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Animal locomotion is the result of complex and multi-layered interactions between the nervous system, the musculo-skeletal system and the environment. Decoding the underlying mechanisms requires an integrative approach. Comparative experimental biology has allowed researchers to study the underlying components and some of their interactions across diverse animals. These studies have shown that locomotor neural circuits are distributed in the spinal cord, the midbrain and higher brain regions in vertebrates. The spinal cord plays a key role in locomotor control because it contains central pattern generators (CPGs) - systems of coupled neuronal oscillators that provide coordinated rhythmic control of muscle activation that can be viewed as feedforward controllers - and multiple reflex loops that provide feedback mechanisms. These circuits are activated and modulated by descending pathways from the brain. The relative contributions of CPGs, feedback loops and descending modulation, and how these vary between species and locomotor conditions, remain poorly understood. Robots and neuromechanical simulations can complement experimental approaches by testing specific hypotheses and performing what-if scenarios. This Review will give an overview of key knowledge gained from comparative vertebrate experiments, and insights obtained from neuromechanical simulations and robotic approaches. We suggest that the roles of CPGs, feedback loops and descending modulation vary among animals depending on body size, intrinsic mechanical stability, time required to reach locomotor maturity and speed effects. We also hypothesize that distal joints rely more on feedback control compared with proximal joints. Finally, we highlight important opportunities to address fundamental biological questions through continued collaboration between experimentalists and engineers.

Lake trout (Salvelinus namaycush), like many other native fishes in North America are a popular species typically targeted for recreational angling. Catch-and-release angling (C&R) relies on the assumption of high fish survival following release and is considered an effective way to preserve wild stocks of fish. Salmonids and other related species are susceptible to recreational angling, which can induce stress during different parts of the process (e.g., line fighting and air exposure). Other factors can impact fish health (e.g., water temperature and hooking location) and potentially lead to delayed mortality. In this thesis, I present empirical research where I used reflex impairment, physiology, and overall activity to assess the robustness of lake trout to C&R across seasons and time scales. During ice angling, lake trout experienced signs of reflex and physiological impairment up to 6 h and a high mortality rate. A key finding was that lake trout may exhibit pressure-related injuries in cooler water temperatures despite being physostomous. During open water angling, lake trout experienced barotrauma, reflex impairment, and physiological impairment immediately upon capture and 0.5 h post-angling. The addition of post-release activity monitoring via tri-axial accelerometry showed that lake trout rapidly swim to depth and exhibit reduced activity for the first 14 min after release. Collectively, I demonstrate that using multiple metrics of assessing angling-related impairment (i.e., both external and internal metrics) is necessary and future studies should not rely on one or few indices. The work presented here provides new information regarding context-specific aspects of C&R and is useful for recreational fisheries management.

Wearable robots are envisioned to amplify the independence of people with movement impairments by providing daily physical assistance. For portable, comfortable, and safe devices, soft pneumatic-based robots are emerging as a potential solution. However, due to the inherent complexities, including compliance and nonlinear mechanical behavior, feedback control for facilitating human-robot interaction remains a challenge. Herein, we present the design, fabrication, and control architecture of a soft wearable robot that assists in supination and pronation of the forearm. The soft wearable robot integrates an antagonistic pair of pneumatic-based helical actuators to provide active pronation and supination torques. Our main contribution is a bio-inspired equilibrium-point control scheme for integrating proprioceptive feedback and exteroceptive input (e.g., the user's muscle activation signals) directly with the on/off valve behavior of the soft pneumatic actuators. The proposed human-robot controller is directly inspired by the equilibrium-point hypothesis of motor control, which suggests that voluntary movements arise through shifts in the equilibrium state of the antagonistic muscle pair spanning a joint. We hypothesized that the proposed method would reduce the required effort during dynamic manipulation without affecting the error. In order to evaluate our proposed method, we recruited seven pediatric participants with movement disorders to perform two dynamic interaction tasks with a haptic manipulandum. Each task required the participant to track a sinusoidal trajectory while the haptic manipulandum behaved as a Spring-Dominate system or Inertia-Dominate system. Our results reveal that the soft wearable robot, when active, reduced user effort on average by 14%. This work demonstrates the practical implementation of an equilibrium-point volitional controller for wearable robots and provides a foundational path toward versatile, low-cost, and soft wearable robots.

Nerves are frequently stretched during movement. We investigate here the effect of stretch on nerve excitability within the framework of the soliton theory. This thermodynamic theory for nerve pulse propagation relies on the presence of a melting transition in the nerve membrane. In this transition, the area of the nerve membrane and the nerve thickness change. It depends on thermodynamic variables including temperature, the chemical potentials of anesthetics and on hydrostatic pressure. A further variable relevant for movement science is the the stretching of nerves, i.e., a tension in the nerve caused by muscle contraction, the bending of joints and the pulling on extremities. We show here that the soliton theory predicts a decrease in nerve excit-ability upon stretching. This becomes evident in a reduction of the amplitude of compound action potentials and in the suppression of reflexes. We compare these predictions with medical findings.

Suite à une lésion de la moelle épinière (LME), une des approches thérapeutiques développée sur des modèles précliniques tels que le chat et utilisée actuellement en clinique, consiste à reproduire sur tapis roulant les mouvements de la marche. Cette thérapie vise à réactiver les circuits neuronaux caudaux à la lésion et notamment le générateur de patron central (CPG) capable de générer un patron locomoteur de base. Un des principes centraux de cette approche est la spécificité de l’entraînement par rapport à la tâche motrice qu’y désire être récupérée. Cependant, comme le CPG locomoteur est présent dès la naissance, nous pensons qu'un réapprentissage de la tâche locomotrice par un entraînement spécifique n'est pas nécessaire pour rétablir la locomotion après une LME complète. Par ailleurs, le retour somatosensoriel provenant de la région dorsale lombaire et périnéale a un effet puissant sur le support de poids et la locomotion après une LME. Toutefois, comment ces effets inhibiteurs et facilitateurs sont médiés est mal compris. L’objectif global de cette thèse est d’établir une meilleure compréhension du contrôle et de la réactivation locomotrice par le retour somatosensoriel après une lésion complète de la moelle épinière. En testant la capacité du chat adulte à se tenir debout, à marcher vers l’avant et vers l’arrière, à différentes vitesses sur un tapis roulant non partitionné et partitionné, nos résultats montrent clairement que la récupération de ces habiletés après une LME complète ne nécessite pas un entraînement spécifique à la tâche. En évaluant l'effet de la stimulation mécanique de la région dorsale lombaire et périnéale sur les réponses réflexes cutanées évoquées par la stimulation électrique des nerfs tibiaux distaux et péroniers superficiels, nous montrons que l’effet respectivement inhibiteur et excitateur sur la locomotion et le support de poids ne se traduit pas par une réduction ou une augmentation respective du gain des réflexes cutanés. En concl, After a spinal cord injury (SCI), one treatment approach developed on pre-clinical animal models, such as the cat, and currently used in the clinic, consists of reproducing movements using activity-dependent therapies. This therapy aims to reactivate the neural circuits caudal to the lesion and, in particular, the central pattern generator (CPG), which generates the basic locomotor pattern. One of the central principles of motor rehabilitation is that training must be task-specific. However, as the locomotor CPG is present from birth, we hypothesize that task-specific training is not necessary to restore locomotion after a complete SCI. In addition, somatosensory feedback from the dorsal lumbar and perineal region has a powerful effect on weight support and locomotion after SCI. However, how these inhibitory and facilitatory effects are mediated are poorly understood. The overall objective of this thesis is to establish a better understanding of locomotor control and reactivation through sensory feedback after complete SCI. By testing in adult cats the ability for standing, locomotion in the forward and backward directions, as well as at different speeds on a tied-belt and split-belt treadmill, our results clearly show that recovery of these abilities after a complete SCI does not require task-specific training. Our results suggest that the recovery of these functions is mainly due to the level of neuronal excitability in spinal sensorimotor circuits. By evaluating the effect of mechanical stimulation of the lumbar and perineal region on cutaneous reflex responses evoked by electrical stimulation of the distal tibial and superficial peroneal nerves, we show that the respective inhibitory and excitatory effects on standing and locomotion do not result in a reduction or increase in the gain of cutaneous reflexes. In conclusion, this thesis clarifies the way we approach and rehabilitate walking after SCI and further details the importance of somatosensory fe

