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Sample records for semilunar courtship rhythm

  1. Cysts of the semilunar cartilage

    International Nuclear Information System (INIS)

    Bruessermann, M.

    1981-01-01

    On the basis of the studies listed in the bibliography, this dissertation reports on the pathology, clinical symptoms and radiology of cysts of the semilunar cartilage. The author analyses 118 cases of his own, with special regard to the results of pneumo-arthrographic investigations carried through according to a special technique by Schaefer. In the course of this work, measurements of the meniscal base are for the first time used as radiological criteria indicating the presence of a cyst of the semilunar cartilage. Furthermore the well-known radiological signs of cysts, such as bone defects according to Albert and Keller, light central spot in the meniscal body, as well as Rauber's sign and horizontal rupture, are investigated as to the frequency of their incidence. For that purpose all the X-ray pictures were subjected to a further dose scrutiny. A list of all the 118 cases with their clinical and radiological data is found in the annex, together with the results of the operations and patho-anatomical investigations. (orig.) [de

  2. Courtship in Frogs

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 12. Courtship in Frogs Role of Acoustic Communication in Amphibian Courtship Behaviour. Debjani Roy. General Article Volume 1 Issue 12 December 1996 pp 39-48 ...

  3. Fan-Shaped Body Neurons Are Involved in "Period"-Dependent Regulation of Long-Term Courtship Memory in "Drosophila"

    Science.gov (United States)

    Sakai, Takaomi; Inami, Show; Sato, Shoma; Kitamoto, Toshihiro

    2012-01-01

    In addition to its established function in the regulation of circadian rhythms, the "Drosophila" gene "period" ("per") also plays an important role in processing long-term memory (LTM). Here, we used courtship conditioning as a learning paradigm and revealed that (1) overexpression and knocking down of "per" in subsets of brain neurons enhance and…

  4. Motor Control of Drosophila Courtship Song

    Directory of Open Access Journals (Sweden)

    Troy R. Shirangi

    2013-11-01

    Full Text Available Many animals utilize acoustic signals—or songs—to attract mates. During courtship, Drosophila melanogaster males vibrate a wing to produce trains of pulses and extended tone, called pulse and sine song, respectively. Courtship songs in the genus Drosophila are exceedingly diverse, and different song features appear to have evolved independently of each other. How the nervous system allows such diversity to evolve is not understood. Here, we identify a wing muscle in D. melanogaster (hg1 that is uniquely male-enlarged. The hg1 motoneuron and the sexually dimorphic development of the hg1 muscle are required specifically for the sine component of the male song. In contrast, the motoneuron innervating a sexually monomorphic wing muscle, ps1, is required specifically for a feature of pulse song. Thus, individual wing motor pathways can control separate aspects of courtship song and may provide a “modular” anatomical substrate for the evolution of diverse songs.

  5. [The injection of acrylic bone cement prevents bone collapse in the intercalar bones lacking bony support: an experimental sheep semilunar bone model].

    Science.gov (United States)

    Unsal, Murat; Tetik, Cihangir; Erol, Bülent; Cabukoğlu, Cengiz

    2003-01-01

    In a sheep semilunar bone model, we investigated whether collapse in the intercalar bones lacking bony support could be prevented by the injection of acrylic bone cement. The study included 16 limbs of eight sheep. Preoperatively, anteroposterior and lateral views of the carpal joints in the fore limbs were obtained. The animals were divided into four groups. In group 1 (n=3) no surgical procedure was performed in the right semilunar bones, whereas the periosteum on the contralateral side was elevated (group 2; n=3). The first two groups were left as controls. In Group 3 (n=5) the left semilunar bones were filled with acrylic bone cement following decancellation of the bone, while the right semilunar bones were left decancellated (group 4; n=5). The sheep were monitored for three months. Radiographs of the carpal joints were obtained to evaluate collapse occurrence in the semilunar bones. Thereafter, the animals were sacrificed and the semilunar bones were excised for biomechanical and histological examinations. Osteonecrosis and cartilage damage were sought and resistance to compressive forces was investigated. Radiologically, the extent of collapse was statistically significant in the semilunar bones in group 4 (pbone cement was found to prevent collapse in group 3, with no significant difference being noted between preoperative and postoperative semilunar bone heights (p>0.05). Biomechanically, the least resistance to compressive forces was measured in group 4 (pbone cement prevents collapse in the semilunar bones, without inducing any cartilage damage or osteonecrosis.

  6. Circadian Rhythms

    Indian Academy of Sciences (India)

    IAS Admin

    thus appear to be simple responses of living beings to cyclic presence/absence of ... For example, during leaf movement rhythms, leaves alternate between open and closed states .... gist of his time, in an elegant experiment (Box 2) to study the navigational .... diurnal rhythms as true biological timekeepers, a question which.

  7. Circadian Rhythms

    Indian Academy of Sciences (India)

    IAS Admin

    and clocks driving such rhythms have been studied for a long time now, our ... passage of time using near 24 h oscillation as a reference process, and (iii) Output .... Bünning's work on circadian rhythms across model systems ranging from ..... E Bünning, The Physiological Clock, Revised 3rd Edition, The English. Universities ...

  8. Social Factor and Victim-Offender Differences in Courtship Violence.

    Science.gov (United States)

    Makepeace, James M.

    1987-01-01

    Explored social factor differences between respondents with and without courtship violence experience and between male offenders and female victims. Data from the Seven College Survey revealed that those with courtship violence experience exhibited relatively "problematic" social profiles. Especially significant were race; religion;…

  9. Circadian Rhythms

    Indian Academy of Sciences (India)

    IAS Admin

    nature of the system underlying such rhythms and inspired one of the ... behaviours and physiological processes were discovered in a wide range of animals. ... is thought to coordinate internal physiology, and thereby confer benefits to living ...

  10. Sensory integration regulating male courtship behavior in Drosophila.

    Directory of Open Access Journals (Sweden)

    Dimitrije Krstic

    Full Text Available The courtship behavior of Drosophila melanogaster serves as an excellent model system to study how complex innate behaviors are controlled by the nervous system. To understand how the underlying neural network controls this behavior, it is not sufficient to unravel its architecture, but also crucial to decipher its logic. By systematic analysis of how variations in sensory inputs alter the courtship behavior of a naïve male in the single-choice courtship paradigm, we derive a model describing the logic of the network that integrates the various sensory stimuli and elicits this complex innate behavior. This approach and the model derived from it distinguish (i between initiation and maintenance of courtship, (ii between courtship in daylight and in the dark, where the male uses a scanning strategy to retrieve the decamping female, and (iii between courtship towards receptive virgin females and mature males. The last distinction demonstrates that sexual orientation of the courting male, in the absence of discriminatory visual cues, depends on the integration of gustatory and behavioral feedback inputs, but not on olfactory signals from the courted animal. The model will complement studies on the connectivity and intrinsic properties of the neurons forming the circuitry that regulates male courtship behavior.

  11. Recurring ethanol exposure induces disinhibited courtship in Drosophila.

    Directory of Open Access Journals (Sweden)

    Hyun-Gwan Lee

    Full Text Available Alcohol has a strong causal relationship with sexual arousal and disinhibited sexual behavior in humans; however, the physiological support for this notion is largely lacking and thus a suitable animal model to address this issue is instrumental. We investigated the effect of ethanol on sexual behavior in Drosophila. Wild-type males typically court females but not males; however, upon daily administration of ethanol, they exhibited active intermale courtship, which represents a novel type of behavioral disinhibition. The ethanol-treated males also developed behavioral sensitization, a form of plasticity associated with addiction, since their intermale courtship activity was progressively increased with additional ethanol experience. We identified three components crucial for the ethanol-induced courtship disinhibition: the transcription factor regulating male sex behavior Fruitless, the ABC guanine/tryptophan transporter White and the neuromodulator dopamine. fruitless mutant males normally display conspicuous intermale courtship; however, their courtship activity was not enhanced under ethanol. Likewise, white males showed negligible ethanol-induced intermale courtship, which was not only reinstated but also augmented by transgenic White expression. Moreover, inhibition of dopamine neurotransmission during ethanol exposure dramatically decreased ethanol-induced intermale courtship. Chronic ethanol exposure also affected a male's sexual behavior toward females: it enhanced sexual arousal but reduced sexual performance. These findings provide novel insights into the physiological effects of ethanol on sexual behavior and behavioral plasticity.

  12. Courtship initiation is stimulated by acoustic signals in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Aki Ejima

    2008-09-01

    Full Text Available Finding a mating partner is a critical task for many organisms. It is in the interest of males to employ multiple sensory modalities to search for females. In Drosophila melanogaster, vision is thought to be the most important courtship stimulating cue at long distance, while chemosensory cues are used at relatively short distance. In this report, we show that when visual cues are not available, sounds produced by the female allow the male to detect her presence in a large arena. When the target female was artificially immobilized, the male spent a prolonged time searching before starting courtship. This delay in courtship initiation was completely rescued by playing either white noise or recorded fly movement sounds to the male, indicating that the acoustic and/or seismic stimulus produced by movement stimulates courtship initiation, most likely by increasing the general arousal state of the male. Mutant males expressing tetanus toxin (TNT under the control of Gr68a-GAL4 had a defect in finding active females and a delay in courtship initiation in a large arena, but not in a small arena. Gr68a-GAL4 was found to be expressed pleiotropically not only in putative gustatory pheromone receptor neurons but also in mechanosensory neurons, suggesting that Gr68a-positive mechanosensory neurons, not gustatory neurons, provide motion detection necessary for courtship initiation. TNT/Gr68a males were capable of discriminating the copulation status and age of target females in courtship conditioning, indicating that female discrimination and formation of olfactory courtship memory are independent of the Gr68a-expressing neurons that subserve gustation and mechanosensation. This study suggests for the first time that mechanical signals generated by a female fly have a prominent effect on males' courtship in the dark and leads the way to studying how multimodal sensory information and arousal are integrated in behavioral decision making.

  13. Do circadian genes and ambient temperature affect substrate-borne signalling during Drosophila courtship?

    Directory of Open Access Journals (Sweden)

    Izarne Medina

    2015-11-01

    Full Text Available Courtship vibratory signals can be air-borne or substrate-borne. They convey distinct and species-specific information from one individual to its prospective partner. Here, we study the substrate-borne vibratory signals generated by the abdominal quivers of the Drosophila male during courtship; these vibrations travel through the ground towards courted females and coincide with female immobility. It is not known which physical parameters of the vibrations encode the information that is received by the females and induces them to pause. We examined the intervals between each vibratory pulse, a feature that was reported to carry information for animal communication. We were unable to find evidence of periodic variations in the lengths of these intervals, as has been reported for fly acoustical signals. Because it was suggested that the genes involved in the circadian clock may also regulate shorter rhythms, we search for effects of period on the interval lengths. Males that are mutant for the period gene produced vibrations with significantly altered interpulse intervals; also, treating wild type males with constant light results in similar alterations to the interpulse intervals. Our results suggest that both the clock and light/dark cycles have input into the interpulse intervals of these vibrations. We wondered if we could alter the interpulse intervals by other means, and found that ambient temperature also had a strong effect. However, behavioural analysis suggests that only extreme ambient temperatures can affect the strong correlation between female immobility and substrate-borne vibrations.

  14. Circadian Rhythms

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 18; Issue 11. Circadian Rhythms ... M Vaze1 Vijay Kumar Sharma1. Chronobiology Laboratory Evolutionary and Organismal Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research Jakkur, PO Box 6436, Bangalore 560 064, India.

  15. Circadian Rhythms

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 2. Circadian Rhythms: Why do ... Nikhil Vijay Kumar Sharma1. Chronobiology Laboratory Evolutionary and Organismal Biology Unit Jawaharlal Nehru Centre for Advanced Scientific Research Jakkur, PO Box 6436, Bangalore 560 064, India.

  16. Circadian Rhythms

    Indian Academy of Sciences (India)

    IAS Admin

    Early studies on circadian rhythms focussed on unravelling the fundamental .... careful analysis revealed that deaths of most arrhythmic indi- viduals were due to .... is no more a sci-fi movie script and is achievable through a technique called ...

  17. Courtship herding in the fiddler crab Uca elegans.

    Science.gov (United States)

    How, Martin J; Hemmi, Jan M

    2008-12-01

    Male and female animals are not always complicit during reproduction, giving rise to coercion. One example of a system that is assumed to involve sexual coercion is the mate herding behaviour of fiddler crabs: males push females towards the home burrow with the goal of forcing copulation at the burrow entrance. We recorded and analysed in detail the courtship behaviour of a North Australian species of fiddler crab Uca elegans. Courtship was composed of four main phases: broadcast waving, outward run, herding and at burrow display. During interactions males produced claw-waving displays which were directed posteriorly towards the female and which varied in timing and structure depending on the courtship phase. We suggest that courtship herding in U. elegans is driven primarily by mate choice for the following reasons, (1) females can evade herding, (2) no other reproductive strategies were observed, (3) males broadcast their presence and accompany courtship with conspicuous claw waves, and (4) the behaviour ends with the female leading the male into the home burrow. As an alternative function for herding in U. elegans we suggest that the behaviour represents a form of courtship guiding, in which males direct complicit females to the correct home burrow.

  18. A low-cost bioprosthetic semilunar valve for research, disease modelling and surgical training applications.

    Science.gov (United States)

    Rosa, Benoit; Machaidze, Zurab; Shin, Borami; Manjila, Sunil; Brown, David W; Baird, Christopher W; Mayer, John E; Dupont, Pierre E

    2017-11-01

    This paper provides detailed instructions for constructing low-cost bioprosthetic semilunar valves for animal research and clinical training. This work fills an important gap between existing simulator training valves and clinical valves by providing fully functioning designs that can be employed in ex vivo and in vivo experiments and can also be modified to model valvular disease. Valves are constructed in 4 steps consisting of creating a metal frame, covering it with fabric and attaching a suture ring and leaflets. Computer-aided design files are provided for making the frame from wire or by metal 3D printing. The covering fabric and suturing ring are made from materials readily available in a surgical lab, while the leaflets are made from pericardium. The entire fabrication process is described in figures and in a video. To demonstrate disease modelling, design modifications are described for producing paravalvular leaks, and these valves were evaluated in porcine ex vivo (n = 3) and in vivo (n = 6) experiments. Porcine ex vivo and acute in vivo experiments demonstrate that the valves can replicate the performance of clinical valves for research and training purposes. Surgical implantation is similar, and echocardiograms are comparable to clinical valves. Furthermore, valve leaflet function was satisfactory during acute in vivo tests with little central regurgitation, while the paravalvular leak modifications consistently produced leaks in the desired locations. The detailed design procedure presented here, which includes a tutorial video and computer-aided design files, should be of substantial benefit to researchers developing valve disease models and to clinicians developing realistic valve training systems. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  19. Monoartritis gotosa de muñeca asociada a necrosis del semilunar: a propósito de un caso clínico

    OpenAIRE

    Olmedo García, N.; Mackenney Carrasco, Enrique

    1994-01-01

    Se presenta un caso de monoartritis de muñeca asociada a imágenes radiológicas de necrosis avascular del semilunar que, tras biopsia de la sinovial, se diagnostica de artritis gotosa. Esta asociación es rara. La alteración metabólica que se produce en la gota da lugar a una sinovitis, que provoca un aumento de presión intraarticular. Esta hiperpresión en el carpo podría determinar una necrosis isquémica del semilunar, pero con una evolución diferente a la enfermedad de Kienböck...

  20. Chemical cues from females trigger male courtship behaviour in grasshoppers.

    Science.gov (United States)

    Finck, Jonas; Kuntze, Janine; Ronacher, Bernhard

    2016-05-01

    Gomphocerine grasshoppers use species-specific calling songs for sex recognition and mate attraction. In two closely related species, Chorthippus biguttulus and C. mollis, acoustic communication is the only experimentally characterized communication channel that elicits male courtship behaviour. However, courtship in these species involves extensive close-range interactions that are likely to be mediated by other signalling modalities, in particular chemical cues. We developed a bioassay to determine if female cuticular hydrocarbons (CHCs) act as chemical cues that induce courtship behaviour, and if males assess variation in CHCs to determine whether or not to court a female. The results of this approach provide evidence that grasshopper males use species- and sex-specific information from CHC signals and respond with a courtship song to the CHC profile of conspecific females but not to the CHC profile of heterospecific females and conspecific males. We conclude that males of C. biguttulus and C. mollis use multimodal channels for mating decisions, based on both acoustic and olfactory cues. We discuss various factors that might favour the evolution of male choosiness in grasshoppers.

  1. Drosophila Courtship Conditioning As a Measure of Learning and Memory.

    Science.gov (United States)

    Koemans, Tom S; Oppitz, Cornelia; Donders, Rogier A T; van Bokhoven, Hans; Schenck, Annette; Keleman, Krystyna; Kramer, Jamie M

    2017-06-05

    Many insights into the molecular mechanisms underlying learning and memory have been elucidated through the use of simple behavioral assays in model organisms such as the fruit fly, Drosophila melanogaster. Drosophila is useful for understanding the basic neurobiology underlying cognitive deficits resulting from mutations in genes associated with human cognitive disorders, such as intellectual disability (ID) and autism. This work describes a methodology for testing learning and memory using a classic paradigm in Drosophila known as courtship conditioning. Male flies court females using a distinct pattern of easily recognizable behaviors. Premated females are not receptive to mating and will reject the male's copulation attempts. In response to this rejection, male flies reduce their courtship behavior. This learned reduction in courtship behavior is measured over time, serving as an indicator of learning and memory. The basic numerical output of this assay is the courtship index (CI), which is defined as the percentage of time that a male spends courting during a 10 min interval. The learning index (LI) is the relative reduction of CI in flies that have been exposed to a premated female compared to naïve flies with no previous social encounters. For the statistical comparison of LIs between genotypes, a randomization test with bootstrapping is used. To illustrate how the assay can be used to address the role of a gene relating to learning and memory, the pan-neuronal knockdown of Dihydroxyacetone phosphate acyltransferase (Dhap-at) was characterized here. The human ortholog of Dhap-at, glyceronephosphate O-acyltransferase (GNPT), is involved in rhizomelic chondrodysplasia punctata type 2, an autosomal-recessive syndrome characterized by severe ID. Using the courtship conditioning assay, it was determined that Dhap-at is required for long-term memory, but not for short-term memory. This result serves as a basis for further investigation of the underlying molecular

  2. Evidence from data storage tags for the presence of lunar and semilunar behavioral cycles in spawning Atlantic cod

    Science.gov (United States)

    Grabowski, Timothy B.; McAdam, Bruce J.; Thorsteinsson, Vilhjalmur; Marteinsdóttir, Gudrún

    2015-01-01

    Understanding the environmental processes determining the timing and success of reproduction is of critical importance to developing effective management strategies of marine fishes. Unfortunately it has proven difficult to comprehensively study the reproductive behavior of broadcast-spawning fishes. The use of electronic data storage tags (DSTs) has the potential to provide insights into the behavior of fishes. These tags allow for data collection over relatively large spatial and temporal scales that can be correlated to predicted environmental conditions and ultimately be used to refine predictions of year class strength. In this paper we present data retrieved from DSTs demonstrating that events putatively identified as Atlantic cod spawning behavior is tied to a lunar cycle with a pronounced semi-lunar cycle within it. Peak activity occurs around the full and new moon with no evidence of relationship with day/night cycles.

  3. Substrate vibrations during courtship in three Drosophila species.

    Directory of Open Access Journals (Sweden)

    Valerio Mazzoni

    Full Text Available While a plethora of studies have focused on the role of visual, chemical and near-field airborne signals in courtship of Drosophila fruit flies, the existence of substrate-borne vibrational signals has been almost completely overlooked. Here we describe substrate vibrations generated during courtship in three species of the D. melanogaster group, from the allegedly mute species D. suzukii, its sister species D. biarmipes, and from D. melanogaster. In all species, we recorded several types of substrate vibrations which were generated by locomotion, abdominal vibrations and most likely through the activity of thoracic wing muscles. In D. melanogaster and D. suzukii, all substrate vibrations described in intact males were also recorded in males with amputated wings. Evidence suggests that vibrational signalling may be widespread among Drosophila species, and fruit flies may provide an ideal model to study various aspects of this widespread form of animal communication.

  4. 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.

  5. Visible Battle Rhythm

    National Research Council Canada - National Science Library

    Cort, Brian; Bouchard, Alain; Gouin, Denis; Proulx, Pascale; Wright, William

    2006-01-01

    .... Visual Battle Rhythm (VBR) is a software prototype which updates the battle rhythm process with modern technology and careful information design to improve the synchronization, situational awareness and decision making ability of commanders...

  6. Mutation of Drosophila dopamine receptor DopR leads to male-male courtship behavior.

    Science.gov (United States)

    Chen, Bin; Liu, He; Ren, Jing; Guo, Aike

    2012-07-06

    In Drosophila, dopamine plays important roles in many biological processes as a neuromodulator. Previous studies showed that dopamine level could affect fly courtship behaviors. Disturbed dopamine level leads to abnormal courtship behavior in two different ways. Dopamine up-regulation induces male-male courtship behavior, while down-regulation of dopamine level results in increased sexual attractiveness of males towards other male flies. Until now, the identity of the dopamine receptor involved in this abnormal male-male courtship behavior remains unknown. Here we used genetic approaches to investigate the role of dopamine receptors in fly courtship behavior. We found that a dopamine D1-like receptor, DopR, was involved in fly courtship behavior. DopR mutant male flies display male-male courtship behavior. This behavior is mainly due to the male's increased propensity to court other males. Expression of functional DopR successfully rescued this mutant phenotype. Knock-down of D2-like receptor D2R and another D1-like receptor, DAMB, did not induce male-male courtship behavior, indicating the receptor-type specificity of this phenomenon. Our findings provide insight into a possible link between dopamine level disturbance and the induced male-male courtship behavior. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Female rock sparrows (Petronia petronia), not males, respond differently to simulations of different courtship interaction outcomes

    DEFF Research Database (Denmark)

    Matessi, Giuliano; Peake, Tom M.; McGregor, Peter K.

    2007-01-01

    individuals of both sexes have access to a range of mating strategies. We tested whether rock sparrows (Petronia petronia) behave differently after hearing playbacks of vocal interactions simulating a successful courtship as opposed to playback of an unsuccessful courtship. We found no support for our...

  8. Nutritional enrichment increases courtship intensity and improves mating success in male spiders

    DEFF Research Database (Denmark)

    Lomborg, Johannes Peter; Toft, Søren

    2009-01-01

    status (enriched or deficient) and that courtship intensity predicts mating success in males of the same nutritional status. We used wolf spiders, Pardosa prativaga, which have an elaborate display of courtship behaviors, including encircling, palp vibrations, abdomen vibrations, hopping, etc. Viability...

  9. Markets, Bodies, Rhythms

    DEFF Research Database (Denmark)

    Borch, Christian; Bondo Hansen, Kristian; Lange, Ann-Christina

    2015-01-01

    to respond to a widely perceived problem, namely that market rhythms might be contagious and that some form of separation of bodily and market rhythms might therefore be needed. Finally, we show how current high-frequency trading, despite being purely algorithmic, does not render the traders' bodies......This article explores the relationship between bodily rhythms and market rhythms in two distinctly different financial market configurations, namely the open-outcry pit (prevalent especially in the early 20th century) and present-day high-frequency trading. Drawing on Henri Lefebvre......'s rhythmanalysis, we show how traders seek to calibrate their bodily rhythms to those of the market. We argue that, in the case of early-20th-century open-outcry trading pits, traders tried to enact a total merger of bodily and market rhythms. We also demonstrate how, in the 1920s and '30s, market observers began...

  10. Circadian Rhythm Sleep Disorders

    Directory of Open Access Journals (Sweden)

    Erhan Akinci

    2016-06-01

    Full Text Available The circadian rhythm sleep disorders define the clinical conditions where sleep and ndash;wake rhythm is disrupted despite optimum environmental and social conditions. They occur as a result of the changes in endogenous circadian hours or non-compatibility of environmental factors or social life with endogenous circadian rhythm. The sleep and ndash;wake rhythm is disrupted continuously or in repeating phases depending on lack of balance between internal and external cycles. This condition leads to functional impairments which cause insomnia, excessive sleepiness or both in people. Application of detailed sleep anamnesis and sleep diary with actigraphy record, if possible, will be sufficient for diagnosis. The treatment aims to align endogenous circadian rhythm with environmental conditions. The purpose of this article is to review pathology, clinical characteristics, diagnosis and treatment of circadian rhythm disorder. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2016; 8(2: 178-189

  11. Through their eyes: selective attention in peahens during courtship.

    Science.gov (United States)

    Yorzinski, Jessica L; Patricelli, Gail L; Babcock, Jason S; Pearson, John M; Platt, Michael L

    2013-08-15

    Conspicuous, multicomponent ornamentation in male animals can be favored by female mate choice but we know little about the cognitive processes females use to evaluate these traits. Sexual selection may favor attention mechanisms allowing the choosing females to selectively and efficiently acquire relevant information from complex male display traits and, in turn, may favor male display traits that effectively capture and hold female attention. Using a miniaturized telemetric gaze-tracker, we show that peahens (Pavo cristatus) selectively attend to specific components of peacock courtship displays and virtually ignore other, highly conspicuous components. Females gazed at the lower train but largely ignored the head, crest and upper train. When the lower train was obscured, however, females spent more time gazing at the upper train and approached the upper train from a distance. Our results suggest that peahens mainly evaluate the lower train during close-up courtship but use the upper train as a long-distance attraction signal. Furthermore, we found that behavioral display components (train rattling and wing shaking) captured and maintained female attention, indicating that interactions between display components may promote the evolution of multicomponent displays. Taken together, these findings suggest that selective attention plays a crucial role in sexual selection and likely influences the evolution of male display traits.

  12. Physiological Costs of Repetitive Courtship Displays in Cockroaches Handicap Locomotor Performance

    Science.gov (United States)

    Mowles, Sophie L.; Jepson, Natalie M.

    2015-01-01

    Courtship displays are typically thought to have evolved via female choice, whereby females select mates based on the characteristics of a display that is expected to honestly reflect some aspect of the male’s quality. Honesty is typically enforced by mechanistic costs and constraints that limit the level at which a display can be performed. It is becoming increasingly apparent that these costs may be energetic costs involved in the production of dynamic, often repetitive displays. A female attending to such a display may thus be assessing the physical fitness of a male as an index of his quality. Such assessment would provide information on his current physical quality as well as his ability to carry out other demanding activities, qualities with which a choosy female should want to provision her offspring. In the current study we use courtship interactions in the Cuban burrowing cockroach, Byrsotria fumigata to directly test whether courtship is associated with a signaler’s performance capacity. Males that had produced courtship displays achieved significantly lower speeds and distances in locomotor trials than non-courting control males. We also found that females mated more readily with males that produced a more vigorous display. Thus, males of this species have developed a strategy where they produce a demanding courtship display, while females choose males based on their ability to produce this display. Courtship displays in many taxa often involve dynamic repetitive actions and as such, signals of stamina in courtship may be more widespread than previously thought. PMID:26606147

  13. Frequent misdirected courtship in a natural community of colorful Habronattus jumping spiders.

    Science.gov (United States)

    Taylor, Lisa A; Powell, Erin C; McGraw, Kevin J

    2017-01-01

    Male courtship display is common in many animals; in some cases, males engage in courtship indiscriminately, spending significant time and energy courting heterospecifics with whom they have no chance of mating or producing viable offspring. Due to high costs and few if any benefits, we might expect mechanisms to evolve to reduce such misdirected courtship (or 'reproductive interference'). In Habronattus jumping spiders, males frequently court heterospecifics with whom they do not mate or hybridize; females are larger and are voracious predators, posing a severe risk to males who court indiscriminately. In this study, we examined patterns of misdirected courtship in a natural community of four sympatric Habronattus species (H. clypeatus, H. hallani, H. hirsutus, and H. pyrrithrix). We used direct field observations to weigh support for two hypotheses (differential microhabitat use and species recognition signaling) to explain how these species reduce the costs associated with misdirected courtship. We show that, while the four species of Habronattus do show some differences in microhabitat use, all four species still overlap substantially, and in three of the four species individuals equally encountered heterospecifics and conspecifics. Males courted females at every opportunity, regardless of species, and in some cases, this led to aggression and predation by the female. These results suggest that, while differences in microhabitat use might reduce misdirected courtship to some extent, co-existence of these four species may be possible due to complex communication (i.e. species-specific elements of a male's courtship display). This study is the first to examine misdirected courtship in jumping spiders. Studies of misdirected courtship and its consequences in the field are limited and may broaden our understanding of how biodiversity is maintained within a community.

  14. Moths are not silent, but whisper ultrasonic courtship songs

    DEFF Research Database (Denmark)

    Nakano, R; Takanashi, T; Fujii, T

    2009-01-01

    ) were recently shown to whisper extremely low-intensity ultrasonic courtship songs close to females. Since low sound levels will prevent eavesdropping by predators, parasites and conspecific rivals, we predicted low intensity ultrasound communication to be widespread among moths. Here we tested 13...... species of moths including members of the Noctuidae, Arctiidae, Geometridae and Crambidae. Males of nine species, 70%, produced broadband ultrasound close to females. Peak frequencies ranged from 38 to above 100 kHz. All sounds were of low intensity, 43-76 dB SPL at 1 cm [64+/-10 dB peSPL (mean +/- s......Ultrasonic hearing is widespread among moths, but very few moth species have been reported to produce ultrasounds for sexual communication. In those that do, the signals are intense and thus well matched for long distance communication. By contrast, males of the Asian corn borer moth (Crambidae...

  15. Avaliação artroscópica e macroscópica da faceta medial do semilunar Arthroscopic and macroscopic evaluation of the lunate medial facet

    Directory of Open Access Journals (Sweden)

    Edgard de Novaes França Bisneto

    2011-01-01

    Full Text Available OBJETIVO: avaliar a correlação entre a presença de uma faceta medial do semilunar e a incidência de lesões ligamentares e artrose do pólo proximal do hamato. MÉTODOS: Avaliação artroscópica e dissecação dos punhos foram efetuados em cadáveres. RESULTADOS: Houve uma correlação clara, estatisticamente significativa entre artrose do pólo proximal do hamato e a presença da faceta medial do semilunar. CONCLUSÃO: Artrose do pólo proximal do hamato está correlacionada com a presença do tipo II semilunar. Nível de Evidência III, Estudo de pacientes nãoconsecutivos; sem padrão de referência "ouro" aplicado uniformementeOBJECTIVE: To evaluate the correlation between the presence of a lunate medial facet and the incidence of ligament lesions of the wrist and arthrosis of the proximal pole of the hamate. This study was carried out on cadavers. METHODS: Arthroscopic evaluation and dissection were performed on cadaver wrists. RESULTS: There was a clear, statistically significant correlation between arthrosis of the proximal pole of the hamate and the presence of a medial facet on the lunate. CONCLUSION: Arthrosis of the proximal pole of the hamate is correlated with the presence of a type II lunate. Level of Evidence III, Study of nonconsecutive patients; without consistently applied reference ''gold'' standard.

  16. Rhythm in language acquisition.

    Science.gov (United States)

    Langus, Alan; Mehler, Jacques; Nespor, Marina

    2017-10-01

    Spoken language is governed by rhythm. Linguistic rhythm is hierarchical and the rhythmic hierarchy partially mimics the prosodic as well as the morpho-syntactic hierarchy of spoken language. It can thus provide learners with cues about the structure of the language they are acquiring. We identify three universal levels of linguistic rhythm - the segmental level, the level of the metrical feet and the phonological phrase level - and discuss why primary lexical stress is not rhythmic. We survey experimental evidence on rhythm perception in young infants and native speakers of various languages to determine the properties of linguistic rhythm that are present at birth, those that mature during the first year of life and those that are shaped by the linguistic environment of language learners. We conclude with a discussion of the major gaps in current knowledge on linguistic rhythm and highlight areas of interest for future research that are most likely to yield significant insights into the nature, the perception, and the usefulness of linguistic rhythm. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Courtship pheromones in parasitic wasps: comparison of bioactive and inactive hydrocarbon profiles by multivariate statistical methods

    NARCIS (Netherlands)

    Steiner, S.; Mumm, R.; Ruther, J.

    2007-01-01

    Cuticular hydrocarbons play a significant role in the regulation of cuticular permeability and also in the chemical communication of insects. In the parasitoid Lariophagus distinguendus (Hymenoptera: Pteromalidae), male courtship behavior is mediated by a female-produced sex pheromone. Previous

  18. The impact of men's magazines on adolescent boys' objectification and courtship beliefs.

    Science.gov (United States)

    Ward, L Monique; Vandenbosch, Laura; Eggermont, Steven

    2015-02-01

    Although much attention concerning the potential impact of sexualized media has focused on girls and women, less is known about how this content effects boys' perceptions of women and courtship. Accordingly, the current three-wave panel study investigated whether exposure to sexualizing magazines predicts adolescent boys' (N = 592) sexually objectifying notions of women and their beliefs about feminine courtship strategies. The results indicated that when boys consumed sexualizing magazines more often, they expressed more gender-stereotypical beliefs about feminine courtship strategies over time. This association was mediated by boys' objectification of women. The possibility of a reciprocal relation whereby beliefs about courtship strategies predict future consumption of sexualizing magazines was also explored but received no support. Discussion focuses on effects of sexualizing media on boys, and supports future research to build on multidisciplinary knowledge. Copyright © 2014 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  19. Phase-Specific Vocalizations of Male Mice at the Initial Encounter during the Courtship Sequence.

    Directory of Open Access Journals (Sweden)

    Yui K Matsumoto

    Full Text Available Mice produce ultrasonic vocalizations featuring a variety of syllables. Vocalizations are observed during social interactions. In particular, males produce numerous syllables during courtship. Previous studies have shown that vocalizations change according to sexual behavior, suggesting that males vary their vocalizations depending on the phase of the courtship sequence. To examine this process, we recorded large sets of mouse vocalizations during male-female interactions and acoustically categorized these sounds into 12 vocal types. We found that males emitted predominantly short syllables during the first minute of interaction, more long syllables in the later phases, and mainly harmonic sounds during mounting. These context- and time-dependent changes in vocalization indicate that vocal communication during courtship in mice consists of at least three stages and imply that each vocalization type has a specific role in a phase of the courtship sequence. Our findings suggest that recording for a sufficiently long time and taking the phase of courtship into consideration could provide more insights into the role of vocalization in mouse courtship behavior in future study.

  20. Courtship Pheromone Use in a Model Urodele, the Mexican Axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Maex, Margo; Van Bocxlaer, Ines; Mortier, Anneleen; Proost, Paul; Bossuyt, Franky

    2016-02-04

    Sex pheromones have been shown to constitute a crucial aspect of salamander reproduction. Until now, courtship pheromones of Salamandridae and Plethodontidae have been intensively studied, but information on chemical communication in other urodelan families is essentially lacking. The axolotl (Ambystoma mexicanum, Ambystomatidae) has a courtship display that suggests a key role for chemical communication in the orchestration of its sexual behavior, but no sex pheromones have yet been characterized from this species. Here we combined whole transcriptome analyses of the male cloaca with proteomic analyses of water in which axolotls were allowed to court to show that male axolotls secrete multiple ca. 20 kDa glycosylated sodefrin precursor-like factor (SPF) proteins during courtship. In combination with phylogenetic analyses, our data show that the male cloaca essentially secretes a courtship-specific clade of SPF proteins that is orthologous to salamandrid courtship pheromones. In addition, we identified an SPF protein for which no orthologs have been described from other salamanders so far. Overall, our study advocates a central role for SPF proteins during the courtship display of axolotls and adds knowledge on pheromone use in a previously unexplored deep evolutionary branch of salamander evolution.

  1. External and internal controls of lunar-related reproductive rhythms in fishes.

    Science.gov (United States)

    Takemura, A; Rahman, M S; Park, Y J

    2010-01-01

    Reproductive activities of many fish species are, to some extent, entrained to cues from the moon. During the spawning season, synchronous spawning is repeated at intervals of c. 1 month (lunar spawning cycle) and 2 weeks (semi-lunar spawning cycle) or daily according to tidal changes (tidal spawning cycle). In species showing lunar-related spawning cycles, oocytes in the ovary develop towards and mature around a specific moon phase for lunar spawners, around spring tides for semi-lunar spawners and at daytime high tides for tidal spawners. The production of sex steroid hormones also changes in accordance with synchronous oocyte development. Since the production of the steroid hormones with lunar-related reproductive periodicity is regulated by gonadotropins, it is considered that the higher parts of the hypothalamus-pituitary-gonad axis play important roles in the perception and regulation of lunar-related periodicity. It is likely that fishes perceive cues from the moon by sensory organs; however, it is still unknown how lunar cues are transduced as an endogenous rhythm exerting lunar-related spawning rhythmicity. Recent research has revealed that melatonin fluctuated according to the brightness at night, magnetic fields and the tidal cycle. In addition, cyclic changes in hydrostatic pressure had an effect on monoamine contents in the brain. These factors may be indirectly related to the exertion of lunar-related periodicity. Molecular approaches have revealed that mRNA expressions of light-sensitive clock genes change with moonlight, suggesting that brightness at night plays a role in phase-shifting or resetting of biological clocks. Some species may have evolved biological clocks in relation to lunar cycles, although it is still not known how lunar periodicities are endogenously regulated in fishes. This review demonstrates that lunar-related periodicity is utilized and incorporated by ecological and physiological mechanisms governing the reproductive success

  2. Short and fast vs long and slow: age changes courtship in male orb-web spiders ( Argiope keyserlingi)

    Science.gov (United States)

    O'Hanlon, James C.; Wignall, Anne E.; Herberstein, Marie E.

    2018-02-01

    Male reproductive performance can vary with condition, age and future reproductive opportunities. Web-building spiders are ideal models to examine the effects of senescence on fitness-related behaviours due to strong selection on male courtship to reduce pre-copulatory sexual cannibalism. Argiope keyserlingi spiders generate courtship vibrations, or `shudders', that reduce female aggression. We found that male A. keyserlingi courtship slowed with chronological age. Older males took longer to travel across the courtship thread, and overall number of shudders increased. Males retained some ability to modulate courtship quality (shudder duration and number of rocks within each shudder) in response to female quality. A change in courtship performance over time, despite strong selection for repeatability, indicates that ageing in male A. keyserlingi may have direct impacts on reproductive performance.

  3. Courtship, sex and poverty: illegitimacy in eighteenth-century Wales.

    Science.gov (United States)

    Muir, Angela Joy

    2018-01-01

    This article sheds new light on illegitimacy in eighteenth-century Britain through an analysis of evidence from 36 parishes across the former Welsh counties Montgomeryshire and Radnorshire. Quantitative analysis of illegitimacy ratios demonstrates that levels were significantly higher in certain, but not all, parts of Wales in the eighteenth century. This evidence is considered in relation to explanatory frameworks used in the analysis of English data, which attempt to account for rising levels through cultural changes that influenced premarital sexual behaviour, and economic opportunities created by industrialization. Welsh evidence appears to present a challenge to these understandings in two key ways: Wales was linguistically different and lacked certain cultural markers which some historians have associated with an eighteenth-century 'sexual revolution', and because the highest levels of illegitimacy were found in agricultural regions of Wales which experienced little or no industrial change. It is argued that Welsh illegitimacy was influenced by a combination of courtship-led marriage customs, a decline in traditional forms of social control and worsening economic circumstances which, on closer examination, appear remarkably similar to London. This analysis provides further evidence that illegitimacy in eighteenth-century Britain was a deeply complex phenomenon governed by diverse regionally specific social and economic influences.

  4. Periodic regulation of expression of genes for kisspeptin, gonadotropin-inhibitory hormone and their receptors in the grass puffer: Implications in seasonal, daily and lunar rhythms of reproduction.

    Science.gov (United States)

    Ando, Hironori; Shahjahan, Md; Kitahashi, Takashi

    2018-04-03

    The seasonal, daily and lunar control of reproduction involves photoperiodic, circadian and lunar changes in the activity of kisspeptin, gonadotropin-inhibitory hormone (GnIH) and gonadotropin-releasing hormone (GnRH) neurons. These changes are brought through complex networks of light-, time- and non-photic signal-dependent control mechanisms, which are mostly unknown at present. The grass puffer, Takifugu alboplumbeus, a semilunar spawner, provides a unique and excellent animal model to assess this question because its spawning is synchronized with seasonal, daily and lunar cycles. In the diencephalon, the genes for kisspeptin, GnIH and their receptors showed similar expression patterns with clear seasonal and daily oscillations, suggesting that they are regulated by common mechanisms involving melatonin, circadian clock and water temperature. For implications in semilunar-synchronized spawning rhythm, melatonin receptor genes showed ultradian oscillations in expression with the period of 14.0-15.4 h in the pineal gland. This unique ultradian rhythm might be driven by circatidal clock. The possible circatidal clock and circadian clock in the pineal gland may cooperate to drive circasemilunar rhythm to regulate the expression of the kisspeptin, GnIH and their receptor genes. On the other hand, high temperature (over 28 °C) conditions, under which the expression of the kisspeptin and its receptor genes is markedly suppressed, may provide an environmental signal that terminates reproduction at the end of breeding period. Taken together, the periodic regulation of the kisspeptin, GnIH and their receptor genes by melatonin, circadian clock and water temperature may be important in the precisely-timed spawning of the grass puffer. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. RHYTHM STRUCTURE IN NEWS READING

    Directory of Open Access Journals (Sweden)

    Lluís Mas Manchón

    2013-06-01

    Full Text Available Rhythm is central to news reading in radio and television programs. This paper proposes a three level structure for rhythm in news discourse. It gives a comprehensive definition of rhythm and types of rhythm. Firstly, the Base Rhythm Structure consists of semantic and pragmatic rhythmic accents, coincident with very specific words. Secondly, these accents are grouped together according to type, frequency and order, thereby configuring three types of “rhythmic units” (the Internal Rhythm Structure: starting, main and end units. A last structure level presents four discursive factors that are very important in integrating the overall time structure of news announcing (the Melodic Rhythm Structure. This integral structure for news announcing rhythm should be further tested in acoustic-experimental studies under the criterion of information transmission efficacy.

  6. Light Rhythms in Architecture

    DEFF Research Database (Denmark)

    Bülow, Katja

    2013-01-01

    formation and rhythm. When integrated into an architectural concept, electrical lighting non-intended for poetic composition has the ability to contribute to place, time, and function-telling aspects of places in urban contexts. Urban environments are information wise challenging to pre-historic human...

  7. Biological Clocks & Circadian Rhythms

    Science.gov (United States)

    Robertson, Laura; Jones, M. Gail

    2009-01-01

    The study of biological clocks and circadian rhythms is an excellent way to address the inquiry strand in the National Science Education Standards (NSES) (NRC 1996). Students can study these everyday phenomena by designing experiments, gathering and analyzing data, and generating new experiments. As students explore biological clocks and circadian…

  8. Circadian Rhythms in Cyanobacteria

    Science.gov (United States)

    Golden, Susan S.

    2015-01-01

    SUMMARY Life on earth is subject to daily and predictable fluctuations in light intensity, temperature, and humidity created by rotation of the earth. Circadian rhythms, generated by a circadian clock, control temporal programs of cellular physiology to facilitate adaptation to daily environmental changes. Circadian rhythms are nearly ubiquitous and are found in both prokaryotic and eukaryotic organisms. Here we introduce the molecular mechanism of the circadian clock in the model cyanobacterium Synechococcus elongatus PCC 7942. We review the current understanding of the cyanobacterial clock, emphasizing recent work that has generated a more comprehensive understanding of how the circadian oscillator becomes synchronized with the external environment and how information from the oscillator is transmitted to generate rhythms of biological activity. These results have changed how we think about the clock, shifting away from a linear model to one in which the clock is viewed as an interactive network of multifunctional components that are integrated into the context of the cell in order to pace and reset the oscillator. We conclude with a discussion of how this basic timekeeping mechanism differs in other cyanobacterial species and how information gleaned from work in cyanobacteria can be translated to understanding rhythmic phenomena in other prokaryotic systems. PMID:26335718

  9. RHYTHM DISTURBANCES DURING COLONOSCOPY

    Directory of Open Access Journals (Sweden)

    D. Jordanov

    2012-08-01

    Full Text Available Purpose: The purpose of this study is to assess the risk of inducing rhythm disturbances of the heart during colonoscopy.Patients and methods used: 80 patients had undergone colonoscopyper formed by two experienced specialists of endoscopy for the period from March to December 2011. The endoscopies were performed without premedication and sedation. Holter was placed on each patient one hour before the endoscopic examination, and the record continued one hour after the manipulation. The blood pressure was measured before, during and after the procedure.Results: During colonoscopy 25 patients (31,25% manifested rhythm disorders. In 15 patients (18,75% sinus tachycardia occurred. In 7 patients (8,75% suptraventricular extra systoles were observed and in 3 patients (3,75% - ventricular extra systoles. No ST-T changes were found. Highest values of the blood pressure were measured before and during the endoscopy, but the values did not exceed 160/105 mmHg. In 10 patients (12,5% a hypotensive reaction was observed, bur the values were not lower than 80/ 50. In 2 patients there was a short bradycardia with a heart frequency 50-55 /min.Conclusions: Our results showed that the rhythm disorders during lower colonoscopy occur in approximately 1/3 of the examined patients, there is an increase or decrease of the blood pressure in some patients, but that doesn’t require physician’s aid and the examination can be carried out safely without monitoring.

  10. Courtship displays of introgressed, interspecific hybrid Nasonia males : Further investigations into the 'grandfather effect'

    NARCIS (Netherlands)

    Beukeboom, L.W.; Assem, J. van den

    Previously, we investigated courtship behaviour of bidirectional, interspecific hybrid males of two species of Nasonia (Beukeboom & van den Assem, 2001). Characteristics of the displays were intermediate between those of the parental species, but at the same time were biased towards the paternal

  11. Do male birds intercept and use rival courtship calls to adjust paternity protection behaviours?

    DEFF Research Database (Denmark)

    Matessi, Giuliano; McGregor, Peter Kenneth; Peake, Thomas More

    2005-01-01

    Abstract: We tested whether male rock sparrows (Petronia petronia) change behaviours directed at their females when played back courtship display calls simulating a potential cuckolding event in the vicinity of their nests. We compared the behaviour of males before, during and after such playback...... and communication strategies, and extend our knowledge of how the social environment can affect within-pair dynamics....

  12. Conventions of Courtship: Gender and Race Differences in the Significance of Dating Rituals

    Science.gov (United States)

    Jackson, Pamela Braboy; Kleiner, Sibyl; Geist, Claudia; Cebulko, Kara

    2011-01-01

    Dating rituals include dating--courtship methods that are regularly enacted. This study explores gender and race differences in the relative importance placed on certain symbolic activities previously identified by the dating literature as constituting such rituals. Using information collected from a racially diverse sample of college students (N…

  13. Serotonergic activation during courtship and aggression in the brown anole, Anolis sagrei

    Directory of Open Access Journals (Sweden)

    Jacob T. Hartline

    2017-05-01

    Full Text Available The role of serotonin (5-hydroxytryptamine, 5-HT in social behavior regulation is not fully understood. While 5-HT release in nuclei of the social behavior network has generally been associated with inhibition of aggressive behavior across multiple classes of vertebrates, less is known about its effects on sexual, especially non-copulatory courtship display behaviors. Furthermore, most research has examined effects at 5-HT release sites, while studies examining the behavioral relevance of source cell populations have generated contradictory findings. This study utilized immunohistochemistry to examine the colocalization of 5-HT with Fos, an immediate early gene product and marker of neural activity, in the raphe and superior reticular nuclei of male brown anoles (Anolis sagrei exposed to either aggression, courtship, or control social interactions. Supporting previous research, copulation was associated with a decrease in 5-HT activity, while a novel link between 5-HT activity and latency to non-copulatory courtship was also found. Within the aggression group, intensity and frequency of behavior were both associated with decreased 5-HT activity. An effect of social context was also seen, with anoles exposed to either courtship or aggression encounters showing decreased 5-HT activity in certain raphe and superior reticular nuclei populations compared to controls. Interestingly, context effects and behavioral effects were seen at separate brain nuclei, suggesting the presence of separate systems with distinct functional roles.

  14. Courtship behavior of different wild strains of Ceratitis Capitata (Diptera: Tephritidae)

    International Nuclear Information System (INIS)

    Briceno, D.; Eberhard, W.; Vilardi, J.; Cayol, J.-P.; Shelly, T.

    2007-01-01

    This study documents differences in the courtship behavior of wild strains of Ceratitis capitata (Wiedemann) from Madeira (Portugal), Hawaii (U.S.A.), Costa Rica, and Patagonia (Argentina). Some traits showed large variations and others substantial overlaps. The angle at which the male faced toward the female at the moment of transition from continuous wing vibration and intermittent buzzing changed very little during the course of courtship in all strains, but males from Madeira tended to face more directly toward the female than other males. Females tended to look more, and more directly, toward the males as courtship progressed in all strains. The distance between male and female tended to decrease as courtship proceeded in all strains, but the distances at which males initiated continuous vibration, intermittent buzzing, and jumped onto the female were relatively less variable between strains, except for the strain from Costa Rica. Flies of Madeira courted for longer and the male moved his head and buzzed his wings longer than the other strains. (author) [es

  15. Do male birds intercept and use rival courtship calls to adjust paternity protection behaviours?

    DEFF Research Database (Denmark)

    Matessi, Giuliano; McGregor, Peter Kenneth; Peake, Thomas More

    2005-01-01

    Abstract: We tested whether male rock sparrows (Petronia petronia) change behaviours directed at their females when played back courtship display calls simulating a potential cuckolding event in the vicinity of their nests. We compared the behaviour of males before, during and after such playback...

  16. Sexually dimorphic activation of dopaminergic areas depends on affiliation during courtship and pair formation

    Directory of Open Access Journals (Sweden)

    Mai eIwasaki

    2014-06-01

    Full Text Available For many species, dyadic interaction during courtship and pair bonding engage intense emotional states that control approach or avoidance behavior. Previous studies have shown that one component of a common social brain network (SBN, dopaminergic areas, are highly engaged during male songbird courtship of females. We tested whether the level of activity in dopaminergic systems of both females and males during courtship is related to their level of affiliation. In order to objectively quantify affiliative behaviors, we developed a system for tracking the position of both birds during free interaction sessions. During a third successive daily interaction session, there was a range of levels of affiliation among bird pairs, as quantified by several position and movement parameters. Because both positive and negative social interactions were present, we chose to characterize affiliation strength by pair valence. As a potential neural system involved in regulating pair valence, the level of activity of the dopaminergic group A11 (within the central gray was selectively reduced in females of positive valence pairs. Further, activation of non-dopaminergic neurons in VTA was negatively related to valence, with this relationship strongest in ventral VTA of females. Together, these results suggest that inhibition of fear or avoidance networks may be associated with development of close affiliation, and highlight the importance of negative as well as positive emotional states in the process of courtship, and in development of long-lasting social bonds.

  17. Experimental tests of light-pollution impacts on nocturnal insect courtship and dispersal.

    Science.gov (United States)

    Firebaugh, Ariel; Haynes, Kyle J

    2016-12-01

    Though a number of effects of artificial light pollution on behavior and physiology have been described, there is little understanding of their consequences for the growth and distribution of populations. Here, we document impacts of light pollution on aspects of firefly population ecology and underlying mating behaviors. Many firefly species have a unique communication system whereby bioluminescent flashes are used in courtship displays to find and attract mates. We performed a series of manipulative field experiments in which we quantified the effects of adding artificial nighttime lighting on abundances and total flashing activity of fireflies, courtship behaviors and mating between tethered females and free-flying males, and dispersal distances of marked individuals. We show that light pollution reduces flashing activities in a dark-active firefly species (Photuris versicolor) by 69.69 % and courtship behavior and mating success in a twilight-active species (Photinus pyralis). Though courtship behavior and mating success of Photinus pyralis was reduced by light pollution, we found no effects of light pollution on male dispersal in this species. Our findings suggest that light pollution is likely to adversely impact firefly populations, and contribute to wider discussions about the ecological consequences of sensory pollution.

  18. Light Rhythms in Architecture

    DEFF Research Database (Denmark)

    Bülow, Katja

    2013-01-01

    On one hand, urban lighting expresses itself in a complex visual environment made by the interplay by between many separate lighting schemes, as street lighting, shop lighting, luminous commercials etc. On the other, a noticeable order of patterns occurs, when lighting is observed as luminous...... formation and rhythm. When integrated into an architectural concept, electrical lighting non-intended for poetic composition has the ability to contribute to place, time, and function-telling aspects of places in urban contexts. Urban environments are information wise challenging to pre-historic human...... instincts, but they can be met by careful selection and adjustment of existing light situations....

