77 research outputs found
The effect of prolonged monocular occlusion on latent nystagmus in the treatment of amblyopia
We recorded eye movements in 5 patients with latent nystagmus (LN) before and after 2 days of occlusion of the better eye. The slow-phase speed of the nystagmus (SPS) was in general, before occlusion, lower when the better eye fixated but, after occlusion, lower when the worse eye fixated. However, the sum of SPS during right fixation and SPS during left fixation remained constant. Oscillopsia complaints gradually disappeared during the period of occlusion. These findings indicate that the difference between the SPS during fixation with the right eye and the SPS during fixation with the left eye in LN patients is caused by a compensatory drift that decreases LN during fixation with the better eye but increases LN during fixation with the worse eye. During occlusion, this compensatory drift changes its direction and magnitude slowly over days. Hence, occlusion of the better eye in children with amblyopia and LN should be prescribed only in days per week, not in hours per day
The length-tension diagrams of human oblique muscles in trochlear palsy and strabismus sursoadductorius
We determined the relation between length and tension in detached oblique muscles of 16 strabismus patients that underwent surgery, before and during contraction evoked by intravenous administration of succinylcholine. We frequently found a nonlinear relation between length and tension, unlike our previous findings in recti. In superior oblique palsies, the superior oblique was found, before injection of succinylcholine, to be stiff after elongation, and did not contract after injection of succinylcholine, while the ipsilateral inferior oblique contract after injection of succinylcholine, but with a higher spring constant than did usual. In 3 cases the superior oblique contracted vividly after administration of succinylcholine despite the presence of excyclotropia, stereopsis, torticollis (2 cases) and a hypertropia that increased in adduction, in downgaze, in adduction-and-downgaze and on ipsilateral head-tilt. The finding of a vividly contracting superior oblique is incompatible with the diagnosis of a complete superior oblique palsy. We conclude that some of the cases diagnosed as congenital superior oblique palsy, having a hypertropia increasing in adduction, in downgaze, in adduction-and-downgaze and on ipsilateral head-tilt, are in fact cases of unilateral strabismus sursoadductorius (upshoot in adduction), a non-paretic motility disorder
Automatic mental processes, automatic actions and behaviours in game transfer phenomena: an empirical self-report study using online forum data
Previous studies have demonstrated that the playing of videogames can have both intended and unintended effects. The purpose of this study was to investigate the influence of videogames on players’ mental processes and behaviours in day-to-day settings. A total of 1,023 self-reports from 762 gamers collected from online videogame forums were classified, quantified, described and explained. The data include automatic thoughts, sensations and impulses, automatic mental replays of the game in real life, and voluntary/involuntary behaviours with videogame content. Many gamers reported that they had responded – at least sometimes – to real life stimuli as if they were still playing videogames. This included overreactions, avoidances, and involuntary movements of limbs. These experiences lasted relatively short periods of time but in a minority of players were recurrent. The gamers' experiences appeared to be enhanced by virtual embodiment, repetitive manipulation of game controls, and their gaming habits. However, similar phenomena may also occur when doing other non-gaming activities. The implications of these game transfer experiences are discussed
Evaluation of vardenafil for the treatment of subjective tinnitus: a controlled pilot study
