496 research outputs found

    Gamma Band Oscillation Response to Somatosensory Feedback Stimulation Schemes Constructed on Basis of Biphasic Neural Touch Representation

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    abstract: Prosthetic users abandon devices due to difficulties performing tasks without proper graded or interpretable feedback. The inability to adequately detect and correct error of the device leads to failure and frustration. In advanced prostheses, peripheral nerve stimulation can be used to deliver sensations, but standard schemes used in sensorized prosthetic systems induce percepts inconsistent with natural sensations, providing limited benefit. Recent uses of time varying stimulation strategies appear to produce more practical sensations, but without a clear path to pursue improvements. This dissertation examines the use of physiologically based stimulation strategies to elicit sensations that are more readily interpretable. A psychophysical experiment designed to investigate sensitivities to the discrimination of perturbation direction within precision grip suggests that perception is biomechanically referenced: increased sensitivities along the ulnar-radial axis align with potential anisotropic deformation of the finger pad, indicating somatosensation uses internal information rather than environmental. Contact-site and direction dependent deformation of the finger pad activates complimentary fast adapting and slow adapting mechanoreceptors, exhibiting parallel activity of the two associate temporal patterns: static and dynamic. The spectrum of temporal activity seen in somatosensory cortex can be explained by a combined representation of these distinct response dynamics, a phenomenon referred in this dissertation to “biphasic representation.” In a reach-to-precision-grasp task, neurons in somatosensory cortex were found to possess biphasic firing patterns in their responses to texture, orientation, and movement. Sensitivities seem to align with variable deformation and mechanoreceptor activity: movement and smooth texture responses align with potential fast adapting activation, non-movement and coarse texture responses align with potential increased slow adapting activation, and responses to orientation are conceptually consistent with coding of tangential load. Using evidence of biphasic representations’ association with perceptual priorities, gamma band phase locking is used to compare responses to peripheral nerve stimulation patterns and mechanical stimulation. Vibrotactile and punctate mechanical stimuli are used to represent the practical and impractical percepts commonly observed in peripheral nerve stimulation feedback. Standard patterns of constant parameters closely mimic impractical vibrotactile stimulation while biphasic patterns better mimic punctate stimulation and provide a platform to investigate intragrip dynamics representing contextual activation.Dissertation/ThesisDoctoral Dissertation Biomedical Engineering 201

    Auditory associative learning and its neural correlates in the auditory midbrain

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    Interpreting the meaning of environmental stimuli to generate optimal behavioral responses is essential for survival. Simply sensing a sound, without accessing prior knowledge in the brain, will not benefit behavior. How sensation and memory interact to form behavior is one of the fundamental questions in the field of neuroscience. In this thesis, I have addressed this question from two perspectives: I investigated the behavioral outcome of this interaction using discrimination, and the circuit underlying this interaction using electrophysiological recordings in the behaving mouse. Behaviorally, we found that the physical difference between to-be-discriminated sounds, had a constraining effect on discrimination. This effect occurred even though physical differences were significantly larger than reported discrimination limens, thus reflecting a high overlap between the memory traces of the relevant stimuli. The results suggest a strong role of pre-wired tonotopic organization and the involvement of peripheral stations with wider tuning (Ehret and Merzenich, 1985; Taberner and Liberman, 2005). To further understand the influence of sensation on behavior, we tested the interaction between sound features with generalization. Using sounds that differed in two dimensions, we found that bi-dimensional generalization can be either biased towards a single dimension or an integration of both. Whether it was one or the other depended on the two dimensions used. As the first convergence station in the auditory system (Casseday et al., 2002), the role of the inferior colliculus in encoding behavioral relevant information is not well understood. Recording from freely behaving mouse, we found task engagement modulated neural activity in the IC in a stimulus-specific manner. Our lab found previously that relevant sound exposure induced enhancement in neural activity and shifts in tonal representation in the IC (Cruces-Solís et al., 2018). As a continuation, we found that movement-sound association is essential for this plasticity. Furthermore, recording in freely behaving mice also found that this association modulated the ongoing LFP in the IC, suggesting a new role of IC in filtering movement-related acoustic stimuli. To conclude, our results support the view that the IC is not simply an auditory structure that relays auditory information into the cortex, but plays important role in interpreting the meaning of the sound. The new role of IC in encoding movement-related information suggests that the filtering function of the auditory system starts already in subcortical stages of the auditory pathway

    Wearable and Nearable Biosensors and Systems for Healthcare

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    Biosensors and systems in the form of wearables and “nearables” (i.e., everyday sensorized objects with transmitting capabilities such as smartphones) are rapidly evolving for use in healthcare. Unlike conventional approaches, these technologies can enable seamless or on-demand physiological monitoring, anytime and anywhere. Such monitoring can help transform healthcare from the current reactive, one-size-fits-all, hospital-centered approach into a future proactive, personalized, decentralized structure. Wearable and nearable biosensors and systems have been made possible through integrated innovations in sensor design, electronics, data transmission, power management, and signal processing. Although much progress has been made in this field, many open challenges for the scientific community remain, especially for those applications requiring high accuracy. This book contains the 12 papers that constituted a recent Special Issue of Sensors sharing the same title. The aim of the initiative was to provide a collection of state-of-the-art investigations on wearables and nearables, in order to stimulate technological advances and the use of the technology to benefit healthcare. The topics covered by the book offer both depth and breadth pertaining to wearable and nearable technology. They include new biosensors and data transmission techniques, studies on accelerometers, signal processing, and cardiovascular monitoring, clinical applications, and validation of commercial devices