  19. Orchestrating intensities and rhythms

    DEFF Research Database (Denmark)

    Staunæs, Dorthe; Juelskjær, Malou

    2016-01-01

    environmentality and learning-centered governance standards has dramatic and performative effects for the production of (educational) subjectivities. This implies a shift from governing identities, categories and structures towards orchestrating affective intensities and rhythms. Finally, the article discusses...... and the making of subjects have held sway for many years; and it is also well known that schools have been some of the most regular purchasers of psychological methods, tests and classifications. Following but also elaborating upon governmentality studies, it is suggested that a current shift towards...

  20. Sleep, Memory & Brain Rhythms.

    Science.gov (United States)

    Watson, Brendon O; Buzsáki, György

    2015-01-01

    Sleep occupies roughly one-third of our lives, yet the scientific community is still not entirely clear on its purpose or function. Existing data point most strongly to its role in memory and homeostasis: that sleep helps maintain basic brain functioning via a homeostatic mechanism that loosens connections between overworked synapses, and that sleep helps consolidate and re-form important memories. In this review, we will summarize these theories, but also focus on substantial new information regarding the relation of electrical brain rhythms to sleep. In particular, while REM sleep may contribute to the homeostatic weakening of overactive synapses, a prominent and transient oscillatory rhythm called "sharp-wave ripple" seems to allow for consolidation of behaviorally relevant memories across many structures of the brain. We propose that a theory of sleep involving the division of labor between two states of sleep-REM and non-REM, the latter of which has an abundance of ripple electrical activity-might allow for a fusion of the two main sleep theories. This theory then postulates that sleep performs a combination of consolidation and homeostasis that promotes optimal knowledge retention as well as optimal waking brain function.

  1. Circadian rhythms regulate amelogenesis.

    Science.gov (United States)

    Zheng, Li; Seon, Yoon Ji; Mourão, Marcio A; Schnell, Santiago; Kim, Doohak; Harada, Hidemitsu; Papagerakis, Silvana; Papagerakis, Petros

    2013-07-01

    Ameloblasts, the cells responsible for making enamel, modify their morphological features in response to specialized functions necessary for synchronized ameloblast differentiation and enamel formation. Secretory and maturation ameloblasts are characterized by the expression of stage-specific genes which follows strictly controlled repetitive patterns. Circadian rhythms are recognized as key regulators of the development and diseases of many tissues including bone. Our aim was to gain novel insights on the role of clock genes in enamel formation and to explore the potential links between circadian rhythms and amelogenesis. Our data shows definitive evidence that the main clock genes (Bmal1, Clock, Per1 and Per2) oscillate in ameloblasts at regular circadian (24 h) intervals both at RNA and protein levels. This study also reveals that the two markers of ameloblast differentiation i.e. amelogenin (Amelx; a marker of secretory stage ameloblasts) and kallikrein-related peptidase 4 (Klk4, a marker of maturation stage ameloblasts) are downstream targets of clock genes. Both, Amelx and Klk4 show 24h oscillatory expression patterns and their expression levels are up-regulated after Bmal1 over-expression in HAT-7 ameloblast cells. Taken together, these data suggest that both the secretory and the maturation stages of amelogenesis might be under circadian control. Changes in clock gene expression patterns might result in significant alterations of enamel apposition and mineralization. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. The Rhetorical Nature of Rhythm

    NARCIS (Netherlands)

    Balint, Mihaela; Dascalu, Mihai; Trausan-Matu, Stefan

    2017-01-01

    Up to date, linguistic rhythm has been studied for speech, but the rhythm of written texts has been merely recognized, and not analyzed or interpreted in connection to natural language tasks. We provide an extension of the textual rhythmic features we proposed in previous work, and

  3. Sex-specific signaling in the blood-brain barrier is required for male courtship in Drosophila.

    Directory of Open Access Journals (Sweden)

    Valbona Hoxha

    Full Text Available Soluble circulating proteins play an important role in the regulation of mating behavior in Drosophila melanogaster. However, how these factors signal through the blood-brain barrier (bbb to interact with the sex-specific brain circuits that control courtship is unknown. Here we show that male identity of the blood-brain barrier is necessary and that male-specific factors in the bbb are physiologically required for normal male courtship behavior. Feminization of the bbb of adult males significantly reduces male courtship. We show that the bbb-specific G-protein coupled receptor moody and bbb-specific Go signaling in adult males are necessary for normal courtship. These data identify sex-specific factors and signaling processes in the bbb as important regulators of male mating behavior.

  4. Patterns of resistance and transgression in Eastern Indonesia: single women's practices of clandestine courtship and cohabitation.

    Science.gov (United States)

    Bennett, Linda Rae

    2005-03-01

    This paper explores how single women in the regional Indonesian city of Mataram express sexual desire in a social, cultural and political climate that idealizes the confinement of female sexuality within marriage. It is based on 21 months of ethnographic fieldwork conducted with single women, their families and health care providers. Success for young women in negotiating sexual desire is dependent upon their ability to maintain a faultless public reputation and mediate between their desires and those of men. Many single women find ways to pursue their desires by bending the rules of courtship conventions, performing sexual purity in public, while resisting from within the hegemonic sexual culture. However, women who visibly transgress dominant sexual ideals (and in doing so offend the status quo) are stigmatized and ostracized. Single women's practice of resistance and sexual transgression in premarital relationships are represented using the examples of pacaran backstreet (clandestine courtship) and cohabitation prior to marriage.

  5. Endocrine disruption of courtship behaviour and reproduction in zebrafish (Danio rerio)

    DEFF Research Database (Denmark)

    Broch-Lips, Mia Gina Gruwier

    2011-01-01

    of the reversibility of hormonally induced shifts in sex ratio of zebrafish. In the first part of this study zebrafish were exposed to three different environmentally relevant concentrations of the synthetic oestrogen17α-ethinylestradiol (EE2) from egg stage to sexual maturity. Secondary sexual characteristics...... as fertilizing the spawned eggs. It was further demonstrated that the exposure to TB led to irreversible masculinisation of zebrafish which is in contrast with the partial reversibility of oestrogen induced sex change. During my investigations leading to this thesis it became apparent that sexual behaviour...... courtship behaviour have only been scarcely investigated. The aim of this project was to learn more about the effects of EDCS on the courtship behaviour and reproduction in zebrafish as well as investigating the reversibility of observed effects. I furthermore observed some interesting aspects...

  6. An endocrine disrupting chemical changes courtship and parental care in the sand goby

    International Nuclear Information System (INIS)

    Saaristo, Minna; Craft, John A.; Lehtonen, Kari K.; Lindstroem, Kai

    2010-01-01

    Endocrine disrupting chemicals (EDCs) are a diverse group of compounds that can mimic, block or modulate the synthesis of natural hormones. They are known to cause impairment of reproduction of aquatic organisms at very low concentrations. The aim of this study was to examine how exposure from 10 to 31 days to 17α-ethinyl estradiol (EE2, 41 ng L -1 ) affects the courtship and parental care behaviour of male sand gobies (Pomatoschistus minutus). The sand goby exhibits a polygynous mating system, where males compete for females and provide paternal care. First, male courtship performance towards a stimulus female was recorded with video camera. Secondly, after the male had received eggs his parental care behaviour was video recorded. In addition to behavioural endpoints, we measured the expression of hepatic vitellogenin (Vtg) and zona radiata protein (Zrp) mRNA, as well as common somatic indices. Our study shows that exposure to EE2 affected male fanning behaviour during both courtship and parental care. Interestingly, small exposed males increased their courtship fanning to similar levels as larger control males. However, during parental care egg fanning was not related to male size, and all exposed males fanned more than control males. The EE2-exposure induced Vtg and Zrp mRNA expression in males and decreased hepatosomatic index (HSI), and increased gonadosomatic index (GSI). Females prefer males that fan more, which will favour the small EDC exposed males. This may lead to mating that favours males that are not strong enough to tend the eggs until they hatch, thus decreasing the reproductive success of individuals.

  7. An endocrine disrupting chemical changes courtship and parental care in the sand goby

    Energy Technology Data Exchange (ETDEWEB)

    Saaristo, Minna, E-mail: Minna.Saaristo@helsinki.fi [Department of Bio- and Environmental Sciences, University of Helsinki, P.O. Box 65, FI-00014 Helsinki (Finland); Craft, John A. [Biological and Biomedical Sciences, Glasgow Caledonian University, Cowcaddens Road, Glasgow G4 0BA, Scotland (United Kingdom); Lehtonen, Kari K. [Finnish Environment Institute, Marine Research Centre, P.O. Box 140, FI-00251 Helsinki (Finland); Lindstroem, Kai [Environmental and Marine Biology, Abo Akademi University, FI-20520 Turku (Finland)

    2010-05-10

    Endocrine disrupting chemicals (EDCs) are a diverse group of compounds that can mimic, block or modulate the synthesis of natural hormones. They are known to cause impairment of reproduction of aquatic organisms at very low concentrations. The aim of this study was to examine how exposure from 10 to 31 days to 17{alpha}-ethinyl estradiol (EE2, 41 ng L{sup -1}) affects the courtship and parental care behaviour of male sand gobies (Pomatoschistus minutus). The sand goby exhibits a polygynous mating system, where males compete for females and provide paternal care. First, male courtship performance towards a stimulus female was recorded with video camera. Secondly, after the male had received eggs his parental care behaviour was video recorded. In addition to behavioural endpoints, we measured the expression of hepatic vitellogenin (Vtg) and zona radiata protein (Zrp) mRNA, as well as common somatic indices. Our study shows that exposure to EE2 affected male fanning behaviour during both courtship and parental care. Interestingly, small exposed males increased their courtship fanning to similar levels as larger control males. However, during parental care egg fanning was not related to male size, and all exposed males fanned more than control males. The EE2-exposure induced Vtg and Zrp mRNA expression in males and decreased hepatosomatic index (HSI), and increased gonadosomatic index (GSI). Females prefer males that fan more, which will favour the small EDC exposed males. This may lead to mating that favours males that are not strong enough to tend the eggs until they hatch, thus decreasing the reproductive success of individuals.

  8. Dissipative structures and biological rhythms

    Science.gov (United States)

    Goldbeter, Albert

    2017-10-01

    Sustained oscillations abound in biological systems. They occur at all levels of biological organization over a wide range of periods, from a fraction of a second to years, and with a variety of underlying mechanisms. They control major physiological functions, and their dysfunction is associated with a variety of physiological disorders. The goal of this review is (i) to give an overview of the main rhythms observed at the cellular and supracellular levels, (ii) to briefly describe how the study of biological rhythms unfolded in the course of time, in parallel with studies on chemical oscillations, (iii) to present the major roles of biological rhythms in the control of physiological functions, and (iv) the pathologies associated with the alteration, disappearance, or spurious occurrence of biological rhythms. Two tables present the main examples of cellular and supracellular rhythms ordered according to their period, and their role in physiology and pathophysiology. Among the rhythms discussed are neural and cardiac rhythms, metabolic oscillations such as those occurring in glycolysis in yeast, intracellular Ca++ oscillations, cyclic AMP oscillations in Dictyostelium amoebae, the segmentation clock that controls somitogenesis, pulsatile hormone secretion, circadian rhythms which occur in all eukaryotes and some bacteria with a period close to 24 h, the oscillatory dynamics of the enzymatic network driving the cell cycle, and oscillations in transcription factors such as NF-ΚB and tumor suppressors such as p53. Ilya Prigogine's concept of dissipative structures applies to temporal oscillations and allows us to unify within a common framework the various rhythms observed at different levels of biological organization, regardless of their period and underlying mechanism.

  9. Social context-dependent modification of courtship behaviour in Drosophila prolongata.

    Science.gov (United States)

    Setoguchi, Shiori; Kudo, Ayumi; Takanashi, Takuma; Ishikawa, Yukio; Matsuo, Takashi

    2015-11-07

    Induction of alternative mating tactics by surrounding conditions, such as the presence of conspecific males, is observed in many animal species. Satellite behaviour is a remarkable example in which parasitic males exploit the reproductive investment by other males. Despite the abundance of parasitic mating tactics, however, few examples are known in which males alter courtship behaviour as a counter tactic against parasitic rivals. The fruit fly Drosophila prolongata shows prominent sexual dimorphism in the forelegs. When courting females, males of D. prolongata perform 'leg vibration', in which a male vibrates the female's body with his enlarged forelegs. In this study, we found that leg vibration increased female receptivity, but it also raised a risk of interception of the female by rival males. Consequently, in the presence of rivals, males of D. prolongata shifted their courtship behaviour from leg vibration to 'rubbing', which was less vulnerable to interference by rival males. These results demonstrated that the males of D. prolongata adjust their courtship behaviour to circumvent the social context-dependent risk of leg vibration. © 2015 The Author(s).

  10. A role for the adult fat body in Drosophila male courtship behavior.

    Directory of Open Access Journals (Sweden)

    Anna A Lazareva

    2007-01-01

    Full Text Available Mating behavior in Drosophila depends critically on the sexual identity of specific regions in the brain, but several studies have identified courtship genes that express products only outside the nervous system. Although these genes are each active in a variety of non-neuronal cell types, they are all prominently expressed in the adult fat body, suggesting an important role for this tissue in behavior. To test its role in male courtship, fat body was feminized using the highly specific Larval serum protein promoter. We report here that the specific feminization of this tissue strongly reduces the competence of males to perform courtship. This effect is limited to the fat body of sexually mature adults as the feminization of larval fat body that normally persists in young adults does not affect mating. We propose that feminization of fat body affects the synthesis of male-specific secreted circulating proteins that influence the central nervous system. In support of this idea, we demonstrate that Takeout, a protein known to influence mating, is present in the hemolymph of adult males but not females and acts as a secreted protein.

  11. Semiochemical and Vibrational Cues and Signals Mediating Mate Finding and Courtship in Psylloidea (Hemiptera: A Synthesis

    Directory of Open Access Journals (Sweden)

    Umar K. Lubanga

    2014-07-01

    Full Text Available Mate finding and courtship involve complex interactions that require close coordination between individuals of the opposite gender. Well-organized signalling systems, sometimes involving a combination of signal modalities, are required to convey species-specific and individual information to members of the opposite gender. Previous studies of psyllids have focused on single-signal modalities and have largely ignored the potentially interdependent nature of different types of signals. Several studies have shown that semiochemicals play a role in psyllid mate finding. However, long-range semiochemical sex attractants, such as the highly volatile sex pheromones used by many Lepidoptera (molecular weights <300, are yet to be identified. The compounds identified thus far, namely 13-methylheptacosane (from Cacopsylla pyricola and dodecanoic acid (from Diaphorina citri, seem to have short range activity or no activity under field conditions. The possible role played by cuticular hydrocarbons in psyllid courtship remains largely ignored. Conversely, many psyllid species rely on vibrational signals for mate finding and mate assessment during courtship. This apparent disproportional reliance on vibrational rather than semiochemical signals suggests that vibrational signals have been more influential in sexual selection in psyllids. However, male fitness, female choice and benefits accrued from selecting fitter males remain poorly understood.

  12. Evolutionary insights into the regulation of courtship behavior in male amphibians and reptiles.

    Science.gov (United States)

    Woolley, Sarah C; Sakata, Jon T; Crews, David

    2004-11-15

    Comparative studies of species differences and similarities in the regulation of courtship behavior afford an understanding of evolutionary pressures and constraints shaping reproductive processes and the relative contributions of hormonal, genetic, and ecological factors. Here, we review species differences and similarities in the control of courtship and copulatory behaviors in male amphibians and reptiles, focusing on the role of sex steroid hormones, the neurohormone arginine vasotocin (AVT), and catecholamines. We discuss species differences in the sensory modalities used during courtship and in the neural correlates of these differences, as well as the value of particular model systems for neural evolution studies with regard to reproductive processes. For example, in some genera of amphibians (e.g., Ambystoma) and reptiles (e.g., Cnemidophorus), interspecific hybridizations occur, making it possible to compare the ancestral with the descendant species, and these systems provide a window into the process of behavioral and neural evolution as well as the effect of genome size. Though our understanding of the hormonal and neural correlates of mating behavior in a variety of amphibian and reptilian species has advanced substantially, more studies that manipulate hormone or neurotransmitter systems are required to assess the functions of these systems.

  13. How Two Players Negotiate Rhythm in a Shared Rhythm Game

    DEFF Research Database (Denmark)

    Hansen, Anne-Marie; Andersen, Hans Jørgen; Raudaskoski, Pirkko Liisa

    2012-01-01

    from each other. Video analysis of user interaction shines light upon how users engaged in a rhythmical relationship, and interviews give information about the user experience in terms of the game play and user collaboration. Based on the findings in this paper we propose design guidelines......In a design and working prototype of a shared music interface eleven teams of two people were to collaborate about filling in holes with tones and beats in an evolving ground rhythm. The hypothesis was that users would tune into each other and have sections of characteristic rhythmical...... relationships that related to the ground rhythm. Results from interaction data show that teams did find a mutual rhythm, and that they were able to keep this rhythm for a while and/or over several small periods. Results also showed that two players engaged in very specific rhythmical relationships that differed...

  14. Learning by joining the rhythm

    DEFF Research Database (Denmark)

    Lund, Ole; Ravn, Susanne; Christensen, Mette Krogh

    2012-01-01

    This article aims to explore how a joint rhythm is learned. The exploration is based on a combination of a case study of training in elite rowing and theoretical considerations concerning mutual incorporation of skills in learning. In 2009 Juliane and Anne start to row the double sculler together....... The two rowers’ aim is to be among the exclusive group of teams that qualify for the Olympic Games three years later. However Anne is not a rower, and has to be apprenticed by Juliane, who is an experienced elite rower. One important learning goal in the apprenticeship is to find a good joint rhythm......, to be able to put optimal effort into the rowing. Thus the apprenticeship is about developing a sense for a good rhythm in Anne which corresponds to Juliane’s fine-grained sense of what a good rhythm should feel like. Our study suggests that apprenticeship learning has to be understood as an embodied...

  15. Find a Heart Rhythm Specialist

    Science.gov (United States)

    ... Taiwan Thailand Turkey United Arab Emirates United Kingdom Venezuela Vietnam Within 5 miles 10 miles 15 miles ... info@HRSonline.org © Heart Rhythm Society 2017 Privacy Policy | Linking Policy | Patient Education Disclaimer You are about ...

  16. Sympathetic rhythms and nervous integration.

    Science.gov (United States)

    Gilbey, Michael P

    2007-04-01

    1. The present review focuses on some of the processes producing rhythms in sympathetic nerves influencing cardiovascular functions and considers their potential relevance to nervous integration. 2. Two mechanisms are considered that may account for rhythmic sympathetic discharges. First, neuronal elements of peripheral or central origin produce rhythmic activity by phasically exciting and/or inhibiting neurons within central sympathetic networks. Second, rhythms arise within central sympathetic networks. Evidence is considered that indicates the operation of both mechanisms; the first in muscle and the second in skin sympathetic vasoconstrictor networks. 3. Sympathetic activity to the rat tail, a model for the nervous control of skin circulation, is regulated by central networks involved in thermoregulation and those associated with fear and arousal. In an anaesthetized preparation, activity displays an apparently autonomous rhythm (T-rhythm; 0.4-1.2 Hz) and the level of activity can be manipulated by regulating core body temperature. This model has been used to study rhythm generation in central sympathetic networks and possible functional relevance. 4. A unique insight provided by the T rhythm, into possible physiological function(s) underlying rhythmic sympathetic discharges is that the activity of single sympathetic post-ganglionic neurons within a population innervating the same target can have different rhythm frequencies. Therefore, the graded and dynamic entrainment of the rhythms by inputs, such as central respiratory drive and/or lung inflation-related afferent activity, can produce graded and dynamic synchronization of sympathetic discharges. The degree of synchronization may influence the efficacy of transmission in a target chain of excitable cells. 5. The T-rhythm may be generated within the spinal cord because the intrathecal application of 5-hydroxytryptamine at the L1 level of the spinal cord of a rat spinalized at T10-T11 produces a T-like rhythm

  17. Circadian rhythms and reproduction.

    Science.gov (United States)

    Boden, Michael J; Kennaway, David J

    2006-09-01

    There is a growing recognition that the circadian timing system, in particular recently discovered clock genes, plays a major role in a wide range of physiological systems. Microarray studies, for example, have shown that the expression of hundreds of genes changes many fold in the suprachiasmatic nucleus, liver heart and kidney. In this review, we discuss the role of circadian rhythmicity in the control of reproductive function in animals and humans. Circadian rhythms and clock genes appear to be involved in optimal reproductive performance, but there are sufficient redundancies in their function that many of the knockout mice produced do not show overt reproductive failure. Furthermore, important strain differences have emerged from the studies especially between the various Clock (Circadian Locomotor Output Cycle Kaput) mutant strains. Nevertheless, there is emerging evidence that the primary clock genes, Clock and Bmal1 (Brain and Muscle ARNT-like protein 1, also known as Mop3), strongly influence reproductive competency. The extent to which the circadian timing system affects human reproductive performance is not known, in part, because many of the appropriate studies have not been done. With the role of Clock and Bmal1 in fertility becoming clearer, it may be time to pursue the effect of polymorphisms in these genes in relation to the various types of infertility in humans.

  18. Hormonal Signaling Cascade during an Early-Adult Critical Period Required for Courtship Memory Retention in Drosophila.

    Science.gov (United States)

    Lee, Sang Soo; Ding, Yike; Karapetians, Natalie; Rivera-Perez, Crisalejandra; Noriega, Fernando Gabriel; Adams, Michael E

    2017-09-25

    Formation and expression of memories are critical for context-dependent decision making. In Drosophila, a courting male rejected by a mated female subsequently courts less avidly when paired with a virgin female, a behavioral modification attributed to "courtship memory." Here we show the critical role of hormonal state for maintenance of courtship memory. Ecdysis-triggering hormone (ETH) is essential for courtship memory through regulation of juvenile hormone (JH) levels in adult males. Reduction of JH levels via silencing of ETH signaling genes impairs short-term courtship memory, a phenotype rescuable by the JH analog methoprene. JH-deficit-induced memory impairment involves rapid decay rather than failure of memory acquisition. A critical period governs memory performance during the first 3 days of adulthood. Using sex-peptide-expressing "pseudo-mated" trainers, we find that robust courtship memory elicited in the absence of aversive chemical mating cues also is dependent on ETH-JH signaling. Finally, we find that JH acts through dopaminergic neurons and conclude that an ETH-JH-dopamine signaling cascade is required during a critical period for promotion of social-context-dependent memory. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Effects of polygamy on the activity/rest rhythm of male fruit flies Drosophila melanogaster

    Science.gov (United States)

    Vartak, Vivek Rohidas; Varma, Vishwanath; Sharma, Vijay Kumar

    2015-02-01

    Although polygamy is common in insects, its extent varies enormously among natural populations. Mating systems influence the evolution of reproductive traits and the difference in extent of polygamy between males and females may be a key factor in determining traits which come under the influence of sexual selection. Fruit flies Drosophila melanogaster are promiscuous as both males and females mate with multiple partners. Mating has severe consequences on the physiology and behaviour of flies, and it affects their activity/rest rhythm in a sex-specific manner. In this study, we attempted to discern the effects of mating with multiple partners as opposed to a single partner, or of remaining unmated, on the activity/rest rhythm of flies under cyclic semi-natural (SN) and constant dark (DD) conditions. The results revealed that while evening activity of mated flies was significantly reduced compared to virgins, polygamous males showed a more severe reduction compared to monogamous males. In contrast, though mated females showed reduction in evening activity compared to virgins, activity levels were not different between polygamous and monogamous females. Although there was no detectable effect of mating on clock period, power of the activity/rest rhythm was significantly reduced in mated females with no difference seen between polygamous and monogamous individuals. These results suggest that courtship motivation, represented by evening activity, is successively reduced in males due to mating with one or more partners, while in females, it does not depend on the number of mating partners. Based on these results we conclude that polygamy affects the activity/rest rhythm of fruit flies D. melanogaster in a sex-dependent manner.

  20. Male courtship preferences demonstrate discrimination against allopatric colour morphs in a cichlid fish.

    Science.gov (United States)

    Zoppoth, P; Koblmüller, S; Sefc, K M

    2013-03-01

    Whether premating isolation is achieved by male-specific, female-specific or sex-independent assortative preferences often depends on the underlying evolutionary processes. Here we test mate preferences of males presented with females of different allopatric colour variants of the cichlid fish Tropheus sp., a Lake Tanganyika endemic with rich geographical colour pattern variation, in which the strength of sexual isolation varies between populations. We conducted two-way mate choice experiments to compare behaviour of males of a red-bodied morph (population Moliro) towards females from their own population with behaviour towards females from four allopatric populations at different stages of phylogenetic and phenotypic divergence. Males courted same-population females significantly more intensely than females of other populations, and reduced their heteromorphic courtship efforts both with increasing genetic and increasing phenotypic distinctness of the females. In particular, females of a closely related red-bodied population received significantly more courtship than either genetically distinct, similarly coloured females ('Kirschfleck' morph) or genetically related, differently coloured females ('yellow-blotch' morph), both of which were courted similarly. Genetically and phenotypically distinct females (Tropheus polli) were not courted at all. Consistent with previous female-choice experiments, female courtship activity also decreased with increasing genetic distance from the males' population. Given successful experimental and natural introgression between colour morphs and the pervasive allopatry of related variants, we consider it unlikely that assortative preferences of both sexes were driven by direct selection during periods of secondary contact or, in turn, drove colour pattern differentiation in allopatry. Rather, we suggest that sexual isolation evolved as by-product of allopatric divergence. © 2012 The Authors. Journal of Evolutionary Biology © 2012

  1. Courtship behaviour of Phlebotomus papatasi the sand fly vector of cutaneous leishmaniasis

    Directory of Open Access Journals (Sweden)

    Chelbi Ifhem

    2012-08-01

    Full Text Available Abstract Background The sand fly Phlebotomus papatasi is an Old World vector of Leishmania major, the etiologic agent of zoonotic cutaneous leishmaniasis. This study describes the courtship behaviour of P. papatasi and compares it with that of Lutzomyia longipalpis, the New World vector of visceral leishmaniasis. Understanding the details of courtship behaviour in P. papatasi may help us to understand the role of sex pheromones in this important vector. Results P. papatasi courtship was found to start with the female touching the male, leading him to begin abdomen bending and wing flapping. Following a period of leg rubbing and facing, the male flaps his wings while approaching the female. The female then briefly flaps her wings in response, to indicate that she is willing to mate, thereby signaling the male to begin copulation. Male P. papatasi did not engage in parading behaviour, which is performed by male L. longipalpis to mark out individual territories during lekking (the establishment and maintenance of mating aggregations, or wing-flap during copulation, believed to function in the production of audio signals important to mate recognition. In P. papatasi the only predictor of mating success for males was previous copulation attempts and for females stationary wing-flapping. By contrast, male L. longipalpis mating success is predicted by male approach-flapping and semi-circling behaviour and for females stationary wing-flapping. Conclusions The results show that there are important differences between the mating behaviours of P. papatasi and L. longipalpis. Abdomen bending, which does not occur in L. longipalpis, may act in the release of sex pheromone from an as yet unidentified site in the male abdomen. In male L. longipalpis wing-flapping is believed to be associated with distribution of male pheromone. These different behaviours are likely to signify significant differences in how pheromone is used, an observation that is consistent

  2. Modification of Male Courtship Motivation by Olfactory Habituation via the GABAA Receptor in Drosophila melanogaster

    Science.gov (United States)

    Tachibana, Shin-Ichiro; Touhara, Kazushige; Ejima, Aki

    2015-01-01

    A male-specific component, 11-cis-vaccenyl acetate (cVA) works as an anti-aphrodisiac pheromone in Drosophila melanogaster. The presence of cVA on a male suppresses the courtship motivation of other males and contributes to suppression of male-male homosexual courtship, while the absence of cVA on a female stimulates the sexual motivation of nearby males and enhances the male-female interaction. However, little is known how a male distinguishes the presence or absence of cVA on a target fly from either self-produced cVA or secondhand cVA from other males in the vicinity. In this study, we demonstrate that male flies have keen sensitivity to cVA; therefore, the presence of another male in the area reduces courtship toward a female. This reduced level of sexual motivation, however, could be overcome by pretest odor exposure via olfactory habituation to cVA. Real-time imaging of cVA-responsive sensory neurons using the neural activity sensor revealed that prolonged exposure to cVA decreased the levels of cVA responses in the primary olfactory center. Pharmacological and genetic screening revealed that signal transduction via GABAA receptors contributed to this olfactory habituation. We also found that the habituation experience increased the copulation success of wild-type males in a group. In contrast, transgenic males, in which GABA input in a small subset of local neurons was blocked by RNAi, failed to acquire the sexual advantage conferred by habituation. Thus, we illustrate a novel phenomenon in which olfactory habituation positively affects sexual capability in a competitive environment. PMID:26252206

  3. Moths produce extremely quiet ultrasonic courtship songs by rubbing specialized scales

    DEFF Research Database (Denmark)

    Nakano, Ryo; Skals, Niels; Takanashi, Takuma

    2008-01-01

    level at 1 cm) adapted for private sexual communication in the Asian corn borer moth, Ostrinia furnacalis. During courtship, the male rubs specialized scales on the wing against those on the thorax to produce the songs, with the wing membrane underlying the scales possibly acting as a sound resonator....... The male's song suppresses the escape behavior of the female, thereby increasing his mating success. Our discovery of extremely low-intensity ultrasonic communication may point to a whole undiscovered world of private communication, using "quiet" ultrasound....

  4. Expression of human PQBP-1 in Drosophila impairs long-term memory and induces abnormal courtship.

    Science.gov (United States)

    Yoshimura, Natsue; Horiuchi, Daisuke; Shibata, Masao; Saitoe, Minoru; Qi, Mei-Ling; Okazawa, Hitoshi

    2006-04-17

    Frame shift mutations of the polyglutamine binding protein-1 (PQBP1) gene lead to total or partial truncation of the C-terminal domain (CTD) and cause mental retardation in human patients. Interestingly, normal Drosophila homologue of PQBP-1 lacks CTD. As a model to analyze the molecular network of PQBP-1 affecting intelligence, we generated transgenic flies expressing human PQBP-1 with CTD. Pavlovian olfactory conditioning revealed that the transgenic flies showed disturbance of long-term memory. In addition, they showed abnormal courtship that male flies follow male flies. Abnormal functions of PQBP-1 or its binding partner might be linked to these symptoms.

  5. Drosophila pheromone-sensing neurons expressing the ppk25 ion channel subunit stimulate male courtship and female receptivity.

    Science.gov (United States)

    Vijayan, Vinoy; Thistle, Rob; Liu, Tong; Starostina, Elena; Pikielny, Claudio W

    2014-03-01

    As in many species, gustatory pheromones regulate the mating behavior of Drosophila. Recently, several ppk genes, encoding ion channel subunits of the DEG/ENaC family, have been implicated in this process, leading to the identification of gustatory neurons that detect specific pheromones. In a subset of taste hairs on the legs of Drosophila, there are two ppk23-expressing, pheromone-sensing neurons with complementary response profiles; one neuron detects female pheromones that stimulate male courtship, the other detects male pheromones that inhibit male-male courtship. In contrast to ppk23, ppk25, is only expressed in a single gustatory neuron per taste hair, and males with impaired ppk25 function court females at reduced rates but do not display abnormal courtship of other males. These findings raised the possibility that ppk25 expression defines a subset of pheromone-sensing neurons. Here we show that ppk25 is expressed and functions in neurons that detect female-specific pheromones and mediates their stimulatory effect on male courtship. Furthermore, the role of ppk25 and ppk25-expressing neurons is not restricted to responses to female-specific pheromones. ppk25 is also required in the same subset of neurons for stimulation of male courtship by young males, males of the Tai2 strain, and by synthetic 7-pentacosene (7-P), a hydrocarbon normally found at low levels in both males and females. Finally, we unexpectedly find that, in females, ppk25 and ppk25-expressing cells regulate receptivity to mating. In the absence of the third antennal segment, which has both olfactory and auditory functions, mutations in ppk25 or silencing of ppk25-expressing neurons block female receptivity to males. Together these results indicate that ppk25 identifies a functionally specialized subset of pheromone-sensing neurons. While ppk25 neurons are required for the responses to multiple pheromones, in both males and females these neurons are specifically involved in stimulating

  6. Timing of host feeding drives rhythms in parasite replication

    KAUST Repository

    Prior, Kimberley F.; van der Veen, Daan R.; O’ Donnell, Aidan J.; Cumnock, Katherine; Schneider, David; Pain, Arnab; Subudhi, Amit; Ramaprasad, Abhinay; Rund, Samuel S. C.; Savill, Nicholas J.; Reece, Sarah E.

    2018-01-01

    by the central, light-entrained circadian oscillator in the brain, determine the timing (phase) of parasite rhythms. Further investigation reveals that parasite rhythms correlate closely with blood glucose rhythms. In addition, we show that parasite rhythms

  7. Male courtship behavior in Ceratitis Capitata (Diptera: Tephritidae) that have received Aromatherapy with ginger root oil

    International Nuclear Information System (INIS)

    Briceno, D.; Eberhard, W.; Shelly, T.

    2007-01-01

    The results of previous studies that showed that exposing mass-reared male Mediterranean fruit flies Ceratitis capitata (Wiedemann) to ginger root oil ('aromatherapy') increases the likelihood of mating with wild females were confirmed. The increased male success could be due to female responses to changes in male behavior or male pheromones. There were no significant differences in the types of courtship movements executed by males with and without aromatherapy. The durations of movements also did not differ when mass-reared males were paired with mass-reared females; however, when they were paired with wild females, there were a few, small differences. Previous studies indicated that the effectiveness of the male long-distance attractant pheromone is not affected by aromatherapy, but these studies did not consider pheromones released at close range during courtship, which behavioral analyses suggest may be different. We propose the following possible explanation for the different effects of aromatherapy with different females. Selection on males under mass rearing may have altered their close-range pheromones in ways that can be remedied by aromatherapy; and only wild females respond because the pheromonal responsiveness of mass-reared females has also changed. We propose observations that could test these ideas. (author) [es

  8. Highly tissue specific expression of Sphinx supports its male courtship related role in Drosophila melanogaster.

    Science.gov (United States)

    Chen, Ying; Dai, Hongzheng; Chen, Sidi; Zhang, Luoying; Long, Manyuan

    2011-04-26

    Sphinx is a lineage-specific non-coding RNA gene involved in regulating courtship behavior in Drosophila melanogaster. The 5' flanking region of the gene is conserved across Drosophila species, with the proximal 300 bp being conserved out to D. virilis and a further 600 bp region being conserved amongst the melanogaster subgroup (D. melanogaster, D. simulans, D. sechellia, D. yakuba, and D. erecta). Using a green fluorescence protein transformation system, we demonstrated that a 253 bp region of the highly conserved segment was sufficient to drive sphinx expression in male accessory gland. GFP signals were also observed in brain, wing hairs and leg bristles. An additional ∼800 bp upstream region was able to enhance expression specifically in proboscis, suggesting the existence of enhancer elements. Using anti-GFP staining, we identified putative sphinx expression signal in the brain antennal lobe and inner antennocerebral tract, suggesting that sphinx might be involved in olfactory neuron mediated regulation of male courtship behavior. Whole genome expression profiling of the sphinx knockout mutation identified significant up-regulated gene categories related to accessory gland protein function and odor perception, suggesting sphinx might be a negative regulator of its target genes.

  9. Highly tissue specific expression of Sphinx supports its male courtship related role in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Ying Chen

    2011-04-01

    Full Text Available Sphinx is a lineage-specific non-coding RNA gene involved in regulating courtship behavior in Drosophila melanogaster. The 5' flanking region of the gene is conserved across Drosophila species, with the proximal 300 bp being conserved out to D. virilis and a further 600 bp region being conserved amongst the melanogaster subgroup (D. melanogaster, D. simulans, D. sechellia, D. yakuba, and D. erecta. Using a green fluorescence protein transformation system, we demonstrated that a 253 bp region of the highly conserved segment was sufficient to drive sphinx expression in male accessory gland. GFP signals were also observed in brain, wing hairs and leg bristles. An additional ∼800 bp upstream region was able to enhance expression specifically in proboscis, suggesting the existence of enhancer elements. Using anti-GFP staining, we identified putative sphinx expression signal in the brain antennal lobe and inner antennocerebral tract, suggesting that sphinx might be involved in olfactory neuron mediated regulation of male courtship behavior. Whole genome expression profiling of the sphinx knockout mutation identified significant up-regulated gene categories related to accessory gland protein function and odor perception, suggesting sphinx might be a negative regulator of its target genes.

  10. Female genitalia concealment promotes intimate male courtship in a water strider.

    Directory of Open Access Journals (Sweden)

    Chang S Han

    2009-06-01

    Full Text Available Violent coercive mating initiation is typical for animals with sexual conflict over mating. In these species, the coevolutionary arms-race between female defenses against coercive mating and male counter-adaptations for increased mating success leads to coevolutionary chases of male and female traits that influence the mating. It has been controversial whether one of the sexes can evolve traits that allow them to "win" this arms race. Here, we use morphological analysis (traditional and scanning electron micrographs, laboratory experiments and comparative methods to show how females of a species characterized by typical coercive mating initiation appear to "win" a particular stage of the sexual conflict by evolving morphology to hide their genitalia from direct, forceful access by males. In an apparent response to the female morphological adaptation, males of this species added to their typically violent coercive mounting of the female new post-mounting, pre-copulatory courtship signals produced by tapping the water's surface with the mid-legs. These courtship signals are intimate in the sense that they are aimed at the female, on whom the male is already mounted. Females respond to the signals by exposing their hidden genitalia for copulatory intromission. Our results indicate that the apparent victory of coevolutionary arms race by one sex in terms of morphology may trigger evolution of a behavioral phenotype in the opposite sex.

  11. Behavioral and neural lateralization of vision in courtship singing of the zebra finch.

    Science.gov (United States)

    George, Isabelle; Hara, Erina; Hessler, Neal A

    2006-09-01

    Along with human speech and language processing, birdsong has been one of the best-characterized model systems for understanding the relationship of lateralization of brain function to behavior. Lateralization of song production has been extensively characterized, and lateralization of song perception has begun to be studied. Here we have begun to examine whether behavior and brain function are lateralized in relation to communicative aspects of singing, as well. In order to monitor central brain function, we assayed the levels of several activity dependent immediate early genes after directed courtship singing. Consistent with a lateralization of visual processing during communication, there were higher levels of expression of both egr-1 and c-fos in the left optic tectum after directed singing. Because input from the eyes to the brain is almost completely contralateral in birds, these results suggest that visual input from the right eye should be favored during normal singing to females. Consistent with this, we further found that males sang more when they could use only their right eye compared to when they could use only their left eye. Normal levels of singing, though, required free use of both eyes to view the female. These results suggest that there is a preference for visual processing by the right eye and left brain hemisphere during courtship singing. This may reflect a proposed specialization of the avian left hemisphere in sustaining attention on stimuli toward which a motor response is planned.

  12. Acoustic courtship songs in males of the fruit fly Anastrepha ludens (Diptera: Tephritidae associated with geography, mass rearing and courtship success

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    R.D Briceño

    2009-11-01

    Full Text Available The Sterile Insect Technique (SIT has been used successfully to control or eradicate fruit flies. The commonly observed inferiority of mass-reared males, compared with wild males, when they are paired with wild females, is apparently due to their inadequate courtship. Anastrepha ludens males produce two types of wing vibration during courtship and mating, the "calling sound" and the "premating or precopulatory sound". There were clear differences in the calling songs between successful and unsuccessful courtships in sterile (irradiated and fertile Mexican flies. Among sterile flies, successful males produce longer buzzes, shorter interpulses and a higher power spectrum in the signal. Fertile flies showed the same trend. For mating songs a significant difference occurred in two parameters: power spectrum between sterile and fertile flies with respect to the type of song, and the signal duration and intensity were greater in non-irradiated flies. Calling songs of wild flies compared with laboratory grown flies from Mexico had shorter interpulses, longer pulses, and a greater power spectrum. However, in the case of premating songs, the only difference was in the intensity, which was significantly greater in wild males. An unexpected result was not observing pulses during pheromone deposition in wild males from Costa Rica. Comparing the premating songs of wild flies from Costa Rica and Mexico, no significant differences were observed in the duration, and the intensity of the signal was slightly greater in flies from Mexico. Rev. Biol. Trop. 57 (Suppl. 1: 257-265. Epub 2009 November 30.La técnica estéril del insecto (SIT se ha utilizado con éxito para controlar o para suprimir las moscas de fruta y su impacto en los cultivos. La inferioridad comúnmente observada de machos criados masivamente, comparada con los machos silvestres, cuando se aparean con las hembras silvestres es al parecer debido a su inadecuado cortejo. Los machos de Anastrepha

  13. Circadian rhythms in mitochondrial respiration

    NARCIS (Netherlands)

    de Goede, Paul; Wefers, Jakob; Brombacher, Eline Constance; Schrauwen, P; Kalsbeek, A.

    2018-01-01

    Many physiological processes are regulated with a 24h periodicity to anticipate the environmental changes of day to nighttime and vice versa. These 24h regulations, commonly termed circadian rhythms, amongst others control the sleep-wake cycle, locomotor activity and preparation for food

  14. Rhythm Deficits in "Tone Deafness"

    Science.gov (United States)

    Foxton, Jessica M.; Nandy, Rachel K.; Griffiths, Timothy D.

    2006-01-01

    It is commonly observed that "tone deaf" individuals are unable to hear the beat of a tune, yet deficits on simple timing tests have not been found. In this study, we investigated rhythm processing in nine individuals with congenital amusia ("tone deafness") and nine controls. Participants were presented with pairs of 5-note sequences, and were…

  15. Singing-Related Activity in Anterior Forebrain of Male Zebra Finches Reflects Courtship Motivation for Target Females

    Science.gov (United States)

    Iwasaki, Mai; Poulsen, Thomas M.; Oka, Kotaro; Hessler, Neal A.

    2013-01-01

    A critical function of singing by male songbirds is to attract a female mate. Previous studies have suggested that the anterior forebrain system is involved in this courtship behavior. Neural activity in this system, including the striatal Area X, is strikingly dependent on the function of male singing. When males sing to attract a female bird rather than while alone, less variable neural activity results in less variable song spectral features, which may be attractive to the female. These characteristics of neural activity and singing thus may reflect a male's motivation for courtship. Here, we compared the variability of neural activity and song features between courtship singing directed to a female with whom a male had previously formed a pair-bond or to other females. Surprisingly, across all units, there was no clear tendency for a difference in variability of neural activity or song features between courtship of paired females, nonpaired females, or dummy females. However, across the population of recordings, there was a significant relationship between the relative variability of syllable frequency and neural activity: when syllable frequency was less variable to paired than nonpaired females, neural activity was also less variable (and vice-versa). These results show that the lower variability of neural activity and syllable frequency during directed singing is not a binary distinction from undirected singing, but can vary in intensity, possibly related to the relative preference of a male for his singing target. PMID:24312344

  16. Evolution of multiple additive loci caused divergence between Drosophila yakuba and D. santomea in wing rowing during male courtship.

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    Jessica Cande

    Full Text Available In Drosophila, male flies perform innate, stereotyped courtship behavior. This innate behavior evolves rapidly between fly species, and is likely to have contributed to reproductive isolation and species divergence. We currently understand little about the neurobiological and genetic mechanisms that contributed to the evolution of courtship behavior. Here we describe a novel behavioral difference between the two closely related species D. yakuba and D. santomea: the frequency of wing rowing during courtship. During courtship, D. santomea males repeatedly rotate their wing blades to face forward and then back (rowing, while D. yakuba males rarely row their wings. We found little intraspecific variation in the frequency of wing rowing for both species. We exploited multiplexed shotgun genotyping (MSG to genotype two backcross populations with a single lane of Illumina sequencing. We performed quantitative trait locus (QTL mapping using the ancestry information estimated by MSG and found that the species difference in wing rowing mapped to four or five genetically separable regions. We found no evidence that these loci display epistasis. The identified loci all act in the same direction and can account for most of the species difference.

  17. Human biological rhythm in traditional Chinese medicine

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    Tianxing Zhang

    2016-10-01

    Full Text Available Traditional Chinese medicine (TCM has a comprehensive and thorough understanding of biological rhythm. Biological rhythm is an inherent connotation of “harmony between human and nature”, one of the thoughts in TCM. TCM discusses emphatically circadian rhythm, syzygial rhythm and seasonal rhythm, and particularly circadian and seasonal rhythms. Theories of Yin Yang and Five Elements are the principles and methods, with which TCM understands biological rhythms. Based on theories in TCM, biological rhythm in essence is a continuous variation of the human body state synchronized with natural rhythms, and theories of Yin Yang and Five Elements are both language tools to describe this continuous variation and theoretical tools for its investigation and application. The understandings of biological rhythm in TCM can be applied to etiology, health care, disease control and treatment. Many understandings in TCM have been confirmed by modern research and clinical reports, but there are still some pending issues. TCM is distinguished for its holistic viewpoint on biological rhythms.

  18. Ischemic stroke destabilizes circadian rhythms

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    Borjigin Jimo

    2008-10-01

    Full Text Available Abstract Background The central circadian pacemaker is a remarkably robust regulator of daily rhythmic variations of cardiovascular, endocrine, and neural physiology. Environmental lighting conditions are powerful modulators of circadian rhythms, but regulation of circadian rhythms by disease states is less clear. Here, we examine the effect of ischemic stroke on circadian rhythms in rats using high-resolution pineal microdialysis. Methods Rats were housed in LD 12:12 h conditions and monitored by pineal microdialysis to determine baseline melatonin timing profiles. After demonstration that the circadian expression of melatonin was at steady state, rats were subjected to experimental stroke using two-hour intralumenal filament occlusion of the middle cerebral artery. The animals were returned to their cages, and melatonin monitoring was resumed. The timing of onset, offset, and duration of melatonin secretion were calculated before and after stroke to determine changes in circadian rhythms of melatonin secretion. At the end of the monitoring period, brains were analyzed to determine infarct volume. Results Rats demonstrated immediate shifts in melatonin timing after stroke. We observed a broad range of perturbations in melatonin timing in subsequent days, with rats exhibiting onset/offset patterns which included: advance/advance, advance/delay, delay/advance, and delay/delay. Melatonin rhythms displayed prolonged instability several days after stroke, with a majority of rats showing a day-to-day alternation between advance and delay in melatonin onset and duration. Duration of melatonin secretion changed in response to stroke, and this change was strongly determined by the shift in melatonin onset time. There was no correlation between infarct size and the direction or amplitude of melatonin phase shifting. Conclusion This is the first demonstration that stroke induces immediate changes in the timing of pineal melatonin secretion, indicating

  19. Characterization of courtship sounds of species of the subgroup fasciola (Diptera, Drosophilidae, Drosophila repleta group: interspecific and interpopulational analyses

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    C. T. A. COSTA

    Full Text Available The aim of this work was to characterize the male courtship song pattern of various species of the fasciola subgroup and to determine the level of variation both within and among species. The parameters analyzed were intrapulse interval (PI, interpulse interval (IPI, and intrapulse frequency (IF. Six different species were analyzed: D. coroica (three populations, D. ellisoni, D. fascioloides, D. moju, D. onca, and D. rosinae (one population each. There were significant differences among the six species for these three courtship song parameters. The IPI was the most variable parameter among these species, suggesting that this parameter is important for female discrimination. Four different hypotheses could explain this variation: 1. different selection pressures with absence of flow gene; 2. intraspecific sexual selection; 3. sympatric effects on song evolution; and 4. genetic drift. The PI was the only parameter that was significantly different among the three population of D. coroica. Low variability among populations within the same species was already observed for other subgroups and could be explained by the following hypotheses: strong selection acting on the song parameters, gene flow, or recent colonization from a common source. Additional studies of the courtship song of other species of the fasciola subgroup, as well as for other subgroups of the repleta group, and studies, using molecular makers, that focus on the genetic basis of the differences among these species in courtship song would allow us to evaluate the association of courtship song and sexual isolation in these species, and would also help us to understand the evolution of these behavioural differences.

  20. Temporal interactions between cortical rhythms

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    Anita K Roopun

    2008-12-01

    Full Text Available Multiple local neuronal circuits support different, discrete frequencies of network rhythm in neocortex. Relationships between different frequencies correspond to mechanisms designed to minimise interference, couple activity via stable phase interactions, and control the amplitude of one frequency relative to the phase of another. These mechanisms are proposed to form a framework for spectral information processing. Individual local circuits can also transform their frequency through changes in intrinsic neuronal properties and interactions with other oscillating microcircuits. Here we discuss a frequency transformation in which activity in two coactive local circuits may combine sequentially to generate a third frequency whose period is the concatenation sum of the original two. With such an interaction, the intrinsic periodicity in each component local circuit is preserved – alternate, single periods of each original rhythm form one period of a new frequency - suggesting a robust mechanism for combining information processed on multiple concurrent spatiotemporal scales.

  1. Circadian Rhythm Control: Neurophysiological Investigations

    Science.gov (United States)

    Glotzbach, S. F.

    1985-01-01

    The suprachiasmatic nucleus (SCN) was implicated as a primary component in central nervous system mechanisms governing circadian rhythms. Disruption of the normal synchronization of temperature, activity, and other rhythms is detrimental to health. Sleep wake disorders, decreases in vigilance and performance, and certain affective disorders may result from or be exacerbated by such desynchronization. To study the basic neurophysiological mechanisms involved in entrainment of circadian systems by the environment, Parylene-coated, etched microwire electrode bundles were used to record extracellular action potentials from the small somata of the SCN and neighboring hypothalamic nuclei in unanesthetized, behaving animals. Male Wistar rats were anesthetized and chronically prepared with EEG ane EMG electrodes in addition to a moveable microdrive assembly. The majority of cells had firing rates 10 Hz and distinct populations of cells which had either the highest firing rate or lowest firing rate during sleep were seen.

  2. Is courtship intensity a signal of male parental care in Red-winged Blackbirds (Agelaius phoeniceus)?

    Science.gov (United States)

    Yasukawa, Ken; Knight, Richard L.; Skagen, Susan Knight

    1987-01-01

    We studied Red-winged Blackbird (Agelaius phoeniceus) behavior in marsh and prairie habitats to determine whether courting males provide cues of their nest defense, whether females prefer males that defend nests vigorously, and whether male nest defense affects nest success. We found no evidence that courtship behavior provides cues of male nest defense, or that females prefer males that court intensely. We found evidence that females nesting in marshes prefer males that defend nests intensely, but no evidence that intensely defending males in the prairie habitat achieve high nest success. We found differences, however, between marsh and prairie habitats that suggest a coarse-grained relationship between male parental quality and female choice of mate in this species.

  3. To females of a noctuid moth, male courtship songs are nothing more than bat echolocation calls

    DEFF Research Database (Denmark)

    Nakano, Ryo; Takanashi, Takuma; Skals, Niels

    2010-01-01

    It has been proposed that intraspecific ultrasonic communication observed in some moths evolved, through sexual selection, subsequent to the development of ears sensitive to echolocation calls of insectivorous bats. Given this scenario, the receiver bias model of signal evolution argues that acou......It has been proposed that intraspecific ultrasonic communication observed in some moths evolved, through sexual selection, subsequent to the development of ears sensitive to echolocation calls of insectivorous bats. Given this scenario, the receiver bias model of signal evolution argues...... production in the male moth, and subsequently the role of the sound with reference to the female's ability to discriminate male courtship songs from bat calls. We found that males have sex-specific tymbals for ultrasound emission, and that the broadcast of either male songs or simulated bat calls equally...

