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To address the problem of accurate assessment of training effects of flight simulators, an intelligent algorithm using neural networks and reinforcement learning is proposed in the paper. The multi-dimensional data of facial expression features and EEG and EM physiological signals are analyzed, and a new evaluation model for assessing human spatial balance, attention distribution, neurological weakness and other pilot training states is studied through facial expression experiments mainly and eye-movement and EEG experiments supplemented, and the EEG acquisition and analysis during pilot training subjects (take-off and landing) are completed, and the emotional characteristics of pilots during training are identified. We completed data fusion of multi-dimensional channels, constructed mathematical models of pilot maneuver reaction time and attention allocation, monitored and evaluated flight training effects and conducted controlled experiments. The experimental results show that the average recognition rates of 92.598% and 87.013% were achieved for expression and neurasthenia recognition, and the human ergonomic information of facial expression and EEG and eye movements were effectively fused.

Spatial disorientation in airplane pilots is a leading factor in many fatal flying accidents. Spatial orientation is the product of integrative inputs from the proprioceptive, vestibular, and visual systems. One condition that can lead to sudden pilot incapacitation in fight is vestibular neuritis. Vestibular neuritis is commonly diagnosed by a finding of unilateral vestibular failure, such as a loss of caloric response. However, because caloric response testing reflects the function of only the superior part of the vestibular nerve, it cannot detect cases of neuritis in only the inferior part of the nerve. We describe the case of a Chinese naval command fighter pilot who exhibited symptoms suggestive of vestibular neuritis but whose caloric response test results were normal. Further testing showed a unilateral loss of vestibular evoked myogenic potentials (VEMPs). We believe that this pilot had pure inferior nerve vestibular neuritis. VEMP testing plays a major role in the diagnosis of inferior nerve vestibular neuritis in pilots. We also discuss this issue in terms of aeromedical concerns.

This paper proposed a new facial feature points localization algorithm based on main characteristics of eyes.Use the result of pupil center position to initialize the model of hybrid improved active shape model (ASM) and active appearance model (AAM). The algorithm will use two-dimensional local gray information to update the feature point position when using ASM to locate the face contour feature points. As to the internal features point location, it establishes facial organs independent AAM model. At the same time, it optimizes measure functions of ASM and AAM to judge the convergence of search algorithm. The experimental results show that the new algorithm greatly improved the localization accuracy of facial feature points.

Head and eye movement is eye movement response to head movements ,the eyes are the signals generated by the vestibular system is movement.The vestibular system is important to feel the organs and tissues of the body movement,Can be said that the vestibular system response to head movement, eye movement associated with the vestibule.We can use eye movements comparing with normal eye movements to detect whether the dizziness,in this process the modeling of the vestibular system is very important.Paper summarizes the response of head and eye movement system, vestibular system in the head and eye movement systems vestibular system exercise and Research at home and abroad, raised modeling method of the head and eye movement system when turn the head.

INTRODUCTION Excellent vestibular function (including utricular function) is important for pilots to maintain correct spatial orientation during flight. Vestibular-evoked myogenic potential (VEMP) recorded from extraocular muscles, the so-called ocular VEMP (oVEMP), can be used to evaluate utricular function. However, oVEMP has not been applied to pilots because of lack of reliable normative data. Hence, this study is designed to establish preliminary normative data for oVEMP induced by air-conducted sound in pilots and student pilots. METHODS There were 62 healthy student pilots (30 male and 32 age-matched female) and 31 healthy male fighter pilots who were recruited as study participants. During binaural air-conducted sound stimulation oVEMP was recorded bilaterally. The latencies of nI and pI, nI-pI interval, peak-to-peak nI-pI amplitude, and asymmetry ratio (AR) of oVEMP in all participants were collected. Meanwhile, the effects of gender and age on oVEMP were also investigated. RESULTS The latencies of nI and pI, nI-pI interval, nI-pI interpeak amplitude, and AR of oVEMP in all participants were 10.35 +/- 0.66 ms, 15.18 +/- 1.07 ms, 4.75 +/- 0.99 ms, 6.75 +/- 4.13 microV, and 13.22 +/- 9.13%, respectively. No significant difference existed between male student pilots and male pilots in terms of oVEMP parameters. The only significant difference was the nI-pI amplitude between age-matched male and female student pilots: 6.96 +/- 3.85 microV for male student pilots and 5.47 +/- 3.10 microV for female student pilots. CONCLUSIONS oVEMP should be interpreted with the AR rather than raw amplitude itself. Each institution should determine its own normal values.

