WorldWideScience

Sample records for vocal communication signals

  1. Auditory Signal Processing in Communication: Perception and Performance of Vocal Sounds

    Science.gov (United States)

    Prather, Jonathan F.

    2013-01-01

    Learning and maintaining the sounds we use in vocal communication require accurate perception of the sounds we hear performed by others and feedback-dependent imitation of those sounds to produce our own vocalizations. Understanding how the central nervous system integrates auditory and vocal-motor information to enable communication is a fundamental goal of systems neuroscience, and insights into the mechanisms of those processes will profoundly enhance clinical therapies for communication disorders. Gaining the high-resolution insight necessary to define the circuits and cellular mechanisms underlying human vocal communication is presently impractical. Songbirds are the best animal model of human speech, and this review highlights recent insights into the neural basis of auditory perception and feedback-dependent imitation in those animals. Neural correlates of song perception are present in auditory areas, and those correlates are preserved in the auditory responses of downstream neurons that are also active when the bird sings. Initial tests indicate that singing-related activity in those downstream neurons is associated with vocal-motor performance as opposed to the bird simply hearing itself sing. Therefore, action potentials related to auditory perception and action potentials related to vocal performance are co-localized in individual neurons. Conceptual models of song learning involve comparison of vocal commands and the associated auditory feedback to compute an error signal that is used to guide refinement of subsequent song performances, yet the sites of that comparison remain unknown. Convergence of sensory and motor activity onto individual neurons points to a possible mechanism through which auditory and vocal-motor signals may be linked to enable learning and maintenance of the sounds used in vocal communication. PMID:23827717

  2. Vocal learning of a communicative signal in captive chimpanzees, Pan troglodytes.

    Science.gov (United States)

    Russell, Jamie L; McIntyre, Joseph M; Hopkins, William D; Taglialatela, Jared P

    2013-12-01

    We hypothesized that chimpanzees could learn to produce attention-getting (AG) sounds via positive reinforcement. We conducted a vocal assessment in 76 captive chimpanzees for their use of AG sounds to acquire the attention of an otherwise inattentive human. Fourteen individuals that did not produce AG sounds during the vocal assessment were evaluated for their ability to acquire the use of an AG sound through operant conditioning and to employ these sounds in an attention-getting context. Nine of the 14 chimpanzees were successfully shaped using positive reinforcement to produce an AG sound. In a post-training vocal assessment, eight of the nine individuals that were successfully trained to produce AG sounds generalized the use of these newly acquired signals to communicatively relevant situations. Chimpanzees possess the ability to acquire the use of a communicative signal via operant conditioning and can generalize the use of this newly acquired signal to appropriate communicative contexts.

  3. Cetacean vocal learning and communication.

    Science.gov (United States)

    Janik, Vincent M

    2014-10-01

    The cetaceans are one of the few mammalian clades capable of vocal production learning. Evidence for this comes from synchronous changes in song patterns of baleen whales and experimental work on toothed whales in captivity. While baleen whales like many vocal learners use this skill in song displays that are involved in sexual selection, toothed whales use learned signals in individual recognition and the negotiation of social relationships. Experimental studies demonstrated that dolphins can use learned signals referentially. Studies on wild dolphins demonstrated how this skill appears to be useful in their own communication system, making them an interesting subject for comparative communication studies.

  4. Universal vocal signals of emotion

    OpenAIRE

    Sauter, D.; Eisner, F.; Ekman, P.; Scott, S.

    2009-01-01

    Emotional signals allow for the sharing of important information with conspecifics, for example to warn them of danger. Humans use a range of different cues to communicate to others how they feel, including facial, vocal, and gestural signals. Although much is known about facial expressions of emotion, less research has focused on affect in the voice. We compare British listeners to individuals from remote Namibian villages who have had no exposure to Western culture, and examine recognition ...

  5. The anuran vocal sac: a tool for multimodal signalling

    OpenAIRE

    STARNBERGER, IRIS; Preininger, Doris; Hödl, Walter

    2014-01-01

    Although in anurans the predominant mode of intra- and intersexual communication is vocalization, modalities used in addition to or instead of acoustic signals range from seismic and visual to chemical. In some cases, signals of more than one modality are produced through or by the anuran vocal sac. However, its role beyond acoustics has been neglected for some time and nonacoustic cues such as vocal sac movement have traditionally been seen as an epiphenomenon of sound production. The divers...

  6. Recording Mouse Ultrasonic Vocalizations to Evaluate Social Communication.

    Science.gov (United States)

    Ferhat, Allain-Thibeault; Torquet, Nicolas; Le Sourd, Anne-Marie; de Chaumont, Fabrice; Olivo-Marin, Jean-Christophe; Faure, Philippe; Bourgeron, Thomas; Ey, Elodie

    2016-06-05

    Mice emit ultrasonic vocalizations in different contexts throughout development and in adulthood. These vocal signals are now currently used as proxies for modeling the genetic bases of vocal communication deficits. Characterizing the vocal behavior of mouse models carrying mutations in genes associated with neuropsychiatric disorders such as autism spectrum disorders will help to understand the mechanisms leading to social communication deficits. We provide here protocols to reliably elicit ultrasonic vocalizations in pups and in adult mice. This standardization will help reduce inter-study variability due to the experimental settings. Pup isolation calls are recorded throughout development from individual pups isolated from dam and littermates. In adulthood, vocalizations are recorded during same-sex interactions (without a sexual component) by exposing socially motivated males or females to an unknown same-sex conspecific. We also provide a protocol to record vocalizations from adult males exposed to an estrus female. In this context, there is a sexual component in the interaction. These protocols are established to elicit a large amount of ultrasonic vocalizations in laboratory mice. However, we point out the important inter-individual variability in the vocal behavior of mice, which should be taken into account by recording a minimal number of individuals (at least 12 in each condition). These recordings of ultrasonic vocalizations are used to evaluate the call rate, the vocal repertoire and the acoustic structure of the calls. Data are combined with the analysis of synchronous video recordings to provide a more complete view on social communication in mice. These protocols are used to characterize the vocal communication deficits in mice lacking ProSAP1/Shank2, a gene associated with autism spectrum disorders. More ultrasonic vocalizations recordings can also be found on the mouseTube database, developed to favor the exchange of such data.

  7. Acoustic communication in the Greater Sage-Grouse (Centrocercus urophasianus) an examination into vocal sacs, sound propagation, and signal directionality

    Science.gov (United States)

    Dantzker, Marc Steven

    The thesis is an inquiry into the acoustic communication of a very unusual avian species, the Greater Sage-Grouse, Centrocercus urophasianus. One of the most outstanding features of this animal's dynamic mating display is its use of paired air sacs that emerge explosively from an esophageal pouch. My first line of inquiry into this system is a review of the form and function of similar vocal apparatuses, collectively called vocal sacs, in birds. Next, with a combination of mathematical models and field measurements, My collaborator and I investigate the acoustic environment where the Greater Sage-Grouse display. The complexities of this acoustic environment are relevant both to the birds and to the subsequent examinations of the display's properties. Finally, my collaborators and I examine a cryptic component of the acoustic display --- directionality --- which we measured simultaneously from multiple locations around free moving grouse on their mating grounds.

  8. HDAC3 Inhibitor RGFP966 Modulates Neuronal Memory for Vocal Communication Signals in a Songbird Model

    Directory of Open Access Journals (Sweden)

    Mimi L. Phan

    2017-09-01

    plasticity underlying the formation of specific memories for conspecific communication sounds. This is the first evidence in zebra finches that epigenetic mechanisms may contribute to gene expression events for memory of acoustically-rich sensory cues.

  9. The anuran vocal sac: a tool for multimodal signalling

    Science.gov (United States)

    Starnberger, Iris; Preininger, Doris; Hödl, Walter

    2014-01-01

    Although in anurans the predominant mode of intra- and intersexual communication is vocalization, modalities used in addition to or instead of acoustic signals range from seismic and visual to chemical. In some cases, signals of more than one modality are produced through or by the anuran vocal sac. However, its role beyond acoustics has been neglected for some time and nonacoustic cues such as vocal sac movement have traditionally been seen as an epiphenomenon of sound production. The diversity in vocal sac coloration and shape found in different species is striking and recently its visual properties have been given a more important role in signalling. Chemosignals seem to be the dominant communication mode in newts, salamanders and caecilians and certainly play a role in the aquatic life phase of anurans, but airborne chemical signalling has received less attention. There is, however, increasing evidence that at least some terrestrial anuran species integrate acoustic, visual and chemical cues in species recognition and mate choice and a few secondarily mute anuran species seem to fully rely on volatile chemical cues produced in glands on the vocal sac. Within vertebrates, frogs in particular are suitable organisms for investigating multimodal communication by means of experiments, since they are tolerant of disturbance by observers and can be easily manipulated under natural conditions. Thus, the anuran vocal sac might be of great interest not only to herpetologists, but also to behavioural biologists studying communication systems. PMID:25389375

  10. Vocal communication in African elephants (Loxodonta africana).

    Science.gov (United States)

    Soltis, Joseph

    2010-01-01

    Research on vocal communication in African elephants has increased in recent years, both in the wild and in captivity, providing an opportunity to present a comprehensive review of research related to their vocal behavior. Current data indicate that the vocal repertoire consists of perhaps nine acoustically distinct call types, "rumbles" being the most common and acoustically variable. Large vocal production anatomy is responsible for the low-frequency nature of rumbles, with fundamental frequencies in the infrasonic range. Additionally, resonant frequencies of rumbles implicate the trunk in addition to the oral cavity in shaping the acoustic structure of rumbles. Long-distance communication is thought possible because low-frequency sounds propagate more faithfully than high-frequency sounds, and elephants respond to rumbles at distances of up to 2.5 km. Elephant ear anatomy appears designed for detecting low frequencies, and experiments demonstrate that elephants can detect infrasonic tones and discriminate small frequency differences. Two vocal communication functions in the African elephant now have reasonable empirical support. First, closely bonded but spatially separated females engage in rumble exchanges, or "contact calls," that function to coordinate movement or reunite animals. Second, both males and females produce "mate attraction" rumbles that may advertise reproductive states to the opposite sex. Additionally, there is evidence that the structural variation in rumbles reflects the individual identity, reproductive state, and emotional state of callers. Growth in knowledge about the communication system of the African elephant has occurred from a rich combination of research on wild elephants in national parks and captive elephants in zoological parks.

  11. Path Models of Vocal Emotion Communication.

    Directory of Open Access Journals (Sweden)

    Tanja Bänziger

    Full Text Available We propose to use a comprehensive path model of vocal emotion communication, encompassing encoding, transmission, and decoding processes, to empirically model data sets on emotion expression and recognition. The utility of the approach is demonstrated for two data sets from two different cultures and languages, based on corpora of vocal emotion enactment by professional actors and emotion inference by naïve listeners. Lens model equations, hierarchical regression, and multivariate path analysis are used to compare the relative contributions of objectively measured acoustic cues in the enacted expressions and subjective voice cues as perceived by listeners to the variance in emotion inference from vocal expressions for four emotion families (fear, anger, happiness, and sadness. While the results confirm the central role of arousal in vocal emotion communication, the utility of applying an extended path modeling framework is demonstrated by the identification of unique combinations of distal cues and proximal percepts carrying information about specific emotion families, independent of arousal. The statistical models generated show that more sophisticated acoustic parameters need to be developed to explain the distal underpinnings of subjective voice quality percepts that account for much of the variance in emotion inference, in particular voice instability and roughness. The general approach advocated here, as well as the specific results, open up new research strategies for work in psychology (specifically emotion and social perception research and engineering and computer science (specifically research and development in the domain of affective computing, particularly on automatic emotion detection and synthetic emotion expression in avatars.

  12. Path Models of Vocal Emotion Communication.

    Science.gov (United States)

    Bänziger, Tanja; Hosoya, Georg; Scherer, Klaus R

    2015-01-01

    We propose to use a comprehensive path model of vocal emotion communication, encompassing encoding, transmission, and decoding processes, to empirically model data sets on emotion expression and recognition. The utility of the approach is demonstrated for two data sets from two different cultures and languages, based on corpora of vocal emotion enactment by professional actors and emotion inference by naïve listeners. Lens model equations, hierarchical regression, and multivariate path analysis are used to compare the relative contributions of objectively measured acoustic cues in the enacted expressions and subjective voice cues as perceived by listeners to the variance in emotion inference from vocal expressions for four emotion families (fear, anger, happiness, and sadness). While the results confirm the central role of arousal in vocal emotion communication, the utility of applying an extended path modeling framework is demonstrated by the identification of unique combinations of distal cues and proximal percepts carrying information about specific emotion families, independent of arousal. The statistical models generated show that more sophisticated acoustic parameters need to be developed to explain the distal underpinnings of subjective voice quality percepts that account for much of the variance in emotion inference, in particular voice instability and roughness. The general approach advocated here, as well as the specific results, open up new research strategies for work in psychology (specifically emotion and social perception research) and engineering and computer science (specifically research and development in the domain of affective computing, particularly on automatic emotion detection and synthetic emotion expression in avatars).

  13. Wild chimpanzees' use of single and combined vocal and gestural signals.

    Science.gov (United States)

    Hobaiter, C; Byrne, R W; Zuberbühler, K

    2017-01-01

    We describe the individual and combined use of vocalizations and gestures in wild chimpanzees. The rate of gesturing peaked in infancy and, with the exception of the alpha male, decreased again in older age groups, while vocal signals showed the opposite pattern. Although gesture-vocal combinations were relatively rare, they were consistently found in all age groups, especially during affiliative and agonistic interactions. Within behavioural contexts rank (excluding alpha-rank) had no effect on the rate of male chimpanzees' use of vocal or gestural signals and only a small effect on their use of combination signals. The alpha male was an outlier, however, both as a prolific user of gestures and recipient of high levels of vocal and gesture-vocal signals. Persistence in signal use varied with signal type: chimpanzees persisted in use of gestures and gesture-vocal combinations after failure, but where their vocal signals failed they tended to add gestural signals to produce gesture-vocal combinations. Overall, chimpanzees employed signals with a sensitivity to the public/private nature of information, by adjusting their use of signal types according to social context and by taking into account potential out-of-sight audiences. We discuss these findings in relation to the various socio-ecological challenges that chimpanzees are exposed to in their natural forest habitats and the current discussion of multimodal communication in great apes. All animal communication combines different types of signals, including vocalizations, facial expressions, and gestures. However, the study of primate communication has typically focused on the use of signal types in isolation. As a result, we know little on how primates use the full repertoire of signals available to them. Here we present a systematic study on the individual and combined use of gestures and vocalizations in wild chimpanzees. We find that gesturing peaks in infancy and decreases in older age, while vocal signals

  14. When internal communication becomes multi-vocal

    DEFF Research Database (Denmark)

    Madsen, Vibeke Thøis

    The aim of this paper is to present the findings of an exploratory case study of communication on internal social media within the Danish bank, Jyske Bank. The study involved an analysis of staff interaction on internal social media over three months, as well as interviews with 17 of the bank’s...... employees. The study not only answers questions about who participates in internal social media and the content of their communication, it also shows that when organizational culture and management support coworker communication, internal social media becomes a multi-vocal rhetorical arena where coworkers...... are likely to converse about how to solve product and customer-related challenges, and to discuss working conditions. In addition, this study shows that coworkers co-construct organizational identity when they discuss questions such as: Who are we as an organization? Which products should we provide...

  15. Monkey drumming reveals common networks for perceiving vocal and nonvocal communication sounds.

    Science.gov (United States)

    Remedios, Ryan; Logothetis, Nikos K; Kayser, Christoph

    2009-10-20

    Salient sounds such as those created by drumming can serve as means of nonvocal acoustic communication in addition to vocal sounds. Despite the ubiquity of drumming across human cultures, its origins and the brain regions specialized in processing such signals remain unexplored. Here, we report that an important animal model for vocal communication, the macaque monkey, also displays drumming behavior, and we exploit this finding to show that vocal and nonvocal communication sounds are represented by overlapping networks in the brain's temporal lobe. Observing social macaque groups, we found that these animals use artificial objects to produce salient periodic sounds, similar to acoustic gestures. Behavioral tests confirmed that these drumming sounds attract the attention of listening monkeys similarly as conspecific vocalizations. Furthermore, in a preferential looking experiment, drumming sounds influenced the way monkeys viewed their conspecifics, suggesting that drumming serves as a multimodal signal of social dominance. Finally, by using high-resolution functional imaging we identified those brain regions preferentially activated by drumming sounds or by vocalizations and found that the representations of both these communication sounds overlap in caudal auditory cortex and the amygdala. The similar behavioral responses to drumming and vocal sounds, and their shared neural representation, suggest a common origin of primate vocal and nonvocal communication systems and support the notion of a gestural origin of speech and music.

  16. Meaning, intention, and inference in primate vocal communication.

    Science.gov (United States)

    Fischer, Julia; Price, Tabitha

    2016-10-20

    Two core questions in the study of speech evolution are whether nonhuman primate signals should be conceived as referential, and what the role of social cognition is in primate communication. Current evidence suggests that the structure of primate vocalizations is largely innate and related to the affective/motivational state of the caller, with a probabilistic and underdetermined relationship between specific events and calls. Moreover, nonhuman primates do not appear to express or comprehend communicative or informative intent, which is in line with a lack of mental state attribution to others. We argue that nonhuman primate vocalizations as well as gestures should be best conceived as goal-directed, where signallers are sensitive to the relation between their signalling and receivers' responses. Receivers in turn use signals to predict signaller behaviour. In combination with their ability to integrate information from multiple sources, this renders the system as a whole relatively powerful, despite the lack of higher-order intentionality on the side of sender or receiver. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. Molecular mapping of brain areas involved in parrot vocal communication.

    Science.gov (United States)

    Jarvis, E D; Mello, C V

    2000-03-27

    Auditory and vocal regulation of gene expression occurs in separate discrete regions of the songbird brain. Here we demonstrate that regulated gene expression also occurs during vocal communication in a parrot, belonging to an order whose ability to learn vocalizations is thought to have evolved independently of songbirds. Adult male budgerigars (Melopsittacus undulatus) were stimulated to vocalize with playbacks of conspecific vocalizations (warbles), and their brains were analyzed for expression of the transcriptional regulator ZENK. The results showed that there was distinct separation of brain areas that had hearing- or vocalizing-induced ZENK expression. Hearing warbles resulted in ZENK induction in large parts of the caudal medial forebrain and in 1 midbrain region, with a pattern highly reminiscent of that observed in songbirds. Vocalizing resulted in ZENK induction in nine brain structures, seven restricted to the lateral and anterior telencephalon, one in the thalamus, and one in the midbrain, with a pattern partially reminiscent of that observed in songbirds. Five of the telencephalic structures had been previously described as part of the budgerigar vocal control pathway. However, functional boundaries defined by the gene expression patterns for some of these structures were much larger and different in shape than previously reported anatomical boundaries. Our results provide the first functional demonstration of brain areas involved in vocalizing and auditory processing of conspecific sounds in budgerigars. They also indicate that, whether or not vocal learning evolved independently, some of the gene regulatory mechanisms that accompany learned vocal communication are similar in songbirds and parrots.

  18. Vocal Nonverbal Communication Skill and Deliberate Social Influence.

    Science.gov (United States)

    Hall, Judith A.

    An experiment tested the hypothesis that the outcome of a vocal nonverbal persuasion attempt can be affected by the participants' skills in nonverbal communication. Subjects' vocal sending or decoding abilities were pretested. Senders and decoders (N=54) were agents and recipients of social influence, respectively, in a field experiment in which…

  19. THE EVOKED VOCAL RESPONSE OF THE BULLFROG; A STUDY OF COMMUNICATION BY SOUND.

    Science.gov (United States)

    The research attempts to bridge the existing gap between the naturalistic observations of sound communication in anurans and the anatomical and...principles by which information is processed within the intact animal. To this end, vocal behavior has been evoked from the males of laboratory colonies of...bullfrogs (Rana catesbeiana) in response to a restricted class of natural and synthetic sounds. The evoked vocal responses, having the signal

  20. Vocal communication in a complex multi-level society: constrained acoustic structure and flexible call usage in Guinea baboons

    National Research Council Canada - National Science Library

    Maciej, Peter; Ndao, Ibrahima; Hammerschmidt, Kurt; Fischer, Julia

    2013-01-01

    To understand the evolution of acoustic communication in animals, it is important to distinguish between the structure and the usage of vocal signals, since both aspects are subject to different constraints...

  1. General principles involved in the effect of noise on hearing and vocal communication in birds

    Science.gov (United States)

    Dooling, Robert J.; Dent, Michael L.

    2002-05-01

    Birds provide very useful models for understanding the effects of noise on hearing and acoustic communication. They are excellent subjects for laboratory studies of hearing in which signals and noise can be precisely defined and delivered and behavioral responses can be unambiguously interpreted. For this reason, a huge amount is already known about their hearing. Acoustic communication is critically important for most species of birds and some even acquire their communication signals through vocal learning. For this reason, a lot is already known about how birds perceive complex acoustic signals such as vocalizations. Drawing from both field and laboratory studies, we review what is known about the effects of noise on hearing and vocal communication in birds. This includes the effects of intense noise on the ear, the effects of background noise on the detection and discrimination of both simple sounds and complex vocalizations, and the spatial effects of signal detection in noise in the free-field. As a whole, these studies show that birds are resistant to damage and interference from noise and have developed a variety of strategies to effectively communicate.

  2. Acoustic communication in Panthera tigris: A study of tiger vocalization and auditory receptivity

    Science.gov (United States)

    Walsh, Edward J.; Wang, Lily M.; Armstrong, Douglas L.; Curro, Thomas; Simmons, Lee G.; McGee, Joann

    2003-04-01

    Acoustic communication represents a primary mode of interaction within the sub-species of Panthera tigris and it is commonly known that their vocal repertoire consists of a relatively wide range of utterances that include roars, growls, grunts, hisses and chuffling, vocalizations that are in some cases produced with extraordinary power. P. tigris vocalizations are known to contain significant amounts of acoustic energy over a wide spectral range, with peak output occurring in a low frequency bandwidth in the case of roars. von Muggenthaler (2000) has also shown that roars and other vocal productions uttered by P. tigris contain energy in the infrasonic range. While it is reasonable to assume that low and infrasonic acoustic cues are used as communication signals among conspecifics in the wild, it is clearly necessary to demonstrate that members of the P. tigris sub-species are responsive to low and infrasonic acoustic signals. The auditory brainstem response has proven to be an effective tool in the characterization of auditory performance among tigers and the results of an ongoing study of both the acoustical properties of P. tigris vocalizations and their auditory receptivity support the supposition that tigers are not only responsive to low frequency stimulation, but exquisitely so.

  3. Chimpanzee vocal signaling points to a multimodal origin of human language.

    Directory of Open Access Journals (Sweden)

    Jared P Taglialatela

    Full Text Available The evolutionary origin of human language and its neurobiological foundations has long been the object of intense scientific debate. Although a number of theories have been proposed, one particularly contentious model suggests that human language evolved from a manual gestural communication system in a common ape-human ancestor. Consistent with a gestural origins theory are data indicating that chimpanzees intentionally and referentially communicate via manual gestures, and the production of manual gestures, in conjunction with vocalizations, activates the chimpanzee Broca's area homologue--a region in the human brain that is critical for the planning and execution of language. However, it is not known if this activity observed in the chimpanzee Broca's area is the result of the chimpanzees producing manual communicative gestures, communicative sounds, or both. This information is critical for evaluating the theory that human language evolved from a strictly manual gestural system. To this end, we used positron emission tomography (PET to examine the neural metabolic activity in the chimpanzee brain. We collected PET data in 4 subjects, all of whom produced manual communicative gestures. However, 2 of these subjects also produced so-called attention-getting vocalizations directed towards a human experimenter. Interestingly, only the two subjects that produced these attention-getting sounds showed greater mean metabolic activity in the Broca's area homologue as compared to a baseline scan. The two subjects that did not produce attention-getting sounds did not. These data contradict an exclusive "gestural origins" theory for they suggest that it is vocal signaling that selectively activates the Broca's area homologue in chimpanzees. In other words, the activity observed in the Broca's area homologue reflects the production of vocal signals by the chimpanzees, suggesting that this critical human language region was involved in vocal signaling in

  4. Using naturalistic utterances to investigate vocal communication processing and development in human and non-human primates.

    Science.gov (United States)

    Talkington, William J; Taglialatela, Jared P; Lewis, James W

    2013-11-01

    Humans and several non-human primates possess cortical regions that are most sensitive to vocalizations produced by their own kind (conspecifics). However, the use of speech and other broadly defined categories of behaviorally relevant natural sounds has led to many discrepancies regarding where voice-sensitivity occurs, and more generally the identification of cortical networks, "proto-networks" or protolanguage networks, and pathways that may be sensitive or selective for certain aspects of vocalization processing. In this prospective review we examine different approaches for exploring vocal communication processing, including pathways that may be, or become, specialized for conspecific utterances. In particular, we address the use of naturally produced non-stereotypical vocalizations (mimicry of other animal calls) as another category of vocalization for use with human and non-human primate auditory systems. We focus this review on two main themes, including progress and future ideas for studying vocalization processing in great apes (chimpanzees) and in very early stages of human development, including infants and fetuses. Advancing our understanding of the fundamental principles that govern the evolution and early development of cortical pathways for processing non-verbal communication utterances is expected to lead to better diagnoses and early intervention strategies in children with communication disorders, improve rehabilitation of communication disorders resulting from brain injury, and develop new strategies for intelligent hearing aid and implant design that can better enhance speech signals in noisy environments. This article is part of a Special Issue entitled "Communication Sounds and the Brain: New Directions and Perspectives".

  5. Amplitude Modulations of Acoustic Communication Signals

    Science.gov (United States)

    Turesson, Hjalmar K.

    2011-12-01

    In human speech, amplitude modulations at 3 -- 8 Hz are important for discrimination and detection. Two different neurophysiological theories have been proposed to explain this effect. The first theory proposes that, as a consequence of neocortical synaptic dynamics, signals that are amplitude modulated at 3 -- 8 Hz are propagated better than un-modulated signals, or signals modulated above 8 Hz. This suggests that neural activity elicited by vocalizations modulated at 3 -- 8 Hz is optimally transmitted, and the vocalizations better discriminated and detected. The second theory proposes that 3 -- 8 Hz amplitude modulations interact with spontaneous neocortical oscillations. Specifically, vocalizations modulated at 3 -- 8 Hz entrain local populations of neurons, which in turn, modulate the amplitude of high frequency gamma oscillations. This suggests that vocalizations modulated at 3 -- 8 Hz should induce stronger cross-frequency coupling. Similar to human speech, we found that macaque monkey vocalizations also are amplitude modulated between 3 and 8 Hz. Humans and macaque monkeys share similarities in vocal production, implying that the auditory systems subserving perception of acoustic communication signals also share similarities. Based on the similarities between human speech and macaque monkey vocalizations, we addressed how amplitude modulated vocalizations are processed in the auditory cortex of macaque monkeys, and what behavioral relevance modulations may have. Recording single neuron activity, as well as, the activity of local populations of neurons allowed us to test both of the neurophysiological theories presented above. We found that single neuron responses to vocalizations amplitude modulated at 3 -- 8 Hz resulted in better stimulus discrimination than vocalizations lacking 3 -- 8 Hz modulations, and that the effect most likely was mediated by synaptic dynamics. In contrast, we failed to find support for the oscillation-based model proposing a

  6. Team of rivals: alliance formation in territorial songbirds is predicted by vocal signal structure.

    Science.gov (United States)

    Goodwin, Sarah E; Podos, Jeffrey

    2014-02-01

    Cooperation and conflict are regarded as diametric extremes of animal social behaviour, yet the two may intersect under rare circumstances. We here report that territorial competitors in a common North American songbird species, the chipping sparrow (Spizella passerina), sometimes form temporary coalitions in the presence of simulated territorial intruders. Moreover, analysis of birds' vocal mating signals (songs) reveals that coalitions occur nearly exclusively under specific triadic relationships, in which vocal performances of allies and simulated intruders exceed those of residents. Our results provide the first evidence that animals like chipping sparrows rely on precise assessments of mating signal features, as well as relative comparisons of signal properties among multiple animals in communication networks, when deciding when and with whom to form temporary alliances against a backdrop of competition and rivalry.

  7. Communication Signals in Lizards.

    Science.gov (United States)

    Carpenter, Charles C.

    1983-01-01

    Discusses mechanisms and functional intent of visual communication signals in iguanid/agamid lizards. Demonstrated that lizards communicate with each other by using pushups and head nods and that each species does this in its own way, conveying different types of information. (JN)

  8. Vocalizations of eight species of Atelopus (Anura: Bufonidae) with comments on communication in the genus

    Science.gov (United States)

    Cocroft, R.B.; McDiarmid, R.W.; Jaslow, A.P.; Ruiz-Carranza, P.M.

    1990-01-01

    Vocalizations of frogs of the genus Atelopus include three discrete types of signals: pulsed calls, pure tone calls, and short calls. Repertoire composition is conservative across species. Repertoires of most species whose calls have been recorded contain two or three of these identifiable call types. Within a call type, details of call structure are very similar across species. This apparent lack of divergence in calls may be related to the rarity of sympatry among species of Atelopus and to the relative importance of visual communication in their social interactions.

  9. Effects of familiar contingencies on infants' vocal behavior in new communicative contexts.

    Science.gov (United States)

    Miller, Jennifer L

    2014-11-01

    Recently, there has been a growing interest in understanding the mechanisms underlying vocal learning in songbirds and human infants. Research has demonstrated how contingent social feedback from social partners to immature vocalizations can play a role during vocal learning in both brown-headed cowbirds and prelinguistic infants. Contingencies in social interactions, particularly familiar contingencies, are important in developing preferences for social partners and shaping social exchanges Bigelow and Birch [1999]. Infant Behavior & Development 22:367-382]; however, little is known about how familiar contingencies that individuals experience during communicative exchanges play a role in new contexts. The current study examined differences in caregiver response patterns to infant vocal behavior and assessed how familiar contingencies influenced infant vocal behavior in novel communicative exchanges with caregivers. Infants were systematically exposed to high and low social feedback schedules during a play session. Results revealed the frequency of caregiver responsiveness to which infants were accustomed to affected infant vocal production during novel communicative situations. Infants with high responding caregivers vocalized with more mature vocalizations and used their vocalizations differently than infants with low responding caregivers during the high, but not low, response period. Specifically, infants with high responding caregivers directed more of their vocalizations at their caregiver and looked more at their caregiver after vocalizing, an indication of anticipating contingent responding. These results suggest that infants with high responding caregivers learned the association between vocalizing and contingent responses during the novel communicative interaction. This study demonstrates the need to understand how infants who experience a variety of contingencies in everyday interactions with caregivers carry over to other interactive situations.

  10. Animal Models of Speech and Vocal Communication Deficits Associated With Psychiatric Disorders.

    Science.gov (United States)

    Konopka, Genevieve; Roberts, Todd F

    2016-01-01

    Disruptions in speech, language, and vocal communication are hallmarks of several neuropsychiatric disorders, most notably autism spectrum disorders. Historically, the use of animal models to dissect molecular pathways and connect them to behavioral endophenotypes in cognitive disorders has proven to be an effective approach for developing and testing disease-relevant therapeutics. The unique aspects of human language compared with vocal behaviors in other animals make such an approach potentially more challenging. However, the study of vocal learning in species with analogous brain circuits to humans may provide entry points for understanding this human-specific phenotype and diseases. We review animal models of vocal learning and vocal communication and specifically link phenotypes of psychiatric disorders to relevant model systems. Evolutionary constraints in the organization of neural circuits and synaptic plasticity result in similarities in the brain mechanisms for vocal learning and vocal communication. Comparative approaches and careful consideration of the behavioral limitations among different animal models can provide critical avenues for dissecting the molecular pathways underlying cognitive disorders that disrupt speech, language, and vocal communication. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  11. Primate vocal communication: a useful tool for understanding human speech and language evolution?

    Science.gov (United States)

    Fedurek, Pawel; Slocombe, Katie E

    2011-04-01

    Language is a uniquely human trait, and questions of how and why it evolved have been intriguing scientists for years. Nonhuman primates (primates) are our closest living relatives, and their behavior can be used to estimate the capacities of our extinct ancestors. As humans and many primate species rely on vocalizations as their primary mode of communication, the vocal behavior of primates has been an obvious target for studies investigating the evolutionary roots of human speech and language. By studying the similarities and differences between human and primate vocalizations, comparative research has the potential to clarify the evolutionary processes that shaped human speech and language. This review examines some of the seminal and recent studies that contribute to our knowledge regarding the link between primate calls and human language and speech. We focus on three main aspects of primate vocal behavior: functional reference, call combinations, and vocal learning. Studies in these areas indicate that despite important differences, primate vocal communication exhibits some key features characterizing human language. They also indicate, however, that some critical aspects of speech, such as vocal plasticity, are not shared with our primate cousins. We conclude that comparative research on primate vocal behavior is a very promising tool for deepening our understanding of the evolution of human speech and language, but much is still to be done as many aspects of monkey and ape vocalizations remain largely unexplored.

  12. Vocal signals in a tropical avian species, the redvented bulbul Pycnonotus cafer: their characteristics and importance

    Indian Academy of Sciences (India)

    Anil Kumar; Dinesh Bhatt

    2000-12-01

    Acoustic signals play an important role in the lives of birds. Almost all avian species produce vocal signals in a variety of contexts either in the form of calls or songs or both. In the present study different types of vocal signals of the tropical avian species Pycnonotus cafer were characterized on the basis of their physical characteristics and context of production. This species used six types of vocal signals: contact signals, roosting signals, alarm signals, twittering signals, distress signals and begging signals. Two types of alarm signals are produced based on predation pressure. These signals are dissimilar in all physical characteristics except for dominant frequency. Although alarm signal type I and roosting signals are phonetically similar, they have completely different sonogram characteristics.

  13. Predicting the effect of urban noise on the active space of avian vocal signals.

    Science.gov (United States)

    Parris, Kirsten M; McCarthy, Michael A

    2013-10-01

    Urbanization changes the physical environment of nonhuman species but also markedly changes their acoustic environment. Urban noise interferes with acoustic communication in a range of animals, including birds, with potentially profound impacts on fitness. However, a mechanistic theory to predict which species of birds will be most affected by urban noise is lacking. We develop a mathematical model to predict the decrease in the active space of avian vocal signals after moving from quiet forest habitats to noisy urban habitats. We find that the magnitude of the decrease is largely a function of signal frequency. However, this relationship is not monotonic. A metaregression of observed increases in the frequency of birdsong in urban noise supports the model's predictions for signals with frequencies between 1.5 and 4 kHz. Using results of the metaregression and the model described above, we show that the expected gain in active space following observed frequency shifts is up to 12% and greatest for birds with signals at the lower end of this frequency range. Our generally applicable model, along with three predictions regarding the behavioral and population-level responses of birds to urban noise, represents an important step toward a theory of acoustic communication in urban habitats.

  14. Identification of Vocal Communication of Emotions Across Cultures.

    Science.gov (United States)

    Beier, Ernst G.; Zautra, Alexander

    The experiment discussed in this report investigates cross cultural ability to decode emotive meaning in extra-verbal vocal expressions of mood. The principal expectation of the study is that primitive mood expressions are understood in much the same way in all the countries tested. The moods depicted in the study--angry, sad, happy, flirtatious,…

  15. Crisis Communication and the Rhetorical Arena - A Multi-Vocal Approach

    DEFF Research Database (Denmark)

    Johansen, Winni; Frandsen, Finn

    2005-01-01

    Presentation of a new model of crisis communication called the rhetorical arena. This new model is compared to W. Benoit's theory of image restoration strategies and T. Coomb's theory of crisis communication as relationship management. The new model is based on a multi-vocal approach taking...... into account the many corporate and non corporate 'voices' which meet, compete, collaborate or negotiate during a crisis situation. The model conceives crisis communication as mediated through four parameters: context, media, genre, and text....

  16. Sub-vocal speech pattern recognition of Hindi alphabet with surface electromyography signal

    Directory of Open Access Journals (Sweden)

    Munna Khan

    2016-09-01

    Full Text Available Recently electromyography (EMG based speech signals have been used as pattern recognition of phoneme, vocal frequency estimation, browser interface, and classification of speech related problem identification. Attempts have been made to use EMG signal for sub-vocal speech pattern recognition of Hindi phonemes fx1,fx2,fx3,fx4 and Hindi words. That provides the command sub-vocally to control the devices. Sub-vocal EMG data were collected from more than 10 healthy subjects aged between 25 and 30 years. EMG-based sub-vocal database are acquired from four channel BIOPAC MP-30 acquisition system. Four pairs of Ag-AgCl electrodes placed in the participant neck area of skin. AR coefficients and Cepstral coefficients were computed as features of EMG-based sub-vocal signal. Furthermore, these features are classified by HMM classifier. H2M MATLAB toolbox was used to develop HMM classifier for classification of phonemes. Results were averaged on 10 subjects. An average classification accuracy of Ka is found to be 85% whereas the classification accuracy of Kha and Gha is in between 88% and 90%. The classification accuracy rate of Ga was found to be 78% which was lesser as compared to Kha and Gha.

  17. Neural processing of short-term recurrence in songbird vocal communication.

    Directory of Open Access Journals (Sweden)

    Gabriël J L Beckers

    Full Text Available BACKGROUND: Many situations involving animal communication are dominated by recurring, stereotyped signals. How do receivers optimally distinguish between frequently recurring signals and novel ones? Cortical auditory systems are known to be pre-attentively sensitive to short-term delivery statistics of artificial stimuli, but it is unknown if this phenomenon extends to the level of behaviorally relevant delivery patterns, such as those used during communication. METHODOLOGY/PRINCIPAL FINDINGS: We recorded and analyzed complete auditory scenes of spontaneously communicating zebra finch (Taeniopygia guttata pairs over a week-long period, and show that they can produce tens of thousands of short-range contact calls per day. Individual calls recur at time scales (median interval 1.5 s matching those at which mammalian sensory systems are sensitive to recent stimulus history. Next, we presented to anesthetized birds sequences of frequently recurring calls interspersed with rare ones, and recorded, in parallel, action and local field potential responses in the medio-caudal auditory forebrain at 32 unique sites. Variation in call recurrence rate over natural ranges leads to widespread and significant modulation in strength of neural responses. Such modulation is highly call-specific in secondary auditory areas, but not in the main thalamo-recipient, primary auditory area. CONCLUSIONS/SIGNIFICANCE: Our results support the hypothesis that pre-attentive neural sensitivity to short-term stimulus recurrence is involved in the analysis of auditory scenes at the level of delivery patterns of meaningful sounds. This may enable birds to efficiently and automatically distinguish frequently recurring vocalizations from other events in their auditory scene.

  18. High-pitched notes during vocal contests signal genetic diversity in ocellated antbirds.

    Directory of Open Access Journals (Sweden)

    Yi-Men Araya-Ajoy

    Full Text Available Animals use honest signals to assess the quality of competitors during aggressive interactions. Current theory predicts that honest signals should be costly to produce and thus reveal some aspects of the phenotypic or genetic quality of the sender. In songbirds, research indicates that biomechanical constraints make the production of some acoustic features costly. Furthermore, recent studies have found that vocal features are related to genetic diversity. We linked these two lines of research by evaluating if constrained acoustic features reveal male genetic diversity during aggressive interactions in ocellated antbirds (Phaenostictus mcleannani. We recorded the aggressive vocalizations of radiotagged males at La Selva Biological Station in Costa Rica, and found significant variation in the highest frequency produced among individuals. Moreover, we detected a negative relationship between the frequency of the highest pitched note and vocalization duration, suggesting that high pitched notes might constrain the duration of vocalizations through biomechanical and/or energetic limitations. When we experimentally exposed wild radiotagged males to simulated acoustic challenges, the birds increased the pitch of their vocalization. We also found that individuals with higher genetic diversity (as measured by zygosity across 9 microsatellite loci produced notes of higher pitch during aggressive interactions. Overall, our results suggest that the ability to produce high pitched notes is an honest indicator of male genetic diversity in male-male aggressive interactions.

  19. Chaotic signals in digital communications

    CERN Document Server

    Eisencraft, Marcio; Suyama, Ricardo

    2013-01-01

    Chaotic Signals in Digital Communications combines fundamental background knowledge with state-of-the-art methods for using chaotic signals and systems in digital communications. The book builds a bridge between theoretical works and practical implementation to help researchers attain consistent performance in realistic environments. It shows the possible shortcomings of the chaos-based communication systems proposed in the literature, particularly when they are subjected to non-ideal conditions. It also presents a toolbox of techniques for researchers working to actually implement such system

  20. Signals in Communication Engineering History

    Science.gov (United States)

    Consonni, Denise; Silva, Magno T. M.

    2010-01-01

    This paper is a study of various electric signals, which have been employed throughout the history of communication engineering in its two main landmarks: the telegraph and the telephone. The signals are presented in their time and frequency domain representations. The historical order has been followed in the presentation: wired systems, spark…

  1. Signals in Communication Engineering History

    Science.gov (United States)

    Consonni, Denise; Silva, Magno T. M.

    2010-01-01

    This paper is a study of various electric signals, which have been employed throughout the history of communication engineering in its two main landmarks: the telegraph and the telephone. The signals are presented in their time and frequency domain representations. The historical order has been followed in the presentation: wired systems, spark…

  2. Reelin signaling in the basal ganglia: comparative neuroanatomy and implications for vocal behavior

    OpenAIRE

    Fraley, Elizabeth Ross

    2017-01-01

    Vocal learning is a complex motor activity that relies on the coordination of different brain regions including the basal ganglia. By studying the vocal learning zebra finch, this work has uncovered a novel pathway that is regulated by singing behavior. The Reelin-signaling pathway like the human language transcription factor, FoxP2, is regulated in a basal ganglia region, Area X. The pathway was found to be regulated during the sensorimotor phase of song learning in finches as well as in adu...

  3. Relationships between vocalization forms and functions in infancy: preliminary implications for early communicative assessment and intervention.

    Science.gov (United States)

    Iyer, Suneeti Nathani; Ertmer, David J

    2014-11-01

    This preliminary study explored relationships between form and function in prelinguistic vocalizations to increase our understanding of early communicative development and to provide potential clinical implications for early communicative assessment and intervention. Twenty typically developing infants-5 infants in each of 4 age groups, from 3 to 20 months of age-were included. Vocalizations from these infants had previously been categorized for their form (Nathani, Ertmer, & Stark, 2006) and function (Stark, Bernstein, & Demorest, 1993) characteristics. In the present study, cross-classification tabulations between form and function were conducted to examine relationships between vocalization types and their apparent uses. As anticipated, earlier developing forms were mostly associated with earlier developing functions, and later developing forms were mostly associated with later developing functions. However, there were some exceptions such that some forms were associated with a variety of functions, and vice versa. The results suggest that some forms are more tightly coupled to function than others in the prelinguistic and early linguistic period. Preliminary implications for developmental theory, future research, and clinical applications are discussed. Larger, longitudinal studies with typical and atypical populations and stricter methodological controls are needed to validate these findings.

  4. Steroid-dependent auditory plasticity for the enhancement of acoustic communication: recent insights from a vocal teleost fish

    OpenAIRE

    Joseph A Sisneros

    2009-01-01

    The vocal plainfin midshipman fish (Porichthys notatus) has become an excellent model for identifying neural mechanisms of auditory perception that may be shared by all vertebrates. Recent neuroethological studies of the midshipman fish have yielded strong evidence for the steroid-dependent modulation of hearing sensitivity that leads to enhanced coupling of sender and receiver in this vocal-acoustic communication system. Previous work shows that non-reproductive females treated with either t...

  5. Detection of the Vibration Signal from Human Vocal Folds Using a 94-GHz Millimeter-Wave Radar

    Science.gov (United States)

    Chen, Fuming; Li, Sheng; Zhang, Yang; Wang, Jianqi

    2017-01-01

    The detection of the vibration signal from human vocal folds provides essential information for studying human phonation and diagnosing voice disorders. Doppler radar technology has enabled the noncontact measurement of the human-vocal-fold vibration. However, existing systems must be placed in close proximity to the human throat and detailed information may be lost because of the low operating frequency. In this paper, a long-distance detection method, involving the use of a 94-GHz millimeter-wave radar sensor, is proposed for detecting the vibration signals from human vocal folds. An algorithm that combines empirical mode decomposition (EMD) and the auto-correlation function (ACF) method is proposed for detecting the signal. First, the EMD method is employed to suppress the noise of the radar-detected signal. Further, the ratio of the energy and entropy is used to detect voice activity in the radar-detected signal, following which, a short-time ACF is employed to extract the vibration signal of the human vocal folds from the processed signal. For validating the method and assessing the performance of the radar system, a vibration measurement sensor and microphone system are additionally employed for comparison. The experimental results obtained from the spectrograms, the vibration frequency of the vocal folds, and coherence analysis demonstrate that the proposed method can effectively detect the vibration of human vocal folds from a long detection distance. PMID:28282892

  6. Ultrasonic communication in rats: effects of morphine and naloxone on vocal and behavioral responses to playback of 50-kHz vocalizations.

    Science.gov (United States)

    Wöhr, Markus; Schwarting, Rainer K W

    2009-12-01

    Rats emit ultrasonic vocalizations and it was hypothesized that these vocalizations have an important role in intra-specific communication. Recently, we demonstrated that playback of 50-kHz ultrasonic vocalizations can induce social approach, indicating that 50-kHz calls can serve to (re)establish or to maintain social contact. It is known that endogenous opioids are implicated in the regulation of social behavior, particularly in rough and tumble play. Here, we tested whether administration of opioid ligands can affect social approach in response to playback of 50-kHz calls in juvenile and adult rats. Rats were either treated with 1mg/kg naloxone, 1mg/kg morphine, or with saline vehicle. Administration of opioid ligands affected social approach at both ages. Specifically, in juvenile and adult rats, social approach displayed in response to playback of 50-kHz calls was reduced in case of naloxone treatment, but enhanced with morphine. Furthermore, juvenile rats treated with saline or morphine emitted a substantial amount of ultrasonic vocalizations in response to the playback of 50-kHz calls. Such ultrasonic calling was not seen in naloxone treated rats. Importantly, these drug-dependent differences were stimulus-specific, i.e. seen only in response to playback of 50-kHz calls and not in response to playback of background noise. The present finding that opioid ligands can affect social approach and ultrasonic vocalizations induced by playback of 50-kHz calls, indicates that an important feature of social interaction in rats, namely ultrasonic communication, is at least partially regulated by endogenous opioids.

  7. Neural Network Communications Signal Processing

    Science.gov (United States)

    1994-08-01

    Technical Information Report for the Neural Network Communications Signal Processing Program, CDRL A003, 31 March 1993. Software Development Plan for...track changing jamming conditions to provide the decoder with the best log- likelihood ratio metrics at a given time. As part of our development plan we...Artificial Neural Networks (ICANN-91) Volume 2, June 24-28, 1991, pp. 1677-1680. Kohonen, Teuvo, Raivio, Kimmo, Simula, Oli, Venta , 011i, Henriksson

  8. Prosody Signals the Emergence of Intentional Communication in the First Year of Life: Evidence from Catalan-Babbling Infants

    Science.gov (United States)

    Esteve-Gibert, Nuria; Prieto, Pilar

    2013-01-01

    There is considerable debate about whether early vocalizations mimic the target language and whether prosody signals emergent intentional communication. A longitudinal corpus of four Catalan-babbling infants was analyzed to investigate whether children use different prosodic patterns to distinguish communicative from investigative vocalizations…

  9. Honest signaling and oxidative stress: the special case of avian acoustic communication

    Directory of Open Access Journals (Sweden)

    Stefania eCasagrande

    2016-05-01

    Full Text Available Much research on animal communication has addressed how costs or constraints determined by the oxidative status of an individual can assure the honesty of visual signals, such as sexually selected color ornaments. However, acoustic communication has been largely overlooked in this respect. Here, we describe the few available studies that have considered the role of oxidative status in mediating vocal behavior in adult and nestling birds. Further, we discuss the theoretical principles of how the honesty of avian acoustic signals may be maintained by an organism’s oxidative status. We here distinguish between studies that considered songs and begging calls as indicators of oxidative status and studies where vocalizations were assumed to be the source of oxidative costs. We outline experimental and methodological issues related to the study of bird vocalizations and oxidative stress and describe opportunities for future work in this field of research. Investigating the interactions between acoustic signals and redox state may help address some unresolved questions in avian vocalization, thereby increasing our understanding of the evolutionary pressures shaping animal communication. Finally, we argue that it will be important to extend this line of research beyond birds and include other taxa as well.

  10. Aeroelastic flutter of feathers, flight and the evolution of non-vocal communication in birds.

    Science.gov (United States)

    Clark, Christopher J; Prum, Richard O

    2015-11-01

    Tonal, non-vocal sounds are widespread in both ordinary bird flight and communication displays. We hypothesized these sounds are attributable to an aerodynamic mechanism intrinsic to flight feathers: aeroelastic flutter. Individual wing and tail feathers from 35 taxa (from 13 families) that produce tonal flight sounds were tested in a wind tunnel. In the wind tunnel, all of these feathers could flutter and generate tonal sound, suggesting that the capacity to flutter is intrinsic to flight feathers. This result implies that the aerodynamic mechanism of aeroelastic flutter is potentially widespread in flight of birds. However, the sounds these feathers produced in the wind tunnel replicated the actual flight sounds of only 15 of the 35 taxa. Of the 20 negative results, we hypothesize that 10 are false negatives, as the acoustic form of the flight sound suggests flutter is a likely acoustic mechanism. For the 10 other taxa, we propose our negative wind tunnel results are correct, and these species do not make sounds via flutter. These sounds appear to constitute one or more mechanism(s) we call 'wing whirring', the physical acoustics of which remain unknown. Our results document that the production of non-vocal communication sounds by aeroelastic flutter of flight feathers is widespread in birds. Across all birds, most evolutionary origins of wing- and tail-generated communication sounds are attributable to three mechanisms: flutter, percussion and wing whirring. Other mechanisms of sound production, such as turbulence-induced whooshes, have evolved into communication sounds only rarely, despite their intrinsic ubiquity in ordinary flight.

  11. The Acoustic Structure and Information Content of Female Koala Vocal Signals.

    Directory of Open Access Journals (Sweden)

    Benjamin D Charlton

    Full Text Available Determining the information content of animal vocalisations can give valuable insights into the potential functions of vocal signals. The source-filter theory of vocal production allows researchers to examine the information content of mammal vocalisations by linking variation in acoustic features with variation in relevant physical characteristics of the caller. Here I used a source-filter theory approach to classify female koala vocalisations into different call-types, and determine which acoustic features have the potential to convey important information about the caller to other conspecifics. A two-step cluster analysis classified female calls into bellows, snarls and tonal rejection calls. Additional results revealed that female koala vocalisations differed in their potential to provide information about a given caller's phenotype that may be of importance to receivers. Female snarls did not contain reliable acoustic cues to the caller's identity and age. In contrast, female bellows and tonal rejection calls were individually distinctive, and the tonal rejection calls of older female koalas had consistently lower mean, minimum and maximum fundamental frequency. In addition, female bellows were significantly shorter in duration and had higher fundamental frequency, formant frequencies, and formant frequency spacing than male bellows. These results indicate that female koala vocalisations have the potential to signal the caller's identity, age and sex. I go on to discuss the anatomical basis for these findings, and consider the possible functional relevance of signalling this type of information in the koala's natural habitat.

  12. Vocal ontogeny in neotropical singing mice (Scotinomys.

    Directory of Open Access Journals (Sweden)

    Polly Campbell

    Full Text Available Isolation calls produced by dependent young are a fundamental form of communication. For species in which vocal signals remain important to adult communication, the function and social context of vocal behavior changes dramatically with the onset of sexual maturity. The ontogenetic relationship between these distinct forms of acoustic communication is surprisingly under-studied. We conducted a detailed analysis of vocal development in sister species of Neotropical singing mice, Scotinomys teguina and S. xerampelinus. Adult singing mice are remarkable for their advertisement songs, rapidly articulated trills used in long-distance communication; the vocal behavior of pups was previously undescribed. We recorded 30 S. teguina and 15 S. xerampelinus pups daily, from birth to weaning; 23 S. teguina and 11 S. xerampelinus were recorded until sexual maturity. Like other rodent species with poikilothermic young, singing mice were highly vocal during the first weeks of life and stopped vocalizing before weaning. Production of first advertisement songs coincided with the onset of sexual maturity after a silent period of ≧2 weeks. Species differences in vocal behavior emerged early in ontogeny and notes that comprise adult song were produced from birth. However, the organization and relative abundance of distinct note types was very different between pups and adults. Notably, the structure, note repetition rate, and intra-individual repeatability of pup vocalizations did not become more adult-like with age; the highly stereotyped structure of adult song appeared de novo in the first songs of young adults. We conclude that, while the basic elements of adult song are available from birth, distinct selection pressures during maternal dependency, dispersal, and territorial establishment favor major shifts in the structure and prevalence of acoustic signals. This study provides insight into how an evolutionarily conserved form of acoustic signaling provides

  13. Rodent ultrasonic communication: Male prosocial 50-kHz ultrasonic vocalizations elicit social approach behavior in female rats (Rattus norvegicus).

    Science.gov (United States)

    Willadsen, Maria; Seffer, Dominik; Schwarting, Rainer K W; Wöhr, Markus

    2014-02-01

    Rats emit distinct types of ultrasonic vocalizations (USV), which serve as situation-dependent affective signals with important communicative functions. Low-frequency 22-kHz USV typically occur in aversive situations, such as social defeat, whereas high-frequency 50-kHz USV can be observed in appetitive situations, like rough-and-tumble-play in juveniles or mating in adults. The 2 main USV types serve distinct communicative functions and induce call-specific behavioral responses in the receiver. While 22-kHz USV probably serve as alarm calls, 50-kHz USV appear to serve a prosocial communicative function in the sexual and the nonsexual context. In the sexual context, however, this view has recently been challenged by playback studies where only very limited behavioral changes were observed in response to prosocial 50-kHz USV. The aim of the present study was therefore to test whether female rats display social approach behavior in response to male prosocial 50-kHz USV by means of our established playback paradigm. To this aim, we exposed female rats to playback of the following 2 acoustic stimuli: (a) natural male 50-kHz USV and (b) time- and amplitude-matched white noise, with the latter serving as acoustic control for novelty-induced changes in behavior not linked to the communicative function of male prosocial 50-kHz USV. Our present findings show that female rats display high levels of social approach behavior in response to male prosocial 50-kHz USV, but not time- and amplitude-matched white noise, supporting the conclusion that male prosocial 50-kHz USV are likely to play an important role in establishing social proximity and possibly regulate mating behavior.

  14. Affective communication in rodents: ultrasonic vocalizations as a tool for research on emotion and motivation.

    Science.gov (United States)

    Wöhr, Markus; Schwarting, Rainer K W

    2013-10-01

    Mice and rats emit and perceive calls in the ultrasonic range, i.e., above the human hearing threshold of about 20 kHz: so-called ultrasonic vocalizations (USV). Juvenile and adult rats emit 22-kHz USV in aversive situations, such as predator exposure and fighting or during drug withdrawal, whereas 50-kHz USV occur in appetitive situations, such as rough-and-tumble play and mating or in response to drugs of abuse, e.g., amphetamine. Aversive 22-kHz USV and appetitive 50-kHz USV serve distinct communicative functions. Whereas 22-kHz USV induce freezing behavior in the receiver, 50-kHz USV lead to social approach behavior. These opposite behavioral responses are paralleled by distinct patterns of brain activation. Freezing behavior in response to 22-kHz USV is paralleled by increased neuronal activity in brain areas regulating fear and anxiety, such as the amygdala and periaqueductal gray, whereas social approach behavior elicited by 50-kHz USV is accompanied by reduced activity levels in the amygdala but enhanced activity in the nucleus accumbens, a brain area implicated in reward processing. These opposing behavioral responses, together with distinct patterns of brain activation, particularly the bidirectional tonic activation or deactivation of the amygdala elicited by 22-kHz and 50-kHz USV, respectively, concur with a wealth of behavioral and neuroimaging studies in humans involving emotionally salient stimuli, such as fearful and happy facial expressions. Affective ultrasonic communication therefore offers a translational tool for studying the neurobiology underlying socio-affective communication. This is particularly relevant for rodent models of neurodevelopmental disorders characterized by social and communication deficits, such as autism and schizophrenia.

  15. The Public Sphere in Emerging Infectious Disease Communication: Recipient or Active and Vocal Partner?

    Science.gov (United States)

    Gesser-Edelsburg, Anat; Shir-Raz, Yaffa; Walter, Nathan; Mordini, Emilio; Dimitriou, Dimitris; James, James J; Green, Manfred S

    2015-08-01

    Recent years have seen advances in theories and models of risk and crisis communication, with a focus on emerging epidemic infection. Nevertheless, information flow remains unilateral in many countries and does not take into account the public's polyvocality and the fact that its opinions and knowledge often "compete" with those of health authorities. This article addresses the challenges organizations face in communicating with the public sphere. Our theoretical approach is conceptualized through a framework that focuses on the public sphere and that builds upon existing guidelines and studies in the context of health and pandemics. We examine how health organizations cope with the public's transformation from recipients to an active and vocal entity, ie, how and to what extent health organizations address the public's anxiety and concerns arising in the social media during outbreaks. Although international organizations have aspired to relate to the public as a partner, this article identifies notable gaps. Organizations must involve the public throughout the crisis and conduct dialogues free of prejudices, paternalism, and preconceptions. Thereby, they can impart precise and updated information reflecting uncertainty and considering cultural differences to build trust and facilitate cooperation with the public sphere.

  16. Wing, tail, and vocal contributions to the complex acoustic signals of courting Calliope hummingbirds

    Directory of Open Access Journals (Sweden)

    Christopher James CLARK

    2011-04-01

    Full Text Available Multi-component signals contain multiple signal parts expressed in the same physical modality. One way to identify individual components is if they are produced by different physical mechanisms. Here, I studied the mechanisms generating acoustic signals in the courtship displays of the Calliope hummingbird Stellula calliope. Display dives consisted of three synchronized sound elements, a high-frequency tone (hft, a low frequency tone (lft, and atonal sound pulses (asp, which were then followed by a frequency-modulated fall. Manipulating any of the rectrices (tail-feathers of wild males impaired production of the lft and asp but not the hft or fall, which are apparently vocal. I tested the sound production capabilities of the rectrices in a wind tunnel. Single rectrices could generate the lft but not the asp, whereas multiple rectrices tested together produced sounds similar to the asp when they fluttered and collided with their neighbors percussively, representing a previously unknown mechanism of sound production. During the shuttle display, a trill is generated by the wings during pulses in which the wingbeat frequency is elevated to 95 Hz, 40% higher than the typical hovering wingbeat frequency. The Calliope hummingbird courtship displays include sounds produced by three independent mechanisms, and thus include a minimum of three acoustic signal components. These acoustic mechanisms have different constraints and thus potentially contain different messages. Producing multiple acoustic signals via multiple mechanisms may be a way to escape the constraints present in any single mechanism [Current Zoology 57 (2: 187–196, 2011].

  17. Behavioural innovation and cultural transmission of communication signal in black howler monkeys.

    Science.gov (United States)

    Briseño-Jaramillo, M; Estrada, A; Lemasson, A

    2015-08-25

    Social traditions based on communication signals are widespread in birds, cetaceans and humans, but surprisingly rare in nonhuman primates known for having genetically-determined vocal repertoires. This study presents the first description of a singular case of behaviour associated with calling (placing a hand in front of the mouth while vocalizing: HFM) in black howler monkeys. We showed, first, that HFM was found only in a subset of the groups observed, at the same geographical location, and was age- and sex-specific. There was an audience effect on HFM, with highest rates when a neighbouring group was visible. HFM was non-randomly combined with audio-visual signals and always performed while roaring. High HFM rates triggered more vocal responses from group members and male neighbours, and HFM signalers temporally synchronized their behaviour in a predictable way. Finally, the positioning of the hand systematically modified the call's auditory structure. Altogether these results support the idea that HFM is an innovated, culturally transmitted communication signal that may play a role in inter-group competition and intra-group cohesion. This study opens new lines of research about how nonhuman primates developed strategies to overcome their constraints in acoustic plasticity very early in the primate lineage.

  18. Cognitive Vocal Program applied to individuals with signals presbylarynx: preliminary results.

    Science.gov (United States)

    Nemr, Katia; Souza, Glaucia Verena Sampaio de; Simões-Zenari, Marcia; Tsuji, Domingos Hiroshi; Hachiya, Adriana; Cordeiro, Gislaine Ferro; Nunes, Guilherme Pecoraro; Dajer, María Eugenia

    2014-01-01

    To propose and verify the feasibility of a vocal program intervention in patients with presbylarynx signs with or without vocal complaints. Among 20 elder participants of the current research, 3 female patients with median age of 67 years were chosen for the pilot study. Laryngological examination, vocal recording with CAPE-V (Consensus Auditory-Perceptual Evaluation of Voice) protocol, and Screening Protocol of Risk of Dysphonia (SPRD) were conducted before and after the program intervention. They joined the Cognitive Vocal Program for presbyphonia based on the genetic epistemology by Jean Piaget associated with vocal techniques based on scientific literature. This program is structured with six sessions and each one of them is focused in different aspects of vocal production. After the program intervention, some aspects such as loudness, coordination between breathing and speaking, accuracy in articulatory movements, jitter, and harmonics-to-noise ratio improved with parameters within the expected range for the age group. Three female participants were observed for better vocal quality, higher fundamental frequency, and better maximum phonation time. In two cases, tension related to loudness elevation and better scores on SPRD was observed. Using by high-speed laryngeal image, we also observed reduction of presbylarynx signs, and remarkable improvement in glottis closure competence and mucosal wave movement of the patients with and without vocal complaints. The preliminary results suggest encouraging prospects for the proposal with improvement in the aspects analyzed. This program was well designed and did not require any further adjustments.

  19. Wing,tail,and vocal contributions to the complex acoustic signals of courting Calliope hummingbirds

    Institute of Scientific and Technical Information of China (English)

    Christopher James CLARK

    2011-01-01

    Multi-component signals contain multiple signal parts expressed in the same physical modality.One way to identify individual components is if they are produced by different physical mechanisms.Here,I studied the mechanisms generating acoustic signais in the courtship displays of the Calliope hummingbird Stellula calliope.Display dives consisted of three synchronized sound elements,a high-frequency tone(hft),a low frequency tone(lft),and atonal sound pulses(asp),which were then followed by a frequency-modulaled fall.Manipulating any of the rectrices(tail-feathers)of wild males impaired production of the lft and asp,but not the hft or fall,which are apparently vocal.I tested the sound production capabilities of the rectrices in a wind tuunel.Single rectrices could generate the lft but not the asp,whereas multiple rectrices tested together produced sounds similar to the asp when they fluttered and collided with their neighbors percussively,representing a previously unknown mechanism of sound production.During the shuttle display,a trill is generated by the wings during pulses in which the wingbeat frequency is elevated to 95 Hz,40% higher than the typical hovering wingbeat frequency.Tbe Caillope hummingbird courtship displays include sounds produced by three independent mechauisms,and thus include a minimum of three acoustic signal components.These acoustic mechanisms have different constraints and thus potentially contain different messages.Producing multiple acoustic signals via multiple mechanisms may be a way to escape the constraints present in any single mechanism.

  20. Dopamine-sensitive signaling mediators modulate psychostimulant-induced ultrasonic vocalization behavior in rats.

    Science.gov (United States)

    Williams, Stacey N; Undieh, Ashiwel S

    2016-01-01

    The mesolimbic dopamine system plays a major role in psychostimulant-induced ultrasonic vocalization (USV) behavior in rodents. Within this system, psychostimulants elevate synaptic concentrations of dopamine thereby leading to exaggerated activation of postsynaptic dopamine receptors within the D1-like and D2-like subfamilies. Dopamine receptor stimulation activate several transmembrane signaling systems and cognate intracellular mediators; downstream activation of transcription factors then conveys the information from receptor activation to appropriate modulation of cellular and physiologic functions. We previously showed that cocaine-induced USV behavior was associated with enhanced expression of the neurotrophin BDNF. Like cocaine, amphetamine also increases synaptic dopamine levels, albeit primarily through facilitating dopamine release. Therefore, in the present study we investigated whether amphetamine and cocaine similarly activate dopamine-linked signaling cascades to regulate intracellular mediators leading to induction of USV behavior. The results show that amphetamine increased the emission of 50 kHz USVs and this effect was blocked by SCH23390, a D1 receptor antagonist. Similar to cocaine, amphetamine increased BDNF protein expression in discrete brain regions, while pretreatment with K252a, a trkB neurotrophin receptor inhibitor, significantly reduced amphetamine-induced USV behavior. Inhibition of cyclic-AMP/PKA signaling with H89 or inhibition of PLC signaling with U73122 significantly blocked both the acute and subchronic amphetamine-induced USV behavior. In contrast, pharmacologic inhibition of either pathway enhanced cocaine-induced USV behavior. Although cocaine and amphetamine similarly modulate neurotrophin expression and USV, the molecular mechanisms by which these psychostimulants differentially activate dopamine receptor subtypes or other monoaminergic systems may be responsible for the distinct aspects of behavioral responses.

  1. Relationships Between Vocal Activity and Perception of Communicators in Small Group Interaction

    Science.gov (United States)

    Daley, John A.; And Others

    1977-01-01

    Discusses a study designed to investigate the relationships between vocal activity level and interpersonal attraction, perceived credibility, perceived homophily or interpersonal similarity and perceived power or ability to influence. (MH)

  2. Inverter communications using output signal

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, Patrick L.

    2017-02-07

    Technologies for communicating information from an inverter configured for the conversion of direct current (DC) power generated from an alternative source to alternating current (AC) power are disclosed. The technologies include determining information to be transmitted from the inverter over a power line cable connected to the inverter and controlling the operation of an output converter of the inverter as a function of the information to be transmitted to cause the output converter to generate an output waveform having the information modulated thereon.

  3. Automatic modulation recognition of communication signals

    CERN Document Server

    Azzouz, Elsayed Elsayed

    1996-01-01

    Automatic modulation recognition is a rapidly evolving area of signal analysis. In recent years, interest from the academic and military research institutes has focused around the research and development of modulation recognition algorithms. Any communication intelligence (COMINT) system comprises three main blocks: receiver front-end, modulation recogniser and output stage. Considerable work has been done in the area of receiver front-ends. The work at the output stage is concerned with information extraction, recording and exploitation and begins with signal demodulation, that requires accurate knowledge about the signal modulation type. There are, however, two main reasons for knowing the current modulation type of a signal; to preserve the signal information content and to decide upon the suitable counter action, such as jamming. Automatic Modulation Recognition of Communications Signals describes in depth this modulation recognition process. Drawing on several years of research, the authors provide a cr...