  4. Persistent activity in a recurrent circuit underlies courtship memory in Drosophila

    Science.gov (United States)

    Zhao, Xiaoliang; Lenek, Daniela; Dag, Ugur; Dickson, Barry J

    2018-01-01

    Recurrent connections are thought to be a common feature of the neural circuits that encode memories, but how memories are laid down in such circuits is not fully understood. Here we present evidence that courtship memory in Drosophila relies on the recurrent circuit between mushroom body gamma (MBγ), M6 output, and aSP13 dopaminergic neurons. We demonstrate persistent neuronal activity of aSP13 neurons and show that it transiently potentiates synaptic transmission from MBγ>M6 neurons. M6 neurons in turn provide input to aSP13 neurons, prolonging potentiation of MBγ>M6 synapses over time periods that match short-term memory. These data support a model in which persistent aSP13 activity within a recurrent circuit lays the foundation for a short-term memory. PMID:29322941

  5. Sexual courtship of steriles males of Ceratitis Capitata (WIED) in SIT program

    International Nuclear Information System (INIS)

    Fadhel, Salma

    2008-01-01

    In the SIT programme, the success of sterile males to compete with the fertile males is an important parameter for assuring efficiency. In this study, two methods are tested to improve the sterile male quality: the first is the exposure of sterile males to different concentrations of Ginger Root Oil (GRO) (0, 20, 50 and 80 μl), the second is the exposure of males to different irradiation doses (80, 90, 100, 110, 120 and 145 Gy). The comparison of these methods depends to study of quality parameters (emergence, flight ability, survival) and courtship behaviour of sterile males (sperm production, mating competitiveness, sperm transfer). The 80μl concentration of GRO improves the mating competitiveness of males to compare with the Control (respectively: 68% and 46%). The 80 Gy irradiation dose assure the same result then the Control. (Author)

  6. The dating mind: evolutionary psychology and the emerging science of human courtship.

    Science.gov (United States)

    Oesch, Nathan; Miklousic, Igor

    2012-12-20

    In the New York Times bestselling book The Game: Penetrating the Secret Society of Pickup Artists (2006), the world was granted its first exclusive introduction to the steadily growing dating coach and pick-up artist community. Many of its most prominent authorities claim to use insights and information gleaned both through first-hand experience as well as empirical research in evolutionary psychology. One of the industry's most well-respected authorities, the illusionist Erik von Markovik, promotes a three-phase model of human courtship: Attraction, building mutual Comfort and Trust, and Seduction. The following review argues that many of these claims are in fact grounded in solid empirical findings from social, physiological and evolutionary psychology. Two texts which represent much of this literature are critiqued and their implications discussed.

  7. Persistent activity in a recurrent circuit underlies courtship memory in Drosophila.

    Science.gov (United States)

    Zhao, Xiaoliang; Lenek, Daniela; Dag, Ugur; Dickson, Barry J; Keleman, Krystyna

    2018-01-11

    Recurrent connections are thought to be a common feature of the neural circuits that encode memories, but how memories are laid down in such circuits is not fully understood. Here we present evidence that courtship memory in Drosophila relies on the recurrent circuit between mushroom body gamma (MBγ), M6 output, and aSP13 dopaminergic neurons. We demonstrate persistent neuronal activity of aSP13 neurons and show that it transiently potentiates synaptic transmission from MBγ>M6 neurons. M6 neurons in turn provide input to aSP13 neurons, prolonging potentiation of MB γ >M6 synapses over time periods that match short-term memory. These data support a model in which persistent aSP13 activity within a recurrent circuit lays the foundation for a short-term memory. © 2018, Zhao et al.

  8. Variation in courtship ultrasounds of three Ostrinia moths with different sex pheromones

    DEFF Research Database (Denmark)

    Takanashi, Takuma; Nakano, Ryo; Surlykke, Annemarie

    2010-01-01

    energy at 40 kHz, but distinctly different from the ultrasound produced by O. furnacalis, consisting of groups of pulses peaking at 50 kHz and with substantially more energy up to 80 kHz. Despite overall similarities, temporal features and patterns of amplitude modulation differed significantly among...... the geographic populations of O. nubilalis and O. scapulalis, which differed in pheromone type. In contrast, no significant difference in hearing was found among the three species with regard to the most sensitive frequencies and hearing threshold levels. The patterns of variations in the songs and pheromones...... well reflected those of the phylogenetic relationships, implying that ultrasound and pheromone communications have diverged concordantly. Our results suggest that concordant evolution in sexual signals such as courtship ultrasounds and sex pheromones occurs in moths....

  9. Biological Rhythms in the Skin

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    Mary S. Matsui

    2016-05-01

    Full Text Available Circadian rhythms, ≈24 h oscillations in behavior and physiology, are reflected in all cells of the body and function to optimize cellular functions and meet environmental challenges associated with the solar day. This multi-oscillatory network is entrained by the master pacemaker located in the suprachiasmatic nucleus (SCN of the hypothalamus, which directs an organism’s rhythmic expression of physiological functions and behavior via a hierarchical system. This system has been highly conserved throughout evolution and uses transcriptional–translational autoregulatory loops. This master clock, following environmental cues, regulates an organism’s sleep pattern, body temperature, cardiac activity and blood pressure, hormone secretion, oxygen consumption and metabolic rate. Mammalian peripheral clocks and clock gene expression have recently been discovered and are present in all nucleated cells in our body. Like other essential organ of the body, the skin also has cycles that are informed by this master regulator. In addition, skin cells have peripheral clocks that can function autonomously. First described in 2000 for skin, this review summarizes some important aspects of a rapidly growing body of research in circadian and ultradian (an oscillation that repeats multiple times during a 24 h period cutaneous rhythms, including clock mechanisms, functional manifestations, and stimuli that entrain or disrupt normal cycling. Some specific relationships between disrupted clock signaling and consequences to skin health are discussed in more depth in the other invited articles in this IJMS issue on Sleep, Circadian Rhythm and Skin.

  10. Serial binary interval ratios improve rhythm reproduction.

    Science.gov (United States)

    Wu, Xiang; Westanmo, Anders; Zhou, Liang; Pan, Junhao

    2013-01-01

    Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8), non-binary integer (1:3:5:6), and non-integer (1:2.3:5.3:6.4) ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

  11. Serial binary interval ratios improve rhythm reproduction

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    Xiang eWu

    2013-08-01

    Full Text Available Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8, non-binary integer (1:3:5:6, and non-integer (1:2.3:5.3:6.4 ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

  12. Female novelty and the courtship behavior of male guinea pigs (Cavia porcellus

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    Cohn D.W.H.

    2004-01-01

    Full Text Available In several rodent species, an increase or recovery of sexual behavior can be observed when sexually satiated males are placed in contact with a novel mate. In order to assess the influence of female novelty on the courtship behavior of guinea pigs (Cavia porcellus, four adult males were observed during four daily 15-min sessions while interacting with the same pregnant female (same-female sessions. A new female was presented during the fifth session (switched-female session. The duration of behavioral categories was obtained from videotape records using an observational software. From the first to the second session, all males decreased the time allocated to investigating (sniffing and licking, following, and mounting the female, and that response did not recover by the end of the same-female sessions. No similar decreasing tendencies were detected in the circling or rumba categories. A marked increase of investigating occurred in all males from the last same-female session (8.1, 11.9, 15.1 and 17.3 percent session time to the switched-female one (16.4, 18.4, 37.1 and 28.9 percent session time, respectively. Increases in following and circling were recorded in three of four males, and full-blown recovery of mounting in one male. No consistent changes in the females' responses to males (following or attacking were observed throughout testing. These results are consistent with the hypothesis that guinea pig males recognize individual females and that courtship responses may suffer a habituation/recovery process controlled by mate novelty.

  13. Acquisition of speech rhythm in first language.

    Science.gov (United States)

    Polyanskaya, Leona; Ordin, Mikhail

    2015-09-01

    Analysis of English rhythm in speech produced by children and adults revealed that speech rhythm becomes increasingly more stress-timed as language acquisition progresses. Children reach the adult-like target by 11 to 12 years. The employed speech elicitation paradigm ensured that the sentences produced by adults and children at different ages were comparable in terms of lexical content, segmental composition, and phonotactic complexity. Detected differences between child and adult rhythm and between rhythm in child speech at various ages cannot be attributed to acquisition of phonotactic language features or vocabulary, and indicate the development of language-specific phonetic timing in the course of acquisition.

  14. Factors influencing circadian rhythms in acetaminophen lethality.

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    Schnell, R C; Bozigian, H P; Davies, M H; Merrick, B A; Park, K S; McMillan, D A

    1984-01-01

    Experiments were conducted to examine the effects of changes in lighting schedules and food consumption on circadian rhythms in acetaminophen lethality and hepatic glutathione levels in male mice. Under a normal lighting schedule (light: 06.00-18.00 h), male mice exhibited a circadian rhythm in acetaminophen lethality (peak: 18.00 h; nadir: 06.00, 10.00 h) and an inverse rhythm in hepatic glutathione concentrations (peak: 06.00, 10.00 h; nadir: 18.00 h). Under a reversed lighting schedule (light: 18.00-06.00 h) the glutathione rhythm was reversed and the rhythm in acetaminophen lethality was altered showing greater sensitivity to the drug. Under continuous light, there was a shift in the acetaminophen lethality and the hepatic glutathione rhythms. Under continuous dark, both rhythms were abolished. Under a normal lighting regimen, hepatic glutathione levels were closely correlated with food consumption; i.e., both were increased during the dark phase and decreased during the light phase. Fasting the mice for 12 h abolished the rhythms in acetaminophen lethality and hepatic glutathione levels; moreover, the lethality was increased and the hepatic glutathione levels were decreased. These experiments show that both lighting schedules and feeding can alter the circadian rhythms in acetaminophen lethality and hepatic glutathione levels in male mice.

  15. Courtship and mating of Scorpiops luridus Zhu Lourenço & Qi, 2005 (Scorpiones: Euscorpiidae from Xizang province, China

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    GB Jiao

    2010-01-01

    Full Text Available In the current work, the courtship and mating of Scorpiops luridus Zhu Lourenço & Qi, 2005 (Euscorpiidae from Xizang province (Tibet, China, were studied for the first time in the laboratory. Most of the mating behaviors in Scorpiops luridus are not remarkably different from those exhibited by other scorpions. However, for the first time a male pulling a female with its chelicerae to rapidly accomplish the sperm uptake was observed. Additionally, the sexual stinging behavior displayed by the male occurred in the initial stage, not during the promenade stage as previously described in several scorpion species. Through observation and analysis, we speculate that venom injection during sexual stinging is selective, possibly relying on the status shown by the stung scorpion (passive or aggressive. In order to clearly describe the process of courtship and mating, both sequences are represented in a flow chart, while the main behavior components of these processes were identified, analyzed and discussed.

  16. Digest: Context matters: the effects of light environment and female presence on the structure of wolf spider courtship displays.

    Science.gov (United States)

    Fialko, Kristina

    2018-03-31

    Does variation in the environment in which a signal is presented affect the components of a complex, ritualized animal display? Using a signal phenotype network, Rosenthal et al. (2018) find that light and female presence alter the structure of wolf spider courtship displays, providing evidence that complex signaling behaviors may be modified depending on the social and environmental context. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  17. Genetics of sexual isolation based on courtship song between two sympatric species: Drosophila ananassae and D. pallidosa.

    Science.gov (United States)

    Yamada, Hirokazu; Matsuda, Muneo; Oguma, Yuzuru

    2002-11-01

    Sexual isolation has been considered one of the primary causes of speciation and its genetic study has the potential to reveal the genetics of speciation. In Drosophila, the importance of courtship songs in sexual isolation between closely related species has been well investigated, but studies analysing the genetic basis of the difference in the courtship songs associated with sexual isolation are less well documented. Drosophila ananassae and Drosophila pallidosa are useful for studies of sexual isolation, because of their sympatric distribution and absence of postmating isolation. Courtship songs are known to play a crucial role in sexual isolation between these two species, and the female discrimination behaviour against the courting male has been revealed to be controlled by a very narrow region on the second chromosome. In this study we investigated the genetic basis controlling the song differences associated with their sexual isolation, using intact and wingless males with chromosomes substituted between species. The results obtained from F1 hybrid males between these species indicate the dominance of the song characters favoured by D. pallidosa females. In addition, the results obtained from backcross F2 males indicate that chromosome 2 had a major effect on the control of the song characters associated with sexual isolation.

  18. Analysis of Handwriting based on Rhythm Perception

    Science.gov (United States)

    Saito, Kazuya; Uchida, Masafumi; Nozawa, Akio

    Humanity fluctuation was reported in some fields. In handwriting process, fluctuation appears on handwriting-velocity. In this report, we focused attention on human rhythm perception and analyzed fluctuation in handwriting process. As a result, 1/f noise related to rhythm perception and features may caused by Kahneman's capacity model were measured on handwriting process.

  19. Development of cortisol circadian rhythm in infancy.

    NARCIS (Netherlands)

    Weerth, C. de; Zijl, R.H.

    2003-01-01

    BACKGROUND AND AIMS: Cortisol is the final product of the hypothalamus-pituitary-adrenal (HPA) axis. It is secreted in a pulsatile fashion that displays a circadian rhythm. Infants are born without a circadian rhythm in cortisol and they acquire it during their first year of life. Studies do not

  20. Measurement of the occipital alpha rhythm and temporal tau rhythm by using magnetoencephalography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. E.; Gohel, Bakul; Kim, K.; Kwon, H.; An, Kyung Min [Center for Biosignals, Korea Research Institute of Standards and Science(KRISS), Daejeon (Korea, Republic of)

    2015-12-15

    Developing Magnetoencephalography (MEG) based on Superconducting Quantum Interference Device (SQUID) facilitates to observe the human brain functions in non-invasively and high temporal and high spatial resolution. By using this MEG, we studied alpha rhythm (8-13 Hz) that is one of the most predominant spontaneous rhythm in human brain. The 8–13 Hz rhythm is observed in several sensory region in the brain. In visual related region of occipital, we call to alpha rhythm, and auditory related region of temporal call to tau rhythm, sensorimotor related region of parietal call to mu rhythm. These rhythms are decreased in task related region and increased in task irrelevant regions. This means that these rhythms play a pivotal role of inhibition in task irrelevant region. It may be helpful to attention to the task. In several literature about the alpha-band inhibition in multi-sensory modality experiment, they observed this effect in the occipital and somatosensory region. In this study, we hypothesized that we can also observe the alpha-band inhibition in the auditory cortex, mediated by the tau rhythm. Before that, we first investigated the existence of the alpha and tau rhythm in occipital and temporal region, respectively. To see these rhythms, we applied the visual and auditory stimulation, in turns, suppressed in task relevant regions, respectively.

  1. Measurement of the occipital alpha rhythm and temporal tau rhythm by using magnetoencephalography

    International Nuclear Information System (INIS)

    Kim, J. E.; Gohel, Bakul; Kim, K.; Kwon, H.; An, Kyung Min

    2015-01-01

    Developing Magnetoencephalography (MEG) based on Superconducting Quantum Interference Device (SQUID) facilitates to observe the human brain functions in non-invasively and high temporal and high spatial resolution. By using this MEG, we studied alpha rhythm (8-13 Hz) that is one of the most predominant spontaneous rhythm in human brain. The 8–13 Hz rhythm is observed in several sensory region in the brain. In visual related region of occipital, we call to alpha rhythm, and auditory related region of temporal call to tau rhythm, sensorimotor related region of parietal call to mu rhythm. These rhythms are decreased in task related region and increased in task irrelevant regions. This means that these rhythms play a pivotal role of inhibition in task irrelevant region. It may be helpful to attention to the task. In several literature about the alpha-band inhibition in multi-sensory modality experiment, they observed this effect in the occipital and somatosensory region. In this study, we hypothesized that we can also observe the alpha-band inhibition in the auditory cortex, mediated by the tau rhythm. Before that, we first investigated the existence of the alpha and tau rhythm in occipital and temporal region, respectively. To see these rhythms, we applied the visual and auditory stimulation, in turns, suppressed in task relevant regions, respectively

  2. Circadian melatonin concentration rhythm is lost in pregnant women with altered blood pressure rhythm.

    Science.gov (United States)

    Tranquilli, A L; Turi, A; Giannubilo, S R; Garbati, E

    2004-03-01

    We assessed the correlation between the rhythm of melatonin concentration and circadian blood pressure patterns in normal and hypertensive pregnancy. Ambulatory 24-h blood pressure and blood samples every 4 h were monitored in 16 primigravidae who had shown an abnormal circadian blood pressure pattern (eight pre-eclamptic and eight normotensive) in pregnancy and 6-12 months after pregnancy. The circadian rhythm was analyzed by chronobiological measures. Eight normotensive women with maintained blood pressure rhythm served as controls. During pregnancy, melatonin concentration was significantly higher in pre-eclamptic than in normotensive women (pre-eclampsia, 29.4 +/- 1.9 pg/ml, normotensin, altered rhythm, 15.6 +/- 2.1; controls, 22.7 +/- 1.8; p lost in all pregnant women with loss of blood pressure rhythm. After pregnancy, normotensive women showed a reappearance of both melatonin and blood pressure rhythm, whereas pre-eclamptic women showed a reappearance of blood pressure but not melatonin rhythm. The loss of blood pressure rhythm in pregnancy is consistent with the loss of melatonin concentration rhythm. In pre-eclamptic women, the normalization of blood pressure rhythm, while melatonin rhythm remained altered, suggests a temporal or causal priority of circadian concentration of melatonin in the determination of blood pressure trend.

  3. Heart rate patterns during courtship and mating in rams and in estrous and nonestrous ewes ().

    Science.gov (United States)

    Orihuela, A; Omaña, J C; Ungerfeld, R

    2016-02-01

    The aim of this study was to compare the heart rate (HR) patterns in rams mated with estrous or nonestrous ewes and in mated estrous and nonestrous ewes () during courtship and mating. For this purpose, HR and behavior were recorded using a radio telemetry recording system and a closed-circuit television system with video recording, respectively. Rams were joined with either an estrous ( = 10) or a nonestrous ( = 10) ewe that was restrained in a stanchion by the neck. Data were continuously recorded until each ram performed 3 ejaculations. Eight days later, the HR of the 10 estrous and 10 nonestrous ewes was recorded during mating. Although the time between entrance into the yard and the first ejaculation was similar across rams, rams that mounted estrous ewes were faster at attaining their second (3min5s ± 17 s vs. 5min28s ± 18 s) and third (7min58s ± 45 s vs. 12 min ± 1min14s) ejaculations (all ewes. In all cases, HR reached maximum values immediately after each ejaculation and the HR pattern was similar across ejaculations (first, second, and third). Although HR was similar between estrous and nonestrous ewes before mating, nonestrous ewes had higher HR ( ewes displayed shorter interejaculation periods but HR did not differ between groups of rams during any ejaculation (first, second, or third), 2) HR for both groups of rams peaked shortly after each ejaculation, and 3) HR increased more in nonestrous than in estrous ewes while mating.

  4. Methyltestosterone-induced changes in electro-olfactogram responses and courtship behaviors of cyprinids.

    Science.gov (United States)

    Belanger, Rachelle M; Pachkowski, Melanie D; Stacey, Norm E

    2010-01-01

    In the tinfoil barb (Barbonymus schwanenfeldii; family Cyprinidae), we previously found that increased olfactory sensitivity to a female prostaglandin pheromone could induce sexual behavior display in juvenile fish treated with androgens. Here, we determined if this phenomenon is widespread among cyprinid fishes by adding 17alpha-methyltestosterone (MT) to aquaria containing juveniles of 4 cyprinid species (tinfoil barbs; redtail sharkminnows, Epalzeorhynchos bicolor; goldfish, Carassius auratus; zebrafish, Danio rerio) and then using electro-olfactogram (EOG) recordings and behavioral assays to determine if androgen treatment enhances pheromone detection and male sex behaviors. In all 4 cyprinids, MT treatment increased the magnitudes and sensitivities of EOG response to prostaglandins and, consistent with our initial study on tinfoil barbs, did not affect EOG responses to the free and conjugated steroid to which each species is most sensitive. In zebrafish, EOG responses to prostaglandins were similar in MT-treated juveniles and adult males, whereas responses of control (ethanol exposed) fish were similar to those of adult females. Finally, as previously observed in tinfoil barbs, MT treatment of juvenile redtail sharkminnows increased courtship behaviors (nuzzling and quivering) with a stimulus fish. We conclude that androgen-induced increase in olfactory responsiveness to pheromonal prostaglandins is common among the family Cyprinidae. This phenomenon will help us unravel the development of sexually dimorphic olfactory-mediated behavior.

  5. [Courtship behavior, communicative sound production and resistance to stress in Drosophila mutants with defective agnostic gene, coding for LIMK1].

    Science.gov (United States)

    Popov, A V; Kaminskaia, A N; Savvateeva-Popova, E V

    2009-01-01

    To elucidate the role of one of the main elements of signal cascade of actin remodeling--LIM-kinase 1 (LIMK1)--in the control of animal behavior we studied the characteristics of courtship behavior, parameters of acoustic communicative signals and their resistance to heat shock (HS, 37 degrees C, 30 min) in Drosophila melanogaster males from the strain with mutation in locus agnostic (agn(ts3)) containing gene CG1848 for LIMK1. The data obtained was compared with the results of our previous similar investigation on wild type CS males (Popov et al., 2006). Flies were divided into 4 groups. The males of control groups were not subjected to heat shock. The rest of males were subjected to heat shock either at the beginning of larval development when predominantly mushroom body neuroblasts are dividing (groups HS1), or at the prepupal stage when the brain central complex is developing (groups HS2), or at the imago stage one hour before the test (groups HS3). All males were tested at the age of 5 days. Virgin and fertilized CS females were used as courtship objects. Comparison of control groups of the two strains--CS and agnostic--have shown that the mutation agn(ts3) has no influence on the main parameters of courtship behavior of intact (not subjected to HS) males (courtship latency, the rapidity of achieving copulation, courtship efficiency) but leads to lowering of their sexual activity, increase of duration of sound trains in the songs and to slight increase of rate and stability of working of singing pacemakers. Agnostic males in comparison to wild type males are more resistant to HS given 1 hour before the test. After HS their courtship intensity does not decrease and the main parameters of their courtship behavior and communicative sound signals in comparison tu wild type males either do not change, or appear to be even better stabilized. The frequency of distorted sound pulses (an indicator of frequency of impairments in the activity pattern of neuro

  6. Fluctuation of biological rhythm in finger tapping

    Science.gov (United States)

    Yoshinaga, H.; Miyazima, S.; Mitake, S.

    2000-06-01

    By analyzing biological rhythms obtained from finger tapping, we have investigated the differences of two biological rhythms between healthy and handicapped persons caused by Parkinson, brain infraction, car accident and so on. In this study, we have observed the motion of handedness of all subjects and obtained a slope a which characterizes a power-law relation between frequency and amplitude of finger-tapping rhythm. From our results, we have estimated that the slope a=0.06 is a rough criterion in order to distinguish healthy and handicapped persons.

  7. Circadian Rhythm Management System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The value of measuring sleep-wake cycles is significantly enhanced by measuring other physiological signals that depend on circadian rhythms (such as heart rate and...

  8. Fixed differences in the paralytic gene define two lineages within the Lutzomyia longipalpis complex producing different types of courtship songs.

    Directory of Open Access Journals (Sweden)

    Rachel M M A Lins

    Full Text Available The sand fly Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae, the most important vector of American visceral leishmaniasis, is widely distributed in Latin America. There is currently a consensus that it represents a species complex, however, the number and distribution of the different siblings is still uncertain. Previous analyses have indicated that Brazilian populations of this vector can be divided into two main groups according to the type of courtship song (Burst vs. Pulse males produce during copulation. Nevertheless, no diagnostic differences have been observed between these two groups with most molecular markers used to date. We analyzed the molecular divergence in a fragment of the paralytic (para gene, a locus involved in the control of courtship songs in Drosophila, among a number of Lu. longipalpis populations from Brazil producing Burst and Pulse-type songs. Our results revealed a very high level of divergence and fixed differences between populations producing the two types of songs. We also compared Lu. longipalpis with a very closely related species, Lutzomyia cruzi, which produces Burst-type songs. The results indicated a higher number of fixed differences between Lu. cruzi and the Pulse-type populations of Lu. longipalpis than with those producing Burst-type songs. The data confirmed our previous assumptions that the presence of different sibling species of the Lu. longipalpis complex in Brazil can be divided into two main groups, one representing a single species and a second more heterogeneous group that probably represents a number of incipient species. We hypothesize that para might be one of the genes directly involved in the control of the courtship song differences between these two groups or that it is linked to other loci associated with reproductive isolation of the Brazilian species.

  9. Fixed Differences in the paralytic Gene Define Two Lineages within the Lutzomyia longipalpis Complex Producing Different Types of Courtship Songs

    Science.gov (United States)

    Lins, Rachel M. M. A.; Souza, Nataly A.; Brazil, Reginaldo P.; Maingon, Rhayza D. C.; Peixoto, Alexandre A.

    2012-01-01

    The sand fly Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae), the most important vector of American visceral leishmaniasis, is widely distributed in Latin America. There is currently a consensus that it represents a species complex, however, the number and distribution of the different siblings is still uncertain. Previous analyses have indicated that Brazilian populations of this vector can be divided into two main groups according to the type of courtship song (Burst vs. Pulse) males produce during copulation. Nevertheless, no diagnostic differences have been observed between these two groups with most molecular markers used to date. We analyzed the molecular divergence in a fragment of the paralytic (para) gene, a locus involved in the control of courtship songs in Drosophila, among a number of Lu. longipalpis populations from Brazil producing Burst and Pulse-type songs. Our results revealed a very high level of divergence and fixed differences between populations producing the two types of songs. We also compared Lu. longipalpis with a very closely related species, Lutzomyia cruzi, which produces Burst-type songs. The results indicated a higher number of fixed differences between Lu. cruzi and the Pulse-type populations of Lu. longipalpis than with those producing Burst-type songs. The data confirmed our previous assumptions that the presence of different sibling species of the Lu. longipalpis complex in Brazil can be divided into two main groups, one representing a single species and a second more heterogeneous group that probably represents a number of incipient species. We hypothesize that para might be one of the genes directly involved in the control of the courtship song differences between these two groups or that it is linked to other loci associated with reproductive isolation of the Brazilian species. PMID:22970200

  10. Dysrhythmia: a specific congenital rhythm perception deficit

    Directory of Open Access Journals (Sweden)

    Jacques eLaunay

    2014-02-01

    Full Text Available Why do some people have problems ‘feeling the beat’? Here we investigate participants with congenital impairments in musical rhythm perception and production. A web-based version of the Montreal Battery of Evaluation of Amusia (MBEA was used to screen for difficulties with rhythmic processing in a large sample and we identified three ‘dysrhythmic’ individuals who scored below cut-off for the rhythm subtest, but not the pitch-based subtests. Follow-up testing in the laboratory was conducted to characterize the nature of both rhythm perception and production deficits in these dysrhythmic individuals. We found that they differed from control participants when required to synchronize their tapping to an external stimulus with a metrical pulse, but not when required to tap spontaneously (with no external stimulus or to tap in time to an isochronous stimulus. Dysrhythmics exhibited a general tendency to tap at half the expected tempo when asked to synchronize to the beat of strongly metrical rhythms. These results suggest that the individuals studied here did not have motor production problems, but suffer from a selective rhythm perception deficit that influences the ability to entrain to metrical rhythms.

  11. The role of feeding rhythm, adrenal hormones and neuronal inputs in synchronizing daily clock gene rhythms in the liver.

    Science.gov (United States)

    Su, Yan; Cailotto, Cathy; Foppen, Ewout; Jansen, Remi; Zhang, Zhi; Buijs, Ruud; Fliers, Eric; Kalsbeek, Andries

    2016-02-15

    The master clock in the hypothalamic suprachiasmatic nucleus (SCN) is assumed to distribute rhythmic information to the periphery via neural, humoral and/or behavioral connections. Until now, feeding, corticosterone and neural inputs are considered important signals for synchronizing daily rhythms in the liver. In this study, we investigated the necessity of neural inputs as well as of the feeding and adrenal hormone rhythms for maintaining daily hepatic clock gene rhythms. Clock genes kept their daily rhythm when only one of these three signals was disrupted, or when we disrupted hepatic neuronal inputs together with the adrenal hormone rhythm or with the daily feeding rhythm. However, all clock genes studied lost their daily expression rhythm after simultaneous disruption of the feeding and adrenal hormone rhythm. These data indicate that either a daily rhythm of feeding or adrenal hormones should be present to synchronize clock gene rhythms in the liver with the SCN. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  12. Timing of host feeding drives rhythms in parasite replication

    KAUST Repository

    Prior, Kimberley F.

    2018-02-26

    Circadian rhythms enable organisms to synchronise the processes underpinning survival and reproduction to anticipate daily changes in the external environment. Recent work shows that daily (circadian) rhythms also enable parasites to maximise fitness in the context of ecological interactions with their hosts. Because parasite rhythms matter for their fitness, understanding how they are regulated could lead to innovative ways to reduce the severity and spread of diseases. Here, we examine how host circadian rhythms influence rhythms in the asexual replication of malaria parasites. Asexual replication is responsible for the severity of malaria and fuels transmission of the disease, yet, how parasite rhythms are driven remains a mystery. We perturbed feeding rhythms of hosts by 12 hours (i.e. diurnal feeding in nocturnal mice) to desynchronise the host’s peripheral oscillators from the central, light-entrained oscillator in the brain and their rhythmic outputs. We demonstrate that the rhythms of rodent malaria parasites in day-fed hosts become inverted relative to the rhythms of parasites in night-fed hosts. Our results reveal that the host’s peripheral rhythms (associated with the timing of feeding and metabolism), but not rhythms driven by the central, light-entrained circadian oscillator in the brain, determine the timing (phase) of parasite rhythms. Further investigation reveals that parasite rhythms correlate closely with blood glucose rhythms. In addition, we show that parasite rhythms resynchronise to the altered host feeding rhythms when food availability is shifted, which is not mediated through rhythms in the host immune system. Our observations suggest that parasites actively control their developmental rhythms. Finally, counter to expectation, the severity of disease symptoms expressed by hosts was not affected by desynchronisation of their central and peripheral rhythms. Our study at the intersection of disease ecology and chronobiology opens up a new

  13. Timing of host feeding drives rhythms in parasite replication

    KAUST Repository

    Prior, Kimberley F

    2017-12-07

    Circadian rhythms enable organisms to synchronise the processes underpinning survival and reproduction to anticipate daily changes in the external environment. Recent work shows that daily (circadian) rhythms also enable parasites to maximise fitness in the context of ecological interactions with their hosts. Because parasite rhythms matter for their fitness, understanding how they are regulated could lead to innovative ways to reduce the severity and spread of diseases. Here, we examine how host circadian rhythms influence rhythms in the asexual replication of malaria parasites. Asexual replication is responsible for the severity of malaria and fuels transmission of the disease, yet, how parasite rhythms are driven remains a mystery. We perturbed feeding rhythms of hosts by 12 hours (i.e. diurnal feeding in nocturnal mice) to desynchronise the host\\'s peripheral oscillators from the central, light-entrained oscillator in the brain and their rhythmic outputs. We demonstrate that the rhythms of rodent malaria parasites in day-fed hosts become inverted relative to the rhythms of parasites in night-fed hosts. Our results reveal that the host\\'s peripheral rhythms (associated with the timing of feeding and metabolism), but not rhythms driven by the central, light-entrained circadian oscillator in the brain, determine the timing (phase) of parasite rhythms. Further investigation reveals that parasite rhythms correlate closely with blood glucose rhythms. In addition, we show that parasite rhythms resynchronise to the altered host feeding rhythms when food availability is shifted, which is not mediated through rhythms in the host immune system. Our observations suggest that parasites actively control their developmental rhythms. Finally, counter to expectation, the severity of disease symptoms expressed by hosts was not affected by desynchronisation of their central and peripheral rhythms. Our study at the intersection of disease ecology and chronobiology opens up a new

  14. Possible hormonal interaction for eliciting courtship behavior in the male newt, Cynops pyrrhogaster.

    Science.gov (United States)

    Toyoda, Fumiyo; Hasunuma, Itaru; Nakada, Tomoaki; Haraguchi, Shogo; Tsutsui, Kazuyoshi; Kikuyama, Sakae

    2015-12-01

    Reproductive behavior in amphibians, as in other vertebrate animals, is under the control of multiple hormonal substances. Prolactin (PRL), arginine vasotocin (AVT), androgen, and 7α-hydroxypregnenolone (7α-OH PREG), four such substances with hormonal activity, are known to be involved in the expression of the tail vibration behavior which is the initial step of courtship performed by the male newt, Cynops pyrrhogaster. As current information on the interaction(s) between these hormones in terms of eliciting tail vibration behavior is limited, we have investigated whether the decline of expression of tail vibration behavior due to suppression of the activity of any one of these hormones can be restored by supplying any one of the other three hormones exogenously. Expression of the behavior was determined in terms of incidence (% of test animals exhibiting the behavior) and frequency (number of times that the behavior was repeated during the test period). Neither PRL nor androgen restored the decline in the incidence and frequency of the tail vibration behavior caused by the suppression of the activity of any one of other three hormones. AVT completely restored both the anti-PRL antibody-induced and flutamide (an androgen receptor antagonist)-induced, but not ketoconazole (an inhibitor of the steroidogenic CYP enzymes)-induced decline in the incidence and frequency of the tail vibration behavior. The neurosteroid, 7α-OH PREG, failed to restore flutamide-induced decline in the incidence and frequency of the behavior. However, it was able to restore both anti-PRL antibody-induced and AVT receptor antagonist-induced decline in the incidence, but not in the frequency of the behavior. In another experiment designed to see the activity of hormones enhancing the frequency of the tail vibration behavior, AVT was revealed to be more potent than 7α-OH PREG. The role of each hormonal substance in determining the expression of the tail vibration behavior was discussed based

  15. Evaluation of the courtship and of the hybrid male sterility among Drosophila buzzatii cluster species (Diptera, Drosophilidae

    Directory of Open Access Journals (Sweden)

    MACHADO L. P. de B.

    2002-01-01

    Full Text Available In the Drosophila repleta group the establishment of subgroups and complexes made on the basis of morphological and cytological evidences is supported by tests of reproductive isolation. Among species in the repleta group, the buzzatii cluster, due to its polymorphism and polytipism, is an excellent material for ecological and speciation studies. Some interspecific crosses involving Drosophila seriema, Drosophila sp. B, D. koepferae and D. buzzatii strains were completely sterile while others involving strains from these species produced F1 hybrids that did not yield F2. In the present work, data on courtship duration and copula occurrence obtained in the analysis of flies from parental sterile crosses and on spermatozoon mobility observed in F1 hybrids that did not yield F2 are presented. Copula did not occur during one hour of observation and the spermatozoon also did not show mobility at any of the analyzed stages (3, 7, 9 and 10 days old. There was a high variation in courtship average duration and in the percentage of males that courted the females. The reproductive isolation mechanisms indicated by these observations were pre and post-zygotic, as supported by the absence of copula and male sterility. Data obtained also showed the occurrence of different degrees of reproductive compatibility among the strains classified as the same species but from distinct geographic localities.

  16. Signal complexity and modular organization of the courtship behaviours of two sibling species of wolf spiders (Araneae: Lycosidae).

    Science.gov (United States)

    Chiarle, Alberto; Isaia, Marco

    2013-07-01

    In this study, we compare the courtship behaviours of Pardosa proxima and P. vlijmi, two species of wolf spiders up to now regarded as "ethospecies", by means of motion analysis methodologies. In particular, we investigate the features of the signals, aiming at understanding the evolution of the courtship and its role in species delimitation and speciation processes. In our model, we highlight a modular structure of the behaviours and the presence of recurring units and phases. According to other similar cases concerning animal communication, we observed one highly variable and one stereotyped phase for both species. The stereotyped phase is here regarded as a signal related to species identity or an honest signal linked directly to the quality of the signaler. On the contrary, the variable phase aims to facilitate signal detection and assessment by the female reducing choice costs or errors. Variable phases include cues arisen from Fisherian runaway selection, female sensory exploitation and remaining of past selections. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Two distinct genomic regions, harbouring the period and fruitless genes, affect male courtship song in Drosophila montana.

    Science.gov (United States)

    Lagisz, M; Wen, S-Y; Routtu, J; Klappert, K; Mazzi, D; Morales-Hojas, R; Schäfer, M A; Vieira, J; Hoikkala, A; Ritchie, M G; Butlin, R K

    2012-06-01

    Acoustic signals often have a significant role in pair formation and in species recognition. Determining the genetic basis of signal divergence will help to understand signal evolution by sexual selection and its role in the speciation process. An earlier study investigated quantitative trait locus for male courtship song carrier frequency (FRE) in Drosophila montana using microsatellite markers. We refined this study by adding to the linkage map markers for 10 candidate genes known to affect song production in Drosophila melanogaster. We also extended the analyses to additional song characters (pulse train length (PTL), pulse number (PN), interpulse interval, pulse length (PL) and cycle number (CN)). Our results indicate that loci in two different regions of the genome control distinct features of the courtship song. Pulse train traits (PTL and PN) mapped to the X chromosome, showing significant linkage with the period gene. In contrast, characters related to song pulse properties (PL, CN and carrier FRE) mapped to the region of chromosome 2 near the candidate gene fruitless, identifying these genes as suitable loci for further investigations. In previous studies, the pulse train traits have been found to vary substantially between Drosophila species, and so are potential species recognition signals, while the pulse traits may be more important in intra-specific mate choice.

  18. Evaluation of the courtship and of the hybrid male sterility among Drosophila buzzatii cluster species (Diptera, Drosophilidae).

    Science.gov (United States)

    Machado, L P; Castro, J P; Madi-Ravazzi, L

    2002-11-01

    In the Drosophila repleta group the establishment of subgroups and complexes made on the basis of morphological and cytological evidences is supported by tests of reproductive isolation. Among species in the repleta group, the buzzatii cluster, due to its polymorphism and polytipism, is an excellent material for ecological and speciation studies. Some interspecific crosses involving Drosophila seriema, Drosophila sp. B, D. koepferae and D. buzzatii strains were completely sterile while others involving strains from these species produced F1 hybrids that did not yield F2. In the present work, data on courtship duration and copula occurrence obtained in the analysis of flies from parental sterile crosses and on spermatozoon mobility observed in F1 hybrids that did not yield F2 are presented. Copula did not occur during one hour of observation and the spermatozoon also did not show mobility at any of the analyzed stages (3, 7, 9 and 10 days old). There was a high variation in courtship average duration and in the percentage of males that courted the females. The reproductive isolation mechanisms indicated by these observations were pre and post-zygotic, as supported by the absence of copula and male sterility. Data obtained also showed the occurrence of different degrees of reproductive compatibility among the strains classified as the same species but from distinct geographic localities.

  19. Mu rhythm desynchronization by tongue thrust observation

    Directory of Open Access Journals (Sweden)

    Kotoe eSakihara

    2015-09-01

    Full Text Available We aimed to investigate the mu rhythm in the sensorimotor area during tongue thrust observation and to obtain an answer to the question as to how subtle non-verbal orofacial movement observation activates the sensorimotor area. Ten healthy volunteers performed finger tap execution, tongue thrust execution, and tongue thrust observation. The electroencephalogram was recorded from 128 electrodes placed on the scalp, and regions of interest were set at sensorimotor areas. The event-related desynchronization (ERD and event-related synchronization (ERS for the mu rhythm (8–13 Hz and beta (13−25 Hz bands were measured. Tongue thrust observation induced mu rhythm ERD, and the ERD was detected at the left hemisphere regardless whether the observed tongue thrust was toward the left or right. Mu rhythm ERD was also recorded during tongue thrust execution. However, temporal analysis revealed that the ERD associated with tongue thrust observation preceded that associated with execution by approximately 2 s. Tongue thrust observation induces mu rhythm ERD in sensorimotor cortex with left hemispheric dominance.

  20. Circadian Rhythm Disruption Promotes Lung Tumorigenesis.

    Science.gov (United States)

    Papagiannakopoulos, Thales; Bauer, Matthew R; Davidson, Shawn M; Heimann, Megan; Subbaraj, Lakshmipriya; Bhutkar, Arjun; Bartlebaugh, Jordan; Vander Heiden, Matthew G; Jacks, Tyler

    2016-08-09

    Circadian rhythms are 24-hr oscillations that control a variety of biological processes in living systems, including two hallmarks of cancer, cell division and metabolism. Circadian rhythm disruption by shift work is associated with greater risk for cancer development and poor prognosis, suggesting a putative tumor-suppressive role for circadian rhythm homeostasis. Using a genetically engineered mouse model of lung adenocarcinoma, we have characterized the effects of circadian rhythm disruption on lung tumorigenesis. We demonstrate that both physiologic perturbation (jet lag) and genetic mutation of the central circadian clock components decreased survival and promoted lung tumor growth and progression. The core circadian genes Per2 and Bmal1 were shown to have cell-autonomous tumor-suppressive roles in transformation and lung tumor progression. Loss of the central clock components led to increased c-Myc expression, enhanced proliferation, and metabolic dysregulation. Our findings demonstrate that both systemic and somatic disruption of circadian rhythms contribute to cancer progression. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. [Dynamic Attending Binds Time and Rhythm Perception].

    Science.gov (United States)

    Kuroda, Tsuyoshi; Ono, Fuminori; Kadota, Hiroshi

    2017-11-01

    Relations between time and rhythm perception are discussed in this review of psychophysical research relevant to the multiple-look effect and dynamic-attending theory. Discrimination of two neighboring intervals that are marked by three successive sounds is improved when the presentation of the first (standard, S) interval is repeated before that of the second (comparison, C), as SSSSC. This improvement in sensitivity, called the multiple-look effect, occurs because listeners (1) perceive regular rhythm during the repetition of the standard interval, (2) predict the timing of subsequent sounds, and (3) detect sounds that are deviated from the predicted timing. The dynamic-attending theory attributes such predictions to the entrainment of attentional rhythms. An endogenous attentional rhythm is synchronized with the periodic succession of sounds marking the repeated standard. The standard and the comparison are discriminated on the basis of whether the ending marker of the comparison appears at the peak of the entrained attentional rhythm. This theory is compatible with the findings of recent neurophysiological studies that relate temporal prediction to neural oscillations.

  2. Daily Rhythms in Mobile Telephone Communication.

    Science.gov (United States)

    Aledavood, Talayeh; López, Eduardo; Roberts, Sam G B; Reed-Tsochas, Felix; Moro, Esteban; Dunbar, Robin I M; Saramäki, Jari

    2015-01-01

    Circadian rhythms are known to be important drivers of human activity and the recent availability of electronic records of human behaviour has provided fine-grained data of temporal patterns of activity on a large scale. Further, questionnaire studies have identified important individual differences in circadian rhythms, with people broadly categorised into morning-like or evening-like individuals. However, little is known about the social aspects of these circadian rhythms, or how they vary across individuals. In this study we use a unique 18-month dataset that combines mobile phone calls and questionnaire data to examine individual differences in the daily rhythms of mobile phone activity. We demonstrate clear individual differences in daily patterns of phone calls, and show that these individual differences are persistent despite a high degree of turnover in the individuals' social networks. Further, women's calls were longer than men's calls, especially during the evening and at night, and these calls were typically focused on a small number of emotionally intense relationships. These results demonstrate that individual differences in circadian rhythms are not just related to broad patterns of morningness and eveningness, but have a strong social component, in directing phone calls to specific individuals at specific times of day.

  3. Daily rhythm of cerebral blood flow velocity

    Directory of Open Access Journals (Sweden)

    Spielman Arthur J

    2005-03-01

    Full Text Available Abstract Background CBFV (cerebral blood flow velocity is lower in the morning than in the afternoon and evening. Two hypotheses have been proposed to explain the time of day changes in CBFV: 1 CBFV changes are due to sleep-associated processes or 2 time of day changes in CBFV are due to an endogenous circadian rhythm independent of sleep. The aim of this study was to examine CBFV over 30 hours of sustained wakefulness to determine whether CBFV exhibits fluctuations associated with time of day. Methods Eleven subjects underwent a modified constant routine protocol. CBFV from the middle cerebral artery was monitored by chronic recording of Transcranial Doppler (TCD ultrasonography. Other variables included core body temperature (CBT, end-tidal carbon dioxide (EtCO2, blood pressure, and heart rate. Salivary dim light melatonin onset (DLMO served as a measure of endogenous circadian phase position. Results A non-linear multiple regression, cosine fit analysis revealed that both the CBT and CBFV rhythm fit a 24 hour rhythm (R2 = 0.62 and R2 = 0.68, respectively. Circadian phase position of CBT occurred at 6:05 am while CBFV occurred at 12:02 pm, revealing a six hour, or 90 degree difference between these two rhythms (t = 4.9, df = 10, p Conclusion In conclusion, time of day variations in CBFV have an approximately 24 hour rhythm under constant conditions, suggesting regulation by a circadian oscillator. The 90 degree-phase angle difference between the CBT and CBFV rhythms may help explain previous findings of lower CBFV values in the morning. The phase difference occurs at a time period during which cognitive performance decrements have been observed and when both cardiovascular and cerebrovascular events occur more frequently. The mechanisms underlying this phase angle difference require further exploration.

  4. Differential courtship activity and alterations of reproductive success of competing gupply males as an indicator for low concentrations of aquatic pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, J.H.; Peters, K.

    1988-09-01

    Differential courtship activity of guppy males competing for the same females was used as a bioindicator for low concentrations of water-borne pollutants in a previous study. Patterns of male sexual activity were chosen because they determine reproductive success. The mean difference between courtship activities of two male competitors determines the relative fitness of the male in question. Accordingly, the decrease in mean differential courtship after exposure to aquatic contaminants was predicted to cause a corresponding change in the relative reproductive success. The present study completed the previous one by repeating the experiment with a 10% addition of wastewater drawn from the last clearing basin of a Munich purification plant this time using virgin (non-inseminated) females which were receptive to male courtship. The females subsequently were allowed to produce as many offspring as possible. The number of young guppies sired by individual male competitors could easily be traced by the use of sex-linked phenotypic color patterns as markers. The purpose of these two studies was to show that the quantification of sexual activities of male guppies is useful for monitoring environmental alterations which affect fitness characters.

  5. Circadian rhythm asynchrony in man during hypokinesis.

    Science.gov (United States)

    Winget, C. M.; Vernikos-Danellis, J.; Cronin, S. E.; Leach, C. S.; Rambaut, P. C.; Mack, P. B.

    1972-01-01

    Posture and exercise were investigated as synchronizers of certain physiologic rhythms in eight healthy male subjects in a defined environment. Four subjects exercised during bed rest. Body temperature (BT), heart rate, plasma thyroid hormone, and plasma steroid data were obtained from the subjects for a 6-day ambulatory equilibration period before bed rest, 56 days of bed rest, and a 10-day recovery period after bed rest. The results indicate that the mechanism regulating the circadian rhythmicity of the cardiovascular system is rigorously controlled and independent of the endocrine system, while the BT rhythm is more closely aligned to the endocrine system.

  6. Circadian Rhythm Sleep-Wake Disorders.

    Science.gov (United States)

    Abbott, Sabra M; Reid, Kathryn J; Zee, Phyllis C

    2015-12-01

    The circadian system regulates the timing and expression of nearly all biological processes, most notably, the sleep-wake cycle, and disruption of this system can result in adverse effects on both physical and mental health. The circadian rhythm sleep-wake disorders (CRSWDs) consist of 5 disorders that are due primarily to pathology of the circadian clock or to a misalignment of the timing of the endogenous circadian rhythm with the environment. This article outlines the nature of these disorders, the association of many of these disorders with psychiatric illness, and available treatment options. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Circadian rhythm in idiopathic normal pressure hydrocephalus.

    Science.gov (United States)

    Eleftheriou, Andreas; Ulander, Martin; Lundin, Fredrik

    2018-01-01

    The pathogenesis of idiopathic normal pressure hydrocephalus (iNPH) takes place in structures close to the cerebral ventricular system. Suprachiasmatic nucleus (SCN), situated close to the third ventricle, is involved in circadian rhythm. Diurnal disturbances are well-known in demented patients. The cognitive decline in iNPH is potentially reversible after a shunt operation. Diurnal rhythm has never been studied in iNPH. We hypothesize that there is a disturbance of circadian rhythm in iNPH-patients and the aim was to study any changes of the diurnal rhythm (mesor and circadian period) as well as any changes of the diurnal amplitude and acrophase of the activity in iNPH-patients before and after a shunt operation. Twenty consecutive iNPH-patients fulfilling the criteria of the American iNPH-guidelines, 9 males and 11 females, mean age 73 (49-81) years were included. The patients underwent a pre-operative clinical work-up including 10m walk time (w10mt) steps (w10ms), TUG-time (TUGt) and steps (TUGs) and for cognitive function an MMSE score was measured. In order to receive circadian rhythm data actigraphic recordings were performed using the SenseWear 2 (BodyMedia Inc Pittsburgh, PA, USA) actigraph. Cosinor analyses of accelerometry data were performed in "R" using non-linear regression with Levenburg- Marquardt estimation. Pre- and post-operative data regarding mesor, amplitude and circadian period were compared using Wilcoxon-Mann-Whitney test for paired data. Twenty patients were evaluated before and three month post-operatively. Motor function (w10mt, w10ms, TUGt, TUGs) was significantly improved while MMSE was not significantly changed. Actigraphic measurements (mesor, amplitude and circadian period) showed no significant changes after shunt operation. This is the first systematic study of circadian rhythm in iNPH-patients. We found no significant changes in circadian rhythm after shunt surgery. The conceptual idea of diurnal rhythm changes in hydrocephalus is

  8. Circadian rhythm and sleep influences on digestive physiology and disorders

    OpenAIRE

    Vaughn, Bradley; Rotolo,Sean; Roth,Heidi

    2014-01-01

    Bradley V Vaughn, Sean Rotolo, Heidi L Roth Division of Sleep Medicine, Department of Neurology, University of North Carolina School of Medicine, Chapel Hill, NC, USA Abstract: Circadian rhythms and sleep influence a variety of physiological functions, including the digestive system. The digestive system also has intrinsic rhythms that interact dynamically with circadian rhythms. New advances in understanding the interaction of these rhythms and sleep provide the prospect of evaluating their...

  9. Monkey Lipsmacking Develops Like the Human Speech Rhythm

    Science.gov (United States)

    Morrill, Ryan J.; Paukner, Annika; Ferrari, Pier F.; Ghazanfar, Asif A.

    2012-01-01

    Across all languages studied to date, audiovisual speech exhibits a consistent rhythmic structure. This rhythm is critical to speech perception. Some have suggested that the speech rhythm evolved "de novo" in humans. An alternative account--the one we explored here--is that the rhythm of speech evolved through the modification of rhythmic facial…

  10. EFFECTS OF CIRCADIAN RHYTHM ON BALANCE PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Karagul Osman

    2017-09-01

    Full Text Available Introduction. The aim of the study was to examine the effect of circadian rhythm on dynamic balance performance and to determine the role of physical activity level, body temperature, chronotype, and gender in this possible effect. Material and

  11. Working night shifts affects surgeons' biological rhythm

    DEFF Research Database (Denmark)

    Amirian, Ilda; Andersen, Lærke T; Rosenberg, Jacob

    2015-01-01

    BACKGROUND: Chronic sleep deprivation combined with work during the night is known to affect performance and compromise residents' own safety. The aim of this study was to examine markers of circadian rhythm and the sleep-wake cycle in surgeons working night shifts. METHODS: Surgeons were monitor...

  12. Egg-laying rhythm in Drosophila melanogaster

    Indian Academy of Sciences (India)

    2008-12-31

    Dec 31, 2008 ... production of oocytes to egg-laying on selected sites (Alle- mand 1976b; Yang et al. .... (vii) Is the egg-laying rhythm regulated by hormones? .... were shown to be induced by factors synthesized in the re- productive tract of the ...

  13. RNAi of the circadian clock gene period disrupts the circadian rhythm but not the circatidal rhythm in the mangrove cricket

    OpenAIRE

    Takekata, Hiroki; Matsuura, Yu; Goto, Shin G.; Satoh, Aya; Numata, Hideharu

    2012-01-01

    The clock mechanism for circatidal rhythm has long been controversial, and its molecular basis is completely unknown. The mangrove cricket, Apteronemobius asahinai, shows two rhythms simultaneously in its locomotor activity: a circatidal rhythm producing active and inactive phases as well as a circadian rhythm modifying the activity intensity of circatidal active phases. The role of the clock gene period (per), one of the key components of the circadian clock in insects, was investigated in t...