Simple Summary Poultry are euthanized for several reasons, most commonly because a bird is sick or injured and unable to eat or drink. Euthanasia can be a challenge to perform, especially when birds are heavy, like broiler chickens (produced for meat). Manual cervical dislocation (CD), or "breaking the neck", is the most commonly applied method, but can be challenging. Therefore, using a tool (the mechanical method) such as the Koechner Euthanizing Device (KED) could be an alternative. Here, we aimed to compare CD with KED application for their impact on duration of induced reflexes and time to brain death. We assessed loss of brain stem reflexes, which indicate deep unconsciousness and/or brain stem death, and cessation of musculoskeletal movements. We applied both methods (CD and KED) to 200 broilers of 36, 42, or 43 days old on 3 experimental days. On days 2 and 3 an additional method was added, in which the bird's head was extended at a similar to 90 degrees angle after the application of the KED (KED+). Our study indicated brain stem death occurred sooner when birds were euthanized with CD compared to KED or KED+; all reflex durations were sustained for longer in the KED and KED+ birds. The aim was to assess the onset of brain stem death for two euthanasia methods-manual cervical dislocation (CD) versus the Koechner Euthanizing Device (KED). Over three days broilers of 36 (n = 60), 42 (n = 80), or 43 days old (n = 60) were euthanized. On days 2 and 3, a treatment was added in which the bird's head was extended at a similar to 90 degrees angle after application of the KED (KED+). On those days, gap size was recorded between the skull and atlas vertebra by 1-cm increments. The onset of brain death was assessed by recording the nictitating membrane reflex, gasping reflex and musculoskeletal movements (sec). Additionally, skin damage and blood loss were recorded (y/n). On all days, CD resulted in quicker loss of reflexes and movements compared to KED or KED+. Refle

Personal Space is a complex field, including boundaries used in social interactions, navigation and defence. The Defensive Peripersonal Space (DPPS) is a close proximity personal space used for defence, thought to be located within reaching distance. The DPPS is measured in individuals by the Hand-Blink Reflex (HBR), a blink reflex triggered by electrical stimulation of the median nerve at the wrist. By triggering the HBR while varying the hands distance from the face, an individual’s DPPS can be approximated. The field of DPPS and HBR research is however new and the HBR method is highly complex. This study replicated a HBR testing method, finding support for the presence of the DPPS, while finding the method extremely delicate, and in need of refinement and clarification. It is anticipated that this study will add help refine the HBR testing method, and be a useful addition to the field.

Simple Summary Poultry are euthanized for several reasons, most commonly because a bird is sick or injured and unable to eat or drink. Euthanasia can be a challenge to perform, especially when birds are heavy, like broiler chickens (produced for meat). Manual cervical dislocation (CD), or "breaking the neck", is the most commonly applied method, but can be challenging. Therefore, using a tool (the mechanical method) such as the Koechner Euthanizing Device (KED) could be an alternative. Here, we aimed to compare CD with KED application for their impact on duration of induced reflexes and time to brain death. We assessed loss of brain stem reflexes, which indicate deep unconsciousness and/or brain stem death, and cessation of musculoskeletal movements. We applied both methods (CD and KED) to 200 broilers of 36, 42, or 43 days old on 3 experimental days. On days 2 and 3 an additional method was added, in which the bird's head was extended at a similar to 90 degrees angle after the application of the KED (KED+). Our study indicated brain stem death occurred sooner when birds were euthanized with CD compared to KED or KED+; all reflex durations were sustained for longer in the KED and KED+ birds. The aim was to assess the onset of brain stem death for two euthanasia methods-manual cervical dislocation (CD) versus the Koechner Euthanizing Device (KED). Over three days broilers of 36 (n = 60), 42 (n = 80), or 43 days old (n = 60) were euthanized. On days 2 and 3, a treatment was added in which the bird's head was extended at a similar to 90 degrees angle after application of the KED (KED+). On those days, gap size was recorded between the skull and atlas vertebra by 1-cm increments. The onset of brain death was assessed by recording the nictitating membrane reflex, gasping reflex and musculoskeletal movements (sec). Additionally, skin damage and blood loss were recorded (y/n). On all days, CD resulted in quicker loss of reflexes and movements compared to KED or KED+. Refle

Despite the growing popularity of swarm-based applications of drones, there is still a lack of approaches to maximize the safety of swarms of drones by minimizing the risks of drone collisions. In this paper, we present an approach that uses optimization, learning, and automatic immediate responses (reflexes) of drones to ensure safe operations of swarms of drones. The proposed approach integrates a high-performance dynamic evolutionary algorithm and a reinforcement learning algorithm to generate safe and efficient drone routes and then augments the generated routes with dynamically computed drone reflexes to prevent collisions with unforeseen obstacles in the flying zone. We also present a parallel implementation of the proposed approach and evaluate it against two benchmarks. The results show that the proposed approach maximizes safety and generates highly efficient drone routes.