  4. Investigation into the response of the auditory and acoustic communications systems in the Beluga whale (Delphinapterus leucas) of the St. Lawrence River Estuary to noise, using vocal classification

    Science.gov (United States)

    Scheifele, Peter Martin

    2003-06-01

    Noise pollution has only recently become recognized as a potential danger to marine mammals in general, and to the Beluga Whale (Delphinapterus leucas) in particular. These small gregarious Odontocetes make extensive use of sound for social communication and pod cohesion. The St. Lawrence River Estuary is habitat to a small, critically endangered population of about 700 Beluga whales who congregate in four different sites in its upper estuary. The population is believed to be threatened by the stress of high-intensity, low frequency noise. One way to determine whether noise is having an effect on an animal's auditory ability might be to observe a natural and repeatable response of the auditory and vocal systems to varying noise levels. This can be accomplished by observing changes in animal vocalizations in response to auditory feedback. A response such as this observed in humans and some animals is known as the Lombard Vocal Response, which represents a reaction of the auditory system directly manifested by changes in vocalization level. In this research this population of Beluga Whales was tested to determine whether a vocalization-as-a-function-of-noise phenomenon existed by using Hidden Markhov "classified" vocalizations as targets for acoustical analyses. Correlation and regression analyses indicated that the phenomenon does exist and results of a human subjects experiment along with results from other animal species known to exhibit the response strongly implicate the Lombard Vocal Response in the Beluga.

  5. Communication Impairment in Ultrasonic Vocal Repertoire during the Suckling Period of Cd157 Knockout Mice: Transient Improvement by Oxytocin.

    Science.gov (United States)

    Lopatina, Olga L; Furuhara, Kazumi; Ishihara, Katsuhiko; Salmina, Alla B; Higashida, Haruhiro

    2017-01-01

    Communication consists of social interaction, recognition, and information transmission. Communication ability is the most affected component in children with autism spectrum disorder (ASD). Recently, we reported that the CD157/BST1 gene is associated with ASD, and that CD157 knockout (Cd157(-/-)) mice display severe impairments in social behavior that are improved by oxytocin (OXT) treatment. Here, we sought to determine whether Cd157(-/-) mice can be used as a suitable model for communication deficits by measuring ultrasonic vocalizations (USVs), especially in the early developmental stage. Call number produced in pups due to isolation from dams was higher at postnatal day (PND) 3 in knockout pups than wild-type mice, but was lower at PNDs 7 and 10. Pups of both genotypes had similarly limited voice repertoires at PND 3. Later on, at PNDs 7 and 10, while wild-type pups emitted USVs consisting of six different syllable types, knockout pups vocalized with only two types. This developmental impairment in USV emission was rescued within 30 min by intraperitoneal OXT treatment, but quickly returned to control levels after 120 min, showing a transient effect of OXT. USV impairment was partially observed in Cd157(+/-) heterozygous mice, but not in Cd157(-/-) adult male mice examined while under courtship. These results demonstrate that CD157 gene deletion results in social communication insufficiencies, and suggests that CD157 is likely involved in acoustic communication. This unique OXT-sensitive developmental delay in Cd157(-/-) pups may be a useful model of communicative interaction impairment in ASD.

  6. Communication Impairment in Ultrasonic Vocal Repertoire during the Suckling Period of Cd157 Knockout Mice: Transient Improvement by Oxytocin

    Directory of Open Access Journals (Sweden)

    Olga L. Lopatina

    2017-05-01

    Full Text Available Communication consists of social interaction, recognition, and information transmission. Communication ability is the most affected component in children with autism spectrum disorder (ASD. Recently, we reported that the CD157/BST1 gene is associated with ASD, and that CD157 knockout (Cd157−/− mice display severe impairments in social behavior that are improved by oxytocin (OXT treatment. Here, we sought to determine whether Cd157−/− mice can be used as a suitable model for communication deficits by measuring ultrasonic vocalizations (USVs, especially in the early developmental stage. Call number produced in pups due to isolation from dams was higher at postnatal day (PND 3 in knockout pups than wild-type mice, but was lower at PNDs 7 and 10. Pups of both genotypes had similarly limited voice repertoires at PND 3. Later on, at PNDs 7 and 10, while wild-type pups emitted USVs consisting of six different syllable types, knockout pups vocalized with only two types. This developmental impairment in USV emission was rescued within 30 min by intraperitoneal OXT treatment, but quickly returned to control levels after 120 min, showing a transient effect of OXT. USV impairment was partially observed in Cd157+/− heterozygous mice, but not in Cd157−/− adult male mice examined while under courtship. These results demonstrate that CD157 gene deletion results in social communication insufficiencies, and suggests that CD157 is likely involved in acoustic communication. This unique OXT-sensitive developmental delay in Cd157−/− pups may be a useful model of communicative interaction impairment in ASD.

  7. Sensing, Signal Processing, and Communication for WBANs

    Institute of Scientific and Technical Information of China (English)

    Seyyed Hamed Fouladi; Ral ChvezSantiago; Pl Ander Floor; Ilangko Balasingham; Tor ARamstad

    2014-01-01

    A wireless body area network (WBAN) enables real-time monitoring of physiological signals and helps with the early detection of life-threatening diseases. WBAN nodes can be located on, inside, or in close proximity to the body in order to detect vital signals. Measurements from sensors are processed and transmitted over wireless channels. Issues in sensing, signal processing, and com-munication have to be addressed before WBAN can be implemented. In this paper, we survey recent advances in research on sig-nal processing for the sensor measurements, and we describe aspects of communication based on IEEE 802.15.6. We also discuss state-of-the-art WBAN channel modeling in all the frequencies specified by IEEE 802.15.6 as well as the need for new channel models for new different frequencies.

  8. Vocal coordination and vocal imitation: a role for mirror neurons?

    Science.gov (United States)

    Newman, John D

    2014-04-01

    Some birds and mammals have vocal communication systems in which coordination between individuals is important. Examples would include duetting or antiphonal calling in some birds and mammals, rapid exchanges of the same vocalization, and vocal exchanges between paired individuals and other nearby pairs. Mirror neurons may play a role in such systems but become functional only after experience.

  9. Laryngeal biomechanics and vocal communication in the squirrel monkey (Saimiri boliviensis)

    Science.gov (United States)

    Brown, Charles H.; Alipour, Fariborz; Berry, David A.; Montequin, Douglas

    2003-04-01

    The larynges of eight squirrel monkeys were harvested, dissected, mounted on a pseudotracheal tube, and phonated using compressed air. Patterns of vocal fold oscillation were compared with sound spectrograms of calls recorded from monkeys in our colony. Four different regimes of vocal fold activation were identified. Regime 1 resembled typical human vowel production, with regular vocal-fold vibration, a prominent fundamental frequency, and an accompanying series of harmonic overtones. This regime is likely to give rise to squirrel monkey ``cackles,'' as well as a variety of other harmonically structured calls. In regime 2, the pattern of vibrations exhibited the presence of two or more unrelated frequencies (biphonation). This regime of glottal activity resembled the biphonation observed in many exemplars of ``twitter'' and ``kecker'' calls. The vocal folds oscillated continuously in regime 3, but produced glottal pulses whose amplitudes waxed and waned rhythmically. This phenomenon resulted in the percept of a series of discrete pulses, and may give rise to ``errs,'' ``churrs,'' and other calls composed of a rapid sequence of acoustic elements. In regime 4, the period of each oscillation was quasi-irregular. Shrieks and other broadband calls or call elements that lack an apparent fundamental frequency may be produced in this manner.

  10. Evidence of auditory insensitivity to vocalization frequencies in two frogs

    DEFF Research Database (Denmark)

    Goutte, Sandra; Mason, Matthew J; Christensen-Dalsgaard, Jakob

    2017-01-01

    The emergence and maintenance of animal communication systems requires the co-evolution of signal and receiver. Frogs and toads rely heavily on acoustic communication for coordinating reproduction and typically have ears tuned to the dominant frequency of their vocalizations, allowing discriminat...

  11. 3rd International Conference on Communications, Signal Processing, and Systems

    CERN Document Server

    Liang, Qilian; Wang, Wei; Zhang, Baoju; Pi, Yiming

    2015-01-01

    The Proceedings of The Third International Conference on Communications, Signal Processing, and Systems provides the state-of-art developments of communications, signal processing, and systems. This book is a collection of contributions from the conference and covers such topics as wireless communications, networks, systems, and signal processing for communications. The conference was held July 2014 in Hohhot, Inner Mongolia, China.

  12. Second International Conference on Communications, Signal Processing, and Systems

    CERN Document Server

    Mu, Jiasong; Wang, Wei; Liang, Qilian; Pi, Yiming

    2014-01-01

    The Proceedings of The Second International Conference on Communications, Signal Processing, and Systems provides the state-of-art developments of Communications, Signal Processing, and Systems. The conference covered such topics as wireless communications, networks, systems, signal processing for communications. This book is a collection of contributions coming out of The Second International Conference on Communications, Signal Processing, and Systems (CSPS) held September 2013 in Tianjin, China.

  13. Songbird: a unique animal model for studying the molecular basis of disorders of vocal development and communication.

    Science.gov (United States)

    Mori, Chihiro; Wada, Kazuhiro

    2015-01-01

    Like humans, songbirds are one of the few animal groups that learn vocalization. Vocal learning requires coordination of auditory input and vocal output using auditory feedback to guide one's own vocalizations during a specific developmental stage known as the critical period. Songbirds are good animal models for understand the neural basis of vocal learning, a complex form of imitation, because they have many parallels to humans with regard to the features of vocal behavior and neural circuits dedicated to vocal learning. In this review, we will summarize the behavioral, neural, and genetic traits of birdsong. We will also discuss how studies of birdsong can help us understand how the development of neural circuits for vocal learning and production is driven by sensory input (auditory information) and motor output (vocalization).

  14. Advanced Signal Processing for Wireless Multimedia Communications

    Directory of Open Access Journals (Sweden)

    Xiaodong Wang

    2000-01-01

    Full Text Available There is at present a worldwide effort to develop next-generation wireless communication systems. It is envisioned that many of the future wireless systems will incorporate considerable signal-processing intelligence in order to provide advanced services such as multimedia transmission. In general, wireless channels can be very hostile media through which to communicate, due to substantial physical impediments, primarily radio-frequency interference and time-arying nature of the channel. The need of providing universal wireless access at high data-rate (which is the aim of many merging wireless applications presents a major technical challenge, and meeting this challenge necessitates the development of advanced signal processing techniques for multiple-access communications in non-stationary interference-rich environments. In this paper, we present some key advanced signal processing methodologies that have been developed in recent years for interference suppression in wireless networks. We will focus primarily on the problem of jointly suppressing multiple-access interference (MAI and intersymbol interference (ISI, which are the limiting sources of interference for the high data-rate wireless systems being proposed for many emerging application areas, such as wireless multimedia. We first present a signal subspace approach to blind joint suppression of MAI and ISI. We then discuss a powerful iterative technique for joint interference suppression and decoding, so-called Turbo multiuser detection, that is especially useful for wireless multimedia packet communications. We also discuss space-time processing methods that employ multiple antennas for interference rejection and signal enhancement. Finally, we touch briefly on the problems of suppressing narrowband interference and impulsive ambient noise, two other sources of radio-frequency interference present in wireless multimedia networks.

  15. Vocal Imitation in Parrots Allows Addressing of Specific Individuals in a Dynamic Communication Network

    DEFF Research Database (Denmark)

    Balsby, T.J.S.; Momberg, J.V.; Dabelsteen, T.

    2012-01-01

    and faster than the other individual. This suggests that orange-fronted conures can use imitations of contact calls to address specific individuals of a flock. In the discussion we argue that the fission-fusion flock dynamics of many parrot species has been an important factor in evolving conures´ and other......Parrots in captivity are known for their ability to vocally imitate humans and recently it has been shown that wild-living orange-fronted conures are able to immediately imitate other individuals´ contact calls. The function of this exceptional ability to imitate remains unclear. However, orangeâ......€“fronted conures live in fission-fusion flocks where they encounter many different individuals every day, and it is possible that their vocal imitation ability is a flexible means to address a specific individual within a flock. We tested this via playback to short-term captive wild conures. Test birds were placed...

  16. Vocal imitation in parrots allows addressing of specific individuals in a dynamic communication network.

    Directory of Open Access Journals (Sweden)

    Thorsten J S Balsby

    Full Text Available Parrots in captivity are known for their ability to vocally imitate humans and recently it has been shown that wild-living orange-fronted conures are able to immediately imitate other individuals' contact calls. The function of this exceptional ability to imitate remains unclear. However, orange-fronted conures live in fission-fusion flocks where they encounter many different individuals every day, and it is possible that their vocal imitation ability is a flexible means to address a specific individual within a flock. We tested this via playback to short-term captive wild conures. Test birds were placed together in pairs in outdoor aviaries to form simple flocks. To simulate imitation of a specific individual these pairs received playback of contact calls that primarily imitate one of the two birds. Overall, individuals that received simulated vocal imitations of its calls responded more frequently and faster than the other individual. This suggests that orange-fronted conures can use imitations of contact calls to address specific individuals of a flock. In the discussion we argue that the fission-fusion flock dynamics of many parrot species has been an important factor in evolving conures' and other parrots' exceptional ability to imitate.

  17. Vocal imitation in parrots allows addressing of specific individuals in a dynamic communication network.

    Science.gov (United States)

    Balsby, Thorsten J S; Momberg, Jane Vestergaard; Dabelsteen, Torben

    2012-01-01

    Parrots in captivity are known for their ability to vocally imitate humans and recently it has been shown that wild-living orange-fronted conures are able to immediately imitate other individuals' contact calls. The function of this exceptional ability to imitate remains unclear. However, orange-fronted conures live in fission-fusion flocks where they encounter many different individuals every day, and it is possible that their vocal imitation ability is a flexible means to address a specific individual within a flock. We tested this via playback to short-term captive wild conures. Test birds were placed together in pairs in outdoor aviaries to form simple flocks. To simulate imitation of a specific individual these pairs received playback of contact calls that primarily imitate one of the two birds. Overall, individuals that received simulated vocal imitations of its calls responded more frequently and faster than the other individual. This suggests that orange-fronted conures can use imitations of contact calls to address specific individuals of a flock. In the discussion we argue that the fission-fusion flock dynamics of many parrot species has been an important factor in evolving conures' and other parrots' exceptional ability to imitate.

  18. Semiotic aspects of human nonverbal vocalizations: a functional imaging study.

    Science.gov (United States)

    Dietrich, Susanne; Hertrich, Ingo; Alter, Kai; Ischebeck, Anja; Ackermann, Hermann

    2007-12-03

    Humans produce a variety of distinct nonverbal vocalizations. Whereas affective bursts, for example, laughter, have an intrinsic communicative role bound to social behavior, vegetative sounds, for example, snoring, just signal autonomic-physiological states. However, the latter events, for example, belching, may also be used as intentional communicative actions (vocal gestures), characterized by an arbitrary culture-dependent sound-to-meaning (semiotic) relationship, comparable to verbal utterances. Using a decision task, hemodynamic responses to affective bursts, vegetative sounds, and vocal gestures were measured by means of functional magnetic resonance imaging. Affective bursts elicited activation of anterior left superior temporal gyrus. In contrast, arbitrary vocal gestures yielded hemodynamic reactions of the left temporo-parietal junction. Conceivably, a listener's interpretation of nonverbal utterances as intentional events depends upon a left-hemisphere temporo-parietal 'auditory-to-meaning interface' related to our mechanisms of speech processing.

  19. Radio Science from an Optical Communications Signal

    Science.gov (United States)

    Moision, Bruce; Asmar, Sami; Oudrhiri, Kamal

    2013-01-01

    NASA is currently developing the capability to deploy deep space optical communications links. This creates the opportunity to utilize the optical link to obtain range, doppler, and signal intensity estimates. These may, in turn, be used to complement or extend the capabilities of current radio science. In this paper we illustrate the achievable precision in estimating range, doppler, and received signal intensity of an non-coherent optical link (the current state-of-the-art for a deep-space link). We provide a joint estimation algorithm with performance close to the bound. We draw comparisons to estimates based on a coherent radio frequency signal, illustrating that large gains in either precision or observation time are possible with an optical link.

  20. 49 CFR 220.51 - Radio communications and signal indications.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Radio communications and signal indications. 220... RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD COMMUNICATIONS Radio and Wireless Communication Procedures § 220.51 Radio communications and signal indications. (a) No information may be...

  1. Cross-cultural recognition of basic emotions through nonverbal emotional vocalizations

    Science.gov (United States)

    Sauter, Disa A.; Eisner, Frank; Ekman, Paul; Scott, Sophie K.

    2010-01-01

    Emotional signals are crucial for sharing important information, with conspecifics, for example, to warn humans of danger. Humans use a range of different cues to communicate to others how they feel, including facial, vocal, and gestural signals. We examined the recognition of nonverbal emotional vocalizations, such as screams and laughs, across two dramatically different cultural groups. Western participants were compared to individuals from remote, culturally isolated Namibian villages. Vocalizations communicating the so-called “basic emotions” (anger, disgust, fear, joy, sadness, and surprise) were bidirectionally recognized. In contrast, a set of additional emotions was only recognized within, but not across, cultural boundaries. Our findings indicate that a number of primarily negative emotions have vocalizations that can be recognized across cultures, while most positive emotions are communicated with culture-specific signals. PMID:20133790

  2. Cross-cultural recognition of basic emotions through nonverbal emotional vocalizations.

    Science.gov (United States)

    Sauter, Disa A; Eisner, Frank; Ekman, Paul; Scott, Sophie K

    2010-02-09

    Emotional signals are crucial for sharing important information, with conspecifics, for example, to warn humans of danger. Humans use a range of different cues to communicate to others how they feel, including facial, vocal, and gestural signals. We examined the recognition of nonverbal emotional vocalizations, such as screams and laughs, across two dramatically different cultural groups. Western participants were compared to individuals from remote, culturally isolated Namibian villages. Vocalizations communicating the so-called "basic emotions" (anger, disgust, fear, joy, sadness, and surprise) were bidirectionally recognized. In contrast, a set of additional emotions was only recognized within, but not across, cultural boundaries. Our findings indicate that a number of primarily negative emotions have vocalizations that can be recognized across cultures, while most positive emotions are communicated with culture-specific signals.

  3. Vocal registers of the countertenor voice: Based on signals recorded and analyzed in VoceVista

    Science.gov (United States)

    Chenez, Raymond

    Today's countertenors possess vocal ranges similar to the mezzo-soprano, and are trained to sing with a vibrant, focused tone. Little research has been conducted on the registers of the countertenor voice. Advancement in vocal techniques in the countertenor voice from the late 20th century to the present has been rapid. This treatise attempts to define the registers of the countertenor voice, and is intended as a resource for singers and teachers. The voices of eleven North American countertenors were recorded and analyzed using VoceVista Pro software, which was developed and designed by Donald Miller. Through spectrographic and electroglottographic analysis, the registers of the countertenor voice were identified and outlined.

  4. Structural Classification of Wild Boar (Sus scrofa) Vocalizations.

    Science.gov (United States)

    Garcia, Maxime; Gingras, Bruno; Bowling, Daniel L; Herbst, Christian T; Boeckle, Markus; Locatelli, Yann; Fitch, W Tecumseh

    2016-04-01

    Determining whether a species' vocal communication system is graded or discrete requires definition of its vocal repertoire. In this context, research on domestic pig (Sus scrofa domesticus) vocalizations, for example, has led to significant advances in our understanding of communicative functions. Despite their close relation to domestic pigs, little is known about wild boar (Sus scrofa) vocalizations. The few existing studies, conducted in the 1970s, relied on visual inspections of spectrograms to quantify acoustic parameters and lacked statistical analysis. Here, we use objective signal processing techniques and advanced statistical approaches to classify 616 calls recorded from semi-free ranging animals. Based on four spectral and temporal acoustic parameters-quartile Q25, duration, spectral flux, and spectral flatness-extracted from a multivariate analysis, we refine and extend the conclusions drawn from previous work and present a statistically validated classification of the wild boar vocal repertoire into four call types: grunts, grunt-squeals, squeals, and trumpets. While the majority of calls could be sorted into these categories using objective criteria, we also found evidence supporting a graded interpretation of some wild boar vocalizations as acoustically continuous, with the extremes representing discrete call types. The use of objective criteria based on modern techniques and statistics in respect to acoustic continuity advances our understanding of vocal variation. Integrating our findings with recent studies on domestic pig vocal behavior and emotions, we emphasize the importance of grunt-squeals for acoustic approaches to animal welfare and underline the need of further research investigating the role of domestication on animal vocal communication.

  5. A comparative neurological approach to emotional expressions in primate vocalizations.

    Science.gov (United States)

    Gruber, Thibaud; Grandjean, Didier

    2017-02-01

    Different approaches from different research domains have crystallized debate over primate emotional processing and vocalizations in recent decades. On one side, researchers disagree about whether emotional states or processes in animals truly compare to those in humans. On the other, a long-held assumption is that primate vocalizations are innate communicative signals over which nonhuman primates have limited control and a mirror of the emotional state of the individuals producing them, despite growing evidence of intentional production for some vocalizations. Our goal is to connect both sides of the discussion in deciphering how the emotional content of primate calls compares with emotional vocal signals in humans. We focus particularly on neural bases of primate emotions and vocalizations to identify cerebral structures underlying emotion, vocal production, and comprehension in primates, and discuss whether particular structures or neuronal networks solely evolved for specific functions in the human brain. Finally, we propose a model to classify emotional vocalizations in primates according to four dimensions (learning, control, emotional, meaning) to allow comparing calls across species.

  6. Cross-cultural recognition of basic emotions through nonverbal emotional vocalizations

    OpenAIRE

    Sauter, D.; Eisner, F.; Ekman, P.; Scott, S.

    2010-01-01

    Emotional signals are crucial for sharing important information, with conspecifics, for example, to warn humans of danger. Humans use a range of different cues to communicate to others how they feel, including facial, vocal, and gestural signals. We examined the recognition of nonverbal emotional vocalizations, such as screams and laughs, across two dramatically different cultural groups. Western participants were compared to individuals from remote, culturally isolated Namibian villages. Voc...

  7. Implicitly perceived vocal attractiveness modulates prefrontal cortex activity.

    Science.gov (United States)

    Bestelmeyer, Patricia E G; Latinus, Marianne; Bruckert, Laetitia; Rouger, Julien; Crabbe, Frances; Belin, Pascal

    2012-06-01

    Social interactions involve more than "just" language. As important is a more primitive nonlinguistic mode of communication acting in parallel with linguistic processes and driving our decisions to a much higher degree than is generally suspected. Amongst the "honest signals" that influence our behavior is perceived vocal attractiveness. Not only does vocal attractiveness reflect important biological characteristics of the speaker, it also influences our social perceptions according to the "what sounds beautiful is good" phenomenon. Despite the widespread influence of vocal attractiveness on social interactions revealed by behavioral studies, its neural underpinnings are yet unknown. We measured brain activity while participants listened to a series of vocal sounds ("ah") and performed an unrelated task. We found that voice-sensitive auditory and inferior frontal regions were strongly correlated with implicitly perceived vocal attractiveness. While the involvement of auditory areas reflected the processing of acoustic contributors to vocal attractiveness ("distance to mean" and spectrotemporal regularity), activity in inferior prefrontal regions (traditionally involved in speech processes) reflected the overall perceived attractiveness of the voices despite their lack of linguistic content. These results suggest the strong influence of hidden nonlinguistic aspects of communication signals on cerebral activity and provide an objective measure of this influence.

  8. Convergent evolution of vocal cooperation without convergent evolution of brain size.

    Science.gov (United States)

    Borjon, Jeremy I; Ghazanfar, Asif A

    2014-01-01

    One pragmatic underlying successful vocal communication is the ability to take turns. Taking turns - a form of cooperation - facilitates the transmission of signals by reducing the amount of their overlap. This allows vocalizations to be better heard. Until recently, non-human primates were not thought of as particularly cooperative, especially in the vocal domain. We recently demonstrated that common marmosets (Callithrix jacchus), a small New World primate species, take turns when they exchange vocalizations with both related and unrelated conspecifics. As the common marmoset is distantly related to humans (and there is no documented evidence that Old World primates exhibit vocal turn taking), we argue that this ability arose as an instance of convergent evolution, and is part of a suite of prosocial behavioral tendencies. Such behaviors seem to be, at least in part, the outcome of the cooperative breeding strategy adopted by both humans and marmosets. Importantly, this suite of shared behaviors occurs without correspondence in encephalization. Marmoset vocal turn taking demonstrates that a large brain size and complex cognitive machinery is not needed for vocal cooperation to occur. Consistent with this idea, the temporal structure of marmoset vocal exchanges can be described in terms of coupled oscillator dynamics, similar to quantitative descriptions of human conversations. We propose a simple neural circuit mechanism that may account for these dynamics and, at its core, involves vocalization-induced reductions of arousal. Such a mechanism may underlie the evolution of vocal turn taking in both marmoset monkeys and humans. © 2014 S. Karger AG, Basel.

  9. Shaping communicative colour signals over evolutionary time

    Science.gov (United States)

    Oyola Morales, José R.; Vital-García, Cuauhcihuatl; Hews, Diana K.; Martins, Emília P.

    2016-01-01

    Many evolutionary forces can shape the evolution of communicative signals, and the long-term impact of each force may depend on relative timing and magnitude. We use a phylogenetic analysis to infer the history of blue belly patches of Sceloporus lizards, and a detailed spectrophotometric analysis of four species to explore the specific forces shaping evolutionary change. We find that the ancestor of Sceloporus had blue patches. We then focus on four species; the first evolutionary shift (captured by comparison of S. merriami and S. siniferus) represents an ancient loss of the belly patch by S. siniferus, and the second evolutionary shift, bounded by S. undulatus and S. virgatus, represents a more recent loss of blue belly patch by S. virgatus. Conspicuousness measurements suggest that the species with the recent loss (S. virgatus) is the least conspicuous. Results for two other species (S. siniferus and S. merriami) suggest that over longer periods of evolutionary time, new signal colours have arisen which minimize absolute contrast with the habitat while maximizing conspicuousness to a lizard receiver. Specifically, males of the species representing an ancient loss of blue patch (S. siniferus) are more conspicuous than are females in the UV, whereas S. merriami males have evolved a green element that makes their belly patches highly sexually dimorphic but no more conspicuous than the white bellies of S. merriami females. Thus, our results suggest that natural selection may act more immediately to reduce conspicuousness, whereas sexual selection may have a more complex impact on communicative signals through the introduction of new colours. PMID:28018661

  10. Vocal acrobatics in a Chinese frog, Amolops tormotus

    Science.gov (United States)

    Feng, Albert; Narins, Peter; Xu, Chun-He

    2002-06-01

    Although amphibians are highly vocal, they generally emit only a limited number of acoustic communication signals. We report here the extraordinarily rich vocal repertoire of Amolops tormotus, a ranid species in China. These frogs produce countless vocalizations, some of which share features of birdsong or primate calls, e.g., ultrasonic frequency components, multiple upward and downward FM sweeps, and sudden onset and offset of selective harmonic components within a call note. Frame-by-frame video analysis of the frog's calling behavior suggests the presence of two pairs of vocal sacs that may contribute to the remarkable call-note complexity in this species. Electronic supplementary material to this paper can be obtained by using the Springer LINK server located at http://dx.doi.org/10.1007/s00114-002-0335-x.

  11. Emancipation of the voice: Vocal complexity as a fitness indicator.

    Science.gov (United States)

    Locke, John L

    2017-02-01

    Although language is generally spoken, most evolutionary proposals say little about any changes that may have induced vocal control. Here I suggest that the interaction of two changes in our species-one in sociality, the other in life history-liberated the voice from its affective moorings, enabling it to serve as a fitness cue or signal. The modification of life history increased the helplessness of infants, thus their competition for care, pressuring them to emit, and parents (and others) to evaluate, new vocal cues in bids for attention. This change elaborated and formalized the care communication system that was used in infancy and, because of parental adoption of social criteria, extended it into childhood, supporting the extrafamilial relationships that intensify in those stages. The remodeling of life history, in conjunction with intensified sociality, also enhanced vocal signaling in adolescence-a second stage that is unique to humans-and adulthood. Building on the new vocal skills and fitness criteria that emerged earlier, I claim that males with ornamented speech enjoyed advantages in their pursuit of dominance and reproductive opportunities in evolutionary history, as they do today. There are implications of this scenario for the mechanistic level of vocal diversification. Today, intentionality plays a role both in the instrumental crying of infants and the modulated vocalizations of adults. In evolutionary history, I claim that in both cases, spontaneously emitted behavioral cues elicited perceptible responses, giving rise to strategic signals that were sent, and processed, under a new and fundamentally different neural regime.

  12. 基于功率谱和共振峰的母羊发声信号识别%Vocal signal recognition of ewes based on power spectrum and formant analysis method

    Institute of Scientific and Technical Information of China (English)

    宣传忠; 武佩; 马彦华; 张丽娜; 韩丁; 刘艳秋

    2015-01-01

    of the recognition mode. The results demonstrated that characteristic parameters of ewes’ vocal signals were obviously different under different stress behaviors. Furthermore, if BP recognition network was trained by formant parameters, the average correct recognition rate of ewes’ vocal signal was 85.3%, higher than AR power spectrum estimation parameters of 81.0%. When BP network was trained by a combination of above two kinds of characteristic parameters, the average correct recognition rate was 93.8%, which meant that the performance of the combination parameters was better than another two methods. However, the average false positive rate still reached 6.2% because ewes’ vocal signals under the same stress behavior had a certain degree of difference due to the different age and weight as well as sound volume strength. The results of this study also indicated that analysis of vocalization could be an indicator of different physiological conditions in sheep and may be an important role for understanding communications in ewes.%内蒙古及周边西部地区正在发展规模化种草设施圈养,这种养殖模式要求较高的福利化饲养水平。母羊在不同的应激行为下会发出不同的声信号,可以通过识别母羊发声信号去评价其健康状况和福利化养殖水平。该研究以成年小尾寒羊为例,通过无线语音数据采集卡,平均采集80只母羊在寻羔、饥饿和惊吓3种应激行为下的发声,用 Audacity软件共分割成1200句叫声信号,并用带通滤波和小波消噪进行预处理。每种应激行为下再随机选取200句发声信号,共计600句进行AR(auto-regressive)功率谱估计和共振峰分析,提取第1、2和3共振峰频率和6个代表性的功率谱估计频域参数:功率谱密度的平均值、几何平均值、中值、切尾平均值、平均绝对偏差值和四位分极差,同时也提取叫声信号的最大值、持续

  13. The effects of impulsivity and proactive inhibition on reactive inhibition and the go process: insights from vocal and manual stop signal tasks

    Science.gov (United States)

    Castro-Meneses, Leidy J.; Johnson, Blake W.; Sowman, Paul F.

    2015-01-01

    This study measured proactive and reactive response inhibition and their relationships with self-reported impulsivity. We examined the domains of both vocal and manual responding using a stop signal task (SST) with two stop probabilities: high and low probability stop (1/3 and 1/6 stops respectively). Our aim was to evaluate the effect stop probability would have on reactive and proactive inhibition. We tested 44 subjects and found that for the high compared to low probability stop signal condition, more proactive inhibition was evident and this was correlated with a reduction in the stop signal reaction time (SSRT). We found that reactive inhibition had a positive relationship with dysfunctional but not functional impulsivity in both vocal and manual domains of responding. These findings support the hypothesis that proactive inhibition may pre-activate the network for reactive inhibition. PMID:26500518

  14. The effects of impulsivity and proactive inhibition on reactive inhibition and the go process: insights from the stop signal task of vocal and manual responses

    Directory of Open Access Journals (Sweden)

    Leidy Janeth Castro-Meneses

    2015-10-01

    Full Text Available This study measured proactive and reactive response inhibition and their relationships with self-reported impulsivity. We examined the domains of both vocal and manual responding using a stop signal task (SST with two stop probabilities: high and low probability stop (1/3 and 1/6 stops respectively. Our aim was to evaluate the effect stop probability would have on reactive and proactive inhibition. We tested 44 subjects and found that for the high compared to low probability stop signal condition, more proactive inhibition was evident and this was correlated with a reduction in the stop signal reaction time (SSRT. We found that reactive inhibition had a positive relationship with dysfunctional but not functional impulsivity in both vocal and manual domains of responding. These findings support the hypothesis that proactive inhibition may pre-activate the network for reactive inhibition.

  15. An Investigation of Extinction-Induced Vocalizations

    Science.gov (United States)

    Valentino, Amber L.; Shillingsburg, M. Alice; Call, Nathan A.; Burton, Britney; Bowen, Crystal N.

    2011-01-01

    Children with autism have significant communication delays. Although some children develop vocalizations through shaping and differential reinforcement, others rarely exhibit vocalizations, and alternative methods are targeted in intervention. However, vocal language often remains a goal for caregivers and clinicians. Thus, strategies to increase…

  16. Distinct Neural Activities in Premotor Cortex during Natural Vocal Behaviors in a New World Primate, the Common Marmoset (Callithrix jacchus).

    Science.gov (United States)

    Roy, Sabyasachi; Zhao, Lingyun; Wang, Xiaoqin

    2016-11-30

    Although evidence from human studies has long indicated the crucial role of the frontal cortex in speech production, it has remained uncertain whether the frontal cortex in nonhuman primates plays a similar role in vocal communication. Previous studies of prefrontal and premotor cortices of macaque monkeys have found neural signals associated with cue- and reward-conditioned vocal production, but not with self-initiated or spontaneous vocalizations (Coudé et al., 2011; Hage and Nieder, 2013), which casts doubt on the role of the frontal cortex of the Old World monkeys in vocal communication. A recent study of marmoset frontal cortex observed modulated neural activities associated with self-initiated vocal production (Miller et al., 2015), but it did not delineate whether these neural activities were specifically attributed to vocal production or if they may result from other nonvocal motor activity such as orofacial motor movement. In the present study, we attempted to resolve these issues and examined single neuron activities in premotor cortex during natural vocal exchanges in the common marmoset (Callithrix jacchus), a highly vocal New World primate. Neural activation and suppression were observed both before and during self-initiated vocal production. Furthermore, by comparing neural activities between self-initiated vocal production and nonvocal orofacial motor movement, we identified a subpopulation of neurons in marmoset premotor cortex that was activated or suppressed by vocal production, but not by orofacial movement. These findings provide clear evidence of the premotor cortex's involvement in self-initiated vocal production in natural vocal behaviors of a New World primate.

  17. Convergent differential regulation of parvalbumin in the brains of vocal learners.

    Directory of Open Access Journals (Sweden)

    Erina Hara

    Full Text Available Spoken language and learned song are complex communication behaviors found in only a few species, including humans and three groups of distantly related birds--songbirds, parrots, and hummingbirds. Despite their large phylogenetic distances, these vocal learners show convergent behaviors and associated brain pathways for vocal communication. However, it is not clear whether this behavioral and anatomical convergence is associated with molecular convergence. Here we used oligo microarrays to screen for genes differentially regulated in brain nuclei necessary for producing learned vocalizations relative to adjacent brain areas that control other behaviors in avian vocal learners versus vocal non-learners. A top candidate gene in our screen was a calcium-binding protein, parvalbumin (PV. In situ hybridization verification revealed that PV was expressed significantly higher throughout the song motor pathway, including brainstem vocal motor neurons relative to the surrounding brain regions of all distantly related avian vocal learners. This differential expression was specific to PV and vocal learners, as it was not found in avian vocal non-learners nor for control genes in learners and non-learners. Similar to the vocal learning birds, higher PV up-regulation was found in the brainstem tongue motor neurons used for speech production in humans relative to a non-human primate, macaques. These results suggest repeated convergent evolution of differential PV up-regulation in the brains of vocal learners separated by more than 65-300 million years from a common ancestor and that the specialized behaviors of learned song and speech may require extra calcium buffering and signaling.

  18. Convergent differential regulation of parvalbumin in the brains of vocal learners.

    Science.gov (United States)

    Hara, Erina; Rivas, Miriam V; Ward, James M; Okanoya, Kazuo; Jarvis, Erich D

    2012-01-01

    Spoken language and learned song are complex communication behaviors found in only a few species, including humans and three groups of distantly related birds--songbirds, parrots, and hummingbirds. Despite their large phylogenetic distances, these vocal learners show convergent behaviors and associated brain pathways for vocal communication. However, it is not clear whether this behavioral and anatomical convergence is associated with molecular convergence. Here we used oligo microarrays to screen for genes differentially regulated in brain nuclei necessary for producing learned vocalizations relative to adjacent brain areas that control other behaviors in avian vocal learners versus vocal non-learners. A top candidate gene in our screen was a calcium-binding protein, parvalbumin (PV). In situ hybridization verification revealed that PV was expressed significantly higher throughout the song motor pathway, including brainstem vocal motor neurons relative to the surrounding brain regions of all distantly related avian vocal learners. This differential expression was specific to PV and vocal learners, as it was not found in avian vocal non-learners nor for control genes in learners and non-learners. Similar to the vocal learning birds, higher PV up-regulation was found in the brainstem tongue motor neurons used for speech production in humans relative to a non-human primate, macaques. These results suggest repeated convergent evolution of differential PV up-regulation in the brains of vocal learners separated by more than 65-300 million years from a common ancestor and that the specialized behaviors of learned song and speech may require extra calcium buffering and signaling.

  19. Nonlocal Quantum Information Transfer Without Superluminal Signalling and Communication

    Science.gov (United States)

    Walleczek, Jan; Grössing, Gerhard

    2016-09-01

    It is a frequent assumption that—via superluminal information transfers—superluminal signals capable of enabling communication are necessarily exchanged in any quantum theory that posits hidden superluminal influences. However, does the presence of hidden superluminal influences automatically imply superluminal signalling and communication? The non-signalling theorem mediates the apparent conflict between quantum mechanics and the theory of special relativity. However, as a `no-go' theorem there exist two opposing interpretations of the non-signalling constraint: foundational and operational. Concerning Bell's theorem, we argue that Bell employed both interpretations, and that he finally adopted the operational position which is associated often with ontological quantum theory, e.g., de Broglie-Bohm theory. This position we refer to as "effective non-signalling". By contrast, associated with orthodox quantum mechanics is the foundational position referred to here as "axiomatic non-signalling". In search of a decisive communication-theoretic criterion for differentiating between "axiomatic" and "effective" non-signalling, we employ the operational framework offered by Shannon's mathematical theory of communication, whereby we distinguish between Shannon signals and non-Shannon signals. We find that an effective non-signalling theorem represents two sub-theorems: (1) Non-transfer-control (NTC) theorem, and (2) Non-signification-control (NSC) theorem. Employing NTC and NSC theorems, we report that effective, instead of axiomatic, non-signalling is entirely sufficient for prohibiting nonlocal communication. Effective non-signalling prevents the instantaneous, i.e., superluminal, transfer of message-encoded information through the controlled use—by a sender-receiver pair —of informationally-correlated detection events, e.g., in EPR-type experiments. An effective non-signalling theorem allows for nonlocal quantum information transfer yet—at the same time

  20. Mice with Dab1 or Vldlr insufficiency exhibit abnormal neonatal vocalization patterns.

    Science.gov (United States)

    Fraley, E R; Burkett, Z D; Day, N F; Schwartz, B A; Phelps, P E; White, S A

    2016-05-17

    Genetic and epigenetic changes in components of the Reelin-signaling pathway (RELN, DAB1) are associated with autism spectrum disorder (ASD) risk. Social communication deficits are a key component of the ASD diagnostic criteria, but the underlying neurogenetic mechanisms remain unknown. Reln insufficient mice exhibit ASD-like behavioral phenotypes including altered neonatal vocalization patterns. Reelin affects multiple pathways including through the receptors, Very low-density lipoprotein receptor (Vldlr), Apolipoprotein receptor 2 (Apoer2), and intracellular signaling molecule Disabled-1 (Dab1). As Vldlr was previously implicated in avian vocalization, here we investigate vocalizations of neonatal mice with a reduction or absence of these components of the Reelin-signaling pathway. Mice with low or no Dab1 expression exhibited reduced calling rates, altered call-type usage, and differential vocal development trajectories. Mice lacking Vldlr expression also had altered call repertoires, and this effect was exacerbated by deficiency in Apoer2. Together with previous findings, these observations 1) solidify a role for Reelin in vocal communication of multiple species, 2) point to the canonical Reelin-signaling pathway as critical for development of normal neonatal calling patterns in mice, and 3) suggest that mutants in this pathway could be used as murine models for Reelin-associated vocal deficits in humans.

  1. Vocally mediated social recognition in anurans

    Science.gov (United States)

    Bee, Mark A.

    2005-09-01

    Anuran amphibians (frogs and toads) are among the most vocal of vertebrates and have long served as model systems for investigating the mechanisms and evolution of acoustic communication. Compared to higher vertebrates, however, the role of cognition in anuran communication has received less attention, at least in part due to the lack of evidence that juvenile anurans learn to produce signals or associate them with particular social contexts. Recent studies of social recognition in two anuran families indicate that territorial male frogs in some species are able to learn about and recognize the individually distinctive properties of the calls of nearby neighbors. For example, male bullfrogs (ranidae) learn about the pitch of a neighbor's vocalizations (an individually distinct voice property) and associate a familiar pitch with the location of the neighbor's territory. As in songbirds, this form of vocally mediated social recognition allows territory holders to direct low levels of aggression toward well-established neighbors, while maintaining a readiness to respond aggressively to more threatening strangers that may attempt a territory takeover. A brief review of currently available data will be used to illustrate how anurans can serve as model systems for investigating the role of cognition in acoustic communication.

  2. Neural FoxP2 and FoxP1 expression in the budgerigar, an avian species with adult vocal learning.

    Science.gov (United States)

    Hara, Erina; Perez, Jemima M; Whitney, Osceola; Chen, Qianqian; White, Stephanie A; Wright, Timothy F

    2015-04-15

    Vocal learning underlies acquisition of both language in humans and vocal signals in some avian taxa. These bird groups and humans exhibit convergent developmental phases and associated brain pathways for vocal communication. The transcription factor FoxP2 plays critical roles in vocal learning in humans and songbirds. Another member of the forkhead box gene family, FoxP1 also shows high expression in brain areas involved in vocal learning and production. Here, we investigate FoxP2 and FoxP1 mRNA and protein in adult male budgerigars (Melopsittacus undulatus), a parrot species that exhibits vocal learning as both juveniles and adults. To examine these molecules in adult vocal learners, we compared their expression patterns in the budgerigar striatal nucleus involved in vocal learning, magnocellular nucleus of the medial striatum (MMSt), across birds with different vocal states, such as vocalizing to a female (directed), vocalizing alone (undirected), and non-vocalizing. We found that both FoxP2 mRNA and protein expressions were consistently lower in MMSt than in the adjacent striatum regardless of the vocal states, whereas previous work has shown that songbirds exhibit down-regulation in the homologous region, Area X, only after singing alone. In contrast, FoxP1 levels were high in MMSt compared to the adjacent striatum in all groups. Taken together these results strengthen the general hypothesis that FoxP2 and FoxP1 have specialized expression in vocal nuclei across a range of taxa, and suggest that the adult vocal plasticity seen in budgerigars may be a product of persistent down-regulation of FoxP2 in MMSt.

  3. All-optical signal processing data communication and storage applications

    CERN Document Server

    Eggleton, Benjamin

    2015-01-01

    This book provides a comprehensive review of the state-of-the art of optical signal processing technologies and devices. It presents breakthrough solutions for enabling a pervasive use of optics in data communication and signal storage applications. It presents presents optical signal processing as solution to overcome the capacity crunch in communication networks. The book content ranges from the development of innovative materials and devices, such as graphene and slow light structures, to the use of nonlinear optics for secure quantum information processing and overcoming the classical Shannon limit on channel capacity and microwave signal processing. Although it holds the promise for a substantial speed improvement, today’s communication infrastructure optics remains largely confined to the signal transport layer, as it lags behind electronics as far as signal processing is concerned. This situation will change in the near future as the tremendous growth of data traffic requires energy efficient and ful...

  4. Signal processing for mobile communications handbook

    CERN Document Server

    Ibnkahla, Mohamed

    2004-01-01

    INTRODUCTIONSignal Processing for Future Mobile Communications Systems: Challenges and Perspectives; Quazi Mehbubar Rahman and Mohamed IbnkahlaCHANNEL MODELING AND ESTIMATIONMultipath Propagation Models for Broadband Wireless Systems; Andreas F. Molisch and Fredrik TufvessonModeling and Estimation of Mobile Channels; Jitendra K. TugnaitMobile Satellite Channels: Statistical Models and Performance Analysis; Giovanni E. Corazza, Alessandro Vanelli-Coralli, Raffaella Pedone, and Massimo NeriMobile Velocity Estimation for Wireless Communications; Bouchra Senadji, Ghazem Azemi, and Boualem Boashash

  5. Exploiting the natural redundancy of chaotic signals in communication systems

    Science.gov (United States)

    Marino; Rosa; Grebogi

    2000-09-18

    Chaotic signals can be used as carriers of information in communication systems. In this work we describe a simple encoding method that allows one to map any desired bit sequence into a chaotic waveform. The redundancy of the resulting information carrying signal enables us to devise a novel signal reconstruction technique that is able to recover relatively large parts of the chaotic signal starting from just a few samples of it. We show that this technique allows one to increase both the transmission reliability and the transmission rate of a communication system even in the presence of noise.

  6. Secure Communication via a Recycling of Attenuated Classical Signals

    Science.gov (United States)

    Smith, A. Matthew

    2017-01-01

    We describe a simple method of interleaving a classical and quantum signal in a secure communication system at a single wavelength. The system transmits data encrypted via a one-time pad on a classical signal and produces a single-photon reflection of the encrypted signal. This attenuated signal can be used to observe eavesdroppers and produce fresh secret bits. The system can be secured against eavesdroppers, detect simple tampering or classical bit errors, produces more secret bits than it consumes, and does not require any entanglement or complex wavelength division multiplexing, thus, making continuous secure two-way communication via one-time pads practical.

  7. Chemical communication: a jewel sheds light on signal evolution.

    Science.gov (United States)

    Lassance, Jean-Marc; Löfstedt, Christer

    2013-05-06

    When others show sexy tails or sing elaborate songs, many animals use the language of chemistry to attract potential mates. A study provides insights into the evolutionary conundrum of how new chemical signals can evolve in an established communication system.

  8. Behavioral ecology, endocrinology and signal reliability of electric communication

    Science.gov (United States)

    Gavassa, Sat; Goldina, Anna; Silva, Ana C.; Stoddard, Philip K.

    2013-01-01

    Summary The balance between the costs and benefits of conspicuous animal communication signals ensures that signal expression relates to the quality of the bearer. Signal plasticity enables males to enhance conspicuous signals to impress mates and competitors and to reduce signal expression to lower energetic and predation-related signaling costs when competition is low. While signal plasticity may benefit the signaler, it can compromise the reliability of the information conveyed by the signals. In this paper we review the effect of signal plasticity on the reliability of the electrocommunication signal of the gymnotiform fish Brachyhypopomus gauderio. We (1) summarize the endocrine regulation of signal plasticity, (2) explore the regulation of signal plasticity in females, (3) examine the information conveyed by the signal, (4) show how that information changes when the signal changes, and (5) consider the energetic strategies used to sustain expensive signaling. The electric organ discharge (EOD) of B. gauderio changes in response to social environment on two time scales. Two hormone classes, melanocortins and androgens, underlie the short-term and long-term modulation of signal amplitude and duration observed during social interaction. Population density drives signal amplitude enhancement, unexpectedly improving the reliability with which the signal predicts the signaler's size. The signal's second phase elongation predicts androgen levels and male reproductive condition. Males sustain signal enhancement with dietary intake, but when food is limited, they ‘go for broke’ and put extra energy into electric signals. Cortisol diminishes EOD parameters, but energy-limited males offset cortisol effects by boosting androgen levels. While physiological constraints are sufficient to maintain signal amplitude reliability, phenotypic integration and signaling costs maintain reliability of signal duration, consistent with theory of honest signaling. PMID:23761465

  9. Processing of Communication Signal Using Operational Transconductance Amplifier

    OpenAIRE

    Roy, A.; Ghosh, K.; Mondal, S; Ray, B. N.

    2010-01-01

    This paper proposes a signal processing methodology of communication system and realized that circuits using operational transconductance amplifier (OTA). Two important classes of communication circuit, delta modulator and compander have been designed using that procedure. In the first implementation coded pulse modulation system is demonstrated which employ sampling, quantizing and coding to convert analog waveforms to digital signals while the second gives data compression and expansion in ...

  10. 4th International Conference on Communications, Signal Processing, and Systems

    CERN Document Server

    Mu, Jiasong; Wang, Wei; Zhang, Baoju

    2016-01-01

    This book brings together papers presented at the 4th International Conference on Communications, Signal Processing, and Systems, which provides a venue to disseminate the latest developments and to discuss the interactions and links between these multidisciplinary fields. Spanning topics ranging from Communications, Signal Processing and Systems, this book is aimed at undergraduate and graduate students in Electrical Engineering, Computer Science and Mathematics, researchers and engineers from academia and industry as well as government employees (such as NSF, DOD, DOE, etc).

  11. Optimal signal patterns for dynamical cellular communication

    CERN Document Server

    Hasegawa, Yoshihiko

    2015-01-01

    Cells transmit information via signaling pathways, using temporal dynamical patterns. As optimality with respect to environments is the universal principle in biological systems, organisms have acquired an optimal way of transmitting information. Here we obtain optimal dynamical signal patterns which can transmit information efficiently (low power) and reliably (high accuracy) using the optimal control theory. Adopting an activation-inactivation decoding network, we reproduced several dynamical patterns found in actual signals, such as steep, gradual and overshooting dynamics. Notably, when minimizing the power of the input signal, optimal signals exhibit the overshooting pattern, which is a biphasic pattern with transient and steady phases; this pattern is prevalent in actual dynamical patterns as it can be generated by an incoherent feed-forward loop (FFL), a common motif in biochemical networks. We also identified conditions when the three patterns, steep, gradual and overshooting, confer advantages.

  12. The Acoustic Properties of Low Intensity Vocalizations Match Hearing Sensitivity in the Webbed-Toed Gecko, Gekko subpalmatus

    Science.gov (United States)

    Chen, Jingfeng; Jono, Teppei; Cui, Jianguo; Yue, Xizi; Tang, Yezhong

    2016-01-01

    The design of acoustic signals and hearing sensitivity in socially communicating species would normally be expected to closely match in order to minimize signal degradation and attenuation during signal propagation. Nevertheless, other factors such as sensory biases as well as morphological and physiological constraints may affect strict correspondence between signal features and hearing sensitivity. Thus study of the relationships between sender and receiver characteristics in species utilizing acoustic communication can provide information about how acoustic communication systems evolve. The genus Gekko includes species emitting high-amplitude vocalizations for long-range communication (loud callers) as well as species producing only low-amplitude vocalizations when in close contact with conspecifics (quiet callers) which have rarely been investigated. In order to investigate relationships between auditory physiology and the frequency characteristics of acoustic signals in a quiet caller, Gekko subpalmatus we measured the subjects’ vocal signal characteristics as well as auditory brainstem responses (ABRs) to assess auditory sensitivity. The results show that G. subpalmatus males emit low amplitude calls when encountering females, ranging in dominant frequency from 2.47 to 4.17 kHz with an average at 3.35 kHz. The auditory range with highest sensitivity closely matches the dominant frequency of the vocalizations. This correspondence is consistent with the notion that quiet and loud calling species are under similar selection pressures for matching auditory sensitivity with spectral characteristics of vocalizations. PMID:26752301

  13. Digital signal processing in communication systems

    CERN Document Server

    Frerking, Marvin E

    1994-01-01

    An engineer's introduction to concepts, algorithms, and advancements in Digital Signal Processing. This lucidly written resource makes extensive use of real-world examples as it covers all the important design and engineering references.

  14. Plasticity in the vocalizations of anurans in response to traffic noise

    Science.gov (United States)

    Cunnington, Glenn M.; Fahrig, Lenore

    2010-09-01

    Many species use acoustic signals to attract mates, and such signals can be degraded by anthropogenic noise. Anuran abundance has been shown to be negatively correlated with road traffic which could be due in part to the interruption of mate attraction by traffic noise. However, this impact could be small if anurans can alter their vocalization characteristics to avoid masking of their calls by traffic noise. We predicted that: (i) anuran vocalization characteristics (dominant frequency, mean amplitude and call rate) should be different in areas with different traffic noise levels; (ii) increases in traffic noise can cause immediate changes in amphibian vocalization characteristics; (iii) these altered vocalizations are similar to those at high traffic sites. To test the first prediction we compared vocalizations of four species of anuran at breeding sites in locations with low traffic noise vs. sites with high traffic noise. For the second prediction we broadcast traffic noise at low traffic (quiet) sites, and compared the anuran vocalizations before vs. during the broadcast traffic noise. For the third prediction we compared vocalizations at high traffic sites to those produced at low traffic sites while broadcasting traffic noise. Three species of anurans found at locations with low traffic noise produced vocalizations with different characteristics than individuals of the same species found in locations with high traffic noise. Broadcast traffic noise immediately altered amphibian vocalization characteristics such that they became similar to those of the same species found in locations with high traffic noise. We conclude that plasticity in the vocalizations of anurans allows for the maintenance of acoustic communication in the presence of traffic noise.

  15. A bond graph approach to modeling the anuran vocal production system.

    Science.gov (United States)

    Kime, Nicole M; Ryan, Michael J; Wilson, Preston S

    2013-06-01

    Air-driven vocal production systems such as those found in mammals, birds, and anurans (frogs and toads) combine pneumatic and mechanical elements in species-specific ways to produce a diversity of communication signals. This study uses bond graphs to model a generalized anuran vocal production system. Bond graphs allow an incremental approach to modeling dynamic physical systems involving different domains. Anurans provide an example of how signal diversity results from variation in the structure and behavior of vocal system elements. This paper first proposes a bond graph model of the integrated anuran vocal system as a framework for future study. It then presents a simulated submodel of the anuran sound source that produces sustained oscillations in vocal fold displacement and air flow through the larynx. The modeling approach illustrated here should prove of general applicability to other biological sound production systems, and will allow researchers to study the biomechanics of vocal production as well as the functional congruence and evolution of groups of traits within integrated vocal systems.

  16. Auditory responses in the amygdala to social vocalizations

    Science.gov (United States)

    Gadziola, Marie A.

    The underlying goal of this dissertation is to understand how the amygdala, a brain region involved in establishing the emotional significance of sensory input, contributes to the processing of complex sounds. The general hypothesis is that communication calls of big brown bats (Eptesicus fuscus) transmit relevant information about social context that is reflected in the activity of amygdalar neurons. The first specific aim analyzed social vocalizations emitted under a variety of behavioral contexts, and related vocalizations to an objective measure of internal physiological state by monitoring the heart rate of vocalizing bats. These experiments revealed a complex acoustic communication system among big brown bats in which acoustic cues and call structure signal the emotional state of a sender. The second specific aim characterized the responsiveness of single neurons in the basolateral amygdala to a range of social syllables. Neurons typically respond to the majority of tested syllables, but effectively discriminate among vocalizations by varying the response duration. This novel coding strategy underscores the importance of persistent firing in the general functioning of the amygdala. The third specific aim examined the influence of acoustic context by characterizing both the behavioral and neurophysiological responses to natural vocal sequences. Vocal sequences differentially modify the internal affective state of a listening bat, with lower aggression vocalizations evoking the greatest change in heart rate. Amygdalar neurons employ two different coding strategies: low background neurons respond selectively to very few stimuli, whereas high background neurons respond broadly to stimuli but demonstrate variation in response magnitude and timing. Neurons appear to discriminate the valence of stimuli, with aggression sequences evoking robust population-level responses across all sound levels. Further, vocal sequences show improved discrimination among stimuli

  17. Signal molecule-mediated hepatic cell communication during liver regeneration

    Institute of Scientific and Technical Information of China (English)

    Zhen-Yu Zheng; Shun-Yan Weng; Yan Yu

    2009-01-01

    Liver regeneration is a complex and well-orchestrated process, during which hepatic cells are activated to produce large signal molecules in response to liver injury or mass reduction. These signal molecules, in turn, set up the connections and cross-talk among liver cells to promote hepatic recovery. In this review, we endeavor to summarize the network of signal molecules that mediates hepatic cell communication in the regulation of liver regeneration.

  18. Evidence for an audience effect in mice: male social partners alter the male vocal response to female cues.

    Science.gov (United States)

    Seagraves, Kelly M; Arthur, Ben J; Egnor, S E Roian

    2016-05-15

    Mice (Mus musculus) form large and dynamic social groups and emit ultrasonic vocalizations in a variety of social contexts. Surprisingly, these vocalizations have been studied almost exclusively in the context of cues from only one social partner, despite the observation that in many social species the presence of additional listeners changes the structure of communication signals. Here, we show that male vocal behavior elicited by female odor is affected by the presence of a male audience - with changes in vocalization count, acoustic structure and syllable complexity. We further show that single sensory cues are not sufficient to elicit this audience effect, indicating that multiple cues may be necessary for an audience to be apparent. Together, these experiments reveal that some features of mouse vocal behavior are only expressed in more complex social situations, and introduce a powerful new assay for measuring detection of the presence of social partners in mice.

  19. Real-time Covert Communications Channel for Audio Signals

    Directory of Open Access Journals (Sweden)

    Ashraf Seleym

    2012-09-01

    Full Text Available Covert communications channel is considered as a type of secure communications that creates capability to transfer information between entities while hiding the contents of the channel. Multimedia data hiding techniques can be used to establish a covert channel for secret communications within a media carrier. In this paper, a high-rate covert communications channel is developed to exploit an audio stream as a carrier signal using multiple embedding in the Quantization Index Modulation framework. The proposed approach uses multi quantization vectors to increase data transmission rate. The embedding algorithms consider the embedding process as a communications problem, that it uses structured scheme of Multiple Trellis-Coded Quantization jointed with Multiple Trellis-Coded Modulation. Using convolution codes based trellis coding returns a real-time communications, because it can be continuously encoded and decoded. The proposed approach exhibits a high channel capacity due to the increase in data embedding rate without severely increasing in embedding distortion.

  20. [Pheromones: an underestimated communication signal in humans].

    Science.gov (United States)

    Frey, J

    2003-01-01

    The pheromones are molecules, mainly aliphatic acids, with or without perceptible odor, recognized by specific receptors, the stimulation of which induces neuroendocrine reactions and affects the individual behavior. Olfactory receptors are underexpressed in human, 70 % of genes have become nonfunctional pseudogenes. But the remaining function was tested and is able to induce emotional reactions corresponding to a non-verbal signal of social interactions. In the present study, we review the actual knowledge on the olfactory receptors. They belong to the G-protein-coupled-receptors. Their signal is transduced to the hypothalamic-pituitary-gonadal axis. Some HLA-based olfactory cues are shown with reference to recent experiments. The pathophysiological hypotheses are considered with respect to studies in anorexia nervosa and Alzheimer' disease.

  1. Impacto vocal de professores Teachers' vocal impact

    Directory of Open Access Journals (Sweden)

    Adriana Ricarte

    2011-08-01

    Full Text Available OBJETIVO: analisar o impacto vocal nas atividades diárias em professores do ensino médio. Correlacionar os achado da auto-percepção do problema vocal com os aspectos: efeitos no trabalho, na comunicação diária, na comunicação social e na sua emoção. MÉTODOS: a amostra foi constituída por 107 professores, sendo 86 com queixa e 21 sem queixa, selecionados em escolas da rede particular de ensino de Maceió-AL. Cada professor respondeu individualmente o protocolo Perfil Participação em Atividades Vocais na presença da pesquisadora, assinalando suas respostas em uma escala visual que varia de 0 a 10. O protocolo é composto por 28 questões com a presença integrada em cinco aspectos englobados para avaliar a qualidade de vida e o resultado de tratamentos vocais. O protocolo oferece, ainda, dois escores adicionais: pontuação de limitação nas atividades (PLA e de restrição de participação (PRP. RESULTADOS: na comparação dos grupos com e sem queixa vocal foram verificados que todos os resultados foram estatisticamente significantes (pPURPOSE: to analyze the vocal impact in the daily activities on high-school teachers. Correlate the finding of the auto-perception on the vocal problem with the following aspects: effects in the work, daily communication, social communication and, its emotion METHODS: the sample consisted of 107 teachers, 86 with and 21 with no complaint, selected from private teaching schools in Maceió-AL. Each teacher answered individually the Protocol for Voice Activity Participation Profile in the presence of the researcher, noting their responses on a visual scale ranging from 0 to 10. The protocol is composed of 28 questions with the presence integrated in five aspects to evaluate the quality of life and the result of vocal treatments. The protocol offers, still, two additional scores: punctuation of limitation in the activities (PLA and restriction of participation (PRP. RESULTS: comparing the groups with

  2. Time reversal signal processing for communication.

    Energy Technology Data Exchange (ETDEWEB)

    Young, Derek P.; Jacklin, Neil; Punnoose, Ratish J.; Counsil, David T.

    2011-09-01

    Time-reversal is a wave focusing technique that makes use of the reciprocity of wireless propagation channels. It works particularly well in a cluttered environment with associated multipath reflection. This technique uses the multipath in the environment to increase focusing ability. Time-reversal can also be used to null signals, either to reduce unintentional interference or to prevent eavesdropping. It does not require controlled geometric placement of the transmit antennas. Unlike existing techniques it can work without line-of-sight. We have explored the performance of time-reversal focusing in a variety of simulated environments. We have also developed new algorithms to simultaneously focus at a location while nulling at an eavesdropper location. We have experimentally verified these techniques in a realistic cluttered environment.

  3. Communication theory and signal processing for transform coding

    CERN Document Server

    El-Shennawy, Khamies Mohammed Ali

    2014-01-01

    This book is tailored to fulfil the requirements in the area of the signal processing in communication systems. The book contains numerous examples, solved problems and exercises to explain the methodology of Fourier Series, Fourier Analysis, Fourier Transform and properties, Fast Fourier Transform FFT, Discrete Fourier Transform DFT and properties, Discrete Cosine Transform DCT, Discrete Wavelet Transform DWT and Contourlet Transform CT. The book is characterized by three directions, the communication theory and signal processing point of view, the mathematical point of view and utility compu

  4. Serial optical communications and ultra-fast optical signal processing of Tbit/s data signals

    DEFF Research Database (Denmark)

    Oxenløwe, Leif Katsuo; Galili, Michael; Hu, Hao;

    2010-01-01

    This paper reviews our recent advances in ultra-high speed serial optical communications. It describes Tbit/s optical signal processing and various materials allowing for this, as well as network scenarios embracing this technology......This paper reviews our recent advances in ultra-high speed serial optical communications. It describes Tbit/s optical signal processing and various materials allowing for this, as well as network scenarios embracing this technology...

  5. Grasshopper mice employ distinct vocal production mechanisms in different social contexts.

    Science.gov (United States)

    Pasch, Bret; Tokuda, Isao T; Riede, Tobias

    2017-07-26

    Functional changes in vocal organ morphology and motor control facilitate the evolution of acoustic signal diversity. Although many rodents produce vocalizations in a variety of social contexts, few studies have explored the underlying production mechanisms. Here, we describe mechanisms of audible and ultrasonic vocalizations (USVs) produced by grasshopper mice (genus Onychomys). Grasshopper mice are predatory rodents of the desert that produce both loud, long-distance advertisement calls and USVs in close-distance mating contexts. Using live-animal recording in normal air and heliox, laryngeal and vocal tract morphological investigations, and biomechanical modelling, we found that grasshopper mice employ two distinct vocal production mechanisms. In heliox, changes in higher-harmonic amplitudes of long-distance calls indicate an airflow-induced tissue vibration mechanism, whereas changes in fundamental frequency of USVs support a whistle mechanism. Vocal membranes and a thin lamina propria aid in the production of long-distance calls by increasing glottal efficiency and permitting high frequencies, respectively. In addition, tuning of fundamental frequency to the second resonance of a bell-shaped vocal tract increases call amplitude. Our findings indicate that grasshopper mice can dynamically adjust motor control to suit the social context and have novel morphological adaptations that facilitate long-distance communication. © 2017 The Author(s).

  6. Indication of a Lombard vocal response in the St. Lawrence River beluga

    Science.gov (United States)

    Scheifele, P. M.; Andrew, S.; Cooper, R. A.; Darre, M.; Musiek, F. E.; Max, L.

    2005-03-01

    Noise pollution is recognized as a potential danger to marine mammals in general, and to the St. Lawrence beluga in particular. One method of determining the impacts of noise on an animal's communication is to observe a natural and repeatable response of the vocal system to variations in noise level. This is accomplished by observing intensity changes in animal vocalizations in response to environmental noise. One such response observed in humans, songbirds, and some primates is the Lombard vocal response. This response represents a vocal system reaction manifested by changes in vocalization level in direct response to changes in the noise field. In this research, a population of belugas in the St. Lawrence River Estuary was tested to determine whether a Lombard response existed by using hidden Markhov-classified vocalizations as targets for acoustical analyses. Correlation and regression analyses of signals and noise indicated that the phenomenon does exist. Further, results of human subjects experiments [Egan, J. J. (1966), Ph.D. dissertation; Scheifele, P. M. (2003), Ph.D. dissertation], along with previously reported data from other animal species, are similar to those exhibited by the belugas. Overall, findings suggest that typical noise levels in the St. Lawrence River Estuary have a detectable effect on the communication of the beluga. .

  7. Development of auditory-vocal perceptual skills in songbirds.

    Directory of Open Access Journals (Sweden)

    Vanessa C Miller-Sims

    Full Text Available Songbirds are one of the few groups of animals that learn the sounds used for vocal communication during development. Like humans, songbirds memorize vocal sounds based on auditory experience with vocalizations of adult "tutors", and then use auditory feedback of self-produced vocalizations to gradually match their motor output to the memory of tutor sounds. In humans, investigations of early vocal learning have focused mainly on perceptual skills of infants, whereas studies of songbirds have focused on measures of vocal production. In order to fully exploit songbirds as a model for human speech, understand the neural basis of learned vocal behavior, and investigate links between vocal perception and production, studies of songbirds must examine both behavioral measures of perception and neural measures of discrimination during development. Here we used behavioral and electrophysiological assays of the ability of songbirds to distinguish vocal calls of varying frequencies at different stages of vocal learning. The results show that neural tuning in auditory cortex mirrors behavioral improvements in the ability to make perceptual distinctions of vocal calls as birds are engaged in vocal learning. Thus, separate measures of neural discrimination and behavioral perception yielded highly similar trends during the course of vocal development. The timing of this improvement in the ability to distinguish vocal sounds correlates with our previous work showing substantial refinement of axonal connectivity in cortico-basal ganglia pathways necessary for vocal learning.

