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Sample records for multisensory multifunctional nucleus

  1. Multisensory constraints on awareness.

    PubMed

    Deroy, Ophelia; Chen, Yi-Chuan; Spence, Charles

    2014-05-05

    Given that multiple senses are often stimulated at the same time, perceptual awareness is most likely to take place in multisensory situations. However, theories of awareness are based on studies and models established for a single sense (mostly vision). Here, we consider the methodological and theoretical challenges raised by taking a multisensory perspective on perceptual awareness. First, we consider how well tasks designed to study unisensory awareness perform when used in multisensory settings, stressing that studies using binocular rivalry, bistable figure perception, continuous flash suppression, the attentional blink, repetition blindness and backward masking can demonstrate multisensory influences on unisensory awareness, but fall short of tackling multisensory awareness directly. Studies interested in the latter phenomenon rely on a method of subjective contrast and can, at best, delineate conditions under which individuals report experiencing a multisensory object or two unisensory objects. As there is not a perfect match between these conditions and those in which multisensory integration and binding occur, the link between awareness and binding advocated for visual information processing needs to be revised for multisensory cases. These challenges point at the need to question the very idea of multisensory awareness.

  2. Principles of multisensory behavior.

    PubMed

    Otto, Thomas U; Dassy, Brice; Mamassian, Pascal

    2013-04-24

    The combined use of multisensory signals is often beneficial. Based on neuronal recordings in the superior colliculus of cats, three basic rules were formulated to describe the effectiveness of multisensory signals: the enhancement of neuronal responses to multisensory compared with unisensory signals is largest when signals occur at the same location ("spatial rule"), when signals are presented at the same time ("temporal rule"), and when signals are rather weak ("principle of inverse effectiveness"). These rules are also considered with respect to multisensory benefits as observed with behavioral measures, but do they capture these benefits best? To uncover the principles that rule benefits in multisensory behavior, we here investigated the classical redundant signal effect (RSE; i.e., the speedup of response times in multisensory compared with unisensory conditions) in humans. Based on theoretical considerations using probability summation, we derived two alternative principles to explain the effect. First, the "principle of congruent effectiveness" states that the benefit in multisensory behavior (here the speedup of response times) is largest when behavioral performance in corresponding unisensory conditions is similar. Second, the "variability rule" states that the benefit is largest when performance in corresponding unisensory conditions is unreliable. We then tested these predictions in two experiments, in which we manipulated the relative onset and the physical strength of distinct audiovisual signals. Our results, which are based on a systematic analysis of response time distributions, show that the RSE follows these principles very well, thereby providing compelling evidence in favor of probability summation as the underlying combination rule.

  3. Neglect: a multisensory deficit?

    PubMed

    Jacobs, Stéphane; Brozzoli, Claudio; Farnè, Alessandro

    2012-05-01

    Neglect is a neurological syndrome characterised by a lack of conscious perception of events localised in the contralesional side of space. Here, we consider the possible multisensory nature of this disorder, critically reviewing the literature devoted to multisensory manifestations and processing in neglect. Although its most striking manifestations have been observed in the visual domain, a number of studies demonstrate that neglect can affect virtually any sensory modality, in particular touch and audition. Furthermore, a few recent studies have reported a correlation in severity between visual and non-visual neglect-related deficits evaluated in the same patients, providing some preliminary support for a multisensory conception of neglect. Sensory stimulation and sensorimotor adaptation techniques, aimed at alleviating neglect, have also been shown to affect several sensory modalities, including some that were not directly affected by the intervention. Finally, in some cases neglect can bias multisensory interactions known to occur in healthy individuals, leading to abnormal behaviour or uncovering multisensory compensation mechanisms. This evidence, together with neurophysiological and neuroimaging data revealing the multisensory role played by the areas that are most commonly damaged in neglect patients, seems to speak in favour of neglect as a multisensory disorder. However, since most previous studies were not conducted with the specific purpose of systematically investigating the multisensory nature of neglect, we conclude that more research is needed to appropriately assess this question, and suggest some methodological guidelines that we hope will help clarify this issue. At present, the conception of neglect as a multisensory disorder remains a promising working hypothesis that may help define the pathophysiology of this syndrome.

  4. Multisensory flavor perception.

    PubMed

    Spence, Charles

    2015-03-26

    The perception of flavor is perhaps the most multisensory of our everyday experiences. The latest research by psychologists and cognitive neuroscientists increasingly reveals the complex multisensory interactions that give rise to the flavor experiences we all know and love, demonstrating how they rely on the integration of cues from all of the human senses. This Perspective explores the contributions of distinct senses to our perception of food and the growing realization that the same rules of multisensory integration that have been thoroughly explored in interactions between audition, vision, and touch may also explain the combination of the (admittedly harder to study) flavor senses. Academic advances are now spilling out into the real world, with chefs and food industry increasingly taking the latest scientific findings on board in their food design.

  5. Metacognition in Multisensory Perception.

    PubMed

    Deroy, Ophelia; Spence, Charles; Noppeney, Uta

    2016-10-01

    Metacognition - the ability to monitor one's own decisions and representations, their accuracy and uncertainty - is considered a hallmark of intelligent behavior. Little is known about metacognition in our natural multisensory environment. To form a coherent percept, the brain should integrate signals from a common cause but segregate those from independent causes. Multisensory perception thus relies on inferring the world's causal structure, raising new challenges for metacognition. We discuss the extent to which observers can monitor their uncertainties not only about their final integrated percept but also about the individual sensory signals and the world's causal structure. The latter causal metacognition highlights fundamental links between perception and other cognitive domains such as social and abstract reasoning.

  6. Parietal connectivity mediates multisensory facilitation.

    PubMed

    Brang, David; Taich, Zachary J; Hillyard, Steven A; Grabowecky, Marcia; Ramachandran, V S

    2013-09-01

    Our senses interact in daily life through multisensory integration, facilitating perceptual processes and behavioral responses. The neural mechanisms proposed to underlie this multisensory facilitation include anatomical connections directly linking early sensory areas, indirect connections to higher-order multisensory regions, as well as thalamic connections. Here we examine the relationship between white matter connectivity, as assessed with diffusion tensor imaging, and individual differences in multisensory facilitation and provide the first demonstration of a relationship between anatomical connectivity and multisensory processing in typically developed individuals. Using a whole-brain analysis and contrasting anatomical models of multisensory processing we found that increased connectivity between parietal regions and early sensory areas was associated with the facilitation of reaction times to multisensory (auditory-visual) stimuli. Furthermore, building on prior animal work suggesting the involvement of the superior colliculus in this process, using probabilistic tractography we determined that the strongest cortical projection area connected with the superior colliculus includes the region of connectivity implicated in our independent whole-brain analysis.

  7. Generalization of multisensory perceptual learning

    PubMed Central

    Powers III, Albert R.; Hillock-Dunn, Andrea; Wallace, Mark T.

    2016-01-01

    Life in a multisensory world requires the rapid and accurate integration of stimuli across the different senses. In this process, the temporal relationship between stimuli is critical in determining which stimuli share a common origin. Numerous studies have described a multisensory temporal binding window—the time window within which audiovisual stimuli are likely to be perceptually bound. In addition to characterizing this window’s size, recent work has shown it to be malleable, with the capacity for substantial narrowing following perceptual training. However, the generalization of these effects to other measures of perception is not known. This question was examined by characterizing the ability of training on a simultaneity judgment task to influence perception of the temporally-dependent sound-induced flash illusion (SIFI). Results do not demonstrate a change in performance on the SIFI itself following training. However, data do show an improved ability to discriminate rapidly-presented two-flash control conditions following training. Effects were specific to training and scaled with the degree of temporal window narrowing exhibited. Results do not support generalization of multisensory perceptual learning to other multisensory tasks. However, results do show that training results in improvements in visual temporal acuity, suggesting a generalization effect of multisensory training on unisensory abilities. PMID:27000988

  8. Generalization of multisensory perceptual learning.

    PubMed

    Powers Iii, Albert R; Hillock-Dunn, Andrea; Wallace, Mark T

    2016-03-22

    Life in a multisensory world requires the rapid and accurate integration of stimuli across the different senses. In this process, the temporal relationship between stimuli is critical in determining which stimuli share a common origin. Numerous studies have described a multisensory temporal binding window-the time window within which audiovisual stimuli are likely to be perceptually bound. In addition to characterizing this window's size, recent work has shown it to be malleable, with the capacity for substantial narrowing following perceptual training. However, the generalization of these effects to other measures of perception is not known. This question was examined by characterizing the ability of training on a simultaneity judgment task to influence perception of the temporally-dependent sound-induced flash illusion (SIFI). Results do not demonstrate a change in performance on the SIFI itself following training. However, data do show an improved ability to discriminate rapidly-presented two-flash control conditions following training. Effects were specific to training and scaled with the degree of temporal window narrowing exhibited. Results do not support generalization of multisensory perceptual learning to other multisensory tasks. However, results do show that training results in improvements in visual temporal acuity, suggesting a generalization effect of multisensory training on unisensory abilities.

  9. Early Experience & Multisensory Perceptual Narrowing

    PubMed Central

    Lewkowicz, David J.

    2014-01-01

    Perceptual narrowing is a reflection of early experience and contributes in key ways to perceptual and cognitive development. In general, findings have shown that unisensory perceptual sensitivity in early infancy is broadly tuned such that young infants respond to, and discriminate, native as well as non-native sensory inputs, whereas older infants only respond to native inputs. Recently, my colleagues and I discovered that perceptual narrowing occurs at the multisensory processing level as well. The present article reviews this new evidence and puts it in the larger context of multisensory perceptual development and the role that perceptual experience plays in it. Together, the evidence on unisensory and multisensory narrowing shows that early experience shapes the emergence of perceptual specialization and expertise. PMID:24435505

  10. Multifunctional nanocrystals

    DOEpatents

    Klimov, Victor I.; Hollingsworth, Jennifer A.; Crooker, Scott A.; Kim, Hyungrak

    2010-06-22

    Multifunctional nanocomposites are provided including a core of either a magnetic material or an inorganic semiconductor, and, a shell of either a magnetic material or an inorganic semiconductor, wherein the core and the shell are of differing materials, such multifunctional nanocomposites having multifunctional properties including magnetic properties from the magnetic material and optical properties from the inorganic semiconductor material. Various applications of such multifunctional nanocomposites are also provided.

  11. Multifunctional nanocrystals

    DOEpatents

    Klimov, Victor I.; Hollingsworth, Jennifer A.; Crooker, Scott A.; Kim, Hyungrak

    2007-08-28

    Multifunctional nanocomposites are provided including a core of either a magnetic material or an inorganic semiconductor, and, a shell of either a magnetic material or an inorganic semiconductor, wherein the core and the shell are of differing materials, such multifunctional nanocomposites having multifunctional properties including magnetic properties from the magnetic material and optical properties from the inorganic semiconductor material. Various applications of such multifunctional nanocomposites are also provided.

  12. A multisensory perspective of working memory

    PubMed Central

    Quak, Michel; London, Raquel Elea; Talsma, Durk

    2015-01-01

    Although our sensory experience is mostly multisensory in nature, research on working memory representations has focused mainly on examining the senses in isolation. Results from the multisensory processing literature make it clear that the senses interact on a more intimate manner than previously assumed. These interactions raise questions regarding the manner in which multisensory information is maintained in working memory. We discuss the current status of research on multisensory processing and the implications of these findings on our theoretical understanding of working memory. To do so, we focus on reviewing working memory research conducted from a multisensory perspective, and discuss the relation between working memory, attention, and multisensory processing in the context of the predictive coding framework. We argue that a multisensory approach to the study of working memory is indispensable to achieve a realistic understanding of how working memory processes maintain and manipulate information. PMID:25954176

  13. Multisensory integration mechanisms during aging

    PubMed Central

    Freiherr, Jessica; Lundström, Johan N.; Habel, Ute; Reetz, Kathrin

    2013-01-01

    The rapid demographical shift occurring in our society implies that understanding of healthy aging and age-related diseases is one of our major future challenges. Sensory impairments have an enormous impact on our lives and are closely linked to cognitive functioning. Due to the inherent complexity of sensory perceptions, we are commonly presented with a complex multisensory stimulation and the brain integrates the information from the individual sensory channels into a unique and holistic percept. The cerebral processes involved are essential for our perception of sensory stimuli and becomes especially important during the perception of emotional content. Despite ongoing deterioration of the individual sensory systems during aging, there is evidence for an increase in, or maintenance of, multisensory integration processing in aging individuals. Within this comprehensive literature review on multisensory integration we aim to highlight basic mechanisms and potential compensatory strategies the human brain utilizes to help maintain multisensory integration capabilities during healthy aging to facilitate a broader understanding of age-related pathological conditions. Further our goal was to identify where further research is needed. PMID:24379773

  14. Multisensory integration mechanisms during aging.

    PubMed

    Freiherr, Jessica; Lundström, Johan N; Habel, Ute; Reetz, Kathrin

    2013-12-13

    The rapid demographical shift occurring in our society implies that understanding of healthy aging and age-related diseases is one of our major future challenges. Sensory impairments have an enormous impact on our lives and are closely linked to cognitive functioning. Due to the inherent complexity of sensory perceptions, we are commonly presented with a complex multisensory stimulation and the brain integrates the information from the individual sensory channels into a unique and holistic percept. The cerebral processes involved are essential for our perception of sensory stimuli and becomes especially important during the perception of emotional content. Despite ongoing deterioration of the individual sensory systems during aging, there is evidence for an increase in, or maintenance of, multisensory integration processing in aging individuals. Within this comprehensive literature review on multisensory integration we aim to highlight basic mechanisms and potential compensatory strategies the human brain utilizes to help maintain multisensory integration capabilities during healthy aging to facilitate a broader understanding of age-related pathological conditions. Further our goal was to identify where further research is needed.

  15. Multisensory Stimulation in Stroke Rehabilitation

    PubMed Central

    Johansson, Barbro Birgitta

    2012-01-01

    The brain has a large capacity for automatic simultaneous processing and integration of sensory information. Combining information from different sensory modalities facilitates our ability to detect, discriminate, and recognize sensory stimuli, and learning is often optimal in a multisensory environment. Currently used multisensory stimulation methods in stroke rehabilitation include motor imagery, action observation, training with a mirror or in a virtual environment, and various kinds of music therapy. Non-invasive brain stimulation has showed promising preliminary results in aphasia and neglect. Patient heterogeneity and the interaction of age, gender, genes, and environment are discussed. Randomized controlled longitudinal trials starting earlier post-stroke are needed. The advance in brain network science and neuroimaging enabling longitudinal studies of structural and functional networks are likely to have an important impact on patient selection for specific interventions in future stroke rehabilitation. It is proposed that we should pay more attention to age, gender, and laterality in clinical studies. PMID:22509159

  16. Multisensory stimulation in stroke rehabilitation.

    PubMed

    Johansson, Barbro Birgitta

    2012-01-01

    The brain has a large capacity for automatic simultaneous processing and integration of sensory information. Combining information from different sensory modalities facilitates our ability to detect, discriminate, and recognize sensory stimuli, and learning is often optimal in a multisensory environment. Currently used multisensory stimulation methods in stroke rehabilitation include motor imagery, action observation, training with a mirror or in a virtual environment, and various kinds of music therapy. Non-invasive brain stimulation has showed promising preliminary results in aphasia and neglect. Patient heterogeneity and the interaction of age, gender, genes, and environment are discussed. Randomized controlled longitudinal trials starting earlier post-stroke are needed. The advance in brain network science and neuroimaging enabling longitudinal studies of structural and functional networks are likely to have an important impact on patient selection for specific interventions in future stroke rehabilitation. It is proposed that we should pay more attention to age, gender, and laterality in clinical studies.

  17. Predictive coding of multisensory timing

    PubMed Central

    Shi, Zhuanghua; Burr, David

    2016-01-01

    The sense of time is foundational for perception and action, yet it frequently departs significantly from physical time. In the paper we review recent progress on temporal contextual effects, multisensory temporal integration, temporal recalibration, and related computational models. We suggest that subjective time arises from minimizing prediction errors and adaptive recalibration, which can be unified in the framework of predictive coding, a framework rooted in Helmholtz’s ‘perception as inference’. PMID:27695705

  18. Multisensory Integration and Child Neurodevelopment

    PubMed Central

    Dionne-Dostie, Emmanuelle; Paquette, Natacha; Lassonde, Maryse; Gallagher, Anne

    2015-01-01

    A considerable number of cognitive processes depend on the integration of multisensory information. The brain integrates this information, providing a complete representation of our surrounding world and giving us the ability to react optimally to the environment. Infancy is a period of great changes in brain structure and function that are reflected by the increase of processing capacities of the developing child. However, it is unclear if the optimal use of multisensory information is present early in childhood or develops only later, with experience. The first part of this review has focused on the typical development of multisensory integration (MSI). We have described the two hypotheses on the developmental process of MSI in neurotypical infants and children, and have introduced MSI and its neuroanatomic correlates. The second section has discussed the neurodevelopmental trajectory of MSI in cognitively-challenged infants and children. A few studies have brought to light various difficulties to integrate sensory information in children with a neurodevelopmental disorder. Consequently, we have exposed certain possible neurophysiological relationships between MSI deficits and neurodevelopmental disorders, especially dyslexia and attention deficit disorder with/without hyperactivity. PMID:25679116

  19. Walking to a multisensory beat.

    PubMed

    Roy, Charlotte; Lagarde, Julien; Dotov, Dobromir; Dalla Bella, Simone

    2017-04-01

    Living in a complex and multisensory environment demands constant interaction between perception and action. In everyday life it is common to combine efficiently simultaneous signals coming from different modalities. There is evidence of a multisensory benefit in a variety of laboratory tasks (temporal judgement, reaction time tasks). It is less clear if this effect extends to ecological tasks, such as walking. Furthermore, benefits of multimodal stimulation are linked to temporal properties such as the temporal window of integration and temporal recalibration. These properties have been examined in tasks involving single, non-repeating stimulus presentations. Here we investigate the same temporal properties in the context of a rhythmic task, namely audio-tactile stimulation during walking. The effect of audio-tactile rhythmic cues on gait variability and the ability to synchronize to the cues was studied in young adults. Participants walked with rhythmic cues presented at different stimulus-onset asynchronies. We observed a multisensory benefit by comparing audio-tactile to unimodal stimulation. Moreover, both the temporal window of integration and temporal recalibration mediated the response to multimodal stimulation. In sum, rhythmic behaviours obey the same principles as temporal discrimination and detection behaviours and thus can also benefit from multimodal stimulation.

  20. Multi-Sensory Intervention Observational Research

    ERIC Educational Resources Information Center

    Thompson, Carla J.

    2011-01-01

    An observational research study based on sensory integration theory was conducted to examine the observed impact of student selected multi-sensory experiences within a multi-sensory intervention center relative to the sustained focus levels of students with special needs. A stratified random sample of 50 students with severe developmental…

  1. Multisensory Teaching of Basic Language Skills.

    ERIC Educational Resources Information Center

    Birsh, Judith R., Ed.

    This text on multisensory structured language education (MSLE) provides the foundation for MSLE and offers components of instruction and effective teaching strategies that teachers can put into practice for students with dyslexia and others struggling to learn to read, write, and spell. Chapters include: (1) "Multisensory Instruction" (Louisa C.…

  2. Multisensory attention training for treatment of tinnitus

    PubMed Central

    D. P., Spiegel; T., Linford; B., Thompson; M. A., Petoe; K., Kobayashi; C. M., Stinear; G. D., Searchfield

    2015-01-01

    Tinnitus is the conscious perception of sound with no physical sound source. Some models of tinnitus pathophysiology suggest that networks associated with attention, memory, distress and multisensory experience are involved in tinnitus perception. The aim of this study was to evaluate whether a multisensory attention training paradigm which used audio, visual, and somatosensory stimulation would reduce tinnitus. Eighteen participants with predominantly unilateral chronic tinnitus were randomized between two groups receiving 20 daily sessions of either integration (attempting to reduce salience to tinnitus by binding with multisensory stimuli) or attention diversion (multisensory stimuli opposite side to tinnitus) training. The training resulted in small but statistically significant reductions in Tinnitus Functional Index and Tinnitus Severity Numeric Scale scores and improved attentional abilities. No statistically significant improvements in tinnitus were found between the training groups. This study demonstrated that a short period of multisensory attention training reduced unilateral tinnitus, but directing attention toward or away from the tinnitus side did not differentiate this effect. PMID:26020589

  3. Multisensory attention training for treatment of tinnitus.

    PubMed

    Spiegel, D P; Linford, T; Thompson, B; Petoe, M A; Kobayashi, K; Stinear, C M; Searchfield, G D

    2015-05-28

    Tinnitus is the conscious perception of sound with no physical sound source. Some models of tinnitus pathophysiology suggest that networks associated with attention, memory, distress and multisensory experience are involved in tinnitus perception. The aim of this study was to evaluate whether a multisensory attention training paradigm which used audio, visual, and somatosensory stimulation would reduce tinnitus. Eighteen participants with predominantly unilateral chronic tinnitus were randomized between two groups receiving 20 daily sessions of either integration (attempting to reduce salience to tinnitus by binding with multisensory stimuli) or attention diversion (multisensory stimuli opposite side to tinnitus) training. The training resulted in small but statistically significant reductions in Tinnitus Functional Index and Tinnitus Severity Numeric Scale scores and improved attentional abilities. No statistically significant improvements in tinnitus were found between the training groups. This study demonstrated that a short period of multisensory attention training reduced unilateral tinnitus, but directing attention toward or away from the tinnitus side did not differentiate this effect.

  4. Multisensory integration is independent of perceived simultaneity.

    PubMed

    Harrar, Vanessa; Harris, Laurence R; Spence, Charles

    2017-03-01

    The importance of multisensory integration for perception and action has long been recognised. Integrating information from individual senses increases the chance of survival by reducing the variability in the incoming signals, thus allowing us to respond more rapidly. Reaction times (RTs) are fastest when the components of the multisensory signals are simultaneous. This response facilitation is traditionally attributed to multisensory integration. However, it is unclear if facilitation of RTs occurs when stimuli are perceived as synchronous or are actually physically synchronous. Repeated exposure to audiovisual asynchrony can change the delay at which multisensory stimuli are perceived as simultaneous, thus changing the delay at which the stimuli are integrated-perceptually. Here we set out to determine how such changes in multisensory integration for perception affect our ability to respond to multisensory events. If stimuli perceived as simultaneous were reacted to most rapidly, it would suggest a common system for multisensory integration for perception and action. If not, it would suggest separate systems. We measured RTs to auditory, visual, and audiovisual stimuli following exposure to audiovisual asynchrony. Exposure affected the variability of the unisensory RT distributions; in particular, the slowest RTs were either speed up or slowed down (in the direction predicted from shifts in perceived simultaneity). Additionally, the multisensory facilitation of RTs (beyond statistical summation) only occurred when audiovisual onsets were physically synchronous, rather than when they appeared simultaneous. We conclude that the perception of synchrony is therefore independent of multisensory integration and suggest a division between multisensory processes that are fast (automatic and unaffected by temporal adaptation) and those that are slow (perceptually driven and adaptable).

  5. Connectional parameters determine multisensory processing in a spiking network model of multisensory convergence.

    PubMed

    Lim, H K; Keniston, L P; Shin, J H; Allman, B L; Meredith, M A; Cios, K J

    2011-09-01

    For the brain to synthesize information from different sensory modalities, connections from different sensory systems must converge onto individual neurons. However, despite being the definitive, first step in the multisensory process, little is known about multisensory convergence at the neuronal level. This lack of knowledge may be due to the difficulty for biological experiments to manipulate and test the connectional parameters that define convergence. Therefore, the present study used a computational network of spiking neurons to measure the influence of convergence from two separate projection areas on the responses of neurons in a convergent area. Systematic changes in the proportion of extrinsic projections, the proportion of intrinsic connections, or the amount of local inhibitory contacts affected the multisensory properties of neurons in the convergent area by influencing (1) the proportion of multisensory neurons generated, (2) the proportion of neurons that generate integrated multisensory responses, and (3) the magnitude of multisensory integration. These simulations provide insight into the connectional parameters of convergence that contribute to the generation of populations of multisensory neurons in different neural regions as well as indicate that the simple effect of multisensory convergence is sufficient to generate multisensory properties like those of biological multisensory neurons.

  6. Visual learning in multisensory environments.

    PubMed

    Jacobs, Robert A; Shams, Ladan

    2010-04-01

    We study the claim that multisensory environments are useful for visual learning because nonvisual percepts can be processed to produce error signals that people can use to adapt their visual systems. This hypothesis is motivated by a Bayesian network framework. The framework is useful because it ties together three observations that have appeared in the literature: (a) signals from nonvisual modalities can "teach" the visual system; (b) signals from nonvisual modalities can facilitate learning in the visual system; and (c) visual signals can become associated with (or be predicted by) signals from nonvisual modalities. Experimental data consistent with each of these observations are reviewed.

  7. Altered multisensory temporal integration in obesity

    PubMed Central

    Scarpina, Federica; Migliorati, Daniele; Marzullo, Paolo; Mauro, Alessandro; Scacchi, Massimo; Costantini, Marcello

    2016-01-01

    Eating is a multisensory behavior. The act of placing food in the mouth provides us with a variety of sensory information, including gustatory, olfactory, somatosensory, visual, and auditory. Evidence suggests altered eating behavior in obesity. Nonetheless, multisensory integration in obesity has been scantily investigated so far. Starting from this gap in the literature, we seek to provide the first comprehensive investigation of multisensory integration in obesity. Twenty male obese participants and twenty male healthy-weight participants took part in the study aimed at describing the multisensory temporal binding window (TBW). The TBW is defined as the range of stimulus onset asynchrony in which multiple sensory inputs have a high probability of being integrated. To investigate possible multisensory temporal processing deficits in obesity, we investigated performance in two multisensory audiovisual temporal tasks, namely simultaneity judgment and temporal order judgment. Results showed a wider TBW in obese participants as compared to healthy-weight controls. This holds true for both the simultaneity judgment and the temporal order judgment tasks. An explanatory hypothesis would regard the effect of metabolic alterations and low-grade inflammatory state, clinically observed in obesity, on the temporal organization of brain ongoing activity, which one of the neural mechanisms enabling multisensory integration. PMID:27324727

  8. Multisensory maps in parietal cortex☆

    PubMed Central

    Sereno, Martin I; Huang, Ruey-Song

    2014-01-01

    Parietal cortex has long been known to be a site of sensorimotor integration. Recent findings in humans have shown that it is divided up into a number of small areas somewhat specialized for eye movements, reaching, and hand movements, but also face-related movements (avoidance, eating), lower body movements, and movements coordinating multiple body parts. The majority of these areas contain rough sensory (receptotopic) maps, including a substantial multisensory representation of the lower body and lower visual field immediately medial to face VIP. There is strong evidence for retinotopic remapping in LIP and face-centered remapping in VIP, and weaker evidence for hand-centered remapping. The larger size of the functionally distinct inferior parietal default mode network in humans compared to monkeys results in a superior and medial displacement of middle parietal areas (e.g., the saccade-related LIP's). Multisensory superior parietal areas located anterior to the angular gyrus such as AIP and VIP are less medially displaced relative to macaque monkeys, so that human LIP paradoxically ends up medial to human VIP. PMID:24492077

  9. Multisensory temporal integration in autism spectrum disorders.

    PubMed

    Stevenson, Ryan A; Siemann, Justin K; Schneider, Brittany C; Eberly, Haley E; Woynaroski, Tiffany G; Camarata, Stephen M; Wallace, Mark T

    2014-01-15

    The new DSM-5 diagnostic criteria for autism spectrum disorders (ASDs) include sensory disturbances in addition to the well-established language, communication, and social deficits. One sensory disturbance seen in ASD is an impaired ability to integrate multisensory information into a unified percept. This may arise from an underlying impairment in which individuals with ASD have difficulty perceiving the temporal relationship between cross-modal inputs, an important cue for multisensory integration. Such impairments in multisensory processing may cascade into higher-level deficits, impairing day-to-day functioning on tasks, such as speech perception. To investigate multisensory temporal processing deficits in ASD and their links to speech processing, the current study mapped performance on a number of multisensory temporal tasks (with both simple and complex stimuli) onto the ability of individuals with ASD to perceptually bind audiovisual speech signals. High-functioning children with ASD were compared with a group of typically developing children. Performance on the multisensory temporal tasks varied with stimulus complexity for both groups; less precise temporal processing was observed with increasing stimulus complexity. Notably, individuals with ASD showed a speech-specific deficit in multisensory temporal processing. Most importantly, the strength of perceptual binding of audiovisual speech observed in individuals with ASD was strongly related to their low-level multisensory temporal processing abilities. Collectively, the results represent the first to illustrate links between multisensory temporal function and speech processing in ASD, strongly suggesting that deficits in low-level sensory processing may cascade into higher-order domains, such as language and communication.

  10. Impact of response duration on multisensory integration.

    PubMed

    Ghose, Dipanwita; Barnett, Zachary P; Wallace, Mark T

    2012-11-01

    Multisensory neurons in the superior colliculus (SC) have been shown to have large receptive fields that are heterogeneous in nature. These neurons have the capacity to integrate their different sensory inputs, a process that has been shown to depend on the physical characteristics of the stimuli that are combined (i.e., spatial and temporal relationship and relative effectiveness). Recent work has highlighted the interdependence of these factors in driving multisensory integration, adding a layer of complexity to our understanding of multisensory processes. In the present study our goal was to add to this understanding by characterizing how stimulus location impacts the temporal dynamics of multisensory responses in cat SC neurons. The results illustrate that locations within the spatial receptive fields (SRFs) of these neurons can be divided into those showing short-duration responses and long-duration response profiles. Most importantly, discharge duration appears to be a good determinant of multisensory integration, such that short-duration responses are typically associated with a high magnitude of multisensory integration (i.e., superadditive responses) while long-duration responses are typically associated with low integrative capacity. These results further reinforce the complexity of the integrative features of SC neurons and show that the large SRFs of these neurons are characterized by vastly differing temporal dynamics, dynamics that strongly shape the integrative capacity of these neurons.

  11. Multi-sensory integration in brainstem and auditory cortex.

    PubMed

    Basura, Gregory J; Koehler, Seth D; Shore, Susan E

    2012-11-16

    Tinnitus is the perception of sound in the absence of a physical sound stimulus. It is thought to arise from aberrant neural activity within central auditory pathways that may be influenced by multiple brain centers, including the somatosensory system. Auditory-somatosensory (bimodal) integration occurs in the dorsal cochlear nucleus (DCN), where electrical activation of somatosensory regions alters pyramidal cell spike timing and rates of sound stimuli. Moreover, in conditions of tinnitus, bimodal integration in DCN is enhanced, producing greater spontaneous and sound-driven neural activity, which are neural correlates of tinnitus. In primary auditory cortex (A1), a similar auditory-somatosensory integration has been described in the normal system (Lakatos et al., 2007), where sub-threshold multisensory modulation may be a direct reflection of subcortical multisensory responses (Tyll et al., 2011). The present work utilized simultaneous recordings from both DCN and A1 to directly compare bimodal integration across these separate brain stations of the intact auditory pathway. Four-shank, 32-channel electrodes were placed in DCN and A1 to simultaneously record tone-evoked unit activity in the presence and absence of spinal trigeminal nucleus (Sp5) electrical activation. Bimodal stimulation led to long-lasting facilitation or suppression of single and multi-unit responses to subsequent sound in both DCN and A1. Immediate (bimodal response) and long-lasting (bimodal plasticity) effects of Sp5-tone stimulation were facilitation or suppression of tone-evoked firing rates in DCN and A1 at all Sp5-tone pairing intervals (10, 20, and 40 ms), and greater suppression at 20 ms pairing-intervals for single unit responses. Understanding the complex relationships between DCN and A1 bimodal processing in the normal animal provides the basis for studying its disruption in hearing loss and tinnitus models. This article is part of a Special Issue entitled: Tinnitus Neuroscience.

  12. Decentralized Multisensory Information Integration in Neural Systems

    PubMed Central

    Zhang, Wen-hao; Chen, Aihua

    2016-01-01

    How multiple sensory cues are integrated in neural circuitry remains a challenge. The common hypothesis is that information integration might be accomplished in a dedicated multisensory integration area receiving feedforward inputs from the modalities. However, recent experimental evidence suggests that it is not a single multisensory brain area, but rather many multisensory brain areas that are simultaneously involved in the integration of information. Why many mutually connected areas should be needed for information integration is puzzling. Here, we investigated theoretically how information integration could be achieved in a distributed fashion within a network of interconnected multisensory areas. Using biologically realistic neural network models, we developed a decentralized information integration system that comprises multiple interconnected integration areas. Studying an example of combining visual and vestibular cues to infer heading direction, we show that such a decentralized system is in good agreement with anatomical evidence and experimental observations. In particular, we show that this decentralized system can integrate information optimally. The decentralized system predicts that optimally integrated information should emerge locally from the dynamics of the communication between brain areas and sheds new light on the interpretation of the connectivity between multisensory brain areas. SIGNIFICANCE STATEMENT To extract information reliably from ambiguous environments, the brain integrates multiple sensory cues, which provide different aspects of information about the same entity of interest. Here, we propose a decentralized architecture for multisensory integration. In such a system, no processor is in the center of the network topology and information integration is achieved in a distributed manner through reciprocally connected local processors. Through studying the inference of heading direction with visual and vestibular cues, we show that

  13. Computing Multisensory Target Probabilities on a Neural Map

    DTIC Science & Technology

    2007-11-02

    integrates multisensory input and participates in the generation of orienting movements directed toward the source of sensory stimulation (target). The deep...Computing Multisensory Target Probabilities on a Neural Map T. J. Anastasio1,2, P. E. Patton2 1,2Department of Molecular and Integrative Physiology...SC neurons exhibit multisensory enhancement, in which the response to input of one modality is augmented by input of another modality. Multisensory

  14. A multisensory perspective on object memory.

    PubMed

    Matusz, Pawel J; Wallace, Mark T; Murray, Micah M

    2017-04-08

    Traditional studies of memory and object recognition involved objects presented within a single sensory modality (i.e., purely visual or purely auditory objects). However, in naturalistic settings, objects are often evaluated and processed in a multisensory manner. This begets the question of how object representations that combine information from the different senses are created and utilised by memory functions. Here we review research that has demonstrated that a single multisensory exposure can influence memory for both visual and auditory objects. In an old/new object discrimination task, objects that were presented initially with a task-irrelevant stimulus in another sense were better remembered compared to stimuli presented alone, most notably when the two stimuli were semantically congruent. The brain discriminates between these two types of object representations within the first 100ms post-stimulus onset, indicating early "tagging" of objects/events by the brain based on the nature of their initial presentation context. Interestingly, the specific brain networks supporting the improved object recognition vary based on a variety of factors, including the effectiveness of the initial multisensory presentation and the sense that is task-relevant. We specify the requisite conditions for multisensory contexts to improve object discrimination following single exposures, and the individual differences that exist with respect to these improvements. Our results shed light onto how memory operates on the multisensory nature of object representations as well as how the brain stores and retrieves memories of objects.

  15. Multisensory body representation in autoimmune diseases.

    PubMed

    Finotti, Gianluca; Costantini, Marcello

    2016-02-12

    Body representation has been linked to the processing and integration of multisensory signals. An outstanding example of the pivotal role played by multisensory mechanisms in body representation is the Rubber Hand Illusion (RHI). In this paradigm, multisensory stimulation induces a sense of ownership over a fake limb. Previous work has shown high interindividual differences in the susceptibility to the RHI. The origin of this variability remains largely unknown. Given the tight and bidirectional communication between the brain and the immune system, we predicted that the origin of this variability could be traced, in part, to the immune system's functioning, which is altered by several clinical conditions, including Coeliac Disease (CD). Consistent with this prediction, we found that the Rubber Hand Illusion is stronger in CD patients as compared to healthy controls. We propose a biochemical mechanism accounting for the dependency of multisensory body representation upon the Immune system. Our finding has direct implications for a range of neurological, psychiatric and immunological conditions where alterations of multisensory integration, body representation and dysfunction of the immune system co-exist.

  16. Multisensory body representation in autoimmune diseases

    PubMed Central

    Finotti, Gianluca; Costantini, Marcello

    2016-01-01

    Body representation has been linked to the processing and integration of multisensory signals. An outstanding example of the pivotal role played by multisensory mechanisms in body representation is the Rubber Hand Illusion (RHI). In this paradigm, multisensory stimulation induces a sense of ownership over a fake limb. Previous work has shown high interindividual differences in the susceptibility to the RHI. The origin of this variability remains largely unknown. Given the tight and bidirectional communication between the brain and the immune system, we predicted that the origin of this variability could be traced, in part, to the immune system’s functioning, which is altered by several clinical conditions, including Coeliac Disease (CD). Consistent with this prediction, we found that the Rubber Hand Illusion is stronger in CD patients as compared to healthy controls. We propose a biochemical mechanism accounting for the dependency of multisensory body representation upon the Immune system. Our finding has direct implications for a range of neurological, psychiatric and immunological conditions where alterations of multisensory integration, body representation and dysfunction of the immune system co-exist. PMID:26867786

  17. Causal Inference in Multisensory Heading Estimation

    PubMed Central

    Katliar, Mikhail; Bülthoff, Heinrich H.

    2017-01-01

    A large body of research shows that the Central Nervous System (CNS) integrates multisensory information. However, this strategy should only apply to multisensory signals that have a common cause; independent signals should be segregated. Causal Inference (CI) models account for this notion. Surprisingly, previous findings suggested that visual and inertial cues on heading of self-motion are integrated regardless of discrepancy. We hypothesized that CI does occur, but that characteristics of the motion profiles affect multisensory processing. Participants estimated heading of visual-inertial motion stimuli with several different motion profiles and a range of intersensory discrepancies. The results support the hypothesis that judgments of signal causality are included in the heading estimation process. Moreover, the data suggest a decreasing tolerance for discrepancies and an increasing reliance on visual cues for longer duration motions. PMID:28060957

  18. Functional Analytic Multisensory Environmental Therapy for People with Dementia

    PubMed Central

    Staal, Jason A.

    2012-01-01

    This paper introduces Functional Analytic Multisensory Environmental Therapy (FAMSET) for use with elders with dementia while using a multisensory environment/snoezelen room. The model introduces behavioral theory and practice to the multisensory environment treatment, addressing assessment, and, within session techniques, integrating behavioral interventions with emotion-oriented care. A modular approach is emphasized to delineate different treatment phases for multisensory environment therapy. The aim of the treatment is to provide a safe and effective framework for reducing the behavioral disturbance of the disease process, increasing elder well-being, and to promote transfer of positive effects to other environments outside of the multisensory treatment room. PMID:22347667

  19. The Complex Interplay Between Multisensory Integration and Perceptual Awareness.

    PubMed

    Deroy, O; Faivre, N; Lunghi, C; Spence, C; Aller, M; Noppeney, U

    2016-01-01

    The integration of information has been considered a hallmark of human consciousness, as it requires information being globally available via widespread neural interactions. Yet the complex interdependencies between multisensory integration and perceptual awareness, or consciousness, remain to be defined. While perceptual awareness has traditionally been studied in a single sense, in recent years we have witnessed a surge of interest in the role of multisensory integration in perceptual awareness. Based on a recent IMRF symposium on multisensory awareness, this review discusses three key questions from conceptual, methodological and experimental perspectives: (1) What do we study when we study multisensory awareness? (2) What is the relationship between multisensory integration and perceptual awareness? (3) Which experimental approaches are most promising to characterize multisensory awareness? We hope that this review paper will provoke lively discussions, novel experiments, and conceptual considerations to advance our understanding of the multifaceted interplay between multisensory integration and consciousness.

  20. The Complex Interplay Between Multisensory Integration and Perceptual Awareness

    PubMed Central

    Aller, M.; Noppeney, U.

    2016-01-01

    The integration of information has been considered a hallmark of human consciousness, as it requires information being globally available via widespread neural interactions. Yet the complex interdependencies between multisensory integration and perceptual awareness, or consciousness, remain to be defined. While perceptual awareness has traditionally been studied in a single sense, in recent years we have witnessed a surge of interest in the role of multisensory integration in perceptual awareness. Based on a recent IMRF symposium on multisensory awareness, this review discusses three key questions from conceptual, methodological and experimental perspectives: (1) What do we study when we study multisensory awareness? (2) What is the relationship between multisensory integration and perceptual awareness? (3) Which experimental approaches are most promising to characterize multisensory awareness? We hope that this review paper will provoke lively discussions, novel experiments, and conceptual considerations to advance our understanding of the multifaceted interplay between multisensory integration and consciousness. PMID:27795942

  1. Multisensory integration, sensory substitution and visual rehabilitation.

    PubMed

    Proulx, Michael J; Ptito, Maurice; Amedi, Amir

    2014-04-01

    Sensory substitution has advanced remarkably over the past 35 years since first introduced to the scientific literature by Paul Bach-y-Rita. In this issue dedicated to his memory, we describe a collection of reviews that assess the current state of neuroscience research on sensory substitution, visual rehabilitation, and multisensory processes.

  2. Multisensory Instruction in Foreign Language Education.

    ERIC Educational Resources Information Center

    Robles, Teresita del Rosario Caballero; Uglem, Craig Thomas Chase

    This paper reviews some theories that through history have explained the process of learning. It also taps some new findings on how the brain learns. Multisensory instruction is a pedagogic strategy that covers the greatest number of individual preferences in the classroom, language laboratories, and multimedia rooms for a constant and diverse…

  3. Improving Vocabulary Acquisition with Multisensory Instruction

    ERIC Educational Resources Information Center

    D'Alesio, Rosemary; Scalia, Maureen T.; Zabel, Renee M.

    2007-01-01

    The purpose of this action research project was to improve student vocabulary acquisition through a multisensory, direct instructional approach. The study involved three teachers and a target population of 73 students in second and seventh grade classrooms. The intervention was implemented from September through December of 2006 and analyzed in…

  4. Laminar and Connectional Organization of a Multisensory Cortex

    PubMed Central

    Foxworthy, W. Alex; Clemo, H. Ruth; Meredith, M. Alex

    2012-01-01

    The transformation of sensory signals as they pass through cortical circuits has been revealed almost exclusively through studies of the primary sensory cortices, where principles of laminar organization, local connectivity and parallel processing have been elucidated. In contrast, almost nothing is known about the circuitry or laminar features of multisensory processing in higher-order, multisensory cortex. Therefore, using the ferret higher-order multisensory rostral posterior parietal (PPr) cortex, the present investigation employed a combination of multichannel recording and neuroanatomical techniques to elucidate the laminar basis of multisensory cortical processing. The proportion of multisensory neurons, the share of neurons showing multisensory integration, and the magnitude of multisensory integration were all found to differ by layer in a way that matched the functional or connectional characteristics of the PPr. Specifically, the supragranular layers (L2–3) demonstrated among the highest proportions of multisensory neurons and the highest incidence of multisensory response enhancement, while also receiving the highest levels of extrinsic inputs, exhibiting the highest dendritic spine densities, and providing a major source of local connectivity. In contrast, layer 6 showed the highest proportion of unisensory neurons while receiving the fewest external and local projections and exhibiting the lowest dendritic spine densities. Coupled with a lack of input from principal thalamic nuclei and a minimal layer 4, these observations indicate that this higher-level multisensory cortex shows unique functional and organizational modifications from the well-known patterns identified for primary sensory cortical regions. PMID:23172137

  5. The interactions of multisensory integration with endogenous and exogenous attention.

    PubMed

    Tang, Xiaoyu; Wu, Jinglong; Shen, Yong

    2016-02-01

    Stimuli from multiple sensory organs can be integrated into a coherent representation through multiple phases of multisensory processing; this phenomenon is called multisensory integration. Multisensory integration can interact with attention. Here, we propose a framework in which attention modulates multisensory processing in both endogenous (goal-driven) and exogenous (stimulus-driven) ways. Moreover, multisensory integration exerts not only bottom-up but also top-down control over attention. Specifically, we propose the following: (1) endogenous attentional selectivity acts on multiple levels of multisensory processing to determine the extent to which simultaneous stimuli from different modalities can be integrated; (2) integrated multisensory events exert top-down control on attentional capture via multisensory search templates that are stored in the brain; (3) integrated multisensory events can capture attention efficiently, even in quite complex circumstances, due to their increased salience compared to unimodal events and can thus improve search accuracy; and (4) within a multisensory object, endogenous attention can spread from one modality to another in an exogenous manner.

  6. Laminar and connectional organization of a multisensory cortex.

    PubMed

    Foxworthy, W Alex; Clemo, H Ruth; Meredith, M Alex

    2013-06-01

    The transformation of sensory signals as they pass through cortical circuits has been revealed almost exclusively through studies of the primary sensory cortices, for which principles of laminar organization, local connectivity, and parallel processing have been elucidated. In contrast, almost nothing is known about the circuitry or laminar features of multisensory processing in higher order, multisensory cortex. Therefore, using the ferret higher order multisensory rostral posterior parietal (PPr) cortex, the present investigation employed a combination of multichannel recording and neuroanatomical techniques to elucidate the laminar basis of multisensory cortical processing. The proportion of multisensory neurons, the share of neurons showing multisensory integration, and the magnitude of multisensory integration were all found to differ by layer in a way that matched the functional or connectional characteristics of the PPr. Specifically, the supragranular layers (L2/3) demonstrated among the highest proportions of multisensory neurons and the highest incidence of multisensory response enhancement, while also receiving the highest levels of extrinsic inputs, exhibiting the highest dendritic spine densities, and providing a major source of local connectivity. In contrast, layer 6 showed the highest proportion of unisensory neurons while receiving the fewest external and local projections and exhibiting the lowest dendritic spine densities. Coupled with a lack of input from principal thalamic nuclei and a minimal layer 4, these observations indicate that this higher level multisensory cortex shows functional and organizational modifications from the well-known patterns identified for primary sensory cortical regions.

  7. The interactions of multisensory integration with endogenous and exogenous attention

    PubMed Central

    Tang, Xiaoyu; Wu, Jinglong; Shen, Yong

    2016-01-01

    Stimuli from multiple sensory organs can be integrated into a coherent representation through multiple phases of multisensory processing; this phenomenon is called multisensory integration. Multisensory integration can interact with attention. Here, we propose a framework in which attention modulates multisensory processing in both endogenous (goal-driven) and exogenous (stimulus-driven) ways. Moreover, multisensory integration exerts not only bottom-up but also top-down control over attention. Specifically, we propose the following: (1) endogenous attentional selectivity acts on multiple levels of multisensory processing to determine the extent to which simultaneous stimuli from different modalities can be integrated; (2) integrated multisensory events exert top-down control on attentional capture via multisensory search templates that are stored in the brain; (3) integrated multisensory events can capture attention efficiently, even in quite complex circumstances, due to their increased salience compared to unimodal events and can thus improve search accuracy; and (4) within a multisensory object, endogenous attention can spread from one modality to another in an exogenous manner. PMID:26546734

  8. Where are multisensory signals combined for perceptual decision-making?

    PubMed

    Bizley, Jennifer K; Jones, Gareth P; Town, Stephen M

    2016-10-01

    Multisensory integration is observed in many subcortical and cortical locations including primary and non-primary sensory cortex, and higher cortical areas including frontal and parietal cortex. During unisensory perceptual tasks many of these same brain areas show neural signatures associated with decision-making. It is unclear whether multisensory representations in sensory cortex directly inform decision-making in a multisensory task, or if cross-modal signals are only combined after the accumulation of unisensory evidence at a final decision-making stage in higher cortical areas. Manipulations of neuronal activity are required to establish causal roles for given brain regions in multisensory perceptual decision-making, and so far indicate that distributed networks underlie multisensory decision-making. Understanding multisensory integration requires synthesis of small-scale pathway specific and large-scale network level manipulations.

  9. Multisensory Mechanisms of Gaze Stabilization and Flight Control

    DTIC Science & Technology

    2008-12-17

    Multisensory mechanisms of gaze stabilization and flight control 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 5d. TASK NUMBER 6. AUTHOR(S...email: h.g.krapp@imperial.ac.uk Imperial College South Kensington Campus London SW7 2AZ “ Multisensory Mechanisms of Gaze... Multisensory Integration, and Efference Copies in Behaving Animals 2.5 State-dependent Processing in LPTCs 2.6 Characterization of Head Movements in the

  10. Multisensory integration and attention in developmental dyslexia.

    PubMed

    Harrar, Vanessa; Tammam, Jonathan; Pérez-Bellido, Alexis; Pitt, Anna; Stein, John; Spence, Charles

    2014-03-03

    Developmental dyslexia affects 5%-10% of the population, resulting in poor spelling and reading skills. While there are well-documented differences in the way dyslexics process low-level visual and auditory stimuli, it is mostly unknown whether there are similar differences in audiovisual multisensory processes. Here, we investigated audiovisual integration using the redundant target effect (RTE) paradigm. Some conditions demonstrating audiovisual integration appear to depend upon magnocellular pathways, and dyslexia has been associated with deficits in this pathway; so, we postulated that developmental dyslexics ("dyslexics" hereafter) would show differences in audiovisual integration compared with controls. Reaction times (RTs) to multisensory stimuli were compared with predictions from Miller's race model. Dyslexics showed difficulty shifting their attention between modalities; but such "sluggish attention shifting" (SAS) appeared only when dyslexics shifted their attention from the visual to the auditory modality. These results suggest that dyslexics distribute their crossmodal attention resources differently from controls, causing different patterns in multisensory responses compared to controls. From this, we propose that dyslexia training programs should take into account the asymmetric shifts of crossmodal attention.

  11. Behavioural benefits of multisensory processing in ferrets.

    PubMed

    Hammond-Kenny, Amy; Bajo, Victoria M; King, Andrew J; Nodal, Fernando R

    2017-01-01

    Enhanced detection and discrimination, along with faster reaction times, are the most typical behavioural manifestations of the brain's capacity to integrate multisensory signals arising from the same object. In this study, we examined whether multisensory behavioural gains are observable across different components of the localization response that are potentially under the command of distinct brain regions. We measured the ability of ferrets to localize unisensory (auditory or visual) and spatiotemporally coincident auditory-visual stimuli of different durations that were presented from one of seven locations spanning the frontal hemifield. During the localization task, we recorded the head movements made following stimulus presentation, as a metric for assessing the initial orienting response of the ferrets, as well as the subsequent choice of which target location to approach to receive a reward. Head-orienting responses to auditory-visual stimuli were more accurate and faster than those made to visual but not auditory targets, suggesting that these movements were guided principally by sound alone. In contrast, approach-to-target localization responses were more accurate and faster to spatially congruent auditory-visual stimuli throughout the frontal hemifield than to either visual or auditory stimuli alone. Race model inequality analysis of head-orienting reaction times and approach-to-target response times indicates that different processes, probability summation and neural integration, respectively, are likely to be responsible for the effects of multisensory stimulation on these two measures of localization behaviour.

  12. The Relationship between Multisensory Integration and IQ in Children

    ERIC Educational Resources Information Center

    Barutchu, Ayla; Crewther, Sheila G.; Fifer, Joanne; Shivdasani, Mohit N.; Innes-Brown, Hamish; Toohey, Sarah; Danaher, Jaclyn; Paolini, Antonio G.

    2011-01-01

    It is well accepted that multisensory integration has a facilitative effect on perceptual and motor processes, evolutionarily enhancing the chance of survival of many species, including humans. Yet, there is limited understanding of the relationship between multisensory processes, environmental noise, and children's cognitive abilities. Thus, this…

  13. Anthro-Centric Multisensory Interface for Vision Augmentation/Substitution

    DTIC Science & Technology

    2011-02-01

    Anthro-Centric Multisensory Interface for Vision Augmentation/Substitution) PRINCIPAL INVESTIGATOR: Anil Raj, MD...TYPE Annual 3. DATES COVERED (From - To) 15 Jan 2011 – 31 JAN 2011 4. TITLE AND SUBTITLE Anthro-Centric Multisensory Interface for Vision ...Interface Vision Augmentation/Substitution (ACMI-VAS) project, the research team developed an integrated system that can substitute tactile stimulation

  14. Using Multisensory Phonics to Foster Reading Skills of Adolescent Delinquents

    ERIC Educational Resources Information Center

    Warnick, Kristan; Caldarella, Paul

    2016-01-01

    This study examined the effectiveness of a multisensory phonics-based reading remediation program for adolescent delinquents classified as poor readers living at a residential treatment center. We used a pretest--posttest control group design with random assignment. The treatment group participated in a 30-hr multisensory phonics reading…

  15. Uncovering Multisensory Processing through Non-Invasive Brain Stimulation.

    PubMed

    Bolognini, Nadia; Maravita, Angelo

    2011-01-01

    Most of current knowledge about the mechanisms of multisensory integration of environmental stimuli by the human brain derives from neuroimaging experiments. However, neuroimaging studies do not always provide conclusive evidence about the causal role of a given area for multisensory interactions, since these techniques can mainly derive correlations between brain activations and behavior. Conversely, techniques of non-invasive brain stimulation (NIBS) represent a unique and powerful approach to inform models of causal relations between specific brain regions and individual cognitive and perceptual functions. Although NIBS has been widely used in cognitive neuroscience, its use in the study of multisensory processing in the human brain appears a quite novel field of research. In this paper, we review and discuss recent studies that have used two techniques of NIBS, namely transcranial magnetic stimulation and transcranial direct current stimulation, for investigating the causal involvement of unisensory and heteromodal cortical areas in multisensory processing, the effects of multisensory cues on cortical excitability in unisensory areas, and the putative functional connections among different cortical areas subserving multisensory interactions. The emerging view is that NIBS is an essential tool available to neuroscientists seeking for causal relationships between a given area or network and multisensory processes. With its already large and fast increasing usage, future work using NIBS in isolation, as well as in conjunction with different neuroimaging techniques, could substantially improve our understanding of multisensory processing in the human brain.

  16. The COGs (context, object, and goals) in multisensory processing.

    PubMed

    ten Oever, Sanne; Romei, Vincenzo; van Atteveldt, Nienke; Soto-Faraco, Salvador; Murray, Micah M; Matusz, Pawel J

    2016-05-01

    Our understanding of how perception operates in real-world environments has been substantially advanced by studying both multisensory processes and "top-down" control processes influencing sensory processing via activity from higher-order brain areas, such as attention, memory, and expectations. As the two topics have been traditionally studied separately, the mechanisms orchestrating real-world multisensory processing remain unclear. Past work has revealed that the observer's goals gate the influence of many multisensory processes on brain and behavioural responses, whereas some other multisensory processes might occur independently of these goals. Consequently, other forms of top-down control beyond goal dependence are necessary to explain the full range of multisensory effects currently reported at the brain and the cognitive level. These forms of control include sensitivity to stimulus context as well as the detection of matches (or lack thereof) between a multisensory stimulus and categorical attributes of naturalistic objects (e.g. tools, animals). In this review we discuss and integrate the existing findings that demonstrate the importance of such goal-, object- and context-based top-down control over multisensory processing. We then put forward a few principles emerging from this literature review with respect to the mechanisms underlying multisensory processing and discuss their possible broader implications.

  17. TMS of posterior parietal cortex disrupts visual tactile multisensory integration.

    PubMed

    Pasalar, Siavash; Ro, Tony; Beauchamp, Michael S

    2010-05-01

    Functional neuroimaging studies have implicated a number of brain regions, especially the posterior parietal cortex (PPC), as being potentially important for visual-tactile multisensory integration. However, neuroimaging studies are correlational and do not prove the necessity of a region for the behavioral improvements that are the hallmark of multisensory integration. To remedy this knowledge gap, we interrupted activity in the PPC, near the junction of the anterior intraparietal sulcus and the postcentral sulcus, using MRI-guided transcranial magnetic stimulation (TMS) while subjects localized touches delivered to different fingers. As the touches were delivered, subjects viewed a congruent touch video, an incongruent touch video, or no video. Without TMS, a strong effect of multisensory integration was observed, with significantly better behavioral performance for discrimination of congruent multisensory touch than for unisensory touch alone. Incongruent multisensory touch produced a smaller improvement in behavioral performance. TMS of the PPC eliminated the behavioral advantage of both congruent and incongruent multisensory stimuli, reducing performance to unisensory levels. These results demonstrate a causal role for the PPC in visual-tactile multisensory integration. Taken together with converging evidence from other studies, these results support a model in which the PPC contains a map of space around the hand that receives input from both the visual and somatosensory modalities. Activity in this map is likely to be the neural substrate for visual-tactile multisensory integration.

  18. Multisensory Modalities for Blending and Segmenting among Early Readers

    ERIC Educational Resources Information Center

    Lee, Lay Wah

    2016-01-01

    With the advent of touch-screen interfaces on the tablet computer, multisensory elements in reading instruction have taken on a new dimension. This computer assisted language learning research aimed to determine whether specific technology features of a tablet computer can add to the functionality of multisensory instruction in early reading…

  19. Multisensory Teaching of Basic Language Skills Activity Book. Revised Edition

    ERIC Educational Resources Information Center

    Carreker, Suzanne; Birsh, Judith R.

    2011-01-01

    With the new edition of this activity book--the companion to Judith Birsh's bestselling text, "Multisensory Teaching of Basic Language Skills"--students and practitioners will get the practice they need to use multisensory teaching effectively with students who have dyslexia and other learning disabilities. Ideal for both pre-service teacher…

  20. Multisensory Processes: A Balancing Act across the Lifespan.

    PubMed

    Murray, Micah M; Lewkowicz, David J; Amedi, Amir; Wallace, Mark T

    2016-08-01

    Multisensory processes are fundamental in scaffolding perception, cognition, learning, and behavior. How and when stimuli from different sensory modalities are integrated rather than treated as separate entities is poorly understood. We review how the relative reliance on stimulus characteristics versus learned associations dynamically shapes multisensory processes. We illustrate the dynamism in multisensory function across two timescales: one long term that operates across the lifespan and one short term that operates during the learning of new multisensory relations. In addition, we highlight the importance of task contingencies. We conclude that these highly dynamic multisensory processes, based on the relative weighting of stimulus characteristics and learned associations, provide both stability and flexibility to brain functions over a wide range of temporal scales.

  1. A model of the temporal dynamics of multisensory enhancement

    PubMed Central

    Rowland, Benjamin A.; Stein, Barry E.

    2014-01-01

    The senses transduce different forms of environmental energy, and the brain synthesizes information across them to enhance responses to salient biological events. We hypothesize that the potency of multisensory integration is attributable to the convergence of independent and temporally aligned signals derived from cross-modal stimulus configurations onto multisensory neurons. The temporal profile of multisensory integration in neurons of the deep superior colliculus (SC) is consistent with this hypothesis. The responses of these neurons to visual, auditory, and combinations of visual–auditory stimuli reveal that multisensory integration takes place in real-time; that is, the input signals are integrated as soon as they arrive at the target neuron. Interactions between cross-modal signals may appear to reflect linear or nonlinear computations on a moment-by-moment basis, the aggregate of which determines the net product of multisensory integration. Modeling observations presented here suggest that the early nonlinear components of the temporal profile of multisensory integration can be explained with a simple spiking neuron model, and do not require more sophisticated assumptions about the underlying biology. A transition from nonlinear “super-additive” computation to linear, additive computation can be accomplished via scaled inhibition. The findings provide a set of design constraints for artificial implementations seeking to exploit the basic principles and potency of biological multisensory integration in contexts of sensory substitution or augmentation. PMID:24374382

  2. The effects of visual training on multisensory temporal processing

    PubMed Central

    Stevenson, Ryan A.; Wilson, Magdalena M.; Powers, Albert R.; Wallace, Mark T.

    2013-01-01

    The importance of multisensory integration for human behavior and perception is well documented, as is the impact that temporal synchrony has on driving such integration. Thus, the more temporally coincident two sensory inputs from different modalities are, the more likely they will be perceptually bound. This temporal integration process is captured by the construct of the temporal binding window - the range of temporal offsets within which an individual is able to perceptually bind inputs across sensory modalities. Recent work has shown that this window is malleable, and can be narrowed via a multisensory perceptual feedback training process. In the current study, we seek to extend this by examining the malleability of the multisensory temporal binding window through changes in unisensory experience. Specifically, we measured the ability of visual perceptual feedback training to induce changes in the multisensory temporal binding window. Visual perceptual training with feedback successfully improved temporal visual processing and more importantly, this visual training increased the temporal precision across modalities, which manifested as a narrowing of the multisensory temporal binding window. These results are the first to establish the ability of unisensory temporal training to modulate multisensory temporal processes, findings that can provide mechanistic insights into multisensory integration and which may have a host of practical applications. PMID:23307155

  3. The multisensory function of the human primary visual cortex.

    PubMed

    Murray, Micah M; Thelen, Antonia; Thut, Gregor; Romei, Vincenzo; Martuzzi, Roberto; Matusz, Pawel J

    2016-03-01

    It has been nearly 10 years since Ghazanfar and Schroeder (2006) proposed that the neocortex is essentially multisensory in nature. However, it is only recently that sufficient and hard evidence that supports this proposal has accrued. We review evidence that activity within the human primary visual cortex plays an active role in multisensory processes and directly impacts behavioural outcome. This evidence emerges from a full pallet of human brain imaging and brain mapping methods with which multisensory processes are quantitatively assessed by taking advantage of particular strengths of each technique as well as advances in signal analyses. Several general conclusions about multisensory processes in primary visual cortex of humans are supported relatively solidly. First, haemodynamic methods (fMRI/PET) show that there is both convergence and integration occurring within primary visual cortex. Second, primary visual cortex is involved in multisensory processes during early post-stimulus stages (as revealed by EEG/ERP/ERFs as well as TMS). Third, multisensory effects in primary visual cortex directly impact behaviour and perception, as revealed by correlational (EEG/ERPs/ERFs) as well as more causal measures (TMS/tACS). While the provocative claim of Ghazanfar and Schroeder (2006) that the whole of neocortex is multisensory in function has yet to be demonstrated, this can now be considered established in the case of the human primary visual cortex.

  4. Bayesian-based integration of multisensory naturalistic perithreshold stimuli.

    PubMed

    Regenbogen, Christina; Johansson, Emilia; Andersson, Patrik; Olsson, Mats J; Lundström, Johan N

    2016-07-29

    Most studies exploring multisensory integration have used clearly perceivable stimuli. According to the principle of inverse effectiveness, the added neural and behavioral benefit of integrating clear stimuli is reduced in comparison to stimuli with degraded and less salient unisensory information. Traditionally, speed and accuracy measures have been analyzed separately with few studies merging these to gain an understanding of speed-accuracy trade-offs in multisensory integration. In two separate experiments, we assessed multisensory integration of naturalistic audio-visual objects consisting of individually-tailored perithreshold dynamic visual and auditory stimuli, presented within a multiple-choice task, using a Bayesian Hierarchical Drift Diffusion Model that combines response time and accuracy. For both experiments, unisensory stimuli were degraded to reach a 75% identification accuracy level for all individuals and stimuli to promote multisensory binding. In Experiment 1, we subsequently presented uni- and their respective bimodal stimuli followed by a 5-alternative-forced-choice task. In Experiment 2, we controlled for low-level integration and attentional differences. Both experiments demonstrated significant superadditive multisensory integration of bimodal perithreshold dynamic information. We present evidence that the use of degraded sensory stimuli may provide a link between previous findings of inverse effectiveness on a single neuron level and overt behavior. We further suggest that a combined measure of accuracy and reaction time may be a more valid and holistic approach of studying multisensory integration and propose the application of drift diffusion models for studying behavioral correlates as well as brain-behavior relationships of multisensory integration.

  5. Neonatal cortical ablation disrupts multisensory development in superior colliculus

    PubMed Central

    Jiang, Wan; Jiang, Huai; Stein, Barry E.

    2006-01-01

    The ability of cat superior colliculus (SC) neurons to synthesize information from different senses depends on influences from two areas of the cortex: the anterior ectosylvian sulcus (AES) and the rostral lateral suprasylvian sulcus (rLS). Reversibly deactivating the inputs to the SC from either of these areas in normal adults severely compromises this ability and the SC-mediated behaviors that depend on it. In the present study we found that removal of these areas in neonatal animals precluded the normal development of multisensory SC processes. At maturity there was a substantial decrease in the incidence of multisensory neurons, and those multisensory neurons that did develop were highly abnormal. Their cross-modal receptive field register was severely compromised, as was their ability to integrate cross-modal stimuli. Apparently, despite the impressive plasticity of the neonatal brain, it cannot compensate for the early loss of these cortices. Surprisingly, however, neonatal removal of either AES or rLS had comparatively minor consequences on these properties. At maturity multisensory SC neurons were quite common: they developed the characteristic spatial register among their unisensory receptive fields and exhibited normal adult-like multisensory integration. These observations suggest that during early ontogeny, when the multisensory properties of SC neurons are being crafted, AES and rLS may have the ability to compensate for the loss of one another’s cortico-collicular influences so that normal multisensory processes can develop in the SC. PMID:16267111

  6. A rational analysis of the acquisition of multisensory representations.

    PubMed

    Yildirim, Ilker; Jacobs, Robert A

    2012-03-01

    How do people learn multisensory, or amodal, representations, and what consequences do these representations have for perceptual performance? We address this question by performing a rational analysis of the problem of learning multisensory representations. This analysis makes use of a Bayesian nonparametric model that acquires latent multisensory features that optimally explain the unisensory features arising in individual sensory modalities. The model qualitatively accounts for several important aspects of multisensory perception: (a) it integrates information from multiple sensory sources in such a way that it leads to superior performances in, for example, categorization tasks; (b) its performances suggest that multisensory training leads to better learning than unisensory training, even when testing is conducted in unisensory conditions; (c) its multisensory representations are modality invariant; and (d) it predicts ''missing" sensory representations in modalities when the input to those modalities is absent. Our rational analysis indicates that all of these aspects emerge as part of the optimal solution to the problem of learning to represent complex multisensory environments.

  7. The effects of visual training on multisensory temporal processing.

    PubMed

    Stevenson, Ryan A; Wilson, Magdalena M; Powers, Albert R; Wallace, Mark T

    2013-04-01

    The importance of multisensory integration for human behavior and perception is well documented, as is the impact that temporal synchrony has on driving such integration. Thus, the more temporally coincident two sensory inputs from different modalities are, the more likely they will be perceptually bound. This temporal integration process is captured by the construct of the temporal binding window-the range of temporal offsets within which an individual is able to perceptually bind inputs across sensory modalities. Recent work has shown that this window is malleable and can be narrowed via a multisensory perceptual feedback training process. In the current study, we seek to extend this by examining the malleability of the multisensory temporal binding window through changes in unisensory experience. Specifically, we measured the ability of visual perceptual feedback training to induce changes in the multisensory temporal binding window. Visual perceptual training with feedback successfully improved temporal visual processing, and more importantly, this visual training increased the temporal precision across modalities, which manifested as a narrowing of the multisensory temporal binding window. These results are the first to establish the ability of unisensory temporal training to modulate multisensory temporal processes, findings that can provide mechanistic insights into multisensory integration and which may have a host of practical applications.

  8. Multisensory temporal integration: Task and stimulus dependencies

    PubMed Central

    Stevenson, Ryan A.; Wallace, Mark T.

    2013-01-01

    The ability of human sensory systems to integrate information across the different modalities provides a wide range of behavioral and perceptual benefits. This integration process is dependent upon the temporal relationship of the different sensory signals, with stimuli occurring close together in time typically resulting in the largest behavior changes. The range of temporal intervals over which such benefits are seen is typically referred to as the temporal binding window (TBW). Given the importance of temporal factors in multisensory integration under both normal and atypical circumstances such as autism and dyslexia, the TBW has been measured with a variety of experimental protocols that differ according to criterion, task, and stimulus type, making comparisons across experiments difficult. In the current study we attempt to elucidate the role that these various factors play in the measurement of this important construct. The results show a strong effect of stimulus type, with the TBW assessed with speech stimuli being both larger and more symmetrical than that seen using simple and complex non-speech stimuli. These effects are robust across task and statistical criteria, and are highly consistent within individuals, suggesting substantial overlap in the neural and cognitive operations that govern multisensory temporal processes. PMID:23604624

  9. Multisensory perceptual learning and sensory substitution.

    PubMed

    Proulx, Michael J; Brown, David J; Pasqualotto, Achille; Meijer, Peter

    2014-04-01

    One of the most exciting recent findings in neuroscience has been the capacity for neural plasticity in adult humans and animals. Studies of perceptual learning have provided key insights into the mechanisms of neural plasticity and the changes in functional neuroanatomy that it affords. Key questions in this field of research concern how practice of a task leads to specific or general improvement. Although much of this work has been carried out with a focus on a single sensory modality, primarily visual, there is increasing interest in multisensory perceptual learning. Here we will examine how advances in perceptual learning research both inform and can be informed by the development and advancement of sensory substitution devices for blind persons. To allow 'sight' to occur in the absence of visual input through the eyes, visual information can be transformed by a sensory substitution device into a representation that can be processed as sound or touch, and thus give one the potential to 'see' through the ears or tongue. Investigations of auditory, visual and multisensory perceptual learning can have key benefits for the advancement of sensory substitution, and the study of sensory deprivation and sensory substitution likewise will further the understanding of perceptual learning in general and the reverse hierarchy theory in particular. It also has significant importance for the developing understanding of the brain in metamodal terms, where functional brain areas might be best defined by the computations they carry out rather than by their sensory-specific processing role.