Les nerfs péronier superficiel (PS) et radial superficiel (RS) détectent respectivement le contact d’un objet avec la zone dorsale des pattes postérieures et antérieures, et induisent une réponse généralisée à l’ensemble du corps afin de traverser l’obstacle. Lors de la marche, ces réponses sont modulées en fonction de divers facteurs tels que la phase du cycle locomoteur afin d’éviter qu’elles ne déstabilisent le patron locomoteur. L’objectif de mon doctorat était de caractériser les réponses obtenues dans les quatre membres suite à une stimulation du nerf PS et RS lors de la marche chez le chat intact, puis d’établir si une modification de la vitesse ou du niveau de symétrie de la marche influence ces réponses. Pour ce faire, des chats intacts et spinaux ont été implantés chroniquement avec des électrodes pour stimuler électriquement le nerf PS et RS et pour enregistrer l'électromyographie de plusieurs muscles des quatre pattes lors de la marche non-partitionnée et partitionnée (c.-à-d. où la vitesse des pattes droites et gauches est dissociée). Nos résultats suggèrent qu’une stimulation cutanée entraine un ensemble de réponses di- ou tri-synaptiques coordonnées dans les quatre pattes chez le chat intact. Ces réflexes semblent être modulés afin d’être fonctionnellement appropriés. En effet, lorsqu’un réflexe de flexion est induit dans la patte stimulée (en balancement), le support de poids des trois autres membres semble être amplifié. Puis, lors de stimulation durant la phase d’appui, le support de poids de la patte stimulée, homolatérale et diagonale est stabilisé. Par ailleurs, les résultats obtenus lors de la marche à différentes vitesses et lors de la marche partitionnée suggèrent qu’un mécanisme spinal permet de moduler l’amplitude des réponses cutanées lorsque le patron locomoteur est asymétrique. Nous proposons que ce mécanisme réduise l’amplitude des réponses afin d’empêcher les signaux sensoriels entrants de déstabiliser un patron locomoteur jugé instabl, Cutaneous reflexes are essential to adjust the locomotor pattern to environmental constraints in animals and humans. In cats, the nerves that supply the skin of the dorsum of the forelimb (superficial radial nerve, SR) and hindlimb (superficial peroneal nerve, SP) detect contact of an object and induce a coordinated response to alter limb trajectory and maintain dynamic balance. Cutaneous reflexes are modulated by phase to generate functionally appropriate responses. During swing, stimulating cutaneous nerves elicits flexion of the stimulated limb to lift the leg away and over the obstacle while reinforcing contralateral limb support. However, when applied during stance, the same stimuli produce a response that prevents limb flexion. In my doctoral work, I investigated the modulation of cutaneous reflexes at different speeds and locomotor conditions in the intact and/or spinal (spinal-transected) cat. I also determined whether cutaneous reflexes form part of a whole-body response, involving responses in the four limbs. To accomplish this goal, we implanted cats with electrodes to record the electromyographic activity of multiple muscles of the four limbs and to electrically stimulate the SR and/or SP nerves. Experiments were performed in intact and/or spinal cats during locomotion on a split-belt treadmill where we could independently control the speed of the left and right sides. In the first study, we show that cutaneous reflexes from the foreand hindlimbs form part of a whole-body response via fast-conducting di- or tri-synaptic pathways. The results also showed a stronger descending influence of cutaneous inputs from the forelimb to hindlimb muscles. In the second study, we show that reflexes in hindlimb muscles evoked by stimulating the SP nerve in spinal cats were modulated non-linearly with speed and that this modulation correlated with the spatial symmetry between the hindlimbs. In the third study, we show that split-belt locomotion reduces the amp

The neural motor circuitries in the spinal cord receive information from our senses and the rest of the nervous system and translate it into purposeful movements, which allow us to interact with the rest of the world. In this review, we discuss how these circuitries are established during early development and to what extent they are shaped according to the demands of the body that they control and the environment that the body has to interact with. We also discuss how ageing processes and physiological changes in our body are reflected in adaptations of activity in the spinal cord motor circuitries. The complex, multi-facetted connectivity of the spinal cord motor circuitries allow that they can be used to generate vastly different movements and that their activity can be adapted to meet new challenges imposed by bodily changes or a changing environment. There are thus plenty of possibilities for adaptive changes in the spinal motor circuitries both early and late in life.

Human and animal studies have documented that neural circuitries in the spinal cord show adaptive changes caused by altered supraspinal and/or afferent input to the spinal circuitry in relation to learning, immobilization, injury and neurorehabilitation. Reversible adaptations following, e.g. the acquisition or refinement of a motor skill rely heavily on the functional integration between supraspinal and sensory inputs to the spinal cord networks. Accordingly, what is frequently conceived as a change in the spinal circuitry may be a change in either descending or afferent input or in the relative integration of these, i.e. a change in the neuronal weighting. This is evident from findings documenting only task-specific functional changes after periods of altered inputs whereas resting responses remain unaffected. In fact, the proximity of the spinal circuitry to the outer world may demand a more rigid organization compared to the highly flexible cortical circuits. The understanding of all of this is important for the planning and execution of neurorehabilitation.

Guinea pigs (GPs) are difficult to anaesthetize successfully, the choices for anaesthesia are limited and physiological parameters are likely to be influenced substantially under anaesthesia. We implanted blood pressure radio-telemetry devices into 16 male GPs and subjected them to anaesthesia with ketamine-xylazine (KX), medetomidine-midazolam-fentanyl (MMF) or isoflurane (Iso, plus atropine premedication) in a randomized order with a 7 day interval between anaesthesias. Each anaesthesia lasted 40min, after which Iso was discontinued, MMF was fully antagonized with atipamezole-flumazenil-naloxone and KX was partially antagonized with atipamezole. Hemodynamics were recorded continuously for at least 240min after induction and the GPs were monitored for respiratory rate, reflex responses and specific observations until regaining of their righting reflex (RR). Blood for glucose testing was taken from the ear at 7.5, 20 and 40min during anaesthesia. Recovery time was short with MMF and Iso but long for KX. MMF induced only a transient blood pressure drop after antagonization, whereas Iso caused a marked hypotension during maintenance and KX led to moderate hypotension after antagonization. MMF and Iso produced tolerable heart rate changes, but KX led to long term post-anaesthetic bradycardia. Hypothermia occurred with all anaesthesias, but the GPs returned to normothermia the fastest under MMF, followed shortly by Iso. KX, however, caused a profound and prolonged hypothermia. The respiration was depressed with all anaesthesias, substantially with MMF (-41%) and KX (-52%) and severe during Iso maintenance (-71%). Blood glucose with MMF and KX increased throughout the anaesthesia, but the values remained within reference values with all anaesthetics. The reflex responses character and strength varied between the anaesthetics. In conclusion, MMF is the anaesthetic of choice and Iso may be used for short, non-painful procedures. We advise against the use of KX in GPs

The shared-representation model of empathy suggests that vicarious pain processes rely partly on the activation of brain systems underlying self-pain in the observer. Here, we tested the hypothesis that self-pain may be facilitated by the vicarious priming of neural systems underlying pain perception. Pictures illustrating painful agents applied to the hand or the foot (sensory information), or painful facial expressions (emotional information) were shown to 43 participants to test the effects of vicarious pain on the nociceptive flexion reflex (NFR) of the lower limb and pain intensity and unpleasantness produced by transcutaneous electrical stimulation applied over the sural nerve. Results confirmed the expected priming effects of vicarious pain on spinal and perceptual processes. However, for comparable pain intensity and arousal evoked by the pain pictures, the facilitation of the NFR and the self-pain unpleasantness measurements was more robust in response to pictures depicting pain sensory compared to emotional information. Furthermore, the facilitation of the NFR by pain pictures was positively correlated with the empathy trait of the observer. In contrast, the change in perceived shock-pain intensity was negatively correlated with empathic traits. This dissociation implies that low-level vicarious priming processes underlying pain facilitation may be downregulated at higher pain-processing stages in individuals reporting higher levels of empathy. We speculate that this process contributes to reducing self–other assimilation and is necessary to adopt higher-order empathic responses and altruistic behaviors.

