China
Africa
Explore chapters and articles related to this topic
Rotary wing operations
Published in Nicholas Green, Steven Gaydos, Hutchison Ewan, Edward Nicol, Handbook of Aviation and Space Medicine, 2019
Nicholas Green, Steven Gaydos, Hutchison Ewan, Edward Nicol
Accidents and survivability. Risks include low-altitude/low-airspeed operations, night flying and reliance on night vision devices, degraded ambient conditions (degraded visual environment), ground obstacles (see Chapters 17, 18 and 35).Spatial disorientation (see Chapter 27). Cause of significant RW accidents; disproportionate severity with respect to loss of life/aircraft destruction.Brownout/blowing dust; whiteout/snow, fog/smoke, low illumination.
Management of residual physical deficits
Published in Mark J. Ashley, David A. Hovda, Traumatic Brain Injury, 2017
Velda L. Bryan, David W. Harrington, Michael G. Elliott
Information regarding driving behavior may be revealing. For example, are there times of day or night or certain areas that the individual avoids driving? Does the person get lost more often than usual? Does the driving behavior show impulsiveness and poor safety awareness or judgment? Does dizziness occur? Is anxiety increased when driving? Confusing visual perceptions, movement imperceptions, and spatial disorientation can produce frightening and disabling effects.65,87–89 An interview of the injured person may not be adequate when the traumatic injury has involved the frontal lobes. Poor insight or loss of insight is a frequent deficit exhibited after frontal lobe injury, and the person may fail to recognize the functional implications because they believe they have the necessary skills to drive. Studies have reported that 39%–46% of those who sustained a severe brain injury return to driving; however, only 24%–37% of those who returned to driving participated in a formal driving assessment.90,91
The Airplane:Another Solution to Transportation in a Rural Private Practice
Published in Florence S. Cromwell, Private Practice in Occupational Therapy, 2013
The pilot's limitations must also be respected and accepted. A VFR rated pilot needs to avoid IFR conditions. Spatial disorientation, to the point of not even knowing which way is up, is possible. The training for IFR flying teaches the pilot to trust the airplane's instruments and ignore the body's vestibular system.
Central vestibular dysfunction: don’t forget vestibular rehabilitation
Published in Expert Review of Neurotherapeutics, 2022
Sulin Zhang, Dan Liu, E. Tian, Jun Wang, Zhaoqi Guo, Weijia Kong
Pathogenesis of VM is still poorly understood and researchers fail to agree regarding whether its origin is predominantly central or peripheral. The factors involved in the pathogenesis of VM do not work separately but are intricately interwoven [81,82]. Abnormal sensory modulation or integration within the thalamo-cortical network could result in dizziness and spatial disorientation, which may lead to a ‘higher level’ dysfunction of the multisensory integration function of spatial orientation. Activities such as ballet dancing and yoga can enhance spatial perception and physical coordination [64]. Cortical spreading depression hypothesis assumes that, during aura migraine, various factors stimulate the cerebral cortex and then the inhibitory cortical electrical activity spreads from the stimulation site to the surrounding regions. Vestibular connections can be divided into downward-projecting vestibulospinal tracts and upward projections [i.e. to the ocular motor nuclei that organize the VOR] [83]. When it diffuses to the vestibular cortex (the parietal lobe and insular lobe), the activity is inhibited, and the inhibitory effect on the brainstem vestibular nucleus is weakened, thereby affecting the processing of vestibular signals and causing vestibular symptoms, or leading to transient vestibulo-ocular dysfunction or vestibular hypersensitivity associated with migraine [84].
White Matter Hyperintensities (WMH) and clinical outcome after vestibular neuritis
Published in Neurological Research, 2022
Huimin Fan, Jing Feng, Melissa Wills, Liying Wang, Xiaomeng Chen, Xiaokun Geng, Yuchuan Ding
All subjects with acute vestibular neuritis admitted to the Department of Neurology of Beijing Luhe Hospital affiliated with Capital Medical University from 2018 to 2020 were retrospectively identified based on the clinical criteria for VN. They were screened according to our inclusion and exclusion criteria. The inclusion criteria were as follows: (1) first attack of acute vertigo lasting more than 24 h, associated nausea, vomiting, and unsteadiness. (2) spontaneous horizontal–torsional nystagmus with a fast phase towards the healthy side. (3) positive head impulse test to the other side. The exclusion criteria were prior experience of vertigo attacks, combined hearing impairment or tinnitus, and any other neurologic deficit. The subjects who received a 4-test battery of caloric irrigation, video HITs (vHITs), cVEMPs and oVEMPs, as well as 3.0T brain MRI, were included in the present study. In addition, we recruited the healthy subjects to characterize the profiles of acute vestibular neuritis using 4-test battery tests of otolith and semicircular canal function. The patients were divided into two groups according to symptoms after 3 months. Group one consisted of patients who completely recovered within 3 months of symptoms onset (they had no dizziness, unsteadiness, or spatial disorientation). Group two consisted of patients who persistently suffered from symptoms of dizziness, unsteadiness, and spatial disorientation within 3 months of symptom onset.
Vertigo in childhood: an overview
Published in Hearing, Balance and Communication, 2021
Cristiano Balzanelli, Daniele Spataro, Luca Oscar Redaelli de Zinis
The motor skills of a subject from childhood to adulthood develop progressively according to maturation steps of the Cochleo-vestibular System, the vestibular reflexes (Vestibulo-Oculomotor Reflex – VOR; Vestibulo-Collic Reflex – VCR; Vestibulo-Spinal Reflex – VSR), the CNS, the Limbic System and the Musculoskeletal System. Vestibular input and hippocampal control allow the critical analysis of the congruence between the afferent sensory input to the CNS (sight, proprioception, spatial memory) and the efferent motor ones, in order to allow the most suitable motor response (navigation), of the all subverted in the event of a uni- or bilateral vestibular lesion, congenital or acquired, with consequent inevitable implications in the child’s daily life [13]. The deficit of the VOR, the VCR, and/or the VSR induce in fact a difficulty in maintaining the visual image on the retina and in processing the position of the body in space, an incorrect assessment of distances and a high risk of falls. Furthermore, the reduced hippocampal input can lead to behavioural disorders, such as poor affectivity, aggression, anxiety, insomnia, depression, up to multiple cognitive deficits in memory, attention and learning. Poor manual skills, delay in speaking, reading, walking, cycling, drawing, going up and down the stairs and spatial disorientation may result [13–15].