  10. The question of simultaneity in multisensory integration

    NASA Astrophysics Data System (ADS)

    Leone, Lynnette; McCourt, Mark E.

    2012-03-01

    Early reports of audiovisual (AV) multisensory integration (MI) indicated that unisensory stimuli must evoke simultaneous physiological responses to produce decreases in reaction time (RT) such that for unisensory stimuli with unequal RTs the stimulus eliciting the faster RT had to be delayed relative to the stimulus eliciting the slower RT. The "temporal rule" states that MI depends on the temporal proximity of unisensory stimuli, the neural responses to which must fall within a window of integration. Ecological validity demands that MI should occur only for simultaneous events (which may give rise to non-simultaneous neural activations). However, spurious neural response simultaneities which are unrelated to singular environmental multisensory occurrences must somehow be rejected. Using an RT/race model paradigm we measured AV MI as a function of stimulus onset asynchrony (SOA: +/-200 ms, 50 ms intervals) under fully dark adapted conditions for visual (V) stimuli that were either weak (scotopic 525 nm flashes; 511 ms mean RT) or strong (photopic 630 nm flashes; 356 ms mean RT). Auditory (A) stimulus (1000 Hz pure tone) intensity was constant. Despite the 155 ms slower mean RT to the scotopic versus photopic stimulus, facilitative AV MI in both conditions nevertheless occurred exclusively at an SOA of 0 ms. Thus, facilitative MI demands both physical and physiological simultaneity. We consider the mechanisms by which the nervous system may take account of variations in response latency arising from changes in stimulus intensity in order to selectively integrate only those physiological simultaneities that arise from physical simultaneities.

  11. Multisensory architectures for action-oriented perception

    NASA Astrophysics Data System (ADS)

    Alba, L.; Arena, P.; De Fiore, S.; Listán, J.; Patané, L.; Salem, A.; Scordino, G.; Webb, B.

    2007-05-01

    In order to solve the navigation problem of a mobile robot in an unstructured environment a versatile sensory system and efficient locomotion control algorithms are necessary. In this paper an innovative sensory system for action-oriented perception applied to a legged robot is presented. An important problem we address is how to utilize a large variety and number of sensors, while having systems that can operate in real time. Our solution is to use sensory systems that incorporate analog and parallel processing, inspired by biological systems, to reduce the required data exchange with the motor control layer. In particular, as concerns the visual system, we use the Eye-RIS v1.1 board made by Anafocus, which is based on a fully parallel mixed-signal array sensor-processor chip. The hearing sensor is inspired by the cricket hearing system and allows efficient localization of a specific sound source with a very simple analog circuit. Our robot utilizes additional sensors for touch, posture, load, distance, and heading, and thus requires customized and parallel processing for concurrent acquisition. Therefore a Field Programmable Gate Array (FPGA) based hardware was used to manage the multi-sensory acquisition and processing. This choice was made because FPGAs permit the implementation of customized digital logic blocks that can operate in parallel allowing the sensors to be driven simultaneously. With this approach the multi-sensory architecture proposed can achieve real time capabilities.

  12. The multisensory brain and its ability to learn music.

    PubMed

    Zimmerman, Emily; Lahav, Amir

    2012-04-01

    Playing a musical instrument requires a complex skill set that depends on the brain's ability to quickly integrate information from multiple senses. It has been well documented that intensive musical training alters brain structure and function within and across multisensory brain regions, supporting the experience-dependent plasticity model. Here, we argue that this experience-dependent plasticity occurs because of the multisensory nature of the brain and may be an important contributing factor to musical learning. This review highlights key multisensory regions within the brain and discusses their role in the context of music learning and rehabilitation.

  13. On the relative contributions of multisensory integration and crossmodal exogenous spatial attention to multisensory response enhancement.

    PubMed

    Van der Stoep, N; Spence, C; Nijboer, T C W; Van der Stigchel, S

    2015-11-01

    Two processes that can give rise to multisensory response enhancement (MRE) are multisensory integration (MSI) and crossmodal exogenous spatial attention. It is, however, currently unclear what the relative contribution of each of these is to MRE. We investigated this issue using two tasks that are generally assumed to measure MSI (a redundant target effect task) and crossmodal exogenous spatial attention (a spatial cueing task). One block of trials consisted of unimodal auditory and visual targets designed to provide a unimodal baseline. In two other blocks of trials, the participants were presented with spatially and temporally aligned and misaligned audiovisual (AV) targets (0, 50, 100, and 200ms SOA). In the integration block, the participants were instructed to respond to the onset of the first target stimulus that they detected (A or V). The instruction for the cueing block was to respond only to the onset of the visual targets. The targets could appear at one of three locations: left, center, and right. The participants were instructed to respond only to lateral targets. The results indicated that MRE was caused by MSI at 0ms SOA. At 50ms SOA, both crossmodal exogenous spatial attention and MSI contributed to the observed MRE, whereas the MRE observed at the 100 and 200ms SOAs was attributable to crossmodal exogenous spatial attention, alerting, and temporal preparation. These results therefore suggest that there may be a temporal window in which both MSI and exogenous crossmodal spatial attention can contribute to multisensory response enhancement.

  14. Multisensory enhancement of electromotor responses to a single moving object.

    PubMed

    Pluta, Scott R; Kawasaki, Masashi

    2008-09-01

    Weakly electric fish possess three cutaneous sensory organs structured in arrays with overlapping receptive fields. Theoretically, these tuberous electrosensory, ampullary electrosensory and mechanosensory lateral line receptors receive spatiotemporally congruent stimulation in the presence of a moving object. The current study is the first to quantify the magnitude of multisensory enhancement across these mechanosensory and electrosensory systems during moving-object recognition. We used the novelty response of a pulse-type weakly electric fish to quantitatively compare multisensory responses to their component unisensory responses. Principally, we discovered that multisensory novelty responses are significantly larger than their arithmetically summed component unisensory responses. Additionally, multimodal stimulation yielded a significant increase in novelty response amplitude, probability and the rate of a high-frequency burst, known as a ;scallop'. Supralinear multisensory enhancement of the novelty response may signify an augmentation of perception driven by the ecological significance of multimodal stimuli. Scalloping may function as a sensory scan aimed at rapidly facilitating the electrolocation of novel stimuli.

  15. Initiating the development of multisensory integration by manipulating sensory experience

    PubMed Central

    Yu, Liping; Rowland, Benjamin A.; Stein, Barry E.

    2010-01-01

    The multisensory integration capabilities of superior colliculus (SC) neurons emerge gradually during early postnatal life as a consequence of experience with cross-modal stimuli. Without such experience neurons become responsive to multiple sensory modalities but are unable to integrate their inputs. The present study demonstrates that neurons retain sensitivity to cross-modal experience well past the normal developmental period for acquiring multisensory integration capabilities. Experience surprisingly late in life was found to rapidly initiate the development of multisensory integration, even more rapidly than expected based on its normal developmental time course. Furthermore, the requisite experience was acquired by the anesthetized brain and in the absence of any of the stimulus-response contingencies generally associated with learning. The key experiential factor was repeated exposure to the relevant stimuli, and this required that the multiple receptive fields of a multisensory neuron encompassed the cross-modal exposure site. Simple exposure to the individual components of a cross-modal stimulus was ineffective in this regard. Furthermore, once a neuron acquired multisensory integration capabilities at the exposure site, it generalized this experience to other locations, albeit with lowered effectiveness. These observations suggest that the prolonged period during which multisensory integration normally appears is due to developmental factors in neural circuitry in addition to those required for incorporating the statistics of cross-modal events; that neurons learn a multisensory principle based on the specifics of experience and can then apply it to other stimulus conditions; and that the incorporation of this multisensory information does not depend on an alert brain. PMID:20371810

  16. Looming signals reveal synergistic principles of multisensory integration.

    PubMed

    Cappe, Céline; Thelen, Antonia; Romei, Vincenzo; Thut, Gregor; Murray, Micah M

    2012-01-25

    Multisensory interactions are a fundamental feature of brain organization. Principles governing multisensory processing have been established by varying stimulus location, timing and efficacy independently. Determining whether and how such principles operate when stimuli vary dynamically in their perceived distance (as when looming/receding) provides an assay for synergy among the above principles and also means for linking multisensory interactions between rudimentary stimuli with higher-order signals used for communication and motor planning. Human participants indicated movement of looming or receding versus static stimuli that were visual, auditory, or multisensory combinations while 160-channel EEG was recorded. Multivariate EEG analyses and distributed source estimations were performed. Nonlinear interactions between looming signals were observed at early poststimulus latencies (∼75 ms) in analyses of voltage waveforms, global field power, and source estimations. These looming-specific interactions positively correlated with reaction time facilitation, providing direct links between neural and performance metrics of multisensory integration. Statistical analyses of source estimations identified looming-specific interactions within the right claustrum/insula extending inferiorly into the amygdala and also within the bilateral cuneus extending into the inferior and lateral occipital cortices. Multisensory effects common to all conditions, regardless of perceived distance and congruity, followed (∼115 ms) and manifested as faster transition between temporally stable brain networks (vs summed responses to unisensory conditions). We demonstrate the early-latency, synergistic interplay between existing principles of multisensory interactions. Such findings change the manner in which to model multisensory interactions at neural and behavioral/perceptual levels. We also provide neurophysiologic backing for the notion that looming signals receive preferential

  17. The efficacy of single-trial multisensory memories.

    PubMed

    Thelen, Antonia; Murray, Micah M

    2013-01-01

    This review article summarizes evidence that multisensory experiences at one point in time have long-lasting effects on subsequent unisensory visual and auditory object recognition. The efficacy of single-trial exposure to task-irrelevant multisensory events is its ability to modulate memory performance and brain activity to unisensory components of these events presented later in time. Object recognition (either visual or auditory) is enhanced if the initial multisensory experience had been semantically congruent and can be impaired if this multisensory pairing was either semantically incongruent or entailed meaningless information in the task-irrelevant modality, when compared to objects encountered exclusively in a unisensory context. Processes active during encoding cannot straightforwardly explain these effects; performance on all initial presentations was indistinguishable despite leading to opposing effects with stimulus repetitions. Brain responses to unisensory stimulus repetitions differ during early processing stages (-100 ms post-stimulus onset) according to whether or not they had been initially paired in a multisensory context. Plus, the network exhibiting differential responses varies according to whether or not memory performance is enhanced or impaired. The collective findings we review indicate that multisensory associations formed via single-trial learning exert influences on later unisensory processing to promote distinct object representations that manifest as differentiable brain networks whose activity is correlated with memory performance. These influences occur incidentally, despite many intervening stimuli, and are distinguishable from the encoding/learning processes during the formation of the multisensory associations. The consequences of multisensory interactions that persist over time to impact memory retrieval and object discrimination.

  18. Initiating the development of multisensory integration by manipulating sensory experience.

    PubMed

    Yu, Liping; Rowland, Benjamin A; Stein, Barry E

    2010-04-07

    The multisensory integration capabilities of superior colliculus neurons emerge gradually during early postnatal life as a consequence of experience with cross-modal stimuli. Without such experience neurons become responsive to multiple sensory modalities but are unable to integrate their inputs. The present study demonstrates that neurons retain sensitivity to cross-modal experience well past the normal developmental period for acquiring multisensory integration capabilities. Experience surprisingly late in life was found to rapidly initiate the development of multisensory integration, even more rapidly than expected based on its normal developmental time course. Furthermore, the requisite experience was acquired by the anesthetized brain and in the absence of any of the stimulus-response contingencies generally associated with learning. The key experiential factor was repeated exposure to the relevant stimuli, and this required that the multiple receptive fields of a multisensory neuron encompassed the cross-modal exposure site. Simple exposure to the individual components of a cross-modal stimulus was ineffective in this regard. Furthermore, once a neuron acquired multisensory integration capabilities at the exposure site, it generalized this experience to other locations, albeit with lowered effectiveness. These observations suggest that the prolonged period during which multisensory integration normally appears is due to developmental factors in neural circuitry in addition to those required for incorporating the statistics of cross-modal events; that neurons learn a multisensory principle based on the specifics of experience and can then apply it to other stimulus conditions; and that the incorporation of this multisensory information does not depend on an alert brain.

  19. Multisensory dysfunction accompanies crossmodal plasticity following adult hearing impairment.

    PubMed

    Meredith, M A; Keniston, L P; Allman, B L

    2012-07-12

    Until now, cortical crossmodal plasticity has largely been regarded as the effect of early and complete sensory loss. Recently, massive crossmodal cortical reorganization was demonstrated to result from profound hearing loss in adult ferrets (Allman et al., 2009a). Moderate adult hearing loss, on the other hand, induced not just crossmodal reorganization, but also merged new crossmodal inputs with residual auditory function to generate multisensory neurons. Because multisensory convergence can lead to dramatic levels of response integration when stimuli from more than one modality are present (and thereby potentially interfere with residual auditory processing), the present investigation sought to evaluate the multisensory properties of auditory cortical neurons in partially deafened adult ferrets. When compared with hearing controls, partially-deaf animals revealed elevated spontaneous levels and a dramatic increase (∼2 times) in the proportion of multisensory cortical neurons, but few of which showed multisensory integration. Moreover, a large proportion (68%) of neurons with somatosensory and/or visual inputs was vigorously active in core auditory cortex in the absence of auditory stimulation. Collectively, these results not only demonstrate multisensory dysfunction in core auditory cortical neurons from hearing impaired adults but also reveal a potential cortical substrate for maladaptive perceptual effects such as tinnitus.

  20. Modeling of multisensory convergence with a network of spiking neurons: a reverse engineering approach.

    PubMed

    Lim, Hun Ki; Keniston, Leslie P; Cios, Krzysztof J

    2011-07-01

    Multisensory processing in the brain underlies a wide variety of perceptual phenomena, but little is known about the underlying mechanisms of how multisensory neurons are formed. This lack of knowledge is due to the difficulty for biological experiments to manipulate and test the parameters of multisensory convergence, the first and definitive step in the multisensory process. Therefore, by using a computational model of multisensory convergence, this study seeks to provide insight into the mechanisms of multisensory convergence. To reverse-engineer multisensory convergence, we used a biologically realistic neuron model and a biology-inspired plasticity rule, but did not make any a priori assumptions about multisensory properties of neurons in the network. The network consisted of two separate projection areas that converged upon neurons in a third area, and stimulation involved activation of one of the projection areas (or the other) or their combination. Experiments consisted of two parts: network training and multisensory simulation. Analyses were performed, first, to find multisensory properties in the simulated networks; second, to reveal properties of the network using graph theoretical approach; and third, to generate hypothesis related to the multisensory convergence. The results showed that the generation of multisensory neurons related to the topological properties of the network, in particular, the strengths of connections after training, was found to play an important role in forming and thus distinguishing multisensory neuron types.

  1. Voluntary initiation of movement: multifunctional integration of subjective agency.

    PubMed

    Grüneberg, Patrick; Kadone, Hideki; Suzuki, Kenji

    2015-01-01

    This paper investigates subjective agency (SA) as a special type of efficacious action consciousness. Our central claims are, firstly, that SA is a conscious act of voluntarily initiating bodily motion. Secondly, we argue that SA is a case of multifunctional integration of behavioral functions being analogous to multisensory integration of sensory modalities. This is based on new perspectives on the initiation of action opened up by recent advancements in robot assisted neuro-rehabilitation which depends on the active participation of the patient and yields experimental evidence that there is SA in terms of a conscious act of voluntarily initiating bodily motion (phenomenal performance). Conventionally, action consciousness has been considered as a sense of agency (SoA). According to this view, the conscious subject merely echoes motor performance and does not cause bodily motion. Depending on sensory input, SoA is implemented by means of unifunctional integration (binding) and inevitably results in non-efficacious action consciousness. In contrast, SA comes as a phenomenal performance which causes motion and builds on multifunctional integration. Therefore, the common conception of the brain should be shifted toward multifunctional integration in order to allow for efficacious action consciousness. For this purpose, we suggest the heterarchic principle of asymmetric reciprocity and neural operators underlying SA. The general idea is that multifunctional integration allows conscious acts to be simultaneously implemented with motor behavior so that the resulting behavior (SA) comes as efficacious action consciousness. Regarding the neural implementation, multifunctional integration rather relies on operators than on modular functions. A robotic case study and possible experimental setups with testable hypotheses building on SA are presented.

  2. Voluntary initiation of movement: multifunctional integration of subjective agency

    PubMed Central

    Grüneberg, Patrick; Kadone, Hideki; Suzuki, Kenji

    2015-01-01

    This paper investigates subjective agency (SA) as a special type of efficacious action consciousness. Our central claims are, firstly, that SA is a conscious act of voluntarily initiating bodily motion. Secondly, we argue that SA is a case of multifunctional integration of behavioral functions being analogous to multisensory integration of sensory modalities. This is based on new perspectives on the initiation of action opened up by recent advancements in robot assisted neuro-rehabilitation which depends on the active participation of the patient and yields experimental evidence that there is SA in terms of a conscious act of voluntarily initiating bodily motion (phenomenal performance). Conventionally, action consciousness has been considered as a sense of agency (SoA). According to this view, the conscious subject merely echoes motor performance and does not cause bodily motion. Depending on sensory input, SoA is implemented by means of unifunctional integration (binding) and inevitably results in non-efficacious action consciousness. In contrast, SA comes as a phenomenal performance which causes motion and builds on multifunctional integration. Therefore, the common conception of the brain should be shifted toward multifunctional integration in order to allow for efficacious action consciousness. For this purpose, we suggest the heterarchic principle of asymmetric reciprocity and neural operators underlying SA. The general idea is that multifunctional integration allows conscious acts to be simultaneously implemented with motor behavior so that the resulting behavior (SA) comes as efficacious action consciousness. Regarding the neural implementation, multifunctional integration rather relies on operators than on modular functions. A robotic case study and possible experimental setups with testable hypotheses building on SA are presented. PMID:26052308

  3. Multisensory integration during short-term music reading training enhances both uni- and multisensory cortical processing.

    PubMed

    Paraskevopoulos, Evangelos; Kuchenbuch, Anja; Herholz, Sibylle C; Pantev, Christo

    2014-10-01

    The human ability to integrate the input of several sensory systems is essential for building a meaningful interpretation out of the complexity of the environment. Training studies have shown that the involvement of multiple senses during training enhances neuroplasticity, but it is not clear to what extent integration of the senses during training is required for the observed effects. This study intended to elucidate the differential contributions of uni- and multisensory elements of music reading training in the resulting plasticity of abstract audiovisual incongruency identification. We used magnetoencephalography to measure the pre- and posttraining cortical responses of two randomly assigned groups of participants that followed either an audiovisual music reading training that required multisensory integration (AV-Int group) or a unisensory training that had separate auditory and visual elements (AV-Sep group). Results revealed a network of frontal generators for the abstract audiovisual incongruency response, confirming previous findings, and indicated the central role of anterior prefrontal cortex in this process. Differential neuroplastic effects of the two types of training in frontal and temporal regions point to the crucial role of multisensory integration occurring during training. Moreover, a comparison of the posttraining cortical responses of both groups to a group of musicians that were tested using the same paradigm revealed that long-term music training leads to significantly greater responses than the short-term training of the AV-Int group in anterior prefrontal regions as well as to significantly greater responses than both short-term training protocols in the left superior temporal gyrus (STG).

  4. The effect of multisensory cues on attention in aging.

    PubMed

    Mahoney, Jeannette R; Verghese, Joe; Dumas, Kristina; Wang, Cuiling; Holtzer, Roee

    2012-09-07

    The attention network test (ANT) assesses the effect of alerting and orienting cues on a visual flanker task measuring executive attention. Previous findings revealed that older adults demonstrate greater reaction times (RT) benefits when provided with visual orienting cues that offer both spatial and temporal information of an ensuing target. Given the overlap of neural substrates and networks involved in multisensory processing and cueing (i.e., alerting and orienting), an investigation of multisensory cueing effects on RT was warranted. The current study was designed to determine whether participants, both old and young, benefited from receiving multisensory alerting and orienting cues. Eighteen young (M=19.17 years; 45% female) and eighteen old (M=76.44 years; 61% female) individuals that were determined to be non-demented and without any medical or psychiatric conditions that would affect their performance were included. Results revealed main effects for the executive attention and orienting networks, but not for the alerting network. In terms of orienting, both old and young adults demonstrated significant orienting effects for auditory-somatosensory (AS), auditory-visual (AV), and visual-somatosensory (VS) cues. RT benefits of multisensory compared to unisensory orienting effects differed by cue type and age group; younger adults demonstrated greater RT benefits for AS orienting cues whereas older adults demonstrated greater RT benefits for AV orienting cues. Both groups, however, demonstrated significant RT benefits for multisensory VS orienting cues. These findings provide evidence for the facilitative effect of multisensory orienting cues, and not multisensory alerting cues, in old and young adults.

  5. Multisensory integration, aging, and the sound-induced flash illusion.

    PubMed

    DeLoss, Denton J; Pierce, Russell S; Andersen, George J

    2013-09-01

    The present study examined age-related differences in multisensory integration and the role of attention in age-related differences in multisensory integration. The sound-induced flash illusion--the misperception of the number of visual flashes due to the simultaneous presentation of a different number of auditory beeps--was used to examine the strength of multisensory integration in older and younger observers. The effects of integration were examined when discriminating 1-3 flashes, 1-3 beeps, or 1-3 flashes presented with 1-3 beeps. Stimulus conditions were blocked according to these conditions with baseline (unisensory) performance assessed during the multisensory block. Older participants demonstrated greater multisensory integration--a greater influence of the beeps when judging the number of visual flashes--than younger observers. In a second experiment, the role of attention was assessed using a go/no-go paradigm. The results of Experiment 2 replicated those of Experiment 1. In addition, the strength of the illusion was modulated by the sensory domain of the go/no-go task, though this did not differ by age group. In the visual go/no-go task we found a decrease in the illusion, yet in the auditory go/no-go task we found an increase in the illusion. These results demonstrate that older individuals exhibit increased multisensory integration compared with younger individuals. Attention was also found to modulate the strength of the sound-induced flash illusion. However, the results also suggest that attention was not likely to be a factor in the age-related differences in multisensory integration.

  6. Development of multisensory reweighting for posture control in children.

    PubMed

    Bair, Woei-Nan; Kiemel, Tim; Jeka, John J; Clark, Jane E

    2007-12-01

    Reweighting to multisensory inputs adaptively contributes to stable and flexible upright stance control. However, few studies have examined how early a child develops multisensory reweighting ability, or how this ability develops through childhood. The purpose of the study was to characterize a developmental landscape of multisensory reweighting for upright postural control in children 4-10 years of age. Children were presented with simultaneous small-amplitude somatosensory and visual environmental movement at 0.28 and 0.2 Hz, respectively, within five conditions that independently varied the amplitude of the stimuli. The primary measure was body sway amplitude relative to each stimulus: touch gain and vision gain. We found that children can reweight to multisensory inputs from 4 years on. Specifically, intra-modal reweighting was exhibited by children as young as 4 years of age; however, inter-modal reweighting was only observed in the older children. The amount of reweighting increased with age indicating development of a better adaptive ability. Our results rigorously demonstrate the development of simultaneous reweighting to two sensory inputs for postural control in children. The present results provide further evidence that the development of multisensory reweighting contributes to more stable and flexible control of upright stance, which ultimately serves as the foundation for functional behaviors such as locomotion and reaching.

  7. Multisensory simultaneity judgment and proximity to the body

    PubMed Central

    Noel, Jean-Paul; Łukowska, Marta; Wallace, Mark; Serino, Andrea

    2016-01-01

    The integration of information across different sensory modalities is known to be dependent upon the statistical characteristics of the stimuli to be combined. For example, the spatial and temporal proximity of stimuli are important determinants with stimuli that are close in space and time being more likely to be bound. These multisensory interactions occur not only for singular points in space/time, but over “windows” of space and time that likely relate to the ecological statistics of real-world stimuli. Relatedly, human psychophysical work has demonstrated that individuals are highly prone to judge multisensory stimuli as co-occurring over a wide range of time—a so-called simultaneity window (SW). Similarly, there exists a spatial representation of peripersonal space (PPS) surrounding the body in which stimuli related to the body and to external events occurring near the body are highly likely to be jointly processed. In the current study, we sought to examine the interaction between these temporal and spatial dimensions of multisensory representation by measuring the SW for audiovisual stimuli through proximal–distal space (i.e., PPS and extrapersonal space). Results demonstrate that the audiovisual SWs within PPS are larger than outside PPS. In addition, we suggest that this effect is likely due to an automatic and additional computation of these multisensory events in a body-centered reference frame. We discuss the current findings in terms of the spatiotemporal constraints of multisensory interactions and the implication of distinct reference frames on this process. PMID:26891828

  8. Neuromodulation of early multisensory interactions in the visual cortex.

    PubMed

    Convento, Silvia; Vallar, Giuseppe; Galantini, Chiara; Bolognini, Nadia

    2013-05-01

    Merging information derived from different sensory channels allows the brain to amplify minimal signals to reduce their ambiguity, thereby improving the ability of orienting to, detecting, and identifying environmental events. Although multisensory interactions have been mostly ascribed to the activity of higher-order heteromodal areas, multisensory convergence may arise even in primary sensory-specific areas located very early along the cortical processing stream. In three experiments, we investigated early multisensory interactions in lower-level visual areas, by using a novel approach, based on the coupling of behavioral stimulation with two noninvasive brain stimulation techniques, namely, TMS and transcranial direct current stimulation (tDCS). First, we showed that redundant multisensory stimuli can increase visual cortical excitability, as measured by means of phosphene induction by occipital TMS; such physiological enhancement is followed by a behavioral facilitation through the amplification of signal intensity in sensory-specific visual areas. The more sensory inputs are combined (i.e., trimodal vs. bimodal stimuli), the greater are the benefits on phosphene perception. Second, neuroelectrical activity changes induced by tDCS in the temporal and in the parietal cortices, but not in the occipital cortex, can further boost the multisensory enhancement of visual cortical excitability, by increasing the auditory and tactile inputs from temporal and parietal regions, respectively, to lower-level visual areas.

  9. Greater benefits of multisensory integration during complex sensorimotor transformations.

    PubMed

    Buchholz, Verena N; Goonetilleke, Samanthi C; Medendorp, W Pieter; Corneil, Brian D

    2012-06-01

    Multisensory integration enables rapid and accurate behavior. To orient in space, sensory information registered initially in different reference frames has to be integrated with the current postural information to produce an appropriate motor response. In some postures, multisensory integration requires convergence of sensory evidence across hemispheres, which would presumably lessen or hinder integration. Here, we examined orienting gaze shifts in humans to visual, tactile, or visuotactile stimuli when the hands were either in a default uncrossed posture or a crossed posture requiring convergence across hemispheres. Surprisingly, we observed the greatest benefits of multisensory integration in the crossed posture, as indexed by reaction time (RT) decreases. Moreover, such shortening of RTs to multisensory stimuli did not come at the cost of increased error propensity. To explain these results, we propose that two accepted principles of multisensory integration, the spatial principle and inverse effectiveness, dynamically interact to aid the rapid and accurate resolution of complex sensorimotor transformations. First, early mutual inhibition of initial visual and tactile responses registered in different hemispheres reduces error propensity. Second, inverse effectiveness in the integration of the weakened visual response with the remapped tactile representation expedites the generation of the correct motor response. Our results imply that the concept of inverse effectiveness, which is usually associated with external stimulus properties, might extend to internal spatial representations that are more complex given certain body postures.

  10. Multifunctionality in molecular magnetism.

    PubMed

    Pinkowicz, Dawid; Czarnecki, Bernard; Reczyński, Mateusz; Arczyński, Mirosław

    2015-01-01

    Molecular magnetism draws from the fundamental ideas of structural chemistry and combines them with experimental physics resulting in one of the highest profile current topics, namely molecular materials that exhibit multifunctionality. Recent advances in the design of new generations of multifunctional molecular magnets that retain the functions of the building blocks and exhibit non-trivial magnetic properties at higher temperatures provide promising evidence that they may be useful for the future construction of nanoscale devices. This article is not a complete review but is rather an introduction into thefascinating world of multifunctional solids with magnetism as the leitmotif. We provide a subjective selection and discussion of the most inspiring examples of multifunctional molecular magnets: magnetic sponges, guest-responsive magnets, molecular magnets with ionic conductivity, photomagnets and non-centrosymmetric and chiral magnets.

  11. Multifunctional cellulase and hemicellulase

    SciTech Connect

    Fox, Brian G.; Takasuka, Taichi; Bianchetti, Christopher M.

    2015-09-29

    A multifunctional polypeptide capable of hydrolyzing cellulosic materials, xylan, and mannan is disclosed. The polypeptide includes the catalytic core (cc) of Clostridium thermocellum Cthe_0797 (CelE), the cellulose-specific carbohydrate-binding module CBM3 of the cellulosome anchoring protein cohesion region (CipA) of Clostridium thermocellum (CBM3a), and a linker region interposed between the catalytic core and the cellulose-specific carbohydrate binding module. Methods of using the multifunctional polypeptide are also disclosed.

  12. Multifunctional thin film surface

    DOEpatents

    Brozik, Susan M.; Harper, Jason C.; Polsky, Ronen; Wheeler, David R.; Arango, Dulce C.; Dirk, Shawn M.

    2015-10-13

    A thin film with multiple binding functionality can be prepared on an electrode surface via consecutive electroreduction of two or more aryl-onium salts with different functional groups. This versatile and simple method for forming multifunctional surfaces provides an effective means for immobilization of diverse molecules at close proximities. The multifunctional thin film has applications in bioelectronics, molecular electronics, clinical diagnostics, and chemical and biological sensing.

  13. The function of consciousness in multisensory integration.

    PubMed

    Palmer, Terry D; Ramsey, Ashley K

    2012-12-01

    The function of consciousness was explored in two contexts of audio-visual speech, cross-modal visual attention guidance and McGurk cross-modal integration. Experiments 1, 2, and 3 utilized a novel cueing paradigm in which two different flash suppressed lip-streams cooccured with speech sounds matching one of these streams. A visual target was then presented at either the audio-visually congruent or incongruent location. Target recognition differed for the congruent versus incongruent trials, and the nature of this difference depended on the probabilities of a target appearing at these respective locations. Thus, even though the lip-streams were never consciously perceived, they were nevertheless meaningfully integrated with the consciously perceived sounds, and participants learned to guide their attention according to statistical regularities between targets and these unconsciously perceived cross-modal cues. In Experiment 4, McGurk stimuli were presented in which the lip-streams were either flash suppressed (4a) or unsuppressed (4b), and the McGurk effect was found to vanish under conditions of flash suppression. Overall, these results suggest a simple yet fundamental principle regarding the function of consciousness in multisensory integration - cross-modal effects can occur in the absence of consciousness, but the influencing modality must be consciously perceived for its information to cross modalities.

  14. Capturing spatial attention with multisensory cues.

    PubMed

    Santangelo, Valerio; Ho, Cristy; Spence, Charles

    2008-04-01

    We assessed the influence ofmultisensory interactions on the exogenous orienting of spatial attention by comparing the ability of auditory, tactile, and audiotactile exogenous cues to capture visuospatial attention under conditions of no perceptual load versus high perceptual load. In Experiment 1, participants discriminated the elevation of visual targets preceded by either unimodal or bimodal cues under conditions of either a high perceptual load (involving the monitoring of a rapidly presented central stream of visual letters for occasionally presented target digits) or no perceptual load (when the central stream was replaced by a fixation point). All of the cues captured spatial attention in the no-load condition, whereas only the bimodal cues captured visuospatial attention in the high-load condition. In Experiment 2, we ruled out the possibility that the presentation of any changing stimulus at fixation (i.e., a passively monitored stream of letters) would eliminate exogenous orienting, which instead appears to be a consequence of high perceptual load conditions (Experiment 1). These results demonstrate that multisensory cues capture spatial attention more effectively than unimodal cues under conditions of concurrent perceptual load.

  15. A multisensory algorithm of satellite radiothermovision

    NASA Astrophysics Data System (ADS)

    Ermakov, D. M.; Sharkov, E. A.; Chernushich, A. P.

    2016-12-01

    A multisensory algorithm of satellite radiothermovision has been proposed that makes it possible to combine the data of satellite radiothermal monitoring of the Earth from different sources within a single method of spatiotemporal interpolation taking into account the differences in time of measurements and in the spatial resolution of different instruments. The new algorithm was tested in a series of measurements with SSMIS instruments onboard F16, F17 satellites of DMSP and AMSR-2 instruments onboard the GCOMW1 satellite in November 2013, as well as a series of measurements with the same instruments in August 2012 supplemented with data from WindSat. The parameters of the spatiotemporal interpolation of total precipitable water fields are improved nearly twofold (with a time step of 1.5 h on a regular grid with 0.125° sampling) compared with the method that previously used only SSM/I data. The achieved spatial sampling exceeds known world analogues while maintaining a high accuracy of interpolation. In addition, the problem of the transition from the fields at a fixed local time to the fields at a fixed universal time is briefly considered. It has been shown that this transition is mainly relevant in the study of the fast atmospheric processes on a global scale with high temporal resolution.

  16. Multisensory Integration in the Virtual Hand Illusion with Active Movement

    PubMed Central

    Satoh, Satoru; Hachimura, Kozaburo

    2016-01-01

    Improving the sense of immersion is one of the core issues in virtual reality. Perceptual illusions of ownership can be perceived over a virtual body in a multisensory virtual reality environment. Rubber Hand and Virtual Hand Illusions showed that body ownership can be manipulated by applying suitable visual and tactile stimulation. In this study, we investigate the effects of multisensory integration in the Virtual Hand Illusion with active movement. A virtual xylophone playing system which can interactively provide synchronous visual, tactile, and auditory stimulation was constructed. We conducted two experiments regarding different movement conditions and different sensory stimulations. Our results demonstrate that multisensory integration with free active movement can improve the sense of immersion in virtual reality. PMID:27847822

  17. Synchronous multisensory stimulation blurs self-other boundaries.

    PubMed

    Paladino, Maria-Paola; Mazzurega, Mara; Pavani, Francesco; Schubert, Thomas W

    2010-09-01

    In a study that builds on recent cognitive neuroscience research on body perception and social psychology research on social relations, we tested the hypothesis that synchronous multisensory stimulation leads to self-other merging. We brushed the cheek of each study participant as he or she watched a stranger's cheek being brushed in the same way, either in synchrony or in asynchrony. We found that this multisensory procedure had an effect on participants' body perception as well as social perception. Study participants exposed to synchronous stimulation showed more merging of self and the other than participants exposed to asynchronous stimulation. The degree of self-other merging was determined by measuring participants' body sensations and their perception of face resemblance, as well as participants' judgment of the inner state of the other, closeness felt toward the other, and conformity behavior. The results of this study show how multisensory integration can affect social perception and create a sense of self-other similarity.

  18. Senses make sense: An individualized multisensory stimulation for dementia.

    PubMed

    Cui, Yuanwu; Shen, Minxue; Ma, Yan; Wen, Shi Wu

    2017-01-01

    Nonpharmacologic interventions have been recommended as first-line treatments for dementia, and multisensory stimulation environment has been used as a non-pharmacological treatment to dementia patients in the last decade. However, the clinical effect of multisensory stimulation environment remains temporary and uncertain. Individualized medicine has been suggested to hold great promise in medicine, and it should be equally important for dementia. Reminiscence integrating individual experiences into therapeutic schemes has shown potential in the field of improving cognitive functions and depressive symptoms for dementia patients, and interactive music also demonstrated a positive outcome by using individualized music for the hearing aspect. We therefore hypothesize that an individualized multisensory stimulation in a natural and realistic environment integrating personal experience may be an effective intervention for patients suffering from dementia.

  19. Multisensory integration in complete unawareness: evidence from audiovisual congruency priming.

    PubMed

    Faivre, Nathan; Mudrik, Liad; Schwartz, Naama; Koch, Christof

    2014-11-01

    Multisensory integration is thought to require conscious perception. Although previous studies have shown that an invisible stimulus could be integrated with an audible one, none have demonstrated integration of two subliminal stimuli of different modalities. Here, pairs of identical or different audiovisual target letters (the sound /b/ with the written letter "b" or "m," respectively) were preceded by pairs of masked identical or different audiovisual prime digits (the sound /6/ with the written digit "6" or "8," respectively). In three experiments, awareness of the audiovisual digit primes was manipulated, such that participants were either unaware of the visual digit, the auditory digit, or both. Priming of the semantic relations between the auditory and visual digits was found in all experiments. Moreover, a further experiment showed that unconscious multisensory integration was not obtained when participants did not undergo prior conscious training of the task. This suggests that following conscious learning, unconscious processing suffices for multisensory integration.

  20. Balanced crossmodal excitation and inhibition essential for maximizing multisensory gain.

    PubMed

    Hoshino, Osamu

    2014-07-01

    We examined whether and how the balancing of crossmodal excitation and inhibition affects intersensory facilitation. A neural network model, comprising lower-order unimodal networks (X, Y) and a higher-order multimodal network (M), was simulated. Crossmodal excitation was made by direct activation of principal cells of the X network by the Y network. Crossmodal inhibition was made in an indirect manner: the Y network activated glial cells of the X network. This let glial plasma membrane transporters export GABA molecules into the extracellular space and increased the level of ambient GABA. The ambient GABA molecules were accepted by extrasynaptic GABAa receptors and tonically inhibited principal cells of the X network. Namely, crossmodal inhibition was made through GABAergic gliotransmission. Intersensory facilitation was assessed in terms of multisensory gain: the difference between the numbers of spikes evoked by multisensory (XY) stimulation and unisensory (X-alone) stimulation. The maximal multisensory gain (XY-X) could be achieved at an intermediate noise level by balancing crossmodal excitation and inhibition. This result supports an experimentally derived conclusion: intersensory facilitation under noisy environmental conditions is not necessarily in accord with the principle of inverse effectiveness; rather, multisensory gain is maximal at intermediate signal-to-noise ratio (SNR) levels. The maximal multisensory gain was available at the weakest signal if noise was not present, indicating that the principle of inverse effectiveness is a special case of the intersensory facilitation model proposed here. We suggest that the balancing of crossmodal excitation and inhibition may be crucial for intersensory facilitation. The GABAergic glio-transmission-mediated crossmodal inhibitory mechanism effectively works for intersensory facilitation and on determining the maximal multisensory gain in the entire SNR range between the two extremes: low and high SNRs.

  1. A novel behavioral paradigm to assess multisensory processing in mice

    PubMed Central

    Siemann, Justin K.; Muller, Christopher L.; Bamberger, Gary; Allison, John D.; Veenstra-VanderWeele, Jeremy; Wallace, Mark T.

    2015-01-01

    Human psychophysical and animal behavioral studies have illustrated the benefits that can be conferred from having information available from multiple senses. Given the central role of multisensory integration for perceptual and cognitive function, it is important to design behavioral paradigms for animal models to provide mechanistic insights into the neural bases of these multisensory processes. Prior studies have focused on large mammals, yet the mouse offers a host of advantages, most importantly the wealth of available genetic manipulations relevant to human disease. To begin to employ this model species for multisensory research it is necessary to first establish and validate a robust behavioral assay for the mouse. Two common mouse strains (C57BL/6J and 129S6/SvEv) were first trained to respond to unisensory (visual and auditory) stimuli separately. Once trained, performance with paired audiovisual stimuli was then examined with a focus on response accuracy and behavioral gain. Stimulus durations varied from 50 ms to 1 s in order to modulate the effectiveness of the stimuli and to determine if the well-established “principle of inverse effectiveness” held in this model. Response accuracy in the multisensory condition was greater than for either unisensory condition for all stimulus durations, with significant gains observed at the 300 ms and 100 ms durations. Main effects of stimulus duration, stimulus modality and a significant interaction between these factors were observed. The greatest behavioral gain was seen for the 100 ms duration condition, with a trend observed that as the stimuli became less effective, larger behavioral gains were observed upon their pairing (i.e., inverse effectiveness). These results are the first to validate the mouse as a species that shows demonstrable behavioral facilitations under multisensory conditions and provides a platform for future mechanistically directed studies to examine the neural bases of multisensory

  2. Implicit multisensory associations influence voice recognition.

    PubMed

    von Kriegstein, Katharina; Giraud, Anne-Lise

    2006-10-01

    Natural objects provide partially redundant information to the brain through different sensory modalities. For example, voices and faces both give information about the speech content, age, and gender of a person. Thanks to this redundancy, multimodal recognition is fast, robust, and automatic. In unimodal perception, however, only part of the information about an object is available. Here, we addressed whether, even under conditions of unimodal sensory input, crossmodal neural circuits that have been shaped by previous associative learning become activated and underpin a performance benefit. We measured brain activity with functional magnetic resonance imaging before, while, and after participants learned to associate either sensory redundant stimuli, i.e. voices and faces, or arbitrary multimodal combinations, i.e. voices and written names, ring tones, and cell phones or brand names of these cell phones. After learning, participants were better at recognizing unimodal auditory voices that had been paired with faces than those paired with written names, and association of voices with faces resulted in an increased functional coupling between voice and face areas. No such effects were observed for ring tones that had been paired with cell phones or names. These findings demonstrate that brief exposure to ecologically valid and sensory redundant stimulus pairs, such as voices and faces, induces specific multisensory associations. Consistent with predictive coding theories, associative representations become thereafter available for unimodal perception and facilitate object recognition. These data suggest that for natural objects effective predictive signals can be generated across sensory systems and proceed by optimization of functional connectivity between specialized cortical sensory modules.

  3. Heterogeneity in the spatial receptive field architecture of multisensory neurons of the superior colliculus and its effects on multisensory integration.

    PubMed

    Ghose, D; Wallace, M T

    2014-01-03

    Multisensory integration has been widely studied in neurons of the mammalian superior colliculus (SC). This has led to the description of various determinants of multisensory integration, including those based on stimulus- and neuron-specific factors. The most widely characterized of these illustrate the importance of the spatial and temporal relationships of the paired stimuli as well as their relative effectiveness in eliciting a response in determining the final integrated output. Although these stimulus-specific factors have generally been considered in isolation (i.e., manipulating stimulus location while holding all other factors constant), they have an intrinsic interdependency that has yet to be fully elucidated. For example, changes in stimulus location will likely also impact both the temporal profile of response and the effectiveness of the stimulus. The importance of better describing this interdependency is further reinforced by the fact that SC neurons have large receptive fields, and that responses at different locations within these receptive fields are far from equivalent. To address these issues, the current study was designed to examine the interdependency between the stimulus factors of space and effectiveness in dictating the multisensory responses of SC neurons. The results show that neuronal responsiveness changes dramatically with changes in stimulus location - highlighting a marked heterogeneity in the spatial receptive fields of SC neurons. More importantly, this receptive field heterogeneity played a major role in the integrative product exhibited by stimulus pairings, such that pairings at weakly responsive locations of the receptive fields resulted in the largest multisensory interactions. Together these results provide greater insight into the interrelationship of the factors underlying multisensory integration in SC neurons, and may have important mechanistic implications for multisensory integration and the role it plays in shaping

  4. Multifunctional nanoparticles: analytical prospects.

    PubMed

    de Dios, Alejandro Simón; Díaz-García, Marta Elena

    2010-05-07

    Multifunctional nanoparticles are among the most exciting nanomaterials with promising applications in analytical chemistry. These applications include (bio)sensing, (bio)assays, catalysis and separations. Although most of these applications are based on the magnetic, optical and electrochemical properties of multifunctional nanoparticles, other aspects such as the synergistic effect of the functional groups and the amplification effect associated with the nanoscale dimension have also been observed. Considering not only the nature of the raw material but also the shape, there is a huge variety of nanoparticles. In this review only magnetic, quantum dots, gold nanoparticles, carbon and inorganic nanotubes as well as silica, titania and gadolinium oxide nanoparticles are addressed. This review presents a narrative summary on the use of multifunctional nanoparticles for analytical applications, along with a discussion on some critical challenges existing in the field and possible solutions that have been or are being developed to overcome these challenges.

  5. Mechanics of Multifunctional Materials & Microsystems

    DTIC Science & Technology

    2012-03-09

    Mechanics of Materials; Life Prediction (Materials & Micro-devices); Sensing, Precognition & Diagnosis; Multifunctional Design of Autonomic...Life Prediction (Materials & Micro-devices); Sensing, Precognition & Diagnosis; Multifunctional Design of Autonomic Systems; Multifunctional...release; distribution is unlimited. 7 VISION: EXPANDED • site specific • autonomic AUTONOMIC AEROSPACE STRUCTURES • Sensing & Precognition • Self

  6. Multisensory integration across the senses in young and old adults.

    PubMed

    Mahoney, Jeannette R; Li, Po Ching Clara; Oh-Park, Mooyeon; Verghese, Joe; Holtzer, Roee

    2011-12-02

    Stimuli are processed concurrently and across multiple sensory inputs. Here we directly compared the effect of multisensory integration (MSI) on reaction time across three paired sensory inputs in eighteen young (M=19.17 years) and eighteen old (M=76.44 years) individuals. Participants were determined to be non-demented and without any medical or psychiatric conditions that would affect their performance. Participants responded to randomly presented unisensory (auditory, visual, somatosensory) stimuli and three paired sensory inputs consisting of auditory-somatosensory (AS) auditory-visual (AV) and visual-somatosensory (VS) stimuli. Results revealed that reaction time (RT) to all multisensory pairings was significantly faster than those elicited to the constituent unisensory conditions across age groups; findings that could not be accounted for by simple probability summation. Both young and old participants responded the fastest to multisensory pairings containing somatosensory input. Compared to younger adults, older adults demonstrated a significantly greater RT benefit when processing concurrent VS information. In terms of co-activation, older adults demonstrated a significant increase in the magnitude of visual-somatosensory co-activation (i.e., multisensory integration), while younger adults demonstrated a significant increase in the magnitude of auditory-visual and auditory-somatosensory co-activation. This study provides first evidence in support of the facilitative effect of pairing somatosensory with visual stimuli in older adults.

  7. Bringing Art to Life through Multi-Sensory Tours

    ERIC Educational Resources Information Center

    Dodek, Wendy L.

    2012-01-01

    Learning occurs in myriad ways yet most art museums remain wedded to visual instruction. Adult visitors touring the galleries are offered audio guides or lecture style tours to complement the visual but are there other ways to enhance learning? This article reports on a case study that found that active, multi-sensory experiences in art museums…

  8. Attention and multisensory modulation argue against total encapsulation.

    PubMed

    de Haas, Benjamin; Schwarzkopf, Dietrich Samuel; Rees, Geraint

    2016-01-01

    Firestone & Scholl (F&S) postulate that vision proceeds without any direct interference from cognition. We argue that this view is extreme and not in line with the available evidence. Specifically, we discuss two well-established counterexamples: Attention directly affects core aspects of visual processing, and multisensory modulations of vision originate on multiple levels, some of which are unlikely to fall "within perception."

  9. Multisensory Speech Perception in Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Woynaroski, Tiffany G.; Kwakye, Leslie D.; Foss-Feig, Jennifer H.; Stevenson, Ryan A.; Stone, Wendy L.; Wallace, Mark T.

    2013-01-01

    This study examined unisensory and multisensory speech perception in 8-17 year old children with autism spectrum disorders (ASD) and typically developing controls matched on chronological age, sex, and IQ. Consonant-vowel syllables were presented in visual only, auditory only, matched audiovisual, and mismatched audiovisual ("McGurk")…

  10. Accelerating Early Language Development with Multi-Sensory Training

    ERIC Educational Resources Information Center

    Bjorn, Piia M.; Kakkuri, Irma; Karvonen, Pirkko; Leppanen, Paavo H. T.

    2012-01-01

    This paper reports the outcome of a multi-sensory intervention on infant language skills. A programme titled "Rhyming Game and Exercise Club", which included kinaesthetic-tactile mother-child rhyming games performed in natural joint attention situations, was intended to accelerate Finnish six- to eight-month-old infants' language development. The…

  11. The Multisensory Sound Lab: Sounds You Can See and Feel.

    ERIC Educational Resources Information Center

    Lederman, Norman; Hendricks, Paula

    1994-01-01

    A multisensory sound lab has been developed at the Model Secondary School for the Deaf (District of Columbia). A special floor allows vibrations to be felt, and a spectrum analyzer displays frequencies and harmonics visually. The lab is used for science education, auditory training, speech therapy, music and dance instruction, and relaxation…

  12. Early Visual Deprivation Alters Multisensory Processing in Peripersonal Space

    ERIC Educational Resources Information Center

    Collignon, Olivier; Charbonneau, Genevieve; Lassonde, Maryse; Lepore, Franco

    2009-01-01

    Multisensory peripersonal space develops in a maturational process that is thought to be influenced by early sensory experience. We investigated the role of vision in the effective development of audiotactile interactions in peripersonal space. Early blind (EB), late blind (LB) and sighted control (SC) participants were asked to lateralize…

  13. Please! Teach All of Me: Multisensory Activities for Preschoolers.

    ERIC Educational Resources Information Center

    Crawford, Jackie; Hanson, Joni; Gums, Marcia; Neys, Paula

    Most people, including children, have preferences for how they learn about the world. When these preferences are clearly noticeable, they may be thought of as sensory strengths. For some children, sensory strengths develop because of a weakness in another sensory area. For these children, multisensory instruction can be very helpful. Multisensory…

  14. Multiple Pathways to Self: A Multisensory Art Experience.

    ERIC Educational Resources Information Center

    Jensen, Sharon M.

    1997-01-01

    Reports on a multisensory intervention that combined art, music, and movement within a long-term care setting for Alzheimer's patients. Details the benefits derived by some of the participants who attended the sessions regularly. Many were able to retrieve memories, enjoy socialization, and have the opportunity for affective expression. (RJM)

  15. Multisensory Teaching of Basic Language Skills. Second Edition

    ERIC Educational Resources Information Center

    Birsh, Judith R., Ed.

    2005-01-01

    For students with dyslexia and other learning disabilities--and for their peers--creative teaching methods that use two or more senses can dramatically improve language skills and academic outcomes. That is why every current and future educator needs the second edition of this definitive guide to multisensory teaching. A core text for a variety of…

  16. Multisensory Teaching of Basic Language Skills. Third Edition

    ERIC Educational Resources Information Center

    Birsh, Judith R., Ed.

    2011-01-01

    As new research shows how effective systematic and explicit teaching of language-based skills is for students with learning disabilities--along with the added benefits of multisensory techniques--discover the latest on this popular teaching approach with the third edition of this bestselling textbook. Adopted by colleges and universities across…

  17. Multisensory Public Access Catalogs on CD-ROM.

    ERIC Educational Resources Information Center

    Harrison, Nancy; Murphy, Brower

    1987-01-01

    BiblioFile Intelligent Catalog is a CD-ROM-based public access catalog system which incorporates graphics and sound to provide a multisensory interface and artificial intelligence techniques to increase search precision. The system can be updated frequently and inexpensively by linking hard disk drives to CD-ROM optical drives. (MES)

  18. Evidence for Diminished Multisensory Integration in Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Stevenson, Ryan A.; Siemann, Justin K.; Woynaroski, Tiffany G.; Schneider, Brittany C.; Eberly, Haley E.; Camarata, Stephen M.; Wallace, Mark T.

    2014-01-01

    Individuals with autism spectrum disorders (ASD) exhibit alterations in sensory processing, including changes in the integration of information across the different sensory modalities. In the current study, we used the sound-induced flash illusion to assess multisensory integration in children with ASD and typically-developing (TD) controls.…

  19. Multisensory Speech Perception Without the Left Superior Temporal Sulcus

    PubMed Central

    Baum, Sarah H.; Martin, Randi C.; Hamilton, A. Cris; Beauchamp, Michael S.

    2012-01-01

    Converging evidence suggests that the left superior temporal sulcus (STS) is a critical site for multisensory integration of auditory and visual information during speech perception. We report a patient, SJ, who suffered a stroke that damaged the left tempo-parietal area, resulting in mild anomic aphasia. Structural MRI showed complete destruction of the left middle and posterior STS, as well as damage to adjacent areas in the temporal and parietal lobes. Surprisingly, SJ demonstrated preserved multisensory integration measured with two independent tests. First, she perceived the McGurk effect, an illusion that requires integration of auditory and visual speech. Second, her perception of morphed audiovisual speech with ambiguous auditory or visual information was significantly influenced by the opposing modality. To understand the neural basis for this preserved multisensory integration, blood-oxygen level dependent functional magnetic resonance imaging (BOLD fMRI) was used to examine brain responses to audiovisual speech in SJ and 23 healthy age-matched controls. In controls, bilateral STS activity was observed. In SJ, no activity was observed in the damaged left STS but in the right STS, more cortex was active in SJ than in any of the normal controls. Further, the amplitude of the BOLD response in right STS response to McGurk stimuli was significantly greater in SJ than in controls. The simplest explanation of these results is a reorganization of SJ's cortical language networks such that the right STS now subserves multisensory integration of speech. PMID:22634292

  20. Detection of Iberian ham aroma by a semiconductor multisensorial system.

    PubMed

    Otero, Laura; Horrillo, M A Carmen; García, María; Sayago, Isabel; Aleixandre, Manuel; Fernández, M A Jesús; Arés, Luis; Gutiérrez, Javier

    2003-11-01

    A semiconductor multisensorial system, based on tin oxide, to control the quality of dry-cured Iberian hams is described. Two types of ham (submitted to different drying temperatures) were selected. Good responses were obtained from the 12 elements forming the multisensor for different operating temperatures. Discrimination between the two types of ham was successfully realised through principal component analysis (PCA).

  1. Influences of Multisensory Experience on Subsequent Unisensory Processing

    PubMed Central

    Shams, Ladan; Wozny, David R.; Kim, Robyn; Seitz, Aaron

    2011-01-01

    Multisensory perception has been the focus of intense investigation in recent years. It is now well-established that crossmodal interactions are ubiquitous in perceptual processing and endow the system with improved precision, accuracy, processing speed, etc. While these findings have shed much light on principles and mechanisms of perception, ultimately it is not very surprising that multiple sources of information provides benefits in performance compared to a single source of information. Here, we argue that the more surprising recent findings are those showing that multisensory experience also influences the subsequent unisensory processing. For example, exposure to auditory–visual stimuli can change the way that auditory or visual stimuli are processed subsequently even in isolation. We review three sets of findings that represent three different types of learning ranging from perceptual learning, to sensory recalibration, to associative learning. In all these cases exposure to multisensory stimuli profoundly influences the subsequent unisensory processing. This diversity of phenomena may suggest that continuous modification of unisensory representations by multisensory relationships may be a general learning strategy employed by the brain. PMID:22028697

  2. Multisensory Emplaced Learning: Resituating Situated Learning in a Moving World

    ERIC Educational Resources Information Center

    Fors, Vaike; Backstrom, Asa; Pink, Sarah

    2013-01-01

    This article outlines the implications of a theory of "sensory-emplaced learning" for understanding the interrelationships between the embodied and environmental in learning processes. Understanding learning as multisensory and contingent within everyday place-events, this framework analytically describes how people establish themselves…

  3. Multisensory Emplaced Learning: Resituating Situated Learning in a Moving World

    ERIC Educational Resources Information Center

    Fors, Vaike; Backstrom, Asa; Pink, Sarah

    2013-01-01

    This article outlines the implications of a theory of "sensory-emplaced learning" for understanding the interrelationships between the embodied and environmental in learning processes. Understanding learning as multisensory and contingent within everyday place-events, this framework analytically describes how people establish themselves as…

  4. Altered Auditory and Multisensory Temporal Processing in Autism Spectrum Disorders

    PubMed Central

    Kwakye, Leslie D.; Foss-Feig, Jennifer H.; Cascio, Carissa J.; Stone, Wendy L.; Wallace, Mark T.

    2011-01-01

    Autism spectrum disorders (ASD) are characterized by deficits in social reciprocity and communication, as well as by repetitive behaviors and restricted interests. Unusual responses to sensory input and disruptions in the processing of both unisensory and multisensory stimuli also have been reported frequently. However, the specific aspects of sensory processing that are disrupted in ASD have yet to be fully elucidated. Recent published work has shown that children with ASD can integrate low-level audiovisual stimuli, but do so over an extended range of time when compared with typically developing (TD) children. However, the possible contributions of altered unisensory temporal processes to the demonstrated changes in multisensory function are yet unknown. In the current study, unisensory temporal acuity was measured by determining individual thresholds on visual and auditory temporal order judgment (TOJ) tasks, and multisensory temporal function was assessed through a cross-modal version of the TOJ task. Whereas no differences in thresholds for the visual TOJ task were seen between children with ASD and TD, thresholds were higher in ASD on the auditory TOJ task, providing preliminary evidence for impairment in auditory temporal processing. On the multisensory TOJ task, children with ASD showed performance improvements over a wider range of temporal intervals than TD children, reinforcing prior work showing an extended temporal window of multisensory integration in ASD. These findings contribute to a better understanding of basic sensory processing differences, which may be critical for understanding more complex social and cognitive deficits in ASD, and ultimately may contribute to more effective diagnostic and interventional strategies. PMID:21258617

  5. Affect differentially modulates brain activation in uni- and multisensory body-voice perception.

    PubMed

    Jessen, Sarah; Kotz, Sonja A

    2015-01-01

    Emotion perception naturally entails multisensory integration. It is also assumed that multisensory emotion perception is characterized by enhanced activation of brain areas implied in multisensory integration, such as the superior temporal gyrus and sulcus (STG/STS). However, most previous studies have employed designs and stimuli that preclude other forms of multisensory interaction, such as crossmodal prediction, leaving open the question whether classical integration is the only relevant process in multisensory emotion perception. Here, we used video clips containing emotional and neutral body and vocal expressions to investigate the role of crossmodal prediction in multisensory emotion perception. While emotional multisensory expressions increased activation in the bilateral fusiform gyrus (FFG), neutral expressions compared to emotional ones enhanced activation in the bilateral middle temporal gyrus (MTG) and posterior STS. Hence, while neutral stimuli activate classical multisensory areas, emotional stimuli invoke areas linked to unisensory visual processing. Emotional stimuli may therefore trigger a prediction of upcoming auditory information based on prior visual information. Such prediction may be stronger for highly salient emotional compared to less salient neutral information. Therefore, we suggest that multisensory emotion perception involves at least two distinct mechanisms; classical multisensory integration, as shown for neutral expressions, and crossmodal prediction, as evident for emotional expressions.

  6. Anthro-Centric Multisensory Interface for Vision Augmentation/Substitution (ACMI-VAS)

    DTIC Science & Technology

    2014-02-01

    AD_________________ Award Number: W81XWH-10-1-0084 TITLE: Anthro-Centric Multisensory Interface for Vision Augmentation/Substitution PRINCIPAL...Multisensory Interface for Vision Augmentation/ 5a. CONTRACT NUMBER Substitution (ACMI-VAS) 5b. GRANT NUMBER W81XWH-10-1-0084 5c. PROGRAM ELEMENT...SUPPLEMENTARY NOTES 14. ABSTRACT During year four of the Anthro-Centric Multisensory Interface Vision Augmentation/Substitution (ACMI-VAS) project, the

  7. Unisensory processing and multisensory integration in schizophrenia: a high-density electrical mapping study.

    PubMed

    Stone, David B; Urrea, Laura J; Aine, Cheryl J; Bustillo, Juan R; Clark, Vincent P; Stephen, Julia M

    2011-10-01

    In real-world settings, information from multiple sensory modalities is combined to form a complete, behaviorally salient percept - a process known as multisensory integration. While deficits in auditory and visual processing are often observed in schizophrenia, little is known about how multisensory integration is affected by the disorder. The present study examined auditory, visual, and combined audio-visual processing in schizophrenia patients using high-density electrical mapping. An ecologically relevant task was used to compare unisensory and multisensory evoked potentials from schizophrenia patients to potentials from healthy normal volunteers. Analysis of unisensory responses revealed a large decrease in the N100 component of the auditory-evoked potential, as well as early differences in the visual-evoked components in the schizophrenia group. Differences in early evoked responses to multisensory stimuli were also detected. Multisensory facilitation was assessed by comparing the sum of auditory and visual evoked responses to the audio-visual evoked response. Schizophrenia patients showed a significantly greater absolute magnitude response to audio-visual stimuli than to summed unisensory stimuli when compared to healthy volunteers, indicating significantly greater multisensory facilitation in the patient group. Behavioral responses also indicated increased facilitation from multisensory stimuli. The results represent the first report of increased multisensory facilitation in schizophrenia and suggest that, although unisensory deficits are present, compensatory mechanisms may exist under certain conditions that permit improved multisensory integration in individuals afflicted with the disorder.

  8. Multisensory brain mechanisms of bodily self-consciousness.

    PubMed

    Blanke, Olaf

    2012-07-18

    Recent research has linked bodily self-consciousness to the processing and integration of multisensory bodily signals in temporoparietal, premotor, posterior parietal and extrastriate cortices. Studies in which subjects receive ambiguous multisensory information about the location and appearance of their own body have shown that these brain areas reflect the conscious experience of identifying with the body (self-identification (also known as body-ownership)), the experience of where 'I' am in space (self-location) and the experience of the position from where 'I' perceive the world (first-person perspective). Along with phenomena of altered states of self-consciousness in neurological patients and electrophysiological data from non-human primates, these findings may form the basis for a neurobiological model of bodily self-consciousness.

  9. Auditory, Somatosensory, and Multisensory Insular Cortex in the Rat

    PubMed Central

    Rodgers, Krista M.; Benison, Alexander M.; Klein, Andrea

    2008-01-01

    Compared with other areas of the forebrain, the function of insular cortex is poorly understood. This study examined the unisensory and multisensory function of the rat insula using high-resolution, whole-hemisphere, epipial evoked potential mapping. We found the posterior insula to contain distinct auditory and somatotopically organized somatosensory fields with an interposed and overlapping region capable of integrating these sensory modalities. Unisensory and multisensory responses were uninfluenced by complete lesioning of primary and secondary auditory and somatosensory cortices, suggesting a high degree of parallel afferent input from the thalamus. In light of the established connections of the posterior insula with the amygdala, we propose that integration of auditory and somatosensory modalities reported here may play a role in auditory fear conditioning. PMID:18424777

  10. Anthro-Centric Multisensory Interface for Vision Augmentation/Substitution

    DTIC Science & Technology

    2013-02-01

    for Vision Augmentation/Substitution PRINCIPAL INVESTIGATOR: Anil Raj, M.D...Multisensory Interface for Vision Augmentation/Substitution 5b. GRANT NUMBER W81XWH-10-1-0084 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...trauma. Sudden loss of vision can overwhelm a previously healthy individual’s ability to interact with the world, adversely impact the individual’s

  11. Adaptive multifunctional composites

    NASA Astrophysics Data System (ADS)

    Wang, Ya; Inman, Daniel J.

    2013-05-01

    The adaptive multifunctional composite structure studied here is to address two issues remaining in lightweight structural composites required by many engineering applications. The first is to add additional functionality to multifunctional composites and the second is to provide adaptive damping in structures that cover a wide range of frequencies and temperatures. Because of its potential for practical payoffs, passive structural damping can find wide application through the use of high-damping viscoelastic polymers or elastomers. However, all passive damping using these damping materials suffer from failing at certain temperatures and in certain frequency ranges. The extreme environments often seen by engineering systems provide high temperature, which is exactly where damping levels in structures reduce causing unacceptable vibrations. In addition, as loading frequencies reduce damping levels also fall off, and many loads experienced by large structures are low frequency. The proposed research addresses increasing the range of effectiveness of damping by addressing the temperature and frequency dependence of material damping by using a multifunctional composite system containing an active element. Previous research has yielded a finite element model of linear viscoelastic material and structural behavior that captures characteristic frequency-dependent behavior, continuing research has addressed the accommodation of temperature dependence, and the examination of the new concept of `electronic damping' or `e-damping'. The resulting modeling approach is validated through experimental validation.

  12. Attention modeled as information in learning multisensory integration.

    PubMed

    Bauer, Johannes; Magg, Sven; Wermter, Stefan

    2015-05-01

    Top-down cognitive processes affect the way bottom-up cross-sensory stimuli are integrated. In this paper, we therefore extend a successful previous neural network model of learning multisensory integration in the superior colliculus (SC) by top-down, attentional input and train it on different classes of cross-modal stimuli. The network not only learns to integrate cross-modal stimuli, but the model also reproduces neurons specializing in different combinations of modalities as well as behavioral and neurophysiological phenomena associated with spatial and feature-based attention. Importantly, we do not provide the model with any information about which input neurons are sensory and which are attentional. If the basic mechanisms of our model-self-organized learning of input statistics and divisive normalization-play a major role in the ontogenesis of the SC, then this work shows that these mechanisms suffice to explain a wide range of aspects both of bottom-up multisensory integration and the top-down influence on multisensory integration.

  13. Neuroscience robotics to investigate multisensory integration and bodily awareness.

    PubMed

    Duenas, J; Chapuis, D; Pfeiffer, C; Martuzzi, R; Ionta, S; Blanke, O; Gassert, R

    2011-01-01

    Humans experience the self as localized within their body. This aspect of bodily self-consciousness can be experimentally manipulated by exposing individuals to conflicting multisensory input, or can be abnormal following focal brain injury. Recent technological developments helped to unravel some of the mechanisms underlying multisensory integration and self-location, but the neural underpinnings are still under investigation, and the manual application of stimuli resulted in large variability difficult to control. This paper presents the development and evaluation of an MR-compatible stroking device capable of presenting moving tactile stimuli to both legs and the back of participants lying on a scanner bed while acquiring functional neuroimaging data. The platform consists of four independent stroking devices with a travel of 16-20 cm and a maximum stroking velocity of 15 cm/s, actuated over non-magnetic ultrasonic motors. Complemented with virtual reality, this setup provides a unique research platform allowing to investigate multisensory integration and its effects on self-location under well-controlled experimental conditions. The MR-compatibility of the system was evaluated in both a 3 and a 7 Tesla scanner and showed negligible interference with brain imaging. In a preliminary study using a prototype device with only one tactile stimulator, fMRI data acquired on 12 healthy participants showed visuo-tactile synchrony-related and body-specific modulations of the brain activity in bilateral temporoparietal cortex.

  14. Video game players show more precise multisensory temporal processing abilities.

    PubMed

    Donohue, Sarah E; Woldorff, Marty G; Mitroff, Stephen R

    2010-05-01

    Recent research has demonstrated enhanced visual attention and visual perception in individuals with extensive experience playing action video games. These benefits manifest in several realms, but much remains unknown about the ways in which video game experience alters perception and cognition. In the present study, we examined whether video game players' benefits generalize beyond vision to multisensory processing by presenting auditory and visual stimuli within a short temporal window to video game players and non-video game players. Participants performed two discrimination tasks, both of which revealed benefits for video game players: In a simultaneity judgment task, video game players were better able to distinguish whether simple visual and auditory stimuli occurred at the same moment or slightly offset in time, and in a temporal-order judgment task, they revealed an enhanced ability to determine the temporal sequence of multisensory stimuli. These results suggest that people with extensive experience playing video games display benefits that extend beyond the visual modality to also impact multisensory processing.