  8. Development of auditory-vocal perceptual skills in songbirds.

    Science.gov (United States)

    Miller-Sims, Vanessa C; Bottjer, Sarah W

    2012-01-01

    Songbirds are one of the few groups of animals that learn the sounds used for vocal communication during development. Like humans, songbirds memorize vocal sounds based on auditory experience with vocalizations of adult "tutors", and then use auditory feedback of self-produced vocalizations to gradually match their motor output to the memory of tutor sounds. In humans, investigations of early vocal learning have focused mainly on perceptual skills of infants, whereas studies of songbirds have focused on measures of vocal production. In order to fully exploit songbirds as a model for human speech, understand the neural basis of learned vocal behavior, and investigate links between vocal perception and production, studies of songbirds must examine both behavioral measures of perception and neural measures of discrimination during development. Here we used behavioral and electrophysiological assays of the ability of songbirds to distinguish vocal calls of varying frequencies at different stages of vocal learning. The results show that neural tuning in auditory cortex mirrors behavioral improvements in the ability to make perceptual distinctions of vocal calls as birds are engaged in vocal learning. Thus, separate measures of neural discrimination and behavioral perception yielded highly similar trends during the course of vocal development. The timing of this improvement in the ability to distinguish vocal sounds correlates with our previous work showing substantial refinement of axonal connectivity in cortico-basal ganglia pathways necessary for vocal learning.

  9. Space-Time Coding and Signal Processing for MIMO Communications

    Institute of Scientific and Technical Information of China (English)

    Inaki Berenguer; Xiaodong Wang

    2003-01-01

    Rapid growth in mobile computing and other wireless multimedia services is inspiring many research and development activities on high-speed wireless communication systems.Main challenges in this area include the development of efficient coding and modulation signal processing techniques for improving the quality and spectral efficiency of wireless systems. The recently emerged space-time coding and signal processing techniques for wireless communication systems employing multiple transmit and receive antennas offer a powerful paradigm for meeting these challenges. This paper provides an overview on the recent development in space-time coding and signal processing techniques for multiple-input multiple-output (MIMO) communication systems. We first review the information theoretic results on the capacities of wireless systems employing multiple transmit and receive antennas. We then describe two representative categories of space-time systems, namely, the BLAST system and the space-time block coding system, both of which have been proposed for next-generation high-speed wireless system. Signal processing techniques for channel estimation and decoding in space-time systems are also discussed. Finally, some other coding and signal processing techniques for wireless systems employing multiple transmit and receive antennas that are currently under intensive research are also briefly touched upon.

  10. Central pattern generator for vocalization: is there a vertebrate morphotype?

    Science.gov (United States)

    Bass, Andrew H

    2014-10-01

    Animals that generate acoustic signals for social communication are faced with two essential tasks: generate a temporally precise signal and inform the auditory system about the occurrence of one's own sonic signal. Recent studies of sound producing fishes delineate a hindbrain network comprised of anatomically distinct compartments coding equally distinct neurophysiological properties that allow an organism to meet these behavioral demands. A set of neural characters comprising a vocal-sonic central pattern generator (CPG) morphotype is proposed for fishes and tetrapods that shares evolutionary developmental origins with pectoral appendage motor systems.

  11. Digital signal processing for wireless communication using Matlab

    CERN Document Server

    Gopi, E S

    2016-01-01

    This book examines signal processing techniques used in wireless communication illustrated by using the Matlab program. The author discusses these techniques as they relate to Doppler spread; delay spread; Rayleigh and Rician channel modeling; rake receiver; diversity techniques; MIMO and OFDM -based transmission techniques; and array signal processing. Related topics such as detection theory, link budget, multiple access techniques, and spread spectrum are also covered.   ·         Illustrates signal processing techniques involved in wireless communication using Matlab ·         Discusses multiple access techniques such as Frequency division multiple access, Time division multiple access, and Code division multiple access ·         Covers band pass modulation techniques such as Binary phase shift keying, Differential phase shift keying, Quadrature phase shift keying, Binary frequency shift keying, Minimum shift keying, and Gaussian minimum shift keying.

  12. Critique du rapport signal \\`a bruit en communications num\\'eriques -- Questioning the signal to noise ratio in digital communications

    CERN Document Server

    Fliess, Michel

    2008-01-01

    The signal to noise ratio, which plays such an important r\\^ole in information theory, is shown to become pointless for digital communications where the demodulation is achieved via new fast estimation techniques. Operational calculus, differential algebra, noncommutative algebra and nonstandard analysis are the main mathematical tools.

  13. All-optical signal processing technique for secure optical communication

    Science.gov (United States)

    Qian, Feng-chen; Su, Bing; Ye, Ya-lin; Zhang, Qian; Lin, Shao-feng; Duan, Tao; Duan, Jie

    2015-10-01

    Secure optical communication technologies are important means to solve the physical layer security for optical network. We present a scheme of secure optical communication system by all-optical signal processing technique. The scheme consists of three parts, as all-optical signal processing unit, optical key sequence generator, and synchronous control unit. In the paper, all-optical signal processing method is key technology using all-optical exclusive disjunction (XOR) gate based on optical cross-gain modulation effect, has advantages of wide dynamic range of input optical signal, simple structure and so on. All-optical XOR gate composed of two semiconductor optical amplifiers (SOA) is a symmetrical structure. By controlling injection current, input signal power, delay and filter bandwidth, the extinction ratio of XOR can be greater than 8dB. Finally, some performance parameters are calculated and the results are analyzed. The simulation and experimental results show that the proposed method can be achieved over 10Gbps optical signal encryption and decryption, which is simple, easy to implement, and error-free diffusion.

  14. Organelle communication: signaling crossroads between homeostasis and disease.

    Science.gov (United States)

    Bravo-Sagua, Roberto; Torrealba, Natalia; Paredes, Felipe; Morales, Pablo E; Pennanen, Christian; López-Crisosto, Camila; Troncoso, Rodrigo; Criollo, Alfredo; Chiong, Mario; Hill, Joseph A; Simmen, Thomas; Quest, Andrew F; Lavandero, Sergio

    2014-05-01

    Cellular organelles do not function as isolated or static units, but rather form dynamic contacts between one another that can be modulated according to cellular needs. The physical interfaces between organelles are important for Ca2+ and lipid homeostasis, and serve as platforms for the control of many essential functions including metabolism, signaling, organelle integrity and execution of the apoptotic program. Emerging evidence also highlights the importance of organelle communication in disorders such as Alzheimer's disease, pulmonary arterial hypertension, cancer, skeletal and cardiac muscle dysfunction. Here, we provide an overview of the current literature on organelle communication and the link to human pathologies. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Reinforcement of vocalizations through contingent vocal imitation.

    Science.gov (United States)

    Pelaez, Martha; Virues-Ortega, Javier; Gewirtz, Jacob L

    2011-01-01

    Maternal vocal imitation of infant vocalizations is highly prevalent during face-to-face interactions of infants and their caregivers. Although maternal vocal imitation has been associated with later verbal development, its potentially reinforcing effect on infant vocalizations has not been explored experimentally. This study examined the reinforcing effect of maternal vocal imitation of infant vocalizations using a reversal probe BAB design. Eleven 3- to 8-month-old infants at high risk for developmental delays experienced contingent maternal vocal imitation during reinforcement conditions. Differential reinforcement of other behavior served as the control condition. The behavior of 10 infants showed evidence of a reinforcement effect. Results indicated that vocal imitations can serve to reinforce early infant vocalizations.

  16. Time Reversal Signal Processing in Communications - A Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, A W; Candy, J V; Poggio, A J

    2002-01-30

    A typical communications channel is subjected to a variety of signal distortions, including multipath, that corrupt the information being transmitted and reduce the effective channel capacity. The mitigation of the multipath interference component is an ongoing concern for communication systems operating in complex environments such as might be experienced inside buildings, urban environments, and hilly or heavily wooded areas. Communications between mobile units and distributed sensors, so important to national security, are dependent upon flawless conveyance of information in complex environments. The reduction of this multipath corruption necessitates better channel equalization, i.e., the removal of channel distortion to extract the transmitted information. But, the current state of the art in channel equalization either requires a priori knowledge of the channel or the use of a known training sequence and adaptive filtering. If the ''assumed'' model within the equalization processor does not at least capture the dominant characteristics of the channel, then the received information may still be highly distorted and possibly useless. Also, the processing required for classical equalization is demanding in computational resources. To remedy this situation, many techniques have been investigated to replace classical equalization. Such a technique, the subject of this feasibility study, is Time Reversal Signal Processing (TRSP). Multipath is particularly insidious and a major factor in the deterioration of communication channels. Unlike most other characteristics that corrupt a communications channel, the detrimental effects of multipath cannot be overcome by merely increasing the transmitted power. Although the power in a signal diminishes as a function of the distance between the transmitter and receiver, multipath further degrades a signal by creating destructive interference that results in a loss of received power in a very localized area

  17. Signal Conditioning An Introduction to Continuous Wave Communication and Signal Processing

    CERN Document Server

    Das, Apurba

    2012-01-01

    "Signal Conditioning” is a comprehensive introduction to electronic signal processing. The book presents the mathematical basics including the implications of various transformed domain representations in signal synthesis and analysis in an understandable and lucid fashion and illustrates the theory through many applications and examples from communication systems. The ease to learn is supported by well-chosen exercises which give readers the flavor of the subject. Supplementary electronic materials available on http://extras.springer.com including MATLAB codes illuminating applications in the domain of one dimensional electrical signal processing, image processing and speech processing. The book is an introduction for students with a basic understanding in engineering or natural sciences.

  18. Timing and time signal distribution in digital communications networks

    Science.gov (United States)

    Kihara, Masami; Imaoka, Atushi

    1992-06-01

    The timing signal distribution characteristics of a digital communications network are evaluated to determine the Maximum Time Interval Error (MTIE) of the network; reference is made to the performance of network components such as transmission systems, slave clocks and timing distribution systems in intraoffices. The MTIE of each component is measured and used to determine the allowable MTIE of that component. The maximum number of slave node chains is shown to be 20. Time signal distribution performance is detailed. It is shown that time synchronization accuracy is of the order of submicroseconds between nodes separated by 2400 km over a two year period. For intra-office time signal distribution, the relative time accuracy is less than 3 nanoseconds using an 8 Mb/s round trip digital interface to connect a time signal supply in an office to dispersed equipment.

  19. Phylogeny of the lemuridae revisited: evidence from communication signals.

    Science.gov (United States)

    Macedonia, J M; Stanger, K F

    1994-01-01

    Phylogenetic relationships among the extant lemurid prosimians were assessed cladistically using stereotyped vocal, olfactory, and visual communication characters. Among our results are 3 findings of particular importance. First, our data are consistent with those from several recent studies of highly repeated DNA fragments in supporting a close phyletic affinity between Lemur catta and the genus Hapalemur. Moreover, our results indicate that L. catta is nested within the Hapalemur clade as the sister taxon to Hapalemur griseus/Hapalemur aureus. We interpret character states shared between Hapalemur simus and L. catta as primitive retentions by L. catta. Second, our findings agree with the DNA data in proposing a sister group relationship for Eulemur coronatus and Eulemur rubriventer. Third, our results question the validity of assigning Varecia variegata to the Lemuridae. For the characters we examined, Varecia more resembled indrids than lemurids, and the position of Varecia could be swapped with any of our outgroups (Indri, Propithecus, Daubentonia) without affecting tree topology. Previous workers sometimes have linked Varecia with various lemurids on grounds of ambiguously defined characters or on incorrect data gleaned from the literature. In those studies, the placement of Varecia in the Lemuridae usually has depended more on the minimization of character state conflicts (i.e. parsimony), than on demonstrable synapomorphies. In addition, data from DNA research have failed to demonstrate any pattern that links Varecia with Lemur, Hapalemur, or Eulemur. Results of the present study suggest that shared Varecia-indrid character states may be symplesiomorphic retentions in the Indridae, and that Varecia could be phyletically more primitive than either the indrids or lemurids.

  20. Flash signal evolution in Photinus fireflies: character displacement and signal exploitation in a visual communication system.

    Science.gov (United States)

    Stanger-Hall, Kathrin F; Lloyd, James E

    2015-03-01

    Animal communication is an intriguing topic in evolutionary biology. In this comprehensive study of visual signal evolution, we used a phylogenetic approach to study the evolution of the flash communication system of North American fireflies. The North American firefly genus Photinus contains 35 described species with simple ON-OFF visual signals, and information on habitat types, sympatric congeners, and predators. This makes them an ideal study system to test hypotheses on the evolution of male and female visual signal traits. Our analysis of 34 Photinus species suggests two temporal pattern generators: one for flash duration and one for flash intervals. Reproductive character displacement was a main factor for signal divergence in male flash duration among sympatric Photinus species. Male flash pattern intervals (i.e., the duration of the dark periods between signals) were positively correlated with the number of sympatric Photuris fireflies, which include predators of Photinus. Females of different Photinus species differ in their response preferences to male traits. As in other communication systems, firefly male sexual signals seem to be a compromise between optimizing mating success (sexual selection) and minimizing predation risk (natural selection). An integrative model for Photinus signal evolution is proposed.

  1. Explaining evolution of plant communication by airborne signals.

    Science.gov (United States)

    Heil, Martin; Karban, Richard

    2010-03-01

    In spite of initial doubts about the reality of 'talking trees', plant resistance expression mediated by volatile compounds that come from neighboring plants is now well described. Airborne signals usually improve the resistance of the receiver, but without obvious benefits for the emitter, thus making the evolutionary explanation of this phenomenon problematic. Here, we discuss four possible non-exclusive explanations involving the role of volatiles: in direct defense, as within-plant signals, as traits that synergistically interact with other defenses, and as cues among kin. Unfortunately, there is a lack of knowledge on the fitness consequences of plant communication for both emitter and receiver. This information is crucial to understanding the ecology and evolution of plant communication via airborne cues.

  2. Digital Signal Processing for Optical Coherent Communication Systems

    DEFF Research Database (Denmark)

    Zhang, Xu

    In this thesis, digital signal processing (DSP) algorithms are studied to compensate for physical layer impairments in optical fiber coherent communication systems. The physical layer impairments investigated in this thesis include optical fiber chromatic dispersion, polarization demultiplexing......, light sources frequency and phase offset and phase noise. The studied DSP algorithms are considered as key building blocks in digital coherent receivers for the next generation of optical communication systems such as 112-Gb/s dual polarization (DP) quadrature phase shift keying (QPSK) optical...... spectrum narrowing tolerance 112-Gb/s DP-QPSK optical coherent systems using digital adaptive equalizer. The demonstrated results show that off-line DSP algorithms are able to reduce the bit error rate (BER) penalty induced by signal spectrum narrowing. Third, we also investigate bi...

  3. Acoustic allometry revisited: morphological determinants of fundamental frequency in primate vocal production.

    Science.gov (United States)

    Garcia, Maxime; Herbst, Christian T; Bowling, Daniel L; Dunn, Jacob C; Fitch, W Tecumseh

    2017-09-05

    A fundamental issue in the evolution of communication is the degree to which signals convey accurate ("honest") information about the signaler. In bioacoustics, the assumption that fundamental frequency (f o) should correlate with the body size of the caller is widespread, but this belief has been challenged by various studies, possibly because larynx size and body size can vary independently. In the present comparative study, we conducted excised larynx experiments to investigate this hypothesis rigorously and explore the determinants of f o. Using specimens from eleven primate species, we carried out an inter-specific investigation, examining correlations between the minimum f o produced by the sound source, body size and vocal fold length (VFL). We found that, across species, VFL predicted minimum f o much better than body size, clearly demonstrating the potential for decoupling between larynx size and body size in primates. These findings shed new light on the diversity of primate vocalizations and vocal morphology, highlighting the importance of vocal physiology in understanding the evolution of mammal vocal communication.

  4. Can vocal conditioning trigger a semiotic ratchet in marmosets?

    Science.gov (United States)

    Turesson, Hjalmar K; Ribeiro, Sidarta

    2015-01-01

    The complexity of human communication has often been taken as evidence that our language reflects a true evolutionary leap, bearing little resemblance to any other animal communication system. The putative uniqueness of the human language poses serious evolutionary and ethological challenges to a rational explanation of human communication. Here we review ethological, anatomical, molecular, and computational results across several species to set boundaries for these challenges. Results from animal behavior, cognitive psychology, neurobiology, and semiotics indicate that human language shares multiple features with other primate communication systems, such as specialized brain circuits for sensorimotor processing, the capability for indexical (pointing) and symbolic (referential) signaling, the importance of shared intentionality for associative learning, affective conditioning and parental scaffolding of vocal production. The most substantial differences lie in the higher human capacity for symbolic compositionality, fast vertical transmission of new symbols across generations, and irreversible accumulation of novel adaptive behaviors (cultural ratchet). We hypothesize that increasingly-complex vocal conditioning of an appropriate animal model may be sufficient to trigger a semiotic ratchet, evidenced by progressive sign complexification, as spontaneous contact calls become indexes, then symbols and finally arguments (strings of symbols). To test this hypothesis, we outline a series of conditioning experiments in the common marmoset (Callithrix jacchus). The experiments are designed to probe the limits of vocal communication in a prosocial, highly vocal primate 35 million years far from the human lineage, so as to shed light on the mechanisms of semiotic complexification and cultural transmission, and serve as a naturalistic behavioral setting for the investigation of language disorders.

  5. Can vocal conditioning trigger a semiotic ratchet in marmosets?

    Directory of Open Access Journals (Sweden)

    Hjalmar Kosmos Turesson

    2015-10-01

    Full Text Available The complexity of human communication has often been taken as evidence that our language reflects a true evolutionary leap, bearing little resemblance to any other animal communication system. The putative uniqueness of the human language poses serious evolutionary and ethological challenges to a rational explanation of human communication. Here we review ethological, anatomical, molecular and computational results across several species to set boundaries for these challenges. Results from animal behavior, cognitive psychology, neurobiology, and semiotics indicate that human language shares multiple features with other primate communication systems, such as specialized brain circuits for sensorimotor processing, the capability for indexical (pointing and symbolic (referential signaling, the importance of shared intentionality for associative learning, affective conditioning and parental scaffolding of vocal production. The most substantial differences lie in the higher human capacity for symbolic compositionality, fast vertical transmission of new symbols across generations, and irreversible accumulation of novel adaptive behaviors (cultural ratchet. We hypothesize that increasingly-complex vocal conditioning of an appropriate animal model may be sufficient to trigger a semiotic ratchet, evidenced by progressive sign complexification, as spontaneous contact calls become indexes, then symbols and finally arguments (strings of symbols. To test this hypothesis, we outline a series of conditioning experiments in the common marmoset (Callithrix jacchus. The experiments are designed to probe the limits of vocal communication in a prosocial, highly vocal primate 35 million years far from the human lineage, so as to shed light on the mechanisms of semiotic complexification and cultural transmission, and serve as a naturalistic behavioral setting for the investigation of language disorders.

  6. Auditory–vocal mirroring in songbirds

    Science.gov (United States)

    Mooney, Richard

    2014-01-01

    Mirror neurons are theorized to serve as a neural substrate for spoken language in humans, but the existence and functions of auditory–vocal mirror neurons in the human brain remain largely matters of speculation. Songbirds resemble humans in their capacity for vocal learning and depend on their learned songs to facilitate courtship and individual recognition. Recent neurophysiological studies have detected putative auditory–vocal mirror neurons in a sensorimotor region of the songbird's brain that plays an important role in expressive and receptive aspects of vocal communication. This review discusses the auditory and motor-related properties of these cells, considers their potential role on song learning and communication in relation to classical studies of birdsong, and points to the circuit and developmental mechanisms that may give rise to auditory–vocal mirroring in the songbird's brain. PMID:24778375

  7. Multiplexed temporal coding of electric communication signals in mormyrid fishes.

    Science.gov (United States)

    Baker, Christa A; Kohashi, Tsunehiko; Lyons-Warren, Ariel M; Ma, Xiaofeng; Carlson, Bruce A

    2013-07-01

    The coding of stimulus information into patterns of spike times occurs widely in sensory systems. Determining how temporally coded information is decoded by central neurons is essential to understanding how brains process sensory stimuli. Mormyrid weakly electric fishes are experts at time coding, making them an exemplary organism for addressing this question. Mormyrids generate brief, stereotyped electric pulses. Pulse waveform carries information about sender identity, and it is encoded into submillisecond-to-millisecond differences in spike timing between receptors. Mormyrids vary the time between pulses to communicate behavioral state, and these intervals are encoded into the sequence of interspike intervals within receptors. Thus, the responses of peripheral electroreceptors establish a temporally multiplexed code for communication signals, one consisting of spike timing differences between receptors and a second consisting of interspike intervals within receptors. These signals are processed in a dedicated sensory pathway, and recent studies have shed light on the mechanisms by which central circuits can extract behaviorally relevant information from multiplexed temporal codes. Evolutionary change in the anatomy of this pathway is related to differences in electrosensory perception, which appears to have influenced the diversification of electric signals and species. However, it remains unknown how this evolutionary change relates to differences in sensory coding schemes, neuronal circuitry and central sensory processing. The mormyrid electric communication pathway is a powerful model for integrating mechanistic studies of temporal coding with evolutionary studies of correlated differences in brain and behavior to investigate neural mechanisms for processing temporal codes.

  8. Ultrasonic vocalizations emitted by flying squirrels.

    Directory of Open Access Journals (Sweden)

    Meghan N Murrant

    Full Text Available Anecdotal reports of ultrasound use by flying squirrels have existed for decades, yet there has been little detailed analysis of their vocalizations. Here we demonstrate that two species of flying squirrel emit ultrasonic vocalizations. We recorded vocalizations from northern (Glaucomys sabrinus and southern (G. volans flying squirrels calling in both the laboratory and at a field site in central Ontario, Canada. We demonstrate that flying squirrels produce ultrasonic emissions through recorded bursts of broadband noise and time-frequency structured frequency modulated (FM vocalizations, some of which were purely ultrasonic. Squirrels emitted three types of ultrasonic calls in laboratory recordings and one type in the field. The variety of signals that were recorded suggest that flying squirrels may use ultrasonic vocalizations to transfer information. Thus, vocalizations may be an important, although still poorly understood, aspect of flying squirrel social biology.

  9. Animal vocal sequences: not the Markov chains we thought they were.

    Science.gov (United States)

    Kershenbaum, Arik; Bowles, Ann E; Freeberg, Todd M; Jin, Dezhe Z; Lameira, Adriano R; Bohn, Kirsten

    2014-10-07

    Many animals produce vocal sequences that appear complex. Most researchers assume that these sequences are well characterized as Markov chains (i.e. that the probability of a particular vocal element can be calculated from the history of only a finite number of preceding elements). However, this assumption has never been explicitly tested. Furthermore, it is unclear how language could evolve in a single step from a Markovian origin, as is frequently assumed, as no intermediate forms have been found between animal communication and human language. Here, we assess whether animal taxa produce vocal sequences that are better described by Markov chains, or by non-Markovian dynamics such as the 'renewal process' (RP), characterized by a strong tendency to repeat elements. We examined vocal sequences of seven taxa: Bengalese finches Lonchura striata domestica, Carolina chickadees Poecile carolinensis, free-tailed bats Tadarida brasiliensis, rock hyraxes Procavia capensis, pilot whales Globicephala macrorhynchus, killer whales Orcinus orca and orangutans Pongo spp. The vocal systems of most of these species are more consistent with a non-Markovian RP than with the Markovian models traditionally assumed. Our data suggest that non-Markovian vocal sequences may be more common than Markov sequences, which must be taken into account when evaluating alternative hypotheses for the evolution of signalling complexity, and perhaps human language origins.

  10. Processing emotions in sounds: cross-domain aftereffects of vocal utterances and musical sounds.

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    Bowman, Casady; Yamauchi, Takashi

    2016-11-16

    Nonlinguistic signals in the voice and musical instruments play a critical role in communicating emotion. Although previous research suggests a common mechanism for emotion processing in music and speech, the precise relationship between the two domains is unclear due to the paucity of direct evidence. By applying the adaptation paradigm developed by Bestelmeyer, Rouger, DeBruine, and Belin [2010. Auditory adaptation in vocal affect perception. Cognition, 117(2), 217-223. doi: 10.1016/j.cognition.2010.08.008 ], this study shows cross-domain aftereffects from vocal to musical sounds. Participants heard an angry or fearful sound four times, followed by a test sound and judged whether the test sound was angry or fearful. Results show cross-domain aftereffects in one direction - vocal utterances to musical sounds, not vice-versa. This effect occurred primarily for angry vocal sounds. It is argued that there is a unidirectional relationship between vocal and musical sounds where emotion processing of vocal sounds encompasses musical sounds but not vice-versa.

  11. Vocal Interactivity in-and-between Humans, Animals and Robots

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    Roger K Moore

    2016-10-01

    Full Text Available Almost all animals exploit vocal signals for a range of ecologically-motivated purposes: detecting predators prey and marking territory, expressing emotions, establishing social relations and sharing information. Whether it is a bird raising an alarm, a whale calling to potential partners,a dog responding to human commands, a parent reading a story with a child, or a business-person accessing stock prices using emph{Siri}, vocalisation provides a valuable communication channel through which behaviour may be coordinated and controlled, and information may be distributed and acquired.Indeed, the ubiquity of vocal interaction has led to research across an extremely diverse array of fields, from assessing animal welfare, to understanding the precursors of human language, to developing voice-based human-machine interaction. Opportunities for cross-fertilisation between these fields abound; for example, using artificial cognitive agents to investigate contemporary theories of language grounding, using machine learning to analyse different habitats or adding vocal expressivity to the next generation of language-enabled autonomous social agents. However, much of the research is conducted within well-defined disciplinary boundaries, and many fundamental issues remain. This paper attempts to redress the balance by presenting a comparative review of vocal interaction within-and-between humans, animals and artificial agents (such as robots, and it identifies a rich set of open research questions that may benefit from an inter-disciplinary analysis.

  12. Circularly Polarized Light as a Communication Signal in Mantis Shrimps.

    Science.gov (United States)

    Gagnon, Yakir Luc; Templin, Rachel Marie; How, Martin John; Marshall, N Justin

    2015-12-07

    Animals that communicate using conspicuous body patterns face a trade-off between desired detection by intended receivers and undesired detection from eavesdropping predators, prey, rivals, or parasites. In some cases, this trade-off favors the evolution of signals that are both hidden from predators and visible to conspecifics. Animals may produce covert signals using a property of light that is invisible to those that they wish to evade, allowing them to hide in plain sight (e.g., dragonfish can see their own, otherwise rare, red bioluminescence). The use of the polarization of light is a good example of a potentially covert communication channel, as very few vertebrates are known to use polarization for object-based vision. However, even these patterns are vulnerable to eavesdroppers, as sensitivity to the linearly polarized component of light is widespread among invertebrates due to their intrinsically polarization sensitive photoreceptors. Stomatopod crustaceans appear to have gone one step further in this arms race and have evolved a sensitivity to the circular polarization of light, along with body patterns producing it. However, to date we have no direct evidence that any of these marine crustaceans use this modality to communicate with conspecifics. We therefore investigated circular polarization vision of the mantis shrimp Gonodactylaceus falcatus and demonstrate that (1) the species produces strongly circularly polarized body patterns, (2) they discriminate the circular polarization of light, and (3) that they use circular polarization information to avoid occupied burrows when seeking a refuge. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Animal communication.

    Science.gov (United States)

    Kaplan, Gisela

    2014-11-01

    Animal communication is first and foremost about signal transmission and aims to understand how communication occurs. It is a field that has contributed to and been inspired by other fields, from information technology to neuroscience, in finding ever better methods to eavesdrop on the actual 'message' that forms the basis of communication. Much of this review deals with vocal communication as an example of the questions that research on communication has tried to answer and it provides an historical overview of the theoretical arguments proposed. Topics covered include signal transmission in different environments and different species, referential signaling, and intentionality. The contention is that animal communication may reveal significant thought processes that enable some individuals in a small number of species so far investigated to anticipate what conspecifics might do, although some researchers think of such behavior as adaptive or worth dismissing as anthropomorphizing. The review further points out that some species are more likely than others to develop more complex communication patterns. It is a matter of asking how animals categorize their world and which concepts require cognitive processes and which are adaptive. The review concludes with questions of life history, social learning, and decision making, all criteria that have remained relatively unexplored in communication research. Long-lived, cooperative social animals have so far offered especially exciting prospects for investigation. There are ample opportunities and now very advanced technologies as well to tap further into expressions of memory of signals, be they vocal or expressed in other modalities. WIREs Cogn Sci 2014, 5:661-677. doi: 10.1002/wcs.1321 For further resources related to this article, please visit the WIREs website. The author has declared no conflicts of interest for this article. © 2014 John Wiley & Sons, Ltd.

  14. The vocal monotony of monogamy

    Science.gov (United States)

    Thomas, Jeanette

    2003-04-01

    There are four phocids in waters around Antarctica: Weddell, leopard, crabeater, and Ross seals. These four species provide a unique opportunity to examine underwater vocal behavior in species sharing the same ecosystem. Some species live in pack ice, others in factice, but all are restricted to the Antarctic or sub-Antarctic islands. All breed and produce vocalizations under water. Social systems range from polygyny in large breeding colonies, to serial monogamy, to solitary species. The type of mating system influences the number of underwater vocalizations in the repertoire, with monogamous seals producing only a single call, polygynous species producing up to 35 calls, and solitary species an intermediate number of about 10 calls. Breeding occurs during the austral spring and each species carves-out an acoustic niche for communicating, with species using different frequency ranges, temporal patterns, and amplitude changes to convey their species-specific calls and presumably reduce acoustic competition. Some species exhibit geographic variations in their vocalizations around the continent, which may reflect discrete breeding populations. Some seals become silent during a vulnerable time of predation by killer whales, perhaps to avoid detection. Overall, vocalizations of these seals exhibit adaptive characteristics that reflect the co-evolution among species in the same ecosystem.

  15. A cervid vocal fold model suggests greater glottal efficiency in calling at high frequencies.

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    Ingo R Titze

    Full Text Available Male Rocky Mountain elk (Cervus elaphus nelsoni produce loud and high fundamental frequency bugles during the mating season, in contrast to the male European Red Deer (Cervus elaphus scoticus who produces loud and low fundamental frequency roaring calls. A critical step in understanding vocal communication is to relate sound complexity to anatomy and physiology in a causal manner. Experimentation at the sound source, often difficult in vivo in mammals, is simulated here by a finite element model of the larynx and a wave propagation model of the vocal tract, both based on the morphology and biomechanics of the elk. The model can produce a wide range of fundamental frequencies. Low fundamental frequencies require low vocal fold strain, but large lung pressure and large glottal flow if sound intensity level is to exceed 70 dB at 10 m distance. A high-frequency bugle requires both large muscular effort (to strain the vocal ligament and high lung pressure (to overcome phonation threshold pressure, but at least 10 dB more intensity level can be achieved. Glottal efficiency, the ration of radiated sound power to aerodynamic power at the glottis, is higher in elk, suggesting an advantage of high-pitched signaling. This advantage is based on two aspects; first, the lower airflow required for aerodynamic power and, second, an acoustic radiation advantage at higher frequencies. Both signal types are used by the respective males during the mating season and probably serve as honest signals. The two signal types relate differently to physical qualities of the sender. The low-frequency sound (Red Deer call relates to overall body size via a strong relationship between acoustic parameters and the size of vocal organs and body size. The high-frequency bugle may signal muscular strength and endurance, via a 'vocalizing at the edge' mechanism, for which efficiency is critical.

  16. 2012 Proceedings of the International Conference on Communications, Signal Processing, and Systems

    CERN Document Server

    Wang, Wei; Mu, Jiasong; Liang, Jing; Zhang, Baoju; Pi, Yiming; Zhao, Chenglin

    2012-01-01

    Communications, Signal Processing, and Systems is a collection of contributions coming out of the International Conference on Communications, Signal Processing, and Systems (CSPS) held October 2012. This book provides the state-of-art developments of Communications, Signal Processing, and Systems, and their interactions in multidisciplinary fields, such as Smart Grid. The book also examines Radar Systems, Sensor Networks, Radar Signal Processing, Design and Implementation of Signal Processing Systems and Applications. Written by experts and students in the fields of Communications, Signal Processing, and Systems.

  17. Sonic hedgehog signaling in kidney fibrosis: a master communicator.

    Science.gov (United States)

    Zhou, Dong; Tan, Roderick J; Liu, Youhua

    2016-09-01

    The hedgehog signaling cascade is an evolutionarily conserved pathway that regulates multiple aspects of embryonic development and plays a decisive role in tissue homeostasis. As the best studied member of three hedgehog ligands, sonic hedgehog (Shh) is known to be associated with kidney development and tissue repair after various insults. Recent studies uncover an intrinsic link between dysregulated Shh signaling and renal fibrogenesis. In various types of chronic kidney disease (CKD), Shh is upregulated specifically in renal tubular epithelium but targets interstitial fibroblasts, thereby mediating a dynamic epithelial- mesenchymal communication (EMC). Tubule-derived Shh acts as a growth factor for interstitial fibroblasts and controls a hierarchy of fibrosis-related genes, which lead to the excessive deposition of extracellular matrix in renal interstitium. In this review, we recapitulate the principle of Shh signaling, its activation and regulation in a variety of kidney diseases. We also discuss the potential mechanisms by which Shh promotes renal fibrosis and assess the efficacy of blocking this signaling in preclinical settings. Continuing these lines of investigations will provide novel opportunities for designing effective therapies to improve CKD prognosis in patients.

  18. Effect of Ionosphere on Geostationary Communication Satellite Signals

    Science.gov (United States)

    Erdem, Esra; Arikan, Feza; Gulgonul, Senol

    2016-07-01

    Geostationary orbit (GEO) communications satellites allow radio, television, and telephone transmissions to be sent live anywhere in the world. They are extremely important in daily life and also for military applications. Since, satellite communication is an expensive technology addressing crowd of people, it is critical to improve the performance of this technology. GEO satellites are at 35,786 kilometres from Earth's surface situated directly over the equator. A satellite in a geostationary orbit (GEO) appears to stand still in the sky, in a fixed position with respect to an observer on the earth, because the satellite's orbital period is the same as the rotation rate of the Earth. The advantage of this orbit is that ground antennas can be fixed to point towards to satellite without their having to track the satellite's motion. Radio frequency ranges used in satellite communications are C, X, Ku, Ka and even EHG and V-band. Satellite signals are disturbed by atmospheric effects on the path between the satellite and the receiver antenna. These effects are mostly rain, cloud and gaseous attenuation. It is expected that ionosphere has a minor effect on the satellite signals when the ionosphere is quiet. But there are anomalies and perturbations on the structure of ionosphere with respect to geomagnetic field and solar activity and these conditions may cause further affects on the satellite signals. In this study IONOLAB-RAY algorithm is adopted to examine the effect of ionosphere on satellite signals. IONOLAB-RAY is developed to calculate propagation path and characteristics of high frequency signals. The algorithm does not have any frequency limitation and models the plasmasphere up to 20,200 km altitude, so that propagation between a GEO satellite and antenna on Earth can be simulated. The algorithm models inhomogeneous, anisotropic and time dependent structure of the ionosphere with a 3-D spherical grid geometry and calculates physical parameters of the

  19. Vocal training, levodopa, and environment effects on ultrasonic vocalizations in a rat neurotoxin model of Parkinson disease

    Science.gov (United States)

    Kelm-Nelson, Cynthia A.; Brauer, Alexander F.L.; Ciucci, Michelle R.

    2016-01-01

    Levodopa does not improve dysarthria in patients with Parkinson Disease (PD), although vocal exercise therapy, such as “LSVT/LOUD®”, does improve vocal communication. Most patients receive vocal exercise therapy while concurrently being treated with levodopa, although the interaction between levodopa and vocal exercise therapy on communication in PD is relatively unknown. Further, carryover of vocal exercise therapy to novel situations is critical for successful outcomes, but the influence of novel situations on rehabilitated vocal communication is not well understood. To address the influence of exercise, medications, and environment on vocal communication with precise experimental control, we employed the widely used 6-OHDA rat neurotoxin model of PD (infusion to the medial forebrain bundle), and assessed ultrasonic vocalizations after: vocal exercise, vocal exercise with levodopa, levodopa alone, and control conditions. We tested USVs in the familiar training environment of the home cage and a novel cage. We hypothesized that parkinsonian rats that undergo vocal exercise would demonstrate significant improvement of ultrasonic vocalization (USV) acoustic parameters as compared to the control exercise and levodopa-only treatment groups. We further hypothesized that vocal exercise in combination with levodopa administration, similar to what is common in humans, would lead to improvement in USV outcomes, particularly when tested in a familiar versus a novel environment. We found that the combination of exercise and levodopa lead to some improvement in USV acoustic parameters and these effects were stronger in a familiar vs. a novel environment. Our results suggest that although treatment can improve aspects of communication, environment can influence the benefits of these effects. PMID:27025445

  20. How low can you go? Physical production mechanism of elephant infrasonic vocalizations.

    Science.gov (United States)

    Herbst, Christian T; Stoeger, Angela S; Frey, Roland; Lohscheller, Jörg; Titze, Ingo R; Gumpenberger, Michaela; Fitch, W Tecumseh

    2012-08-03

    Elephants can communicate using sounds below the range of human hearing ("infrasounds" below 20 hertz). It is commonly speculated that these vocalizations are produced in the larynx, either by neurally controlled muscle twitching (as in cat purring) or by flow-induced self-sustained vibrations of the vocal folds (as in human speech and song). We used direct high-speed video observations of an excised elephant larynx to demonstrate flow-induced self-sustained vocal fold vibration in the absence of any neural signals, thus excluding the need for any "purring" mechanism. The observed physical principles of voice production apply to a wide variety of mammals, extending across a remarkably large range of fundamental frequencies and body sizes, spanning more than five orders of magnitude.

  1. Vocal responses of austral forest frogs to amplitude and degradation patterns of advertisement calls.

    Science.gov (United States)

    Penna, Mario; Moreno-Gómez, Felipe N; Muñoz, Matías I; Cisternas, Javiera

    2017-07-01

    Degradation phenomena affecting animal acoustic signals may provide cues to assess the distance of emitters. Recognition of degraded signals has been extensively demonstrated in birds, and recently studies have also reported detection of degraded patterns in anurans that call at or above ground level. In the current study we explore the vocal responses of the syntopic burrowing male frogs Eupsophus emiliopugini and E. calcaratus from the South American temperate forest to synthetic conspecific calls differing in amplitude and emulating degraded and non-degraded signal patterns. The results show a strong dependence of vocal responses on signal amplitude, and a general lack of differential responses to signals with different pulse amplitude modulation depths in E. emiliopugini and no effect of relative amplitude of harmonics in E. calcaratus. Such limited discrimination of signal degradation patterns from non-degraded signals is likely related to the burrowing habits of these species. Shelters amplify outgoing and incoming conspecific vocalizations, but do not counteract signal degradation to an extent comparable to calling strategies used by other frogs. The limited detection abilities and resultant response permissiveness to degraded calls in these syntopic burrowing species would be advantageous for animals communicating in circumstances in which signal alteration prevails. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. LDPC Decoding for Signal Dependent Visible Light Communication Channels

    Institute of Scientific and Technical Information of China (English)

    YUAN Ming; SHA Xiaoshi; LIANG Xiao; JIANG Ming; WANG Jiaheng; ZHAO Chunming

    2016-01-01

    Avalanche photodiodes (APD) are widely employed in visible light communication (VLC) systems. The general signal dependent Gaussian channel is investigated. Experiment results reveal that symbols on different constellation points under official illumi⁃nance inevitably suffer from different levels of noise due to the multiplication process of APDs. In such a case, conventional log likely⁃hood ratio (LLR) calculation for signal independent channels may cause performance loss. The optimal LLR calculation for decoder is then derived because of the existence of non⁃ignorable APD shot noise. To find the decoding thresholds of the optimal and suboptimal detection schemes, the extrinsic information transfer (EXIT) chat is further analyzed. Finally a modified minimum sum algorithm is suggested with reduced complexity and acceptable performance loss. Numerical simulations show that, with a reg⁃ular (3, 6) low⁃density parity check (LDPC) code of block length 20,000, 0.7 dB gain is achieved with our proposed scheme over the LDPC decoder designed for signal independent noise. It is also found that the coding performance is improved for a larger modulation depth.

  3. The evolution of coordinated vocalizations before language.

    Science.gov (United States)

    Bryant, Gregory A

    2014-12-01

    Ackermann et al. briefly point out the potential significance of coordinated vocal behavior in the dual pathway model of acoustic communication. Rhythmically entrained and articulated pre-linguistic vocal activity in early hominins might have set the evolutionary stage for later refinements that manifest in modern humans as language-based conversational turn-taking, joint music-making, and other behaviors associated with prosociality.

  4. Between cheap and costly signals: the evolution of partially honest communication.

    Science.gov (United States)

    Zollman, Kevin J S; Bergstrom, Carl T; Huttegger, Simon M

    2013-01-07

    Costly signalling theory has become a common explanation for honest communication when interests conflict. In this paper, we provide an alternative explanation for partially honest communication that does not require significant signal costs. We show that this alternative is at least as plausible as traditional costly signalling, and we suggest a number of experiments that might be used to distinguish the two theories.

  5. Auditory lateralization of conspecific and heterospecific vocalizations in cats.

    Science.gov (United States)

    Siniscalchi, Marcello; Laddago, Serena; Quaranta, Angelo

    2016-01-01

    Auditory lateralization in response to both conspecific and heterospecific vocalizations (dog vocalizations) was observed in 16 tabby cats (Felis catus). Six different vocalizations were used: cat "purring," "meowing" and "growling" and dog typical vocalizations of "disturbance," "isolation" and "play." The head-orienting paradigm showed that cats turned their head with the right ear leading (left hemisphere activation) in response to their typical-species vocalization ("meow" and "purring"); on the other hand, a clear bias in the use of the left ear (right hemisphere activation) was observed in response to vocalizations eliciting intense emotion (dogs' vocalizations of "disturbance" and "isolation"). Overall these findings suggest that auditory sensory domain seems to be lateralized also in cat species, stressing the role of the left hemisphere for intraspecific communication and of the right hemisphere in processing threatening and alarming stimuli.

  6. Vocal learning in elephants: neural bases and adaptive context.

    Science.gov (United States)

    Stoeger, Angela S; Manger, Paul

    2014-10-01

    In the last decade clear evidence has accumulated that elephants are capable of vocal production learning. Examples of vocal imitation are documented in African (Loxodonta africana) and Asian (Elephas maximus) elephants, but little is known about the function of vocal learning within the natural communication systems of either species. We are also just starting to identify the neural basis of elephant vocalizations. The African elephant diencephalon and brainstem possess specializations related to aspects of neural information processing in the motor system (affecting the timing and learning of trunk movements) and the auditory and vocalization system. Comparative interdisciplinary (from behavioral to neuroanatomical) studies are strongly warranted to increase our understanding of both vocal learning and vocal behavior in elephants.

  7. Molecular evolution of communication signals in electric fish.

    Science.gov (United States)

    Zakon, Harold H; Zwickl, Derrick J; Lu, Ying; Hillis, David M

    2008-06-01

    Animal communication systems are subject to natural selection so the imprint of selection must reside in the genome of each species. Electric fish generate electric organ discharges (EODs) from a muscle-derived electric organ (EO) and use these fields for electrolocation and communication. Weakly electric teleosts have evolved at least twice (mormyriforms, gymnotiforms) allowing a comparison of the workings of evolution in two independently evolved sensory/motor systems. We focused on the genes for two Na(+) channels, Nav1.4a and Nav1.4b, which are orthologs of the mammalian muscle-expressed Na(+) channel gene Nav1.4. Both genes are expressed in muscle in non-electric fish. Nav1.4b is expressed in muscle in electric fish, but Nav1.4a expression has been lost from muscle and gained in the evolutionarily novel EO in both groups. We hypothesized that Nav1.4a might be evolving to optimize the EOD for different sensory environments and the generation of species-specific communication signals. We obtained the sequence for Nav1.4a from non-electric, mormyriform and gymnotiform species, estimated a phylogenetic tree, and determined rates of evolution. We observed elevated rates of evolution in this gene in both groups coincident with the loss of Nav1.4a from muscle and its compartmentalization in EO. We found amino acid substitutions at sites known to be critical for channel inactivation; analyses suggest that these changes are likely to be the result of positive selection. We suggest that the diversity of EOD waveforms in both groups of electric fish is correlated with accelerations in the rate of evolution of the Nav1.4a Na(+) channel gene due to changes in selection pressure on the gene once it was solely expressed in the EO.

  8. The songbird as a percussionist: syntactic rules for non-vocal sound and song production in Java sparrows.

    Directory of Open Access Journals (Sweden)

    Masayo Soma

    Full Text Available Music and dance are two remarkable human characteristics that are closely related. Communication through integrated vocal and motional signals is also common in the courtship displays of birds. The contribution of songbird studies to our understanding of vocal learning has already shed some light on the cognitive underpinnings of musical ability. Moreover, recent pioneering research has begun to show how animals can synchronize their behaviors with external stimuli, like metronome beats. However, few studies have applied such perspectives to unraveling how animals can integrate multimodal communicative signals that have natural functions. Additionally, studies have rarely asked how well these behaviors are learned. With this in mind, here we cast a spotlight on an unusual animal behavior: non-vocal sound production associated with singing in the Java sparrow (Lonchura oryzivora, a songbird. We show that male Java sparrows coordinate their bill-click sounds with the syntax of their song-note sequences, similar to percussionists. Analysis showed that they produced clicks frequently toward the beginning of songs and before/after specific song notes. We also show that bill-clicking patterns are similar between social fathers and their sons, suggesting that these behaviors might be learned from models or linked to learning-based vocalizations. Individuals untutored by conspecifics also exhibited stereotypical bill-clicking patterns in relation to song-note sequence, indicating that while the production of bill clicking itself is intrinsic, its syncopation appears to develop with songs. This paints an intriguing picture in which non-vocal sounds are integrated with vocal courtship signals in a songbird, a model that we expect will contribute to the further understanding of multimodal communication.

  9. Female presence and estrous state influence mouse ultrasonic courtship vocalizations.

    Directory of Open Access Journals (Sweden)

    Jessica L Hanson

    Full Text Available The laboratory mouse is an emerging model for context-dependent vocal signaling and reception. Mouse ultrasonic vocalizations are robustly produced in social contexts. In adults, male vocalization during courtship has become a model of interest for signal-receiver interactions. These vocalizations can be grouped into syllable types that are consistently produced by different subspecies and strains of mice. Vocalizations are unique to individuals, vary across development, and depend on social housing conditions. The behavioral significance of different syllable types, including the contexts in which different vocalizations are made and the responses listeners have to different types of vocalizations, is not well understood. We examined the effect of female presence and estrous state on male vocalizations by exploring the use of syllable types and the parameters of syllables during courtship. We also explored correlations between vocalizations and other behaviors. These experimental manipulations produced four main findings: 1 vocalizations varied among males, 2 the production of USVs and an increase in the use of a specific syllable type were temporally related to mounting behavior, 3 the frequency (kHz, bandwidth, and duration of syllables produced by males were influenced by the estrous phase of female partners, and 4 syllable types changed when females were removed. These findings show that mouse ultrasonic courtship vocalizations are sensitive to changes in female phase and presence, further demonstrating the context-sensitivity of these calls.

  10. Comparative gene expression analysis among vocal learners (Bengalese finch and budgerigar and non-learners (quail and ring dove reveals variable cadherin expressions in the vocal system

    Directory of Open Access Journals (Sweden)

    Eiji eMatsunaga

    2011-04-01

    Full Text Available Birds use various vocalizations to communicate with one another, and some are acquired through learning. So far, three families of birds (songbirds, parrots, and hummingbirds have been identified as having vocal learning ability. Previously, we found that cadherins, a large family of cell-adhesion molecules, show vocal control-area-related expression in a songbird, the Bengalese finch. To investigate the molecular basis of evolution in avian species, we conducted comparative analysis of cadherin expressions in the vocal and other neural systems among vocal learners (Bengalese finch and budgerigar and a non-learner (quail and ring dove. The gene expression analysis revealed that cadherin expressions were more variable in vocal and auditory areas compared to vocally unrelated areas such as the visual areas among these species. Thus, it appears that such diverse cadherin expressions might have been related to generating species diversity in vocal behavior during the evolution of avian vocal learning. 

  11. Form and function of long-range vocalizations in a Neotropical fossorial rodent: the Anillaco Tuco-Tuco (Ctenomys sp.

    Directory of Open Access Journals (Sweden)

    Juan Pablo Amaya

    2016-10-01

    Full Text Available The underground environment poses particular communication challenges for subterranean rodents. Some loud and low-pitched acoustic signals that can travel long distances are appropriate for long-range underground communication and have been suggested to be territorial signals. Long-range vocalizations (LRVs are important in long-distance communication in Ctenomys tuco-tucos. We characterized the LRV of the Anillaco Tuco-Tuco (Ctenomys sp. using recordings from free-living individuals and described the behavioral context in which this vocalization was produced during laboratory staged encounters between individuals of both sexes. Long-range calls of Anillaco tuco-tucos are low-frequency, broad-band, loud, and long sounds composed by the repetition of two syllable types: series (formed by notes and soft-notes and individual notes. All vocalizations were initiated with series, but not all had individual notes. Males were heavier than females and gave significantly lower-pitched vocalizations, but acoustic features were independent of body mass in males. The pronounced variation among individuals in the arrangement and number of syllables and the existence of three types of series (dyads, triads, and tetrads, created a diverse collection of syntactic patterns in vocalizations that would provide the opportunity to encode multiple types of information. The existence of complex syntactic patterns and the description of soft-notes represent new aspects of the vocal communication of Ctenomys. Long-distance vocalizations by Anillaco Tuco-Tucos appear to be territorial signals used mostly in male-male interactions. First, emission of LRVs resulted in de-escalation or space-keeping in male-male and male-female encounters in laboratory experiments. Second, these vocalizations were produced most frequently (in the field and in the lab by males in our study population. Third, males produced LRVs with greater frequency during male-male encounters compared to

  12. Two-voice complexity from a single side of the syrinx in northern mockingbird Mimus polyglottos vocalizations.

    Science.gov (United States)

    Zollinger, Sue Anne; Riede, Tobias; Suthers, Roderick A

    2008-06-01

    The diverse vocal signals of songbirds are produced by highly coordinated motor patterns of syringeal and respiratory muscles. These muscles control separate sound generators on the right and left side of the duplex vocal organ, the syrinx. Whereas most song is under active neural control, there has been a growing interest in a different class of nonlinear vocalizations consisting of frequency jumps, subharmonics, biphonation and deterministic chaos that are also present in the vocal repertoires of many vertebrates, including many birds. These nonlinear phenomena may not require active neural control, depending instead on the intrinsic nonlinear dynamics of the oscillators housed within each side of the syrinx. This study investigates the occurrence of these phenomena in the vocalizations of intact northern mockingbirds Mimus polyglottos. By monitoring respiratory pressure and airflow on each side of the syrinx, we provide the first analysis of the contribution made by each side of the syrinx to the production of nonlinear phenomena and are able to reliably discriminate two-voice vocalizations from potentially similar appearing, unilaterally produced, nonlinear events. We present the first evidence of syringeal lateralization of nonlinear dynamics during bilaterally produced chaotic calls. The occurrence of unilateral nonlinear events was not consistently correlated with fluctuations in air sac pressure or the rate of syringeal airflow. Our data support previous hypotheses for mechanical and acoustic coupling between the two sides of the syrinx. These results help lay a foundation upon which to understand the communicative functions of nonlinear phenomena.

  13. Techniques for Vocal Health.

    Science.gov (United States)

    Wiest, Lori

    1997-01-01

    Outlines a series of simple yet effective practices, techniques, and tips for improving the singing voice and minimizing stress on the vocal chords. Describes the four components for producing vocal sound: respiration, phonation, resonation, and articulation. Provides exercises for each and lists symptoms of sickness and vocal strain. (MJP)

  14. Temporally selective processing of communication signals by auditory midbrain neurons

    DEFF Research Database (Denmark)

    Elliott, Taffeta M; Christensen-Dalsgaard, Jakob; Kelley, Darcy B

    2011-01-01

    of auditory neurons in the laminar nucleus of the torus semicircularis (TS) of X. laevis specializes in encoding vocalization click rates. We recorded single TS units while pure tones, natural calls, and synthetic clicks were presented directly to the tympanum via a vibration-stimulation probe. Synthesized...... click rates ranged from 4 to 50 Hz, the rate at which the clicks begin to overlap. Frequency selectivity and temporal processing were characterized using response-intensity curves, temporal-discharge patterns, and autocorrelations of reduplicated responses to click trains. Characteristic frequencies...

  15. VOCAL SEGMENT CLASSIFICATION IN POPULAR MUSIC

    OpenAIRE

    Feng, Ling; Nielsen, Andreas Brinch; Hansen, Lars Kai

    2008-01-01

    This paper explores the vocal and non-vocal music classification problem within popular songs. A newly built labeled database covering 147 popular songs is announced. It is designed for classifying signals from 1sec time windows. Features are selected for this particular task, in order to capture both the temporal correlations and the dependencies among the feature dimensions. We systematically study the performance of a set of classifiers, including linear regression, generalized linear mode...

  16. Improvement of a Vocal Fold Imaging System

    Energy Technology Data Exchange (ETDEWEB)

    Krauter, K. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-02-01

    Medical professionals can better serve their patients through continual update of their imaging tools. A wide range of pathologies and disease may afflict human vocal cords or, as they’re also known, vocal folds. These diseases can affect human speech hampering the ability of the patient to communicate. Vocal folds must be opened for breathing and the closed to produce speech. Currently methodologies to image markers of potential pathologies are difficult to use and often fail to detect early signs of disease. These current methodologies rely on a strobe light and slower frame rate camera in an attempt to obtain images as the vocal folds travel over the full extent of their motion.

  17. Expression of androgen receptor mRNA in the brain of Gekko gecko: implications for understanding the role of androgens in controlling auditory and vocal processes.

    Science.gov (United States)

    Tang, Y Z; Piao, Y S; Zhuang, L Z; Wang, Z W

    2001-09-17

    The neuroanatomical distribution of androgen receptor (AR) mRNA-containing cells in the brain of a vocal lizard, Gekko gecko, was mapped using in situ hybridization. Particular attention was given to auditory and vocal nuclei. Within the auditory system, the cochlear nuclei, the central nucleus of the torus semicircularis, the nucleus medialis, and the medial region of the dorsal ventricular ridge contained moderate numbers of labeled neurons. Neurons labeled with the AR probe were located in many nuclei related to vocalization. Within the hindbrain, the mesencephalic nucleus of the trigeminal nerve, the vagal part of the nucleus ambiguus, and the dosal motor nucleus of the vagus nerve contained many neurons that exhibited strong expression of AR mRNA. Neurons located in the peripheral nucleus of the torus in the mesencephalon exhibited moderate levels of hybridization. Intense AR mRNA expression was also observed in neurons within two other areas that may be involved in vocalization, the medial preoptic area and the hypoglossal nucleus. The strongest mRNA signals identified in this study were found in cells of the pallium, hypothalamus, and inferior nucleus of the raphe. The expression patterns of AR mRNA in the auditory and vocal control nuclei of G. gecko suggest that neurons involved in acoustic communication in this species, and perhaps related species, are susceptible to regulation by androgens during the breeding season. The significance of these results for understanding the evolution of reptilian vocal communication is discussed.

  18. Recording vocalizations with Bluetooth technology.

    Science.gov (United States)

    Gaona-González, Andrés; Santillán-Doherty, Ana María; Arenas-Rosas, Rita Virginia; Muñoz-Delgado, Jairo; Aguillón-Pantaleón, Miguel Angel; Ordoñez-Gómez, José Domingo; Márquez-Arias, Alejandra

    2011-06-01

    We propose a method for capturing vocalizations that is designed to avoid some of the limiting factors found in traditional bioacoustical methods, such as the impossibility of obtaining continuous long-term registers or analyzing amplitude due to the continuous change of distance between the subject and the position of the recording system. Using Bluetooth technology, vocalizations are captured and transmitted wirelessly into a receiving system without affecting the quality of the signal. The recordings of the proposed system were compared to those obtained as a reference, which were based on the coding of the signal with the so-called pulse-code modulation technique in WAV audio format without any compressing process. The evaluation showed p < .05 for the measured quantitative and qualitative parameters. We also describe how the transmitting system is encapsulated and fixed on the animal and a way to video record a spider monkey's behavior simultaneously with the audio recordings.

  19. Fear across the senses: brain responses to music, vocalizations and facial expressions.

    Science.gov (United States)

    Aubé, William; Angulo-Perkins, Arafat; Peretz, Isabelle; Concha, Luis; Armony, Jorge L

    2015-03-01

    Intrinsic emotional expressions such as those communicated by faces and vocalizations have been shown to engage specific brain regions, such as the amygdala. Although music constitutes another powerful means to express emotions, the neural substrates involved in its processing remain poorly understood. In particular, it is unknown whether brain regions typically associated with processing 'biologically relevant' emotional expressions are also recruited by emotional music. To address this question, we conducted an event-related functional magnetic resonance imaging study in 47 healthy volunteers in which we directly compared responses to basic emotions (fear, sadness and happiness, as well as neutral) expressed through faces, non-linguistic vocalizations and short novel musical excerpts. Our results confirmed the importance of fear in emotional communication, as revealed by significant blood oxygen level-dependent signal increased in a cluster within the posterior amygdala and anterior hippocampus, as well as in the posterior insula across all three domains. Moreover, subject-specific amygdala responses to fearful music and vocalizations were correlated, consistent with the proposal that the brain circuitry involved in the processing of musical emotions might be shared with the one that have evolved for vocalizations. Overall, our results show that processing of fear expressed through music, engages some of the same brain areas known to be crucial for detecting and evaluating threat-related information.

  20. Fear across the senses: brain responses to music, vocalizations and facial expressions

    Science.gov (United States)

    Angulo-Perkins, Arafat; Peretz, Isabelle; Concha, Luis; Armony, Jorge L.

    2015-01-01

    Intrinsic emotional expressions such as those communicated by faces and vocalizations have been shown to engage specific brain regions, such as the amygdala. Although music constitutes another powerful means to express emotions, the neural substrates involved in its processing remain poorly understood. In particular, it is unknown whether brain regions typically associated with processing ‘biologically relevant’ emotional expressions are also recruited by emotional music. To address this question, we conducted an event-related functional magnetic resonance imaging study in 47 healthy volunteers in which we directly compared responses to basic emotions (fear, sadness and happiness, as well as neutral) expressed through faces, non-linguistic vocalizations and short novel musical excerpts. Our results confirmed the importance of fear in emotional communication, as revealed by significant blood oxygen level-dependent signal increased in a cluster within the posterior amygdala and anterior hippocampus, as well as in the posterior insula across all three domains. Moreover, subject-specific amygdala responses to fearful music and vocalizations were correlated, consistent with the proposal that the brain circuitry involved in the processing of musical emotions might be shared with the one that have evolved for vocalizations. Overall, our results show that processing of fear expressed through music, engages some of the same brain areas known to be crucial for detecting and evaluating threat-related information. PMID:24795437

  1. The Importance of Vocal Parameters Correlation

    Directory of Open Access Journals (Sweden)

    Valentin Ghisa

    2016-06-01

    Full Text Available To analyze communication we need to study the main parameters that describe the vocal sounds from the point of view of information content transfer efficiency. In this paper we analyze the physical quality of the “on air" information transfer, according to the audio streaming parameters and from the particular phonetic nature of the human factor. Applying this statistical analysis we aim to identify and record the correlation level of the acoustical parameters with the vocal ones and the impact which the presence of this cross-correlation can have on communication structures’ improvement.

  2. Vocal Emotion of Humanoid Robots: A Study from Brain Mechanism

    Directory of Open Access Journals (Sweden)

    Youhui Wang

    2014-01-01

    Full Text Available Driven by rapid ongoing advances in humanoid robot, increasing attention has been shifted into the issue of emotion intelligence of AI robots to facilitate the communication between man-machines and human beings, especially for the vocal emotion in interactive system of future humanoid robots. This paper explored the brain mechanism of vocal emotion by studying previous researches and developed an experiment to observe the brain response by fMRI, to analyze vocal emotion of human beings. Findings in this paper provided a new approach to design and evaluate the vocal emotion of humanoid robots based on brain mechanism of human beings.

  3. Impact of Visual, Vocal, and Lexical Cues on Judgments of Counselor Qualities

    Science.gov (United States)

    Strahan, Carole; Zytowski, Donald G.

    1976-01-01

    Undergraduate students (N=130) rated Carl Rogers via visual, lexical, vocal, or vocal-lexical communication channels. Lexical cues were more important in creating favorable impressions among females. Subsequent exposure to combined visual-vocal-lexical cues resulted in warmer and less distant ratings, but not on a consistent basis. (Author)

  4. Tremulatory and abdomen vibration signals enable communication through air in the stink bug Euschistus heros.

    Directory of Open Access Journals (Sweden)

    Andreja Kavčič

    Full Text Available Communication by substrate-borne mechanical signals is widespread among animals but remains one of their least understood communication channels. Past studies of vibrational communication in insects have been oriented predominantly to communication during mating, showing that species- and sex-specific vibrational signals enable recognition and localization of potential mates on continuous solid substrates. No special attention has been paid to vibrational signals with less obvious specificity as well as to the possibility of vibrational communication across substrates that are not in physical contact. We aimed to reinvestigate emission of the aforementioned vibrational signals transmitted through a plant in the stink bug Euschistus heros (Pentatomidae: Pentatominae and to check whether individuals are able to communicate across adjecent, physically separated substrates. We used laser vibrometry for registration of substrate-borne vibrational signals on a bean plant. Using two bean plants separated for 3 to 7 cm between two most adjacent leaves, we investigated the possibility of transmission of these signals through air. Our study showed that males and females of E. heros communicate using tremulatory, percussion and buzzing signals in addition to the previously described signals produced by vibrations of the abdomen. Contrary to the latter, the first three signal types did not differ between sexes or between pentatomid species. Experiments with two physically separated plants showed significant searching behaviour and localization of vibrational signals of an E. heros male or a female, in response to abdominal vibration produced signals of a pair duetting on the neighbouring plant, in comparison to control where no animals were on the neighbouring plant. We also confirmed that transmission through air causes amplitude and frequency decay of vibrational signals, which suggests high-amplitude, low-frequency tremulatory signals of these stink bugs

  5. Desarrollo de interfaces para la detección del habla sub-vocal

    Directory of Open Access Journals (Sweden)

    Jenny Alejandra Gutiérrez Calderón

    2013-09-01

    Full Text Available This paper explores the most important techniques currently used to detect sub-vocal speech in people with cerebral palsy as well as for commercial purposes, (e.g. allow communication in very noisy places. The methodologies presented deal with speech-signal acquisition and processing. Signal detection and analysis methods are described throughout the whole speech process, from signal generation (as neural impulses in the brain to the production sound in the vocal apparatus (located in the throat. Acquisition and processing quality depends on several factors that will be presented in various sections. A brief explanation to the whole voice generation process is provided in the first part of the article. Subsequently, sub-speech signal acquisition and analysis techniques are presented. Finally, a section about the advantages and disadvantages of the various techniques is presented in order to illustrate different implementations in a sub-vocal speech or silent speech detection device. The results from research indicate that Non-audible Murmur Microphone (NAM is one of the choices that offer huge benefits, not only for signal acquisition and processing, but also for future Spanish language phoneme discrimination.

  6. Vocal tract articulation in zebra finches.

    Directory of Open Access Journals (Sweden)

    Verena R Ohms

    Full Text Available BACKGROUND: Birdsong and human vocal communication are both complex behaviours which show striking similarities mainly thought to be present in the area of development and learning. Recent studies, however, suggest that there are also parallels in vocal production mechanisms. While it has been long thought that vocal tract filtering, as it occurs in human speech, only plays a minor role in birdsong there is an increasing number of studies indicating the presence of sound filtering mechanisms in bird vocalizations as well. METHODOLOGY/PRINCIPAL FINDINGS: Correlating high-speed X-ray cinematographic imaging of singing zebra finches (Taeniopygia guttata to song structures we identified beak gape and the expansion of the oropharyngeal-esophageal cavity (OEC as potential articulators. We subsequently manipulated both structures in an experiment in which we played sound through the vocal tract of dead birds. Comparing acoustic input with acoustic output showed that OEC expansion causes an energy shift towards lower frequencies and an amplitude increase whereas a wide beak gape emphasizes frequencies around 5 kilohertz and above. CONCLUSION: These findings confirm that birds can modulate their song by using vocal tract filtering and demonstrate how OEC and beak gape contribute to this modulation.

  7. Acoustic detection of manatee vocalizations

    Science.gov (United States)

    Niezrecki, Christopher; Phillips, Richard; Meyer, Michael; Beusse, Diedrich O.

    2003-09-01

    The West Indian manatee (trichechus manatus latirostris) has become endangered partly because of a growing number of collisions with boats. A system to warn boaters of the presence of manatees, that can signal to boaters that manatees are present in the immediate vicinity, could potentially reduce these boat collisions. In order to identify the presence of manatees, acoustic methods are employed. Within this paper, three different detection algorithms are used to detect the calls of the West Indian manatee. The detection systems are tested in the laboratory using simulated manatee vocalizations from an audio compact disk. The detection method that provides the best overall performance is able to correctly identify ~96% of the manatee vocalizations. However, the system also results in a false alarm rate of ~16%. The results of this work may ultimately lead to the development of a manatee warning system that can warn boaters of the presence of manatees.

  8. Vocal matching by orange-fronted conures (Aratinga canicularis)

    DEFF Research Database (Denmark)

    Balsby, Thorsten J S; Bradbury, Jack W

    2009-01-01

    The functions of vocal matching have been clarified in territorial songbirds, compositionally stable groups of birds and mammals, and species with multiple alarm or assembly signals. The functions of vocal matching are less well understood in fission/fusion species that are non-territorial, live...