    生得的防御行動の分子、神経についての研究

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    筑波大学 (University of Tsukuba)201

    Electronic/electric technology benefits study

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    The benefits and payoffs of advanced electronic/electric technologies were investigated for three types of aircraft. The technologies, evaluated in each of the three airplanes, included advanced flight controls, advanced secondary power, advanced avionic complements, new cockpit displays, and advanced air traffic control techniques. For the advanced flight controls, the near term considered relaxed static stability (RSS) with mechanical backup. The far term considered an advanced fly by wire system for a longitudinally unstable airplane. In the case of the secondary power systems, trades were made in two steps: in the near term, engine bleed was eliminated; in the far term bleed air, air plus hydraulics were eliminated. Using three commercial aircraft, in the 150, 350, and 700 passenger range, the technology value and pay-offs were quantified, with emphasis on the fiscal benefits. Weight reductions deriving from fuel saving and other system improvements were identified and the weight savings were cycled for their impact on TOGW (takeoff gross weight) and upon the performance of the airframes/engines. Maintenance, reliability, and logistic support were the other criteria

    Mitigating User Frustration through Adaptive Feedback based on Human-Automation Etiquette Strategies

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    The objective of this study is to investigate the effects of feedback and user frustration in human-computer interaction (HCI) and examine how to mitigate user frustration through feedback based on human-automation etiquette strategies. User frustration in HCI indicates a negative feeling that occurs when efforts to achieve a goal are impeded. User frustration impacts not only the communication with the computer itself, but also productivity, learning, and cognitive workload. Affect-aware systems have been studied to recognize user emotions and respond in different ways. Affect-aware systems need to be adaptive systems that change their behavior depending on users’ emotions. Adaptive systems have four categories of adaptations. Previous research has focused on primarily function allocation and to a lesser extent information content and task scheduling. However, the fourth approach, changing the interaction styles is the least explored because of the interplay of human factors considerations. Three interlinked studies were conducted to investigate the consequences of user frustration and explore mitigation techniques. Study 1 showed that delayed feedback from the system led to higher user frustration, anger, cognitive workload, and physiological arousal. In addition, delayed feedback decreased task performance and system usability in a human-robot interaction (HRI) context. Study 2 evaluated a possible approach of mitigating user frustration by applying human-human etiquette strategies in a tutoring context. The results of Study 2 showed that changing etiquette strategies led to changes in performance, motivation, confidence, and satisfaction. The most effective etiquette strategies changed when users were frustrated. Based on these results, an adaptive tutoring system prototype was developed and evaluated in Study 3. By utilizing a rule set derived from Study 2, the tutor was able to use different automation etiquette strategies to target and improve motivation, confidence, satisfaction, and performance using different strategies, under different levels of user frustration. This work establishes that changing the interaction style alone of a computer tutor can affect a user’s motivation, confidence, satisfaction, and performance. Furthermore, the beneficial effect of changing etiquette strategies is greater when users are frustrated. This work provides a basis for future work to develop affect-aware adaptive systems to mitigate user frustration

    Algebraic Structures of Neutrosophic Triplets, Neutrosophic Duplets, or Neutrosophic Multisets

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    Neutrosophy (1995) is a new branch of philosophy that studies triads of the form (, , ), where is an entity {i.e. element, concept, idea, theory, logical proposition, etc.}, is the opposite of , while is the neutral (or indeterminate) between them, i.e., neither nor .Based on neutrosophy, the neutrosophic triplets were founded, which have a similar form (x, neut(x), anti(x)), that satisfy several axioms, for each element x in a given set.This collective book presents original research papers by many neutrosophic researchers from around the world, that report on the state-of-the-art and recent advancements of neutrosophic triplets, neutrosophic duplets, neutrosophic multisets and their algebraic structures – that have been defined recently in 2016 but have gained interest from world researchers. Connections between classical algebraic structures and neutrosophic triplet / duplet / multiset structures are also studied. And numerous neutrosophic applications in various fields, such as: multi-criteria decision making, image segmentation, medical diagnosis, fault diagnosis, clustering data, neutrosophic probability, human resource management, strategic planning, forecasting model, multi-granulation, supplier selection problems, typhoon disaster evaluation, skin lesson detection, mining algorithm for big data analysis, etc

    Proceedings experiencing light 2009 : international conference on the effects of light on welbeing

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    Proceedings experiencing light 2009 : international conference on the effects of light on welbeing

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    no abstrac

    2022 Summer Experience Program Abstracts

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    The mission of the MD Anderson Summer Experience Program is to eliminate cancer, through training of high School, undergraduates and first year medical students to make a lasting impact on training the next generation of scientist and physicians through research and education. The MD Anderson Summer Experience is an umbrella program that comprises 18 summer academic programs at MD Anderson. The summer research program is an 8-10 week program that offers hands-on experience in biomedical, translational or clinical research. In this program, students are matched with a mentor from MD Anderson’s research or clinical faculty. Participants work alongside the mentor in a lab or clinic, on projects designed by faculty to reflect current research. Workshops and lectures provide opportunities to connect with faculty, residents, postdoctoral and clinical fellows, and other participants. Through the program, students assess goals related to careers in oncology research and patient care. The program culminates with a symposium in which participants present talks and posters on their research projects to peers and faculty.https://openworks.mdanderson.org/sumexp22/1061/thumbnail.jp
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