  15. Verbal and novel multisensory associative learning in adults

    PubMed Central

    Crewther, Sheila G

    2013-01-01

    To date, few studies have focused on the behavioural differences between the learning of multisensory auditory-visual and intra-modal associations. More specifically, the relative benefits of novel auditory-visual and verbal-visual associations for learning have not been directly compared. In Experiment 1, 20 adult volunteers completed three paired associate learning tasks: non-verbal novel auditory-visual (novel-AV), verbal-visual (verbal-AV; using pseudowords), and visual-visual (shape-VV). Participants were directed to make a motor response to matching novel and arbitrarily related stimulus pairs. Feedback was provided to facilitate trial and error learning. The results of Signal Detection Theory analyses suggested a multisensory enhancement of learning, with significantly higher discriminability measures (d-prime) in both the novel-AV and verbal-AV tasks than the shape-VV task. Motor reaction times were also significantly faster during the verbal-AV task than during the non-verbal learning tasks.  Experiment 2 (n = 12) used a forced-choice discrimination paradigm to assess whether a difference in unisensory stimulus discriminability could account for the learning trends in Experiment 1. Participants were significantly slower at discriminating unisensory pseudowords than the novel sounds and visual shapes, which was notable given that these stimuli produced superior learning. Together the findings suggest that verbal information has an added enhancing effect on multisensory associative learning in adults PMID:24627770

  16. Sensorimotor synchronization with audio-visual stimuli: limited multisensory integration.

    PubMed

    Armstrong, Alan; Issartel, Johann

    2014-11-01

    Understanding how we synchronize our actions with stimuli from different sensory modalities plays a central role in helping to establish how we interact with our multisensory environment. Recent research has shown better performance with multisensory over unisensory stimuli; however, the type of stimuli used has mainly been auditory and tactile. The aim of this article was to expand our understanding of sensorimotor synchronization with multisensory audio-visual stimuli and compare these findings to their individual unisensory counterparts. This research also aims to assess the role of spatio-temporal structure for each sensory modality. The visual and/or auditory stimuli had either temporal or spatio-temporal information available and were presented to the participants in unimodal and bimodal conditions. Globally, the performance was significantly better for the bimodal compared to the unimodal conditions; however, this benefit was limited to only one of the bimodal conditions. In terms of the unimodal conditions, the level of synchronization with visual stimuli was better than auditory, and while there was an observed benefit with the spatio-temporal compared to temporal visual stimulus, this was not replicated with the auditory stimulus.

  17. Multisensory integration in children with Developmental Coordination Disorder.

    PubMed

    Coats, R O A; Britten, L; Utley, A; Astill, S L

    2015-10-01

    This study examines how multisensory stimuli affect the performance of children with Developmental Coordination Disorder (DCD) on a choice reaction time (CRT) task. Ten children with DCD, identified using the Movement Assessment Battery for Children-2, aged 7-10 years (4F, M=8 y 3 m, SD=17 m) and 10 typically developing peers (TDC) (5F, M=8 y 4 m, SD=17 m) reached to unimodal (auditory (AO), visual (VO)) and bimodal (audiovisual (AV)) stimuli at one of three target locations. A multisensory (AV) stimulus reduced RTs for both groups (p<0.001, η(2)=0.36). While the children with DCD had a longer RT in all conditions, the AV stimulus produced RTs in children with DCD (494 ms) that were equivalent to those produced by the TDC to the VO stimulus (493 ms). Movement Time (DCD=486 ms; TDC=434 ms) and Path Length (DCD=25.6 cm; TDC=24.2 cm) were longer in children with DCD compared to TDC as expected (p<0.05). Only the TDC benefited from the AV information for movement control, as deceleration time of the dominant hand was seen to decrease when moving to an AV stimulus (p<0.05). Overall, data shows children with DCD do benefit from a bimodal stimulus to plan their movement, but do not for movement control. Further research is required to understand if this is a result of impaired multisensory integration.

  18. Multisensory perceptual learning is dependent upon task difficulty.

    PubMed

    De Niear, Matthew A; Koo, Bonhwang; Wallace, Mark T

    2016-11-01

    There has been a growing interest in developing behavioral tasks to enhance temporal acuity as recent findings have demonstrated changes in temporal processing in a number of clinical conditions. Prior research has demonstrated that perceptual training can enhance temporal acuity both within and across different sensory modalities. Although certain forms of unisensory perceptual learning have been shown to be dependent upon task difficulty, this relationship has not been explored for multisensory learning. The present study sought to determine the effects of task difficulty on multisensory perceptual learning. Prior to and following a single training session, participants completed a simultaneity judgment (SJ) task, which required them to judge whether a visual stimulus (flash) and auditory stimulus (beep) presented in synchrony or at various stimulus onset asynchronies (SOAs) occurred synchronously or asynchronously. During the training session, participants completed the same SJ task but received feedback regarding the accuracy of their responses. Participants were randomly assigned to one of three levels of difficulty during training: easy, moderate, and hard, which were distinguished based on the SOAs used during training. We report that only the most difficult (i.e., hard) training protocol enhanced temporal acuity. We conclude that perceptual training protocols for enhancing multisensory temporal acuity may be optimized by employing audiovisual stimuli for which it is difficult to discriminate temporal synchrony from asynchrony.

  19. Single-trial multisensory memories affect later auditory and visual object discrimination.

    PubMed

    Thelen, Antonia; Talsma, Durk; Murray, Micah M

    2015-05-01

    Multisensory memory traces established via single-trial exposures can impact subsequent visual object recognition. This impact appears to depend on the meaningfulness of the initial multisensory pairing, implying that multisensory exposures establish distinct object representations that are accessible during later unisensory processing. Multisensory contexts may be particularly effective in influencing auditory discrimination, given the purportedly inferior recognition memory in this sensory modality. The possibility of this generalization and the equivalence of effects when memory discrimination was being performed in the visual vs. auditory modality were at the focus of this study. First, we demonstrate that visual object discrimination is affected by the context of prior multisensory encounters, replicating and extending previous findings by controlling for the probability of multisensory contexts during initial as well as repeated object presentations. Second, we provide the first evidence that single-trial multisensory memories impact subsequent auditory object discrimination. Auditory object discrimination was enhanced when initial presentations entailed semantically congruent multisensory pairs and was impaired after semantically incongruent multisensory encounters, compared to sounds that had been encountered only in a unisensory manner. Third, the impact of single-trial multisensory memories upon unisensory object discrimination was greater when the task was performed in the auditory vs. visual modality. Fourth, there was no evidence for correlation between effects of past multisensory experiences on visual and auditory processing, suggestive of largely independent object processing mechanisms between modalities. We discuss these findings in terms of the conceptual short term memory (CSTM) model and predictive coding. Our results suggest differential recruitment and modulation of conceptual memory networks according to the sensory task at hand.

  20. Multisensory interactions in the depth plane in front and rear space: a review.

    PubMed

    Van der Stoep, N; Nijboer, T C W; Van der Stigchel, S; Spence, C

    2015-04-01

    In this review, we evaluate the neurophysiological, neuropsychological, and psychophysical evidence relevant to the claim that multisensory information is processed differently depending on the region of space in which it happens to be presented. We discuss how the majority of studies of multisensory interactions in the depth plane that have been conducted to date have focused on visuotactile and audiotactile interactions in frontal peripersonal space and underline the importance of such multisensory interactions in defining peripersonal space. Based on our review of studies of multisensory interactions in depth, we question the extent to which peri- and extra-personal space (both frontal and rear) are characterized by differences in multisensory interactions (as evidenced by multisensory stimuli producing a different behavioral outcome as compared to unisensory stimulation). In addition to providing an overview of studies of multisensory interactions in different regions of space, our goal in writing this review has been to demonstrate that the various kinds of multisensory interactions that have been documented may follow very similar organizing principles. Multisensory interactions in depth that involve tactile stimuli are constrained by the fact that such stimuli typically need to contact the skin surface. Therefore, depth-related preferences of multisensory interactions involving touch can largely be explained in terms of their spatial alignment in depth and their alignment with the body. As yet, no such depth-related asymmetry has been observed in the case of audiovisual interactions. We therefore suggest that the spatial boundary of peripersonal space and the enhanced audiotactile and visuotactile interactions that occur in peripersonal space can be explained in terms of the particular spatial alignment of stimuli from different modalities with the body and that they likely reflect the result of prior multisensory experience.

  1. Cell Nucleus-Targeting Zwitterionic Carbon Dots

    PubMed Central

    Jung, Yun Kyung; Shin, Eeseul; Kim, Byeong-Su

    2015-01-01

    An innovative nucleus-targeting zwitterionic carbon dot (CD) vehicle has been developed for anticancer drug delivery and optical monitoring. The zwitterionic functional groups of the CDs introduced by a simple one-step synthesis using β-alanine as a passivating and zwitterionic ligand allow cytoplasmic uptake and subsequent nuclear translocation of the CDs. Moreover, multicolor fluorescence improves the accuracy of the CDs as an optical code. The CD-based drug delivery system constructed by non-covalent grafting of doxorubicin, exhibits superior antitumor efficacy owing to enhanced nuclear delivery in vitro and tumor accumulation in vivo, resulting in highly effective tumor growth inhibition. Since the zwitterionic CDs are highly biocompatible and effectively translocated into the nucleus, it provides a compelling solution to a multifunctional nanoparticle for substantially enhanced nuclear uptake of drugs and optical monitoring of translocation. PMID:26689549

  2. Cell Nucleus-Targeting Zwitterionic Carbon Dots.

    PubMed

    Jung, Yun Kyung; Shin, Eeseul; Kim, Byeong-Su

    2015-12-22

    An innovative nucleus-targeting zwitterionic carbon dot (CD) vehicle has been developed for anticancer drug delivery and optical monitoring. The zwitterionic functional groups of the CDs introduced by a simple one-step synthesis using β-alanine as a passivating and zwitterionic ligand allow cytoplasmic uptake and subsequent nuclear translocation of the CDs. Moreover, multicolor fluorescence improves the accuracy of the CDs as an optical code. The CD-based drug delivery system constructed by non-covalent grafting of doxorubicin, exhibits superior antitumor efficacy owing to enhanced nuclear delivery in vitro and tumor accumulation in vivo, resulting in highly effective tumor growth inhibition. Since the zwitterionic CDs are highly biocompatible and effectively translocated into the nucleus, it provides a compelling solution to a multifunctional nanoparticle for substantially enhanced nuclear uptake of drugs and optical monitoring of translocation.

  3. Binding of Sights and Sounds: Age-Related Changes in Multisensory Temporal Processing

    ERIC Educational Resources Information Center

    Hillock, Andrea R.; Powers, Albert R.; Wallace, Mark T.

    2011-01-01

    We live in a multisensory world and one of the challenges the brain is faced with is deciding what information belongs together. Our ability to make assumptions about the relatedness of multisensory stimuli is partly based on their temporal and spatial relationships. Stimuli that are proximal in time and space are likely to be bound together by…

  4. Individual Differences in the Multisensory Temporal Binding Window Predict Susceptibility to Audiovisual Illusions

    ERIC Educational Resources Information Center

    Stevenson, Ryan A.; Zemtsov, Raquel K.; Wallace, Mark T.

    2012-01-01

    Human multisensory systems are known to bind inputs from the different sensory modalities into a unified percept, a process that leads to measurable behavioral benefits. This integrative process can be observed through multisensory illusions, including the McGurk effect and the sound-induced flash illusion, both of which demonstrate the ability of…

  5. The Race that Precedes Coactivation: Development of Multisensory Facilitation in Children

    ERIC Educational Resources Information Center

    Barutchu, Ayla; Crewther, David P.; Crewther, Sheila G.

    2009-01-01

    Rationale: The facilitating effect of multisensory integration on motor responses in adults is much larger than predicted by race-models and is in accordance with the idea of coactivation. However, the development of multisensory facilitation of endogenously driven motor processes and its relationship to the development of complex cognitive skills…

  6. High energy nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

    Wosiek, B.

    1986-01-01

    Experimental results on high energy nucleus-nucleus interactions are presented. The data are discussed within the framework of standard super-position models and from the point-of-view of the possible formation of new states of matter in heavy ion collisions.

  7. Templated biomimetic multifunctional coatings

    NASA Astrophysics Data System (ADS)

    Sun, Chih-Hung; Gonzalez, Adriel; Linn, Nicholas C.; Jiang, Peng; Jiang, Bin

    2008-02-01

    We report a bioinspired templating technique for fabricating multifunctional optical coatings that mimic both unique functionalities of antireflective moth eyes and superhydrophobic cicada wings. Subwavelength-structured fluoropolymer nipple arrays are created by a soft-lithography-like process. The utilization of fluoropolymers simultaneously enhances the antireflective performance and the hydrophobicity of the replicated films. The specular reflectivity matches the optical simulation using a thin-film multilayer model. The dependence of the size and the crystalline ordering of the replicated nipples on the resulting antireflective properties have also been investigated by experiment and modeling. These biomimetic materials may find important technological application in self-cleaning antireflection coatings.

  8. Multifunctional reference electrode

    DOEpatents

    Redey, L.; Vissers, D.R.

    1981-12-30

    A multifunctional, low mass reference electrode of a nickel tube, thermocouple means inside the nickel tube electrically insulated therefrom for measuring the temperature thereof, a housing surrounding the nickel tube, an electrolyte having a fixed sulfide ion activity between the housing and the outer surface of the nickel tube forming the nickel/nickel sulfide/sulfide half-cell are described. An ion diffusion barrier is associated with the housing in contact with the electrolyte. Also disclosed is a cell using the reference electrode to measure characteristics of a working electrode.

  9. Multifunctional reference electrode

    DOEpatents

    Redey, Laszlo; Vissers, Donald R.

    1983-01-01

    A multifunctional, low mass reference electrode of a nickel tube, thermocouple means inside the nickel tube electrically insulated therefrom for measuring the temperature thereof, a housing surrounding the nickel tube, an electrolyte having a fixed sulfide ion activity between the housing and the outer surface of the nickel tube forming the nickel/nickel sulfide/sulfide half-cell. An ion diffusion barrier is associated with the housing in contact with the electrolyte. Also disclosed is a cell using the reference electrode to measure characteristics of a working electrode.

  10. Learning Multisensory Integration and Coordinate Transformation via Density Estimation

    PubMed Central

    Sabes, Philip N.

    2013-01-01

    Sensory processing in the brain includes three key operations: multisensory integration—the task of combining cues into a single estimate of a common underlying stimulus; coordinate transformations—the change of reference frame for a stimulus (e.g., retinotopic to body-centered) effected through knowledge about an intervening variable (e.g., gaze position); and the incorporation of prior information. Statistically optimal sensory processing requires that each of these operations maintains the correct posterior distribution over the stimulus. Elements of this optimality have been demonstrated in many behavioral contexts in humans and other animals, suggesting that the neural computations are indeed optimal. That the relationships between sensory modalities are complex and plastic further suggests that these computations are learned—but how? We provide a principled answer, by treating the acquisition of these mappings as a case of density estimation, a well-studied problem in machine learning and statistics, in which the distribution of observed data is modeled in terms of a set of fixed parameters and a set of latent variables. In our case, the observed data are unisensory-population activities, the fixed parameters are synaptic connections, and the latent variables are multisensory-population activities. In particular, we train a restricted Boltzmann machine with the biologically plausible contrastive-divergence rule to learn a range of neural computations not previously demonstrated under a single approach: optimal integration; encoding of priors; hierarchical integration of cues; learning when not to integrate; and coordinate transformation. The model makes testable predictions about the nature of multisensory representations. PMID:23637588

  11. Multi-functional windows

    NASA Astrophysics Data System (ADS)

    Nag, Nagendra; Goldman, Lee M.; Balasubramanian, Sreeram; Sastri, Suri

    2013-06-01

    The requirements for modern aircraft are driving the need for conformal windows for future sensor systems. However, limitations on optical systems and the physical properties of optically transparent materials currently limit the geometry of existing windows and window assemblies to faceted assemblies of flat windows held in weight bearing frames. Novel material systems will have to be developed which combine different materials (e.g. ductile metals with transparent ceramics) into structures that combine transparency with structural integrity. Surmet's demonstrated ability to produce novel transparent ceramic/metal structures will allow us to produce such structures in the types of conformal shapes required for future aircraft applications. Furthermore, the ability to incorporate transparencies into such structures also holds out the promise of creating multi-functional windows which provide a broad range of capabilities that might include RF antennas and de-icing in addition to transparency. Recent results in this area will be presented.

  12. Multisensory interactions in early evoked brain activity follow the principle of inverse effectiveness.

    PubMed

    Senkowski, Daniel; Saint-Amour, Dave; Höfle, Marion; Foxe, John J

    2011-06-15

    A major determinant of multisensory integration, derived from single-neuron studies in animals, is the principle of inverse effectiveness (IE), which describes the phenomenon whereby maximal multisensory response enhancements occur when the constituent unisensory stimuli are minimally effective in evoking responses. Human behavioral studies, which have shown that multisensory interactions are strongest when stimuli are low in intensity are in agreement with the IE principle, but the neurophysiologic basis for this finding is unknown. In this high-density electroencephalography (EEG) study, we examined effects of stimulus intensity on multisensory audiovisual processing in event-related potentials (ERPs) and response time (RT) facilitation in the bisensory redundant target effect (RTE). The RTE describes that RTs are faster for bisensory redundant targets than for the respective unisensory targets. Participants were presented with semantically meaningless unisensory auditory, unisensory visual and bisensory audiovisual stimuli of low, middle and high intensity, while they were instructed to make a speeded button response when a stimulus in either modality was presented. Behavioral data showed that the RTE exceeded predictions on the basis of probability summations of unisensory RTs, indicative of integrative multisensory processing, but only for low intensity stimuli. Paralleling this finding, multisensory interactions in short latency (40-60ms) ERPs with a left posterior and right anterior topography were found particularly for stimuli with low intensity. Our findings demonstrate that the IE principle is applicable to early multisensory processing in humans.

  13. Ludic content in multisensory stimulation environments: an exploratory study about practice in Portugal.

    PubMed

    Castelhano, Nuno; Silva, Fabiana; Rezende, Márcia; Roque, Licínio; Magalhães, Lívia

    2013-09-01

    This article aims to document the use of multisensory stimulation environments and its related perceptions, concerning ludic content, play and the computer-mediated ludic activity, from the perspective of professionals organizing and delivering therapeutic activities in these spaces with children with developmental disabilities, in Portugal. Face-to-face open interviews with 12 professionals working in multisensory stimulation environments, selected by convenience criteria, were individually recorded, transcribed and submitted to content analysis. Three main themes emerged from the data: multisensory stimulation environments offer multiple possibilities for intervention, play is part of the intervention in multisensory environments and the computer-mediated ludic experience is perceived as useful for intervention. Data suggest that multisensory stimulation environments are used as versatile spaces, both considered and explored by the interviewed professionals in its ludic potential. This fact can renew the interest in multisensory environments, in particular for the area of play in Occupational Therapy, in which the use of the computer-mediated ludic experience is a recognized possibility. Limitations of this study are associated to the level of representativeness of the interviews in relation to the diverse universe of professionals using multisensory environments. The method for collecting data is also highly sensitive to the influence of the interviewer.

  14. The multisensory body revealed through its cast shadows

    PubMed Central

    Pavani, Francesco; Galfano, Giovanni

    2015-01-01

    One key issue when conceiving the body as a multisensory object is how the cognitive system integrates visible instances of the self and other bodies with one’s own somatosensory processing, to achieve self-recognition and body ownership. Recent research has strongly suggested that shadows cast by our own body have a special status for cognitive processing, directing attention to the body in a fast and highly specific manner. The aim of the present article is to review the most recent scientific contributions addressing how body shadows affect both sensory/perceptual and attentional processes. The review examines three main points: (1) body shadows as a special window to investigate the construction of multisensory body perception; (2) experimental paradigms and related findings; (3) open questions and future trajectories. The reviewed literature suggests that shadows cast by one’s own body promote binding between personal and extrapersonal space and elicit automatic orienting of attention toward the body-part casting the shadow. Future research should address whether the effects exerted by body shadows are similar to those observed when observers are exposed to other visual instances of their body. The results will further clarify the processes underlying the merging of vision and somatosensation when creating body representations. PMID:26042079

  15. Multisensory cueing for enhancing orientation information during flight.

    PubMed

    Albery, William B

    2007-05-01

    The U.S. Air Force still regards spatial disorientation (SD) and loss of situational awareness (SA) as major contributing factors in operational Class A aircraft mishaps ($1M in aircraft loss and/or pilot fatality). Air Force Safety Agency data show 71 Class A SD mishaps from 1991-2004 in both fixed and rotary-wing aircraft. These mishaps resulted in 62 fatalities and an aircraft cost of over $2.OB. These losses account for 21 % of the USAF's Class A mishaps during that 14-yr period. Even non-mishap SD events negatively impact aircrew performance and reduce mission effectiveness. A multisensory system has been developed called the Spatial Orientation Retention Device (SORD) to enhance the aircraft attitude information to the pilot. SORD incorporates multisensory aids including helmet mounted symbology and tactile and audio cues. SORD has been prototyped and demonstrated in the Air Force Research Laboratory at Wright-Patterson AFB, OH. The technology has now been transitioned to a Rotary Wing Brownout program. This paper discusses the development of SORD and a potential application, including an augmented cognition application. Unlike automatic ground collision avoidance systems, SORD does not take over the aircraft if a pre-set altitude is broached by the pilot; rather, SORD provides complementary attitude cues to the pilot via the tactile, audio, and visual systems that allow the pilot to continue flying through disorienting conditions.

  16. Cortical hierarchies perform Bayesian causal inference in multisensory perception.

    PubMed

    Rohe, Tim; Noppeney, Uta

    2015-02-01

    To form a veridical percept of the environment, the brain needs to integrate sensory signals from a common source but segregate those from independent sources. Thus, perception inherently relies on solving the "causal inference problem." Behaviorally, humans solve this problem optimally as predicted by Bayesian Causal Inference; yet, the underlying neural mechanisms are unexplored. Combining psychophysics, Bayesian modeling, functional magnetic resonance imaging (fMRI), and multivariate decoding in an audiovisual spatial localization task, we demonstrate that Bayesian Causal Inference is performed by a hierarchy of multisensory processes in the human brain. At the bottom of the hierarchy, in auditory and visual areas, location is represented on the basis that the two signals are generated by independent sources (= segregation). At the next stage, in posterior intraparietal sulcus, location is estimated under the assumption that the two signals are from a common source (= forced fusion). Only at the top of the hierarchy, in anterior intraparietal sulcus, the uncertainty about the causal structure of the world is taken into account and sensory signals are combined as predicted by Bayesian Causal Inference. Characterizing the computational operations of signal interactions reveals the hierarchical nature of multisensory perception in human neocortex. It unravels how the brain accomplishes Bayesian Causal Inference, a statistical computation fundamental for perception and cognition. Our results demonstrate how the brain combines information in the face of uncertainty about the underlying causal structure of the world.

  17. Perceptual learning shapes multisensory causal inference via two distinct mechanisms.

    PubMed

    McGovern, David P; Roudaia, Eugenie; Newell, Fiona N; Roach, Neil W

    2016-04-19

    To accurately represent the environment, our brains must integrate sensory signals from a common source while segregating those from independent sources. A reasonable strategy for performing this task is to restrict integration to cues that coincide in space and time. However, because multisensory signals are subject to differential transmission and processing delays, the brain must retain a degree of tolerance for temporal discrepancies. Recent research suggests that the width of this 'temporal binding window' can be reduced through perceptual learning, however, little is known about the mechanisms underlying these experience-dependent effects. Here, in separate experiments, we measure the temporal and spatial binding windows of human participants before and after training on an audiovisual temporal discrimination task. We show that training leads to two distinct effects on multisensory integration in the form of (i) a specific narrowing of the temporal binding window that does not transfer to spatial binding and (ii) a general reduction in the magnitude of crossmodal interactions across all spatiotemporal disparities. These effects arise naturally from a Bayesian model of causal inference in which learning improves the precision of audiovisual timing estimation, whilst concomitantly decreasing the prior expectation that stimuli emanate from a common source.

  18. Crocodylians evolved scattered multi-sensory micro-organs

    PubMed Central

    2013-01-01

    Background During their evolution towards a complete life cycle on land, stem reptiles developed both an impermeable multi-layered keratinized epidermis and skin appendages (scales) providing mechanical, thermal, and chemical protection. Previous studies have demonstrated that, despite the presence of a particularly armored skin, crocodylians have exquisite mechanosensory abilities thanks to the presence of small integumentary sensory organs (ISOs) distributed on postcranial and/or cranial scales. Results Here, we analyze and compare the structure, innervation, embryonic morphogenesis and sensory functions of postcranial, cranial, and lingual sensory organs of the Nile crocodile (Crocodylus niloticus) and the spectacled caiman (Caiman crocodilus). Our molecular analyses indicate that sensory neurons of crocodylian ISOs express a large repertoire of transduction channels involved in mechano-, thermo-, and chemosensory functions, and our electrophysiological analyses confirm that each ISO exhibits a combined sensitivity to mechanical, thermal and pH stimuli (but not hyper-osmotic salinity), making them remarkable multi-sensorial micro-organs with no equivalent in the sensory systems of other vertebrate lineages. We also show that ISOs all exhibit similar morphologies and modes of development, despite forming at different stages of scale morphogenesis across the body. Conclusions The ancestral vertebrate diffused sensory system of the skin was transformed in the crocodylian lineages into an array of discrete multi-sensory micro-organs innervated by multiple pools of sensory neurons. This discretization of skin sensory expression sites is unique among vertebrates and allowed crocodylians to develop a highly-armored, but very sensitive, skin. PMID:23819918

  19. A perspective on multisensory integration and rapid perturbation responses.

    PubMed

    Cluff, Tyler; Crevecoeur, Frédéric; Scott, Stephen H

    2015-05-01

    In order to perform accurate movements, the nervous system must transform sensory feedback into motor commands that compensate for errors caused by motor variability and external disturbances. Recent studies focusing on the importance of sensory feedback in motor control have illustrated that the brain generates highly flexible responses to visual perturbations (hand-cursor or target jumps), or following mechanical loads applied to the limb. These parallel approaches have emphasized sophisticated, goal-directed feedback control, but also reveal that flexible perturbation responses are expressed at different latencies depending on what sensory system is engaged by the perturbation. Across studies, goal-directed visuomotor responses consistently emerge in muscle activity ∼100ms after a perturbation, while mechanical perturbations evoke goal-directed muscle responses in as little as ∼60ms (long-latency responses). We discuss the limitation of current models of multisensory integration in light of these asynchronous processing delays, and suggest that understanding how the brain performs real-time multisensory integration is an open question for future studies.

  20. A cellular mechanism for inverse effectiveness in multisensory integration

    PubMed Central

    Truszkowski, Torrey LS; Carrillo, Oscar A; Bleier, Julia; Ramirez-Vizcarrondo, Carolina M; Felch, Daniel L; McQuillan, Molly; Truszkowski, Christopher P; Khakhalin, Arseny S; Aizenman, Carlos D

    2017-01-01

    To build a coherent view of the external world, an organism needs to integrate multiple types of sensory information from different sources, a process known as multisensory integration (MSI). Previously, we showed that the temporal dependence of MSI in the optic tectum of Xenopus laevis tadpoles is mediated by the network dynamics of the recruitment of local inhibition by sensory input (Felch et al., 2016). This was one of the first cellular-level mechanisms described for MSI. Here, we expand this cellular level view of MSI by focusing on the principle of inverse effectiveness, another central feature of MSI stating that the amount of multisensory enhancement observed inversely depends on the size of unisensory responses. We show that non-linear summation of crossmodal synaptic responses, mediated by NMDA-type glutamate receptor (NMDARs) activation, form the cellular basis for inverse effectiveness, both at the cellular and behavioral levels. DOI: http://dx.doi.org/10.7554/eLife.25392.001 PMID:28315524

  1. A study on the effect of multisensory stimulation in behaving rats.

    PubMed

    Semprini, Marianna; Boi, Fabio; Tucci, Valter; Vato, Alessandro

    2016-08-01

    This study explored the psychophysical effects of intracortical microstimulation (ICMS) coupled to auditory stimulation during a behavioral detection task in rats. ICMS directed to the sensory areas of the cortex can be instrumental in facilitating operant conditioning behavior. Moreover, multisensory stimulation promotes learning by enabling the subject to access multiple information channels. However, the extent to which multisensory information can be used as a cue to make decisions has not been fully understood. This study addressed the exploration of the parameters of multisensory stimulation delivered to behaving rats in an operant conditioning task. Preliminary data indicate that animal decisions can be shaped by online changing the stimulation parameters.

  2. Protein Multifunctionality: Principles and Mechanisms

    PubMed Central

    Zaretsky, Joseph Z.; Wreschner, Daniel H.

    2008-01-01

    In the review, the nature of protein multifunctionality is analyzed. In the first part of the review the principles of structural/functional organization of protein are discussed. In the second part, the main mechanisms involved in development of multiple functions on a single gene product(s) are analyzed. The last part represents a number of examples showing that multifunctionality is a basic feature of biologically active proteins. PMID:21566747

  3. Sounds and beyond: multisensory and other non-auditory signals in the inferior colliculus

    PubMed Central

    Gruters, Kurtis G.; Groh, Jennifer M.

    2012-01-01

    The inferior colliculus (IC) is a major processing center situated mid-way along both the ascending and descending auditory pathways of the brain stem. Although it is fundamentally an auditory area, the IC also receives anatomical input from non-auditory sources. Neurophysiological studies corroborate that non-auditory stimuli can modulate auditory processing in the IC and even elicit responses independent of coincident auditory stimulation. In this article, we review anatomical and physiological evidence for multisensory and other non-auditory processing in the IC. Specifically, the contributions of signals related to vision, eye movements and position, somatosensation, and behavioral context to neural activity in the IC will be described. These signals are potentially important for localizing sound sources, attending to salient stimuli, distinguishing environmental from self-generated sounds, and perceiving and generating communication sounds. They suggest that the IC should be thought of as a node in a highly interconnected sensory, motor, and cognitive network dedicated to synthesizing a higher-order auditory percept rather than simply reporting patterns of air pressure detected by the cochlea. We highlight some of the potential pitfalls that can arise from experimental manipulations that may disrupt the normal function of this network, such as the use of anesthesia or the severing of connections from cortical structures that project to the IC. Finally, we note that the presence of these signals in the IC has implications for our understanding not just of the IC but also of the multitude of other regions within and beyond the auditory system that are dependent on signals that pass through the IC. Whatever the IC “hears” would seem to be passed both “upward” to thalamus and thence to auditory cortex and beyond, as well as “downward” via centrifugal connections to earlier areas of the auditory pathway such as the cochlear nucleus. PMID:23248584

  4. Suppression of multisensory integration by modality-specific attention in aging

    PubMed Central

    Hugenschmidt, Christina E.; Mozolic, Jennifer L.; Laurienti, Paul J.

    2009-01-01

    Previous research demonstrates that modality-specific selective attention attenuates multisensory integration in healthy young adults. Additionally, older adults evidence enhanced multisensory integration compared to younger adults. We hypothesized that these increases were due to changes in top-down suppression, and therefore older adults would demonstrate multisensory integration while selectively attending. Performance of older and younger adults was compared on a cued discrimination task. Older adults had greater multisensory integration than younger adults in all conditions, yet were still able to reduce integration using selective attention. This suggests that attentional processes are intact in older adults, but are unable to compensate for an overall increase in the amount of sensory processing during divided attention. PMID:19218871

  5. Multisensory stimulation for people with dementia: a review of the literature.

    PubMed

    Sánchez, Alba; Millán-Calenti, José C; Lorenzo-López, Laura; Maseda, Ana

    2013-02-01

    The use of multisensory stimulation in people with dementia is becoming increasingly popular in the last decades. The aim of this review is to analyze the therapeutic effectiveness of multisensory stimulation in people with dementia. We made a search on Medline and Web of Science databases referred to all researches published from the year 1990 to 2012, which used multisensory stimulation techniques in people with dementia. The revision of the 18 articles which fulfilled the inclusion/exclusion criteria seems to prove evidence that multisensory stimulation environments produce immediate positive effects on the behavior and mood of people with dementia. Based on the above, we think it can be a useful nonpharmacological intervention on neuropsychological symptoms though, in any case, it would be necessary to start more reliable protocols from the methodological point of view in order to establish its long-term effectiveness.

  6. Multifunctional periodic cellular metals.

    PubMed

    Wadley, Haydn N G

    2006-01-15

    Periodic cellular metals with honeycomb and corrugated topologies are widely used for the cores of light weight sandwich panel structures. Honeycombs have closed cell pores and are well suited for thermal protection while also providing efficient load support. Corrugated core structures provide less efficient and highly anisotropic load support, but enable cross flow heat exchange opportunities because their pores are continuous in one direction. Recent advances in topology design and fabrication have led to the emergence of lattice truss structures with open cell structures. These three classes of periodic cellular metals can now be fabricated from a wide variety of structural alloys. Many topologies are found to provide adequate stiffness and strength for structural load support when configured as the cores of sandwich panels. Sandwich panels with core relative densities of 2-10% and cell sizes in the millimetre range are being assessed for use as multifunctional structures. The open, three-dimensional interconnected pore networks of lattice truss topologies provide opportunities for simultaneously supporting high stresses while also enabling cross flow heat exchange. These highly compressible structures also provide opportunities for the mitigation of high intensity dynamic loads created by impacts and shock waves in air or water. By filling the voids with polymers and hard ceramics, these structures have also been found to offer significant resistance to penetration by projectiles.

  7. Multifunctions of bounded variation

    NASA Astrophysics Data System (ADS)

    Vinter, R. B.

    2016-02-01

    Consider control systems described by a differential equation with a control term or, more generally, by a differential inclusion with velocity set F (t , x). Certain properties of state trajectories can be derived when it is assumed that F (t , x) is merely measurable w.r.t. the time variable t. But sometimes a refined analysis requires the imposition of stronger hypotheses regarding the time dependence. Stronger forms of necessary conditions for minimizing state trajectories can be derived, for example, when F (t , x) is Lipschitz continuous w.r.t. time. It has recently become apparent that significant addition properties of state trajectories can still be derived, when the Lipschitz continuity hypothesis is replaced by the weaker requirement that F (t , x) has bounded variation w.r.t. time. This paper introduces a new concept of multifunctions F (t , x) that have bounded variation w.r.t. time near a given state trajectory, of special relevance to control. We provide an application to sensitivity analysis.

  8. The TLC: a novel auditory nucleus of the mammalian brain.

    PubMed

    Saldaña, Enrique; Viñuela, Antonio; Marshall, Allen F; Fitzpatrick, Douglas C; Aparicio, M-Auxiliadora

    2007-11-28

    We have identified a novel nucleus of the mammalian brain and termed it the tectal longitudinal column (TLC). Basic histologic stains, tract-tracing techniques and three-dimensional reconstructions reveal that the rat TLC is a narrow, elongated structure spanning the midbrain tectum longitudinally. This paired nucleus is located close to the midline, immediately dorsal to the periaqueductal gray matter. It occupies what has traditionally been considered the most medial region of the deep superior colliculus and the most medial region of the inferior colliculus. The TLC differs from the neighboring nuclei of the superior and inferior colliculi and the periaqueductal gray by its distinct connections and cytoarchitecture. Extracellular electrophysiological recordings show that TLC neurons respond to auditory stimuli with physiologic properties that differ from those of neurons in the inferior or superior colliculi. We have identified the TLC in rodents, lagomorphs, carnivores, nonhuman primates, and humans, which indicates that the nucleus is conserved across mammals. The discovery of the TLC reveals an unexpected level of longitudinal organization in the mammalian tectum and raises questions as to the participation of this mesencephalic region in essential, yet completely unexplored, aspects of multisensory and/or sensorimotor integration.

  9. A Multisensory Cortical Network for Understanding Speech in Noise

    PubMed Central

    Bishop, Christopher W.; Miller, Lee M.

    2010-01-01

    In noisy environments, listeners tend to hear a speaker’s voice yet struggle to understand what is said. The most effective way to improve intelligibility in such conditions is to watch the speaker’s mouth movements. Here we identify the neural networks that distinguish understanding from merely hearing speech, and determine how the brain applies visual information to improve intelligibility. Using functional magnetic resonance imaging, we show that understanding speech-in-noise is supported by a network of brain areas including the left superior parietal lobule, the motor/premotor cortex, and the left anterior superior temporal sulcus (STS), a likely apex of the acoustic processing hierarchy. Multisensory integration likely improves comprehension through improved communication between the left temporal–occipital boundary, the left medial-temporal lobe, and the left STS. This demonstrates how the brain uses information from multiple modalities to improve speech comprehension in naturalistic, acoustically adverse conditions. PMID:18823249

  10. The benefit of multisensory integration with biological motion signals.

    PubMed

    Mendonça, Catarina; Santos, Jorge A; López-Moliner, Joan

    2011-09-01

    Assessing intentions, direction, and velocity of others is necessary for most daily tasks, and such information is often made available by both visual and auditory motion cues. Therefore, it is not surprising our great ability to perceive human motion. Here, we explore the multisensory integration of cues of biological motion walking speed. After testing for audiovisual asynchronies (visual signals led auditory ones by 30 ms in simultaneity temporal windows of 76.4 ms), in the main experiment, visual, auditory, and bimodal stimuli were compared to a standard audiovisual walker in a velocity discrimination task. Results in variance reduction conformed to optimal integration of congruent bimodal stimuli across all subjects. Interestingly, the perceptual judgements were still close to optimal for stimuli at the smallest level of incongruence. Comparison of slopes allows us to estimate an integration window of about 60 ms, which is smaller than that reported in audiovisual speech.

  11. Multi-sensory intervention for preterm infants improves sucking organization

    PubMed Central

    Medoff-Cooper, Barbara; Rankin, Kristin; Li, Zhuoying; Liu, Li; White-Traut, Rosemary

    2015-01-01

    Objective The aim of this RCT was to evaluate sucking organization in premature infants following a preterm infant multi-sensory intervention, the Auditory, Tactile, Visual, and Vestibular (ATVV). Study Design A convenience sample of 183 healthy premature infants born 29 - 34 weeks post-menstrual age (PMA) enrolled. Sucking organization was measured at baseline, then weekly assessments, during the infant's hospital stay. Results A quadratic trend was observed for number of sucks, sucks per burst, and maturity index, with the intervention group increasing significantly faster by day 7 (Model estimates for group*day: β = 13.69, p < 0.01; β = 1.16, p < 0.01; and β = 0.12, p < 0.05, respectively). Sucking pressure increased linearly over time, with significant between-group differences at day 14 (β = 45.66, p < 0.01). Conclusion ATVV infants exhibited improved sucking organization during hospitalization, suggestive that ATVV intervention improves oral feeding. PMID:25822519

  12. Multisensory cues capture spatial attention regardless of perceptual load.

    PubMed

    Santangelo, Valerio; Spence, Charles

    2007-12-01

    We compared the ability of auditory, visual, and audiovisual (bimodal) exogenous cues to capture visuo-spatial attention under conditions of no load versus high perceptual load. Participants had to discriminate the elevation (up vs. down) of visual targets preceded by either unimodal or bimodal cues under conditions of high perceptual load (in which they had to monitor a rapidly presented central stream of visual letters for occasionally presented target digits) or no perceptual load (in which the central stream was replaced by a fixation point). The results of 3 experiments showed that all 3 cues captured visuo-spatial attention in the no-load condition. By contrast, only the bimodal cues captured visuo-spatial attention in the high-load condition, indicating for the first time that multisensory integration can play a key role in disengaging spatial attention from a concurrent perceptually demanding stimulus.

  13. Survey on multisensory feedback virtual reality dental training systems.

    PubMed

    Wang, D; Li, T; Zhang, Y; Hou, J

    2016-11-01

    Compared with traditional dental training methods, virtual reality training systems integrated with multisensory feedback possess potentials advantages. However, there exist many technical challenges in developing a satisfactory simulator. In this manuscript, we systematically survey several current dental training systems to identify the gaps between the capabilities of these systems and the clinical training requirements. After briefly summarising the components, functions and unique features of each system, we discuss the technical challenges behind these systems including the software, hardware and user evaluation methods. Finally, the clinical requirements of an ideal dental training system are proposed. Future research/development areas are identified based on an analysis of the gaps between current systems and clinical training requirements.

  14. The multi-sensory approach as a geoeducational strategy

    NASA Astrophysics Data System (ADS)

    Musacchio, Gemma; Piangiamore, Giovanna Lucia; Pino, Nicola Alessandro

    2014-05-01

    Geoscience knowledge has a strong impact in modern society as it relates to natural hazards, sustainability and environmental issues. The general public has a demanding attitude towards the understanding of crucial geo-scientific topics that is only partly satisfied by science communication strategies and/or by outreach or school programs. A proper knowledge of the phenomena might help trigger crucial inquiries when approaching mitigation of geo-hazards and geo-resources, while providing the right tool for the understanding of news and ideas floating from the web or other media, and, in other words, help communication to be more efficient. Nonetheless available educational resources seem to be inadequate in meeting the goal, while research institutions are facing the challenge to experience new communication strategies and non-conventional way of learning capable to allow the understanding of crucial scientific contents. We suggest the use of multi-sensory approach as a successful non-conventional way of learning for children and as a different perspective of learning for older students and adults. Sense organs stimulation are perceived and processed to build the knowledge of the surrounding, including all sorts of hazards. Powerfully relying in the sense of sight, Humans have somehow lost most of their ability for a deep perception of the environment enriched by all the other senses. Since hazards involve emotions we argue that new ways to approach the learning might go exactly through emotions that one might stress with a tactile experience, a hearing or smell stimulation. To test and support our idea we are building a package of learning activities and exhibits based on a multi-sensory experience where the sight is not allowed.

  15. Coding of multisensory temporal patterns in human superior temporal sulcus

    PubMed Central

    Noesselt, Tömme; Bergmann, Daniel; Heinze, Hans-Jochen; Münte, Thomas; Spence, Charles

    2012-01-01

    Philosophers, psychologists, and neuroscientists have long been interested in how the temporal aspects of perception are represented in the brain. In the present study, we investigated the neural basis of the temporal perception of synchrony/asynchrony for audiovisual speech stimuli using functional magnetic resonance imaging (fMRI). Subjects judged the temporal relation of (a)synchronous audiovisual speech streams, and indicated any changes in their perception of the stimuli over time. Differential hemodynamic responses for synchronous versus asynchronous stimuli were observed in the multisensory superior temporal sulcus complex (mSTS-c) and prefrontal cortex. Within mSTS-c we found adjacent regions expressing an enhanced BOLD-response to the different physical (a)synchrony conditions. These regions were further modulated by the subjects' perceptual state. By calculating the distances between the modulated regions within mSTS-c in single-subjects we demonstrate that the “auditory leading (AL)” and “visual leading (VL) areas” lie closer to “synchrony areas” than to each other. Moreover, analysis of interregional connectivity indicates a stronger functional connection between multisensory prefrontal cortex and mSTS-c during the perception of asynchrony. Taken together, these results therefore suggest the presence of distinct sub-regions within the human STS-c for the maintenance of temporal relations for audiovisual speech stimuli plus differential functional connectivity with prefrontal regions. The respective local activity in mSTS-c is dependent both upon the physical properties of the stimuli presented and upon the subjects' perception of (a)synchrony. PMID:22973202

  16. Developmental changes in the multisensory temporal binding window persist into adolescence.

    PubMed

    Hillock-Dunn, Andrea; Wallace, Mark T

    2012-09-01

    We live in a world rich in sensory information, and consequently the brain is challenged with deciphering which cues from the various sensory modalities belong together. Determinations regarding the relatedness of sensory information appear to be based, at least in part, on the spatial and temporal relationships between the stimuli. Stimuli that are presented in close spatial and temporal correspondence are more likely to be associated with one another and thus 'bound' into a single perceptual entity. While there is a robust literature delineating behavioral changes in perception induced by multisensory stimuli, maturational changes in multisensory processing, particularly in the temporal realm, are poorly understood. The current study examines the developmental progression of multisensory temporal function by analyzing responses on an audiovisual simultaneity judgment task in 6- to 23-year-old participants. The overarching hypothesis for the study was that multisensory temporal function will mature with increasing age, with the developmental trajectory for this change being the primary point of inquiry. Results indeed reveal an age-dependent decrease in the size of the 'multisensory temporal binding window', the temporal interval within which multisensory stimuli are likely to be perceptually bound, with changes occurring over a surprisingly protracted time course that extends into adolescence.

  17. Evidence for enhanced multisensory facilitation with stimulus relevance: an electrophysiological investigation.

    PubMed

    Barutchu, Ayla; Freestone, Dean R; Innes-Brown, Hamish; Crewther, David P; Crewther, Sheila G

    2013-01-01

    Currently debate exists relating to the interplay between multisensory processes and bottom-up and top-down influences. However, few studies have looked at neural responses to newly paired audiovisual stimuli that differ in their prescribed relevance. For such newly associated audiovisual stimuli, optimal facilitation of motor actions was observed only when both components of the audiovisual stimuli were targets. Relevant auditory stimuli were found to significantly increase the amplitudes of the event-related potentials at the occipital pole during the first 100 ms post-stimulus onset, though this early integration was not predictive of multisensory facilitation. Activity related to multisensory behavioral facilitation was observed approximately 166 ms post-stimulus, at left central and occipital sites. Furthermore, optimal multisensory facilitation was found to be associated with a latency shift of induced oscillations in the beta range (14-30 Hz) at right hemisphere parietal scalp regions. These findings demonstrate the importance of stimulus relevance to multisensory processing by providing the first evidence that the neural processes underlying multisensory integration are modulated by the relevance of the stimuli being combined. We also provide evidence that such facilitation may be mediated by changes in neural synchronization in occipital and centro-parietal neural populations at early and late stages of neural processing that coincided with stimulus selection, and the preparation and initiation of motor action.

  18. Taking a call is facilitated by the multisensory processing of smartphone vibrations, sounds, and flashes.

    PubMed

    Pomper, Ulrich; Brincker, Jana; Harwood, James; Prikhodko, Ivan; Senkowski, Daniel

    2014-01-01

    Many electronic devices that we use in our daily lives provide inputs that need to be processed and integrated by our senses. For instance, ringing, vibrating, and flashing indicate incoming calls and messages in smartphones. Whether the presentation of multiple smartphone stimuli simultaneously provides an advantage over the processing of the same stimuli presented in isolation has not yet been investigated. In this behavioral study we examined multisensory processing between visual (V), tactile (T), and auditory (A) stimuli produced by a smartphone. Unisensory V, T, and A stimuli as well as VA, AT, VT, and trisensory VAT stimuli were presented in random order. Participants responded to any stimulus appearance by touching the smartphone screen using the stimulated hand (Experiment 1), or the non-stimulated hand (Experiment 2). We examined violations of the race model to test whether shorter response times to multisensory stimuli exceed probability summations of unisensory stimuli. Significant violations of the race model, indicative of multisensory processing, were found for VA stimuli in both experiments and for VT stimuli in Experiment 1. Across participants, the strength of this effect was not associated with prior learning experience and daily use of smartphones. This indicates that this integration effect, similar to what has been previously reported for the integration of semantically meaningless stimuli, could involve bottom-up driven multisensory processes. Our study demonstrates for the first time that multisensory processing of smartphone stimuli facilitates taking a call. Thus, research on multisensory integration should be taken into consideration when designing electronic devices such as smartphones.

  19. Enhanced multifunctional paint for detection of radiation

    DOEpatents

    Farmer, Joseph C.; Moses, Edward Ira; Rubenchik, Alexander M.

    2017-03-07

    An enhanced multifunctional paint apparatus, systems, and methods for detecting radiation on a surface include providing scintillation particles; providing an enhance neutron absorptive material; providing a binder; combining the scintillation particles, the enhance neutron absorptive material, and the binder creating a multifunctional paint; applying the multifunctional paint to the surface; and monitoring the surface for detecting radiation.

  20. Terahertz Nanoscience of Multifunctional Materials: Atomistic Exploration

    DTIC Science & Technology

    2014-03-28

    Approved for Public Release; Distribution Unlimited Final report on the project "Terahertz Nanoscience of Multifunctional Materials: Atomistic...non peer-reviewed journals: Final report on the project "Terahertz Nanoscience of Multifunctional Materials: Atomistic Exploration" Report Title In... nanoscience of multifunctional materials: atomistic exploration” PI:Inna Ponomareva We have accomplished the following. 1. We have developed a set of

  1. Multifunctional pattern-generating circuits.

    PubMed

    Briggman, K L; Kristan, W B

    2008-01-01

    The ability of distinct anatomical circuits to generate multiple behavioral patterns is widespread among vertebrate and invertebrate species. These multifunctional neuronal circuits are the result of multistable neural dynamics and modular organization. The evidence suggests multifunctional circuits can be classified by distinct architectures, yet the activity patterns of individual neurons involved in more than one behavior can vary dramatically. Several mechanisms, including sensory input, the parallel activity of projection neurons, neuromodulation, and biomechanics, are responsible for the switching between patterns. Recent advances in both analytical and experimental tools have aided the study of these complex circuits.

  2. Glyconanoparticles: multifunctional nanomaterials for biomedical applications.

    PubMed

    García, Isabel; Marradi, Marco; Penadés, Soledad

    2010-07-01

    Metal-based glyconanoparticles (GNPs) are biofunctional nanomaterials that combine the unique physical, chemical and optical properties of the metallic nucleus with the characteristics of the carbohydrate coating. The latter characteristics comprise a series of advantages that range from ensuring water solubility, biocompatibility and stability to targeting properties. The selection of suitable carbohydrates for specifically targeting biomarkers opens up the possibility to employ metallic GNPs in diagnostics and/or therapy. Within the vast nanoscience field, this review intends to focus on the advances of multifunctional and multimodal GNPs, which make use of the 'glycocode' to specifically address pathogens or pathological-related biomedical problems. Examples of their potential application in antiadhesion therapy and diagnosis are highlighted. From the ex vivo diagnostic perspective, it can be predicted that GNPs will soon be used clinically. However, the in vivo application of metallic GNPs in humans will probably need more time. In particular, major concerns regarding nanotoxicity need to be exhaustively addressed. However, it is expected that the sugar shell of GNPs will lower the intrinsic toxicity of metal nanoclusters better than other non-natural coatings.

  3. Changes in effective connectivity of human superior parietal lobule under multisensory and unisensory stimulation.

    PubMed

    Moran, R J; Molholm, S; Reilly, R B; Foxe, J J

    2008-05-01

    Previous event-related potential (ERP) studies have identified the superior parietal lobule (SPL) as actively multisensory. This study compares effective, or contextually active, connections to this region under unisensory and multisensory conditions. Effective connectivity, the influence of one brain region over another, during unisensory visual, unisensory auditory and multisensory audiovisual stimulation was investigated. ERPs were recorded from subdural electrodes placed over the parietal lobe of three patients while they conducted a rapid reaction-time task. A generative model of interacting neuronal ensembles for ERPs was inverted in a scheme allowing investigation of the connections from and to the SPL, a multisensory processing area. Important features of the ensemble model include inhibitory and excitatory feedback connections to pyramidal cells and extrinsic input to the stellate cell pool, with extrinsic forward and backward connections delineated by laminar connection differences between ensembles. The framework embeds the SPL in a plausible connection of distinct neuronal ensembles mirroring the integrated brain regions involved in the response task. Bayesian model comparison was used to test competing feed-forward and feed-backward models of how the electrophysiological data were generated. Comparisons were performed between multisensory and unisensory data. Findings from three patients show differences in summed unisensory and multisensory ERPs that can be accounted for by a mediation of both forward and backward connections to the SPL. In particular, a negative gain in all forward and backward connections to the SPL from other regions was observed during the period of multisensory integration, while a positive gain was observed for forward projections that arise from the SPL.

  4. Role of the anterior insular cortex in integrative causal signaling during multisensory auditory-visual attention.

    PubMed

    Chen, Tianwen; Michels, Lars; Supekar, Kaustubh; Kochalka, John; Ryali, Srikanth; Menon, Vinod

    2015-01-01

    Coordinated attention to information from multiple senses is fundamental to our ability to respond to salient environmental events, yet little is known about brain network mechanisms that guide integration of information from multiple senses. Here we investigate dynamic causal mechanisms underlying multisensory auditory-visual attention, focusing on a network of right-hemisphere frontal-cingulate-parietal regions implicated in a wide range of tasks involving attention and cognitive control. Participants performed three 'oddball' attention tasks involving auditory, visual and multisensory auditory-visual stimuli during fMRI scanning. We found that the right anterior insula (rAI) demonstrated the most significant causal influences on all other frontal-cingulate-parietal regions, serving as a major causal control hub during multisensory attention. Crucially, we then tested two competing models of the role of the rAI in multisensory attention: an 'integrated' signaling model in which the rAI generates a common multisensory control signal associated with simultaneous attention to auditory and visual oddball stimuli versus a 'segregated' signaling model in which the rAI generates two segregated and independent signals in each sensory modality. We found strong support for the integrated, rather than the segregated, signaling model. Furthermore, the strength of the integrated control signal from the rAI was most pronounced on the dorsal anterior cingulate and posterior parietal cortices, two key nodes of saliency and central executive networks respectively. These results were preserved with the addition of a superior temporal sulcus region involved in multisensory processing. Our study provides new insights into the dynamic causal mechanisms by which the AI facilitates multisensory attention.

  5. Experience with adults shapes multisensory representation of social familiarity in the brain of a songbird.

    PubMed

    George, Isabelle; Cousillas, Hugo; Richard, Jean-Pierre; Hausberger, Martine

    2012-01-01

    Social animals learn to perceive their social environment, and their social skills and preferences are thought to emerge from greater exposure to and hence familiarity with some social signals rather than others. Familiarity appears to be tightly linked to multisensory integration. The ability to differentiate and categorize familiar and unfamiliar individuals and to build a multisensory representation of known individuals emerges from successive social interactions, in particular with adult, experienced models. In different species, adults have been shown to shape the social behavior of young by promoting selective attention to multisensory cues. The question of what representation of known conspecifics adult-deprived animals may build therefore arises. Here we show that starlings raised with no experience with adults fail to develop a multisensory representation of familiar and unfamiliar starlings. Electrophysiological recordings of neuronal activity throughout the primary auditory area of these birds, while they were exposed to audio-only or audiovisual familiar and unfamiliar cues, showed that visual stimuli did, as in wild-caught starlings, modulate auditory responses but that, unlike what was observed in wild-caught birds, this modulation was not influenced by familiarity. Thus, adult-deprived starlings seem to fail to discriminate between familiar and unfamiliar individuals. This suggests that adults may shape multisensory representation of known individuals in the brain, possibly by focusing the young's attention on relevant, multisensory cues. Multisensory stimulation by experienced, adult models may thus be ubiquitously important for the development of social skills (and of the neural properties underlying such skills) in a variety of species.

  6. The Nucleus Introduced

    PubMed Central

    Pederson, Thoru

    2011-01-01

    Now is an opportune moment to address the confluence of cell biological form and function that is the nucleus. Its arrival is especially timely because the recognition that the nucleus is extremely dynamic has now been solidly established as a paradigm shift over the past two decades, and also because we now see on the horizon numerous ways in which organization itself, including gene location and possibly self-organizing bodies, underlies nuclear functions. PMID:20660024

  7. Multi-functional composite structures

    SciTech Connect

    Mulligan, Anthony C.; Halloran, John; Popovich, Dragan; Rigali, Mark J.; Sutaria, Manish P.; Vaidyanathan, K. Ranji; Fulcher, Michael L.; Knittel, Kenneth L.

    2004-10-19

    Fibrous monolith processing techniques to fabricate multifunctional structures capable of performing more than one discrete function such as structures capable of bearing structural loads and mechanical stresses in service and also capable of performing at least one additional non-structural function.

  8. Multi-functional composite structures

    DOEpatents

    Mulligan, Anthony C.; Halloran, John; Popovich, Dragan; Rigali, Mark J.; Sutaria, Manish P.; Vaidyanathan, K. Ranji; Fulcher, Michael L.; Knittel, Kenneth L.

    2010-04-27

    Fibrous monolith processing techniques to fabricate multifunctional structures capable of performing more than one discrete function such as structures capable of bearing structural loads and mechanical stresses in service and also capable of performing at least one additional non-structural function.

  9. The roles of physical and physiological simultaneity in audiovisual multisensory facilitation

    PubMed Central

    Leone, Lynnette M.; McCourt, Mark E.

    2013-01-01

    A series of experiments measured the audiovisual stimulus onset asynchrony (SOAAV), yielding facilitative multisensory integration. We evaluated (1) the range of SOAAV over which facilitation occurred when unisensory stimuli were weak; (2) whether the range of SOAAV producing facilitation supported the hypothesis that physiological simultaneity of unisensory activity governs multisensory facilitation; and (3) whether AV multisensory facilitation depended on relative stimulus intensity. We compared response-time distributions to unisensory auditory (A) and visual (V) stimuli with those to AV stimuli over a wide range (300 and 20 ms increments) of SOAAV, across four conditions of varying stimulus intensity. In condition 1, the intensity of unisensory stimuli was adjusted such that d′ ≈ 2. In condition 2, V stimulus intensity was increased (d′ > 4), while A stimulus intensity was as in condition 1. In condition 3, A stimulus intensity was increased (d′ > 4) while V stimulus intensity was as in condition 1. In condition 4, both A and V stimulus intensities were increased to clearly suprathreshold levels (d′ > 4). Across all conditions of stimulus intensity, significant multisensory facilitation occurred exclusively for simultaneously presented A and V stimuli. In addition, facilitation increased as stimulus intensity increased, in disagreement with inverse effectiveness. These results indicate that the requirements for facilitative multisensory integration include both physical and physiological simultaneity. PMID:24349682

  10. The roles of physical and physiological simultaneity in audiovisual multisensory facilitation.

    PubMed

    Leone, Lynnette M; McCourt, Mark E

    2013-01-01

    A series of experiments measured the audiovisual stimulus onset asynchrony (SOAAV), yielding facilitative multisensory integration. We evaluated (1) the range of SOAAV over which facilitation occurred when unisensory stimuli were weak; (2) whether the range of SOAAV producing facilitation supported the hypothesis that physiological simultaneity of unisensory activity governs multisensory facilitation; and (3) whether AV multisensory facilitation depended on relative stimulus intensity. We compared response-time distributions to unisensory auditory (A) and visual (V) stimuli with those to AV stimuli over a wide range (300 and 20 ms increments) of SOAAV, across four conditions of varying stimulus intensity. In condition 1, the intensity of unisensory stimuli was adjusted such that d' ≈ 2. In condition 2, V stimulus intensity was increased (d' > 4), while A stimulus intensity was as in condition 1. In condition 3, A stimulus intensity was increased (d' > 4) while V stimulus intensity was as in condition 1. In condition 4, both A and V stimulus intensities were increased to clearly suprathreshold levels (d' > 4). Across all conditions of stimulus intensity, significant multisensory facilitation occurred exclusively for simultaneously presented A and V stimuli. In addition, facilitation increased as stimulus intensity increased, in disagreement with inverse effectiveness. These results indicate that the requirements for facilitative multisensory integration include both physical and physiological simultaneity.

  11. Facilitation of multisensory integration by the "unity effect" reveals that speech is special.

    PubMed

    Vatakis, Argiro; Ghazanfar, Asif A; Spence, Charles

    2008-07-29

    Whenever two or more sensory inputs are highly consistent in one or more dimension(s), observers will be more likely to perceive them as a single multisensory event rather than as separate unimodal events. For audiovisual speech, but not for other noncommunicative events, participants exhibit a "unity effect," whereby they are less sensitive to temporal asynchrony (i.e., that are more likely to bind the multisensory signals together) for matched (than for mismatched) speech events. This finding suggests that the modulation of multisensory integration by the unity effect in humans may be specific to speech. To test this hypothesis directly, we investigated whether the unity effect would also influence the multisensory integration of vocalizations from another primate species, the rhesus monkey. Human participants made temporal order judgments for both matched and mismatched audiovisual stimuli presented at a range of stimulus-onset asynchronies. The unity effect was examined with (1) a single call-type across two different monkeys, (2) two different call-types from the same monkey, (3) human versus monkey "cooing," and (4) speech sounds produced by a male and a female human. The results show that the unity effect only influenced participants' performance for the speech stimuli; no effect was observed for monkey vocalizations or for the human imitations of monkey calls. These findings suggest that the facilitation of multisensory integration by the unity effect is specific to human speech signals.

  12. The Construct of the Multisensory Temporal Binding Window and its Dysregulation in Developmental Disabilities

    PubMed Central

    Wallace, Mark T.; Stevenson, Ryan A.

    2014-01-01

    Behavior, perception and cognition are strongly shaped by the synthesis of information across the different sensory modalities. Such multisensory integration often results in performance and perceptual benefits that reflect the additional information conferred by having cues from multiple senses providing redundant or complementary information. The spatial and temporal relationships of these cues provide powerful statistical information about how these cues should be integrated or “bound” in order to create a unified perceptual representation. Much recent work has examined the temporal factors that are integral in multisensory processing, with many focused on the construct of the multisensory temporal binding window – the epoch of time within which stimuli from different modalities is likely to be integrated and perceptually bound. Emerging evidence suggests that this temporal window is altered in a series of neurodevelopmental disorders, including autism, dyslexia and schizophrenia. In addition to their role in sensory processing, these deficits in multisensory temporal function may play an important role in the perceptual and cognitive weaknesses that characterize these clinical disorders. Within this context, focus on improving the acuity of multisensory temporal function may have important implications for the amelioration of the “higher-order” deficits that serve as the defining features of these disorders. PMID:25128432

  13. Augmented multisensory feedback enhances locomotor adaptation in humans with incomplete spinal cord injury.

    PubMed

    Yen, Sheng-Che; Landry, Jill M; Wu, Ming

    2014-06-01

    Different forms of augmented feedback may engage different motor learning pathways, but it is unclear how these pathways interact with each other, especially in patients with incomplete spinal cord injury (SCI). The purpose of this study was to test whether augmented multisensory feedback could enhance aftereffects following short term locomotor training (i.e., adaptation) in patients with incomplete SCI. A total of 10 subjects with incomplete SCI were recruited to perform locomotor adaptation. Three types of augmented feedback were provided during the adaptation: (a) computerized visual cues showing the actual and target stride length (augmented visual feedback); (b) a swing resistance applied to the leg (augmented proprioceptive feedback); (c) a combination of the visual cues and resistance (augmented multisensory feedback). The results showed that subjects' stride length increased in all conditions following the adaptation, but the increase was greater and retained longer in the multisensory feedback condition. The multisensory feedback provided in this study may engage both explicit and implicit learning pathways during the adaptation and in turn enhance the aftereffect. The results implied that multisensory feedback may be used as an adjunctive approach to enhance gait recovery in humans with SCI.

  14. Dynamic weighting of multisensory stimuli shapes decision-making in rats and humans

    PubMed Central

    Sheppard, John P.; Raposo, David; Churchland, Anne K.

    2013-01-01

    Stimuli that animals encounter in the natural world are frequently time-varying and activate multiple sensory systems together. Such stimuli pose a major challenge for the brain: Successful multisensory integration requires subjects to estimate the reliability of each modality and use these estimates to weight each signal appropriately. Here, we examined whether humans and rats can estimate the reliability of time-varying multisensory stimuli when stimulus reliability changes unpredictably from trial to trial. Using an existing multisensory decision task that features time-varying audiovisual stimuli, we independently manipulated the signal-to-noise ratios of each modality and measured subjects' decisions on single- and multi-sensory trials. We report three main findings: (a) Sensory reliability influences how subjects weight multisensory evidence even for time-varying, stochastic stimuli. (b) The ability to exploit sensory reliability extends beyond human and nonhuman primates: Rodents and humans both weight incoming sensory information in a reliability-dependent manner. (c) Regardless of sensory reliability, most subjects are disinclined to make “snap judgments” and instead base decisions on evidence presented over the majority of the trial duration. Rare departures from this trend highlight the importance of using time-varying stimuli that permit this analysis. Taken together, these results suggest that the brain's ability to use stimulus reliability to guide decision-making likely relies on computations that are conserved across species and operate over a wide range of stimulus conditions. PMID:23658374

  15. Dynamic weighting of multisensory stimuli shapes decision-making in rats and humans.

    PubMed

    Sheppard, John P; Raposo, David; Churchland, Anne K

    2013-05-08

    Stimuli that animals encounter in the natural world are frequently time-varying and activate multiple sensory systems together. Such stimuli pose a major challenge for the brain: Successful multisensory integration requires subjects to estimate the reliability of each modality and use these estimates to weight each signal appropriately. Here, we examined whether humans and rats can estimate the reliability of time-varying multisensory stimuli when stimulus reliability changes unpredictably from trial to trial. Using an existing multisensory decision task that features time-varying audiovisual stimuli, we independently manipulated the signal-to-noise ratios of each modality and measured subjects' decisions on single- and multi-sensory trials. We report three main findings: (a) Sensory reliability influences how subjects weight multisensory evidence even for time-varying, stochastic stimuli. (b) The ability to exploit sensory reliability extends beyond human and nonhuman primates: Rodents and humans both weight incoming sensory information in a reliability-dependent manner. (c) Regardless of sensory reliability, most subjects are disinclined to make "snap judgments" and instead base decisions on evidence presented over the majority of the trial duration. Rare departures from this trend highlight the importance of using time-varying stimuli that permit this analysis. Taken together, these results suggest that the brain's ability to use stimulus reliability to guide decision-making likely relies on computations that are conserved across species and operate over a wide range of stimulus conditions.

  16. Comparative Effects of Multisensory and Metacognitive Instructional Approaches on English Vocabulary Achievement of Underachieving Nigerian Secondary School Students

    ERIC Educational Resources Information Center

    Adeniyi, Folakemi O.; Lawal, R. Adebayo

    2012-01-01

    The purpose of this study was to find out the relative effects of three instructional Approaches i.e. Multisensory, Metacognitive, and a combination of Multisensory and Metacognitive Instructional Approaches on the Vocabulary achievement of underachieving Secondary School Students. The study adopted the quasi-experimental design in which a…

  17. Primary and multisensory cortical activity is correlated with audiovisual percepts.

    PubMed

    Benoit, Margo McKenna; Raij, Tommi; Lin, Fa-Hsuan; Jääskeläinen, Iiro P; Stufflebeam, Steven

    2010-04-01

    Incongruent auditory and visual stimuli can elicit audiovisual illusions such as the McGurk effect where visual /ka/ and auditory /pa/ fuse into another percept such as/ta/. In the present study, human brain activity was measured with adaptation functional magnetic resonance imaging to investigate which brain areas support such audiovisual illusions. Subjects viewed trains of four movies beginning with three congruent /pa/ stimuli to induce adaptation. The fourth stimulus could be (i) another congruent /pa/, (ii) a congruent /ka/, (iii) an incongruent stimulus that evokes the McGurk effect in susceptible individuals (lips /ka/ voice /pa/), or (iv) the converse combination that does not cause the McGurk effect (lips /pa/ voice/ ka/). This paradigm was predicted to show increased release from adaptation (i.e. stronger brain activation) when the fourth movie and the related percept was increasingly different from the three previous movies. A stimulus change in either the auditory or the visual stimulus from /pa/ to /ka/ (iii, iv) produced within-modality and cross-modal responses in primary auditory and visual areas. A greater release from adaptation was observed for incongruent non-McGurk (iv) compared to incongruent McGurk (iii) trials. A network including the primary auditory and visual cortices, nonprimary auditory cortex, and several multisensory areas (superior temporal sulcus, intraparietal sulcus, insula, and pre-central cortex) showed a correlation between perceiving the McGurk effect and the fMRI signal, suggesting that these areas support the audiovisual illusion.

  18. Learning to integrate contradictory multisensory self-motion cue pairings.

    PubMed

    Kaliuzhna, Mariia; Prsa, Mario; Gale, Steven; Lee, Stella J; Blanke, Olaf

    2015-01-14

    Humans integrate multisensory information to reduce perceptual uncertainty when perceiving the world and self. Integration fails, however, if a common causality is not attributed to the sensory signals, as would occur in conditions of spatiotemporal discrepancies. In the case of passive self-motion, visual and vestibular cues are integrated according to statistical optimality, yet the extent of cue conflicts that do not compromise this optimality is currently underexplored. Here, we investigate whether human subjects can learn to integrate two arbitrary, but co-occurring, visual and vestibular cues of self-motion. Participants made size comparisons between two successive whole-body rotations using only visual, only vestibular, and both modalities together. The vestibular stimulus provided a yaw self-rotation cue, the visual a roll (Experiment 1) or pitch (Experiment 2) rotation cue. Experimentally measured thresholds in the bimodal condition were compared with theoretical predictions derived from the single-cue thresholds. Our results show that human subjects combine and optimally integrate vestibular and visual information, each signaling self-motion around a different rotation axis (yaw vs. roll and yaw vs. pitch). This finding suggests that the experience of two temporally co-occurring but spatially unrelated self-motion cues leads to inferring a common cause for these two initially unrelated sources of information about self-motion. We discuss our results in terms of specific task demands, cross-modal adaptation, and spatial compatibility. The importance of these results for the understanding of bodily illusions is also discussed.

  19. Multisensory interactions between auditory and haptic object recognition.

    PubMed

    Kassuba, Tanja; Menz, Mareike M; Röder, Brigitte; Siebner, Hartwig R

    2013-05-01

    Object manipulation produces characteristic sounds and causes specific haptic sensations that facilitate the recognition of the manipulated object. To identify the neural correlates of audio-haptic binding of object features, healthy volunteers underwent functional magnetic resonance imaging while they matched a target object to a sample object within and across audition and touch. By introducing a delay between the presentation of sample and target stimuli, it was possible to dissociate haptic-to-auditory and auditory-to-haptic matching. We hypothesized that only semantically coherent auditory and haptic object features activate cortical regions that host unified conceptual object representations. The left fusiform gyrus (FG) and posterior superior temporal sulcus (pSTS) showed increased activation during crossmodal matching of semantically congruent but not incongruent object stimuli. In the FG, this effect was found for haptic-to-auditory and auditory-to-haptic matching, whereas the pSTS only displayed a crossmodal matching effect for congruent auditory targets. Auditory and somatosensory association cortices showed increased activity during crossmodal object matching which was, however, independent of semantic congruency. Together, the results show multisensory interactions at different hierarchical stages of auditory and haptic object processing. Object-specific crossmodal interactions culminate in the left FG, which may provide a higher order convergence zone for conceptual object knowledge.