  14. Biologic rhythms derived from Siberian mammoths' hairs.

    Directory of Open Access Journals (Sweden)

    Mike Spilde

    Full Text Available Hair is preserved for millennia in permafrost; it enshrines a record of biologic rhythms and offers a glimpse at chronobiology as it was in extinct animals. Here we compare biologic rhythms gleaned from mammoth's hairs with those of modern human hair. Four mammoths' hairs came from varying locations in Siberia 4600 km, four time zones, apart ranging in age between 18,000 and 20,000 years before present. We used two contemporaneous human hairs for comparison. Power spectra derived from hydrogen isotope ratios along the length of the hairs gave insight into biologic rhythms, which were different in the mammoths depending on location and differed from humans. Hair growth for mammoths was ∼31 cms/year and ∼16 cms/year for humans. Recurrent annual rhythms of slow and fast growth varying from 3.4 weeks/cycles to 8.7 weeks/cycles for slow periods and 1.2 weeks/cycles to 2.2 weeks/cycles for fast periods were identified in mammoth's hairs. The mineral content of mammoth's hairs was measured by electron microprobe analysis (k-ratios, which showed no differences in sulfur amongst the mammoth hairs but significantly more iron then in human hair. The fractal nature of the data derived from the hairs became evident in Mandelbrot sets derived from hydrogen isotope ratios, mineral content and geographic location. Confocal microscopy and scanning electron microscopy showed varied degrees of preservation of the cuticle largely independent of age but not location of the specimens. X-ray fluorescence microprobe and fluorescence computed micro-tomography analyses allowed evaluation of metal distribution and visualization of hollow tubes in the mammoth's hairs. Seasonal variations in iron and copper content combined with spectral analyses gave insights into variation in food intake of the animals. Biologic rhythms gleaned from power spectral plots obtained by modern methods revealed life style and behavior of extinct mega-fauna.

  15. Learning of courtship components in Drosophila mercatorum (Paterson & Wheller (Diptera, Drosophilidae Aprendizado de corte sexual em Drosophila mercatorum (Paterson & Wheller (Diptera, Drosophilidae

    Directory of Open Access Journals (Sweden)

    Andrei Polejack

    2007-03-01

    Full Text Available In Drosophila, courtship is an elaborate sequence of behavioural patterns that enables the flies to identify conspecific mates from those of closely related species. This is important because drosophilids usually gather in feeding sites, where males of various species court females vigorously. We investigated the effects of previous experience on D. mercatorum courtship, by testing if virgin males learn to improve their courtship by observing other flies (social learning, or by adjusting their pre-existent behaviour based on previous experiences (facilitation. Behaviours recorded in a controlled environment were courtship latency, courtship (orientation, tapping and wing vibration, mating and other behaviours not related to sexual activities. This study demonstrated that males of D. mercatorum were capable of improving their mating ability based on prior experiences, but they had no social learning on the development of courtship.Em Drosophila, a corte sexual consiste em uma elaborada seqüência de padrões comportamentais que possibilita às moscas reconhecer parceiros conspecíficos dentre indivíduos de outras espécies. Essa discriminação é importante uma vez que drosofilídeos geralmente se agregam em sítios de alimentação, onde machos de diversas espécies cortejam as fêmeas vigorosamente. Neste estudo, testamos se machos virgens aprimoram seu comportamento de corte mediante a observação do cortejo de outras moscas da população (aprendizado social, ou mediante experiências próprias anteriores (facilitação. O comportamento de corte das moscas, observado em ambiente controlado, foi registrado com relação aos seguintes componentes: latência da corte, duração da corte (orientação, "tapping" e vibração das asas, cópula, e outros comportamentos não relacionados à corte sexual. Os resultados aqui obtidos sugerem que machos de D. mercatorum são capazes de aprimorar sua habilidade de cortejar fêmeas em função de

  16. [Interpersonal and social rhythm therapy (IPSRT)].

    Science.gov (United States)

    Bottai, T; Biloa-Tang, M; Christophe, S; Dupuy, C; Jacquesy, L; Kochman, F; Meynard, J-A; Papeta, D; Rahioui, H; Adida, M; Fakra, E; Kaladjian, A; Pringuey, D; Azorin, J-M

    2010-12-01

    Bipolar disorder is common, recurrent, often severe and debiliting disorder. All types of bipolar disorder have a common determinant: depressive episode. It is justify to propose a psychotherapy which shown efficacy in depression. Howewer, perturbations in circadian rhythms have been implicated in the genesis of each episode of the illness. Biological circadian dysregulation can be encouraged by alteration of time-givers (Zeitgebers) or occurrence of time-disturbers (Zeitstörers). Addition of social rhythm therapy to interpersonal psychotherapy leads to create a new psychotherapy adaptated to bipolar disorders: InterPersonal and Social Rhythm Therapy (IPSRT). IPSRT, in combinaison with medication, has demonstrated efficacy as a treatment for bipolar disorders. IPSRT combines psychoeducation, behavioral strategy to regularize daily routines and interpersonal psychotherapy which help patients cope better with the multiple psychosocial and relationship problems associated with this chronic disorder. The main issues of this psychotherapy are: to take the history of the patient's illness and review of medication, to help patient for "grief for the lost healthy self" translated in the french version in "acceptance of a long-term medical condition", to give the sick role, to examinate the current relationships and changes proximal to the emergence of mood symptoms in the four problem areas (unresolved grief, interpersonal disputes, role transitions, role déficits), to examinate and increase daily routines and social rhythms. French version of IPSRT called TIPARS (with few differences), a time-limited psychotherapy, in 24 sessions during approximatively 6 months, is conducted in three phases. In the initial phase, the therapist takes a thorough history of previous episodes and their interpersonal context and a review of previous medication, provides psychoeducation, evaluates social rhythms, introduces the Social Rhythm Metric, identifies the patient's main interpersonal

  17. Sleep, circadian rhythms, and athletic performance.

    Science.gov (United States)

    Thun, Eirunn; Bjorvatn, Bjørn; Flo, Elisabeth; Harris, Anette; Pallesen, Ståle

    2015-10-01

    Sleep deprivation and time of day are both known to influence performance. A growing body of research has focused on how sleep and circadian rhythms impact athletic performance. This review provides a systematic overview of this research. We searched three different databases for articles on these issues and inspected relevant reference lists. In all, 113 articles met our inclusion criteria. The most robust result is that athletic performance seems to be best in the evening around the time when the core body temperature typically is at its peak. Sleep deprivation was negatively associated with performance whereas sleep extension seems to improve performance. The effects of desynchronization of circadian rhythms depend on the local time at which performance occurs. The review includes a discussion of differences regarding types of skills involved as well as methodological issues. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Regulation of reproduction by the circadian rhythms.

    Science.gov (United States)

    Zhang, Wen-Xiang; Chen, Si-Yu; Liu, Chang

    2016-12-25

    Mammals synchronize their circadian activity primarily to the cycles of light and darkness in the environment. Circadian rhythm is controlled by the central clock in the hypothalamic suprachiasmatic nucleus (SCN) and the peripheral clocks in various tissues. More importantly, the central clock can integrate photic/nonphotic signals to generate rhythmic outputs, and then drive the slave oscillators in peripheral tissues through neuroendocrine and behavioral signals. Human reproductive activities, as some other physiological functions, are controlled by the biological clocks. Accumulating lines of epidemiological and genetic evidence indicate that disruption of circadian clock can be directly involved in multiple pathological processes, including infertility. In this review, we mainly discuss the presence of a circadian clock in reproductive tissues and its roles in follicles development, ovulation, spermatogenesis, fertilization and embryo implantation, etc. As the increased shift work and assisted reproductive technologies possibly disrupt circadian rhythmicity to impact reproduction, the importance of circadian rhythms should be highlighted in the regulation of reproductive process.

  19. Clinical skills: cardiac rhythm recognition and monitoring.

    Science.gov (United States)

    Sharman, Joanna

    With technological advances, changes in provision of healthcare services and increasing pressure on critical care services, ward patients' severity of illness is ever increasing. As such, nurses need to develop their skills and knowledge to care for their client group. Competency in cardiac rhythm monitoring is beneficial to identify changes in cardiac status, assess response to treatment, diagnosis and post-surgical monitoring. This paper describes the basic anatomy and physiology of the heart and its conduction system, and explains a simple and easy to remember process of analysing cardiac rhythms (Resuscitation Council UK, 2000) that can be used in first-line assessment to assist healthcare practitioners in providing care to their patients.

  20. Circadian rhythms and obesity in mammals.

    Science.gov (United States)

    Froy, Oren

    2012-01-01

    Obesity has become a serious public health problem and a major risk factor for the development of illnesses, such as insulin resistance and hypertension. Attempts to understand the causes of obesity and develop new therapeutic strategies have mostly focused on caloric intake and energy expenditure. Recent studies have shown that the circadian clock controls energy homeostasis by regulating the circadian expression and/or activity of enzymes, hormones, and transport systems involved in metabolism. Moreover, disruption of circadian rhythms leads to obesity and metabolic disorders. Therefore, it is plausible that resetting of the circadian clock can be used as a new approach to attenuate obesity. Feeding regimens, such as restricted feeding (RF), calorie restriction (CR), and intermittent fasting (IF), provide a time cue and reset the circadian clock and lead to better health. In contrast, high-fat (HF) diet leads to disrupted circadian expression of metabolic factors and obesity. This paper focuses on circadian rhythms and their link to obesity.

  1. Circadian rhythms of women with fibromyalgia

    Science.gov (United States)

    Klerman, E. B.; Goldenberg, D. L.; Brown, E. N.; Maliszewski, A. M.; Adler, G. K.

    2001-01-01

    Fibromyalgia syndrome is a chronic and debilitating disorder characterized by widespread nonarticular musculoskeletal pain whose etiology is unknown. Many of the symptoms of this syndrome, including difficulty sleeping, fatigue, malaise, myalgias, gastrointestinal complaints, and decreased cognitive function, are similar to those observed in individuals whose circadian pacemaker is abnormally aligned with their sleep-wake schedule or with local environmental time. Abnormalities in melatonin and cortisol, two hormones whose secretion is strongly influenced by the circadian pacemaker, have been reported in women with fibromyalgia. We studied the circadian rhythms of 10 women with fibromyalgia and 12 control healthy women. The protocol controlled factors known to affect markers of the circadian system, including light levels, posture, sleep-wake state, meals, and activity. The timing of the events in the protocol were calculated relative to the habitual sleep-wake schedule of each individual subject. Under these conditions, we found no significant difference between the women with fibromyalgia and control women in the circadian amplitude or phase of rhythms of melatonin, cortisol, and core body temperature. The average circadian phases expressed in hours posthabitual bedtime for women with and without fibromyalgia were 3:43 +/- 0:19 and 3:46 +/- 0:13, respectively, for melatonin; 10:13 +/- 0:23 and 10:32 +/- 0:20, respectively for cortisol; and 5:19 +/- 0:19 and 4:57 +/- 0:33, respectively, for core body temperature phases. Both groups of women had similar circadian rhythms in self-reported alertness. Although pain and stiffness were significantly increased in women with fibromyalgia compared with healthy women, there were no circadian rhythms in either parameter. We suggest that abnormalities in circadian rhythmicity are not a primary cause of fibromyalgia or its symptoms.

  2. Circadian rhythms in handwriting kinematics and legibility.

    Science.gov (United States)

    Jasper, Isabelle; Gordijn, Marijke; Häussler, Andreas; Hermsdörfer, Joachim

    2011-08-01

    The aim of the present study was to analyze the circadian rhythmicity in handwriting kinematics and legibility and to compare the performance between Dutch and German writers. Two subject groups underwent a 40 h sleep deprivation protocol under Constant Routine conditions either in Groningen (10 Dutch subjects) or in Berlin (9 German subjects). Both groups wrote every 3h a test sentence of similar structure in their native language. Kinematic handwriting performance was assessed with a digitizing tablet and evaluated by writing speed, writing fluency, and script size. Writing speed (frequency of strokes and average velocity) revealed a clear circadian rhythm, with a parallel decline during night and a minimum around 3:00 h in the morning for both groups. Script size and movement fluency did not vary with time of day in neither group. Legibility of handwriting was evaluated by intra-individually ranking handwriting specimens of the 13 sessions by 10 German and 10 Dutch raters. Whereas legibility ratings of the German handwriting specimens deteriorated during night in parallel with slower writing speed, legibility of the Dutch handwriting deteriorated not until the next morning. In conclusion, the circadian rhythm of handwriting kinematics seems to be independent of script language at least among the two tested western countries. Moreover, handwriting legibility is also subject to a circadian rhythm which, however, seems to be influenced by variations in the assessment protocol. Copyright © 2010 Elsevier B.V. All rights reserved.

  3. Basic Principles of Interpersonal Social Rhythm Therapy in Bipolar Disorder

    Directory of Open Access Journals (Sweden)

    Gokben Hizli Sayar

    2014-08-01

    Full Text Available Interpersonal Social Rhythm Therapy is a psychotherapy modality that helps the patient recognize the relationship between disruptions in social rhythms and the onset of previous episodes of psychiatric disorders. It uses psychoeducation and behavioral techniques to maintain social rhythm and sleep/wake regularity. It is closely related to and ldquo;social zeitgeber theory and rdquo; that emphasizes the importance that social rhythm regularity may play in synchronization of circadian rhythms in individuals with or at risk for bipolar spectrum disorders. Interpersonal and social rhythm therapy have been shown to stabilize social rhythms and enhance course and outcome in bipolar disorder. This review focuses on the theoretical principles and the basic steps of interpersonal and social rhythm therapy as a psychotherapy approach in bipolar disorder. PubMed, Scopus, Google Scholar databases were searched without temporal restriction. Search terms included interpersonal social rhythm therapy, bipolar, mood disorders. Abstracts were reviewed for relevance, and randomized controlled trials of interpersonal and social rhythm therapy in bipolar disorder selected. These researches also summarized on the final part of this review. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2014; 6(4.000: 438-446

  4. Active and passive sexual roles that arise in Drosophila male-male courtship are modulated by dopamine levels in PPL2ab neurons

    OpenAIRE

    Shiu-Ling Chen; Yu-Hui Chen; Chuan-Chan Wang; Yhu-Wei Yu; Yu-Chen Tsai; Hsiao-Wen Hsu; Chia-Lin Wu; Pei-Yu Wang; Lien-Cheng Chen; Tsuo-Hung Lan; Tsai-Feng Fu

    2017-01-01

    The neurology of male sexuality has been poorly studied owing to difficulties in studying brain circuitry in humans. Dopamine (DA) is essential for both physiological and behavioural responses, including the regulation of sexuality. Previous studies have revealed that alterations in DA synthesis in dopaminergic neurons can induce male-male courtship behaviour, while increasing DA levels in the protocerebral posteriolateral dopaminergic cluster neuron 2ab (PPL2ab) may enhance the intensity of ...

  5. Biologic Rhythms Derived from Siberian Mammoths Hairs

    Energy Technology Data Exchange (ETDEWEB)

    M Spilde; A Lanzirotti; C Qualls; G Phillips; A Ali; L Agenbroad; O Appenzeller

    2011-12-31

    Hair is preserved for millennia in permafrost; it enshrines a record of biologic rhythms and offers a glimpse at chronobiology as it was in extinct animals. Here we compare biologic rhythms gleaned from mammoth's hairs with those of modern human hair. Four mammoths' hairs came from varying locations in Siberia 4600 km, four time zones, apart ranging in age between 18,000 and 20,000 years before present. We used two contemporaneous human hairs for comparison. Power spectra derived from hydrogen isotope ratios along the length of the hairs gave insight into biologic rhythms, which were different in the mammoths depending on location and differed from humans. Hair growth for mammoths was {approx}31 cms/year and {approx}16 cms/year for humans. Recurrent annual rhythms of slow and fast growth varying from 3.4 weeks/cycles to 8.7 weeks/cycles for slow periods and 1.2 weeks/cycles to 2.2 weeks/cycles for fast periods were identified in mammoth's hairs. The mineral content of mammoth's hairs was measured by electron microprobe analysis (k-ratios), which showed no differences in sulfur amongst the mammoth hairs but significantly more iron then in human hair. The fractal nature of the data derived from the hairs became evident in Mandelbrot sets derived from hydrogen isotope ratios, mineral content and geographic location. Confocal microscopy and scanning electron microscopy showed varied degrees of preservation of the cuticle largely independent of age but not location of the specimens. X-ray fluorescence microprobe and fluorescence computed micro-tomography analyses allowed evaluation of metal distribution and visualization of hollow tubes in the mammoth's hairs. Seasonal variations in iron and copper content combined with spectral analyses gave insights into variation in food intake of the animals. Biologic rhythms gleaned from power spectral plots obtained by modern methods revealed life style and behavior of extinct mega-fauna.

  6. The evolution of an academic-community partnership in the design, implementation, and evaluation of experience corps® Baltimore city: a courtship model.

    Science.gov (United States)

    Tan, Erwin J; McGill, Sylvia; Tanner, Elizabeth K; Carlson, Michelle C; Rebok, George W; Seeman, Teresa E; Fried, Linda P

    2014-04-01

    Experience Corps Baltimore City (EC) is a product of a partnership between the Greater Homewood Community Corporation (GHCC) and the Johns Hopkins Center on Aging and Health (COAH) that began in 1998. EC recruits volunteers aged 55 and older into high-impact mentoring and tutoring roles in public elementary schools that are designed to also benefit the volunteers. We describe the evolution of the GHCC-COAH partnership through the "Courtship Model." We describe how community-based participatory research principals, such as shared governance, were applied at the following stages: (1) partner selection, (2) getting serious, (3) commitment, and (4) leaving a legacy. EC could not have achieved its current level of success without academic-community partnership. In early stages of the "Courtship Model," GHCC and COAH were able to rely on the trust developed between the leadership of the partner organizations. Competing missions from different community and academic funders led to tension in later stages of the "Courtship Model" and necessitated a formal Memorandum of Understanding between the partners as they embarked on a randomized controlled trial. The GHCC-COAH partnership demonstrates how academic-community partnerships can serve as an engine for social innovation. The partnership could serve as a model for other communities seeking multiple funding sources to implement similar public health interventions that are based on national service models. Unified funding mechanisms would assist the formation of academic-community partnerships that could support the design, implementation, and the evaluation of community-based public health interventions.

  7. Sensorimotor rhythm neurofeedback as adjunct therapy for Parkinson's disease.

    Science.gov (United States)

    Philippens, Ingrid H C H M; Wubben, Jacqueline A; Vanwersch, Raymond A P; Estevao, Dave L; Tass, Peter A

    2017-08-01

    Neurofeedback may enhance compensatory brain mechanisms. EEG-based sensorimotor rhythm neurofeedback training was suggested to be beneficial in Parkinson's disease. In a placebo-controlled study in parkinsonian nonhuman primates we here show that sensorimotor rhythm neurofeedback training reduces MPTP-induced parkinsonian symptoms and both ON and OFF scores during classical L-DOPA treatment. Our findings encourage further development of sensorimotor rhythm neurofeedback training as adjunct therapy for Parkinson's disease which might help reduce L-DOPA-induced side effects.

  8. Fish and robot dancing together: bluefin killifish females respond differently to the courtship of a robot with varying color morphs.

    Science.gov (United States)

    Phamduy, P; Polverino, G; Fuller, R C; Porfiri, M

    2014-09-01

    The experimental integration of bioinspired robots in groups of social animals has become a valuable tool to understand the basis of social behavior and uncover the fundamental determinants of animal communication. In this study, we measured the preference of fertile female bluefin killifish (Lucania goodei) for robotic replicas whose aspect ratio, body size, motion pattern, and color morph were inspired by adult male killifish. The motion of the fish replica was controlled via a robotic platform, which simulated the typical courtship behavior observed in killifish males. The positional preferences of females were measured for three different color morphs (red, yellow, and blue). While variation in preference was high among females, females tend to spend more time in the vicinity of the yellow painted robot replicas. This preference may have emerged because the yellow robot replicas were very bright, particularly in the longer wavelengths (550–700 nm) compared to the red and blue replicas. These findings are in agreement with previous observations in mosquitofish and zebrafish on fish preference for artificially enhanced yellow pigmentation.

  9. Fish and robot dancing together: bluefin killifish females respond differently to the courtship of a robot with varying color morphs

    International Nuclear Information System (INIS)

    Phamduy, P; Polverino, G; Porfiri, M; Fuller, R C

    2014-01-01

    The experimental integration of bioinspired robots in groups of social animals has become a valuable tool to understand the basis of social behavior and uncover the fundamental determinants of animal communication. In this study, we measured the preference of fertile female bluefin killifish (Lucania goodei) for robotic replicas whose aspect ratio, body size, motion pattern, and color morph were inspired by adult male killifish. The motion of the fish replica was controlled via a robotic platform, which simulated the typical courtship behavior observed in killifish males. The positional preferences of females were measured for three different color morphs (red, yellow, and blue). While variation in preference was high among females, females tend to spend more time in the vicinity of the yellow painted robot replicas. This preference may have emerged because the yellow robot replicas were very bright, particularly in the longer wavelengths (550–700 nm) compared to the red and blue replicas. These findings are in agreement with previous observations in mosquitofish and zebrafish on fish preference for artificially enhanced yellow pigmentation. (paper)

  10. Cryptic confounding compounds: A brief consideration of the influences of anthropogenic contaminants on courtship and mating behavior

    Science.gov (United States)

    Blocker, Tomica D.; Ophir, Alexander G.

    2012-01-01

    Contaminants, like pesticides, polychlorinated biphenyls (PCBs), dioxins and metals, are persistent and ubiquitous and are known to threaten the environment. Traditionally, scientists have considered the direct physiological risks that these contaminants pose. However, scientists have just begun to integrate ethology and toxicology to investigate the effects that contaminants have on behavior. This review considers the potential for contaminant effects on mating behavior. Here we assess the growing body of research concerning disruptions in sexual differentiation, courtship, sexual receptivity, arousal, and mating. We discuss the implications of these disruptions on conservation efforts and highlight the importance of recognizing the potential for environmental stressors to affect behavioral experimentation. More specifically, we consider the negative implications for anthropogenic contaminants to affect the immediate behavior of animals, and their potential to have cascading and/or long-term effects on the behavioral ecology and evolution of populations. Overall, we aim to raise awareness of the confounding influence that contaminants can have, and promote caution when interpreting results where the potential for cryptic affects are possible. PMID:24244068

  11. Social Context Predicts Vocalization Use in the Courtship Behaviors of Weddell Seals (Leptonychotes weddellii: A Case Study

    Directory of Open Access Journals (Sweden)

    Ludivine R. Russell

    2016-05-01

    Full Text Available Despite previous research, no study has convincingly demonstrated what role if any vocalizations might play in the reproductive behavior of Weddell seals (Leptonychotes weddellii. To better understand that role, we created an artificial territory for an adult, male Weddell seal under the shore-fast ice in McMurdo Sound, Antarctica, and recorded its in situ vocalizations and non-vocal behaviors with an underwater video camera and hydrophone while alone, with another male, and with one or more females. Additionally, we simultaneously recorded the vocalizations and non-vocal behaviors from a female interacting with the male. Analysis of 86 hr of video and audio recordings showed: 1 the male vocalized more than the female, 2 the male’s vocal repertoire was larger than the females’ repertoire, 3 vocalizations changed quantitatively and qualitatively with social context, and 4 patterns of vocalizations and non-vocal behaviors were detected with Theme, pattern recognition software from Noldus Information Technology. These results provided strong evidence that vocalizations played an important role during courtship, and together with the significant behavioral sequences, vocal and non-vocal, they provided insight into the function of their vocalizations including chirps, growls, jaw claps, knocks, mews, trills, and trills + knocks.

  12. Standing down Straight: Jump Rhythm Technique's Rhythm-Driven, Community-Directed Approach to Dance Education

    Science.gov (United States)

    Siegenfeld, Billy

    2009-01-01

    "Standing down straight" means to stand on two feet with both stability and relaxation. Using standing down straight as the foundation of class work, Jump Rhythm Technique offers a fresh alternative to conventional systems of dance study. It bases its pedagogy on three behaviors: grounding the body so that it can move with power and efficiency,…

  13. Chaos control applied to heart rhythm dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Borem Ferreira, Bianca, E-mail: biaborem@gmail.com [Universidade Federal do Rio de Janeiro, COPPE, Department of Mechanical Engineering, P.O. Box 68.503, 21.941.972 Rio de Janeiro, RJ (Brazil); Souza de Paula, Aline, E-mail: alinedepaula@unb.br [Universidade de Brasi' lia, Department of Mechanical Engineering, 70.910.900 Brasilia, DF (Brazil); Amorim Savi, Marcelo, E-mail: savi@mecanica.ufrj.br [Universidade Federal do Rio de Janeiro, COPPE, Department of Mechanical Engineering, P.O. Box 68.503, 21.941.972 Rio de Janeiro, RJ (Brazil)

    2011-08-15

    Highlights: > A natural cardiac pacemaker is modeled by a modified Van der Pol oscillator. > Responses related to normal and chaotic, pathological functioning of the heart are investigated. > Chaos control methods are applied to avoid pathological behaviors of heart dynamics. > Different approaches are treated: stabilization of unstable periodic orbits and chaos suppression. - Abstract: The dynamics of cardiovascular rhythms have been widely studied due to the key aspects of the heart in the physiology of living beings. Cardiac rhythms can be either periodic or chaotic, being respectively related to normal and pathological physiological functioning. In this regard, chaos control methods may be useful to promote the stabilization of unstable periodic orbits using small perturbations. In this article, the extended time-delayed feedback control method is applied to a natural cardiac pacemaker described by a mathematical model. The model consists of a modified Van der Pol equation that reproduces the behavior of this pacemaker. Results show the ability of the chaos control strategy to control the system response performing either the stabilization of unstable periodic orbits or the suppression of chaotic response, avoiding behaviors associated with critical cardiac pathologies.

  14. Circadian rhythm and its role in malignancy

    Directory of Open Access Journals (Sweden)

    Mahmood Saqib

    2010-03-01

    Full Text Available Abstract Circadian rhythms are daily oscillations of multiple biological processes directed by endogenous clocks. The circadian timing system comprises peripheral oscillators located in most tissues of the body and a central pacemaker located in the suprachiasmatic nucleus (SCN of the hypothalamus. Circadian genes and the proteins produced by these genes constitute the molecular components of the circadian oscillator which form positive/negative feedback loops and generate circadian rhythms. The circadian regulation extends beyond clock genes to involve various clock-controlled genes (CCGs including various cell cycle genes. Aberrant expression of circadian clock genes could have important consequences on the transactivation of downstream targets that control the cell cycle and on the ability of cells to undergo apoptosis. This may lead to genomic instability and accelerated cellular proliferation potentially promoting carcinogenesis. Different lines of evidence in mice and humans suggest that cancer may be a circadian-related disorder. The genetic or functional disruption of the molecular circadian clock has been found in various cancers including breast, ovarian, endometrial, prostate and hematological cancers. The acquisition of current data in circadian clock mechanism may help chronotherapy, which takes into consideration the biological time to improve treatments by devising new therapeutic approaches for treating circadian-related disorders, especially cancer.

  15. Turn exchange rhythm in English dialogues

    Science.gov (United States)

    Fon, Janice

    2005-09-01

    This study looked at the relationship between rhythm and exchange type in British English, a stress-timed language, and Singaporean English, a syllable-timed language, using a spontaneous speech corpus. Exchange intervals (EIs), or the time difference between the end of one speaker and the beginning of another, were measured and exchanges of different types were labeled. Results showed that, in a dialogue, EIs were generally limited to a narrow range. However, within this range, EIs had at least four functions. First, EIs were reflective of the cognitive load and functioned as a way to differentiate various exchange types. Those requiring more cognitive resources, such as question-and-answer pairs, generally needed longer EIs than those not as cognitively loaded, such as backchanneling pairs. Second, EIs were indicative of linguistic rhythm. Singaporean English tended to have shorter EIs than British English. Third, EIs were reflective of politeness. The degree of politeness correlated negatively with EI. Shorter EIs showed a higher degree of respect. Finally, EIs were also indicative of the level of insecurity of a speaker, which was best reflected by gender differences. Females in general had longer EIs than males.

  16. Temperature compensation and entrainment in circadian rhythms

    International Nuclear Information System (INIS)

    Bodenstein, C; Heiland, I; Schuster, S

    2012-01-01

    To anticipate daily variations in the environment and coordinate biological activities into a daily cycle many organisms possess a circadian clock. In the absence of external time cues the circadian rhythm persists with a period of approximately 24 h. The clock phase can be shifted by single pulses of light, darkness, chemicals, or temperature and this allows entrainment of the clock to exactly 24 h by cycles of these zeitgebers. On the other hand, the period of the circadian rhythm is kept relatively constant within a physiological range of constant temperatures, which means that the oscillator is temperature compensated. The mechanisms behind temperature compensation and temperature entrainment are not fully understood, neither biochemically nor mathematically. Here, we theoretically investigate the interplay of temperature compensation and entrainment in general oscillatory systems. We first give an analytical treatment for small temperature shifts and derive that every temperature-compensated oscillator is entrainable to external small-amplitude temperature cycles. Temperature compensation ensures that this entrainment region is always centered at the endogenous period regardless of possible seasonal temperature differences. Moreover, for small temperature cycles the entrainment region of the oscillator is potentially larger for rectangular pulses. For large temperature shifts we numerically analyze different circadian clock models proposed in the literature with respect to these properties. We observe that for such large temperature shifts sinusoidal or gradual temperature cycles allow a larger entrainment region than rectangular cycles. (paper)

  17. Strength of Gamma Rhythm Depends on Normalization

    Science.gov (United States)

    Ray, Supratim; Ni, Amy M.; Maunsell, John H. R.

    2013-01-01

    Neuronal assemblies often exhibit stimulus-induced rhythmic activity in the gamma range (30–80 Hz), whose magnitude depends on the attentional load. This has led to the suggestion that gamma rhythms form dynamic communication channels across cortical areas processing the features of behaviorally relevant stimuli. Recently, attention has been linked to a normalization mechanism, in which the response of a neuron is suppressed (normalized) by the overall activity of a large pool of neighboring neurons. In this model, attention increases the excitatory drive received by the neuron, which in turn also increases the strength of normalization, thereby changing the balance of excitation and inhibition. Recent studies have shown that gamma power also depends on such excitatory–inhibitory interactions. Could modulation in gamma power during an attention task be a reflection of the changes in the underlying excitation–inhibition interactions? By manipulating the normalization strength independent of attentional load in macaque monkeys, we show that gamma power increases with increasing normalization, even when the attentional load is fixed. Further, manipulations of attention that increase normalization increase gamma power, even when they decrease the firing rate. Thus, gamma rhythms could be a reflection of changes in the relative strengths of excitation and normalization rather than playing a functional role in communication or control. PMID:23393427

  18. Circadian Rhythms, Sleep Deprivation, and Human Performance

    Science.gov (United States)

    Goel, Namni; Basner, Mathias; Rao, Hengyi; Dinges, David F.

    2014-01-01

    Much of the current science on, and mathematical modeling of, dynamic changes in human performance within and between days is dominated by the two-process model of sleep–wake regulation, which posits a neurobiological drive for sleep that varies homeostatically (increasing as a saturating exponential during wakefulness and decreasing in a like manner during sleep), and a circadian process that neurobiologically modulates both the homeostatic drive for sleep and waking alertness and performance. Endogenous circadian rhythms in neurobehavioral functions, including physiological alertness and cognitive performance, have been demonstrated using special laboratory protocols that reveal the interaction of the biological clock with the sleep homeostatic drive. Individual differences in circadian rhythms and genetic and other components underlying such differences also influence waking neurobehavioral functions. Both acute total sleep deprivation and chronic sleep restriction increase homeostatic sleep drive and degrade waking neurobehavioral functions as reflected in sleepiness, attention, cognitive speed, and memory. Recent evidence indicating a high degree of stability in neurobehavioral responses to sleep loss suggests that these trait-like individual differences are phenotypic and likely involve genetic components, including circadian genes. Recent experiments have revealed both sleep homeostatic and circadian effects on brain metabolism and neural activation. Investigation of the neural and genetic mechanisms underlying the dynamically complex interaction between sleep homeostasis and circadian systems is beginning. A key goal of this work is to identify biomarkers that accurately predict human performance in situations in which the circadian and sleep homeostatic systems are perturbed. PMID:23899598

  19. Rhythms of EEG and cognitive processes

    Directory of Open Access Journals (Sweden)

    Novikova S.I.

    2015-06-01

    Full Text Available The study of cognitive processes is regarded to be more effective if it combines a psychological approach with a neurophysiological one. This approach makes it possible to come closer to understanding of the basic mechanisms of different cognitive processes, to describe the patterns of forming these mechanisms in ontogenesis, to investigate the origin of cognitive impairments, and to develop intervention techniques. The promising way of investigating the mechanisms of cognitive functions is the electroencephalography (EEG. This is a non-invasive, safe, and relatively cheap method of research of the functional condition of the brain. The characteristics of EEG rhythms, recorded with different cognitive loads, reflect the processes of functional modulation of neural network activity of the cortex, which serves the neurophysiologic basis for attention, memory and other cognitive processes. The article provides an overview of works containing the analysis of the alpha and theta rhythms’ dynamics in various states of wakefulness. It also introduces the substantiation of methodology of functional regulatory approach to the interpretation of behaviors of EEG rhythms.

  20. A circadian rhythm regulating hyphal melanization in Cercospora kikuchii.

    Science.gov (United States)

    Bluhm, Burton H; Burnham, A Michele; Dunkle, Larry D

    2010-01-01

    Many metabolic and developmental processes in fungi are controlled by biological rhythms. Circadian rhythms approximate a daily (24 h) cycle and have been thoroughly studied in the model fungus, Neurospora crassa. However relatively few examples of true circadian rhythms have been documented among other filamentous fungi. In this study we describe a circadian rhythm underlying hyphal melanization in Cercospora kikuchii, an important pathogen of soybean. After growth in light or light : dark cycles, colonies transferred to darkness produced zonate bands of melanized hyphae interspersed with bands of hyaline hyphae. Rhythmic production of bands was remarkably persistent in the absence of external cues, lasting at least 7 d after transfer to darkness, and was compensated over a range of temperatures. As in N. crassa, blue light but not red light was sufficient to entrain the circadian rhythm in C. kikuchii, and a putative ortholog of white collar-1, one of the genes required for light responses in N. crassa, was identified in C. kikuchii. Circadian regulation of melanization is conserved in other members of the genus: Similar rhythms were identified in another field isolate of C. kikuchii as well as field isolates of C. beticola and C. sorghi, but not in wild-type strains of C. zeae-maydis or C. zeina. This report represents the first documented circadian rhythm among Dothideomycete fungi and provides a new opportunity to dissect the molecular basis of circadian rhythms among filamentous fungi.

  1. Effects of Some Aspects of Rhythm on Tempo Perception.

    Science.gov (United States)

    Wang, Cecilia Chu

    1984-01-01

    Results indicated that significantly more time is needed to perceive tempo increase than tempo decrease, uneven rhythm then even rhythm, and melody alone than melody with accompaniment. Furthermore, significant interaction effects involving beat locations of tempo change suggest that differential groupings may be a factor in tempo discrimination.…

  2. Effects of tempo and timing of simple musical rhythms

    NARCIS (Netherlands)

    Repp, B.H.; Windsor, W.L.; Desain, P.W.M.

    2002-01-01

    In this study we investigated whether and how the timing of musical rhythms changes with tempo. Twelve skilled pianists played a monophonic 8-bar melody in 21 different rhythmic versions at 4 different tempi. Within bars, the rhythms represented all possible ordered pairs and triplets of note values

  3. A Circadian Rhythm Regulating Hyphal Melanization in Cercospora Kikuchii

    Science.gov (United States)

    Circadian rhythms, biochemical or developmental processes with a period length of approximately 24 hours, are thoroughly documented in plants and animals. However, virtually all of what is currently known about circadian rhythms in fungi is derived from the model fungus, Neurospora crassa, including...

  4. A novel animal model linking adiposity to altered circadian rhythms

    Science.gov (United States)

    Researchers have provided evidence for a link between obesity and altered circadian rhythms (e.g., shift work, disrupted sleep), but the mechanism for this association is still unknown. Adipocytes possess an intrinsic circadian clock, and circadian rhythms in adipocytokines and adipose tissue metab...

  5. Circadian Activity Rhythms, Time Urgency, and Achievement Concerns.

    Science.gov (United States)

    Watts, Barbara L.

    Many physiological and psychological processes fluctuate throughout the day in fairly stable, rhythmic patterns. The relationship between individual differences in circadian activity rhythms and a sense of time urgency were explored as well as a number of achievement-related variables. Undergraduates (N=308), whose circadian activity rhythms were…

  6. Interactive Rhythm Learning System by Combining Tablet Computers and Robots

    Directory of Open Access Journals (Sweden)

    Chien-Hsing Chou

    2017-03-01

    Full Text Available This study proposes a percussion learning device that combines tablet computers and robots. This device comprises two systems: a rhythm teaching system, in which users can compose and practice rhythms by using a tablet computer, and a robot performance system. First, teachers compose the rhythm training contents on the tablet computer. Then, the learners practice these percussion exercises by using the tablet computer and a small drum set. The teaching system provides a new and user-friendly score editing interface for composing a rhythm exercise. It also provides a rhythm rating function to facilitate percussion training for children and improve the stability of rhythmic beating. To encourage children to practice percussion exercises, a robotic performance system is used to interact with the children; this system can perform percussion exercises for students to listen to and then help them practice the exercise. This interaction enhances children’s interest and motivation to learn and practice rhythm exercises. The results of experimental course and field trials reveal that the proposed system not only increases students’ interest and efficiency in learning but also helps them in understanding musical rhythms through interaction and composing simple rhythms.

  7. Unexpected diversity in socially synchronized rhythms of shorebirds

    NARCIS (Netherlands)

    Bulla, Martin; Valcu, Mihai; Dokter, Adriaan M; Dondua, Alexei G; Kosztolányi, András; Helm, Barbara; Sandercock, Brett K; Casler, Bruce; Ens, Bruno J.; Spiegel, Caleb S; Hassell, Chris J; Küpper, Clemens; Minton, Clive; Burgas, Daniel; Lank, David B; Payer, David C; Loktionov, Egor Y; Nol, Erica; Kwon, Eunbi; Smith, Fletcher; Gates, H River; Vitnerová, Hana; Prüter, Hanna; Johnson, James A; St Clair, James J H; Lamarre, Jean-François; Rausch, Jennie; Reneerkens, Jeroen; Conklin, Jesse R; Burger, Joanna; Liebezeit, Joe; Bêty, Joël; Coleman, Jonathan T; Figuerola, Jordi; Hooijmeijer, Joslyn; Alves, José A; Smith, Joseph A M; Weidinger, Karel; Koivula, Kari; Gosbell, Ken; Exo, Klaus-Michael; Niles, Larry; Koloski, Laura; McKinnon, Laura; Praus, Libor; Klaassen, Marcel; Giroux, Marie-Andrée; Sládeček, Martin; Boldenow, Megan L; Goldstein, Michael I; Šálek, Miroslav; Senner, Nathan; Rönkä, Nelli; Lecomte, Nicolas; Gilg, Olivier; Vincze, Orsolya; Johnson, Oscar W; Smith, Paul A; Woodard, Paul F; Tomkovich, Pavel S; Battley, Phil F; Bentzen, Rebecca; Lanctot, Richard B; Porter, Ron; Saalfeld, Sarah T; Freeman, Scott; Brown, Stephen C; Yezerinac, Stephen; Székely, Tamás; Montalvo, Tomás; Piersma, Theunis; Loverti, Vanessa; Pakanen, Veli-Matti; Tijsen, Wim; Kempenaers, Bart

    2016-01-01

    The behavioural rhythms of organisms are thought to be under strong selection, influenced by the rhythmicity of the environment. Such behavioural rhythms are well studied in isolated individuals under laboratory conditions, but free-living individuals have to temporally synchronize their activities

  8. The evolution of rhythm cognition: Timing in music and speech

    NARCIS (Netherlands)

    Ravignani, A.; Honing, H.; Kotz, S.A.

    This editorial serves a number of purposes. First, it aims at summarizing and discussing 33 accepted contributions to the special issue ‘The evolution of rhythm cognition: Timing in music and speech’. The major focus of the issue is the cognitive neuroscience of rhythm, intended as a neurobehavioral

  9. Interaction with Mass Media: The Importance of Rhythm and Tempo.

    Science.gov (United States)

    Snow, Robert P.

    1987-01-01

    Stresses that understanding the impact of interaction with mass media requires conceptualizing media as an institutionalized social form. A critical feature of this process is the grammatical character of media interaction in the form of rhythm and tempo, because these rhythms and tempos become established in everyday routine. (SKC)

  10. ‘Ragged Time’ in Intra-panel Comics Rhythms

    Directory of Open Access Journals (Sweden)

    Corry Shores

    2016-07-01

    Full Text Available A phenomenological method of comics analysis can be useful when we need to uncover the structural features of the comics experience itself. One fruitful application would be in the study of irregular intra-panel rhythms, where the temporalized divisions are not visibly indicated but rather are only experienced. By means of Gilles Deleuze’s notion of rhythmic repetition and his elaboration of it through Olivier Messiaen’s theory of ‘kinetic’ rhythm, we will formulate a conception of visual rhythm as being based on metrical irregularity. We further explicate this concept of irregular rhythm by drawing upon the notion of ‘ragged time’ in the early jazz musical form, ragtime. We finally test its usefulness by examining how the ‘jazzy’ rhythms of Cubist-styled panels by Art Spiegelman and Mary Fleener generate an experience of ragged time.

  11. FEMALE CONTROL OF SPERM TRANSFER AND INTRASPECIFIC VARIATION IN SPERM PRECEDENCE: ANTECEDENTS TO THE EVOLUTION OF A COURTSHIP FOOD GIFT.

    Science.gov (United States)

    Sakaluk, Scott K; Eggert, Anne-Katrin

    1996-04-01

    Manipulation of ejaculates is believed to be an important avenue of female choice throughout the animal kingdom, but evidence of its importance to sexual selection remains scarce. In crickets, such manipulation is manifest in the premature removal of the externally attached spermatophore, which may afford females an important means of postcopulatory mate choice. We tested the hypothesis that premature spermatophore removal contributes significantly to intraspecific variation in sperm precedence by (1) experimentally manipulating spermatophore attachment durations of competing male Gryllodes sigillatus and (2) employing protein electrophoresis to determine the paternity of doubly mated females. The relative spermatophore attachment durations of competing males had a significant influence on male paternity, but the pattern of sperm precedence deviated significantly from the predictions of an ideal lottery. Instead, paternity data and morphological evidence accorded best with a model of partial sperm displacement derived here. Our model is similar to a displacement model of Parker et al. in that sperm of the second male mixes instantaneously with that of the first throughout the displacement process, but the novel feature of our model is that the number of sperm displaced is only a fraction of the number of sperm transferred by the second male. Regardless of the underlying mechanism, female G. sigillatus can clearly alter the paternity of their offspring through their spermatophore-removal behavior, and employ such cryptic choice in favoring larger males and those providing larger courtship food gifts. We discuss how female control of sperm transfer and intraspecific variation in sperm precedence may be important precursors to the evolution of gift giving in insects. © 1996 The Society for the Study of Evolution.

  12. Cross-cultural influences on rhythm processing: reproduction, discrimination, and beat tapping.

    Science.gov (United States)

    Cameron, Daniel J; Bentley, Jocelyn; Grahn, Jessica A

    2015-01-01

    The structures of musical rhythm differ between cultures, despite the fact that the ability to entrain movement to musical rhythm occurs in virtually all individuals across cultures. To measure the influence of culture on rhythm processing, we tested East African and North American adults on perception, production, and beat tapping for rhythms derived from East African and Western music. To assess rhythm perception, participants identified whether pairs of rhythms were the same or different. To assess rhythm production, participants reproduced rhythms after hearing them. To assess beat tapping, participants tapped the beat along with repeated rhythms. We expected that performance in all three tasks would be influenced by the culture of the participant and the culture of the rhythm. Specifically, we predicted that a participant's ability to discriminate, reproduce, and accurately tap the beat would be better for rhythms from their own culture than for rhythms from another culture. In the rhythm discrimination task, there were no differences in discriminating culturally familiar and unfamiliar rhythms. In the rhythm reproduction task, both groups reproduced East African rhythms more accurately than Western rhythms, but East African participants also showed an effect of cultural familiarity, leading to a significant interaction. In the beat tapping task, participants in both groups tapped the beat more accurately for culturally familiar than for unfamiliar rhythms. Moreover, there were differences between the two participant groups, and between the two types of rhythms, in the metrical level selected for beat tapping. The results demonstrate that culture does influence the processing of musical rhythm. In terms of the function of musical rhythm, our results are consistent with theories that musical rhythm enables synchronization. Musical rhythm may foster musical cultural identity by enabling within-group synchronization to music, perhaps supporting social cohesion.

  13. Circadian Rhythms, Sleep, and Disorders of Aging.

    Science.gov (United States)

    Mattis, Joanna; Sehgal, Amita

    2016-04-01

    Sleep-wake cycles are known to be disrupted in people with neurodegenerative disorders. These findings are now supported by data from animal models for some of these disorders, raising the question of whether the disrupted sleep/circadian regulation contributes to the loss of neural function. As circadian rhythms and sleep consolidation also break down with normal aging, changes in these may be part of what makes aging a risk factor for disorders like Alzheimer's disease (AD). Mechanisms underlying the connection between circadian/sleep dysregulation and neurodegeneration remain unclear, but several recent studies provide interesting possibilities. While mechanistic analysis is under way, it is worth considering treatment of circadian/sleep disruption as a means to alleviate symptoms of neurodegenerative disorders. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Choreographing Compassion: A Clinical Adventure of Rhythms.

    Science.gov (United States)

    Yopst, Charles George

    2015-06-01

    Compassion is a primary catalyst motivating positive human relationships, especially of those less fortunate. Our rhythms Expand-Contract of our own non-verbal body joints movements and of the law of counter-balance, enable us to identify which of nine innate affects-emotions is directing the body's movements. With this reading, a trained person can synchronize choreography of these into fully authentic compassion between two or more persons. Primary references for this are the late Silvan S. Tomkins's four volumes "Affect Imagery Consciousness," and choreographers the late Rudolf Laban, Warren Lamb, Irmgard Bartenieff, and Marian Chace. Professionals, clinicians, and laity counselors can all use these. © The Author(s) 2015.

  15. Effect of Pilates Training on Alpha Rhythm

    Directory of Open Access Journals (Sweden)

    Zhijie Bian

    2013-01-01

    Full Text Available In this study, the effect of Pilates training on the brain function was investigated through five case studies. Alpha rhythm changes during the Pilates training over the different regions and the whole brain were mainly analyzed, including power spectral density and global synchronization index (GSI. It was found that the neural network of the brain was more active, and the synchronization strength reduced in the frontal and temporal regions due to the Pilates training. These results supported that the Pilates training is very beneficial for improving brain function or intelligence. These findings maybe give us some line evidence to suggest that the Pilates training is very helpful for the intervention of brain degenerative diseases and cogitative dysfunction rehabilitation.

  16. Effect of Pilates Training on Alpha Rhythm

    Science.gov (United States)

    Bian, Zhijie; Sun, Hongmin; Lu, Chengbiao; Yao, Li; Chen, Shengyong; Li, Xiaoli

    2013-01-01

    In this study, the effect of Pilates training on the brain function was investigated through five case studies. Alpha rhythm changes during the Pilates training over the different regions and the whole brain were mainly analyzed, including power spectral density and global synchronization index (GSI). It was found that the neural network of the brain was more active, and the synchronization strength reduced in the frontal and temporal regions due to the Pilates training. These results supported that the Pilates training is very beneficial for improving brain function or intelligence. These findings maybe give us some line evidence to suggest that the Pilates training is very helpful for the intervention of brain degenerative diseases and cogitative dysfunction rehabilitation. PMID:23861723

  17. Sensorimotor Rhythm Neurofeedback Enhances Golf Putting Performance.

    Science.gov (United States)

    Cheng, Ming-Yang; Huang, Chung-Ju; Chang, Yu-Kai; Koester, Dirk; Schack, Thomas; Hung, Tsung-Min

    2015-12-01

    Sensorimotor rhythm (SMR) activity has been related to automaticity during skilled action execution. However, few studies have bridged the causal link between SMR activity and sports performance. This study investigated the effect of SMR neurofeedback training (SMR NFT) on golf putting performance. We hypothesized that preelite golfers would exhibit enhanced putting performance after SMR NFT. Sixteen preelite golfers were recruited and randomly assigned into either an SMR or a control group. Participants were asked to perform putting while electroencephalogram (EEG) was recorded, both before and after intervention. Our results showed that the SMR group performed more accurately when putting and exhibited greater SMR power than the control group after 8 intervention sessions. This study concludes that SMR NFT is effective for increasing SMR during action preparation and for enhancing golf putting performance. Moreover, greater SMR activity might be an EEG signature of improved attention processing, which induces superior putting performance.

  18. Clinical learning environments: place, artefacts and rhythm.

    Science.gov (United States)

    Sheehan, Dale; Jowsey, Tanisha; Parwaiz, Mariam; Birch, Mark; Seaton, Philippa; Shaw, Susan; Duggan, Alison; Wilkinson, Tim

    2017-10-01

    Health care practitioners learn through experience in clinical environments in which supervision is a key component, but how that learning occurs outside the supervision relationship remains largely unknown. This study explores the environmental factors that inform and support workplace learning within a clinical environment. An observational study drawing on ethnographic methods was undertaken in a general medicine ward. Observers paid attention to interactions among staff members that involved potential teaching and learning moments that occurred and were visible in the course of routine work. General purpose thematic analysis of field notes was undertaken. A total of 376 observations were undertaken and documented. The findings suggest that place (location of interaction), rhythm (regularity of activities occurring in the ward) and artefacts (objects and equipment) were strong influences on the interactions and exchanges that occurred. Each of these themes had inherent tensions that could promote or inhibit engagement and therefore learning opportunities. Although many learning opportunities were available, not all were taken up or recognised by the participants. We describe and make explicit how the natural environment of a medical ward and flow of work through patient care contribute to the learning architecture, and how this creates or inhibits opportunities for learning. Awareness of learning opportunities was often tacit and not explicit for either supervisor or learner. We identify strategies through which tensions inherent within space, artefacts and the rhythms of work can be resolved and learning opportunities maximised. © 2017 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

  19. Circadian Rhythms in Diet-Induced Obesity.

    Science.gov (United States)

    Engin, Atilla

    2017-01-01

    The biological clocks of the circadian timing system coordinate cellular and physiological processes and synchronizes these with daily cycles, feeding patterns also regulates circadian clocks. The clock genes and adipocytokines show circadian rhythmicity. Dysfunction of these genes are involved in the alteration of these adipokines during the development of obesity. Food availability promotes the stimuli associated with food intake which is a circadian oscillator outside of the suprachiasmatic nucleus (SCN). Its circadian rhythm is arranged with the predictable daily mealtimes. Food anticipatory activity is mediated by a self-sustained circadian timing and its principal component is food entrained oscillator. However, the hypothalamus has a crucial role in the regulation of energy balance rather than food intake. Fatty acids or their metabolites can modulate neuronal activity by brain nutrient-sensing neurons involved in the regulation of energy and glucose homeostasis. The timing of three-meal schedules indicates close association with the plasma levels of insulin and preceding food availability. Desynchronization between the central and peripheral clocks by altered timing of food intake and diet composition can lead to uncoupling of peripheral clocks from the central pacemaker and to the development of metabolic disorders. Metabolic dysfunction is associated with circadian disturbances at both central and peripheral levels and, eventual disruption of circadian clock functioning can lead to obesity. While CLOCK expression levels are increased with high fat diet-induced obesity, peroxisome proliferator-activated receptor (PPAR) alpha increases the transcriptional level of brain and muscle ARNT-like 1 (BMAL1) in obese subjects. Consequently, disruption of clock genes results in dyslipidemia, insulin resistance and obesity. Modifying the time of feeding alone can greatly affect body weight. Changes in the circadian clock are associated with temporal alterations in

  20. Biological and psychological rhythms: an integrative approach to rhythm disturbances in autistic disorder.

    Science.gov (United States)

    Botbol, Michel; Cabon, Philippe; Kermarrec, Solenn; Tordjman, Sylvie

    2013-09-01

    Biological rhythms are crucial phenomena that are perfect examples of the adaptation of organisms to their environment. A considerable amount of work has described different types of biological rhythms (from circadian to ultradian), individual differences in their patterns and the complexity of their regulation. In particular, the regulation and maturation of the sleep-wake cycle have been thoroughly studied. Its desynchronization, both endogenous and exogenous, is now well understood, as are its consequences for cognitive impairments and health problems. From a completely different perspective, psychoanalysts have shown a growing interest in the rhythms of psychic life. This interest extends beyond the original focus of psychoanalysis on dreams and the sleep-wake cycle, incorporating central theoretical and practical psychoanalytic issues related to the core functioning of the psychic life: the rhythmic structures of drive dynamics, intersubjective developmental processes and psychic containment functions. Psychopathological and biological approaches to the study of infantile autism reveal the importance of specific biological and psychological rhythmic disturbances in this disorder. Considering data and hypotheses from both perspectives, this paper proposes an integrative approach to the study of these rhythmic disturbances and offers an etiopathogenic hypothesis based on this integrative approach. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. A Reliable Method for Rhythm Analysis during Cardiopulmonary Resuscitation

    Directory of Open Access Journals (Sweden)

    U. Ayala

    2014-01-01

    Full Text Available Interruptions in cardiopulmonary resuscitation (CPR compromise defibrillation success. However, CPR must be interrupted to analyze the rhythm because although current methods for rhythm analysis during CPR have high sensitivity for shockable rhythms, the specificity for nonshockable rhythms is still too low. This paper introduces a new approach to rhythm analysis during CPR that combines two strategies: a state-of-the-art CPR artifact suppression filter and a shock advice algorithm (SAA designed to optimally classify the filtered signal. Emphasis is on designing an algorithm with high specificity. The SAA includes a detector for low electrical activity rhythms to increase the specificity, and a shock/no-shock decision algorithm based on a support vector machine classifier using slope and frequency features. For this study, 1185 shockable and 6482 nonshockable 9-s segments corrupted by CPR artifacts were obtained from 247 patients suffering out-of-hospital cardiac arrest. The segments were split into a training and a test set. For the test set, the sensitivity and specificity for rhythm analysis during CPR were 91.0% and 96.6%, respectively. This new approach shows an important increase in specificity without compromising the sensitivity when compared to previous studies.