<p>Abstract</p> <p>Background</p> <p>Vardenafil (Levitra<sup>®</sup>) represents a potent and highly selective phosphodiesterase type 5 (PDE5) inhibitor, which is established for treatment of various diseases. There are several unpublished reports from patients stating that vardenafil has a considerable therapeutic effect on their concomitant tinnitus. This pilot study was conducted to specifically assess the effect of vardenafil in patients with chronic tinnitus.</p> <p>Methods</p> <p>This trial was based on a prospective, randomized, double-blind, placebo-controlled, parallel group design. Fourty-two consecutive subjects with mon- or binaural chronic tinnitus received 10 mg vardenafil (N = 21) or matching placebo tablets (N = 21) administered orally twice a day over a period of 12 weeks. Clinical examination and data acquisition took place at each visit: at baseline, after 4 weeks, after 12 weeks (end of treatment with study medication), and at non-medicated follow-up after 16 weeks. Assessment of clinical effectiveness was based on a standardized tinnitus questionnaire (TQ), the Short Form 36 health survey (SF-36), audiometric measurements (mode, pitch and loudness of tinnitus; auditory thresholds) and biomarkers of oxidative stress in patients' blood (malondialdehyde, protein carbonyl, homocysteine and total antioxidative status). Therapeutic efficacy was evaluated by comparison of subjective and objective parameters with baseline data between both treatment groups (ANCOVA).</p> <p>Results</p> <p>Vardenafil had no superior efficacy over placebo in the treatment of chronic tinnitus during this study. The primary efficacy criterion 'TQ total score' failed to demonstrate significant improvement compared to placebo. Subjective reports of TQ subscales and general quality of life areas (SF-36), objective audiometric examinations as well as investigated biomarkers for oxidative stress did not reveal any significant treatment effects. The safety profile was favorable and consistent with that in other vardenafil studies.</p> <p>Conclusion</p> <p>Although hypoxia and ischemia play a special role in the pathogenesis of tinnitus, the PDE5-inhibitor-induced increase of nitric oxide-mediated vasodilatation exerted no specific influence on tinnitus symptomatology. Considering the unclear risk of rarely associated hearing impairment, systemic application of vardenafil or other PDE5 inhibitors prove to be not appropriate for therapy of chronic tinnitus.</p
Age dependent normal horizontal VOR gain of head impulse test as measured with video-oculography
Synthesis and Properties of Molecular Probes for the Rescue Site on Mutant Cystic Fibrosis Transmembrane Conductance Regulator
Technological competence is a precondition for effective implementation of virtual reality head mounted displays in human neuroscience:A technological review and meta-analysis
International audienceImmersive virtual reality (VR) emerges as a promising research and clinical tool. However, several studies suggest that VR induced adverse symptoms and effects (VRISE) may undermine the health and safety standards, and the reliability of the scientific results. In the current literature review, the technical reasons for the adverse symptomatology are investigated to provide suggestions and technological knowledge for the implementation of VR head-mounted display (HMD) systems in cognitive neuroscience. The technological systematic literature indicated features pertinent to display, sound, motion tracking, navigation, ergonomic interactions, user experience, and computer hardware that should be considered by the researchers. Subsequently, a meta-analysis of 44 neuroscientific or neuropsychological studies involving VR HMD systems was performed. The meta-analysis of the VR studies demonstrated that new generation HMDs induced significantly less VRISE and marginally fewer dropouts. Importantly, the commercial versions of the new generation HMDs with ergonomic interactions had zero incidents of adverse symptomatology and dropouts. HMDs equivalent to or greater than the commercial versions of contemporary HMDs accompanied with ergonomic interactions are suitable for implementation in cognitive neuroscience. In conclusion, researchers' technological competency, along with meticulous methods and reports pertinent to software, hardware, and VRISE, are paramount to ensure the health and safety standards and the reliability of neuroscientific results
The Interaction of the Human Linear Otolith-Ocular and Angular Horizontal Vestibulo-Ocular Reflexes in Darkness
Vestibular Consequences of mTBI
Damage to vestibular function is a common and under-recognized consequence of mild Traumatic Brain Injury. Untreated vestibular disorders can lead to vertigo, imbalance, and slow improvement after mTBI. Fortunately, diagnosis and management of vestibular dysfunction, if made routine, can be quickly and successfully carried out. Common conditions, including Benign Positional Vertigo, can be detected by history and verified and treated by bedside testing. Simple medical management and, crucially, directed physical therapy can greatly improve the condition of most patients. In this chapter, an algorithmic approach is presented to assist in the diagnosis and management of vestibular system problems after head injury
- …