  20. Assessing the benefits of multisensory audiotactile stimulation for overweight individuals.

    PubMed

    Wan, Xiaoang; Spence, Charles; Mu, Bingbing; Zhou, Xi; Ho, Cristy

    2014-04-01

    We report an experiment designed to examine whether individuals who are overweight would perform differently when trying to detect and/or discriminate auditory, vibrotactile, and audiotactile targets. The vibrotactile stimuli were delivered either to the participant's abdomen or to his hand. Thirty-six young male participants were classified into normal, underweight, or overweight groups based on their body mass index. All three groups exhibited a significant benefit of multisensory (over the best of the unisensory) stimulation, but the magnitude of this benefit was modulated by the weight of the participant, the task, and the location from which the vibrotactile stimuli happened to be presented. For the detection task, the overweight group exhibited a significantly smaller benefit than the underweight group. In the discrimination task, the overweight group showed significantly more benefits than the other two groups when the vibrotactile stimuli were delivered to their hands, but not when the stimuli were delivered to their abdomens. These results might raise some interesting questions regarding the mechanisms underlying audiotactile information processing and have applied relevance for the design of the most effective warning signal (e.g., for drivers).

  1. Bimodal and trimodal multisensory enhancement: effects of stimulus onset and intensity on reaction time.

    PubMed

    Diederich, Adele; Colonius, Hans

    2004-11-01

    Manual reaction times to visual, auditory, and tactile stimuli presented simultaneously, or with a delay, were measured to test for multisensory interaction effects in a simple detection task with redundant signals. Responses to trimodal stimulus combinations were faster than those to bimodal combinations, which in turn were faster than reactions to unimodal stimuli. Response enhancement increased with decreasing auditory and tactile stimulus intensity and was a U-shaped function of stimulus onset asynchrony. Distribution inequality tests indicated that the multisensory interaction effects were larger than predicted by separate activation models, including the difference between bimodal and trimodal response facilitation. The results are discussed with respect to previous findings in a focused attention task and are compared with multisensory integration rules observed in bimodal and trimodal superior colliculus neurons in the cat and monkey.

  2. Auditory-driven phase reset in visual cortex: Human electrocorticography reveals mechanisms of early multisensory integration

    PubMed Central

    Mercier, Manuel R.; Foxe, John J.; Fiebelkorn, Ian C.; Butler, John S.; Schwartz, Theodore H.; Molholm, Sophie

    2013-01-01

    Findings in animal models demonstrate that activity within hierarchically early sensory cortical regions can be modulated by cross-sensory inputs through resetting of the phase of ongoing intrinsic neural oscillations. Here, subdural recordings evaluated whether phase resetting by auditory inputs would impact multisensory integration processes in human visual cortex. Results clearly showed auditory-driven phase reset in visual cortices and, in some cases, frank auditory event-related potentials (ERP) were also observed over these regions. Further, when audiovisual bisensory stimuli were presented, this led to robust multisensory integration effects which were observed in both the ERP and in measures of phase concentration. These results extend findings from animal models to human visual cortices, and highlight the impact of cross-sensory phase resetting by a non-primary stimulus on multisensory integration in ostensibly unisensory cortices. PMID:23624493

  3. Effect of mechanical tactile noise on amplitude of visual evoked potentials: multisensory stochastic resonance

    PubMed Central

    Huidobro, Nayeli; Silva, Mayte; Flores, Amira; Trenado, Carlos; Quintanar, Luis; Arias-Carrión, Oscar; Kristeva, Rumyana

    2015-01-01

    The present investigation documents the electrophysiological occurrence of multisensory stochastic resonance in the human visual pathway elicited by tactile noise. We define multisensory stochastic resonance of brain evoked potentials as the phenomenon in which an intermediate level of input noise of one sensory modality enhances the brain evoked response of another sensory modality. Here we examined this phenomenon in visual evoked potentials (VEPs) modulated by the addition of tactile noise. Specifically, we examined whether a particular level of mechanical Gaussian noise applied to the index finger can improve the amplitude of the VEP. We compared the amplitude of the positive P100 VEP component between zero noise (ZN), optimal noise (ON), and high mechanical noise (HN). The data disclosed an inverted U-like graph for all the subjects, thus demonstrating the occurrence of a multisensory stochastic resonance in the P100 VEP. PMID:26156387

  4. Effect of mechanical tactile noise on amplitude of visual evoked potentials: multisensory stochastic resonance.

    PubMed

    Méndez-Balbuena, Ignacio; Huidobro, Nayeli; Silva, Mayte; Flores, Amira; Trenado, Carlos; Quintanar, Luis; Arias-Carrión, Oscar; Kristeva, Rumyana; Manjarrez, Elias

    2015-10-01

    The present investigation documents the electrophysiological occurrence of multisensory stochastic resonance in the human visual pathway elicited by tactile noise. We define multisensory stochastic resonance of brain evoked potentials as the phenomenon in which an intermediate level of input noise of one sensory modality enhances the brain evoked response of another sensory modality. Here we examined this phenomenon in visual evoked potentials (VEPs) modulated by the addition of tactile noise. Specifically, we examined whether a particular level of mechanical Gaussian noise applied to the index finger can improve the amplitude of the VEP. We compared the amplitude of the positive P100 VEP component between zero noise (ZN), optimal noise (ON), and high mechanical noise (HN). The data disclosed an inverted U-like graph for all the subjects, thus demonstrating the occurrence of a multisensory stochastic resonance in the P100 VEP.

  5. Multifunctional nanoparticles for cancer immunotherapy

    PubMed Central

    Saleh, Tayebeh; Shojaosadati, Seyed Abbas

    2016-01-01

    ABSTRACT During the last decades significant progress has been made in the field of cancer immunotherapy. However, cancer vaccines have not been successful in clinical trials due to poor immunogenicity of antigen, limitations of safety associated with traditional systemic delivery as well as the complex regulation of the immune system in tumor microenvironment. In recent years, nanotechnology-based delivery systems have attracted great interest in the field of immunotherapy since they provide new opportunities to fight the cancer. In particular, for delivery of cancer vaccines, multifunctional nanoparticles present many advantages such as targeted delivery to immune cells, co-delivery of therapeutic agents, reduced adverse outcomes, blocked immune checkpoint molecules, and amplify immune activation via the use of stimuli-responsive or immunostimulatory materials. In this review article, we highlight recent progress and future promise of multifunctional nanoparticles that have been applied to enhance the efficiency of cancer vaccines. PMID:26901287

  6. Individual Differences in the Multisensory Temporal Binding Window Predict Susceptibility to Audiovisual Illusions

    PubMed Central

    Stevenson, Ryan A.; Zemtsov, Raquel K.; Wallace, Mark T.

    2013-01-01

    Human multisensory systems are known to bind inputs from the different sensory modalities into a unified percept, a process that leads to measurable behavioral benefits. This integrative process can be observed through multisensory illusions, including the McGurk effect and the sound-induced flash illusion, both of which demonstrate the ability of one sensory modality to modulate perception in a second modality. Such multisensory integration is highly dependent upon the temporal relationship of the different sensory inputs, with perceptual binding occurring within a limited range of asynchronies known as the temporal binding window (TBW). Previous studies have shown that this window is highly variable across individuals, but it is unclear how these variations in the TBW relate to an individual’s ability to integrate multisensory cues. Here we provide evidence linking individual differences in multisensory temporal processes to differences in the individual’s audiovisual integration of illusory stimuli. Our data provide strong evidence that the temporal processing of multiple sensory signals and the merging of multiple signals into a single, unified perception, are highly related. Specifically, the width of right side of an individuals’ TBW, where the auditory stimulus follows the visual, is significantly correlated with the strength of illusory percepts, as indexed via both an increase in the strength of binding synchronous sensory signals and in an improvement in correctly dissociating asynchronous signals. These findings are discussed in terms of their possible neurobiological basis, relevance to the development of sensory integration, and possible importance for clinical conditions in which there is growing evidence that multisensory integration is compromised. PMID:22390292

  7. Electrical neuroimaging of memory discrimination based on single-trial multisensory learning.

    PubMed

    Thelen, Antonia; Cappe, Céline; Murray, Micah M

    2012-09-01

    Multisensory experiences influence subsequent memory performance and brain responses. Studies have thus far concentrated on semantically congruent pairings, leaving unresolved the influence of stimulus pairing and memory sub-types. Here, we paired images with unique, meaningless sounds during a continuous recognition task to determine if purely episodic, single-trial multisensory experiences can incidentally impact subsequent visual object discrimination. Psychophysics and electrical neuroimaging analyses of visual evoked potentials (VEPs) compared responses to repeated images either paired or not with a meaningless sound during initial encounters. Recognition accuracy was significantly impaired for images initially presented as multisensory pairs and could not be explained in terms of differential attention or transfer of effects from encoding to retrieval. VEP modulations occurred at 100-130 ms and 270-310 ms and stemmed from topographic differences indicative of network configuration changes within the brain. Distributed source estimations localized the earlier effect to regions of the right posterior temporal gyrus (STG) and the later effect to regions of the middle temporal gyrus (MTG). Responses in these regions were stronger for images previously encountered as multisensory pairs. Only the later effect correlated with performance such that greater MTG activity in response to repeated visual stimuli was linked with greater performance decrements. The present findings suggest that brain networks involved in this discrimination may critically depend on whether multisensory events facilitate or impair later visual memory performance. More generally, the data support models whereby effects of multisensory interactions persist to incidentally affect subsequent behavior as well as visual processing during its initial stages.

  8. Individual differences in the multisensory temporal binding window predict susceptibility to audiovisual illusions.

    PubMed

    Stevenson, Ryan A; Zemtsov, Raquel K; Wallace, Mark T

    2012-12-01

    Human multisensory systems are known to bind inputs from the different sensory modalities into a unified percept, a process that leads to measurable behavioral benefits. This integrative process can be observed through multisensory illusions, including the McGurk effect and the sound-induced flash illusion, both of which demonstrate the ability of one sensory modality to modulate perception in a second modality. Such multisensory integration is highly dependent upon the temporal relationship of the different sensory inputs, with perceptual binding occurring within a limited range of asynchronies known as the temporal binding window (TBW). Previous studies have shown that this window is highly variable across individuals, but it is unclear how these variations in the TBW relate to an individual's ability to integrate multisensory cues. Here we provide evidence linking individual differences in multisensory temporal processes to differences in the individual's audiovisual integration of illusory stimuli. Our data provide strong evidence that the temporal processing of multiple sensory signals and the merging of multiple signals into a single, unified perception, are highly related. Specifically, the width of right side of an individuals' TBW, where the auditory stimulus follows the visual, is significantly correlated with the strength of illusory percepts, as indexed via both an increase in the strength of binding synchronous sensory signals and in an improvement in correctly dissociating asynchronous signals. These findings are discussed in terms of their possible neurobiological basis, relevance to the development of sensory integration, and possible importance for clinical conditions in which there is growing evidence that multisensory integration is compromised.

  9. Kaon-nucleus scattering

    NASA Technical Reports Server (NTRS)

    Hong, Byungsik; Maung, Khin Maung; Wilson, John W.; Buck, Warren W.

    1989-01-01

    The derivations of the Lippmann-Schwinger equation and Watson multiple scattering are given. A simple optical potential is found to be the first term of that series. The number density distribution models of the nucleus, harmonic well, and Woods-Saxon are used without t-matrix taken from the scattering experiments. The parameterized two-body inputs, which are kaon-nucleon total cross sections, elastic slope parameters, and the ratio of the real to the imaginary part of the forward elastic scattering amplitude, are presented. The eikonal approximation was chosen as our solution method to estimate the total and absorptive cross sections for the kaon-nucleus scattering.

  10. Kaon-nucleus scattering

    NASA Technical Reports Server (NTRS)

    Hong, Byungsik; Buck, Warren W.; Maung, Khin M.

    1989-01-01

    Two kinds of number density distributions of the nucleus, harmonic well and Woods-Saxon models, are used with the t-matrix that is taken from the scattering experiments to find a simple optical potential. The parameterized two body inputs, which are kaon-nucleon total cross sections, elastic slope parameters, and the ratio of the real to imaginary part of the forward elastic scattering amplitude, are shown. The eikonal approximation was chosen as the solution method to estimate the total and absorptive cross sections for the kaon-nucleus scattering.

  11. Multifunctional Information Distribution System (MIDS)

    DTIC Science & Technology

    2015-12-01

    Selected Acquisition Report (SAR) RCS: DD-A&T(Q&A)823-554 Multifunctional Information Distribution System (MIDS) As of FY 2017 President’s Budget...Program Office Estimate RDT&E - Research, Development, Test, and Evaluation SAR - Selected Acquisition Report SCP - Service Cost Position TBD - To Be... selectable levels Multiple selectable levels >=200 with IF for 1000 200 with IF Multiple selectable levels LVT(2) Multiple selectable levels Multiple

  12. Multifunctional shape-memory polymers.

    PubMed

    Behl, Marc; Razzaq, Muhammad Yasar; Lendlein, Andreas

    2010-08-17

    The thermally-induced shape-memory effect (SME) is the capability of a material to change its shape in a predefined way in response to heat. In shape-memory polymers (SMP) this shape change is the entropy-driven recovery of a mechanical deformation, which was obtained before by application of external stress and was temporarily fixed by formation of physical crosslinks. The high technological significance of SMP becomes apparent in many established products (e.g., packaging materials, assembling devices, textiles, and membranes) and the broad SMP development activities in the field of biomedical as well as aerospace applications (e.g., medical devices or morphing structures for aerospace vehicles). Inspired by the complex and diverse requirements of these applications fundamental research is aiming at multifunctional SMP, in which SME is combined with additional functions and is proceeding rapidly. In this review different concepts for the creation of multifunctionality are derived from the various polymer network architectures of thermally-induced SMP. Multimaterial systems, such as nanocomposites, are described as well as one-component polymer systems, in which independent functions are integrated. Future challenges will be to transfer the concept of multifunctionality to other emerging shape-memory technologies like light-sensitive SMP, reversible shape changing effects or triple-shape polymers.

  13. Primary and Multisensory Cortical Activity is Correlated with Audiovisual Percepts

    PubMed Central

    Benoit, Margo McKenna; Raij, Tommi; Lin, Fa-Hsuan; Jääskeläinen, Iiro P.; Stufflebeam, Steven

    2012-01-01

    Incongruent auditory and visual stimuli can elicit audiovisual illusions such as the McGurk effect where visual /ka/ and auditory /pa/ fuse into another percept such as/ta/. In the present study, human brain activity was measured with adaptation functional magnetic resonance imaging to investigate which brain areas support such audiovisual illusions. Subjects viewed trains of four movies beginning with three congruent /pa/ stimuli to induce adaptation. The fourth stimulus could be (i) another congruent /pa/, (ii) a congruent /ka/, (iii) an incongruent stimulus that evokes the McGurk effect in susceptible individuals (lips /ka/ voice /pa/), or (iv) the converse combination that does not cause the McGurk effect (lips /pa/ voice/ ka/). This paradigm was predicted to show increased release from adaptation (i.e. stronger brain activation) when the fourth movie and the related percept was increasingly different from the three previous movies. A stimulus change in either the auditory or the visual stimulus from /pa/ to /ka/ (iii, iv) produced within-modality and cross-modal responses in primary auditory and visual areas. A greater release from adaptation was observed for incongruent non-McGurk (iv) compared to incongruent McGurk (iii) trials. A network including the primary auditory and visual cortices, nonprimary auditory cortex, and several multisensory areas (superior temporal sulcus, intraparietal sulcus, insula, and pre-central cortex) showed a correlation between perceiving the McGurk effect and the fMRI signal, suggesting that these areas support the audiovisual illusion. PMID:19780040

  14. Multisensory fusion and the stochastic structure of postural sway.

    PubMed

    Kiemel, Tim; Oie, Kelvin S; Jeka, John J

    2002-10-01

    We analyze the stochastic structure of postural sway and demonstrate that this structure imposes important constraints on models of postural control. Linear stochastic models of various orders were fit to the center-of-mass trajectories of subjects during quiet stance in four sensory conditions: (i) light touch and vision, (ii) light touch, (iii) vision, and (iv) neither touch nor vision. For each subject and condition, the model of appropriate order was determined, and this model was characterized by the eigenvalues and coefficients of its autocovariance function. In most cases, postural-sway trajectories were similar to those produced by a third-order model with eigenvalues corresponding to a slow first-order decay plus a faster-decaying damped oscillation. The slow-decay fraction, which we define as the slow-decay autocovariance coefficient divided by the total variance, was usually near 1. We compare the stochastic structure of our data to two linear control-theory models: (i) a proportional-integral-derivative control model in which the postural system's state is assumed to be known, and (ii) an optimal-control model in which the system's state is estimated based on noisy multisensory information using a Kalman filter. Under certain assumptions, both models have eigenvalues consistent with our results. However, the slow-decay fraction predicted by both models is less than we observe. We show that our results are more consistent with a modification of the optimal-control model in which noise is added to the computations performed by the state estimator. This modified model has a slow-decay fraction near 1 in a parameter regime in which sensory information related to the body's velocity is more accurate than sensory information related to position and acceleration. These findings suggest that: (i) computation noise is responsible for much of the variance observed in postural sway, and (ii) the postural control system under the conditions tested resides in the

  15. Onset of deconfinement in nucleus-nucleus collisions

    SciTech Connect

    Gazdzicki, M.; Gorenstein, M. I.; Seyboth, P.

    2012-05-15

    The energy dependence of hadron production in relativistic nucleus-nucleus collisions reveals anomalies-the kink, horn, and step. They were predicted as signals of the deconfinement phase transition and observed by the NA49 Collaboration in central PbPb collisions at the CERN SPS. This indicates the onset of the deconfinement in nucleus-nucleus collisions at about 30 A GeV.

  16. Integration of semicircular canal and otolith information for multisensory orientation stimuli

    NASA Technical Reports Server (NTRS)

    Ormsby, C. C.; Young, L. R.

    1977-01-01

    This paper presents a model for the perception of dynamic orientation resulting from stimuli which involve both the otoliths and the semicircular canals. The model was applied to several multisensory stimuli and its predictions evaluated. In all cases, the model predictions were in substantial agreement with the known illusions or with the relevant experimental data.

  17. A Teacher's Guide to Multisensory Learning: Improving Literacy by Engaging the Senses

    ERIC Educational Resources Information Center

    Baines, Lawrence

    2008-01-01

    Discover how teachers can motivate students and help them retain more knowledge longer by using sight, sound, smell, taste, touch, and movement in the classroom. In this first-ever guide to multisensory learning, author Lawrence Baines explains how teachers in every grade and subject can change curriculum from a series of assignments to a series…

  18. Temporal limits on rubber hand illusion reflect individuals' temporal resolution in multisensory perception.

    PubMed

    Costantini, Marcello; Robinson, Jeffrey; Migliorati, Daniele; Donno, Brunella; Ferri, Francesca; Northoff, Georg

    2016-12-01

    Synchronous, but not asynchronous, multisensory stimulation has been successfully employed to manipulate the experience of body ownership, as in the case of the rubber hand illusion. Hence, it has been assumed that the rubber hand illusion is bound by the same temporal rules as in multisensory integration. However, empirical evidence of a direct link between the temporal limits on the rubber hand illusion and those on multisensory integration is still lacking. Here we provide the first comprehensive evidence that individual susceptibility to the rubber hand illusion depends upon the individual temporal resolution in multisensory perception, as indexed by the temporal binding window. In particular, in two studies we showed that the degree of temporal asynchrony necessary to prevent the induction of the rubber hand illusion depends upon the individuals' sensitivity to perceiving asynchrony during visuo-tactile stimulation. That is, the larger the temporal binding window, as inferred from a simultaneity judgment task, the higher the level of asynchrony tolerated in the rubber hand illusion. Our results suggest that current neurocognitive models of body ownership can be enriched with a temporal dimension. Moreover, our results suggest that the different aspects of body ownership operate over different time scales.

  19. Temporo-nasal asymmetry in multisensory integration mediated by the Superior Colliculus.

    PubMed

    Bertini, Caterina; Leo, Fabrizio; Làdavas, Elisabetta

    2008-11-25

    Temporo-nasal asymmetry in visual responses has been observed in many behavioural studies. These observations have typically been attributed to the anatomical asymmetry of fibres projecting to the Superior Colliculus (SC), even though this attribution is debated. The present study investigates temporo-nasal asymmetry in multisensory integration, and, by exploiting the absence of S-cone input to the SC, measures a behavioural response dependent strictly on the activity of the SC itself. We used a redundant signal paradigm for simple reaction times, with visual stimuli (red or purple) presented in either the temporal or the nasal hemifield. Participants responded more quickly to concurrent audio-visual (AV) stimuli than to either an auditory or a visual stimulus alone, an established phenomenon known as the Redundant Target Effect (RTE). The nature of this effect was dependent on the colour of the visual stimuli, suggesting its modulation by collicular circuits. When spatially-coincident audio-visual stimuli were visible to the SC (i.e. red stimuli), the RTE depended on a neural coactivation mechanism, suggesting an integration of multisensory information. When using stimuli invisible to the SC (i.e. purple stimuli), the RTE depended only on a simple statistical facilitation effect, in which the two sensory stimuli were processed by independent channels. Finally, we demonstrate that the multisensory integration effect was stronger for stimuli presented to the temporal hemifield than to the nasal hemifield. Taken together, these findings suggested that multisensory stimulation can be differentially effective depending on specific stimulus parameters.

  20. Teaching a foreign language using multisensory structured language techniques to at-risk learners: a review.

    PubMed

    Sparks, R L; Miller, K S

    2000-01-01

    An overview of multisensory structured language (MSL) techniques used to teach a foreign language to at-risk students is outlined. Research supporting the use of MSL techniques is reviewed. Specific activities using the MSL approach to teach the phonology/orthography, grammar and vocabulary of the foreign language as well as reading and communicative activities in the foreign language are presented.

  1. Beta/Gamma Oscillations and Event-Related Potentials Indicate Aberrant Multisensory Processing in Schizophrenia

    PubMed Central

    Balz, Johanna; Roa Romero, Yadira; Keil, Julian; Krebber, Martin; Niedeggen, Michael; Gallinat, Jürgen; Senkowski, Daniel

    2016-01-01

    Recent behavioral and neuroimaging studies have suggested multisensory processing deficits in patients with schizophrenia (SCZ). Thus far, the neural mechanisms underlying these deficits are not well understood. Previous studies with unisensory stimulation have shown altered neural oscillations in SCZ. As such, altered oscillations could contribute to aberrant multisensory processing in this patient group. To test this assumption, we conducted an electroencephalography (EEG) study in 15 SCZ and 15 control participants in whom we examined neural oscillations and event-related potentials (ERPs) in the sound-induced flash illusion (SIFI). In the SIFI multiple auditory stimuli that are presented alongside a single visual stimulus can induce the illusory percept of multiple visual stimuli. In SCZ and control participants we compared ERPs and neural oscillations between trials that induced an illusion and trials that did not induce an illusion. On the behavioral level, SCZ (55.7%) and control participants (55.4%) did not significantly differ in illusion rates. The analysis of ERPs revealed diminished amplitudes and altered multisensory processing in SCZ compared to controls around 135 ms after stimulus onset. Moreover, the analysis of neural oscillations revealed altered 25–35 Hz power after 100 to 150 ms over occipital scalp for SCZ compared to controls. Our findings extend previous observations of aberrant neural oscillations in unisensory perception paradigms. They suggest that altered ERPs and altered occipital beta/gamma band power reflect aberrant multisensory processing in SCZ. PMID:27999553

  2. Multi-sensory Contexts and Support in Science for Special Needs Pupils.

    ERIC Educational Resources Information Center

    Bancroft, Jill

    1999-01-01

    Describes an activity that was adapted from the Chemical Industry Education Center (CIEC) materials for use with special-needs students. The activity, "Transporting Chocolate," addresses a real-world problem and makes use of multisensory contexts to maximize the student's capabilities while minimizing limitations. (WRM)

  3. The maxillary palp of aedes aegypti, a model of multisensory integration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Female yellow-fever mosquitoes, Aedes aegypti, are obligate blood-feeders and vectors of the pathogens that cause dengue fever, yellow fever and Chikungunya. This feeding behavior concludes a series of multisensory events guiding the mosquito to its host from a distance. The antennae and maxillary...

  4. Multisensory aversive stimuli differentially modulate negative feelings in near and far space.

    PubMed

    Taffou, Marine; Ondřej, Jan; O'Sullivan, Carol; Warusfel, Olivier; Dubal, Stéphanie; Viaud-Delmon, Isabelle

    2016-05-05

    Affect, space, and multisensory integration are processes that are closely linked. However, it is unclear whether the spatial location of emotional stimuli interacts with multisensory presentation to influence the emotional experience they induce in the perceiver. In this study, we used the unique advantages of virtual reality techniques to present potentially aversive crowd stimuli embedded in a natural context and to control their display in terms of sensory and spatial presentation. Individuals high in crowdphobic fear navigated in an auditory-visual virtual environment, in which they encountered virtual crowds presented through the visual channel, the auditory channel, or both. They reported the intensity of their negative emotional experience at a far distance and at a close distance from the crowd stimuli. Whereas auditory-visual presentation of close feared stimuli amplified negative feelings, auditory-visual presentation of distant feared stimuli did not amplify negative feelings. This suggests that spatial closeness allows multisensory processes to modulate the intensity of the emotional experience induced by aversive stimuli. Nevertheless, the specific role of auditory stimulation must be investigated to better understand this interaction between multisensory, affective, and spatial representation processes. This phenomenon may serve the implementation of defensive behaviors in response to aversive stimuli that are in position to threaten an individual's feeling of security.

  5. Enhanced multisensory integration and motor reactivation after active motor learning of audiovisual associations.

    PubMed

    Butler, Andrew J; James, Thomas W; James, Karin Harman

    2011-11-01

    Everyday experience affords us many opportunities to learn about objects through multiple senses using physical interaction. Previous work has shown that active motor learning of unisensory items enhances memory and leads to the involvement of motor systems during subsequent perception. However, the impact of active motor learning on subsequent perception and recognition of associations among multiple senses has not been investigated. Twenty participants were included in an fMRI study that explored the impact of active motor learning on subsequent processing of unisensory and multisensory stimuli. Participants were exposed to visuo-motor associations between novel objects and novel sounds either through self-generated actions on the objects or by observing an experimenter produce the actions. Immediately after exposure, accuracy, RT, and BOLD fMRI measures were collected with unisensory and multisensory stimuli in associative perception and recognition tasks. Response times during audiovisual associative and unisensory recognition were enhanced by active learning, as was accuracy during audiovisual associative recognition. The difference in motor cortex activation between old and new associations was greater for the active than the passive group. Furthermore, functional connectivity between visual and motor cortices was stronger after active learning than passive learning. Active learning also led to greater activation of the fusiform gyrus during subsequent unisensory visual perception. Finally, brain regions implicated in audiovisual integration (e.g., STS) showed greater multisensory gain after active learning than after passive learning. Overall, the results show that active motor learning modulates the processing of multisensory associations.

  6. THE USE OF INDIVIDUALIZED MULTISENSORY MATERIALS TO DEVELOP A BASIC SIGHT VOCABULARY.

    ERIC Educational Resources Information Center

    CRAWFORD, FRANCES N.

    TWO SETS OF MULTISENSORY DEVICES WERE USED TO DETERMINE WHETHER THEIR INDIVIDUALIZED USE WOULD HELP RETARDED READERS DEVELOP A BASIC SIGHT VOCABULARY. STUDENTS WHO HAD SPENT 9 OR 10 YEARS IN SCHOOL AND WHO WERE READING AT THE SECOND-READER INSTRUCTIONAL LEVEL WERE GIVEN THE DANIELS WORD RECOGNITION LIST, FORMS A AND B, AS PRETESTS AND POST-TESTS.…

  7. The Effects of Multisensory Imagery in Conjunction with Physical Movement Rehearsal on Golf Putting Performance

    ERIC Educational Resources Information Center

    Ploszay, A. J.; Gentner, Noah B.; Skinner, Christopher H.; Wrisberg, Craig A.

    2006-01-01

    A multiple-baseline design was used to evaluate the effects of a pre-shot putting routine on the putting performance of four NCAA Division I golfers. The routine involved a combination of multisensory imagery and simulated putting movements. Results suggested that the intervention was effective for some participants. Discussion focuses on…

  8. A dynamical framework to relate perceptual variability with multisensory information processing

    PubMed Central

    Thakur, Bhumika; Mukherjee, Abhishek; Sen, Abhijit; Banerjee, Arpan

    2016-01-01

    Multisensory processing involves participation of individual sensory streams, e.g., vision, audition to facilitate perception of environmental stimuli. An experimental realization of the underlying complexity is captured by the “McGurk-effect”- incongruent auditory and visual vocalization stimuli eliciting perception of illusory speech sounds. Further studies have established that time-delay between onset of auditory and visual signals (AV lag) and perturbations in the unisensory streams are key variables that modulate perception. However, as of now only few quantitative theoretical frameworks have been proposed to understand the interplay among these psychophysical variables or the neural systems level interactions that govern perceptual variability. Here, we propose a dynamic systems model consisting of the basic ingredients of any multisensory processing, two unisensory and one multisensory sub-system (nodes) as reported by several researchers. The nodes are connected such that biophysically inspired coupling parameters and time delays become key parameters of this network. We observed that zero AV lag results in maximum synchronization of constituent nodes and the degree of synchronization decreases when we have non-zero lags. The attractor states of this network can thus be interpreted as the facilitator for stabilizing specific perceptual experience. Thereby, the dynamic model presents a quantitative framework for understanding multisensory information processing. PMID:27502974

  9. The impact of multisensory instruction on learning letter names and sounds, word reading, and spelling.

    PubMed

    Schlesinger, Nora W; Gray, Shelley

    2017-03-02

    The purpose of this study was to investigate whether the use of simultaneous multisensory structured language instruction promoted better letter name and sound production, word reading, and word spelling for second grade children with typical development (N = 6) or with dyslexia (N = 5) than structured language instruction alone. The use of non-English graphemes (letters) to represent two pretend languages was used to control for children's lexical knowledge. A multiple baseline, multiple probe across subjects single-case design, with an embedded alternating treatments design, was used to compare the efficacy of multisensory and structured language interventions. Both interventions provided explicit systematic phonics instruction; however, the multisensory intervention also utilized simultaneous engagement of at least two sensory modalities (visual, auditory, and kinesthetic/tactile). Participant's graphed data was visually analyzed, and individual Tau-U and weighted Tau-U effect sizes were calculated for the outcome variables of letter name production, letter sound production, word reading, and word spelling. The multisensory intervention did not provide an advantage over the structured intervention for participants with typical development or dyslexia. However, both interventions had an overall treatment effect for participants with typical development and dyslexia, although intervention effects varied by outcome variable.

  10. Improving Reading and Decoding Skills through the Use of Multisensory Teaching Strategies.

    ERIC Educational Resources Information Center

    O'Dea, Donna

    This paper describes a project for improving the reading and decoding skills of 23 high school students with reading learning disabilities. The targeted population consisted of high school students in a suburban community in the Midwest. The project used Auditory Discrimination in Depth, which is a multisensory program that develops…

  11. Methods for Sight Word Recognition in Kindergarten: Traditional Flashcard Method vs. Multisensory Approach

    ERIC Educational Resources Information Center

    Phillips, William E.; Feng, Jay

    2012-01-01

    A quasi-experimental action research with a pretest-posttest same subject design was implemented to determine if there is a different effect of the flash card method and the multisensory approach on kindergarteners' achievement in sight word recognition, and which method is more effective if there is any difference. Instrumentation for pretest and…

  12. Technologically and Artistically Enhanced Multi-Sensory Computer-Programming Education

    ERIC Educational Resources Information Center

    Katai, Zoltan; Toth, Laszlo

    2010-01-01

    Over the last decades more and more research has analysed relatively new or rediscovered teaching-learning concepts like blended, hybrid, multi-sensory or technologically enhanced learning. This increased interest in these educational forms can be explained by new exciting discoveries in brain research and cognitive psychology, as well as by the…

  13. Effects of Multisensory Environments on Stereotyped Behaviours Assessed as Maintained by Automatic Reinforcement

    ERIC Educational Resources Information Center

    Hill, Lindsay; Trusler, Karen; Furniss, Frederick; Lancioni, Giulio

    2012-01-01

    Background: The aim of the present study was to evaluate the effects of the sensory equipment provided in a multi-sensory environment (MSE) and the level of social contact provided on levels of stereotyped behaviours assessed as being maintained by automatic reinforcement. Method: Stereotyped and engaged behaviours of two young people with severe…

  14. An Empirical Evaluation of an Interactive Multisensory Environment for Children with Disability.

    ERIC Educational Resources Information Center

    Houghton, Stephen; Douglas, Graham; Brigg, John; Langsford, Shane; Powell, Lesley; West, John; Chapman, Annaliese; Kellner, Rick

    1998-01-01

    Seventeen students with severe disability (ages 5 to 18) were assessed on Foundation Outcome Statement (FOS) Skills and subsequently exposed to an interactive multi-sensory environment which included equipment for light and visual stimulation and touch/tactile activities. Students increased in their number of FOS Skills immediately following…

  15. Independent mechanisms for ventriloquism and multisensory integration as revealed by theta-burst stimulation.

    PubMed

    Bertini, Caterina; Leo, Fabrizio; Avenanti, Alessio; Làdavas, Elisabetta

    2010-05-01

    The visual and auditory systems often concur to create a unified perceptual experience and to determine the localization of objects in the external world. Co-occurring auditory and visual stimuli in spatial coincidence are known to enhance performance of auditory localization due to the integration of stimuli from different sensory channels (i.e. multisensory integration). However, auditory localization of audiovisual stimuli presented at spatial disparity might also induce a mislocalization of the sound towards the visual stimulus (i.e. ventriloquism effect). Using repetitive transcranial magnetic stimulation we tested the role of right temporoparietal (rTPC), right occipital (rOC) and right posterior parietal (rPPC) cortex in an auditory localization task in which indices of ventriloquism and multisensory integration were computed. We found that suppression of rTPC excitability by means of continuous theta-burst stimulation (cTBS) reduced multisensory integration. No similar effect was found for cTBS over rOC. Moreover, inhibition of rOC, but not of rTPC, suppressed the visual bias in the contralateral hemifield. In contrast, cTBS over rPPC did not produce any modulation of ventriloquism or integrative effects. The double dissociation found in the present study suggests that ventriloquism and audiovisual multisensory integration are functionally independent phenomena and may be underpinned by partially different neural circuits.

  16. Beta/Gamma Oscillations and Event-Related Potentials Indicate Aberrant Multisensory Processing in Schizophrenia.

    PubMed

    Balz, Johanna; Roa Romero, Yadira; Keil, Julian; Krebber, Martin; Niedeggen, Michael; Gallinat, Jürgen; Senkowski, Daniel

    2016-01-01

    Recent behavioral and neuroimaging studies have suggested multisensory processing deficits in patients with schizophrenia (SCZ). Thus far, the neural mechanisms underlying these deficits are not well understood. Previous studies with unisensory stimulation have shown altered neural oscillations in SCZ. As such, altered oscillations could contribute to aberrant multisensory processing in this patient group. To test this assumption, we conducted an electroencephalography (EEG) study in 15 SCZ and 15 control participants in whom we examined neural oscillations and event-related potentials (ERPs) in the sound-induced flash illusion (SIFI). In the SIFI multiple auditory stimuli that are presented alongside a single visual stimulus can induce the illusory percept of multiple visual stimuli. In SCZ and control participants we compared ERPs and neural oscillations between trials that induced an illusion and trials that did not induce an illusion. On the behavioral level, SCZ (55.7%) and control participants (55.4%) did not significantly differ in illusion rates. The analysis of ERPs revealed diminished amplitudes and altered multisensory processing in SCZ compared to controls around 135 ms after stimulus onset. Moreover, the analysis of neural oscillations revealed altered 25-35 Hz power after 100 to 150 ms over occipital scalp for SCZ compared to controls. Our findings extend previous observations of aberrant neural oscillations in unisensory perception paradigms. They suggest that altered ERPs and altered occipital beta/gamma band power reflect aberrant multisensory processing in SCZ.

  17. The recalibration patterns of perceptual synchrony and multisensory integration after exposure to asynchronous speech.

    PubMed

    Yuan, Xiangyong; Bi, Cuihua; Yin, Huazhan; Li, Baolin; Huang, Xiting

    2014-05-21

    Perceptual synchrony and multisensory integration both vary as a function of stimulus onset asynchrony, but evidences from behavioral, patient, and lesion studies all support some dissociation between these two processes. Although it has been found that both perceptual synchrony and multisensory integration are recalibrated after exposure to asynchronous multisensory stimuli, no studies have directly compared these two recalibration patterns. We addressed this by using McGurk speech and requiring participants to perform simultaneity judgments and a syllable identification task in separate sessions. The results revealed that after exposure to asynchrony, both perceptual synchrony and McGurk fusion shifted toward the temporal lag. The recalibration aftereffects (i.e., the magnitude of shifts) of these two processes have no significant difference and correlation. In addition, McGurk fusion increased strongly at the direction of the temporal lag, which could not be fully explained by fusion shifts. Thus, the present research implies that recalibration patterns of explicit and implicit timing represented by perceptual synchrony and multisensory integration have both similarity and difference.

  18. A Multisensory Language Approach to the Introduction of the Alphabet to Hearing Impaired Preschoolers.

    ERIC Educational Resources Information Center

    Jaworski, Anne Porter; Schroder, Ann

    The project was designed to develop a multisensory, language-oriented curriculum to introduce the letters of the alphabet to six hearing impaired preschoolers. Every week a new letter is introduced via such tasks as art and cooking activities, snacks, beginning sound picture cards, yarn and lacing letters, sandpaper letters, alphabet string beads,…

  19. Assessing the Role of the ‘Unity Assumption’ on Multisensory Integration: A Review

    PubMed Central

    Chen, Yi-Chuan; Spence, Charles

    2017-01-01

    There has been longstanding interest from both experimental psychologists and cognitive neuroscientists in the potential modulatory role of various top–down factors on multisensory integration/perception in humans. One such top–down influence, often referred to in the literature as the ‘unity assumption,’ is thought to occur in those situations in which an observer considers that various of the unisensory stimuli that they have been presented with belong to one and the same object or event (Welch and Warren, 1980). Here, we review the possible factors that may lead to the emergence of the unity assumption. We then critically evaluate the evidence concerning the consequences of the unity assumption from studies of the spatial and temporal ventriloquism effects, from the McGurk effect, and from the Colavita visual dominance paradigm. The research that has been published to date using these tasks provides support for the claim that the unity assumption influences multisensory perception under at least a subset of experimental conditions. We then consider whether the notion has been superseded in recent years by the introduction of priors in Bayesian causal inference models of human multisensory perception. We suggest that the prior of common cause (that is, the prior concerning whether multisensory signals originate from the same source or not) offers the most useful way to quantify the unity assumption as a continuous cognitive variable.

  20. Microcontroller based fibre-optic visual presentation system for multisensory neuroimaging.

    PubMed

    Kurniawan, Veldri; Klemen, Jane; Chambers, Christopher D

    2011-10-30

    Presenting visual stimuli in physical 3D space during fMRI experiments carries significant technical challenges. Certain types of multisensory visuotactile experiments and visuomotor tasks require presentation of visual stimuli in peripersonal space, which cannot be accommodated by ordinary projection screens or binocular goggles. However, light points produced by a group of LEDs can be transmitted through fibre-optic cables and positioned anywhere inside the MRI scanner. Here we describe the design and implementation of a microcontroller-based programmable digital device for controlling fibre-optically transmitted LED lights from a PC. The main feature of this device is the ability to independently control the colour, brightness, and timing of each LED. Moreover, the device was designed in a modular and extensible way, which enables easy adaptation for various experimental paradigms. The device was tested and validated in three fMRI experiments involving basic visual perception, a simple colour discrimination task, and a blocked multisensory visuo-tactile task. The results revealed significant lateralized activation in occipital cortex of all participants, a reliable response in ventral occipital areas to colour stimuli elicited by the device, and strong activations in multisensory brain regions in the multisensory task. Overall, these findings confirm the suitability of this device for presenting complex fibre-optic visual and cross-modal stimuli inside the scanner.

  1. Multisensory adaptation of spatial-to-motor transformations in children with developmental coordination disorder.

    PubMed

    King, Bradley R; Kagerer, Florian A; Harring, Jeffrey R; Contreras-Vidal, Jose L; Clark, Jane E

    2011-07-01

    Recent research has demonstrated that adaptation to a visuomotor distortion systematically influenced movements to auditory targets in adults and typically developing (TD) children, suggesting that the adaptation of spatial-to-motor transformations for reaching movements is multisensory (i.e., generalizable across sensory modalities). The multisensory characteristics of these transformations in children with developmental coordination disorder (DCD) have not been examined. Given that previous research has demonstrated that children with DCD have deficits in sensorimotor integration, these children may also have impairments in the formation of multisensory spatial-to-motor transformations for target-directed arm movements. To investigate this hypothesis, children with and without DCD executed discrete arm movements to visual and acoustic targets prior to and following exposure to an abrupt visual feedback rotation. Results demonstrated that the magnitudes of the visual aftereffects were equivalent in the TD children and the children with DCD, indicating that both groups of children adapted similarly to the visuomotor perturbation. Moreover, the influence of visuomotor adaptation on auditory-motor performance was similar in the two groups of children. This suggests that the multisensory processes underlying adaptation of spatial-to-motor transformations are similar in children with DCD and TD children.

  2. Program Evaluation of a School District's Multisensory Reading Initiative

    ERIC Educational Resources Information Center

    Asip, Michael Patrick

    2012-01-01

    The purpose of this study was to conduct a formative program evaluation of a school district's multisensory reading initiative. The mixed methods study involved semi-structured interviews, online survey, focus groups, document review, and analysis of extant special education student reading achievement data. Participants included elementary…

  3. Multi-Sensory Storytelling: A Tool for Teaching or an Intervention Technique?

    ERIC Educational Resources Information Center

    Preece, David; Zhao, Yu

    2015-01-01

    This article reports on research undertaken to investigate how multi-sensory storytelling (MSST) was being used within schools for students with profound and multiple learning difficulties and other special educational needs. Semi-structured interviews (n?=?27) and observations (n?=?18) were undertaken in five schools in the East Midlands and…

  4. A Multisensory Aquatic Environment for Individuals with Intellectual/Developmental Disabilities

    ERIC Educational Resources Information Center

    Potter, Cindy; Erzen, Carol

    2008-01-01

    This article presents the eighth of a 12-part series exploring the benefits of aquatic therapy and recreation for people with special needs. Here, the authors describe the process of development and installation of an aquatic multisensory environment (MSE) and the many factors that one should consider for a successful result. There are many…

  5. Locally rare species influence grassland ecosystem multifunctionality.

    PubMed

    Soliveres, Santiago; Manning, Peter; Prati, Daniel; Gossner, Martin M; Alt, Fabian; Arndt, Hartmut; Baumgartner, Vanessa; Binkenstein, Julia; Birkhofer, Klaus; Blaser, Stefan; Blüthgen, Nico; Boch, Steffen; Böhm, Stefan; Börschig, Carmen; Buscot, Francois; Diekötter, Tim; Heinze, Johannes; Hölzel, Norbert; Jung, Kirsten; Klaus, Valentin H; Klein, Alexandra-Maria; Kleinebecker, Till; Klemmer, Sandra; Krauss, Jochen; Lange, Markus; Morris, E Kathryn; Müller, Jörg; Oelmann, Yvonne; Overmann, Jörg; Pašalić, Esther; Renner, Swen C; Rillig, Matthias C; Schaefer, H Martin; Schloter, Michael; Schmitt, Barbara; Schöning, Ingo; Schrumpf, Marion; Sikorski, Johannes; Socher, Stephanie A; Solly, Emily F; Sonnemann, Ilja; Sorkau, Elisabeth; Steckel, Juliane; Steffan-Dewenter, Ingolf; Stempfhuber, Barbara; Tschapka, Marco; Türke, Manfred; Venter, Paul; Weiner, Christiane N; Weisser, Wolfgang W; Werner, Michael; Westphal, Catrin; Wilcke, Wolfgang; Wolters, Volkmar; Wubet, Tesfaye; Wurst, Susanne; Fischer, Markus; Allan, Eric

    2016-05-19

    Species diversity promotes the delivery of multiple ecosystem functions (multifunctionality). However, the relative functional importance of rare and common species in driving the biodiversity-multifunctionality relationship remains unknown. We studied the relationship between the diversity of rare and common species (according to their local abundances and across nine different trophic groups), and multifunctionality indices derived from 14 ecosystem functions on 150 grasslands across a land-use intensity (LUI) gradient. The diversity of above- and below-ground rare species had opposite effects, with rare above-ground species being associated with high levels of multifunctionality, probably because their effects on different functions did not trade off against each other. Conversely, common species were only related to average, not high, levels of multifunctionality, and their functional effects declined with LUI. Apart from the community-level effects of diversity, we found significant positive associations between the abundance of individual species and multifunctionality in 6% of the species tested. Species-specific functional effects were best predicted by their response to LUI: species that declined in abundance with land use intensification were those associated with higher levels of multifunctionality. Our results highlight the importance of rare species for ecosystem multifunctionality and help guiding future conservation priorities.

  6. Effects of Aging in Multisensory Integration: A Systematic Review

    PubMed Central

    de Dieuleveult, Alix L.; Siemonsma, Petra C.; van Erp, Jan B. F.; Brouwer, Anne-Marie

    2017-01-01

    Multisensory integration (MSI) is the integration by the brain of environmental information acquired through more than one sense. Accurate MSI has been shown to be a key component of successful aging and to be crucial for processes underlying activities of daily living (ADLs). Problems in MSI could prevent older adults (OA) to age in place and live independently. However, there is a need to know how to assess changes in MSI in individuals. This systematic review provides an overview of tests assessing the effect of age on MSI in the healthy elderly population (aged 60 years and older). A literature search was done in Scopus. Articles from the earliest records available to January 20, 2016, were eligible for inclusion if assessing effects of aging on MSI in the healthy elderly population compared to younger adults (YA). These articles were rated for risk of bias with the Newcastle-Ottawa quality assessment. Out of 307 identified research articles, 49 articles were included for final review, describing 69 tests. The review indicated that OA maximize the use of multiple sources of information in comparison to YA (20 studies). In tasks that require more cognitive function, or when participants need to adapt rapidly to a situation, or when a dual task is added to the experiment, OA have problems selecting and integrating information properly as compared to YA (19 studies). Additionally, irrelevant or wrong information (i.e., distractors) has a greater impact on OA than on YA (21 studies). OA failing to weigh sensory information properly, has not been described in previous reviews. Anatomical changes (i.e., reduction of brain volume and differences of brain areas’ recruitment) and information processing changes (i.e., general cognitive slowing, inverse effectiveness, larger time window of integration, deficits in attentional control and increased noise at baseline) can only partly explain the differences between OA and YA regarding MSI. Since we have an interest in

  7. Generic Automated Multi-function Finger Design

    NASA Astrophysics Data System (ADS)

    Honarpardaz, M.; Tarkian, M.; Sirkett, D.; Ölvander, J.; Feng, X.; Elf, J.; Sjögren, R.

    2016-11-01

    Multi-function fingers that are able to handle multiple workpieces are crucial in improvement of a robot workcell. Design automation of multi-function fingers is highly demanded by robot industries to overcome the current iterative, time consuming and complex manual design process. However, the existing approaches for the multi-function finger design automation are unable to entirely meet the robot industries’ need. This paper proposes a generic approach for design automation of multi-function fingers. The proposed approach completely automates the design process and requires no expert skill. In addition, this approach executes the design process much faster than the current manual process. To validate the approach, multi-function fingers are successfully designed for two case studies. Further, the results are discussed and benchmarked with existing approaches.

  8. Multisensory Stimulation to Improve Low- and Higher-Level Sensory Deficits after Stroke: A Systematic Review.

    PubMed

    Tinga, Angelica Maria; Visser-Meily, Johanna Maria Augusta; van der Smagt, Maarten Jeroen; Van der Stigchel, Stefan; van Ee, Raymond; Nijboer, Tanja Cornelia Wilhelmina

    2016-03-01

    The aim of this systematic review was to integrate and assess evidence for the effectiveness of multisensory stimulation (i.e., stimulating at least two of the following sensory systems: visual, auditory, and somatosensory) as a possible rehabilitation method after stroke. Evidence was considered with a focus on low-level, perceptual (visual, auditory and somatosensory deficits), as well as higher-level, cognitive, sensory deficits. We referred to the electronic databases Scopus and PubMed to search for articles that were published before May 2015. Studies were included which evaluated the effects of multisensory stimulation on patients with low- or higher-level sensory deficits caused by stroke. Twenty-one studies were included in this review and the quality of these studies was assessed (based on eight elements: randomization, inclusion of control patient group, blinding of participants, blinding of researchers, follow-up, group size, reporting effect sizes, and reporting time post-stroke). Twenty of the twenty-one included studies demonstrate beneficial effects on low- and/or higher-level sensory deficits after stroke. Notwithstanding these beneficial effects, the quality of the studies is insufficient for valid conclusion that multisensory stimulation can be successfully applied as an effective intervention. A valuable and necessary next step would be to set up well-designed randomized controlled trials to examine the effectiveness of multisensory stimulation as an intervention for low- and/or higher-level sensory deficits after stroke. Finally, we consider the potential mechanisms of multisensory stimulation for rehabilitation to guide this future research.

  9. Multifunctional Nanoprobes for Cancer Cell Targeting, Imaging and Anticancer Drug Delivery

    NASA Astrophysics Data System (ADS)

    Linkov, Pavel; Laronze-Cochard, Marie; Sapi, Janos; Sidorov, Lev N.; Nabiev, Igor

    The diagnosis and treatment of cancer have been greatly improved with recent developments in bio-nanotechnology, including engineering of multifunctional probes. One of the promising nanoscale tools for cancer imaging is fluorescent quantum dots (QDs), whose small size and unique optical properties allow them to penetrate into cells and ensure highly sensitive optical diagnosis of cancer at the cellular level. Furthermore, novel multi-functional probes have been developed in which QDs are conjugated with one or several functional molecules, including targeting moieties and therapeutic agents. Here, the strategy for engineering novel nanocarriers for controlled nucleus-targeted antitumor drug delivery and real-time imaging by single- or two-photon microscopy is described. A triple multifunctional nanoprobe is being developed that consists of a nitrogen-based heterocyclic derivative, an anticancer agent interacting with a DNA in living cells; a recognized molecule serving as a vector responsible for targeted delivery of the probe into cancer cells; and photoluminescent QDs providing the imaging capability of the probe. Subsequent optimization of the multifunctional nanoprobe will offer new possibilities for cancer diagnosis and treatment.

  10. Phototriggered multifunctional drug delivery device

    NASA Astrophysics Data System (ADS)

    Härtner, S.; Kim, H.-C.; Hampp, N.

    2006-02-01

    Although phototriggered cleavage of chemical bonds induced by single-photon or two-photon-absorption provides attractive tools for controlled drug delivery, the choice of drugs is still limited by the linker system to which the therapeutic molecules need to be bound covalently. The use of a multifunctional linker system suitable for coupling a broad spectrum of drugs to the polymeric carrier will open a new field for drug delivery. We have developed a novel photocleavable multifunctional linker system based on coumarin dimers, whose unique photochemical behavior are well characterized. As a first example, an acrylic polymer-drug conjugate with antimetabolites is explored. The cleavage of the link between the drug and the polymer backbone is triggered by both single- as well as two-photon absorption. The release of the drug is investigated. It is possible to manufacture a polymeric drug delivery device with several drugs in different areas. In particular the two-photon-absorption induced process offers the possibility to address the drug of interest owing to the superior spatial resolution. The key to such devices is a versatile linker-system which can be adopted to work with various drug compounds.

  11. Electrospun multifunctional tissue engineering scaffolds

    NASA Astrophysics Data System (ADS)

    Wang, Chong; Wang, Min

    2014-03-01

    Tissue engineering holds great promises in providing successful treatments of human body tissue loss that current methods are unable to treat or unable to achieve satisfactory clinical outcomes. In scaffold-based tissue engineering, a highperformance scaffold underpins the success of a tissue engineering strategy and a major direction in the field is to create multifunctional tissue engineering scaffolds for enhanced biological performance and for regenerating complex body tissues. Electrospinning can produce nanofibrous scaffolds that are highly desirable for tissue engineering. The enormous interest in electrospinning and electrospun fibrous structures by the science, engineering and medical communities has led to various developments of the electrospinning technology and wide investigations of electrospun products in many industries, including biomedical engineering, over the past two decades. It is now possible to create novel, multicomponent tissue engineering scaffolds with multiple functions. This article provides a concise review of recent advances in the R & D of electrospun multifunctional tissue engineering scaffolds. It also presents our philosophy and research in the designing and fabrication of electrospun multicomponent scaffolds with multiple functions.

  12. Bi- or multifunctional peptide drugs

    PubMed Central

    Schiller, Peter W.

    2009-01-01

    Strategies for the design of bi- or multifunctional drugs are reviewed. A distinction is made between bifunctional drugs interacting in a monovalent fashion with two targets and ligands containing two distinct pharmacophores binding in a bivalent mode to the two binding sites in a receptor heterodimer. Arguments are presented to indicate that some of the so-called “bivalent” ligands reported in the literature are unlikely to simultaneously interact with two binding sites. Aspects related to the development of bi- or multifunctional drugs are illustrated with examples from the field of opioid analgesics. The drug-like properties of the tetrapeptide Dmt1[DALDA] with triple action as a μ opioid agonist, norepinephrine uptake inhibitor and releaser of endogenous opioid peptides to produce potent spinal analgesia are reviewed. Rationales for the development of opioid peptides with mixed agonist/antagonist profiles as analgesics with reduced side effects are presented. Progress in the development of mixed μ opioid agonist/δ opioid antagonists with low propensity to produce tolerance and physical dependence is reviewed. Efforts to develop bifunctional peptides containing a μ opioid agonist and a cholecystokinin antagonist or an NK1 receptor antagonist as analgesics expected to produce less tolerance and dependence are also reviewed. A strategy to improve the drug-like properties of bifunctional opioid peptide analgesics is presented. PMID:19285088

  13. Nuclear-Targeted Multifunctional Magnetic Nanoparticles for Photothermal Therapy.

    PubMed

    Peng, Haibao; Tang, Jing; Zheng, Rui; Guo, Guannan; Dong, Angang; Wang, Yajun; Yang, Wuli

    2017-01-27

    The pursuit of multifunctional, innovative, more efficient, and safer cancer treatment has gained increasing interest in the research of preclinical nanoparticle-mediated photothermal therapy (PTT). Cell nucleus is recognized as the ideal target for cancer treatment because it plays a central role in genetic information and the transcription machinery reside. In this work, an efficient nuclear-targeted PTT strategy is proposed using transferrin and TAT peptide (TAT: YGRKKRRQRRR) conjugated monodisperse magnetic nanoparticles, which can be readily functionalized and stabilized for potential diagnostic and therapeutic applications. The monodisperse magnetic nanoparticles exhibit high photothermal conversion efficiency (≈37%) and considerable photothermal stability. They also show a high magnetization value and transverse relaxivity (207.1 mm(-1) s(-1) ), which could be applied for magnetic resonance imaging. The monodisperse magnetic nanoparticles conjugated with TAT peptides can efficiently target the nucleus and achieve the imaging-guided function, efficient cancer cells killing ability. Therefore, this work may present a practicable strategy to develop subcellular organelle targeted PTT agents for simultaneous cancer targeting, imaging, and therapy.

  14. The variability of multisensory processes of natural stimuli in human and non-human primates in a detection task

    PubMed Central

    Juan, Cécile; Cappe, Céline; Alric, Baptiste; Roby, Benoit; Gilardeau, Sophie; Barone, Pascal; Girard, Pascal

    2017-01-01

    Background Behavioral studies in both human and animals generally converge to the dogma that multisensory integration improves reaction times (RTs) in comparison to unimodal stimulation. These multisensory effects depend on diverse conditions among which the most studied were the spatial and temporal congruences. Further, most of the studies are using relatively simple stimuli while in everyday life, we are confronted to a large variety of complex stimulations constantly changing our attentional focus over time, a modality switch that can impact on stimuli detection. In the present study, we examined the potential sources of the variability in reaction times and multisensory gains with respect to the intrinsic features of a large set of natural stimuli. Methodology/Principle findings Rhesus macaque monkeys and human subjects performed a simple audio-visual stimulus detection task in which a large collection of unimodal and bimodal natural stimuli with semantic specificities was presented at different saliencies. Although we were able to reproduce the well-established redundant signal effect, we failed to reveal a systematic violation of the race model which is considered to demonstrate multisensory integration. In both monkeys and human species, our study revealed a large range of multisensory gains, with negative and positive values. While modality switch has clear effects on reaction times, one of the main causes of the variability of multisensory gains appeared to be linked to the intrinsic physical parameters of the stimuli. Conclusion/Significance Based on the variability of multisensory benefits, our results suggest that the neuronal mechanisms responsible of the redundant effect (interactions vs. integration) are highly dependent on the stimulus complexity suggesting different implications of uni- and multisensory brain regions. Further, in a simple detection task, the semantic values of individual stimuli tend to have no significant impact on task

  15. Keeping in touch with the visual system: spatial alignment and multisensory integration of visual-somatosensory inputs

    PubMed Central

    Mahoney, Jeannette R.; Molholm, Sophie; Butler, John S.; Sehatpour, Pejman; Gomez-Ramirez, Manuel; Ritter, Walter; Foxe, John J.

    2015-01-01

    Correlated sensory inputs coursing along the individual sensory processing hierarchies arrive at multisensory convergence zones in cortex where inputs are processed in an integrative manner. The exact hierarchical level of multisensory convergence zones and the timing of their inputs are still under debate, although increasingly, evidence points to multisensory integration (MSI) at very early sensory processing levels. While MSI is said to be governed by stimulus properties including space, time, and magnitude, violations of these rules have been documented. The objective of the current study was to determine, both psychophysically and electrophysiologically, whether differential visual-somatosensory (VS) integration patterns exist for stimuli presented to the same versus opposite hemifields. Using high-density electrical mapping and complementary psychophysical data, we examined multisensory integrative processing for combinations of visual and somatosensory inputs presented to both left and right spatial locations. We assessed how early during sensory processing VS interactions were seen in the event-related potential and whether spatial alignment of the visual and somatosensory elements resulted in differential integration effects. Reaction times to all VS pairings were significantly faster than those to the unisensory conditions, regardless of spatial alignment, pointing to engagement of integrative multisensory processing in all conditions. In support, electrophysiological results revealed significant differences between multisensory simultaneous VS and summed V + S responses, regardless of the spatial alignment of the constituent inputs. Nonetheless, multisensory effects were earlier in the aligned conditions, and were found to be particularly robust in the case of right-sided inputs (beginning at just 55 ms). In contrast to previous work on audio-visual and audio-somatosensory inputs, the current work suggests a degree of spatial specificity to the earliest

  16. Keeping in touch with the visual system: spatial alignment and multisensory integration of visual-somatosensory inputs.

    PubMed

    Mahoney, Jeannette R; Molholm, Sophie; Butler, John S; Sehatpour, Pejman; Gomez-Ramirez, Manuel; Ritter, Walter; Foxe, John J

    2015-01-01

    Correlated sensory inputs coursing along the individual sensory processing hierarchies arrive at multisensory convergence zones in cortex where inputs are processed in an integrative manner. The exact hierarchical level of multisensory convergence zones and the timing of their inputs are still under debate, although increasingly, evidence points to multisensory integration (MSI) at very early sensory processing levels. While MSI is said to be governed by stimulus properties including space, time, and magnitude, violations of these rules have been documented. The objective of the current study was to determine, both psychophysically and electrophysiologically, whether differential visual-somatosensory (VS) integration patterns exist for stimuli presented to the same versus opposite hemifields. Using high-density electrical mapping and complementary psychophysical data, we examined multisensory integrative processing for combinations of visual and somatosensory inputs presented to both left and right spatial locations. We assessed how early during sensory processing VS interactions were seen in the event-related potential and whether spatial alignment of the visual and somatosensory elements resulted in differential integration effects. Reaction times to all VS pairings were significantly faster than those to the unisensory conditions, regardless of spatial alignment, pointing to engagement of integrative multisensory processing in all conditions. In support, electrophysiological results revealed significant differences between multisensory simultaneous VS and summed V + S responses, regardless of the spatial alignment of the constituent inputs. Nonetheless, multisensory effects were earlier in the aligned conditions, and were found to be particularly robust in the case of right-sided inputs (beginning at just 55 ms). In contrast to previous work on audio-visual and audio-somatosensory inputs, the current work suggests a degree of spatial specificity to the earliest

  17. Neutrino-nucleus interactions

    SciTech Connect

    Gallagher, H.; Garvey, G.; Zeller, G.P.; /Fermilab

    2011-01-01

    The study of neutrino oscillations has necessitated a new generation of neutrino experiments that are exploring neutrino-nuclear scattering processes. We focus in particular on charged-current quasi-elastic scattering, a particularly important channel that has been extensively investigated both in the bubble-chamber era and by current experiments. Recent results have led to theoretical reexamination of this process. We review the standard picture of quasi-elastic scattering as developed in electron scattering, review and discuss experimental results, and discuss additional nuclear effects such as exchange currents and short-range correlations that may play a significant role in neutrino-nucleus scattering.

  18. Reality of comet nucleus.

    NASA Technical Reports Server (NTRS)

    Lyttleton, R. A.

    1972-01-01

    The prime problem of a comet mission must be to settle whether the cometary nucleus has an actual tangible material existence, or whether it arises from some optical effect present only at times within comets. The absence of any large particles in a comet seems to be demonstrated by certain meteor showers. A feature that would seem to indicate that a comet consists primarily of a swarm of particles is that the coma in general contracts as the comet approaches the sun, roughly in proportion within the distance, and then expands again as it recedes.

  19. Nucleus from string theory

    NASA Astrophysics Data System (ADS)

    Hashimoto, Koji; Morita, Takeshi

    2011-08-01

    In generic holographic QCD, we find that baryons are bound to form a nucleus, and that its radius obeys the empirically-known mass-number (A) dependence r∝A1/3 for large A. Our result is robust, since we use only a generic property of D-brane actions in string theory. We also show that nucleons are bound completely in a finite volume. Furthermore, employing a concrete holographic model (derived by Hashimoto, Iizuka, and Yi, describing a multibaryon system in the Sakai-Sugimoto model), the nuclear radius is evaluated as O(1)×A1/3[fm], which is consistent with experiments.

  20. Higgs-boson production in nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

    Norbury, J. W.; Townsend, L. W. (Principal Investigator)

    1990-01-01

    Cross-section calculations are presented for the production of intermediate-mass Higgs bosons produced in ultrarelativistic nucleus-nucleus collisions via two-photon fusion. The calculations are performed in position space using Baur's method for folding together the Weizsacker-Williams virtual-photon spectra of the two colliding nuclei. It is found that two-photon fusion in nucleus-nucleus collisions is a plausible way of finding intermediate-mass Higgs bosons at the Superconducting Super Collider or the CERN Large Hadron Collider.

  1. Higgs-Boson Production in Nucleus-Nucleus Collisions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    1992-01-01

    Cross section calculations are presented for the production of intermediate-mass Higgs bosons produced in ultrarelativistic nucleus-nucleus collisions via two photon fusion. The calculations are performed in position space using Baur's method for folding together the Weizsacker-Williams virtual-photon spectra of the two colliding nuclei. It is found that two photon fusion in nucleus-nucleus collisions is a plausible way of finding intermediate-mass Higgs bosons at the Superconducting Super Collider or the CERN Large Hadron Collider.

  2. CCD Multi-Function Processor Test Bed.

    DTIC Science & Technology

    1982-01-01

    AD-A111 335 MITRE CORP BEDFORDMA F/6 9/5 CCD MULTIFUNCTION PROCESSOR TEST BED.(U) JAN 82 M W PACZAN. S M WALOSTEIN F19628-81-C-OO01 UNCLASSIFIED MTR...HAIAf III 4 ESD-TR-81-394 MTR-8417 CCD MULTI-FUNCTION PROCESSOR TEST BED By M. W. Paczan and S. M. Waldstein JANUARY 1982 Prepared for DEPUTY FOR...TITLE (and Subtitle) 5. TYPE OF REPORT & PERIOD COVERED CCD MULTI-FUNCTION PROCESSOR TEST BED 6. PERFORMING ORG. REPORT NUMBER MTR-8417 7 AUT-OR(s) S

  3. Networking the nucleus

    PubMed Central

    Rajapakse, Indika; Scalzo, David; Tapscott, Stephen J; Kosak, Steven T; Groudine, Mark

    2010-01-01

    The nuclei of differentiating cells exhibit several fundamental principles of self-organization. They are composed of many dynamical units connected physically and functionally to each other—a complex network—and the different parts of the system are mutually adapted and produce a characteristic end state. A unique cell-specific signature emerges over time from complex interactions among constituent elements that delineate coordinate gene expression and chromosome topology. Each element itself consists of many interacting components, all dynamical in nature. Self-organizing systems can be simplified while retaining complex information using approaches that examine the relationship between elements, such as spatial relationships and transcriptional information. These relationships can be represented using well-defined networks. We hypothesize that during the process of differentiation, networks within the cell nucleus rewire according to simple rules, from which a higher level of order emerges. Studying the interaction within and among networks provides a useful framework for investigating the complex organization and dynamic function of the nucleus. PMID:20664641

  4. Multifunctionalities driven by ferroic domains

    SciTech Connect

    Yang, J. C.; Huang, Y. L.; Chu, Y. H.; He, Q.

    2014-08-14

    Considerable attention has been paid to ferroic systems in pursuit of advanced applications in past decades. Most recently, the emergence and development of multiferroics, which exhibit the coexistence of different ferroic natures, has offered a new route to create functionalities in the system. In this manuscript, we step from domain engineering to explore a roadmap for discovering intriguing phenomena and multifunctionalities driven by periodic domain patters. As-grown periodic domains, offering exotic order parameters, periodic local perturbations and the capability of tailoring local spin, charge, orbital and lattice degrees of freedom, are introduced as modeling templates for fundamental studies and novel applications. We discuss related significant findings on ferroic domain, nanoscopic domain walls, and conjunct heterostructures based on the well-organized domain patterns, and end with future prospects and challenges in the field.

  5. Synthetic approaches to multifunctional indenes

    PubMed Central

    López-Pérez, Sara; Dinarès, Immaculada

    2011-01-01

    Summary The synthesis of multifunctional indenes with at least two different functional groups has not yet been extensively explored. Among the plausible synthetic routes to 3,5-disubstituted indenes bearing two different functional groups, such as the [3-(aminoethyl)inden-5-yl)]amines, a reasonable pathway involves the (5-nitro-3-indenyl)acetamides as key intermediates. Although several multistep synthetic approaches can be applied to obtain these advanced intermediates, we describe herein their preparation by an aldol-type reaction between 5-nitroindan-1-ones and the lithium salt of N,N-disubstituted acetamides, followed immediately by dehydration with acid. This classical condensation process, which is neither simple nor trivial despite its apparent directness, permits an efficient entry to a variety of indene-based molecular modules, which could be adapted to a range of functionalized indanones. PMID:22238553

  6. Toward multifunctional "clickable" diamond nanoparticles.

    PubMed

    Khanal, Manakamana; Turcheniuk, Volodymyr; Barras, Alexandre; Rosay, Elodie; Bande, Omprakash; Siriwardena, Aloysius; Zaitsev, Vladimir; Pan, Guo-Hui; Boukherroub, Rabah; Szunerits, Sabine

    2015-04-07

    Nanodiamonds (NDs) are among the most promising new carbon based materials for biomedical applications, and the simultaneous integration of various functions onto NDs is an urgent necessity. A multifunctional nanodiamond based formulation is proposed here. Our strategy relies on orthogonal surface modification using different dopamine anchors. NDs simultaneously functionalized with triethylene glycol (EG) and azide (-N3) functions were fabricated through a stoichiometrically controlled integration of the dopamine ligands onto the surface of hydroxylated NDs. The presence of EG functionalities rendered NDs soluble in water and biological media, while the -N3 group allowed postsynthetic modification of the NDs using "click" chemistry. As a proof of principle, alkynyl terminated di(amido amine) ligands were linked to these ND particles.