  2. Chronotype and circadian rhythm in bipolar disorder: A systematic review.

    Science.gov (United States)

    Melo, Matias C A; Abreu, Rafael L C; Linhares Neto, Vicente B; de Bruin, Pedro F C; de Bruin, Veralice M S

    2017-08-01

    Despite a complex relationship between mood, sleep and rhythm, the impact of circadian disruptions on bipolar disorder (BD) has not been clarified. The purpose of this systematic review was to define current evidence regarding chronotype and circadian rhythm patterns in BD patients. 42 studies were included, involving 3432 BD patients. Disruption of the biological rhythm was identified, even in drug-naïve BD patients and independently of mood status. Daily profiles of melatonin levels and cortisol indicated a delayed phase. Depression was more frequently associated with circadian alterations than euthymia. Few studies evaluated mania, demonstrating irregular rhythms. Evening type was more common in BD adults. Studies about the influence of chronotype on depressive symptoms showed conflicting results. Only one investigation observed the influences of chronotype in mania, revealing no significant association. Effects of psychoeducation and lithium on rhythm in BD patients were poorly studied, demonstrating no improvement of rhythm parameters. Studies about genetics are incipient. In conclusion, disruption in circadian rhythm and eveningness are common in BD. Prospective research evaluating the impact of circadian disruption on mood symptoms, metabolism, seasonality, the influence of age and the effects of mood stabilizers are needed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Neural responses to complex auditory rhythms: the role of attending

    Directory of Open Access Journals (Sweden)

    Heather L Chapin

    2010-12-01

    Full Text Available The aim of this study was to explore the role of attention in pulse and meter perception using complex rhythms. We used a selective attention paradigm in which participants attended to either a complex auditory rhythm or a visually presented word list. Performance on a reproduction task was used to gauge whether participants were attending to the appropriate stimulus. We hypothesized that attention to complex rhythms – which contain no energy at the pulse frequency – would lead to activations in motor areas involved in pulse perception. Moreover, because multiple repetitions of a complex rhythm are needed to perceive a pulse, activations in pulse related areas would be seen only after sufficient time had elapsed for pulse perception to develop. Selective attention was also expected to modulate activity in sensory areas specific to the modality. We found that selective attention to rhythms led to increased BOLD responses in basal ganglia, and basal ganglia activity was observed only after the rhythms had cycled enough times for a stable pulse percept to develop. These observations suggest that attention is needed to recruit motor activations associated with the perception of pulse in complex rhythms. Moreover, attention to the auditory stimulus enhanced activity in an attentional sensory network including primary auditory, insula, anterior cingulate, and prefrontal cortex, and suppressed activity in sensory areas associated with attending to the visual stimulus.

  4. Cross-Cultural Influences on Rhythm Processing: Reproduction, Discrimination, and Beat Tapping

    Directory of Open Access Journals (Sweden)

    Daniel J Cameron

    2015-04-01

    Full Text Available The structures of musical rhythm differ between cultures, despite the fact that the ability to synchronize one’s movements to musical rhythms appears to be universal. To measure the influence of culture on rhythm processing, we tested East African and North American adults on the perception, production, and beat tapping of rhythms derived from East African and Western music. To assess rhythm perception, participants identified whether pairs of rhythms were same or different. To assess rhythm production, participants reproduced rhythms after hearing them. To assess beat tapping, participants tapped the beat along with repeated rhythms. We expected that performance in all three tasks would be influenced both by the culture of the participant and by the culture of the rhythm. Specifically, we predicted that a participant’s ability to discriminate, reproduce, and accurately tap the beat would be better for rhythms from their own culture than for rhythms from another culture. In the rhythm discrimination task, there were no differences in discriminating culturally familiar and unfamiliar rhythms. In the rhythm reproduction task, both groups reproduced East African rhythms more accurately than Western rhythms, but East African participants also showed an effect of cultural familiarity, leading to a significant interaction. In the beat tapping task, participants in both groups tapped the beat more accurately for culturally familiar than unfamiliar rhythms. The results demonstrate that culture does influence the processing of musical rhythm. In terms of the function of musical rhythm, our results are consistent with theories that musical rhythm enables synchronization. Musical rhythm may foster musical cultural identity by enabling within-group synchronization to music, perhaps supporting social cohesion.

  5. The role of the daily feeding rhythm in the regulation of the day/night rhythm in triglyceride secretion in rats.

    Science.gov (United States)

    Su, Yan; Foppen, Ewout; Mansur Machado, Frederico Sander; Fliers, Eric; Kalsbeek, Andries

    2018-02-15

    Plasma triglyceride (TG) levels show a clear daily rhythm, however, thus far it is still unknown whether this rhythm results from a daily rhythm in TG production, TG uptake or both. Previous studies have shown that feeding activity affects plasma TG concentrations, but it is not clear how the daily rhythm in feeding activity affects plasma TG concentrations. In the present study, we measured plasma TG concentrations and TG secretion rates in rats at 6 Zeitgeber times to investigate whether plasma TG concentrations and TG secretion show a daily rhythm. We found that plasma TG concentrations and TG secretion show a significant day/night rhythm. Next, we removed the daily rhythm in feeding behavior by introducing a 6-meals-a-day (6M) feeding schedule to investigate whether the daily rhythm in feeding behavior is necessary to maintain the daily rhythm in TG secretion. We found that the day/night rhythm in TG secretion was abolished under 6M feeding conditions. Hepatic apolipoprotein B (ApoB) and microsomal TG transfer protein (Mttp), which are both involved in TG secretion, also lost their daily rhythmicity under 6M feeding conditions. Together, these results indicate that: (1) the daily rhythm in TG secretion contributes to the formation of a day/night rhythm in plasma TG levels and (2) a daily feeding rhythm is essential for maintaining the daily rhythm in TG secretion.

  6. Melatonin in sleepless children : everything has a rhythm?

    NARCIS (Netherlands)

    van Geijlswijk, I.M.

    2011-01-01

    Every living organism has an biological clock regulating endogenous melatonin production, synchronized by exogenous impulses like daylight, temperature and feeding. Inappropriately applied bright light disturbs this melatonin rhythm. Some large swine producers apply artificial light three times a

  7. Introduction: circadian rhythm and its disruption: impact on reproductive function.

    Science.gov (United States)

    Casper, Robert F; Gladanac, Bojana

    2014-08-01

    Almost all forms of life have predictable daily or circadian rhythms in molecular, endocrine, and behavioral functions. In mammals, a central pacemaker located in the suprachiasmatic nuclei coordinates the timing of these rhythms. Daily light exposure that affects the retina of the eye directly influences this area, which is required to align endogenous processes to the appropriate time of day. The present "Views and Reviews" articles discuss the influence of circadian rhythms, especially nightly secretion of melatonin, on reproductive function and parturition. In addition, an examination is made of problems that arise from recurrent circadian rhythm disruption associated with changes in light exposure patterns common to modern day society. Finally, a possible solution to prevent disruptions in circadian phase markers by filtering out short wavelengths from nocturnal light is reviewed. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  8. Gamification Quest: Rhythm. Music as a game mechanic

    OpenAIRE

    Granell Díaz, Marina

    2017-01-01

    Treball Final de Grau en Disseny i Desenvolupament de Videojocs. Codi: VJ1241. Curs acadèmic: 2016/2017 This document constitutes the Technical Report for the project Gamification Quest: Rhythm, music as a game mechanic for the Videogame Design and Development bachelor degree. The project consists on the design and implementation of rhythm game mechanics integrated in a gamification environment applied to education. The video game will be implemented on the game engine Unity (10), ...

  9. Using Rhythms of Relationships to Understand Email Archives

    National Research Council Canada - National Science Library

    Perer, Adam; Shneiderman, Ben; Oard, Douglas W

    2005-01-01

    ...: analyzing the temporal rhythms of social relationships. We provide methods for constructing meaningful rhythms from the email headers by identifying relationships and interpreting their attributes. With these visualization techniques, email archive explorers can uncover insights that may have been otherwise hidden in the archive. We apply our methods to an individual's fifteen-year email archive, which consists of about 45,000 messages and over 4,000 relationships.

  10. Human daily rhythms measured for one year.

    Science.gov (United States)

    Binkley, S; Tome, M B; Crawford, D; Mosher, K

    1990-08-01

    Four human subjects recorded their wake-up and to-sleep times for one year each. The data were plotted to display individual circadian rhythms and the data were analyzed statistically. First, individuals had characteristic patterns in which visible changes in the patterns were observed mainly when time zones were changed because of travel. Second, the months with the latest wake-up and latest to-sleep times concentrated around the winter solstice; the months with the earliest wake-up and earliest to-sleep times concentrated around the fall equinox. Third, new moon versus full moon days were not different. Fourth, one-hour changes between standard and daylight savings time in the USA were reflected by near one-hour changes in two subjects, but not in a third. Fifth, weekend delays in wake-up time (0.8-1.6 hours), weekend delays in to-sleep time (0.1-0.5 hours), and shorter weekend awake time (0.8-1.3 hours) were observed. Sixth, throughout the year, wake-up times were close to the time of sunrise, but to-sleep times were several hours past sunset.

  11. Music and speech prosody: a common rhythm.

    Science.gov (United States)

    Hausen, Maija; Torppa, Ritva; Salmela, Viljami R; Vainio, Martti; Särkämö, Teppo

    2013-01-01

    Disorders of music and speech perception, known as amusia and aphasia, have traditionally been regarded as dissociated deficits based on studies of brain damaged patients. This has been taken as evidence that music and speech are perceived by largely separate and independent networks in the brain. However, recent studies of congenital amusia have broadened this view by showing that the deficit is associated with problems in perceiving speech prosody, especially intonation and emotional prosody. In the present study the association between the perception of music and speech prosody was investigated with healthy Finnish adults (n = 61) using an on-line music perception test including the Scale subtest of Montreal Battery of Evaluation of Amusia (MBEA) and Off-Beat and Out-of-key tasks as well as a prosodic verbal task that measures the perception of word stress. Regression analyses showed that there was a clear association between prosody perception and music perception, especially in the domain of rhythm perception. This association was evident after controlling for music education, age, pitch perception, visuospatial perception, and working memory. Pitch perception was significantly associated with music perception but not with prosody perception. The association between music perception and visuospatial perception (measured using analogous tasks) was less clear. Overall, the pattern of results indicates that there is a robust link between music and speech perception and that this link can be mediated by rhythmic cues (time and stress).

  12. Music and speech prosody: A common rhythm

    Directory of Open Access Journals (Sweden)

    Maija eHausen

    2013-09-01

    Full Text Available Disorders of music and speech perception, known as amusia and aphasia, have traditionally been regarded as dissociated deficits based on studies of brain damaged patients. This has been taken as evidence that music and speech are perceived by largely separate and independent networks in the brain. However, recent studies of congenital amusia have broadened this view by showing that the deficit is associated with problems in perceiving speech prosody, especially intonation and emotional prosody. In the present study the association between the perception of music and speech prosody was investigated with healthy Finnish adults (n = 61 using an on-line music perception test including the Scale subtest of Montreal Battery of Evaluation of Amusia (MBEA and Off-Beat and Out-of-key tasks as well as a prosodic verbal task that measures the perception of word stress. Regression analyses showed that there was a clear association between prosody perception and music perception, especially in the domain of rhythm perception. This association was evident after controlling for music education, age, pitch perception, visuospatial perception and working memory. Pitch perception was significantly associated with music perception but not with prosody perception. The association between music perception and visuospatial perception (measured using analogous tasks was less clear. Overall, the pattern of results indicates that there is a robust link between music and speech perception and that this link can be mediated by rhythmic cues (time and stress.

  13. Music and speech prosody: a common rhythm

    Science.gov (United States)

    Hausen, Maija; Torppa, Ritva; Salmela, Viljami R.; Vainio, Martti; Särkämö, Teppo

    2013-01-01

    Disorders of music and speech perception, known as amusia and aphasia, have traditionally been regarded as dissociated deficits based on studies of brain damaged patients. This has been taken as evidence that music and speech are perceived by largely separate and independent networks in the brain. However, recent studies of congenital amusia have broadened this view by showing that the deficit is associated with problems in perceiving speech prosody, especially intonation and emotional prosody. In the present study the association between the perception of music and speech prosody was investigated with healthy Finnish adults (n = 61) using an on-line music perception test including the Scale subtest of Montreal Battery of Evaluation of Amusia (MBEA) and Off-Beat and Out-of-key tasks as well as a prosodic verbal task that measures the perception of word stress. Regression analyses showed that there was a clear association between prosody perception and music perception, especially in the domain of rhythm perception. This association was evident after controlling for music education, age, pitch perception, visuospatial perception, and working memory. Pitch perception was significantly associated with music perception but not with prosody perception. The association between music perception and visuospatial perception (measured using analogous tasks) was less clear. Overall, the pattern of results indicates that there is a robust link between music and speech perception and that this link can be mediated by rhythmic cues (time and stress). PMID:24032022

  14. Circadian rhythm and sleep influences on digestive physiology and disorders

    Directory of Open Access Journals (Sweden)

    Vaughn BV

    2014-09-01

    Full Text Available Bradley V Vaughn, Sean Rotolo, Heidi L Roth Division of Sleep Medicine, Department of Neurology, University of North Carolina School of Medicine, Chapel Hill, NC, USA Abstract: Circadian rhythms and sleep influence a variety of physiological functions, including the digestive system. The digestive system also has intrinsic rhythms that interact dynamically with circadian rhythms. New advances in understanding the interaction of these rhythms and sleep provide the prospect of evaluating their role in normal physiology and the link of their disruption to pathological conditions. Recent work has demonstrated that sleep and circadian factors influence appetite, nutrient absorption, and metabolism. Disruption of sleep and circadian rhythms may increase vulnerability to digestive disorders, including reflux, ulcers, inflammatory bowel issues, irritable bowel disease, and gastrointestinal cancer. As our knowledge of the link between circadian timing and gastrointestinal physiology grows, so do our opportunities to provide promising diagnostic and therapeutic approaches for gastrointestinal disorders. Keywords: digestion, digestive diseases, gastrointestinal reflux, sleep, circadian rhythm 

  15. Educating the sense of rhythm in primary education students

    Directory of Open Access Journals (Sweden)

    Silvia GRĂDINARU

    2017-03-01

    Full Text Available Background: Rhythm as a core element of complex coordination is the key to efficient moulding of motor skills specific to sports activities in curricula. Practicing physical exercise in a varied rhythm and tempo in primary school students moulds the skill of achieving correct movement basics (direction, span, coordination, and expressivity. The use of music in sports classes improves kinetics and vestibular sensitivity. The sense of rhythm and tempo are imperative criteria in vocational schools. Purpose: This paper aims to describe a pattern of means selected to develop the sense of rhythm and to allow movements in different sports branches with increased efficiency. Methods: The test battery was applied on a sample of 15 students from the 4th grade of the “Ion Vidu” National Arts College in Timisoara, Romania, aged 9-10 years, over an entire school year, using different rhythms and tempos during sports classes, which were later used in gymnastics, athletic events, and basketball. Results: Data recorded after the application tests, processed and interpreted confirms the proposed assumption and validates the motor contents used. Conclusions: Sense of rhythm is a component of coordinative capacity that is required to be educated from an early age. Rhythmic movements are easier to automate saving energy and motivating students to an active and conscious participation.

  16. Circadian rhythms in cognitive performance: implications for neuropsychological assessment

    Directory of Open Access Journals (Sweden)

    Valdez P

    2012-12-01

    Full Text Available Pablo Valdez, Candelaria Ramírez, Aída GarcíaLaboratory of Psychophysiology, School of Psychology, University of Nuevo León, Monterrey, Nuevo León, MéxicoAbstract: Circadian variations have been found in human performance, including the efficiency to execute many tasks, such as sensory, motor, reaction time, time estimation, memory, verbal, arithmetic calculations, and simulated driving tasks. Performance increases during the day and decreases during the night. Circadian rhythms have been found in three basic neuropsychological processes (attention, working memory, and executive functions, which may explain oscillations in the performance of many tasks. The time course of circadian rhythms in cognitive performance may be modified significantly in patients with brain disorders, due to chronotype, age, alterations of the circadian rhythm, sleep deprivation, type of disorder, and medication. This review analyzes the recent results on circadian rhythms in cognitive performance, as well as the implications of these rhythms for the neuropsychological assessment of patients with brain disorders such as traumatic head injury, stroke, dementia, developmental disorders, and psychiatric disorders.Keywords: human circadian rhythms, cognitive performance, neuropsychological assessment, attention, working memory, executive functions

  17. Implications of Circadian Rhythm in Dopamine and Mood Regulation.

    Science.gov (United States)

    Kim, Jeongah; Jang, Sangwon; Choe, Han Kyoung; Chung, Sooyoung; Son, Gi Hoon; Kim, Kyungjin

    2017-07-31

    Mammalian physiology and behavior are regulated by an internal time-keeping system, referred to as circadian rhythm. The circadian timing system has a hierarchical organization composed of the master clock in the suprachiasmatic nucleus (SCN) and local clocks in extra-SCN brain regions and peripheral organs. The circadian clock molecular mechanism involves a network of transcription-translation feedback loops. In addition to the clinical association between circadian rhythm disruption and mood disorders, recent studies have suggested a molecular link between mood regulation and circadian rhythm. Specifically, genetic deletion of the circadian nuclear receptor Rev-erbα induces mania-like behavior caused by increased midbrain dopaminergic (DAergic) tone at dusk. The association between circadian rhythm and emotion-related behaviors can be applied to pathological conditions, including neurodegenerative diseases. In Parkinson's disease (PD), DAergic neurons in the substantia nigra pars compacta progressively degenerate leading to motor dysfunction. Patients with PD also exhibit non-motor symptoms, including sleep disorder and neuropsychiatric disorders. Thus, it is important to understand the mechanisms that link the molecular circadian clock and brain machinery in the regulation of emotional behaviors and related midbrain DAergic neuronal circuits in healthy and pathological states. This review summarizes the current literature regarding the association between circadian rhythm and mood regulation from a chronobiological perspective, and may provide insight into therapeutic approaches to target psychiatric symptoms in neurodegenerative diseases involving circadian rhythm dysfunction.

  18. Dynamical Analysis of bantam-Regulated Drosophila Circadian Rhythm Model

    Science.gov (United States)

    Li, Ying; Liu, Zengrong

    MicroRNAs (miRNAs) interact with 3‧untranslated region (UTR) elements of target genes to regulate mRNA stability or translation, and play a crucial role in regulating many different biological processes. bantam, a conserved miRNA, is involved in several functions, such as regulating Drosophila growth and circadian rhythm. Recently, it has been discovered that bantam plays a crucial role in the core circadian pacemaker. In this paper, based on experimental observations, a detailed dynamical model of bantam-regulated circadian clock system is developed to show the post-transcriptional behaviors in the modulation of Drosophila circadian rhythm, in which the regulation of bantam is incorporated into a classical model. The dynamical behaviors of the model are consistent with the experimental observations, which shows that bantam is an important regulator of Drosophila circadian rhythm. The sensitivity analysis of parameters demonstrates that with the regulation of bantam the system is more sensitive to perturbations, indicating that bantam regulation makes it easier for the organism to modulate its period against the environmental perturbations. The effectiveness in rescuing locomotor activity rhythms of mutated flies shows that bantam is necessary for strong and sustained rhythms. In addition, the biological mechanisms of bantam regulation are analyzed, which may help us more clearly understand Drosophila circadian rhythm regulated by other miRNAs.

  19. [Melatonin, synthetic analogs, and the sleep/wake rhythm].

    Science.gov (United States)

    Escames, G; Acuña-Castroviejo, D

    Melatonin, a widespread hormone in the animal kingdom, is produced by several organs and tissues besides the pineal gland. Whilst extrapineal melatonin behaves as a cytoprotective molecule, the pineal produces the hormone in a rhythmic manner. The discovery of melatonin in 1958, and the characterization of its synthesis somewhat later, let to the description of its photoperiodic regulation and its relationship with the biological rhythms such as the sleep/wake rhythm. The suprachiasmatic nuclei are the anatomical seat of the biological clock, represented by the clock genes, which code for the period and frequency of the rhythms. The photoperiod synchronizes the activity of the auprachiasmatic biological clock, which in turn induces the melatonin's rhythm. The rhythm of melatonin, peaking at 2-3 am, acts as an endogenous synchronizer that translates the environmental photoperiodic signal in chemical information for the cells. The sleep/wake cycle is a typical biological rhythm synchronized by melatonin, and the sleep/wake cycle alterations of chronobiological origin, are very sensitive to melatonin treatment. Taking advantage of the chronobiotic and antidepressive properties of melatonin, a series of synthetic analogs of this hormone, with high interest in insomnia, are now available. Melatonin is a highly effective chronobiotic in the treatment of chronobiological alterations of the sleep/wake cycle. From a pharmacokinetic point of view, the synthetic drugs derived from melatonin are interesting tools in the therapy of these alterations.

  20. Physical Attractiveness and Courtship

    Science.gov (United States)

    Silverman, Irwin

    1971-01-01

    This study shows a high and disquieting degree of similarity in physical attractiveness between dating partners, and suggests also that more similar partners tend to form stronger romantic attachments. (Author)

  1. Courtship in Frogs

    Indian Academy of Sciences (India)

    well-defined physical characteristics and a clear biological meaning. ... men t most successfully were the frogs and toads (hereafter referred ... Sound Pressure Level (SPL) in decibels = 20 loglOPt/Pr where,. Pt is the .... R.erythraea (left) and mean spectrum and sonagram of the female ... and egg laying activities initiated. 5.

  2. Reducing language to rhythm: Amazonian Bora drummed language exploits speech rhythm for long-distance communication

    Science.gov (United States)

    Seifart, Frank; Meyer, Julien; Grawunder, Sven; Dentel, Laure

    2018-04-01

    Many drum communication systems around the world transmit information by emulating tonal and rhythmic patterns of spoken languages in sequences of drumbeats. Their rhythmic characteristics, in particular, have not been systematically studied so far, although understanding them represents a rare occasion for providing an original insight into the basic units of speech rhythm as selected by natural speech practices directly based on beats. Here, we analyse a corpus of Bora drum communication from the northwest Amazon, which is nowadays endangered with extinction. We show that four rhythmic units are encoded in the length of pauses between beats. We argue that these units correspond to vowel-to-vowel intervals with different numbers of consonants and vowel lengths. By contrast, aligning beats with syllables, mora or only vowel length yields inconsistent results. Moreover, we also show that Bora drummed messages conventionally select rhythmically distinct markers to further distinguish words. The two phonological tones represented in drummed speech encode only few lexical contrasts. Rhythm thus appears to crucially contribute to the intelligibility of drummed Bora. Our study provides novel evidence for the role of rhythmic structures composed of vowel-to-vowel intervals in the complex puzzle concerning the redundancy and distinctiveness of acoustic features embedded in speech.

  3. The role of the daily feeding rhythm in the regulation of the day/night rhythm in triglyceride secretion in rats

    NARCIS (Netherlands)

    Su, Yan; Foppen, Ewout; Mansur Machado, Frederico Sander; Fliers, Eric; Kalsbeek, A.

    2018-01-01

    Plasma triglyceride (TG) levels show a clear daily rhythm, however, thus far it is still unknown whether this rhythm results from a daily rhythm in TG production, TG uptake or both. Previous studies have shown that feeding activity affects plasma TG concentrations, but it is not clear how the daily

  4. Cortical layers, rhythms and BOLD signals.

    Science.gov (United States)

    Scheeringa, René; Fries, Pascal

    2017-11-03

    This review investigates how laminar fMRI can complement insights into brain function derived from the study of rhythmic neuronal synchronization. Neuronal synchronization in various frequency bands plays an important role in neuronal communication between brain areas, and it does so on the backbone of layer-specific interareal anatomical projections. Feedforward projections originate predominantly in supragranular cortical layers and terminate in layer 4, and this pattern is reflected in inter-laminar and interareal directed gamma-band influences. Thus, gamma-band synchronization likely subserves feedforward signaling. By contrast, anatomical feedback projections originate predominantly in infragranular layers and terminate outside layer 4, and this pattern is reflected in inter-laminar and interareal directed alpha- and/or beta-band influences. Thus, alpha-beta band synchronization likely subserves feedback signaling. Furthermore, these rhythms explain part of the BOLD signal, with independent contributions of alpha-beta and gamma. These findings suggest that laminar fMRI can provide us with a potentially useful method to test some of the predictions derived from the study of neuronal synchronization. We review central findings regarding the role of layer-specific neuronal synchronization for brain function, and regarding the link between neuronal synchronization and the BOLD signal. We discuss the role that laminar fMRI could play by comparing it to invasive and non-invasive electrophysiological recordings. Compared to direct electrophysiological recordings, this method provides a metric of neuronal activity that is slow and indirect, but that is uniquely non-invasive and layer-specific with potentially whole brain coverage. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  5. Physiological basis for human autonomic rhythms

    Science.gov (United States)

    Eckberg, D. L.

    2000-01-01

    Oscillations of arterial pressures, heart periods, and muscle sympathetic nerve activity have been studied intensively in recent years to explore otherwise obscure human neurophysiological mechanisms. The best-studied rhythms are those occurring at breathing frequencies. Published evidence indicates that respiratory fluctuations of muscle sympathetic nerve activity and electrocardiographic R-R intervals result primarily from the action of a central 'gate' that opens during expiration and closes during inspiration. Parallel respiratory fluctuations of arterial pressures and R-R intervals are thought to be secondary to arterial baroreflex physiology: changes in systolic pressure provoke changes in the R-R interval. However, growing evidence suggests that these parallel oscillations result from the influence of respiration on sympathetic and vagal-cardiac motoneurones rather than from baroreflex physiology. There is a rapidly growing literature on the use of mathematical models of low- and high-frequency (respiratory) R-R interval fluctuations in characterizing instantaneous 'sympathovagal balance'. The case for this approach is based primarily on measurements made with patients in upright tilt. However, the strong linear relation between such measures as the ratio of low- to high-frequency R-R interval oscillations and the angle of the tilt reflects exclusively the reductions of the vagal (high-frequency) component. As the sympathetic component does not change in tilt, the low- to high-frequency R-R interval ratio provides no proof that sympathetic activity increases. Moreover, the validity of extrapolating from measurements performed during upright tilt to measurements during supine rest has not been established. Nonetheless, it is clear that measures of heart rate variability provide important prognostic information in patients with cardiovascular diseases. It is not known whether reduced heart rate variability is merely a marker for the severity of disease or a

  6. Circadian Rhythms in Floral Scent Emission.

    Science.gov (United States)

    Fenske, Myles P; Imaizumi, Takato

    2016-01-01

    To successfully recruit pollinators, plants often release attractive floral scents at specific times of day to coincide with pollinator foraging. This timing of scent emission is thought to be evolutionarily beneficial to maximize resource efficiency while attracting only useful pollinators. Temporal regulation of scent emission is tied to the activity of the specific metabolic pathways responsible for scent production. Although floral volatile profiling in various plants indicated a contribution by the circadian clock, the mechanisms by which the circadian clock regulates timing of floral scent emission remained elusive. Recent studies using two species in the Solanaceae family provided initial insight into molecular clock regulation of scent emission timing. In Petunia hybrida, the floral volatile benzenoid/phenylpropanoid (FVBP) pathway is the major metabolic pathway that produces floral volatiles. Three MYB-type transcription factors, ODORANT 1 (ODO1), EMISSION OF BENZENOIDS I (EOBI), and EOBII, all of which show diurnal rhythms in mRNA expression, act as positive regulators for several enzyme genes in the FVBP pathway. Recently, in P. hybrida and Nicotiana attenuata, homologs of the Arabidopsis clock gene LATE ELONGATED HYPOCOTYL (LHY) have been shown to have a similar role in the circadian clock in these plants, and to also determine the timing of scent emission. In addition, in P. hybrida, PhLHY directly represses ODO1 and several enzyme genes in the FVBP pathway during the morning as an important negative regulator of scent emission. These findings facilitate our understanding of the relationship between a molecular timekeeper and the timing of scent emission, which may influence reproductive success.

  7. Circadian rhythms in floral scent emission

    Directory of Open Access Journals (Sweden)

    Myles eFenske

    2016-04-01

    Full Text Available To successfully recruit pollinators, plants often release attractive floral scents at specific times of day to coincide with pollinator foraging. This timing of scent emission is thought to be evolutionarily beneficial to maximize resource efficiency while attracting only useful pollinators. Temporal regulation of scent emission is tied to the activity of the specific metabolic pathways responsible for scent production. Although floral volatile profiling in various plants indicated a contribution by the circadian clock, the mechanisms by which the circadian clock regulates timing of floral scent emission remained elusive. Recent studies using two species in the Solanaceae family provided initial insight into molecular clock regulation of scent emission timing. In Petunia hybrida, the benzenoid/phenylpropanoid (FVBP pathway is the major metabolic pathway that produces floral volatiles. Three MYB-type transcription factors, ODORANT1 (ODO1, EMISSION OF BENZENOIDS I (EOBI, and EOBII, all of which show diurnal rhythms in mRNA expression, act as positive regulators for several enzyme genes in the FVBP pathway. Recently, in P. hybrida and Nicotiana attenuata, homologs of the Arabidopsis clock gene LATE ELONGATED HYPOCOTYL (LHY have been shown to have a similar role in the circadian clock in these plants, and to also determine the timing of scent emission. In addition, in P. hybrida, PhLHY directly represses ODO1 and several enzyme genes in the FVBP pathway during the morning as an important negative regulator of scent emission. These findings facilitate our understanding of the relationship between a molecular timekeeper and the timing of scent emission, which may influence reproductive success.

  8. [Psychoeducation and interpersonal and social rhythm therapy for bipolar disorder].

    Science.gov (United States)

    Mizushima, Hiroko

    2011-01-01

    In treating bipolar disorder, specific psychotherapies in adjunct to pharmacotherapy have been shown to be effective in preventing new episodes and treating depressive episodes. Among those, interpersonal and social rhythm therapy (IPSRT) developed by Frank, amalgamation of interpersonal psychotherapy (IPT) with behavioral therapy focused on social rhythm has been shown to be an efficacious adjunct to mediation in preventing new episodes in bipolar I patients and in treating depression in bipolar I arid II disorder. IPSRT has also been shown to enhance total functioning, relationship functioning and life satisfaction among patients with bipolar disorder, even after pretreatment functioning and concurrent depression were covaried. IPSRT was designed to directly address the major pathways to recurrence in bipolar disorder, namely medication nonadherence, stressful life events, and disruptions in social rhythms. IPT, originated by Klerman et al., is a strategic time-limited psychotherapy focused on one or two of four current interpersonal problem areas (ie, grief, interpersonal role disputes, role transitions, and interpersonal dificits). In IPSRT, the fifth problem area "grief for the lost healthy self" has been added in order to promote acceptance of the diagnosis and the need for life-long treatment. Social rhythm therapy is a behavioral approach aiming at increasing regularity of social rhythms using the Social Rhythm Metric (SRM), a chart to record daily social activities including how stimulating they were, developed from observation that disruptions in social rhythms often trigger affective episodes in patients with bipolar disorder. IPSRT also appears to be a promising intervention for a subset of individuals with bipolar II depression as monotherapy for the acute treatment.

  9. Rhythms of mammalian body temperature can sustain peripheral circadian clocks.

    Science.gov (United States)

    Brown, Steven A; Zumbrunn, Gottlieb; Fleury-Olela, Fabienne; Preitner, Nicolas; Schibler, Ueli

    2002-09-17

    Low-amplitude temperature oscillations can entrain the phase of circadian rhythms in several unicellular and multicellular organisms, including Neurospora and Drosophila. Because mammalian body temperature is subject to circadian variations of 1 degrees C-4 degrees C, we wished to determine whether these temperature cycles could serve as a Zeitgeber for circadian gene expression in peripheral cell types. In RAT1 fibroblasts cultured in vitro, circadian gene expression could be established by a square wave temperature rhythm with a (Delta)T of 4 degrees C (12 hr 37 degrees C/12 hr 33 degrees C). To examine whether natural body temperature rhythms can also affect circadian gene expression, we first measured core body temperature cycles in the peritoneal cavities of mice by radiotelemetry. We then reproduced these rhythms with high precision in the liquid medium of cultured fibroblasts for several days by means of a homemade computer-driven incubator. While these "in vivo" temperature rhythms were incapable of establishing circadian gene expression de novo, they could maintain previously induced rhythms for multiple days; by contrast, the rhythms of control cells kept at constant temperature rapidly dampened. Moreover, circadian oscillations of environmental temperature could reentrain circadian clocks in the livers of mice, probably via the changes they imposed upon both body temperature and feeding behavior. Interestingly, these changes in ambient temperature did not affect the phase of the central circadian pacemaker in the suprachiasmatic nucleus (SCN) of the hypothalamus. We postulate that both endogenous and environmental temperature cycles can participate in the synchronization of peripheral clocks in mammals.

  10. Are circadian rhythms new pathways to understand Autism Spectrum Disorder?

    Science.gov (United States)

    Geoffray, M-M; Nicolas, A; Speranza, M; Georgieff, N

    2016-11-01

    Autism Spectrum Disorder (ASD) is a frequent neurodevelopmental disorder. ASD is probably the result of intricate interactions between genes and environment altering progressively the development of brain structures and functions. Circadian rhythms are a complex intrinsic timing system composed of almost as many clocks as there are body cells. They regulate a variety of physiological and behavioral processes such as the sleep-wake rhythm. ASD is often associated with sleep disorders and low levels of melatonin. This first point raises the hypothesis that circadian rhythms could have an implication in ASD etiology. Moreover, circadian rhythms are generated by auto-regulatory genetic feedback loops, driven by transcription factors CLOCK and BMAL1, who drive transcription daily patterns of a wide number of clock-controlled genes (CCGs) in different cellular contexts across tissues. Among these, are some CCGs coding for synapses molecules associated to ASD susceptibility. Furthermore, evidence emerges about circadian rhythms control of time brain development processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Rhythms in the endocrine system of fish: a review.

    Science.gov (United States)

    Cowan, Mairi; Azpeleta, Clara; López-Olmeda, Jose Fernando

    2017-12-01

    The environment which living organisms inhabit is not constant and many factors, such as light, temperature, and food availability, display cyclic and predictable variations. To adapt to these cyclic changes, animals present biological rhythms in many of their physiological variables, timing their functions to occur when the possibility of success is greatest. Among these variables, many endocrine factors have been described as displaying rhythms in vertebrates. The aim of the present review is to provide a thorough review of the existing knowledge on the rhythms of the endocrine system of fish by examining the hormones that show rhythmicity, how environmental factors control these rhythms and the variation in the responses of the endocrine system depending on the time of the day. We mainly focused on the hypothalamic-pituitary axis, which can be considered as the master axis of the endocrine system of vertebrates and regulates a great variety of functions, including reproduction, growth, metabolism, energy homeostasis, stress response, and osmoregulation. In addition, the rhythms of other hormones, such as melatonin and the factors, produced in the gastrointestinal system of fish are reviewed.

  12. Intracerebral evidence of rhythm transform in the human auditory cortex.

    Science.gov (United States)

    Nozaradan, Sylvie; Mouraux, André; Jonas, Jacques; Colnat-Coulbois, Sophie; Rossion, Bruno; Maillard, Louis

    2017-07-01

    Musical entrainment is shared by all human cultures and the perception of a periodic beat is a cornerstone of this entrainment behavior. Here, we investigated whether beat perception might have its roots in the earliest stages of auditory cortical processing. Local field potentials were recorded from 8 patients implanted with depth-electrodes in Heschl's gyrus and the planum temporale (55 recording sites in total), usually considered as human primary and secondary auditory cortices. Using a frequency-tagging approach, we show that both low-frequency (30 Hz) neural activities in these structures faithfully track auditory rhythms through frequency-locking to the rhythm envelope. A selective gain in amplitude of the response frequency-locked to the beat frequency was observed for the low-frequency activities but not for the high-frequency activities, and was sharper in the planum temporale, especially for the more challenging syncopated rhythm. Hence, this gain process is not systematic in all activities produced in these areas and depends on the complexity of the rhythmic input. Moreover, this gain was disrupted when the rhythm was presented at fast speed, revealing low-pass response properties which could account for the propensity to perceive a beat only within the musical tempo range. Together, these observations show that, even though part of these neural transforms of rhythms could already take place in subcortical auditory processes, the earliest auditory cortical processes shape the neural representation of rhythmic inputs in favor of the emergence of a periodic beat.

  13. Social Rhythm and Mental Health: A Cross-Cultural Comparison.

    Directory of Open Access Journals (Sweden)

    Jürgen Margraf

    Full Text Available Social rhythm refers to the regularity with which one engages in social activities throughout the week, and has established links with bipolar disorder, as well as some links with depression and anxiety. The aim of the present study is to examine social rhythm and its relationship to various aspects of health, including physical health, negative mental health, and positive mental health.Questionnaire data were obtained from a large-scale multi-national sample of 8095 representative participants from the U.S., Russia, and Germany.Results indicated that social rhythm irregularity is related to increased reporting of health problems, depression, anxiety, and stress. In contrast, greater regularity is related to better overall health state, life satisfaction, and positive mental health. The effects are generally small in size, but hold even when controlling for gender, marital status, education, income, country, and social support. Further, social rhythm means differ across Russia, the U.S., and Germany. Relationships with mental health are present in all three countries, but differ in magnitude.Social rhythm irregularity is related to mental health in Russia, the U.S., and Germany.

  14. A microsatellite linkage map for Drosophila montana shows large variation in recombination rates, and a courtship song trait maps to an area of low recombination.

    Science.gov (United States)

    Schäfer, M A; Mazzi, D; Klappert, K; Kauranen, H; Vieira, J; Hoikkala, A; Ritchie, M G; Schlötterer, C

    2010-03-01

    Current advances in genetic analysis are opening up our knowledge of the genetics of species differences, but challenges remain, particularly for out-bred natural populations. We constructed a microsatellite-based linkage map for two out-bred lines of Drosophila montana derived from divergent populations by taking advantage of the Drosophila virilis genome and available cytological maps of both species. Although the placement of markers was quite consistent with cytological predictions, the map indicated large heterogeneity in recombination rates along chromosomes. We also performed a quantitative trait locus (QTL) analysis on a courtship song character (carrier frequency), which differs between populations and is subject to strong sexual selection. Linkage mapping yielded two significant QTLs, which explained 3% and 14% of the variation in carrier frequency, respectively. Interestingly, as in other recent studies of traits which can influence speciation, the strongest QTL mapped to a genomic region partly covered by an inversion polymorphism.

  15. Male-typical courtship, spawning behavior, and olfactory sensitivity are induced to different extents by androgens in the goldfish suggesting they are controlled by different neuroendocrine mechanisms.

    Science.gov (United States)

    Ghosal, Ratna; Sorensen, Peter W

    2016-06-01

    Male-typical reproductive behaviors vary greatly between different species of fishes with androgens playing a variety of roles that appear especially important in the gonochorist cypriniform fishes. The goldfish is an important model for the cypriniformes and while it is clear that male goldfish are fully feminized by prostaglandin F2α(PGF2α), it is not clear whether females will exhibit normal levels of male-typical reproductive behaviors as well as olfactory function when treated with androgens. To answer this question, we exposed sexually-regressed adult female goldfish to several types of androgen and monitored their tendencies to court (inspect females) and mate (spawn, or attempt to release gametes) while monitoring their olfactory sensitivity until changes in these attributes were maximized. Untreated adult males (intact) were included to determine the extent of masculinization. Treatments included the natural androgens, 11-ketotestosterone and testosterone (KT and T), administered via capsules (KT+T-implanted fish); the artificial androgen, methyltestosterone (MT), administered via capsules (MT-C); and MT administered in the fishes' water (MT-B). Male-typical olfactory sensitivity to a pheromone (15keto-PGF2α) increased in all androgen-treated groups and by week 6 was fully equivalent to that of males. Male-typical courtship behavior increased in all androgen-treated groups although slowly, and only MT-B females came to exhibit levels equivalent to those of males after 18weeks. In contrast, male-typical mating activity increased only slightly, with MT-B females reaching levels one-third that of males after 30weeks. We conclude that while androgens fully masculinize olfactory sensitivity and courtship behavior in goldfish, mating behavior is controlled by a different neuroendocrine mechanism(s) that has yet to be fully elucidated. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Sleep and circadian rhythm disruption in neuropsychiatric illness.

    Science.gov (United States)

    Jagannath, Aarti; Peirson, Stuart N; Foster, Russell G

    2013-10-01

    Sleep and circadian rhythm disruption (SCRD) is a common feature in many neuropsychiatric diseases including schizophrenia, bipolar disorder and depression. Although the precise mechanisms remain unclear, recent evidence suggests that this comorbidity is not simply a product of medication or an absence of social routine, but instead reflects commonly affected underlying pathways and mechanisms. For example, several genes intimately involved in the generation and regulation of circadian rhythms and sleep have been linked to psychiatric illness. Further, several genes linked to mental illness have recently been shown to also play a role in normal sleep and circadian behaviour. Here we describe some of the emerging common mechanisms that link circadian rhythms, sleep and SCRD in severe mental illnesses. A deeper understanding of these links will provide not only a greater understanding of disease mechanisms, but also holds the promise of novel avenues for therapeutic intervention. Copyright © 2013. Published by Elsevier Ltd.

  17. Circadian rhythms, time-restricted feeding, and healthy aging.

    Science.gov (United States)

    Manoogian, Emily N C; Panda, Satchidananda

    2017-10-01

    Circadian rhythms optimize physiology and health by temporally coordinating cellular function, tissue function, and behavior. These endogenous rhythms dampen with age and thus compromise temporal coordination. Feeding-fasting patterns are an external cue that profoundly influence the robustness of daily biological rhythms. Erratic eating patterns can disrupt the temporal coordination of metabolism and physiology leading to chronic diseases that are also characteristic of aging. However, sustaining a robust feeding-fasting cycle, even without altering nutrition quality or quantity, can prevent or reverse these chronic diseases in experimental models. In humans, epidemiological studies have shown erratic eating patterns increase the risk of disease, whereas sustained feeding-fasting cycles, or prolonged overnight fasting, is correlated with protection from breast cancer. Therefore, optimizing the timing of external cues with defined eating patterns can sustain a robust circadian clock, which may prevent disease and improve prognosis. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Recent Advances in Circadian Rhythms in Cardiovascular System

    Directory of Open Access Journals (Sweden)

    Lihong eChen

    2015-04-01

    Full Text Available Growing evidence shows that intrinsic circadian clocks are tightly related to cardiovascular functions. The diurnal changes in blood pressure and heart rate are well known circadian rhythms. Endothelial function, platelet aggregation and thrombus formation exhibit circadian changes as well. The onset of many cardiovascular diseases (CVDs or events, such as myocardial infarction, stroke, arrhythmia, and sudden cardiac death, also exhibits temporal trends. Furthermore, there is strong evidence from animal models and epidemiological studies showing that disruption of circadian rhythms is a significant risk factor for many CVDs, and the intervention of CVDs may have a time dependent effect. In this mini review, we summarized recent advances in our understanding of the relationship between circadian rhythm and cardiovascular physiology and diseases including blood pressure regulation and myocardial infarction.

  19. Circadian Rhythm Sleep-Wake Disorders in Older Adults.

    Science.gov (United States)

    Kim, Jee Hyun; Duffy, Jeanne F

    2018-03-01

    The timing, duration, and consolidation of sleep result from the interaction of the circadian timing system with a sleep-wake homeostatic process. When aligned and functioning optimally, this allows wakefulness throughout the day and a long consolidated sleep episode at night. Mismatch between the desired timing of sleep and the ability to fall and remain asleep is a hallmark of the circadian rhythm sleep-wake disorders. This article discusses changes in circadian regulation of sleep with aging; how age influences the prevalence, diagnosis, and treatment of circadian rhythm sleep-wake disorders; and how neurologic diseases in older patients affect circadian rhythms and sleep. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Core temperature rhythms in normal and tumor-bearing mice.

    Science.gov (United States)

    Griffith, D J; Busot, J C; Lee, W E; Djeu, D J

    1993-01-01

    The core temperature temporal behavior of DBA/2 mice (11 normal and 13 with an ascites tumor) was studied using surgically implanted radio telemetry transmitters. Normal mice continuously displayed a stable 24 hour temperature rhythm. Tumor-bearers displayed a progressive deterioration of the temperature rhythm following inoculation with tumor cells. While such disruptions have been noted by others, details on the dynamics of the changes have been mostly qualitative, often due to time-averaging or steady-state analysis of the data. The present study attempts to quantify the dynamics of the disruption of temperature rhythm (when present) by continuously monitoring temperatures over periods up to a month. Analysis indicated that temperature regulation in tumor-bearers was adversely affected during the active period only. Furthermore, it appears that the malignancy may be influencing temperature regulation via pathways not directly attributable to the energy needs of the growing tumor.

  1. Current Conceptual Challenges in the Study of Rhythm Processing Deficits

    Directory of Open Access Journals (Sweden)

    Pauline eTranchant

    2015-06-01

    Full Text Available Interest in the study of rhythm processing deficits (RPD is currently growing in the cognitive neuroscience community, as this type of investigation constitutes a powerful tool for the understanding of normal rhythm processing. Because this field is in its infancy, it still lacks a common conceptual vocabulary to facilitate effective communication between different researchers and research groups. In this commentary, we provide a brief review of recent reports of RPD through the lens of one important empirical issue: the method by which beat perception is measured, and the consequences of method selection for the researcher’s ability to specify which mechanisms are impaired in RPD. This critical reading advocates for the importance of matching measurement tools to the putative neurocognitive mechanisms under study, and reveals the need for effective and specific assessments of the different aspects of rhythm perception and synchronization.

  2. Rhythm information represented in the fronto-parieto-cerebellar motor system.

    Science.gov (United States)

    Konoike, Naho; Kotozaki, Yuka; Miyachi, Shigehiro; Miyauchi, Carlos Makoto; Yomogida, Yukihito; Akimoto, Yoritaka; Kuraoka, Koji; Sugiura, Motoaki; Kawashima, Ryuta; Nakamura, Katsuki

    2012-10-15

    Rhythm is an essential element of human culture, particularly in language and music. To acquire language or music, we have to perceive the sensory inputs, organize them into structured sequences as rhythms, actively hold the rhythm information in mind, and use the information when we reproduce or mimic the same rhythm. Previous brain imaging studies have elucidated brain regions related to the perception and production of rhythms. However, the neural substrates involved in the working memory of rhythm remain unclear. In addition, little is known about the processing of rhythm information from non-auditory inputs (visual or tactile). Therefore, we measured brain activity by functional magnetic resonance imaging while healthy subjects memorized and reproduced auditory and visual rhythmic information. The inferior parietal lobule, inferior frontal gyrus, supplementary motor area, and cerebellum exhibited significant activations during both encoding and retrieving rhythm information. In addition, most of these areas exhibited significant activation also during the maintenance of rhythm information. All of these regions functioned in the processing of auditory and visual rhythms. The bilateral inferior parietal lobule, inferior frontal gyrus, supplementary motor area, and cerebellum are thought to be essential for motor control. When we listen to a certain rhythm, we are often stimulated to move our body, which suggests the existence of a strong interaction between rhythm processing and the motor system. Here, we propose that rhythm information may be represented and retained as information about bodily movements in the supra-modal motor brain system. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Circadian melatonin rhythm and excessive daytime sleepiness in Parkinson disease.

    Science.gov (United States)

    Videnovic, Aleksandar; Noble, Charleston; Reid, Kathryn J; Peng, Jie; Turek, Fred W; Marconi, Angelica; Rademaker, Alfred W; Simuni, Tanya; Zadikoff, Cindy; Zee, Phyllis C

    2014-04-01

    Diurnal fluctuations of motor and nonmotor symptoms and a high prevalence of sleep-wake disturbances in Parkinson disease (PD) suggest a role of the circadian system in the modulation of these symptoms. However, surprisingly little is known regarding circadian function in PD and whether circadian dysfunction is involved in the development of sleep-wake disturbances in PD. To determine the relationship between the timing and amplitude of the 24-hour melatonin rhythm, a marker of endogenous circadian rhythmicity, with self-reported sleep quality, the severity of daytime sleepiness, and disease metrics. A cross-sectional study from January 1, 2009, through December 31, 2012, of 20 patients with PD receiving stable dopaminergic therapy and 15 age-matched control participants. Both groups underwent blood sampling for the measurement of serum melatonin levels at 30-minute intervals for 24 hours under modified constant routine conditions at the Parkinson's Disease and Movement Disorders Center of Northwestern University. Twenty-four hour monitoring of serum melatonin secretion. Clinical and demographic data, self-reported measures of sleep quality (Pittsburgh Sleep Quality Index) and daytime sleepiness (Epworth Sleepiness Scale), and circadian markers of the melatonin rhythm, including the amplitude, area under the curve (AUC), and phase of the 24-hour rhythm. Patients with PD had blunted circadian rhythms of melatonin secretion compared with controls; the amplitude of the melatonin rhythm and the 24-hour AUC for circulating melatonin levels were significantly lower in PD patients (P hour melatonin AUC (P = .001). Disease duration, Unified Parkinson's Disease Rating Scale scores, levodopa equivalent dose, and global Pittsburgh Sleep Quality Index score in the PD group were not significantly related to measures of the melatonin circadian rhythm. Circadian dysfunction may underlie excessive sleepiness in PD. The nature of this association needs to be explored further

  4. Is there an endogenous tidal foraging rhythm in marine iguanas?

    Science.gov (United States)

    Wikelski, M; Hau, M

    1995-12-01

    As strictly herbivorous reptiles, Galápagos marine iguanas graze on algae in the intertidal areas during low tide. Daily foraging rhythms were observed on two islands during 3 years to determine the proximate factors underlying behavioral synchrony with the tides. Marine iguanas walked to their intertidal foraging grounds from far-off resting areas in anticipation of the time of low tide. Foraging activity was restricted to daytime, resulting in a complex bitidal rhythm including conspicuous switches from afternoon foraging to foraging during the subsequent morning when low tide occurred after dusk. The animals anticipated the daily low tide by a maximum of 4 h. The degree of anticipation depended on environmental parameters such as wave action and food supply. "Early foragers" survived in greater numbers than did animals arriving later at foraging sites, a result indicating selection pressure on the timing of anticipation. The timing of foraging trips was better predicted by the daily changes in tabulated low tide than it was by the daily changes in actual exposure of the intertidal foraging flats, suggesting an endogenous nature of the foraging rhythms. Endogenous rhythmicity would also explain why iguanas that had spontaneously fasted for several days nevertheless went foraging at the "right" time of day. A potential lunar component of the foraging rhythmicity of marine iguanas showed up in their assemblage on intertidal rocks during neap tide nights. This may indicate that iguanas possessed information on the semi-monthly rhythms in tide heights. Enclosure experiments showed that bitidal foraging rhythms of iguanas may free run in the absence of direct cues from the intertidal areas and operate independent of the light:dark cycle and social stimuli. Therefore, the existence of a circatidal oscillator in marine iguanas is proposed. The bitidal foraging pattern may result from an interaction of a circadian system with a circatidal system. Food intake or related

  5. Rhythm generation through period concatenation in rat somatosensory cortex.

    Directory of Open Access Journals (Sweden)

    Mark A Kramer

    2008-09-01

    Full Text Available Rhythmic voltage oscillations resulting from the summed activity of neuronal populations occur in many nervous systems. Contemporary observations suggest that coexistent oscillations interact and, in time, may switch in dominance. We recently reported an example of these interactions recorded from in vitro preparations of rat somatosensory cortex. We found that following an initial interval of coexistent gamma ( approximately 25 ms period and beta2 ( approximately 40 ms period rhythms in the superficial and deep cortical layers, respectively, a transition to a synchronous beta1 ( approximately 65 ms period rhythm in all cortical layers occurred. We proposed that the switch to beta1 activity resulted from the novel mechanism of period concatenation of the faster rhythms: gamma period (25 ms+beta2 period (40 ms = beta1 period (65 ms. In this article, we investigate in greater detail the fundamental mechanisms of the beta1 rhythm. To do so we describe additional in vitro experiments that constrain a biologically realistic, yet simplified, computational model of the activity. We use the model to suggest that the dynamic building blocks (or motifs of the gamma and beta2 rhythms combine to produce a beta1 oscillation that exhibits cross-frequency interactions. Through the combined approach of in vitro experiments and mathematical modeling we isolate the specific components that promote or destroy each rhythm. We propose that mechanisms vital to establishing the beta1 oscillation include strengthened connections between a population of deep layer intrinsically bursting cells and a transition from antidromic to orthodromic spike generation in these cells. We conclude that neural activity in the superficial and deep cortical layers may temporally combine to generate a slower oscillation.