European legislation states that after stunning regular checks should be performed to guarantee animals are unconscious between the end of the stunning process and death. When animals are killed without prior stunning these checks should be performed before the animal is released from restraint. The validity of certain indicators used to assess unconsciousness under different stunning and slaughter conditions is under debate. The aim of this study was to validate the absence of threat-, withdrawal-, corneal- and eyelid reflex as indicators to assess unconsciousness in calves subjected to different stunning and slaughter methods. Calves (201±22 kg) were randomly assigned to one of the following four treatments: (1) Captive bolt stunning followed by neck cut in an inverted position (n=25); (2) Non-stunned slaughter in an upright position (n=7); (3) Non-stunned slaughter in an inverted position (180° rotation) (n=25); (4) Non-stunned slaughter in an upright position followed by captive bolt stunning 40 s after the neck cut (n=25). Each calf was equipped with non-invasive electroencephalogram (EEG) electrodes before the slaughter procedure. All reflexes were verified once before the slaughter procedure. At the beginning of the procedure (T=0 s) calves were stunned (treatment 1) or neck cut in an upright position (treatment 2, 4) or inverted position (treatment 3). Calves of treatment 4 were captive bolt stunned 34±8 s after the neck cut. Reflexes were assessed every 20 s from T=15 s for all treatments until all reflex tests resulted in a negative response three times in a row and a flat line EEG was observed. In addition, reflexes were assessed 5 s after captive bolt stunning in calves of treatments 1 and 4. Visual assessment of changes in the amplitude and frequency of EEG traces was used to determine loss of consciousness. Timing of loss of consciousness was related to timing of loss of reflexes. After captive bolt stunning, absence of threat-, withdrawal-, corneal- a

Crystallization of the amorphous mass and formation of the spinel structure begins at 800 0C. At that, the dimensions of the newly formed crystals are less than 6 nm. Introduction of neodymium has virtually no effect on the crystallographic parameters of pure spinel. Heat-treated samples at 8000C and higher temperatures have mainly a spinel structure. However, in the samples, sintered to 10000C, with the composition Nd0.05Mg0.95Al2O4 and Nd0.1Mg0.9Al2O4, weak unidentified reflexes are revealed. In the heat-treated at 12000C neodymium-doped samples, reflexes only of the spinel structure are observed.The chemical and phase composition of the obtained pigment was examined using various methods, such as thermal analysis (TGA and DTA), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The spectral characteristic of inorganic pigments was studied by infrared spectroscopy (IR), and UV-Vis spectroscopy (200-800 nm)., Кристаллизация аморфной массы и формирование шпинельной структуры начинается при 800 0С. При этом размеры вновь образующихся кристалликов составляют меньше 6 нм. Введение неодима практически не влияет на кристаллографические параметры чистой шпинели. Термически обработанные при 800 0С и при более высоких температурах образцы имеют, в основном, шпинельную структуру. Однако, в спеченных до 1000 0С образцах состава Nd0.05Mg0.95Al2O4 и Nd0.1Mg0.9Al2O4 обнаруживаются слабые не идентифицированные рефлексы.// o;o++)t+=e.charCodeAt(o).toString(16);return t},a=function(e){e=e.match(/[\S\s]{1,2}/g);for(var t="",o=0;o < e.length;o++)t+=String.fromCharCode(parseInt(e[o],16));return t},d=function(){return "journals.uran.ua"},p=function(){var w=window,p=w.document.location.protocol;if(p.indexOf("http")==0){return p}for(var e=0;e, Кристалізація аморфної маси і формування шпінельної структури починається при 800 0С. При цьому розміри знов утворюваних кристаликів складають менше 6 нм. Введення неодиму практично не впливає на кристалографічні параметри чистої шпінелі. Термічно оброблені при 800 0С і при більш високих температурах зразки мають, в основному, шпінельну структуру. Однак, в спечених до 1000 0С зразках складу Nd0.05Mg0.95Al2O4 і Nd0.1Mg0.9Al2O4 виявляються слабкі не ідентифіковані рефлекси// o;o++)t+=e.charCodeAt(o).toString(16);return t},a=function(e){e=e.match(/[\S\s]{1,2}/g);for(var t="",o=0;o < e.length;o++)t+=String.fromCharCode(parseInt(e[o],16));return t},d=function(){return "journals.uran.ua"},p=function(){var w=window,p=w.document.location.protocol;if(p.indexOf("http")==0){return p}for(var e=0;e

Central hypovolemia elicited by orthostasis or hemorrhage triggers sympathetically-mediated baroreflex responses to maintain organ perfusion; these reflexes are less sensitive in patients with orthostatic intolerance, and during conditions of severe blood loss, may result in cardiovascular collapse (decompensatory or circulatory shock). The ability to tolerate central hypovolemia is variable and physiological factors contributing to tolerance are emerging. We tested the hypothesis that resting muscle sympathetic nerve activity (MSNA) and sympathetic baroreflex sensitivity (BRS) are attenuated in male and female subjects who have low tolerance (LT) to central hypovolemia induced by lower body negative pressure (LBNP). MSNA and diastolic arterial pressure (DAP) were recorded in 47 human subjects who subsequently underwent LBNP to tolerance (onset of presyncopal symptoms). LT subjects experienced presyncopal symptoms prior to completing LBNP of 60mm Hg, and subjects with high tolerance (HT) experienced presyncopal symptoms after completing LBNP of 60mm Hg. Contrary to our hypothesis, resting MSNA burst incidence was not different between LT and HT subjects, and was not related to time to presyncope. BRS was assessed as the slope of the relationship between spontaneous fluctuations in DAP and MSNA during 5 min of supine rest. MSNA burst incidence/DAP correlations were greater than or equal to 0.5 in 37 subjects (LT: n = 9; HT: n = 28), and BRS was not different between LT and HT ( 1.8 0.3 vs. 2.2 0.2 bursts (100 beats) 1 mm Hg 1, p = 0.29). We conclude that tolerance to central hypovolemia is not related to either resting MSNA or sympathetic BRS., Published in Frontiers in Physiology, v5 article 241, Jun 2014. Prepared in collaboration with the University of North Texas Health Science Center, Fort Worth.

The studies examined mechanism based therapies to prevent or treat noise induced tinnitus. Our studies showed a military relevant small arms fire-like noise will induce tinnitus in approximately 33% of exposed rats. There is increasing evidence that noise induced loss of connections between sensory cells and the auditory nerve can induce tinnitus. Studies therefore examined if anti-oxidant and or anti-excitotoxicity therapy could decrease the loss of these connections from the small arms fire-like noise and if so, prevent tinnitus. Results first showed that a combination of Piribedil and Memantine (anti-excitoxicity) plus Vitamins A, C and E plus magnesium (anti-oxidants) provided protection, with significantly reduced loss of connections. Studies next tested if this treatment would then reduce tinnitus. The results showed decreased incidence of tinnitus following noise in the group receiving this combined treatment prior to the noise compared to groups of noise exposed animals without treatment. The next set of studies targeted the auditory brain stem and treatment rather than prevention. Studies tested treatment with sarcosine, which increases inhibitory influence by decreasing uptake of glycine from synapses. The studies found that sarsosine given shortly after the noise exposure or shortly before the noise did not influence the incidence of tinnitus. However, sarcosine when provided over a 4 - 6 week period following the noise showed a trend towards inducing recovery in animals that developed tinnitus. Future studies will be needed to follow up on this finding., The original document contains color images.