  7. Multifunctional composites for energy storage

    NASA Astrophysics Data System (ADS)

    Shuvo, Mohammad Arif I.; Karim, Hasanul; Rajib, Md; Delfin, Diego; Lin, Yirong

    2014-03-01

    Electrochemical super-capacitors have become one of the most important topics in both academia and industry as novel energy storage devices because of their high power density, long life cycles, and high charge/discharge efficiency. Recently, there has been an increasing interest in the development of multifunctional structural energy storage devices such as structural super-capacitors for applications in aerospace, automobiles and portable electronics. These multifunctional structural super-capacitors provide lighter structures combining energy storage and load bearing functionalities. Due to their superior materials properties, carbon fiber composites have been widely used in structural applications for aerospace and automotive industries. Besides, carbon fiber has good electrical conductivity which will provide lower equivalent series resistance; therefore, it can be an excellent candidate for structural energy storage applications. Hence, this paper is focused on performing a pilot study for using nanowire/carbon fiber hybrids as building materials for structural energy storage materials; aiming at enhancing the charge/discharge rate and energy density. This hybrid material combines the high specific surface area of carbon fiber and pseudo-capacitive effect of metal oxide nanowires which were grown hydrothermally in an aligned fashion on carbon fibers. The aligned nanowire array could provide a higher specific surface area that leads to high electrode-electrolyte contact area and fast ion diffusion rates. Scanning Electron Microscopy (SEM) and XRay Diffraction (XRD) measurements were used for the initial characterization of this nanowire/carbon fiber hybrid material system. Electrochemical testing has been performed using a potentio-galvanostat. The results show that gold sputtered nanowire hybrid carbon fiber provides 65.9% better performance than bare carbon fiber cloth as super-capacitor.

  8. Plasticity of somatosensory inputs to the cochlear nucleus--implications for tinnitus.

    PubMed

    Shore, S E

    2011-11-01

    This chapter reviews evidence for functional connections of the somatosensory and auditory systems at the very lowest levels of the nervous system. Neural inputs from the dosal root and trigeminal ganglia, as well as their brain stem nuclei, cuneate, gracillis and trigeminal, terminate in the cochlear nuclei. Terminations are primarily in the shell regions surrounding the cochlear nuclei but some terminals are found in the magnocellular regions of cochlear nucleus. The effects of stimulating these inputs on multisensory integration are shown as short and long-term, both suppressive and enhancing. Evidence that these projections are glutamatergic and are altered after cochlear damage is provided in the light of probable influences on the modulation and generation of tinnitus.

  9. Plasticity of somatosensory inputs to the cochlear nucleus – implications for tinnitus

    PubMed Central

    Shore, S.E.

    2011-01-01

    This chapter reviews evidence for functional connections of the somatosensory and auditory systems at the very lowest levels of the nervous system. Neural inputs from the dosal root and trigeminal ganglia, as well as their brain stem nuclei, cuneate, gracillis and trigeminal, terminate in the cochlear nuclei. Terminations are primarily in the shell regions surrounding the cochlear nuclei but some terminals are found in the magnocellular regions of cochlear nucleus. The effects of stimulating these inputs on multisensory integration are shown as short and long-term, both suppressive and enhancing. Evidence that these projections are glutamatergic and are altered after cochlear damage is provided in the light of probable influences on the modulation and generation of tinnitus. PMID:21620940

  10. Microbial diversity drives multifunctionality in terrestrial ecosystems.

    PubMed

    Delgado-Baquerizo, Manuel; Maestre, Fernando T; Reich, Peter B; Jeffries, Thomas C; Gaitan, Juan J; Encinar, Daniel; Berdugo, Miguel; Campbell, Colin D; Singh, Brajesh K

    2016-01-28

    Despite the importance of microbial communities for ecosystem services and human welfare, the relationship between microbial diversity and multiple ecosystem functions and services (that is, multifunctionality) at the global scale has yet to be evaluated. Here we use two independent, large-scale databases with contrasting geographic coverage (from 78 global drylands and from 179 locations across Scotland, respectively), and report that soil microbial diversity positively relates to multifunctionality in terrestrial ecosystems. The direct positive effects of microbial diversity were maintained even when accounting simultaneously for multiple multifunctionality drivers (climate, soil abiotic factors and spatial predictors). Our findings provide empirical evidence that any loss in microbial diversity will likely reduce multifunctionality, negatively impacting the provision of services such as climate regulation, soil fertility and food and fibre production by terrestrial ecosystems.

  11. Advanced Multifunctional MMOD Shield: Radiation Shielding Assessment

    NASA Technical Reports Server (NTRS)

    Rojdev, Kristina; Christiansen, Eric

    2013-01-01

    Deep space missions must contend with a harsh radiation environment Impacts to crew and electronics. Need to invest in multifunctionality for spacecraft optimization. MMOD shield. Goals: Increase radiation mitigation potential. Retain overall MMOD shielding performance.

  12. Microbial diversity drives multifunctionality in terrestrial ecosystems

    PubMed Central

    Delgado-Baquerizo, Manuel; Maestre, Fernando T.; Reich, Peter B.; Jeffries, Thomas C.; Gaitan, Juan J.; Encinar, Daniel; Berdugo, Miguel; Campbell, Colin D.; Singh, Brajesh K.

    2016-01-01

    Despite the importance of microbial communities for ecosystem services and human welfare, the relationship between microbial diversity and multiple ecosystem functions and services (that is, multifunctionality) at the global scale has yet to be evaluated. Here we use two independent, large-scale databases with contrasting geographic coverage (from 78 global drylands and from 179 locations across Scotland, respectively), and report that soil microbial diversity positively relates to multifunctionality in terrestrial ecosystems. The direct positive effects of microbial diversity were maintained even when accounting simultaneously for multiple multifunctionality drivers (climate, soil abiotic factors and spatial predictors). Our findings provide empirical evidence that any loss in microbial diversity will likely reduce multifunctionality, negatively impacting the provision of services such as climate regulation, soil fertility and food and fibre production by terrestrial ecosystems. PMID:26817514

  13. Cortical Hubs Form a Module for Multisensory Integration on Top of the Hierarchy of Cortical Networks

    PubMed Central

    Zamora-López, Gorka; Zhou, Changsong; Kurths, Jürgen

    2009-01-01

    Sensory stimuli entering the nervous system follow particular paths of processing, typically separated (segregated) from the paths of other modal information. However, sensory perception, awareness and cognition emerge from the combination of information (integration). The corticocortical networks of cats and macaque monkeys display three prominent characteristics: (i) modular organisation (facilitating the segregation), (ii) abundant alternative processing paths and (iii) the presence of highly connected hubs. Here, we study in detail the organisation and potential function of the cortical hubs by graph analysis and information theoretical methods. We find that the cortical hubs form a spatially delocalised, but topologically central module with the capacity to integrate multisensory information in a collaborative manner. With this, we resolve the underlying anatomical substrate that supports the simultaneous capacity of the cortex to segregate and to integrate multisensory information. PMID:20428515

  14. Brief Cortical Deactivation Early in Life Has Long-Lasting Effects on Multisensory Behavior

    PubMed Central

    Jiang, Wan; Stein, Barry E.

    2014-01-01

    Detecting and locating environmental events are markedly enhanced by the midbrain's ability to integrate visual and auditory cues. Its capacity for multisensory integration develops in cats 1–4 months after birth but only after acquiring extensive visual–auditory experience. However, briefly deactivating specific regions of association cortex during this period induced long-term disruption of this maturational process, such that even 1 year later animals were unable to integrate visual and auditory cues to enhance their behavioral performance. The data from this animal model reveal a window of sensitivity within which association cortex mediates the encoding of cross-modal experience in the midbrain. Surprisingly, however, 3 years later, and without any additional intervention, the capacity appeared fully developed. This suggests that, although sensitivity degrades with age, the potential for acquiring or modifying multisensory integration capabilities extends well into adulthood. PMID:24849354

  15. Synaptic diversity enables temporal coding of coincident multi-sensory inputs in single neurons

    PubMed Central

    Chabrol, François P.; Arenz, Alexander; Wiechert, Martin T.; Margrie, Troy W.; DiGregorio, David A.

    2015-01-01

    The ability of the brain to rapidly process information from multiple pathways is critical for reliable execution of complex sensory-motor behaviors, yet the cellular mechanisms underlying a neuronal representation of multimodal stimuli are poorly understood. Here we explored the possibility that the physiological diversity of mossy fiber (MF) to granule cell (GC) synapses within the mouse vestibulocerebellum may contribute to the processing of coincident multisensory information at the level of individual GCs. We found that the strength and short-term dynamics of individual MF-GC synapses can act as biophysical signatures for primary vestibular, secondary vestibular and visual input pathways. The majority of GCs receive inputs from different modalities, which when co-activated, produced enhanced GC firing rates and distinct first spike latencies. Thus, pathway-specific synaptic response properties permit temporal coding of correlated multisensory input by single GCs, thereby enriching sensory representation and facilitating pattern separation. PMID:25821914

  16. Oscillatory brain activity during multisensory attention reflects activation, disinhibition, and cognitive control

    PubMed Central

    Friese, Uwe; Daume, Jonathan; Göschl, Florian; König, Peter; Wang, Peng; Engel, Andreas K.

    2016-01-01

    In this study, we used a novel multisensory attention paradigm to investigate attention-modulated cortical oscillations over a wide range of frequencies using magnetencephalography in healthy human participants. By employing a task that required the evaluation of the congruence of audio-visual stimuli, we promoted the formation of widespread cortical networks including early sensory cortices as well as regions associated with cognitive control. We found that attention led to increased high-frequency gamma-band activity and decreased lower frequency theta-, alpha-, and beta-band activity in early sensory cortex areas. Moreover, alpha-band coherence decreased in visual cortex. Frontal cortex was found to exert attentional control through increased low-frequency phase synchronisation. Crossmodal congruence modulated beta-band coherence in mid-cingulate and superior temporal cortex. Together, these results offer an integrative view on the concurrence of oscillations at different frequencies during multisensory attention. PMID:27604647

  17. Cortical hubs form a module for multisensory integration on top of the hierarchy of cortical networks.

    PubMed

    Zamora-López, Gorka; Zhou, Changsong; Kurths, Jürgen

    2010-01-01

    Sensory stimuli entering the nervous system follow particular paths of processing, typically separated (segregated) from the paths of other modal information. However, sensory perception, awareness and cognition emerge from the combination of information (integration). The corticocortical networks of cats and macaque monkeys display three prominent characteristics: (i) modular organisation (facilitating the segregation), (ii) abundant alternative processing paths and (iii) the presence of highly connected hubs. Here, we study in detail the organisation and potential function of the cortical hubs by graph analysis and information theoretical methods. We find that the cortical hubs form a spatially delocalised, but topologically central module with the capacity to integrate multisensory information in a collaborative manner. With this, we resolve the underlying anatomical substrate that supports the simultaneous capacity of the cortex to segregate and to integrate multisensory information.

  18. Audio-visual multisensory integration in superior parietal lobule revealed by human intracranial recordings.

    PubMed

    Molholm, Sophie; Sehatpour, Pejman; Mehta, Ashesh D; Shpaner, Marina; Gomez-Ramirez, Manuel; Ortigue, Stephanie; Dyke, Jonathan P; Schwartz, Theodore H; Foxe, John J

    2006-08-01

    Intracranial recordings from three human subjects provide the first direct electrophysiological evidence for audio-visual multisensory processing in the human superior parietal lobule (SPL). Auditory and visual sensory inputs project to the same highly localized region of the parietal cortex with auditory inputs arriving considerably earlier (30 ms) than visual inputs (75 ms). Multisensory integration processes in this region were assessed by comparing the response to simultaneous audio-visual stimulation with the algebraic sum of responses to the constituent auditory and visual unisensory stimulus conditions. Significant integration effects were seen with almost identical morphology across the three subjects, beginning between 120 and 160 ms. These results are discussed in the context of the role of SPL in supramodal spatial attention and sensory-motor transformations.

  19. Multisensory Part-based Representations of Objects in Human Lateral Occipital Cortex

    PubMed Central

    Erdogan, Goker; Chen, Quanjing; Garcea, Frank E.; Mahon, Bradford Z.; Jacobs, Robert A.

    2016-01-01

    The format of high-level object representations in temporal-occipital cortex is a fundamental and as yet unresolved issue. Here we use fMRI to show that human lateral occipital cortex (LOC) encodes novel 3-D objects in a multisensory and part-based format. We show that visual and haptic exploration of objects leads to similar patterns of neural activity in human LOC and that the shared variance between visually and haptically induced patterns of BOLD contrast in LOC reflects the part structure of the objects. We also show that linear classifiers trained on neural data from LOC on a subset of the objects successfully predict a novel object based on its component part structure. These data demonstrate a multisensory code for object representations in LOC that specifies the part structure of objects. PMID:26918587

  20. Temporary deafness can impair multisensory integration: a study of cochlear-implant users.

    PubMed

    Landry, Simon P; Guillemot, Jean-Paul; Champoux, François

    2013-07-01

    Previous investigations suggest that temporary deafness can have a dramatic impact on audiovisual speech processing. The aim of this study was to test whether temporary deafness disturbs other multisensory processes in adults. A nonspeech task involving an audiotactile illusion was administered to a group of normally hearing individuals and a group of individuals who had been temporarily auditorily deprived. Members of this latter group had their auditory detection thresholds restored to normal levels through the use of a cochlear implant. Control conditions revealed that auditory and tactile discrimination capabilities were identical in the two groups. However, whereas normally hearing individuals integrated auditory and tactile information, so that they experienced the audiotactile illusion, individuals who had been temporarily deprived did not. Given the basic nature of the task, failure to integrate multisensory information could not be explained by the use of the cochlear implant. Thus, the results suggest that normally anticipated audiotactile interactions are disturbed following temporary deafness.

  1. Meson multiplicity versus energy in relativistic nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

    Atwater, T. W.; Freier, P. S.

    1986-01-01

    A systematic study of meson multiplicity as a function of energy at energies up to 100 GeV/u in nucleus-nucleus collisions has been made, using cosmic-ray data in nuclear emulsion. The data are consistent with simple nucleon-nucleon superposition models. Multiplicity per interacting nucleon in AA collisions does not appear to differ significantly from pp collisions.

  2. Multifunctional Nanotherapeutic System for Advanced Prostate Cancer

    DTIC Science & Technology

    2013-10-01

    therapy for drug resistant prostate cancer cells. In addition the findings from this study can be extended to the combinatorial therapy involving...AD_________________ Award Number: W81XWH-11-1-0571 TITLE: “Multifunctional Nanotherapeutic System for Advanced Prostate Cancer ...29September2013 4. TITLE AND SUBTITLE Multifunctional Nanotherapeutic System for Advanced Prostate Cancer 5a. CONTRACT NUMBER W81XWH-11-1-0571 5b

  3. Multifunctional magnetic quantum dots for cancer theranostics.

    PubMed

    Singh, Surinder P

    2011-02-01

    The development of an innovative platform for cancer theranostics that will be capable of noninvasive imaging and treatment of cancerous tumors using biocompatible and multifunctional Fe3O4-ZnO core-shell magnetic quantum dots (M-QDs) is being explored. This multi-functional approach will facilitate deep tumor targeting using a combination of a specific cancer marker and an external magnetic field will simultaneously provide therapy that may evolve as a new paradigm in cancer theranostics.

  4. Active Structural Fibers for Multifunctional Composite Materials

    DTIC Science & Technology

    2014-05-06

    1. Lin, Y., Zhi, Z. and Sodano, 2012, “Barium Titanate and Barium Strontium Titanate Coated Carbon Fibers for Multifunctional Structural Capacitors...Multifunctional Structural Capacitors Consisting of Barium Titanate and Barium Strontium Titanate Coated Carbon Fibers, 18 th International Conference on... Strontium Titanate Coated SiC Fibers,” Electronic Materials and Applications 2011, Jan. 19 th –21 st Orlando, FL (Invited). 9. Lin, Y., Shaffer

  5. Momentum loss in proton-nucleus and nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

    Khan, Ferdous; Townsend, Lawrence W.

    1993-01-01

    An optical model description, based on multiple scattering theory, of longitudinal momentum loss in proton-nucleus and nucleus-nucleus collisions is presented. The crucial role of the imaginary component of the nucleon-nucleon transition matrix in accounting for longitudinal momentum transfer is demonstrated. Results obtained with this model are compared with Intranuclear Cascade (INC) calculations, as well as with predictions from Vlasov-Uehling-Uhlenbeck (VUU) and quantum molecular dynamics (QMD) simulations. Comparisons are also made with experimental data where available. These indicate that the present model is adequate to account for longitudinal momentum transfer in both proton-nucleus and nucleus-nucleus collisions over a wide range of energies.

  6. Alpha-Band Oscillations Reflect Altered Multisensory Processing of the McGurk Illusion in Schizophrenia.

    PubMed

    Roa Romero, Yadira; Keil, Julian; Balz, Johanna; Niedeggen, Michael; Gallinat, Jürgen; Senkowski, Daniel

    2016-01-01

    The formation of coherent multisensory percepts requires integration of stimuli across the multiple senses. Patients with schizophrenia (ScZ) often experience a loss of coherent perception and hence, they might also show dysfunctional multisensory processing. In this high-density electroencephalography study, we investigated the neural signatures of the McGurk illusion, as a phenomenon of speech-specific multisensory processing. In the McGurk illusion lip movements are paired with incongruent auditory syllables, which can induce a fused percept. In ScZ patients and healthy controls we compared neural oscillations and event-related potentials (ERPs) to congruent audiovisual speech stimuli and McGurk illusion trials, where a visual /ga/ and an auditory /pa/ was often perceived as /ka/. There were no significant group differences in illusion rates. The EEG data analysis revealed larger short latency ERPs to McGurk illusion compared with congruent trials in controls. The reversed effect pattern was found in ScZ patients, indicating an early audiovisual processing deficit. Moreover, we observed stronger suppression of medio-central alpha-band power (8-10 Hz, 550-700 ms) in response to McGurk illusion compared with control trials in the control group. Again, the reversed pattern was found in SCZ patients. Moreover, within groups, alpha-band suppression was negatively correlated with the McGurk illusion rate in ScZ patients, while the correlation tended to be positive in controls. The topography of alpha-band effects indicated an involvement of auditory and/or frontal structures. Our study suggests that short latency ERPs and long latency alpha-band oscillations reflect abnormal multisensory processing of the McGurk illusion in ScZ.

  7. A three-finger multisensory hand for dexterous space robotic tasks

    NASA Technical Reports Server (NTRS)

    Murase, Yuichi; Komada, Satoru; Uchiyama, Takashi; Machida, Kazuo; Akita, Kenzo

    1994-01-01

    The National Space Development Agency of Japan will launch ETS-7 in 1997, as a test bed for next generation space technology of RV&D and space robot. MITI has been developing a three-finger multisensory hand for complex space robotic tasks. The hand can be operated under remote control or autonomously. This paper describes the design and development of the hand and the performance of a breadboard model.

  8. An exploratory event-related potential study of multisensory integration in sensory over-responsive children.

    PubMed

    Brett-Green, Barbara A; Miller, Lucy J; Schoen, Sarah A; Nielsen, Darci M

    2010-03-19

    Children who are over-responsive to sensation have defensive and "fight or flight" reactions to ordinary levels of sensory stimulation in the environment. Based on clinical observations, sensory over-responsivity is hypothesized to reflect atypical neural integration of sensory input. To examine a possible underlying neural mechanism of the disorder, integration of simultaneous multisensory auditory and somatosensory stimulation was studied in twenty children with sensory over-responsivity (SOR) using event-related potentials (ERPs). Three types of sensory stimuli were presented and ERPs were recorded from thirty-two scalp electrodes while participants watched a silent cartoon: bilateral auditory clicks, right somatosensory median nerve electrical pulses, or both simultaneously. The paradigm was passive; no behavioral responses were required. To examine integration, responses to simultaneous multisensory auditory-somatosensory stimulation were compared to the sum of unisensory auditory plus unisensory somatosensory responses in four time-windows: (60-80 ms, 80-110 ms, 110-150 ms, and 180-220 ms). Specific midline and lateral electrode sites were examined over scalp regions where auditory-somatosensory integration was expected based on previous studies. Midline electrode sites (Fz, Cz, and Pz) showed significant integration during two time-windows: 60-80 ms and 180-220 ms. Significant integration was also found at contralateral electrode site (C3) for the time-window between 180 and 220 ms. At ipsilateral electrode sites (C4 and CP6), no significant integration was found during any of the time-windows (i.e. the multisensory ERP was not significantly different from the summed unisensory ERP). These results demonstrate that MSI can be reliably measured in children with SOR and provide evidence that multisensory auditory-somatosensory input is integrated during both early and later stages of sensory information processing, mainly over fronto-central scalp regions.

  9. The effect of ageing on multisensory integration for the control of movement timing.

    PubMed

    Elliott, Mark T; Wing, Alan M; Welchman, Andrew E

    2011-09-01

    Previously, it has been shown that synchronising actions with periodic pacing stimuli are unaffected by ageing. However, synchronisation often requires combining evidence across multiple sources of timing information. We have previously shown the brain integrates multisensory cues to achieve a best estimate of the events in time and subsequently reduces variability in synchronised movements (Elliott et al. in Eur J Neurosci 31(10):1828-1835, 2010). Yet, it is unclear if sensory integration of temporal cues in older adults is degraded and whether this leads to reduced synchronisation performance. Here, we test for age-related changes when synchronising actions to multisensory temporal cues. We compared synchronisation performance between young (N = 15, aged 18-37 years) and older adults (N = 15, aged 63-80 years) using a finger-tapping task to auditory and tactile metronomes presented unimodally and bimodally. We added temporal jitter to the auditory metronome to determine whether participants would integrate auditory and tactile signals, with reduced weighting of the auditory metronome as its reliability decreased under bimodal conditions. We found that older adults matched the performance of young adults when synchronising to an isochronous auditory or tactile metronome. When the temporal regularity of the auditory metronome was reduced, older adults' performance was degraded to a greater extent than the young adults in both unimodal and bimodal conditions. However, proportionally both groups showed similar improvements in synchronisation performance in bimodal conditions compared with the equivalent, auditory-only conditions. We conclude that while older adults become more variable in synchronising to less regular beats, they do not show any deficit in the integration of multisensory temporal cues, suggesting that using multisensory information may help mitigate any deficits in coordinating actions to complex timing cues.

  10. Multisensory speech perception in autism spectrum disorder: From phoneme to whole-word perception.

    PubMed

    Stevenson, Ryan A; Baum, Sarah H; Segers, Magali; Ferber, Susanne; Barense, Morgan D; Wallace, Mark T

    2017-03-24

    Speech perception in noisy environments is boosted when a listener can see the speaker's mouth and integrate the auditory and visual speech information. Autistic children have a diminished capacity to integrate sensory information across modalities, which contributes to core symptoms of autism, such as impairments in social communication. We investigated the abilities of autistic and typically-developing (TD) children to integrate auditory and visual speech stimuli in various signal-to-noise ratios (SNR). Measurements of both whole-word and phoneme recognition were recorded. At the level of whole-word recognition, autistic children exhibited reduced performance in both the auditory and audiovisual modalities. Importantly, autistic children showed reduced behavioral benefit from multisensory integration with whole-word recognition, specifically at low SNRs. At the level of phoneme recognition, autistic children exhibited reduced performance relative to their TD peers in auditory, visual, and audiovisual modalities. However, and in contrast to their performance at the level of whole-word recognition, both autistic and TD children showed benefits from multisensory integration for phoneme recognition. In accordance with the principle of inverse effectiveness, both groups exhibited greater benefit at low SNRs relative to high SNRs. Thus, while autistic children showed typical multisensory benefits during phoneme recognition, these benefits did not translate to typical multisensory benefit of whole-word recognition in noisy environments. We hypothesize that sensory impairments in autistic children raise the SNR threshold needed to extract meaningful information from a given sensory input, resulting in subsequent failure to exhibit behavioral benefits from additional sensory information at the level of whole-word recognition. Autism Res 2017. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

  11. The Maxillary Palp of Aedes aegypti, a Model of Multisensory Integration

    DTIC Science & Technology

    2014-01-01

    role in sexual behavior. Behav. Genet . 41, 746e753. Weiss, L.A., Dahanukar, A., Kwon, J.Y., Banerjee, D., Carlson, J.R., 2011. The molecular and...behavior concludes a series of multisensory events guiding the mosquito to its host from a distance. The antennae and maxillary palps play a major role in...model for exploration of the neu- romolecular networks underlying chemo- and mechanosensation. In this study, we surveyed the expressed genetic

  12. Hemodynamic responses in human multisensory and auditory association cortex to purely visual stimulation

    PubMed Central

    Meyer, Martin; Baumann, Simon; Marchina, Sarah; Jancke, Lutz

    2007-01-01

    Background Recent findings of a tight coupling between visual and auditory association cortices during multisensory perception in monkeys and humans raise the question whether consistent paired presentation of simple visual and auditory stimuli prompts conditioned responses in unimodal auditory regions or multimodal association cortex once visual stimuli are presented in isolation in a post-conditioning run. To address this issue fifteen healthy participants partook in a "silent" sparse temporal event-related fMRI study. In the first (visual control) habituation phase they were presented with briefly red flashing visual stimuli. In the second (auditory control) habituation phase they heard brief telephone ringing. In the third (conditioning) phase we coincidently presented the visual stimulus (CS) paired with the auditory stimulus (UCS). In the fourth phase participants either viewed flashes paired with the auditory stimulus (maintenance, CS-) or viewed the visual stimulus in isolation (extinction, CS+) according to a 5:10 partial reinforcement schedule. The participants had no other task than attending to the stimuli and indicating the end of each trial by pressing a button. Results During unpaired visual presentations (preceding and following the paired presentation) we observed significant brain responses beyond primary visual cortex in the bilateral posterior auditory association cortex (planum temporale, planum parietale) and in the right superior temporal sulcus whereas the primary auditory regions were not involved. By contrast, the activity in auditory core regions was markedly larger when participants were presented with auditory stimuli. Conclusion These results demonstrate involvement of multisensory and auditory association areas in perception of unimodal visual stimulation which may reflect the instantaneous forming of multisensory associations and cannot be attributed to sensation of an auditory event. More importantly, we are able to show that brain

  13. Neuro-oscillatory phase alignment drives speeded multisensory response times: an electro-corticographic investigation.

    PubMed

    Mercier, Manuel R; Molholm, Sophie; Fiebelkorn, Ian C; Butler, John S; Schwartz, Theodore H; Foxe, John J

    2015-06-03

    Even simple tasks rely on information exchange between functionally distinct and often relatively distant neuronal ensembles. Considerable work indicates oscillatory synchronization through phase alignment is a major agent of inter-regional communication. In the brain, different oscillatory phases correspond to low- and high-excitability states. Optimally aligned phases (or high-excitability states) promote inter-regional communication. Studies have also shown that sensory stimulation can modulate or reset the phase of ongoing cortical oscillations. For example, auditory stimuli can reset the phase of oscillations in visual cortex, influencing processing of a simultaneous visual stimulus. Such cross-regional phase reset represents a candidate mechanism for aligning oscillatory phase for inter-regional communication. Here, we explored the role of local and inter-regional phase alignment in driving a well established behavioral correlate of multisensory integration: the redundant target effect (RTE), which refers to the fact that responses to multisensory inputs are substantially faster than to unisensory stimuli. In a speeded detection task, human epileptic patients (N = 3) responded to unisensory (auditory or visual) and multisensory (audiovisual) stimuli with a button press, while electrocorticography was recorded over auditory and motor regions. Visual stimulation significantly modulated auditory activity via phase reset in the delta and theta bands. During the period between stimulation and subsequent motor response, transient synchronization between auditory and motor regions was observed. Phase synchrony to multisensory inputs was faster than to unisensory stimulation. This sensorimotor phase alignment correlated with behavior such that stronger synchrony was associated with faster responses, linking the commonly observed RTE with phase alignment across a sensorimotor network.

  14. Uni- and multisensory brain areas are synchronised across spectators when watching unedited dance recordings

    PubMed Central

    Jola, Corinne; McAleer, Phil; Grosbras, Marie-Hélène; Love, Scott A.; Morison, Gordon; Pollick, Frank E.

    2013-01-01

    The superior temporal sulcus (STS) and gyrus (STG) are commonly identified to be functionally relevant for multisensory integration of audiovisual (AV) stimuli. However, most neuroimaging studies on AV integration used stimuli of short duration in explicit evaluative tasks. Importantly though, many of our AV experiences are of a long duration and ambiguous. It is unclear if the enhanced activity in audio, visual, and AV brain areas would also be synchronised over time across subjects when they are exposed to such multisensory stimuli. We used intersubject correlation to investigate which brain areas are synchronised across novices for uni- and multisensory versions of a 6-min 26-s recording of an unfamiliar, unedited Indian dance recording (Bharatanatyam). In Bharatanatyam, music and dance are choreographed together in a highly intermodal-dependent manner. Activity in the middle and posterior STG was significantly correlated between subjects and showed also significant enhancement for AV integration when the functional magnetic resonance signals were contrasted against each other using a general linear model conjunction analysis. These results extend previous studies by showing an intermediate step of synchronisation for novices: while there was a consensus across subjects' brain activity in areas relevant for unisensory processing and AV integration of related audio and visual stimuli, we found no evidence for synchronisation of higher level cognitive processes, suggesting these were idiosyncratic. PMID:24349687

  15. Multisensory integration of colors and scents: insights from bees and flowers.

    PubMed

    Leonard, Anne S; Masek, Pavel

    2014-06-01

    Karl von Frisch's studies of bees' color vision and chemical senses opened a window into the perceptual world of a species other than our own. A century of subsequent research on bees' visual and olfactory systems has developed along two productive but independent trajectories, leaving the questions of how and why bees use these two senses in concert largely unexplored. Given current interest in multimodal communication and recently discovered interplay between olfaction and vision in humans and Drosophila, understanding multisensory integration in bees is an opportunity to advance knowledge across fields. Using a classic ethological framework, we formulate proximate and ultimate perspectives on bees' use of multisensory stimuli. We discuss interactions between scent and color in the context of bee cognition and perception, focusing on mechanistic and functional approaches, and we highlight opportunities to further explore the development and evolution of multisensory integration. We argue that although the visual and olfactory worlds of bees are perhaps the best-studied of any non-human species, research focusing on the interactions between these two sensory modalities is vitally needed.

  16. Multi-Sensory and Sensorimotor Foundation of Bodily Self-Consciousness – An Interdisciplinary Approach

    PubMed Central

    Ionta, Silvio; Gassert, Roger; Blanke, Olaf

    2011-01-01

    Scientific investigations on the nature of the self have so far focused on high-level mechanisms. Recent evidence, however, suggests that low-level bottom-up mechanisms of multi-sensory integration play a fundamental role in encoding specific components of bodily self-consciousness, such as self-location and first-person perspective (Blanke and Metzinger, 2009). Self-location and first-person perspective are abnormal in neurological patients suffering from out-of-body experiences (Blanke et al., 2004), and can be manipulated experimentally in healthy subjects by imposing multi-sensory conflicts (Lenggenhager et al., 2009). Activity of the temporo-parietal junction (TPJ) reflects experimentally induced changes in self-location and first-person perspective (Ionta et al., 2011), and dysfunctions in TPJ are causally associated with out-of-body experiences (Blanke et al., 2002). We argue that TPJ is one of the key areas for multi-sensory integration of bodily self-consciousness, that its levels of activity reflect the experience of the conscious “I” as embodied and localized within bodily space, and that these mechanisms can be systematically investigated using state of the art technologies such as robotics, virtual reality, and non-invasive neuroimaging. PMID:22207860

  17. Recurrent network for multisensory integration-identification of common sources of audiovisual stimuli.

    PubMed

    Yamashita, Itsuki; Katahira, Kentaro; Igarashi, Yasuhiko; Okanoya, Kazuo; Okada, Masato

    2013-01-01

    We perceive our surrounding environment by using different sense organs. However, it is not clear how the brain estimates information from our surroundings from the multisensory stimuli it receives. While Bayesian inference provides a normative account of the computational principle at work in the brain, it does not provide information on how the nervous system actually implements the computation. To provide an insight into how the neural dynamics are related to multisensory integration, we constructed a recurrent network model that can implement computations related to multisensory integration. Our model not only extracts information from noisy neural activity patterns, it also estimates a causal structure; i.e., it can infer whether the different stimuli came from the same source or different sources. We show that our model can reproduce the results of psychophysical experiments on spatial unity and localization bias which indicate that a shift occurs in the perceived position of a stimulus through the effect of another simultaneous stimulus. The experimental data have been reproduced in previous studies using Bayesian models. By comparing the Bayesian model and our neural network model, we investigated how the Bayesian prior is represented in neural circuits.

  18. Testing sensory and multisensory function in children with autism spectrum disorder.

    PubMed

    Baum, Sarah H; Stevenson, Ryan A; Wallace, Mark T

    2015-04-22

    In addition to impairments in social communication and the presence of restricted interests and repetitive behaviors, deficits in sensory processing are now recognized as a core symptom in autism spectrum disorder (ASD). Our ability to perceive and interact with the external world is rooted in sensory processing. For example, listening to a conversation entails processing the auditory cues coming from the speaker (speech content, prosody, syntax) as well as the associated visual information (facial expressions, gestures). Collectively, the "integration" of these multisensory (i.e., combined audiovisual) pieces of information results in better comprehension. Such multisensory integration has been shown to be strongly dependent upon the temporal relationship of the paired stimuli. Thus, stimuli that occur in close temporal proximity are highly likely to result in behavioral and perceptual benefits--gains believed to be reflective of the perceptual system's judgment of the likelihood that these two stimuli came from the same source. Changes in this temporal integration are expected to strongly alter perceptual processes, and are likely to diminish the ability to accurately perceive and interact with our world. Here, a battery of tasks designed to characterize various aspects of sensory and multisensory temporal processing in children with ASD is described. In addition to its utility in autism, this battery has great potential for characterizing changes in sensory function in other clinical populations, as well as being used to examine changes in these processes across the lifespan.

  19. Impairments of multisensory integration and cross-sensory learning as pathways to dyslexia.

    PubMed

    Hahn, Noemi; Foxe, John J; Molholm, Sophie

    2014-11-01

    Two sensory systems are intrinsic to learning to read. Written words enter the brain through the visual system and associated sounds through the auditory system. The task before the beginning reader is quite basic. She must learn correspondences between orthographic tokens and phonemic utterances, and she must do this to the point that there is seamless automatic 'connection' between these sensorially distinct units of language. It is self-evident then that learning to read requires formation of cross-sensory associations to the point that deeply encoded multisensory representations are attained. While the majority of individuals manage this task to a high degree of expertise, some struggle to attain even rudimentary capabilities. Why do dyslexic individuals, who learn well in myriad other domains, fail at this particular task? Here, we examine the literature as it pertains to multisensory processing in dyslexia. We find substantial support for multisensory deficits in dyslexia, and make the case that to fully understand its neurological basis, it will be necessary to thoroughly probe the integrity of auditory-visual integration mechanisms.

  20. Natural asynchronies in audiovisual communication signals regulate neuronal multisensory interactions in voice-sensitive cortex

    PubMed Central

    Perrodin, Catherine; Kayser, Christoph; Logothetis, Nikos K.; Petkov, Christopher I.

    2015-01-01

    When social animals communicate, the onset of informative content in one modality varies considerably relative to the other, such as when visual orofacial movements precede a vocalization. These naturally occurring asynchronies do not disrupt intelligibility or perceptual coherence. However, they occur on time scales where they likely affect integrative neuronal activity in ways that have remained unclear, especially for hierarchically downstream regions in which neurons exhibit temporally imprecise but highly selective responses to communication signals. To address this, we exploited naturally occurring face- and voice-onset asynchronies in primate vocalizations. Using these as stimuli we recorded cortical oscillations and neuronal spiking responses from functional MRI (fMRI)-localized voice-sensitive cortex in the anterior temporal lobe of macaques. We show that the onset of the visual face stimulus resets the phase of low-frequency oscillations, and that the face–voice asynchrony affects the prominence of two key types of neuronal multisensory responses: enhancement or suppression. Our findings show a three-way association between temporal delays in audiovisual communication signals, phase-resetting of ongoing oscillations, and the sign of multisensory responses. The results reveal how natural onset asynchronies in cross-sensory inputs regulate network oscillations and neuronal excitability in the voice-sensitive cortex of macaques, a suggested animal model for human voice areas. These findings also advance predictions on the impact of multisensory input on neuronal processes in face areas and other brain regions. PMID:25535356

  1. Multisensory Interactions Influence Neuronal Spike Train Dynamics in the Posterior Parietal Cortex

    PubMed Central

    VanGilder, Paul; Shi, Ying; Apker, Gregory; Dyson, Keith; Buneo, Christopher A.

    2016-01-01

    Although significant progress has been made in understanding multisensory interactions at the behavioral level, their underlying neural mechanisms remain relatively poorly understood in cortical areas, particularly during the control of action. In recent experiments where animals reached to and actively maintained their arm position at multiple spatial locations while receiving either proprioceptive or visual-proprioceptive position feedback, multisensory interactions were shown to be associated with reduced spiking (i.e. subadditivity) as well as reduced intra-trial and across-trial spiking variability in the superior parietal lobule (SPL). To further explore the nature of such interaction-induced changes in spiking variability we quantified the spike train dynamics of 231 of these neurons. Neurons were classified as Poisson, bursty, refractory, or oscillatory (in the 13–30 Hz “beta-band”) based on their spike train power spectra and autocorrelograms. No neurons were classified as Poisson-like in either the proprioceptive or visual-proprioceptive conditions. Instead, oscillatory spiking was most commonly observed with many neurons exhibiting these oscillations under only one set of feedback conditions. The results suggest that the SPL may belong to a putative beta-synchronized network for arm position maintenance and that position estimation may be subserved by different subsets of neurons within this network depending on available sensory information. In addition, the nature of the observed spiking variability suggests that models of multisensory interactions in the SPL should account for both Poisson-like and non-Poisson variability. PMID:28033334

  2. Functional specializations of the ventral intraparietal area for multisensory heading discrimination.

    PubMed

    Chen, Aihua; Deangelis, Gregory C; Angelaki, Dora E

    2013-02-20

    The ventral intraparietal area (VIP) of the macaque brain is a multimodal cortical region with directionally selective responses to visual and vestibular stimuli. To explore how these signals contribute to self-motion perception, neural activity in VIP was monitored while macaques performed a fine heading discrimination task based on vestibular, visual, or multisensory cues. For neurons with congruent visual and vestibular heading tuning, discrimination thresholds improved during multisensory stimulation, suggesting that VIP (like the medial superior temporal area; MSTd) may contribute to the improved perceptual discrimination seen during cue combination. Unlike MSTd, however, few VIP neurons showed opposite visual/vestibular tuning over the range of headings relevant to behavior, and those few cells showed reduced sensitivity under cue combination. Our data suggest that the heading tuning of some VIP neurons may be locally remodeled to increase the proportion of cells with congruent tuning over the behaviorally relevant stimulus range. VIP neurons also showed much stronger trial-by-trial correlations with perceptual decisions (choice probabilities; CPs) than MSTd neurons. While this may suggest that VIP neurons are more strongly linked to heading perception, we also find that correlated noise is much stronger among pairs of VIP neurons, with noise correlations averaging 0.14 in VIP as compared with 0.04 in MSTd. Thus, the large CPs in VIP could be a consequence of strong interneuronal correlations. Together, our findings suggest that VIP neurons show specializations that may make them well equipped to play a role in multisensory integration for heading perception.

  3. Multisensory Integration and Calibration in Children and Adults with and without Sensory and Motor Disabilities.

    PubMed

    Gori, Monica

    2015-01-01

    During the first years of life, sensory modalities communicate with each other. This process is fundamental for the development of unisensory and multisensory skills. The absence of one sensory input impacts on the development of other modalities. Since 2008 we have studied these aspects and developed our cross-sensory calibration theory. This theory emerged from the observation that children start to integrate multisensory information (such as vision and touch) only after 8-10 years of age. Before this age the more accurate sense teaches (calibrates) the others; when one calibrating modality is missing, the other modalities result impaired. Children with visual disability have problems in understanding the haptic or auditory perception of space and children with motor disabilities have problems in understanding the visual dimension of objects. This review presents our recent studies on multisensory integration and cross-sensory calibration in children and adults with and without sensory and motor disabilities. The goal of this review is to show the importance of interaction between sensory systems during the early period of life in order to correct perceptual development to occur.

  4. Uni- and multisensory brain areas are synchronised across spectators when watching unedited dance recordings.

    PubMed

    Jola, Corinne; McAleer, Phil; Grosbras, Marie-Hélène; Love, Scott A; Morison, Gordon; Pollick, Frank E

    2013-01-01

    The superior temporal sulcus (STS) and gyrus (STG) are commonly identified to be functionally relevant for multisensory integration of audiovisual (AV) stimuli. However, most neuroimaging studies on AV integration used stimuli of short duration in explicit evaluative tasks. Importantly though, many of our AV experiences are of a long duration and ambiguous. It is unclear if the enhanced activity in audio, visual, and AV brain areas would also be synchronised over time across subjects when they are exposed to such multisensory stimuli. We used intersubject correlation to investigate which brain areas are synchronised across novices for uni- and multisensory versions of a 6-min 26-s recording of an unfamiliar, unedited Indian dance recording (Bharatanatyam). In Bharatanatyam, music and dance are choreographed together in a highly intermodal-dependent manner. Activity in the middle and posterior STG was significantly correlated between subjects and showed also significant enhancement for AV integration when the functional magnetic resonance signals were contrasted against each other using a general linear model conjunction analysis. These results extend previous studies by showing an intermediate step of synchronisation for novices: while there was a consensus across subjects' brain activity in areas relevant for unisensory processing and AV integration of related audio and visual stimuli, we found no evidence for synchronisation of higher level cognitive processes, suggesting these were idiosyncratic.

  5. Multisensory representation of the space near the hand: from perception to action and interindividual interactions.

    PubMed

    Brozzoli, Claudio; Ehrsson, H Henrik; Farnè, Alessandro

    2014-04-01

    When interacting with objects and other people, the brain needs to locate our limbs and the relevant visual information surrounding them. Studies on monkeys showed that information from different sensory modalities converge at the single cell level within a set of interconnected multisensory frontoparietal areas. It is largely accepted that this network allows for multisensory processing of the space surrounding the body (peripersonal space), whose function has been linked to the sensory guidance of appetitive and defensive movements, and localization of the limbs in space. In the current review, we consider multidisciplinary findings about the processing of the space near the hands in humans and offer a convergent view of its functions and underlying neural mechanisms. We will suggest that evolution has provided the brain with a clever tool for representing visual information around the hand, which takes the hand itself as a reference for the coding of surrounding visual space. We will contend that the hand-centered representation of space, known as perihand space, is a multisensory-motor interface that allows interaction with the objects and other persons around us.

  6. Auditory projections to extrastriate visual cortex: connectional basis for multisensory processing in 'unimodal' visual neurons.

    PubMed

    Clemo, H Ruth; Sharma, Giriraj K; Allman, Brian L; Meredith, M Alex

    2008-10-01

    Neurophysiological studies have recently documented multisensory properties in 'unimodal' visual neurons of the cat posterolateral lateral suprasylvian (PLLS) cortex, a retinotopically organized area involved in visual motion processing. In this extrastriate visual area, a region has been identified where both visual and auditory stimuli were independently effective in activating neurons (bimodal zone), as well as a second region where visually-evoked activity was significantly facilitated by concurrent auditory stimulation but was unaffected by auditory stimulation alone (subthreshold multisensory region). Given their different distributions, the possible corticocortical connectivity underlying these distinct forms of crossmodal convergence was examined using biotinylated dextran amine (BDA) tracer methods in 21 adult cats. The auditory cortical areas examined included the anterior auditory field (AAF), primary auditory cortex (AI), dorsal zone (DZ), secondary auditory cortex (AII), field of the rostral suprasylvian sulcus (FRS), field anterior ectosylvian sulcus (FAES) and the posterior auditory field (PAF). Of these regions, the DZ, AI, AII, and FAES were found to project to the both the bimodal zone and the subthreshold region of the PLLS. This convergence of crossmodal inputs to the PLLS suggests not only that complex auditory information has access to this region but also that these connections provide the substrate for the different forms (bimodal versus subthreshold) of multisensory processing which may facilitate its functional role in visual motion processing.

  7. Natural asynchronies in audiovisual communication signals regulate neuronal multisensory interactions in voice-sensitive cortex.

    PubMed

    Perrodin, Catherine; Kayser, Christoph; Logothetis, Nikos K; Petkov, Christopher I

    2015-01-06

    When social animals communicate, the onset of informative content in one modality varies considerably relative to the other, such as when visual orofacial movements precede a vocalization. These naturally occurring asynchronies do not disrupt intelligibility or perceptual coherence. However, they occur on time scales where they likely affect integrative neuronal activity in ways that have remained unclear, especially for hierarchically downstream regions in which neurons exhibit temporally imprecise but highly selective responses to communication signals. To address this, we exploited naturally occurring face- and voice-onset asynchronies in primate vocalizations. Using these as stimuli we recorded cortical oscillations and neuronal spiking responses from functional MRI (fMRI)-localized voice-sensitive cortex in the anterior temporal lobe of macaques. We show that the onset of the visual face stimulus resets the phase of low-frequency oscillations, and that the face-voice asynchrony affects the prominence of two key types of neuronal multisensory responses: enhancement or suppression. Our findings show a three-way association between temporal delays in audiovisual communication signals, phase-resetting of ongoing oscillations, and the sign of multisensory responses. The results reveal how natural onset asynchronies in cross-sensory inputs regulate network oscillations and neuronal excitability in the voice-sensitive cortex of macaques, a suggested animal model for human voice areas. These findings also advance predictions on the impact of multisensory input on neuronal processes in face areas and other brain regions.

  8. Lost in space: multisensory conflict yields adaptation in spatial representations across frames of reference.

    PubMed

    Lohmann, Johannes; Butz, Martin V

    2017-03-27

    According to embodied cognition, bodily interactions with our environment shape the perception and representation of our body and the surrounding space, that is, peripersonal space. To investigate the adaptive nature of these spatial representations, we introduced a multisensory conflict between vision and proprioception in an immersive virtual reality. During individual bimanual interaction trials, we gradually shifted the visual hand representation. As a result, participants unknowingly shifted their actual hands to compensate for the visual shift. We then measured the adaptation to the invoked multisensory conflict by means of a self-localization and an external localization task. While effects of the conflict were observed in both tasks, the effects systematically interacted with the type of localization task and the available visual information while performing the localization task (i.e., the visibility of the virtual hands). The results imply that the localization of one's own hands is based on a multisensory integration process, which is modulated by the saliency of the currently most relevant sensory modality and the involved frame of reference. Moreover, the results suggest that our brain strives for consistency between its body and spatial estimates, thereby adapting multiple, related frames of reference, and the spatial estimates within, due to a sensory conflict in one of them.

  9. Neural Substrates of Reliability-Weighted Visual-Tactile Multisensory Integration

    PubMed Central

    Beauchamp, Michael S.; Pasalar, Siavash; Ro, Tony

    2010-01-01

    As sensory systems deteriorate in aging or disease, the brain must relearn the appropriate weights to assign each modality during multisensory integration. Using blood-oxygen level dependent functional magnetic resonance imaging of human subjects, we tested a model for the neural mechanisms of sensory weighting, termed “weighted connections.” This model holds that the connection weights between early and late areas vary depending on the reliability of the modality, independent of the level of early sensory cortex activity. When subjects detected viewed and felt touches to the hand, a network of brain areas was active, including visual areas in lateral occipital cortex, somatosensory areas in inferior parietal lobe, and multisensory areas in the intraparietal sulcus (IPS). In agreement with the weighted connection model, the connection weight measured with structural equation modeling between somatosensory cortex and IPS increased for somatosensory-reliable stimuli, and the connection weight between visual cortex and IPS increased for visual-reliable stimuli. This double dissociation of connection strengths was similar to the pattern of behavioral responses during incongruent multisensory stimulation, suggesting that weighted connections may be a neural mechanism for behavioral reliability weighting. PMID:20631844

  10. The effect of early visual deprivation on the neural bases of multisensory processing.

    PubMed

    Guerreiro, Maria J S; Putzar, Lisa; Röder, Brigitte

    2015-06-01

    Developmental vision is deemed to be necessary for the maturation of multisensory cortical circuits. Thus far, this has only been investigated in animal studies, which have shown that congenital visual deprivation markedly reduces the capability of neurons to integrate cross-modal inputs. The present study investigated the effect of transient congenital visual deprivation on the neural mechanisms of multisensory processing in humans. We used functional magnetic resonance imaging to compare responses of visual and auditory cortical areas to visual, auditory and audio-visual stimulation in cataract-reversal patients and normally sighted controls. The results showed that cataract-reversal patients, unlike normally sighted controls, did not exhibit multisensory integration in auditory areas. Furthermore, cataract-reversal patients, but not normally sighted controls, exhibited lower visual cortical processing within visual cortex during audio-visual stimulation than during visual stimulation. These results indicate that congenital visual deprivation affects the capability of cortical areas to integrate cross-modal inputs in humans, possibly because visual processing is suppressed during cross-modal stimulation. Arguably, the lack of vision in the first months after birth may result in a reorganization of visual cortex, including the suppression of noisy visual input from the deprived retina in order to reduce interference during auditory processing.

  11. The sense of body ownership relaxes temporal constraints for multisensory integration

    PubMed Central

    Maselli, Antonella; Kilteni, Konstantina; López-Moliner, Joan; Slater, Mel

    2016-01-01

    Experimental work on body ownership illusions showed how simple multisensory manipulation can generate the illusory experience of an artificial limb as being part of the own-body. This work highlighted how own-body perception relies on a plastic brain representation emerging from multisensory integration. The flexibility of this representation is reflected in the short-term modulations of physiological states and perceptual processing observed during these illusions. Here, we explore the impact of ownership illusions on the temporal dimension of multisensory integration. We show that, during the illusion, the temporal window for integrating touch on the physical body with touch seen on a virtual body representation, increases with respect to integration with visual events seen close but separated from the virtual body. We show that this effect is mediated by the ownership illusion. Crucially, the temporal window for visuotactile integration was positively correlated with participants’ scores rating the illusory experience of owning the virtual body and touching the object seen in contact with it. Our results corroborate the recently proposed causal inference mechanism for illusory body ownership. As a novelty, they show that the ensuing illusory causal binding between stimuli from the real and fake body relaxes constraints for the integration of bodily signals. PMID:27485049

  12. Impairments of Multisensory Integration and Cross-Sensory Learning as Pathways to Dyslexia

    PubMed Central

    Hahn, Noemi; Foxe, John J.; Molholm, Sophie

    2014-01-01

    Two sensory systems are intrinsic to learning to read. Written words enter the brain through the visual system and associated sounds through the auditory system. The task before the beginning reader is quite basic. She must learn correspondences between orthographic tokens and phonemic utterances, and she must do this to the point that there is seamless automatic ‘connection’ between these sensorially distinct units of language. It is self-evident then that learning to read requires formation of cross-sensory associations to the point that deeply encoded multisensory representations are attained. While the majority of individuals manage this task to a high degree of expertise, some struggle to attain even rudimentary capabilities. Why do dyslexic individuals, who learn well in myriad other domains, fail at this particular task? Here, we examine the literature as it pertains to multisensory processing in dyslexia. We find substantial support for multisensory deficits in dyslexia, and make the case that to fully understand its neurological basis, it will be necessary to thoroughly probe the integrity of auditory-visual integration mechanisms. PMID:25265514

  13. The intercalatus nucleus of Staderini.

    PubMed

    Cascella, Marco

    2016-01-01

    Rutilio Staderini was one of the leading Italian anatomists of the twentieth century, together with some scientists, such as Giulio Chiarugi, Giovanni Vitali, and others. He was also a member of a new generation of anatomists. They had continued the tradition of the most famous Italian scientists, which started from the Renaissance up until the nineteenth century. Although he carried out important studies of neuroanatomy and comparative anatomy, as well as embryology, his name is rarely remembered by most medical historians. His name is linked to the nucleus he discovered: the Staderini nucleus or intercalated nucleus, a collection of nerve cells in the medulla oblongata located lateral to the hypoglossal nucleus. This article focuses on the biography of the neuroanatomist as well as the nucleus that carries his name and his other research, especially on comparative anatomy and embryology.

  14. Biochemistry and biology of the inducible multifunctional transcription factor TFII-I.

    PubMed

    Roy, A L

    2001-08-22

    An animal cell has the capability to respond to a variety of external signals through cell surface receptors. The response is usually manifested in terms of altered gene expression in the nucleus. Thus, in modern molecular and cell biology, it has become important to understand how the communication between extracellular signals and nuclear gene transcription is achieved. Originally discovered as a basal factor required for initiator-dependent transcription in vitro, recent evidence suggests that TFII-I is also an inducible multifunctional transcription factor that is activated in response to a variety of extracellular signals and translocates to the nucleus to turn on signal-induced genes. Here I review the biochemical and biological properties of TFII-I and related proteins in nuclear gene transcription, signal transduction and genetic disorders.

  15. Compensatory Recovery after Multisensory Stimulation in Hemianopic Patients: Behavioral and Neurophysiological Components

    PubMed Central

    Grasso, Paolo A.; Làdavas, Elisabetta; Bertini, Caterina

    2016-01-01

    Lateralized post-chiasmatic lesions of the primary visual pathway result in loss of visual perception in the field retinotopically corresponding to the damaged cortical area. However, patients with visual field defects have shown enhanced detection and localization of multisensory audio-visual pairs presented in the blind field. This preserved multisensory integrative ability (i.e., crossmodal blindsight) seems to be subserved by the spared retino-colliculo-dorsal pathway. According to this view, audio-visual integrative mechanisms could be used to increase the functionality of the spared circuit and, as a consequence, might represent an important tool for the rehabilitation of visual field defects. The present study tested this hypothesis, investigating whether exposure to systematic multisensory audio-visual stimulation could induce long-lasting improvements in the visual performance of patients with visual field defects. A group of 10 patients with chronic visual field defects were exposed to audio-visual training for 4 h daily, over a period of 2 weeks. Behavioral, oculomotor and electroencephalography (EEG) measures were recorded during several visual tasks before and after audio-visual training. After audio-visual training, improvements in visual search abilities, visual detection, self-perceived disability in daily life activities and oculomotor parameters were found, suggesting the implementation of more effective visual exploration strategies. At the electrophysiological level, after training, patients showed a significant reduction of the P3 amplitude in response to stimuli presented in the intact field, reflecting a reduction in attentional resources allocated to the intact field, which might co-occur with a shift of spatial attention towards the blind field. More interestingly, both the behavioral improvements and the electrophysiological changes observed after training were found to be stable at a follow-up session (on average, 8 months after training

  16. Compensatory Recovery after Multisensory Stimulation in Hemianopic Patients: Behavioral and Neurophysiological Components.

    PubMed

    Grasso, Paolo A; Làdavas, Elisabetta; Bertini, Caterina

    2016-01-01

    Lateralized post-chiasmatic lesions of the primary visual pathway result in loss of visual perception in the field retinotopically corresponding to the damaged cortical area. However, patients with visual field defects have shown enhanced detection and localization of multisensory audio-visual pairs presented in the blind field. This preserved multisensory integrative ability (i.e., crossmodal blindsight) seems to be subserved by the spared retino-colliculo-dorsal pathway. According to this view, audio-visual integrative mechanisms could be used to increase the functionality of the spared circuit and, as a consequence, might represent an important tool for the rehabilitation of visual field defects. The present study tested this hypothesis, investigating whether exposure to systematic multisensory audio-visual stimulation could induce long-lasting improvements in the visual performance of patients with visual field defects. A group of 10 patients with chronic visual field defects were exposed to audio-visual training for 4 h daily, over a period of 2 weeks. Behavioral, oculomotor and electroencephalography (EEG) measures were recorded during several visual tasks before and after audio-visual training. After audio-visual training, improvements in visual search abilities, visual detection, self-perceived disability in daily life activities and oculomotor parameters were found, suggesting the implementation of more effective visual exploration strategies. At the electrophysiological level, after training, patients showed a significant reduction of the P3 amplitude in response to stimuli presented in the intact field, reflecting a reduction in attentional resources allocated to the intact field, which might co-occur with a shift of spatial attention towards the blind field. More interestingly, both the behavioral improvements and the electrophysiological changes observed after training were found to be stable at a follow-up session (on average, 8 months after training

  17. Multifunctional self-assembled monolayers

    SciTech Connect

    Zawodzinski, T.; Bar, G.; Rubin, S.; Uribe, F.; Ferrais, J.

    1996-06-01

    This is the final report of at three year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The specific goals of this research project were threefold: to develop multifunctional self-assembled monolayers, to understand the role of monolayer structure on the functioning of such systems, and to apply this knowledge to the development of electrochemical enzyme sensors. An array of molecules that can be used to attach electrochemically active biomolecules to gold surfaces has been synthesized. Several members of a class of electroactive compounds have been characterized and the factors controlling surface modification are beginning to be characterized. Enzymes have been attached to self-assembled molecules arranged on the gold surface, a critical step toward the ultimate goal of this project. Several alternative enzyme attachment strategies to achieve robust enzyme- modified surfaces have been explored. Several means of juxtaposing enzymes and mediators, electroactive compounds through which the enzyme can exchange electrons with the electrode surface, have also been investigated. Finally, the development of sensitive biosensors based on films loaded with nanoscale-supported gold particles that have surface modified with the self-assembled enzyme and mediator have been explored.

  18. Multifunctional nanorods for gene delivery

    NASA Astrophysics Data System (ADS)

    Salem, Aliasger K.; Searson, Peter C.; Leong, Kam W.

    2003-10-01

    The goal of gene therapy is to introduce foreign genes into somatic cells to supplement defective genes or provide additional biological functions, and can be achieved using either viral or synthetic non-viral delivery systems. Compared with viral vectors, synthetic gene-delivery systems, such as liposomes and polymers, offer several advantages including ease of production and reduced risk of cytotoxicity and immunogenicity, but their use has been limited by the relatively low transfection efficiency. This problem mainly stems from the difficulty in controlling their properties at the nanoscale. Synthetic inorganic gene carriers have received limited attention in the gene-therapy community, the only notable example being gold nanoparticles with surface-immobilized DNA applied to intradermal genetic immunization by particle bombardment. Here we present a non-viral gene-delivery system based on multisegment bimetallic nanorods that can simultaneously bind compacted DNA plasmids and targeting ligands in a spatially defined manner. This approach allows precise control of composition, size and multifunctionality of the gene-delivery system. Transfection experiments performed in vitro and in vivo provide promising results that suggest potential in genetic vaccination applications.

  19. Disintegration of Multisensory Signals from the Real Hand Reduces Default Limb Self-Attribution: An fMRI Study

    PubMed Central

    Guterstam, Arvid; Brozzoli, Claudio; Ehrsson, H. Henrik

    2013-01-01

    The perception of our limbs in space is built upon the integration of visual, tactile, and proprioceptive signals. Accumulating evidence suggests that these signals are combined in areas of premotor, parietal, and cerebellar cortices. However, it remains to be determined whether neuronal populations in these areas integrate hand signals according to basic temporal and spatial congruence principles of multisensory integration. Here, we developed a setup based on advanced 3D video technology that allowed us to manipulate the spatiotemporal relationships of visuotactile (VT) stimuli delivered on a healthy human participant's real hand during fMRI and investigate the ensuing neural and perceptual correlates. Our experiments revealed two novel findings. First, we found responses in premotor, parietal, and cerebellar regions that were dependent upon the spatial and temporal congruence of VT stimuli. This multisensory integration effect required a simultaneous match between the seen and felt postures of the hand, which suggests that congruent visuoproprioceptive signals from the upper limb are essential for successful VT integration. Second, we observed that multisensory conflicts significantly disrupted the default feeling of ownership of the seen real limb, as indexed by complementary subjective, psychophysiological, and BOLD measures. The degree to which self-attribution was impaired could be predicted from the attenuation of neural responses in key multisensory areas. These results elucidate the neural bases of the integration of multisensory hand signals according to basic spatiotemporal principles and demonstrate that the disintegration of these signals leads to “disownership” of the seen real hand. PMID:23946393

  20. Learning multisensory representations for auditory-visual transfer of sequence category knowledge: a probabilistic language of thought approach.

    PubMed

    Yildirim, Ilker; Jacobs, Robert A

    2015-06-01

    If a person is trained to recognize or categorize objects or events using one sensory modality, the person can often recognize or categorize those same (or similar) objects and events via a novel modality. This phenomenon is an instance of cross-modal transfer of knowledge. Here, we study the Multisensory Hypothesis which states that people extract the intrinsic, modality-independent properties of objects and events, and represent these properties in multisensory representations. These representations underlie cross-modal transfer of knowledge. We conducted an experiment evaluating whether people transfer sequence category knowledge across auditory and visual domains. Our experimental data clearly indicate that we do. We also developed a computational model accounting for our experimental results. Consistent with the probabilistic language of thought approach to cognitive modeling, our model formalizes multisensory representations as symbolic "computer programs" and uses Bayesian inference to learn these representations. Because the model demonstrates how the acquisition and use of amodal, multisensory representations can underlie cross-modal transfer of knowledge, and because the model accounts for subjects' experimental performances, our work lends credence to the Multisensory Hypothesis. Overall, our work suggests that people automatically extract and represent objects' and events' intrinsic properties, and use these properties to process and understand the same (and similar) objects and events when they are perceived through novel sensory modalities.

  1. Multisensory Convergence of Visual and Vestibular Heading Cues in the Pursuit Area of the Frontal Eye Field.

    PubMed

    Gu, Yong; Cheng, Zhixian; Yang, Lihua; DeAngelis, Gregory C; Angelaki, Dora E

    2016-09-01

    Both visual and vestibular sensory cues are important for perceiving one's direction of heading during self-motion. Previous studies have identified multisensory, heading-selective neurons in the dorsal medial superior temporal area (MSTd) and the ventral intraparietal area (VIP). Both MSTd and VIP have strong recurrent connections with the pursuit area of the frontal eye field (FEFsem), but whether FEFsem neurons may contribute to multisensory heading perception remain unknown. We characterized the tuning of macaque FEFsem neurons to visual, vestibular, and multisensory heading stimuli. About two-thirds of FEFsem neurons exhibited significant heading selectivity based on either vestibular or visual stimulation. These multisensory neurons shared many properties, including distributions of tuning strength and heading preferences, with MSTd and VIP neurons. Fisher information analysis also revealed that the average FEFsem neuron was almost as sensitive as MSTd or VIP cells. Visual and vestibular heading preferences in FEFsem tended to be either matched (congruent cells) or discrepant (opposite cells), such that combined stimulation strengthened heading selectivity for congruent cells but weakened heading selectivity for opposite cells. These findings demonstrate that, in addition to oculomotor functions, FEFsem neurons also exhibit properties that may allow them to contribute to a cortical network that processes multisensory heading cues.

  2. The fMRI BOLD response to unisensory and multisensory smoking cues in nicotine-dependent adults

    PubMed Central

    Cortese, Bernadette M.; Uhde, Thomas W.; Brady, Kathleen T.; McClernon, F. Joseph; Yang, Qing X.; Collins, Heather R.; LeMatty, Todd; Hartwell, Karen J.

    2015-01-01

    Given that the vast majority of functional magnetic resonance imaging (fMRI) studies of drug cue reactivity use unisensory visual cues, but that multisensory cues may elicit greater craving-related brain responses, the current study sought to compare the fMRI BOLD response to unisensory visual and multisensory, visual plus odor, smoking cues in 17 nicotine-dependent adult cigarette smokers. Brain activation to smoking-related, compared to neutral, pictures was assessed under cigarette smoke and odorless odor conditions. While smoking pictures elicited a pattern of activation consistent with the addiction literature, the multisensory (odor + picture) smoking cues elicited significantly greater and more widespread activation in mainly frontal and temporal regions. BOLD signal elicited by the multi-sensory, but not unisensory cues, was significantly related to participants’ level of control over craving as well. Results demonstrated that the co-presentation of cigarette smoke odor with smoking-related visual cues, compared to the visual cues alone, elicited greater levels of craving-related brain activation in key regions implicated in reward. These preliminary findings support future research aimed at a better understanding of multisensory integration of drug cues and craving. PMID:26475784

  3. The development of fluorescence turn-on probe for Al(III) sensing and live cell nucleus-nucleoli staining

    NASA Astrophysics Data System (ADS)

    Saini, Anoop Kumar; Sharma, Vinay; Mathur, Pradeep; Shaikh, Mobin M.

    2016-10-01

    The morphology of nucleus and nucleolus is powerful indicator of physiological and pathological conditions. The specific staining of nucleolus recently gained much attention due to the limited and expensive availability of the only existing stain “SYTO RNA-Select”. Here, a new multifunctional salen type ligand (L1) and its Al3+ complex (1) are designed and synthesized. L1 acts as a chemosensor for Al3+ whereas 1 demonstrates specific staining of nucleus as well as nucleoli. The binding of 1 with nucleic acid is probed by DNase and RNase digestion in stained cells. 1 shows an excellent photostability, which is a limitation for existing nucleus stains during long term observations. 1 is assumed to be a potential candidate as an alternative to expensive commercial dyes for nucleus and nucleoli staining.

  4. The development of fluorescence turn-on probe for Al(III) sensing and live cell nucleus-nucleoli staining

    PubMed Central

    Saini, Anoop Kumar; Sharma, Vinay; Mathur, Pradeep; Shaikh, Mobin M.

    2016-01-01

    The morphology of nucleus and nucleolus is powerful indicator of physiological and pathological conditions. The specific staining of nucleolus recently gained much attention due to the limited and expensive availability of the only existing stain “SYTO RNA-Select”. Here, a new multifunctional salen type ligand (L1) and its Al3+ complex (1) are designed and synthesized. L1 acts as a chemosensor for Al3+ whereas 1 demonstrates specific staining of nucleus as well as nucleoli. The binding of 1 with nucleic acid is probed by DNase and RNase digestion in stained cells. 1 shows an excellent photostability, which is a limitation for existing nucleus stains during long term observations. 1 is assumed to be a potential candidate as an alternative to expensive commercial dyes for nucleus and nucleoli staining. PMID:27721431

  5. EHF multifunction phased array antenna

    NASA Astrophysics Data System (ADS)

    Solbach, Klaus

    1986-07-01

    The design of a low cost demonstration EHF multifunction-phased array antenna is described. Both, the radiating elements and the phase-shifter circuits are realized on microstrip substrate material in order to allow photolithographic batch fabrication. Self-encapsulated beam-lead PIN-diodes are employed as the electronic switch elements to avoid expensive hermetic encapsulation of the semiconductors or complete circuits. A space-feed using a horn-radiator to illuminate the array from the front-side is found to be the simplest and most inexpensive feed. The phased array antenna thus operates as a reflect-array, the antenna elements employed in a dual role for the collection of energy from the feed-horn and for the re-radiation of the phase-shifted waves (in transmit-mode). The antenna is divided into modules containing the radiator/phase-shifter plate plus drive- and BITE-circuitry at the back. Both drive- and BITE-components use gate-array integrated circuits especially designed for the purpose. Several bus-systems are used to supply bias and logical data flows to the modules. The beam-steering unit utilizes several signal processors and high-speed discrete adder circuits to combine the pointing, frequency and beam-shape information from the radar system computer with the stored phase-shift codes for the array elements. Since space, weight and power consumption are prime considerations only the most advanced technology is used in the design of both the microwave and the digital/drive circuitry.

  6. Multifunctional nanocomposite foams for space applications

    NASA Astrophysics Data System (ADS)

    Rollins, Diandra J.

    Materials combined with a small amount of nanoparticles offer new possibilities in the synthesizing of multifunctional materials. Graphene nanoplatelets (GnP) are multifunctional nanoreinforcing agents consisting of stacks of graphene sheets with comparable properties to a single graphene layer at an overall lower cost in a more robust form. Such particles have been shown to have good thermal, mechanical and electrical properties. In addition, a low density multifunctional nanocomposite foam has the potential for multiple applications and potential use for the aerospace industry. This dissertation investigates two different microporous (foam) polymers that are modified by the addition of GnP to combat this density effect to improve the foam's macroscopic properties Three sizes of GnP with varying aspect ratio were used to improve the polymeric foams' dielectric, electrical and mechanical properties. (Abstract shortened by ProQuest.).