Background Effects of high Gz acceleration can threaten flight safety through loss of consciousness or a lesser-known phenomenon, G-induced vestibular dysfunction (GIVD). There are reports of GIVD following high-G flight or centrifuge exposure. The aim of this study was to explore this problem under controlled conditions using a human centrifuge. Methods There were 11 pilots who were exposed to +9 Gz for 10 s. Measurements were made before and after G exposure to assess vestibular function, including spontaneous nystagmus, positioning nystagmus, optokinetic nystagmus, vestibular ocular reflex, vestibular-vision interaction, subjective vision vertical perception, and vestibular-evoked myogenic potentials. Results No significant change was found for vestibular function after the Gz exposure. Conclusion It appears +9 Gz for 10 s does not produce GIVD. However, the possible effects of prolonged high G maneuvers in modern aircraft combined with head movements may warrant further study.

Background Anatomic and electrophysiological studies have revealed that the neurons located in the media vestibular nuclei (MVN) receive most of the sensory vestibular input coming from the ipsilateral labyrinth and the responses of MVN neurons to caloric stimulation directly reflect changes in primary vestibular afferent activity. The aim of this study was to clarify the intrinsic characteristics of serotonin (5-hydroxytryptamine, 5-HT) release in the MVN during the period of vertigo induced by caloric stimulation. Methods We used an in vivo microdialysis technique to examine the effects of caloric stimulation on the serotoninergic system in MVN. Twenty four guinea pigs were randomly divided into the groups of irrigation of the ear canal with hot water (n = 6), ice water (n = 6) and 37 degrees C water (n = 4), and the groups of irrigation of the auricle with hot water (n = 4) and ice water (n = 4), according to different caloric vestibular stimulation. We examined the animal's caloric nystagmus with a two-channel electronystagmographic recorder (ENG), and meanwhile examine serotonin (5-hydroxytryptamine, 5-HT) level in the MVN with microdialysis technique after caloric stimulation. Results In the caloric test the hot water (44 degrees C) irrigation of the right external auditory canal induced horizontal nystagmus towards the right side lasting about 60 seconds and the ice water irrigation of the right external auditory canal induced it towards the left side lasting for about 90 seconds. No nystagmus was induced by 37 degrees C water irrigation of the external ear canal. Therefore, it was used as a negative control stimulation to the middle ear. The MVN 5-HT levels significantly increased in the first 5-minute collecting interval and increased to 254% and 189% of the control group in the second collecting interval in response to caloric vestibular stimulation with ice water and hot water respectively. The serotonin release was not distinctly changed by the irrigation of the auricle with ice water or hot water. Conclusions Neither somato-sensory stimulation of the middle ear nor nonspecific cold or hot stress affects the serotonin release. The rise of 5-HT in MVN may be involved in the mechanism of vertigo induced by caloric stimulation.

To observe the characteristics of vestibular-ocular reflex (VOR) of guinea pigs during eccentric sinusoidal rotation in different frequencies and radius, and compare them with that during axis rotation, obtain the parameters which reflect otolith functions, and provide experimental evidence for the establishment of otolith function test.Guinea pigs were placed in axis of rotation and in an heading out eccentric position apart from rotation axis of 330 mm, 660 mm and 990 mm respectively, their VOR were recorded and compared under stimulus of sinusoidal rotations in the frequencies of 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6 Hz with the peak velocity of 60 degrees/s in each position.Both frequency and eccentric radius had significant effects on the VOR gain, it increased with the increase of frequencies and radius. The largest increase of the gain occurred at the frequencies of 0.3 and 0.4Hz, and no significant changes were observed above these frequencies.Enhancement ratio (ER) of VOR gain can reflect the extent of its increase with radius, and can be used as an index of otolith function, the stimulus profile of eccentric rotation at frequency of 0.4Hz and radius of 990mm is recommended as the stimulus profile for the otolith function test.