  6. Circadian Rhythm Connections to Oxidative Stress: Implications for Human Health

    Science.gov (United States)

    Wilking, Melissa; Ndiaye, Mary; Mukhtar, Hasan

    2013-01-01

    Abstract Significance: Oxygen and circadian rhythmicity are essential in a myriad of physiological processes to maintain homeostasis, from blood pressure and sleep/wake cycles, down to cellular signaling pathways that play critical roles in health and disease. If the human body or cells experience significant stress, their ability to regulate internal systems, including redox levels and circadian rhythms, may become impaired. At cellular as well as organismal levels, impairment in redox regulation and circadian rhythms may lead to a number of adverse effects, including the manifestation of a variety of diseases such as heart diseases, neurodegenerative conditions, and cancer. Recent Advances: Researchers have come to an understanding as to the basics of the circadian rhythm mechanism, as well as the importance of the numerous species of oxidative stress components. The effects of oxidative stress and dysregulated circadian rhythms have been a subject of intense investigations since they were first discovered, and recent investigations into the molecular mechanisms linking the two have started to elucidate the bases of their connection. Critical Issues: While much is known about the mechanics and importance of oxidative stress systems and circadian rhythms, the front where they interact has had very little research focused on it. This review discusses the idea that these two systems are together intricately involved in the healthy body, as well as in disease. Future Directions: We believe that for a more efficacious management of diseases that have both circadian rhythm and oxidative stress components in their pathogenesis, targeting both systems in tandem would be far more successful. Antioxid. Redox Signal. 19, 192–208 PMID:23198849

  7. A circadian rhythm of conidiation in Neurospora crassa (L-12)

    Science.gov (United States)

    Miyoshi, Yashuhiro

    1993-01-01

    Two fungi growth chambers containing six growth tubes each are used in this experiment. One chamber is for the space experiment; the other is for the simultaneous ground control experiment. The hyphae of Neurospora crassa band A mutant are inoculated at one end of each tube. Both the chambers are kept at 3 C plus or minus 1.5 C to stop hyphae growth until the Spacelab is activated. After the activation, each chamber is transferred simultaneously to the Spacelab and a phytotron in KSC and kept in continuous light at the same temperature. After about 24 hours of light exposure, each chamber is inserted into a growth chamber bag to keep it in constant darkness. The circadian rhythm of conidiation is initiated by this light to dark transition. After the dark incubation for 5 days at room temperature, both the growth chambers are kept at 3 C plus or minus 1.5 C to stop growth of the hyphae. After the space shuttle lands, both conidiation patterns are compared and analyzed. It has been known that numerous physiological phenomena show circadian rhythms. They are characterized by the fact that the oscillation can persist under constant conditions of light and temperature. Therefore, it has been accepted by most investigators that the generation mechanism of the circadian rhythm is endogeneous. However, one cannot reject the possibility that these rhythms are caused by some geophysical exogeneous factor having a 24-hour period, such as atmospheric pressure, gravity, or electromagnetic radiation. We use Neurospora crassa band A mutual which shows an obvious circadian rhythm in its spore-forming (conidiation) on the ground, and we intend to attempt the conidation of this mutant in the Spacelab where 24-hour periodicity is severely attenuated and to elucidate the effect of the geophysical exogeneous factor in the generation mechanism of the circadian rhythm.

  8. Circadian rhythm of temperature selection in a nocturnal lizard.

    Science.gov (United States)

    Refinetti, R; Susalka, S J

    1997-08-01

    We recorded body temperature and locomotor activity of Tokay geckos (Gekko gecko) with free access to a heat source under a 14:10 light-dark cycle and in constant darkness. Under the light-dark cycle, the lizards selected higher temperatures during the light phase, when locomotor activity was less intense. Rhythmicity in temperature selection was transiently disrupted but later resumed when the animals were placed in constant darkness. These results demonstrate the existence of a circadian rhythm of temperature selection in nocturnal ectotherms and extend previous findings of a temporal mismatch between the rhythms of locomotor activity and temperature selection in nocturnal rodents.

  9. Meditations on the unitary rhythm of dying-grieving.

    Science.gov (United States)

    Malinski, Violet M

    2012-07-01

    When someone faces loss of a loved one, that person simultaneously grieves and dies a little, just as the one dying also grieves. The author's personal conceptualization of dying and grieving as a unitary rhythm is explored based primarily on her interpretation of Rogers' science of unitary human beings, along with selected examples from related nursing literature and from the emerging focus on continuing bonds in other disciplines. Examples from contemporary songwriters that depict such a unitary conceptualization are given along with personal examples. The author concludes with her description of the unitary rhythm of dying-grieving.

  10. Rhythm-based segmentation of Popular Chinese Music

    DEFF Research Database (Denmark)

    Jensen, Karl Kristoffer

    2005-01-01

    We present a new method to segment popular music based on rhythm. By computing a shortest path based on the self-similarity matrix calculated from a model of rhythm, segmenting boundaries are found along the di- agonal of the matrix. The cost of a new segment is opti- mized by matching manual...... and automatic segment boundaries. We compile a small song database of 21 randomly selected popular Chinese songs which come from Chinese Mainland, Taiwan and Hong Kong. The segmenting results on the small corpus show that 78% manual segmentation points are detected and 74% auto- matic segmentation points...

  11. Facial nerve activity disrupts psychomotor rhythms in the forehead microvasculature.

    Science.gov (United States)

    Drummond, Peter D; O'Brien, Geraldine

    2011-10-28

    Forehead blood flow was monitored in seven participants with a unilateral facial nerve lesion during relaxation, respiratory biofeedback and a sad documentary. Vascular waves at 0.1Hz strengthened during respiratory biofeedback, in tune with breathing cycles that also averaged 0.1Hz. In addition, a psychomotor rhythm at 0.15Hz was more prominent in vascular waveforms on the denervated than intact side of the forehead, both before and during relaxation and the sad documentary. These findings suggest that parasympathetic activity in the facial nerve interferes with the psychomotor rhythm in the forehead microvasculature. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. The Examination of Relationship between Life Rhythm and Parent's Consciousness among Young Children

    OpenAIRE

    Tanaka, Saori

    2008-01-01

    The social background of child care and rearing has changed rapidly today in Japan. Also young children's life rhythm has changed compared with before. These disorders of life rhythm cause big influence to young children's mind and body health. To improve young child's mind and body health, it is effective that parents improve the life rhythm at home. Therefore, the educational campaign to parents about young child's life rhythm was held. In this research, the relationship between improvement...

  13. The Rest-Activity Rhythm and Physical Activity in Early-Onset Dementia

    NARCIS (Netherlands)

    Hooghiemstra, A.M.; Eggermont, L.H.P.; Scheltens, P.; van der Flier, W.M.; Scherder, E.J.A.

    2015-01-01

    Background: A substantial part of elderly persons with dementia show rest-activity rhythm disturbances. The rest-activity rhythm is important to study in people with early-onset dementia (EOD) for rest-activity rhythm disturbances are predictive of institutionalization, and caregivers of young

  14. Children's Aural and Kinesthetic Understanding of Rhythm: Developing an Instructional Model

    Science.gov (United States)

    Foley, Adam D.

    2013-01-01

    The purpose of this study was to develop a deeper understanding of aural and kinesthetic rhythm skill development in elementary school-age children. In this study, I examined my curriculum model for rhythm understanding, which included creating and implementing assessments of movement skills in meter and rhythm. The research questions were: 1.…

  15. Relation between functional connectivity and rhythm discrimination in children who do and do not stutter

    Directory of Open Access Journals (Sweden)

    Soo-Eun Chang

    2016-01-01

    Full Text Available Our ability to perceive and produce rhythmic patterns in the environment supports fundamental human capacities ranging from music and language processing to the coordination of action. This article considers whether spontaneous correlated brain activity within a basal ganglia-thalamocortical (rhythm network is associated with individual differences in auditory rhythm discrimination. Moreover, do children who stutter with demonstrated deficits in rhythm perception have weaker links between rhythm network functional connectivity and rhythm discrimination? All children in the study underwent a resting-state fMRI session, from which functional connectivity measures within the rhythm network were extracted from spontaneous brain activity. In a separate session, the same children completed an auditory rhythm-discrimination task, where behavioral performance was assessed using signal detection analysis. We hypothesized that in typically developing children, rhythm network functional connectivity would be associated with behavioral performance on the rhythm discrimination task, but that this relationship would be attenuated in children who stutter. Results supported our hypotheses, lending strong support for the view that (1 children who stutter have weaker rhythm network connectivity and (2 the lack of a relation between rhythm network connectivity and rhythm discrimination in children who stutter may be an important contributing factor to the etiology of stuttering.

  16. Sleep, 24-hour activity rhythms, and brain structure : A population-based study

    NARCIS (Netherlands)

    L.A. Zuurbier (Lisette)

    2016-01-01

    markdownabstractIn this thesis, Chapter 2 focuses on sleep, 24-hour activity rhythms and health. Chapter 2.1 describes the influence of demographics, lifestyle and sleep on 24-hour activity rhythms. In Chapter 2.2 sleep and 24-hour activity rhythms are used to predict mortality. This chapter is

  17. Circadian Sleep-Wake Rhythm of Older Adults with Intellectual Disabilities

    Science.gov (United States)

    Maaskant, Marijke; van de Wouw, Ellen; van Wijck, Ruud; Evenhuis, Heleen M.; Echteld, Michael A.

    2013-01-01

    The circadian sleep-wake rhythm changes with aging, resulting in a more fragmented sleep-wake pattern. In individuals with intellectual disabilities (ID), brain structures regulating the sleep-wake rhythm might be affected. The aims of this study were to compare the sleep-wake rhythm of older adults with ID to that of older adults in the general…

  18. Exogenous melatonin entrains rhythm and reduces amplitude of endogenous melatonin : An in vivo microdialysis study

    NARCIS (Netherlands)

    Drijfhout, W.J; Homan, E.J; Brons, H.F; Oakley, M; Skingle, M; Grol, Cor; Westerink, B.H.C.

    The circadian rhythm of melatonin production was studied using on-line, in vivo microdialysis in the rat pineal gland. With this technique it was possible to record a pronounced melatonin rhythm with very high time resolution. Three phase-markers of the rhythm were calculated from the data,

  19. Perceiving Speech Rhythm in Music: Listeners Classify Instrumental Songs According to Language of Origin

    Science.gov (United States)

    Hannon, Eric E.

    2009-01-01

    Recent evidence suggests that the musical rhythm of a particular culture may parallel the speech rhythm of that culture's language (Patel, A. D., & Daniele, J. R. (2003). "An empirical comparison of rhythm in language and music." "Cognition, 87," B35-B45). The present experiments aimed to determine whether listeners actually perceive such rhythmic…

  20. Rhythm Perception and Its Role in Perception and Learning of Dysrhythmic Speech

    Science.gov (United States)

    Borrie, Stephanie A.; Lansford, Kaitlin L.; Barrett, Tyson S.

    2017-01-01

    Purpose: The perception of rhythm cues plays an important role in recognizing spoken language, especially in adverse listening conditions. Indeed, this has been shown to hold true even when the rhythm cues themselves are dysrhythmic. This study investigates whether expertise in rhythm perception provides a processing advantage for perception…

  1. Speech rhythm in Kannada speaking adults who stutter.

    Science.gov (United States)

    Maruthy, Santosh; Venugopal, Sahana; Parakh, Priyanka

    2017-10-01

    A longstanding hypothesis about the underlying mechanisms of stuttering suggests that speech disfluencies may be associated with problems in timing and temporal patterning of speech events. Fifteen adults who do and do not stutter read five sentences, and from these, the vocalic and consonantal durations were measured. Using these, pairwise variability index (raw PVI for consonantal intervals and normalised PVI for vocalic intervals) and interval based rhythm metrics (PercV, DeltaC, DeltaV, VarcoC and VarcoV) were calculated for all the participants. Findings suggested higher mean values in adults who stutter when compared to adults who do not stutter for all the rhythm metrics except for VarcoV. Further, statistically significant difference between the two groups was found for all the rhythm metrics except for VarcoV. Combining the present results with consistent prior findings based on rhythm deficits in children and adults who stutter, there appears to be strong empirical support for the hypothesis that individuals who stutter may have deficits in generation of rhythmic speech patterns.

  2. Activity rhythms and distribution of natal dens for red foxes

    Science.gov (United States)

    Wenyang, Zhou; Wanhong, Wei; Biggins, Dean E.

    1995-01-01

    The red fox, Vulpes vulpes, was investigated with snow tracking, radiotracking and directive observation at the Haibei Research Station of Alpine Meadow Ecosystem, Academia Sinica, from March to September 1994. The objectives of this study were to determine the distribution and use of natal dens, activity rhythms, and home range sizes for the foxes.

  3. The importance of hormonal circadian rhythms in daily feeding patterns

    NARCIS (Netherlands)

    Boumans, Iris J.M.M.; Boer, de Imke J.M.; Hofstede, Gert Jan; Fleur, la Susanne E.; Bokkers, Eddy

    2017-01-01

    The interaction between hormonal circadian rhythms and feeding behaviour is not well understood. This study aimed to deepen our understanding of mechanisms underlying circadian feeding behaviour in animals, using pigs, Sus scrofa, as a case study. Pigs show an alternans feeding pattern, that is,

  4. Rhythm Perturbations in Acoustically Paced Treadmill Walking After Stroke

    NARCIS (Netherlands)

    Roerdink, M.; Lamoth, C.J.C.; van Kordelaar, J.; Elich, P.; Konijnenbelt, M.; Kwakkel, G.; Beek, P.J.

    2009-01-01

    Background. In rehabilitation, acoustic rhythms are often used to improve gait after stroke. Acoustic cueing may enhance gait coordination by creating a stable coupling between heel strikes and metronome beats and provide a means to train the adaptability of gait coordination to environmental

  5. Circadian rhythms in the hypothalamo-pituitary-adrenal (HPA) axis

    NARCIS (Netherlands)

    Kalsbeek, A.; van der Spek, R.; Lei, J.; Endert, E.; Buijs, R. M.; Fliers, E.

    2012-01-01

    The pronounced daily variation in the release of adrenal hormones has been at the heart of the deciphering and understanding of the circadian timing system. Indeed, the first demonstration of an endocrine day/night rhythm was provided by Pincus (1943), by showing a daily pattern of 17-keto-steroid

  6. EEG alpha rhythm, ocular activity and basal skin resistance

    NARCIS (Netherlands)

    Verbaten, M.N.; Beaujon, J.N.R.; Sjouw, W.

    Most hypotheses about the origin of the occipital alpha rhythm stress the specific influence of ocular activity. In this study, the influence of eye-movement frequency and extreme upward deviation of the eyeballs (enlarging the corneo-retinal potential) on occipital alpha activity and basal skin

  7. Ultradian rhythm unmasked in the Pdf clock mutant of Drosophila

    Indian Academy of Sciences (India)

    2014-07-20

    Ohtomo et al. .... stand the influence of these two phases, short sampling segments were ... per-long (perL) mutants also showed ultradian rhythms un- der L:L ..... would like to dedicate this paper to the memory of Dr Obaid. Siddiqi.

  8. Mood Disorders, Circadian Rhythms, Melatonin and Melatonin Agonists

    Directory of Open Access Journals (Sweden)

    M.A. Quera Salva

    2012-04-01

    Full Text Available Recent advances in the understanding of circadian rhythms have led to an interest in the treatment of major depressive disorder with chronobiotic agents. Many tissues have autonomous circadian rhythms, which are orchestrated by the master clock, situated in the suprachiasmatic nucleus (SNC. Melatonin (N-acetyl-5-hydroxytryptamine is secreted from the pineal gland during darkness. Melatonin acts mainly on MT1 and MT2 receptors, which are present in the SNC, regulating physiological and neuroendocrine functions, including circadian entrainment, referred to as the chronobiotic effet. Circadian rhythms has been shown to be either misaligned or phase shifted or decreased in amplitude in both acute episodes and relapse of major depressive disorder (MDD and bipolar disorder. Manipulation of circadian rhythms either using physical treatments (such as high intensity light or behavioral therapy has shown promise in improving symptoms. Pharmacotherapy using melatonin and pure melatonin receptor agonists, while improving sleep, has not been shown to improve symptoms of depression. A novel antidepressant, agomelatine, combines 5HT2c antagonist and melatonin agonist action, and has shown promise in both acute treatment of MDD and in preventing relapse.

  9. Discrepancy between circadian rhythms of inulin and creatinine clearance

    NARCIS (Netherlands)

    van Acker, B. A.; Koomen, G. C.; Koopman, M. G.; Krediet, R. T.; Arisz, L.

    1992-01-01

    To elucidate the disparity between circadian rhythmicity of inulin and creatinine clearance, we simultaneously measured inulin and creatinine clearances every 3 hours during 1 day in 14 normal subjects and in 8 patients with nephrotic syndrome. All patients and normal subjects had a circadian rhythm

  10. An analysis of rhythm in Japanese and English popular music

    NARCIS (Netherlands)

    Sadakata, M.; Desain, P.W.M.; Honing, H.J.; Patel, A.D.; Iversen, J.R.

    2003-01-01

    Recently, there has been evidence that the rhythm in English and French non-vocal musical themes are significantly different in their contrastiveness of successive durations in the same manner as those of spoken language, suggesting that acomposer's native language exerts an influence on the music

  11. Rapping dyslexia : learning rhythm, rhyme and flow in dyslectic children

    NARCIS (Netherlands)

    Tittarelli, M.; Marti, P.; Peppoloni, D.

    2014-01-01

    The paper presents a design case that draws inspiration from rap music as a way to tell stories rhythmically, with simple instruments for accompaniment. Rhythm, rhymes and flow are key features of rap music. In this study, we attempted to apply rap principles and dynamics to a very specific field of

  12. Circadian rhythms, metabolism, and chrononutrition in rodents and humans

    Science.gov (United States)

    Chrononutrition is an emerging discipline that builds on the intimate relation between endogenous circadian (24-h) rhythms and metabolism. Circadian regulation of metabolic function can be observed from the level of intracellular biochemistry to whole-organism physiology and even postprandial respon...

  13. Studies on circadian rhythm disturbances and melatonin in delirium

    NARCIS (Netherlands)

    de Jonghe, A.-M.

    2014-01-01

    The circadian sleep/wake rhythm disturbances that are seen in delirium and the role of melatonin supplementation provide a new angle in delirium research. More research is needed to determine the role of melatonin in the pathophysiological mechanisms of delirium and to determine whether the

  14. Circadian Rhythm Shapes the Gut Microbiota Affecting Host Radiosensitivity.

    Science.gov (United States)

    Cui, Ming; Xiao, Huiwen; Luo, Dan; Zhang, Xin; Zhao, Shuyi; Zheng, Qisheng; Li, Yuan; Zhao, Yu; Dong, Jiali; Li, Hang; Wang, Haichao; Fan, Saijun

    2016-10-26

    Modern lifestyles, such as shift work, nocturnal social activities, and jet lag, disturb the circadian rhythm. The interaction between mammals and the co-evolved intestinal microbiota modulates host physiopathological processes. Radiotherapy is a cornerstone of modern management of malignancies; however, it was previously unknown whether circadian rhythm disorder impairs prognosis after radiotherapy. To investigate the effect of circadian rhythm on radiotherapy, C57BL/6 mice were housed in different dark/light cycles, and their intestinal bacterial compositions were compared using high throughput sequencing. The survival rate, body weight, and food intake of mice in diverse cohorts were measured following irradiation exposure. Finally, the enteric bacterial composition of irradiated mice that experienced different dark/light cycles was assessed using 16S RNA sequencing. Intriguingly, mice housed in aberrant light cycles harbored a reduction of observed intestinal bacterial species and shifts of gut bacterial composition compared with those of the mice kept under 12 h dark/12 h light cycles, resulting in a decrease of host radioresistance. Moreover, the alteration of enteric bacterial composition of mice in different groups was dissimilar. Our findings provide novel insights into the effects of biological clocks on the gut bacterial composition, and underpin that the circadian rhythm influences the prognosis of patients after radiotherapy in a preclinical setting.

  15. Transitions between beta and gamma rhythms in neural systems

    DEFF Research Database (Denmark)

    Sosnovtseva, Olga; Setsinsky, D; Fausbøll, Anders

    2002-01-01

    We study the coexistence of different rhythms in a local network of one inhibitory and two excitatory nerve cells for a wide range of the excitatory synapse strength and of the slow K+-channel conductance. The dynamic features of spike trains in the presence of noise are discussed. It is found...

  16. Capturing daily urban rhythms: the use of location aware technologies

    CSIR Research Space (South Africa)

    Krygsman, S

    2007-07-01

    Full Text Available Daily activities and travel often follow a natural rhythm or flow that is structured by the fixed spatial and temporal constraints. The work and home location act as pegs that define individual’s activity space and it is within these spaces...

  17. Rhythm perturbations in acoustically paced treadmill walking after stroke.

    Science.gov (United States)

    Roerdink, Melvyn; Lamoth, Claudine J C; van Kordelaar, Joost; Elich, Peter; Konijnenbelt, Manin; Kwakkel, Gert; Beek, Peter J

    2009-09-01

    In rehabilitation, acoustic rhythms are often used to improve gait after stroke. Acoustic cueing may enhance gait coordination by creating a stable coupling between heel strikes and metronome beats and provide a means to train the adaptability of gait coordination to environmental changes, as required in everyday life ambulation. To examine the stability and adaptability of auditory-motor synchronization in acoustically paced treadmill walking in stroke patients. Eleven stroke patients and 10 healthy controls walked on a treadmill at preferred speed and cadence under no metronome, single-metronome (pacing only paretic or nonparetic steps), and double-metronome (pacing both footfalls) conditions. The stability of auditory-motor synchronization was quantified by the variability of the phase relation between footfalls and beats. In a separate session, the acoustic rhythms were perturbed and adaptations to restore auditory-motor synchronization were quantified. For both groups, auditory-motor synchronization was more stable for double-metronome than single-metronome conditions, with stroke patients exhibiting an overall weaker coupling of footfalls to metronome beats than controls. The recovery characteristics following rhythm perturbations corroborated the stability findings and further revealed that stroke patients had difficulty in accelerating their steps and instead preferred a slower-step response to restore synchronization. In gait rehabilitation practice, the use of acoustic rhythms may be more effective when both footfalls are paced. In addition, rhythm perturbations during acoustically paced treadmill walking may not only be employed to evaluate the stability of auditory-motor synchronization but also have promising implications for evaluation and training of gait adaptations in neurorehabilitation practice.

  18. [Circadian rhythm : Influence on Epworth Sleepiness Scale score].

    Science.gov (United States)

    Herzog, M; Bedorf, A; Rohrmeier, C; Kühnel, T; Herzog, B; Bremert, T; Plontke, S; Plößl, S

    2017-02-01

    The Epworth Sleepiness Scale (ESS) is frequently used to determine daytime sleepiness in patients with sleep-disordered breathing. It is still unclear whether different levels of alertness induced by the circadian rhythm influence ESS score. The aim of this study is to investigate the influence of circadian rhythm-dependent alertness on ESS performance. In a monocentric prospective noninterventional observation study, 97 patients with suspected sleep-disordered breathing were investigated with respect to daytime sleepiness in temporal relationship to polysomnographic examination and treatment. The Karolinska Sleepiness Scale (KSS) and the Stanford Sleepiness Scale (SSS) served as references for the detection of present sleepiness at three different measurement times (morning, noon, evening), prior to and following a diagnostic polysomnography night as well as after a continuous positive airway pressure (CPAP) titration night (9 measurements in total). The KSS, SSS, and ESS were performed at these times in a randomized order. The KSS and SSS scores revealed a circadian rhythm-dependent curve with increased sleepiness at noon and in the evening. Following a diagnostic polysomnography night, the scores were increased compared to the measurements prior to the night. After the CPAP titration night, sleepiness in the morning was reduced. KSS and SSS reflect the changes in alertness induced by the circadian rhythm. The ESS score war neither altered by the intra-daily nor by the inter-daily changes in the level of alertness. According to the present data, the ESS serves as a reliable instrument to detect the level of daytime sleepiness independently of the circadian rhythm-dependent level of alertness.

  19. Rhythm and timing in autism: Learning to dance

    Directory of Open Access Journals (Sweden)

    Pat eAmos

    2013-04-01

    Full Text Available In recent years, a significant body of research has focused on challenges to neural connectivity as a key to understanding autism. In contrast to attempts to identify a single static, primarily brain-based deficit, children and adults diagnosed with autism are increasingly perceived as out of sync with their internal and external environments in dynamic ways that must also involve operations of the peripheral nervous systems. The noisiness that seems to occur in both directions of neural flow may help explain challenges to movement and sensing, and ultimately to entrainment with circadian rhythms and social interactions. across the autism spectrum. Profound differences in the rhythm and timing of movement have been tracked to infancy. Difficulties with self-synchrony inhibit praxis, and can disrupt the dance of relationships through which caregiver and child build meaning. Different sensory aspects of a situation may fail to match up; ultimately, intentions and actions themselves may be uncoupled. This uncoupling may help explain the expressions of alienation from the actions of one’s body which recur in the autobiographical autism literature. Multi-modal/cross-modal coordination of different types of sensory information into coherent events may be difficult to achieve because amodal properties (e.g. rhythm and tempo that help unite perceptions are unreliable. One question posed to the connectivity research concerns the role of rhythm and timing in this operation, and whether these can be mobilized to reduce overload and enhance performance. A case is made for developmental research addressing how people with autism actively explore and make sense of their environments. The parent/author recommends investigating approaches such as scaffolding interactions via rhythm, following the person’s lead, slowing the pace, discriminating between intentional communication and stray motor patterns, and organizing information through one sensory mode at

  20. Got Rhythm...For Better and for Worse. Cross-Modal Effects of Auditory Rhythm on Visual Word Recognition

    Science.gov (United States)

    Brochard, Renaud; Tassin, Maxime; Zagar, Daniel

    2013-01-01

    The present research aimed to investigate whether, as previously observed with pictures, background auditory rhythm would also influence visual word recognition. In a lexical decision task, participants were presented with bisyllabic visual words, segmented into two successive groups of letters, while an irrelevant strongly metric auditory…

  1. The role of feeding rhythm, adrenal hormones and neuronal inputs in synchronizing daily clock gene rhythms in the liver

    NARCIS (Netherlands)

    Su, Yan; Cailotto, Cathy; Foppen, Ewout; Jansen, Remi; Zhang, Zhi; Buijs, Ruud; Fliers, Eric; Kalsbeek, Andries

    2016-01-01

    The master clock in the hypothalamic suprachiasmatic nucleus (SCN) is assumed to distribute rhythmic information to the periphery via neural, humoral and/or behavioral connections. Until now, feeding, corticosterone and neural inputs are considered important signals for synchronizing daily rhythms

  2. Mother-infant circadian rhythm: development of individual patterns and dyadic synchrony.

    Science.gov (United States)

    Thomas, Karen A; Burr, Robert L; Spieker, Susan; Lee, Jungeun; Chen, Jessica

    2014-12-01

    Mutual circadian rhythm is an early and essential component in the development of maternal-infant physiological synchrony. The aim of this to examine the longitudinal pattern of maternal-infant circadian rhythm and rhythm synchrony as measured by rhythm parameters. In-home dyadic actigraphy monitoring at infant age 4, 8, and 12 weeks. Forty-three healthy mother-infant pairs. Circadian parameters derived from cosinor and non-parametric analysis including mesor, magnitude, acrophase, L5 and M10 midpoints (midpoint of lowest 5 and highest 10h of activity), amplitude, interdaily stability (IS), and intradaily variability (IV). Mothers experienced early disruption of circadian rhythm, with re-establishment of rhythm over time. Significant time effects were noted in increasing maternal magnitude, amplitude, and IS and decreasing IV (pcircadian pattern with significant time effects for increasing mesor, magnitude, amplitude, L5, IS, and IV (pcircadian rhythm. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  3. Alternative Mating Tactics in Male Chameleons (Chamaeleo chamaeleon) Are Evident in Both Long-Term Body Color and Short-Term Courtship Pattern

    Science.gov (United States)

    Keren-Rotem, Tammy; Levy, Noga; Wolf, Lior; Bouskila, Amos; Geffen, Eli

    2016-01-01

    Alternative mating tactics in males of various taxa are associated with body color, body size, and social status. Chameleons are known for their ability to change body color following immediate environmental or social stimuli. In this study, we examined whether the differential appearance of male common chameleon during the breeding season is indeed an expression of alternative mating tactics. We documented body color of males and used computer vision techniques to classify images of individuals into discrete color patterns associated with seasons, individual characteristics, and social contexts. Our findings revealed no differences in body color and color patterns among males during the non-breeding season. However, during the breeding season males appeared in several color displays, which reflected body size, social status, and behavioral patterns. Furthermore, smaller and younger males resembled the appearance of small females. Consequently, we suggest that long-term color change in males during the breeding season reflects male alternative mating tactics. Upon encounter with a receptive female, males rapidly alter their appearance to that of a specific brief courtship display, which reflects their social status. The females, however, copulated indiscriminately in respect to male color patterns. Thus, we suggest that the differential color patterns displayed by males during the breeding season are largely aimed at inter-male signaling. PMID:27409771

  4. Alternative Mating Tactics in Male Chameleons (Chamaeleo chamaeleon Are Evident in Both Long-Term Body Color and Short-Term Courtship Pattern.

    Directory of Open Access Journals (Sweden)

    Tammy Keren-Rotem

    Full Text Available Alternative mating tactics in males of various taxa are associated with body color, body size, and social status. Chameleons are known for their ability to change body color following immediate environmental or social stimuli. In this study, we examined whether the differential appearance of male common chameleon during the breeding season is indeed an expression of alternative mating tactics. We documented body color of males and used computer vision techniques to classify images of individuals into discrete color patterns associated with seasons, individual characteristics, and social contexts. Our findings revealed no differences in body color and color patterns among males during the non-breeding season. However, during the breeding season males appeared in several color displays, which reflected body size, social status, and behavioral patterns. Furthermore, smaller and younger males resembled the appearance of small females. Consequently, we suggest that long-term color change in males during the breeding season reflects male alternative mating tactics. Upon encounter with a receptive female, males rapidly alter their appearance to that of a specific brief courtship display, which reflects their social status. The females, however, copulated indiscriminately in respect to male color patterns. Thus, we suggest that the differential color patterns displayed by males during the breeding season are largely aimed at inter-male signaling.

  5. Musical genres: beating to the rhythms of different drums

    Energy Technology Data Exchange (ETDEWEB)

    Correa, Debora C; Costa, Luciano da F [Instituto de Fisica de Sao Carlos - Universidade de Sao Paulo, Av. Trabalhador Sao Carlense 400, Caixa Postal 369, CEP 13560-970, Sao Carlos, Sao Paulo (Brazil); Saito, Jose H, E-mail: deboracorrea@ursa.ifsc.usp.b, E-mail: luciano@ursa.ifsc.usp.b [Departamento de Computacao-Universidade Federal de Sao Carlos, Rodovia Washington Luis, km 235, SP-310, CEP 13565-905, Sao Carlos, Sao Paulo (Brazil)

    2010-05-15

    Online music databases have increased significantly as a consequence of the rapid growth of the Internet and digital audio, requiring the development of faster and more efficient tools for music content analysis. Musical genres are widely used to organize music collections. In this paper, the problem of automatic single and multi-label music genre classification is addressed by exploring rhythm-based features obtained from a respective complex network representation. A Markov model is built in order to analyse the temporal sequence of rhythmic notation events. Feature analysis is performed by using two multivariate statistical approaches: principal components analysis (unsupervised) and linear discriminant analysis (supervised). Similarly, two classifiers are applied in order to identify the category of rhythms: parametric Bayesian classifier under the Gaussian hypothesis (supervised) and agglomerative hierarchical clustering (unsupervised). Qualitative results obtained by using the kappa coefficient and the obtained clusters corroborated the effectiveness of the proposed method.

  6. Musical genres: beating to the rhythms of different drums

    Science.gov (United States)

    Correa, Debora C.; Saito, Jose H.; Costa, Luciano da F.

    2010-05-01

    Online music databases have increased significantly as a consequence of the rapid growth of the Internet and digital audio, requiring the development of faster and more efficient tools for music content analysis. Musical genres are widely used to organize music collections. In this paper, the problem of automatic single and multi-label music genre classification is addressed by exploring rhythm-based features obtained from a respective complex network representation. A Markov model is built in order to analyse the temporal sequence of rhythmic notation events. Feature analysis is performed by using two multivariate statistical approaches: principal components analysis (unsupervised) and linear discriminant analysis (supervised). Similarly, two classifiers are applied in order to identify the category of rhythms: parametric Bayesian classifier under the Gaussian hypothesis (supervised) and agglomerative hierarchical clustering (unsupervised). Qualitative results obtained by using the kappa coefficient and the obtained clusters corroborated the effectiveness of the proposed method.

  7. Photoperiodic regulation of the hamster testis: dependence on circadian rhythms

    International Nuclear Information System (INIS)

    Eskes, G.A.; Zucker, I.

    1978-01-01

    The testes of hamsters exposed to short days (10 hr of light per day) regress within 13 weeks. Administration of 7.5 percent deuterium oxide to hamsters lengthens the period of free running circadian activity rhythms by 2.2 percent and prevents testicular regression during short-day exposure. This is consistent with predictions derived from an external coincidence model for photoperiodic time measurement: Deuterium oxide changes phase relationships between the light-dark cycle and the circadian system, the hamster's daily photosensitive phase is stimulated with light during short days, and the testes remain large. Conservation of the period of circadian rhythms within narrow limits has adaptive significance for hamster photoperiodism and for the occurrence and phasing of the annual reproductive cycle

  8. Hericium erinaceus extracts alter behavioral rhythm in mice.

    Science.gov (United States)

    Furuta, Shoko; Kuwahara, Rika; Hiraki, Eri; Ohnuki, Koichiro; Yasuo, Shinobu; Shimizu, Kuniyoshi

    2016-01-01

    Hericium erinaceus (HE), an edible mushroom, has been used as a herbal medicine in several Asian countries since ancient times. HE has potential as a medicine for the treatment and prevention of dementia, a disorder closely linked with circadian rhythm. This study investigated the effects of the intake of HE extracts on behavioral rhythm, photosensitivity of the circadian clock, and clock gene mRNA expression in the suprachiasmatic nucleus (SCN), a central clock, in mice. Although the HE ethanol extract only affected the offset time of activity, the HE water extract advanced the sleep-wake cycle without affecting the free-running period, photosensitivity, or the clock gene mRNA expression in SCN. In addition, both extracts decreased wakefulness around end of active phase. The findings of the present study suggest that HE may serve as a functional food in the prevention and treatment of Alzheimer's disease and delayed sleep phase syndrome.

  9. Musical genres: beating to the rhythms of different drums

    International Nuclear Information System (INIS)

    Correa, Debora C; Costa, Luciano da F; Saito, Jose H

    2010-01-01

    Online music databases have increased significantly as a consequence of the rapid growth of the Internet and digital audio, requiring the development of faster and more efficient tools for music content analysis. Musical genres are widely used to organize music collections. In this paper, the problem of automatic single and multi-label music genre classification is addressed by exploring rhythm-based features obtained from a respective complex network representation. A Markov model is built in order to analyse the temporal sequence of rhythmic notation events. Feature analysis is performed by using two multivariate statistical approaches: principal components analysis (unsupervised) and linear discriminant analysis (supervised). Similarly, two classifiers are applied in order to identify the category of rhythms: parametric Bayesian classifier under the Gaussian hypothesis (supervised) and agglomerative hierarchical clustering (unsupervised). Qualitative results obtained by using the kappa coefficient and the obtained clusters corroborated the effectiveness of the proposed method.

  10. Stable isotope ratios in hair and teeth reflect biologic rhythms.

    Directory of Open Access Journals (Sweden)

    Otto Appenzeller

    Full Text Available Biologic rhythms give insight into normal physiology and disease. They can be used as biomarkers for neuronal degenerations. We present a diverse data set to show that hair and teeth contain an extended record of biologic rhythms, and that analysis of these tissues could yield signals of neurodegenerations. We examined hair from mummified humans from South America, extinct mammals and modern animals and people, both healthy and diseased, and teeth of hominins. We also monitored heart-rate variability, a measure of a biologic rhythm, in some living subjects and analyzed it using power spectra. The samples were examined to determine variations in stable isotope ratios along the length of the hair and across growth-lines of the enamel in teeth. We found recurring circa-annual periods of slow and fast rhythms in hydrogen isotope ratios in hair and carbon and oxygen isotope ratios in teeth. The power spectra contained slow and fast frequency power, matching, in terms of normalized frequency, the spectra of heart rate variability found in our living subjects. Analysis of the power spectra of hydrogen isotope ratios in hair from a patient with neurodegeneration revealed the same spectral features seen in the patient's heart-rate variability. Our study shows that spectral analysis of stable isotope ratios in readily available tissues such as hair could become a powerful diagnostic tool when effective treatments and neuroprotective drugs for neurodegenerative diseases become available. It also suggests that similar analyses of archaeological specimens could give insight into the physiology of ancient people and animals.

  11. Transitions between beta and gamma rhythms in neural systems

    DEFF Research Database (Denmark)

    Sosnovtseva, Olga; Setsinsky, D.; Fausbøll, Anders

    2002-01-01

    We study the coexistence of different rhythms in a local network of one inhibitory and two excitatory nerve cells for a wide range of the excitatory synapse strength and of the slow K+-channel conductance. The dynamic features of spike trains in the presence of noise are discussed. It is found...... that noise can both cause switching between different states and induce coherent firing events....

  12. Air Travel, Circadian Rhythms/Hormones, and Autoimmunity.

    Science.gov (United States)

    Torres-Ruiz, J; Sulli, A; Cutolo, M; Shoenfeld, Y

    2017-08-01

    Biological rhythms are fundamental for homeostasis and have recently been involved in the regulatory processes of various organs and systems. Circadian cycle proteins and hormones have a direct effect on the inflammatory response and have shown pro- or anti-inflammatory effects in animal models of autoimmune diseases. The cells of the immune system have their own circadian rhythm, and the light-dark cycle directly influences the inflammatory response. On the other hand, patients with autoimmune diseases characteristically have sleep disorders and fatigue, and in certain disease, such as rheumatoid arthritis (RA), a frank periodicity in the signs and symptoms is recognized. The joint symptoms predominate in the morning, and apparently, subjects with RA have relative adrenal insufficiency, with a cortisol peak unable to control the late night load of pro-inflammatory cytokines. Transatlantic flights represent a challenge in the adjustment of biological rhythms, since they imply sleep deprivation, time zone changes, and potential difficulties for drug administration. In patients with autoimmune diseases, the use of DMARDs and prednisone at night is probably best suited to lessen morning symptoms. It is also essential to sleep during the trip to improve adaptation to the new time zone and to avoid, as far as possible, works involving flexible or nocturnal shifts. The study of proteins and hormones related to biological rhythms will demonstrate new pathophysiological pathways of autoimmune diseases, which will emphasize the use of general measures for sleep respect and methods for drug administration at key daily times to optimize their anti-inflammatory and immune modulatory effects.

  13. Chorusing, synchrony and the evolutionary functions of rhythm

    Directory of Open Access Journals (Sweden)

    Andrea eRavignani

    2014-10-01

    Full Text Available A central goal of biomusicology is to understand the biological basis of human musicality. One approach to this problem has been to compare core components of human musicality (relative pitch perception, entrainment, etc. with similar capacities in other animal species. Here we extend and clarify this comparative approach with respect to rhythm. First, whereas most comparisons between human music and animal acoustic behavior have focused on spectral properties (melody and harmony, we argue for the central importance of temporal properties, and propose that this domain is ripe for further comparative research. Second, whereas most rhythm research in non-human animals has examined animal timing in isolation, we consider how chorusing dynamics can shape individual timing, as in human music and dance, making group behavior key to understand the adaptive functions of rhythm. To illustrate the interdependence between individual and chorusing dynamics, we present a computational model of chorusing agents relating individual call timing with synchronous group behavior. Third, we distinguish and clarify mechanistic and functional explanations of rhythmic phenomena, often conflated in the literature, arguing that this distinction is key for understanding the evolution of musicality. Fourth, we expand biomusicological discussions beyond the species typically considered, providing an overview of chorusing and rhythmic behavior across a broad range of taxa (orthopterans, fireflies, frogs, birds, and primates. Finally, we propose an Evolving Signal Timing hypothesis, suggesting that similarities between timing abilities in biological species will be based on comparable chorusing behaviors. We conclude that the comparative study of chorusing species can provide important insights into the adaptive function(s of rhythmic behavior in our proto-musical primate ancestors, and thus inform our understanding of the biology and evolution of rhythm in human music and

  14. Chorusing, synchrony, and the evolutionary functions of rhythm.

    Science.gov (United States)

    Ravignani, Andrea; Bowling, Daniel L; Fitch, W Tecumseh

    2014-01-01

    A central goal of biomusicology is to understand the biological basis of human musicality. One approach to this problem has been to compare core components of human musicality (relative pitch perception, entrainment, etc.) with similar capacities in other animal species. Here we extend and clarify this comparative approach with respect to rhythm. First, whereas most comparisons between human music and animal acoustic behavior have focused on spectral properties (melody and harmony), we argue for the central importance of temporal properties, and propose that this domain is ripe for further comparative research. Second, whereas most rhythm research in non-human animals has examined animal timing in isolation, we consider how chorusing dynamics can shape individual timing, as in human music and dance, arguing that group behavior is key to understanding the adaptive functions of rhythm. To illustrate the interdependence between individual and chorusing dynamics, we present a computational model of chorusing agents relating individual call timing with synchronous group behavior. Third, we distinguish and clarify mechanistic and functional explanations of rhythmic phenomena, often conflated in the literature, arguing that this distinction is key for understanding the evolution of musicality. Fourth, we expand biomusicological discussions beyond the species typically considered, providing an overview of chorusing and rhythmic behavior across a broad range of taxa (orthopterans, fireflies, frogs, birds, and primates). Finally, we propose an "Evolving Signal Timing" hypothesis, suggesting that similarities between timing abilities in biological species will be based on comparable chorusing behaviors. We conclude that the comparative study of chorusing species can provide important insights into the adaptive function(s) of rhythmic behavior in our "proto-musical" primate ancestors, and thus inform our understanding of the biology and evolution of rhythm in human music and

  15. Dynamic correlations between heart and brain rhythm during Autogenic meditation

    OpenAIRE

    Kim, Dae-Keun; Lee, Kyung-Mi; Kim, Jongwha; Whang, Min-Cheol; Kang, Seung Wan

    2013-01-01

    This study is aimed to determine significant physiological parameters of brain and heart under meditative state, both in each activities and their dynamic correlations. Electrophysiological changes in response to meditation were explored in 12 healthy volunteers who completed 8 weeks of a basic training course in autogenic meditation. Heart coherence, representing the degree of ordering in oscillation of heart rhythm intervals, increased significantly during meditation. Relative EEG alpha pow...

  16. Circadian activity rhythms for mothers with an infant in ICU

    Directory of Open Access Journals (Sweden)

    Shih-Yu eLee

    2010-12-01

    Full Text Available Circadian rhythms influence sleep and wakefulness. Circadian activity rhythms (CAR are altered in individuals with dementia or seasonal affective disorder. To date, studies exploring CAR and sleep in postpartum women are rare. The purpose of this report is to describe relationships between CAR, sleep disturbance, and fatigue among 72 first-time mothers during their 2nd week postpartum while their newborn remain hospitalized in intensive care unit (ICU. Seventy two mothers were included in this secondary data analysis sample from three separate studies. Participants completed the General Sleep Disturbance Scale (GSDS, Numerical Rating Scale for Fatigue (NRS-F, and a sleep diary. The objective sleep data included total sleep time (TST, wake after sleep onset (WASO, and CAR determined by the circadian quotient (amplitude/mesor averaged from at least 48-hours of wrist actigraphy monitoring. The TST of mothers who self-reported as poor sleepers was 354 minutes (SEM= 21.9, with a mean WASO of 19.5% (SEM= 2.8. The overall sleep quality measured by the GSDS was clinically, significantly disrupted (M= 5.5, SD= 1.2. The mean score for morning fatigue was 5.8 (SD= 2.0, indicating moderate fatigue severity. The CAR was .62 (SEM= .04, indicating poor synchronization. The self-reported good sleepers (GSDS < 3 had better CAR (M= .71, SEM= .02 than poor sleepers (GSDS > 3 (t [70] = 2.0, p< .05. A higher circadian equation was associated with higher TST (r= .83, p<.001, less WASO (r= -.50, p< .001, lower self-reported sleep disturbance scores (r= -.35, p= .01, and less morning fatigue (r= -.26. Findings indicate that mothers with a hospitalized infant have both nocturnal sleep problems and disturbed circadian activity rhythms. Factors responsible for these sleep and rhythm disturbances, the adverse effects on mother’s physical and mental well-being, and mother-infant relationship require further study.

  17. Multiple Scale Music Segmentation Using Rhythm, Timbre, and Harmony

    Directory of Open Access Journals (Sweden)

    Kristoffer Jensen

    2007-01-01

    Full Text Available The segmentation of music into intro-chorus-verse-outro, and similar segments, is a difficult topic. A method for performing automatic segmentation based on features related to rhythm, timbre, and harmony is presented, and compared, between the features and between the features and manual segmentation of a database of 48 songs. Standard information retrieval performance measures are used in the comparison, and it is shown that the timbre-related feature performs best.

  18. The emerging importance of ultradian glucocorticoid rhythms within metabolic pathology.

    Science.gov (United States)

    Flynn, Benjamin P; Conway-Campbell, Becky L; Lightman, Stafford L

    2018-06-01

    Glucocorticoid (GC) hormones play significant roles within homeostasis and the chrono-dynamics of their regulatory role has become increasingly recognised within dysregulated GC pathology, particularly with metabolic phenotypes. Within this article, we will discuss the relevance of the ultradian homeostatic rhythm, how its dysregulation effects glucocorticoid receptor and RNA polymeraseII recruitment and may play a significant role within aberrant metabolic action. Copyright © 2018 The Authors. Published by Elsevier Masson SAS.. All rights reserved.

  19. Portable wireless neurofeedback system of EEG alpha rhythm enhances memory.

    Science.gov (United States)

    Wei, Ting-Ying; Chang, Da-Wei; Liu, You-De; Liu, Chen-Wei; Young, Chung-Ping; Liang, Sheng-Fu; Shaw, Fu-Zen

    2017-11-13

    Effect of neurofeedback training (NFT) on enhancement of cognitive function or amelioration of clinical symptoms is inconclusive. The trainability of brain rhythm using a neurofeedback system is uncertainty because various experimental designs are used in previous studies. The current study aimed to develop a portable wireless NFT system for alpha rhythm and to validate effect of the NFT system on memory with a sham-controlled group. The proposed system contained an EEG signal analysis device and a smartphone with wireless Bluetooth low-energy technology. Instantaneous 1-s EEG power and contiguous 5-min EEG power throughout the training were developed as feedback information. The training performance and its progression were kept to boost usability of our device. Participants were blinded and randomly assigned into either the control group receiving random 4-Hz power or Alpha group receiving 8-12-Hz power. Working memory and episodic memory were assessed by the backward digital span task and word-pair task, respectively. The portable neurofeedback system had advantages of a tiny size and long-term recording and demonstrated trainability of alpha rhythm in terms of significant increase of power and duration of 8-12 Hz. Moreover, accuracies of the backward digital span task and word-pair task showed significant enhancement in the Alpha group after training compared to the control group. Our tiny portable device demonstrated success trainability of alpha rhythm and enhanced two kinds of memories. The present study suggest that the portable neurofeedback system provides an alternative intervention for memory enhancement.

  20. Light and Cognition: Roles for Circadian Rhythms, Sleep, and Arousal

    Science.gov (United States)

    Fisk, Angus S.; Tam, Shu K. E.; Brown, Laurence A.; Vyazovskiy, Vladyslav V.; Bannerman, David M.; Peirson, Stuart N.

    2018-01-01

    Light exerts a wide range of effects on mammalian physiology and behavior. As well as synchronizing circadian rhythms to the external environment, light has been shown to modulate autonomic and neuroendocrine responses as well as regulating sleep and influencing cognitive processes such as attention, arousal, and performance. The last two decades have seen major advances in our understanding of the retinal photoreceptors that mediate these non-image forming responses to light, as well as the neural pathways and molecular mechanisms by which circadian rhythms are generated and entrained to the external light/dark (LD) cycle. By contrast, our understanding of the mechanisms by which lighting influences cognitive processes is more equivocal. The effects of light on different cognitive processes are complex. As well as the direct effects of light on alertness, indirect effects may also occur due to disrupted circadian entrainment. Despite the widespread use of disrupted LD cycles to study the role circadian rhythms on cognition, the different experimental protocols used have subtly different effects on circadian function which are not always comparable. Moreover, these protocols will also disrupt sleep and alter physiological arousal, both of which are known to modulate cognition. Studies have used different assays that are dependent on different cognitive and sensory processes, which may also contribute to their variable findings. Here, we propose that studies addressing the effects of different lighting conditions on cognitive processes must also account for their effects on circadian rhythms, sleep, and arousal if we are to fully understand the physiological basis of these responses. PMID:29479335

  1. Visible light alters yeast metabolic rhythms by inhibiting respiration

    OpenAIRE

    Robertson, James Brian; Davis, Chris R.; Johnson, Carl Hirschie

    2013-01-01

    In some organisms, respiration fluctuates cyclically, and these rhythms can be a sensitive gauge of metabolism. Constant or pulsatile exposure of yeast to visible wavelengths of light significantly alters and/or initiates these respiratory oscillations, revealing a further dimension of the challenges to yeast living in natural environments. Our results also have implications for the use of light as research tools—e.g., for excitation of fluorescence microscopically—even in organisms such as y...

  2. CIRCADIAN RHYTHMS FROM MULTIPLE OSCILLATORS: LESSONS FROM DIVERSE ORGANISMS

    OpenAIRE

    Bell-Pedersen, Deborah; Cassone, Vincent M.; Earnest, David J.; Golden, Susan S.; Hardin, Paul E.; Thomas, Terry L.; Zoran, Mark J.

    2005-01-01

    The organization of biological activities into daily cycles is universal in organisms as diverse as cyanobacteria, fungi, algae, plants, flies, birds and man. Comparisons of circadian clocks in unicellular and multicellular organisms using molecular genetics and genomics have provided new insights into the mechanisms and complexity of clock systems. Whereas unicellular organisms require stand-alone clocks that can generate 24-hour rhythms for diverse processes, organisms with differentiated t...