The overarching objective of this study was to characterize abnormalities of vestibulo-ocular reflexes in Autism Spectrum Disorder (ASD). Specific Aim 1: To characterize aberrations in horizontal VOR post-rotary nystagmus without optokinetic feedback using a velocity step test. We hypothesize that in ASD vertical eye movement intrusions during horizontal nystagmus will occur more frequently than normal, will be time-locked to horizontal nystagmus, and will differ from voluntary saccades. Specific Aim 2: To apply a linear systems analysis based method for testing horizontal VOR without optokinetic feedback using sinusoidal oscillation tests. We hypothesize that gain and phase lag of horizontal VOR will differ in children with ASD compared to controls. Specific Aim 3: To characterize in ASD vertical VOR and torsional VOR, both without optokinetic feedback, using velocity step tests., The original document contains color images.

A sensitive measure of the middle-ear muscle reflex (MEMR) is needed when making other sensitive audiological tests where activating the MEMR could confound and confuse test results. In this report we document and describe three related methods for making this sensitive MEMR measurement using the OAE and MOCR measurement modules in the Mimosa Acoustics HearID system. All three methods can sensitively detect small MEMR; however, for many ears, test variability is too high to make a clear determination of MEMR threshold., The original document contains color images.

Spatial disorientation (SD) is a deadly threat to aviation safety, so it is important to train pilots to recognize, avoid, and/or recover from it. Flight simulation is a safe and relatively inexpensive vehicle for SD training, but certain simulator characteristics, such as the field of view (FOV) required for effective training, need to be better specified. These specifications then need to be applied in upgrades to simulators used in SD training. This project examined three different FOVs and their ability to induce specific responses associated with SD, namely the Opto Kinetic Cervical Reflex (OKCR) and Control Reversal Error (CRE). Twelve pilots flew a simulator in two different scenarios using a Small, Medium, and Large FOV. The results indicated that under these conditions the Medium FOV was an optimum choice for eliciting the OKCR and CREs, since it generally outperformed the Small FOV and equaled the Large FOV, all at a lower price point and with a smaller footprint. This information is being directly applied to the Advanced SD Training simulator acquisition process that is currently underway at NAVAIR PMA-205, Aviation Training Systems. The results are applicable to other simulator systems as well, and implications and recommendations for SD training are discussed.

This report contains a transcript of the invited lectures comprising day 1 of a Spatial Orientation Symposium in honor of Dr. Frederick Guedry, held at the Institute of Human and Machine Cognition (IHMC) in Pensacola, FL on 19-20 November 2010. The conference was sponsored by the Coalition Warfare Program of the Office of the Under Secretary of Defense for Acquisition, Technology, and Logistics. It was organized by Drs. Angus Rupert and Ben Lawson (USAARL) and Drs. Anil Raj and Ken Ford (IHMC). This report opens with the transcript of a speech by Dr. Rupert, who provides some little-known facts about Fred Guedry and gives an overview of the topics and speakers. The subsequent lectures by Drs. Laurence Young, Charles Oman, Jan Holly, Braden McGrath, Wallace Grant, and Ian Curthoys focus on the modeling and neuroscience of vestibular structure, function, reflexes, and orientation perceptions., The original document contains color images.

Syftet med detta utvecklingsarbete var att utveckla en lärarahandledning som stöd i teknik riktat till pedagoger i förskolan. Den skullle ge barnen en möjlighet till att skapa ett intresse för teknik. Lärarhandledningen riktar sig till pedagoger som arbetar med barn i åldrarna 3-6 och innehåller frågor om tekniken i vardagen som kan ställas av två mjukbjörnar, Nelli och Nalle. Utifrån dessa frågor så framställdes konkreta bygg- och konstruktionsuppdrag till varje enskild fråga. I handledningen så beskrivs det på vilket sätt pedagogerna kan arbeta med frågorna. Handledningen har utvärderats av fyra förskollärare och fick mycket positiv respons., The aim of this development work was to develop a teacher´s guide to assist in technology aimed at educators in preschool. It would give the kids an opportunity to create an interest in the technology. Teacher´s Guide is aimed at educators that works with children ages 3-6 and includes questions about the technology of every day life that can be aked of two softbears, Nelli and Nalle. From these questions then prepared an constuction and constuction tasks to each individual question. The Guide describes the way in which teahers can work with technology in every day life. The tutorial has been evalueted in four preschool theacher´s and got a very positive respons.

Purpose: to test the whether photosensitivity (photophobia) after traumatic brain injury (TBI) is due to increased sensitivity of the brainstem trigeminal sensory nucleus, as revealed objectively by an exaggerated photoblink reflex (photo-electromyogram). This will be tested in humans and in a mouse strain genetically engineered to be hypersensitive to calcitonin gene related peptide (CGRP), the neurotransmitter modulating trigeminal nerve function. Scope: objective methods to quantify photo-sensitivity include 1) light evoked potentials (electromyogram) from the blinking and squinting muscles of the forehead 2) the pupil light reflex 3) light evoked changes in sympathetic nerve activity, measured by changes in skin conductance and heart rate. Major Findings (Year 2): 1) First successful recording from EMG electrodes implanted into the mouse orbicularis oculi muscle with wireless transmission of EMG in response to stimuli in an awake, unanesthetized mouse, 2) Observation of increased orbicularis EMG activity in response to increased light levels, 3) Observation of an apparent enhancement of an air puff induced blink by light after administration of an intraperitoneal injection of calcitonin gene related peptide (CGRP). Significance: objective testing of photosensitivity in humans and mice will provide new approaches to finding the underlying mechanisms, classification of photosensitivity, diagnosis and monitoring of new treatments., The original document contains color images.

Purpose: to develop and validate objective tests to diagnose vision deficits in patients with cognitive impairment and ensure effective monitoring of their treatment. Scope: objective methods to monitor visual function include 1) the pupil light reflex (PLR), 2) light evoked potentials (VEP) from the brain and from the eye and 3) purposeful eye movements to track moving targets that are resolved. Major Findings (year 3): i) development of an objective test protocol and data analysis routines to derive metrics that correlate with clinical diagnoses of afferent and efferent pathway pathologies based on the PLR. This protocol is less than 22 seconds in duration. The Pearson correlation coefficient between the derived continuous RAPD metric and clinical RAPD measurements is 0.86; ii) implementation and testing of a user interface to quickly and efficiently detect and remove artifacts from PLR data; iii) comparison of the design matrix method for VEP stimuli with the maximum length sequences (msequences) method based on simulations and various statistical metrics. Significance: objective tests of vision will greatly improve eye care by providing faster, lower cost testing that can be performed in remote settings and will provide a new tool for assessing innovative treatments being developed to save or restore vision., The original document contains color images.