To clarify the clinical significance of vibration-induced nystagmus (VIN) and to calculate the sensitivity and the specificity of the vibration test.One hundred and twelve patients with unilateral peripheral vestibular disorders and 30 normal subjects were enrolled into this study. However, patients with spontaneous nystagmus were excluded. Vibratory stimuli (approximately 92Hz) were presented to the mastoids and the forehead. Patients and normal subjects also underwent head shaking testing and caloric testing.Of the 112 patients, 91 (81%) showed VIN which were mainly horizontal. VIN was more frequently evoked on the mastoids than on the forehead. In the majority of patients (76 cases), the direction of VIN was toward the healthy side, whereas patients with Meniere's disease (15 cases), showed nystagmus toward the affected side. None of 30 normal subjects showed VIN. Whereas, HSN was found in 70 (63%) patients and 9 (30%) in normal subjects. Of 112 patients, 10 showed a canal paresis (CP) value of caloric test less than 25% ,while 32 with a CP value between 25% and 40%, 48 with a CP value between 40% and 70%, and 22 with a CP value more than 70%. It is notable that with increasing canal paresis value on caloric testing, VIN was more likely to be evoked.VIN testing is a simple, non-invasive and well-tolerated clinical test that indicates unilateral peripheral vestibular dysfunction. VIN testing had greater sensitivity and the specificity than HSN testing in the diagnosis of unilateral peripheral vestibular disorders.

This study was undertaken to analyze and evaluate the diagnosis and principal treatment methods for congenital choledochal cyst, focusing on various surgical procedures and clinical outcome. A comprehensive, retrospective study was conducted on 72 adult patients who presented with choledochal cyst from 1985 to 2002. Surgical procedures were cyst excision with hepaticojejunostomy in 25 cases for type I or type IV-B, extrahepatic cyst excision with hepaticojejunostomy in 8 cases for type IV-A, extrahepatic cyst excision with modified hepaticojejunostomy in 2 cases for type IV-B, non-cyst excision with or without hepaticojejunostomy in 27 cases for types I, II, IV-A, IV-B. The early postoperative morbidity and mortality rate were 16.1% (9/62) and 6.5% (4/62) respectively, and the complication rate related to surgical procedure was 30.6% (19/62). The incidence of cholangiocarcinoma with non-cyst excision or non-operated congenital choledochal cyst was 10.8% (4/37). One patient died of primary hepatocellular carcinoma after cyst excision with hepatojejunostomy. In conclusion, our results showed that complete exci-sion of choledochal cyst for types I, II, and IV-B and complete excision of extra-hepatic choledochal cyst from the hepatic hilum in type IV-A with hepaticojejunostomy or modified hepaticojejunostomy are the treatment of choice for choledochal cyst in adult patients.

To explore if high G exposure can cause vestibular disorder in guinea pig and the possibility of preventing it by preconditioning with exposure to a low hypergravity environment before high G stimulus.A total of 86 guinea pigs were divided into 4 groups: 1) 28 were treated with a stimulus of +10 Gy for 5 min (+10 Gy group); 2) 28 were preconditioned by exposure to 2 G environment for 8 d before the +10 Gy stimulus (preconditioning group); 3) 20 were exposed to 2 G environment for 8 d, but without +10 Gy stimulus (2 G group); the rest 10 served as control. Their vestibular related behaviour, including vestibulo-spinal reflex (VSR) and vestibulo-ocular reflex (VOR) such as head tremble, head deviation, spontaneous nystagmus, eye deviation, body tilt or looping, were observed directly, the choline acetyltransferase (ChAT) activity in VNC (vestibular nucleon complex) in brain stem were investigated by immunohistochemistry technique, and the relative gamma in each group were analysed.The incidence of behavioral abnormalities (BA) in 10 Gy group (79%) is significantly higher than that in preconditioning group (50%). The relative gamma of staining showed that the content of ChAT in VNC of the +10 Gy group and preconditioning group were significantly higher than that in control group, but no difference was found between them in +10 Gy and preconditioning groups.High G exposure of +10 Gy for 5 min could cause vestibular disorders in guinea pigs, and preconditioning with pre-exposure to 2 G environment could alleviate it. ChAT activity changes in VNC may contribute to its mechanisms.