  9. The signaller's dilemma: a cost-benefit analysis of public and private communication.

    Directory of Open Access Journals (Sweden)

    Heiner Römer

    Full Text Available Understanding the diversity of animal signals requires knowledge of factors which may influence the different stages of communication, from the production of a signal by the sender up to the detection, identification and final decision-making in the receiver. Yet, many studies on signalling systems focus exclusively on the sender, and often ignore the receiver side and the ecological conditions under which signals evolve.We study a neotropical katydid which uses airborne sound for long distance communication, but also an alternative form of private signalling through substrate vibration. We quantified the strength of predation by bats which eavesdrop on the airborne sound signal, by analysing insect remains at roosts of a bat family. Males do not arbitrarily use one or the other channel for communication, but spend more time with private signalling under full moon conditions, when the nocturnal rainforest favours predation by visually hunting predators. Measurements of metabolic CO(2-production rate indicate that the energy necessary for signalling increases 3-fold in full moon nights when private signalling is favoured. The background noise level for the airborne sound channel can amount to 70 dB SPL, whereas it is low in the vibration channel in the low frequency range of the vibration signal. The active space of the airborne sound signal varies between 22 and 35 meters, contrasting with about 4 meters with the vibration signal transmitted on the insect's favourite roost plant. Signal perception was studied using neurophysiological methods under outdoor conditions, which is more reliable for the private mode of communication.Our results demonstrate the complex effects of ecological conditions, such as predation, nocturnal ambient light levels, and masking noise levels on the performance of receivers in detecting mating signals, and that the net advantage or disadvantage of a mode of communication strongly depends on these conditions.

  10. The Signaller's Dilemma: A Cost–Benefit Analysis of Public and Private Communication

    Science.gov (United States)

    Römer, Heiner; Lang, Alexander; Hartbauer, Manfred

    2010-01-01

    Background Understanding the diversity of animal signals requires knowledge of factors which may influence the different stages of communication, from the production of a signal by the sender up to the detection, identification and final decision-making in the receiver. Yet, many studies on signalling systems focus exclusively on the sender, and often ignore the receiver side and the ecological conditions under which signals evolve. Methodology/Principal Findings We study a neotropical katydid which uses airborne sound for long distance communication, but also an alternative form of private signalling through substrate vibration. We quantified the strength of predation by bats which eavesdrop on the airborne sound signal, by analysing insect remains at roosts of a bat family. Males do not arbitrarily use one or the other channel for communication, but spend more time with private signalling under full moon conditions, when the nocturnal rainforest favours predation by visually hunting predators. Measurements of metabolic CO2-production rate indicate that the energy necessary for signalling increases 3-fold in full moon nights when private signalling is favoured. The background noise level for the airborne sound channel can amount to 70 dB SPL, whereas it is low in the vibration channel in the low frequency range of the vibration signal. The active space of the airborne sound signal varies between 22 and 35 meters, contrasting with about 4 meters with the vibration signal transmitted on the insect's favourite roost plant. Signal perception was studied using neurophysiological methods under outdoor conditions, which is more reliable for the private mode of communication. Conclusions/Significance Our results demonstrate the complex effects of ecological conditions, such as predation, nocturnal ambient light levels, and masking noise levels on the performance of receivers in detecting mating signals, and that the net advantage or disadvantage of a mode of communication

  11. Vocal-tract filtering by lingual articulation in a parrot.

    Science.gov (United States)

    Beckers, Gabriël J L; Nelson, Brian S; Suthers, Roderick A

    2004-09-07

    Human speech and bird vocalization are complex communicative behaviors with notable similarities in development and underlying mechanisms. However, there is an important difference between humans and birds in the way vocal complexity is generally produced. Human speech originates from independent modulatory actions of a sound source, e.g., the vibrating vocal folds, and an acoustic filter, formed by the resonances of the vocal tract (formants). Modulation in bird vocalization, in contrast, is thought to originate predominantly from the sound source, whereas the role of the resonance filter is only subsidiary in emphasizing the complex time-frequency patterns of the source (e.g., but see ). However, it has been suggested that, analogous to human speech production, tongue movements observed in parrot vocalizations modulate formant characteristics independently from the vocal source. As yet, direct evidence of such a causal relationship is lacking. In five Monk parakeets, Myiopsitta monachus, we replaced the vocal source, the syrinx, with a small speaker that generated a broad-band sound, and we measured the effects of tongue placement on the sound emitted from the beak. The results show that tongue movements cause significant frequency changes in two formants and cause amplitude changes in all four formants present between 0.5 and 10 kHz. We suggest that lingual articulation may thus in part explain the well-known ability of parrots to mimic human speech, and, even more intriguingly, may also underlie a speech-like formant system in natural parrot vocalizations.

  12. Method of Enhancing On-Board State Estimation Using Communication Signals

    Science.gov (United States)

    Anzalone, Evan J. (Inventor); Chuang, Jason C. H. (Inventor)

    2015-01-01

    A method of enhancing on-board state estimation for a spacecraft utilizes a network of assets to include planetary-based assets and space-based assets. Communication signals transmitted from each of the assets into space are defined by a common protocol. Data is embedded in each communication signal transmitted by the assets. The data includes a time-of-transmission for a corresponding one of the communication signals and a position of a corresponding one of the assets at the time-of-transmission. A spacecraft is equipped to receive the communication signals, has a clock synchronized to the space-wide time reference frame, and has a processor programmed to generate state estimates of the spacecraft. Using its processor, the spacecraft determines a one-dimensional range from itself to at least one of the assets and then updates its state estimates using each one-dimensional range.

  13. Gestures, vocalizations and memory in language origins.

    Directory of Open Access Journals (Sweden)

    Francisco eAboitiz

    2012-02-01

    Full Text Available This article discusses the possible homologies between the human language networks and comparable auditory projection systems in the macaque brain, in an attempt to conciliate two existing views on language evolution: one that makes emphasis on hand control and gestures, and the other that makes emphasis on auditory-vocal mechanisms. The capacity for language is based on relatively well defined neural substrates whose rudiments have been traced into the non-human primate brain. In its core, this circuit makes up an auditory-vocal sensorimotor circuit with two main components, a ventral pathway connecting anterior auditory regions with anterior ventrolateral prefrontal areas, and a dorsal pathway connecting auditory areas with parietal areas and with posterior ventrolateral prefrontal areas via the arcuate fasciculus and the superior longitudinal fasciculus. In humans, the dorsal circuit is especially important for phonological processing and phonological working memory, capacities that are critical for language acquisition and for complex syntax processing. In the macaque, the homologue to the dorsal circuit overlaps with an inferior parietal-ventrolateral prefrontal network for hand and gestural action selection that is under voluntary control, while vocalizations are largely fixed and involuntary. The recruitment of this dorsal component for vocalization behavior in the human lineage, together with a direct cortical control of the subcortical vocalizing system, are proposed to have marked a fundamental innovation in human evolution, generating an inflection point that permitted the explosion of language and human communication. In this context, vocal communication and gesturing have a common history in primate communication.

  14. Reinforcement of Infant Vocalizations through Contingent Vocal Imitation

    Science.gov (United States)

    Pelaez, Martha; Virues-Ortega, Javier; Gewirtz, Jacob L.

    2011-01-01

    Maternal vocal imitation of infant vocalizations is highly prevalent during face-to-face interactions of infants and their caregivers. Although maternal vocal imitation has been associated with later verbal development, its potentially reinforcing effect on infant vocalizations has not been explored experimentally. This study examined the…

  15. Vocal production complexity correlates with neural instructions in the oyster toadfish (Opsanus tau).

    Science.gov (United States)

    Elemans, Coen P H; Mensinger, Allen F; Rome, Lawrence C

    2014-06-01

    Sound communication is fundamental to many social interactions and essential to courtship and agonistic behaviours in many vertebrates. The swimbladder and associated muscles in batrachoidid fishes (midshipman and toadfish) is a unique vertebrate sound production system, wherein fundamental frequencies are determined directly by the firing rate of a vocal-acoustic neural network that drives the contraction frequency of superfast swimbladder muscles. The oyster toadfish boatwhistle call starts with an irregular sound waveform that could be an emergent property of the peripheral nonlinear sound-producing system or reflect complex encoding in the central nervous system. Here, we demonstrate that the start of the boatwhistle is indicative of a chaotic strange attractor, and tested whether its origin lies in the peripheral sound-producing system or in the vocal motor network. We recorded sound and swimbladder muscle activity in awake, freely behaving toadfish during motor nerve stimulation, and recorded sound, motor nerve and muscle activity during spontaneous grunts. The results show that rhythmic motor volleys do not cause complex sound signals. However, arrhythmic recruitment of swimbladder muscle during spontaneous grunts correlates with complex sounds. This supports the hypothesis that the irregular start of the boatwhistle is encoded in the vocal pre-motor neural network, and not caused by peripheral interactions with the sound-producing system. We suggest that sound production system demands across vocal tetrapods have selected for muscles and motorneurons adapted for speed, which can execute complex neural instructions into equivalently complex vocalisations. © 2014. Published by The Company of Biologists Ltd.

  16. Enhanced method with superposed signal-based visible light communication system using multiple-input signal-output beamforming

    Science.gov (United States)

    Qiao, Liang; Liang, Shangyu; Lu, Xingyu; Zhou, Yingjun; Jiang, Yi; Chi, Nan

    2017-08-01

    As a promising candidate technology for the next generation communication systems, visible light communication (VLC), combined with high modulation and coding schemes, can be used to achieve throughput much higher than the traditional RF wireless ones. We propose adopting multiple light-emitting diodes (LEDs) on the transmit side to form a multiple-input signal-output (MISO) VLC system. Through the maximum ratio transmit beamforming, the signals from the multiple LEDs can be added coherently at the receiver side, and, therefore, the signal-to-noise ratio of the system can be improved slightly. Meanwhile, a method of channel estimation with superposed signal is employed for better channel estimation. Extensive lab experiments demonstrate that a two-LED MISO-VLC system can achieve a data rate of 1.0 Gbit/s over a free-space link of 1.2 m.

  17. Vocal attractiveness increases by averaging.

    Science.gov (United States)

    Bruckert, Laetitia; Bestelmeyer, Patricia; Latinus, Marianne; Rouger, Julien; Charest, Ian; Rousselet, Guillaume A; Kawahara, Hideki; Belin, Pascal

    2010-01-26

    Vocal attractiveness has a profound influence on listeners-a bias known as the "what sounds beautiful is good" vocal attractiveness stereotype [1]-with tangible impact on a voice owner's success at mating, job applications, and/or elections. The prevailing view holds that attractive voices are those that signal desirable attributes in a potential mate [2-4]-e.g., lower pitch in male voices. However, this account does not explain our preferences in more general social contexts in which voices of both genders are evaluated. Here we show that averaging voices via auditory morphing [5] results in more attractive voices, irrespective of the speaker's or listener's gender. Moreover, we show that this phenomenon is largely explained by two independent by-products of averaging: a smoother voice texture (reduced aperiodicities) and a greater similarity in pitch and timbre with the average of all voices (reduced "distance to mean"). These results provide the first evidence for a phenomenon of vocal attractiveness increases by averaging, analogous to a well-established effect of facial averaging [6, 7]. They highlight prototype-based coding [8] as a central feature of voice perception, emphasizing the similarity in the mechanisms of face and voice perception.

  18. Acute exposure to vibration is an apoptosis-inducing stimulus in the vocal fold epithelium.

    Science.gov (United States)

    Novaleski, Carolyn K; Kimball, Emily E; Mizuta, Masanobu; Rousseau, Bernard

    2016-10-01

    Clinical voice disorders pose significant communication-related challenges to patients. The purpose of this study was to quantify the rate of apoptosis and tumor necrosis factor-alpha (TNF-α) signaling in vocal fold epithelial cells in response to increasing time-doses and cycle-doses of vibration. 20 New Zealand white breeder rabbits were randomized to three groups of time-doses of vibration exposure (30, 60, 120min) or a control group (120min of vocal fold adduction and abduction). Estimated cycle-doses of vocal fold vibration were extrapolated based on mean fundamental frequency. Laryngeal tissue specimens were evaluated for apoptosis and gene transcript and protein levels of TNF-α. Results revealed that terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was significantly higher after 120min of vibration compared to the control. Transmission electron microscopy (TEM) revealed no significant effect of time-dose on the mean area of epithelial cell nuclei. Extrapolated cycle-doses of vibration exposure were closely related to experimental time-dose conditions, although no significant correlations were observed with TUNEL staining or mean area of epithelial cell nuclei. TUNEL staining was positively correlated with TNF-α protein expression. Our findings suggest that apoptosis can be induced in the vocal fold epithelium after 120min of modal intensity phonation. In contrast, shorter durations of vibration exposure do not result in apoptosis signaling. However, morphological features of apoptosis are not observed using TEM. Future studies are necessary to examine the contribution of abnormal apoptosis to vocal fold diseases.

  19. Information Transmission in Communication Games Signaling with an Audience

    Science.gov (United States)

    Satari, Farishta

    2013-01-01

    Communication is a goal-oriented activity where interlocutors use language as a means to achieve an end while taking into account the goals and plans of others. Game theory, being the scientific study of strategically interactive decision-making, provides the mathematical tools for modeling language use among rational decision makers. When we…

  20. Bonobos (Pan paniscus) vocally protest against violations of social expectations.

    Science.gov (United States)

    Clay, Zanna; Ravaux, Lucie; de Waal, Frans B M; Zuberbühler, Klaus

    2016-02-01

    Research has shown that great apes possess certain expectations about social regularities and both perceive and act according to social rules within their group. During natural and experimentally induced contexts, such as the inequitable distribution of resources, individuals also show protesting behaviors when their expectations about a social situation are violated. Despite broad interest in this topic, systematic research examining the nature of these expectations and the communicative signals individuals use to express them remains scant. Here, we addressed this by exploring whether bonobos (Pan paniscus) respond to violations of social expectations in naturally occurring social interactions, focusing on the vocal behavior of victims following socially expected and unexpected aggression. Expected aggression included conflicts over a contested resource and conflicts that were provoked by the victim. Unexpected aggression was any spontaneous, unprovoked hostility toward the victim. For each conflict, we also determined its severity and the composition of the nearby audience. We found that the acoustic and temporal structure of victim screams was individually distinct and varied significantly depending on whether or not aggression could be socially predicted. Certain acoustic parameters also varied as a function of conflict severity, but unlike social expectation, conflict severity did not discriminate scream acoustic structure overall. We found no effect of audience composition. We concluded that, beyond the physical nature of a conflict, bonobos possess certain social expectations about how they should be treated and will publicly protest with acoustically distinctive vocal signals if these expectations are violated.

  1. Speech intelligibility measure for vocal control of an automaton

    Science.gov (United States)

    Naranjo, Michel; Tsirigotis, Georgios

    1998-07-01

    The acceleration of investigations in Speech Recognition allows to augur, in the next future, a wide establishment of Vocal Control Systems in the production units. The communication between a human and a machine necessitates technical devices that emit, or are submitted to important noise perturbations. The vocal interface introduces a new control problem of a deterministic automaton using uncertain information. The purpose is to place exactly the automaton in a final state, ordered by voice, from an unknown initial state. The whole Speech Processing procedure, presented in this paper, has for input the temporal speech signal of a word and for output a recognised word labelled with an intelligibility index given by the recognition quality. In the first part, we present the essential psychoacoustic concepts for the automatic calculation of the loudness of a speech signal. The architecture of a Time Delay Neural Network is presented in second part where we also give the results of the recognition. The theory of the fuzzy subset, in third part, allows to extract at the same time a recognised word and its intelligibility index. In the fourth part, an Anticipatory System models the control of a Sequential Machine. A prediction phase and an updating one appear which involve data coming from the information system. A Bayesian decision strategy is used and the criterion is a weighted sum of criteria defined from information, minimum path functions and speech intelligibility measure.

  2. Individual killer whale vocal variation during intra-group behavioral dynamics

    Science.gov (United States)

    Grebner, Dawn M.

    The scientific goal of this dissertation was to carefully study the signal structure of killer whale communications and vocal complexity and link them to behavioral circumstances. The overall objective of this research sought to provide insight into killer whale call content and usage which may be conveying information to conspecifics in order to maintain group cohesion. Data were collected in the summers of 2006 and 2007 in Johnstone Strait, British Columbia. For both individuals and small groups, vocalizations were isolated using a triangular hydrophone array and the behavioral movement patterns were captured by a theodolite and video camera positioned on a cliff overlooking the hyrophone locations. This dissertation is divided into four analysis chapters. In Chapter 3, discriminant analysis was used to validate the four N04 call subtypes which were originally parsed due to variations in slope segments. The first two functions of the discriminant analysis explained 97% of the variability. Most of the variability for the N04 call was found in the front convex and the terminal portions of the call, while very little variability was found in the center region of the call. This research revealed that individual killer whales produced multiple subtypes of the N04 call. No correlations of behaviors to acoustic parameters obtained were found. The aim of the Chapter 4 was to determine if killer whale calling behavior varied prior to and after the animals had joined. Pulsed call rates were found to be greater pre- compared to post-joining events. Two-way vocal exchanges were more common occurring 74% of the time during pre-joining events. In Chapter 5, initiated and first response to calls varied between age/sex class groups when mothers were separated from an offspring. Solo mothers and calves initiated pulsed calls more often than they responded. Most of the no vocal responses were due to mothers who were foraging. Finally, observations of the frequency split in N04

  3. Feature extraction for two-way automatic communication system outbound signal

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Presents TWACS, a new communication technology with unique advantages in many regions for power dis tribution networks and singularity detection with wavelet transform, a new valuable way of detecting TWACS signals, and concludes with field results that it has the ability to distinguish TWACS modulation signals effectively from many different noises.

  4. Shallow-water acoustic communication with high bit rate BPSK signals

    NARCIS (Netherlands)

    Gijzen, M.B. van; Walree, P.A. van

    2000-01-01

    BPSK signals have been defined for transmission through a shallow-water acoustic communication channel. The signals were accompanied by two displaced carriers to facilitate carrier recovery. To correct for the adverse effects of time spreading, a pseudo-random learning sequence was transmitted ahead

  5. Representation of complex vocalizations in the Lusitanian toadfish auditory system: evidence of fine temporal, frequency and amplitude discrimination.

    Science.gov (United States)

    Vasconcelos, Raquel O; Fonseca, Paulo J; Amorim, M Clara P; Ladich, Friedrich

    2011-03-22

    Many fishes rely on their auditory skills to interpret crucial information about predators and prey, and to communicate intraspecifically. Few studies, however, have examined how complex natural sounds are perceived in fishes. We investigated the representation of conspecific mating and agonistic calls in the auditory system of the Lusitanian toadfish Halobatrachus didactylus, and analysed auditory responses to heterospecific signals from ecologically relevant species: a sympatric vocal fish (meagre Argyrosomus regius) and a potential predator (dolphin Tursiops truncatus). Using auditory evoked potential (AEP) recordings, we showed that both sexes can resolve fine features of conspecific calls. The toadfish auditory system was most sensitive to frequencies well represented in the conspecific vocalizations (namely the mating boatwhistle), and revealed a fine representation of duration and pulsed structure of agonistic and mating calls. Stimuli and corresponding AEP amplitudes were highly correlated, indicating an accurate encoding of amplitude modulation. Moreover, Lusitanian toadfish were able to detect T. truncatus foraging sounds and A. regius calls, although at higher amplitudes. We provide strong evidence that the auditory system of a vocal fish, lacking accessory hearing structures, is capable of resolving fine features of complex vocalizations that are probably important for intraspecific communication and other relevant stimuli from the auditory scene.

  6. Representation of complex vocalizations in the Lusitanian toadfish auditory system: evidence of fine temporal, frequency and amplitude discrimination

    Science.gov (United States)

    Vasconcelos, Raquel O.; Fonseca, Paulo J.; Amorim, M. Clara P.; Ladich, Friedrich

    2011-01-01

    Many fishes rely on their auditory skills to interpret crucial information about predators and prey, and to communicate intraspecifically. Few studies, however, have examined how complex natural sounds are perceived in fishes. We investigated the representation of conspecific mating and agonistic calls in the auditory system of the Lusitanian toadfish Halobatrachus didactylus, and analysed auditory responses to heterospecific signals from ecologically relevant species: a sympatric vocal fish (meagre Argyrosomus regius) and a potential predator (dolphin Tursiops truncatus). Using auditory evoked potential (AEP) recordings, we showed that both sexes can resolve fine features of conspecific calls. The toadfish auditory system was most sensitive to frequencies well represented in the conspecific vocalizations (namely the mating boatwhistle), and revealed a fine representation of duration and pulsed structure of agonistic and mating calls. Stimuli and corresponding AEP amplitudes were highly correlated, indicating an accurate encoding of amplitude modulation. Moreover, Lusitanian toadfish were able to detect T. truncatus foraging sounds and A. regius calls, although at higher amplitudes. We provide strong evidence that the auditory system of a vocal fish, lacking accessory hearing structures, is capable of resolving fine features of complex vocalizations that are probably important for intraspecific communication and other relevant stimuli from the auditory scene. PMID:20861044

  7. Research on Processing Multi-noise Signals in Mobile Multimedia Communication Based on HFC

    Institute of Scientific and Technical Information of China (English)

    ZENG Qinghui; HU Xiulin; ZHUANG Zhaowen; ZENG Yilin; MA Tao; ZHANG Yunyu; YANG Haizhou

    2001-01-01

    As well known, noise is one of mainobjects of signals processing. However, many kindsof noises are affecting widely on mobile communica-tion along with enlarging mobile networks and rapidlyincreasing application range of multimedia commu-nication. The noises include 1/f noise; burst noise;multichannel noise; thermal and shot noise etc., allof which here are called "multi-noise (MN)" and atthe same time, the signals affected by "multi-noise"is called "multi-noise signals". The article firstly ana-lyzes some disturbance factors of multi-noise that af-fects multimedia flow. Then, it describes briefly hi-erarchical fuzzy control (HFC) technology and its ap-plication procedure for online identification and con-trolling multi-noise signals in mobile multimedia com-munication networks. Lastly, how to make a specialhierarchical fuzzy control program is also discussed.With different test examples, the article demonstratesthe ability of hierarchical fuzzy control to identifyflow states and control signal distortion in multime-dia communication. The hierarchical fuzzy controland hierarchical fuzzy control programs provide anadvanced efficient tool for supervising the distributedstates of multi-noise and movement characteristics ofmulti-noise signals in mobile multimedia communica-tion.

  8. Characterizing noise in nonhuman vocalizations: Acoustic analysis and human perception of barks by coyotes and dogs

    Science.gov (United States)

    Riede, Tobias; Mitchell, Brian R.; Tokuda, Isao; Owren, Michael J.

    2005-07-01

    Measuring noise as a component of mammalian vocalizations is of interest because of its potential relevance to the communicative function. However, methods for characterizing and quantifying noise are less well established than methods applicable to harmonically structured aspects of signals. Using barks of coyotes and domestic dogs, we compared six acoustic measures and studied how they are related to human perception of noisiness. Measures of harmonic-to-noise-ratio (HNR), percent voicing, and shimmer were found to be the best predictors of perceptual rating by human listeners. Both acoustics and perception indicated that noisiness was similar across coyote and dog barks, but within each species there was significant variation among the individual vocalizers. The advantages and disadvantages of the various measures are discussed.

  9. Extraction of periodic signals in chaotic secure communication using Duffing oscillators

    Institute of Scientific and Technical Information of China (English)

    Wang Yun-Cai; Zhao Qing-Chun; Wang An-Bang

    2008-01-01

    This paper presents a novel approach to extract the periodic signals masked by a chaotic carrier. It verifies that the driven Duffing oscillator is immune to the chaotic carrier and sensitive to certain periodic signals. A preliminary detection scenario illustrates that the frequency and amplitude of the hidden sine wave signal can be extracted from the chaotic carrier by numerical simulation. The obtained results indicate that the hidden messages in chaotic secure communication can be eavesdropped utilizing Duffing oscillators.

  10. Unified Processing Structure for Communication and Navigation signals in modems for lightweight satellite stations

    Directory of Open Access Journals (Sweden)

    Y.N. Antonov-Antipov (R.I.P.

    2012-10-01

    Full Text Available The present article shows the design and test of a unified-processing device for detection and demodulation of narrowand broadband communication signals, as well as navigation signals from GLONASS and GPS systems. The specificprocessing for each type of signal is described within the general framework of the proposed device. Performanceindicators, such as symbol error probability (SEP and energy losses, were computed using simulations of the deviceand the corresponding results are presented for discussion.

  11. Active Harmonic Load–Pull With Realistic Wideband Communications Signals

    NARCIS (Netherlands)

    Marchetti, M.; Pelk, M.J.; Buisman, K.; Neo, W.C.E.; Spirito, M.; De Vreede, L.C.N.

    2008-01-01

    A new wideband open-loop active harmonic load–pull measurement approach is presented. The proposed method is based on wideband data-acquisition and wideband signal-injection of the incident and device generated power waves at the frequencies of interest. The system provides full, user defined, in-ba

  12. Bluetooth Communication Interface for EEG Signal Recording in Hyperbaric Chambers.

    Science.gov (United States)

    Pastena, Lucio; Formaggio, Emanuela; Faralli, Fabio; Melucci, Massimo; Rossi, Marco; Gagliardi, Riccardo; Ricciardi, Lucio; Storti, Silvia F

    2015-07-01

    Recording biological signals inside a hyperbaric chamber poses technical challenges (the steel walls enclosing it greatly attenuate or completely block the signals as in a Faraday cage), practical (lengthy cables creating eddy currents), and safety (sparks hazard from power supply to the electronic apparatus inside the chamber) which can be overcome with new wireless technologies. In this technical report we present the design and implementation of a Bluetooth system for electroencephalographic (EEG) recording inside a hyperbaric chamber and describe the feasibility of EEG signal transmission outside the chamber. Differently from older systems, this technology allows the online recording of amplified signals, without interference from eddy currents. In an application of this technology, we measured EEG activity in professional divers under three experimental conditions in a hyperbaric chamber to determine how oxygen, assumed at a constant hyperbaric pressure of 2.8 ATA , affects the bioelectrical activity. The EEG spectral power estimated by fast Fourier transform and the cortical sources of the EEG rhythms estimated by low-resolution brain electromagnetic analysis were analyzed in three different EEG acquisitions: breathing air at sea level; breathing oxygen at a simulated depth of 18 msw, and breathing air at sea level after decompression.

  13. VOCAL SEGMENT CLASSIFICATION IN POPULAR MUSIC

    DEFF Research Database (Denmark)

    Feng, Ling; Nielsen, Andreas Brinch; Hansen, Lars Kai

    2008-01-01

    This paper explores the vocal and non-vocal music classification problem within popular songs. A newly built labeled database covering 147 popular songs is announced. It is designed for classifying signals from 1sec time windows. Features are selected for this particular task, in order to capture......-validated training and test setup. The database is divided in two different ways: with/without artist overlap between training and test sets, so as to study the so called ‘artist effect’. The performance and results are analyzed in depth: from error rates to sample-to-sample error correlation. A voting scheme...

  14. Experimental evaluation of a radio-on-FSO communication system for multiple RF signal transmission

    Science.gov (United States)

    Kazaura, Kamugisha; Dat, Pham; Bekkali, Abdelmoula; Shah, Alam; Suzuki, Toshiji; Wakamori, Kazuhiko; Matsumoto, Mitsuji; Nakamura, Takuya; Takahashi, Koichi; Higashino, Takeshi; Aburakawa, Yuji; Tsukamoto, Katsutoshi; Komaki, Shozo

    2009-02-01

    In this paper we present the design concept plus experimental results and evaluation of a newly developed advanced DWDM Radio-on-Free-Space Optical (RoFSO) communication system capable of simultaneous transmission of multiple RF signals. The RoFSO system is evaluated based on the performance metric parameters defined for the various RF signals comprising of different wireless services including terrestrial digital broadcasting signals, cellular 3GPP W-CDMA signals, IEEE 802.11 WLAN based signals etc being transmitted over the RoFSO link. The performance metric parameters being considered include standard optical received power, CNR and BER characteristics, W-CDMA signal transmission metric parameters like Adjacent Channel Leakage Ratio (ACLR) and Error Vector Magnitude (EVM), modulation error ratio (MER) for digital terrestrial television broadcasting signals as well as spectrum mask and EVM for IEEE 802.11 Wireless LAN signal transmission.

  15. Human sensorimotor communication: a theory of signaling in online social interactions.

    Science.gov (United States)

    Pezzulo, Giovanni; Donnarumma, Francesco; Dindo, Haris

    2013-01-01

    Although the importance of communication is recognized in several disciplines, it is rarely studied in the context of online social interactions and joint actions. During online joint actions, language and gesture are often insufficient and humans typically use non-verbal, sensorimotor forms of communication to send coordination signals. For example, when playing volleyball, an athlete can exaggerate her movements to signal her intentions to her teammates (say, a pass to the right) or to feint an adversary. Similarly, a person who is transporting a table together with a co-actor can push the table in a certain direction to signal where and when he intends to place it. Other examples of "signaling" are over-articulating in noisy environments and over-emphasizing vowels in child-directed speech. In all these examples, humans intentionally modify their action kinematics to make their goals easier to disambiguate. At the moment no formal theory exists of these forms of sensorimotor communication and signaling. We present one such theory that describes signaling as a combination of a pragmatic and a communicative action, and explains how it simplifies coordination in online social interactions. We cast signaling within a "joint action optimization" framework in which co-actors optimize the success of their interaction and joint goals rather than only their part of the joint action. The decision of whether and how much to signal requires solving a trade-off between the costs of modifying one's behavior and the benefits in terms of interaction success. Signaling is thus an intentional strategy that supports social interactions; it acts in concert with automatic mechanisms of resonance, prediction, and imitation, especially when the context makes actions and intentions ambiguous and difficult to read. Our theory suggests that communication dynamics should be studied within theories of coordination and interaction rather than only in terms of the maximization of information

  16. Resting-associated vocalization emitted by captive Asian house shrews (Suncus murinus: acoustic structure and variability in an unusual mammalian vocalization.

    Directory of Open Access Journals (Sweden)

    Irena Schneiderová

    Full Text Available Shrews have rich vocal repertoires that include vocalizations within the human audible frequency range and ultrasonic vocalizations. Here, we recorded and analyzed in detail the acoustic structure of a vocalization with unclear functional significance that was spontaneously produced by 15 adult, captive Asian house shrews (Suncus murinus while they were lying motionless and resting in their nests. This vocalization was usually emitted repeatedly in a long series with regular intervals. It showed some structural variability; however, the shrews most frequently emitted a tonal, low-frequency vocalization with minimal frequency modulation and a low, non-vocal click that was clearly noticeable at its beginning. There was no effect of sex, but the acoustic structure of the analyzed vocalizations differed significantly between individual shrews. The encoded individuality was low, but it cannot be excluded that this individuality would allow discrimination of family members, i.e., a male and female with their young, collectively resting in a common nest. The question remains whether the Asian house shrews indeed perceive the presence of their mates, parents or young resting in a common nest via the resting-associated vocalization and whether they use it to discriminate among their family members. Additional studies are needed to explain the possible functional significance of resting-associated vocalizations emitted by captive Asian house shrews. Our study highlights that the acoustic communication of shrews is a relatively understudied topic, particularly considering that they are highly vocal mammals.

  17. Covert communications using random noise signals: overall system simulation and modulation analysis

    Science.gov (United States)

    Chuang, Jack; Narayanan, Ram M.

    2005-06-01

    In military communications, there exist numerous potential threats to message security. Ultra-wideband (UWB) signals provide secure communications because they cannot, in general, be detected using conventional receivers and they can be made relatively immune from jamming. The security of an UWB signal can be further improved by mixing it with random noise. By using a random noise signal, the user can conceal the message signal within the noise waveform and thwart detection by hostile forces. This paper describes a novel spread spectrum technique that can be used for secure and covert communications. The technique is based on the use of heterodyne correlation techniques to inject coherence in a random noise signal. The modulated signal to be transmitted containing the coherent carrier is mixed with a sample of an ultrawideband random noise signal. The frequency range of the ultra-wideband noise signal is appropriately chosen so that the lower sideband of the mixing process falls over the same frequency range. Both the frequency-converted noise-like signal and the original random noise signal are simultaneously transmitted on orthogonally polarized channels through a dual-polarized transmitting antenna. The receiver consists of a similar dual-polarized antenna that simultaneously receives the two orthogonally polarized transmitted signals, amplifies each in a minimum phase limiting amplifier, and mixes these signals in a double sideband up-converter. The upper sideband of the mixing process recovers the modulated signal, which can then be demodulated. The advantage of this technique lies in the relative immunity of the random noise-like un-polarized transmit signal from detection and jamming. Since the transmit signal "appears" totally un-polarized and noise-like, linearly polarized receivers are unable to identify, decode, or otherwise extract useful information from the signal. The system is immune from interference caused by high power linearly polarized signal

  18. A Linear Subspace Approach to Burst Communication Signal Processing

    Science.gov (United States)

    2006-05-31

    estimators, likelihood ra- tio detectors, and Cramér–Rao bounds, became a simple matter of calculation. This simple beginning then led to improved signal...is a vector, vector gradient formulas are applicable. The following are defined for real vectors, dr (or equivalently di). ∇drdTr x = x (237) ∇ drx †dr...Structural Characterization of Locally Optimum Detec- tors in Terms of Locally Optimum Estimators and Correlators,” IEEE Transac- tions on Information

  19. Gelada vocal sequences follow Menzerath's linguistic law.

    Science.gov (United States)

    Gustison, Morgan L; Semple, Stuart; Ferrer-I-Cancho, Ramon; Bergman, Thore J

    2016-05-10

    Identifying universal principles underpinning diverse natural systems is a key goal of the life sciences. A powerful approach in addressing this goal has been to test whether patterns consistent with linguistic laws are found in nonhuman animals. Menzerath's law is a linguistic law that states that, the larger the construct, the smaller the size of its constituents. Here, to our knowledge, we present the first evidence that Menzerath's law holds in the vocal communication of a nonhuman species. We show that, in vocal sequences of wild male geladas (Theropithecus gelada), construct size (sequence size in number of calls) is negatively correlated with constituent size (duration of calls). Call duration does not vary significantly with position in the sequence, but call sequence composition does change with sequence size and most call types are abbreviated in larger sequences. We also find that intercall intervals follow the same relationship with sequence size as do calls. Finally, we provide formal mathematical support for the idea that Menzerath's law reflects compression-the principle of minimizing the expected length of a code. Our findings suggest that a common principle underpins human and gelada vocal communication, highlighting the value of exploring the applicability of linguistic laws in vocal systems outside the realm of language.

  20. Wavelet based detection of manatee vocalizations

    Science.gov (United States)

    Gur, Berke M.; Niezrecki, Christopher

    2005-04-01

    The West Indian manatee (Trichechus manatus latirostris) has become endangered partly because of watercraft collisions in Florida's coastal waterways. Several boater warning systems, based upon manatee vocalizations, have been proposed to reduce the number of collisions. Three detection methods based on the Fourier transform (threshold, harmonic content and autocorrelation methods) were previously suggested and tested. In the last decade, the wavelet transform has emerged as an alternative to the Fourier transform and has been successfully applied in various fields of science and engineering including the acoustic detection of dolphin vocalizations. As of yet, no prior research has been conducted in analyzing manatee vocalizations using the wavelet transform. Within this study, the wavelet transform is used as an alternative to the Fourier transform in detecting manatee vocalizations. The wavelet coefficients are analyzed and tested against a specified criterion to determine the existence of a manatee call. The performance of the method presented is tested on the same data previously used in the prior studies, and the results are compared. Preliminary results indicate that using the wavelet transform as a signal processing technique to detect manatee vocalizations shows great promise.

  1. Effects of Parental Interaction on Infant Vocalization Rate, Variability and Vocal Type

    Science.gov (United States)

    Franklin, Beau; Warlaumont, Anne S.; Messinger, Daniel; Bene, Edina; Iyer, Suneeti Nathani; Lee, Chia-Chang; Lambert, Brittany; Oller, D. Kimbrough

    2014-01-01

    Examination of infant vocalization patterns across interactive and noninteractive contexts may facilitate better understanding of early communication development. In the current study, with 24 infant-parent dyads, infant volubility increased significantly when parent interaction ceased (presenting a "still face," or SF) after a period of…

  2. Gender and vocal production mode discrimination using the high frequencies for speech and singing.

    Science.gov (United States)

    Monson, Brian B; Lotto, Andrew J; Story, Brad H

    2014-01-01

    Humans routinely produce acoustical energy at frequencies above 6 kHz during vocalization, but this frequency range is often not represented in communication devices and speech perception research. Recent advancements toward high-definition (HD) voice and extended bandwidth hearing aids have increased the interest in the high frequencies. The potential perceptual information provided by high-frequency energy (HFE) is not well characterized. We found that humans can accomplish tasks of gender discrimination and vocal production mode discrimination (speech vs. singing) when presented with acoustic stimuli containing only HFE at both amplified and normal levels. Performance in these tasks was robust in the presence of low-frequency masking noise. No substantial learning effect was observed. Listeners also were able to identify the sung and spoken text (excerpts from "The Star-Spangled Banner") with very few exposures. These results add to the increasing evidence that the high frequencies provide at least redundant information about the vocal signal, suggesting that its representation in communication devices (e.g., cell phones, hearing aids, and cochlear implants) and speech/voice synthesizers could improve these devices and benefit normal-hearing and hearing-impaired listeners.

  3. Gender and vocal production mode discrimination using the high frequencies for speech and singing

    Directory of Open Access Journals (Sweden)

    Brian B Monson

    2014-10-01

    Full Text Available Humans routinely create acoustical energy at frequencies above 6 kHz during vocalization, but this frequency range is often not represented in communication devices and speech perception research. Recent advancements toward HD voice and extended bandwidth hearing aids have increased the interest in the high frequencies. The potential perceptual information provided by high-frequency energy (HFE is not well characterized. We found that humans can accomplish tasks of gender discrimination and vocal production mode discrimination (speech vs. singing when presented with acoustic stimuli containing only HFE at both amplified and normal levels. Performance in these tasks was robust in the presence of low-frequency masking noise. No substantial learning effect was observed. Listeners also were able to identify the sung and spoken text (excerpts from The Star-Spangled Banner with very few exposures. These results add to the increasing evidence that the high frequencies provide at least redundant information about the vocal signal, suggesting that its representation in communication devices (e.g., cell phones, hearing aids, and cochlear implants and speech/voice synthesizers could improve these devices and benefit normal-hearing and hearing-impaired listeners.

  4. Vocalizations in juvenile anurans: common spadefoot toads (Pelobates fuscus) regularly emit calls before sexual maturity.

    Science.gov (United States)

    Ten Hagen, Leonie; Rodríguez, Ariel; Menke, Norbert; Göcking, Christian; Bisping, Michael; Frommolt, Karl-Heinz; Ziegler, Thomas; Bonkowski, Michael; Vences, Miguel

    2016-10-01

    Acoustic communication is prominent in adult anuran amphibians, in reproductive, territorial and defensive contexts. In contrast, reports on vocalizations of juvenile anurans are rare and anecdotal, and their function unstudied. We here provide conclusive evidence for vocalizations in juvenile spadefoot toads (Pelobates fuscus) in very early terrestrial stages. While the aquatic tadpoles did not emit sounds, first vocalizations of metamorphs were heard as early as in stages 42-43, and calls were regularly emitted from stage 44 on, often from specimens still bearing extensive tail stubs. Three main types of calls could be distinguished, of which one consists of a series of short notes, one of a typically single longer and pulsed note, and one of a single tonal note. In experimental setups, the number of calls per froglet increased with density of individuals and after feeding, while on the contrary calls were not elicited by playback. The function of these juvenile calls remains unclarified, but they might reflect a general arousal in the context of feeding. Further evidence is necessary to test whether such feeding calls could confer a signal to conspecifics and thus might represent intraspecific acoustic communication in these immature terrestrial amphibians.

  5. Coherent detection and digital signal processing for fiber optic communications

    Science.gov (United States)

    Ip, Ezra

    The drive towards higher spectral efficiency in optical fiber systems has generated renewed interest in coherent detection. We review different detection methods, including noncoherent, differentially coherent, and coherent detection, as well as hybrid detection methods. We compare the modulation methods that are enabled and their respective performances in a linear regime. An important system parameter is the number of degrees of freedom (DOF) utilized in transmission. Polarization-multiplexed quadrature-amplitude modulation maximizes spectral efficiency and power efficiency as it uses all four available DOF contained in the two field quadratures in the two polarizations. Dual-polarization homodyne or heterodyne downconversion are linear processes that can fully recover the received signal field in these four DOF. When downconverted signals are sampled at the Nyquist rate, compensation of transmission impairments can be performed using digital signal processing (DSP). Software based receivers benefit from the robustness of DSP, flexibility in design, and ease of adaptation to time-varying channels. Linear impairments, including chromatic dispersion (CD) and polarization-mode dispersion (PMD), can be compensated quasi-exactly using finite impulse response filters. In practical systems, sampling the received signal at 3/2 times the symbol rate is sufficient to enable an arbitrary amount of CD and PMD to be compensated for a sufficiently long equalizer whose tap length scales linearly with transmission distance. Depending on the transmitted constellation and the target bit error rate, the analog-to-digital converter (ADC) should have around 5 to 6 bits of resolution. Digital coherent receivers are naturally suited for the implementation of feedforward carrier recovery, which has superior linewidth tolerance than phase-locked loops, and does not suffer from feedback delay constraints. Differential bit encoding can be used to prevent catastrophic receiver failure due

  6. Discrete Input Signaling for MISO Visible Light Communication Channels

    KAUST Repository

    Arfaoui, Mohamed Amine

    2017-05-12

    In this paper, we study the achievable secrecy rate of visible light communication (VLC) links for discrete input distributions. We consider single user single eavesdropper multiple-input single-output (MISO) links. In addition, both beamforming and robust beamforming are considered. In the former case, the location of the eavesdropper is assumed to be known, whereas in the latter case, the location of the eavesdropper is unknown. We compare the obtained results with those achieved by some continuous distributions including the truncated generalized normal (TGN) distribution and the uniform distribution. We numerically show that the secrecy rate achieved by the discrete input distribution with a finite support is significantly improved as compared to those achieved by the TGN and the uniform distributions.

  7. Clicks, whistles and pulses: Passive and active signal use in dolphin communication

    Science.gov (United States)

    Herzing, Denise L.

    2014-12-01

    The search for signals out of noise is a problem not only with radio signals from the sky but in the study of animal communication. Dolphins use multiple modalities to communicate including body postures, touch, vision, and most elaborately sound. Like SETI radio signal searches, dolphin sound analysis includes the detection, recognition, analysis, and interpretation of signals. Dolphins use both passive listening and active production to communicate. Dolphins use three main types of acoustic signals: frequency modulated whistles (narrowband with harmonics), echolocation (broadband clicks) and burst pulsed sounds (packets of closely spaced broadband clicks). Dolphin sound analysis has focused on frequency-modulated whistles, yet the most commonly used signals are burst-pulsed sounds which, due to their graded and overlapping nature and bimodal inter-click interval (ICI) rates are hard to categorize. We will look at: 1) the mechanism of sound production and categories of sound types, 2) sound analysis techniques and information content, and 3) examples of lessons learned in the study of dolphin acoustics. The goal of this paper is to provide perspective on how animal communication studies might provide insight to both passive and active SETI in the larger context of searching for life signatures.

  8. A study of vocal nonlinearities in humpback whale songs: from production mechanisms to acoustic analysis

    Science.gov (United States)

    Cazau, Dorian; Adam, Olivier; Aubin, Thierry; Laitman, Jeffrey T.; Reidenberg, Joy S.

    2016-01-01

    Although mammalian vocalizations are predominantly harmonically structured, they can exhibit an acoustic complexity with nonlinear vocal sounds, including deterministic chaos and frequency jumps. Such sounds are normative events in mammalian vocalizations, and can be directly traceable to the nonlinear nature of vocal-fold dynamics underlying typical mammalian sound production. In this study, we give qualitative descriptions and quantitative analyses of nonlinearities in the song repertoire of humpback whales from the Ste Marie channel (Madagascar) to provide more insight into the potential communication functions and underlying production mechanisms of these features. A low-dimensional biomechanical modeling of the whale’s U-fold (vocal folds homolog) is used to relate specific vocal mechanisms to nonlinear vocal features. Recordings of living humpback whales were searched for occurrences of vocal nonlinearities (instabilities). Temporal distributions of nonlinearities were assessed within sound units, and between different songs. The anatomical production sources of vocal nonlinearities and the communication context of their occurrences in recordings are discussed. Our results show that vocal nonlinearities may be a communication strategy that conveys information about the whale’s body size and physical fitness, and thus may be an important component of humpback whale songs. PMID:27721476

  9. A study of vocal nonlinearities in humpback whale songs: from production mechanisms to acoustic analysis

    Science.gov (United States)

    Cazau, Dorian; Adam, Olivier; Aubin, Thierry; Laitman, Jeffrey T.; Reidenberg, Joy S.

    2016-10-01

    Although mammalian vocalizations are predominantly harmonically structured, they can exhibit an acoustic complexity with nonlinear vocal sounds, including deterministic chaos and frequency jumps. Such sounds are normative events in mammalian vocalizations, and can be directly traceable to the nonlinear nature of vocal-fold dynamics underlying typical mammalian sound production. In this study, we give qualitative descriptions and quantitative analyses of nonlinearities in the song repertoire of humpback whales from the Ste Marie channel (Madagascar) to provide more insight into the potential communication functions and underlying production mechanisms of these features. A low-dimensional biomechanical modeling of the whale’s U-fold (vocal folds homolog) is used to relate specific vocal mechanisms to nonlinear vocal features. Recordings of living humpback whales were searched for occurrences of vocal nonlinearities (instabilities). Temporal distributions of nonlinearities were assessed within sound units, and between different songs. The anatomical production sources of vocal nonlinearities and the communication context of their occurrences in recordings are discussed. Our results show that vocal nonlinearities may be a communication strategy that conveys information about the whale’s body size and physical fitness, and thus may be an important component of humpback whale songs.

  10. Digital signal processing techniques for coherent optical communication

    Science.gov (United States)

    Goldfarb, Gilad

    Coherent detection with subsequent digital signal processing (DSP) is developed, analyzed theoretically and numerically and experimentally demonstrated in various fiber-optic transmission scenarios. The use of DSP in conjunction with coherent detection unleashes the benefits of coherent detection which rely on the preservaton of full information of the incoming field. These benefits include high receiver sensitivity, the ability to achieve high spectral-efficiency and the use of advanced modulation formats. With the immense advancements in DSP speeds, many of the problems hindering the use of coherent detection in optical transmission systems have been eliminated. Most notably, DSP alleviates the need for hardware phase-locking and polarization tracking, which can now be achieved in the digital domain. The complexity previously associated with coherent detection is hence significantly diminished and coherent detection is once gain considered a feasible detection alternative. In this thesis, several aspects of coherent detection (with or without subsequent DSP) are addressed. Coherent detection is presented as a means to extend the dispersion limit of a duobinary signal using an analog decision-directed phase-lock loop. Analytical bit-error ratio estimation for quadrature phase-shift keying signals is derived. To validate the promise for high spectral efficiency, the orthogonal-wavelength-division multiplexing scheme is suggested. In this scheme the WDM channels are spaced at the symbol rate, thus achieving the spectral efficiency limit. Theory, simulation and experimental results demonstrate the feasibility of this approach. Infinite impulse response filtering is shown to be an efficient alternative to finite impulse response filtering for chromatic dispersion compensation. Theory, design considerations, simulation and experimental results relating to this topic are presented. Interaction between fiber dispersion and nonlinearity remains the last major challenge

  11. Multivariate classification of animal communication signals: a simulation-based comparison of alternative signal processing procedures using electric fishes.

    Science.gov (United States)

    Crampton, William G R; Davis, Justin K; Lovejoy, Nathan R; Pensky, Marianna

    2008-01-01

    Evolutionary studies of communication can benefit from classification procedures that allow individual animals to be assigned to groups (e.g. species) on the basis of high-dimension data representing their signals. Prior to classification, signals are usually transformed by a signal processing procedure into structural features. Applications of these signal processing procedures to animal communication have been largely restricted to the manual or semi-automated identification of landmark features from graphical representations of signals. Nonetheless, theory predicts that automated time-frequency-based digital signal processing (DSP) procedures can represent signals more efficiently (using fewer features) than can landmark procedures or frequency-based DSP - allowing more accurate classification. Moreover, DSP procedures are objective in that they require little previous knowledge of signal diversity, and are relatively free from potentially ungrounded assumptions of cross-taxon homology. Using a model data set of electric organ discharge waveforms from five sympatric species of the electric fish Gymnotus, we adopted an exhaustive simulation approach to investigate the classificatory performance of different signal processing procedures. We considered a landmark procedure, a frequency-based DSP procedure (the fast Fourier transform), and two kinds of time-frequency-based DSP procedures (a short-time Fourier transform, and several implementations of the discrete wavelet transform -DWT). The features derived from each of these signal processing procedures were then subjected to dimension reduction procedures to separate those features which permit the most effective discrimination among groups of signalers. We considered four alternative dimension reduction methods. Finally, each combination of reduced data was submitted to classification by linear discriminant analysis. Our results support theoretical predictions that time-frequency DSP procedures (especially DWT

  12. Quantum secure direct communication of digital and analog signals using continuum coherent states

    Science.gov (United States)

    Guerra, Antônio Geovan de Araújo Holanda; Rios, Francisco Franklin Sousa; Ramos, Rubens Viana

    2016-11-01

    In this work, we present optical schemes for secure direct quantum communication of digital and analog signals using continuum coherent states and frequency-dependent phase modulation. The main advantages of the proposed schemes are that they do not use entangled states and they can be implemented with today technology. The theory of quantum interference of continuum coherent state is described, and the optical setups for secure direct communication are presented and their securities are discussed.

  13. International Conference on VLSI, Communication, Advanced Devices, Signals & Systems and Networking

    CERN Document Server

    Shirur, Yasha; Prasad, Rekha

    2013-01-01

    This book is a collection of papers presented by renowned researchers, keynote speakers and academicians in the International Conference on VLSI, Communication, Analog Designs, Signals and Systems, and Networking (VCASAN-2013), organized by B.N.M. Institute of Technology, Bangalore, India during July 17-19, 2013. The book provides global trends in cutting-edge technologies in electronics and communication engineering. The content of the book is useful to engineers, researchers and academicians as well as industry professionals.

  14. Quantum secure direct communication of digital and analog signals using continuum coherent states

    Science.gov (United States)

    Guerra, Antônio Geovan de Araújo Holanda; Rios, Francisco Franklin Sousa; Ramos, Rubens Viana

    2016-08-01

    In this work, we present optical schemes for secure direct quantum communication of digital and analog signals using continuum coherent states and frequency-dependent phase modulation. The main advantages of the proposed schemes are that they do not use entangled states and they can be implemented with today technology. The theory of quantum interference of continuum coherent state is described, and the optical setups for secure direct communication are presented and their securities are discussed.

  15. Reconfigurable Signal Processing and Hardware Architecture for Broadband Wireless Communications

    Directory of Open Access Journals (Sweden)

    Liang Ying-Chang

    2005-01-01

    Full Text Available This paper proposes a broadband wireless transceiver which can be reconfigured to any type of cyclic-prefix (CP -based communication systems, including orthogonal frequency-division multiplexing (OFDM, single-carrier cyclic-prefix (SCCP system, multicarrier (MC code-division multiple access (MC-CDMA, MC direct-sequence CDMA (MC-DS-CDMA, CP-based CDMA (CP-CDMA, and CP-based direct-sequence CDMA (CP-DS-CDMA. A hardware platform is proposed and the reusable common blocks in such a transceiver are identified. The emphasis is on the equalizer design for mobile receivers. It is found that after block despreading operation, MC-DS-CDMA and CP-DS-CDMA have the same equalization blocks as OFDM and SCCP systems, respectively, therefore hardware and software sharing is possible for these systems. An attempt has also been made to map the functional reconfigurable transceiver onto the proposed hardware platform. The different functional entities which will be required to perform the reconfiguration and realize the transceiver are explained.

  16. Joint digital signal processing for superchannel coherent optical communication systems.

    Science.gov (United States)

    Liu, Cheng; Pan, Jie; Detwiler, Thomas; Stark, Andrew; Hsueh, Yu-Ting; Chang, Gee-Kung; Ralph, Stephen E

    2013-04-01

    Ultra-high-speed optical communication systems which can support ≥ 1Tb/s per channel transmission will soon be required to meet the increasing capacity demand. However, 1Tb/s over a single carrier requires either or both a high-level modulation format (i.e. 1024QAM) and a high baud rate. Alternatively, grouping a number of tightly spaced "sub-carriers" to form a terabit superchannel increases channel capacity while minimizing the need for high-level modulation formats and high baud rate, which may allow existing formats, baud rate and components to be exploited. In ideal Nyquist-WDM superchannel systems, optical subcarriers with rectangular spectra are tightly packed at a channel spacing equal to the baud rate, thus achieving the Nyquist bandwidth limit. However, in practical Nyquist-WDM systems, precise electrical or optical control of channel spectra is required to avoid strong inter-channel interference (ICI). Here, we propose and demonstrate a new "super receiver" architecture for practical Nyquist-WDM systems, which jointly detects and demodulates multiple channels simultaneously and mitigates the penalties associated with the limitations of generating ideal Nyquist-WDM spectra. Our receiver-side solution relaxes the filter requirements imposed on the transmitter. Two joint DSP algorithms are developed for linear ICI cancellation and joint carrier-phase recovery. Improved system performance is observed with both experimental and simulation data. Performance analysis under different system configurations is conducted to demonstrate the feasibility and robustness of the proposed joint DSP algorithms.

  17. Covert communications using random noise signals: effects of atmospheric propagation nulls and rain

    Science.gov (United States)

    Mohan, Karen M.; Narayanan, Ram M.

    2005-06-01

    In military communications, there exist numerous potential threats to message security. Ultra-wideband (UWB) signals provide secure communications because they cannot, in general, be detected using conventional receivers and they can be made relatively immune from jamming. The security of an UWB signal can be further improved by mixing it with random noise. By using a random noise signal, the user can conceal the message signal within the noise waveform and thwart detection by hostile forces. This paper describes a novel spread spectrum technique that can be used for secure and covert communications. The technique is based on the use of heterodyne correlation techniques to inject coherence in a random noise signal. The modulated signal to be transmitted containing the coherent carrier is mixed with a sample of an ultra-wideband (UWB) random noise signal. The frequency range of the UWB noise signal is appropriately chosen so that the lower sideband of the mixing process falls over the same frequency range. Both the frequency-converted noise-like signal and the original random noise signal are simultaneously transmitted on orthogonally polarized channels through a dual-polarized transmitting antenna. The receiver consists of a similar dual-polarized antenna that simultaneously receives the two orthogonally polarized transmitted signals, amplifies each in a minimum phase limiting amplifier, and mixes these signals in a double sideband upconverter. The upper sideband of the mixing process recovers the modulated signal, which can then be demodulated. The advantage of this technique lies in the relative immunity of the random noise-like unpolarized transmit signal from detection and jamming. Since the transmitted signal "appears" totally unpolarized and noise-like, linearly polarized receivers are unable to identify, decode, or otherwise extract useful information from the signal. The system is immune from interference caused by high power linearly polarized signal

  18. A Design of the Signal Processing Hardware Platform for Communication Systems

    Science.gov (United States)

    Lee, Byung Wook; Cho, Sung Ho

    In this letter, an efficient hardware platform for the digital signal processing for OFDM communication systems is presented. The hardware platform consists of a single FPGA having 900K gates, two DSPs with maximum 8,000 MIPS at 1GHz clock, 2-channel ADC and DAC supporting maximum 125MHz sampling rate, and flexible data bus architecture, so that a wide variety of baseband signal processing algorithms for practical OFDM communication systems may be implemented and tested. The IEEE 802.16d software modem is also presented in order to verify the effectiveness and usefulness of the designed platform.

  19. Signal measurement system for intra-body communication using optical isolation method

    Science.gov (United States)

    Matsumoto, Kazuki; Katsuyama, Jun; Sugiyama, Ryo; Takizawa, Yasuaki; Ishii, Seita; Shinagawa, Mitsuru; Kado, Yuichi

    2014-09-01

    In this paper, we describe an induced signal measurement on the human body for developing a high-performance transceiver of an intra-body communication system. It is important to isolate awearable transceiver from an electrical instrument for precise measurement. We have developed a probe system using an optical isolation method including a laser diode, photo-diode, and optical fiber. The probe system can be successfully applied to the precise measurement of a receiving signal power at a wearable transceiver. We verify that the experimental results agree with the simulation results based on our previous channel model of intra-body communication.

  20. An Overview on the Applications of Matrix Theory in Wireless Communications and Signal Processing

    Directory of Open Access Journals (Sweden)

    Xu Wang

    2016-10-01

    Full Text Available This paper overviews the key applications enabled by matrix theory in two major fields of interest in electrical engineering, namely wireless communications and signal processing. The paper focuses on the fundamental role played by matrices in modeling and optimization of wireless communication systems, and in detection, extraction and processing of the information embedded in signals. Among the major applications in wireless communications, the role of matrix representations and decompositions in characterizing multiple-input multiple-output (MIMO and orthogonal frequency division multiplexing (OFDM communication systems is described. In addition, this paper points out the important contribution made by matrices in solving signal estimation and detection problems. Special attention is given to the implementation of matrices in sensor array signal processing and the design of adaptive filters. Furthermore, the crucial role played by matrices in representing and processing digital images is depicted by several illustrative applications. This paper concludes with some applications of matrix theory in the area of compressive sensing of signals and by outlining a few open research problems for future study.

  1. Individual, unit and vocal clan level identity cues in sperm whale codas

    DEFF Research Database (Denmark)

    Gero, Shane; Whitehead, Hal; Rendell, Luke

    2016-01-01

    The ‘social complexity hypothesis’ suggests that complex social structure is a driver of diversity in animal communication systems. Sperm whales have a hierarchically structured society in which the largest affiliative structures, the vocal clans, are marked on ocean-basin scales by culturally...... transmitted dialects of acoustic signals known as ‘codas’. We examined variation in coda repertoires among both individual whales and social units—the basic element of sperm whale society—using data from nine Caribbean social units across six years. Codas were assigned to individuals using photo...

  2. Functional flexibility in wild bonobo vocal behaviour

    Directory of Open Access Journals (Sweden)

    Zanna Clay

    2015-08-01

    Full Text Available A shared principle in the evolution of language and the development of speech is the emergence of functional flexibility, the capacity of vocal signals to express a range of emotional states independently of context and biological function. Functional flexibility has recently been demonstrated in the vocalisations of pre-linguistic human infants, which has been contrasted to the functionally fixed vocal behaviour of non-human primates. Here, we revisited the presumed chasm in functional flexibility between human and non-human primate vocal behaviour, with a study on our closest living primate relatives, the bonobo (Pan paniscus. We found that wild bonobos use a specific call type (the “peep” across a range of contexts that cover the full valence range (positive-neutral-negative in much of their daily activities, including feeding, travel, rest, aggression, alarm, nesting and grooming. Peeps were produced in functionally flexible ways in some contexts, but not others. Crucially, calls did not vary acoustically between neutral and positive contexts, suggesting that recipients take pragmatic information into account to make inferences about call meaning. In comparison, peeps during negative contexts were acoustically distinct. Our data suggest that the capacity for functional flexibility has evolutionary roots that predate the evolution of human speech. We interpret this evidence as an example of an evolutionary early transition away from fixed vocal signalling towards functional flexibility.

  3. A New Feature Extraction Algorithm Based on Entropy Cloud Characteristics of Communication Signals

    Directory of Open Access Journals (Sweden)

    Jingchao Li

    2015-01-01

    Full Text Available Identifying communication signals under low SNR environment has become more difficult due to the increasingly complex communication environment. Most relevant literatures revolve around signal recognition under stable SNR, but not applicable under time-varying SNR environment. To solve this problem, we propose a new feature extraction method based on entropy cloud characteristics of communication modulation signals. The proposed algorithm extracts the Shannon entropy and index entropy characteristics of the signals first and then effectively combines the entropy theory and cloud model theory together. Compared with traditional feature extraction methods, instability distribution characteristics of the signals’ entropy characteristics can be further extracted from cloud model’s digital characteristics under low SNR environment by the proposed algorithm, which improves the signals’ recognition effects significantly. The results from the numerical simulations show that entropy cloud feature extraction algorithm can achieve better signal recognition effects, and even when the SNR is −11 dB, the signal recognition rate can still reach 100%.

  4. Chaotic signal detection and estimation based on attractor sets: applications to secure communications.

    Science.gov (United States)

    Rohde, G K; Nichols, J M; Bucholtz, F

    2008-03-01

    We consider the problem of detection and estimation of chaotic signals in the presence of white Gaussian noise. Traditionally this has been a difficult problem since generalized likelihood ratio tests are difficult to implement due to the chaotic nature of the signals of interest. Based on Poincare's recurrence theorem we derive an algorithm for approximating a chaotic time series with unknown initial conditions. The algorithm approximates signals using elements carefully chosen from a dictionary constructed based on the chaotic signal's attractor. We derive a detection approach based on the signal estimation algorithm and show, with simulated data, that the new approach can outperform other methods for chaotic signal detection. Finally, we describe how the attractor based detection scheme can be used in a secure binary digital communications protocol.

  5. Chaotic signal detection and estimation based on attractor sets: Applications to secure communications

    Science.gov (United States)

    Rohde, G. K.; Nichols, J. M.; Bucholtz, F.

    2008-03-01

    We consider the problem of detection and estimation of chaotic signals in the presence of white Gaussian noise. Traditionally this has been a difficult problem since generalized likelihood ratio tests are difficult to implement due to the chaotic nature of the signals of interest. Based on Poincare's recurrence theorem we derive an algorithm for approximating a chaotic time series with unknown initial conditions. The algorithm approximates signals using elements carefully chosen from a dictionary constructed based on the chaotic signal's attractor. We derive a detection approach based on the signal estimation algorithm and show, with simulated data, that the new approach can outperform other methods for chaotic signal detection. Finally, we describe how the attractor based detection scheme can be used in a secure binary digital communications protocol.

  6. Vocal mechanisms in birds and bats: a comparative view

    Directory of Open Access Journals (Sweden)

    Suthers Roderick A.

    2004-01-01

    Full Text Available Vocal signals play a very important role in the life of both birds and echolocating bats, but these two unrelated groups of flying vertebrates have very different vocal systems. They nevertheless must solve many of the same problems in producing sound. This brief review examines avian and microchiropteran motor mechanisms for: 1 coordinating the timing of phonation with the vocal motor pattern that controls its acoustic properties, and 2 achieving respiratory strategies that provide adequate ventilation for pulmonary gas exchange, while also facilitating longer duration songs or trains of sonar pulses.

  7. Vocal copying of individually distinctive signature whistles in bottlenose dolphins

    Science.gov (United States)

    King, Stephanie L.; Sayigh, Laela S.; Wells, Randall S.; Fellner, Wendi; Janik, Vincent M.

    2013-01-01

    Vocal learning is relatively common in birds but less so in mammals. Sexual selection and individual or group recognition have been identified as major forces in its evolution. While important in the development of vocal displays, vocal learning also allows signal copying in social interactions. Such copying can function in addressing or labelling selected conspecifics. Most examples of addressing in non-humans come from bird song, where matching occurs in an aggressive context. However, in other animals, addressing with learned signals is very much an affiliative signal. We studied the function of vocal copying in a mammal that shows vocal learning as well as complex cognitive and social behaviour, the bottlenose dolphin (Tursiops truncatus). Copying occurred almost exclusively between close associates such as mother–calf pairs and male alliances during separation and was not followed by aggression. All copies were clearly recognizable as such because copiers consistently modified some acoustic parameters of a signal when copying it. We found no evidence for the use of copying in aggression or deception. This use of vocal copying is similar to its use in human language, where the maintenance of social bonds appears to be more important than the immediate defence of resources. PMID:23427174

  8. Expedience of application of MIMO systems of digital communication for complex chaotic signal transmission

    OpenAIRE

    Vasyuta, K. S.; Zakharchenko, I. V.; Ozerov, S. V.

    2015-01-01

    The paper discusses the expediency of using MIMO digital systems for transmission of chaotic signals as a way of partial solution of electromagnetic compatibility of perspective broadband communication systems with an existing class of narrow-band radio-technical systems.

  9. Substrate-borne vibrational signals in intraspecific communication of glassy-winged sharpshooters (GWSS)

    Science.gov (United States)

    Exploitation of vibrational signals for suppressing glassy-winged sharpshooter (GWSS) populations could prove to be a useful tool. However, existing knowledge on GWSS vibrational communication is insufficient to implement a management program for this pest in California. Therefore, the objective of ...

  10. 传播学视野下的中国民族声乐价值现状与发展对策研究%A Study of the Current Situation of Chinese National Vocal Music and the Coping Strategies for Development. A Perspective of Communication

    Institute of Scientific and Technical Information of China (English)

    伊丽媛

    2011-01-01

    From a perspective of communication studies, the theory of two-step communication contributes to the acceptance of Chinese national vocal music by more people. And the agenda setting theory can lay a solid mass foundation of Chinese national vocal music. Moreover, the inheritance nature of communication concept provides the guarantee for the highlight and innovation of national vocal music. To drive the development of the national vocal music with the application of communication theories, we should pay more attention to the disseminating function of news conference and mass media. In addition, we should make great efforts to do well the work of inheriting and developing our national music. Further, we should dare to give up old and unitary conceptions and take more roads to our development.%在传播学视野下,“二级传播”理论使得中国民族声乐被更多人所接受;“议程设置”理论为中国民族声乐奠定更为牢固的群众基础;传播学理念的“传承特性”,为弘扬与创新民族声乐艺术,提供了根本性保障。运用传播学理论促进中国民族声乐科学发展,应注重借助新闻发布会的组织传播功效积极造势;注重发挥大众传媒强大的传播功能;要努力做好中国民族声乐文化继承与发展这篇大文章;要敢于破除陈旧观念,摒弃单一化,走多元化发展之路。

  11. Vocal Fold Collision Modeling

    DEFF Research Database (Denmark)

    Granados, Alba; Brunskog, Jonas; Misztal, M. K.

    2015-01-01

    When vocal folds vibrate at normal speaking frequencies, collisions occurs. The numerics and formulations behind a position-based continuum model of contact is an active field of research in the contact mechanics community. In this paper, a frictionless three-dimensional finite element model...... of the vocal fold collision is proposed, which incorporates different procedures used in contact mechanics and mathematical optimization theories. The penalty approach and the Lagrange multiplier method are investigated. The contact force solution obtained by the penalty formulation is highly dependent...