  7. Multifunctional materials for bone cancer treatment

    PubMed Central

    Marques, Catarina; Ferreira, José MF; Andronescu, Ecaterina; Ficai, Denisa; Sonmez, Maria; Ficai, Anton

    2014-01-01

    The purpose of this review is to present the most recent findings in bone tissue engineering. Special attention is given to multifunctional materials based on collagen and collagen–hydroxyapatite composites used for skin and bone cancer treatments. The multi-functionality of these materials was obtained by adding to the base regenerative grafts proper components, such as ferrites (magnetite being the most important representative), cytostatics (cisplatin, carboplatin, vincristine, methotrexate, paclitaxel, doxorubicin), silver nanoparticles, antibiotics (anthracyclines, geldanamycin), and/or analgesics (ibuprofen, fentanyl). The suitability of complex systems for the intended applications was systematically analyzed. The developmental possibilities of multifunctional materials with regenerative and curative roles (antitumoral as well as pain management) in the field of skin and bone cancer treatment are discussed. It is worth mentioning that better materials are likely to be developed by combining conventional and unconventional experimental strategies. PMID:24920907

  8. Surface albedo of cometary nucleus

    NASA Astrophysics Data System (ADS)

    Mukai, T.; Mukai, S.

    A variation of the albedo on the illuminated disk of a comet nucleus is estimated, taking into account the multiple reflection of incident light due to small scale roughness. The dependences of the average albedo over the illuminated disk on the degree of roughness and on the complex refractive index of the surface materials are examined. The variation estimates are compared with measurements of the nucleus albedo of Comet Halley (Reitsema et al., 1987).

  9. Multifunctional Material Systems for Reconfigurable Antennas in Superconfigurable Structures

    DTIC Science & Technology

    2016-01-05

    AFRL-AFOSR-VA-TR-2016-0128 Multifunctional Material Systems for Reconfigurable Antennas Gregory Huff TEXAS ENGINEERING EXPERIMENT STATION COLLEGE...Multifunctional Material Systems for Reconfigurable Antennas in Superconfigurable Structures 5a. CONTRACT NUMBER FA9550-12-1-0090 5b. GRANT NUMBER...antenna systems enabled by fluidic dispersions of nanoparticles and multifunctional composites. This final report summarizes major research

  10. Complex Multifunctional Polymer/Carbon-Nanotube Composites

    NASA Technical Reports Server (NTRS)

    Patel, Pritesh; Balasubramaniyam, Gobinath; Chen, Jian

    2009-01-01

    A methodology for developing complex multifunctional materials that consist of or contain polymer/carbon-nanotube composites has been conceived. As used here, "multifunctional" signifies having additional and/or enhanced physical properties that polymers or polymer-matrix composites would not ordinarily be expected to have. Such properties include useful amounts of electrical conductivity, increased thermal conductivity, and/or increased strength. In the present methodology, these properties are imparted to a given composite through the choice and processing of its polymeric and CNT constituents.

  11. Novel hybrid multifunctional magnetoelectric porous composite films

    NASA Astrophysics Data System (ADS)

    Martins, P.; Gonçalves, R.; Lopes, A. C.; Venkata Ramana, E.; Mendiratta, S. K.; Lanceros-Mendez, S.

    2015-12-01

    Novel multifunctional porous films have been developed by the integration of magnetic CoFe2O4 (CFO) nanoparticles into poly(vinylidene fluoride)-Trifuoroethylene (P(VDF-TrFE)), taking advantage of the synergies of the magnetostrictive filler and the piezoelectric polymer. The porous films show a piezoelectric response with an effective d33 coefficient of -22 pC/N-1, a maximum magnetization of 12 emu g-1 and a maximum magnetoelectric coefficient of 9 mV cm-1 Oe-1. In this way, a multifunctional membrane has been developed suitable for advanced applications ranging from biomedical to water treatment.

  12. Multisensory integration in hemianopia and unilateral spatial neglect: Evidence from the sound induced flash illusion.

    PubMed

    Bolognini, Nadia; Convento, Silvia; Casati, Carlotta; Mancini, Flavia; Brighina, Filippo; Vallar, Giuseppe

    2016-07-01

    Recent neuropsychological evidence suggests that acquired brain lesions can, in some instances, abolish the ability to integrate inputs from different sensory modalities, disrupting multisensory perception. We explored the ability to perceive multisensory events, in particular the integrity of audio-visual processing in the temporal domain, in brain-damaged patients with visual field defects (VFD), or with unilateral spatial neglect (USN), by assessing their sensitivity to the 'Sound-Induced Flash Illusion' (SIFI). The study yielded two key findings. Firstly, the 'fission' illusion (namely, seeing multiple flashes when a single flash is paired with multiple sounds) is reduced in both left- and right-brain-damaged patients with VFD, but not in right-brain-damaged patients with left USN. The disruption of the fission illusion is proportional to the extent of the occipital damage. Secondly, a reliable 'fusion' illusion (namely, seeing less flashes when a single sound is paired with multiple flashes) is evoked in USN patients, but neither in VFD patients nor in healthy participants. A control experiment showed that the fusion, but not the fission, illusion is lost in older participants (>50 year-old), as compared with younger healthy participants (<30 year-old). This evidence indicates that the fission and fusion illusions are dissociable multisensory phenomena, altered differently by impairments of visual perception (i.e. VFD) and spatial attention (i.e. USN). The occipital cortex represents a key cortical site for binding auditory and visual stimuli in the SIFI, while damage to right-hemisphere areas mediating spatial attention and awareness does not prevent the integration of audio-visual inputs in the temporal domain.

  13. The rapid distraction of attentional resources toward the source of incongruent stimulus input during multisensory conflict

    PubMed Central

    Donohue, Sarah E.; Todisco, Alexandra E.; Woldorff, Marty G.

    2013-01-01

    Neuroimaging work on multisensory conflict suggests that the relevant modality receives enhanced processing in the face of incongruency. However, the degree of stimulus processing in the irrelevant modality and the temporal cascade of the attentional modulations in either the relevant or irrelevant modalities are unknown. Here, we employed an audiovisual conflict paradigm with a sensory probe in the task-irrelevant modality (vision) to gauge the attentional allocation to that modality. Event-related potentials (ERPs) were recorded as subjects attended to and discriminated spoken auditory letters while ignoring simultaneous bilateral visual letter stimuli that were either fully congruent, fully incongruent, or partially incongruent (one side incongruent, one congruent) with the auditory stimulation. Half of the audiovisual letter stimuli were followed 500-700 ms later by a bilateral visual probe stimulus. As expected, ERPs to the audiovisual stimuli showed an incongruency ERP effect (fully incongruent versus fully congruent) of an enhanced, centrally distributed, negative-polarity wave starting ~250 ms. More critically here, the sensory ERP components to the visual probes were larger when they followed fully incongruent versus fully congruent multisensory stimuli, with these enhancements greatest on fully incongruent trials with the slowest response times. In addition, on the slowest-response partially incongruent trials, the P2 sensory component to the visual probes was larger contralateral to the preceding incongruent visual stimulus. These data suggest that, in response to conflicting multisensory stimulus input, the initial cognitive effect is a capture of attention by the incongruent irrelevant-modality input, pulling neural processing resources toward that modality, resulting in rapid enhancement, rather than rapid suppression, of that input. PMID:23249355

  14. Multisensory Bayesian Inference Depends on Synapse Maturation during Training: Theoretical Analysis and Neural Modeling Implementation.

    PubMed

    Ursino, Mauro; Cuppini, Cristiano; Magosso, Elisa

    2017-03-01

    Recent theoretical and experimental studies suggest that in multisensory conditions, the brain performs a near-optimal Bayesian estimate of external events, giving more weight to the more reliable stimuli. However, the neural mechanisms responsible for this behavior, and its progressive maturation in a multisensory environment, are still insufficiently understood. The aim of this letter is to analyze this problem with a neural network model of audiovisual integration, based on probabilistic population coding-the idea that a population of neurons can encode probability functions to perform Bayesian inference. The model consists of two chains of unisensory neurons (auditory and visual) topologically organized. They receive the corresponding input through a plastic receptive field and reciprocally exchange plastic cross-modal synapses, which encode the spatial co-occurrence of visual-auditory inputs. A third chain of multisensory neurons performs a simple sum of auditory and visual excitations. The work includes a theoretical part and a computer simulation study. We show how a simple rule for synapse learning (consisting of Hebbian reinforcement and a decay term) can be used during training to shrink the receptive fields and encode the unisensory likelihood functions. Hence, after training, each unisensory area realizes a maximum likelihood estimate of stimulus position (auditory or visual). In cross-modal conditions, the same learning rule can encode information on prior probability into the cross-modal synapses. Computer simulations confirm the theoretical results and show that the proposed network can realize a maximum likelihood estimate of auditory (or visual) positions in unimodal conditions and a Bayesian estimate, with moderate deviations from optimality, in cross-modal conditions. Furthermore, the model explains the ventriloquism illusion and, looking at the activity in the multimodal neurons, explains the automatic reweighting of auditory and visual inputs

  15. Sleeping on the rubber-hand illusion: Memory reactivation during sleep facilitates multisensory recalibration.

    PubMed

    Honma, Motoyasu; Plass, John; Brang, David; Florczak, Susan M; Grabowecky, Marcia; Paller, Ken A

    2016-01-01

    Plasticity is essential in body perception so that physical changes in the body can be accommodated and assimilated. Multisensory integration of visual, auditory, tactile, and proprioceptive signals contributes both to conscious perception of the body's current state and to associated learning. However, much is unknown about how novel information is assimilated into body perception networks in the brain. Sleep-based consolidation can facilitate various types of learning via the reactivation of networks involved in prior encoding or through synaptic down-scaling. Sleep may likewise contribute to perceptual learning of bodily information by providing an optimal time for multisensory recalibration. Here we used methods for targeted memory reactivation (TMR) during slow-wave sleep to examine the influence of sleep-based reactivation of experimentally induced alterations in body perception. The rubber-hand illusion was induced with concomitant auditory stimulation in 24 healthy participants on 3 consecutive days. While each participant was sleeping in his or her own bed during intervening nights, electrophysiological detection of slow-wave sleep prompted covert stimulation with either the sound heard during illusion induction, a counterbalanced novel sound, or neither. TMR systematically enhanced feelings of bodily ownership after subsequent inductions of the rubber-hand illusion. TMR also enhanced spatial recalibration of perceived hand location in the direction of the rubber hand. This evidence for a sleep-based facilitation of a body-perception illusion demonstrates that the spatial recalibration of multisensory signals can be altered overnight to stabilize new learning of bodily representations. Sleep-based memory processing may thus constitute a fundamental component of body-image plasticity.

  16. Sleeping on the rubber-hand illusion: Memory reactivation during sleep facilitates multisensory recalibration

    PubMed Central

    Honma, Motoyasu; Plass, John; Brang, David; Florczak, Susan M.; Grabowecky, Marcia; Paller, Ken A.

    2016-01-01

    Plasticity is essential in body perception so that physical changes in the body can be accommodated and assimilated. Multisensory integration of visual, auditory, tactile, and proprioceptive signals contributes both to conscious perception of the body’s current state and to associated learning. However, much is unknown about how novel information is assimilated into body perception networks in the brain. Sleep-based consolidation can facilitate various types of learning via the reactivation of networks involved in prior encoding or through synaptic down-scaling. Sleep may likewise contribute to perceptual learning of bodily information by providing an optimal time for multisensory recalibration. Here we used methods for targeted memory reactivation (TMR) during slow-wave sleep to examine the influence of sleep-based reactivation of experimentally induced alterations in body perception. The rubber-hand illusion was induced with concomitant auditory stimulation in 24 healthy participants on 3 consecutive days. While each participant was sleeping in his or her own bed during intervening nights, electrophysiological detection of slow-wave sleep prompted covert stimulation with either the sound heard during illusion induction, a counterbalanced novel sound, or neither. TMR systematically enhanced feelings of bodily ownership after subsequent inductions of the rubber-hand illusion. TMR also enhanced spatial recalibration of perceived hand location in the direction of the rubber hand. This evidence for a sleep-based facilitation of a body-perception illusion demonstrates that the spatial recalibration of multisensory signals can be altered overnight to stabilize new learning of bodily representations. Sleep-based memory processing may thus constitute a fundamental component of body-image plasticity. PMID:28184322

  17. Functional mobility and balance in community-dwelling elderly submitted to multisensory versus strength exercises

    PubMed Central

    Alfieri, Fábio Marcon; Riberto, Marcelo; Gatz, Lucila Silveira; Ribeiro, Carla Paschoal Corsi; Lopes, José Augusto Fernandes; Santarém, José Maria; Battistella, Linamara Rizzo

    2010-01-01

    It is well documented that aging impairs balance and functional mobility. The objective of this study was to compare the efficacy of multisensory versus strength exercises on these parameters. We performed a simple blinded randomized controlled trial with 46 community-dwelling elderly allocated to strength ([GST], N = 23, 70.2-years-old ± 4.8 years) or multisensory ([GMS], N = 23, 68.8-years-old ± 5.9 years) exercises twice a week for 12 weeks. Subjects were evaluated by blinded raters using the timed ‘up and go’ test (TUG), the Guralnik test battery, and a force platform. By the end of the treatment, the GMS group showed a significant improvement in TUG (9.1 ± 1.9 seconds (s) to 8.0 ± 1.0 s, P = 0.002); Guralnik test battery (10.6 ± 1.2 to 11.3 ± 0.8 P = 0.009); lateromedial (6.1 ± 11.7 cm to 3.1 ± 1.6 cm, P = 0.02) and anteroposterior displacement (4.7 ± 4.2 cm to 3.4 ± 1.0 cm, P = 0.03), which were not observed in the GST group. These results reproduce previous findings in the literature and mean that the stimulus to sensibility results in better achievements for the control of balance and dynamic activities. Multisensory exercises were shown to be more efficacious than strength exercises to improve functional mobility. PMID:20711437

  18. Multisensory Integration in Non-Human Primates during a Sensory-Motor Task.

    PubMed

    Lanz, Florian; Moret, Véronique; Rouiller, Eric Michel; Loquet, Gérard

    2013-01-01

    Daily our central nervous system receives inputs via several sensory modalities, processes them and integrates information in order to produce a suitable behavior. The amazing part is that such a multisensory integration brings all information into a unified percept. An approach to start investigating this property is to show that perception is better and faster when multimodal stimuli are used as compared to unimodal stimuli. This forms the first part of the present study conducted in a non-human primate's model (n = 2) engaged in a detection sensory-motor task where visual and auditory stimuli were displayed individually or simultaneously. The measured parameters were the reaction time (RT) between stimulus and onset of arm movement, successes and errors percentages, as well as the evolution as a function of time of these parameters with training. As expected, RTs were shorter when the subjects were exposed to combined stimuli. The gains for both subjects were around 20 and 40 ms, as compared with the auditory and visual stimulus alone, respectively. Moreover the number of correct responses increased in response to bimodal stimuli. We interpreted such multisensory advantage through redundant signal effect which decreases perceptual ambiguity, increases speed of stimulus detection, and improves performance accuracy. The second part of the study presents single-unit recordings derived from the premotor cortex (PM) of the same subjects during the sensory-motor task. Response patterns to sensory/multisensory stimulation are documented and specific type proportions are reported. Characterization of bimodal neurons indicates a mechanism of audio-visual integration possibly through a decrease of inhibition. Nevertheless the neural processing leading to faster motor response from PM as a polysensory association cortical area remains still unclear.

  19. Multisensory and modality specific processing of visual speech in different regions of the premotor cortex

    PubMed Central

    Callan, Daniel E.; Jones, Jeffery A.; Callan, Akiko

    2014-01-01

    Behavioral and neuroimaging studies have demonstrated that brain regions involved with speech production also support speech perception, especially under degraded conditions. The premotor cortex (PMC) has been shown to be active during both observation and execution of action (“Mirror System” properties), and may facilitate speech perception by mapping unimodal and multimodal sensory features onto articulatory speech gestures. For this functional magnetic resonance imaging (fMRI) study, participants identified vowels produced by a speaker in audio-visual (saw the speaker's articulating face and heard her voice), visual only (only saw the speaker's articulating face), and audio only (only heard the speaker's voice) conditions with varying audio signal-to-noise ratios in order to determine the regions of the PMC involved with multisensory and modality specific processing of visual speech gestures. The task was designed so that identification could be made with a high level of accuracy from visual only stimuli to control for task difficulty and differences in intelligibility. The results of the functional magnetic resonance imaging (fMRI) analysis for visual only and audio-visual conditions showed overlapping activity in inferior frontal gyrus and PMC. The left ventral inferior premotor cortex (PMvi) showed properties of multimodal (audio-visual) enhancement with a degraded auditory signal. The left inferior parietal lobule and right cerebellum also showed these properties. The left ventral superior and dorsal premotor cortex (PMvs/PMd) did not show this multisensory enhancement effect, but there was greater activity for the visual only over audio-visual conditions in these areas. The results suggest that the inferior regions of the ventral premotor cortex are involved with integrating multisensory information, whereas, more superior and dorsal regions of the PMC are involved with mapping unimodal (in this case visual) sensory features of the speech signal with

  20. The sound-induced flash illusion reveals dissociable age-related effects in multisensory integration

    PubMed Central

    McGovern, David P.; Roudaia, Eugenie; Stapleton, John; McGinnity, T. Martin; Newell, Fiona N.

    2014-01-01

    While aging can lead to significant declines in perceptual and cognitive function, the effects of age on multisensory integration, the process in which the brain combines information across the senses, are less clear. Recent reports suggest that older adults are susceptible to the sound-induced flash illusion (Shams et al., 2000) across a much wider range of temporal asynchronies than younger adults (Setti et al., 2011). To assess whether this cost for multisensory integration is a general phenomenon of combining asynchronous audiovisual input, we compared the time courses of two variants of the sound-induced flash illusion in young and older adults: the fission illusion, where one flash accompanied by two beeps appears as two flashes, and the fusion illusion, where two flashes accompanied by one beep appear as one flash. Twenty-five younger (18–30 years) and older (65+ years) adults were required to report whether they perceived one or two flashes, whilst ignoring irrelevant auditory beeps, in bimodal trials where auditory and visual stimuli were separated by one of six stimulus onset asynchronies (SOAs). There was a marked difference in the pattern of results for the two variants of the illusion. In conditions known to produce the fission illusion, older adults were significantly more susceptible to the illusion at longer SOAs compared to younger participants. In contrast, the performance of the younger and older groups was almost identical in conditions known to produce the fusion illusion. This surprising difference between sound-induced fission and fusion in older adults suggests dissociable age-related effects in multisensory integration, consistent with the idea that these illusions are mediated by distinct neural mechanisms. PMID:25309430

  1. Stepping to phase-perturbed metronome cues: multisensory advantage in movement synchrony but not correction

    PubMed Central

    Wright, Rachel L.; Spurgeon, Laura C.; Elliott, Mark T.

    2014-01-01

    Humans can synchronize movements with auditory beats or rhythms without apparent effort. This ability to entrain to the beat is considered automatic, such that any perturbations are corrected for, even if the perturbation was not consciously noted. Temporal correction of upper limb (e.g., finger tapping) and lower limb (e.g., stepping) movements to a phase perturbed auditory beat usually results in individuals being back in phase after just a few beats. When a metronome is presented in more than one sensory modality, a multisensory advantage is observed, with reduced temporal variability in finger tapping movements compared to unimodal conditions. Here, we investigate synchronization of lower limb movements (stepping in place) to auditory, visual and combined auditory-visual (AV) metronome cues. In addition, we compare movement corrections to phase advance and phase delay perturbations in the metronome for the three sensory modality conditions. We hypothesized that, as with upper limb movements, there would be a multisensory advantage, with stepping variability being lowest in the bimodal condition. As such, we further expected correction to the phase perturbation to be quickest in the bimodal condition. Our results revealed lower variability in the asynchronies between foot strikes and the metronome beats in the bimodal condition, compared to unimodal conditions. However, while participants corrected substantially quicker to perturbations in auditory compared to visual metronomes, there was no multisensory advantage in the phase correction task—correction under the bimodal condition was almost identical to the auditory-only (AO) condition. On the whole, we noted that corrections in the stepping task were smaller than those previously reported for finger tapping studies. We conclude that temporal corrections are not only affected by the reliability of the sensory information, but also the complexity of the movement itself. PMID:25309397

  2. Neural functional organization of hallucinations in schizophrenia: multisensory dissolution of pathological emergence in consciousness.

    PubMed

    Jardri, Renaud; Pins, Delphine; Bubrovszky, Maxime; Lucas, Bernard; Lethuc, Vianney; Delmaire, Christine; Vantyghem, Vincent; Despretz, Pascal; Thomas, Pierre

    2009-06-01

    Although complex hallucinations are extremely vivid, painful symptoms in schizophrenia, little is known about the underlying mechanisms of multisensory integration in such a phenomenon. We investigated the neural basis of these altered states of consciousness in a patient with schizophrenia, by combining state of the art neuroscientific exploratory methods like functional MRI, diffusion tensor imaging, cortical thickness analysis, electrical source reconstruction and trans-cranial magnetic stimulation. The results shed light on the functional architecture of the hallucinatory processes, in which unimodal information from different modalities is strongly functionally connected to higher-order integrative areas.

  3. Behavioral and Neural Foundations of Multisensory Face-Voice Perception in Infancy.

    PubMed

    Hyde, Daniel C; Flom, Ross; Porter, Chris L

    In this article, we describe behavioral and neurophysiological evidence for infants' multimodal face-voice perception. We argue that the behavioral development of face-voice perception, like multimodal perception more broadly, is consistent with the intersensory redundancy hypothesis (IRH). Furthermore, we highlight that several recently observed features of the neural responses in infants converge with the behavioral predictions of the intersensory redundancy hypothesis. Finally, we discuss the potential benefits of combining brain and behavioral measures to study multisensory processing, as well as some applications of this work for atypical development.

  4. Sensitivity of cross sections for elastic nucleus-nucleus scattering to halo nucleus density distributions

    SciTech Connect

    Alkhazov, G. D.; Sarantsev, V. V.

    2012-12-15

    In order to clear up the sensitivity of the nucleus-nucleus scattering to the nuclear matter distributions in exotic halo nuclei, we have calculated differential cross sections for elastic scattering of the {sup 6}He and {sup 11}Li nuclei on several nuclear targets at the energy of 0.8 GeV/nucleon with different assumed nuclear density distributions in {sup 6}He and {sup 11}Li.

  5. Brain and language: evidence for neural multifunctionality.

    PubMed

    Cahana-Amitay, Dalia; Albert, Martin L

    2014-01-01

    This review paper presents converging evidence from studies of brain damage and longitudinal studies of language in aging which supports the following thesis: the neural basis of language can best be understood by the concept of neural multifunctionality. In this paper the term "neural multifunctionality" refers to incorporation of nonlinguistic functions into language models of the intact brain, reflecting a multifunctional perspective whereby a constant and dynamic interaction exists among neural networks subserving cognitive, affective, and praxic functions with neural networks specialized for lexical retrieval, sentence comprehension, and discourse processing, giving rise to language as we know it. By way of example, we consider effects of executive system functions on aspects of semantic processing among persons with and without aphasia, as well as the interaction of executive and language functions among older adults. We conclude by indicating how this multifunctional view of brain-language relations extends to the realm of language recovery from aphasia, where evidence of the influence of nonlinguistic factors on the reshaping of neural circuitry for aphasia rehabilitation is clearly emerging.

  6. Multifunctional lubricant additives and compositions thereof

    SciTech Connect

    Farng, L.O.; Horodysky, A.G.

    1991-03-26

    This paper discusses an antioxidant/ antiwear/extreme pressure/load carrying lubricant composition. It comprises a major proportion of an oil of lubricating viscosity or grease or other solid lubricant prepared therefrom and a minor amount of an ashless multifunctional antioxidant/antiwear/extreme pressure/load carrying additive product comprising a thiophosphate derived from a dihydrocarbyl dithiocarbamate.

  7. Multifunctional, High-Temperature Nanocomposites

    NASA Technical Reports Server (NTRS)

    Connell, John W.; Smith, Joseph G.; Siochi, Emilie J.; Working, Dennis C.; Criss, Jim M.; Watson, Kent A.; Delozier, Donavon M.; Ghose, Sayata

    2007-01-01

    In experiments conducted as part of a continuing effort to incorporate multifunctionality into advanced composite materials, blends of multi-walled carbon nanotubes and a resin denoted gPETI-330 h (wherein gPETI h is an abbreviation for gphenylethynyl-terminated imide h) were prepared, characterized, and fabricated into moldings. PETI-330 was selected as the matrix resin in these experiments because of its low melt viscosity (<10 poise at a temperature of 280 C), excellent melt stability (lifetime >2 hours at 280 C), and high temperature performance (>1,000 hours at 288 C). The multi-walled carbon nanotubes (MWCNTs), obtained from the University of Kentucky, were selected because of their electrical and thermal conductivity and their small diameters. The purpose of these experiments was to determine the combination of thermal, electrical, and mechanical properties achievable while still maintaining melt processability. The PETI-330/MWCNT mixtures were prepared at concentrations ranging from 3 to 25 weight-percent of MWCNTs by dry mixing of the constituents in a ball mill using zirconia beads. The resulting powders were characterized for degree of mixing and thermal and rheological properties. The neat resin was found to have melt viscosity between 5 and 10 poise. At 280 C and a fixed strain rate, the viscosity was found to increase with time. At this temperature, the phenylethynyl groups do not readily react and so no significant curing of the resin occurred. For MWCNT-filled samples, melt viscosity was reasonably steady at 280 C and was greater in samples containing greater proportions of MWCNTs. The melt viscosity for 20 weightpercent of MWCNTs was found to be .28,000 poise, which is lower than the initial estimated allowable maximum value of 60,000 poise for injection molding. Hence, MWCNT loadings of as much as 20 percent were deemed to be suitable compositions for scale-up. High-resolution scanning electron microscopy (HRSEM) showed the MWCNTs to be well

  8. Magnetically Attached Multifunction Maintenance Rover

    NASA Technical Reports Server (NTRS)

    Bar-Cohen, Yoseph; Joffe, Benjamin

    2005-01-01

    A versatile mobile telerobot, denoted the magnetically attached multifunction maintenance rover (MAGMER), has been proposed for use in the inspection and maintenance of the surfaces of ships, tanks containing petrochemicals, and other large ferromagnetic structures. As its name suggests, this robot would utilize magnetic attraction to adhere to a structure. As it moved along the surface of the structure, the MAGMER would perform tasks that could include close-up visual inspection by use of video cameras, various sensors, and/or removal of paint by water-jet blasting, laser heating, or induction heating. The water-jet nozzles would be mounted coaxially within compressed-air-powered venturi nozzles that would collect the paint debris dislodged by the jets. The MAGMER would be deployed, powered, and controlled from a truck, to which it would be connected by hoses for water, compressed air, and collection of debris and by cables for electric power and communication (see Figure 1). The operation of the MAGMER on a typical large structure would necessitate the use of long cables and hoses, which can be heavy. To reduce the load of the hoses and cables on the MAGMER and thereby ensure its ability to adhere to vertical and overhanging surfaces, the hoses and cables would be paid out through telescopic booms that would be parts of a MAGMER support system. The MAGMER would move by use of four motorized, steerable wheels, each of which would be mounted in an assembly that would include permanent magnets and four pole pieces (see Figure 2). The wheels would protrude from between the pole pieces by only about 3 mm, so that the gap between the pole pieces and the ferromagnetic surface would be just large enough to permit motion along the surface but not so large as to reduce the magnetic attraction excessively. In addition to the wheel assemblies, the MAGMER would include magnetic adherence enhancement fixtures, which would comprise arrays of permanent magnets and pole pieces

  9. A neural model to study sensory abnormalities and multisensory effects in autism.

    PubMed

    Noriega, Gerardo

    2015-03-01

    Computational modeling plays an increasingly prominent role in complementing critical research in the genetics, neuroscience, and psychology of autism. This paper presents a model that supports the notion that weak central coherence, a processing bias for features and local information, may be responsible for perception abnormalities by failing to "control" sensory issues in autism. The model has a biologically plausible architecture based on a self-organizing map. It incorporates temporal information in input stimuli, with emphasis on real auditory signals, and provides a mechanism to model multisensory effects. Through comprehensive simulations the paper studies the effect of a control mechanism (akin to central coherence) in compensating the effects of temporal information in the presentation of stimuli, sensory abnormalities, and crosstalk between domains. The mechanism is successful in balancing out timing effects, basic hypersensitivities and, to a lesser degree, multisensory effects. An analysis of the effect of the control mechanism's onset time on performance suggests that most of the potential benefits are still attainable even when started rather late in the learning process. This high level of adaptability shown by the neural network highlights the importance of appropriate teaching and intervention throughout the lifetime of persons with autism and other neurological disorders.

  10. Multisensory distortions of the hand have differential effects on tactile perception.

    PubMed

    Treshi-marie Perera, A; Newport, Roger; McKenzie, Kirsten J

    2015-11-01

    Research has suggested that altering the perceived shape and size of the body image significantly affects perception of somatic events. The current study investigated how multisensory illusions applied to the body altered tactile perception using the somatic signal detection task. Thirty-one healthy volunteers were asked to report the presence or absence of near-threshold tactile stimuli delivered to the index finger under three multisensory illusion conditions: stretched finger, shrunken finger and detached finger, as well as a veridical baseline condition. Both stretching and shrinking the stimulated finger enhanced correct touch detections; however, the mechanisms underlying this increase were found to be different. In contrast, the detached appearance reduced false touch reports-possibly due to reduced tactile noise, as a result of attention being directed to the tip of the finger only. These findings suggest that distorted representations of the body could have different modulatory effects on attention to touch and provide a link between perceived body representation and somatosensory decision-making.

  11. Does media multitasking always hurt? A positive correlation between multitasking and multisensory integration.

    PubMed

    Lui, Kelvin F H; Wong, Alan C-N

    2012-08-01

    Heavy media multitaskers have been found to perform poorly in certain cognitive tasks involving task switching, selective attention, and working memory. An account for this is that with a breadth-biased style of cognitive control, multitaskers tend to pay attention to various information available in the environment, without sufficient focus on the information most relevant to the task at hand. This cognitive style, however, may not cause a general deficit in all kinds of tasks. We tested the hypothesis that heavy media multitaskers would perform better in a multisensory integration task than would others, due to their extensive experience in integrating information from different modalities. Sixty-three participants filled out a questionnaire about their media usage and completed a visual search task with and without synchronous tones (pip-and-pop paradigm). It was found that a higher degree of media multitasking was correlated with better multisensory integration. The fact that heavy media multitaskers are not deficient in all kinds of cognitive tasks suggests that media multitasking does not always hurt.

  12. Multisensory Integration and Behavioral Plasticity in Sharks from Different Ecological Niches

    PubMed Central

    Gardiner, Jayne M.; Atema, Jelle; Hueter, Robert E.; Motta, Philip J.

    2014-01-01

    The underwater sensory world and the sensory systems of aquatic animals have become better understood in recent decades, but typically have been studied one sense at a time. A comprehensive analysis of multisensory interactions during complex behavioral tasks has remained a subject of discussion without experimental evidence. We set out to generate a general model of multisensory information extraction by aquatic animals. For our model we chose to analyze the hierarchical, integrative, and sometimes alternate use of various sensory systems during the feeding sequence in three species of sharks that differ in sensory anatomy and behavioral ecology. By blocking senses in different combinations, we show that when some of their normal sensory cues were unavailable, sharks were often still capable of successfully detecting, tracking and capturing prey by switching to alternate sensory modalities. While there were significant species differences, odor was generally the first signal detected, leading to upstream swimming and wake tracking. Closer to the prey, as more sensory cues became available, the preferred sensory modalities varied among species, with vision, hydrodynamic imaging, electroreception, and touch being important for orienting to, striking at, and capturing the prey. Experimental deprivation of senses showed how sharks exploit the many signals that comprise their sensory world, each sense coming into play as they provide more accurate information during the behavioral sequence of hunting. The results may be applicable to aquatic hunting in general and, with appropriate modification, to other types of animal behavior. PMID:24695492

  13. Behavioral, perceptual, and neural alterations in sensory and multisensory function in autism spectrum disorder.

    PubMed

    Baum, Sarah H; Stevenson, Ryan A; Wallace, Mark T

    2015-11-01

    Although sensory processing challenges have been noted since the first clinical descriptions of autism, it has taken until the release of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) in 2013 for sensory problems to be included as part of the core symptoms of autism spectrum disorder (ASD) in the diagnostic profile. Because sensory information forms the building blocks for higher-order social and cognitive functions, we argue that sensory processing is not only an additional piece of the puzzle, but rather a critical cornerstone for characterizing and understanding ASD. In this review we discuss what is currently known about sensory processing in ASD, how sensory function fits within contemporary models of ASD, and what is understood about the differences in the underlying neural processing of sensory and social communication observed between individuals with and without ASD. In addition to highlighting the sensory features associated with ASD, we also emphasize the importance of multisensory processing in building perceptual and cognitive representations, and how deficits in multisensory integration may also be a core characteristic of ASD.

  14. A Multi-Sensorial Hybrid Control for Robotic Manipulation in Human-Robot Workspaces

    PubMed Central

    Pomares, Jorge; Perea, Ivan; García, Gabriel J.; Jara, Carlos A.; Corrales, Juan A.; Torres, Fernando

    2011-01-01

    Autonomous manipulation in semi-structured environments where human operators can interact is an increasingly common task in robotic applications. This paper describes an intelligent multi-sensorial approach that solves this issue by providing a multi-robotic platform with a high degree of autonomy and the capability to perform complex tasks. The proposed sensorial system is composed of a hybrid visual servo control to efficiently guide the robot towards the object to be manipulated, an inertial motion capture system and an indoor localization system to avoid possible collisions between human operators and robots working in the same workspace, and a tactile sensor algorithm to correctly manipulate the object. The proposed controller employs the whole multi-sensorial system and combines the measurements of each one of the used sensors during two different phases considered in the robot task: a first phase where the robot approaches the object to be grasped, and a second phase of manipulation of the object. In both phases, the unexpected presence of humans is taken into account. This paper also presents the successful results obtained in several experimental setups which verify the validity of the proposed approach. PMID:22163729

  15. Semantic confusion regarding the development of multisensory integration: a practical solution

    PubMed Central

    Stein, Barry E.; Burr, David; Constantinidis, Christos; Laurienti, Paul J.; Meredith, M. Alex; Perrault, Thomas J.; Ramachandran, Ramnarayan; Röder, Brigitte; Rowland, Benjamin A.; Sathian, K.; Schroeder, Charles E.; Shams, Ladan; Stanford, Terrence R.; Wallace, Mark T.; Yu, Liping; Lewkowicz, David J.

    2011-01-01

    There is now a good deal of data from neurophysiological studies in animals and behavioral studies in human infants regarding the development of multisensory processing capabilities. Although the conclusions drawn from these different datasets sometimes appear to conflict, many of the differences are due to the use of different terms to mean the same thing and, more problematic, the use of similar terms to mean different things. Semantic issues are pervasive in the field and complicate communication among groups using different methods to study similar issues. Achieving clarity of communication among different investigative groups is essential for each to make full use of the findings of others, and an important step in this direction is to identify areas of semantic confusion. In this way investigators can be encouraged to use terms whose meaning and underlying assumptions are unambiguous because they are commonly accepted. Although this issue is of obvious importance to the large and very rapidly growing number of researchers working on multisensory processes, it is perhaps even more important to the non-cognoscenti. Those who wish to benefit from the scholarship in this field but are unfamiliar with the issues identified here are most likely to be confused by semantic inconsistencies. The current discussion attempts to document some of the more problematic of these, begin a discussion about the nature of the confusion and suggest some possible solutions. PMID:20584174

  16. Wireless Wearable Multisensory Suite and Real-Time Prediction of Obstructive Sleep Apnea Episodes

    PubMed Central

    Cheng, Changqing; Sangasoongsong, Akkarapol; Wongdhamma, Woranat; Bukkapatnam, Satish T. S.

    2013-01-01

    Obstructive sleep apnea (OSA) is a common sleep disorder found in 24% of adult men and 9% of adult women. Although continuous positive airway pressure (CPAP) has emerged as a standard therapy for OSA, a majority of patients are not tolerant to this treatment, largely because of the uncomfortable nasal air delivery during their sleep. Recent advances in wireless communication and advanced (“bigdata”) preditive analytics technologies offer radically new point-of-care treatment approaches for OSA episodes with unprecedented comfort and afforadability. We introduce a Dirichlet process-based mixture Gaussian process (DPMG) model to predict the onset of sleep apnea episodes based on analyzing complex cardiorespiratory signals gathered from a custom-designed wireless wearable multisensory suite. Extensive testing with signals from the multisensory suite as well as PhysioNet's OSA database suggests that the accuracy of offline OSA classification is 88%, and accuracy for predicting an OSA episode 1-min ahead is 83% and 3-min ahead is 77%. Such accurate prediction of an impending OSA episode can be used to adaptively adjust CPAP airflow (toward improving the patient's adherence) or the torso posture (e.g., minor chin adjustments to maintain steady levels of the airflow). PMID:27170854

  17. The multisensory basis of the self: From body to identity to others [Formula: see text].

    PubMed

    Tsakiris, Manos

    2017-04-01

    By grounding the self in the body, experimental psychology has taken the body as the starting point for a science of the self. One fundamental dimension of the bodily self is the sense of body ownership that refers to the special perceptual status of one's own body, the feeling that "my body" belongs to me. The primary aim of this review article is to highlight recent advances in the study of body ownership and our understanding of the underlying neurocognitive processes in three ways. I first consider how the sense of body ownership has been investigated and elucidated in the context of multisensory integration. Beyond exteroception, recent studies have considered how this exteroceptively driven sense of body ownership can be linked to the other side of embodiment, that of the unobservable, yet felt, interoceptive body, suggesting that these two sides of embodiment interact to provide a unifying bodily self. Lastly, the multisensorial understanding of the self has been shown to have implications for our understanding of social relationships, especially in the context of self-other boundaries. Taken together, these three research strands motivate a unified model of the self inspired by current predictive coding models.

  18. Plasticity in unimodal and multimodal brain areas reflects multisensory changes in self-face identification.

    PubMed

    Apps, Matthew A J; Tajadura-Jiménez, Ana; Sereno, Marty; Blanke, Olaf; Tsakiris, Manos

    2015-01-01

    Nothing provides as strong a sense of self as seeing one's face. Nevertheless, it remains unknown how the brain processes the sense of self during the multisensory experience of looking at one's face in a mirror. Synchronized visuo-tactile stimulation on one's own and another's face, an experience that is akin to looking in the mirror but seeing another's face, causes the illusory experience of ownership over the other person's face and changes in self-recognition. Here, we investigate the neural correlates of this enfacement illusion using fMRI. We examine activity in the human brain as participants experience tactile stimulation delivered to their face, while observing either temporally synchronous or asynchronous tactile stimulation delivered to another's face on either a specularly congruent or incongruent location. Activity in the multisensory right temporo-parietal junction, intraparietal sulcus, and the unimodal inferior occipital gyrus showed an interaction between the synchronicity and the congruency of the stimulation and varied with the self-reported strength of the illusory experience, which was recorded after each stimulation block. Our results highlight the important interplay between unimodal and multimodal information processing for self-face recognition, and elucidate the neurobiological basis for the plasticity required for identifying with our continuously changing visual appearance.

  19. Auditory, tactile, and multisensory cues facilitate search for dynamic visual stimuli.

    PubMed

    Ngo, Mary Kim; Spence, Charles

    2010-08-01

    Presenting an auditory or tactile cue in temporal synchrony with a change in the color of a visual target can facilitate participants' visual search performance. In the present study, we compared the magnitude of unimodal auditory, vibrotactile, and bimodal (i.e., multisensory) cuing benefits when the nonvisual cues were presented in temporal synchrony with the changing of the target's color (Experiments 1 and 2). The target (a horizontal or vertical line segment) was presented among a number of distractors (tilted line segments) that also changed color at various times. In Experiments 3 and 4, the cues were also made spatially informative with regard to the location of the visual target. The unimodal and bimodal cues gave rise to an equivalent (significant) facilitation of participants' visual search performance relative to a no-cue baseline condition. Making the unimodal auditory and vibrotactile cues spatially informative produced further performance improvements (on validly cued trials), as compared with cues that were spatially uninformative or otherwise spatially invalid. A final experiment was conducted in order to determine whether cue location (close to versus far from the visual display) would influence participants' visual search performance. Auditory cues presented close to the visual search display were found to produce significantly better performance than cues presented over headphones. Taken together, these results have implications for the design of nonvisual and multisensory warning signals used in complex visual displays.

  20. Spatiotemporal interplay between multisensory excitation and recruited inhibition in the lamprey optic tectum

    PubMed Central

    Grillner, Sten

    2016-01-01

    Animals integrate the different senses to facilitate event-detection for navigation in their environment. In vertebrates, the optic tectum (superior colliculus) commands gaze shifts by synaptic integration of different sensory modalities. Recent works suggest that tectum can elaborate gaze reorientation commands on its own, rather than merely acting as a relay from upstream/forebrain circuits to downstream premotor centers. We show that tectal circuits can perform multisensory computations independently and, hence, configure final motor commands. Single tectal neurons receive converging visual and electrosensory inputs, as investigated in the lamprey - a phylogenetically conserved vertebrate. When these two sensory inputs overlap in space and time, response enhancement of output neurons occurs locally in the tectum, whereas surrounding areas and temporally misaligned inputs are inhibited. Retinal and electrosensory afferents elicit local monosynaptic excitation, quickly followed by inhibition via recruitment of GABAergic interneurons. Multisensory inputs can thus regulate event-detection within tectum through local inhibition without forebrain control. DOI: http://dx.doi.org/10.7554/eLife.16472.001 PMID:27635636

  1. The multisensory basis of the self: From body to identity to others

    PubMed Central

    Tsakiris, Manos

    2017-01-01

    ABSTRACT By grounding the self in the body, experimental psychology has taken the body as the starting point for a science of the self. One fundamental dimension of the bodily self is the sense of body ownership that refers to the special perceptual status of one’s own body, the feeling that “my body” belongs to me. The primary aim of this review article is to highlight recent advances in the study of body ownership and our understanding of the underlying neurocognitive processes in three ways. I first consider how the sense of body ownership has been investigated and elucidated in the context of multisensory integration. Beyond exteroception, recent studies have considered how this exteroceptively driven sense of body ownership can be linked to the other side of embodiment, that of the unobservable, yet felt, interoceptive body, suggesting that these two sides of embodiment interact to provide a unifying bodily self. Lastly, the multisensorial understanding of the self has been shown to have implications for our understanding of social relationships, especially in the context of self–other boundaries. Taken together, these three research strands motivate a unified model of the self inspired by current predictive coding models. PMID:27100132

  2. Wireless Wearable Multisensory Suite and Real-Time Prediction of Obstructive Sleep Apnea Episodes.

    PubMed

    Le, Trung Q; Cheng, Changqing; Sangasoongsong, Akkarapol; Wongdhamma, Woranat; Bukkapatnam, Satish T S

    2013-01-01

    Obstructive sleep apnea (OSA) is a common sleep disorder found in 24% of adult men and 9% of adult women. Although continuous positive airway pressure (CPAP) has emerged as a standard therapy for OSA, a majority of patients are not tolerant to this treatment, largely because of the uncomfortable nasal air delivery during their sleep. Recent advances in wireless communication and advanced ("bigdata") preditive analytics technologies offer radically new point-of-care treatment approaches for OSA episodes with unprecedented comfort and afforadability. We introduce a Dirichlet process-based mixture Gaussian process (DPMG) model to predict the onset of sleep apnea episodes based on analyzing complex cardiorespiratory signals gathered from a custom-designed wireless wearable multisensory suite. Extensive testing with signals from the multisensory suite as well as PhysioNet's OSA database suggests that the accuracy of offline OSA classification is 88%, and accuracy for predicting an OSA episode 1-min ahead is 83% and 3-min ahead is 77%. Such accurate prediction of an impending OSA episode can be used to adaptively adjust CPAP airflow (toward improving the patient's adherence) or the torso posture (e.g., minor chin adjustments to maintain steady levels of the airflow).

  3. Multisensory brand search: How the meaning of sounds guides consumers' visual attention.

    PubMed

    Knoeferle, Klemens M; Knoeferle, Pia; Velasco, Carlos; Spence, Charles

    2016-06-01

    Building on models of crossmodal attention, the present research proposes that brand search is inherently multisensory, in that the consumers' visual search for a specific brand can be facilitated by semantically related stimuli that are presented in another sensory modality. A series of 5 experiments demonstrates that the presentation of spatially nonpredictive auditory stimuli associated with products (e.g., usage sounds or product-related jingles) can crossmodally facilitate consumers' visual search for, and selection of, products. Eye-tracking data (Experiment 2) revealed that the crossmodal effect of auditory cues on visual search manifested itself not only in RTs, but also in the earliest stages of visual attentional processing, thus suggesting that the semantic information embedded within sounds can modulate the perceptual saliency of the target products' visual representations. Crossmodal facilitation was even observed for newly learnt associations between unfamiliar brands and sonic logos, implicating multisensory short-term learning in establishing audiovisual semantic associations. The facilitation effect was stronger when searching complex rather than simple visual displays, thus suggesting a modulatory role of perceptual load. (PsycINFO Database Record

  4. Behavioral, Perceptual, and Neural Alterations in Sensory and Multisensory Function in Autism Spectrum Disorder

    PubMed Central

    Baum, Sarah H.; Stevenson, Ryan A.; Wallace, Mark T.

    2015-01-01

    Although sensory processing challenges have been noted since the first clinical descriptions of autism, it has taken until the release of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) in 2013 for sensory problems to be included as part of the core symptoms of autism spectrum disorder (ASD) in the diagnostic profile. Because sensory information forms the building blocks for higher-order social and cognitive functions, we argue that sensory processing is not only an additional piece of the puzzle, but rather a critical cornerstone for characterizing and understanding ASD. In this review we discuss what is currently known about sensory processing in ASD, how sensory function fits within contemporary models of ASD, and what is understood about the differences in the underlying neural processing of sensory and social communication observed between individuals with and without ASD. In addition to highlighting the sensory features associated with ASD, we also emphasize the importance of multisensory processing in building perceptual and cognitive representations, and how deficits in multisensory integration may also be a core characteristic of ASD. PMID:26455789

  5. Engineering the development of systems for multisensory monitoring and activity interpretation

    NASA Astrophysics Data System (ADS)

    Gascueña, José Manuel; Castillo, José Carlos; Navarro, Elena; Fernández-Caballero, Antonio

    2014-04-01

    Multisensory monitoring and activity interpretation systems are being increasingly used as a suitable means to detect situations and make decisions in an intelligent manner. However, there is a lack of formalised processes that guide the stakeholders in their development. Most of the current proposals focus on the implementation and evaluation of low-level algorithms. In order to overcome this lack, a process called INT3-SDP that guides stakeholders in the development of systems capable of carrying out multisensory monitoring and INTerpretation of behaviours and situations for an INTelligent INTervention in complex and dynamic environments is described in this paper. In this work, it is described how INT3-SDP provides the analysts with the guidelines and models necessary for the description of the environment to be monitored and the sensors to be installed, as well as in the implementation of the software components that perform the monitoring and activity interpretation tasks. Moreover, a case study is also presented in order to illustrate how INT3-SDP is put into practice.

  6. The influence of temporal asynchrony on multisensory integration in the processing of asynchronous audio-visual stimuli of real-world events: an event-related potential study.

    PubMed

    Liu, B; Jin, Z; Wang, Z; Gong, C

    2011-03-10

    In this study, we manipulated the temporal asynchrony between auditory and visual inputs, and contrasted event-related potentials (ERPs) evoked by multisensory stimuli with the summation of the ERPs evoked by unisensory-auditory (A) and unisensory-visual (V) stimuli with the same temporal asynchrony. Our goal was to investigate the influence of temporal asynchrony on multisensory integration. In our experiment, the auditory and visual inputs in the multisensory stimuli had a stimulus onset asynchrony (SOA) of -300 ms, 0 ms, or 300 ms. The results suggested that when the auditory and visual inputs were synchronous, multisensory integrations would occur in the time windows of 110-160 ms, 210-250 ms and 300-350 ms after auditory onset. When the auditory onset preceded the critical action onset by 300 ms, multisensory integrations were involved in the time windows of 110-160 ms and 300-350 ms after auditory onset. When the critical action onset preceded the auditory onset by 300 ms, multisensory integrations would occur in the time windows of 110-160 ms, 210-250 ms, 290-320 ms and 350-400 ms after auditory onset. In addition, in the time windows of 110-160 ms and 210-250 ms, the integrations were stronger when the auditory and visual inputs were synchronous, and in the time window of 250-400 ms, multisensory integrations would be different as the SOAs were different. It was suggested that multisensory integration would occur regardless of the asynchrony between auditory and visual inputs, and multisensory integration could be influenced by temporal asynchrony.

  7. Studying Multisensory Processing and Its Role in the Representation of Space through Pathological and Physiological Crossmodal Extinction.

    PubMed

    Jacobs, Stéphane; Brozzoli, Claudio; Hadj-Bouziane, Fadila; Meunier, Martine; Farnè, Alessandro

    2011-01-01

    The study of crossmodal extinction has brought a considerable contribution to our understanding of how the integration of stimuli perceived in multiple sensory modalities is used by the nervous system to build coherent representations of the space that directly surrounds us. Indeed, by revealing interferences between stimuli in a disturbed system, extinction provides an invaluable opportunity to investigate the interactions that normally exist between those stimuli in an intact system. Here, we first review studies on pathological crossmodal extinction, from the original demonstration of its existence, to its role in the exploration of the multisensory neural representation of space and the current theoretical accounts proposed to explain the mechanisms involved in extinction and multisensory competition. Then, in the second part of this paper, we report recent findings showing that physiological multisensory competition phenomena resembling clinical crossmodal extinction exist in the healthy brain. We propose that the development of a physiological model of sensory competition is fundamental to deepen our understanding of the cerebral mechanisms of multisensory perception and integration. In addition, a similar approach to develop a model of physiological sensory competition in non-human primates should allow combining functional neuroimaging with more invasive techniques, such as transient focal lesions, in order to bridge the gap between works done in the two species and at different levels of analysis.

  8. The Effects of a Summer Reading Program Using Simultaneous Multisensory Instruction of Language Arts on Reading Proficiency

    ERIC Educational Resources Information Center

    Magpuri-Lavell, Theresa; Paige, David; Williams, Rosemary; Akins, Kristia; Cameron, Molly

    2014-01-01

    The present study examined the impact of the Simultaneous Multisensory Institute for Language Arts (SMILA) approach on the reading proficiency of 39 students between the ages of 7-11 participating in a summer reading program. The summer reading clinic draws students from the surrounding community which is located in a large urban district in the…

  9. Perception of the multisensory coherence of fluent audiovisual speech in infancy: its emergence and the role of experience.

    PubMed

    Lewkowicz, David J; Minar, Nicholas J; Tift, Amy H; Brandon, Melissa

    2015-02-01

    To investigate the developmental emergence of the perception of the multisensory coherence of native and non-native audiovisual fluent speech, we tested 4-, 8- to 10-, and 12- to 14-month-old English-learning infants. Infants first viewed two identical female faces articulating two different monologues in silence and then in the presence of an audible monologue that matched the visible articulations of one of the faces. Neither the 4-month-old nor 8- to 10-month-old infants exhibited audiovisual matching in that they did not look longer at the matching monologue. In contrast, the 12- to 14-month-old infants exhibited matching and, consistent with the emergence of perceptual expertise for the native language, perceived the multisensory coherence of native-language monologues earlier in the test trials than that of non-native language monologues. Moreover, the matching of native audible and visible speech streams observed in the 12- to 14-month-olds did not depend on audiovisual synchrony, whereas the matching of non-native audible and visible speech streams did depend on synchrony. Overall, the current findings indicate that the perception of the multisensory coherence of fluent audiovisual speech emerges late in infancy, that audiovisual synchrony cues are more important in the perception of the multisensory coherence of non-native speech than that of native audiovisual speech, and that the emergence of this skill most likely is affected by perceptual narrowing.

  10. Uni- and crossmodal refractory period effects of event-related potentials provide insights into the development of multisensory processing

    PubMed Central

    Johannsen, Jessika; Röder, Brigitte

    2014-01-01

    To assess uni- and multisensory development in humans, uni- and crossmodal event-related potential (ERP) refractory period effects were investigated. Forty-one children from 4 to 12 years of age and 15 young adults performed a bimodal oddball task with frequent and rare visual and auditory stimuli presented with two different interstimulus intervals (ISIs). Amplitudes of the visual and auditory ERPs were modulated as a function of the age of the participants, the modality of the preceding stimulus (same vs. different) and the preceding ISI (1000 or 2000 ms). While unimodal refractory period effects were observed in all age groups, crossmodal refractory period effects differed among age groups. Early crossmodal interactions (<150 ms) existing in the youngest age group (4–6 years) disappeared, while later crossmodal interactions (>150 ms) emerged with a parietal topography in older children and adults. Our results are compatible with the intersensory differentiation and the multisensory perceptual narrowing approach of multisensory development. Moreover, our data suggest that uni- and multisensory development run in parallel with unimodal development leading. PMID:25120454

  11. Studying Multisensory Processing and Its Role in the Representation of Space through Pathological and Physiological Crossmodal Extinction

    PubMed Central

    Jacobs, Stéphane; Brozzoli, Claudio; Hadj-Bouziane, Fadila; Meunier, Martine; Farnè, Alessandro

    2011-01-01

    The study of crossmodal extinction has brought a considerable contribution to our understanding of how the integration of stimuli perceived in multiple sensory modalities is used by the nervous system to build coherent representations of the space that directly surrounds us. Indeed, by revealing interferences between stimuli in a disturbed system, extinction provides an invaluable opportunity to investigate the interactions that normally exist between those stimuli in an intact system. Here, we first review studies on pathological crossmodal extinction, from the original demonstration of its existence, to its role in the exploration of the multisensory neural representation of space and the current theoretical accounts proposed to explain the mechanisms involved in extinction and multisensory competition. Then, in the second part of this paper, we report recent findings showing that physiological multisensory competition phenomena resembling clinical crossmodal extinction exist in the healthy brain. We propose that the development of a physiological model of sensory competition is fundamental to deepen our understanding of the cerebral mechanisms of multisensory perception and integration. In addition, a similar approach to develop a model of physiological sensory competition in non-human primates should allow combining functional neuroimaging with more invasive techniques, such as transient focal lesions, in order to bridge the gap between works done in the two species and at different levels of analysis. PMID:21687458

  12. Perception of the Multisensory Coherence of Fluent Audiovisual Speech in Infancy: Its Emergence & the Role of Experience

    PubMed Central

    Lewkowicz, David J.; Minar, Nicholas J.; Tift, Amy H.; Brandon, Melissa

    2014-01-01

    To investigate the developmental emergence of the ability to perceive the multisensory coherence of native and non-native audiovisual fluent speech, we tested 4-, 8–10, and 12–14 month-old English-learning infants. Infants first viewed two identical female faces articulating two different monologues in silence and then in the presence of an audible monologue that matched the visible articulations of one of the faces. Neither the 4-month-old nor the 8–10 month-old infants exhibited audio-visual matching in that neither group exhibited greater looking at the matching monologue. In contrast, the 12–14 month-old infants exhibited matching and, consistent with the emergence of perceptual expertise for the native language, they perceived the multisensory coherence of native-language monologues earlier in the test trials than of non-native language monologues. Moreover, the matching of native audible and visible speech streams observed in the 12–14 month olds did not depend on audio-visual synchrony whereas the matching of non-native audible and visible speech streams did depend on synchrony. Overall, the current findings indicate that the perception of the multisensory coherence of fluent audiovisual speech emerges late in infancy, that audio-visual synchrony cues are more important in the perception of the multisensory coherence of non-native than native audiovisual speech, and that the emergence of this skill most likely is affected by perceptual narrowing. PMID:25462038

  13. Direct Instruction + UDL = Access for Diverse Learners: How to Plan and Implement an Effective Multisensory Spelling Lesson

    ERIC Educational Resources Information Center

    Metcalf, Debbie; Evans, Chan; Flynn, Hayley K.; Williams, Jennifer B.

    2009-01-01

    This article describes a lesson plan model that applies principles of universal design for learning (UDL) and multisensory learning centers to the framework of a traditional direct instruction spelling lesson for elementary students with learning, social, and attention problems. It reviews essential components of UDL and demonstrates how to…

  14. The Use of 'Snoezelen' as Multisensory Stimulation with People with Intellectual Disabilities: A Review of the Research.

    ERIC Educational Resources Information Center

    Hogg, James; Cavet, Judith; Lambe, Loretto; Smeddle, Mary

    2001-01-01

    A research review on the use of Snoezelen (multisensory training) with people with mental retardation demonstrates a wide range of positive outcomes, though there is little evidence of generalization even to the immediate post-Snoezelen environment. The issue of staff attitudes and the place of Snoezelen in facilitating positive interactions is…

  15. Formin' actin in the nucleus.

    PubMed

    Baarlink, Christian; Grosse, Robert

    2014-01-01

    Many if not most proteins can, under certain conditions, change cellular compartments, such as, for example, shuttling from the cytoplasm to the nucleus. Thus, many proteins may exert functions in various and very different subcellular locations, depending on the signaling context. A large amount of actin regulatory proteins has been detected in the mammalian cell nucleus, although their potential roles are much debated and are just beginning to emerge. Recently, members of the formin family of actin nucleators were also reported to dynamically localize to the nuclear environment. Here we discuss our findings that specific diaphanous-related formins can promote nuclear actin assembly in a signal-dependent manner.

  16. Functionalized active-nucleus complex sensor

    DOEpatents

    Pines, Alexander; Wemmer, David E.; Spence, Megan; Rubin, Seth

    2003-11-25

    A functionalized active-nucleus complex sensor that selectively associates with one or more target species, and a method for assaying and screening for one or a plurality of target species utilizing one or a plurality of functionalized active-nucleus complexes with at least two of the functionalized active-nucleus complexes having an attraction affinity to different corresponding target species. The functionalized active-nucleus complex has an active-nucleus and a targeting carrier. The method involves functionalizing an active-nucleus, for each functionalized active-nucleus complex, by incorporating the active-nucleus into a macromolucular or molecular complex that is capable of binding one of the target species and then bringing the macromolecular or molecular complexes into contact with the target species and detecting the occurrence of or change in a nuclear magnetic resonance signal from each of the active-nuclei in each of the functionalized active-nucleus complexes.

  17. Modeling development of natural multi-sensory integration using neural self-organisation and probabilistic population codes

    NASA Astrophysics Data System (ADS)

    Bauer, Johannes; Dávila-Chacón, Jorge; Wermter, Stefan

    2015-10-01

    Humans and other animals have been shown to perform near-optimally in multi-sensory integration tasks. Probabilistic population codes (PPCs) have been proposed as a mechanism by which optimal integration can be accomplished. Previous approaches have focussed on how neural networks might produce PPCs from sensory input or perform calculations using them, like combining multiple PPCs. Less attention has been given to the question of how the necessary organisation of neurons can arise and how the required knowledge about the input statistics can be learned. In this paper, we propose a model of learning multi-sensory integration based on an unsupervised learning algorithm in which an artificial neural network learns the noise characteristics of each of its sources of input. Our algorithm borrows from the self-organising map the ability to learn latent-variable models of the input and extends it to learning to produce a PPC approximating a probability density function over the latent variable behind its (noisy) input. The neurons in our network are only required to perform simple calculations and we make few assumptions about input noise properties and tuning functions. We report on a neurorobotic experiment in which we apply our algorithm to multi-sensory integration in a humanoid robot to demonstrate its effectiveness and compare it to human multi-sensory integration on the behavioural level. We also show in simulations that our algorithm performs near-optimally under certain plausible conditions, and that it reproduces important aspects of natural multi-sensory integration on the neural level.

  18. Multisensory representation of frequency across audition and touch: High density electrical mapping reveals early sensory-perceptual coupling

    PubMed Central

    Butler, John S.; Foxe, John J.; Fiebelkorn, Ian C.; Mercier, Manuel; Molholm, Sophie

    2013-01-01

    The frequency of environmental vibrations is sampled by two of the major sensory systems, audition and touch, notwithstanding that these signals are transduced through very different physical media and entirely separate sensory epithelia. Psychophysical studies have shown that manipulating frequency in audition or touch can have a significant cross-sensory impact on perceived frequency in the other sensory system, pointing to intimate links between these senses during computation of frequency. In this regard, the frequency of a vibratory event can be thought of as a multisensory perceptual construct. In turn, electrophysiological studies point to temporally early multisensory interactions that occur in hierarchically early sensory regions where convergent inputs from the auditory and somatosensory systems are to be found. A key question pertains to the level of processing at which the multisensory integration of featural information such as frequency occurs. Do the sensory systems calculate frequency independently before this information is combined, or is this feature calculated in an integrated fashion during pre-attentive sensory processing? The well-characterized mismatch negativity, an electrophysiological response that indexes pre-attentive detection of a change within the context of a regular pattern of stimulation, served as our dependent measure. High-density electrophysiological recordings were made in humans while they were presented with separate blocks of somatosensory, auditory, and audio-somatosensory “standards” and “deviants”, where the deviant differed in frequency. Multisensory effects were identified beginning at ~200ms, with the multisensory MMN significantly different from the sum of the unisensory MMNs. This provides compelling evidence for preattentive coupling between the somatosensory and auditory channels in the cortical representation of frequency. PMID:23115172

  19. The role of the parietal cortex in multisensory and response integration: evidence from transcranial direct current stimulation (tDCS).

    PubMed

    Zmigrod, Sharon

    2014-01-01

    The question of how the brain forms unified representations from multisensory data that are processed in distinct cortical regions is known in the literature as 'the binding problem'. In the last decade, several studies have suggested possible neural mechanisms and brain regions that might be involved in integration processes. One of the brain regions that is implicated with multisensory perception is the posterior parietal cortex (PPC). Evidence from patients with parietal lesions suggests the involvement of the PPC in coherent perception. Here, we investigated the role of the PPC in multisensory feature integration through experimental manipulation of non-invasive brain stimulation with healthy participants using transcranial direct current stimulation (tDCS). In different sessions, healthy participants received anodal, cathodal, or sham stimulation (2 mA, 20 min) over the right PPC while performing an audio-visual event-file task. The results underscore two interesting observations. Firstly, there was a significant difference in integration effects between features from different modalities in the anodal stimulation compared to sham, suggesting interference of the multisensory integration processes during the brain stimulation. And secondly, after anodal stimulation, the unattended feature became more likely to be integrated with the response feature compared to the other conditions, presumably through an interference of attentional processes. Hence, these findings emphasize the role of the right PPC in multisensory integration. Furthermore, from a methodological perspective, tDCS can be used as an experimental tool by creating a temporary, reversible disruption in cognitive processes in order to explore the mechanisms underlying cognitive functions.

  20. Higgs and Particle Production in Nucleus-Nucleus Collisions

    NASA Astrophysics Data System (ADS)

    Liu, Zhe

    We apply a diagrammatic approach to study Higgs boson, a color-neutral heavy particle, pro- duction in nucleus-nucleus collisions in the saturation framework without quantum evolution. We assume the strong coupling constant much smaller than one. Due to the heavy mass and colorless nature of Higgs particle, final state interactions are absent in our calculation. In order to treat the two nuclei dynamically symmetric, we use the Coulomb gauge which gives the appropriate light cone gauge for each nucleus. To further eliminate initial state interactions we choose specific prescriptions in the light cone propagators. We start the calculation from only two nucleons in each nucleus and then demonstrate how to generalize the calculation to higher orders diagrammatically. We simplify the diagrams by the Slavnov-Taylor-Ward identities. The resulting cross section is factorized into a product of two Weizsacker-Williams gluon distributions of the two nuclei when the transverse momentum of the produced scalar particle is around the saturation momentum. To our knowledge this is the first process where an exact analytic formula has been formed for a physical process, involving momenta on the order of the saturation momentum, in nucleus-nucleus collisions in the quasi-classical approximation. Since we have performed the calculation in an unconventional gauge choice, we further confirm our results in Feynman gauge where the Weizsacker-Williams gluon distribution is interpreted as a transverse momentum broadening of a hard gluons traversing a nuclear medium. The transverse momentum factorization manifests itself in light cone gauge but not so clearly in Feynman gauge. In saturation physics there are two different unintegrated gluon distributions usually encountered in the literature: the Weizsacker-Williams gluon distribution and the dipole gluon distribution. The first gluon distribution is constructed by solving classical Yang-Mills equation of motion in the Mc

  1. New multifunctional surfactants from natural phenolic acids.

    PubMed

    Centini, Marisanna; Rossato, Maria Sole; Sega, Alessandro; Buonocore, Anna; Stefanoni, Sara; Anselmi, Cecilia

    2012-01-11

    Several new multifunctional molecules derived from natural sources such as amino acids and hydroxycinnamic acids were synthesized. They exhibit various activities such as emulsifying, UV-protecting, and radical scavenging, thereby conforming to the latest requirements for cosmetic ingredients. The synthesis comprises only a few steps: (i) the amino acid, the acid groups of which are protected by esterification, is coupled with ferulic or caffeic acid; (ii) the p-hydroxyl group of the cinnamic derivative reacts with dodecyl bromide in the presence of potassium carbonate (the resulting compounds are highly lipophilic and tested as water/oil (W/O) emulsifiers); (iii) these molecules, by deprotonating the acid groups of the amino acids, with successive salification, are more hydrophilic, with stronger O/W emulsifying properties. The new multifunctional surfactants might prove useful for the treatment of multiple skin conditions, including loss of cellular antioxidants, damage from free radicals, damage from UV, and others.

  2. Emerging Multifunctional Metal-Organic Framework Materials.

    PubMed

    Li, Bin; Wen, Hui-Min; Cui, Yuanjing; Zhou, Wei; Qian, Guodong; Chen, Banglin

    2016-10-01

    Metal-organic frameworks (MOFs), also known as coordination polymers, represent an interesting type of solid crystalline materials that can be straightforwardly self-assembled through the coordination of metal ions/clusters with organic linkers. Owing to the modular nature and mild conditions of MOF synthesis, the porosities of MOF materials can be systematically tuned by judicious selection of molecular building blocks, and a variety of functional sites/groups can be introduced into metal ions/clusters, organic linkers, or pore spaces through pre-designing or post-synthetic approaches. These unique advantages enable MOFs to be used as a highly versatile and tunable platform for exploring multifunctional MOF materials. Here, the bright potential of MOF materials as emerging multifunctional materials is highlighted in some of the most important applications for gas storage and separation, optical, electric and magnetic materials, chemical sensing, catalysis, and biomedicine.

  3. Common and distinct brain regions processing multisensory bodily signals for peripersonal space and body ownership.

    PubMed

    Grivaz, Petr; Blanke, Olaf; Serino, Andrea

    2017-02-15

    We take the feeling that our body belongs to us for granted. However, recent research has shown that it is possible to alter the subjective sensation of body ownership (BO) by manipulating multisensory bodily inputs. Several frontal and parietal regions are known to specifically process multisensory cues presented close to the body, i.e., within the peripersonal space (PPS). It has been proposed that these PPS fronto-parietal regions also underlie BO. However, most previous studies investigated the brain mechanisms of either BO or of PPS processing separately and by using a variety of paradigms. Here, we conducted an extensive meta-analysis of functional neuroimaging studies to investigate PPS and BO processing in humans in order to: a) assess quantitatively where each one of these functions was individually processed in the brain; b) identify whether and where these processes shared common or engaged distinct brain mechanisms; c) characterize these areas in terms of whole-brain co-activation networks and functions, respectively. We identified (i) a bilateral PPS network including superior parietal, temporo-parietal and ventral premotor regions and (ii) a BO network including posterior parietal cortex (right intraparietal sulcus, IPS; and left IPS and superior parietal lobule, SPL), right ventral premotor cortex, and the left anterior insula. Co-activation maps related to both PPS and BO encompassed largely overlapping fronto-parietal networks, but whereas the PPS network was more frequently associated with sensorimotor tasks, the BO network was rather associated with attention and awareness tasks. Finally, the conjunction analysis showed that (iii) PPS and BO tasks anatomically overlapped only in two clusters located in the left parietal cortex (dorsally at the intersection between the SPL, the IPS and area 2 and ventrally between areas 2 and IPS). Distinct activations were located for PPS at the temporo-parietal junction and for BO in the anterior insula. These

  4. Multiscale/Multifunctional Probabilistic Composite Fatigue

    NASA Technical Reports Server (NTRS)

    Chamis, Christos C.