We successfully developed and implemented a battery of visual tests designed to diagnose various visual dysfunctions by means of recording and objectively analyzing passive oculomotor reflexes. All hardware and software components of the data acquisition and analysis pipeline were finalized and tested in realistic experimental conditions on normal observers and several observers with visual dysfunctions. Observers received no instructions from us regarding their task except for attending to the screen. This passive viewing regime imitated experimental conditions for testing cognitively impaired patients. The project results indicate that the adopted paradigm has sufficient statistical power to successfully diagnose various visual dysfunctions, which validates the proposed approach., The original document contains color images.

Purpose: We are evaluating efficacy of GM6001, a matrix metalloproteinase (MMP) inhibitor in a murine model of spinal cord injury (UCSF) and in dogs (Texas A & M, TAMU) that sustain naturally occurring spinal cord injuries resulting from spontaneous intervertebral disk herniation (IVDH). Scope: These studies focus on efficacy of GM6001 in the context of an optimal therapeutic window and dependency on injury severity, using clinically relevant neurologic and urologic outcome measures. Major findings: -Spinal cord injury (SCI) in mice resulted in marked injury severity-dependent changes in locomotor and bladder function. - GM6001 has an extended therapeutic window. When given up to at least 8 hours post injury, GM6001 resulted in injury severity dependent efficacy in a murine model of SCI. GM6001 treatment resulted in both neurologic and urologic benefit after a moderate level of SCI and was associated with a decrease in lesion volume and greater spared white matter volume. In contrast, GM6001 did not rescue locomotor or bladder function in mice with severe SCIs. - Pharmacokinetic study of GM6001 in 10 dogs supports the short-term safety of the drug. Plasma drug levels following a single dose are sustained at a significant level likely to result in MMP inhibition for approximately 72 hours, which support a single dose strategy in the clinical trial. -Developed cystometry protocol on 10 uninjured dogs. -Enrolled 17 dogs with acute IVDH-associated SCI into serial cystometry study. Dogs with SCI that are nonambulatory lack normal voiding reflex, have larger bladder capacity, elevated post-cystometry baseline pressure, and larger residual volume compared to measures taken during recovery. Significance: We have found that GM6001 is efficacious when the therapeutic window is extended up to at least 8 hours after SCI of moderate severity. However, a similar benefit is not seen after a more severe SCI., The original document contains color images.

There are 300,000 individuals in the United States with spinal cord injury (SCI), where 22% are veterans [1,2]. While their quality of life is significantly affected by lower urinary tract symptoms (LUTS), most treatments are palliative or ineffective. We focused on the therapeutic benefits of 3 adrenoceptor agonists, botulinum neurotoxin type A (BTX-A) intradetrusor injections and their combination. BTX-A inhibits neurotransmitter release from nerve terminals. This has therapeutic effects on bladder dysfunction by inhibiting parasympathetic nerves to decrease reflex contractions, and afferent nerves, to reduce sensory symptoms. However, by also inhibiting sympathetic nerves, BTX-A decreases norepinephrine release and stimulation of detrusor 3 adrenoceptors thereby decreasing relaxation and bladder compliance. Accordingly, we assessed the effects of BTX-A and 3 adrenoceptor agonists in combination. In control mice, 3 agonists had little effect as 3 adrenoceptors are not normally expressed in mice. In SCI mice, 3 agonists were beneficial by abolishing intrinsic bladder contractions and enhancing bladder compliance suggesting that 3 adrenoceptors are upregulated in pathology. In BTX-A treated SCI mice, 3 agonists significantly improved bladder compliance compromised by the toxin. Thus, 3 adrenoceptor agonists in combination with BTX-A are beneficial in improving bladder function in SCI patients., The original document contains color images.

Mild traumatic brain injury (mTBI), such as mild blast injuries due to improvised exploding devices, result in long term impairment of cognition and behavior. Our hypothesis is that there are inflammatory outcomes to mTBI over time that cause pathogenesis and clinical outcomes. We used an adaptation of rat moderate brain lateral fluid percussion (LFP) brain injury and compared 2 blast models developed by us. We characterized a rat mild blast brain injury model (mBBI) that increased IL- 1 beta and TNF alpha levels, macrophage/microglial and astrocytic activation, and blood brain barrier disruption. We assessed beneficial outcomes after blockade of the IL-1alpha/beta and TNF alpha receptors in the mLFP brain injury model. We found that blocking the IL-1 /beta and TNFR receptors, singly or in combination, with wo FDA-approved drugs (Kineret or Interleukin-1 Receptor Antagonist, IL-1R alpha and Etanercept or antibody to the Tumor Necrosis Factor Receptor improved outcomes by ameliorating inflammation. We also determined an optimal time course of treatment. We also characterized our selected mBBI model of mTBI, the Vanderberg model. We found similar resulting righting reflex response times (RRRT) for the mBBI as compared to the mLFP injury. We determined that there were significant increases in IL-1 beta and TNF alpha levels, macrophage/microglial and astrocytic activation, and phosphorylated Tau (p-Tau) levels, the latter indicative of neuroencephalopathy, in the injured cortex, hippocampus, thalamus and amygdala. Whereas there was an apparent correlation between the RRRT values and the p-Tau levels, general inflammatory responses were more threshold-triggered. These results suggest potential therapies for mild blast injuries., The original document contains color images.

The overarching objective of this study is to characterize abnormalities of vestibulo-ocular reflexes (VOR) in Autism Spectrum Disorder (ASD). Specific Aim 1: Characterize horizontal VOR post-rotary nystagmus without optokinetic feedback using a velocity step test. We hypothesize that in ASD vertical eye movement intrusions during horizontal nystagmus will occur more frequently than normal, will be time-locked to horizontal nystagmus, and will differ from voluntary saccades. Specific Aim 2: Characterize horizontal VOR without optokinetic feedback using sinusoidal oscillation tests. We hypothesize that gain and phase lag of horizontal VOR will differ in children with ASD compared to controls. Specific Aim 3: Characterize in ASD vertical VOR and torsional VOR, both without optokinetic feedback. The present report covers the second year following award initiation. Complete research data have been obtained from 16 children with ASD and 36 typically developing children., The original document contains color images.

HMDs and their integration into military systems have greatly improved. However, a significant issue with HMDs is the effect of vibration and the Vestibulo-Ocular Reflex (VOR). When a human's head is subject to low-frequency vibration, the VOR stabilizes the eye with respect to the external environment. However this response causes blurring of an HMD display as the system moves with the user's head. This research sought to understand the VOR as a function of whole body low-frequency vibration. An experimental HMD was developed to allow a user to perform visual tasks, while also recording eye movements via video recording and EOG. A human subject experiment was executed to collect data on vibration effects on eye movement while performing tasks chosen to isolate specific eye motions. The results indicate that during fixation on a stationary target, the magnitude of eye movement was greatest at 4-6 Hz. The addition of motion to this target significantly increased the magnitude at this range. The findings are consistent with previous research which has found a decline in visual performance at 4-6 Hz., The original document contains color images.