  12. Reconstruction of chaotic signals with applications to chaos-based communications

    CERN Document Server

    Feng, Jiu Chao

    2008-01-01

    This book provides a systematic review of the fundamental theory of signal reconstruction and the practical techniques used in reconstructing chaotic signals. Specific applications of signal reconstruction methods in chaos-based communications are expounded in full detail, along with examples illustrating the various problems associated with such applications.The book serves as an advanced textbook for undergraduate and graduate courses in electronic and information engineering, automatic control, physics and applied mathematics. It is also highly suited for general nonlinear scientists who wi

  13. Communicative Signals Promote Object Recognition Memory and Modulate the Right Posterior STS.

    Science.gov (United States)

    Redcay, Elizabeth; Ludlum, Ruth S; Velnoskey, Kayla R; Kanwal, Simren

    2016-01-01

    Detection of communicative signals is thought to facilitate knowledge acquisition early in life, but less is known about the role these signals play in adult learning or about the brain systems supporting sensitivity to communicative intent. The current study examined how ostensive gaze cues and communicative actions affect adult recognition memory and modulate neural activity as measured by fMRI. For both the behavioral and fMRI experiments, participants viewed a series of videos of an actress acting on one of two objects in front of her. Communicative context in the videos was manipulated in a 2 × 2 design in which the actress either had direct gaze (Gaze) or wore a visor (NoGaze) and either pointed at (Point) or reached for (Reach) one of the objects (target) in front of her. Participants then completed a recognition memory task with old (target and nontarget) objects and novel objects. Recognition memory for target objects in the Gaze conditions was greater than NoGaze, but no effects of gesture type were seen. Similarly, the fMRI video-viewing task revealed a significant effect of Gaze within right posterior STS (pSTS), but no significant effects of Gesture. Furthermore, pSTS sensitivity to Gaze conditions was related to greater memory for objects viewed in Gaze, as compared with NoGaze, conditions. Taken together, these results demonstrate that the ostensive, communicative signal of direct gaze preceding an object-directed action enhances recognition memory for attended items and modulates the pSTS response to object-directed actions. Thus, establishment of a communicative context through ostensive signals remains an important component of learning and memory into adulthood, and the pSTS may play a role in facilitating this type of social learning.

  14. Differential expression of glutamate receptors in avian neural pathways for learned vocalization.

    Science.gov (United States)

    Wada, Kazuhiro; Sakaguchi, Hironobu; Jarvis, Erich D; Hagiwara, Masatoshi

    2004-08-01

    that neural activity and signal transduction in vocal nuclei of vocal learners will be different relative to the surrounding brain areas.

  15. A secure communication method for a high-power information signal based on chaotic masking

    Institute of Scientific and Technical Information of China (English)

    李建芬; 李农

    2002-01-01

    In this paper, we present a secure communication method for a high-power information signal based on chaoticmasking. In the transmitter, an adaptive controller is adopted to pick up the change of the information signal, andto inject the controller's error into the transmitting system. At the same time, the information is directly added tothe chaotic signal in transmission to drive the receiving system. In the receiver, another adaptive controller is usedto maintain chaotic synchronization of the transmitting and receiving systems and to recover the information signal.Since the synchronization error is independent from the information signal, the power of the information signal can beequivalent to that of the chaotic signal, and the frequency of the information signal can be set within the range of theprincipal frequencies of the chaotic signal. The results of theoretical analysis and numerical simulation show that thepresented method not only enhances the degree of security of low-dimensional chaotic systems but also significantlyimproves the signal-to-noise ratio at the receiving end.

  16. The vocal repertoire of adult and neonate giant otters (Pteronura brasiliensis.

    Directory of Open Access Journals (Sweden)

    Christina A S Mumm

    Full Text Available Animals use vocalizations to exchange information about external events, their own physical or motivational state, or about individuality and social affiliation. Infant babbling can enhance the development of the full adult vocal repertoire by providing ample opportunity for practice. Giant otters are very social and frequently vocalizing animals. They live in highly cohesive groups, generally including a reproductive pair and their offspring born in different years. This basic social structure may vary in the degree of relatedness of the group members. Individuals engage in shared group activities and different social roles and thus, the social organization of giant otters provides a basis for complex and long-term individual relationships. We recorded and analysed the vocalizations of adult and neonate giant otters from wild and captive groups. We classified the adult vocalizations according to their acoustic structure, and described their main behavioural context. Additionally, we present the first description of vocalizations uttered in babbling bouts of new born giant otters. We expected to find 1 a sophisticated vocal repertoire that would reflect the species' complex social organisation, 2 that giant otter vocalizations have a clear relationship between signal structure and function, and 3 that the vocal repertoire of new born giant otters would comprise age-specific vocalizations as well as precursors of the adult repertoire. We found a vocal repertoire with 22 distinct vocalization types produced by adults and 11 vocalization types within the babbling bouts of the neonates. A comparison within the otter subfamily suggests a relation between vocal and social complexity, with the giant otters being the socially and vocally most complex species.

  17. Method and apparatus for a single channel digital communications system. [synchronization of received PCM signal by digital correlation with reference signal

    Science.gov (United States)

    Couvillon, L. A., Jr.; Carl, C.; Goldstein, R. M.; Posner, E. C.; Green, R. R. (Inventor)

    1973-01-01

    A method and apparatus are described for synchronizing a received PCM communications signal without requiring a separate synchronizing channel. The technique provides digital correlation of the received signal with a reference signal, first with its unmodulated subcarrier and then with a bit sync code modulated subcarrier, where the code sequence length is equal in duration to each data bit.

  18. Modal locking between vocal fold and vocal tract oscillations: Simulations in time domain

    CERN Document Server

    Aalto, Atte; Malinen, Jarmo; Aalto, Daniel; Vainio, Martti

    2015-01-01

    It is well known that during voiced speech, the human vocal folds interact with the vocal tract acoustics. The resulting source-filter coupling has been observed using mathematical and physical models as well as in in vivo phonation. We propose a computational time-domain model of the full speech apparatus that, in particular, contains a feedback mechanism from the vocal tract acoustics to the vocal fold oscillations. It is based on numerical solution of ordinary and partial differential equations defined on vocal tract geometries that have been obtained by Magnetic Resonance Imaging. The model is used to simulate rising and falling pitch glides of [a, i] in the fundamental frequency (f_0) interval [180 Hz, 360 Hz]. The interval contains the first formant F1 of [i] as well as the subformants F1/4 and F1/3 of [a]. The simulations reveal a locking pattern of the f_0-trajectory at F1 of [i] in falling and rising glides. The subformants of [a] produce perturbations in the waveforms of glottal signals but no locki...

  19. Fractal Communication System Using Digital Signal Processing Starter Kit (DSK TMS320c6713

    Directory of Open Access Journals (Sweden)

    Arsyad Ramadhan Darlis

    2015-12-01

    Full Text Available In 1992, Wornell and Oppenheim did research on a modulation which is formed by using wavelet theory. In some other studies, proved that this modulation can survive on a few channels and has reliability in some applications. Because of this modulation using the concept of fractal, then it is called as fractalmodulation. Fractal modulation is formed by inserting information signal into fractal signals that are selffractal similary. This modulation technique has the potential to replace the OFDM (Orthogonal Frequency Division Multiplexing, which is currently used on some of the latest telecommunication technologies. The purpose of this research is to implement the fractal communication system using Digital Signal Processing Starter Kit (DSK TMS320C6713 without using AWGN and Rayleigh channel in order to obtain the ideal performance of the system. From the simulation results using MATLAB7.4. it appears that this communication system has good performance on some channels than any other communication systems. While in terms of implementation by using (DSK via TMS320C6713 Code Composer Studio (CCS, it can be concluded that thefractal communication system has a better execution time on some tests.

  20. A nomenclature paradigm for benign midmembranous vocal fold lesions.

    Science.gov (United States)

    Rosen, Clark A; Gartner-Schmidt, Jackie; Hathaway, Bridget; Simpson, C Blake; Postma, Gregory N; Courey, Mark; Sataloff, Robert T

    2012-06-01

    There is a significant lack of uniform agreement regarding nomenclature for benign vocal fold lesions (BVFLs). This confusion results in difficulty for clinicians communicating with their patients and with each other. In addition, BVFL research and comparison of treatment methods are hampered by the lack of a detailed and uniform BVFL nomenclature. Clinical consensus conferences were held to develop an initial BVFL nomenclature paradigm. Perceptual video analysis was performed to validate the stroboscopy component of the paradigm. The culmination of the consensus conferences and the video-perceptual analysis was used to evaluate the BVFL nomenclature paradigm using a retrospective review of patients with BVFL. An initial BVFL nomenclature paradigm was proposed utilizing detailed definitions relating to vocal fold lesion morphology, stroboscopy, response to voice therapy and intraoperative findings. Video-perceptual analysis of stroboscopy demonstrated that the proposed binary stroboscopy system used in the BVFL nomenclature paradigm was valid and widely applicable. Retrospective review of 45 patients with BVFL followed to the conclusion of treatment demonstrated that slight modifications of the initial BVFL nomenclature paradigm were required. With the modified BVFL nomenclature paradigm, 96% of the patients fit into the predicted pattern and definitions of the BVFL nomenclature system. This study has validated a multidimensional BVFL nomenclature paradigm. This vocal fold nomenclature paradigm includes nine distinct vocal fold lesions: vocal fold nodules, vocal fold polyp, pseudocyst, vocal fold cyst (subepithelial or ligament), nonspecific vocal fold lesion, vocal fold fibrous mass (subepithelial or ligament), and reactive lesion. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

  1. Signaling in a polluted world: oxidative stress as an overlooked mechanism linking contaminants to animal communication

    Directory of Open Access Journals (Sweden)

    Valeria Marasco

    2016-08-01

    Full Text Available The capacity to communicate effectively with other individuals plays a critical role in the daily life of an individual and can have important fitness consequences. Animals rely on a number of visual and non-visual signals, whose production brings costs to the individual. The theory of honest signaling states that these costs are higher for low than for high-quality individuals, which prevents cheating and makes signals, such as skin and plumage colouration, indicators of individual’s quality or condition. The condition-dependent nature of signals makes them ideally suited as indicators of environmental quality, implying that signal production might be affected by contaminants. In this mini-review article, we have made the point that oxidative stress (OS is one overlooked mechanism linking exposure to contaminants to signaling because (i many contaminants can influence the individual’s oxidative balance, and (ii generation of both visual and non-visual signals is sensitive to oxidative stress. To this end, we have provided the first comprehensive review on the way both non-organic (heavy metals, especially mercury and organic (persistent organic pollutants contaminants may influence either OS or sexual signaling. We have also paid special attention to emerging classes of pollutants like brominated flame-retardants and perfluoroalkoxy alkanes in order to stimulate research in this area. We have finally provided suggestions and warnings for future work on the links among OS, sexual signaling and contaminant exposure.

  2. Communication efficiency and congestion of signal traffic in large-scale brain networks.

    Science.gov (United States)

    Mišić, Bratislav; Sporns, Olaf; McIntosh, Anthony R

    2014-01-01

    The complex connectivity of the cerebral cortex suggests that inter-regional communication is a primary function. Using computational modeling, we show that anatomical connectivity may be a major determinant for global information flow in brain networks. A macaque brain network was implemented as a communication network in which signal units flowed between grey matter nodes along white matter paths. Compared to degree-matched surrogate networks, information flow on the macaque brain network was characterized by higher loss rates, faster transit times and lower throughput, suggesting that neural connectivity may be optimized for speed rather than fidelity. Much of global communication was mediated by a "rich club" of hub regions: a sub-graph comprised of high-degree nodes that are more densely interconnected with each other than predicted by chance. First, macaque communication patterns most closely resembled those observed for a synthetic rich club network, but were less similar to those seen in a synthetic small world network, suggesting that the former is a more fundamental feature of brain network topology. Second, rich club regions attracted the most signal traffic and likewise, connections between rich club regions carried more traffic than connections between non-rich club regions. Third, a number of rich club regions were significantly under-congested, suggesting that macaque connectivity actively shapes information flow, funneling traffic towards some nodes and away from others. Together, our results indicate a critical role of the rich club of hub nodes in dynamic aspects of global brain communication.

  3. Optical techniques for signal distribution and control in advanced radar and communication systems

    Science.gov (United States)

    Forrest, J. R.

    1985-03-01

    It is concluded that optical techniques offer some advantages for signal distribution and control in advanced radar and communication systems. They are clearly ideal for transporting microwave signals over considerable distances, as in remote positioning of radar receivers, provided high dynamic range is not required and an enclosed transmission path is essential. They are an elegant means of distributing low level r.f. or i.f. signals around an active phased array where these signals are of relatively constant amplitude (as in mixer local oscillator applications). However, there is currently a rather restrictive limit on the size of distribution network possible. Optical techniques are obviously suitable for distributing digital control signals to phased array modules and confer considerable immunity to interference. They are less suitable for high dynamic range signals, such as the received radar returns, either at r.f. or when downcovered to i.f. Future developments in coherent optics or in fast optical A/D technology could, however, influence this conclusion. Currently, the optimum applications for optical techniques appear to be i.f. beamformers for multibeam communication satellite systems and in calibration/monitoring systems for phased arrays.

  4. Intelligent Advanced Communications IP Telephony Feasibility for the U.S. Navy. Volume 1

    Science.gov (United States)

    2007-10-01

    the vocal tract and the vibration of the vocal chord . If the model of the vocal tract and its vibrations is good, then the error between the actual...from Department of Computer Science at the Columbia University, University of Maryland Advanced Computer Studies, Cisco Systems Inc., and Vocal ...for several open source VoIP software packages, with a special focus of VOCAL , Vovida’s own open communication application library. While VOCAL is the

  5. Audience affects decision-making in a marmoset communication network.

    Science.gov (United States)

    Toarmino, Camille R; Wong, Lauren; Miller, Cory T

    2017-01-01

    An audience can have a profound effect on the dynamics of communicative interactions. As a result, non-human primates often adjust their social decision-making strategies depending on the audience composition at a given time. Here we sought to test how the unique vocal behaviour of multiple audience members affected decisions to communicate. To address this issue, we developed a novel experimental paradigm in which common marmosets directly interacted with multiple 'virtual monkeys' (VMs), each of whom represented an individual marmoset with distinct vocal behaviour. This active social signalling paradigm provided subjects an opportunity to interact with and learn about the behaviour of each VM in the network and apply this knowledge in subsequent communicative decisions. We found that subjects' propensity to interact with particular VMs was determined by the behaviour of each VM in the audience and suggests that marmoset social decision-making strategies are highly adaptive to nuances of the immediate communication network.

  6. Probability and Random Processes With Applications to Signal Processing and Communications

    CERN Document Server

    Miller, Scott

    2012-01-01

    Miller and Childers have focused on creating a clear presentation of foundational concepts with specific applications to signal processing and communications, clearly the two areas of most interest to students and instructors in this course. It is aimed at graduate students as well as practicing engineers, and includes unique chapters on narrowband random processes and simulation techniques. The appendices provide a refresher in such areas as linear algebra, set theory, random variables, and more. Probability and Random Processes also includes applications in digital communications, informati

  7. To signal or not to signal? Chemical communication by urine-borne signals mirrors sexual conflict in crayfish

    Directory of Open Access Journals (Sweden)

    Breithaupt Thomas

    2010-03-01

    Full Text Available Abstract Background Sexual selection theory predicts that females, being the limiting sex, invest less in courtship signals than males. However, when chemical signals are involved it is often the female that initiates mating by producing stimuli that inform about sex and/or receptivity. This apparent contradiction has been discussed in the literature as 'the female pheromone fallacy'. Because the release of chemical stimuli may not have evolved to elicit the male's courtship response, whether these female stimuli represent signals remains an open question. Using techniques to visualise and block release of urine, we studied the role of urine signals during fighting and mating interactions of crayfish (Pacifastacus leniusculus. Test individuals were blindfolded to exclude visual disturbance from dye release and artificial urine introduction. Results Staged female-male pairings during the reproductive season often resulted in male mating attempts. Blocking female urine release in such pairings prevented any male courtship behaviour. Artificial introduction of female urine re-established male mating attempts. Urine visualisation showed that female urine release coincides with aggressive behaviours but not with female submissive behaviour in reproductive interactions as well as in intersexual and intrasexual fights. In reproductive interactions, females predominately released urine during precopulatory aggression; males subsequently released significantly less urine during mating than in fights. Conclusions Urine-blocking experiments demonstrate that female urine contains sex-specific components that elicit male mating behaviour. The coincidence of chemical signalling and aggressive behaviour in both females and males suggests that urine release has evolved as an aggressive signal in both sexes of crayfish. By limiting urine release to aggressive behaviours in reproductive interactions females challenge their potential mating partners at the same

  8. Biochar and microbial signaling: production conditions determine effects on microbial communication

    Science.gov (United States)

    Masiello, Caroline A.; Chen, Ye; Gao, Xiaodong; Liu, Shirley; Cheng, Hsiao-Ying; Bennett, Matthew R.; Rudgers, Jennifer A.; Wagner, Daniel S.; Zygourakis, Kyriacos; Silberg, Jonathan J.

    2013-01-01

    Charcoal has a long soil residence time, which has resulted in its production and use as a carbon sequestration technique (biochar). A range of biological effects can be triggered by soil biochar that can positively and negatively influence carbon storage, such as changing the decomposition rate of organic matter and altering plant biomass production. Sorption of cellular signals has been hypothesized to underlie some of these effects, but it remains unknown whether the binding of biochemical signals occurs, and if so, on time scales relevant to microbial growth and communication. We examined biochar sorption of N-3-oxo-dodecanoyl-L-homoserine lactone, an acyl-homoserine lactone (AHL) intercellular signaling molecule used by many gram-negative soil microbes to regulate gene expression. We show that wood biochars disrupt communication within a growing multicellular system that is made up of sender cells that synthesize AHL and receiver cells that express green fluorescent protein in response to an AHL signal. However, biochar inhibition of AHL-mediated cell-cell communication varied, with the biochar prepared at 700°C (surface area of 301 m2/g) inhibiting cellular communication 10-fold more than an equivalent mass of biochar prepared at 300°C (surface area of 3 m2/g). These findings provide the first direct evidence that biochars elicit a range of effects on gene expression dependent on intercellular signaling, implicating the method of biochar preparation as a parameter that could be tuned to regulate microbial-dependent soil processes, like nitrogen fixation and pest attack of root crops. PMID:24066613

  9. Vocal Learning in Grey Parrots: A Brief Review of Perception, Production, and Cross-Species Comparisons

    Science.gov (United States)

    Pepperberg, Irene M.

    2010-01-01

    This chapter briefly reviews what is known-and what remains to be understood--about Grey parrot vocal learning. I review Greys' physical capacities--issues of auditory perception and production--then discuss how these capacities are used in vocal learning and can be recruited for referential communication with humans. I discuss cross-species…

  10. Mice produce ultrasonic vocalizations by intra-laryngeal planar impinging jets

    DEFF Research Database (Denmark)

    Mahrt, Elena; Agarwal, Anurag; Perkel, David

    2016-01-01

    and experimental evidence for an alternative and novel vocal production mechanism: a glottal jet impinging onto the laryngeal inner planar wall. Our data provide a framework for future research on the neuromuscular control of mouse vocal production and for interpreting mouse vocal behavior phenotypes.......Rodent ultrasonic vocalizations (USVs) are a vital tool for linking gene mutations to behavior in mouse models of communication disorders, such as autism [1]. However, we currently lack an understanding of how physiological and physical mechanisms combine to generate acoustic features...

  11. Design of two-dimensional signal constellations for visible light communication

    Science.gov (United States)

    Huang, Nuo; Wang, Jun-Bo; Zheng, Beixiong; Guan, Rui; Chen, Ming

    2017-02-01

    This paper investigates a two-dimensional signal space for visible light communication (VLC) by taking into account some practical constraints. We first present the relationship between the signal space and basis functions, and then find the basis function yielding the largest signal space. Besides, to improve the symbol error rate (SER) performance of the system, we design the constellations by maximizing the minimum Euclidean distance among all constellation pairs. The original optimization problem is non-convex and relaxed to a convex one through a linear approximation method. Simulation results show that the optimized design provides significant signal-to-noise ratio gain (up to 6 dB at the SER of 10-4 for half-illumination target) over the heuristic design.

  12. An Extraction Method of Weak Low-Frequency Magnetic Communication Signals Based on Multisensor

    Directory of Open Access Journals (Sweden)

    Chao Huang

    2015-01-01

    Full Text Available It is a technical challenge to effectively remove the influence of magnetic noise from the vicinity of the receiving sensors on low-frequency magnetic communication. The traditional denoising methods are difficult to extract high-quality original signals under the condition of low SNR (the signal-to-noise ratio. In this paper, we analyze the numerical characteristics of the low-frequency magnetic field and propose the algorithms of the fast optimization of blind source separation (FOBSS and the frequency-domain correlation extraction (FDCE. FOBSS is based on blind source separation (BSS. Signal extraction of low SNR can be implemented through FOBSS and FDCE. This signal extraction method is verified in multiple field experiments which can remove the magnetic noise by about 25 dB or more.

  13. When ambient noise impairs parent-offspring communication.

    Science.gov (United States)

    Lucass, Carsten; Eens, Marcel; Müller, Wendt

    2016-05-01

    Ambient noise has increased in extent, duration and intensity with significant implications for species' lives. Birds especially, because they heavily rely on vocal communication, are highly sensitive towards noise pollution. Noise can impair the quality of a territory or hamper the transmission of vocal signals such as song. The latter has significant fitness consequences as it may erode partner preferences in the context of mate choice. Additional fitness costs may arise if noise masks communication between soliciting offspring and providing parents during the period of parental care. Here, we experimentally manipulated the acoustic environment of blue tit (Cyanistes caeruleus) families within their nest boxes with playbacks of previously recorded highway noise and investigated the consequences on parent-offspring communication. We hypothesized that noise interferes with the acoustic cues of parental arrival and vocal components of offspring begging. As such we expected an increase in the frequency of missed detections, when nestlings fail to respond to the returning parent, and a decrease in parental provisioning rates. Parents significantly reduced their rate of provisioning in noisy conditions compared to a control treatment. This reduction is likely to be the consequence of a parental misinterpretation of the offspring hunger level, as we found that nestlings fail to respond to the returning parent more frequently in the presence of noise. Noise also potentially masks vocal begging components, again contributing to parental underestimation of offspring requirements. Either way, it appears that noise impaired parent-offspring communication is likely to reduce reproductive success.

  14. Long-Distance Communication and Signal Amplification in Systemic Acquired Resistance

    Directory of Open Access Journals (Sweden)

    Jyoti eShah

    2013-02-01

    Full Text Available Systemic acquired resistance (SAR is an inducible defense mechanism in plants that confers enhanced resistance against a variety of pathogens. SAR is activated in the uninfected systemic (distal organs in response to a prior (primary infection elsewhere in the plant. SAR is associated with the activation of salicylic acid (SA signaling and the priming of defense responses for robust activation in response to subsequent infections. The activation of SAR requires communication by the primary infected tissues with the distal organs. The vasculature functions as a conduit for the translocation of factors that facilitate long-distance intra-plant communication. In recent years, several metabolites putatively involved in long-distance signaling have been identified. These include the methyl ester of SA (MeSA, the abietane diterpenoid dehydroabietinal (DA, the dicarboxylic acid azelaic acid (AzA, and a glycerol-3-phosphate (G3P-dependent factor. Long-distance signaling by some of these metabolites also requires the lipid-transfer protein DIR1 (DEFECTIVE IN INDUCED RESISTANCE 1. The relative contribution of these factors in long-distance signaling is likely influenced by environmental conditions, for example light. In the systemic leaves, the AGD2-LIKE DEFENSE RESPONSE PROTEIN1 (ALD1-dependent production of the lysine catabolite pipecolic acid (Pip, FLAVIN-DEPENDENT MONOOXYGENASE1 (FMO1 signaling, as well as SA synthesis and downstream signaling are required for the activation of SAR. This review summarizes the involvement and interaction between long-distance SAR signals and details the recently discovered role of Pip in defense amplification and priming that allows plants to acquire immunity at the systemic level. Recent advances in SA signaling and perception are also highlighted.

  15. A Simple Semaphore Signaling Technique for Ultra-High Frequency Spacecraft Communications

    Science.gov (United States)

    Butman, S.; Satorius, E.; Ilott, P.

    2005-01-01

    For planetary lander missions such as the upcoming Phoenix mission to Mars, the most challenging phase of the spacecraft-to-ground communications is during the critical phase termed entry, descent, and landing (EDL). At 8.4 GHz (X-band), the signals received by the largest Deep Space Network (DSN) antennas can be too weak for even 1 bit per second (bps) and therefore not able to communicate critical information to Earth. Fortunately, the lander s ultra-high frequency (UHF) link to an orbiting relay can meet the EDL requirements, but the data rate needs to be low enough to fit the capability of the UHF link during some or all of EDL. On Phoenix, the minimum data rate of the as-built UHF radio is 8 kbps and requires a signal level at the Odyssey orbiter of at least -120 dBm. For lower signaling levels, the effective data rate needs to be reduced, but without incurring the cost of rebuilding and requalifying the equipment. To address this scenario, a simple form of frequency-shift keying (FSK) has been devised by appropriately programming the data stream that is input to the UHF transceiver. This article describes this technique and provides performance estimates. Laboratory testing reveals that input signal levels at -140 dBm and lower can routinely be demodulated with the proposed signaling scheme, thereby providing a 20-dB and greater margin over the 8-kbps threshold.

  16. Modulation Classification of Satellite Communication Signals Using Cumulants and Neural Networks

    Science.gov (United States)

    Smith, Aaron; Evans, Michael; Downey, Joseph

    2017-01-01

    National Aeronautics and Space Administration (NASA)'s future communication architecture is evaluating cognitive technologies and increased system intelligence. These technologies are expected to reduce the operational complexity of the network, increase science data return, and reduce interference to self and others. In order to increase situational awareness, signal classification algorithms could be applied to identify users and distinguish sources of interference. A significant amount of previous work has been done in the area of automatic signal classification for military and commercial applications. As a preliminary step, we seek to develop a system with the ability to discern signals typically encountered in satellite communication. Proposed is an automatic modulation classifier which utilizes higher order statistics (cumulants) and an estimate of the signal-to-noise ratio. These features are extracted from baseband symbols and then processed by a neural network for classification. The modulation types considered are phase-shift keying (PSK), amplitude and phase-shift keying (APSK),and quadrature amplitude modulation (QAM). Physical layer properties specific to the Digital Video Broadcasting - Satellite- Second Generation (DVB-S2) standard, such as pilots and variable ring ratios, are also considered. This paper will provide simulation results of a candidate modulation classifier, and performance will be evaluated over a range of signal-to-noise ratios, frequency offsets, and nonlinear amplifier distortions.

  17. Characterizing Chilean blue whale vocalizations with DTAGs: a test of using tag accelerometers for caller identification.

    Science.gov (United States)

    Saddler, Mark R; Bocconcelli, Alessandro; Hickmott, Leigh S; Chiang, Gustavo; Landea-Briones, Rafaela; Bahamonde, Paulina A; Howes, Gloria; Segre, Paolo S; Sayigh, Laela S

    2017-09-07

    Vocal behavior of blue whales (Balaenoptera musculus) in the Gulf of Corcovado, Chile, was analyzed using both audio and accelerometer data from digital acoustic recording tags (DTAGs). Over the course of three austral summers (2014, 2015, 2016), seventeen tags were deployed, yielding 124 hours of data. We report the occurrence of Southeast Pacific type 2 (SEP2) calls, which exhibit peak frequencies, durations, and timing consistent with previous recordings made using towed and moored hydrophones. We also describe tonal downswept (D) calls, which have not been previously described for this population. Since being able to accurately assign vocalizations to individual whales is fundamental for studying communication and for estimating population densities from call rates, we further examine the feasibility of using high-resolution DTAG accelerometers to identify low-frequency calls produced by tagged blue whales. We cross-correlated acoustic signals with simultaneous tri-axial accelerometer readings in order to analyze the phase match as well as the amplitude of accelerometer signals associated with low-frequency calls, which provides a quantitative method of determining if a call is associated with a detectable acceleration signal. Our results suggest that vocalizations from nearby individuals are also capable of registering accelerometer signals in the tagged whale's DTAG record. We cross-correlate acceleration vectors between calls to explore the possibility of using signature acceleration patterns associated with sounds produced within the tagged whale as a new method of identifying which accelerometer-detectable calls originate from the tagged animal. © 2017. Published by The Company of Biologists Ltd.

  18. Data-derived symbol synchronization of MASK and QASK signals. [for multilevel digital communication systems

    Science.gov (United States)

    Simon, M. K.

    1974-01-01

    Multilevel amplitude-shift-keying (MASK) and quadrature amplitude-shift-keying (QASK) as signaling techniques for multilevel digital communications systems, and the problem of providing symbol synchronization in the receivers of such systems are discussed. A technique is presented for extracting symbol sync from an MASK or QASK signal. The scheme is a generalization of the data transition tracking loop used in PSK systems. The performance of the loop was analyzed in terms of its mean-squared jitter and its effects on the data detection process in MASK and QASK systems.

  19. Satellite Microwave Communication Signal Degradation Due To Hall Thruster Plasma Plumes

    Science.gov (United States)

    Wiley, J. C.; Hallock, G. A.; Spencer, E. A.; Meyer, J. W.; Loane, J. T.

    2001-10-01

    We have developed a geometric optics vector ray-tracing code, BeamServer, for analyzing the effects of Hall thruster plasma plumes on satellite microwave communication signals. The possible effects include main beam attenuation and squinting, side lobe degradation, and induced cross-polarization. We report on a study of Hall current thruster (HCT) mounting positions on a realistic satellite configuration and a study with a highly shaped reflector. Results indicate HCT signal degradation can occur and should be considered in the satellite design process. Initial results of antenna pattern perturbations due to low frequency plume oscillations driven by thruster instabilities are also given.

  20. Phylogenetic comparative analysis of electric communication signals in ghost knifefishes (Gymnotiformes: Apteronotidae).

    Science.gov (United States)

    Turner, Cameron R; Derylo, Maksymilian; de Santana, C David; Alves-Gomes, José A; Smith, G Troy

    2007-12-01

    Electrocommunication signals in electric fish are diverse, easily recorded and have well-characterized neural control. Two signal features, the frequency and waveform of the electric organ discharge (EOD), vary widely across species. Modulations of the EOD (i.e. chirps and gradual frequency rises) also function as active communication signals during social interactions, but they have been studied in relatively few species. We compared the electrocommunication signals of 13 species in the largest gymnotiform family, Apteronotidae. Playback stimuli were used to elicit chirps and rises. We analyzed EOD frequency and waveform and the production and structure of chirps and rises. Species diversity in these signals was characterized with discriminant function analyses, and correlations between signal parameters were tested with phylogenetic comparative methods. Signals varied markedly across species and even between congeners and populations of the same species. Chirps and EODs were particularly evolutionarily labile, whereas rises differed little across species. Although all chirp parameters contributed to species differences in these signals, chirp amplitude modulation, frequency modulation (FM) and duration were particularly diverse. Within this diversity, however, interspecific correlations between chirp parameters suggest that mechanistic trade-offs may shape some aspects of signal evolution. In particular, a consistent trade-off between FM and EOD amplitude during chirps is likely to have influenced the evolution of chirp structure. These patterns suggest that functional or mechanistic linkages between signal parameters (e.g. the inability of electromotor neurons increase their firing rates without a loss of synchrony or amplitude of action potentials) constrain the evolution of signal structure.

  1. From communication signals to human language and thought: evolution or revolution?

    Science.gov (United States)

    Chernigovskaya, T V

    2009-10-01

    This article addresses a question which has in recent years been widely discussed: that of the specific features of mental functions and language in humans as compared with other higher biological species. The main hypotheses of the origin and evolution of humans and their language are discussed, along with studies identifying genes responsible for higher functions. The cognitive capacities of animals and their communication signals are addressed, as are the basic principles of brain functions.

  2. Animal communication: hidden complexity.

    Science.gov (United States)

    Flack, Jessica C

    2013-11-04

    A hallmark of human communication is vocal turn taking. Until recently, turn taking was thought to be unique to humans but new data indicate that marmosets, a new world monkey, take turns when vocalizing too. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Vocal therapy of hyperkinetic dysphonia

    OpenAIRE

    Mumović Gordana; Veselinović Mila; Arbutina Tanja; Škrbić Renata

    2014-01-01

    Introduction. Hyperkinetic (hyperfunctional) dysphonia is a common pathology. The disorder is often found in vocal professionals faced with high vocal requirements. Objective. The objective of this study was to evaluate the effects of vocal therapy on voice condition characterized by hyperkinetic dysphonia with prenodular lesions and soft nodules. Methods. The study included 100 adult patients and 27 children aged 4-16 years with prenodular lesions and soft...

  4. Social ultrasonic vocalization in awake head-restrained mouse

    Directory of Open Access Journals (Sweden)

    Benjamin Weiner

    2016-12-01

    Full Text Available Numerous animal species emit vocalizations in response to various social stimuli. The neural basis of vocal communication has been investigated in monkeys, songbirds, rats, bats and invertebrates resulting in deep insights into motor control, neural coding and learning. Mice, which recently became very popular as a model system for mammalian neuroscience, also utilize ultrasonic vocalizations (USVs during mating behavior. However, our knowledge is lacking of both the behavior and its underlying neural mechanism. We developed a novel method for head-restrained male mice (HRMM to interact with non-restrained female mice (NRFM and show that mice can emit USVs in this context. We first recorded USVs in free arena with non-restrained male mice (NRMM and NRFM. Of the NRMM, which vocalized in the free arena, the majority could be habituated to also vocalize while head-restrained but only when a female mouse was present in proximity. The USVs emitted by HRMM are similar to the USVs of NRMM in the presence of a female mouse in their spectral structure, inter syllable interval distribution and USV sequence length, and therefore are interpreted as social USVs. By analyzing vocalizations of NRMM, we established criteria to predict which individuals are likely to vocalize while head fixed based on the USV rate and average syllable duration. To characterize the USVs emitted by HRMM, we analyzed the syllable composition of HRMM and NRMM and found that USVs emitted by HRMM have higher proportions of USVs with complex spectral representation, supporting previous studies showing that mice social USVs are context dependent. Our results suggest a way to study the neural mechanisms of production and control of social vocalization in mice using advanced methods requiring head fixation.

  5. Exploring the effects of communication intervention for developmental pragmatic language impairments: a signal-generation study.

    Science.gov (United States)

    Adams, Catherine; Lloyd, Julian; Aldred, Catherine; Baxendale, Janet

    2006-01-01

    The remediation of pragmatic problems forms a significant part of the caseload for professionals working with children with communication problems. There is little systematic evidence that demonstrates the benefits of speech and language therapy for children whose difficulties lie primarily within the pragmatic domain or which indicates whether changes in pragmatic behaviours, which are a result of a specific intervention, can be measured over time. To generate a signal of change in pragmatic and other language behaviours for children with pragmatic language impairments; to gauge the magnitude and nature of the signal and to make recommendations for future studies. A case series of six children with pragmatic language impairments without diagnosis of autism received 8 weeks of individual intensive speech and language therapy supported in a mainstream educational setting in the UK. Measures of pragmatic behaviours in conversation were made at seven data points before and after therapy using Bishop's ALICC procedure. Conversation coders were blind to the point of assessment. Inferential comprehension, narrative, sentence formulation and sentence recall skills were also tested before and after therapy. The opinions of teachers and parents were sought regarding any change in communication and social abilities of the children over time. All children showed change in communication behaviour on some conversational measures, even if the child functioned at the ceiling on standardized language testing. Some conversation measures had more utility as outcome measures than others. Most children showed substantial change on standardized language measures, but there are limitations on the use of these due to heterogeneity within the group. Overall, the intervention produced a signal for change in pragmatics and/or language behaviour in all children. Parent/teacher opinion reported demonstrable change in communication behaviour and engagement in the curriculum. There is a strong

  6. Measurement of vocal doses in virtual classrooms

    DEFF Research Database (Denmark)

    Bottalico, Pasquale; Pelegrin Garcia, David

    2010-01-01

    different acoustical conditions, that combined different kind of background noise and virtual classroom acoustics. Readings from the vocal fold vibrations were registered with an Ambulatory Phonation Monitor device. The speech signal from the talker in the center of the facility was picked up with a head......This work shows the results of a preliminary study about the determination of the optimal acoustical conditions for speakers in small classrooms. An experiment was carried out in a laboratory facility with 22 untrained talkers, who read a text passage from “Goldilocks” during two minutes under 13...... with an artificial head (corresponding to the mouth-ears path) placed at the talker position while simulating the classrooms. Time histories of the vocal fold vibration readings, with the trend of the fundamental frequency and an estimation of the sound pressure level, sampled every 50 ms, were obtained. From...

  7. Characterizing Vocal Repertoires--Hard vs. Soft Classification Approaches: e0125785

    National Research Council Canada - National Science Library

    Philip Wadewitz; Kurt Hammerschmidt; Demian Battaglia; Annette Witt; Fred Wolf; Julia Fischer

    2015-01-01

      To understand the proximate and ultimate causes that shape acoustic communication in animals, objective characterizations of the vocal repertoire of a given species are critical, as they provide...

  8. Non-Verbal Communication.

    Science.gov (United States)

    Hinde, R. A., Ed.

    This inter-disciplinary approach to the subject of non-verbal communication includes essays by linguists, zoologists, psychologists, anthropologists and a drama critic. It begins with a theoretical analysis of communicative processes written from the perspective of a communications engineer, compares vocal communication in animals and man, and…

  9. A New Signaling Architecture THREP with Autonomous Radio-Link Control for Wireless Communications Systems

    Science.gov (United States)

    Hirono, Masahiko; Nojima, Toshio

    This paper presents a new signaling architecture for radio-access control in wireless communications systems. Called THREP (for THREe-phase link set-up Process), it enables systems with low-cost configurations to provide tetherless access and wide-ranging mobility by using autonomous radio-link controls for fast cell searching and distributed call management. A signaling architecture generally consists of a radio-access part and a service-entity-access part. In THREP, the latter part is divided into two steps: preparing a communication channel, and sustaining it. Access control in THREP is thus composed of three separated parts, or protocol phases. The specifications of each phase are determined independently according to system requirements. In the proposed architecture, the first phase uses autonomous radio-link control because we want to construct low-power indoor wireless communications systems. Evaluation of channel usage efficiency and hand-over loss probability in the personal handy-phone system (PHS) shows that THREP makes the radio-access sub-system operations in a practical application model highly efficient, and the results of a field experiment show that THREP provides sufficient protection against severe fast CNR degradation in practical indoor propagation environments.

  10. Compensation of chromatic and polarization mode dispersion in fiber-optic communication lines in microwave signals transmittion.

    Science.gov (United States)

    Ermolaev, A. N.; Krishpents, G. P.; Davydov, V. V.; Vysoczkiy, M. G.

    2016-08-01

    Methods of dispersion compensation in fiber-optic communication lines. A new proposed method of electronic dispersion compensation in the transmission of microwave signals through fiber-optic lines. Represents is proposed the results of experimental studies of this method.

  11. Understanding Vocalization Might Help to Assess Stressful Conditions in Piglets

    Directory of Open Access Journals (Sweden)

    Diego Pereira Neves

    2013-09-01

    Full Text Available Assessing pigs’ welfare is one of the most challenging subjects in intensive pig farming. Animal vocalization analysis is a noninvasive procedure and may be used as a tool for assessing animal welfare status. The objective of this research was to identify stress conditions in piglets reared in farrowing pens through their vocalization. Vocal signals were collected from 40 animals under the following situations: normal (baseline, feeling cold, in pain, and feeling hunger. A unidirectional microphone positioned about 15 cm from the animals’ mouth was used for recording the acoustic signals. The microphone was connected to a digital recorder, where the signals were digitized at the 44,100 Hz frequency. The collected sounds were edited and analyzed. The J48 decision tree algorithm available at the Weka® data mining software was used for stress classification. It was possible to categorize diverse conditions from the piglets’ vocalization during the farrowing phase (pain, cold and hunger, with an accuracy rate of 81.12%. Results indicated that vocalization might be an effective welfare indicator, and it could be applied for assessing distress from pain, cold and hunger in farrowing piglets.

  12. An architecture for analysis and collection of RF signals used by hand-held devices in computer communications

    OpenAIRE

    Hwa, Chua Guan

    2001-01-01

    This thesis studies the wireless communications aspects of an Internetconnected hand-held device. It reviews the multipath effects of RF propagation and provides a detailed analysis of the Mobitex network protocols. Field experiments were conducted to measure the signal strength of indoor and outdoor reception. A framework for using real-time wireless communications analysis equipment for the collection of this RF signal is designed and discussed. Expected results from the collection of this ...

  13. Modeling the Pathophysiology of Phonotraumatic Vocal Hyperfunction With a Triangular Glottal Model of the Vocal Folds.

    Science.gov (United States)

    Galindo, Gabriel E; Peterson, Sean D; Erath, Byron D; Castro, Christian; Hillman, Robert E; Zañartu, Matías

    2017-09-18

    Our goal was to test prevailing assumptions about the underlying biomechanical and aeroacoustic mechanisms associated with phonotraumatic lesions of the vocal folds using a numerical lumped-element model of voice production. A numerical model with a triangular glottis, posterior glottal opening, and arytenoid posturing is proposed. Normal voice is altered by introducing various prephonatory configurations. Potential compensatory mechanisms (increased subglottal pressure, muscle activation, and supraglottal constriction) are adjusted to restore an acoustic target output through a control loop that mimics a simplified version of auditory feedback. The degree of incomplete glottal closure in both the membranous and posterior portions of the folds consistently leads to a reduction in sound pressure level, fundamental frequency, harmonic richness, and harmonics-to-noise ratio. The compensatory mechanisms lead to significantly increased vocal-fold collision forces, maximum flow-declination rate, and amplitude of unsteady flow, without significantly altering the acoustic output. Modeling provided potentially important insights into the pathophysiology of phonotraumatic vocal hyperfunction by demonstrating that compensatory mechanisms can counteract deterioration in the voice acoustic signal due to incomplete glottal closure, but this also leads to high vocal-fold collision forces (reflected in aerodynamic measures), which significantly increases the risk of developing phonotrauma.

  14. From uni- to multimodality: towards an integrative view on anuran communication.

    Science.gov (United States)

    Starnberger, Iris; Preininger, Doris; Hödl, Walter

    2014-09-01

    Undeniably, acoustic signals are the predominant mode of communication in frogs and toads. Acoustically active species are found throughout the vast diversity of anuran families. However, additional or alternative signal modalities have gained increasing attention. In several anurans, seismic, visual and chemical communications have convergently evolved due to ecological constraints such as noisy environments. The production of a visual cue, like the inevitably moving vocal sac of acoustically advertising males, is emphasized by conspicuously coloured throats. Limb movements accompanied by dynamic displays of bright colours are additional examples of striking visual signals independent of vocalizations. In some multimodal anuran communication systems, the acoustic component acts as an alert signal, which alters the receiver attention to the following visual display. Recent findings of colourful glands on vocal sacs, producing volatile species-specific scent bouquets suggest the possibility of integration of acoustic, visual and chemical cues in species recognition and mate choice. The combination of signal components facilitates a broadened display repertoire in challenging environmental conditions. Thus, the complexity of the communication systems of frogs and toads may have been underestimated.

  15. Vocal cord dysfunction in children.

    Science.gov (United States)

    Noyes, Blakeslee E; Kemp, James S

    2007-06-01

    Vocal cord dysfunction is characterised by paradoxical vocal cord adduction that occurs during inspiration, resulting in symptoms of dyspnoea, wheeze, chest or throat tightness and cough. Although the condition is well described in children and adults, confusion with asthma often triggers the use of an aggressive treatment regimen directed against asthma. The laryngoscopic demonstration of vocal cord adduction during inspiration has been considered the gold standard for the diagnosis of vocal cord dysfunction, but historical factors and pulmonary function findings may provide adequate clues to the correct diagnosis. Speech therapy, and in some cases psychological counselling, is often beneficial in this disorder. The natural course and prognosis of vocal cord dysfunction are still not well described in adults or children.

  16. Sophisticated Communication in the Brazilian Torrent Frog Hylodes japi.

    Science.gov (United States)

    de Sá, Fábio P; Zina, Juliana; Haddad, Célio F B

    2016-01-01

    Intraspecific communication in frogs plays an important role in the recognition of conspecifics in general and of potential rivals or mates in particular and therefore with relevant consequences for pre-zygotic reproductive isolation. We investigate intraspecific communication in Hylodes japi, an endemic Brazilian torrent frog with territorial males and an elaborate courtship behavior. We describe its repertoire of acoustic signals as well as one of the most complex repertoires of visual displays known in anurans, including five new visual displays. Previously unknown in frogs, we also describe a bimodal inter-sexual communication system where the female stimulates the male to emit a courtship call. As another novelty for frogs, we show that in addition to choosing which limb to signal with, males choose which of their two vocal sacs will be used for visual signaling. We explain how and why this is accomplished. Control of inflation also provides additional evidence that vocal sac movement and color must be important for visual communication, even while producing sound. Through the current knowledge on visual signaling in Neotropical torrent frogs (i.e. hylodids), we discuss and highlight the behavioral diversity in the family Hylodidae. Our findings indicate that communication in species of Hylodes is undoubtedly more sophisticated than we expected and that visual communication in anurans is more widespread than previously thought. This is especially true in tropical regions, most likely due to the higher number of species and phylogenetic groups and/or to ecological factors, such as higher microhabitat diversity.

  17. Sophisticated Communication in the Brazilian Torrent Frog Hylodes japi

    Science.gov (United States)

    de Sá, Fábio P.; Zina, Juliana; Haddad, Célio F. B.

    2016-01-01

    Intraspecific communication in frogs plays an important role in the recognition of conspecifics in general and of potential rivals or mates in particular and therefore with relevant consequences for pre-zygotic reproductive isolation. We investigate intraspecific communication in Hylodes japi, an endemic Brazilian torrent frog with territorial males and an elaborate courtship behavior. We describe its repertoire of acoustic signals as well as one of the most complex repertoires of visual displays known in anurans, including five new visual displays. Previously unknown in frogs, we also describe a bimodal inter-sexual communication system where the female stimulates the male to emit a courtship call. As another novelty for frogs, we show that in addition to choosing which limb to signal with, males choose which of their two vocal sacs will be used for visual signaling. We explain how and why this is accomplished. Control of inflation also provides additional evidence that vocal sac movement and color must be important for visual communication, even while producing sound. Through the current knowledge on visual signaling in Neotropical torrent frogs (i.e. hylodids), we discuss and highlight the behavioral diversity in the family Hylodidae. Our findings indicate that communication in species of Hylodes is undoubtedly more sophisticated than we expected and that visual communication in anurans is more widespread than previously thought. This is especially true in tropical regions, most likely due to the higher number of species and phylogenetic groups and/or to ecological factors, such as higher microhabitat diversity. PMID:26760304

  18. Low complexity method for spreading sequence estimation of DSSS signal in non-cooperative communication systems*

    Institute of Scientific and Technical Information of China (English)

    Chang Liang; Wang Fuping; Wang Zanji

    2009-01-01

    It is a necessary step to estimate the spreading sequence of direct sequence spread spectrum (DSSS) signal for blind despreading and demodulation in non-cooperative communications. Two innovative and effective detection statistics axe proposed to implement the synchronization and spreading sequence estimation procedure. The proposed algorithm also has a low computational complexity with only linear additions and modifications. Theoretical analysis and simulation results show that the algorithm performs quite well in low SNR environment, and is much better than all the existing typical algorithms with a comprehensive consideration both in performance and computational complexity.

  19. Calculation of mutual information for nonlinear communication channel at large signal-to-noise ratio

    Science.gov (United States)

    Terekhov, I. S.; Reznichenko, A. V.; Turitsyn, S. K.

    2016-10-01

    Using the path-integral technique we examine the mutual information for the communication channel modeled by the nonlinear Schrödinger equation with additive Gaussian noise. The nonlinear Schrödinger equation is one of the fundamental models in nonlinear physics, and it has a broad range of applications, including fiber optical communications—the backbone of the internet. At large signal-to-noise ratio we present the mutual information through the path-integral, which is convenient for the perturbative expansion in nonlinearity. In the limit of small noise and small nonlinearity we derive analytically the first nonzero nonlinear correction to the mutual information for the channel.

  20. Acoustic Tonal and Vector Properties of Red Hind Grouper Vocalizations

    Science.gov (United States)

    Matthews, Cameron Anthony

    Vertebrates are the most prodigious vocalizing animals in existence, and the most diverse methods of acoustic communication among vertebrates can be found in the ocean. Relatively many teleost fish are gifted with the ability to communicate acoustically, and the family of serranidae often performs this as a function of the swim bladder. Epinephelus Guttatus (E. guttatus), or more commonly the red hind grouper, is equipped with a drum shaped swim bladder acting as a monopole under typical ocean conditions. This configuration allows for what is understood to be omnidirectional projection of tones approximately centered between 40 and 440 Hz and spanning anywhere from 40 to 200 Hz of bandwidth and modulation effects based on observed data provided by researchers. Prior studies on many other fish show correlation in acoustic communication profile with length, size and sexual identity. In the red hind, sexual dimorphism leads to an inherent female identity in all juvenile fish which converts to male according to environmental factors, recommending at least consistent organs across both sexes be assumed even if not in use. Much research has been performed on male fish vocalization in terms of spectral content. Communication in fish is a complex multi-modal process, with acoustic communication being important for many of the species, particularly those in the littoral regions of the worlds' oceans. If identifying characteristics of the red hind vocalization can be isolated based on detection, classification, tracking and localizing methodologies, then these identifying characteristics may indeed lead to passive feature identification that allows for estimation of individual fish mass. Hypotheses based on vector, cyclostationary and classical tonal mechanics are presented for consideration. A battery of test data collection events, applying pre-recorded fish vocalizations to a geolocated undersea sound source were conducted. The results are supplied with the intent of

  1. Ontogenesis of agonistic vocalizations in the cichlid fish Metriaclima zebra.

    Science.gov (United States)

    Bertucci, Frédéric; Scaion, Delphine; Beauchaud, Marilyn; Attia, Joël; Mathevon, Nicolas

    2012-08-01

    While acoustic communication has been described in adults of various fish species, our knowledge about the ontogeny of fish sound production is limited. In adults, sound signals are known to be involved during aggressive interactions. However, aggressive behaviour may appear early in the life of fishes due to the possible competition for food and space. If acoustic signals are used to send information to competitors, sounds are likely to play a role during interactions between juvenile fish as well. The apparition and evolution of sound production were monitored in a group of juveniles of the cichlid fish Metriaclima zebra from hatching to 4 months of age. In addition, the link between vocalizations and agonistic behaviour was studied during dyadic interactions at three different ages. Sounds production appeared to be present early in the development of this fish and increased along with the number of aggressive behaviours. Recorded sounds consisted, in juveniles, in isolated pulses showing a decrease in frequency and duration as the fish grew. In adults, sounds became bursts of pulses but the transition from isolated to repetitive pulses was not observed. These results are compared to the existing literature on sound production ontogeny in fishes.

  2. Small-Signal Analysis of the Microgrid Secondary Control Considering a Communication Time Delay

    DEFF Research Database (Denmark)

    Coelho, Ernane Antônio Alves; Wu, Dan; Guerrero, Josep M.

    2016-01-01

    This paper presents a small-signal analysis of an islanded microgrid composed of two or more voltage-source inverters connected in parallel. The primary control of each inverter is integrated through an internal current and voltage loops using proportional resonant compensators, a virtual impedance......, and an external power controller based on frequency and voltage droops. The frequency restoration function is implemented at the secondary control level, which executes a consensus algorithm that consists of a load-frequency control and a single time delay communication network. The consensus network consists...... of a time-invariant directed graph and the output power of each inverter is the information shared among the units, which is affected by the time delay. The proposed small-signal model is validated through simulation results and experimental results. A root locus analysis is presented that shows...

  3. Silicon Nanowires for All-Optical Signal Processing in Optical Communication

    DEFF Research Database (Denmark)

    Pu, Minhao; Hu, Hao; Ji, Hua;

    2012-01-01

    to the large mode mismatch and index mismatch. Both end-coupling and grating-coupling solution utilizing nano-structures were demonstrated with optimized coupling efficiencies, which make the silicon on-chip nanowire devices more practical for real optical communication systems.......Silicon (Si), the second most abundant element on earth, has dominated in microelectronics for many decades. It can also be used for photonic devices due to its transparency in the range of optical telecom wavelengths which will enable a platform for a monolithic integration of optics...... process. In the last four years, we investigated and demonstrated different ultra-fast all-optical nonlinear signal processing applications in silicon nanowires for optical time domain multiplexing (OTDM) systems, including wavelength conversion, signal regeneration, ultra-fast waveform sampling...

  4. [Monitor of ECG signal and heart rate using a mobile phone with Bluetooth communication protocol].

    Science.gov (United States)

    Becerra-Luna, Brayans; Dávila-García, Rodrigo; Salgado-Rodríguez, Paola; Martínez-Memije, Raúl; Infante-Vázquez, Oscar

    2012-01-01

    To develop a portable signal monitoring equipment for electrocardiography (ECG) and heart rate (HR), communicated with a mobile phone using the Bluetooth (BT) communication protocol for display of the signal on screen. A monitoring system was designed in which the electronic section performs the ECG signal acquisition, as well as amplification, filtering, analog to digital conversion and transmission of the ECG and HR using BT. Two programs were developed for the system. The first one calculates HR through QRS identification and sends the ECG signals and HR to the mobile, and the second program is an application to acquire and display them on the mobile screen. We developed a portable electronic system powered by a 9 volt battery, with amplification and bandwidth meeting the international standards for ECG monitoring. The QRS complex identification was performed using the second derivative algorithm, while the programs allow sending and receiving information from the ECG and HR via BT, and viewing it on the mobile screen. The monitoring is feasible within distances of 15 m and it has been tested in various mobiles telephones of brands Nokia®, Sony Ericsson® and Samsung®. This system shows an alternative for mobile monitoring using BT and Java 2 Micro Edition (J2ME) programming. It allows the register of the ECG trace and HR, and it can be implemented in different phones. Copyright © 2011 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.

  5. Visible light communications using predistortion signal to enhance the response of passive optical receiver

    Science.gov (United States)

    Liu, Yang; Chen, Hung-Yu; Liang, Kevin; Wei, Liang-Yu; Chow, Chi-Wai; Yeh, Chien-Hung

    2016-01-01

    Traditional visible light communication (VLC) uses positive-intrinsic-negative photodiode (PD) or avalanche PD as the optical receivers (Rx). We demonstrate using a solar cell as the VLC Rx. The solar cell is flexible and low cost and converts the optical signal into an electrical signal directly without the need of external power supply. In addition to acting as the VLC passive Rx, the converted electrical signal from the solar cell can charge up the battery of the Rx nodes. Hence, the proposed scheme can be a promising candidate for the future Internet of Things network. However, a solar cell acting as a VLC Rx is very challenging, since the response of the solar cell is limited. Here, we propose and demonstrate using predistortion to significantly enhance the solar cell Rx response for the first time up to the authors' knowledge. Experimental results show that the response of the solar cell Rx is significantly enhanced; and the original 2-kHz detection bandwidth of the solar cell can be enhanced by 250 times for receiving 500-kbit/s VLC signal at a transmission distance of 1 m. The operation principle, the generated voltage by the solar cell, and the maximum data rates achieved at different transmission distances are also studied.

  6. Adaptive reception of aggregate frequency signals in an underwater acoustic communications channel under different types of interference

    Science.gov (United States)

    Bobrovskii, I. V.; Rybina, M. S.; Melent'ev, V. D.; Yagotinets, V. P.

    2017-05-01

    The paper presents the results of experimental research on a multichannel underwater acoustic communications system that increases the digital information rate by aggregate frequency signals under deepsea conditions with multipath signal propagation. Quantitative estimates of information reception quality under various types of interference are given.

  7. Finite element modelling of vocal tract changes after voice therapy

    Directory of Open Access Journals (Sweden)

    Vampola T.

    2011-06-01

    Full Text Available Two 3D finite element (FE models were constructed, based on CT measurements of a subject phonating on [a:] before and after phonation into a tube. Acoustic analysis was performed by exciting the models with acoustic flow velocity at the vocal folds. The generated acoustic pressure of the response was computed in front of the mouth and inside the vocal tract for both FE models. Average amplitudes of the pressure oscillations inside the vocal tract and in front of the mouth were compared to display the cost-efficiency of sound energy transfer at different formant frequencies. The formants F1–F3 correspond to classical vibration modes also solvable by 1D vocal tract model. However, for higher formants, there occur more complicated transversal modes which require 3D modelling. A special attention is given to the higher frequency range (above 3.5 Hz where transversal modes exist between piriform sinuses and valleculae. Comparison of the pressure oscillation inside and outside the vocal tract showed that formants differ in their efficiency, F4 (at about 3.5 kHz, i.e. at the speaker’s or singer’s formant region being the most effective. The higher formants created a clear formant cluster around 4 kHz after the vocal exercise with the tube. Since the human ear is most sensitive to frequencies between 2 and 4 kHz concentration of sound energy in this frequency region (F4–F5 is effective for communication. The results suggest that exercising using phonation into tubes help in improving the vocal economy.

  8. Quorum sensing communication between bacteria and human cells: signals, targets and functions

    Directory of Open Access Journals (Sweden)

    Angelika eHolm

    2014-06-01

    Full Text Available Both direct and long-range interactions between pathogenic Pseudomonas aeruginosa bacteria and their eukaryotic hosts are important in the outcome of infections. For cell-to-cell communication, these bacteria employ the quorum sensing (QS system to pass on information of the density of the bacterial population and collectively switch on virulence factor production, biofilm formation and resistance development. Thus, QS allows bacteria to behave as a community to perform tasks which would be impossible for individual cells, e.g. to overcome defense and immune systems and establish infections in higher organisms. This review highlights these aspects of QS and our own recent research on how P.aeruginosa communicates with human cells using the small QS signal molecules N-acyl homoserine lactones (AHL. We focus on how this conversation changes the behavior and function of neutrophils, macrophages and epithelial cells and on how the signaling machinery in human cells responsible for the recognition of AHL. Understanding the bacteria-host relationships at both cellular and molecular levels is essential for the identification of new targets and for the development of novel strategies to fight bacterial infections in the future.

  9. Communication

    NARCIS (Netherlands)

    Sigafoos, J.; Lancioni, G.E.; O'Reilly, M.F.; Lang, R.; Singh, N.N.; Didden, H.C.M.; Green, V.A.; Marschik, P.B.

    2016-01-01

    Communication disorders are common among people with intellectual disabilities. Consequently, enhancing the communication skills of such individuals is a major intervention priority. This chapter reviews the nature and prevalence of the speech, language, and communication problems associated with

  10. Enhancing Performance of Optical Communication Systems with Advanced Optical Signal Processing

    Directory of Open Access Journals (Sweden)

    Ivan Glesk

    2010-11-01

    Full Text Available Growing needs to transport large amount of data, penetration of multimedia into our daily lives, and quickly expanding e-Commerce sector triggered an unparallel demand for the new generation of fast, secure, and energy savvy communication networks.Today we already benefit from many advances which revolutionized data and voice communication. Commercially deployed Dense Wavelength Division Multiple Access (DWDMA networks today are capable of transporting tens of Gigabits of data per second over a single WDM channel thus offering tremendous aggregate data throughputs over a single optical fibre. As a consequence, new bottlenecks have emerged at the fibre endpoints where data detection, routing, and switching must take place. Today's routers use electronics to process all incoming optical traffic. However the available bandwidth offered by current electronics can no longer keep up with these rapidly growing demands. To address these challenges and with goal in mind to eliminate this bottleneck, the research community has been looking long and hard for appropriate alternative solutions. One of taken approaches can be described as optical signal processing. As we will demonstrate it can be very powerful tool to improve performance of advanced communication networks especially when coupled with technologies and approaches which will enable device integration and packaging.

  11. Neurons controlling voluntary vocalization in the macaque ventral premotor cortex.

    Directory of Open Access Journals (Sweden)

    Gino Coudé

    Full Text Available The voluntary control of phonation is a crucial achievement in the evolution of speech. In humans, ventral premotor cortex (PMv and Broca's area are known to be involved in voluntary phonation. In contrast, no neurophysiological data are available about the role of the oro-facial sector of nonhuman primates PMv in this function. In order to address this issue, we recorded PMv neurons from two monkeys trained to emit coo-calls. Results showed that a population of motor neurons specifically fire during vocalization. About two thirds of them discharged before sound onset, while the remaining were time-locked with it. The response of vocalization-selective neurons was present only during conditioned (voluntary but not spontaneous (emotional sound emission. These data suggest that the control of vocal production exerted by PMv neurons constitutes a newly emerging property in the monkey lineage, shedding light on the evolution of phonation-based communication from a nonhuman primate species.

  12. Decreased approach behavior and nucleus accumbens immediate early gene expression in response to Parkinsonian ultrasonic vocalizations in rats

    OpenAIRE

    2015-01-01

    Many individuals with Parkinson disease (PD) have difficulty producing normal speech and voice, resulting in problems with interpersonal communication and reduced quality of life. Translational animal models of communicative dysfunction have been developed to assess disease pathology. However, it is unknown whether acoustic feature changes associated with vocal production deficits in these animal models lead to compromised communication. In rodents, male ultrasonic vocalizations (USVs) have a...

  13. Vocal therapy of hyperkinetic dysphonia

    Directory of Open Access Journals (Sweden)

    Mumović Gordana

    2014-01-01

    Full Text Available Introduction. Hyperkinetic (hyperfunctional dysphonia is a common pathology. The disorder is often found in vocal professionals faced with high vocal requirements. Objective. The objective of this study was to evaluate the effects of vocal therapy on voice condition characterized by hyperkinetic dysphonia with prenodular lesions and soft nodules. Methods. The study included 100 adult patients and 27 children aged 4-16 years with prenodular lesions and soft nodules. A subjective acoustic analysis using the GIRBAS scale was performed prior to and after vocal therapy. Twenty adult patients and 10 children underwent objective acoustic analysis including several acoustic parameters. Pathological vocal qualities (hoarse, harsh and breathy voice were also obtained by computer analysis. Results. The subjective acoustic analysis revealed a significant (p<0.01 reduction in all dysphonia parameters after vocal treatment in adults and children. After treatment, all levels of dysphonia were lowered in 85% (85/100 of adult patients and 29% (29/100 had a normal voice. Before vocal therapy 9 children had severe, 13 had moderate and 8 slight dysphonia. After vocal therapy only 1 child had severe dysphonia, 7 had moderate, 10 had slight levels of dysphonia and 9 were without voice disorder. The objective acoustic analysis in adults revealed a significant improvement (p≤0.025 in all dysphonia parameters except SD F0 and jitter %. In children, the acoustic parameters SD F0, jitter % and NNE (normal noise energy were significantly improved (p=0.003-0.03. Pathological voice qualities were also improved in adults and children (p<0.05. Conclusion. Vocal therapy effectively improves the voice in hyperkinetic dysphonia with prenodular lesions and soft nodules in both adults and children, affecting diverse acoustic parameters.

  14. A small towed beamforming array to identify vocalizing resident killer whales ( Orcinus orca) concurrent with focal behavioral observations

    Science.gov (United States)

    Miller, Patrick J.; Tyack, Peter L.

    Investigations of communication systems benefit from concurrent observation of vocal and visible behaviors of individual animals. A device has been developed to identify individual vocalizing resident killer whales ( Orcinus orca) during focal behavioral observations. The device consists of a 2-m, 15-element hydrophone array, which is easily towed behind a small vessel, on-board multi-channel recorders, and real-time signal processing equipment. Acoustic data from the hydrophones are digitized and processed using broadband frequency-domain beamforming to yield frequency-azimuth (FRAZ) and "directo-gram" displays of arriving sounds. Based upon statistical analysis of independent portions of typical killer whale calls, the precision of the angle-of-arrival estimate ranges from ±0° to ±2.5° with a mean precision of ±1.5°. Echolocation clicks also are resolved precisely with a typical -6 dB mainlobe width of ±2.0°. Careful positioning of the array relative to the animals minimizes the effects of depth ambiguities and allows identification of individual sources in many circumstances. Several strategies for identifying vocalizing individuals are discussed and an example of a successful identification is described. Use of the array with resident killer whales did not interfere with vessel maneuverability, animal tracking, or behavioral sampling of focal individuals. This localization technique has promise for advancing the abilities of researchers to conduct unbiased behavioral and acoustic sampling of individual free-ranging cetaceans.

  15. Superfast vocal muscles control song production in songbirds.

    Directory of Open Access Journals (Sweden)

    Coen P H Elemans

    Full Text Available Birdsong is a widely used model for vocal learning and human speech, which exhibits high temporal and acoustic diversity. Rapid acoustic modulations are thought to arise from the vocal organ, the syrinx, by passive interactions between the two independent sound generators or intrinsic nonlinear dynamics of sound generating structures. Additionally, direct neuromuscular control could produce such rapid and precisely timed acoustic features if syringeal muscles exhibit rare superfast muscle contractile kinetics. However, no direct evidence exists that avian vocal muscles can produce modulations at such high rates. Here, we show that 1 syringeal muscles are active in phase with sound modulations during song over 200 Hz, 2 direct stimulation of the muscles in situ produces sound modulations at the frequency observed during singing, and that 3 syringeal muscles produce mechanical work at the required frequencies and up to 250 Hz in vitro. The twitch kinematics of these so-called superfast muscles are the fastest measured in any vertebrate muscle. Superfast vocal muscles enable birds to directly control the generation of many observed rapid acoustic changes and to actuate the millisecond precision of neural activity into precise temporal vocal control. Furthermore, birds now join the list of vertebrate classes in which superfast muscle kinetics evolved independently for acoustic communication.

  16. Voice Modulation: A Window into the Origins of Human Vocal Control?

    Science.gov (United States)

    Pisanski, Katarzyna; Cartei, Valentina; McGettigan, Carolyn; Raine, Jordan; Reby, David

    2016-04-01

    An unresolved issue in comparative approaches to speech evolution is the apparent absence of an intermediate vocal communication system between human speech and the less flexible vocal repertoires of other primates. We argue that humans' ability to modulate nonverbal vocal features evolutionarily linked to expression of body size and sex (fundamental and formant frequencies) provides a largely overlooked window into the nature of this intermediate system. Recent behavioral and neural evidence indicates that humans' vocal control abilities, commonly assumed to subserve speech, extend to these nonverbal dimensions. This capacity appears in continuity with context-dependent frequency modulations recently identified in other mammals, including primates, and may represent a living relic of early vocal control abilities that led to articulated human speech.

