outlast the stimulation period and its behavioural consequences can therefore be measured without interfering with the execution of eye movements or with the experimental procedures.

Purpose: Neuroactive sex steroids influence neuron excitability, which is enhanced by estradiol (E2) and decreased by progesterone (Pg). In epilepsy, the production, metabolism, biologic availability, and activity of sex hormones may be affected by seizures themselves or by antiepileptic drugs (AEDs). This cross-sectional observational study was aimed at evaluating the relationships between sex steroids, seizure frequency, and other clinical parameters in women with partial epilepsy (PE) on AED treatments., Methods: Serum E2, Pg, sex hormone binding globulin (SHBG) levels, free E2 (fE2), and E2/Pg ratios were determined during the follicular and luteal phases in 72 adult women with PE, and in 30 healthy controls. Hormonal data were correlated with seizure frequency, age, body weight, body mass index (BMI), disease onset and duration, and AED therapies., Results: In patients, E2, fE2, and Pg levels were lower in both ovarian phases, whereas those of SHBG were higher than in controls. No significant changes in hormone levels and in prevalence of anovulatory cycles were observed between patients grouped according to their seizure frequency. However, when compared with those in healthy controls, luteal fE2 and Pg levels were chiefly impaired in women with more frequent seizures, mostly undergoing AED polytherapies, but not in those with absent or rarer seizures., Conclusions: The actual changes in sex steroid levels and E2/Pg ratios did not explain an increased seizure frequency in adult women with AED-treated PE, but patients with more severe disease showed more relevant changes in their sex hormone profile and impaired Pg levels during the luteal phase.

Sleep paralysis (SP) is a common parasomnia. The diagnostic criteria for SP, as reported in the International Classification of Sleep Disorders, are essentially clinical, as electroencephalography (EEG)-polysomnography (PSG) is not mandatory. We describe a subject whose sleep-related events fulfilled the diagnostic criteria for SP, even though her visual hallucinations were elementary, repetitive and stereotyped, thus differing from those usually reported by patients with SP. Video/EEG-PSG documented the focal epileptic nature of the SP-like episodes.

Memory-guided saccades (MGSs) with 3 s memorization delay were recorded in healthy subjects using four different paradigms: two "regular" MGS paradigms with the peripheral target lit for 0.2 s (MGS2) and for 1.8 s (MGS18); a multiple memory-guided saccade (MMGS) paradigm with the target lit for 1.8 s and the instruction to perform a visually guided saccade (VGS) towards it before the MGS; a trained memory-guided saccades (TMGSs) paradigm where the same target was presented so that the subjects should made 10 VGSs before the MGS. The longer target presentation interval (MGS18 paradigm) did not improve the accuracy of MGS. The execution of the VGSs improved the accuracy of the corrective saccades made after the first MGS to drive the eyes closer to the target, and this improvement was independent from the number of the VGSs (there was no difference between the MMGS and the TMGS paradigms). The VGSs provide a template that improves the capability of the corrective saccades to compensate for the residual position error at the end of the first saccade.

Both sound (s-) and galvanic (g-) vestibular-evoked myogenic potential (VEMP) enable us to study the saccular pathways. However, the VEMP can be abnormal for non-vestibular factors, such as insufficient activation of the sterno-cleido-mastoid (SCM) muscle or a lesion that involves the accessory nucleus and/or nerve or the SCM muscle. These drawbacks do not affect another technique that evaluates the saccular function: the N3 potential. We recorded both the s- and the g-VEMP and the N3 potential in a group of 31 healthy subjects to establish a reference range. The N3 potential and the s-VEMP were recordable bilaterally from all the subjects, whereas the g-VEMP was undetectable uni- or bilaterally in 7 subjects. The latency and amplitude values of the s-VEMP did not differ from those of the g-VEMP. For all three techniques, the latency and amplitude values from the right and from the left recording and/or stimulation side were the same. We suggest using normative latency and amplitude values based on the mean and ratio of the right- and left-side values. The s-VEMP, the N3 potential and the auditory evoked response (ABR) were compared in 15 subjects suffering from multiple sclerosis. The three techniques detected a similar number of abnormalities, but these abnormalities were not correlated. This suggests that these different techniques should be regarded as complementary in evaluating saccular function.

We focused on the saccade disconjugate control in idiopathic Parkinson's disease patients. Our data showed that in IPD patients the saccade precision was differently impaired in the two eyes--namely, the disconjugate component was larger than in controls--more for the remembered than for the reflexive task.