  3. Action experience, more than observation, influences mu rhythm desynchronization.

    Directory of Open Access Journals (Sweden)

    Erin N Cannon

    Full Text Available Since the discovery of mirror neurons in premotor and parietal areas of the macaque monkey, the idea that action and perception may share the same neural code has been of central interest in social, developmental, and cognitive neurosciences. A fundamental question concerns how a putative human mirror neuron system may be tuned to the motor experiences of the individual. The current study tested the hypothesis that prior motor experience modulated the sensorimotor mu and beta rhythms. Specifically, we hypothesized that these sensorimotor rhythms would be more desynchronized after active motor experience compared to passive observation experience. To test our hypothesis, we collected EEG from adult participants during the observation of a relatively novel action: an experimenter used a claw-like tool to pick up a toy. Prior to EEG collection, we trained one group of adults to perform this action with the tool (performers. A second group comprised trained video coders, who only had experience observing the action (observers. Both the performers and the observers had no prior motor and visual experience with the action. A third group of novices was also tested. Performers exhibited the greatest mu rhythm desynchronization in the 8-13 Hz band, particularly in the right hemisphere compared to observers and novices. This study is the first to contrast active tool-use experience and observation experience in the mu rhythm and to show modulation with relatively shorter amounts of experience than prior mirror neuron expertise studies. These findings are discussed with respect to its broader implication as a neural signature for a mechanism of early social learning.

  4. A multimodal spectral approach to characterize rhythm in natural speech.

    Science.gov (United States)

    Alexandrou, Anna Maria; Saarinen, Timo; Kujala, Jan; Salmelin, Riitta

    2016-01-01

    Human utterances demonstrate temporal patterning, also referred to as rhythm. While simple oromotor behaviors (e.g., chewing) feature a salient periodical structure, conversational speech displays a time-varying quasi-rhythmic pattern. Quantification of periodicity in speech is challenging. Unimodal spectral approaches have highlighted rhythmic aspects of speech. However, speech is a complex multimodal phenomenon that arises from the interplay of articulatory, respiratory, and vocal systems. The present study addressed the question of whether a multimodal spectral approach, in the form of coherence analysis between electromyographic (EMG) and acoustic signals, would allow one to characterize rhythm in natural speech more efficiently than a unimodal analysis. The main experimental task consisted of speech production at three speaking rates; a simple oromotor task served as control. The EMG-acoustic coherence emerged as a sensitive means of tracking speech rhythm, whereas spectral analysis of either EMG or acoustic amplitude envelope alone was less informative. Coherence metrics seem to distinguish and highlight rhythmic structure in natural speech.

  5. Sleep, circadian rhythm and body weight: parallel developments.

    Science.gov (United States)

    Westerterp-Plantenga, Margriet S

    2016-11-01

    Circadian alignment is crucial for body-weight management, and for metabolic health. In this context, circadian alignment consists of alignment of sleep, meal patterns and physical activity. During puberty a significant reduction in sleep duration occurs, and pubertal status is inversely associated with sleep duration. A consistent inverse association between habitual sleep duration and body-weight development occurs, independent of possible confounders. Research on misalignment reveals that circadian misalignment affects sleep-architecture and subsequently disturbs glucose-insulin metabolism, substrate oxidation, leptin- and ghrelin concentrations, appetite, food reward, hypothalamic-pituitary-adrenal-axis activity and gut-peptide concentrations enhancing positive energy balance and metabolic disturbance. Not only aligning meals and sleep in a circadian way is crucial, also regular physical activity during the day strongly promotes the stability and amplitude of circadian rhythm, and thus may serve as an instrument to restore poor circadian rhythms. Endogenicity may play a role in interaction of these environmental variables with a genetic predisposition. In conclusion, notwithstanding the separate favourable effects of sufficient daily physical activity, regular meal patterns, sufficient sleep duration and quality sleep on energy balance, the overall effect of the amplitude and stability of the circadian rhythm, perhaps including genetic predisposition, may integrate the separate effects in an additive way.

  6. Visual Timing of Structured Dance Movements Resembles Auditory Rhythm Perception

    Science.gov (United States)

    Su, Yi-Huang; Salazar-López, Elvira

    2016-01-01

    Temporal mechanisms for processing auditory musical rhythms are well established, in which a perceived beat is beneficial for timing purposes. It is yet unknown whether such beat-based timing would also underlie visual perception of temporally structured, ecological stimuli connected to music: dance. In this study, we investigated whether observers extracted a visual beat when watching dance movements to assist visual timing of these movements. Participants watched silent videos of dance sequences and reproduced the movement duration by mental recall. We found better visual timing for limb movements with regular patterns in the trajectories than without, similar to the beat advantage for auditory rhythms. When movements involved both the arms and the legs, the benefit of a visual beat relied only on the latter. The beat-based advantage persisted despite auditory interferences that were temporally incongruent with the visual beat, arguing for the visual nature of these mechanisms. Our results suggest that visual timing principles for dance parallel their auditory counterparts for music, which may be based on common sensorimotor coupling. These processes likely yield multimodal rhythm representations in the scenario of music and dance. PMID:27313900

  7. Dynamic markers of altered gait rhythm in amyotrophic lateral sclerosis

    Science.gov (United States)

    Hausdorff, J. M.; Lertratanakul, A.; Cudkowicz, M. E.; Peterson, A. L.; Kaliton, D.; Goldberger, A. L.

    2000-01-01

    Amyotrophic lateral sclerosis (ALS) is a disorder marked by loss of motoneurons. We hypothesized that subjects with ALS would have an altered gait rhythm, with an increase in both the magnitude of the stride-to-stride fluctuations and perturbations in the fluctuation dynamics. To test for this locomotor instability, we quantitatively compared the gait rhythm of subjects with ALS with that of normal controls and with that of subjects with Parkinson's disease (PD) and Huntington's disease (HD), pathologies of the basal ganglia. Subjects walked for 5 min at their usual pace wearing an ankle-worn recorder that enabled determination of the duration of each stride and of stride-to-stride fluctuations. We found that the gait of patients with ALS is less steady and more temporally disorganized compared with that of healthy controls. In addition, advanced ALS, HD, and PD were associated with certain common, as well as apparently distinct, features of altered stride dynamics. Thus stride-to-stride control of gait rhythm is apparently compromised with ALS. Moreover, a matrix of markers based on gait dynamics may be useful in characterizing certain pathologies of motor control and, possibly, in quantitatively monitoring disease progression and evaluating therapeutic interventions.

  8. Dual Gamma Rhythm Generators Control Interlaminar Synchrony in Auditory Cortex

    Science.gov (United States)

    Ainsworth, Matthew; Lee, Shane; Cunningham, Mark O.; Roopun, Anita K.; Traub, Roger D.; Kopell, Nancy J.; Whittington, Miles A.

    2013-01-01

    Rhythmic activity in populations of cortical neurons accompanies, and may underlie, many aspects of primary sensory processing and short-term memory. Activity in the gamma band (30 Hz up to > 100 Hz) is associated with such cognitive tasks and is thought to provide a substrate for temporal coupling of spatially separate regions of the brain. However, such coupling requires close matching of frequencies in co-active areas, and because the nominal gamma band is so spectrally broad, it may not constitute a single underlying process. Here we show that, for inhibition-based gamma rhythms in vitro in rat neocortical slices, mechanistically distinct local circuit generators exist in different laminae of rat primary auditory cortex. A persistent, 30 – 45 Hz, gap-junction-dependent gamma rhythm dominates rhythmic activity in supragranular layers 2/3, whereas a tonic depolarization-dependent, 50 – 80 Hz, pyramidal/interneuron gamma rhythm is expressed in granular layer 4 with strong glutamatergic excitation. As a consequence, altering the degree of excitation of the auditory cortex causes bifurcation in the gamma frequency spectrum and can effectively switch temporal control of layer 5 from supragranular to granular layers. Computational modeling predicts the pattern of interlaminar connections may help to stabilize this bifurcation. The data suggest that different strategies are used by primary auditory cortex to represent weak and strong inputs, with principal cell firing rate becoming increasingly important as excitation strength increases. PMID:22114273

  9. Sleep and circadian rhythm disturbance in bipolar disorder.

    Science.gov (United States)

    Bradley, A J; Webb-Mitchell, R; Hazu, A; Slater, N; Middleton, B; Gallagher, P; McAllister-Williams, H; Anderson, K N

    2017-07-01

    Subjective reports of insomnia and hypersomnia are common in bipolar disorder (BD). It is unclear to what extent these relate to underlying circadian rhythm disturbance (CRD). In this study we aimed to objectively assess sleep and circadian rhythm in a cohort of patients with BD compared to matched controls. Forty-six patients with BD and 42 controls had comprehensive sleep/circadian rhythm assessment with respiratory sleep studies, prolonged accelerometry over 3 weeks, sleep questionnaires and diaries, melatonin levels, alongside mood, psychosocial functioning and quality of life (QoL) questionnaires. Twenty-three (50%) patients with BD had abnormal sleep, of whom 12 (52%) had CRD and 29% had obstructive sleep apnoea. Patients with abnormal sleep had lower 24-h melatonin secretion compared to controls and patients with normal sleep. Abnormal sleep/CRD in BD was associated with impaired functioning and worse QoL. BD is associated with high rates of abnormal sleep and CRD. The association between these disorders, mood and functioning, and the direction of causality, warrants further investigation.

  10. Redox rhythm reinforces the circadian clock to gate immune response.

    Science.gov (United States)

    Zhou, Mian; Wang, Wei; Karapetyan, Sargis; Mwimba, Musoki; Marqués, Jorge; Buchler, Nicolas E; Dong, Xinnian

    2015-07-23

    Recent studies have shown that in addition to the transcriptional circadian clock, many organisms, including Arabidopsis, have a circadian redox rhythm driven by the organism's metabolic activities. It has been hypothesized that the redox rhythm is linked to the circadian clock, but the mechanism and the biological significance of this link have only begun to be investigated. Here we report that the master immune regulator NPR1 (non-expressor of pathogenesis-related gene 1) of Arabidopsis is a sensor of the plant's redox state and regulates transcription of core circadian clock genes even in the absence of pathogen challenge. Surprisingly, acute perturbation in the redox status triggered by the immune signal salicylic acid does not compromise the circadian clock but rather leads to its reinforcement. Mathematical modelling and subsequent experiments show that NPR1 reinforces the circadian clock without changing the period by regulating both the morning and the evening clock genes. This balanced network architecture helps plants gate their immune responses towards the morning and minimize costs on growth at night. Our study demonstrates how a sensitive redox rhythm interacts with a robust circadian clock to ensure proper responsiveness to environmental stimuli without compromising fitness of the organism.

  11. A New Perspective for Parkinson's Disease: Circadian Rhythm.

    Science.gov (United States)

    Li, Siyue; Wang, Yali; Wang, Fen; Hu, Li-Fang; Liu, Chun-Feng

    2017-02-01

    Circadian rhythm is manifested by the behavioral and physiological changes from day to night, which is controlled by the pacemaker and its regulator. The former is located at the suprachiasmatic nuclei (SCN) in the anterior hypothalamus, while the latter is composed of clock genes present in all tissues. Circadian desynchronization influences normal patterns of day-night rhythms such as sleep and alertness cycles, rest and activity cycles. Parkinson's disease (PD) exhibits diurnal fluctuations. Circadian dysfunction has been observed in PD patients and animal models, which may result in negative consequences to the homeostasis and even exacerbate the disease progression. Therefore, circadian therapies, including light stimulation, physical activity, dietary and social schedules, may be helpful for PD patients. However, the cellular and molecular mechanisms that underlie the circadian dysfunction in PD remain elusive. Further research on circadian patterns is needed. This article summarizes the existing research on the circadian rhythms in PD, focusing on the clinical symptom variations, molecular changes, as well as the available treatment options.

  12. Speech rhythm facilitates syntactic ambiguity resolution: ERP evidence.

    Directory of Open Access Journals (Sweden)

    Maria Paula Roncaglia-Denissen

    Full Text Available In the current event-related potential (ERP study, we investigated how speech rhythm impacts speech segmentation and facilitates the resolution of syntactic ambiguities in auditory sentence processing. Participants listened to syntactically ambiguous German subject- and object-first sentences that were spoken with either regular or irregular speech rhythm. Rhythmicity was established by a constant metric pattern of three unstressed syllables between two stressed ones that created rhythmic groups of constant size. Accuracy rates in a comprehension task revealed that participants understood rhythmically regular sentences better than rhythmically irregular ones. Furthermore, the mean amplitude of the P600 component was reduced in response to object-first sentences only when embedded in rhythmically regular but not rhythmically irregular context. This P600 reduction indicates facilitated processing of sentence structure possibly due to a decrease in processing costs for the less-preferred structure (object-first. Our data suggest an early and continuous use of rhythm by the syntactic parser and support language processing models assuming an interactive and incremental use of linguistic information during language processing.

  13. Speech rhythm facilitates syntactic ambiguity resolution: ERP evidence.

    Science.gov (United States)

    Roncaglia-Denissen, Maria Paula; Schmidt-Kassow, Maren; Kotz, Sonja A

    2013-01-01

    In the current event-related potential (ERP) study, we investigated how speech rhythm impacts speech segmentation and facilitates the resolution of syntactic ambiguities in auditory sentence processing. Participants listened to syntactically ambiguous German subject- and object-first sentences that were spoken with either regular or irregular speech rhythm. Rhythmicity was established by a constant metric pattern of three unstressed syllables between two stressed ones that created rhythmic groups of constant size. Accuracy rates in a comprehension task revealed that participants understood rhythmically regular sentences better than rhythmically irregular ones. Furthermore, the mean amplitude of the P600 component was reduced in response to object-first sentences only when embedded in rhythmically regular but not rhythmically irregular context. This P600 reduction indicates facilitated processing of sentence structure possibly due to a decrease in processing costs for the less-preferred structure (object-first). Our data suggest an early and continuous use of rhythm by the syntactic parser and support language processing models assuming an interactive and incremental use of linguistic information during language processing.

  14. The Paradox of Isochrony in the Evolution of Human Rhythm

    Directory of Open Access Journals (Sweden)

    Andrea Ravignani

    2017-11-01

    Full Text Available Isochrony is crucial to the rhythm of human music. Some neural, behavioral and anatomical traits underlying rhythm perception and production are shared with a broad range of species. These may either have a common evolutionary origin, or have evolved into similar traits under different evolutionary pressures. Other traits underlying rhythm are rare across species, only found in humans and few other animals. Isochrony, or stable periodicity, is common to most human music, but isochronous behaviors are also found in many species. It appears paradoxical that humans are particularly good at producing and perceiving isochronous patterns, although this ability does not conceivably confer any evolutionary advantage to modern humans. This article will attempt to solve this conundrum. To this end, we define the concept of isochrony from the present functional perspective of physiology, cognitive neuroscience, signal processing, and interactive behavior, and review available evidence on isochrony in the signals of humans and other animals. We then attempt to resolve the paradox of isochrony by expanding an evolutionary hypothesis about the function that isochronous behavior may have had in early hominids. Finally, we propose avenues for empirical research to examine this hypothesis and to understand the evolutionary origin of isochrony in general.

  15. Alignment strategies for the entrainment of music and movement rhythms.

    Science.gov (United States)

    Moens, Bart; Leman, Marc

    2015-03-01

    Theories of entrainment assume that spontaneous entrainment emerges from dynamic laws that operate via mediators on interactions, whereby entrainment is facilitated if certain conditions are fulfilled. In this study, we show that mediators can be built that affect the entrainment of human locomotion to music. More specifically, we built D-Jogger, a music player that functions as a mediator between music and locomotion rhythms. The D-Jogger makes it possible to manipulate the timing differences between salient moments of the rhythms (beats and footfalls) through the manipulation of the musical period and phase, which affect the condition in which entrainment functions. We conducted several experiments to explore different strategies for manipulating the entrainment of locomotion and music. The results of these experiments showed that spontaneous entrainment can be manipulated, thereby suggesting different strategies on how to embark. The findings furthermore suggest a distinction among different modalities of entrainment: finding the beat (the most difficult part of entrainment), keeping the beat (easier, as a temporal scheme has been established), and being in phase (no entrainment is needed because the music is always adapted to the human rhythm). This study points to a new avenue of research on entrainment and opens new perspectives for the neuroscience of music. © 2014 New York Academy of Sciences.

  16. Daily rhythm of phosphoenolpyruvate carboxylase in Crassulacean acid metabolism plants : Immunological evidence for the absence of a rhythm in protein synthesis.

    Science.gov (United States)

    Brulfert, J; Vidal, J; Gadal, P; Queiroz, O

    1982-11-01

    Immunotitration of phosphoenolpyruvate carboxylase (EC 4.1.1.31) extracted from leaves of Kalanchoe blossfeldiana v. Poelln. cv. Tom Thumb. It was established that at different times of the day-night cycle the daily rhythm of enzyme capacity does not result from a rhythm in protein synthesis, but rather from changes in the specific activity of the enzyme.

  17. Methodic of perfection of higher pedagogical educational establishments girl students’ rhythm

    Directory of Open Access Journals (Sweden)

    A.N. Kolumbet

    2016-06-01

    Full Text Available Purpose: to study influence of methodic of rhythm perfection on girl students’ coordination abilities. Material: in the research 264 girl students participated. We assessed individual and collective rhythm, internal and external motor rhythm; rhythm in exercises with musical accompaniment. Results: we have determined that creative motor tasks require variable conditions for their realization. We have proved demand in appropriate criteria for their assessment. It is noted that there is a demand in development of rhythm, considering its main kinds and manifestations, which are formed with some peculiarities. Individual rhythm is determined by activation of attention and its level. It is perfected more successfully rather with stimulated development than with natural. It was found that with age the character of natural progressing of rhythm preserves. Conclusions: it is recommended to develop rhythm in compliance with its kinds and manifestations. Progressing and perfection of rhythm is a long lasted process and shall be realized during all period of girl students’ studying. Such approach forms girl students’ demand in finding of purposeful motor rhythm in all their new motor actions. It ensures optimality of their fulfillment.

  18. Ecological assessment of seasonal bioclimatic and production rhythms in agrosystems of the Republic of Armenia

    Directory of Open Access Journals (Sweden)

    Arsen Grigoryan

    2017-06-01

    Full Text Available In the article the time features of occurrence of bioclimatic and industrial rhythms according to altitudinal belts are analyzed, a nomogram is composed and spatial and time patterns of rhythms are revealed, the ways of the rational use of seasonal rhythms and greening agrosystems of the Republic of Armenia (RA are shown. The paper summarizes 80–100-year summer monitoring data on onset timing of the main seasonal bioclimatic rhythms of animate and inanimate nature in the RA. The definition of bioclimatic rhythms is given. The importance of studies of seasonal rhythms of nature and society, especially in the non-tropical zones of the Earth is shown. Besides, the special importance of bioclimatic seasonal rhythms' study in order to optimize agro-zootechnical activities and to green agricultural systems is emphasized. Continuous chain of natural rhythms leads to the formation of adequate seasonal rhythms in the production activities of all sectors of the economy, ensuring the functioning of the biosphere and society. The regularities of the timing of seasonal bioclimatic rhythms' onset by the vertical zones in Armenia taking into account the atmospheric moisture of regions is set, vertical gradients are calculated and a nomogram allowing to develop calendars of seasonal works being carried out in certain regions is drawn.

  19. Reviewing the musical component of rhythm of "poetry" and the factors influencing it

    Directory of Open Access Journals (Sweden)

    Ma’sumeh Ma’dankan

    2017-04-01

    Full Text Available ‘Rhythm’ is the most important component in the music of poetry. In this paper, in addition to defining rhythm, we have studied relative components which have most influence on the music of poetry. ‘Rhythm’ is the first common factor in different arts especially music and poetry. Poetry has always been along with rhythm. A short and complete definition of ‘rhythm’ is: “Rhythm is the balance resulting from sequence of letters or rhythms at certain limited times”.The most important factors affecting rhythm are: Proportion of syllables at prosodic rhythms: Every syllable has its special musical load at prosodic rhythms. It is clear that if each of them is mostly used at one rhythm, it will mostly and clearly show its own special state. Sequence of syllables at prosodic rhythms: Succession of long or short syllables because of their special vocal effect on rhythm is very effective on the musical quality of rhythm. Application of long syllable: The most the number of long syllables in a verse, the heavier will be the rhythm of the verse. Because in this way the number of syllables of every verse will be decreased and their temporal duration will be increased. Conformity of the end of words with the end of elements (space between words with space between elements: conformity of the end of words and elements because of the repeated sequence of an element highly strengthens the effect of that prosodic element at the mind of the listener. These constant and repeated scansions make the poem rhythmic and enrich its music. Making accidental or the second rhythm: one way for innovation and overcoming the natural music of a rhythm is making a special rhythm other than the main prosodic rhythm of poem by arranging the words in a special order in a way that it conforms to the other scansion of the same prosodic rhythm. Using regular space between words other than space of elements: sometimes the poet without using a different scansion of the

  20. Circadian rhythms on skin function of hairless rats: light and thermic influences.

    Science.gov (United States)

    Flo, Ana; Díez-Noguera, Antoni; Calpena, Ana C; Cambras, Trinitat

    2014-03-01

    Circadian rhythms are present in most functions of living beings. We have demonstrated the presence of circadian rhythms in skin variables (transepidermal water loss, TEWL; stratum corneum hydration, SCH; and skin temperature) in hairless rats under different environmental conditions of light and temperature. Circadian rhythms in TEWL and SCH showed mean amplitudes of about 20% and 14% around the mean, respectively, and appeared under light-dark cycles as well as under constant darkness. Environmental temperature was able to override TEWL, but not SCH rhythm, evidencing the dependency of TEWL on the temperature. Mean daily values of TEWL and SCH, and also the amplitude of TEWL rhythm, increased with the age of the animal. Under constant light, situation that induces arrhythmicity in rats, SCH and TEWL were inversely correlated. The results suggest the importance to take into account the functional skin rhythms in research in dermatological sciences. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Rhythm recognition is accountable for the majority of hands-off time during cardiopulmonary resuscitation

    DEFF Research Database (Denmark)

    Hansen, Lars Koch; Brabrand, Mikkel

    2014-01-01

    or not was 3.4 s [95% confidence interval (CI): 2.8-3.9] for shockable and 4.4 s (95% CI: 3.6-5.3) for nonshockable rhythms (P4.0 s (95% CI: 3.5-4.5). Of all shockable rhythms, 95.2 % were correctly diagnosed as shockable, compared with 88.6 % of nonshockable rhythms...

  2. Stochastic Alternating Dynamics for Synchronous EAD-Like Beating Rhythms in Cultured Cardiac Myocytes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ning; ZHANG Hui-Min; LIU Zhi-Qiang; DING Xue-Li; YANG Ming-Hao; GU Hua-Guang; REN Wei

    2009-01-01

    Dissolved cardiac myocytes can couple together and generate synchronous beatings in culture. We observed a synchronized early after-depolarization(EAD)-like rhythm in cultured cardiac myocytes and reproduced the experimental observation in a network mathematical model whose dynamics are close to a Hopf bifurcation. The mechanism for this EAD-like rhythm is attributed to noised-induced stochastic alternatings between the focus and the limit cycle. These results provide novel understandings for pathological heart rhythms like the early immature beatings.

  3. Biological rhythm in 1/f fluctuations of heart rate in asthmatic children

    Directory of Open Access Journals (Sweden)

    Norio Kazuma

    2004-01-01

    Conclusion: During an asthma attack, the rhythm of 1/f fluctuations is ultradian (cycle length under 20 h, compared with various rhythms during a non-attack period. In future, we will clarify the relevance of the ultradian rhythm of 1/f fluctuations over a 24 h period and the biological life-support system at a point of time of an asthma attack.

  4. Effects of exercise on circadian rhythms and mobility in aging Drosophila melanogaster

    OpenAIRE

    Rakshit, Kuntol; Wambua, Rebecca; Giebultowicz, Tomasz M.; Giebultowicz, Jadwiga M.

    2013-01-01

    Daily life functions such as sleep and feeding oscillate with circa 24 h period due to endogenous circadian rhythms generated by circadian clocks. Genetic or environmental disruption of circadian rhythms is associated with various aging-related phenotypes. Circadian rhythms decay during normal aging, and there is a need to explore strategies that could avert age-related changes in the circadian system. Exercise was reported to delay aging in mammals. Here, we investigated whether daily exerci...

  5. Impact of chronodisruption during primate pregnancy on the maternal and newborn temperature rhythms.

    Directory of Open Access Journals (Sweden)

    María Serón-Ferré

    Full Text Available Disruption of the maternal environment during pregnancy is a key contributor to offspring diseases that develop in adult life. To explore the impact of chronodisruption during pregnancy in primates, we exposed pregnant capuchin monkeys to constant light (eliminating the maternal melatonin rhythm from the last third of gestation to term. Maternal temperature and activity circadian rhythms were assessed as well as the newborn temperature rhythm. Additionally we studied the effect of daily maternal melatonin replacement during pregnancy on these rhythms. Ten pregnant capuchin monkeys were exposed to constant light from 60% of gestation to term. Five received a daily oral dose of melatonin (250 µg kg/body weight at 1800 h (LL+Mel and the other five a placebo (LL. Six additional pregnant females were maintained in a 14∶10 light:dark cycles and their newborns were used as controls (LD. Rhythms were recorded 96 h before delivery in the mother and at 4-6 days of age in the newborn. Exposure to constant light had no effect on the maternal body temperature rhythm however it delayed the acrophase of the activity rhythm. Neither rhythm was affected by melatonin replacement. In contrast, maternal exposure to constant light affected the newborn body temperature rhythm. This rhythm was entrained in control newborns whereas LL newborns showed a random distribution of the acrophases over 24-h. In addition, mean temperature was decreased (34.0±0.6 vs 36.1±0.2°C, in LL and control, respectively P<0.05. Maternal melatonin replacement during pregnancy re-synchronized the acrophases and restored mean temperature to the values in control newborns. Our findings demonstrate that prenatal melatonin is a Zeitgeber for the newborn temperature rhythm and supports normal body temperature maintenance. Altogether these prenatal melatonin effects highlight the physiological importance of the maternal melatonin rhythm during pregnancy for the newborn primate.

  6. The maturation of cortical sleep rhythms and networks over early development

    OpenAIRE

    Chu, Catherine Jean; Leahy, J.; Pathmanathan, Jay Sriram; Kramer, M.A.; Cash, Sydney S.

    2014-01-01

    Objective: Although neuronal activity drives all aspects of cortical development, how human brain rhythms spontaneously mature remains an active area of research. We sought to systematically evaluate the emergence of human brain rhythms and functional cortical networks over early development. Methods: We examined cortical rhythms and coupling patterns from birth through adolescence in a large cohort of healthy children (n=384) using scalp electroencephalogram (EEG) in the sleep state. ...

  7. Maternal and infant activity: Analytic approaches for the study of circadian rhythm.

    Science.gov (United States)

    Thomas, Karen A; Burr, Robert L; Spieker, Susan

    2015-11-01

    The study of infant and mother circadian rhythm entails choice of instruments appropriate for use in the home environment as well as selection of analytic approach that characterizes circadian rhythm. While actigraphy monitoring suits the needs of home study, limited studies have examined mother and infant rhythm derived from actigraphy. Among this existing research a variety of analyses have been employed to characterize 24-h rhythm, reducing ability to evaluate and synthesize findings. Few studies have examined the correspondence of mother and infant circadian parameters for the most frequently cited approaches: cosinor, non-parametric circadian rhythm analysis (NPCRA), and autocorrelation function (ACF). The purpose of this research was to examine analytic approaches in the study of mother and infant circadian activity rhythm. Forty-three healthy mother and infant pairs were studied in the home environment over a 72h period at infant age 4, 8, and 12 weeks. Activity was recorded continuously using actigraphy monitors and mothers completed a diary. Parameters of circadian rhythm were generated from cosinor analysis, NPCRA, and ACF. The correlation among measures of rhythm center (cosinor mesor, NPCRA mid level), strength or fit of 24-h period (cosinor magnitude and R(2), NPCRA amplitude and relative amplitude (RA)), phase (cosinor acrophase, NPCRA M10 and L5 midpoint), and rhythm stability and variability (NPCRA interdaily stability (IS) and intradaily variability (IV), ACF) was assessed, and additionally the effect size (eta(2)) for change over time evaluated. Results suggest that cosinor analysis, NPCRA, and autocorrelation provide several comparable parameters of infant and maternal circadian rhythm center, fit, and phase. IS and IV were strongly correlated with the 24-h cycle fit. The circadian parameters analyzed offer separate insight into rhythm and differing effect size for the detection of change over time. Findings inform selection of analysis and

  8. Circadian locomotor rhythms in the cricket, Gryllodes sigillatus. I. Localization of the pacemaker and the photoreceptor.

    Science.gov (United States)

    Abe, Y; Ushirogawa, H; Tomioka, K

    1997-10-01

    Circadian locomotor rhythm and its underlying mechanism were investigated in the cricket, Gryllodes sigillatus. Adult male crickets showed a nocturnal locomotor rhythm peaking early in the dark phase of a light to dark cycle. This rhythm persisted under constant darkness (DD) with a free-running period averaging 23.1 +/- 0.3 hr. Although constant bright light made most animals arrhythmic, about 40% of the animals showed free-running rhythms with a period longer than 24 hr under constant dim light condition. On transfer to DD, all arrhythmic animals restored the locomotor rhythm. Bilateral optic nerve severance resulted in free-running of the rhythm even under light-dark cycles. The free-running period of the optic nerve severed animals was significantly longer than sham operated crickets in DD, suggesting that the compound eye plays some role in determining the free-running period. Removal of bilateral lamina-medulla portion of the optic lobe abolished the rhythm under DD. These results demonstrate that the photoreceptor for entrainment is the compound eye and the optic lobe is indispensable for persistence of the rhythm. However, 75% and 54% of the optic lobeless animals showed aberrant rhythms with a period very close to 24 hr under light and temperature cycles, respectively, suggesting that there are neural and/or humoral mechanisms for the aberrant rhythms outside of the optic lobe. Since ocelli removal did not affect the photoperiodically induced rhythm, it is likely that the photoreception for the rhythm is performed through an extraretinal photoreceptor.

  9. Resonance of about-weekly human heart rate rhythm with solar activity change.

    Science.gov (United States)

    Cornelissen, G; Halberg, F; Wendt, H W; Bingham, C; Sothern, R B; Haus, E; Kleitman, E; Kleitman, N; Revilla, M A; Revilla, M; Breus, T K; Pimenov, K; Grigoriev, A E; Mitish, M D; Yatsyk, G V; Syutkina, E V

    1996-12-01

    In several human adults, certain solar activity rhythms may influence an about 7-day rhythm in heart rate. When no about-weekly feature was found in the rate of change in sunspot area, a measure of solar activity, the double amplitude of a circadian heart rate rhythm, approximated by the fit of a 7-day cosine curve, was lower, as was heart rate corresponds to about-weekly features in solar activity and/or relates to a sunspot cycle.

  10. Distractor Effect of Auditory Rhythms on Self-Paced Tapping in Chimpanzees and Humans

    Science.gov (United States)

    Hattori, Yuko; Tomonaga, Masaki; Matsuzawa, Tetsuro

    2015-01-01

    Humans tend to spontaneously align their movements in response to visual (e.g., swinging pendulum) and auditory rhythms (e.g., hearing music while walking). Particularly in the case of the response to auditory rhythms, neuroscientific research has indicated that motor resources are also recruited while perceiving an auditory rhythm (or regular pulse), suggesting a tight link between the auditory and motor systems in the human brain. However, the evolutionary origin of spontaneous responses to auditory rhythms is unclear. Here, we report that chimpanzees and humans show a similar distractor effect in perceiving isochronous rhythms during rhythmic movement. We used isochronous auditory rhythms as distractor stimuli during self-paced alternate tapping of two keys of an electronic keyboard by humans and chimpanzees. When the tempo was similar to their spontaneous motor tempo, tapping onset was influenced by intermittent entrainment to auditory rhythms. Although this effect itself is not an advanced rhythmic ability such as dancing or singing, our results suggest that, to some extent, the biological foundation for spontaneous responses to auditory rhythms was already deeply rooted in the common ancestor of chimpanzees and humans, 6 million years ago. This also suggests the possibility of a common attentional mechanism, as proposed by the dynamic attending theory, underlying the effect of perceiving external rhythms on motor movement. PMID:26132703

  11. Autism as a disorder of biological and behavioral rhythms: Towards new therapeutic perspectives

    Directory of Open Access Journals (Sweden)

    Sylvie eTordjman

    2015-02-01

    Full Text Available There is a growing interest in the role of biological and behavioral rhythms in typical and atypical development. Recent studies in cognitive and developmental psychology have highlighted the importance of rhythmicity and synchrony of motor, emotional and relational rhythms in early development of social communication. The synchronization of rhythms allows tuning and adaptation to the external environment. The role of melatonin in the ontogenetic establishment of circadian rhythms and the synchronization of peripheral oscillators suggests that this hormone might be also involved in the synchrony of motor, emotional and relational rhythms. Autism provides a challenging model of physiological and behavioral rhythm disturbances and their possible effects on the development of social communication impairments and repetitive behaviors or interests. This article situates autism as a disorder of biological and behavioral rhythms and reviews the recent literature on the role of rhythmicity and synchrony of rhythms in child development. Finally, the hypothesis is developed that an integrated approach focusing on biological, motor, emotional and relational rhythms may open interesting therapeutic perspectives for children with autism. More specifically, promising avenues are discussed for potential therapeutic benefits in autism spectrum disorder of melatonin combined with developmental behavioral interventions that emphasize synchrony such as the Early Start Denver Model (ESDM.

  12. Autism as a disorder of biological and behavioral rhythms: toward new therapeutic perspectives.

    Science.gov (United States)

    Tordjman, Sylvie; Davlantis, Katherine S; Georgieff, Nicolas; Geoffray, Marie-Maude; Speranza, Mario; Anderson, George M; Xavier, Jean; Botbol, Michel; Oriol, Cécile; Bellissant, Eric; Vernay-Leconte, Julie; Fougerou, Claire; Hespel, Anne; Tavenard, Aude; Cohen, David; Kermarrec, Solenn; Coulon, Nathalie; Bonnot, Olivier; Dawson, Geraldine

    2015-01-01

    There is a growing interest in the role of biological and behavioral rhythms in typical and atypical development. Recent studies in cognitive and developmental psychology have highlighted the importance of rhythmicity and synchrony of motor, emotional, and interpersonal rhythms in early development of social communication. The synchronization of rhythms allows tuning and adaptation to the external environment. The role of melatonin in the ontogenetic establishment of circadian rhythms and the synchronization of the circadian clocks network suggests that this hormone might be also involved in the synchrony of motor, emotional, and interpersonal rhythms. Autism provides a challenging model of physiological and behavioral rhythm disturbances and their possible effects on the development of social communication impairments and repetitive behaviors and interests. This article situates autism as a disorder of biological and behavioral rhythms and reviews the recent literature on the role of rhythmicity and synchrony of rhythms in child development. Finally, the hypothesis is developed that an integrated approach focusing on biological, motor, emotional, and interpersonal rhythms may open interesting therapeutic perspectives for children with autism. More specifically, promising avenues are discussed for potential therapeutic benefits in autism spectrum disorder of melatonin combined with developmental behavioral interventions that emphasize synchrony, such as the Early Start Denver Model.

  13. Neurospora circadian rhythms in space - A reexamination of the endogenous-exogenous question

    Science.gov (United States)

    Sulzman, F. M.; Ellman, D.; Wassmer, G.; Fuller, C. A.; Moore-Ede, M.

    1984-01-01

    To test the functioning of circadian rhythms removed from periodicities of the earth's 24-hour rotation, the conidiation rhythm of the fungus Neurospora crassa was monitored in constant darkness during spaceflight. The free-running period of the rhythm was the same in space as on the earth, but there was a marked reduction in the clarity of the rhythm, and apparent arrhythmicity in some tubes. At the current stage of analysis of the results there is insufficient evidence to determine whether the effect seen in space was related to removal from 24-hour periodicities and whether the circadian timekeeping mechanism, or merely its expression, was affected.

  14. Distractor Effect of Auditory Rhythms on Self-Paced Tapping in Chimpanzees and Humans.

    Directory of Open Access Journals (Sweden)

    Yuko Hattori

    Full Text Available Humans tend to spontaneously align their movements in response to visual (e.g., swinging pendulum and auditory rhythms (e.g., hearing music while walking. Particularly in the case of the response to auditory rhythms, neuroscientific research has indicated that motor resources are also recruited while perceiving an auditory rhythm (or regular pulse, suggesting a tight link between the auditory and motor systems in the human brain. However, the evolutionary origin of spontaneous responses to auditory rhythms is unclear. Here, we report that chimpanzees and humans show a similar distractor effect in perceiving isochronous rhythms during rhythmic movement. We used isochronous auditory rhythms as distractor stimuli during self-paced alternate tapping of two keys of an electronic keyboard by humans and chimpanzees. When the tempo was similar to their spontaneous motor tempo, tapping onset was influenced by intermittent entrainment to auditory rhythms. Although this effect itself is not an advanced rhythmic ability such as dancing or singing, our results suggest that, to some extent, the biological foundation for spontaneous responses to auditory rhythms was already deeply rooted in the common ancestor of chimpanzees and humans, 6 million years ago. This also suggests the possibility of a common attentional mechanism, as proposed by the dynamic attending theory, underlying the effect of perceiving external rhythms on motor movement.

  15. Distractor Effect of Auditory Rhythms on Self-Paced Tapping in Chimpanzees and Humans.

    Science.gov (United States)

    Hattori, Yuko; Tomonaga, Masaki; Matsuzawa, Tetsuro

    2015-01-01

    Humans tend to spontaneously align their movements in response to visual (e.g., swinging pendulum) and auditory rhythms (e.g., hearing music while walking). Particularly in the case of the response to auditory rhythms, neuroscientific research has indicated that motor resources are also recruited while perceiving an auditory rhythm (or regular pulse), suggesting a tight link between the auditory and motor systems in the human brain. However, the evolutionary origin of spontaneous responses to auditory rhythms is unclear. Here, we report that chimpanzees and humans show a similar distractor effect in perceiving isochronous rhythms during rhythmic movement. We used isochronous auditory rhythms as distractor stimuli during self-paced alternate tapping of two keys of an electronic keyboard by humans and chimpanzees. When the tempo was similar to their spontaneous motor tempo, tapping onset was influenced by intermittent entrainment to auditory rhythms. Although this effect itself is not an advanced rhythmic ability such as dancing or singing, our results suggest that, to some extent, the biological foundation for spontaneous responses to auditory rhythms was already deeply rooted in the common ancestor of chimpanzees and humans, 6 million years ago. This also suggests the possibility of a common attentional mechanism, as proposed by the dynamic attending theory, underlying the effect of perceiving external rhythms on motor movement.

  16. "Bird Song Metronomics": Isochronous Organization of Zebra Finch Song Rhythm.

    Science.gov (United States)

    Norton, Philipp; Scharff, Constance

    2016-01-01

    The human capacity for speech and vocal music depends on vocal imitation. Songbirds, in contrast to non-human primates, share this vocal production learning with humans. The process through which birds and humans learn many of their vocalizations as well as the underlying neural system exhibit a number of striking parallels and have been widely researched. In contrast, rhythm, a key feature of language, and music, has received surprisingly little attention in songbirds. Investigating temporal periodicity in bird song has the potential to inform the relationship between neural mechanisms and behavioral output and can also provide insight into the biology and evolution of musicality. Here we present a method to analyze birdsong for an underlying rhythmic regularity. Using the intervals from one note onset to the next as input, we found for each bird an isochronous sequence of time stamps, a "signal-derived pulse," or pulse(S), of which a subset aligned with all note onsets of the bird's song. Fourier analysis corroborated these results. To determine whether this finding was just a byproduct of the duration of notes and intervals typical for zebra finches but not dependent on the individual duration of elements and the sequence in which they are sung, we compared natural songs to models of artificial songs. Note onsets of natural song deviated from the pulse(S) significantly less than those of artificial songs with randomized note and gap durations. Thus, male zebra finch song has the regularity required for a listener to extract a perceived pulse (pulse(P)), as yet untested. Strikingly, in our study, pulses(S) that best fit note onsets often also coincided with the transitions between sub-note elements within complex notes, corresponding to neuromuscular gestures. Gesture durations often equaled one or more pulse(S) periods. This suggests that gesture duration constitutes the basic element of the temporal hierarchy of zebra finch song rhythm, an interesting parallel

  17. Daily rhythms of the sleep-wake cycle

    Directory of Open Access Journals (Sweden)

    Waterhouse Jim

    2012-03-01

    Full Text Available Abstract The amount and timing of sleep and sleep architecture (sleep stages are determined by several factors, important among which are the environment, circadian rhythms and time awake. Separating the roles played by these factors requires specific protocols, including the constant routine and altered sleep-wake schedules. Results from such protocols have led to the discovery of the factors that determine the amounts and distribution of slow wave and rapid eye movement sleep as well as to the development of models to determine the amount and timing of sleep. One successful model postulates two processes. The first is process S, which is due to sleep pressure (and increases with time awake and is attributed to a 'sleep homeostat'. Process S reverses during slow wave sleep (when it is called process S'. The second is process C, which shows a daily rhythm that is parallel to the rhythm of core temperature. Processes S and C combine approximately additively to determine the times of sleep onset and waking. The model has proved useful in describing normal sleep in adults. Current work aims to identify the detailed nature of processes S and C. The model can also be applied to circumstances when the sleep-wake cycle is different from the norm in some way. These circumstances include: those who are poor sleepers or short sleepers; the role an individual's chronotype (a measure of how the timing of the individual's preferred sleep-wake cycle compares with the average for a population; and changes in the sleep-wake cycle with age, particularly in adolescence and aging, since individuals tend to prefer to go to sleep later during adolescence and earlier in old age. In all circumstances, the evidence that sleep times and architecture are altered and the possible causes of these changes (including altered S, S' and C processes are examined.

  18. Chronotherapeutic drug delivery systems: an approach to circadian rhythms diseases.

    Science.gov (United States)

    Sunil, S A; Srikanth, M V; Rao, N Sreenivasa; Uhumwangho, M U; Latha, K; Murthy, K V Ramana

    2011-11-01

    The purpose of writing this review on chronotherapeutic drug delivery systems (ChrDDs) is to review the literatures with special focus on ChrDDs and the various dosage forms, techniques that are used to target the circadian rhythms (CR) of various diseases. Many functions of the human body vary considerably in a day. ChrDDs refers to a treatment method in which in vivo drug availability is timed to match circadian rhythms of disease in order to optimize therapeutic outcomes and minimize side effects. Several techniques have been developed but not many dosage forms for all the diseases are available in the market. ChrDDs are gaining importance in the field of pharmaceutical technology as these systems reduce dosing frequency, toxicity and deliver the drug that matches the CR of that particular disease when the symptoms are maximum to worse. Finally, the ultimate benefit goes to the patient due the compliance and convenience of the dosage form. Some diseases that follow circadian rhythms include cardiovascular diseases, asthma, arthritis, ulcers, diabetes etc. ChrDDs in the market were also discussed and the current technologies used to formulate were also stated. These technologies include Contin® , Chronotopic®, Pulsincaps®, Ceform®, Timerx®, Oros®, Codas®, Diffucaps®, Egalet®, Tablet in capsule device, Core-in-cup tablet technology. A coated drug-core tablet matrix, A bi-layered tablet, Multiparticulate-based chronotherapeutic drug delivery systems, Chronoset and Controlled release microchips.

  19. Communication of genetic information to families with inherited rhythm disorders.

    Science.gov (United States)

    Burns, Charlotte; James, Cynthia; Ingles, Jodie

    2017-11-23

    Given the dynamic nature of the electrical activity of the heart and ongoing challenges in the diagnostics of inherited heart rhythm disorders, genetic information can be a vital aspect of family management. Communication of genetic information is complex, and the responsibility to convey this information to the family lies with the proband. Current practice falls short, requiring additional support from the clinician and multidisciplinary team. Communication is a 2-part iterative process, reliant on both the understanding of the probands and their ability to effectively communicate with relatives. With the surge of high-throughput genetic testing, results generated are increasingly complex, making the task of communication more challenging. Here we discuss 3 key issues. First, the probabilistic nature of genetic test results means uncertainty is inherent to the practice. Second, secondary findings may arise. Third, personal preferences, values, and family dynamics also come into play and must be acknowledged when considering how best to support effective communication. Here we provide insight into the challenges and provide practical advice for clinicians to support effective family communication. These strategies include acknowledging and managing genetic uncertainty, genetic counseling and informed consent, and consideration of personal and familial barriers to effective communication. We will explore the potential for developing resources to assist clinicians in providing patients with sufficient knowledge and support to communicate complex information to their at-risk relatives. Specialized multidisciplinary clinics remain the best equipped to manage patients and families with inherited heart rhythm disorders given the need for a high level of information and support. Copyright © 2017 Heart Rhythm Society. All rights reserved.

  20. Circadian rhythms in effects of hypnotics and sleep inducers.

    Science.gov (United States)

    Reinberg, A

    1986-01-01

    Chronopharmacology involves the investigation of drug effects as a function of biological time and the investigation of drug effects on rhythm characteristics. Three new concepts must be considered: (a) the chronokinetics of a drug, embracing rhythmic (circadian) changes in drug bioavailability (or pharmacokinetics) and its excretion (urinary among others); (b) the chronaesthesia of a biosystem to a drug, i.e. circadian changes in the susceptibility of any biosystem to a drug (including organ systems, parasites, etc.); skin and bronchial chronaesthesia to various agents have been documented in man; and (c) the chronergy of a drug, taking into consideration its chronokinetics and the chronaesthesia of the involved organismic biosystems. The term chronergy includes rhythmic changes in the overall effects and in the effectiveness of some drugs. Clinical chronopharmacology is useful for solving problems of drug optimization, i.e. enhancing the desired efficiency of a drug and reducing its undesired effects. Circadian rhythms can be demonstrated in various effects of drugs on sleep, anaesthesia and related processes. For example, in the rat the duration of sleep induced by substances such as pentobarbital, hexobarbital, Althesin (alphaxadone and alphadoline in castor oil) is circadian system stage-dependent. Time-dependent changes of liver enzymes (e.g. hexobarbital oxidase) play a role in these circadian rhythms. The clinical chronopharmacokinetics of benzodiazepines have been documented in man. Chronopharmacologic methods can be used to study desired and undesired hypnotic effects of substances. Such is the case of new antihistamines (anti-H1), which do not induce sleepiness, in either acute or chronic administration. Pertinent also is the problem of intolerance to shift-work. Intolerant shift-workers are subject to internal desynchronization between at least two rhythms (e.g. activity-rest cycle and body temperature). Clinically these workers suffer from sleep

  1. The evolutionary biology of musical rhythm: was Darwin wrong?

    Directory of Open Access Journals (Sweden)

    Aniruddh D Patel

    2014-03-01

    Full Text Available In The Descent of Man, Darwin speculated that our capacity for musical rhythm reflects basic aspects of brain function broadly shared among animals. Although this remains an appealing idea, it is being challenged by modern cross-species research. This research hints that our capacity to synchronize to a beat, i.e., to move in time with a perceived pulse in a manner that is predictive and flexible across a broad range of tempi, may be shared by only a few other species. Is this really the case? If so, it would have important implications for our understanding of the evolution of human musicality.

  2. The evolutionary biology of musical rhythm: was Darwin wrong?

    Science.gov (United States)

    Patel, Aniruddh D

    2014-03-01

    In The Descent of Man, Darwin speculated that our capacity for musical rhythm reflects basic aspects of brain function broadly shared among animals. Although this remains an appealing idea, it is being challenged by modern cross-species research. This research hints that our capacity to synchronize to a beat, i.e., to move in time with a perceived pulse in a manner that is predictive and flexible across a broad range of tempi, may be shared by only a few other species. Is this really the case? If so, it would have important implications for our understanding of the evolution of human musicality.

  3. Group interpersonal and social rhythm therapy for bipolar depression.

    Science.gov (United States)

    Hoberg, Astrid A; Ponto, Julie; Nelson, Pamela J; Frye, Mark A

    2013-10-01

    To evaluate the feasibility of 2-week interpersonal and social rhythm therapy group (IPSRT-G) for bipolar depression. Participants with bipolar depression received two individual sessions, six IPSRT-G sessions, and a 12-week telephone call. The Inventory of Depressive Symptomatology-Clinician Rated (IDS-C), Young Mania Rating Scale (YMRS), Sheehan Disability Scale (SDS), and Clinical Global Impressions-Bipolar Version (CGI-BP) were used. IDS-C and SDS scores improved significantly at 12 weeks. YMRS and CGI-BP scores improved but did not reach statistical significance. The promising antidepressive response supports further study of IPSRT-G for bipolar depression. © 2013 Wiley Periodicals, Inc.

  4. Disturbed mouse circadian rhythm before the Kobe EQ in 1995

    Science.gov (United States)

    Yokoi, Sayoko

    2013-04-01

    Legends of macro-anomalies before large earthquakes have been passed down for generations in Asia. Most of the statements on earthquake precursors are considered unreliable afterthoughts by traditional scientists. However, disturbed biological rhythms in mice were observed before the Kobe EQ in 1995 (Yokoi et al, 2003). The records of unusual mouse behavior before the earthquake were obtained to study biological clock at Institute for Protein Research, Osaka University. It is clarified that the disturbance was very rare phenomena statistically. Similar phenomenon was observed before the Wenchuan earthquake in 2008, too (Li et al, 2009). In the presentation, I will discuss the phenomena as one example of preseismic unusual animal behaviors.

  5. Rhythm-based heartbeat duration normalization for atrial fibrillation detection.

    Science.gov (United States)

    Islam, Md Saiful; Ammour, Nassim; Alajlan, Naif; Aboalsamh, Hatim

    2016-05-01

    Screening of atrial fibrillation (AF) for high-risk patients including all patients aged 65 years and older is important for prevention of risk of stroke. Different technologies such as modified blood pressure monitor, single lead ECG-based finger-probe, and smart phone using plethysmogram signal have been emerging for this purpose. All these technologies use irregularity of heartbeat duration as a feature for AF detection. We have investigated a normalization method of heartbeat duration for improved AF detection. AF is an arrhythmia in which heartbeat duration generally becomes irregularly irregular. From a window of heartbeat duration, we estimate the possible rhythm of the majority of heartbeats and normalize duration of all heartbeats in the window based on the rhythm so that we can measure the irregularity of heartbeats for both AF and non-AF rhythms in the same scale. Irregularity is measured by the entropy of distribution of the normalized duration. Then we classify a window of heartbeats as AF or non-AF by thresholding the measured irregularity. The effect of this normalization is evaluated by comparing AF detection performances using duration with the normalization, without normalization, and with other existing normalizations. Sensitivity and specificity of AF detection using normalized heartbeat duration were tested on two landmark databases available online and compared with results of other methods (with/without normalization) by receiver operating characteristic (ROC) curves. ROC analysis showed that the normalization was able to improve the performance of AF detection and it was consistent for a wide range of sensitivity and specificity for use of different thresholds. Detection accuracy was also computed for equal rates of sensitivity and specificity for different methods. Using normalized heartbeat duration, we obtained 96.38% accuracy which is more than 4% improvement compared to AF detection without normalization. The proposed normalization

  6. [Autism spectrum disorders and mu rhythm. A new neurophysiological view].

    Science.gov (United States)

    Palau-Baduell, Montserrat; Valls-Santasusana, Antonio; Salvadó-Salvadó, Berta

    2011-03-01

    Electroencephalographic studies of subjects with autism spectrum disorders (ASD) provide evidences of brain functional aspects in this pathology. Mu rhythm can be reactive in normal population (mu suppression) to both self-movements and to movements performed by others. These reactivities are considered to be related to mirror neurons activity. Subjects with ASD show significant mu suppression to self-movements but they fail to react to the movements performed by others. These findings support the hypothesis of a dysfunctional mirror neurons system in individuals with ASD. Moreover, dysfunction of mirror neurons would be related to social and communicative impairments, cognitive deficits and impairment imitation skills associated with ASD.