  17. Social learning of vocal structure in a nonhuman primate?

    Directory of Open Access Journals (Sweden)

    Lemasson Alban

    2011-12-01

    Full Text Available Abstract Background Non-human primate communication is thought to be fundamentally different from human speech, mainly due to vast differences in vocal control. The lack of these abilities in non-human primates is especially striking if compared to some marine mammals and bird species, which has generated somewhat of an evolutionary conundrum. What are the biological roots and underlying evolutionary pressures of the human ability to voluntarily control sound production and learn the vocal utterances of others? One hypothesis is that this capacity has evolved gradually in humans from an ancestral stage that resembled the vocal behavior of modern primates. Support for this has come from studies that have documented limited vocal flexibility and convergence in different primate species, typically in calls used during social interactions. The mechanisms underlying these patterns, however, are currently unknown. Specifically, it has been difficult to rule out explanations based on genetic relatedness, suggesting that such vocal flexibility may not be the result of social learning. Results To address this point, we compared the degree of acoustic similarity of contact calls in free-ranging Campbell's monkeys as a function of their social bonds and genetic relatedness. We calculated three different indices to compare the similarities between the calls' frequency contours, the duration of grooming interactions and the microsatellite-based genetic relatedness between partners. We found a significantly positive relation between bond strength and acoustic similarity that was independent of genetic relatedness. Conclusion Genetic factors determine the general species-specific call repertoire of a primate species, while social factors can influence the fine structure of some the call types. The finding is in line with the more general hypothesis that human speech has evolved gradually from earlier primate-like vocal communication.

  18. Physiologically driven avian vocal synthesizer

    Science.gov (United States)

    Sitt, Jacobo D.; Arneodo, Ezequiel M.; Goller, Franz; Mindlin, Gabriel B.

    2010-03-01

    In this work, we build an electronic syrinx, i.e., a programmable electronic device capable of integrating biomechanical model equations for the avian vocal organ in order to synthesize song. This vocal prosthesis is controlled by the bird’s neural instructions to respiratory and the syringeal motor systems, thus opening great potential for studying motor control and its modification by sensory feedback mechanisms. Furthermore, a well-functioning subject-controlled vocal prosthesis can lay the foundation for similar devices in humans and thus provide directly health-related data and procedures.

  19. Biomechanical control of vocal plasticity in an echolocating bat.

    Science.gov (United States)

    Luo, Jinhong; Wiegrebe, Lutz

    2016-03-01

    Many animal species adjust the spectral composition of their acoustic signals to variable environments. However, the physiological foundation of such spectral plasticity is often unclear. The source-filter theory of sound production, initially established for human speech, applies to vocalizations in birds and mammals. According to this theory, adjusting the spectral structure of vocalizations could be achieved by modifying either the laryngeal/syringeal source signal or the vocal tract, which filters the source signal. Here, we show that in pale spear-nosed bats, spectral plasticity induced by moderate level background noise is dominated by the vocal tract rather than the laryngeal source signal. Specifically, we found that with increasing background noise levels, bats consistently decreased the spectral centroid of their echolocation calls up to 3.2 kHz, together with other spectral parameters. In contrast, noise-induced changes in fundamental frequency were small (maximally 0.1 kHz) and were inconsistent across individuals. Changes in spectral centroid did not correlate with changes in fundamental frequency, whereas they correlated negatively with changes in call amplitude. Furthermore, while bats consistently increased call amplitude with increasing noise levels (the Lombard effect), increases in call amplitude typically did not lead to increases in fundamental frequency. In summary, our results suggest that at least to a certain degree echolocating bats are capable of adjusting call amplitude, fundamental frequency and spectral parameters independently. © 2016. Published by The Company of Biologists Ltd.

  20. Modal locking between vocal fold and vocal tract oscillations

    CERN Document Server

    Aalto, Atte; Malinen, Jarmo; Vainio, Martti

    2012-01-01

    The human vocal folds are known to interact with the vocal tract acoustics during voiced speech production; namely a nonlinear source-filter coupling has been observed both by using models and in \\emph{in vivo} phonation. These phenomena are approached from two directions in this article. We first present a computational dynamical model of the speech apparatus that contains an explicit filter-source feedback mechanism from the vocal tract acoustics back to the vocal folds oscillations. The model was used to simulate vocal pitch glideswhere the trajectory was forced to cross the lowest vocal tract resonance, i.e., the lowest formant $F_1$. Similar patterns produced by human participants were then studied. Both the simulations and the experimental results reveal an effect when the glides cross the first formant (as may happen in \\textipa{[i]}). Conversely, this effect is not observed if there is no formant within the glide range (as is the case in \\textipa{[\\textscripta]}). The experiments show smaller effect c...

  1. An Integrated Signaling-Encryption Mechanism to Reduce Error Propagation in Wireless Communications: Performance Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Olama, Mohammed M [ORNL; Matalgah, Mustafa M [ORNL; Bobrek, Miljko [ORNL

    2015-01-01

    Traditional encryption techniques require packet overhead, produce processing time delay, and suffer from severe quality of service deterioration due to fades and interference in wireless channels. These issues reduce the effective transmission data rate (throughput) considerably in wireless communications, where data rate with limited bandwidth is the main constraint. In this paper, performance evaluation analyses are conducted for an integrated signaling-encryption mechanism that is secure and enables improved throughput and probability of bit-error in wireless channels. This mechanism eliminates the drawbacks stated herein by encrypting only a small portion of an entire transmitted frame, while the rest is not subject to traditional encryption but goes through a signaling process (designed transformation) with the plaintext of the portion selected for encryption. We also propose to incorporate error correction coding solely on the small encrypted portion of the data to drastically improve the overall bit-error rate performance while not noticeably increasing the required bit-rate. We focus on validating the signaling-encryption mechanism utilizing Hamming and convolutional error correction coding by conducting an end-to-end system-level simulation-based study. The average probability of bit-error and throughput of the encryption mechanism are evaluated over standard Gaussian and Rayleigh fading-type channels and compared to the ones of the conventional advanced encryption standard (AES).

  2. In Search of Autocorrelation Based Vocal Cord Cues for Speaker Identification

    CERN Document Server

    Sahidullah, Md

    2011-01-01

    In this paper we investigate a technique to find out vocal source based features from the LP residual of speech signal for automatic speaker identification. Autocorrelation with some specific lag is computed for the residual signal to derive these features. Compared to traditional features like MFCC, PLPCC which represent vocal tract information, these features represent complementary vocal cord information. Our experiment in fusing these two sources of information in representing speaker characteristics yield better speaker identification accuracy. We have used Gaussian mixture model (GMM) based speaker modeling and results are shown on two public databases to validate our proposition.

  3. Adaptive vocal behavior drives perception by echolocation in bats

    DEFF Research Database (Denmark)

    Moss, Cynthia F; Chiu, Chen; Surlykke, Annemarie

    2011-01-01

    Echolocation operates through adaptive sensorimotor systems that collectively enable the bat to localize and track sonar objects as it flies. The features of sonar signals used by a bat to probe its surroundings determine the information available to its acoustic imaging system. In turn, the bat......'s perception of a complex scene guides its active adjustments in the features of subsequent sonar vocalizations. Here, we propose that the bat's active vocal-motor behaviors play directly into its representation of a dynamic auditory scene....

  4. Vocal Improvisation for Elementary Students.

    Science.gov (United States)

    Thompson, Keith P.

    1980-01-01

    The author describes the three-phase process of musical creativity (exploratory, invention, organizational), identifying activities in each of the creative phases. Included are vocal impression, picture sounds, chord tones, and name improvisation. Selected readings and recordings are included. (KC)

  5. Vocal therapy of hyperkinetic dysphonia.

    Science.gov (United States)

    Mumović, Gordana; Veselinović, Mila; Arbutina, Tanja; Škrbić, Renata

    2014-01-01

    Hyperkinetic (hyperfunctional) dysphonia is a common pathology. The disorder is often found in vocal professionals faced with high vocal requirements. The objective of this study was to evaluate the effects of vocal therapy on voice condition characterized by hyperkinetic dysphonia with prenodular lesions and soft nodules. The study included 100 adult patients and 27 children aged 4-16 years with prenodular lesions and soft nodules. A subjective acoustic analysis using the GIRBAS scale was performed prior to and after vocal therapy. Twenty adult patients and 10 children underwent objective acoustic analysis including several acoustic parameters. Pathological vocal qualities (hoarse, harsh and breathy voice) were also obtained by computer analysis. The subjective acoustic analysis revealed a significant (pdysphonia parameters after vocal treatment in adults and children. After treatment, all levels of dysphonia were lowered in 85% (85/100) of adult patients and 29% (29/100) had a normal voice. Before vocal therapy 9 children had severe, 13 had moderate and 8 slight dysphonia. After vocal therapy only 1 child had severe dysphonia, 7 had moderate, 10 had slight levels of dysphonia and 9 were without voice disorder. The objective acoustic analysis in adults revealed a significant improvement (p≤0.025) in all dysphonia parameters except SD FO and jitter %. In children, the acoustic parameters SD FO, jitter % and NNE (normal noise energy) were significantly improved (p=0.003-0.03). Pathological voice qualities were also improved in adults and children (pdysphonia with prenodular lesions and soft nodules in both adults and children, affectinq diverse acoustic parameters.

  6. Hydrodynamics of Planktonic Microcrustacean Locomotion: Turning Wake Vortices into Communication Signals

    Science.gov (United States)

    Yen, Jeannette; Gilmanov, Anvar; Sotiropoulos, Fotis

    2003-11-01

    It has long been hypothesized that aquatic microcrustaceans, such as planktonic copepods, are able to distinguish an attractive mate from a lunging predator by sensing their respective hydrodynamic signatures in the form of coherent vortical structures. We develop a hybrid Cartesian/Immersed-Boundary numerical method for simulating the flow around a swimming copepod. A realistic copepod-like body is constructed, which includes most important parts of the animals anatomy: the antenulles, legs, and tail. The kinematics of the individual body parts are prescribed using laboratory observations and measurements. We will report numerical simulations for a copepod advancing at steady velocity over a range of Reynolds numbers, 10communication signals.

  7. Brain and face: communicating signals of health in the left and right sides of the face.

    Science.gov (United States)

    Reis, V A; Zaidel, D W

    2001-01-01

    In human communication and mate selection the appearance of health sends signals regarding biological fitness. We compared the appearance of health in the sides of the face to previous results on left-right facial asymmetry in the appearance of beauty (1). The stimuli were created by aligning the left and right sides of the face each with its own mirror image. Here, participants viewed 38 pairs of left-left and right-right faces and judged which member of the pair looked healthier. No significant interaction emerged between decision (health vs attractiveness) and face side. Rather, in women's faces right-right was significantly more healthy and attractive than left-left, while in men's faces there was no significant left-right difference. In biology and evolution, health and beauty are closely linked and the findings here confirm this relationship in human faces.

  8. Perceptual fluency and judgments of vocal aesthetics and stereotypicality.

    Science.gov (United States)

    Babel, Molly; McGuire, Grant

    2015-05-01

    Research has shown that processing dynamics on the perceiver's end determine aesthetic pleasure. Specifically, typical objects, which are processed more fluently, are perceived as more attractive. We extend this notion of perceptual fluency to judgments of vocal aesthetics. Vocal attractiveness has traditionally been examined with respect to sexual dimorphism and the apparent size of a talker, as reconstructed from the acoustic signal, despite evidence that gender-specific speech patterns are learned social behaviors. In this study, we report on a series of three experiments using 60 voices (30 females) to compare the relationship between judgments of vocal attractiveness, stereotypicality, and gender categorization fluency. Our results indicate that attractiveness and stereotypicality are highly correlated for female and male voices. Stereotypicality and categorization fluency were also correlated for male voices, but not female voices. Crucially, stereotypicality and categorization fluency interacted to predict attractiveness, suggesting the role of perceptual fluency is present, but nuanced, in judgments of human voices.

  9. Non-Linguistic Vocal Event Detection Using Online Random

    DEFF Research Database (Denmark)

    Abou-Zleikha, Mohamed; Tan, Zheng-Hua; Christensen, Mads Græsbøll

    2014-01-01

    Accurate detection of non-linguistic vocal events in social signals can have a great impact on the applicability of speech enabled interactive systems. In this paper, we investigate the use of random forest for vocal event detection. Random forest technique has been successfully employed in many...... areas such as object detection, face recognition, and audio event detection. This paper proposes to use online random forest technique for detecting laughter and filler and for analyzing the importance of various features for non-linguistic vocal event classification through permutation. The results...... show that according to the Area Under Curve measure the online random forest achieved 88.1% compared to 82.9% obtained by the baseline support vector machines for laughter classification and 86.8% to 83.6% for filler classification....

  10. Signal Processing for Wireless Communication MIMO System with Nano- Scaled CSDG MOSFET based DP4T RF Switch.

    Science.gov (United States)

    Srivastava, Viranjay M

    2015-01-01

    In the present technological expansion, the radio frequency integrated circuits in the wireless communication technologies became useful because of the replacement of increasing number of functions, traditional hardware components by modern digital signal processing. The carrier frequencies used for communication systems, now a day, shifted toward the microwave regime. The signal processing for the multiple inputs multiple output wireless communication system using the Metal- Oxide-Semiconductor Field-Effect-Transistor (MOSFET) has been done a lot. In this research the signal processing with help of nano-scaled Cylindrical Surrounding Double Gate (CSDG) MOSFET by means of Double- Pole Four-Throw Radio-Frequency (DP4T RF) switch, in terms of Insertion loss, Isolation, Reverse isolation and Inter modulation have been analyzed. In addition to this a channel model has been presented. Here, we also discussed some patents relevant to the topic.

  11. Cytokinins and auxin communicate nitrogen availability as long-distance signal molecules in pineapple (Ananas comosus).

    Science.gov (United States)

    Tamaki, Vívian; Mercier, Helenice

    2007-11-01

    This work aimed at identifying a possible role of phytohormones in long-distance (root-shoot) signaling under nitrogen deficiency. Three-months old pineapple plants were transferred from Murashige and Skoog (MS) medium to nitrogen-free MS (-N). During the first 24h on -N, 20 plants were harvested every 4h. After 30 days in -N, the remaining plants were transferred back to regular MS (+N) and 20 plants harvested every 4h for the first 24h. Following the harvests, endogenous levels of nitrate (NO(3)(-)), indole-3-acetic acid (IAA), isopentenyladenine (iP), isopentenyladenine riboside (iPR), zeatin (Z) and zeatin riboside (ZR) were analyzed in roots and leaves. In N-starved plants, the NO(3)(-) level dropped by 20% in roots between the first (4h) and the second harvest (8h). In leaves a reduction of 20% was found 4h later. Accumulation of IAA peaked in leaves at 16h. In roots, the accumulation of IAA only started at 16h while the leaf content was already in decline, which suggests that the hormone might have traveled from the leaves to the roots, communicating N-shortage. The contents of the four cytokinins were generally low in both, shoot and roots, and remained almost unchanged during the 24h of analysis. After N re-supply, roots showed a NO(3)(-) peak at 8h whereas the foliar concentration increased 4h later. Hormone levels in roots climaxed at 8h, this coinciding with the highest NO(3)(-) concentration. In leaf tissue, a dramatic accumulation was only observed for Z and ZR, and the peak was seen 4h later than in roots, suggesting that Z-type cytokinins might have traveled from the roots to the leaves. These findings provide evidence that there is a signaling pathway for N availability in pineapple plants, communicated upwards through cytokinins (N-supplemented plants) and downwards through auxin (N-starved plants).

  12. Something in the way she sings: enhanced memory for vocal melodies.

    Science.gov (United States)

    Weiss, Michael W; Trehub, Sandra E; Schellenberg, E Glenn

    2012-10-01

    Across species, there is considerable evidence of preferential processing for biologically significant signals such as conspecific vocalizations and the calls of individual conspecifics. Surprisingly, music cognition in human listeners is typically studied with stimuli that are relatively low in biological significance, such as instrumental sounds. The present study explored the possibility that melodies might be remembered better when presented vocally rather than instrumentally. Adults listened to unfamiliar folk melodies, with some presented in familiar timbres (voice and piano) and others in less familiar timbres (banjo and marimba). They were subsequently tested on recognition of previously heard melodies intermixed with novel melodies. Melodies presented vocally were remembered better than those presented instrumentally even though they were liked less. Factors underlying the advantage for vocal melodies remain to be determined. In line with its biological significance, vocal music may evoke increased vigilance or arousal, which in turn may result in greater depth of processing and enhanced memory for musical details.

  13. Developmental change and cross-domain links in vocal and musical emotion recognition performance in childhood.

    Science.gov (United States)

    Allgood, Rebecca; Heaton, Pamela

    2015-09-01

    Although the configurations of psychoacoustic cues signalling emotions in human vocalizations and instrumental music are very similar, cross-domain links in recognition performance have yet to be studied developmentally. Two hundred and twenty 5- to 10-year-old children were asked to identify musical excerpts and vocalizations as happy, sad, or fearful. The results revealed age-related increases in overall recognition performance with significant correlations across vocal and musical conditions at all developmental stages. Recognition scores were greater for musical than vocal stimuli and were superior in females compared with males. These results confirm that recognition of emotions in vocal and musical stimuli is linked by 5 years and that sensitivity to emotions in auditory stimuli is influenced by age and gender.

  14. Communication of Ca(2+) signals via tunneling membrane nanotubes is mediated by transmission of inositol trisphosphate through gap junctions.

    Science.gov (United States)

    Lock, Jeffrey T; Parker, Ian; Smith, Ian F

    2016-10-01

    Tunneling membrane nanotubes (TNTs) are thin membrane projections linking cell bodies separated by many micrometers, which are proposed to mediate signaling and even transfer of cytosolic contents between distant cells. Several reports describe propagation of Ca(2+) signals between distant cells via TNTs, but the underlying mechanisms remain poorly understood. Utilizing a HeLa M-Sec cell line engineered to upregulate TNTs we replicated previous findings that mechanical stimulation elicits robust cytosolic Ca(2+) elevations that propagate to surrounding, physically separate cells. However, whereas this was previously interpreted to involve intercellular communication through TNTs, we found that Ca(2+) signal propagation was abolished - even in TNT-connected cells - after blocking ATP-mediated paracrine signaling with a cocktail of extracellular inhibitors. To then establish whether gap junctions may enable cell-cell signaling via TNTs under these conditions, we expressed sfGFP-tagged connexin-43 (Cx43) in HeLa M-Sec cells. We observed robust communication of mechanically-evoked Ca(2+) signals between distant but TNT-connected cells, but only when both cells expressed Cx43. Moreover, we also observed communication of Ca(2+) signals evoked in one cell by local photorelease of inositol 1,4,5-trisphosphate (IP3). Ca(2+) responses in connected cells began after long latencies at intracellular sites several microns from the TNT connection site, implicating intercellular transfer of IP3 and subsequent IP3-mediated Ca(2+) liberation, and not Ca(2+) itself, as the mediator between TNT-connected, Cx43-expressing cells. Our results emphasize the need to control for paracrine transmission in studies of cell-cell signaling via TNTs and indicate that, in this cell line, TNTs do not establish cytosolic continuity between connected cells but rather point to the crucial importance of connexins to enable communication of cytosolic Ca(2+) signals via TNTs.

  15. Inhibition does not affect the timing code for vocalizations in the mouse auditory midbrain

    Directory of Open Access Journals (Sweden)

    Alexander G Dimitrov

    2014-04-01

    Full Text Available Many animals use a diverse repertoire of complex acoustic signals to convey different types of information to other animals. The information in each vocalization therefore must be coded by neurons in the auditory system. One way in which the auditory system may discriminate among different vocalizations is by having highly selective neurons, where only one or two different vocalizations evoke a strong response from a single neuron. Another strategy is to have specific spike timing patterns for particular vocalizations such that each neural response can be matched to a specific vocalization. Both of these strategies may occur in the auditory midbrain of mice. However, the neural mechanisms underlying rate and time coding are unclear, but it is likely that inhibition plays a role. Here, we examined whether inhibition is involved in creating neural selectivity to vocalizations via rate and/or time coding in the mouse inferior colliculus. We examined extracellular single unit responses to vocalizations before and after iontophoretically blocking GABA_A and glycine receptors in the IC of awake mice. In general, we found that pharmacologically blocking inhibitory receptors in the IC increased response rate to vocalizations but did not dramatically affect spike timing. We observed two main effects when inhibition was locally blocked: 1 Highly selective neurons maintained their selectivity and the information about the stimuli did not change, but response rate increased slightly. 2 Neurons that responded to vocalizations in the control condition, also responded to the same stimuli in the test condition, with similar timing and pattern, but with a greater number of spikes, and, in some cases, greater reliability. Interestingly, in some neurons, blocking inhibition had no effect on vocalization-evoked responses. Overall, we found that inhibition in the IC does not play a substantial role in creating the reliable neuronal temporal patterns in response to

  16. Knee-clicks and visual traits indicate fighting ability in eland antelopes: multiple messages and back-up signals

    DEFF Research Database (Denmark)

    Bro-Jørgensen, Jakob; Dabelsteen, Torben

    2008-01-01

    Background: Given the costs of signalling, why do males often advertise their fighting ability to rivals using several signals rather than just one? Multiple signalling theories have developed largely in studies of sexual signals, and less is known about their applicability to intra-sexual commun...... of several selective forces, each of which favours multiple signals. Specifically, loud knee-clicking is discovered to be an honest signal of body size, providing an exceptional example of the potential for non-vocal acoustic communication in mammals....

  17. Vocal Cord Paralysis

    Science.gov (United States)

    ... your voice affects your ability to communicate. A speech therapist can help you develop the skills you need to communicate. Even if you're not able to regain the voice you once ... In addition, a speech-language pathologist can teach you efficient ways to ...

  18. From cues to signals: evolution of interspecific communication via aposematism and mimicry in a predator-prey system.

    Science.gov (United States)

    Lehmann, Kenna D S; Goldman, Brian W; Dworkin, Ian; Bryson, David M; Wagner, Aaron P

    2014-01-01

    Current theory suggests that many signaling systems evolved from preexisting cues. In aposematic systems, prey warning signals benefit both predator and prey. When the signal is highly beneficial, a third species often evolves to mimic the toxic species, exploiting the signaling system for its own protection. We investigated the evolutionary dynamics of predator cue utilization and prey signaling in a digital predator-prey system in which prey could evolve to alter their appearance to mimic poison-free or poisonous prey. In predators, we observed rapid evolution of cue recognition (i.e. active behavioral responses) when presented with sufficiently poisonous prey. In addition, active signaling (i.e. mimicry) evolved in prey under all conditions that led to cue utilization. Thus we show that despite imperfect and dishonest signaling, given a high cost of consuming poisonous prey, complex systems of interspecific communication can evolve via predator cue recognition and prey signal manipulation. This provides evidence supporting hypotheses that cues may serve as stepping-stones in the evolution of more advanced communication and signaling systems that incorporate information about the environment.

  19. From cues to signals: evolution of interspecific communication via aposematism and mimicry in a predator-prey system.

    Directory of Open Access Journals (Sweden)

    Kenna D S Lehmann

    Full Text Available Current theory suggests that many signaling systems evolved from preexisting cues. In aposematic systems, prey warning signals benefit both predator and prey. When the signal is highly beneficial, a third species often evolves to mimic the toxic species, exploiting the signaling system for its own protection. We investigated the evolutionary dynamics of predator cue utilization and prey signaling in a digital predator-prey system in which prey could evolve to alter their appearance to mimic poison-free or poisonous prey. In predators, we observed rapid evolution of cue recognition (i.e. active behavioral responses when presented with sufficiently poisonous prey. In addition, active signaling (i.e. mimicry evolved in prey under all conditions that led to cue utilization. Thus we show that despite imperfect and dishonest signaling, given a high cost of consuming poisonous prey, complex systems of interspecific communication can evolve via predator cue recognition and prey signal manipulation. This provides evidence supporting hypotheses that cues may serve as stepping-stones in the evolution of more advanced communication and signaling systems that incorporate information about the environment.

  20. Optical phase-locked loop signal sources for phased-array communications antennas

    Science.gov (United States)

    Langley, Lloyd N.; Edge, Colin; Wale, Michael J.; Gliese, Ulrik B.; Seeds, Alwyn J.; Walton, Channing; Wright, James G.; Coryell, Louis A.

    1997-10-01

    A coherent, optical heterodyne approach to signal generation and beamforming is particularly advantageous in multi-beam mobile phased arrays. Use of optical technology allows an optimum distribution of weight and power to be achieved between the antenna face and central electronics, together with an efficient implementation of the beamforming function and a modular design approach in which the basic building blocks are frequency-independent. Systems of this type employ a pair of optical carriers with a difference frequency equal to the required microwave signal. Phased- locking is necessary in order to achieve sufficiently low phase noise in the radio communication link. Optical phase locked loops (OPLLs) have been shown to be potential candidates for this application, yet work still needs to be done to bring them from the laboratory to field demonstrations. This paper describes the construction of a laser-diode OPLL subsystem for evaluation in a proof-of- concept beamforming system. This involves optimization of the loop design, development of single-frequency laser diodes with the correct linewidth, modulation and tuning characteristics and integration into a micro-optic assembly with custom wideband electronics.

  1. Coherent demodulation of microwave signals by using optical heterodyne technique with applications to point to point indoor wireless communications systems

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Juarez, A; Gomez-Colin, M R; Rojas-Hernandez, A G [Universidad de Sonora (Mexico); Zaldivar-Huerta, I E; Aguayo-Rodriguez, G [Instituto Nacional de Astrofisica, Optica y Electronica (Mexico); Rodriguez-Asomoza, J, E-mail: agarcia@cifus.uson.mx [Universidad de las Americas-Puebla (Mexico)

    2011-01-01

    An optical communications system using a couple microstrip antennas for distributing point to point analog TV with coherent demodulation based on optical heterodyne in close vicinity is reported in this paper. In the proposed experimental setup, two optical waves at different wavelengths are mixed and applied to a photodetector. Then a beat signal with a frequency equivalent to the spacing of the two wavelengths is obtained at the output of the photodetector. This signal corresponds to a microwave signal located at 1.25 GHz, which it is used as a microwave carrier in the transmitter and as a local oscillator in the receiver of our optical communication system. The feasibility of this technique is demonstrated transmitting a TV signal of 66-72 MHz.

  2. Long-Range Signaling in MutS and MSH Homologs via Switching of Dynamic Communication Pathways.

    Science.gov (United States)

    Wang, Beibei; Francis, Joshua; Sharma, Monika; Law, Sean M; Predeus, Alexander V; Feig, Michael

    2016-10-01

    Allostery is conformation regulation by propagating a signal from one site to another distal site. This study focuses on the long-range communication in DNA mismatch repair proteins MutS and its homologs where intramolecular signaling has to travel over 70 Å to couple lesion detection to ATPase activity and eventual downstream repair. Using dynamic network analysis based on extensive molecular dynamics simulations, multiple preserved communication pathways were identified that would allow such long-range signaling. The pathways appear to depend on the nucleotides bound to the ATPase domain as well as the type of DNA substrate consistent with previously proposed functional cycles of mismatch recognition and repair initiation by MutS and homologs. A mechanism is proposed where pathways are switched without major conformational rearrangements allowing for efficient long-range signaling and allostery.

  3. Coherent demodulation of microwave signals by using optical heterodyne technique with applications to point to point indoor wireless communications systems

    Science.gov (United States)

    García-Juárez, A.; Zaldívar-Huerta, I. E.; Aguayo-Rodríguez, G.; Rodríguez-Asomoza, J.; Gómez-Colín, M. R.; Rojas-Hernández, A. G.

    2011-01-01

    An optical communications system using a couple microstrip antennas for distributing point to point analog TV with coherent demodulation based on optical heterodyne in close vicinity is reported in this paper. In the proposed experimental setup, two optical waves at different wavelengths are mixed and applied to a photodetector. Then a beat signal with a frequency equivalent to the spacing of the two wavelengths is obtained at the output of the photodetector. This signal corresponds to a microwave signal located at 1.25 GHz, which it is used as a microwave carrier in the transmitter and as a local oscillator in the receiver of our optical communication system. The feasibility of this technique is demonstrated transmitting a TV signal of 66-72MHz.

  4. Animal Communication: What Do Animals Say?

    Science.gov (United States)

    Morton, Eugene S.

    1983-01-01

    Discusses the nature of animal communication, including possible relationships between the physical structure of vocalizations and their functions in communicating. Provides tables of mammalian and avian sounds (by species/family) used in hostile and friendly appeasing contexts. (JN)

  5. Testosterone and 11-ketotestosterone have different regulatory effects on electric communication signals of male Brachyhypopomus gauderio.

    Science.gov (United States)

    Goldina, Anna; Gavassa, Sat; Stoddard, Philip K

    2011-07-01

    The communication signals of electric fish can be dynamic, varying between the sexes on a circadian rhythm and in response to social and environmental cues. In the gymnotiform fish Brachyhypopomus gauderio waveform shape of the electric organ discharge (EOD) is regulated by steroid and peptide hormones. Furthermore, EOD amplitude and duration change on different timescales and in response to different social stimuli, suggesting that they are regulated by different mechanisms. Little is known about how androgen and peptide hormone systems interact to regulate signal waveform. We investigated the relationship between the androgens testosterone (T) and 11-ketotestosterone (11-KT), the melanocortin peptide hormone α-MSH, and their roles in regulating EOD waveform of male B. gauderio. Males were implanted with androgen (T, 11-KT, or blank), and injected with α-MSH before and at the peak of androgen effect. We compared the effects of androgen implants and social interactions by giving males a size-matched male stimulus with which they could interact electrically. Social stimuli and both androgens increased EOD duration, but only social stimuli and 11-KT elevated amplitude. However, no androgen enhanced EOD amplitude to the extent of a social stimulus, suggesting that a yet unidentified hormonal pathway regulates this signal parameter. Additionally, both androgens increased response of EOD duration to α-MSH, but only 11-KT increased response of EOD amplitude to α-MSH. Social stimuli had no effect on EOD response to α-MSH. The finding that EOD amplitude is preferentially regulated by 11-KT in B. gauderio may provide the basis for independent control of amplitude and duration.

  6. Booming far: the long-range vocal strategy of a lekking bird.

    Science.gov (United States)

    Cornec, C; Hingrat, Y; Aubin, T; Rybak, F

    2017-08-01

    The pressures of selection acting on transmission of information by acoustic signals are particularly high in long-distance communication networks. Males of the North African houbara bustard (Chlamydotis undulata undulata) produce extremely low-frequency vocalizations called 'booms' as a component of their courtship displays. These displays are performed on sites separated by a distance of on average 550 m, constituting exploded leks. Here, we investigate the acoustic features of booms involved in species-specific identity. We first assessed the modifications of acoustic parameters during boom transmission at long range within the natural habitat of the species, finding that the frequency content of booms was reliably transmitted up to 600 m. Additionally, by testing males' behavioural responses to playbacks of modified signals, we found that the presence of the second harmonic and the frequency modulation are the key parameters for species identification, and also that a sequence of booms elicited stronger responses than a single boom. Thus, the coding-decoding process relies on redundant and propagation-resistant features, making the booms particularly well adapted for the long-range transmission of information between males. Moreover, by experimentally disentangling the presentation of visual and acoustic signals, we showed that during the booming phase of courtship, the two sensory modalities act in synergy. The acoustic component is dominant in the context of intra-sexual competition. While the visual component is not necessary to induce agonistic response, it acts as an amplifier and reduces the time of detection of the signaller. The utilization of these adaptive strategies allows houbara males to maximize the active space of vocalizations emitted in exploded leks.

  7. The effects of physiological adjustments on the perceptual and acoustical characteristics of simulated laryngeal vocal tremor.

    Science.gov (United States)

    Lester, Rosemary A; Story, Brad H

    2015-08-01

    The purpose of this study was to determine if adjustments to the voice source [i.e., fundamental frequency (F0), degree of vocal fold adduction] or vocal tract filter (i.e., vocal tract shape for vowels) reduce the perception of simulated laryngeal vocal tremor and to determine if listener perception could be explained by characteristics of the acoustical modulations. This research was carried out using a computational model of speech production that allowed for precise control and manipulation of the glottal and vocal tract configurations. Forty-two healthy adults participated in a perceptual study involving pair-comparisons of the magnitude of "shakiness" with simulated samples of laryngeal vocal tremor. Results revealed that listeners perceived a higher magnitude of voice modulation when simulated samples had a higher mean F0, greater degree of vocal fold adduction, and vocal tract shape for /i/ vs /ɑ/. However, the effect of F0 was significant only when glottal noise was not present in the acoustic signal. Acoustical analyses were performed with the simulated samples to determine the features that affected listeners' judgments. Based on regression analyses, listeners' judgments were predicted to some extent by modulation information present in both low and high frequency bands.

  8. Design of Discrete Time Radio Receiver for the Demodulation of Power-Separated Co-Channel Satellite Communication Signals

    Science.gov (United States)

    2013-09-01

    video broadcasting [7]. ViaSat-1 (pictured in Figure 1), a high capacity Ka - band communications satellite went into service on 16 January 2012 as the...Video Broadcasting- satellite , Second Generation 8PSK 8- Phase Shift Keying GTED Gardner Timing Error Detector HP High Power signal, in layered...Spectral Density QPSK Quadrature Phase Shift Keying SCADA Supervisory Control and Data Acquisition SNR Signal to Noise Ratio SRRC Squared Raised

  9. Encoding of situations in the vocal repertoire of piglets (Sus scrofa): a comparison of discrete and graded classifications

    National Research Council Canada - National Science Library

    Tallet, Céline; Linhart, Pavel; Policht, Richard; Hammerschmidt, Kurt; Šimeček, Petr; Kratinova, Petra; Špinka, Marek

    2013-01-01

    .... The division of the vocal repertoire of piglets into two call types has previously been used in many experimental studies into pig acoustic communication and the five call types correspond well...

  10. Communication Modality Sampling for a Toddler with Angelman Syndrome

    Science.gov (United States)

    Martin, Jolene Hyppa; Reichle, Joe; Dimian, Adele; Chen, Mo

    2013-01-01

    Purpose: Vocal, gestural, and graphic communication modes were implemented concurrently with a toddler with Angelman syndrome to identify the most efficiently learned communication mode to emphasize in an initial augmentative communication system. Method: Symbols representing preferred objects were introduced in vocal, gestural, and graphic…

  11. Primate vocalization, gesture, and the evolution of human language.

    Science.gov (United States)

    Arbib, Michael A; Liebal, Katja; Pika, Simone

    2008-12-01

    The performance of language is multimodal, not confined to speech. Review of monkey and ape communication demonstrates greater flexibility in the use of hands and body than for vocalization. Nonetheless, the gestural repertoire of any group of nonhuman primates is small compared with the vocabulary of any human language and thus, presumably, of the transitional form called protolanguage. We argue that it was the coupling of gestural communication with enhanced capacities for imitation that made possible the emergence of protosign to provide essential scaffolding for protospeech in the evolution of protolanguage. Similarly, we argue against a direct evolutionary path from nonhuman primate vocalization to human speech. The analysis refines aspects of the mirror system hypothesis on the role of the primate brain's mirror system for manual action in evolution of the human language-ready brain.

  12. Influence of glycosaminoglycan identity on vocal fold fibroblast behavior.

    Science.gov (United States)

    Jimenez-Vergara, Andrea Carolina; Munoz-Pinto, Dany J; Becerra-Bayona, Silvia; Wang, Bo; Iacob, Alexandra; Hahn, Mariah S

    2011-11-01

    Poly(ethylene glycol) (PEG) hydrogels have recently begun to be studied for the treatment of scarred vocal fold lamina propria due, in part, to their tunable mechanical properties, resistance to fibroblast-mediated contraction, and ability to be polymerized in situ. However, pure PEG gels lack intrinsic biochemical signals to guide cell behavior and generally fail to mimic the frequency-dependent viscoelastic response critical to normal superficial lamina propria function. Recent results suggest that incorporation of viscoelastic bioactive substances, such as glycosaminoglycans (GAGs), into PEG networks may allow these gels to more closely approach the mechanical responses of normal vocal fold lamina propria while also stimulating desired vocal fold fibroblast behaviors. Although a number of vocal fold studies have examined the influence of hyaluronan (HA) on implant mechanics and vocal fold fibroblast responses, the effects of other GAG types have been relatively unexplored. This is significant, since recent studies have suggested that chondroitin sulfate C (CSC) and heparan sulfate (HS) are substantially altered in scarred lamina propria. The present study was therefore designed to evaluate the effects of CSC and HS incorporation on the mechanical response of PEG gels and vocal fold fibroblast behavior relative to HA. As with PEG-HA, the viscoelasticity of PEG-CSC and PEG-HS gels more closely approached that of the normal vocal fold lamina propria than pure PEG hydrogels. In addition, collagen I deposition and fibronectin production were significantly higher in CSC than in HA gels, and levels of the myofibroblast marker smooth muscle α-actin (SM α-actin) were greater in CSC and HS gels than in HA gels. Since collagen I, fibronectin, and SM α-actin are generally elevated in scarred lamina propria these results suggest that CSC and HS may be undesirable for vocal fold implants relative to HA. Investigation of various signaling intermediates indicated that

  13. Displays of paternal mouse pup retrieval following communicative interaction with maternal mates.

    Science.gov (United States)

    Liu, Hong-Xiang; Lopatina, Olga; Higashida, Chiharu; Fujimoto, Hiroko; Akther, Shirin; Inzhutova, Alena; Liang, Mingkun; Zhong, Jing; Tsuji, Takahiro; Yoshihara, Toru; Sumi, Kohei; Ishiyama, Mizuho; Ma, Wen-Jie; Ozaki, Mitsunori; Yagitani, Satoshi; Yokoyama, Shigeru; Mukaida, Naofumi; Sakurai, Takeshi; Hori, Osamu; Yoshioka, Katsuji; Hirao, Atsushi; Kato, Yukio; Ishihara, Katsuhiko; Kato, Ichiro; Okamoto, Hiroshi; Cherepanov, Stanislav M; Salmina, Alla B; Hirai, Hirokazu; Asano, Masahide; Brown, David A; Nagano, Isamu; Higashida, Haruhiro

    2013-01-01

    Compared with the knowledge of maternal care, much less is known about the factors required for paternal parental care. Here we report that new sires of laboratory mice, though not spontaneously parental, can be induced to show maternal-like parental care (pup retrieval) using signals from dams separated from their pups. During this interaction, the maternal mates emit 38-kHz ultrasonic vocalizations to their male partners, which are equivalent to vocalizations that occur following pheromone stimulation. Without these signals or in the absence of maternal mates, the sires do not retrieve their pups within 5 min. These results show that, in mice, the maternal parent communicates to the paternal parent to encourage pup care. This new paradigm may be useful in the analysis of the parental brain during paternal care induced by interactive communication.

  14. University Vocal Training and Vocal Health of Music Educators and Music Therapists

    Science.gov (United States)

    Baker, Vicki D.; Cohen, Nicki

    2017-01-01

    The purpose of this study was to describe the university vocal training and vocal health of music educators and music therapists. The participants (N = 426), music educators (n = 351) and music therapists (n = 75), completed a survey addressing demographics, vocal training, voice usage, and vocal health. Both groups reported singing at least 50%…

  15. Effect of reflected and refracted signals on coherent underwater acoustic communication: results from the Kauai experiment (KauaiEx 2003).

    Science.gov (United States)

    Rouseff, Daniel; Badiey, Mohsen; Song, Aijun

    2009-11-01

    The performance of a communications equalizer is quantified in terms of the number of acoustic paths that are treated as usable signal. The analysis uses acoustical and oceanographic data collected off the Hawaiian Island of Kauai. Communication signals were measured on an eight-element vertical array at two different ranges, 1 and 2 km, and processed using an equalizer based on passive time-reversal signal processing. By estimating the Rayleigh parameter, it is shown that all paths reflected by the sea surface at both ranges undergo incoherent scattering. It is demonstrated that some of these incoherently scattered paths are still useful for coherent communications. At range of 1 km, optimal communications performance is achieved when six acoustic paths are retained and all paths with more than one reflection off the sea surface are rejected. Consistent with a model that ignores loss from near-surface bubbles, the performance improves by approximately 1.8 dB when increasing the number of retained paths from four to six. The four-path results though are more stable and require less frequent channel estimation. At range of 2 km, ray refraction is observed and communications performance is optimal when some paths with two sea-surface reflections are retained.

  16. The effect of vocal tract impedance on the vocal folds

    DEFF Research Database (Denmark)

    Agerkvist, Finn T.; Selamtzis, Andreas

    2011-01-01

    , which is the mode that is most limited in pitch range, was tested at its pitch limit C5 (523 Hz) under normal conditions and when the singer has inhaled Helium. When inhaling Helium the acoustic impedance of the vocal tract is reduced in magnitude and the resonances are scaled upwards in frequency due...... to different density and speed of sound in Helium. The electroglottograph shows a change in waveform when the singer inhales helium. The percentage of the glottal cycle when the vocal cords are open, the so-called open quotient, increases from 40 to 55%. When inhaling helium the male singer was able reach Eb5...

  17. Food deprivation reduces and leptin increases the amplitude of an active sensory and communication signal in a weakly electric fish.

    Science.gov (United States)

    Sinnett, Philip M; Markham, Michael R

    2015-05-01

    Energetic demands of social communication signals can constrain signal duration, repetition, and magnitude. The metabolic costs of communication signals are further magnified when they are coupled to active sensory systems that require constant signal generation. Under such circumstances, metabolic stress incurs additional risk because energy shortfalls could degrade sensory system performance as well as the social functions of the communication signal. The weakly electric fish Eigenmannia virescens generates electric organ discharges (EODs) that serve as both active sensory and communication signals. These EODs are maintained at steady frequencies of 200-600Hz throughout the lifespan, and thus represent a substantial metabolic investment. We investigated the effects of metabolic stress (food deprivation) on EOD amplitude (EODa) and EOD frequency (EODf) in E. virescens and found that only EODa decreases during food deprivation and recovers after restoration of feeding. Cortisol did not alter EODa under any conditions, and plasma cortisol levels were not changed by food deprivation. Both melanocortin hormones and social challenges caused transient EODa increases in both food-deprived and well-fed fish. Intramuscular injections of leptin increased EODa in food-deprived fish but not well-fed fish, identifying leptin as a novel regulator of EODa and suggesting that leptin mediates EODa responses to metabolic stress. The sensitivity of EODa to dietary energy availability likely arises because of the extreme energetic costs of EOD production in E. virescens and also could reflect reproductive strategies of iteroparous species that reduce social signaling and reproduction during periods of stress to later resume reproductive efforts when conditions improve.

  18. Altered vocal fold kinematics in synthetic self-oscillating models that employ adipose tissue as a lateral boundary condition.

    Science.gov (United States)

    Saidi, Hiba; Erath, Byron D.

    2015-11-01

    The vocal folds play a major role in human communication by initiating voiced sound production. During voiced speech, the vocal folds are set into sustained vibrations. Synthetic self-oscillating vocal fold models are regularly employed to gain insight into flow-structure interactions governing the phonation process. Commonly, a fixed boundary condition is applied to the lateral, anterior, and posterior sides of the synthetic vocal fold models. However, physiological observations reveal the presence of adipose tissue on the lateral surface between the thyroid cartilage and the vocal folds. The goal of this study is to investigate the influence of including this substrate layer of adipose tissue on the dynamics of phonation. For a more realistic representation of the human vocal folds, synthetic multi-layer vocal fold models have been fabricated and tested while including a soft lateral layer representative of adipose tissue. Phonation parameters have been collected and are compared to those of the standard vocal fold models. Results show that vocal fold kinematics are affected by adding the adipose tissue layer as a new boundary condition.

  19. Discrimination of acoustic communication signals by grasshoppers (Chorthippus biguttulus): temporal resolution, temporal integration, and the impact of intrinsic noise.

    Science.gov (United States)

    Ronacher, Bernhard; Wohlgemuth, Sandra; Vogel, Astrid; Krahe, Rüdiger

    2008-08-01

    A characteristic feature of hearing systems is their ability to resolve both fast and subtle amplitude modulations of acoustic signals. This applies also to grasshoppers, which for mate identification rely mainly on the characteristic temporal patterns of their communication signals. Usually the signals arriving at a receiver are contaminated by various kinds of noise. In addition to extrinsic noise, intrinsic noise caused by stochastic processes within the nervous system contributes to making signal recognition a difficult task. The authors asked to what degree intrinsic noise affects temporal resolution and, particularly, the discrimination of similar acoustic signals. This study aims at exploring the neuronal basis for sexual selection, which depends on exploiting subtle differences between basically similar signals. Applying a metric, by which the similarities of spike trains can be assessed, the authors investigated how well the communication signals of different individuals of the same species could be discriminated and correctly classified based on the responses of auditory neurons. This spike train metric yields clues to the optimal temporal resolution with which spike trains should be evaluated. (c) 2008 APA, all rights reserved

  20. Vocal Fold Pathologies and Three-Dimensional Flow Separation Phenomena

    Science.gov (United States)

    Apostoli, Adam G.; Weiland, Kelley S.; Plesniak, Michael W.

    2013-11-01

    Polyps and nodules are two different pathologies, which are geometric abnormalities that form on the medial surface of the vocal folds, and have been shown to significantly disrupt a person's ability to communicate. Although the mechanism by which the vocal folds self-oscillate and the three-dimensional nature of the glottal jet has been studied, the effect of irregularities caused by pathologies is not fully understood. Examining the formation and evolution of vortical structures created by a geometric protuberance is important, not only for understanding the aerodynamic forces exerted by these structures on the vocal folds, but also in the treatment of the above-mentioned pathological conditions. Using a wall-mounted prolate hemispheroid with a 2:1 aspect ratio in cross flow, the present investigation considers three-dimensional flow separation induced by a model vocal fold polyp. Building on previous work using skin friction line visualization, both the velocity flow field and wall pressure measurements around the model polyp are presented and compared. Supported by the National Science Foundation, Grant No. CBET-1236351 and GW Center for Biomimetics and Bioinspired Engineering (COBRE).

  1. Envelhecimento vocal em idosos instucionalizados Vocal aging of institutionalized elderly people

    Directory of Open Access Journals (Sweden)

    Letícia Neiva de Menezes

    2007-03-01

    Full Text Available OBJETIVOS: avaliar de forma perceptivo-auditiva as características vocais de idosos institucionalizados, identificar se essas características interferem no processo de comunicação e correlacioná-las com a avaliação das estruturas do sistema estomatognático e do padrão de fala. MÉTODOS: estudo clínico do tipo transversal, no qual foram realizadas anamneses e avaliações fonoaudiológicas em uma amostra aleatória de 48 indivíduos idosos, residentes na Casa do Ancião Francisco Azevedo - Belo Horizonte/MG, que não apresentavam nenhum tipo de alteração neurológica, uma vez que, buscou-se traçar as manifestações fonoaudiológicas de idosos em processo de envelhecimento sadio. Utilizou-se protocolos específicos, desenvolvidos pelas autoras, de acordo com os aspectos pertinentes aos objetivos do presente estudo. RESULTADOS: na avaliação perceptivo-auditiva da qualidade vocal, constatou-se predominantemente qualidade vocal rouca (70,8%, em grau moderado (33,3%, loudness reduzida (56,2%, pitch grave (62,5% e tempos máximos de fonação reduzidos (81,2%. Dos 48 participantes, 85,4% relataram que a voz não interfere no processo de comunicação. Em relação aos padrões de fala, predominaram inteligibilidade preservada (83,3%, articulação preservada (72,9% e precisão articulatória preservada (83,3%. CONCLUSÕES: existem alterações nos parâmetros referentes à voz decorrentes da idade, sendo que elas não interferem na comunicação e mantêm relação diversa com outras mudanças nas estruturas do sistema estomatognático. Este estudo veio complementar as pesquisas na área de voz envolvendo indivíduos da terceira idade, sob processo de envelhecimento sadio e residentes em instituições de longa permanência.PURPOSES: to investigate vocal aspects related to healthy aging in the institutionalized elderly people, and to identify if these aspects interfer with communication and correlate vocal changes with motor oral system

  2. Optimum quantum receiver for detecting weak signals in PAM communication systems

    Science.gov (United States)

    Sharma, Navneet; Rawat, Tarun Kumar; Parthasarathy, Harish; Gautam, Kumar

    2017-09-01

    This paper deals with the modeling of an optimum quantum receiver for pulse amplitude modulator (PAM) communication systems. The information bearing sequence {I_k}_{k=0}^{N-1} is estimated using the maximum likelihood (ML) method. The ML method is based on quantum mechanical measurements of an observable X in the Hilbert space of the quantum system at discrete times, when the Hamiltonian of the system is perturbed by an operator obtained by modulating a potential V with a PAM signal derived from the information bearing sequence {I_k}_{k=0}^{N-1}. The measurement process at each time instant causes collapse of the system state to an observable eigenstate. All probabilities of getting different outcomes from an observable are calculated using the perturbed evolution operator combined with the collapse postulate. For given probability densities, calculation of the mean square error evaluates the performance of the receiver. Finally, we present an example involving estimating an information bearing sequence that modulates a quantum electromagnetic field incident on a quantum harmonic oscillator.

  3. Evidence for protonic communication at the speed of sound: An alternate mechanism for specific biological signaling

    CERN Document Server

    Fichtl, Bernhard; Schneider, Matthias F

    2015-01-01

    Local changes in pH are known to significantly alter the state and activity of proteins and in particular enzymes. pH variations induced by pulses propagating along soft interfaces (e.g. the lipid bilayer) would therefore constitute an important pillar towards a new physical mechanism of biochemical regulation and biological signaling. Here we investigate the pH-induced physical perturbation of a lipid interface and the physiochemical nature of the subsequent acoustic propagation. Pulses are stimulated by local acidification of a lipid monolayer and propagate, in analogy to sound, at velocities controlled by the two-dimensional compressibility of the interface. With transient local pH changes of 0.6 units directly observed at the interface and velocities up to 1.4 m/s this represents hitherto the fastest protonic communication observed. Furthermore simultaneously propagating mechanical and electrical changes in the lipid interface up to 8 mN/m and 100 mV are detected, exposing the thermodynamic nature of thes...

  4. Generalized perceptual features for animal vocalization classification

    Science.gov (United States)

    Clemins, Patrick J.; Johnson, Michael T.

    2001-05-01

    Two sets of generalized, perceptual-based features are investigated for use in classifying animal vocalizations. Since many species, especially mammals, share similar physical sound perception mechanisms which vary in size, two features sets commonly used in human speech processing, mel-frequency cepstral coefficients (MFCCs) and perceptual linear prediction (PLP) analysis, are modified for use in other species. One modification made to the feature extraction process is incorporating the frequency range of hearing and length of the basilar membrane of the animal in order to correctly determine the width and location of the critical band filters used for signal processing. Experimentally determined critical bands (equivalent rectangular bandwidth) and equal loudness curves (audiograms) can also be incorporated directly into the feature extraction process. Experiments are performed on African elephant (Loxodonta africana) vocalizations using a hidden Markov model (HMM) based classifier showing increased classification accuracy when using features sets based on the specific animals perceptual abilities compared to the original human perception-based feature sets.

  5. Microphone Array Signal Processing and Active Noise Control for the In-Helmet Speech Communication Project

    Data.gov (United States)

    National Aeronautics and Space Administration — For in-helmet voice communication, the currently used Communication-Cap-based Audio (CCA) systems have a number of recognized logistical issues and inconveniences...

  6. Biometric Methods for Secure Communications in Body Sensor Networks: Resource-Efficient Key Management and Signal-Level Data Scrambling

    Directory of Open Access Journals (Sweden)

    Dimitrios Hatzinakos

    2008-03-01

    Full Text Available As electronic communications become more prevalent, mobile and universal, the threats of data compromises also accordingly loom larger. In the context of a body sensor network (BSN, which permits pervasive monitoring of potentially sensitive medical data, security and privacy concerns are particularly important. It is a challenge to implement traditional security infrastructures in these types of lightweight networks since they are by design limited in both computational and communication resources. A key enabling technology for secure communications in BSN's has emerged to be biometrics. In this work, we present two complementary approaches which exploit physiological signals to address security issues: (1 a resource-efficient key management system for generating and distributing cryptographic keys to constituent sensors in a BSN; (2 a novel data scrambling method, based on interpolation and random sampling, that is envisioned as a potential alternative to conventional symmetric encryption algorithms for certain types of data. The former targets the resource constraints in BSN's, while the latter addresses the fuzzy variability of biometric signals, which has largely precluded the direct application of conventional encryption. Using electrocardiogram (ECG signals as biometrics, the resulting computer simulations demonstrate the feasibility and efficacy of these methods for delivering secure communications in BSN's.

  7. Biometric Methods for Secure Communications in Body Sensor Networks: Resource-Efficient Key Management and Signal-Level Data Scrambling

    Science.gov (United States)

    Bui, Francis Minhthang; Hatzinakos, Dimitrios

    2007-12-01

    As electronic communications become more prevalent, mobile and universal, the threats of data compromises also accordingly loom larger. In the context of a body sensor network (BSN), which permits pervasive monitoring of potentially sensitive medical data, security and privacy concerns are particularly important. It is a challenge to implement traditional security infrastructures in these types of lightweight networks since they are by design limited in both computational and communication resources. A key enabling technology for secure communications in BSN's has emerged to be biometrics. In this work, we present two complementary approaches which exploit physiological signals to address security issues: (1) a resource-efficient key management system for generating and distributing cryptographic keys to constituent sensors in a BSN; (2) a novel data scrambling method, based on interpolation and random sampling, that is envisioned as a potential alternative to conventional symmetric encryption algorithms for certain types of data. The former targets the resource constraints in BSN's, while the latter addresses the fuzzy variability of biometric signals, which has largely precluded the direct application of conventional encryption. Using electrocardiogram (ECG) signals as biometrics, the resulting computer simulations demonstrate the feasibility and efficacy of these methods for delivering secure communications in BSN's.

  8. Dual-channel telemetry system for recording vocalization-correlated neuronal activity in freely moving squirrel monkeys.

    Science.gov (United States)

    Grohrock, P; Häusler, U; Jürgens, U

    1997-09-05

    A miniature telemetric system is described which allows simultaneous measurements of neural activity and vocalization in freely moving monkeys within their social group. Single and multi-unit activities were detected with medium impedance electrodes that were fixed to self-made microdrives allowing accurate vertical positioning over a range of 8 mm. Vocalizations were registered by means of a piezo-ceramic device sensing the vocalization-induced skull vibrations. This allowed identification of the vocalizing animal in a larger group and eliminated environmental noise. Neuronal activity and vocalization were transmitted via separate channels of a FM transmitter using different carrier frequencies. The signals were decoded in two conventional FM receivers equipped with an automatic frequency control. The signals were stored for off-line analysis on a HiFi videotape recorder.

  9. Sex-specific responses to territorial intrusions in a communication network: Evidence from radio-tagged great tits.

    Science.gov (United States)

    Snijders, Lysanne; van Oers, Kees; Naguib, Marc

    2017-02-01

    Signals play a key role in the ecology and evolution of animal populations, influencing processes such as sexual selection and conflict resolution. In many species, sexually selected signals have a dual function: attracting mates and repelling rivals. Yet, to what extent males and females under natural conditions differentially respond to such signals remains poorly understood, due to a lack of field studies that simultaneously track both sexes. Using a novel spatial tracking system, we tested whether or not the spatial behavior of male and female great tits (Parus major) changes in relation to the vocal response of a territorial male neighbor to an intruder. We tracked the spatial behavior of male and female great tits (N = 44), 1 hr before and 1 hr after simulating territory intrusions, employing automatized Encounternet radio-tracking technology. We recorded the spatial and vocal response of the challenged males and quantified attraction and repulsion of neighboring males and females to the intrusion site. We additionally quantified the direct proximity network of the challenged male. The strength of a male's vocal response to an intruder induced sex-dependent movements in the neighborhood, via female attraction and male repulsion. Stronger vocal responders were older and in better body condition. The proximity networks of the male vocal responders, including the number of sex-dependent connections and average time spent with connections, however, did not change directly following the intrusion. The effects on neighbor movements suggest that the strength of a male's vocal response can provide relevant social information to both the males and the females in the neighborhood, resulting in both sexes adjusting their spatial behavior in contrasting ways, while the social proximity network remained stable. This study underlines the importance of "silent" eavesdroppers within communication networks for studying the dual functioning and evolution of sexually

  10. Communication Pattern Regarding Alarms and Patient Signals Between Nurses, Other Health Care Actors, Patients and Devices.

    Science.gov (United States)

    Solvoll, Terje; Hanenburg, Adrienne; Giordanego, Alain; Hartvigsen, Gunnar

    2015-01-01

    CallMeSmart is a context aware communication system for hospitals. The system is being used by nurses and the physicians at the Oncology department, University Hospital of North Norway. CallMeSmart has been designed to increase the efficiency of communication between the nurse-physician and physician-physician. In this study, we have looked at the communication pathways between nurse-nurse and patient-nurse: how nurses define a preference of calling somebody, how alarms and tasks are prioritized, and how this could be implemented into the CallMeSmart system to improve the system for the nurses. This paper discusses how the communication pathways of the patient alarm system can be improved for health care actors in hospitals by revealing the communication patterns according to an alarm between those actors. We address the communication pattern between nurses, other health care actors, patients and the devices used, and discuss possible improvements of this communication.

  11. Vocal Health for Physical Educators

    Science.gov (United States)

    Trout, Josh; McColl, Douglas

    2007-01-01

    Evidence suggests that teachers are often at risk for vocal disease and are more likely to change occupations because of their voice problems compared to non-teachers. Physical educators are especially at risk for voice problems due to the intense daily demands of voice projection. Chronic abuse can cause swelling and inflammation of the…

  12. A Maximum Likelihood Estimation of Vocal-Tract-Related Filter Characteristics for Single Channel Speech Separation

    Directory of Open Access Journals (Sweden)

    Mohammad H. Radfar

    2006-11-01

    Full Text Available We present a new technique for separating two speech signals from a single recording. The proposed method bridges the gap between underdetermined blind source separation techniques and those techniques that model the human auditory system, that is, computational auditory scene analysis (CASA. For this purpose, we decompose the speech signal into the excitation signal and the vocal-tract-related filter and then estimate the components from the mixed speech using a hybrid model. We first express the probability density function (PDF of the mixed speech's log spectral vectors in terms of the PDFs of the underlying speech signal's vocal-tract-related filters. Then, the mean vectors of PDFs of the vocal-tract-related filters are obtained using a maximum likelihood estimator given the mixed signal. Finally, the estimated vocal-tract-related filters along with the extracted fundamental frequencies are used to reconstruct estimates of the individual speech signals. The proposed technique effectively adds vocal-tract-related filter characteristics as a new cue to CASA models using a new grouping technique based on an underdetermined blind source separation. We compare our model with both an underdetermined blind source separation and a CASA method. The experimental results show that our model outperforms both techniques in terms of SNR improvement and the percentage of crosstalk suppression.

  13. A Maximum Likelihood Estimation of Vocal-Tract-Related Filter Characteristics for Single Channel Speech Separation

    Directory of Open Access Journals (Sweden)

    Dansereau Richard M

    2007-01-01

    Full Text Available We present a new technique for separating two speech signals from a single recording. The proposed method bridges the gap between underdetermined blind source separation techniques and those techniques that model the human auditory system, that is, computational auditory scene analysis (CASA. For this purpose, we decompose the speech signal into the excitation signal and the vocal-tract-related filter and then estimate the components from the mixed speech using a hybrid model. We first express the probability density function (PDF of the mixed speech's log spectral vectors in terms of the PDFs of the underlying speech signal's vocal-tract-related filters. Then, the mean vectors of PDFs of the vocal-tract-related filters are obtained using a maximum likelihood estimator given the mixed signal. Finally, the estimated vocal-tract-related filters along with the extracted fundamental frequencies are used to reconstruct estimates of the individual speech signals. The proposed technique effectively adds vocal-tract-related filter characteristics as a new cue to CASA models using a new grouping technique based on an underdetermined blind source separation. We compare our model with both an underdetermined blind source separation and a CASA method. The experimental results show that our model outperforms both techniques in terms of SNR improvement and the percentage of crosstalk suppression.

  14. Dynamic 3-D visualization of vocal tract shaping during speech.

    Science.gov (United States)

    Zhu, Yinghua; Kim, Yoon-Chul; Proctor, Michael I; Narayanan, Shrikanth S; Nayak, Krishna S

    2013-05-01

    Noninvasive imaging is widely used in speech research as a means to investigate the shaping and dynamics of the vocal tract during speech production. 3-D dynamic MRI would be a major advance, as it would provide 3-D dynamic visualization of the entire vocal tract. We present a novel method for the creation of 3-D dynamic movies of vocal tract shaping based on the acquisition of 2-D dynamic data from parallel slices and temporal alignment of the image sequences using audio information. Multiple sagittal 2-D real-time movies with synchronized audio recordings are acquired for English vowel-consonant-vowel stimuli /ala/, /a.ιa/, /asa/, and /a∫a/. Audio data are aligned using mel-frequency cepstral coefficients (MFCC) extracted from windowed intervals of the speech signal. Sagittal image sequences acquired from all slices are then aligned using dynamic time warping (DTW). The aligned image sequences enable dynamic 3-D visualization by creating synthesized movies of the moving airway in the coronal planes, visualizing desired tissue surfaces and tube-shaped vocal tract airway after manual segmentation of targeted articulators and smoothing. The resulting volumes allow for dynamic 3-D visualization of salient aspects of lingual articulation, including the formation of tongue grooves and sublingual cavities, with a temporal resolution of 78 ms.

  15. Genotoxic Potential of 1.6 GHz Wireless Communication Signal: In vivo Two-Year Bioassay

    Energy Technology Data Exchange (ETDEWEB)

    Vijayalaxmi, Vijay (University of Texas at San Antonio); Sasser, Lyle B.(SELF-EMPLOYED CONSULTANTS); Morris, J E.(GENERAL ELECTRIC CO.); Wilson, Bary W.(BATTELLE (PACIFIC NW LAB)); Anderson, Larry E.(SELF-EMPLOYED CONSULTANTS)

    2003-04-01

    Timed-pregnant Fischer 344 rats (from nineteenth day of gestation) and their nursing offspring (until weaning) were exposed to a far-field 1.6 GHz Iridium wireless communication signal for 2 h/day, 5 days/week. Far-field whole-body exposures were conducted with a field intensity of 0.43 mW/cm 2 and whole-body average specific absorption rate (SAR) of 0.036 to 0.077 W/kg (0.10 to 0.22 W/kg in the brain). This was followed by chronic, head-only exposures of male and female offspring to a near-field 1.6 GHz signal for 2 h/day, 5 days/week, over 2 years. Near-field exposures were conducted at an SAR of 0.16 or 1.6 W/kg in the brain. Concurrent sham-exposed and cage control rats were also included in the study. At the end of 2 years, all rats were necropsied. Bone marrow smears were examined for the extent of genotoxicity, assessed from the presence of micronuclei in polychromatic erythrocytes. The results indicated that the incidence of micronuclei/ 2000 polychromatic erythrocytes were not significantly different between 1.6 GHz-exposed, sham-exposed and cage control rats. The group mean frequencies were 5.6 6 1.8 (130 rats exposed to 1.6 GHz at 0.16 W/kg SAR), 5.4 6 1.5 (135 rats exposed to 1.6 GHz at 1.6 W/kg SAR), 5.6 6 1.7 (119 sham-exposed rats), and 5.8 6 1.8 (100 cage control rats). In contrast, positive control rats treated with mitomycin C exhibited significantly elevated incidence of micronuclei/2000 polychromatic erythrocytes in bone marrow cells; the mean frequency was 38.2 6 7.0 (five rats). Thus there was no evidence for excess genotoxicity in rats that were chronically exposed to 1.6 GHz compared to sham-exposed and cage controls.

  16. On how the brain decodes vocal cues about speaker confidence.

    Science.gov (United States)

    Jiang, Xiaoming; Pell, Marc D

    2015-05-01

    In speech communication, listeners must accurately decode vocal cues that refer to the speaker's mental state, such as their confidence or 'feeling of knowing'. However, the time course and neural mechanisms associated with online inferences about speaker confidence are unclear. Here, we used event-related potentials (ERPs) to examine the temporal neural dynamics underlying a listener's ability to infer speaker confidence from vocal cues during speech processing. We recorded listeners' real-time brain responses while they evaluated statements wherein the speaker's tone of voice conveyed one of three levels of confidence (confident, close-to-confident, unconfident) or were spoken in a neutral manner. Neural responses time-locked to event onset show that the perceived level of speaker confidence could be differentiated at distinct time points during speech processing: unconfident expressions elicited a weaker P2 than all other expressions of confidence (or neutral-intending utterances), whereas close-to-confident expressions elicited a reduced negative response in the 330-500 msec and 550-740 msec time window. Neutral-intending expressions, which were also perceived as relatively confident, elicited a more delayed, larger sustained positivity than all other expressions in the 980-1270 msec window for this task. These findings provide the first piece of evidence of how quickly the brain responds to vocal cues signifying the extent of a speaker's confidence during online speech comprehension; first, a rough dissociation between unconfident and confident voices occurs as early as 200 msec after speech onset. At a later stage, further differentiation of the exact level of speaker confidence (i.e., close-to-confident, very confident) is evaluated via an inferential system to determine the speaker's meaning under current task settings. These findings extend three-stage models of how vocal emotion cues are processed in speech comprehension (e.g., Schirmer & Kotz, 2006) by

  17. The Effects of Pitch Shifts on Delay-Induced Changes in Vocal Sequencing in a Songbird

    Science.gov (United States)

    Kelly, Conor W.

