ISSN:1350-7540    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:1350-7540    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Lesions of the extrastriate cerebral cortex result in disorders of vision, which reveal two cortical processing streams extending ventrally and dorsally from the primary visual cortex. Current theories emphasize the visual perceptual and visuomotor specialization of the ventral and dorsal streams, respectively. Recent investigations of hemi-spatial neglect suggest that the inferior parietal region may lie at the junction of the visual and motor processing pathways.

ISSN:1350-7540    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Despite their different sensorimotor functions, saccades, pursuit eye movements, small-field optokinetic nystagmus and visual motion stimulation with the eyes stationary evoke a common complex pattern of activation in various cortical, basal ganglia, brain-stem and cerebellar areas. On closer inspection, however, typical subregions can be delineated that allow differentiation of adjacent but separate loci for specific functions (e.g. the separation of the two parallel corticocortical systems to control saccades and pursuit in the cortical eye fields). It is becoming increasingly clear that stimulation of one sensory system affects other sensory systems, and generally this is via an inhibitory reciprocal mode of interaction. For example, vestibular stimulation deactivates the visual cortex and visual stimulation deactivates the vestibular cortex.

ISSN:1350-7540    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

The number of recently published papers on motion sickness may convey the impression that motion sickness is far from being understood. The current review focusses on a concept which tends to unify the different manifestations and theories of motion sickness. The paper highlights the relations between ergonomic principles to minimise motion sickness and the concept predictions. The clinical management of sufferers from motion sickness in terms of selection, pharmacological measures and desensitisation courses is treated as well.

ISSN:1350-7540    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

This is a very brief update on the major papers since August 1998. Unilateral vestibular loss causes oculomotor, postural and sensory symptoms, all of which would be appropriate responses in a healthy person to a strong maintained angular and linear acceleration stimulus directed towards the healthy side. Within hours or days these static symptoms (so called because they are present without any externally imposed vestibular stimulation) reduce, and their progressive disappearance is called ‘vestibular compensation’. However, careful testing with natural vestibular stimuli shows that the dynamic vestibular response after unilateral vestibular loss to passively imposed vestibular stimuli does not recover; it is usually asymmetric and functionally ineffective. Major recent developments are: (1) the permanent asymmetrical and functionally ineffective dynamic rotational vestibulo-ocular reflex responses to passive natural vestibular stimulation after unilateral vestibular loss and canal blocks in human patients; (2) evidence for the substitution of other sensory input and responses during vestibular compensation; (3) perceptual testing using visual perception of a horizontal line to confirm permanent otolith dysfunction; (4) the clear and substantial differences in post-unilateral vestibular loss vestibulo-ocular reflex responses between passive and active head turning; and (5) new results in brainstem physiology explaining the disappearance of static symptoms.

ISSN:1350-7540    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

In the past year significant advances have been made in our understanding of the neurochemistry and neuropharmacology of the peripheral and central vestibular systems. The recognition of the central importance of excitatory amino acids and their receptors at the level of the hair cells, vestibular nerve and vestibular nucleus has progressed further, and the role of nitric oxide in relation to activation of theN-methyl-D-aspartate receptor subtype is becoming increasingly clear. Increasing evidence suggests that excessiveN-methyl-D-aspartate receptor activation and nitric oxide production after exposure to aminoglycoside antibiotics is a critical part of hair cell death, and new pharmacological strategies for preventing aminoglycoside ototoxicity are emerging as a result. Conversely, the use of aminoglycosides to lesion the peripheral vestibular system in the treatment of Meniere's disease has been studied intensively. In the vestibular nucleus, new studies suggest the importance of opioid, nociceptin and glucocorticoid receptors in the control of vestibular reflex function. Finally, the mechanisms of action and optimal use of antihistamines in the treatment of vestibular disorders has also received a great deal of attention.

ISSN:1350-7540    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Since the initial introduction of exercises as a treatment for patients with vestibular deficits, there have been numerous clinical reports on the benefits of treatment. Clinical reports, however, are of limited use as a basis for treatment because, without a control group, they offer only interesting descriptions of the patient populations. Fortunately, several prospective, randomized studies on the treatment of patients with vestibular hypofunction or with benign paroxysmal positional vertigo have been published recently, adding to the small number of previous publications. This review will examine the information provided by those studies. Advances in the use of outcome measures, assessment of otolith function and treatment of related balance problems are also presented.

ISSN:1350-7540    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Recent data indicate that diffusion/perfusion weighted imaging could eventually play a significant role in acute stroke management, particularly in determining the suitability of acute stroke patients for thrombolytic therapy. The evidence supporting these uses is reviewed, and the future role of diffusion and perfusion weighted imaging in acute stroke management is discussed.

ISSN:1350-7540    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

A relatively small number of studies were published on the intra-arterial therapy of stroke in the past year. Those reports, however, do offer strong evidence for the feasibility and safety of this therapeutic approach. Partly on the basis of these data it has become evident that the intra-arterial thrombolytic therapy of acute ischemic stroke is at least as effective as intravenous thrombolysis. There remain, however, many unresolved issues before such therapy can become a part of the standard of care.

ISSN:1350-7540    

出版商:OVID    

年代:2000

数据来源: OVID