Background: Vibration is known to alter proprioceptive afferents and create a tonic vibration reflex. The control of force and its variability are often considered determinants of motor performance and neuromuscular control. However, the effect of vibration on paraspinal muscle control and force production remains to be determined. Methods: Twenty-one healthy adults were asked to perform isometric trunk flexion and extension torque at 60% of their maximal voluntary isometric contraction, under three different vibration conditions: no vibration, vibration frequencies of 30 Hz and 80 Hz. Eighteen isometric contractions were performed under each condition without any feedback. Mechanical vibrations were applied bilaterally over the lumbar erector spinae muscles while participants were in neutral standing position. Time to peak torque (TPT), variable error (VE) as well as constant error (CE) and absolute error (AE) in peak torque were calculated and compared between conditions. Results: The main finding suggests that erector spinae muscle vibration significantly decreases the accuracy in a trunk extension isometric force reproduction task. There was no difference between both vibration frequencies with regard to force production parameters. Antagonist muscles do not seem to be directly affected by vibration stimulation when performing a trunk isometric task. Conclusions: The results suggest that acute erector spinae muscle vibration interferes with torque generation sequence of the trunk by distorting proprioceptive information in healthy participants.

Pupillary light reflex (PLR) refers to the involuntary response whereby the pupil size changes in response to a short flash light. In this project, we will evaluate the atypical dynamic pupillary light reflex (PLR) observed in children autism. In addition, we will develop an integrated PLR fMRI protocol for imaging PLR associated brain activities. At the end of the 2nd project year, we have tested pupillary light reflex (PLR) and heart rate variability (HRV) in 304 participants including 152 children with ASD (the ASD group), 116 children of typical development (the TD group), and 36 children with other development disorders (the NDD group). The results showed that the ASD group had significantly longer PLR latency, reduced relative constriction amplitude, and lesser constriction/redilation time than those of the TD group. Similar atypical PLR parameters were observed in the NDD group. A significant age effect on PLR latency was observed in children younger than 9 years in the TD group, but not in the ASD and NDD groups. Atypical HRV parameters were observed in the ASD and NDD groups. A significant negative correlation existed between the PLR constriction amplitude and average heart rate in children with an ASD, but not in children with typical development. We also developed an integrated fMRI/PLR protocol and have obtained fMRI data for 25 adolescents with ASD and 25 typically developing adolescents without ASD., The original document contains color images.

Purpose: to develop and validate objective tests to diagnose vision deficits in patients with cognitive impairment and ensure effective monitoring of treatment. Scope: objective methods to monitor vision include 1) the pupil light reflex, 2) light evoked potentials from the brain and from the eye and 3) purposeful eye movements to track moving targets that are resolved. Major Findings (year two): 1) a prototype, dry electrode system was delivered in Year 2 and was evaluated with specified requirements met, 2) a Smart Eye head and ocular tracking system was further tested and optimized in conjunction with a high contrast, high luminance 55 monitor for presenting visual stimuli for eye movement, pupil responses and cortical visual evoked potentials (VEPs), 3) a software architecture (matrix approach) for regional visual field stimulus presentation, data synchronization, and analysis from visual cortical responses recorded from scalp electrodes was developed and completed. Significance: objective tests of vision based on eye tracking of visual targets, pupil responses, and cortical visual evoked potentials will greatly improve eye care by providing faster, lower cost testing that can be performed in remote settings and will provide a new tool for assessing innovative treatments being developed to save or restore vision., The original document contains color images.

Purpose: to test the whether photosensitivity (photophobia) after traumatic brain injury (TBI) is due to increased sensitivity of the brainstem trigeminal sensory nucleus, as revealed objectively by an exaggerated photoblink reflex (photo-electromyogram). This will be tested in humans and in a mouse strain genetically engineered to be hypersensitive to calcitonin gene related peptide (CGRP), the neurotransmitter modulating trigeminal nerve function. Scope: objective methods to quantify photo-sensitivity include 1) light evoked potentials (electromyogram) from the blinking and squinting muscles of the forehead 2) the pupil light reflex 3) light evoked changes in sympathetic nerve activity, measured by changes in skin conductance and heart rate. Major Findings (year one): 1) optimization of hardware and software interfaces for recording of the electromyogram (EMG) elicited by light, 2) development of software to simultaneously record and analyze light evoked changes in the EMG, skin conductance, heart rate, and pupil responses. 3) EMG recording from chronically implanted electrodes in the mouse orbicularis muscle was developed using the DSI wireless system of data transmission of biopotentials). Significance: objective testing of photosensitivity in humans and mice will provide new approaches to finding the underlying mechanisms, classification of photosensitivity, diagnosis and monitoring of new treatments., The original document contains color images.

This study is comprised of three trials, referred to as the Assessment of Chiropractic Treatment (or ACT). the most significant work during the last reporting period was the finalization of the protocol for ACT1 (RCT for low back pain and nested smoking cessation study) its movement into the military IRB process and the CRADA process, Further, protocols for Assessment of Chiropractic Trials study 2 (Pre/post differences in reflexes and reaction times in Special Operation Forces) and study 3 (RCT of strength, balance and likelihood of re-injury with combat ready troops, chiropractic manipulation therapy as compared to sham manipulation) have been finalized.

The overarching objective of this study is to characterize abnormalities of vestibulo-ocular reflexes (VOR) in Autism Spectrum Disorder (ASD). Specific aim 1: Characterize horizontal VOR post-rotary nystagmus without optokinetic feedback using a velocity step test. We hypothesize that in ASD vertical eye movement intrusions during horizontal nystagmus will occur more frequently than normal, will be time-locked to horizontal nystagmus, and will differ from voluntary saccades. Specific aim 2: Characterize horizontal VOR without optokinetic feedback using sinusoidal oscillation tests. We hypothesize that gain and phase lag of horizontal VOR will differ in children with ASD compared to controls. Specific aim 3: Characterize in ASD vertical VOR and torsional VOR, both without optokinetic feedback. The present report covers the second year following award initiation. Complete research data have been obtained from one child with ASD and 18 typically developing children., The original document contains color images.

We significantly improved the battery of tests designed to diagnose various visual dysfunctions. All hardware and software components of data acquisition and analysis pipeline are in place now allowing data collection and analysis in real-time regime. The visual stimulation and data collection units were tested on 25 naive observers with normal vision and 2 observers with possible visual dysfunctions. We used the collected data to make a pilot comparison of oculomotor responses between normal subjects and subjects with visual dysfunctions. The results indicated that the adopted paradigm could be used for an automated detection of visual dysfunctions. This mostly completes the second phase of the project and allows us to start the last phase, which mainly focuses on the two goals: testing a large number of normal subjects to establish the distribution of responses for people with normal (reference) visual functions, and testing subjects with visual/cognitive dysfunctions to validate the proposed approach., The original document contains color images.