    2017-01-01

    Abstract Like human speech, vocal behavior in songbirds depends critically on auditory feedback. In both humans and songbirds, vocal skills are acquired by a process of imitation whereby current vocal production is compared to an acoustic target. Similarly, performance in adulthood relies strongly on auditory feedback, and online manipulations of auditory signals can dramatically alter acoustic production even after vocalizations have been well learned. Artificially delaying auditory feedback can disrupt both speech and birdsong, and internal delays in auditory feedback have been hypothesized as a cause of vocal dysfluency in persons who stutter. Furthermore, in both song and speech, online shifts of the pitch (fundamental frequency) of auditory feedback lead to compensatory changes in vocal pitch for small perturbations, but larger pitch shifts produce smaller changes in vocal output. Intriguingly, large pitch shifts can partially restore normal speech in some dysfluent speakers, suggesting that the effects of auditory feedback delays might be ameliorated by online pitch manipulations. Although birdsong provides a promising model system for understanding speech production, the interactions between sensory feedback delays and pitch shifts have not yet been assessed in songbirds. To investigate this, we asked whether the addition of a pitch shift modulates delay-induced changes in Bengalese finch song, hypothesizing that pitch shifts would reduce the effects of feedback delays. Compared with the effects of delays alone, combined delays and pitch shifts resulted in a significant reduction in behavioral changes in one type of sequencing (branch points) but not another (distribution of repeated syllables). PMID:28144622

  18. The Effects of Pitch Shifts on Delay-Induced Changes in Vocal Sequencing in a Songbird.

    Science.gov (United States)

    Wyatt, MacKenzie; Berthiaume, Emily A; Kelly, Conor W; Sober, Samuel J

    2017-01-01

    Like human speech, vocal behavior in songbirds depends critically on auditory feedback. In both humans and songbirds, vocal skills are acquired by a process of imitation whereby current vocal production is compared to an acoustic target. Similarly, performance in adulthood relies strongly on auditory feedback, and online manipulations of auditory signals can dramatically alter acoustic production even after vocalizations have been well learned. Artificially delaying auditory feedback can disrupt both speech and birdsong, and internal delays in auditory feedback have been hypothesized as a cause of vocal dysfluency in persons who stutter. Furthermore, in both song and speech, online shifts of the pitch (fundamental frequency) of auditory feedback lead to compensatory changes in vocal pitch for small perturbations, but larger pitch shifts produce smaller changes in vocal output. Intriguingly, large pitch shifts can partially restore normal speech in some dysfluent speakers, suggesting that the effects of auditory feedback delays might be ameliorated by online pitch manipulations. Although birdsong provides a promising model system for understanding speech production, the interactions between sensory feedback delays and pitch shifts have not yet been assessed in songbirds. To investigate this, we asked whether the addition of a pitch shift modulates delay-induced changes in Bengalese finch song, hypothesizing that pitch shifts would reduce the effects of feedback delays. Compared with the effects of delays alone, combined delays and pitch shifts resulted in a significant reduction in behavioral changes in one type of sequencing (branch points) but not another (distribution of repeated syllables).

  19. Decomposition of vocal cycle length perturbations into vocal jitter and vocal microtremor, and comparison of their size in normophonic speakers.

    Science.gov (United States)

    Schoentgen, J

    2003-06-01

    A statistical method that enables raw vocal cycle length perturbations to be decomposed into perturbations ascribed to vocal jitter and vocal tremor is presented, together with a comparison of the size of jitter and tremor. The method is based on a time series model that splits the vocal cycle length perturbations into uncorrelated cycle-to-cycle perturbations ascribed to vocal jitter and supra-cycle perturbations ascribed to vocal tremor. The corpus was composed of 114 vocal cycle length time series for sustained vowels [a], [i], and [u] produced by 22 male and 16 female normophonic speakers. The results were the following. First, 100 out of 114 time series were decomposed successfully by means of the time series model. Second, vocal perturbations ascribed to tremor were significantly larger than perturbations ascribed to jitter. Third, the correlation between vocal jitter and vocal tremor was moderate, but statistically significant. Fourth, small but statistically significant differences were observed among the three vowel timbres in the relative jitter and the arithmetic difference of jitter and tremor. Fifth, the differences between male and female speakers were not statistically significant in the relative raw perturbations, the relative jitter, or the modulation level owing to tremor.

  20. Measurement of vocal doses in virtual classrooms

    DEFF Research Database (Denmark)

    Bottalico, Pasquale; Pelegrin Garcia, David

    2010-01-01

    This work shows the results of a preliminary study about the determination of the optimal acoustical conditions for speakers in small classrooms. An experiment was carried out in a laboratory facility with 22 untrained talkers, who read a text passage from “Goldilocks” during two minutes under 13...... different acoustical conditions, that combined different kind of background noise and virtual classroom acoustics. Readings from the vocal fold vibrations were registered with an Ambulatory Phonation Monitor device. The speech signal from the talker in the center of the facility was picked up with a head......-worn microphone, convolved in real time with the impulse response of the chosen classroom, and reproduced through 29 loudspeakers placed around the subject. In particular, two different primary school classrooms were selected, with very low and very high reverberation time and, for each of them, two speaker...

  1. Morphological, olfactory, and vocal development in big brown bats

    Directory of Open Access Journals (Sweden)

    Heather W. Mayberry

    2014-12-01

    Full Text Available Using a within subjects design, we documented morphological, bioacoustical and behavioral developmental changes in big brown bats. Eptesicus fuscus pups are born naked and blind but assume an adult-like appearance by post-natal day (PND 45 and flight by PND 30. Adult females use spatial memory, acoustic and olfactory cues to reunite with offspring, but it is unclear if pups can recognize maternal scents. We tested the olfactory discrimination abilities of young E. fuscus pups and found they exhibited no odor preferences. Pups also emit distinct vocalizations called isolation calls (i-calls that facilitate mother-offspring reunions, but how pups shift their vocalizations from i-calls to downward frequency modulated (FM sweeps used in echolocation remains unclear. Between PND 0–9, pups emitted mainly long duration, tonal i-calls rich in harmonics, but after they switched to short duration, downward FM sweeps with fewer harmonics. Call maximum frequency and repetition rate showed minor changes across development. Signal duration, bandwidth, and number of harmonics decreased, whereas the maximum, minimum and bandwidth of the fundamental, and peak spectral frequency all increased. We recorded vocalizations during prolonged maternal separation and found that isolated pups called longer and at a faster rate, presumably to signal for maternal assistance. To assess how PND 13 pups alter their signals during interactions with humans we compared spontaneous and provoked vocalizations and found that provoked calls were spectrally and temporally more similar to those of younger bats suggesting that pups in distress emit signals that sound like younger bats to promote maternal assistance.

  2. Combined chemical and structural signals of biomaterials synergistically activate cell-cell communications for improving tissue regeneration.

    Science.gov (United States)

    Xu, Yachen; Peng, Jinliang; Dong, Xin; Xu, Yuhong; Li, Haiyan; Chang, Jiang

    2017-06-01

    Biomaterials are only used as carriers of cells in the conventional tissue engineering. Considering the multi-cell environment and active cell-biomaterial interactions in tissue regeneration process, in this study, structural signals of aligned electrospun nanofibers and chemical signals of bioglass (BG) ionic products in cell culture medium are simultaneously applied to activate fibroblast-endothelial co-cultured cells in order to obtain an improved skin tissue engineering construct. Results demonstrate that the combined biomaterial signals synergistically activate fibroblast-endothelial co-culture skin tissue engineering constructs through promotion of paracrine effects and stimulation of gap junctional communication between cells, which results in enhanced vascularization and extracellular matrix protein synthesis in the constructs. Structural signals of aligned electrospun nanofibers play an important role in stimulating both of paracrine and gap junctional communication while chemical signals of BG ionic products mainly enhance paracrine effects. In vivo experiments reveal that the activated skin tissue engineering constructs significantly enhance wound healing as compared to control. This study indicates the advantages of synergistic effects between different bioactive signals of biomaterials can be taken to activate communication between different types of cells for obtaining tissue engineering constructs with improved functions. Tissue engineering can regenerate or replace tissue or organs through combining cells, biomaterials and growth factors. Normally, for repairing a specific tissue, only one type of cells, one kind of biomaterials, and specific growth factors are used to support cell growth. In this study, we proposed a novel tissue engineering approach by simply using co-cultured cells and combined biomaterial signals. Using a skin tissue engineering model, we successfully proved that the combined biomaterial signals such as surface nanostructures

  3. Coupled Research in Ocean Acoustics and Signal Processing for the Next Generation of Underwater Acoustic Communication Systems

    Science.gov (United States)

    2016-08-05

    complexity of co- herent equalizer adaptation algorithms. This is joint work with MIT/WHOI Joint Program Student , Atulya Yellepeddi and is motivated by...communications signals, to achieve the specified improvements. The work this quarter focused on the continued development and analysis of an Expectation ...the Doppler shift of the direct arrival is essentially zero and the spread remains sta- ble at approximately 2.5 Hz with only a small rise at higher

  4. Is autoinducer-2 a universal signal for interspecies communication: a comparative genomic and phylogenetic analysis of the synthesis and signal transduction pathways

    Directory of Open Access Journals (Sweden)

    Wagner-Döbler Irene

    2004-09-01

    Full Text Available Abstract Background Quorum sensing is a process of bacterial cell-to-cell communication involving the production and detection of extracellular signaling molecules called autoinducers. Recently, it has been proposed that autoinducer-2 (AI-2, a furanosyl borate diester derived from the recycling of S-adenosyl-homocysteine (SAH to homocysteine, serves as a universal signal for interspecies communication. Results In this study, 138 completed genomes were examined for the genes involved in the synthesis and detection of AI-2. Except for some symbionts and parasites, all organisms have a pathway to recycle SAH, either using a two-step enzymatic conversion by the Pfs and LuxS enzymes or a one-step conversion using SAH-hydrolase (SahH. 51 organisms including most Gamma-, Beta-, and Epsilonproteobacteria, and Firmicutes possess the Pfs-LuxS pathway, while Archaea, Eukarya, Alphaproteobacteria, Actinobacteria and Cyanobacteria prefer the SahH pathway. In all 138 organisms, only the three Vibrio strains had strong, bidirectional matches to the periplasmic AI-2 binding protein LuxP and the central signal relay protein LuxU. The initial two-component sensor kinase protein LuxQ, and the terminal response regulator luxO are found in most Proteobacteria, as well as in some Firmicutes, often in several copies. Conclusions The genomic analysis indicates that the LuxS enzyme required for AI-2 synthesis is widespread in bacteria, while the periplasmic binding protein LuxP is only present in Vibrio strains. Thus, other organisms may either use components different from the AI-2 signal transduction system of Vibrio strains to sense the signal of AI-2, or they do not have such a quorum sensing system at all.

  5. A brain-computer interface for potential non-verbal facial communication based on EEG signals related to specific emotions.

    Science.gov (United States)

    Kashihara, Koji

    2014-01-01

    Unlike assistive technology for verbal communication, the brain-machine or brain-computer interface (BMI/BCI) has not been established as a non-verbal communication tool for amyotrophic lateral sclerosis (ALS) patients. Face-to-face communication enables access to rich emotional information, but individuals suffering from neurological disorders, such as ALS and autism, may not express their emotions or communicate their negative feelings. Although emotions may be inferred by looking at facial expressions, emotional prediction for neutral faces necessitates advanced judgment. The process that underlies brain neuronal responses to neutral faces and causes emotional changes remains unknown. To address this problem, therefore, this study attempted to decode conditioned emotional reactions to neutral face stimuli. This direction was motivated by the assumption that if electroencephalogram (EEG) signals can be used to detect patients' emotional responses to specific inexpressive faces, the results could be incorporated into the design and development of BMI/BCI-based non-verbal communication tools. To these ends, this study investigated how a neutral face associated with a negative emotion modulates rapid central responses in face processing and then identified cortical activities. The conditioned neutral face-triggered event-related potentials that originated from the posterior temporal lobe statistically significantly changed during late face processing (600-700 ms) after stimulus, rather than in early face processing activities, such as P1 and N170 responses. Source localization revealed that the conditioned neutral faces increased activity in the right fusiform gyrus (FG). This study also developed an efficient method for detecting implicit negative emotional responses to specific faces by using EEG signals. A classification method based on a support vector machine enables the easy classification of neutral faces that trigger specific individual emotions. In

  6. Some aspects of vocal fold bowing.

    Science.gov (United States)

    Tanaka, S; Hirano, M; Chijiwa, K

    1994-05-01

    Bowing of the vocal fold frequently occurs in patients with vocal fold paralysis (VFP), those with sulcus vocalis, and those who have had laser surgery. Additionally, there are vocal folds that present bowing with no noticeable organic lesion. For the purpose of investigating the causes and mechanisms of vocal fold bowing, consecutive fiberscopic videorecordings of 127 patients with VFP, 33 with sulcus vocalis, 33 with laser surgery, and 33 with dysphonia having no clinically noticeable organic lesion were reviewed. Sixty-nine percent of the paralyzed vocal folds had bowing, and the occurrence of bowing was significantly related to the activity of the thyroarytenoid muscle as measured by electromyography. The cricothyroid activity had no significant relationship to vocal fold bowing. All vocal folds with sulcus presented with bowing. Thirty-five percent of the vocal folds that had had laser surgery had bowing. The extent of tissue removal was closely related to the occurrence of bowing. Twelve cases with no organic lesion had vocal fold bowing. Of these 12 patients, 8 were male and 9 were older than 60 years. Some aging process in the mucosa was presumed to be the cause of the bowing in this age group of patients without clinically noticeable organic lesions. Causes of vocal fold bowing in the younger group of patients without organic lesions were not determined in this study.

  7. Long-distance multi-channel bidirectional chaos communication based on synchronized VCSELs subject to chaotic signal injection

    Science.gov (United States)

    Xie, Yi-Yuan; Li, Jia-Chao; He, Chao; Zhang, Zhen-Dong; Song, Ting-Ting; Xu, Chang-Jun; Wang, Gui-Jin

    2016-10-01

    A novel long-distance multi-channel bidirectional chaos communication system over multiple paths based on two synchronized 1550 nm vertical-cavity surface-emitting lasers (VCSELs) is proposed and studied theoretically. These two responding VCSELs (R-VCSELs) can output similar chaotic signals served as chaotic carrier in two linear polarization (LP) modes with identical signal injection from a driving VCSEL (D-VCSEL), which is subject to optical feedback and optical injection, simultaneously. Through the numerical simulations, high quality chaos synchronization between the two R-VCSELs can be obtained. Besides, the effects of varied qualities of chaos synchronization on communication performances in 20 km single mode fiber (SMF) channels are investigated by regulating different internal parameters mismatch after adopting chaos masking (CMS) technique. With the decrease of the maximum cross correlation coefficient (Max-C) between the two R-VCSELs, the bit error rate (BER) of decoded message increase. Meanwhile, the BER can still be less than 10-9 when the Max-C degrades to 0.982. Based on high quality synchronization, when the dispersion compensating fiber (DCF) links are introduced, 4n messages of 10 Gbit/s can transmit in 180 km SMF channels over n coupling paths, bidirectionally and simultaneously. Thorough tests are carried out with detailed analysis, demonstrating long-distance, multi-channel, bidirectional chaos communication based on VCSELs with chaotic signal injection.

  8. Teacher's voice: vocal tract discomfort symptoms, vocal intensity and noise in the classroom.

    Science.gov (United States)

    Mendes, Amanda Louize Félix; Lucena, Brunna Thaís Luckwu de; De Araújo, Aline Menezes Guedes Dias; Melo, Luciana Pimentel Fernandes de; Lopes, Leonardo Wanderley; Silva, Maria Fabiana Bonfim de Lima

    2016-04-01

    To identify a possible correlation between teachers vocal intensity and the noise in the classroom, as well as between vocal intensity and the symptoms of vocal tract discomfort before and after classes. 27 Elementary School I teachers participated in the study. We used the questionnaires "Vocal Production Condition of the Teacher" and "Vocal Tract Discomfort Scale - VTD" which were applied before and after the class. A properly calibrated noise meter was used for measuring noise in the classroom and the teachers' vocal intensity. There was a moderate positive correlation between vocal intensity and noise and also a significant difference between the VTD scale and the teachers with and without vocal complaint before and after classes. When compared separately on both occasions, there was an increase in the group's scores for both groups and with and without complaints. We found association of the vocal tract symptoms before and after classes, frequency of burning, itching, sore throat and sensitive throat were observed. The intensity of symptoms was significant for sore throat, itching and feeling of lump in the throat. We observed significant values of vocal intensity and frequency and intensity of symptoms for sensitive throat and lump in the throat before the class, and sore throat and lump in the throat after the. The increase in teacher's vocal intensity correlates to high noise levels in the classroom. The evidence suggests correlation between vocal intensity and discomfort of the vocal tract, with most of the symptoms reported in greater frequency and intensity after the class.

  9. The Development of Pointing Perception in Infancy: Effects of Communicative Signals on Covert Shifts of Attention

    Science.gov (United States)

    Daum, Moritz M.; Ulber, Julia; Gredebäck, Gustaf

    2013-01-01

    The present study aims to investigate the interplay of verbal and nonverbal communication with respect to infants' perception of pointing gestures. Infants were presented with still images of pointing hands (cue) in combination with an acoustic stimulus. The communicative content of this acoustic stimulus was varied from being human and…

  10. The Development of Pointing Perception in Infancy: Effects of Communicative Signals on Covert Shifts of Attention

    Science.gov (United States)

    Daum, Moritz M.; Ulber, Julia; Gredebäck, Gustaf

    2013-01-01

    The present study aims to investigate the interplay of verbal and nonverbal communication with respect to infants' perception of pointing gestures. Infants were presented with still images of pointing hands (cue) in combination with an acoustic stimulus. The communicative content of this acoustic stimulus was varied from being human and…

  11. VOCALS-UK: An overview of UK VOCALS science (Invited)

    Science.gov (United States)

    Coe, H.; Vocals-Uk Science Team

    2010-12-01

    This paper will highlight a variety of process studies, observationally led studies and modelling studies, both completed and in progress, conducted by groups in the United Kingdom, working in collaboration with international partners on the VAMOS Ocean-Cloud-Atmosphere Land Study Regional Experiment (VOCALS-REx). The VOCALS field experiment was conducted out of Arica, Chile, between October and November, 2008. The study aims to better understand the nature and variability of interactions between the ocean, atmosphere and steep topography, as well as local and long-range transport of pollutants and aerosol, in the context of their role in controlling the climate of the South East Pacific - an important region in terms of the global energy budget and which is currently poorly characterised in global climate models. Specific highlights will include a statistical representation of the SEP marine boundary layer during VOCALS-Rex to inform future modelling; an analysis of the synoptic and large-scale dynamical influences on cloud in the SEP; results from improved Met Office Unified Model forecast runs which examine aerosol-cloud interactions with a comparison to results from WRF-CHEM; and large eddy modelling of simulated gravity waves and their potential to induce open cellular convection (create pockets of open cells). In addition, early results from a number of further studies will be presented.

  12. Comportamento vocal de cantores populares Vocal behavior of popular singers

    Directory of Open Access Journals (Sweden)

    Valquíria Zimmer

    2012-04-01

    Full Text Available OBJETIVO: investigar aspectos do histórico, hábitos e comportamentos vocais de cantores populares, conforme o sexo e as categorias profissional e amador. MÉTODO: entrevista com 47 cantores, 25 homens e 22 mulheres. RESULTADOS: significância estatística nos seguintes achados: MASCULINO - microfone nos ensaios, ausência de problemas vocais diagnosticados, ausência de orientações sobre higiene vocal, dor ou desconforto após cantar, ausência de alergias e problemas respiratórios; FEMININO - aulas de canto e conhecimento sobre postura; AMADOR - não cantar dançando, não imitar vozes, ausência de avaliação otorrinolaringológica, ausência de problemas vocais diagnosticados, ausência de terapia fonoaudiológica, ausência de orientações de anatomofisiologia vocal e não utilização de álcool nos ensaios; PROFISSIONAL - rouquidão, conhecimento sobre articulação, álcool durante os shows, "garganta suja" ou pigarro, dor após cantar. CONCLUSÕES: a comparação entre os sexos evidenciou que os homens utilizavam microfone no ensaio, não apresentavam problemas alérgicos ou respiratórios, nem problemas vocais diagnosticados, mas apresentavam sensação de dor ou desconforto após o canto e não possuíam noções sobre higiene vocal; e que as mulheres realizavam aulas de canto e possuíam orientações de postura. A comparação entre amadores e profissionais mostrou que os amadores não cantavam dançando, não imitavam vozes, não utilizavam álcool nos ensaios, e não apresentavam problemas vocais diagnosticados, mas não possuíam avaliação otorrinolaringológica, não realizavam terapia fonoaudiológica, e não possuíam conhecimento sobre anatomofisiologia vocal; e os profissionais apresentavam queixa de rouquidão, de "garganta suja" ou pigarro e de dor após cantar, e usavam álcool durante os shows, apesar de possuir conhecimento sobre articulação.PURPOSE: to investigate aspects of vocal history, vocal habits and

  13. Singing modulates parvalbumin interneurons throughout songbird forebrain vocal control circuitry

    Science.gov (United States)

    Zengin-Toktas, Yildiz

    2017-01-01

    Across species, the performance of vocal signals can be modulated by the social environment. Zebra finches, for example, adjust their song performance when singing to females (‘female-directed’ or FD song) compared to when singing in isolation (‘undirected’ or UD song). These changes are salient, as females prefer the FD song over the UD song. Despite the importance of these performance changes, the neural mechanisms underlying this social modulation remain poorly understood. Previous work in finches has established that expression of the immediate early gene EGR1 is increased during singing and modulated by social context within the vocal control circuitry. Here, we examined whether particular neural subpopulations within those vocal control regions exhibit similar modulations of EGR1 expression. We compared EGR1 expression in neurons expressing parvalbumin (PV), a calcium buffer that modulates network plasticity and homeostasis, among males that performed FD song, males that produced UD song, or males that did not sing. We found that, overall, singing but not social context significantly affected EGR1 expression in PV neurons throughout the vocal control nuclei. We observed differences in EGR1 expression between two classes of PV interneurons in the basal ganglia nucleus Area X. Additionally, we found that singing altered the amount of PV expression in neurons in HVC and Area X and that distinct PV interneuron types in Area X exhibited different patterns of modulation by singing. These data indicate that throughout the vocal control circuitry the singing-related regulation of EGR1 expression in PV neurons may be less influenced by social context than in other neuron types and raise the possibility of cell-type specific differences in plasticity and calcium buffering. PMID:28235074

  14. Stomatal movement in response to long distance- communicated signals initiated by heat shock in partial roots of Commelina communis L.

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The systematic or long-distance signal transmission plays crucial roles in animal lives. Compared with animals, however, much less is known about the roles of long-distance signal communication in plant lives. Using the model plant Commelina communis L., we have probed the root to shoot communication mediated by heat-shock signals. The results showed that a heat shock of 5 min at 40℃ in partial roots, i.e. half or even 1/4 root system, could lead to a significant decrease in stomatal conductance. The regulation capability depends on both heat shock temperature and the amount of root system, i.e. with higher temperature and more roots stressed, the leaf conductance would decrease more significantly. Interestingly, the stomatal regulation by heat shock signal is in a manner of oscillation: when stomata conductance decreased to the lowest level within about 30 min, it would increase rapidly and sometimes even exceed the initial level, and after several cycles the stomata conductance would be finally stabilized at a lower level. Feeding xylem sap collected from heat-shocked plants could lead to a decrease in stomata conductance, suggesting that the heat shock-initiated signal is basically a positive signal. Further studies showed that heat shock was not able to affect ABA content in xylem sap, and also, not able to lead to a decrease in leaf water status, which suggested that the stomatal regulation was neither mediated by ABA nor by a hydraulic signal. Heat shock could lead to an increase in xylem sap H2O2 content, and moreover, the removal of H2O2 by catalase could partially recover the stomatal inhibition by xylem sap collected from heat-shocked plants, suggesting that H2O2 might be able to act as one of the root signals to control the stomatal movement. Due to the fact that heat-shock and drought are usually two concomitant stresses, the stomatal regulation by heat-shock signal should be of significance for plant response to stresses. The observation for the

  15. Communications

    Science.gov (United States)

    Bailenson, Jeremy; Buzzanell, Patrice; Deetz, Stanley; Tewksbury, David; Thompson, Robert J.; Turow, Joseph; Bichelmeyer, Barbara; Bishop, M. J.; Gayeski, Diane

    2013-01-01

    Scholars representing the field of communications were asked to identify what they considered to be the most exciting and imaginative work currently being done in their field, as well as how that work might change our understanding. The scholars included Jeremy Bailenson, Patrice Buzzanell, Stanley Deetz, David Tewksbury, Robert J. Thompson, and…

  16. Vocal improvement after voice therapy in the treatment of benign vocal fold lesions

    OpenAIRE

    Schindler, A; MOZZANICA, F.; Ginocchio, D.; MARUZZI, P.; Atac, M.; OTTAVIANI, F.

    2012-01-01

    SUMMARY Benign vocal fold lesions are common in the general population, and have important public health implications and impact on patient quality of life. Nowadays, phonomicrosurgery is the most common treatment of these lesions. Voice therapy is generally associated in order to minimize detrimental vocal behaviours that increase the stress at the mid-membranous vocal folds. Nonetheless, the most appropriate standard of care for treating benign vocal fold lesion has not been established. Th...

  17. Computational modeling of allosteric communication reveals organizing principles of mutation-induced signaling in ABL and EGFR kinases.

    Directory of Open Access Journals (Sweden)

    Anshuman Dixit

    2011-10-01

    Full Text Available The emerging structural information about allosteric kinase complexes and the growing number of allosteric inhibitors call for a systematic strategy to delineate and classify mechanisms of allosteric regulation and long-range communication that control kinase activity. In this work, we have investigated mechanistic aspects of long-range communications in ABL and EGFR kinases based on the results of multiscale simulations of regulatory complexes and computational modeling of signal propagation in proteins. These approaches have been systematically employed to elucidate organizing molecular principles of allosteric signaling in the ABL and EGFR multi-domain regulatory complexes and analyze allosteric signatures of the gate-keeper cancer mutations. We have presented evidence that mechanisms of allosteric activation may have universally evolved in the ABL and EGFR regulatory complexes as a product of a functional cross-talk between the organizing αF-helix and conformationally adaptive αI-helix and αC-helix. These structural elements form a dynamic network of efficiently communicated clusters that may control the long-range interdomain coupling and allosteric activation. The results of this study have unveiled a unifying effect of the gate-keeper cancer mutations as catalysts of kinase activation, leading to the enhanced long-range communication among allosterically coupled segments and stabilization of the active kinase form. The results of this study can reconcile recent experimental studies of allosteric inhibition and long-range cooperativity between binding sites in protein kinases. The presented study offers a novel molecular insight into mechanistic aspects of allosteric kinase signaling and provides a quantitative picture of activation mechanisms in protein kinases at the atomic level.

  18. Three-Dimensional Flow Separation Induced by a Model Vocal Fold Polyp

    Science.gov (United States)

    Stewart, Kelley C.; Erath, Byron D.; Plesniak, Michael W.

    2012-11-01

    The fluid-structure energy exchange process for normal speech has been studied extensively, but it is not well understood for pathological conditions. Polyps and nodules, which are geometric abnormalities that form on the medial surface of the vocal folds, can disrupt vocal fold dynamics and thus can have devastating consequences on a patient's ability to communicate. A recent in-vitro investigation of a model polyp in a driven vocal fold apparatus demonstrated that such a geometric abnormality considerably disrupts the glottal jet behavior and that this flow field adjustment was a likely reason for the severe degradation of the vocal quality in patients. Understanding of the formation and propagation of vortical structures from a geometric protuberance, and their subsequent impact on the aerodynamic loadings that drive vocal fold dynamic, is a critical component in advancing the treatment of this pathological condition. The present investigation concerns the three-dimensional flow separation induced by a wall-mounted prolate hemispheroid with a 2:1 aspect ratio in cross flow, i.e. a model vocal fold polyp. Unsteady three-dimensional flow separation and its impact of the wall pressure loading are examined using skin friction line visualization and wall pressure measurements. Supported by the National Science Foundation, Grant No. CBET-1236351 and GW Center for Biomimetics and Bioinspired Engineering (COBRE).

  19. Noradrenergic control of gene expression and long-term neuronal adaptation evoked by learned vocalizations in songbirds.

    Directory of Open Access Journals (Sweden)

    Tarciso A F Velho

    Full Text Available Norepinephrine (NE is thought to play important roles in the consolidation and retrieval of long-term memories, but its role in the processing and memorization of complex acoustic signals used for vocal communication has yet to be determined. We have used a combination of gene expression analysis, electrophysiological recordings and pharmacological manipulations in zebra finches to examine the role of noradrenergic transmission in the brain's response to birdsong, a learned vocal behavior that shares important features with human speech. We show that noradrenergic transmission is required for both the expression of activity-dependent genes and the long-term maintenance of stimulus-specific electrophysiological adaptation that are induced in central auditory neurons by stimulation with birdsong. Specifically, we show that the caudomedial nidopallium (NCM, an area directly involved in the auditory processing and memorization of birdsong, receives strong noradrenergic innervation. Song-responsive neurons in this area express α-adrenergic receptors and are in close proximity to noradrenergic terminals. We further show that local α-adrenergic antagonism interferes with song-induced gene expression, without affecting spontaneous or evoked electrophysiological activity, thus dissociating the molecular and electrophysiological responses to song. Moreover, α-adrenergic antagonism disrupts the maintenance but not the acquisition of the adapted physiological state. We suggest that the noradrenergic system regulates long-term changes in song-responsive neurons by modulating the gene expression response that is associated with the electrophysiological activation triggered by song. We also suggest that this mechanism may be an important contributor to long-term auditory memories of learned vocalizations.

  20. Aesthetic and Culture Origin of Vocal Art

    Institute of Scientific and Technical Information of China (English)

    张延春

    2010-01-01

    As one of the most commonly and widely adopted art forms, vocal art has been closely related with national culture and the aesthetics trend. Traditional Chinese vocal art rooted from China' s long history and distinctive culture. On the contrary, Italian bel canto stems from the prospect of Italian Opera Art during the Renaissance period. This essay discusses the differences between East and West vocal art, from its aesthetic and culture origin.

  1. Reference in human and non-human primate communication: What does it take to refer?

    Science.gov (United States)

    Sievers, Christine; Gruber, Thibaud

    2016-07-01

    The concept of functional reference has been used to isolate potentially referential vocal signals in animal communication. However, its relatedness to the phenomenon of reference in human language has recently been brought into question. While some researchers have suggested abandoning the concept of functional reference altogether, others advocate a revision of its definition to include contextual cues that play a role in signal production and perception. Empirical and theoretical work on functional reference has also put much emphasis on how the receiver understands the referential signal. However, reference, as defined in the linguistic literature, is an action of the producer, and therefore, any definition describing reference in non-human animals must also focus on the producer. To successfully determine whether a signal is used to refer, we suggest an approach from the field of pragmatics, taking a closer look at specific situations of signal production, specifically at the factors that influence the production of a signal by an individual. We define the concept of signaller's reference to identify intentional acts of reference produced by a signaller independently of the communicative modality, and illustrate it with a case study of the hoo vocalizations produced by wild chimpanzees during travel. This novel framework introduces an intentional approach to referentiality. It may therefore permit a closer comparison of human and non-human animal referential behaviour and underlying cognitive processes, allowing us to identify what may have emerged solely in the human lineage.

  2. Sonic Hedgehog Signaling Mediates Epithelial–Mesenchymal Communication and Promotes Renal Fibrosis

    OpenAIRE

    Ding, Hong; Zhou, Dong; Hao, Sha; Zhou, Lili; He, Weichun; Nie, Jing; Hou, Fan Fan; Liu, Youhua

    2012-01-01

    Sonic hedgehog (Shh) signaling is a developmental signal cascade that plays an essential role in regulating embryogenesis and tissue homeostasis. Here, we investigated the potential role of Shh signaling in renal interstitial fibrogenesis. Ureteral obstruction induced Shh, predominantly in the renal tubular epithelium of the fibrotic kidneys. Using Gli1lacZ knock-in mice, we identified renal interstitial fibroblasts as Shh-responding cells. In cultured renal fibroblasts, recombinant Shh prote...

  3. Oral and vocal fold diadochokinesis in dysphonic women

    Directory of Open Access Journals (Sweden)

    Talita Louzada

    2011-12-01

    Full Text Available The evaluation of oral and vocal fold diadochokinesis (DDK in individuals with voice disorders may contribute to the understanding of factors that affect the balanced vocal production. Scientific studies that make use of this assessment tool support the knowledge advance of this area, reflecting the development of more appropriate therapeutic planning. Objective: To compare the results of oral and vocal fold DDK in dysphonic women and in women without vocal disorders. Material and methods: For this study, 28 voice recordings of women from 19 to 54 years old, diagnosed with dysphonia and submitted to a voice assessment from speech pathologist and otorhinolaryngologist, were used. The control group included 30 nondysphonic women evaluated in prior research from normal adults. The analysis parameters like number and duration of emissions, as well as the regularity of the repetition of syllables "pa", "ta", "ka" and the vowels "a" and "i," were provided by the Advanced Motor Speech Profile program (MSP Model-5141, version-2.5.2 (KayPentax. The DDK sequence "pataka" was analyzed quantitatively through the Sound Forge 7.0 program, as well as manually with the audio-visual help of sound waves. Average values of oral and vocal fold DDK dysphonic and nondysphonic women were compared using the "t Student" test and were considered significant when p<0.05. Results: The findings showed no significant differences between populations; however, the coefficient of variation of period (CvP and jitter of period (JittP average of the "ka," "a" and "i" emissions, respectively, were higher in dysphonic women (CvP=10.42%, 12.79%, 12.05%; JittP=2.05%, 6.05%, 3.63% compared to the control group (CvP=8.86%; 10.95%, 11.20%; JittP=1.82%, 2.98%, 3.15%. Conclusion: Although the results do not indicate any difficulties in oral and laryngeal motor control in the dysphonic group, the largest instability in vocal fold DDK in the experimental group should be considered, and

  4. Cell-to-cell communication in intact taste buds through ATP signalling from pannexin 1 gap junction hemichannels.

    Science.gov (United States)

    Dando, Robin; Roper, Stephen D

    2009-12-15

    Isolated taste cells, taste buds and strips of lingual tissue from taste papillae secrete ATP upon taste stimulation. Taste bud receptor (Type II) cells have been identified as the source of ATP secretion. Based on studies on isolated taste buds and single taste cells, we have postulated that ATP secreted from receptor cells via pannexin 1 hemichannels acts within the taste bud to excite neighbouring presynaptic (Type III) cells. This hypothesis, however, remains to be tested in intact tissues. In this report we used confocal Ca(2+) imaging and lingual slices containing intact taste buds to test the hypothesis of purinergic signalling between taste cells in a more integral preparation. Incubating lingual slices with apyrase reversibly blocked cell-to-cell communication between receptor cells and presynaptic cells, consistent with ATP being the transmitter. Inhibiting pannexin 1 gap junction hemichannels with CO(2)-saturated buffer or probenecid significantly reduced cell-cell signalling between receptor cells and presynaptic cells. In contrast, anandamide, a blocker of connexin gap junction channels, had no effect of cell-to-cell communication in taste buds. These findings are consistent with the model for peripheral signal processing via ATP and pannexin 1 hemichannels in mammalian taste buds.

  5. The Linked Dual Representation model of vocal perception and production

    Directory of Open Access Journals (Sweden)

    Sean eHutchins

    2013-11-01

    Full Text Available The voice is one of the most important media for communication, yet there is a wide range of abilities in both the perception and production of the voice. In this article, we review this range of abilities, focusing on pitch accuracy as a particularly informative case, and look at the factors underlying these abilities. Several classes of models have been posited describing the relationship between vocal perception and production, and we review the evidence for and against each class of model. We look at how the voice is different from other musical instruments and review evidence about both the association and the dissociation between vocal perception and production abilities. Finally, we introduce the Linked Dual Representation model, a new approach which can account for the broad patterns in prior findings, including trends in the data which might seem to be countervailing. We discuss how this model interacts with higher-order cognition and examine its predictions about several aspects of vocal perception and production.

  6. The Role of Positive and Negative Signaling Communication by Strong and Weak Ties in the Shaping of Safe Sex Subjective Norms of Adolescents in South Africa

    NARCIS (Netherlands)

    Boer, H.; Westhoff, Yvette

    2006-01-01

    We propose the theory that subjective (injunctive) social norms are shaped through two intertwined processes: positive and negative signaling communication by the personal social network and construal of the communicated social norm. Construal is evoked by the strength of the relation between a tie

  7. Parameter estimation of DSSS signals in non-cooperative communication system

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaoming; Zhang Zhongzhao

    2007-01-01

    A new adaptive estimator for direct sequence spread spectrum (DSSS) signals using fourth-order cumulant based adaptive method is considered. The general higher-order statistics may not be easily applied in signal processing with too complex computation. Based on the fourth-order cumulant with 1-D slices and adaptive filters, an efficient algorithm is proposed to solve the problem and is extended for nonstationary stochastic processes. In order to achieve thc accurate parameter estimation of direct sequence spread spectrum (DSSS) signals, the firrst step uses the modified fourth-order cumulant to reduce the computing complexity. While the second step employs an adaptive recursive system to estimate the power spectrum in the frequency domain. In the case of intercepted signals without large enough data samples, the estimator provides good performance in parameter estimation and white Gaussian noise suppression. Computer simulations are included to corroborate the theoretical development with different signal-to-noise ratio conditions and recursive coefficients.

  8. Individual, unit and vocal clan level identity cues in sperm whale codas

    DEFF Research Database (Denmark)

    Gero, Shane; Whitehead, Hal; Rendell, Luke

    2016-01-01

    The ‘social complexity hypothesis’ suggests that complex social structure is a driver of diversity in animal communication systems. Sperm whales have a hierarchically structured society in which the largest affiliative structures, the vocal clans, are marked on ocean-basin scales by culturally tr...

  9. Low probability of intercept-based adaptive radar waveform optimization in signal-dependent clutter for joint radar and cellular communication systems

    Science.gov (United States)

    Shi, Chenguang; Salous, Sana; Wang, Fei; Zhou, Jianjiang

    2016-12-01

    In this paper, we investigate the problem of low probability of intercept (LPI)-based adaptive radar waveform optimization in signal-dependent clutter for joint radar and cellular communication systems, where the radar system optimizes the transmitted waveform such that the interference caused to the cellular communication systems is strictly controlled. Assuming that the precise knowledge of the target spectra, the power spectral densities (PSDs) of signal-dependent clutters, the propagation losses of corresponding channels and the communication signals is known by the radar, three different LPI based criteria for radar waveform optimization are proposed to minimize the total transmitted power of the radar system by optimizing the multicarrier radar waveform with a predefined signal-to-interference-plus-noise ratio (SINR) constraint and a minimum required capacity for the cellular communication systems. These criteria differ in the way the communication signals scattered off the target are considered in the radar waveform design: (1) as useful energy, (2) as interference or (3) ignored altogether. The resulting problems are solved analytically and their solutions represent the optimum power allocation for each subcarrier in the multicarrier radar waveform. We show with numerical results that the LPI performance of the radar system can be significantly improved by exploiting the scattered echoes off the target due to cellular communication signals received at the radar receiver.

  10. Audio-vocal responses of vocal fundamental frequency and formant during sustained vowel vocalizations in different noises.

    Science.gov (United States)

    Lee, Shao-Hsuan; Hsiao, Tzu-Yu; Lee, Guo-She

    2015-06-01

    Sustained vocalizations of vowels [a], [i], and syllable [mə] were collected in twenty normal-hearing individuals. On vocalizations, five conditions of different audio-vocal feedback were introduced separately to the speakers including no masking, wearing supra-aural headphones only, speech-noise masking, high-pass noise masking, and broad-band-noise masking. Power spectral analysis of vocal fundamental frequency (F0) was used to evaluate the modulations of F0 and linear-predictive-coding was used to acquire first two formants. The results showed that while the formant frequencies were not significantly shifted, low-frequency modulations (production, the motor speech controls on F0 may depend on a feedback mechanism while articulation should rely more on a feedforward mechanism. Power spectral analysis of F0 might be applied to evaluate audio-vocal control for various hearing and neurological disorders in the future. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. COMMUNICATIONS

    CERN Document Server

    A. Petrilli

    2013-01-01

    The organisation of the Open Days at the end of September was the single biggest effort of the CMS Communications Group this year. We would like to thank all volunteers for their hard work to show our Point 5 facilities and explain science and technology to the general public. During two days more than 5,000 people visited the CMS detector underground and profited from the surface activities, which included an exhibition on CMS, a workshop on superconductivity, and an activity for our younger visitors involving wooden Kapla blocks. The Communications Group took advantage of the preparations to produce new CMS posters that can be reused at other venues. Event display images have been produced not just for this occasion but also for other exhibits, education purposes, publications etc. During the Open Days, Gilles Jobin, 2012 winner of CERN Collide@CERN prize, performed his Quantum show in Point 5, with the light installation of German artist Julius von Bismarck. Image 3: CERN Open Days at CMS wel...

  12. COMMUNICATIONS

    CERN Multimedia

    L. Taylor and D. Barney

    2010-01-01

    CMS Centres, Outreach and the 7 TeV Media Event The new CMS Communications group is now established and is addressing three areas that are critical to CMS as it enters the physics operations phase: - Communications Infrastructure, including almost 50 CMS Centres Worldwide, videoconferencing systems, and CERN meeting rooms - Information systems, including the internal and external Web sites as well as the document preparation and management systems - Outreach and Education activities, including working with print, radio and TV media, visits to CMS, and exhibitions. The group has been active in many areas, with the highest priority being accorded to needs of CMS operations and preparations for the major media event planned for 7 TeV collisions. Unfortunately the CMS Centre@CERN suffered a major setback when, on 21st December, a cooling water pipe froze and burst on the floor above the CMS Centre main room. Water poured through the ceiling, flooding the floor and soaking some of the consoles, before e...

  13. Finding the beat: From socially coordinated vocalizations in songbirds to rhythmic entrainment in humans.

    Directory of Open Access Journals (Sweden)

    Jonathan Isaac Benichov

    2016-06-01

    Full Text Available Humans and oscine songbirds share the rare capacity for vocal learning. Songbirds have the ability to acquire songs and calls of various rhythms through imitation. In several species, birds can even coordinate the timing of their vocalizations with other individuals in duets that are synchronized with millisecond-accuracy. It is not known, however, if songbirds can perceive rhythms holistically nor if they are capable of spontaneous entrainment to complex rhythms, in a manner similar to humans. Here we review emerging evidence from studies of rhythm generation and vocal coordination across songbirds and humans. In particular, recently developed experimental methods have revealed neural mechanisms underlying the temporal structure of song and have allowed us to test birds’ abilities to predict the timing of rhythmic social signals. Surprisingly, zebra finches can readily learn to anticipate the calls of a vocal robot partner and alter the timing of their answers to avoid jamming, even in reference to complex rhythmic patterns. This capacity resembles, to some extent, human predictive motor response to an external beat. In songbirds, this is driven, at least in part, by the forebrain song system, which controls song timing and is essential for vocal learning. Building upon previous evidence for spontaneous entrainment in human and non-human vocal learners, we propose a comparative framework for future studies aimed at identifying shared mechanism of rhythm production and perception across songbirds and humans.

  14. Does age matter in song bird vocal interactions? Results from interactive playback experiments

    Directory of Open Access Journals (Sweden)

    Kiefer Sarah

    2011-11-01

    Full Text Available Abstract The song of oscines provides an extensively studied model of age-dependent behaviour changes. Male and female receivers might use song characteristics to obtain information about the age of a signaller, which is often related to its quality. Whereas most of the age-dependent song changes have been studied in solo singing, the role of age in vocal interactions is less well understood. We addressed this issue in a playback study with common nightingales (Luscinia megarhynchos. Previous studies showed that male nightingales had smaller repertoires in their first year than older males and males adjusted their repertoire towards the most common songs in the breeding population. We now compared vocal interaction patterns in a playback study in 12 one year old and 12 older nightingales (cross-sectional approach. Five of these males were tested both in their first and second breeding season (longitudinal approach. Song duration and latency to respond did not differ between males of different ages in either approach. In the cross-sectional approach, one year old nightingales matched song types twice as often as did older birds. Similarly, in the longitudinal approach all except one bird reduced the number of song type matches in their second season. Individuals tended to overlap songs at higher rates in their second breeding season than in their first. The higher levels of song type matches in the first year and song overlapping by birds in their second year suggest that these are communicative strategies to establish relationships with competing males and/or choosy females.

  15. Optimal space communications techniques. [discussion of video signals and delta modulation

    Science.gov (United States)

    Schilling, D. L.

    1974-01-01

    The encoding of video signals using the Song Adaptive Delta Modulator (Song ADM) is discussed. The video signals are characterized as a sequence of pulses having arbitrary height and width. Although the ADM is suited to tracking signals having fast rise times, it was found that the DM algorithm (which permits an exponential rise for estimating an input step) results in a large overshoot and an underdamped response to the step. An overshoot suppression algorithm which significantly reduces the ringing while not affecting the rise time is presented along with formuli for the rise time and the settling time. Channel errors and their effect on the DM encoded bit stream were investigated.

  16. When the brain speaks for itself : exploiting hemodynamic brain signals for motor-independent communication

    NARCIS (Netherlands)

    Sorger, B.

    2010-01-01

    Communication is an essential element of human interaction but can be compromised in several clinical conditions. In the so-called 'locked-in' syndrome (LIS), resulting from a severe motor paralysis, patients are literally confined to their own bodies, while at the same time being fully conscious an

  17. When the brain speaks for itself : exploiting hemodynamic brain signals for motor-independent communication

    NARCIS (Netherlands)

    Sorger, B.

    2010-01-01

    Communication is an essential element of human interaction but can be compromised in several clinical conditions. In the so-called 'locked-in' syndrome (LIS), resulting from a severe motor paralysis, patients are literally confined to their own bodies, while at the same time being fully conscious

  18. First Communion: The Emergence of Vocal Relationships.

    Science.gov (United States)

    Locke, John L.

    2001-01-01

    Proposes that vocal communion between infant and caregiver supports infants' language acquisition and connectedness with caregivers. Recommends research to determine whether social behaviors such as joint attention and vocal imitation are functionally related to language learning or are only symptomatic of a survival-centered caregiving…

  19. Pulmonary mucormycosis presenting with vocal cord paralysis

    OpenAIRE

    Gayathri Devi, H. J.; Mohan Rao, K.N.; K M Prathima; Moideen, Riyaz

    2013-01-01

    Pulmonary mucormycosis is a relatively uncommon infection. It can present in various forms. Very few cases of pulmonary mucormycosis presenting as vocal cord paralysis have been described in the literature. We report a case of pulmonary mucormycosis presenting as vocal cord paralysis in an uncontrolled diabetic patient.

  20. Phonetic characteristics of vocalizations during pain

    Directory of Open Access Journals (Sweden)

    Stefan Lautenbacher

    2017-06-01

    Conclusion:. Vocalization characteristics of pain seem to be best described by an increase in pitch and in loudness. Future studies using more specific and comprehensive phonetic analyses will surely help to provide an even more precise characterization of vocalizations because of pain.

  1. A Quantitative Analysis of Pulsed Signals Emitted by Wild Bottlenose Dolphins

    National Research Council Canada - National Science Library

    Luís, Ana Rita; Couchinho, Miguel N; Dos Santos, Manuel E

    2016-01-01

    Common bottlenose dolphins (Tursiops truncatus), produce a wide variety of vocal emissions for communication and echolocation, of which the pulsed repertoire has been the most difficult to categorize...

  2. Time domain zero-padding based adaptive-PAM signal transmission with high spectral efficiency in IMDD optical communication system

    Science.gov (United States)

    Zhang, Fangliu; He, Jing; Deng, Rui; Cheng, Yun; Xiao, Minlei; Chen, Lin

    2016-08-01

    In this paper, an adaptive pulse amplitude modulation (APAM) scheme is proposed and experimentally demonstrated in the intensity-modulation and direct-detection (IMDD) optical communications system. In the proposed scheme, the channel is divided into two sub-channels, and different PAM mapping can be chosen for different sub-channel according to the fading conditions. In addition, the 20-km standard single mode fiber (SSMF) transmission of 24 Gbit/s 16/4-APAM signal with the spectral efficiency (SE) up to 6 bit/s/Hz is experimentally demonstrated. The experiment results show that the bit error rate (BER) of the 16/4-APAM signal can be achieved less than 2.4e-2.

  3. General model of signal propagation in a Raman amplified single-mode fiber based coherent optical communication system

    Science.gov (United States)

    Cheng, Jingchi; Tang, Ming; Fu, Songnian; Shum, Perry Ping; Liu, Deming

    2016-12-01

    The distributed Raman amplifier (DRA) has been widely utilized in state-of-the-art coherent optical communication systems using multi-level modulation formatted signals in order to improve transmission performance. A general model based on Jones vector notation governing the signal propagation under Raman amplified link is proposed. Primary physics including both linear and nonlinear effects have been taken into account. The numerical approach for solving the equations is illustrated in detail. Using the model, system characterization and optimization can be easily performed. We also compare our model with the commonly used coarse-step method. It is found that the coarse-step method will exaggerate the cross-polarization modulation induced impairments by over 6 dB and will become unusable when the pump power is as high as several Watts. The proposed model provides a guideline for the simulation of Raman amplified coherent transmission systems.

  4. Comportamento vocal de cantores populares

    OpenAIRE

    Zimmer,Valquíria; Cielo,Carla Aparecida; Ferreira,Fernanda Mariotto

    2012-01-01

    OBJETIVO: investigar aspectos do histórico, hábitos e comportamentos vocais de cantores populares, conforme o sexo e as categorias profissional e amador. MÉTODO: entrevista com 47 cantores, 25 homens e 22 mulheres. RESULTADOS: significância estatística nos seguintes achados: MASCULINO - microfone nos ensaios, ausência de problemas vocais diagnosticados, ausência de orientações sobre higiene vocal, dor ou desconforto após cantar, ausência de alergias e problemas respiratórios; FEMININO - aulas...

  5. Air pollution impedes plant-to-plant communication, but what is the signal?

    Science.gov (United States)

    Blande, James D; Li, Tao; Holopainen, Jarmo K

    2011-07-01

    Since the first reports that undamaged plants gain defensive benefits following exposure to damaged neighbors, the idea that plants may signal to each other has attracted much interest. There has also been substantial debate concerning the ecological significance of the process and the evolutionary drivers. Part of this debate has centered on the distance over which signaling between plants occurs in nature. In a recent study we showed that an ozone concentration of 80 ppb, commonly encountered in nature, significantly reduces the distance over which plant-plant signaling occurs in lima bean. We went on to show that degradation of herbivore-induced plant volatiles by ozone is the likely mechanism for this. The key question remaining from our work was that if ozone is degrading the signal in transit between plants, which chemicals are responsible for transmitting the signal in purer air? Here we present the results of a small scale experiment testing the role of the two most significant herbivore-induced terpenes and discuss our results in terms of other reported functions for these chemicals in plant-plant signaling.

  6. SMART IRRIGATION TECHNIQUE USING VOCAL COMMANDS

    Directory of Open Access Journals (Sweden)

    V.Divya

    2013-02-01

    Full Text Available In this wireless communication era, mobile phones have become a necessity in the common man’s life. Besides being capable of making calls and sending messages, the latest advancements in mobile phones facilitate them to connect to the internet also. With these capabilities, there has been an unprecedented use of mobile phones in many areas of automation. One such area where mobile phone can help with the automation is irrigation process. The main aim of the work is to simplify the method of irrigation using vocal commands through the mobile phone. The Farmer just needs to call a fixed number and utter the control commands through his phone. The control system at the field involves a PIC microcontroller interfaced with GSM modem to receive the command from the farmer and a voice recognition unit which decodes it. The motor is turned on/off according to the decoded commands by the controller. In addition, the system also sends back a message to the farmer’s mobile about the action that has taken place. The power detection and battery backup unit helps in detecting the power availability in the field and inform the farmer about the same, even if the there is no supply at the field. The moisture sensor attached to the system helps in collecting the moisture content of the soil and switch off the motor after it reaches the required value.

  7. Child vocalization composition as discriminant information for automatic autism detection.

    Science.gov (United States)

    Xu, Dongxin; Gilkerson, Jill; Richards, Jeffrey; Yapanel, Umit; Gray, Sharmi

    2009-01-01

    Early identification is crucial for young children with autism to access early intervention. The existing screens require either a parent-report questionnaire and/or direct observation by a trained practitioner. Although an automatic tool would benefit parents, clinicians and children, there is no automatic screening tool in clinical use. This study reports a fully automatic mechanism for autism detection/screening for young children. This is a direct extension of the LENA (Language ENvironment Analysis) system, which utilizes speech signal processing technology to analyze and monitor a child's natural language environment and the vocalizations/speech of the child. It is discovered that child vocalization composition contains rich discriminant information for autism detection. By applying pattern recognition and machine learning approaches to child vocalization composition data, accuracy rates of 85% to 90% in cross-validation tests for autism detection have been achieved at the equal-error-rate (EER) point on a data set with 34 children with autism, 30 language delayed children and 76 typically developing children. Due to its easy and automatic procedure, it is believed that this new tool can serve a significant role in childhood autism screening, especially in regards to population-based or universal screening.

  8. Perceptual cues in nonverbal vocal expressions of emotion.

    Science.gov (United States)

    Sauter, Disa A; Eisner, Frank; Calder, Andrew J; Scott, Sophie K

    2010-11-01

    Work on facial expressions of emotions (Calder, Burton, Miller, Young, & Akamatsu, [2001]) and emotionally inflected speech (Banse & Scherer, [1996]) has successfully delineated some of the physical properties that underlie emotion recognition. To identify the acoustic cues used in the perception of nonverbal emotional expressions like laugher and screams, an investigation was conducted into vocal expressions of emotion, using nonverbal vocal analogues of the "basic" emotions (anger, fear, disgust, sadness, and surprise; Ekman & Friesen, [1971]; Scott et al., [1997]), and of positive affective states (Ekman, [1992], [2003]; Sauter & Scott, [2007]). First, the emotional stimuli were categorized and rated to establish that listeners could identify and rate the sounds reliably and to provide confusion matrices. A principal components analysis of the rating data yielded two underlying dimensions, correlating with the perceived valence and arousal of the sounds. Second, acoustic properties of the amplitude, pitch, and spectral profile of the stimuli were measured. A discriminant analysis procedure established that these acoustic measures provided sufficient discrimination between expressions of emotional categories to permit accurate statistical classification. Multiple linear regressions with participants' subjective ratings of the acoustic stimuli showed that all classes of emotional ratings could be predicted by some combination of acoustic measures and that most emotion ratings were predicted by different constellations of acoustic features. The results demonstrate that, similarly to affective signals in facial expressions and emotionally inflected speech, the perceived emotional character of affective vocalizations can be predicted on the basis of their physical features.

  9. From Signals to Cyber: The Rise, Fall, and Resurrection of the Air Force Communications Officer

    Science.gov (United States)

    2010-06-01

    attached, the Air Force adopted a very different type of organization. Those differences have had a profound effect on the formation of the Air Force’s... impression that the communications community was “taking over” the data automation community.23 After transferring data automation personnel and equipment...27Beth J. Asch and John T. Warner, An Examination of the Effects of Voluntary Separation on Incentives (Santa Monica: Rand, 2001), 5-7

  10. Pharmacology of Ultrasonic Vocalizations in adult Rats: Significance, Call Classification and Neural Substrate.

    Science.gov (United States)

    Brudzynski, Stefan M

    2015-01-01

    Pharmacological studies of emotional arousal and initiation of emotional states in rats measured by their ultrasonic vocalizations are reviewed. It is postulated that emission of vocalizations is an inseparable feature of emotional states and it evolved from mother-infant interaction. Positive emotional states are associated with emission of 50 kHz vocalizations that could be induced by rewarding situations and dopaminergic activation of the nucleus accumbens and are mediated by D1, D2, and partially D3 dopamine receptors. Three biologically significant subtypes of 50 kHz vocalizations have been identified, all expressing positive emotional states: (1) flat calls without frequency modulation that serve as contact calls during social interactions; (2) frequencymodulated calls without trills that signal rewarding and significantly motivated situation; and (3) frequency-modulated calls with trills or trills themselves that are emitted in highly emotional situations associated with intensive affective state. Negative emotional states are associated with emission of 22 kHz vocalizations that could be induced by aversive situations, muscarinic cholinergic activation of limbic areas of medial diencephalon and forebrain, and are mediated by M2 muscarinic receptors. Two biologically significant subtypes of 22 kHz vocalizations have been identified, both expressing negative emotional sates: (1) long calls that serve as alarm calls and signal external danger; and (2) short calls that express a state of discomfort without external danger. The positive and negative states with emission of vocalizations are initiated by two ascending reticular activating subsystems: the mesolimbic dopaminergic subsystem as a specific positive arousal system, and the mesolimbic cholinergic subsystem as a specific negative arousal system.

  11. Learned vocal variation is associated with abrupt cryptic genetic change in a parrot species complex.

    Directory of Open Access Journals (Sweden)

    Raoul F H Ribot

    Full Text Available Contact zones between subspecies or closely related species offer valuable insights into speciation processes. A typical feature of such zones is the presence of clinal variation in multiple traits. The nature of these traits and the concordance among clines are expected to influence whether and how quickly speciation will proceed. Learned signals, such as vocalizations in species having vocal learning (e.g. humans, many birds, bats and cetaceans, can exhibit rapid change and may accelerate reproductive isolation between populations. Therefore, particularly strong concordance among clines in learned signals and population genetic structure may be expected, even among continuous populations in the early stages of speciation. However, empirical evidence for this pattern is often limited because differences in vocalisations between populations are driven by habitat differences or have evolved in allopatry. We tested for this pattern in a unique system where we may be able to separate effects of habitat and evolutionary history. We studied geographic variation in the vocalizations of the crimson rosella (Platycercus elegans parrot species complex. Parrots are well known for their life-long vocal learning and cognitive abilities. We analysed contact calls across a ca 1300 km transect encompassing populations that differed in neutral genetic markers and plumage colour. We found steep clinal changes in two acoustic variables (fundamental frequency and peak frequency position. The positions of the two clines in vocal traits were concordant with a steep cline in microsatellite-based genetic variation, but were discordant with the steep clines in mtDNA, plumage and habitat. Our study provides new evidence that vocal variation, in a species with vocal learning, can coincide with areas of restricted gene flow across geographically continuous populations. Our results suggest that traits that evolve culturally can be strongly associated with reduced gene flow

  12. The Lombard effect in male ultrasonic frogs: Regulating antiphonal signal frequency and amplitude in noise

    Science.gov (United States)

    Shen, Jun-Xian; Xu, Zhi-Min

    2016-01-01

    Acoustic communication in noisy environments presents a significant challenge for vocal animals because noise can interfere with animal acoustic signals by decreasing signal-to-noise ratios and masking signals. Birds and mammals increase call intensity or frequency as noise levels increase, but it is unclear to what extend this behavior is shared by frogs. Concave-eared torrent frogs (Odorrana tormota) have evolved the capacity to produce various calls containing ultrasonic harmonics and to communicate beside noisy streams. However, it is largely unclear how frogs regulate vocalization in response to increasing noise levels. We exposed male frogs to various levels of noise with playback of conspecific female courtship calls and recorded antiphonal signals and spontaneous short calls. Males were capable of rapidly adjusting fundamental frequency and amplitude of antiphonal signals as noise levels increased. The increment in fundamental frequency and amplitude was approximately 0.5 kHz and 3 dB with every 10 dB increase in noise level, indicating the presence of noise-dependent signal characteristics. Males showed the noise-tolerant adaption in response to female calls in noise level from 40 to 90 dB SPL. The results suggest that the noise-dependent signal characteristics in O. tormota have evolved as a strategy to cope with varying torrent noise. PMID:27345957

  13. Signal-to-noise ratio estimation in digital computer simulation of lowpass and bandpass systems with applications to analog and digital communications, volume 3

    Science.gov (United States)

    Tranter, W. H.; Turner, M. D.

    1977-01-01

    Techniques are developed to estimate power gain, delay, signal-to-noise ratio, and mean square error in digital computer simulations of lowpass and bandpass systems. The techniques are applied to analog and digital communications. The signal-to-noise ratio estimates are shown to be maximum likelihood estimates in additive white Gaussian noise. The methods are seen to be especially useful for digital communication systems where the mapping from the signal-to-noise ratio to the error probability can be obtained. Simulation results show the techniques developed to be accurate and quite versatile in evaluating the performance of many systems through digital computer simulation.

  14. The Risk of Vocal Fold Atrophy after Serial Corticosteroid Injections of the Vocal Fold.

    Science.gov (United States)

    Shi, Lucy L; Giraldez-Rodriguez, Laureano A; Johns, Michael M

    2016-11-01

    The aim of this study was to illustrate the risk of vocal fold atrophy in patients who receive serial subepithelial steroid injections for vocal fold scar. This study is a retrospective case report of two patients who underwent a series of weekly subepithelial infusions of 10 mg/mL dexamethasone for benign vocal fold lesion. Shortly after the procedures, both patients developed a weak and breathy voice. The first patient was a 53-year-old man with radiation-induced vocal fold stiffness. Six injections were performed unilaterally, and 1 week later, he developed unilateral vocal fold atrophy with new glottal insufficiency. The second patient was a 67-year-old woman with severe vocal fold inflammation related to laryngitis and calcinosis, Raynaud's phenomenon, esophagean dysmotility, sclerodactyly, and telangiectasia (CREST) syndrome. Five injections were performed bilaterally, and 1 week later, she developed bilateral vocal fold atrophy with a large midline glottal gap during phonation. In both cases, the steroid-induced vocal atrophy resolved spontaneously after 4 months. Serial subepithelial steroid infusions of the vocal folds, although safe in the majority of patients, carry the risk of causing temporary vocal fold atrophy when given at short intervals. Copyright © 2016 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  15. Signal processing approaches to secure physical layer communications in multi-antenna wireless systems

    CERN Document Server

    Hong, Y-W Peter; Kuo, C-C Jay

    2013-01-01

    This book introduces various signal processing approaches to enhance physical layer secrecy in multi-antenna wireless systems. Wireless physical layer secrecy has attracted much attention in recent years due to the broadcast nature of the wireless medium and its inherent vulnerability to eavesdropping. While most articles on physical layer secrecy focus on the information-theoretic aspect, we focus specifically on the signal processing aspects, including beamforming and precoding techniques for data transmission and discriminatory training schemes for channel estimation. The discussions will c

  16. Exposure to advertisement calls of reproductive competitors activates vocal-acoustic and catecholaminergic neurons in the plainfin midshipman fish, Porichthys notatus.

    Science.gov (United States)

    Petersen, Christopher L; Timothy, Miky; Kim, D Spencer; Bhandiwad, Ashwin A; Mohr, Robert A; Sisneros, Joseph A; Forlano, Paul M

    2013-01-01

    While the neural circuitry and physiology of the auditory system is well studied among vertebrates, far less is known about how the auditory system interacts with other neural substrates to mediate behavioral responses to social acoustic signals. One species that has been the subject of intensive neuroethological investigation with regard to the production and perception of social acoustic signals is the plainfin midshipman fish, Porichthys notatus, in part because acoustic communication is essential to their reproductive behavior. Nesting male midshipman vocally court females by producing a long duration advertisement call. Females localize males by their advertisement call, spawn and deposit all their eggs in their mate's nest. As multiple courting males establish nests in close proximity to one another, the perception of another male's call may modulate individual calling behavior in competition for females. We tested the hypothesis that nesting males exposed to advertisement calls of other males would show elevated neural activity in auditory and vocal-acoustic brain centers as well as differential activation of catecholaminergic neurons compared to males exposed only to ambient noise. Experimental brains were then double labeled by immunofluorescence (-ir) for tyrosine hydroxylase (TH), an enzyme necessary for catecholamine synthesis, and cFos, an immediate-early gene product used as a marker for neural activation. Males exposed to other advertisement calls showed a significantly greater percentage of TH-ir cells colocalized with cFos-ir in the noradrenergic locus coeruleus and the dopaminergic periventricular posterior tuberculum, as well as increased numbers of cFos-ir neurons in several levels of the auditory and vocal-acoustic pathway. Increased activation of catecholaminergic neurons may serve to coordinate appropriate behavioral responses to male competitors. Additionally, these results implicate a role for specific catecholaminergic neuronal groups in

  17. Exposure to advertisement calls of reproductive competitors activates vocal-acoustic and catecholaminergic neurons in the plainfin midshipman fish, Porichthys notatus.

    Directory of Open Access Journals (Sweden)

    Christopher L Petersen

    Full Text Available While the neural circuitry and physiology of the auditory system is well studied among vertebrates, far less is known about how the auditory system interacts with other neural substrates to mediate behavioral responses to social acoustic signals. One species that has been the subject of intensive neuroethological investigation with regard to the production and perception of social acoustic signals is the plainfin midshipman fish, Porichthys notatus, in part because acoustic communication is essential to their reproductive behavior. Nesting male midshipman vocally court females by producing a long duration advertisement call. Females localize males by their advertisement call, spawn and deposit all their eggs in their mate's nest. As multiple courting males establish nests in close proximity to one another, the perception of another male's call may modulate individual calling behavior in competition for females. We tested the hypothesis that nesting males exposed to advertisement calls of other males would show elevated neural activity in auditory and vocal-acoustic brain centers as well as differential activation of catecholaminergic neurons compared to males exposed only to ambient noise. Experimental brains were then double labeled by immunofluorescence (-ir for tyrosine hydroxylase (TH, an enzyme necessary for catecholamine synthesis, and cFos, an immediate-early gene product used as a marker for neural activation. Males exposed to other advertisement calls showed a significantly greater percentage of TH-ir cells colocalized with cFos-ir in the noradrenergic locus coeruleus and the dopaminergic periventricular posterior tuberculum, as well as increased numbers of cFos-ir neurons in several levels of the auditory and vocal-acoustic pathway. Increased activation of catecholaminergic neurons may serve to coordinate appropriate behavioral responses to male competitors. Additionally, these results implicate a role for specific catecholaminergic

  18. Background noise cancellation for improved acoustic detection of manatee vocalizations

    Science.gov (United States)

    Yan, Zheng; Niezrecki, Christopher; Beusse, Diedrich O.

    2005-06-01

    The West Indian manatee (Trichechus manatus latirostris) has become endangered partly because of an increase in the number of collisions with boats. A device to alert boaters of the presence of manatees, so that a collision can be avoided, is desired. A practical implementation of the technology is dependent on the hydrophone spacing and range of detection. These parameters are primarily dependent on the manatee vocalization strength, the decay of the signal's strength with distance, and the background noise levels. An efficient method to extend the detection range by using background noise cancellation is proposed in this paper. An adaptive line enhancer (ALE) that can detect and track narrow band signals buried in broadband noise is implemented to cancel the background noise. The results indicate that the ALE algorithm can efficiently extract the manatee calls from the background noise. The improved signal-to-noise ratio of the signal can be used to extend the range of detection of manatee vocalizations and reduce the false alarm and missing detection rate in their natural habitat. .