    2010-01-01

    A multilevel (multiscale/multifunctional) evaluation is demonstrated by applying it to three different sample problems. These problems include the probabilistic evaluation of a space shuttle main engine blade, an engine rotor and an aircraft wing. The results demonstrate that the blade will fail at the highest probability path, the engine two-stage rotor will fail by fracture at the rim and the aircraft wing will fail at 109 fatigue cycles with a probability of 0.9967.

  5. A Multifunctional Coating for Autonomous Corrosion Control

    NASA Technical Reports Server (NTRS)

    Calle, Luz M.; Li, Wenyan; Buhrow, Jerry W.; Jolley, Scott t.

    2011-01-01

    Nearly all metals and their alloys are subject to corrosion that causes them to lose their structural integrity or other critical functionality. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to indicate it and control it. The multi-functionality of the coating is based on microencapsulation technology specifically designed for corrosion control applications. This design has, in addition to all the advantages of existing microcapsulation designs, the corrosion controlled release function that triggers the delivery of corrosion indicators and inhibitors on demand, only when and where needed. Microencapsulation of self-healing agents for autonomous repair of mechanical damage to the coating is also being pursued. Corrosion indicators, corrosion inhibitors, as well as self-healing agents, have been encapsulated and dispersed into several paint systems to test the corrosion detection, inhibition, and self-healing properties of the coating. Key words: Corrosion, coating, autonomous corrosion control, corrosion indication, corrosion inhibition, self-healing coating, smart coating, multifunctional coating, microencapsulation.

  6. From polymer latexes to multifunctional liquid marbles.

    PubMed

    Fernandes, Ana M; Mantione, Daniele; Gracia, Raquel; Leiza, Jose R; Paulis, Maria; Mecerreyes, David

    2015-02-25

    A simple method to prepare multifunctional liquid marbles and dry water with magnetic, color, and fluorescent properties is presented. Multifunctional liquid marbles were prepared by encapsulation of water droplets using flocculated polymer latexes. First, the emulsion polymerization reaction of polystyrene and poly(benzyl methacrylate) was carried out using cheap and commercially available cationic surfactants. Subsequently, flocculation of the latex was provoked by an anion-exchange reaction of the cationic surfactant by the addition of lithium bis(trifluoromethanesulfonyl)imide salt. The flocculated polymer latex was filtered and dried, leading to very hydrophobic micronanoparticulated powders. These powders showed a great ability to stabilize the air/water interface. Stable liquid marbles were obtained by rolling water droplets onto the hydrophobic powders previously prepared. The use of very small polystyrene nanoparticles led us to the preparation of very stable and the biggest known liquid marbles up to 2.5 mL of water. Furthermore, the introduction of fluorescent comonomer dyes into the polymer powders allowed us to obtain new morphological images and new knowledge about the structure of liquid marbles by confocal microscopy. Furthermore, the introduction of magnetic nanoparticles into the polymer latex led to magnetic responsive liquid marbles, where the iron oxide nanoparticles are protected within a polymer. Altogether this method represents an accessible and general platform for the preparation of multifunctional liquid marbles and dry water, which may contribute to extending of their actual range of applications.

  7. Brain and Language: Evidence for Neural Multifunctionality

    PubMed Central

    Cahana-Amitay, Dalia; Albert, Martin L.

    2014-01-01

    This review paper presents converging evidence from studies of brain damage and longitudinal studies of language in aging which supports the following thesis: the neural basis of language can best be understood by the concept of neural multifunctionality. In this paper the term “neural multifunctionality” refers to incorporation of nonlinguistic functions into language models of the intact brain, reflecting a multifunctional perspective whereby a constant and dynamic interaction exists among neural networks subserving cognitive, affective, and praxic functions with neural networks specialized for lexical retrieval, sentence comprehension, and discourse processing, giving rise to language as we know it. By way of example, we consider effects of executive system functions on aspects of semantic processing among persons with and without aphasia, as well as the interaction of executive and language functions among older adults. We conclude by indicating how this multifunctional view of brain-language relations extends to the realm of language recovery from aphasia, where evidence of the influence of nonlinguistic factors on the reshaping of neural circuitry for aphasia rehabilitation is clearly emerging. PMID:25009368

  8. Thick-walled carbon composite multifunctional structures

    NASA Astrophysics Data System (ADS)

    Haake, John M.; Jacobs, Jack H.; McIlroy, Bruce E.

    1997-06-01

    Satellite programs are moving in the direction of smaller and lighter structures. Technological advances have permitted more sophisticated equipment to be consolidated into compact spaces. Micro-satellites, between 10 and 100 kg, will incorporate micro-electric devices into the lay-up of the satellite structure. These structures will be designed to carry load, provide thermal control, enhance damping, and include integrated passive electronics. These multifunctional structures offer lighter weight, reduced volume, and a 'smarter' overall package for incorporation of sensors, electronics, fiber optics, powered appendages or active components. McDonnell Douglas Corporation (MDC) has applied technology from the synthesis and processing of intelligent cost effective structures (SPICES) and independent research and development (IRAD) programs to the modular instrument support system (MISS) for multifunctional space structures and micro-satellites. The SPICES program was funded by the Defense Advanced Research Projects Agency (DARPA) to develop affordable manufacturing processes for smart materials to be used in vibration control, and the MISS program was funded by NASA-Langley. The MISS program was conceived to develop concepts and techniques to make connections between different multifunctional structures. MDA fabricated a trapezoidal carbon composite structure out of IM7/977-3 tape prepreg. Flex circuits, thermal and optical conduits were embedded to realize a utility modular connector. These provide electrical, thermal, optical and mechanical connections between micro- satellite components. A quick disconnect mount was also developed to accommodate a variety of devices such as solar arrays, power sources, thermal transfer and vibration control modules.

  9. Single nucleon emission in relativistic nucleus-nucleus reactions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Townsend, Lawrence W.

    1992-01-01

    Significant discrepancies between theory and experiment have previously been noted for nucleon emission via electromagnetic processes in relativistic nucleus-nucleus collisions. The present work investigates the hypothesis that these discrepancies have arisen due to uncertainties about how to deduce the experimental electromagnetic cross section from the total measured cross section. An optical-model calculation of single neutron removal is added to electromagnetic cross sections and compared to the total experimental cross sections. Good agreement is found thereby resolving some of the earlier noted discrepancies. A detailed comparison to the recent work of Benesh, Cook, and Vary is made for both the impact parameter and the nuclear cross section. Good agreement is obtained giving an independent confirmation of the parameterized formulas developed by those authors.

  10. Analysis of relativistic nucleus-nucleus interactions in emulsion chambers

    NASA Technical Reports Server (NTRS)

    Mcguire, Stephen C.

    1987-01-01

    The development of a computer-assisted method is reported for the determination of the angular distribution data for secondary particles produced in relativistic nucleus-nucleus collisions in emulsions. The method is applied to emulsion detectors that were placed in a constant, uniform magnetic field and exposed to beams of 60 and 200 GeV/nucleon O-16 ions at the Super Proton Synchrotron (SPS) of the European Center for Nuclear Research (CERN). Linear regression analysis is used to determine the azimuthal and polar emission angles from measured track coordinate data. The software, written in BASIC, is designed to be machine independent, and adaptable to an automated system for acquiring the track coordinates. The fitting algorithm is deterministic, and takes into account the experimental uncertainty in the measured points. Further, a procedure for using the track data to estimate the linear momenta of the charged particles observed in the detectors is included.

  11. Dynamical nucleus-nucleus potential at short distances

    SciTech Connect

    Jiang Yongying; Wang Ning; Li Zhuxia; Scheid, Werner

    2010-04-15

    The dynamical nucleus-nucleus potentials for fusion reactions {sup 40}Ca+{sup 40}Ca, {sup 48}Ca+{sup 208}Pb, and {sup 126}Sn+{sup 130}Te are studied with the improved quantum molecular dynamics model together with the extended Thomas-Fermi approximation for the kinetic energies of nuclei. The obtained fusion barrier for {sup 40}Ca+{sup 40}Ca is in good agreement with the extracted fusion barrier from the measured fusion excitation function, and the depths of the fusion pockets are close to the results of time-dependent Hartree-Fock calculations. The energy dependence of the fusion barrier is also investigated. The fusion pocket becomes shallow for a heavy fusion system and almost disappears for heavy nearly symmetric systems, and the obtained potential at short distances is higher than the adiabatic potential.

  12. Azimuthal correlation and collective behavior in nucleus-nucleus collisions

    SciTech Connect

    Mali, P.; Mukhopadhyay, A. Sarkar, S.; Singh, G.

    2015-03-15

    Various flow effects of nuclear and hadronic origin are investigated in nucleus-nucleus collisions. Nuclear emulsion data collected from {sup 84}Kr + Ag/Br interaction at an incident energy of 1.52 GeV per nucleon and from {sup 28}Si + Ag/Br interaction at an incident energy of 14.5 GeV per nucleon are used in the investigation. The transverse momentum distribution and the flow angle analysis show that collective behavior, like a bounce-off effect of the projectile spectators and a sidesplash effect of the target spectators, are present in our event samples. From an azimuthal angle analysis of the data we also see a direct flow of the projectile fragments and of the produced charged particles. On the other hand, for both data samples the target fragments exhibit a reverse flow, while the projectile fragments exhibit an elliptic flow. Relevant flow parameters are measured.

  13. Design of a Multisensory Probe for Measuring Carbon Cycle Processes in Aqueous Subterranean Environments

    SciTech Connect

    McIntyre, Timothy J; Kisner, Roger; Woodworth, Ken; Lenarduzzi, Roberto; Frank, Steven Shane; McKnight, Timothy E

    2015-01-01

    The global carbon cycle describes the exchange of carbon between the atmosphere, terrestrial vegetation, oceans, and soil. Mechanisms involving carbon in sub-terrestrial ecosystems and their impact on climate are not well understood. This lack of understanding limits current climate models and prevents accurate soil-carbon storage predications for future climate conditions. To address the lack of instrumentation for conducting high fidelity measurements of appropriate parameters in the field, a multi-sensory probe using a mix of optical, fiber optic, and electronic technologies to measure CO2, temperature, dissolved oxygen, redox potential, and water level in subsurface environments has been developed. Details of the design, fabrication and laboratory performance verification are presented. Use cases and the anticipated impacts of such measurements on climate models are discussed.

  14. Multisensory systems integration for high-performance motor control in flies.

    PubMed

    Frye, Mark A

    2010-06-01

    Engineered tracking systems 'fuse' data from disparate sensor platforms, such as radar and video, to synthesize information that is more reliable than any single input. The mammalian brain registers visual and auditory inputs to directionally localize an interesting environmental feature. For a fly, sensory perception is challenged by the extreme performance demands of high speed flight. Yet even a fruit fly can robustly track a fragmented odor plume through varying visual environments, outperforming any human engineered robot. Flies integrate disparate modalities, such as vision and olfaction, which are neither related by spatiotemporal spectra nor processed by registered neural tissue maps. Thus, the fly is motivating new conceptual frameworks for how low-level multisensory circuits and functional algorithms produce high-performance motor control.

  15. Neurophysiological indices of atypical auditory processing and multisensory integration are associated with symptom severity in autism.

    PubMed

    Brandwein, Alice B; Foxe, John J; Butler, John S; Frey, Hans-Peter; Bates, Juliana C; Shulman, Lisa H; Molholm, Sophie

    2015-01-01

    Atypical processing and integration of sensory inputs are hypothesized to play a role in unusual sensory reactions and social-cognitive deficits in autism spectrum disorder (ASD). Reports on the relationship between objective metrics of sensory processing and clinical symptoms, however, are surprisingly sparse. Here we examined the relationship between neurophysiological assays of sensory processing and (1) autism severity and (2) sensory sensitivities, in individuals with ASD aged 6-17. Multiple linear regression indicated significant associations between neural markers of auditory processing and multisensory integration, and autism severity. No such relationships were apparent for clinical measures of visual/auditory sensitivities. These data support that aberrant early sensory processing contributes to autism symptoms, and reveal the potential of electrophysiology to objectively subtype autism.

  16. Effects of multisensory yoga on behavior in a male child with Apert and Asperger syndrome.

    PubMed

    Scroggins, Michaela L; Litchke, Lyn G; Liu, Ting

    2016-01-01

    This case focused on a 7-year-old boy with Apert and Asperger's syndrome who attended 8, 45 min multisensory yoga sessions, twice a week, during 4-week camp. Results from the pre- and post-tests on Treatment and Research Institute for Autism Social Skills Assessment showed improvements in the total score changes from 19 to 7 for disruptive behaviors. Sparks Target Behavior Checklist scores changed from eight to one showing progression in ability to stay on task. Yoga Pose Rating Scale displayed the transformation in total scores from 80 = emerging to 115 = consistency in pose performance. The field notes revealed the positive development in expressive emotions, social engagement, and decline in looking around. Outside class parent and school behavioral specialist reported the improved ability to self-regulate stress using lion's breath and super brain. These findings indicate an improvement in behaviors that influenced the physical performance, emotional expression, and social interaction after yoga training for this child.

  17. Multi-Sensory Aerosol Data and the NRL NAAPS model for Regulatory Exceptional Event Analysis

    NASA Astrophysics Data System (ADS)

    Husar, R. B.; Hoijarvi, K.; Westphal, D. L.; Haynes, J.; Omar, A. H.; Frank, N. H.

    2013-12-01

    Beyond scientific exploration and analysis, multi-sensory observations along with models are finding increasing applications for operational air quality management. EPA's Exceptional Event (EE) Rule allows the exclusion of data strongly influenced by impacts from "exceptional events," such as smoke from wildfires or dust from abnormally high winds. The EE Rule encourages the use of satellite observations and other non-standard data along with models as evidence for formal documentation of EE samples for exclusion. Thus, the implementation of the EE Rule is uniquely suited for the direct application of integrated multi-sensory observations and indirectly through the assimilation into an aerosol simulation model. Here we report the results of a project: NASA and NAAPS Products for Air Quality Decision Making. The project uses of observations from multiple satellite sensors, surface-based aerosol measurements and the NRL Aerosol Analysis and Prediction System (NAAPS) model that assimilates key satellite observations. The satellite sensor data for detecting and documenting smoke and dust events include: MODIS AOD and Images; OMI Aerosol Index, Tropospheric NO2; AIRS, CO. The surface observations include the EPA regulatory PM2.5 network; the IMPROVE/STN aerosol chemical network; AIRNOW PM2.5 mass network, and surface met. data. Within this application, crucial role is assigned to the NAAPS model for estimating the surface concentration of windblown dust and biomass smoke. The operational model assimilates quality-assured daily MODIS data and 2DVAR to adjust the model concentrations and CALIOP-based climatology to adjust the vertical profiles at 6-hour intervals. The assimilation of satellite data from multiple satellites significantly contributes to the usefulness of NAAPS for EE analysis. The NAAPS smoke and dust simulations were evaluated using the IMPROVE/STN chemical data. The multi-sensory observations along with the model simulations are integrated into a web

  18. Neurophysiological indices of atypical auditory processing and multisensory integration are associated with symptom severity in autism

    PubMed Central

    Brandwein, A.B.; Foxe, J.J.; Butler, J.S.; Frey, H.P.; Bates, J.C.; Shulman, L.; Molholm, S.

    2014-01-01

    Atypical processing and integration of sensory inputs are hypothesized to play a role in unusual sensory reactions and social-cognitive deficits in autism spectrum disorder (ASD). Reports on the relationship between objective metrics of sensory processing and clinical symptoms, however, are surprisingly sparse. Here we examined the relationship between neurophysiological assays of sensory processing and 1) autism severity and 2) sensory sensitivities, in individuals with ASD aged 6–17. Multiple linear regression indicated significant associations between neural markers of auditory processing and multisensory integration, and autism severity. No such relationships were apparent for clinical measures of visual/auditory sensitivities. These data support that aberrant early sensory processing contributes to autism symptoms, and reveal the potential of electrophysiology to objectively subtype autism. PMID:25245785

  19. The effect of manipulability and religion on the multisensory integration of objects in peripersonal space.

    PubMed

    van Elk, Michiel

    2014-01-01

    In this study participants were required to respond to vibrotactile stimuli applied to the hand while ignoring visual distractors superimposed on pictures representing Christian, Hindu, or profane objects that were categorized as manipulable or non-manipulable. Overall, participants responded slower when the visual distractor appeared at an incongruent location with respect to the vibrotactile stimulus, which is known as the crossmodal congruency effect (i.e., CCE). The CCE was modulated by the type of object involved (i.e., Christian, Hindu, or Profane), the object manipulability (i.e., manipulable vs. non-manipulable) and the religious background of the participant (i.e., Christian, Hindu, or non-religious). The finding that both object manipulability, the religious significance of the object, and the religious background of the participant have a combined effect on multisensory integration suggests important interactions between low-level body-object integration and the symbolic extension of the self.

  20. Multisensory systems integration for high-performance motor control in flies

    PubMed Central

    Frye, Mark A.

    2010-01-01

    Summary Engineered tracking systems ‘fuse’ data from disparate sensor platforms, such as radar and video, to synthesize information that is more reliable than any single input. The mammalian brain registers visual and auditory inputs to directionally localize an interesting environmental feature. For a fly, sensory perception is challenged by the extreme performance demands of high speed flight. Yet even a fruit fly can robustly track a fragmented odor plume through varying visual environments, outperforming any human engineered robot. Flies integrate disparate modalities, such as vision and olfaction, which are neither related by spatiotemporal spectra nor processed by registered neural tissue maps. Thus, the fly is motivating new conceptual frameworks for how low-level multisensory circuits and functional algorithms produce high-performance motor control. PMID:20202821

  1. Multisensory stimulation with other-race faces and the reduction of racial prejudice.

    PubMed

    Estudillo, Alejandro J; Bindemann, Markus

    2016-05-01

    This study investigated whether multisensory stimulation with other-race faces can reduce racial prejudice. In three experiments, the faces of Caucasian observers were stroked with a cotton bud while they watched a black face being stroked in synchrony on a computer screen. This was compared with a neutral condition, in which no tactile stimulation was administered (Experiment 1 and 2), and with a condition in which observers' faces were stroked in asynchrony with the onscreen face (Experiment 3). In all experiments, observers experienced an enfacement illusion after synchronous stimulation, whereby they reported to embody the other-race face. However, this effect did not produce concurrent changes in implicit or explicit racial prejudice. This outcome contrasts with other procedures for the reduction of self-other differences that decrease racial prejudice, such as behavioural mimicry and intergroup contact. We speculate that enfacement is less effective for such prejudice reduction because it does not encourage perspective-taking.

  2. Multisensory control of multimodal behavior: do the legs know what the tongue is doing?

    PubMed

    Cushman, Jesse D; Aharoni, Daniel B; Willers, Bernard; Ravassard, Pascal; Kees, Ashley; Vuong, Cliff; Popeney, Briana; Arisaka, Katsushi; Mehta, Mayank R

    2013-01-01

    Understanding of adaptive behavior requires the precisely controlled presentation of multisensory stimuli combined with simultaneous measurement of multiple behavioral modalities. Hence, we developed a virtual reality apparatus that allows for simultaneous measurement of reward checking, a commonly used measure in associative learning paradigms, and navigational behavior, along with precisely controlled presentation of visual, auditory and reward stimuli. Rats performed a virtual spatial navigation task analogous to the Morris maze where only distal visual or auditory cues provided spatial information. Spatial navigation and reward checking maps showed experience-dependent learning and were in register for distal visual cues. However, they showed a dissociation, whereby distal auditory cues failed to support spatial navigation but did support spatially localized reward checking. These findings indicate that rats can navigate in virtual space with only distal visual cues, without significant vestibular or other sensory inputs. Furthermore, they reveal the simultaneous dissociation between two reward-driven behaviors.

  3. Effects of multisensory yoga on behavior in a male child with Apert and Asperger syndrome

    PubMed Central

    Scroggins, Michaela L; Litchke, Lyn G; Liu, Ting

    2016-01-01

    This case focused on a 7-year-old boy with Apert and Asperger's syndrome who attended 8, 45 min multisensory yoga sessions, twice a week, during 4-week camp. Results from the pre- and post-tests on Treatment and Research Institute for Autism Social Skills Assessment showed improvements in the total score changes from 19 to 7 for disruptive behaviors. Sparks Target Behavior Checklist scores changed from eight to one showing progression in ability to stay on task. Yoga Pose Rating Scale displayed the transformation in total scores from 80 = emerging to 115 = consistency in pose performance. The field notes revealed the positive development in expressive emotions, social engagement, and decline in looking around. Outside class parent and school behavioral specialist reported the improved ability to self-regulate stress using lion's breath and super brain. These findings indicate an improvement in behaviors that influenced the physical performance, emotional expression, and social interaction after yoga training for this child. PMID:26865777

  4. Multisensory integration of drumming actions: musical expertise affects perceived audiovisual asynchrony.

    PubMed

    Petrini, Karin; Dahl, Sofia; Rocchesso, Davide; Waadeland, Carl Haakon; Avanzini, Federico; Puce, Aina; Pollick, Frank E

    2009-09-01

    We investigated the effect of musical expertise on sensitivity to asynchrony for drumming point-light displays, which varied in their physical characteristics (Experiment 1) or in their degree of audiovisual congruency (Experiment 2). In Experiment 1, 21 repetitions of three tempos x three accents x nine audiovisual delays were presented to four jazz drummers and four novices. In Experiment 2, ten repetitions of two audiovisual incongruency conditions x nine audiovisual delays were presented to 13 drummers and 13 novices. Participants gave forced-choice judgments of audiovisual synchrony. The results of Experiment 1 show an enhancement in experts' ability to detect asynchrony, especially for slower drumming tempos. In Experiment 2 an increase in sensitivity to asynchrony was found for incongruent stimuli; this increase, however, is attributable only to the novice group. Altogether the results indicated that through musical practice we learn to ignore variations in stimulus characteristics that otherwise would affect our multisensory integration processes.

  5. Learning across senses: cross-modal effects in multisensory statistical learning.

    PubMed

    Mitchel, Aaron D; Weiss, Daniel J

    2011-09-01

    It is currently unknown whether statistical learning is supported by modality-general or modality-specific mechanisms. One issue within this debate concerns the independence of learning in one modality from learning in other modalities. In the present study, the authors examined the extent to which statistical learning across modalities is independent by simultaneously presenting learners with auditory and visual streams. After establishing baseline rates of learning for each stream independently, they systematically varied the amount of audiovisual correspondence across 3 experiments. They found that learners were able to segment both streams successfully only when the boundaries of the audio and visual triplets were in alignment. This pattern of results suggests that learners are able to extract multiple statistical regularities across modalities provided that there is some degree of cross-modal coherence. They discuss the implications of their results in light of recent claims that multisensory statistical learning is guided by modality-independent mechanisms.

  6. Interactions between the spatial and temporal stimulus factors that influence multisensory integration in human performance

    PubMed Central

    Stevenson, Ryan A.; Fister, Juliane Krueger; Barnett, Zachary P.; Nidiffer, Aaron R.; Wallace, Mark T.

    2012-01-01

    In natural environments, human sensory systems work in a coordinated and integrated manner to perceive and respond to external events. Previous research has shown that the spatial and temporal relationships of sensory signals are paramount in determining how information is integrated across sensory modalities, but in ecologically plausible settings, these factors are not independent. In the current study we provide a novel exploration of the impact on behavioral performance for systematic manipulations of the spatial location and temporal synchrony of a visual-auditory stimulus pair. Simple auditory and visual stimuli were presented across a range of spatial locations and stimulus onset asynchronies (SOAs), and participants performed both a spatial localization and simultaneity judgment task. Response times in localizing paired visual-auditory stimuli were slower in the periphery and at larger SOAs, but most importantly, an interaction was found between the two factors, in which the effect of SOA was greater in peripheral as opposed to central locations. Simultaneity judgments also revealed a novel interaction between space and time: individuals were more likely to judge stimuli as synchronous occurring in the periphery at large SOAs. The results of this study provide novel insights into (a) how the speed of spatial localization of an audiovisual stimulus is affected by location and temporal coincidence and the interaction between these two factors, and (b) how the location of a multisensory stimulus impacts judgments concerning the temporal relationship of the paired stimuli. These findings provide strong evidence for a complex interdependency between spatial location and temporal structure in determining the ultimate behavioral and perceptual outcome associated with a paired multisensory (i.e., visual-auditory) stimulus. PMID:22447249

  7. The Multisensory Attentional Consequences of Tool Use: A Functional Magnetic Resonance Imaging Study

    PubMed Central

    Holmes, Nicholas P.; Spence, Charles; Hansen, Peter C.; Mackay, Clare E.; Calvert, Gemma A.

    2008-01-01

    Background Tool use in humans requires that multisensory information is integrated across different locations, from objects seen to be distant from the hand, but felt indirectly at the hand via the tool. We tested the hypothesis that using a simple tool to perceive vibrotactile stimuli results in the enhanced processing of visual stimuli presented at the distal, functional part of the tool. Such a finding would be consistent with a shift of spatial attention to the location where the tool is used. Methodology/Principal Findings We tested this hypothesis by scanning healthy human participants' brains using functional magnetic resonance imaging, while they used a simple tool to discriminate between target vibrations, accompanied by congruent or incongruent visual distractors, on the same or opposite side to the tool. The attentional hypothesis was supported: BOLD response in occipital cortex, particularly in the right hemisphere lingual gyrus, varied significantly as a function of tool position, increasing contralaterally, and decreasing ipsilaterally to the tool. Furthermore, these modulations occurred despite the fact that participants were repeatedly instructed to ignore the visual stimuli, to respond only to the vibrotactile stimuli, and to maintain visual fixation centrally. In addition, the magnitude of multisensory (visual-vibrotactile) interactions in participants' behavioural responses significantly predicted the BOLD response in occipital cortical areas that were also modulated as a function of both visual stimulus position and tool position. Conclusions/Significance These results show that using a simple tool to locate and to perceive vibrotactile stimuli is accompanied by a shift of spatial attention to the location where the functional part of the tool is used, resulting in enhanced processing of visual stimuli at that location, and decreased processing at other locations. This was most clearly observed in the right hemisphere lingual gyrus. Such

  8. Designing Driver Assistance Systems with Crossmodal Signals: Multisensory Integration Rules for Saccadic Reaction Times Apply

    PubMed Central

    Steenken, Rike; Weber, Lars; Colonius, Hans; Diederich, Adele

    2014-01-01

    Modern driver assistance systems make increasing use of auditory and tactile signals in order to reduce the driver's visual information load. This entails potential crossmodal interaction effects that need to be taken into account in designing an optimal system. Here we show that saccadic reaction times to visual targets (cockpit or outside mirror), presented in a driving simulator environment and accompanied by auditory or tactile accessories, follow some well-known spatiotemporal rules of multisensory integration, usually found under confined laboratory conditions. Auditory nontargets speed up reaction time by about 80 ms. The effect tends to be maximal when the nontarget is presented 50 ms before the target and when target and nontarget are spatially coincident. The effect of a tactile nontarget (vibrating steering wheel) was less pronounced and not spatially specific. It is shown that the average reaction times are well-described by the stochastic “time window of integration” model for multisensory integration developed by the authors. This two-stage model postulates that crossmodal interaction occurs only if the peripheral processes from the different sensory modalities terminate within a fixed temporal interval, and that the amount of crossmodal interaction manifests itself in an increase or decrease of second stage processing time. A qualitative test is consistent with the model prediction that the probability of interaction, but not the amount of crossmodal interaction, depends on target–nontarget onset asynchrony. A quantitative model fit yields estimates of individual participants' parameters, including the size of the time window. Some consequences for the design of driver assistance systems are discussed. PMID:24800823

  9. Characterizing the roles of alpha and theta oscillations in multisensory attention.

    PubMed

    Keller, Arielle S; Payne, Lisa; Sekuler, Robert

    2017-03-01

    Cortical alpha oscillations (8-13Hz) appear to play a role in suppressing distractions when just one sensory modality is being attended, but do they also contribute when attention is distributed over multiple sensory modalities? For an answer, we examined cortical oscillations in human subjects who were dividing attention between auditory and visual sequences. In Experiment 1, subjects performed an oddball task with auditory, visual, or simultaneous audiovisual sequences in separate blocks, while the electroencephalogram was recorded using high-density scalp electrodes. Alpha oscillations were present continuously over posterior regions while subjects were attending to auditory sequences. This supports the idea that the brain suppresses processing of visual input in order to advantage auditory processing. During a divided-attention audiovisual condition, an oddball (a rare, unusual stimulus) occurred in either the auditory or the visual domain, requiring that attention be divided between the two modalities. Fronto-central theta band (4-7Hz) activity was strongest in this audiovisual condition, when subjects monitored auditory and visual sequences simultaneously. Theta oscillations have been associated with both attention and with short-term memory. Experiment 2 sought to distinguish these possible roles of fronto-central theta activity during multisensory divided attention. Using a modified version of the oddball task from Experiment 1, Experiment 2 showed that differences in theta power among conditions were independent of short-term memory load. Ruling out theta's association with short-term memory, we conclude that fronto-central theta activity is likely a marker of multisensory divided attention.

  10. Design and Test of a Biosensor-Based Multisensorial System: A Proof of Concept Study

    PubMed Central

    Santonico, Marco; Pennazza, Giorgio; Grasso, Simone; D'Amico, Arnaldo; Bizzarri, Mariano

    2013-01-01

    Sensors are often organized in multidimensional systems or networks for particular applications. This is facilitated by the large improvements in the miniaturization process, power consumption reduction and data analysis techniques nowadays possible. Such sensors are frequently organized in multidimensional arrays oriented to the realization of artificial sensorial systems mimicking the mechanisms of human senses. Instruments that make use of these sensors are frequently employed in the fields of medicine and food science. Among them, the so-called electronic nose and tongue are becoming more and more popular. In this paper an innovative multisensorial system based on sensing materials of biological origin is illustrated. Anthocyanins are exploited here as chemical interactive materials for both quartz microbalance (QMB) transducers used as gas sensors and for electrodes used as liquid electrochemical sensors. The optical properties of anthocyanins are well established and widely used, but they have never been exploited as sensing materials for both gas and liquid sensors in non-optical applications. By using the same set of selected anthocyanins an integrated system has been realized, which includes a gas sensor array based on QMB and a sensor array for liquids made up of suitable Ion Sensitive Electrodes (ISEs). The arrays are also monitored from an optical point of view. This embedded system, is intended to mimic the working principles of the nose, tongue and eyes. We call this setup BIONOTE (for BIOsensor-based multisensorial system for mimicking NOse, Tongue and Eyes). The complete design, fabrication and calibration processes of the BIONOTE system are described herein, and a number of preliminary results are discussed. These results are relative to: (a) the characterization of the optical properties of the tested materials; (b) the performance of the whole system as gas sensor array with respect to ethanol, hexane and isopropyl alcohol detection

  11. Designing driver assistance systems with crossmodal signals: multisensory integration rules for saccadic reaction times apply.

    PubMed

    Steenken, Rike; Weber, Lars; Colonius, Hans; Diederich, Adele

    2014-01-01

    Modern driver assistance systems make increasing use of auditory and tactile signals in order to reduce the driver's visual information load. This entails potential crossmodal interaction effects that need to be taken into account in designing an optimal system. Here we show that saccadic reaction times to visual targets (cockpit or outside mirror), presented in a driving simulator environment and accompanied by auditory or tactile accessories, follow some well-known spatiotemporal rules of multisensory integration, usually found under confined laboratory conditions. Auditory nontargets speed up reaction time by about 80 ms. The effect tends to be maximal when the nontarget is presented 50 ms before the target and when target and nontarget are spatially coincident. The effect of a tactile nontarget (vibrating steering wheel) was less pronounced and not spatially specific. It is shown that the average reaction times are well-described by the stochastic "time window of integration" model for multisensory integration developed by the authors. This two-stage model postulates that crossmodal interaction occurs only if the peripheral processes from the different sensory modalities terminate within a fixed temporal interval, and that the amount of crossmodal interaction manifests itself in an increase or decrease of second stage processing time. A qualitative test is consistent with the model prediction that the probability of interaction, but not the amount of crossmodal interaction, depends on target-nontarget onset asynchrony. A quantitative model fit yields estimates of individual participants' parameters, including the size of the time window. Some consequences for the design of driver assistance systems are discussed.

  12. DNA damage-induced translocation of S100A11 into the nucleus regulates cell proliferation

    PubMed Central

    2010-01-01

    Background Proteins are able to react in response to distinct stress stimuli by alteration of their subcellular distribution. The stress-responsive protein S100A11 belongs to the family of multifunctional S100 proteins which have been implicated in several key biological processes. Previously, we have shown that S100A11 is directly involved in DNA repair processes at damaged chromatin in the nucleus. To gain further insight into the underlying mechanism subcellular trafficking of S100A11 in response to DNA damage was analyzed. Results We show that DNA damage induces a nucleolin-mediated translocation of S100A11 from the cytoplasm into the nucleus. This translocation is impeded by inhibition of the phosphorylation activity of PKCα. Translocation of S100A11 into the nucleus correlates with an increased cellular p21 protein level. Depletion of nucleolin by siRNA severely impairs translocation of S100A11 into the nucleus resulting in a decreased p21 protein level. Additionally, cells lacking nucleolin showed a reduced colony forming capacity. Conclusions These observations suggest that regulation of the subcellular distribution of S100A11 plays an important role in the DNA damage response and p21-mediated cell cycle control. PMID:21167017

  13. Spatio-temporal measures of electrophysiological correlates for behavioral multisensory enhancement during visual, auditory and somatosensory stimulation: A behavioral and ERP study.

    PubMed

    Wang, Wuyi; Hu, Li; Cui, Hongyan; Xie, Xiaobo; Hu, Yong

    2013-12-01

    Multisensory enhancement, as a facilitation phenomenon, is responsible for superior behavioral performance when an individual is responding to cross-modal versus modality-specific stimuli. However, the event-related potential (ERP) counterparts of behavioral multisensory enhancement are not well known. We recorded ERPs and behavioral data from 14 healthy volunteers with three types of target stimuli (modality-specific, bimodal, and trimodal) to examine the spatio-temporal electrophysiological characteristics of multisensory enhancement by comparing behavioral data with ERPs. We found a strong correlation between P3 latency and behavioral performance in terms of reaction time (RT) (R = 0.98, P <0.001), suggesting that P3 latency constitutes a temporal measure of behavioral multisensory enhancement. In addition, a fast RT and short P3 latency were found when comparing the modality-specific visual target with the modality-specific auditory and somatosensory targets. Our results indicate that behavioral multisensory enhancement can be identified by the latency and source distribution of the P3 component. These findings may advance our understanding of the neuronal mechanisms of multisensory enhancement.

  14. Hummingbird Comet Nucleus Analysis Mission

    NASA Technical Reports Server (NTRS)

    Kojiro, Daniel; Carle, Glenn C.; Lasher, Larry E.

    2000-01-01

    Hummingbird is a highly focused scientific mission, proposed to NASA s Discovery Program, designed to address the highest priority questions in cometary science-that of the chemical composition of the cometary nucleus. After rendezvous with the comet, Hummingbird would first methodically image and map the comet, then collect and analyze dust, ice and gases from the cometary atmosphere to enrich characterization of the comet and support landing site selection. Then, like its namesake, Hummingbird would carefully descend to a pre-selected surface site obtaining a high-resolution image, gather a surface material sample, acquire surface temperature and then immediately return to orbit for detailed chemical and elemental analyses followed by a high resolution post-sampling image of the site. Hummingbird s analytical laboratory contains instrumentation for a comprehensive molecular and elemental analysis of the cometary nucleus as well as an innovative surface sample acquisition device.

  15. Checkerboard Theory of the Nucleus.

    NASA Astrophysics Data System (ADS)

    Lach, Theodore

    2006-04-01

    The Checker Board Model (CBM) is a 2D model of the nucleus that proposes that the synchronization of the 2 outer rotating quarks in the nucleons accounts for magnetic moment of the nucleons and that the magnetic flux from the nucleons couples (weaves) into the 2D checker board array structures and this magnetic coupling in addition to electrostatic forces of the rotating and stationary quarks accounts for the apparent strong nuclear force. The symmetry of the He nucleus helps explain why this 2D structure is so stable. This model explain the mass of the proton and neutron, along with their magnetic moments and their absolute and relative sizes in terms of the above structure and predict the masses of two newly proposed quarks ^(1): the ``up'' and the ``dn'' quarks. Since the masses of the ``up'' and ``dn'' quark determined by the CBM (237.31 MeV and 42.392 MeV respectively) did not fit within the standard model as candidates for u and d, a new model (New Physics) had to be invented. This new particle physics model predicts that nature has 5 generations not 3. (1). T.M. Lach, Checkerboard Structure of the Nucleus, Infinite Energy, Vol. 5, issue 30, (2000). (2). T.M. Lach, Masses of the Sub-Nuclear Particles, nucl-th/0008026, @http://xxx.lanl.gov/

  16. Long-distance feedback projections to area V1: implications for multisensory integration, spatial awareness, and visual consciousness.

    PubMed

    Clavagnier, Simon; Falchier, Arnaud; Kennedy, Henry

    2004-06-01

    It is generally agreed that information flow through the cortex is constrained by a hierarchical architecture. Recent experimental evidence suggests that projections descending the hierarchy and targeting the primary visual cortex (area V1) may play an essential role in perceptual processes. We have, therefore, reexamined feedback projections to area V1, using retrograde tracer injections in this area In addition to well-known areas, quantification of labeling in higher cortical areas reveals a number of hitherto unknown long-distance feedback connections originating from auditory (A1), multisensory (STP) cortices, but also from a perirhinal area (36). These feedback projections from advanced cortical stations, a global feature shared by areas that belong to the ventral visual stream, could play an important role in early multisensory integration and spatial awareness and could provide the physical substrate for the involvement of area V1 in visual consciousness.

  17. Zapping the gap: Reducing the multisensory temporal binding window by means of transcranial direct current stimulation (tDCS).

    PubMed

    Zmigrod, Sharon; Zmigrod, Leor

    2015-09-01

    Synchrony among the senses lies at the heart of our possession of a unified conscious perception of the world. However, due to discrepancies in physical and neural information processing from different senses, the brain accommodates a limited range of temporal asynchronies between sensory inputs, i.e. the multisensory temporal binding window (TBW). Using non-invasive brain stimulation, we sought to modulate the audio-visual TBW and to identify cortical areas implicated in the conscious perception of multisensory synchrony. Participants performed a simultaneity judgment task while experiencing anodal (Experiment 1) or cathodal (Experiment 2) transcranial direct current stimulation (tDCS) over parietal and frontal regions. The results demonstrate that stimulating the right posterior parietal cortex significantly reduces the audio-visual TBW by approximately 30%, thereby causally linking this region to the plasticity of the TBW. This highlights a potential interventional technique for populations with a wider TBW, such as in autism and dyslexia.

  18. Effects of Multisensory Stimulation on a Sample of Institutionalized Elderly People With Dementia Diagnosis: A Controlled Longitudinal Trial.

    PubMed

    Maseda, Ana; Sánchez, Alba; Marante, M Pilar; González-Abraldes, Isabel; Buján, Ana; Millán-Calenti, José Carlos

    2014-08-01

    Long-term effects of multisensory stimulation were assessed using a "Snoezelen" room on older residents with dementia. Thirty patients were randomly assigned to 3 groups: multisensory stimulation environment (MSSE) group, individualized activities (activity) group, and control group. The MSSE and activity groups participated in two 30-minute weekly individualized intervention sessions over 16 weeks. Pre-, mid-, posttrial, and 8-week follow-up behavior, mood, cognitive, and functional impairment in basic activities of daily living were registered. Items included in the physically nonaggressive behavior factor improved significantly in post- versus pretrial in the MSSE group compared to the activity group, with no significant differences between MSSE and control groups. The MSSE and activity groups demonstrated behavior improvements and higher scores on the Cohen-Mansfield agitation inventory, verbal agitated behavior factor, and Neuropsychiatric Inventory-Nursing Home, with no significant differences between groups. The MSSE could have long-term positive effects on such neuropsychiatric symptoms in older people with dementia.

  19. Classifiers for centrality determination in proton-nucleus and nucleus-nucleus collisions

    NASA Astrophysics Data System (ADS)

    Altsybeev, Igor; Kovalenko, Vladimir

    2017-03-01

    Centrality, as a geometrical property of the collision, is crucial for the physical interpretation of nucleus-nucleus and proton-nucleus experimental data. However, it cannot be directly accessed in event-by-event data analysis. Common methods for centrality estimation in A-A and p-A collisions usually rely on a single detector (either on the signal in zero-degree calorimeters or on the multiplicity in some semi-central rapidity range). In the present work, we made an attempt to develop an approach for centrality determination that is based on machine-learning techniques and utilizes information from several detector subsystems simultaneously. Different event classifiers are suggested and evaluated for their selectivity power in terms of the number of nucleons-participants and the impact parameter of the collision. Finer centrality resolution may allow to reduce impact from so-called volume fluctuations on physical observables being studied in heavy-ion experiments like ALICE at the LHC and fixed target experiment NA61/SHINE on SPS.

  20. Photoproduction of lepton pairs in proton-nucleus and nucleus-nucleus collisions at RHIC and LHC energies

    SciTech Connect

    Moreira, B. D.; Goncalves, V. P.; De Santana Amaral, J. T.

    2013-03-25

    In this contribution we study coherent interactions as a probe of the nonlinear effects in the Quantum Electrodynamics (QED). In particular, we study the multiphoton effects in the production of leptons pairs for proton-nucleus and nucleus-nucleus collisions for heavy nuclei. In the proton-nucleus we assume the ultrarelativistic proton as a source of photons and estimate the photoproduction of lepton pairs on nuclei at RHIC and LHC energies considering the multiphoton effects associated to multiple rescattering of the projectile photon on the proton of the nucleus. In nucleus - nucleus colllisions we consider the two nuclei as a source of photons. As each scattering contributes with a factor {alpha}Z to the cross section, this contribution must be taken into account for heavy nuclei. We consider the Coulomb corrections to calculate themultiple scatterings and estimate the total cross section for muon and tau pair production in proton-nucleus and nucleus-nucleus collisions at RHIC and LHC energies.

  1. Multisensory Competition Is Modulated by Sensory Pathway Interactions with Fronto-Sensorimotor and Default-Mode Network Regions.

    PubMed

    Huang, Sai; Li, You; Zhang, Wei; Zhang, Bao; Liu, Xingzhou; Mo, Lei; Chen, Qi

    2015-06-17

    Multisensory information competes for preferential access to consciousness. It remains unknown what neural processes cause one particular modality to win multisensory competition and eventually dominate behavior. Thus, in a paradigm in which human participants sought to make simultaneous auditory and visual detection responses, we sought to identify prestimulus and poststimulus neural signals that were associated with auditory and visual dominance on each trial. Behaviorally, visual detection responses preceded auditory responses more frequently than vice versa. Even when visual responses were preceded by auditory responses, they recovered more quickly from previous responses, indicating the dominance of vision over audition. Neurally, visual precedence was associated with increased prestimulus activity in the prefrontal cortex and reduced prestimulus activity in the default-mode network, and increased poststimulus connectivity between the prefrontal cortex and the visual system. Moreover, the dorsal visual stream showed not only increased activity in post-perceptual phases but also enhanced connectivity with the sensorimotor cortex, indicating the functional role of the dorsal visual stream in prioritizing the flow of visual information into the motor system. In contrast, auditory precedence was associated with increased prestimulus activity in the auditory cortex and increased poststimulus neural coupling between the auditory and the sensorimotor cortex. Finally, whenever one modality lost multisensory competition, the corresponding sensory cortex showed enhanced connectivity with the default-mode network. Overall, the outcome of audiovisual competition depended on dynamic interactions between sensory systems and both the fronto-sensorimotor and the default-mode network. Together, these results revealed both the neural causes and the neural consequences of visual and auditory dominance during multisensory competition.

  2. Occipital transcranial magnetic stimulation has opposing effects on visual and auditory stimulus detection: implications for multisensory interactions.

    PubMed

    Romei, Vincenzo; Murray, Micah M; Merabet, Lotfi B; Thut, Gregor

    2007-10-24

    Multisensory interactions occur early in time and in low-level cortical areas, including primary cortices. To test current models of early auditory-visual (AV) convergence in unisensory visual brain areas, we studied the effect of transcranial magnetic stimulation (TMS) of visual cortex on behavioral responses to unisensory (auditory or visual) or multisensory (simultaneous auditory-visual) stimulus presentation. Single-pulse TMS was applied over the occipital pole at short delays (30-150 ms) after external stimulus onset. Relative to TMS over a control site, reactions times (RTs) to unisensory visual stimuli were prolonged by TMS at 60-75 ms poststimulus onset (visual suppression effect), confirming stimulation of functional visual cortex. Conversely, RTs to unisensory auditory stimuli were significantly shortened when visual cortex was stimulated by TMS at the same delays (beneficial interaction effect of auditory stimulation and occipital TMS). No TMS-effect on RTs was observed for AV stimulation. The beneficial interaction effect of combined unisensory auditory and TMS-induced visual cortex stimulation matched and was correlated with the RT-facilitation after external multisensory AV stimulation without TMS, suggestive of multisensory interactions between the stimulus-evoked auditory and TMS-induced visual cortex activities. A follow-up experiment showed that auditory input enhances excitability within visual cortex itself (using phosphene-induction via TMS as a measure) over a similarly early time-window (75-120 ms). The collective data support a mechanism of early auditory-visual interactions that is mediated by auditory-driven sensitivity changes in visual neurons that coincide in time with the initial volleys of visual input.

  3. Multifunctional integration: from biological to bio-inspired materials.

    PubMed

    Liu, Kesong; Jiang, Lei

    2011-09-27

    Nature is a school for human beings. Learning from nature has long been a source of bioinspiration for scientists and engineers. Multiscale structures are characteristic for biological materials, exhibiting inherent multifunctional integration. Optimized biological solutions provide inspiration for scientists and engineers to design and to fabricate multiscale structured materials for multifunctional integration.

  4. Multifunctional Flexible Composites Based on Continuous Carbon Nanotube Fiber

    DTIC Science & Technology

    2014-07-28

    applications in various fields . In this program, we systematically studied the tensile strength, compressive strength, microstructure, torsional ...of multifunctional applications in various fields . With the support of the Project “Multifunctional Flexible Composites Based on Continuous Carbon...techniques, including the tensile strength, compressive strength, microstructure evolution, torsional behavior, electromechanical response, failure

  5. Multifunctional Ultra-Light Mg-Li Alloy Nanocomposites

    DTIC Science & Technology

    2012-08-20

    Nanoccomposite Materials for Energy Storage and Multifunctional Applications at TMS, Orlando, FL (2012) (invited) 3. G. Yushin, Nanocomposite Materials for...Lithium and Beyond (invited) 4. G. Yushin, Nanocomposite Carbon-Containing Materials for Energy Storage and Multifunctional Applications , at the... Nanocomposite Materials for Energy Storage Applications , at the 2nd UNIST International Conference, which took place in Ulsan, Korea (2010) (invited

  6. Multifunctional UV (MUV) Coatings and Ce-based Materials

    DTIC Science & Technology

    2008-02-01

    Coat Metallic Substrate Non-Chromate Conversion Coating Multifunctional UV (MUV)- Curable Coating Current 3...Layer, Cr(VI) Based Coating System 2 Layer, UV Curable Coating System With No Cr(VI) and No VOCs Technical Objective Surface Finishing Workshop Feb 08... UV Curable Coatings and Inhibitors Non-Chromate Pretreatments Multifunctional UV (MUV) Coating Conversion Coating Characterization,

  7. Nanodumbbells as multi-functional diagnosis probes

    NASA Astrophysics Data System (ADS)

    Wang, Hui; Rauf, Sakandar; Padmanabhan, Harish; Dimitrov, Krassen

    2013-05-01

    In this study, we present a method to generate multi-functional nanometre dumbbell structure, which comprises a cobalt magnetic and a gold nanoparticle bridged by target biomarker. Both cobalt magnetic and gold nanoparticles were successfully modified with two different monoclonal antibodies, which will specifically bind to target antigen. ELISA results confirmed that the activities of those antibodies were not lost due to the conjugation to nanoparticles. The formation of dumbbell structure with the presence of target biomarker molecule was demonstrated via scanning electron microscope. The success of this study allows us to apply this featured dumbbell structure into a nanoelectrode device for digital detection of diagnostic biomarker in the next step.

  8. Multifunctional Nanotherapeutic System for Advanced Prostate Cancer

    DTIC Science & Technology

    2012-10-01

    delivery of eIF4E siRNA and DTX using dendrimer as a nanocarrier. To this end the objective of this study is to prepare, characterize and test the...multifunctional delivery system by conjugating DTX to dendrimer and complexing eIF4E siRNA to the resulting conjugate. The DTX- dendrimer conjugate...formed complex with siRNA at 20:1 ratio. The dendrimer - siRNA complex was taken up by the prostate cancer cells while the free siRNA was not taken up by

  9. Ultrastrong, Stiff and Multifunctional Carbon Nanotube Composites

    SciTech Connect

    Wang, Xin; Yong, Zhenzhong; Li, Qingwen; Bradford, Philip D.; Liu, Wei; Tucker, Dennis S.; Cai, Wei; Wang, Hsin; Yuan, Fuh-Gwo; Zhu, Yuntian

    2012-01-01

    Carbon nanotubes (CNTs) are an order of magnitude stronger than any current engineering fiber. However, for the past two decades it has been a challenge to utilize their reinforcement potential in composites. Here we report CNT composites with unprecedented multifunctionalities, including record high strength (3.8 GPa), Young s modulus (293 GPa), electrical conductivity (1230 S cm-1) and thermal conductivity (41 W m-1 K-1). These superior properties are derived from the long length, high volume fraction, good alignment and reduced waviness of the CNTs, which were produced by a novel processing approach that can be easily scaled up for industrial production.

  10. Requirements for a multifunctional code architecture

    SciTech Connect

    Tiihonen, O.; Juslin, K.

    1997-07-01

    The present paper studies a set of requirements for a multifunctional simulation software architecture in the light of experiences gained in developing and using the APROS simulation environment. The huge steps taken in the development of computer hardware and software during the last ten years are changing the status of the traditional nuclear safety analysis software. The affordable computing power on the safety analysts table by far exceeds the possibilities offered to him/her ten years ago. At the same time the features of everyday office software tend to set standards to the way the input data and calculational results are managed.

  11. Multifunctional 2D- Materials: Selenides and Halides

    NASA Technical Reports Server (NTRS)

    Singh, N. B.; Su, Ching Hua; Arnold, Brad; Choa, Fow-Sen; Bohorfous, Sara

    2016-01-01

    Material is the key component and controls the performance of the detectors, devices and sensors. The materials design, processing, growth and fabrication of bulk and nanocrystals and fabrication into devices and sensors involve multidisciplinary team of experts. This places a large burden on the cost of the novel materials development. Due to this reason there is a big thrust for the prediction of multifunctionality of materials before design and development. Up to some extent design can achieve certain properties. In multinary materials processing is also a big factor. In this presentation, examples of two classes of industrially important materials will be described.

  12. Multifunctional epitaxial systems on silicon substrates

    NASA Astrophysics Data System (ADS)

    Singamaneni, Srinivasa Rao; Prater, John Thomas; Narayan, Jagdish

    2016-09-01

    Multifunctional heterostructures can exhibit a wide range of functional properties, including colossal magneto-resistance, magnetocaloric, and multiferroic behavior, and can display interesting physical phenomena including spin and charge ordering and strong spin-orbit coupling. However, putting this functionality to work remains a challenge. To date, most of the work reported in the literature has dealt with heterostructures deposited onto closely lattice matched insulating substrates such as DyScO3, SrTiO3 (STO), or STO buffered Si(100) using concepts of lattice matching epitaxy (LME). However, strain in heterostructures grown by LME is typically not fully relaxed and the layers contain detrimental defects such as threading dislocations that can significantly degrade the physical properties of the films and adversely affect the device characteristics. In addition, most of the substrates are incompatible with existing CMOS-based technology, where Si (100) substrates dominate. This review discusses recent advances in the integration of multifunctional oxide and non-oxide materials onto silicon substrates. An alternative thin film growth approach, called "domain matching epitaxy," is presented which identifies approaches for minimizing lattice strain and unwanted defects in large misfit systems (7%-25% and higher). This approach broadly allows for the integration of multifunctional materials onto silicon substrates, such that sensing, computation, and response functions can be combined to produce next generation "smart" devices. In general, pulsed laser deposition has been used to epitaxially grow these materials, although the concepts developed here can be extended to other deposition techniques, as well. It will be shown that TiN and yttria-stabilized zirconia template layers provide promising platforms for the integration of new functionality into silicon-based computer chips. This review paper reports on a number of thin-film heterostructure systems that span a

  13. Predicting the Multisensory Consequences of One’s Own Action: BOLD Suppression in Auditory and Visual Cortices

    PubMed Central

    van Kemenade, Bianca M.; Arikan, B. Ezgi; Fiehler, Katja; Leube, Dirk T.; Harris, Laurence R.; Kircher, Tilo

    2017-01-01

    Predictive mechanisms are essential to successfully interact with the environment and to compensate for delays in the transmission of neural signals. However, whether and how we predict multisensory action outcomes remains largely unknown. Here we investigated the existence of multisensory predictive mechanisms in a context where actions have outcomes in different modalities. During fMRI data acquisition auditory, visual and auditory-visual stimuli were presented in active and passive conditions. In the active condition, a self-initiated button press elicited the stimuli with variable short delays (0-417ms) between action and outcome, and participants had to detect the presence of a delay for auditory or visual outcome (task modality). In the passive condition, stimuli appeared automatically, and participants had to detect the number of stimulus modalities (unimodal/bimodal). For action consequences compared to identical but unpredictable control stimuli we observed suppression of the blood oxygen level depended (BOLD) response in a broad network including bilateral auditory and visual cortices. This effect was independent of task modality or stimulus modality and strongest for trials where no delay was detected (undetectedmultisensory predictive mechanisms, which are probably conducted in the left cerebellum. PMID:28060861

  14. Multisensory System for Fruit Harvesting Robots. Experimental Testing in Natural Scenarios and with Different Kinds of Crops

    PubMed Central

    Fernández, Roemi; Salinas, Carlota; Montes, Héctor; Sarria, Javier

    2014-01-01

    The motivation of this research was to explore the feasibility of detecting and locating fruits from different kinds of crops in natural scenarios. To this end, a unique, modular and easily adaptable multisensory system and a set of associated pre-processing algorithms are proposed. The offered multisensory rig combines a high resolution colour camera and a multispectral system for the detection of fruits, as well as for the discrimination of the different elements of the plants, and a Time-Of-Flight (TOF) camera that provides fast acquisition of distances enabling the localisation of the targets in the coordinate space. A controlled lighting system completes the set-up, increasing its flexibility for being used in different working conditions. The pre-processing algorithms designed for the proposed multisensory system include a pixel-based classification algorithm that labels areas of interest that belong to fruits and a registration algorithm that combines the results of the aforementioned classification algorithm with the data provided by the TOF camera for the 3D reconstruction of the desired regions. Several experimental tests have been carried out in outdoors conditions in order to validate the capabilities of the proposed system. PMID:25615730

  15. Plant species richness and ecosystem multifunctionality in global drylands.

    PubMed

    Maestre, Fernando T; Quero, José L; Gotelli, Nicholas J; Escudero, Adrián; Ochoa, Victoria; Delgado-Baquerizo, Manuel; García-Gómez, Miguel; Bowker, Matthew A; Soliveres, Santiago; Escolar, Cristina; García-Palacios, Pablo; Berdugo, Miguel; Valencia, Enrique; Gozalo, Beatriz; Gallardo, Antonio; Aguilera, Lorgio; Arredondo, Tulio; Blones, Julio; Boeken, Bertrand; Bran, Donaldo; Conceição, Abel A; Cabrera, Omar; Chaieb, Mohamed; Derak, McHich; Eldridge, David J; Espinosa, Carlos I; Florentino, Adriana; Gaitán, Juan; Gatica, M Gabriel; Ghiloufi, Wahida; Gómez-González, Susana; Gutiérrez, Julio R; Hernández, Rosa M; Huang, Xuewen; Huber-Sannwald, Elisabeth; Jankju, Mohammad; Miriti, Maria; Monerris, Jorge; Mau, Rebecca L; Morici, Ernesto; Naseri, Kamal; Ospina, Abelardo; Polo, Vicente; Prina, Aníbal; Pucheta, Eduardo; Ramírez-Collantes, David A; Romão, Roberto; Tighe, Matthew; Torres-Díaz, Cristian; Val, James; Veiga, José P; Wang, Deli; Zaady, Eli

    2012-01-13

    Experiments suggest that biodiversity enhances the ability of ecosystems to maintain multiple functions, such as carbon storage, productivity, and the buildup of nutrient pools (multifunctionality). However, the relationship between biodiversity and multifunctionality has never been assessed globally in natural ecosystems. We report here on a global empirical study relating plant species richness and abiotic factors to multifunctionality in drylands, which collectively cover 41% of Earth's land surface and support over 38% of the human population. Multifunctionality was positively and significantly related to species richness. The best-fitting models accounted for over 55% of the variation in multifunctionality and always included species richness as a predictor variable. Our results suggest that the preservation of plant biodiversity is crucial to buffer negative effects of climate change and desertification in drylands.

  16. Plant species richness and ecosystem multifunctionality in global drylands

    PubMed Central

    Maestre, Fernando T.; Quero, José L.; Gotelli, Nicholas J.; Escudero, Adriá; Ochoa, Victoria; Delgado-Baquerizo, Manuel; García-Gómez, Miguel; Bowker, Matthew A.; Soliveres, Santiago; Escolar, Cristina; García-Palacios, Pablo; Berdugo, Miguel; Valencia, Enrique; Gozalo, Beatriz; Gallardo, Antonio; Aguilera, Lorgio; Arredondo, Tulio; Blones, Julio; Boeken, Bertrand; Bran, Donaldo; Conceição, Abel A.; Cabrera, Omar; Chaieb, Mohamed; Derak, Mchich; Eldridge, David J.; Espinosa, Carlos I.; Florentino, Adriana; Gaitán, Juan; Gatica, M. Gabriel; Ghiloufi, Wahida; Gómez-González, Susana; Gutiérrez, Julio R.; Hernández, Rosa M.; Huang, Xuewen; Huber-Sannwald, Elisabeth; Jankju, Mohammad; Miriti, Maria; Monerris, Jorge; Mau, Rebecca L.; Morici, Ernesto; Naseri, Kamal; Ospina, Abelardo; Polo, Vicente; Prina, Aníbal; Pucheta, Eduardo; Ramírez-Collantes, David A.; Romão, Roberto; Tighe, Matthew; Torres-Díaz, Cristian; Val, James; Veiga, José P.; Wang, Deli; Zaady, Eli

    2013-01-01

    Experiments suggest that biodiversity enhances the ability of ecosystems to maintain multiple functions, such as carbon storage, productivity, and buildup of nutrient pools (multifunctionality). However, the relationship between biodiversity and multifunctionality has never been assessed globally in natural ecosystems. We report on the first global empirical study relating plant species richness and abiotic factors to multifunctionality in drylands, which collectively cover 41% of Earth’s land surface and support over 38% of the human population. Multifunctionality was positively and significantly related to species richness. The best-fitting models accounted for over 55% of the variation in multifunctionality, and always included species richness as a predictor variable. Our results suggest that preservation of plant biodiversity is crucial to buffer negative effects of climate change and desertification in drylands. PMID:22246775

  17. Plant species richness and ecosystem multifunctionality in global drylands

    USGS Publications Warehouse

    Maestre, Fernando T.; Quero, Jose L.; Gotelli, Nicholas J.; Escudero, Adrian; Ochoa, Victoria; Delgado-Baquerizo, Manuel; Garcia-Gomez, Miguel; Bowker, Matthew A.; Soliveres, Santiago; Escolar, Cristina; Garcia-Palacios, Pablo; Berdugo, Miguel; Valencia, Enrique; Gozalo, Beatriz; Gallardo, Antonio; Aguilera, Lorgio; Arredondo, Tulio; Blones, Julio; Boeken, Bertrand; Bran, Donaldo; Conceicao, Abel A.; Cabrera, Omar; Chaieb, Mohamed; Derak, Mchich; Eldridge, David J.; Espinosa, Carlos I.; Florentino, Adriana; Gaitan, Juan; Gatica, M. Gabriel; Ghiloufi, Wahida; Gomez-Gonzalez, Susana; Gutie, Julio R.; Hernandez, Rosa M.; Huang, Xuewen; Huber-Sannwald, Elisabeth; Jankju, Mohammad; Miriti, Maria; Monerris, Jorge; Mau, Rebecca L.; Morici, Ernesto; Naseri, Kamal; Ospina, Abelardo; Polo, Vicente; Prina, Anibal; Pucheta, Eduardo; Ramirez-Collantes, David A.; Romao, Roberto; Tighe, Matthew; Torres-Diaz, Cristian; Val, James; Veiga, Jose P.; Wang, Deli; Zaady, Eli

    2012-01-01

    Experiments suggest that biodiversity enhances the ability of ecosystems to maintain multiple functions, such as carbon storage, productivity, and the buildup of nutrient pools (multifunctionality). However, the relationship between biodiversity and multifunctionality has never been assessed globally in natural ecosystems. We report here on a global empirical study relating plant species richness and abiotic factors to multifunctionality in drylands, which collectively cover 41% of Earth's land surface and support over 38% of the human population. Multifunctionality was positively and significantly related to species richness. The best-fitting models accounted for over 55% of the variation in multifunctionality and always included species richness as a predictor variable. Our results suggest that the preservation of plant biodiversity is crucial to buffer negative effects of climate change and desertification in drylands.

  18. Exceptionally bright, compact starburst nucleus

    SciTech Connect

    Margon, B.; Anderson, S.F.; Mateo, M.; Fich, M.; Massey, P.

    1988-11-01

    Observations are reported of a remarkably bright (V about 13) starburst nucleus, 0833 + 652, which has been detected at radio, infrared, optical, ultraviolet, and X-ray wavelengths. Despite an observed flux at each of these wavelengths which is comparable to that of NGC 7714, often considered the 'prototypical' example of the starburst phenomenon, 0833 + 652 appears to be a previously uncataloged object. Its ease of detectability throughout the electromagnetic spectrum should make it useful for a variety of problems in the study of compact emission-line galaxies. 30 references.

  19. Nucleus morphology of Comet Halley

    NASA Technical Reports Server (NTRS)

    Reitsema, H. J.; Delamere, W. A.; Huebner, W. F.; Keller, H. U.; Schmidt, W. K. H.; Wilhelm, K.; Schmidt, H. U.; Whipple, Fred L.

    1986-01-01

    Images obtained by the Halley multicolor camera were used to determine the projected size and shape of the nucleus. The location of the terminator and numerous surface features were determined. There is good correlation between the brightest surface features and the dust jets; however, many bright features are seen which are not associated with jets. Most of the observed features are circular and appear to be related to surface elevation. The angularity of the terminator gives an indication of the three-dimensional structure of the face which was observed.

  20. Multifunction Habitat Workstation/OLED Development

    NASA Technical Reports Server (NTRS)

    Schumacher, Shawn; Salazar, George; Schmidt, Oron

    2013-01-01

    This paper gives a general outline of both a multifunction habitat workstation and the research put into an Organic Light Emitting Diode (OLED) device. It first covers the tests that the OLED device will go through to become flight ready along with reasoning. Guidelines for building an apparatus to house the display and its components are given next, with the build of such following. The three tests the OLED goes through are presented (EMI, Thermal/Vac, Radiation) along with the data recovered. The second project of a multifunction workstation is then discussed in the same pattern. Reasoning for building such a workstation with telepresence in mind is offered. Build guidelines are presented first, with the build timeline following. Building the workstation will then be shown in great detail along with accompanying photos. Once the workstation has been discussed, the versatility of its functions are given. The paper concludes with future views and concepts that can added when the time or technology presents itself.

  1. Carbon nanotube integrated multifunctional multiscale composites

    NASA Astrophysics Data System (ADS)

    Qiu, Jingjing; Zhang, Chuck; Wang, Ben; Liang, Richard

    2007-07-01

    Carbon nanotubes (CNTs) demonstrate extraordinary properties and show great promise in enhancing out-of-plane properties of traditional polymer composites and enabling functionality, but current manufacturing challenges hinder the realization of their potential. This paper presents a method to fabricate multifunctional multiscale composites through an effective infiltration-based vacuum-assisted resin transfer moulding (VARTM) process. Multi-walled carbon nanotubes (MWNTs) were infused through and between glass-fibre tows along the through-thickness direction. Both pristine and functionalized MWNTs were used in fabricating multiscale glass-fibre-reinforced epoxy composites. It was demonstrated that the mechanical properties of multiscale composites were remarkably enhanced, especially in the functionalized MWNT multiscale composites. With only 1 wt% loading of functionalized MWNTs, tensile strength was increased by 14% and Young's modulus by 20%, in comparison with conventional fibre-reinforced composites. Moreover, the shear strength and short-beam modulus were increased by 5% and 8%, respectively, indicating the improved inter-laminar properties. The strain-stress tests also suggested noticeable enhancement in toughness. Scanning electron microscopy (SEM) characterization confirmed an enhanced interfacial bonding when functionalized MWNTs were integrated into epoxy/glass-fibre composites. The coefficient thermal expansion (CTE) of functionalized nanocomposites indicated a reduction of 25.2% compared with epoxy/glass-fibre composites. The desired improvement of electrical conductivities was also achieved. The multiscale composites indicated a way to leverage the benefits of CNTs and opened up new opportunities for high-performance multifunctional multiscale composites.

  2. Multifunctional Microtubule-Associated Proteins in Plants

    PubMed Central

    Krtková, Jana; Benáková, Martina; Schwarzerová, Kateřina

    2016-01-01

    Microtubules (MTs) are involved in key processes in plant cells, including cell division, growth and development. MT-interacting proteins modulate MT dynamics and organization, mediating functional and structural interaction of MTs with other cell structures. In addition to conventional microtubule-associated proteins (MAPs) in plants, there are many other MT-binding proteins whose primary function is not related to the regulation of MTs. This review focuses on enzymes, chaperones, or proteins primarily involved in other processes that also bind to MTs. The MT-binding activity of these multifunctional MAPs is often performed only under specific environmental or physiological conditions, or they bind to MTs only as components of a larger MT-binding protein complex. The involvement of multifunctional MAPs in these interactions may underlie physiological and morphogenetic events, e.g., under specific environmental or developmental conditions. Uncovering MT-binding activity of these proteins, although challenging, may contribute to understanding of the novel functions of the MT cytoskeleton in plant biological processes. PMID:27148302

  3. Designing multifunctional landscapes for forest conservation

    NASA Astrophysics Data System (ADS)

    Santika, Truly; Meijaard, Erik; Wilson, Kerrie A.

    2015-11-01

    A multifunctional landscape approach to forest protection has been advocated for tropical countries. Designing such landscapes necessitates that the role of different land uses in protecting forest be evaluated, along with the spatial interactions between land uses. However, such evaluations have been hindered by a lack of suitable analysis methodologies and data with fine spatial resolution over long time periods. We demonstrate the utility of a matching method with multiple categories to evaluate the role of alternative land uses in protecting forest. We also assessed the impact of land use change trajectories on the rate of deforestation. We employed data from Kalimantan (Indonesian Borneo) at three different time periods during 2000-2012 to illustrate our approach. Four single land uses (protected areas (PA), natural forest logging concessions (LC), timber plantation concessions (TC) and oil-palm plantation concessions (OC)) and two mixed land uses (mixed concessions and the overlap between concessions and PA) were assessed. The rate of deforestation was found to be lowest for PA, followed by LC. Deforestation rates for all land uses tended to be highest for locations that share the characteristics of areas in which TC or OC are located (e.g. degraded areas), suggesting that these areas are inherently more susceptible to deforestation due to foregone opportunities. Our approach provides important insights into how multifunctional landscapes can be designed to enhance the protection of biodiversity.