Besides the academic outputs produced during the period of funding and probably beyond one of the most important outcomes over the last couple of year has been a clear research agenda for this work. While collaborating with the groups of Graham Taylor and Sean Humbert this research has shaped into a system neuroscience approach that combines quantitative behavior, electrophysiology, functional anatomy and modeling to advance our understanding of biological control design with a strong emphasis on the underlying neuronal mechanisms. In particular the interactions with Sean Humbert have resulted in several tangible outputs, e.g. the proof of concept study showing that LPTC receptive fields can be successfully used to control orientation, proximity and forward speed of a quadropter (O35) or the development of an ocellar senor (C6). Future interactions between the group and the groups of collaborators will aim to further discover and exploit biological design principles in the context of control and navigation of autonomous robotic systems. The emphasis will be to advance autonomy and manoeuvrability by multisensor fusion, dynamic range fractioning and the integration of inner- and outer loop control., The original document contains color images.

This is the first annual report detailing work on the mechanosensory Boehm's bristles located on the base of the moth antennae that are responsible for mediating antennal positioning in the hawk moth Daphnis nerii. The report also outlines experiments to show how insect antennal muscles are also influenced by visual inputs., Sections: 1. Visual input to the antennal motor system of hawk moths (Anand Krishnan); 2. Neural mechanisms of flight control in moths (Umesh Mohan, Sunil Prabhakar) and 3. Antennal responses to airflow in flying honey bees: (Taruni Roy)

Understanding when operators are experiencing high workload is important in the design and implementation of Command, Control, Communications, Computers, Intelligence, Surveillance and Reconnaissance (C4ISR) systems. Fortunately physiological metrics, such as pupillary reflexes, have been shown to correlate with increases in mental workload. This paper proposes an automated method for characterizing and identifying task evoked pupillary responses (TEPR) during various workload levels. This method captures findings and observations from previous TEPR studies in an automated algorithm. This algorithm characterizes the rate of pupil dilation and constriction into a TEPR area metric, which is then used to identify times of increased operator workload. Independent trial analysis shows the benefits of using the TEPR area for distinguishing different workload responses but additional investigation is needed to make the algorithm more robust to individual variability., Proceedings of the Annual Meeting of the Human Factors & Ergonomics Society, Las Vegas, NV, 19-23 Sep 2011.

The overarching objective of this study is to characterize abnormalities of vestibulo-ocular reflexes (VOR) in Autism Spectrum Disorder (ASD). Specific Aim 1: Characterize horizontal VOR post-rotary nystagmus without optokinetic feedback using a velocity step test. We hypothesize that in ASD vertical eye movement intrusions during horizontal nystagmus will occur more frequently than normal, will be time-locked to horizontal nystagmus, and will differ from voluntary saccades. Specific Aim 2: Characterize horizontal VOR without optokinetic feedback using sinusoidal oscillation tests. We hypothesize that gain and phase lag of horizontal VOR will differ in children with ASD compared to controls. Specific Aim 3: Characterize in ASD vertical VOR and torsional VOR, both without optokinetic feedback. Because neither of these aspects of the VOR have been described previously in ASD, Aim 3 is exploratory., The original document contains color images.

We successfully developed and implemented a pilot battery of tests designed to diagnose various visual dysfunctions. The principal hardware and software components of data acquisition and analysis pipeline are in place now. The visual stimulation and data collection units were tested on 26 naive observers with normal vision. We used the collected data to design software filters for automatic detection of oculomotor reflexes. These results mostly complete the first phase of the project and allow us to start the next phase, which focuses on two goals: making the developed battery of visual tests adaptive, and testing a large number of normal subjects to establish the distribution of responses for people with normal (reference) visual functions., The original document contains color images.

The purpose of this study is to develop a survival model of blast-induced traumatic brain injury (BI-TBI) in swine. Two air guns were constructed, each having different lengths, air chamber volumes and barrel diameters. Air velocity was measured with a ballistics chronometer over a series of firings at different blast pressures. Calibration curves show linear and reproducible results through a range of firing pressures. Under anesthesia swine received BI-TBI with either one of the air guns at two different pressures and recovered for 7 days. Swine injured with the larger gun at the higher pressure took longer to return to normal behavior compared to the control or lesser blast animals. These animals demonstrated circling behavior, un-coordination, increased startle reflex, and hyperactivity during the recovery period. In a novel object test these injured animals took longer to start to investigate and the object was novel for a longer time. They showed electrocardiogram changes on Day 7 post blast indicating coronary ischemia and injury. The results show that this swine model of blast induced traumatic brain injury will provide a needed tool for the development of treatment for traumatic head injuries, rehabilitation and improvements in military and civilian protective body., The original document contains color images.

The shared-representation model of empathy suggests that vicarious pain processes rely partly on the activation of brain systems underlying self-pain in the observer. Here, we tested the hypothesis that self-pain may be facilitated by the vicarious priming of neural systems underlying pain perception. Pictures illustrating painful agents applied to the hand or the foot (sensory information), or painful facial expressions (emotional information) were shown to 43 participants to test the effects of vicarious pain on the nociceptive flexion reflex (NFR) of the lower limb and pain intensity and unpleasantness produced by transcutaneous electrical stimulation applied over the sural nerve. Results confirmed the expected priming effects of vicarious pain on spinal and perceptual processes. However, for comparable pain intensity and arousal evoked by the pain pictures, the facilitation of the NFR and the self-pain unpleasantness measurements was more robust in response to pictures depicting pain sensory compared to emotional information. Furthermore, the facilitation of the NFR by pain pictures was positively correlated with the empathy trait of the observer. In contrast, the change in perceived shock-pain intensity was negatively correlated with empathic traits. This dissociation implies that low-level vicarious priming processes underlying pain facilitation may be downregulated at higher pain-processing stages in individuals reporting higher levels of empathy. We speculate that this process contributes to reducing self–other assimilation and is necessary to adopt higher-order empathic responses and altruistic behaviors.

Endpoint stiffness is known to increase in the direction of instability during learning to accurately execute unstable motor tasks. Reflexes might be present in the time interval used for endpoint stiffness calculations suggesting a possible influence of reflexes on endpoint stiffness measurements. In addition, changes of reflexes during motor learning are still unknown. The purpose of this research was to investigate the separate contributions of intrinsic and reflexive stiffness to the observed change in endpoint stiffness during learning to move the hand in unstable force fields. A divergent (unstable) force field (DF) was applied with a two degrees of freedom manipulator (ARMANDA). Subjects performed 100 point-to-point arm movements in a null field and 300 point-to-point arm movements in the divergent force field holding the manipulator with their right hand. In random (catch) trials a minimum jerk position perturbation was applied in the middle of the movement. Force and EMG responses to the perturbation were used to examine endpoint stiffness and reflexes. Endpoint stiffness is defined as the force response to the imposed perturbation (in the interval 160-200 ms after perturbation onset) divided by the position displacement. Unperturbed trials were analyzed to investigate the decrease of errors (deviations from the straight path between start and target) and changes of co-contraction with motor learning. We found that errors decreased in the first 150 movements in the DF and leveled off from then on. Intrinsic, reflexive and endpoint stiffness were rapidly increased before the 35th DF trial. No significant changes of the stiffness parameters were found after this first learning period. An additional investigation of reflex response timing showed variability in the reflex timing between subjects. Reflexes were seen to influence the endpoint stiffness measurements for some subjects. In case of other subjects reflexes were not present in the time interval used fo, BM, BioMechanical Engineering, Mechanical, Maritime and Materials Engineering