  19. A Rat Excised Larynx Model of Vocal Fold Scar

    Science.gov (United States)

    Welham, Nathan V.; Montequin, Douglas W.; Tateya, Ichiro; Tateya, Tomoko; Choi, Seong Hee; Bless, Diane M.

    2009-01-01

    Purpose: To develop and evaluate a rat excised larynx model for the measurement of acoustic, aerodynamic, and vocal fold vibratory changes resulting from vocal fold scar. Method: Twenty-four 4-month-old male Sprague-Dawley rats were assigned to 1 of 4 experimental groups: chronic vocal fold scar, chronic vocal fold scar treated with 100-ng basic…

  20. The Transition from Animal to Linguistic Communication.

    Science.gov (United States)

    Smit, Harry

    Darwin's theory predicts that linguistic behavior gradually evolved out of animal forms of communication (signaling). However, this prediction is confronted by the conceptual problem that there is an essential difference between signaling and linguistic behavior: using words is a normative practice. It is argued that we can resolve this problem if we (1) note that language evolution is the outcome of an evolutionary transition, and (2) observe that the use of words evolves during ontogenesis out of babbling. It is discussed that language evolved as the result of an expansion of the vocalizing powers of our ancestors. This involved an increase in the volitional control of our speech apparatus (leading to the ability to produce new combinations of vowels and consonants), but also the evolution of socially guided learning. It resulted in unique human abilities, namely doing things with words and later reasoning and giving reasons.

  1. Real estate ads in Emei music frog vocalizations: female preference for calls emanating from burrows.

    Science.gov (United States)

    Cui, Jianguo; Tang, Yezhong; Narins, Peter M

    2012-06-23

    During female mate choice, both the male's phenotype and resources (e.g. his nest) contribute to the chooser's fitness. Animals other than humans are not known to advertise resource characteristics to potential mates through vocal communication; although in some species of anurans and birds, females do evaluate male qualities through vocal communication. Here, we demonstrate that calls of the male Emei music frog (Babina dauchina), vocalizing from male-built nests, reflect nest structure information that can be recognized by females. Inside-nest calls consisted of notes with energy concentrated at lower frequency ranges and longer note durations when compared with outside-nest calls. Centre frequencies and note durations of the inside calls positively correlate with the area of the burrow entrance and the depth of the burrow, respectively. When given a choice between outside and inside calls played back alternately, more than 70 per cent of the females (33/47) chose inside calls. These results demonstrate that males of this species faithfully advertise whether or not they possess a nest to potential mates by vocal communication, which probably facilitates optimal mate selection by females. These results revealed a novel function of advertisement calls, which is consistent with the wide variation in both call complexity and social behaviour within amphibians.

  2. Communications article

    KAUST Repository

    Fariborzi, Hossein

    2017-07-20

    Seamless, covert communications using a communications system integrated or incorporated within an article of clothing is described. In one embodiment, the communications system is integrated or incorporated into a shoe insole and includes a haptic feedback mechanism, a communications module, a flexible pressure sensor, and a battery. The communications module includes a wireless communications module for wireless communications, a wired interface for wired communications, a microcontroller, and a battery charge controller. The flexible pressure sensor can be actuated by an individual\\'s toe, for example, and communication between two communications nodes can be achieved using coded signals sent by individuals using a combination of long and short presses on the pressure sensor. In response to the presses, wireless communications modules can transmit and receive coded signals based on the presses.

  3. The Effects of Hearing Protectors on Speech Communication and the Perception of Warning Signals

    Science.gov (United States)

    1989-06-01

    sensorineural hearing loss (S) . While the...Figure 1. Effect of earmuffs on the audibility of a signal in noise by a subject with normal hearing (N) and one with sensorineural hearing loss (S). Upper...investigated the psychological and social effects of " sudden hearing loss " by occluding the ears of normal- hearing individuals. Subjects wore earplugs

  4. Reinforcement Delay Fading during Differential Reinforcement of Communication: The Effects of Signals on Response Maintenance

    Science.gov (United States)

    Kelley, Michael E.; Lerman, Dorothea C.; Fisher, Wayne W.; Roane, Henry S.; Zangrillo, Amanda N.

    2011-01-01

    Signals during delays to reinforcement may lessen reductions in responding that typically occur when there is a delay between a response and its reinforcer. Sparse applied research has been devoted to understanding the conditions under which responding may be maintained when delays to reinforcement are introduced. We evaluated the extent to which…

  5. MIMO系统的信号检测算法%Research on Signal Detection Algorithms For MIMO Communication Systems

    Institute of Scientific and Technical Information of China (English)

    田根林; 李华

    2016-01-01

    In the high-speed broadband wireless communication systems, Multi-input and multi-output(MIMO) technology can improve transmission rate and spectrum efficiencies without any increase of system bandwidth and transmitting power. Thus, the signal detection for MIMO systems is challenging because of the channel noise and multipath fading, and has become the biggest block of development. In this paper, most attention is concentrated on the signal detection algorithms for MIMO Communication Systems, through the comparision with the existent algorithms and the simulations, we can conclude that the signal detection algorithm based on sphere decoding has a better detection effect. Due to the introduction of the interference cancellation and the ordering rule, the algorithm optimality of ZF-OSIC and MMSE-OSIC is both improved effectively.%在高速宽带无线通信系统中,MIMO技术能够在不增加系统带宽和发射功率的情况下,有效提高系统传输速率和频谱效率。然而,由于不同发射天线发出的信号的相互干扰以及无线通信系统的多径效应,使得MIMO系统的信号检测面临巨大挑战,严重阻碍了MIMO技术的广泛应用。因此本文主要针对MIMO系统的信号检测算法进行研究,通过算法比较和仿真验证可以得出,基于球形译码的信号检测(SD)算法具有更优的检测结果。由于引入干扰抵消和排序机制,ZF-OSIC和MMSE-OSIC算法在性能方面得到了提升。

  6. Network coding based joint signaling and dynamic bandwidth allocation scheme for inter optical network unit communication in passive optical networks

    Science.gov (United States)

    Wei, Pei; Gu, Rentao; Ji, Yuefeng

    2014-06-01

    As an innovative and promising technology, network coding has been introduced to passive optical networks (PON) in recent years to support inter optical network unit (ONU) communication, yet the signaling process and dynamic bandwidth allocation (DBA) in PON with network coding (NC-PON) still need further study. Thus, we propose a joint signaling and DBA scheme for efficiently supporting differentiated services of inter ONU communication in NC-PON. In the proposed joint scheme, the signaling process lays the foundation to fulfill network coding in PON, and it can not only avoid the potential threat to downstream security in previous schemes but also be suitable for the proposed hybrid dynamic bandwidth allocation (HDBA) scheme. In HDBA, a DBA cycle is divided into two sub-cycles for applying different coding, scheduling and bandwidth allocation strategies to differentiated classes of services. Besides, as network traffic load varies, the entire upstream transmission window for all REPORT messages slides accordingly, leaving the transmission time of one or two sub-cycles to overlap with the bandwidth allocation calculation time at the optical line terminal (the OLT), so that the upstream idle time can be efficiently eliminated. Performance evaluation results validate that compared with the existing two DBA algorithms deployed in NC-PON, HDBA demonstrates the best quality of service (QoS) support in terms of delay for all classes of services, especially guarantees the end-to-end delay bound of high class services. Specifically, HDBA can eliminate queuing delay and scheduling delay of high class services, reduce those of lower class services by at least 20%, and reduce the average end-to-end delay of all services over 50%. Moreover, HDBA also achieves the maximum delay fairness between coded and uncoded lower class services, and medium delay fairness for high class services.

  7. Vocal Loading in Speaking a Foreign Language.

    Science.gov (United States)

    Järvinen, Kati; Laukkanen, Anne-Maria

    2015-01-01

    This study investigated whether speaking a foreign language affects the subjective notions of vocal fatigue, and whether acoustic measurements reveal a higher vocal loading. The speech samples of 20 native Finnish-speaking and 23 native English-speaking subjects were recorded in Finnish and in English. From the speech samples, fundamental frequency, equivalent sound level, total duration of voiced speech, speech rate, alpha ratio and L1-L0 level difference were analyzed. Vocal doses were calculated. According to subjective notions, the voice gets tired more quickly when speaking a foreign language. The mean fundamental frequency increased but the speech rate and total duration of voiced speech decreased significantly when speaking a foreign language. Thus, the vocal doses decreased. The subjective sensations of increased vocal fatigue may be due to increased mental stress rather than to higher vocal loading. However, a trend that speaking a foreign language may involve more loading was found in L1-L0 level difference and in the doses normalized to time dose. Longer speech samples should be studied. Voice quality-based indicators of vocal loading are worth testing in addition to the measures based on the amount of voicing in speech. © 2015 S. Karger AG, Basel.

  8. TESTING NEW TYPES OF ROLLING STOCK FOR ELECTROMAGNETIC COMPATIBILITY WITH SIGNALING AND COMMUNICATION DEVICES

    Directory of Open Access Journals (Sweden)

    V. I. Havrilyuk

    2015-09-01

    Full Text Available Purpose. In the paper there is the comparative analysis of standards and methods of measurements of electromagnetic interference, those are caused by electrical equipment of new types of rolling stock with AC and DC-current electric traction in accordance with the normative documents are adopted in Ukraine and the EU. The development on this basis the measuring method of current interference in traction network, generated by the electrical equipment of electric rolling stock (ERS applicable to testing the new types of rolling stock for electromagnetic compatibility (EMC with different systems of railway signaling is also needed. Methodology. The testing method has been offered. It includes measurements in power circuits of rolling stock, as well as in track devices of signalization systems. Findings. Norms and methods tests of a rolling stock on electromagnetic compatibility with track circuits (TC were analyzed. It was found that a large variety of electricity supply systems, signalization and link in Europe makes it necessary to test new types of electric rolling stock for electromagnetic compatibility with pick up unit in each country separately, taking into account the features used in its systems. It is greatly increases the cost of introducing new types of rolling stock. The test method of electric rolling stock EMC with track circuits has been developed; it includes measurement in power circuits of rolling stock, as well as in track devices of signalization systems. Measurements in accordance with the proposed methodology for electric rolling stock with asynchronous traction drive when driving on sections electrified at AC and DC have been carried out. The values of the interference current in track circuit to all the frequencies of the signal current have been defined. It is shown that under some modes of the train the interference current exceed the permissible values. Originality. The method for measuring interference current generated

  9. Vocal learning beyond imitation: mechanisms of adaptive vocal development in songbirds and human infants.

    Science.gov (United States)

    Tchernichovski, Ofer; Marcus, Gary

    2014-10-01

    Studies of vocal learning in songbirds typically focus on the acquisition of sensory templates for song imitation and on the consequent process of matching song production to templates. However, functional vocal development also requires the capacity to adaptively diverge from sensory templates, and to flexibly assemble vocal units. Examples of adaptive divergence include the corrective imitation of abnormal songs, and the decreased tendency to copy over-abundant syllables. Such frequency-dependent effects might mirror tradeoffs between the assimilation of group identity (culture) while establishing individual and flexibly expressive songs. Intriguingly, although the requirements for vocal plasticity vary across songbirds, and more so between birdsong and language, the capacity to flexibly assemble vocal sounds develops in a similar, stepwise manner across species. Therefore, universal features of vocal learning go well beyond the capacity to imitate. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Crossmodal integration of conspecific vocalizations in rhesus macaques.

    Directory of Open Access Journals (Sweden)

    Christa Payne

    Full Text Available Crossmodal integration of audio/visual information is vital for recognition, interpretation and appropriate reaction to social signals. Here we examined how rhesus macaques process bimodal species-specific vocalizations by eye tracking, using an unconstrained preferential looking paradigm. Six adult rhesus monkeys (3M, 3F were presented two side-by-side videos of unknown male conspecifics emitting different vocalizations, accompanied by the audio signal corresponding to one of the videos. The percentage of time animals looked to each video was used to assess crossmodal integration ability and the percentages of time spent looking at each of the six a priori ROIs (eyes, mouth, and rest of each video were used to characterize scanning patterns. Animals looked more to the congruent video, confirming reports that rhesus monkeys spontaneously integrate conspecific vocalizations. Scanning patterns showed that monkeys preferentially attended to the eyes and mouth of the stimuli, with subtle differences between males and females such that females showed a tendency to differentiate the eye and mouth regions more than males. These results were similar to studies in humans indicating that when asked to assess emotion-related aspects of visual speech, people preferentially attend to the eyes. Thus, the tendency for female monkeys to show a greater differentiation between the eye and mouth regions than males may indicate that female monkeys were slightly more sensitive to the socio-emotional content of complex signals than male monkeys. The current results emphasize the importance of considering both the sex of the observer and individual variability in passive viewing behavior in nonhuman primate research.

  11. Turning signals into meaning--'shared decision making' meets communication theory.

    Science.gov (United States)

    Kasper, Jürgen; Légaré, France; Scheibler, Fülöp; Geiger, Friedemann

    2012-03-01

    Shared decision making (SDM) is being increasingly challenged for promoting an innovative role model while adhering to an archaic approach to patient-clinician communication, both in clinical practice and the research field. Too often, SDM has been studied at the individual level, which ignores the interpersonal system between patients and physicians. We aimed to encourage debate by reflecting on the essentials of SDM in terms of epistemology. We operationalized the SDM core concept of information exchange in terms of social systems theory. An epistemological analysis of the term information refers to its inherent process character. Exchange of information thereby becomes synonymous with social sense construction, indicating that, rather than just being a vehicle, the act of communication itself is the information. We plead for the adoption of existing dyadic analytical methods such as those offered by the interpersonal paradigm. Implications of an updated concept of information for the use of SDM-evaluation methods, for SDM-goal setting, and for clinical practice of SDM are described. © 2011 Blackwell Publishing Ltd.

  12. Sodium channel genes and the evolution of diversity in communication signals of electric fishes: convergent molecular evolution.

    Science.gov (United States)

    Zakon, Harold H; Lu, Ying; Zwickl, Derrick J; Hillis, David M

    2006-03-07

    We investigated whether the evolution of electric organs and electric signal diversity in two independently evolved lineages of electric fishes was accompanied by convergent changes on the molecular level. We found that a sodium channel gene (Na(v)1.4a) that is expressed in muscle in nonelectric fishes has lost its expression in muscle and is expressed instead in the evolutionarily novel electric organ in both lineages of electric fishes. This gene appears to be evolving under positive selection in both lineages, facilitated by its restricted expression in the electric organ. This view is reinforced by the lack of evidence for selection on this gene in one electric species in which expression of this gene is retained in muscle. Amino acid replacements occur convergently in domains that influence channel inactivation, a key trait for shaping electric communication signals. Some amino acid replacements occur at or adjacent to sites at which disease-causing mutations have been mapped in human sodium channel genes, emphasizing that these replacements occur in functionally important domains. Selection appears to have acted on the final step in channel inactivation, but complementarily on the inactivation "ball" in one lineage, and its receptor site in the other lineage. Thus, changes in the expression and sequence of the same gene are associated with the independent evolution of signal complexity.

  13. Exposure Setup and Dosimetry for a Study on Effects of Mobile Communication Signals on Human Hematopoietic Stem Cells in vitro

    Science.gov (United States)

    Rohland, Martina; Baaske, Kai; Gläser, Katharina; Hintzsche, Henning; Stopper, Helga; Kleine-Ostmann, Thomas; Schrader, Thorsten

    2017-09-01

    In this paper we describe the design of an exposure setup used to study possible non-thermal effects due to the exposure of human hematopoietic stem cells to GSM, UMTS and LTE mobile communication signals. The experiments are performed under fully blinded conditions in a TEM waveguide located inside an incubator to achieve defined environmental conditions as required for the living cells. Chamber slides containing the cells in culture medium are placed on the septum of the waveguide. The environmental and exposure parameters such as signal power, temperatures, relative humidity and CO2 content of the surrounding atmosphere are monitored permanently during the exposure experiment. The power of the exposure signals required to achieve specific absorption rates of 0.5, 1, 2 and 4 W kg-1 are determined by numerical calculation of the field distribution inside the cell culture medium at 900 MHz (GSM), 1950 MHz (UMTS) and 2535 MHz (LTE). The dosimetry is verified both with scattering parameter measurements on the waveguide with and without containers filled with cell culture medium and with temperature measurements with non-metallic probes in separate heating experiments.

  14. Exposure Setup and Dosimetry for a Study on Effects of Mobile Communication Signals on Human Hematopoietic Stem Cells in vitro

    Directory of Open Access Journals (Sweden)

    M. Rohland

    2017-09-01

    Full Text Available In this paper we describe the design of an exposure setup used to study possible non-thermal effects due to the exposure of human hematopoietic stem cells to GSM, UMTS and LTE mobile communication signals. The experiments are performed under fully blinded conditions in a TEM waveguide located inside an incubator to achieve defined environmental conditions as required for the living cells. Chamber slides containing the cells in culture medium are placed on the septum of the waveguide. The environmental and exposure parameters such as signal power, temperatures, relative humidity and CO2 content of the surrounding atmosphere are monitored permanently during the exposure experiment. The power of the exposure signals required to achieve specific absorption rates of 0.5, 1, 2 and 4 W kg−1 are determined by numerical calculation of the field distribution inside the cell culture medium at 900 MHz (GSM, 1950 MHz (UMTS and 2535 MHz (LTE. The dosimetry is verified both with scattering parameter measurements on the waveguide with and without containers filled with cell culture medium and with temperature measurements with non-metallic probes in separate heating experiments.

  15. Explosive vocal activity for attracting human attention is related to domestication in silver fox.

    Science.gov (United States)

    Gogoleva, Svetlana S; Volodin, Ilya A; Volodina, Elena V; Kharlamova, Anastasia V; Trut, Lyudmila N

    2011-02-01

    Domestication affects behavioral and vocal responses, involved in communication with humans; in particular, those that attract human attention. In this study, we found that silver foxes of Tame strain, experimentally domesticated for a few tenses of generation, displayed bursts of vocal activity during the first minute after appearance of an unfamiliar human, that faded quickly during the remaining time of the test, when the experimenter stayed passively before the cage. Distinctively, foxes of Aggressive strain, artificially selected for tenses of generation for aggressive behavior toward humans, and the control group of Unselected for behavior silver foxes kept steady levels of vocal activity for the duration of the tests. We found also that Aggressive foxes vocalized for a larger proportion of time than Unselected foxes for all 5 min of the test. We discuss the obtained data in relation to proposal effects of domestication on mechanisms directed to involving people into human-animal interactions and structural similarity between human laughter and vocalization of Tame foxes.

  16. Vocal turn-taking in a non-human primate is learned during ontogeny.

    Science.gov (United States)

    Chow, Cecilia P; Mitchell, Jude F; Miller, Cory T

    2015-05-22

    Conversational turn-taking is an integral part of language development, as it reflects a confluence of social factors that mitigate communication. Humans coordinate the timing of speech based on the behaviour of another speaker, a behaviour that is learned during infancy. While adults in several primate species engage in vocal turn-taking, the degree to which similar learning processes underlie its development in these non-human species or are unique to language is not clear. We recorded the natural vocal interactions of common marmosets (Callithrix jacchus) occurring with both their sibling twins and parents over the first year of life and observed at least two parallels with language development. First, marmoset turn-taking is a learned vocal behaviour. Second, marmoset parents potentially played a direct role in guiding the development of turn-taking by providing feedback to their offspring when errors occurred during vocal interactions similarly to what has been observed in humans. Though species-differences are also evident, these findings suggest that similar learning mechanisms may be implemented in the ontogeny of vocal turn-taking across our Order, a finding that has important implications for our understanding of language evolution. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  17. Songbirds tune their vocal tract to the fundamental frequency of their song

    Science.gov (United States)

    Riede, Tobias; Suthers, Roderick A.; Fletcher, Neville H.; Blevins, William E.

    2006-01-01

    In human speech, the sound generated by the larynx is modified by articulatory movements of the upper vocal tract, which acts as a variable resonant filter concentrating energy near particular frequencies, or formants, essential in speech recognition. Despite its potential importance in vocal communication, little is known about the presence of tunable vocal tract filters in other vertebrates. The tonal quality of much birdsong, in which upper harmonics have relatively little energy, depends on filtering of the vocal source, but the nature of this filter is controversial. Current hypotheses treat the songbird vocal tract as a rigid tube with a resonance that is modulated by the end-correction of a variable beak opening. Through x-ray cinematography of singing birds, we show that birdsong is accompanied by cyclical movements of the hyoid skeleton and changes in the diameter of the cranial end of the esophagus that maintain an inverse relationship between the volume of the oropharyngeal cavity and esophagus and the song’s fundamental frequency. A computational acoustic model indicates that this song-related motor pattern tunes the major resonance of the oropharyngeal–esophageal cavity to actively track the song’s fundamental frequency. PMID:16567614

  18. On the importance of being vocal: saying "ow" improves pain tolerance.

    Science.gov (United States)

    Swee, Genevieve; Schirmer, Annett

    2015-04-01

    Vocalizing is a ubiquitous pain behavior. The present study investigated whether it helps alleviate pain and sought to discern potential underlying mechanisms. Participants were asked to immerse one hand in painfully cold water. On separate trials, they said "ow," heard a recording of them saying "ow," heard a recording of another person saying "ow," pressed a button, or sat passively. Compared to sitting passively, saying "ow" increased the duration of hand immersion. Although on average, participants predicted this effect, their expectations were uncorrelated with pain tolerance. Like vocalizing, button pressing increased the duration of hand immersion, and this increase was positively correlated with the vocalizing effect. Hearing one's own or another person's "ow" was not analgesic. Together, these results provide first evidence that vocalizing helps individuals cope with pain. Moreover, they suggest that motor more than other processes contribute to this effect. Participants immersed their hand in painfully cold water longer when saying "ow" than when doing nothing. Whereas button pressing had a similar effect, hearing one's own or another person's "ow" did not. Thus, vocalizing in pain is not only communicative. Like other behaviors, it helps cope with pain. Copyright © 2015 American Pain Society. Published by Elsevier Inc. All rights reserved.

  19. Vocal cord paralysis caused by stingray.

    Science.gov (United States)

    Kwon, Oh Jin; Park, Jung Je; Kim, Jin Pyeong; Woo, Seung Hoon

    2013-11-01

    Foreign bodies in the oral cavity and pharynx are commonly encountered in the emergency room and outpatient departments, and the most frequently observed of these foreign bodies are fish bones. Among the possible complications resulting from a pharyngeal foreign body, vocal cord fixation is extremely rare, with only three cases previously reported in the English literature. The mechanisms of vocal cord fixation can be classified into mechanical articular fixation, direct injury of the recurrent laryngeal nerve, or recurrent laryngeal nerve paralysis secondary to inflammation. The case discussed here is different from previous cases. We report a rare case of vocal cord paralysis caused by the venom of a stingray tail in the hypopharynx.

  20. Vocal cord paralysis in a fighter pilot.

    Science.gov (United States)

    Maturo, Stephen; Brennan, Joseph

    2006-01-01

    We present in this case report the return to flying duty of a pilot with vocal cord paralysis secondary to removal of a thymoma. We discuss the importance of glottic function as it pertains to the unique aviation environment. We also discuss the anatomy and physiology of the glottis, the evaluation for vocal cord paralysis, and surgical approaches for paralyzed vocal cords. Although the incidence of recurrent laryngeal nerve paralysis is low in the military aviation community, it is important to recognize that its sequelae can be managed so that the aviator may return to flight duties.

  1. Communication networks and spatial ecology in nightingales

    NARCIS (Netherlands)

    Naguib, M.; Kunc, H.P.; Sprau, P.; Roth, T.; Amrhein, V.

    2011-01-01

    In most animals, communication plays a central role in a variety of contexts. In this chapter, we synthesize studies on vocal communication and spatial behavior in nightingales, Luscinia megarhynchos, with other research on songbirds to emphasize the need to integrate studies on communication with

  2. Influence of Familiarity on Identifying Prosodic Vocalizations Produced by Children with Severe Dysarthria

    Science.gov (United States)

    Patel, Rupal; Schroeder, Bethany

    2007-01-01

    Familiarity is thought to aid listeners in decoding disordered speech; however, as the speech signal degrades, the "familiarity advantage" becomes less beneficial. Despite highly unintelligible speech sound production, many children with dysarthria vocalize when interacting with familiar caregivers. Perhaps listeners can understand these…

  3. Communicating the Signal of Climate Change in The Presence of Non-Random Noise

    Science.gov (United States)

    Mann, M. E.

    2015-12-01

    The late Stephen Schneider spoke eloquently of the double ethical bind that we face: we must strive to communicate effectively but honestly. This is no simple task given the considerable "noise" generated in our public discourse by vested interests instead working to misinform the public. To do so, we must convey what is known in plainspoken jargon-free language, while acknowledging the real uncertainties that exist. Further, we must explain the implications of those uncertainties, which in many cases imply the possibility of greater, not lesser, risk. Finally, we must not be averse to discussing the policy implications of the science, lest we fail to provide our audience with critical information that can help them make informed choices about their own actions as citizens. I will use examples from my current collaboration with Washington Post editorial cartoonist Tom Toles.

  4. Biomedical signal acquisition with streaming wireless communication for recording evoked potentials.

    Science.gov (United States)

    Thie, Johnson; Klistorner, Alexander; Graham, Stuart L

    2012-10-01

    Commercial electrophysiology systems for recording evoked potentials always connect patients to the acquisition unit via long wires. Wires guarantee timely transfer of signals for synchronization with the stimuli, but they are susceptible to electromagnetic and electrostatic interferences. Though wireless solutions are readily available (e.g. Bluetooth), they introduce high delay variability that will distort the evoked potential traces. We developed a complete wireless acquisition system with a fixed delay. The system supports up to 4 bipolar channels; each is amplified by 20,000× and digitized to 24 bits. The system incorporates the "driven-right-leg" circuit to lower the common noise. Data are continuously streamed using radio-frequency transmission operating at 915 MHz and then tagged with the stimulus SYNC signal at the receiver. The delay, noise level and transmission error rate were measured. Flash visual evoked potentials were recorded monocularly from both eyes of six adults with normal vision. The signals were acquired via wireless and wired transmissions simultaneously. The recording was repeated on some participants within 2 weeks. The delay was constant at 20 ms. The system noise was white and Gaussian (2 microvolts RMS). The transmission error rate was about one per million packets. The VEPs recorded with wireless transmission were consistent with those with wired transmission. The VEP amplitudes and shapes showed good intra-session and inter-session reproducibility and were consistent across eyes. The wireless acquisition system can reliably record visual evoked potentials. It has a constant delay of 20 ms and very low error rate.

  5. Optimal space communications techniques. [using digital and phase locked systems for signal processing

    Science.gov (United States)

    Schilling, D. L.

    1974-01-01

    Digital multiplication of two waveforms using delta modulation (DM) is discussed. It is shown that while conventional multiplication of two N bit words requires N2 complexity, multiplication using DM requires complexity which increases linearly with N. Bounds on the signal-to-quantization noise ratio (SNR) resulting from this multiplication are determined and compared with the SNR obtained using standard multiplication techniques. The phase locked loop (PLL) system, consisting of a phase detector, voltage controlled oscillator, and a linear loop filter, is discussed in terms of its design and system advantages. Areas requiring further research are identified.

  6. A Novel Efficient Cluster-Based MLSE Equalizer for Satellite Communication Channels with -QAM Signaling

    Directory of Open Access Journals (Sweden)

    Dalakas Vassilis

    2006-01-01

    Full Text Available In satellites, nonlinear amplifiers used near saturation severely distort the transmitted signal and cause difficulties in its reception. Nevertheless, the nonlinearities introduced by memoryless bandpass amplifiers preserve the symmetries of the -ary quadrature amplitude modulation ( -QAM constellation. In this paper, a cluster-based sequence equalizer (CBSE that takes advantage of these symmetries is presented. The proposed equalizer exhibits enhanced performance compared to other techniques, including the conventional linear transversal equalizer, Volterra equalizers, and RBF network equalizers. Moreover, this gain in performance is obtained at a substantially lower computational cost.

  7. Critical role of gap junction communication, calcium and nitric oxide signaling in bystander responses to focal photodynamic injury.

    Science.gov (United States)

    Calì, Bianca; Ceolin, Stefano; Ceriani, Federico; Bortolozzi, Mario; Agnellini, Andrielly H R; Zorzi, Veronica; Predonzani, Andrea; Bronte, Vincenzo; Molon, Barbara; Mammano, Fabio

    2015-04-30

    Ionizing and nonionizing radiation affect not only directly targeted cells but also surrounding "bystander" cells. The underlying mechanisms and therapeutic role of bystander responses remain incompletely defined. Here we show that photosentizer activation in a single cell triggers apoptosis in bystander cancer cells, which are electrically coupled by gap junction channels and support the propagation of a Ca2+ wave initiated in the irradiated cell. The latter also acts as source of nitric oxide (NO) that diffuses to bystander cells, in which NO levels are further increased by a mechanism compatible with Ca(2+)-dependent enzymatic production. We detected similar signals in tumors grown in dorsal skinfold chambers applied to live mice. Pharmacological blockade of connexin channels significantly reduced the extent of apoptosis in bystander cells, consistent with a critical role played by intercellular communication, Ca2+ and NO in the bystander effects triggered by photodynamic therapy.

  8. Human cerebral response to animal affective vocalizations

    National Research Council Canada - National Science Library

    Pascal Belin; Shirley Fecteau; Ian Charest; Nicholas Nicastro; Marc D Hauser; Jorge L Armony

    2008-01-01

    .... Here, we used functional magnetic resonance imaging in normal participants to measure cerebral activity during auditory stimulation with affectively valenced animal vocalizations, some familiar (cats) and others not (rhesus monkeys...

  9. Design and Implementation of an Efficient Software Communications Architecture Core Framework for a Digital Signal Processors Platform

    Directory of Open Access Journals (Sweden)

    Wael A. Murtada

    2011-01-01

    Full Text Available Problem statement: The Software Communications Architecture (SCA was developed to improve software reuse and interoperability in Software Defined Radios (SDR. However, there have been performance concerns since its conception. Arguably, the majority of the problems and inefficiencies associated with the SCA can be attributed to the assumption of modular distributed platforms relying on General Purpose Processors (GPPs to perform all signal processing. Approach: Significant improvements in cost and power consumption can be obtained by utilizing specialized and more efficient platforms. Digital Signal Processors (DSPs present such a platform and have been widely used in the communications industry. Improvements in development tools and middleware technology opened the possibility of fully integrating DSPs into the SCA. This approach takes advantage of the exceptional power, cost and performance characteristics of DSPs, while still enjoying the flexibility and portability of the SCA. Results: This study presents the design and implementation of an SCA Core Framework (CF for a TI TMS320C6416 DSP. The framework is deployed on a C6416 Device Cycle Accurate Simulator and TI C6416 Development board. The SCA CF is implemented by leveraging OSSIE, an open-source implementation of the SCA, to support the DSP platform. OIS’s ORBExpress DSP and DSP/BIOS are used as the middleware and operating system, respectively. A sample waveform was developed to demonstrate the framework’s functionality. Benchmark results for the framework and sample applications are provided. Conclusion: Benchmark results show that, using OIS ORBExpress DSP ORB middleware has an impact for decreasing the Software Memory Footprint and increasing the System Performance compared with PrismTech's e*ORB middleware.

  10. Temporary threshold shifts at 1500 and 2000 Hz induced by loud voice signals communicated through earphones in the pinball industry.

    Science.gov (United States)

    Idota, Nozomi; Horie, Seichi; Tsutsui, Takao; Inoue, Jinro

    2010-10-01

    To assess the risk of hearing loss among workers using earphones as communication devices at noisy worksites, we compared temporary threshold shifts (TTS) between ears on which workers wore earphones and ears on which no earphones were worn. We measured ambient noise and personal noise exposure as well as noise generated by and passed through earphones by applying frequency analysis at three pinball facilities during their hours of actual operation. We assessed hearing levels before and after a work shift (prework and postwork) of 54 workers by pure tone audiometry at six frequencies. The time-weighted averages for ambient noise and personal noise exposure exceeded 85 dB(A) and 90 dB(A), respectively. Overall sound pressure levels generated by and passing through earphones reached 109 dB(A). The one-third octave band spectrum of the earphone noise during the shift exceeded 90 dB(SPL) in the range of 315-2000 Hz. The number of ears demonstrating a TTS, defined as a shift of 10 dB or more in postwork over prework hearing thresholds, was significantly greater at 1500 and 2000 Hz among ears with earphones (P communication devices in noisy environments are exposed to high risk of hearing loss, particularly at the frequencies of 1500 and 2000 Hz. Ideally, hearing conservation programs for such workers should account for potential hearing losses at frequencies of 2000 Hz or lower frequencies induced by amplified voice signals.

  11. Ultrasonic Vocalizations by Adult Rats (Rattus norvegicus)

    Science.gov (United States)

    1991-12-01

    begun. Diazepam , chlordiazepoxide , morphine, or naloxone was administered I.P. prior to placing the rat in the tailshock apparatus. Four different...by chlordiazepoxide and diazepam . Drug Dev. Res., 5, 185-193 (1985). Gardner, C.R., and Budhram, P. Effects of agents which interact with central... diazepam , and chlorpromazine, attenuate these vocalizations. Recent work by Kaltwasser (1990) examined the occurrence of vocalizations in response to

  12. Vocal health fitness to different music styles

    Directory of Open Access Journals (Sweden)

    Maria Cláudia Mendes Caminha Muniz

    2010-09-01

    Full Text Available Objective: To present genres and styles currently running on western music scene, focusing on the practice of singing voice. Methods: An observational and documental study for which were selected sound sources presenting musical genres and styles that are part of the experience of the researchers, which were analyzed considering origins, formative elements and vocal features. Alongside we carried out a review of literature grounded in databases research and free review of websites and classical books of the area. Results: The selected styles (Rock and Roll, Heavy Metal, Trash Metal, Grunge, Gothic Metal, Rap, Funk, Blues, R&B – Rhythm and Blues, Soul, Gospel, MPB, Samba, Forro, Sertanejo, Bossa Nova, Opera and Chamber Music were described, pointing the reasons for the speech therapist to be informed about them and about singing voice aspects. His guidance may minimize possible vocal damage caused by each style, since each of them carries its own patterns to which the interpreter must submit. Conclusions: We conclude that the singer will use a specific vocal pattern that resembles the musical style he intends to sing, regardless of any harm it may or may not cause to vocal health. When choosing a musical style, it is important that the singer has the knowledge and understanding of how the use of his vocal apparatus will cause or not cause injury to his voice. Also be aware that the technique in singing is necessary for vocal longevity.

  13. Profiling the metabolic signals involved in chemical communication between microbes using imaging mass spectrometry.

    Science.gov (United States)

    Stasulli, Nikolas M; Shank, Elizabeth A

    2016-09-02

    The ability of microbes to secrete bioactive chemical signals into their environment has been known for over a century. However, it is only in the last decade that imaging mass spectrometry has provided us with the ability to directly visualize the spatial distributions of these microbial metabolites. This technology involves collecting mass spectra from multiple discrete locations across a biological sample, yielding chemical 'maps' that simultaneously reveal the distributions of hundreds of metabolites in two dimensions. Advances in microbial imaging mass spectrometry summarized here have included the identification of novel strain- or coculture-specific compounds, the visualization of biotransformation events (where one metabolite is converted into another by a neighboring microbe), and the implementation of a method to reconstruct the 3D subsurface distributions of metabolites, among others. Here we review the recent literature and discuss how imaging mass spectrometry has spurred novel insights regarding the chemical consequences of microbial interactions.

  14. Effects of speech noise on vocal fundamental frequency using power spectral analysis.

    Science.gov (United States)

    Lee, Guo-She; Hsiao, Tzu-Yu; Yang, Cheryl C H; Kuo, Terry B J

    2007-06-01

    To investigate the relationship between auditory function and vocal fundamental frequency (F0) using binaural masking with speech noise during sustained vowel vocalization. Eight healthy subjects were instructed to vocalize the sustained vowel /a/ at the intensities of 65 to 75 dBA and 90 to 100 dBA as steadily as possible. The phonations without noise masking were compared with the phonations under masking with 85-dBA speech noise presented to both ears through headphones. The F0s were obtained by using autocorrelation of the voice signals and were converted to cents to form a F0 sequence. The power spectrum of the F0 sequence was then acquired using fast Fourier transformation. A significant increase in the power spectrum in the frequency range of production by decreasing F0 modulation at production and auditory feedback.

  15. Effect of fundamental frequency at voice onset on vocal attack time.

    Science.gov (United States)

    Watson, Ben C; Baken, R J; Roark, Rick M; Reid, Stephanie; Ribeiro, Melissa; Tsai, Weilyn

    2013-05-01

    To examine vocal attack time (VAT) values associated with the production of low, mid, and high rates of vocal fold vibration in normal speakers. Sound pressure (SP) and electroglottographic (EGG) recordings were obtained for eight female and five male subjects while producing multiple tokens of the sustained vowels /ɑ/, /i/, and /u/ at comfortable loudness and at mid, low (-3 semitones), and high (+6 semitones) rates of vocal fold vibration. Generalized sinusoidal models of the SP and EGG signals were computed to compare rates of amplitude change. VAT was computed from the time lag of the cross-correlation function. Adjusted mean VAT for the high frequency condition was smaller than the adjusted mean VAT values for the low- and mid-frequency conditions. There was no significant difference between the mid and low frequency conditions. Findings reveal an association of the VAT measure with increases in vocal fold tension associated with the production of high rates of vocal fold vibration. Copyright © 2013 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  16. Peripheral androgen action helps modulate vocal production in a suboscine passerine.

    Science.gov (United States)

    Fuxjager, Matthew J; Heston, Jonathan B; Schlinger, Barney A

    2014-07-01

    Androgenic activation of intracellular androgen receptors (AR) influences avian vocal production, though this has largely been investigated at the level of the brain. We investigated the influence of predominantly peripheral AR on vocal output in wild Golden-collared Manakins (Manacus vitellinus). In this suboscine species, males court females by performing acrobatic displays and by producing relatively simple chee-poo vocalizations. To assess whether peripheral AR influences the acoustic structure of these vocal signals, we treated reproductively active adult males with the peripherally selective antiandrogen bicalutamide and then measured phonation performance. Inhibiting AR outside of the central nervous system increased the duration of the chee note and decreased the fundamental frequency of the poo note. This treatment caused no discernable change to chee-poo frequency modulation or entropy. Our results show that activation of peripheral AR mediates note-specific changes to temporal and pitch characteristics of the Golden-collared Manakin's main sexual call. Thus, our study provides one of the first demonstrations that androgenic action originating outside of the brain and likely on musculoskeletal targets can modulate avian vocal production.

  17. On Short-Time Estimation of Vocal Tract Length from Formant Frequencies.

    Directory of Open Access Journals (Sweden)

    Adam C Lammert

    Full Text Available Vocal tract length is highly variable across speakers and determines many aspects of the acoustic speech signal, making it an essential parameter to consider for explaining behavioral variability. A method for accurate estimation of vocal tract length from formant frequencies would afford normalization of interspeaker variability and facilitate acoustic comparisons across speakers. A framework for considering estimation methods is developed from the basic principles of vocal tract acoustics, and an estimation method is proposed that follows naturally from this framework. The proposed method is evaluated using acoustic characteristics of simulated vocal tracts ranging from 14 to 19 cm in length, as well as real-time magnetic resonance imaging data with synchronous audio from five speakers whose vocal tracts range from 14.5 to 18.0 cm in length. Evaluations show improvements in accuracy over previously proposed methods, with 0.631 and 1.277 cm root mean square error on simulated and human speech data, respectively. Empirical results show that the effectiveness of the proposed method is based on emphasizing higher formant frequencies, which seem less affected by speech articulation. Theoretical predictions of formant sensitivity reinforce this empirical finding. Moreover, theoretical insights are explained regarding the reason for differences in formant sensitivity.

  18. Social complexity parallels vocal complexity: a comparison of three nonhuman primate species

    Directory of Open Access Journals (Sweden)

    Hélène eBOUCHET

    2013-07-01

    Full Text Available Social factors play a key role in the structuring of vocal repertoires at the individual level, notably in nonhuman primates. Some authors suggested that, at the species level too, social life may have driven the evolution of communicative complexity, but this has rarely been empirically tested. Here, we use a comparative approach to address this issue. We investigated vocal variability, at both the call type and the repertoire levels, in three forest-dwelling species of Cercopithecinae presenting striking differences in their social systems, in terms of social organization as well as social structure. We collected female call recordings from twelve De Brazza’s monkeys (Cercopithecus neglectus, six Campbell’s monkeys (Cercopithecus campbelli and seven red-capped mangabeys (Cercocebus torquatus housed in similar conditions. First, we noted that the level of acoustic variability and individual distinctiveness found in several call types was related to their importance in social functioning. Contact calls, essential to intra-group cohesion, were the most individually distinctive regardless of the species, while threat calls were more structurally variable in mangabeys, the most ‘despotic’ of our three species. Second, we found a parallel between the degree of complexity of the species’ social structure and the size, diversity, and usage of its vocal repertoire. Mangabeys (most complex social structure called twice as often as guenons and displayed the largest and most complex repertoire. De Brazza’s monkeys (simplest social structure displayed the smallest and simplest repertoire. Campbell’s monkeys displayed an intermediate pattern. Providing evidence of higher levels of vocal variability in species presenting a more complex social system, our results are in line with the theory of a social-vocal coevolution of communicative abilities, opening new perspectives for comparative research on the evolution of communication systems in

  19. Grunt communication in human infants (Homo sapiens).

    Science.gov (United States)

    McCune, L; Vihman, M M; Roug-Hellichius, L; Delery, D B; Gogate, L

    1996-03-01

    Laryngeally produced vocalizations termed grunts function communicatively in many species. The vocalizations and accompanying behavior of 5 human infants videorecorded monthly at the transition to speech were analyzed to determine the frequency, physiological basis, and functional status of grunt production, a phenomenon systematically studied for the first time here. Earliest grunts occurred accompanying movement or effort; next, they accompanied acts of focal attention; and finally they were used in communication. Communicative use was followed by the onset of referential ability in language. This sequence is interpreted in relation to the physiological basis of these vocalizations in respiratory function and to additional developmental variables observed in the children. The findings have implications for the transition to the communicative repertoire in other species in which laryngeal function contributes to communication.

  20. Segmentation of Killer Whale Vocalizations Using the Hilbert-Huang Transform

    Directory of Open Access Journals (Sweden)

    Olivier Adam

    2008-08-01

    Full Text Available The study of cetacean vocalizations is usually based on spectrogram analysis. The feature extraction is obtained from 2D methods like the edge detection algorithm. Difficulties appear when signal-to-noise ratios are weak or when more than one vocalization is simultaneously emitted. This is the case for acoustic observations in a natural environment and especially for the killer whales which swim in groups. To resolve this problem, we propose the use of the Hilbert-Huang transform. First, we illustrate how few modes (5 are satisfactory for the analysis of these calls. Then, we detail our approach which consists of combining the modes for extracting the time-varying frequencies of the vocalizations. This combination takes advantage of one of the empirical mode decomposition properties which is that the successive IMFs represent the original data broken down into frequency components from highest to lowest frequency. To evaluate the performance, our method is first applied on the simulated chirp signals. This approach allows us to link one chirp to one mode. Then we apply it on real signals emitted by killer whales. The results confirm that this method is a favorable alternative for the automatic extraction of killer whale vocalizations.

  1. The performance of methods based on the fractional Fourier transform for detecting marine mammal vocalizations.

    Science.gov (United States)

    Locke, Jonathan; White, Paul R

    2011-10-01

    The analysis of cetacean vocalizations is considered using Fourier-based techniques that employ chirp functions in their decomposition. In particular, the paper considers a short-time methods based on the fractional Fourier transform for detecting frequency modulated narrow-band signals, such as dolphin whistles, and compares this to the classical short-time Fourier methods. The fractional Fourier technique explored computes transforms associated with a range of chirp rates and automatically selects the rate for the final analysis. This avoids the need for prior knowledge of signal's chirp rate. An analysis is presented that details the performance of both methods as signal detectors and allows one to determine their detection thresholds. These thresholds are then used to measure the detectability of synthetic signals. This principle is then extended to measure performance on a set of recordings of narrow-band vocalizations from a range of cetacean species.

  2. Voice analysis before and after vocal rehabilitation in patients following open surgery on vocal cords

    Directory of Open Access Journals (Sweden)

    Bunijevac Mila

    2016-01-01

    Full Text Available Background/Aim. The major role of larynx in speech, respiration and swallowing makes carcinomas of this region and their treatment very influential for patients’ life quality. The aim of this study was to assess the importance of voice therapy in patients after open surgery on vocal cords. Methods. This study included 21 male patients and the control group of 19 subjects. The vowel (A was recorded and analyzed for each examinee. All the patients were recorded twice: firstly, when they contacted the clinic and secondly, after a three-month vocal therapy, which was held twice per week on an outpatient basis. The voice analysis was carried out in the Ear, Nose and Throat (ENT Clinic, Clinical Hospital Center “Zvezdara” in Belgrade. Results. The values of the acoustic parameters in the patients submitted to open surgery on the vocal cords before vocal rehabilitation and the control group subjects were significantly different in all specified parameters. These results suggest that the voice of the patients was damaged before vocal rehabilitation. The results of the acoustic parameters of the vowel (A before and after vocal rehabilitation of the patients with open surgery on vocal cords were statistically significantly different. Among the parameters - Jitter (%, Shimmer (% - the observed difference was highly statistically significant (p 0.05 . Conclusion. There was a significant improvement of the acoustic parameters of the vowel (A in the study subjects three months following vocal therapy. Only one out of five representative parameters showed no significant improvement.

  3. Stimulation of the Basal and Central Amygdala in the Mustached Bat Triggers Echolocation and Agonistic Vocalizations within Multimodal Output

    Directory of Open Access Journals (Sweden)

    Jie eMa

    2014-03-01

    Full Text Available The neural substrate for the perception of vocalization is relatively well described, but we know much less about how the timing and specificity of vocalizations is tightly coupled with audiovocal communication behavior. In many vocal species, well-timed vocalizations accompany fear, vigilance and aggression. These emotive responses likely originate within the amygdala and other limbic structures, but the organization of motor outputs for triggering species-appropriate behaviors remains unclear. We performed electrical microstimulation at 461 highly restricted loci within the basal and central amygdala in awake mustached bats. At a subset of these sites, high frequency stimulation with weak constant current pulses presented at near-threshold levels triggered vocalization of either echolocation pulses or social calls. At the vast majority of locations, microstimulation produced a constellation of changes in autonomic and somatomotor outputs. These changes included widespread co-activation of significant tachycardia and hyperventilation and/or rhythmic ear pinna movements. In a few locations, responses were constrained to vocalization and/or pinna movements despite increases in the intensity of stimulation. The probability of eliciting echolocation pulses versus social calls decreased in a medial-posterior to anterolateral direction within the centrobasal amygdala. Microinjections of kainic acid at stimulation sites confirmed the contribution of cellular activity rather than fibers-of-passage in the control of multimodal outputs. The results suggest that multimodal clusters of neurons may simultaneously modulate the activity of multiple central pattern generators present within the brainstem.

  4. VOCALIZATIONS AND ASSOCIATED BEHAVIORS OF THE SOMBRE HUMMINGBIRD (APHANTOCHROA CIRRHOCHLORIS) AND THE RUFOUS-BREASTED HERMIT (GLAUCIS HIRSUTUS)

    Science.gov (United States)

    Ferreira, Adriana R. J.; Smulders, Tom V.; Sameshima, Koichi; Mello, Claudio V.; Jarvis, Erich D.

    2008-01-01

    Vocal behavior in tropical hummingbirds is a new area of study. Here, we present findings on the vocalizations and associated behaviors of two species: Sombre Hummingbird (Aphantochroa cirrhochloris) and Rufous-breasted Hermit (Glaucis hirsutus). These are the only hummingbirds in which the brain areas activated by singing have been demonstrated. They are also among the basal species of their respective subfamilies, Trochilinae and Phaethornithinae and, thus, represent early stages in the evolution of hummingbird vocal communication. We found that the two species exhibit distinctive vocalizations and behaviors. Sombre Hummingbird calls had more modulation and were often used during agonistic interactions, whereas Rufous-breasted Hermit calls had higher pitch and purer tones and were produced in less aggressive interactions. Sombre Hummingbird song was highly stereotyped in syllable structure and syntax, whereas Rufous-breasted Hermit song was highly variable. Comparative analysis points to consistent similarities in use of vocalizations by the Sombre Hummingbird and other trochilines, and by the Rufous-breasted Hermit and other phaethornithines. We hypothesize that differences in vocal behavior between hummingbird lineages arise as adaptations to their foraging strategies. PMID:18802498

  5. Synaptic communication and signal processing among sensory cells in taste buds

    Science.gov (United States)

    Chaudhari, Nirupa

    2014-01-01

    Taste buds (sensory structures embedded in oral epithelium) show a remarkable diversity of transmitters synthesized and secreted locally. The known transmitters accumulate in a cell type selective manner, with 5-HT and noradrenaline being limited to presynaptic cells, GABA being synthesized in both presynaptic and glial-like cells, and acetylcholine and ATP used for signalling by receptor cells. Each of these transmitters participates in local negative or positive feedback circuits that target particular cell types. Overall, the role of ATP is the best elucidated. ATP serves as a principal afferent transmitter, and also is the key trigger for autocrine positive feedback and paracrine circuits that result in potentiation (via adenosine) or inhibition (via GABA or 5-HT). While many of the cellular receptors and mechanisms for these circuits are known, their impact on sensory detection and perception remains to be elaborated in most instances. This brief review examines what is known, and some of the open questions and controversies surrounding the transmitters and circuits of the taste periphery. PMID:24665098

  6. High speed digital phonoscopy of selected extreme vocalization (Conference Presentation)

    Science.gov (United States)

    Izdebski, Krzysztof; Blanco, Matthew; Di Lorenzo, Enrico; Yan, Yuling

    2017-02-01

    We used HSDP (KayPENTAX Model 9710, NJ, USA) to capture the kinematics of vocal folds in the production of extreme vocalization used by heavy metal performers. The vibrations of the VF were captured at 4000 f/s using transoral rigid scope. Growl, scream and inhalatory phonations were recoded. Results showed that these extreme sounds are produced predominantly by supraglottic tissues rather than by the true vocal folds, which explains while these sounds do not injure the mucosa of the true vocal folds. In addition, the HSDI were processed using custom software (Vocalizer®) that clearly demonstrated the contribution of each vocal fold to the generation of the sound.

  7. Social-bond strength influences vocally mediated recruitment to mobbing.

    Science.gov (United States)

    Kern, Julie M; Radford, Andrew N

    2016-11-01

    Strong social bonds form between individuals in many group-living species, and these relationships can have important fitness benefits. When responding to vocalizations produced by groupmates, receivers are expected to adjust their behaviour depending on the nature of the bond they share with the signaller. Here we investigate whether the strength of the signaller-receiver social bond affects response to calls that attract others to help mob a predator. Using field-based playback experiments on a habituated population of wild dwarf mongooses (Helogale parvula), we first demonstrate that a particular vocalization given on detecting predatory snakes does act as a recruitment call; receivers were more likely to look, approach and engage in mobbing behaviour than in response to control close calls. We then show that individuals respond more strongly to these recruitment calls if they are from groupmates with whom they are more strongly bonded (those with whom they preferentially groom and forage). Our study, therefore, provides novel evidence about the anti-predator benefits of close bonds within social groups.

  8. Correlation between vocal functions and glottal measurements in patients with unilateral vocal fold paralysis.

    Science.gov (United States)

    Inagi, K; Khidr, A A; Ford, C N; Bless, D M; Heisey, D M

    1997-06-01

    Observations and analysis of glottal characteristics are critical in choosing the best modality for surgery in patients with unilateral vocal fold paralysis (UVP). This study suggests that multiple glottal characteristics influence the vocal product in patients with UVP. In addition to the horizontal position of the paralyzed vocal fold (deviation from the midline), the glottal area, degree of bowing of the paralyzed and contralateral vocal folds, maximum separation between vocal folds, compensatory glottal maneuvers, and the vertical glottic closure plane significantly influenced the quality of the voice. Clinicians should be aware of these observations to facilitate treatment planning and assessment of the results of surgical procedures used to improve voice quality in cases of UVP.

  9. At the interface of the auditory and vocal motor systems: NIf and its role in vocal processing, production and learning.

    Science.gov (United States)

    Lewandowski, Brian; Vyssotski, Alexei; Hahnloser, Richard H R; Schmidt, Marc

    2013-06-01

    Communication between auditory and vocal motor nuclei is essential for vocal learning. In songbirds, the nucleus interfacialis of the nidopallium (NIf) is part of a sensorimotor loop, along with auditory nucleus avalanche (Av) and song system nucleus HVC, that links the auditory and song systems. Most of the auditory information comes through this sensorimotor loop, with the projection from NIf to HVC representing the largest single source of auditory information to the song system. In addition to providing the majority of HVC's auditory input, NIf is also the primary driver of spontaneous activity and premotor-like bursting during sleep in HVC. Like HVC and RA, two nuclei critical for song learning and production, NIf exhibits behavioral-state dependent auditory responses and strong motor bursts that precede song output. NIf also exhibits extended periods of fast gamma oscillations following vocal production. Based on the converging evidence from studies of physiology and functional connectivity it would be reasonable to expect NIf to play an important role in the learning, maintenance, and production of song. Surprisingly, however, lesions of NIf in adult zebra finches have no effect on song production or maintenance. Only the plastic song produced by juvenile zebra finches during the sensorimotor phase of song learning is affected by NIf lesions. In this review, we carefully examine what is known about NIf at the anatomical, physiological, and behavioral levels. We reexamine conclusions drawn from previous studies in the light of our current understanding of the song system, and establish what can be said with certainty about NIf's involvement in song learning, maintenance, and production. Finally, we review recent theories of song learning integrating possible roles for NIf within these frameworks and suggest possible parallels between NIf and sensorimotor areas that form part of the neural circuitry for speech processing in humans.

  10. Strategy for signaling molecule detection by using an integrated microfluidic device coupled with mass spectrometry to study cell-to-cell communication.

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    Mao, Sifeng; Zhang, Jie; Li, Haifang; Lin, Jin-Ming

    2013-01-15

    Cell-to-cell communication is a very important physiological behavior in life entity, and most of human behaviors are related to it. Although cell-to-cell communications are attracting much attention and financial support, rare methods have been successfully developed for in vitro cell-to-cell communication study. In this work, we developed a novel method for cell-to-cell communication study on an integrated microdevice, and signaling molecule and metabolites were online-detected by an electrospray ionization-quadrupole-time-of-flight-mass spectrometer (ESI-Q-TOF-MS) after on-chip solid-phase extraction. Moreover, we presented a "Surface Tension Plug" on a microchip to control cell-to-cell communication. The microdevice consists of three functional sections: cell coculture channel, targets pretreatment, and targets detection sections. To verify the feasibility of cell-to-cell communications on the integrated microdevice, we studied the communication between the 293 and the L-02 cells. Epinephrine and glucose were successfully detected using an ESI-Q-TOF-MS with short analysis time (communication study.

  11. Stuttering: A novel bullfrog vocalization

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    Simmons, Andrea; Suggs, Dianne

    2004-05-01

    The advertisement call of male bullfrogs (Rana catesbeiana) consists of a series of individual croaks, each of which contains multiple harmonics with a missing or attenuated fundamental frequency of approximately 100 Hz. The envelope of individual croaks has typically been represented in the literature as smooth and unmodulated. From an analysis of 5251 advertisement calls from 17 different choruses over two mating seasons, we show that males add an extra modulation (around 4 Hz) to the envelope of individual croaks, following specific rules. We term these extra modulations stutters. Neither single croak calls nor the first croak in multiple croak calls contains stutters. When stuttering begins, it does so with a croak containing a single stutter, and the number of stutters increases linearly (plus or minus 1 stutter, up to 4 stutters) with the number of croaks. This pattern is stable across individual males (N=10). Playback experiments reveal that vocal responses to stuttered and nonstuttered calls vary with proximity to the stimulus. Close males respond with nonstuttered calls, while far males respond with stuttered calls. The data suggest that nonstuttered calls are used for aggressive or territorial purposes, while stuttered calls are used to attract females.

  12. Vocal cord paralysis in children.

    Science.gov (United States)

    King, Ericka F; Blumin, Joel H

    2009-12-01

    Vocal fold paralysis (VFP) is an increasingly commonly identified problem in the pediatric patient. Diagnostic and management techniques honed in adult laryngologic practice have been successfully applied to children. Iatrogenic causes, including cardiothoracic procedures, remain a common cause of unilateral VFP. Neurologic disorders predominate in the cause of bilateral VFP. Diagnosis with electromyography is currently being evaluated in children. Treatment of VFP is centered around symptomology, which is commonly divided between voice and airway concerns. Speech therapy shows promise in older children. Surgical management for unilateral VFP with injection laryngoplasty is commonly performed and well tolerated. Laryngeal reinnervation is currently being applied to the pediatric population as a permanent treatment and offers several advantages over laryngeal framework procedures. For bilateral VFP, tracheotomy is still commonly performed. Glottic dilation procedures are performed both openly and endoscopically with a high degree of success. VFP is a well recognized problem in pediatric patients with disordered voice and breathing. Some patients will spontaneously recover their laryngeal function. For those who do not, a variety of reliable techniques are available for rehabilitative treatment.

  13. Elaborate Mimetic Vocal Displays by Female Superb Lyrebirds

    Directory of Open Access Journals (Sweden)

    Anastasia H Dalziell

    2016-04-01

    Full Text Available Some of the most striking vocalizations in birds are made by males that incorporate vocal mimicry in their sexual displays. Mimetic vocalization in females is largely undescribed, but it is unclear whether this is because of a lack of selection for vocal mimicry in females, or whether the phenomenon has simply been overlooked. These issues are thrown into sharp relief in the superb lyrebird, Menura novaehollandiae, a basal oscine passerine with a lek-like mating system and female uniparental care. The spectacular mimetic song display produced by courting male lyrebirds is a textbook example of a sexually selected trait, but the vocalizations of female lyrebirds are largely unknown. Here, we provide the first analysis of the structure and context of the vocalizations of female lyrebirds. Female lyrebirds were completely silent during courtship; however, females regularly produced sophisticated vocal displays incorporating both lyrebird-specific vocalizations and imitations of sounds within their environment. The structure of female vocalizations varied significantly with context. While foraging, females mostly produced a complex lyrebird-specific song, whereas they gave lyrebird-specific alarm calls most often during nest defense. Within their vocal displays females also included a variety of mimetic vocalizations, including imitations of the calls of dangerous predators, and of alarm calls and song of harmless heterospecifics. Females gave more mimetic vocalizations during nest defense than while foraging, and the types of sounds they imitated varied between these contexts, suggesting that mimetic vocalizations have more than one function. These results are inconsistent with previous portrayals of vocalizations by female lyrebirds as rare, functionless by-products of sexual selection on males. Instead, our results support the hypotheses that complex female vocalizations play a role in nest defense and mediate female-female competition for

  14. Information theory, animal communication, and the search for extraterrestrial intelligence

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    Doyle, Laurance R.; McCowan, Brenda; Johnston, Simon; Hanser, Sean F.

    2011-02-01

    We present ongoing research in the application of information theory to animal communication systems with the goal of developing additional detectors and estimators for possible extraterrestrial intelligent signals. Regardless of the species, for intelligence (i.e., complex knowledge) to be transmitted certain rules of information theory must still be obeyed. We demonstrate some preliminary results of applying information theory to socially complex marine mammal species (bottlenose dolphins and humpback whales) as well as arboreal squirrel monkeys, because they almost exclusively rely on vocal signals for their communications, producing signals which can be readily characterized by signal analysis. Metrics such as Zipf's Law and higher-order information-entropic structure are emerging as indicators of the communicative complexity characteristic of an "intelligent message" content within these animals' signals, perhaps not surprising given these species' social complexity. In addition to human languages, for comparison we also apply these metrics to pulsar signals—perhaps (arguably) the most "organized" of stellar systems—as an example of astrophysical systems that would have to be distinguished from an extraterrestrial intelligence message by such information theoretic filters. We also look at a message transmitted from Earth (Arecibo Observatory) that contains a lot of meaning but little information in the mathematical sense we define it here. We conclude that the study of non-human communication systems on our own planet can make a valuable contribution to the detection of extraterrestrial intelligence by providing quantitative general measures of communicative complexity. Studying the complex communication systems of other intelligent species on our own planet may also be one of the best ways to deprovincialize our thinking about extraterrestrial communication systems in general.

  15. A fast BK-type KCa current acts as a postsynaptic modulator of temporal selectivity for communication signals

    Directory of Open Access Journals (Sweden)

    Tsunehiko eKohashi

    2014-09-01

    Full Text Available Temporal patterns of spiking often convey behaviorally relevant information. Various synaptic mechanisms and intrinsic membrane properties can influence neuronal selectivity to temporal patterns of input. However, little is known about how synaptic mechanisms and intrinsic properties together determine the temporal selectivity of neuronal output. We tackled this question by recording from midbrain electrosensory neurons in mormyrid fish, in which the processing of temporal intervals between communication signals can be studied in a reduced in vitro preparation. Mormyrids communicate by varying interpulse intervals (IPIs between electric pulses. Within the midbrain posterior exterolateral nucleus (ELp, the temporal patterns of afferent spike trains are filtered to establish single-neuron IPI tuning. We performed whole-cell recording from ELp neurons in a whole-brain preparation and examined the relationship between intrinsic excitability and IPI tuning. We found that spike frequency adaptation of ELp neurons was highly variable. Postsynaptic potentials (PSPs of strongly adapting (phasic neurons were more sharply tuned to IPIs than weakly adapting (tonic neurons. Further, the synaptic filtering of IPIs by tonic neurons was more faithfully converted into variation in spiking output, particularly at short IPIs. Pharmacological manipulation under current- and voltage-clamp revealed that tonic firing is mediated by a fast, large-conductance Ca2+-activated K+ (KCa current (BK that speeds up action potential repolarization. These results suggest that BK currents can shape the temporal filtering of sensory inputs by modifying both synaptic responses and PSP-to-spike conversion. Slow SK-type KCa currents have previously been implicated in temporal processing. Thus, both fast and slow KCa currents can fine-tune temporal selectivity.

  16. Estimation of Potential Interference Immunity of Radio Reception with Spatial Signal Processing in Mutipath Radio-Communication Channels. Part II. Meter and Decimeter Ranges

    Science.gov (United States)

    Lvov, A. V.; Metelev, S. L.

    2016-11-01

    We propose simulation models for estimating the interference immunity of radio reception using the spatial processing of signals in the airborne and ground-based communication channels of the meter and decimeter wavelength ranges. The ultimate achievable interference immunity under various radio-wave propagation conditions is studied.

  17. Estimation of the Potential Interference Immunity of Radio Reception with Spatial Signal Processing in Multipath Radio-Communication Channels. I. Decameter Range

    Science.gov (United States)

    Metelev, S. A.; Lvov, A. V.

    2016-09-01

    We propose a method for estimating potential interference immunity of radio reception in the multipath radio-communication channels. Using this method for the modified Watterson model of the decameter radio channel, we study the achievable interference immunity of devices with spatial signal processing.

  18. Comparison of St. Lawrence blue whale vocalizations with field observations

    Science.gov (United States)

    Berchok, Catherine; Bradley, David; Gabrielson, Thomas; Sears, Richard

    2003-04-01

    During four field seasons from 1998-2001, vocalizations were recorded in the presence of St. Lawrence blue whales using a single omni-directional hydrophone. Both long duration infrasonic calls (~18 Hz, 5-20 s) as well as short duration higher frequency calls (85-25 Hz, ~2 s) were detected and compared with field observations. Two trends were noted. First, the long infrasonic call series were concentrated primarily in the deep (300 m) channel. These call series appear to compare well with blue whale vocalizations recorded by others in the deep open ocean. Second, the shorter audible calls were more evenly distributed over bathymetry and seem to be a form of short distance communication with at least one case occurring during an agonistic interaction. A comparison of these calls with biological parameters such as density of whales in the area, percentages of paired versus single whales, and numbers of males versus females will also be discussed. [Project supported by ARL/PSU, NSF, and the American Museum of Natural History.

  19. Viscoelastic properties of the false vocal fold

    Science.gov (United States)

    Chan, Roger W.

    2004-05-01

    The biomechanical properties of vocal fold tissues have been the focus of many previous studies, as vocal fold viscoelasticity critically dictates the acoustics and biomechanics of phonation. However, not much is known about the viscoelastic response of the ventricular fold or false vocal fold. It has been shown both clinically and in computer simulations that the false vocal fold may contribute significantly to the aerodynamics and sound generation processes of human voice production, with or without flow-induced oscillation of the false fold. To better understand the potential role of the false fold in phonation, this paper reports some preliminary measurements on the linear and nonlinear viscoelastic behavior of false vocal fold tissues. Linear viscoelastic shear properties of human false fold tissue samples were measured by a high-frequency controlled-strain rheometer as a function of frequency, and passive uniaxial tensile stress-strain response of the tissue samples was measured by a muscle lever system as a function of strain and loading rate. Elastic moduli (Young's modulus and shear modulus) of the false fold tissues were calculated from the measured data. [Work supported by NIH.

  20. Vocal effort and voice handicap among teachers.

    Science.gov (United States)

    Sampaio, Márcio Cardoso; dos Reis, Eduardo José Farias Borges; Carvalho, Fernando Martins; Porto, Lauro Antonio; Araújo, Tânia Maria

    2012-11-01

    The relationship between voice handicap and professional vocal effort was investigated among teachers in a cross-sectional study of census nature on 4496 teachers within the public elementary education network in Salvador, Bahia, Brazil. Voice handicap (the outcome of interest) was evaluated using the Voice Handicap Index 10. The main exposure, the lifetime vocal effort index, was obtained as the product of the number of years working as a teacher multiplied by the mean weekly working hours. The prevalence of voice handicap was 28.8% among teachers with high professional vocal effort and 21.3% among those with acceptable vocal effort, thus yielding a crude prevalence ratio (PR) of 1.36 (95% confidence interval [CI]=1.14-1.61). In the final logistic model, the prevalence of voice handicap was statistically associated with the professional vocal effort index (PR=1.47; 95% CI=1.19-1.82), adjusted according to sex, microphone availability in the classroom, excessive noise, pressure from the school management, heartburn, and rhinitis.