  4. Multifunctional porous silicon nanoparticles for cancer theranostics.

    PubMed

    Wang, Chang-Fang; Sarparanta, Mirkka P; Mäkilä, Ermei M; Hyvönen, Maija L K; Laakkonen, Pirjo M; Salonen, Jarno J; Hirvonen, Jouni T; Airaksinen, Anu J; Santos, Hélder A

    2015-04-01

    Nanomaterials provide a unique platform for the development of theranostic systems that combine diagnostic imaging modalities with a therapeutic payload in a single probe. In this work, dual-labeled iRGD-modified multifunctional porous silicon nanoparticles (PSi NPs) were prepared from dibenzocyclooctyl (DBCO) modified PSi NPs by strain-promoted azide-alkyne cycloaddition (SPAAC) click chemistry. Hydrophobic antiangiogenic drug, sorafenib, was loaded into the modified PSi NPs to enhance the drug dissolution rate and improve cancer therapy. Radiolabeling of the developed system with (111)In enabled the monitoring of the in vivo biodistribution of the nanocarrier by single photon emission computed tomography (SPECT) in an ectopic PC3-MM2 mouse xenograft model. Fluorescent labeling with Alexa Fluor 488 was used to determine the long-term biodistribution of the nanocarrier by immunofluorescence at the tissue level ex vivo. Modification of the PSi NPs with an iRGD peptide enhanced the tumor uptake of the NPs when administered intravenously. After intratumoral delivery the NPs were retained in the tumor, resulting in efficient tumor growth suppression with particle-loaded sorafenib compared to the free drug. The presented multifunctional PSi NPs highlight the utility of constructing a theranostic nanosystems for simultaneous investigations of the in vivo behavior of the nanocarriers and their drug delivery efficiency, facilitating the selection of the most promising materials for further NP development.

  5. Multifunctional Energy Storage and Conversion Devices.

    PubMed

    Huang, Yan; Zhu, Minshen; Huang, Yang; Pei, Zengxia; Li, Hongfei; Wang, Zifeng; Xue, Qi; Zhi, Chunyi

    2016-10-01

    Multifunctional energy storage and conversion devices that incorporate novel features and functions in intelligent and interactive modes, represent a radical advance in consumer products, such as wearable electronics, healthcare devices, artificial intelligence, electric vehicles, smart household, and space satellites, etc. Here, smart energy devices are defined to be energy devices that are responsive to changes in configurational integrity, voltage, mechanical deformation, light, and temperature, called self-healability, electrochromism, shape memory, photodetection, and thermal responsivity. Advisable materials, device designs, and performances are crucial for the development of energy electronics endowed with these smart functions. Integrating these smart functions in energy storage and conversion devices gives rise to great challenges from the viewpoint of both understanding the fundamental mechanisms and practical implementation. Current state-of-art examples of these smart multifunctional energy devices, pertinent to materials, fabrication strategies, and performances, are highlighted. In addition, current challenges and potential solutions from materials synthesis to device performances are discussed. Finally, some important directions in this fast developing field are considered to further expand their application.

  6. A Multifunctional Coating for Autonomous Corrosion Control

    NASA Technical Reports Server (NTRS)

    Calle, Luz M.; Hintze, Paul E.; Li, Wenyan; Buhrow, Jerry W.; Jolley, Scott T.

    2010-01-01

    Corrosion is a destructive process that often causes failure in metallic components and structures. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional, smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to control it. The multi-functionality of the coating is based on microencapsulation technology specifically designed for corrosion control applications. This design has, in addition to all the advantages of other existing microcapsules designs, the corrosion controlled release function that allows the delivery of corrosion indicators and inhibitors on demand only when and where they are needed. Corrosion indicators as well as corrosion inhibitors have been incorporated into the microcapsules, blended into several paint systems, and tested for corrosion detection and protection efficacy.

  7. Multifunctional Carbon Fibre Tapes for Automotive Composites

    NASA Astrophysics Data System (ADS)

    Koncherry, V.; Potluri, P.; Fernando, A.

    2017-04-01

    Cabon fibre composites are used where mechanical performance such as strength, stiffness and impact properties at low density is a critical parameter for engineering applications. Carbon fibre flat tape is one material which is traditionally used to manufacture three-dimensional composites in this area. Modifying the carbon fibre tape to incorporate other functions such as stealth, electromagnetic interference, shielding, de-icing, self-repair, energy storage, allows us to create multi-functional carbon fibre tape. Researchers have been developing such material and the technology for their manufacture in order to produce multifunctional carbon fibre based components more economically and efficiently. This paper presents the manufacturing process of a metallised carbon fibre material for a chopped fibre preforming process that uses electromagnets for preforming instead of traditional suction airflow fibre deposition. In addition, the paper further presents mechanical and magneto-static modelling that is carried out to investigate the bending properties of the material produced and its suitability for creating 3D preforms.

  8. Identification of multifunctional peptides from human milk.

    PubMed

    Mandal, Santi M; Bharti, Rashmi; Porto, William F; Gauri, Samiran S; Mandal, Mahitosh; Franco, Octavio L; Ghosh, Ananta K

    2014-06-01

    Pharmaceutical industries have renewed interest in screening multifunctional bioactive peptides as a marketable product in health care applications. In this context, several animal and plant peptides with potential bioactivity have been reported. Milk proteins and peptides have received much attention as a source of health-enhancing components to be incorporated into nutraceuticals and functional foods. By using this source, 24 peptides have been fractionated and purified from human milk using RP-HPLC. Multifunctional roles including antimicrobial, antioxidant and growth stimulating activity have been evaluated in all 24 fractions. Nevertheless, only four fractions show multiple combined activities among them. Using a proteomic approach, two of these four peptides have been identified as lactoferrin derived peptide and kappa casein short chain peptide. Lactoferrin derived peptide (f8) is arginine-rich and kappa casein derived (f12) peptide is proline-rich. Both peptides (f8 and f12) showed antimicrobial activities against both Gram-positive and Gram-negative bacteria. Fraction 8 (f8) exhibits growth stimulating activity in 3T3 cell line and f12 shows higher free radical scavenging activity in comparison to other fractions. Finally, both peptides were in silico evaluated and some insights into their mechanism of action were provided. Thus, results indicate that these identified peptides have multiple biological activities which are valuable for the quick development of the neonate and may be considered as potential biotechnological products for nutraceutical industry.

  9. Multifunctional Carbon Fibre Tapes for Automotive Composites

    NASA Astrophysics Data System (ADS)

    Koncherry, V.; Potluri, P.; Fernando, A.

    2016-11-01

    Cabon fibre composites are used where mechanical performance such as strength, stiffness and impact properties at low density is a critical parameter for engineering applications. Carbon fibre flat tape is one material which is traditionally used to manufacture three-dimensional composites in this area. Modifying the carbon fibre tape to incorporate other functions such as stealth, electromagnetic interference, shielding, de-icing, self-repair, energy storage, allows us to create multi-functional carbon fibre tape. Researchers have been developing such material and the technology for their manufacture in order to produce multifunctional carbon fibre based components more economically and efficiently. This paper presents the manufacturing process of a metallised carbon fibre material for a chopped fibre preforming process that uses electromagnets for preforming instead of traditional suction airflow fibre deposition. In addition, the paper further presents mechanical and magneto-static modelling that is carried out to investigate the bending properties of the material produced and its suitability for creating 3D preforms.

  10. Multisensory Stimulation Can Induce an Illusion of Larger Belly Size in Immersive Virtual Reality

    PubMed Central

    Normand, Jean-Marie; Giannopoulos, Elias; Spanlang, Bernhard; Slater, Mel

    2011-01-01

    Background Body change illusions have been of great interest in recent years for the understanding of how the brain represents the body. Appropriate multisensory stimulation can induce an illusion of ownership over a rubber or virtual arm, simple types of out-of-the-body experiences, and even ownership with respect to an alternate whole body. Here we use immersive virtual reality to investigate whether the illusion of a dramatic increase in belly size can be induced in males through (a) first person perspective position (b) synchronous visual-motor correlation between real and virtual arm movements, and (c) self-induced synchronous visual-tactile stimulation in the stomach area. Methodology Twenty two participants entered into a virtual reality (VR) delivered through a stereo head-tracked wide field-of-view head-mounted display. They saw from a first person perspective a virtual body substituting their own that had an inflated belly. For four minutes they repeatedly prodded their real belly with a rod that had a virtual counterpart that they saw in the VR. There was a synchronous condition where their prodding movements were synchronous with what they felt and saw and an asynchronous condition where this was not the case. The experiment was repeated twice for each participant in counter-balanced order. Responses were measured by questionnaire, and also a comparison of before and after self-estimates of belly size produced by direct visual manipulation of the virtual body seen from the first person perspective. Conclusions The results show that first person perspective of a virtual body that substitutes for the own body in virtual reality, together with synchronous multisensory stimulation can temporarily produce changes in body representation towards the larger belly size. This was demonstrated by (a) questionnaire results, (b) the difference between the self-estimated belly size, judged from a first person perspective, after and before the experimental

  11. Multifunctional non-viral gene vectors with enhanced stability, improved cellular and nuclear uptake capability, and increased transfection efficiency

    NASA Astrophysics Data System (ADS)

    Yang, Zhe; Jiang, Zhaozhong; Cao, Zhong; Zhang, Chao; Gao, Di; Luo, Xingen; Zhang, Xiaofang; Luo, Huiyan; Jiang, Qing; Liu, Jie

    2014-08-01

    We have developed a new multifunctional, non-viral gene delivery platform consisting of cationic poly(amine-co-ester) (PPMS) for DNA condensation, PEG shell for nanoparticle stabilization, poly(γ-glutamic acid) (γ-PGA) and mTAT (a cell-penetrating peptide) for accelerated cellular uptake, and a nuclear localization signal peptide (NLS) for enhanced intracellular transport of DNA to the nucleus. In vitro study showed that coating of the binary PPMS/DNA polyplex with γ-PGA promotes cellular uptake of the polyplex particles, particularly by γ-glutamyl transpeptidase (GGT)-positive cells through the GGT-mediated endocytosis pathway. Conjugating PEG to the γ-PGA led to the formation of a ternary PPMS/DNA/PGA-g-PEG polyplex with decreased positive charges on the surface of the polyplex particles and substantially higher stability in serum-containing aqueous medium. The cellular uptake rate was further improved by incorporating mTAT into the ternary polyplex system. Addition of the NLS peptide was designed to facilitate intracellular delivery of the plasmid to the nucleus--a rate-limiting step in the gene transfection process. As a result, compared with the binary PPMS/LucDNA polyplex, the new mTAT-quaternary PPMS/LucDNA/NLS/PGA-g-PEG-mTAT system exhibited reduced cytotoxicity, remarkably faster cellular uptake rate, and enhanced transport of DNA to the nucleus. All these advantageous functionalities contribute to the remarkable gene transfection efficiency of the mTAT-quaternary polyplex both in vitro and in vivo, which exceeds that of the binary polyplex and commercial Lipofectamine™ 2000/DNA lipoplex. The multifunctional mTAT-quaternary polyplex system with improved efficiency and reduced cytotoxicity represents a new type of promising non-viral vectors for the delivery of therapeutic genes to treat tumors.We have developed a new multifunctional, non-viral gene delivery platform consisting of cationic poly(amine-co-ester) (PPMS) for DNA condensation, PEG shell

  12. Biotic homogenization can decrease landscape-scale forest multifunctionality

    PubMed Central

    van der Plas, Fons; Manning, Pete; Soliveres, Santiago; Allan, Eric; Scherer-Lorenzen, Michael; Verheyen, Kris; Wirth, Christian; Zavala, Miguel A.; Ampoorter, Evy; Baeten, Lander; Barbaro, Luc; Bauhus, Jürgen; Benavides, Raquel; Benneter, Adam; Bonal, Damien; Bouriaud, Olivier; Bruelheide, Helge; Bussotti, Filippo; Carnol, Monique; Castagneyrol, Bastien; Charbonnier, Yohan; Coppi, Andrea; Bastias, Cristina C.; Dawud, Seid Muhie; De Wandeler, Hans; Domisch, Timo; Finér, Leena; Granier, André; Grossiord, Charlotte; Guyot, Virginie; Hättenschwiler, Stephan; Jactel, Hervé; Jaroszewicz, Bogdan; Joly, François-xavier; Jucker, Tommaso; Koricheva, Julia; Milligan, Harriet; Mueller, Sandra; Muys, Bart; Nguyen, Diem; Pollastrini, Martina; Ratcliffe, Sophia; Raulund-Rasmussen, Karsten; Selvi, Federico; Stenlid, Jan; Valladares, Fernando; Vesterdal, Lars; Zielínski, Dawid; Fischer, Markus

    2016-01-01

    Many experiments have shown that local biodiversity loss impairs the ability of ecosystems to maintain multiple ecosystem functions at high levels (multifunctionality). In contrast, the role of biodiversity in driving ecosystem multifunctionality at landscape scales remains unresolved. We used a comprehensive pan-European dataset, including 16 ecosystem functions measured in 209 forest plots across six European countries, and performed simulations to investigate how local plot-scale richness of tree species (α-diversity) and their turnover between plots (β-diversity) are related to landscape-scale multifunctionality. After accounting for variation in environmental conditions, we found that relationships between α-diversity and landscape-scale multifunctionality varied from positive to negative depending on the multifunctionality metric used. In contrast, when significant, relationships between β-diversity and landscape-scale multifunctionality were always positive, because a high spatial turnover in species composition was closely related to a high spatial turnover in functions that were supported at high levels. Our findings have major implications for forest management and indicate that biotic homogenization can have previously unrecognized and negative consequences for large-scale ecosystem multifunctionality. PMID:26979952

  13. Biotic homogenization can decrease landscape-scale forest multifunctionality.

    PubMed

    van der Plas, Fons; Manning, Pete; Soliveres, Santiago; Allan, Eric; Scherer-Lorenzen, Michael; Verheyen, Kris; Wirth, Christian; Zavala, Miguel A; Ampoorter, Evy; Baeten, Lander; Barbaro, Luc; Bauhus, Jürgen; Benavides, Raquel; Benneter, Adam; Bonal, Damien; Bouriaud, Olivier; Bruelheide, Helge; Bussotti, Filippo; Carnol, Monique; Castagneyrol, Bastien; Charbonnier, Yohan; Coomes, David Anthony; Coppi, Andrea; Bastias, Cristina C; Dawud, Seid Muhie; De Wandeler, Hans; Domisch, Timo; Finér, Leena; Gessler, Arthur; Granier, André; Grossiord, Charlotte; Guyot, Virginie; Hättenschwiler, Stephan; Jactel, Hervé; Jaroszewicz, Bogdan; Joly, François-Xavier; Jucker, Tommaso; Koricheva, Julia; Milligan, Harriet; Mueller, Sandra; Muys, Bart; Nguyen, Diem; Pollastrini, Martina; Ratcliffe, Sophia; Raulund-Rasmussen, Karsten; Selvi, Federico; Stenlid, Jan; Valladares, Fernando; Vesterdal, Lars; Zielínski, Dawid; Fischer, Markus

    2016-03-29

    Many experiments have shown that local biodiversity loss impairs the ability of ecosystems to maintain multiple ecosystem functions at high levels (multifunctionality). In contrast, the role of biodiversity in driving ecosystem multifunctionality at landscape scales remains unresolved. We used a comprehensive pan-European dataset, including 16 ecosystem functions measured in 209 forest plots across six European countries, and performed simulations to investigate how local plot-scale richness of tree species (α-diversity) and their turnover between plots (β-diversity) are related to landscape-scale multifunctionality. After accounting for variation in environmental conditions, we found that relationships between α-diversity and landscape-scale multifunctionality varied from positive to negative depending on the multifunctionality metric used. In contrast, when significant, relationships between β-diversity and landscape-scale multifunctionality were always positive, because a high spatial turnover in species composition was closely related to a high spatial turnover in functions that were supported at high levels. Our findings have major implications for forest management and indicate that biotic homogenization can have previously unrecognized and negative consequences for large-scale ecosystem multifunctionality.

  14. Severe multisensory speech integration deficits in high-functioning school-aged children with Autism Spectrum Disorder (ASD) and their resolution during early adolescence.

    PubMed

    Foxe, John J; Molholm, Sophie; Del Bene, Victor A; Frey, Hans-Peter; Russo, Natalie N; Blanco, Daniella; Saint-Amour, Dave; Ross, Lars A

    2015-02-01

    Under noisy listening conditions, visualizing a speaker's articulations substantially improves speech intelligibility. This multisensory speech integration ability is crucial to effective communication, and the appropriate development of this capacity greatly impacts a child's ability to successfully navigate educational and social settings. Research shows that multisensory integration abilities continue developing late into childhood. The primary aim here was to track the development of these abilities in children with autism, since multisensory deficits are increasingly recognized as a component of the autism spectrum disorder (ASD) phenotype. The abilities of high-functioning ASD children (n = 84) to integrate seen and heard speech were assessed cross-sectionally, while environmental noise levels were systematically manipulated, comparing them with age-matched neurotypical children (n = 142). Severe integration deficits were uncovered in ASD, which were increasingly pronounced as background noise increased. These deficits were evident in school-aged ASD children (5-12 year olds), but were fully ameliorated in ASD children entering adolescence (13-15 year olds). The severity of multisensory deficits uncovered has important implications for educators and clinicians working in ASD. We consider the observation that the multisensory speech system recovers substantially in adolescence as an indication that it is likely amenable to intervention during earlier childhood, with potentially profound implications for the development of social communication abilities in ASD children.

  15. Next-Generation Multifunctional Electrochromic Devices.

    PubMed

    Cai, Guofa; Wang, Jiangxin; Lee, Pooi See

    2016-08-16

    The rational design and exploration of electrochromic devices will find a wide range of applications in smart windows for energy-efficient buildings, low-power displays, self-dimming rear mirrors for automobiles, electrochromic e-skins, and so on. Electrochromic devices generally consist of multilayer structures with transparent conductors, electrochromic films, ion conductors, and ion storage films. Synthetic strategies and new materials for electrochromic films and transparent conductors, comprehensive electrochemical kinetic analysis, and novel device design are areas of active study worldwide. These are believed to be the key factors that will help to significantly improve the electrochromic performance and extend their application areas. In this Account, we present our strategies to design and fabricate electrochromic devices with high performance and multifunctionality. We first describe the synthetic strategies, in which a porous tungsten oxide (WO3) film with nearly ideal optical modulation and fast switching was prepared by a pulsed electrochemical deposition method. Multiple strategies, such as sol-gel/inkjet printing methods, hydrothermal/inkjet printing methods, and a novel hybrid transparent conductor/electrochromic layer have been developed to prepare high-performance electrochromic films. We then summarize the recent advances in transparent conductors and ion conductor layers, which play critial roles in electrochromic devices. Benefiting from the developments of soft transparent conductive substrates, highly deformable electrochromic devices that are flexible, foldable, stretchable, and wearable have been achieved. These emerging devices have great potential in applications such as soft displays, electrochromic e-skins, deformable electrochromic films, and so on. We finally present a concept of multifunctional smart glass, which can change its color to dynamically adjust the daylight and solar heat input of the building or protect the users' privacy

  16. Rate and Temporal Coding Convey Multisensory Information in Primary Sensory Cortices.

    PubMed

    Bieler, Malte; Sieben, Kay; Cichon, Nicole; Schildt, Sandra; Röder, Brigitte; Hanganu-Opatz, Ileana L

    2017-01-01

    Optimal behavior and survival result from integration of information across sensory systems. Modulation of network activity at the level of primary sensory cortices has been identified as a mechanism of cross-modal integration, yet its cellular substrate is still poorly understood. Here, we uncover the mechanisms by which individual neurons in primary somatosensory (S1) and visual (V1) cortices encode visual-tactile stimuli. For this, simultaneous extracellular recordings were performed from all layers of the S1 barrel field and V1 in Brown Norway rats in vivo and units were clustered and assigned to pyramidal neurons (PYRs) and interneurons (INs). We show that visual-tactile stimulation modulates the firing rate of a relatively low fraction of neurons throughout all cortical layers. Generally, it augments the firing of INs and decreases the activity of PYRs. Moreover, bimodal stimulation shapes the timing of neuronal firing by strengthening the phase-coupling between neuronal discharge and theta-beta band network oscillations as well as by modulating spiking onset. Sparse direct axonal projections between neurons in S1 and V1 seem to time the spike trains between the two cortical areas and, thus, may act as a substrate of cross-modal modulation. These results indicate that few cortical neurons mediate multisensory effects in primary sensory areas by directly encoding cross-modal information by their rate and timing of firing.

  17. A systematic review of multisensory cognitive-affective integration in schizophrenia.

    PubMed

    Tseng, Huai-Hsuan; Bossong, Matthijs G; Modinos, Gemma; Chen, Kuan-Ming; McGuire, Philip; Allen, Paul

    2015-08-01

    The etymology of schizophrenia implies poor functional integration of sensory, cognitive and affective processes. Multisensory integration (MSI) is a spontaneous perceptual-cognitive process by which relevant information from multiple sensory modalities is extracted to generate a holistic experience. Deficits in MSI may hinder prompt and appropriate behavioural responses in a complex and transient environment. Despite extensive investigation of sensory, cognitive and affective processing in patients with schizophrenia, little is known about how MSI is affected in the illness. We systemically searched the PubMed electronic database and reviewed twenty-nine behavioural and neuroimaging studies examining MSI in patients with schizophrenia. The available evidence indicates impaired MSI for non-emotional stimuli in schizophrenia, especially for linguistic information. There is also evidence for altered MSI for emotional stimuli, although findings are inconsistent and may be modality-specific. Brain functional alterations in the superior temporal cortex and inferior frontal cortex appear to underlie the deficits in both non-emotional and emotional MSI. The limitations of the experimental paradigms used and directions for future research are also discussed.

  18. Enhanced integration of multisensory body information by proximity to "habitual action space".

    PubMed

    Dempsey-Jones, Harriet; Kritikos, Ada

    2017-04-01

    Previous research suggests integration of visual and somatosensory inputs is enhanced within reaching (peripersonal) space. In such experiments, somatosensory inputs are presented on the body while visual inputs are moved relatively closer to, or further from the body. It is unclear, therefore, whether enhanced integration in "peripersonal space" is truly due to proximity of visual inputs to the body space, or, simply the distance between the inputs (which also affects integration). Using a modified induction of the rubber hand illusion, here we measured proprioceptive drift as an index of visuosomatosensory integration when distance between the two inputs was constrained, and absolute distance from the body was varied. Further, we investigated whether integration varies with proximity of inputs to the habitual action space of the arm-rather than the actual arm itself. In Experiment 1, integration was enhanced with inputs proximal to habitual action space, and reduced with lateral distance from this space. This was not attributable to an attentional or perceptual bias of external space because the pattern of proprioceptive drift was opposite for left and right hand illusions, that is, consistently maximal at the shoulder of origin (Experiment 2). We conclude that habitual patterns of action modulate visuosomatosensory integration. It appears multisensory integration is modulated in locations of space that are functionally relevant for behavior, whether an actual body part resides within that space or not. (PsycINFO Database Record

  19. Multisensory integration in the developing tectum is constrained by the balance of excitation and inhibition

    PubMed Central

    Felch, Daniel L; Khakhalin, Arseny S; Aizenman, Carlos D

    2016-01-01

    Multisensory integration (MSI) is the process that allows the brain to bind together spatiotemporally congruent inputs from different sensory modalities to produce single salient representations. While the phenomenology of MSI in vertebrate brains is well described, relatively little is known about cellular and synaptic mechanisms underlying this phenomenon. Here we use an isolated brain preparation to describe cellular mechanisms underlying development of MSI between visual and mechanosensory inputs in the optic tectum of Xenopus tadpoles. We find MSI is highly dependent on the temporal interval between crossmodal stimulus pairs. Over a key developmental period, the temporal window for MSI significantly narrows and is selectively tuned to specific interstimulus intervals. These changes in MSI correlate with developmental increases in evoked synaptic inhibition, and inhibitory blockade reverses observed developmental changes in MSI. We propose a model in which development of recurrent inhibition mediates development of temporal aspects of MSI in the tectum. DOI: http://dx.doi.org/10.7554/eLife.15600.001 PMID:27218449

  20. Objective Fidelity Evaluation in Multisensory Virtual Environments: Auditory Cue Fidelity in Flight Simulation

    PubMed Central

    Meyer, Georg F.; Wong, Li Ting; Timson, Emma; Perfect, Philip; White, Mark D.

    2012-01-01

    We argue that objective fidelity evaluation of virtual environments, such as flight simulation, should be human-performance-centred and task-specific rather than measure the match between simulation and physical reality. We show how principled experimental paradigms and behavioural models to quantify human performance in simulated environments that have emerged from research in multisensory perception provide a framework for the objective evaluation of the contribution of individual cues to human performance measures of fidelity. We present three examples in a flight simulation environment as a case study: Experiment 1: Detection and categorisation of auditory and kinematic motion cues; Experiment 2: Performance evaluation in a target-tracking task; Experiment 3: Transferrable learning of auditory motion cues. We show how the contribution of individual cues to human performance can be robustly evaluated for each task and that the contribution is highly task dependent. The same auditory cues that can be discriminated and are optimally integrated in experiment 1, do not contribute to target-tracking performance in an in-flight refuelling simulation without training, experiment 2. In experiment 3, however, we demonstrate that the auditory cue leads to significant, transferrable, performance improvements with training. We conclude that objective fidelity evaluation requires a task-specific analysis of the contribution of individual cues. PMID:22957068

  1. A cooperative function for multisensory stimuli in the induction of approach behavior of a potential mate

    PubMed Central

    Ågmo, Anders

    2017-01-01

    Intrasexual competition is an important element of natural selection in which the most attractive conspecific has a considerable reproductive advantage over the others. The conspecifics that are approached first often become the preferred mate partners, and could thus from a biological perspective have a reproductive advantage. This underlines the importance of the initial approach and raises the question of what induces this approach, or what makes a conspecific attractive. Identification of the sensory modalities crucial for the activation of approach is necessary for elucidating the central nervous processes involved in the activation of sexual motivation and eventually copulatory behavior. The initial approach to a potential mate depends on distant stimuli in the modalities of audition, olfaction, vision, and other undefined characteristics. This study investigated the role of the different modalities and the combination of these modalities in the sexual incentive value of a female rat. This study provides evidence that the presence of a single-sensory stimulus with one modality (olfaction, vision, or ‘others’, but not audition) is sufficient to attenuate the preference for a social contact with a male rat. However, a multisensory stimulus of multiple modalities is necessary to induce preference for the stimulus over social contact to a level of an intact receptive female. The initial approach behavior, therefore, seems to be induced by the combination of at least two modalities among which olfaction is crucial. This suggests that there is a cooperative function for the different modalities in the induction of approach behavior of a potential mate. PMID:28306729

  2. A Self-Synthesis Approach to Perceptual Learning for Multisensory Fusion in Robotics

    PubMed Central

    Axenie, Cristian; Richter, Christoph; Conradt, Jörg

    2016-01-01

    Biological and technical systems operate in a rich multimodal environment. Due to the diversity of incoming sensory streams a system perceives and the variety of motor capabilities a system exhibits there is no single representation and no singular unambiguous interpretation of such a complex scene. In this work we propose a novel sensory processing architecture, inspired by the distributed macro-architecture of the mammalian cortex. The underlying computation is performed by a network of computational maps, each representing a different sensory quantity. All the different sensory streams enter the system through multiple parallel channels. The system autonomously associates and combines them into a coherent representation, given incoming observations. These processes are adaptive and involve learning. The proposed framework introduces mechanisms for self-creation and learning of the functional relations between the computational maps, encoding sensorimotor streams, directly from the data. Its intrinsic scalability, parallelisation, and automatic adaptation to unforeseen sensory perturbations make our approach a promising candidate for robust multisensory fusion in robotic systems. We demonstrate this by applying our model to a 3D motion estimation on a quadrotor. PMID:27775621

  3. Multi-sensory landscape assessment: the contribution of acoustic perception to landscape evaluation.

    PubMed

    Gan, Yonghong; Luo, Tao; Breitung, Werner; Kang, Jian; Zhang, Tianhai

    2014-12-01

    In this paper, the contribution of visual and acoustic preference to multi-sensory landscape evaluation was quantitatively compared. The real landscapes were treated as dual-sensory ambiance and separated into visual landscape and soundscape. Both were evaluated by 63 respondents in laboratory conditions. The analysis of the relationship between respondent's visual and acoustic preference as well as their respective contribution to landscape preference showed that (1) some common attributes are universally identified in assessing visual, aural and audio-visual preference, such as naturalness or degree of human disturbance; (2) with acoustic and visual preferences as variables, a multi-variate linear regression model can satisfactorily predict landscape preference (R(2 )= 0.740), while the coefficients of determination for a unitary linear regression model were 0.345 and 0.720 for visual and acoustic preference as predicting factors, respectively; (3) acoustic preference played a much more important role in landscape evaluation than visual preference in this study (the former is about 4.5 times of the latter), which strongly suggests a rethinking of the role of soundscape in environment perception research and landscape planning practice.

  4. Rate and Temporal Coding Convey Multisensory Information in Primary Sensory Cortices

    PubMed Central

    Sieben, Kay; Cichon, Nicole; Schildt, Sandra; Röder, Brigitte

    2017-01-01

    Abstract Optimal behavior and survival result from integration of information across sensory systems. Modulation of network activity at the level of primary sensory cortices has been identified as a mechanism of cross-modal integration, yet its cellular substrate is still poorly understood. Here, we uncover the mechanisms by which individual neurons in primary somatosensory (S1) and visual (V1) cortices encode visual-tactile stimuli. For this, simultaneous extracellular recordings were performed from all layers of the S1 barrel field and V1 in Brown Norway rats in vivo and units were clustered and assigned to pyramidal neurons (PYRs) and interneurons (INs). We show that visual-tactile stimulation modulates the firing rate of a relatively low fraction of neurons throughout all cortical layers. Generally, it augments the firing of INs and decreases the activity of PYRs. Moreover, bimodal stimulation shapes the timing of neuronal firing by strengthening the phase-coupling between neuronal discharge and theta–beta band network oscillations as well as by modulating spiking onset. Sparse direct axonal projections between neurons in S1 and V1 seem to time the spike trains between the two cortical areas and, thus, may act as a substrate of cross-modal modulation. These results indicate that few cortical neurons mediate multisensory effects in primary sensory areas by directly encoding cross-modal information by their rate and timing of firing. PMID:28374008

  5. Rheotaxis of Larval Zebrafish: Behavioral Study of a Multi-Sensory Process

    PubMed Central

    Olive, Raphaël; Wolf, Sébastien; Dubreuil, Alexis; Bormuth, Volker; Debrégeas, Georges; Candelier, Raphaël

    2016-01-01

    Awake animals unceasingly perceive sensory inputs with great variability of nature and intensity, and understanding how the nervous system manages this continuous flow of diverse information to get a coherent representation of the environment is arguably a central question in systems neuroscience. Rheotaxis, the ability shared by most aquatic species to orient toward a current and swim to hold position, is an innate and robust multi-sensory behavior that is known to involve the lateral line and visual systems. To facilitate the neuroethological study of rheotaxic behavior in larval zebrafish we developed an assay for freely swimming larvae that allows for high experimental throughtput, large statistic and a fine description of the behavior. We show that there exist a clear transition from exploration to counterflow swim, and by changing the sensory modalities accessible to the fishes (visual only, lateral line only or both) and comparing the swim patterns at different ages we were able to detect and characterize two different mechanisms for position holding, one mediated by the lateral line and one mediated by the visual system. We also found that when both sensory modalities are accessible the visual system overshadows the lateral line, suggesting that at the larval stage the sensory inputs are not merged to finely tune the behavior but that redundant information pathways may be used as functional fallbacks. PMID:26941620

  6. Electrosensory capture during multisensory discrimination of nearby objects in the weakly electric fish Gnathonemus petersii

    PubMed Central

    Schumacher, Sarah; Burt de Perera, Theresa; von der Emde, Gerhard

    2017-01-01

    Animal multisensory systems are able to cope with discrepancies in information provided by individual senses by integrating information using a weighted average of the sensory inputs. Such sensory weighting often leads to a dominance of a certain sense during particular tasks and conditions, also called sensory capture. Here we investigated the interaction of vision and active electrolocation during object discrimination in the weakly electric fish Gnathonemus petersii. Fish were trained to discriminate between two objects using both senses and were subsequently tested using either only vision or only the active electric sense. We found that at short range the electric sense dominates over vision, leading to a decreased ability to discriminate between objects visually when vision and electrolocation provide conflicting information. In line with visual capture in humans, we call this dominance of the electric sense electrosensory capture. Further, our results suggest that the fish are able to exploit the advantages of multiple senses using vision and electrolocation redundantly, synergistically and complementarily. Together our results show that by providing similar information about the environment on different spatial scales, vision and the electric sense of G. petersii are well attuned to each other producing a robust and flexible percept. PMID:28257127

  7. Vocalization-whisking coordination and multisensory integration of social signals in rat auditory cortex.

    PubMed

    Rao, Rajnish P; Mielke, Falk; Bobrov, Evgeny; Brecht, Michael

    2014-12-08

    Social interactions involve multi-modal signaling. Here, we study interacting rats to investigate audio-haptic coordination and multisensory integration in the auditory cortex. We find that facial touch is associated with an increased rate of ultrasonic vocalizations, which are emitted at the whisking rate (∼8 Hz) and preferentially initiated in the retraction phase of whisking. In a small subset of auditory cortex regular-spiking neurons, we observed excitatory and heterogeneous responses to ultrasonic vocalizations. Most fast-spiking neurons showed a stronger response to calls. Interestingly, facial touch-induced inhibition in the primary auditory cortex and off-responses after termination of touch were twofold stronger than responses to vocalizations. Further, touch modulated the responsiveness of auditory cortex neurons to ultrasonic vocalizations. In summary, facial touch during social interactions involves precisely orchestrated calling-whisking patterns. While ultrasonic vocalizations elicited a rather weak population response from the regular spikers, the modulation of neuronal responses by facial touch was remarkably strong.

  8. Effects of multisensory and motor stimulation on the behavior of people with dementia.

    PubMed

    Sposito, Giovana; Barbosa, Ana; Figueiredo, Daniela; Yassuda, Mônica Sanches; Marques, Alda

    2015-06-25

    A quasi-experimental study using a pre-posttest design was conducted in four aged care facilities to assess the effects of a person-centred care (PCC) multisensory stimulation (MSS) and motor stimulation (MS) program, implemented by direct care workers, on the behaviors of residents with dementia. Data were collected at baseline and after the intervention through video recordings of morning care routines. Forty-five residents with moderate and severe dementia participated in the study. A total of 266 morning care routines were recorded. The frequency and duration of a list of behaviors were analyzed. The frequency of engagement in task decreased significantly (p = .002) however, its duration increased (p = .039). The duration of gaze directed at direct care workers improved significantly (p = .014) and the frequency of closed eyes decreased (p = .046). There was a significant decrease in the frequency of the expression of sadness. These results support the implementation of PCC-MSS and MS programs as they may stimulate residents' behaviors.

  9. Bilateral temporal cortex transcranial direct current stimulation worsens male performance in a multisensory integration task.

    PubMed

    Lapenta, Olivia Morgan; Fregni, Felipe; Oberman, Lindsay M; Boggio, Paulo Sergio

    2012-10-11

    Somatosensory integration is a critical cognitive function for human social interaction. Though somatosensory integration has been highly explored in cognitive studies; only a few studies have explored focal modulation of cortical excitability using a speech perception paradigm. In the current study, we aimed to investigate the effects of tDCS applied over the temporal cortex of healthy subjects during a go-no-go task in which stimuli were shapes and non-words. Twenty-eight subjects were randomized to receive cathodal, anodal or sham tDCS bilaterally over the superior temporal cortex (the reference electrode was on deltoid) in a counterbalanced order. The effects on judgment of congruency between shapes and non-words in healthy volunteers were measured by a go-no-go task. Our findings show a significant modification of performance according to the polarity of stimulation, task and subject gender. We found that men performed worse on the no-go condition for congruent stimuli during cathodal tDCS. For reaction time, on the other hand, there was a similar effect for anodal and cathodal stimulation. There were significantly faster responses on incongruent trials during both anodal and cathodal tDCS. Along with previous literature showing gender differences in tasks associated with speech perception, the findings of this study provide additional evidence suggesting that men may have a more focal and restricted neural processing in this multisensory integration task.

  10. Distributed multisensory integration in a recurrent network model through supervised learning

    NASA Astrophysics Data System (ADS)

    Wang, He; Wong, K. Y. Michael

    Sensory integration between different modalities has been extensively studied. It is suggested that the brain integrates signals from different modalities in a Bayesian optimal way. However, how the Bayesian rule is implemented in a neural network remains under debate. In this work we propose a biologically plausible recurrent network model, which can perform Bayesian multisensory integration after trained by supervised learning. Our model is composed of two modules, each for one modality. We assume that each module is a recurrent network, whose activity represents the posterior distribution of each stimulus. The feedforward input on each module is the likelihood of each modality. Two modules are integrated through cross-links, which are feedforward connections from the other modality, and reciprocal connections, which are recurrent connections between different modules. By stochastic gradient descent, we successfully trained the feedforward and recurrent coupling matrices simultaneously, both of which resembles the Mexican-hat. We also find that there are more than one set of coupling matrices that can approximate the Bayesian theorem well. Specifically, reciprocal connections and cross-links will compensate each other if one of them is removed. Even though trained with two inputs, the network's performance with only one input is in good accordance with what is predicted by the Bayesian theorem.

  11. Electrosensory capture during multisensory discrimination of nearby objects in the weakly electric fish Gnathonemus petersii.

    PubMed

    Schumacher, Sarah; Burt de Perera, Theresa; von der Emde, Gerhard

    2017-03-03

    Animal multisensory systems are able to cope with discrepancies in information provided by individual senses by integrating information using a weighted average of the sensory inputs. Such sensory weighting often leads to a dominance of a certain sense during particular tasks and conditions, also called sensory capture. Here we investigated the interaction of vision and active electrolocation during object discrimination in the weakly electric fish Gnathonemus petersii. Fish were trained to discriminate between two objects using both senses and were subsequently tested using either only vision or only the active electric sense. We found that at short range the electric sense dominates over vision, leading to a decreased ability to discriminate between objects visually when vision and electrolocation provide conflicting information. In line with visual capture in humans, we call this dominance of the electric sense electrosensory capture. Further, our results suggest that the fish are able to exploit the advantages of multiple senses using vision and electrolocation redundantly, synergistically and complementarily. Together our results show that by providing similar information about the environment on different spatial scales, vision and the electric sense of G. petersii are well attuned to each other producing a robust and flexible percept.

  12. A Self-Synthesis Approach to Perceptual Learning for Multisensory Fusion in Robotics.

    PubMed

    Axenie, Cristian; Richter, Christoph; Conradt, Jörg

    2016-10-20

    Biological and technical systems operate in a rich multimodal environment. Due to the diversity of incoming sensory streams a system perceives and the variety of motor capabilities a system exhibits there is no single representation and no singular unambiguous interpretation of such a complex scene. In this work we propose a novel sensory processing architecture, inspired by the distributed macro-architecture of the mammalian cortex. The underlying computation is performed by a network of computational maps, each representing a different sensory quantity. All the different sensory streams enter the system through multiple parallel channels. The system autonomously associates and combines them into a coherent representation, given incoming observations. These processes are adaptive and involve learning. The proposed framework introduces mechanisms for self-creation and learning of the functional relations between the computational maps, encoding sensorimotor streams, directly from the data. Its intrinsic scalability, parallelisation, and automatic adaptation to unforeseen sensory perturbations make our approach a promising candidate for robust multisensory fusion in robotic systems. We demonstrate this by applying our model to a 3D motion estimation on a quadrotor.

  13. Telling the right hand from the left hand: multisensory integration, not motor imagery, solves the problem.

    PubMed

    Viswanathan, Shivakumar; Fritz, Courtney; Grafton, Scott T

    2012-06-01

    Judging the laterality of a hand seen at unanticipated orientations evokes a robust feeling of bodily movement, even though no movement is produced. In two experiments, we tested a novel hypothesis to explain this phenomenon: A hand's laterality is determined via a multisensory binding of the visual representation of the seen hand and a proprioceptive representation of the observer's felt hand, and the felt "movement" is an obligatory aftereffect of intersensory recalibration. Consistent with the predictions implied by such a cross-modal mechanism, our results in Experiment 1 showed that manipulating observers' selective attention can evoke illusory feelings of movement in the "wrong" hand (i.e., the hand whose laterality does not match that of the stimulus). In Experiment 2, these illusions were readily extinguished in conditions in which binding was predicted to fail, a result indicating that cross-modal binding was necessary to produce them. These results are not explained by imagery, a mechanism widely assumed to account for how hand laterality is identified.

  14. Susceptibility to a multisensory speech illusion in older persons is driven by perceptual processes

    PubMed Central

    Setti, Annalisa; Burke, Kate E.; Kenny, RoseAnne; Newell, Fiona N.

    2013-01-01

    Recent studies suggest that multisensory integration is enhanced in older adults but it is not known whether this enhancement is solely driven by perceptual processes or affected by cognitive processes. Using the “McGurk illusion,” in Experiment 1 we found that audio-visual integration of incongruent audio-visual words was higher in older adults than in younger adults, although the recognition of either audio- or visual-only presented words was the same across groups. In Experiment 2 we tested recall of sentences within which an incongruent audio-visual speech word was embedded. The overall semantic meaning of the sentence was compatible with either one of the unisensory components of the target word and/or with the illusory percept. Older participants recalled more illusory audio-visual words in sentences than younger adults, however, there was no differential effect of word compatibility on recall for the two groups. Our findings suggest that the relatively high susceptibility to the audio-visual speech illusion in older participants is due more to perceptual than cognitive processing. PMID:24027544

  15. The Impact of Feedback on the Different Time Courses of Multisensory Temporal Recalibration

    PubMed Central

    Noel, Jean-Paul; Wallace, Mark T.

    2017-01-01

    The capacity to rapidly adjust perceptual representations confers a fundamental advantage when confronted with a constantly changing world. Unexplored is how feedback regarding sensory judgments (top-down factors) interacts with sensory statistics (bottom-up factors) to drive long- and short-term recalibration of multisensory perceptual representations. Here, we examined the time course of both cumulative and rapid temporal perceptual recalibration for individuals completing an audiovisual simultaneity judgment task in which they were provided with varying degrees of feedback. We find that in the presence of feedback (as opposed to simple sensory exposure) temporal recalibration is more robust. Additionally, differential time courses are seen for cumulative and rapid recalibration dependent upon the nature of the feedback provided. Whereas cumulative recalibration effects relied more heavily on feedback that informs (i.e., negative feedback) rather than confirms (i.e., positive feedback) the judgment, rapid recalibration shows the opposite tendency. Furthermore, differential effects on rapid and cumulative recalibration were seen when the reliability of feedback was altered. Collectively, our findings illustrate that feedback signals promote and sustain audiovisual recalibration over the course of cumulative learning and enhance rapid trial-to-trial learning. Furthermore, given the differential effects seen for cumulative and rapid recalibration, these processes may function via distinct mechanisms. PMID:28316841

  16. Multifunctional Carbon Nanostructures for Advanced Energy Storage Applications

    PubMed Central

    Wang, Yiran; Wei, Huige; Lu, Yang; Wei, Suying; Wujcik, Evan K.; Guo, Zhanhu

    2015-01-01

    Carbon nanostructures—including graphene, fullerenes, etc.—have found applications in a number of areas synergistically with a number of other materials.These multifunctional carbon nanostructures have recently attracted tremendous interest for energy storage applications due to their large aspect ratios, specific surface areas, and electrical conductivity. This succinct review aims to report on the recent advances in energy storage applications involving these multifunctional carbon nanostructures. The advanced design and testing of multifunctional carbon nanostructures for energy storage applications—specifically, electrochemical capacitors, lithium ion batteries, and fuel cells—are emphasized with comprehensive examples. PMID:28347034

  17. Multifunctional iron oxide nanoparticles for biomedical applications

    NASA Astrophysics Data System (ADS)

    Bloemen, M.; Denis, C.; Van Stappen, T.; De Meester, L.; Geukens, N.; Gils, A.; Verbiest, T.

    2015-03-01

    Multifunctional nanoparticles have attracted a lot of attention since they can combine interesting properties like magnetism, fluorescence or plasmonic effects. As a core material, iron oxide nanoparticles have been the subject of intensive research. These cost-effective and non-toxic particles are used nowadays in many applications. We developed a heterobifunctional PEG ligand that can be used to introduce functional groups (carboxylic acids) onto the surface of the NP. Via click chemistry, a siloxane functionality was added to this ligand, for a subsequent covalent ligand exchange reaction. The functionalized nanoparticles have an excellent colloidal stability in complex environments like buffers and serum or plasma. Antibodies were coupled to the introduced carboxylic acids and these NP-antibody bioconjugates were brought into contact with Legionella bacteria for magnetic separation experiments.

  18. Hybrid metamaterials for electrically triggered multifunctional control

    PubMed Central

    Liu, Liu; Kang, Lei; Mayer, Theresa S.; Werner, Douglas H.

    2016-01-01

    Despite the exotic material properties that have been demonstrated to date, practical examples of versatile metamaterials remain exceedingly rare. The concept of metadevices has been proposed in the context of hybrid metamaterial composites: systems in which active materials are introduced to advance tunability, switchability and nonlinearity. In contrast to the successful hybridizations seen at lower frequencies, there has been limited exploration into plasmonic and photonic nanostructures due to the lack of available optical materials with non-trivial activity, together with difficulties in regulating responses to external forces in an integrated manner. Here, by presenting a series of proof-of-concept studies on electrically triggered functionalities, we demonstrate a vanadium dioxide integrated photonic metamaterial as a transformative platform for multifunctional control. The proposed hybrid metamaterial integrated with transition materials represents a major step forward by providing a universal approach to creating self-sufficient and highly versatile nanophotonic systems. PMID:27807342

  19. 3D Multifunctional Ablative Thermal Protection System

    NASA Technical Reports Server (NTRS)

    Feldman, Jay; Venkatapathy, Ethiraj; Wilkinson, Curt; Mercer, Ken

    2015-01-01

    NASA is developing the Orion spacecraft to carry astronauts farther into the solar system than ever before, with human exploration of Mars as its ultimate goal. One of the technologies required to enable this advanced, Apollo-shaped capsule is a 3-dimensional quartz fiber composite for the vehicle's compression pad. During its mission, the compression pad serves first as a structural component and later as an ablative heat shield, partially consumed on Earth re-entry. This presentation will summarize the development of a new 3D quartz cyanate ester composite material, 3-Dimensional Multifunctional Ablative Thermal Protection System (3D-MAT), designed to meet the mission requirements for the Orion compression pad. Manufacturing development, aerothermal (arc-jet) testing, structural performance, and the overall status of material development for the 2018 EM-1 flight test will be discussed.

  20. Intelligent multifunction myoelectric control of hand prostheses.

    PubMed

    Light, C M; Chappell, P H; Hudgins, B; Engelhart, K

    2002-01-01

    Intuitive myoelectric prosthesis control is difficult to achieve due to the absence of proprioceptive feedback, which forces the user to monitor grip pressure by visual information. Existing myoelectric hand prostheses form a single degree of freedom pincer motion that inhibits the stable prehension of a range of objects. Multi-axis hands may address this lack of functionality, but as with multifunction devices in general, serve to increase the cognitive burden on the user. Intelligent hierarchical control of multiple degree-of-freedom hand prostheses has been used to reduce the need for visual feedback by automating the grasping process. This paper presents a hybrid controller that has been developed to enable different prehensile functions to be initiated directly from the user's myoelectric signal. A digital signal processor (DSP) regulates the grip pressure of a new six-degree-of-freedom hand prosthesis thereby ensuring secure prehension without continuous visual feedback.

  1. Modeling phase noise in multifunction subassemblies.

    PubMed

    Driscoll, Michael

    2012-03-01

    Obtaining requisite phase noise performance in hardware containing multifunction circuitry requires accurate modeling of the phase noise characteristics of each signal path component, including both absolute (oscillator) and residual (non-oscillator) circuit contributors. This includes prediction of both static and vibration-induced phase noise. The model (usually in spreadsheet form) is refined as critical components are received and evaluated. Additive (KTBF) phase noise data can be reasonably estimated, based on device drive level and noise figure. However, accurate determination of component near-carrier (multiplicative) and vibration-induced noise usually must be determined via measurement. The model should also include the effects of noise introduced by IC voltage regulators and properly discriminate between common versus independent signal path residual noise contributors. The modeling can be easily implemented using a spreadsheet.

  2. Multifunctional carbon nanohorn complexes for cancer treatment.

    PubMed

    Chechetka, Svetlana A; Pichon, Benoit; Zhang, Minfang; Yudasaka, Masako; Bégin-Colin, Sylvie; Bianco, Alberto; Miyako, Eijiro

    2015-01-01

    Multifunctional carbon nanohorn (CNH) complexes were synthesized using oxidized CNH, magnetite (MAG) nanoparticles, and polyethyleneimine (PEI). The ferromagnetic MAG nanoparticles were loaded onto CNH (MAG-CNH) using iron(II) acetate and subsequent heat treatment. Chemical functionalization of the MAG-CNH complexes with PEI improved their water-dispersibility and allowed further conjugation with a fluorophore. The application of an external magnetic field significantly intensified the targeted vectorization of CNH complexes into human cervical cancer (HeLa) cells. Following cell uptake, laser irradiation of the cells showed a significant enhancement in the photothermal effects of CNHs leading to cell death. We have confirmed that the photothermal properties and ferromagnetic characteristics of CNH complexes show efficient cell elimination. The present study is an essential step toward the development of an innovative cancer therapy and a highly sensitive detection of cancer cells at the single-cell level.

  3. On Multifunctional Collaborative Methods in Engineering Science

    NASA Technical Reports Server (NTRS)

    Ransom, Jonathan B.

    2001-01-01

    Multifunctional methodologies and analysis procedures are formulated for interfacing diverse subdomain idealizations including multi-fidelity modeling methods and multi-discipline analysis methods. These methods, based on the method of weighted residuals, ensure accurate compatibility of primary and secondary variables across the subdomain interfaces. Methods are developed using diverse mathematical modeling (i.e., finite difference and finite element methods) and multi-fidelity modeling among the subdomains. Several benchmark scalar-field and vector-field problems in engineering science are presented with extensions to multidisciplinary problems. Results for all problems presented are in overall good agreement with the exact analytical solution or the reference numerical solution. Based on the results, the integrated modeling approach using the finite element method for multi-fidelity discretization among the subdomains is identified as most robust. The multiple method approach is advantageous when interfacing diverse disciplines in which each of the method's strengths are utilized.

  4. High Performance Multifunctional Carbon Nanotube Fibers

    NASA Astrophysics Data System (ADS)

    Dalton, Alan; Collins, Steve; Munoz, Edgar; Razal, Joselito; Ebron, Von; Ferraris, John; Baughman, Ray

    2003-03-01

    Exploiting the extraordinary properties of carbon nanotubes has remained somewhat elusive due to the inability to process the as produced insoluble soot into functional macroscopic assemblies. To this end we have developed a simple but effective method to produce continuous, homogeneous fibers containing carbon nanotubes having as-spun mechanical properties that compare very favorably to recognized synthetic and natural "super fibers" such as Kevlar and spider silk. By using novel spinning apparatus, spinning solutions, and spinning coagulants, we have spun nanotube fibers having record lengths, record tensile strengths, and having an energy-to-break (toughness) higher than any material that we have found. As an example of the potential multi-functionalities of our fibers, we have fabricated fiber supercapacitors, which we weave into textiles.

  5. Multiscale Multifunctional Progressive Fracture of Composite Structures

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.; Minnetyan, L.

    2012-01-01

    A new approach is described for evaluating fracture in composite structures. This approach is independent of classical fracture mechanics parameters like fracture toughness. It relies on computational simulation and is programmed in a stand-alone integrated computer code. It is multiscale, multifunctional because it includes composite mechanics for the composite behavior and finite element analysis for predicting the structural response. It contains seven modules; layered composite mechanics (micro, macro, laminate), finite element, updating scheme, local fracture, global fracture, stress based failure modes, and fracture progression. The computer code is called CODSTRAN (Composite Durability Structural ANalysis). It is used in the present paper to evaluate the global fracture of four composite shell problems and one composite built-up structure. Results show that the composite shells. Global fracture is enhanced when internal pressure is combined with shear loads. The old reference denotes that nothing has been added to this comprehensive report since then.

  6. Hybrid metamaterials for electrically triggered multifunctional control

    NASA Astrophysics Data System (ADS)

    Liu, Liu; Kang, Lei; Mayer, Theresa S.; Werner, Douglas H.

    2016-10-01

    Despite the exotic material properties that have been demonstrated to date, practical examples of versatile metamaterials remain exceedingly rare. The concept of metadevices has been proposed in the context of hybrid metamaterial composites: systems in which active materials are introduced to advance tunability, switchability and nonlinearity. In contrast to the successful hybridizations seen at lower frequencies, there has been limited exploration into plasmonic and photonic nanostructures due to the lack of available optical materials with non-trivial activity, together with difficulties in regulating responses to external forces in an integrated manner. Here, by presenting a series of proof-of-concept studies on electrically triggered functionalities, we demonstrate a vanadium dioxide integrated photonic metamaterial as a transformative platform for multifunctional control. The proposed hybrid metamaterial integrated with transition materials represents a major step forward by providing a universal approach to creating self-sufficient and highly versatile nanophotonic systems.

  7. A multifunctional rotary photoelectric encoder management system

    NASA Astrophysics Data System (ADS)

    Ye, Zunzhong; Ying, Yibin

    2005-11-01

    The rotary photoelectric encoder can be used in many fields, such as robot research, fruit assembly lines, and so on. If there have many photoelectric encoders in one system, it's difficult to manage them and acquire the right pulse number. So it's important to design a multifunctional management system. It includes a powerful microchip with high processing speed, assuring the acquisition precision of rotary pulse. It uses a special method to judge the rotary direction and will be competent for many occasions which rotary direction changes quickly. Considering encoder data transmission, the management system provides a serial port using RS-485 protocol to transmit current pulse data and rotary direction. It allows linking a maximum of 100 management systems using only two communication lines to up-systems and also configing the encoder counting pattern locally (using the keyboard) or remotely (through the computer).

  8. Nanoporous alumina as templates for multifunctional applications

    NASA Astrophysics Data System (ADS)

    Sousa, C. T.; Leitao, D. C.; Proenca, M. P.; Ventura, J.; Pereira, A. M.; Araujo, J. P.

    2014-09-01

    Due to its manufacturing and size tailoring ease, porous anodic alumina (PAA) templates are an elegant physical-chemical nanopatterning approach and an emergent alternative to more sophisticated and expensive methods currently used in nanofabrication. In this review, we will describe the ground work on the fabrication methods of PAA membranes and PAA-based nanostructures. We will present the specificities of the electrochemical growth processes of multifunctional nanomaterials with diversified shapes (e.g., nanowires and nanotubes), and the fabrication techniques used to grow ordered nanohole arrays. We will then focus on the fabrication, properties and applications of magnetic nanostructures grown on PAA and illustrate their dependence on internal (diameter, interpore distance, length, composition) and external (temperature and applied magnetic field intensity and direction) parameters. Finally, the most outstanding experimental findings on PAA-grown nanostructures and their trends for technological applications (sensors, energy harvesting, metamaterials, and biotechnology) will be addressed.

  9. Artificial neural network for multifunctional areas.

    PubMed

    Riccioli, Francesco; El Asmar, Toufic; El Asmar, Jean-Pierre; Fagarazzi, Claudio; Casini, Leonardo

    2016-01-01

    The issues related to the appropriate planning of the territory are particularly pronounced in highly inhabited areas (urban areas), where in addition to protecting the environment, it is important to consider an anthropogenic (urban) development placed in the context of sustainable growth. This work aims at mathematically simulating the changes in the land use, by implementing an artificial neural network (ANN) model. More specifically, it will analyze how the increase of urban areas will develop and whether this development would impact on areas with particular socioeconomic and environmental value, defined as multifunctional areas. The simulation is applied to the Chianti Area, located in the province of Florence, in Italy. Chianti is an area with a unique landscape, and its territorial planning requires a careful examination of the territory in which it is inserted.

  10. Projections from the central amygdaloid nucleus to the precuneiform nucleus in the mouse.

    PubMed

    Liang, Huazheng; Watson, Charles; Paxinos, George

    2015-01-01

    The mouse precuneiform nucleus has been proposed as the midbrain locomotion center, a function ascribed to its caudal neighbor, cuneiform nucleus, in the rat, cat and other species. The present study investigated the projections from the central amygdaloid nucleus to the precuneiform nucleus in the mouse using retrograde tracer injections (fluoro-gold) into the precuneiform nucleus and anterograde tracer injections (biotinylated dextran amine) into the central amygdaloid nucleus. The entire central amygdaloid nucleus except the rostral pole had retrogradely labeled neurons, especially in the middle portion where labeled neurons were densely packed. Anterogradely labeled amygdaloid fibers approached the precuneiform nucleus from the area ventrolateral to it and terminated in the entire precuneiform nucleus. Labeled fibers were also found in laminae 5 and 6 in the upper cervical cord on the ipsilateral side. The present study is the first demonstration of projections from the central amygdaloid nucleus to the precuneiform nucleus. This projection may underpin the role of the precuneiform nucleus in the modulation of the cardiovascular activity.

  11. MULTIFUNCTIONAL SOLAR ENERGY SYSTEMS RESEARCH PROJECT

    SciTech Connect

    Byard Wood, Lance Seefeldt, Ronald Sims, Bradley Wahlen, and Dan Dye

    2012-06-29

    The solar energy available within the visible portion of the solar spectrum is about 300 W/m2 (43%) and that available in the UV and IR portion is about 400 W/m2 (57%). This provides opportunities for developing integrated energy systems that capture and use specific wavelengths of the solar spectrum for different purposes. For example: biofuels from photosynthetic microbes use only the visible light; solar cells use a narrow band of the solar spectrum that could be either mostly in the visible or in the IR regions of the solar spectrum, depending on the photovoltaic materials, e.g., gallium antimonide (GaSb) cells utilize predominately IR radiation; and finally, solar panels that heat water utilize a broad range of wavelengths (visible plus IR). The basic idea of this research is that sunlight has many possible end-use applications including both direct use and energy conversion schemes; it is technically feasible to develop multifunctional solar energy systems capable of addressing several end-use needs while increasing the overall solar energy utilization efficiency when compared to single-purpose solar technologies. Such a combination of technologies could lead to more cost-competitive ?multifunctional? systems that add value and broaden opportunities for integrated energy systems. The goal of this research is to increase the overall energy efficacy and cost competitiveness of solar systems. The specific objectives of this research were: 1) Evaluate the efficacy of a combined photobioreactor and electric power system; 2) Improve the reliability and cost effectiveness of hybrid solar lighting systems ? a technology in which sunlight is collected and distributed via optical fibers into the interior of a building; 3) Evaluate the efficacy of using filtered light to increase the production of biomass in photobioreactors and provide more solar energy for other uses; 4) Evaluates several concepts for wavelength shifting such that a greater percentage of the solar

  12. Advanced Multifunctional MMOD Shield: Radiation Shielding Assessment

    NASA Technical Reports Server (NTRS)

    Rojdev, Kristina; Christiansen, Eric

    2011-01-01

    As NASA is looking to explore further into deep space, multifunctional materials are a necessity for decreasing complexity and mass. One area where multifunctional materials could be extremely beneficial is in the micrometeoroid orbital debris (MMOD) shield. A typical MMOD shield on the International Space Station (ISS) is a stuffed whipple shield consisting of multiple layers. One of those layers is the thermal blanket, or multi-layer insulation (MLI). By increasing the MMOD effectiveness of MLI blankets, while still preserving their thermal capabilities, could allow for a less massive MMOD shield. Thus, a study was conducted to evaluate concept MLI blankets for MMOD shields. In conjunction, these MLI blankets and the subsequent MMOD shields were also evaluated for their radiation shielding effectiveness towards protecting crew. These concepts were evaluated against the ISS MLI blankets and the ISS MMOD shield, which acted as the baseline. These radiation shielding assessments were performed using the high charge and energy transport software (HZETRN). This software is based on a one-dimensional formula of the Boltzmann transport equation with a straight-ahead approximation. Each configuration was evaluated against the following environments to provide a diverse view of radiation shielding effectiveness in most space environments within the heliosphere: August 1972 solar particle event, October 1989 solar particle event, 1982 galactic cosmic ray environment (during solar maximum), 1987 galactic cosmic ray environment (during solar minimum), and a low earth orbit environment in 1970 that corresponded to an altitude of 400 km and inclination of 51.6 . Both the absorbed dose and the dose equivalent were analyzed, but the focus of the discussion was on the dose equivalent since the data is most concerned with radiation shielding of the crew. The following paper outlines the evaluations performed and discusses the results and conclusions of this evaluation for

  13. Managing adaptively for multifunctionality in agricultural systems.

    PubMed

    Hodbod, Jennifer; Barreteau, Olivier; Allen, Craig; Magda, Danièle

    2016-12-01

    The critical importance of agricultural systems for food security and as a dominant global landcover requires management that considers the full dimensions of system functions at appropriate scales, i.e. multifunctionality. We propose that adaptive management is the most suitable management approach for such goals, given its ability to reduce uncertainty over time and support multiple objectives within a system, for multiple actors. As such, adaptive management may be the most appropriate method for sustainably intensifying production whilst increasing the quantity and quality of ecosystem services. However, the current assessment of performance of agricultural systems doesn't reward ecosystem service provision. Therefore, we present an overview of the ecosystem functions agricultural systems should and could provide, coupled with a revised definition for assessing the performance of agricultural systems from a multifunctional perspective that, when all satisfied, would create adaptive agricultural systems that can increase production whilst ensuring food security and the quantity and quality of ecosystem services. The outcome of this high level of performance is the capacity to respond to multiple shocks without collapse, equity and triple bottom line sustainability. Through the assessment of case studies, we find that alternatives to industrialized agricultural systems incorporate more functional goals, but that there are mixed findings as to whether these goals translate into positive measurable outcomes. We suggest that an adaptive management perspective would support the implementation of a systematic analysis of the social, ecological and economic trade-offs occurring within such systems, particularly between ecosystem services and functions, in order to provide suitable and comparable assessments. We also identify indicators to monitor performance at multiple scales in agricultural systems which can be used within an adaptive management framework to increase

  14. Actomyosin contractility rotates the cell nucleus.

    PubMed

    Kumar, Abhishek; Maitra, Ananyo; Sumit, Madhuresh; Ramaswamy, Sriram; Shivashankar, G V

    2014-01-21

    The cell nucleus functions amidst active cytoskeletal filaments, but its response to their contractile stresses is largely unexplored. We study the dynamics of the nuclei of single fibroblasts, with cell migration suppressed by plating onto micro-fabricated patterns. We find the nucleus undergoes noisy but coherent rotational motion. We account for this observation through a hydrodynamic approach, treating the nucleus as a highly viscous inclusion residing in a less viscous fluid of orientable filaments endowed with active stresses. Lowering actin contractility selectively by introducing blebbistatin at low concentrations drastically reduced the speed and coherence of the angular motion of the nucleus. Time-lapse imaging of actin revealed a correlated hydrodynamic flow around the nucleus, with profile and magnitude consistent with the results of our theoretical approach. Coherent intracellular flows and consequent nuclear rotation thus appear to be an intrinsic property of cells.

  15. PERMEATION OF MULTIFUNCTIONAL ACRYLATES THROUGH SELECTED PROTECTIVE GLOVE MATERIALS

    EPA Science Inventory

    In support of the Premanufacture Notification (PMN) program of the Environmental Protection Agency's Office of Toxic Substances, the resistance of three glove materials to permeation by multifunctional acrylate compounds was evaluated through a program for the Office of Research ...

  16. Ferrite Materials for Advanced Multifunction Microwave Systems Applications

    DTIC Science & Technology

    2006-07-05

    TITLE AND SUBTITLE 5. FUNDING NUMBERS Ferrite Materials for Advanced Multifunction Microwave Systems Applications Award No. (Grant) N00014-03-1-0070 PR...were also used in this work. (200 words) 14. SUBJECT TERMS 15. NUMBER OF PAGES Microwave ferrites , yttrium iron garnet, lithium ferrites , hexagonal...Unlimited COVER PAGE FINAL REPORT to the UNITED STATES OFFICE OF NAVAL RESEARCH Ferrite Materials for Advanced Multifunction Microwave Systems

  17. A review of multifunctional structure technology for aerospace applications

    NASA Astrophysics Data System (ADS)

    Sairajan, K. K.; Aglietti, G. S.; Mani, K. M.

    2016-03-01

    The emerging field of multifunctional structure (MFS) technologies enables the design of systems with reduced mass and volume, thereby improving their overall efficiency. It requires developments in different engineering disciplines and their integration into a single system without degrading their individual performances. MFS is particularly suitable for aerospace applications where mass and volume are critical to the cost of the mission. This article reviews the current state of the art of multifunctional structure technologies relevant to aerospace applications.

  18. Multisensory Integration of Visual and Vestibular Signals Improves Heading Discrimination in the Presence of a Moving Object

    PubMed Central

    Dokka, Kalpana; DeAngelis, Gregory C.

    2015-01-01

    Humans and animals are fairly accurate in judging their direction of self-motion (i.e., heading) from optic flow when moving through a stationary environment. However, an object moving independently in the world alters the optic flow field and may bias heading perception if the visual system cannot dissociate object motion from self-motion. We investigated whether adding vestibular self-motion signals to optic flow enhances the accuracy of heading judgments in the presence of a moving object. Macaque monkeys were trained to report their heading (leftward or rightward relative to straight-forward) when self-motion was specified by vestibular, visual, or combined visual-vestibular signals, while viewing a display in which an object moved independently in the (virtual) world. The moving object induced significant biases in perceived heading when self-motion was signaled by either visual or vestibular cues alone. However, this bias was greatly reduced when visual and vestibular cues together signaled self-motion. In addition, multisensory heading discrimination thresholds measured in the presence of a moving object were largely consistent with the predictions of an optimal cue integration strategy. These findings demonstrate that multisensory cues facilitate the perceptual dissociation of self-motion and object motion, consistent with computational work that suggests that an appropriate decoding of multisensory visual-vestibular neurons can estimate heading while discounting the effects of object motion. SIGNIFICANCE STATEMENT Objects that move independently in the world alter the optic flow field and can induce errors in perceiving the direction of self-motion (heading). We show that adding vestibular (inertial) self-motion signals to optic flow almost completely eliminates the errors in perceived heading induced by an independently moving object. Furthermore, this increased accuracy occurs without a substantial loss in the precision. Our results thus demonstrate that

  19. Comparative review of multifunctionality and ecosystem services in sustainable agriculture.

    PubMed

    Huang, Jiao; Tichit, Muriel; Poulot, Monique; Darly, Ségolène; Li, Shuangcheng; Petit, Caroline; Aubry, Christine

    2015-02-01

    Two scientific communities with broad interest in sustainable agriculture independently focus on multifunctional agriculture or ecosystem services. These communities have limited interaction and exchange, and each group faces research challenges according to independently operating paradigms. This paper presents a comparative review of published research in multifunctional agriculture and ecosystem services. The motivation for this work is to improve communication, integrate experimental approaches, and propose areas of consensus and dialog for the two communities. This extensive analysis of publication trends, ideologies, and approaches enables formulation of four main conclusions. First, the two communities are closely related through their use of the term "function." However, multifunctional agriculture considers functions as agricultural activity outputs and prefers farm-centred approaches, whereas ecosystem services considers ecosystem functions in the provision of services and prefers service-centred approaches. Second, research approaches to common questions in these two communities share some similarities, and there would be great value in integrating these approaches. Third, the two communities have potential for dialog regarding the bundle of ecosystem services and the spectrum of multifunctional agriculture, or regarding land sharing and land sparing. Fourth, we propose an integrated conceptual framework that distinguishes six groups of ecosystem services and disservices in the agricultural landscape, and combines the concepts of multifunctional agriculture and ecosystem services. This integrated framework improves applications of multifunctional agriculture and ecosystem services for operational use. Future research should examine if the framework can be readily adapted for modelling specific problems in agricultural management.

  20. Music and the nucleus accumbens.

    PubMed

    Mavridis, Ioannis N

    2015-03-01

    Music is a universal feature of human societies over time, mainly because it allows expression and regulation of strong emotions, thus influencing moods and evoking pleasure. The nucleus accumbens (NA), the most important pleasure center of the human brain (dominates the reward system), is the 'king of neurosciences' and dopamine (DA) can be rightfully considered as its 'crown' due to the fundamental role that this neurotransmitter plays in the brain's reward system. Purpose of this article was to review the existing literature regarding the relation between music and the NA. Studies have shown that reward value for music can be coded by activity levels in the NA, whose functional connectivity with auditory and frontal areas increases as a function of increasing musical reward. Listening to music strongly modulates activity in a network of mesolimbic structures involved in reward processing including the NA. The functional connectivity between brain regions mediating reward, autonomic and cognitive processing provides insight into understanding why listening to music is one of the most rewarding and pleasurable human experiences. Musical stimuli can significantly increase extracellular DA levels in the NA. NA DA and serotonin were found significantly higher in animals exposed to music. Finally, passive listening to unfamiliar although liked music showed activations in the NA.