  7. A Statistical Analysis of Rhythm Patterns in Ghaleb Dehlavi’s Sonnets

    Directory of Open Access Journals (Sweden)

    M. Ghazanfari

    Full Text Available Ghaleb Dehlavi is considered as the best-known 13th century Indian poet. Also a writer and researcher, he was a Muslim originally from Touran with Eibak Turk ancestors. He was a pioneer of new styles in Urdu poetry. His poems are written in Urdu as well as Persian. His elaborate prose apart, Dehlavi’s odes and lyrics denote the poet’s noble thoughts and lofty nature. In spite of such traits and amazing proficiency in writing Persian poems, though a non-Persian speaker, the man has remained unknown or ignored in Iran. The present paper seeks to make orientations to Ghaleb Dehlavi by examining the rhythm patterns of his sonnets.Making references to the Indian style, the paper offers a typology and a computational account of rhythms as used in Ghaleb’s poems. It is found that 20 different rhythms are employed to versify a totality of 334 sonnets of which 85 percent are in only six rhythms. These six happen to be so frequently used in Persian too.The most frequent rhythm used by Ghaleb is ‘mafoolon faelaton mafaelon faelon’. Highly employed in Persian sonnets too, this rhythm is so capable of expressing the intended concepts. ‘Mafaelon faalaton mafaelna falon’ is another rhythm of his interest used more frequently in his anthology than in Persian poetry. The rhythm ‘mafoolon mafaelon mafaelon faolon’, vastly used by Saadi and Hafiz, also appeals to Ghaleb.Ghaleb’s application of the octave rhythms ‘raml’ and ‘hazj’, which sound so grave in Persian, suggests his tendency for the Indian style in poetry. However, the rise and fall in the frequency of certain rhythms in his anthology may be viewed as an indication of a retreat from his previously practiced literary style. The only rare rhythm in Ghaleb’s poems is ‘faelaton mafoolon faelaton mafoolon’ first tried in Attar’s sonnets. This rhythm has also been tried by Hafiz, Khajou Kermani, Saeb, Kalim, Feyz Kashani, and Bidel Dehlavi. The rhythm has given a stylistic

  8. Musical rhythm spectra from Bach to Joplin obey a 1/f power law.

    Science.gov (United States)

    Levitin, Daniel J; Chordia, Parag; Menon, Vinod

    2012-03-06

    Much of our enjoyment of music comes from its balance of predictability and surprise. Musical pitch fluctuations follow a 1/f power law that precisely achieves this balance. Musical rhythms, especially those of Western classical music, are considered highly regular and predictable, and this predictability has been hypothesized to underlie rhythm's contribution to our enjoyment of music. Are musical rhythms indeed entirely predictable and how do they vary with genre and composer? To answer this question, we analyzed the rhythm spectra of 1,788 movements from 558 compositions of Western classical music. We found that an overwhelming majority of rhythms obeyed a 1/f(β) power law across 16 subgenres and 40 composers, with β ranging from ∼0.5-1. Notably, classical composers, whose compositions are known to exhibit nearly identical 1/f pitch spectra, demonstrated distinctive 1/f rhythm spectra: Beethoven's rhythms were among the most predictable, and Mozart's among the least. Our finding of the ubiquity of 1/f rhythm spectra in compositions spanning nearly four centuries demonstrates that, as with musical pitch, musical rhythms also exhibit a balance of predictability and surprise that could contribute in a fundamental way to our aesthetic experience of music. Although music compositions are intended to be performed, the fact that the notated rhythms follow a 1/f spectrum indicates that such structure is no mere artifact of performance or perception, but rather, exists within the written composition before the music is performed. Furthermore, composers systematically manipulate (consciously or otherwise) the predictability in 1/f rhythms to give their compositions unique identities.

  9. From the Cover: Musical rhythm spectra from Bach to Joplin obey a 1/f power law

    Science.gov (United States)

    Levitin, Daniel J.; Chordia, Parag; Menon, Vinod

    2012-03-01

    Much of our enjoyment of music comes from its balance of predictability and surprise. Musical pitch fluctuations follow a 1/f power law that precisely achieves this balance. Musical rhythms, especially those of Western classical music, are considered highly regular and predictable, and this predictability has been hypothesized to underlie rhythm's contribution to our enjoyment of music. Are musical rhythms indeed entirely predictable and how do they vary with genre and composer? To answer this question, we analyzed the rhythm spectra of 1,788 movements from 558 compositions of Western classical music. We found that an overwhelming majority of rhythms obeyed a 1/fβ power law across 16 subgenres and 40 composers, with β ranging from ∼0.5-1. Notably, classical composers, whose compositions are known to exhibit nearly identical 1/f pitch spectra, demonstrated distinctive 1/f rhythm spectra: Beethoven's rhythms were among the most predictable, and Mozart's among the least. Our finding of the ubiquity of 1/f rhythm spectra in compositions spanning nearly four centuries demonstrates that, as with musical pitch, musical rhythms also exhibit a balance of predictability and surprise that could contribute in a fundamental way to our aesthetic experience of music. Although music compositions are intended to be performed, the fact that the notated rhythms follow a 1/f spectrum indicates that such structure is no mere artifact of performance or perception, but rather, exists within the written composition before the music is performed. Furthermore, composers systematically manipulate (consciously or otherwise) the predictability in 1/f rhythms to give their compositions unique identities.

  10. Maize global transcriptomics reveals pervasive leaf diurnal rhythms but rhythms in developing ears are largely limited to the core oscillator.

    Directory of Open Access Journals (Sweden)

    Kevin R Hayes

    Full Text Available BACKGROUND: Plant diurnal rhythms are vital environmental adaptations to coordinate internal physiological responses to alternating day-night cycles. A comprehensive view of diurnal biology has been lacking for maize (Zea mays, a major world crop. METHODOLOGY: A photosynthetic tissue, the leaf, and a non-photosynthetic tissue, the developing ear, were sampled under natural field conditions. Genome-wide transcript profiling was conducted on a high-density 105 K Agilent microarray to investigate diurnal rhythms. CONCLUSIONS: In both leaves and ears, the core oscillators were intact and diurnally cycling. Maize core oscillator genes are found to be largely conserved with their Arabidopsis counterparts. Diurnal gene regulation occurs in leaves, with some 23% of expressed transcripts exhibiting a diurnal cycling pattern. These transcripts can be assigned to over 1700 gene ontology functional terms, underscoring the pervasive impact of diurnal rhythms on plant biology. Considering the peak expression time for each diurnally regulated gene, and its corresponding functional assignment, most gene functions display temporal enrichment in the day, often with distinct patterns, such as dawn or midday preferred, indicating that there is a staged procession of biological events undulating with the diurnal cycle. Notably, many gene functions display a bimodal enrichment flanking the midday photosynthetic maximum, with an initial peak in mid-morning followed by another peak during the afternoon/evening. In contrast to leaves, in developing ears as few as 47 gene transcripts are diurnally regulated, and this set of transcripts includes primarily the core oscillators. In developing ears, which are largely shielded from light, the core oscillator therefore is intact with little outward effect on transcription.

  11. Rhythm perception and production predict reading abilities in developmental dyslexia

    Directory of Open Access Journals (Sweden)

    Elena eFlaugnacco

    2014-06-01

    Full Text Available Rhythm organizes events in time and plays a major role in music, but also in the phonology and prosody of a language. Interestingly, children with developmental dyslexia - a learning disability that affects reading acquisition despite normal intelligence and adequate education - have a poor rhythmic perception. It has been suggested that an accurate perception of rhythmical/metrical structure, that requires accurate perception of rise time, may be critical for phonological development and subsequent literacy. This hypothesis is mostly based on results showing a high degree of correlation between phonological awareness and metrical skills, using a very specific metrical task. We present new findings from the analysis of a sample of 48 children with a diagnosis of dyslexia, without comorbidities. These children were assessed with neuropsychological tests, as well as specifically-devised psychoacoustic and musical tasks mostly testing temporal abilities. Associations were tested by multivariate analyses including data mining strategies, correlations and most importantly logistic regressions to understand to what extent the different auditory and musical skills can be a robust predictor of reading and phonological skills. Results show a strong link between several temporal skills and phonological and reading abilities. These findings are discussed in the framework of the neuroscience literature comparing music and language processing, with a particular interest in the links between rhythm processing in music and language.

  12. Tracking social rhythms of the heart: from dataism to art

    Directory of Open Access Journals (Sweden)

    Veera Mustonen

    2013-11-01

    Full Text Available The authors conducted a curiosity-driven study to explore what a vast body of self-tracking data could reveal about the rhythms of everyday life. The authors instructed thirty-six research participants to engage in self-tracking for a week. They measured their physiological stress and recovery 24/7 for this period. In addition to that the participants recorded their subjective experiences of stress and recovery. Using different methods of analysis and interviews, the authors were able to form data sets demonstrating both individual behaviour and interpretations of the data and the collective rhythms of all the participants. Their analysis contrasted the aggregate-level 'big data' of all the participants and the personal-level 'small data'. People’s subjective evaluations of their stress and recovery systematically differed from the physiological measurements. The big data revealed behavioural patterns and causalities that were not recognized at the individual level. The small data, on the other hand, offered rich material for personal interpretations and reflections of the individuals' own lives. To communicate both levels of the data the science project resorted to artistic expressions.

  13. Spontaneous group synchronization of movements and respiratory rhythms.

    Directory of Open Access Journals (Sweden)

    Erwan Codrons

    Full Text Available We tested whether pre-assigned arm movements performed in a group setting spontaneously synchronized and whether synchronization extended to heart and respiratory rhythms. We monitored arm movements, respiration and electrocardiogram at rest and during spontaneous, music and metronome-associated arm-swinging. No directions were given on whether or how the arm swinging were to be synchronized between participants or with the external cues. Synchronization within 3 groups of 10 participants studied collectively was compared with pseudo-synchronization of 3 groups of 10 participants that underwent an identical protocol but in an individual setting. Motor synchronization was found to be higher in the collective groups than in the individuals for the metronome-associated condition. On a repetition of the protocol on the following day, motor synchronization in the collective groups extended to the spontaneous, un-cued condition. Breathing was also more synchronized in the collective groups than in the individuals, particularly at rest and in the music-associated condition. Group synchronization occurs without explicit instructions, and involves both movements and respiratory control rhythms.

  14. An allele of the crm gene blocks cyanobacterial circadian rhythms.

    Science.gov (United States)

    Boyd, Joseph S; Bordowitz, Juliana R; Bree, Anna C; Golden, Susan S

    2013-08-20

    The SasA-RpaA two-component system constitutes a key output pathway of the cyanobacterial Kai circadian oscillator. To date, rhythm of phycobilisome associated (rpaA) is the only gene other than kaiA, kaiB, and kaiC, which encode the oscillator itself, whose mutation causes completely arrhythmic gene expression. Here we report a unique transposon insertion allele in a small ORF located immediately upstream of rpaA in Synechococcus elongatus PCC 7942 termed crm (for circadian rhythmicity modulator), which results in arrhythmic promoter activity but does not affect steady-state levels of RpaA. The crm ORF complements the defect when expressed in trans, but only if it can be translated, suggesting that crm encodes a small protein. The crm1 insertion allele phenotypes are distinct from those of an rpaA null; crm1 mutants are able to grow in a light:dark cycle and have no detectable oscillations of KaiC phosphorylation, whereas low-amplitude KaiC phosphorylation rhythms persist in the absence of RpaA. Levels of phosphorylated RpaA in vivo measured over time are significantly altered compared with WT in the crm1 mutant as well as in the absence of KaiC. Taken together, these results are consistent with the hypothesis that the Crm polypeptide modulates a circadian-specific activity of RpaA.

  15. Circadian rhythm of energy expenditure and oxygen consumption.

    Science.gov (United States)

    Leuck, Marlene; Levandovski, Rosa; Harb, Ana; Quiles, Caroline; Hidalgo, Maria Paz

    2014-02-01

    This study aimed to evaluate the effect of continuous and intermittent methods of enteral nutrition (EN) administration on circadian rhythm. Thirty-four individuals, aged between 52 and 80 years, were fed through a nasoenteric tube. Fifteen individuals received a continuous infusion for 24 hours/d, and 19 received an intermittent infusion in comparable quantities, every 4 hours from 8:00 to 20:00. In each patient, 4 indirect calorimetric measurements were carried out over 24 hours (A: 7:30, B: 10:30, C: 14:30, and D: 21:30) for 3 days. Energy expenditure and oxygen consumption were significantly higher in the intermittent group than in the continuous group (1782 ± 862 vs 1478 ± 817 kcal/24 hours, P = .05; 257 125 vs 212 117 ml/min, P = .048, respectively). The intermittent group had higher levels of energy expenditure and oxygen consumption at all the measured time points compared with the continuous group. energy expenditure and oxygen consumption in both groups were significantly different throughout the day for 3 days. There is circadian rhythm variation of energy expenditure and oxygen consumption with continuous and intermittent infusion for EN. This suggests that only one indirect daily calorimetric measurement is not able to show the patient's true needs. Energy expenditure is higher at night with both food administration methods. Moreover, energy expenditure and oxygen consumption are higher with the intermittent administration method at all times.

  16. Weight Rhythms: Weight Increases during Weekends and Decreases during Weekdays

    Directory of Open Access Journals (Sweden)

    Anna-Leena Orsama

    2014-01-01

    Full Text Available Background/Aims: The week's cycle influences sleep, exercise, and eating habits. An accurate description of weekly weight rhythms has not been reported yet - especially across people who lose weight versus those who maintain or gain weight. Methods: The daily weight in 80 adults (BMI 20.0-33.5 kg/m2; age, 25-62 years was recorded and analysed to determine if a group-level weekly weight fluctuation exists. This was a retrospective study of 4,657 measurements during 15-330 monitoring days. Semi-parametric regression was used to model the rhythm. Results: A pattern of daily weight changes was found (p Conclusion: Weight variations between weekends and weekdays should be considered as normal instead of signs of weight gain. Those who compensate the most are most likely to either lose or maintain weight over time. Long-term habits may make more of a difference than short-term splurges. People prone to weight gain could be counselled about the importance of weekday compensation.

  17. Protecting the Melatonin Rhythm through Circadian Healthy Light Exposure

    Directory of Open Access Journals (Sweden)

    Maria Angeles Bonmati-Carrion

    2014-12-01

    Full Text Available Currently, in developed countries, nights are excessively illuminated (light at night, whereas daytime is mainly spent indoors, and thus people are exposed to much lower light intensities than under natural conditions. In spite of the positive impact of artificial light, we pay a price for the easy access to light during the night: disorganization of our circadian system or chronodisruption (CD, including perturbations in melatonin rhythm. Epidemiological studies show that CD is associated with an increased incidence of diabetes, obesity, heart disease, cognitive and affective impairment, premature aging and some types of cancer. Knowledge of retinal photoreceptors and the discovery of melanopsin in some ganglion cells demonstrate that light intensity, timing and spectrum must be considered to keep the biological clock properly entrained. Importantly, not all wavelengths of light are equally chronodisrupting. Blue light, which is particularly beneficial during the daytime, seems to be more disruptive at night, and induces the strongest melatonin inhibition. Nocturnal blue light exposure is currently increasing, due to the proliferation of energy-efficient lighting (LEDs and electronic devices. Thus, the development of lighting systems that preserve the melatonin rhythm could reduce the health risks induced by chronodisruption. This review addresses the state of the art regarding the crosstalk between light and the circadian system.

  18. Calculating activation energies for temperature compensation in circadian rhythms

    International Nuclear Information System (INIS)

    Bodenstein, C; Heiland, I; Schuster, S

    2011-01-01

    Many biological species possess a circadian clock, which helps them anticipate daily variations in the environment. In the absence of external stimuli, the rhythm persists autonomously with a period of approximately 24 h. However, single pulses of light, nutrients, chemicals or temperature can shift the clock phase. In the case of light- and temperature-cycles, this allows entrainment of the clock to cycles of exactly 24 h. Circadian clocks have the remarkable property of temperature compensation, that is, the period of the circadian rhythm remains relatively constant within a physiological range of temperatures. For several organisms, temperature-regulated processes within the circadian clock have been identified in recent years. However, how these processes contribute to temperature compensation is not fully understood. Here, we theoretically investigate temperature compensation in general oscillatory systems. It is known that every oscillator can be locally temperature compensated around a reference temperature, if reactions are appropriately balanced. A balancing is always possible if the control coefficient with respect to the oscillation period of at least one reaction in the oscillator network is positive. However, for global temperature compensation, the whole physiological temperature range is relevant. Here, we use an approach which leads to an optimization problem subject to the local balancing principle. We use this approach to analyse different circadian clock models proposed in the literature and calculate activation energies that lead to temperature compensation

  19. Familial circadian rhythm disorder in the diurnal primate, Macaca mulatta.

    Directory of Open Access Journals (Sweden)

    Irina V Zhdanova

    Full Text Available In view of the inverse temporal relationship of central clock activity to physiological or behavioral outputs in diurnal and nocturnal species, understanding the mechanisms and physiological consequences of circadian disorders in humans would benefit from studies in a diurnal animal model, phylogenetically close to humans. Here we report the discovery of the first intrinsic circadian disorder in a family of diurnal non-human primates, the rhesus monkey. The disorder is characterized by a combination of delayed sleep phase, relative to light-dark cycle, mutual desynchrony of intrinsic rhythms of activity, food intake and cognitive performance, enhanced nighttime feeding or, in the extreme case, intrinsic asynchrony. The phenotype is associated with normal length of intrinsic circadian period and requires an intact central clock, as demonstrated by an SCN lesion. Entrainment to different photoperiods or melatonin administration does not eliminate internal desynchrony, though melatonin can temporarily reinstate intrinsic activity rhythms in the animal with intrinsic asynchrony. Entrainment to restricted feeding is highly effective in animals with intrinsic or SCN lesion-induced asynchrony. The large isolated family of rhesus macaques harboring the disorder provides a powerful new tool for translational research of regulatory circuits underlying circadian disorders and their effective treatment.

  20. Rhythm and interpersonal synchrony in early social development.

    Science.gov (United States)

    Trainor, Laurel J; Cirelli, Laura

    2015-03-01

    Adults who engage in synchronous movement to music later report liking each other better, remembering more about each other, trusting each other more, and are more likely to cooperate with each other compared to adults who engage in asynchronous movements. Although poor motor coordination limits infants' ability to entrain to a musical beat, they perceive metrical structure in auditory rhythm patterns, their movements are affected by the tempo of music they hear, and if they are bounced by an adult to a rhythm pattern, the manner of this bouncing can affect their auditory interpretation of the meter of that pattern. In this paper, we review studies showing that by 14 months of age, infants who are bounced in synchrony with an adult subsequently show more altruistic behavior toward that adult in the form of handing back objects "accidentally" dropped by the adult compared to infants who are bounced asynchronously with the adult. Furthermore, increased helpfulness is directed at the synchronized bounce partner, but not at a neutral stranger. Interestingly, however, helpfulness does generalize to a "friend" of the synchronized bounce partner. In sum, synchronous movement between infants and adults has a powerful effect on infants' expression of directed prosocial behavior. © 2014 New York Academy of Sciences.

  1. Disruption of Circadian rhythms enhances radiation tolerance in mice

    International Nuclear Information System (INIS)

    Patil, Shrikant L.; Krishna, A.P.; Somashekarappa, H.M.; Patil, Rajashekar K.

    2014-01-01

    Whether an alteration in responses to the radiations depends on the phase of Circadian rhythm, this has been explored previously. The results however have been inconclusive and only survival rate of animals has been considered to represent the effect. Circadian phase has been shown to be critical in many therapeutic procedures. The present study was conducted on control group of mice (12L: 12D), extended day length and night length by imposing 24 hrs of light followed by 24 hrs of darkness, a third group received (8L: 8D) light: day cycles. These regimes were operational for seven days, at the end of seventh day mice from three different groups were exposed to 3 Gy of total body gamma radiation. Survival study, extent of lipid peroxidation and antioxidant status was estimated. Radioresistance was found to be enhanced in mice maintained at 8L: 8D cycle. There was no significant changes observed in mice of time shift group (24L: 24D). The corresponding shift in the acrophase of radioresistance following a sudden time shift supports the effect of disrupted circadian rhythms. (author)

  2. Medical Students Circadian Sleep Rhythms and Academic Performance

    Directory of Open Access Journals (Sweden)

    Isabel Pérez-Olmos

    2006-10-01

    Full Text Available Objective: to evaluate, with a preliminarystudy, the distribution of circadian rhythms, sleepschedule patterns and their relationship withacademic performance on medical students.Methodology: in this descriptive study, a 10 itemoriginal questionnaire about sleep rhythms andacademic performance was applied to medicalstudents from different semesters. Week (classtime and weekend schedules, preferences,daytime somnolence and academic performancewere asked. Three chronotypes (morningness,intermediate and eveningness were definedamong waking-sleeping preference, difficulty tosleep early, exam preparation preference hour and real sleep schedule. The sleep hour deficit perweek night was also calculated. Results: Of the318 medical students that answered the questionnaire,62.6% corresponded to intermediatechronotypes, 8.8% to evening-type and 28.7%to morning-type. Significant difference wasfound among the two chronotype tails (p=0.000,Chi-square 31.13. No correlation was foundbetween academic performance and age, sex,chronotype, week sleep deficit and sleep hours inweek and weekends. A 71.1% of the students slept6 or fewer hours during class time and 78% hada sleep deficit (more frequent in the eveningchronotype. Conclusions: No relation was foundbetween sleep chronotype and academic performance.Students tend to morningness. Fewstudies have been made on equatorial zones orwithout seasons.

  3. F0-based rhythm effects on the perception of local syllable prominence

    DEFF Research Database (Denmark)

    Niebuhr, Oliver

    2009-01-01

    of the global rhythmic context with regard to both the prominence and the F(0) patterns. Two conclusions were drawn on this basis. First, listeners use speech rhythm to predict the perceptual properties of syllables, which is in line with the guide function that speech rhythm is assumed to have in German...

  4. Sleep and Sleep-wake Rhythm in Older Adults with Intellectual Disabilities

    NARCIS (Netherlands)

    E. van de Wouw-Van Dijk (Ellen)

    2013-01-01

    textabstractEveryone who has experienced poor sleep knows how it affects daytime functioning and wellbeing. A good night’s rest and a stable sleep-wake rhythm are therefore very important. The sleep-wake rhythm is regulated by several brain structures. People with an intellectual disability (ID) all

  5. Ultradian activity rhythms in large groups of newly hatched chicks (Gallus gallus domesticus).

    Science.gov (United States)

    Nielsen, B L; Erhard, H W; Friggens, N C; McLeod, J E

    2008-07-01

    A clutch of young chicks housed with a mother hen exhibit ultradian (within day) rhythms of activity corresponding to the brooding cycle of the hen. In the present study clear evidence was found of ultradian activity rhythms in newly hatched domestic chicks housed in groups larger than natural clutch size without a mother hen or any other obvious external time-keeper. No consistent synchrony was found between groups housed in different pens within the same room. The ultradian rhythms disappeared with time and little evidence of group rhythmicity remained by the third night. This disappearance over time suggests that the presence of a mother hen may be pivotal for the long-term maintenance of these rhythms. The ultradian rhythm of the chicks may also play an important role in the initiation of brooding cycles during the behavioural transition of the mother hen from incubation to brooding. Computer simulations of individual activity rhythms were found to reproduce the observations made on a group basis. This was achievable even when individual chick rhythms were modelled as independent of each other, thus no assumptions of social facilitation are necessary to obtain ultradian activity rhythms on a group level.

  6. Indirect bright light improves circadian rest-activity rhythm disturbances in demented patients

    NARCIS (Netherlands)

    van Someren, E. J.; Kessler, A.; Mirmiran, M.; Swaab, D. F.

    1997-01-01

    Light is known to be an important modulator of circadian rhythms. We tested the hypothesis than an enduring increase in the daytime environmental illumination level improves rest-activity rhythm disturbances in demented patients. Actigraphy was performed before, during, and after 4 weeks of

  7. Social memory in the rat: circadian variation and effect of circadian rhythm disruption

    NARCIS (Netherlands)

    Reijmers, L.G.J.E.; Leus, I.E.; Burbach, J.P.H.; Spruijt, B.M.; Ree, van J.M.

    2001-01-01

    Disruption of circadian rhythm can impair long-term passive avoidance memory of rats and mice. The present study investigated whether disruption of circadian rhythm can also impair social memory of male rats. Social memory was assessed using the social discrimination test, in which a short-term

  8. Effect of Melodic Rhythm on Elementary Students' and College Undergraduates' Perceptions of Relative Tempo.

    Science.gov (United States)

    Duke, Robert A.

    1989-01-01

    Uses extant musical examples as stimuli in order to assess the effect of melodic rhythm as a determinant of relative tempo as perceived by college undergraduates and elementary students. Results indicate that subjects responded to the melodic rhythm as well as the beat when making tempo judgments. (LS)

  9. A circadian rhythm orchestrated by histone deacetylase 3 controls hepatic lipid metabolism

    DEFF Research Database (Denmark)

    Feng, Dan; Liu, Tao; Sun, Zheng

    2011-01-01

    Disruption of the circadian clock exacerbates metabolic diseases, including obesity and diabetes. We show that histone deacetylase 3 (HDAC3) recruitment to the genome displays a circadian rhythm in mouse liver. Histone acetylation is inversely related to HDAC3 binding, and this rhythm is lost whe...

  10. The role of stress and accent in the perception of speech rhythm

    NARCIS (Netherlands)

    Grover, C.N.; Terken, J.M.B.

    1995-01-01

    Modelling rhythmic characteristics of speech is expected to contribute to the acceptability of synthetic speech. However, before rules for the control of speech rhythm in synthetic speech can be developed, we need to know which properties of speech give rise to the perception of speech rhythm. An

  11. Hypophysectomy abolishes rhythms in rat thyroid hormones but not in the thyroid clock

    DEFF Research Database (Denmark)

    Fahrenkrug, J; Georg, B; Hannibal, J

    2017-01-01

    The endocrine body rhythms including the hypothalamic-pituitary-thyroid axis seem to be regulated by the circadian timing system, and daily rhythmicity of circulating thyroid-stimulating hormone (TSH) is well established. The circadian rhythms are generated by endogenous clocks in the central bra...

  12. Transcutaneous electrical nerve stimulation (TENS) improves the rest-activity rhythm in midstage Alzheimer's disease

    NARCIS (Netherlands)

    Scherder, E. J.; van Someren, E. J.; Swaab, D. F.

    1999-01-01

    Nightly restlessness in patients with Alzheimer's disease (AD) is probably due to a disorder of circadian rhythms. Transcutaneous electrical nerve stimulation (TENS) was previously reported to increase the strength of coupling of the circadian rest activity rhythm to Zeitgebers in early stage

  13. Circadian rhythm of urinary potassium excretion during treatment with an angiotensin receptor blocker.

    Science.gov (United States)

    Ogiyama, Yoshiaki; Miura, Toshiyuki; Watanabe, Shuichi; Fuwa, Daisuke; Tomonari, Tatsuya; Ota, Keisuke; Kato, Yoko; Ichikawa, Tadashi; Shirasawa, Yuichi; Ito, Akinori; Yoshida, Atsuhiro; Fukuda, Michio; Kimura, Genjiro

    2014-12-01

    We have reported that the circadian rhythm of urinary potassium excretion (U(K)V) is determined by the rhythm of urinary sodium excretion (U(Na)V) in patients with chronic kidney disease (CKD). We also reported that treatment with an angiotensin receptor blocker (ARB) increased the U(Na)V during the daytime, and restored the non-dipper blood pressure (BP) rhythm into a dipper pattern. However, the circadian rhythm of U(K)V during ARB treatment has not been reported. Circadian rhythms of U(Na)V and U(K)V were examined in 44 patients with CKD undergoing treatment with ARB. Whole-day U(Na)V was not altered by ARB whereas whole-day U(K)V decreased. Even during the ARB treatment, the significant relationship persisted between the night/day ratios of U(Na)V and U(K)V (r=0.56, pcircadian rhythm of U(K)V was determined by the rhythm of UNaV even during ARB treatment. Changes in the circadian U(K)V rhythm were not determined by aldosterone but by U(Na)V. © The Author(s) 2013.

  14. Alterations in the circadian rhythm of salivary melatonin begin during middle-age

    NARCIS (Netherlands)

    Zhou, Jiang-Ning; Liu, Rong-Yu; van Heerikhuize, Joop; Hofman, Michel A.; Swaab, Dick F.

    2003-01-01

    To investigate whether free melatonin may be better suited to reveal age-related changes, we studied the circadian rhythm alterations in saliva melatonin levels during aging. Special attention was paid to the question as to how the free melatonin rhythms change in aging and when such changes take

  15. The aesthetic value of the golden ratio and rhythm of the photographs

    Directory of Open Access Journals (Sweden)

    Ivan Budimir

    2015-05-01

    Full Text Available The study analyzes the aesthetic value of rhythm of the photos as opposed to the form in which the rhythm is subjected. With the method of experimental aesthetics, the visual aesthetics experiment is conducted in which the tested quality of the different forms of proportional rhythm due to the shape and length of the interval as a part of the rhythmic matrix. The experimental part consisted of an assessment of visual quality of the 5 photos containing different variations of proportional rate. On all the photographs the rhythm is constituted of cigarettes situated on the surface of the old concrete. Spacing between cigarettes and interval length is successively reduced to accurately defined proportions. In one photograph, the relations between the neighboring intervals are in line with the ratio of the golden section. The experiment involved 32 subjects who had the task of assessing the level of the aesthetic qualities of rhythm on the Likert scale from 1 to 5 where the grades cannot be repeated. Measurement of the quality of a particular form of rhythm is defined as the arithmetic mean score of all respondents. The highest mean is given to the test image with uniform rhythm when the second place is reserved for a photograph whose rhythm is aligned with the golden section. Conducted analysis of repeated measures ANOVA showed that the obtained arithmetic means differ significantly (F = 3.430, p = 0.011 with a significance level of p 0.05.

  16. Two Coupled Oscillators : Simulations of the Circadian Pacemaker in Mammalian Activity Rhythms

    NARCIS (Netherlands)

    Daan, Serge; Berde, Charles

    1978-01-01

    In the activity rhythms of captive small mammals a variety of features, most notably “splitting”, sugges that two coupled oscillators may constitute the pacemaker system which underlies the rhythms. A proposed phenomenological model is developed and expanded here using an explicit quantitative

  17. Tests of the disrupted behavioral rhythms hypothesis for accelerated summer weight gain

    Science.gov (United States)

    The school-summer paradigm offers an opportunity to explore school-summer differences in children's behavioral rhythms and their association with seasonal changes in BMI. In the absence of the environmental demands and cues associated with the school year, children's behavioral rhythms (e.g., sleep...

  18. Rhythm Perception and Its Role in Perception and Learning of Dysrhythmic Speech.

    Science.gov (United States)

    Borrie, Stephanie A; Lansford, Kaitlin L; Barrett, Tyson S

    2017-03-01

    The perception of rhythm cues plays an important role in recognizing spoken language, especially in adverse listening conditions. Indeed, this has been shown to hold true even when the rhythm cues themselves are dysrhythmic. This study investigates whether expertise in rhythm perception provides a processing advantage for perception (initial intelligibility) and learning (intelligibility improvement) of naturally dysrhythmic speech, dysarthria. Fifty young adults with typical hearing participated in 3 key tests, including a rhythm perception test, a receptive vocabulary test, and a speech perception and learning test, with standard pretest, familiarization, and posttest phases. Initial intelligibility scores were calculated as the proportion of correct pretest words, while intelligibility improvement scores were calculated by subtracting this proportion from the proportion of correct posttest words. Rhythm perception scores predicted intelligibility improvement scores but not initial intelligibility. On the other hand, receptive vocabulary scores predicted initial intelligibility scores but not intelligibility improvement. Expertise in rhythm perception appears to provide an advantage for processing dysrhythmic speech, but a familiarization experience is required for the advantage to be realized. Findings are discussed in relation to the role of rhythm in speech processing and shed light on processing models that consider the consequence of rhythm abnormalities in dysarthria.

  19. Interactions between thalamic and cortical rhythms during semantic memory recall in human

    Science.gov (United States)

    Slotnick, Scott D.; Moo, Lauren R.; Kraut, Michael A.; Lesser, Ronald P.; Hart, John, Jr.

    2002-04-01

    Human scalp electroencephalographic rhythms, indicative of cortical population synchrony, have long been posited to reflect cognitive processing. Although numerous studies employing simultaneous thalamic and cortical electrode recording in nonhuman animals have explored the role of the thalamus in the modulation of cortical rhythms, direct evidence for thalamocortical modulation in human has not, to our knowledge, been obtained. We simultaneously recorded from thalamic and scalp electrodes in one human during performance of a cognitive task and found a spatially widespread, phase-locked, low-frequency rhythm (7-8 Hz) power decrease at thalamus and scalp during semantic memory recall. This low-frequency rhythm power decrease was followed by a spatially specific, phase-locked, fast-rhythm (21-34 Hz) power increase at thalamus and occipital scalp. Such a pattern of thalamocortical activity reflects a plausible neural mechanism underlying semantic memory recall that may underlie other cognitive processes as well.

  20. Heart rhythm analysis using ECG recorded with a novel sternum based patch technology

    DEFF Research Database (Denmark)

    Saadi, Dorthe Bodholt; Fauerskov, Inge; Osmanagic, Armin

    2013-01-01

    , reliable long-term ECG recordings. The device is designed for high compliance and low patient burden. This novel patch technology is CE approved for ambulatory ECG recording of two ECG channels on the sternum. This paper describes a clinical pilot study regarding the usefulness of these ECG signals...... for heart rhythm analysis. A clinical technician with experience in ECG interpretation selected 200 noise-free 7 seconds ECG segments from 25 different patients. These 200 ECG segments were evaluated by two medical doctors according to their usefulness for heart rhythm analysis. The first doctor considered...... 98.5% of the segments useful for rhythm analysis, whereas the second doctor considered 99.5% of the segments useful for rhythm analysis. The conclusion of this pilot study indicates that two channel ECG recorded on the sternum is useful for rhythm analysis and could be used as input to diagnosis...

  1. Acquisition of speech rhythm in a second language by learners with rhythmically different native languages.

    Science.gov (United States)

    Ordin, Mikhail; Polyanskaya, Leona

    2015-08-01

    The development of speech rhythm in second language (L2) acquisition was investigated. Speech rhythm was defined as durational variability that can be captured by the interval-based rhythm metrics. These metrics were used to examine the differences in durational variability between proficiency levels in L2 English spoken by French and German learners. The results reveal that durational variability increased as L2 acquisition progressed in both groups of learners. This indicates that speech rhythm in L2 English develops from more syllable-timed toward more stress-timed patterns irrespective of whether the native language of the learner is rhythmically similar to or different from the target language. Although both groups showed similar development of speech rhythm in L2 acquisition, there were also differences: German learners achieved a degree of durational variability typical of the target language, while French learners exhibited lower variability than native British speakers, even at an advanced proficiency level.

  2. V3 spinal neurons establish a robust and balanced locomotor rhythm during walking.

    Science.gov (United States)

    Zhang, Ying; Narayan, Sujatha; Geiman, Eric; Lanuza, Guillermo M; Velasquez, Tomoko; Shanks, Bayle; Akay, Turgay; Dyck, Jason; Pearson, Keir; Gosgnach, Simon; Fan, Chen-Ming; Goulding, Martyn

    2008-10-09

    A robust and well-organized rhythm is a key feature of many neuronal networks, including those that regulate essential behaviors such as circadian rhythmogenesis, breathing, and locomotion. Here we show that excitatory V3-derived neurons are necessary for a robust and organized locomotor rhythm during walking. When V3-mediated neurotransmission is selectively blocked by the expression of the tetanus toxin light chain subunit (TeNT), the regularity and robustness of the locomotor rhythm is severely perturbed. A similar degeneration in the locomotor rhythm occurs when the excitability of V3-derived neurons is reduced acutely by ligand-induced activation of the allatostatin receptor. The V3-derived neurons additionally function to balance the locomotor output between both halves of the spinal cord, thereby ensuring a symmetrical pattern of locomotor activity during walking. We propose that the V3 neurons establish a regular and balanced motor rhythm by distributing excitatory drive between both halves of the spinal cord.

  3. Spontaneous internal desynchronization of locomotor activity and body temperature rhythms from plasma melatonin rhythm in rats exposed to constant dim light

    Directory of Open Access Journals (Sweden)

    Bullock Nicole M

    2006-04-01

    Full Text Available Abstract Background We have recently reported that spontaneous internal desynchronization between the locomotor activity rhythm and the melatonin rhythm may occur in rats (30% of tested animals when they are maintained in constant dim red light (LLdim for 60 days. Previous work has also shown that melatonin plays an important role in the modulation of the circadian rhythms of running wheel activity (Rw and body temperature (Tb. The aim of the present study was to investigate the effect that desynchronization of the melatonin rhythm may have on the coupling and expression of circadian rhythms in Rw and Tb. Methods Rats were maintained in a temperature controlled (23–24°C ventilated lightproof room under LLdim (red dim light 1 μW/cm2 [5 Lux], lower wavelength cutoff at 640 nm. Animals were individually housed in cages equipped with a running wheel and a magnetic sensor system to detect wheel rotation; Tb was monitored by telemetry. Tb and Rw data were recorded in 5-min bins and saved on disk. For each animal, we determined the mesor and the amplitude of the Rw and Tb rhythm using waveform analysis on 7-day segments of the data. After sixty days of LLdim exposure, blood samples (80–100 μM were collected every 4 hours over a 24-hrs period from the tail artery, and serum melatonin levels were measured by radioimmunoassay. Results Twenty-one animals showed clear circadian rhythms Rw and Tb, whereas one animal was arrhythmic. Rw and Tb rhythms were always strictly associated and we did not observe desynchronization between these two rhythms. Plasma melatonin levels showed marked variations among individuals in the peak levels and in the night-to-day ratio. In six rats, the night-to-day ratio was less than 2, whereas in the rat that showed arrhythmicity in Rw and Tb melatonin levels were high and rhythmic with a large night-to-day ratio. In seven animals, serum melatonin levels peaked during the subjective day (from CT0 to CT8, thus suggesting

  4. Wheel-running activity modulates circadian organization and the daily rhythm of eating behavior

    Science.gov (United States)

    Pendergast, Julie S.; Branecky, Katrina L.; Huang, Roya; Niswender, Kevin D.; Yamazaki, Shin

    2014-01-01

    Consumption of high-fat diet acutely alters the daily rhythm of eating behavior and circadian organization (the phase relationship between oscillators in central and peripheral tissues) in mice. Voluntary wheel-running activity counteracts the obesogenic effects of high-fat diet and also modulates circadian rhythms in mice. In this study, we sought to determine whether voluntary wheel-running activity could prevent the proximate effects of high-fat diet consumption on circadian organization and behavioral rhythms in mice. Mice were housed with locked or freely rotating running wheels and fed chow or high-fat diet for 1 week and rhythms of locomotor activity, eating behavior, and molecular timekeeping (PERIOD2::LUCIFERASE luminescence rhythms) in ex vivo tissues were measured. Wheel-running activity delayed the phase of the liver rhythm by 4 h in both chow- and high-fat diet-fed mice. The delayed liver phase was specific to wheel-running activity since an enriched environment without the running wheel did not alter the phase of the liver rhythm. In addition, wheel-running activity modulated the effect of high-fat diet consumption on the daily rhythm of eating behavior. While high-fat diet consumption caused eating events to be more evenly dispersed across the 24 h-day in both locked-wheel and wheel-running mice, the effect of high-fat diet was much less pronounced in wheel-running mice. Together these data demonstrate that wheel-running activity is a salient factor that modulates liver phase and eating behavior rhythms in both chow- and high-fat-diet fed mice. Wheel-running activity in mice is both a source of exercise and a self-motivating, rewarding behavior. Understanding the putative reward-related mechanisms whereby wheel-running activity alters circadian rhythms could have implications for human obesity since palatable food and exercise may modulate similar reward circuits. PMID:24624109

  5. THEORY AND PRACTICE OF RHYTHM IN THE PROFESSIONAL TRAINING SYSTEM FOR ATHLETES AND TEACHING STAFF

    Directory of Open Access Journals (Sweden)

    Olga Aftimichuk

    2015-09-01

    Full Text Available Background . Rhythm is important for the implementation of all processes as in nature and in living organisms. It organizes motor human activity making it more productive and rational. On teaching working and sports motions the process of the impellent work correct rhythm assimilation plays an important role because it determines the movement performance optimum that is shown in its automation process reduction. As a result, man’s physical strength and nervous energy are saved. Rhythm category acquires a special status for the physical training specialist. All his activity including the motor component depends on the rhythm. The aim of the research is to study the physiology of rhythm and justify the more efficient training process for future teachers and coaches. Methods . The following theoretical research methods were used: the abstract and axiomatic methods, analysis and synthesis, induction and deduction, idealization, comparison and generalization. Results. As a result of study of materials from the natural sciences, numerology, psychology, music, cybernetics, synergetic, physiology, was found that the change of different states, as in nature and in living organisms, is an undulating rhythmic character. Physiological basis of the same rhythm is dynamic change excitation and inhibition processes occurring in the central nervous system. In this paper features of rhythm were identified. To accelerate the assimilation of motor action rational rhythm it is necessary to develop a sense of rhythm which is successfully formed in during the musical-motor activities. Conclusions. For today the study of the rhythm phenomenon in professional preparation on physical education and sport, in our opinion, requires the further study. Adding exercises involving certain motor skills elements similar in rhythmic structure with professional and technical actions to the coaches and teachers education and the competitive technology formation should be

  6. Chaos control applied to cardiac rhythms represented by ECG signals

    International Nuclear Information System (INIS)

    Borem Ferreira, Bianca; Amorim Savi, Marcelo; Souza de Paula, Aline

    2014-01-01

    The control of irregular or chaotic heartbeats is a key issue in cardiology. In this regard, chaos control techniques represent a good alternative since they suggest treatments different from those traditionally used. This paper deals with the application of the extended time-delayed feedback control method to stabilize pathological chaotic heart rhythms. Electrocardiogram (ECG) signals are employed to represent the cardiovascular behavior. A mathematical model is employed to generate ECG signals using three modified Van der Pol oscillators connected with time delay couplings. This model provides results that qualitatively capture the general behavior of the heart. Controlled ECG signals show the ability of the strategy either to control or to suppress the chaotic heart dynamics generating less-critical behaviors. (paper)

  7. Differentiation of classical music requires little learning but rhythm.

    Science.gov (United States)

    Dalla Bella, Simone; Peretz, Isabelle

    2005-06-01

    Detecting distinctions between the styles of classical music (e.g. Baroque and Romantic) is often viewed as the privilege of musicians. However, this elite perspective underestimates the abilities of non-musicians. We report that Western musicians and non-musicians, and non-Westerners (i.e. Chinese participants) rated pairs of excerpts presented auditorily as more similar as their compositional styles were closer in history. Moreover, the styles were considered by all participants as more different when presented in historical order, the older style preceding the more recent style (e.g. Baroque followed by Romantic), than the reverse (e.g. Romantic followed by Baroque). This historical distance effect appears related to rhythm (or temporal variability).

  8. Wet cupping therapy restores sympathovagal imbalances in cardiac rhythm.

    Science.gov (United States)

    Arslan, Müzeyyen; Yeşilçam, Nesibe; Aydin, Duygu; Yüksel, Ramazan; Dane, Senol

    2014-04-01

    A recent study showed that cupping had therapeutic effects in rats with myocardial infarction and cardiac arrhythmias. The current studyaimed to investigate the possible useful effects of cupping therapy on cardiac rhythm in terms of heart rate variability (HRV). Forty healthy participants were included. Classic wet cupping therapy was applied on five points of the back. Recording electrocardiography (to determine HRV) was applied 1 hour before and 1 hour after cupping therapy. All HRV parameters increased after cupping therapy compared with before cupping therapy in healthy persons. These results indicate for the first time in humans that cupping might be cardioprotective. In this study, cupping therapy restored sympathovagal imbalances by stimulating the peripheral nervous system.

  9. SLEEP AND CIRCADIAN RHYTHM DISORDERS IN PARKINSON'S DISEASE.

    Science.gov (United States)

    Gros, Priti; Videnovic, Aleksandar

    2017-09-01

    Sleep disorders are among the most challenging non-motor features of Parkinson's disease (PD) and significantly affect quality of life. Research in this field has gained recent interest among clinicians and scientists and is rapidly evolving. This review is dedicated to sleep and circadian dysfunction associated with PD. Most primary sleep disorders may co-exist with PD; majority of these disorders have unique features when expressed in the PD population. We discuss the specific considerations related to the common sleep problems in Parkinson's disease including insomnia, rapid eye movement sleep behavior disorder, restless legs syndrome, sleep disordered breathing, excessive daytime sleepiness and circadian rhythm disorders. Within each of these sleep disorders, we present updated definitions, epidemiology, etiology, diagnosis, clinical implications and management. Furthermore, areas of potential interest for further research are outlined.

  10. Circadian Rhythm Disturbances in Patients with Alzheimer's Disease: A Review

    Directory of Open Access Journals (Sweden)

    Dawit A. Weldemichael

    2010-01-01

    Full Text Available Circadian Rhythm Disturbances (CRDs affect as many as a quarter of Alzheimer's disease (AD patients during some stage of their illness. Alterations in the suprachiasmatic nucleus and melatonin secretion are the major factors linked with the cause of CRDs. As a result, the normal physiology of sleep, the biological clock, and core body temperature are affected. This paper systematically discusses some of the causative factors, typical symptoms, and treatment options for CRDs in patients with AD. This paper also emphasizes the implementation of behavioral and environmental therapies before embarking on medications to treat CRDs. Pharmacotherapeutic options are summarized to provide symptomatic benefits for the patient and relieve stress on their families and professional care providers. As of today, there are few studies relative to CRDs in AD. Large randomized trials are warranted to evaluate the effects of treatments such as bright light therapy and engaging activities in the reduction of CRDs in AD patients.

  11. Electromagnetic Interference in Implantable Rhythm Devices - The Indian Scenario

    Directory of Open Access Journals (Sweden)

    Johnson Francis

    2002-07-01

    Full Text Available Implantable rhythm device (IRD is the generic name for the group of implantable devices used for diagnosis and treatment of cardiac arrhythmias. Devices in this category include cardiac pacemakers, implantable cardioverter defibrillators and implantable loop recorders. Since these devices have complex microelectronic circuitry and use electromagnetic waves for communication, they are susceptible to interference from extraneous sources of electromagnetic radiation and magnetic energy. Electromagnetic interference (EMI is generally not a major problem outside of the hospital environment. The most important interactions occur when a patient is subjected to medical procedures such as magnetic resonance imaging (MRI, electrocautery and radiation therapy. Two articles in this issue of the journal discusses various aspects of EMI on IRD1,2 . Together these articles provide a good review of the various sources of EMI and their interaction with IRD for the treating physician.

  12. Biological rhythms for rehabilitation of radiation damage of population

    International Nuclear Information System (INIS)

    Goncharova, T.G.; Vasil'eva, G.S.; Efimov, M.L.

    1999-01-01

    Considerable disturbances in biological eurhythmycal structure of redoracu were discovered for people living in Borodulikha area of the Semipalatinsk test site. The deep desynchronise may result in a development of the cardiovascular, bronco-pulmonary, endocrine, oncologic, neuro psychic diseases. A method to correct the biological eurhythmycal structure was developed. Homeopathic doses of melatonin ('rhythm driver' managing the most regenerating and immune systems) and uthynol (promoting production of dehydroepiandrosterone of maternal prehormone of 27 hormones) were used to provide the general correction. The endocrine diseases are not practically subjected to the homeopathic correction. The sub correction was sometimes carried out after 5 months. The developed methods of rehabilitation of the radiation damages are unique, since they allow performing the homeopathic correction using the acupuncture monitoring

  13. Synesthesia and rhythm. The road to absolute cinema

    Directory of Open Access Journals (Sweden)

    Ricardo Roncero Palomar

    2017-05-01

    Full Text Available Absolute cinema, developed during the historical avant-garde, con-tinued with a long artistic tradition that linked musical with visual experience. Due to cinema as médium of expression, this filmmakers were able to work with the moving image to develop concepts such as rhythm, also with more complex figures than the colored spots that other devices could create at those time. This study starts with the published texts in 1704 by Newton about color, and provides an overview of those artistic highlights that link image and sound, and which creates the origins of absolute cinema. The connections and equivalences between the visual and sound experiences used by these filmmakers are also studied in order to know if there was a continuous line with the origins of these studies or if there was a rupture and other later investigations were able to have more repercussion in their works.

  14. Cadências escolares, ritmos docentes School cadences, teaching rhythms

    Directory of Open Access Journals (Sweden)

    Inês Assunção de Castro Teixeira

    1999-07-01

    Full Text Available O artigo analisa alguns dos eixos que estruturam os ritmos cotidianos dos professores, próprios às temporalidades da vida social na escola. Parte do pressuposto de que o tempo é uma "categoria do pensamento lógico", originada no ritmo da vida social (Dukheim, e que essa rítmica é uma "modalidade concreta do tempo social" (Lefebvre e Régulier. O estudo é parte de uma pesquisa que busca tematizar a experiência do tempo de sujeitos que se encontram na condição de professores - docentes de quinta à oitava séries do ensino fundamental e do ensino médio -, levando em conta seus vínculos com a construção de identidades docentes. O texto se desenvolve em torno de três eixos: as cadências das interações entre educandos e educadores, os ritmos dos calendários e os compassos dos horários escolares. Conclui-se que os ritmos docentes, embora circunscritos à rítmica da vida moderna, têm particularidades associadas às cadências da escola, aos processos pedagógicos e àqueles relacionados à formação humana. Trata-se, pois, de analisar a polirritmia dos tempos da escola em sua complexidade e peculiaridades, de forma a se compreenderem as modulações e significações da experiência do tempo na condição de professor, vivência constitutiva das identidades docentes.This paper analyzes some of the concepts peculiar to the temporality of the school social life that structure the everyday rhythm of teachers. It assumes that time is a "category of logical thinking" originated in the rhythm of social life (Durkheim, and that such rhythmic character is a "concrete modality of social time" (Lefebvre and Régulier. This study is part of a research that seeks to discuss the experience of time for teachers of the 5th to 8th grades of the Primary Education and of the Secondary Education, taking into account the teachers’ links with the construction of their own teaching identities. The text is developed around three themes: the cadences

  15. Сircadian rhythm and metabolic effects of melatonin

    Directory of Open Access Journals (Sweden)

    Denis Igorevich Burchakov

    2015-02-01

    Full Text Available Sleep is a highly important process, required for normal organ and system function. Researchers assume, that during sleep brain shifts to internal body signals. Therefore, any sleep disturbance will disrupt health. Industrial and post-industrial society links high stress level and sleep problems. Excess light stimulation in living space, including bedroom, disorganize circadian rhythm of melatonin. Besides regulation this hormone has antioxidant and adaptogen functions. From psychological standpoint the same high-stress social context depletes the adaptation resources. To normalize sleep function we can utilize both sleep hygiene measures and modern pharmacotherapy. There are melatonin-based drugs, which help to restore sleep-wake cycle, augment adaptive capability and in some cases empower the existing treatment for specific somatic maladies. From a clinical and chronobiological standpoint melatonin is useful in broad spectrum of disorders.

  16. Radiobiological arguments for and clinical possibilities of unconventional fractionating rhythms

    International Nuclear Information System (INIS)

    Herrmann, T.; Voigtmann, L.

    1986-01-01

    Radiobiological considerations are presented using unconventional fractionating rhythms. The aim of this method is to enlarge the therapeutic dimensions between maximum tumor destruction and most careful treatment of late responding cell systems. These late responding tissues show a very similar dose-time reaction, probably by reason of a causal injury on cells of the capillary endothelium. In linear-quadratic models for the estimation of the parameters of the number of fractions and total treatment period it becomes evident that a careful treatment of late responding tissue can be attained by reduction of the single dose per fraction. Because with partition of a total dose in several fractions at daily irradiation a longer repopulation period is available also for the tumor irradiations are presented, done repeatedly during the day. Accelerated fractionation (same fractionating number in reduced treatment period) are contrasted to hyperfractionation (increased fractionating number within the same total treatment period) and possibilities in application are suggested. (author)

  17. Circadian blood pressure rhythm in normotensive offspring of hypertensive parents.

    Science.gov (United States)

    Toker, Rabia Tutuncu; Yildirim, Ali; Demir, Tevfik; Ucar, Birsen; Kilic, Zubeyir

    2015-01-01

    The aim of this study was to explore the circadian blood pressure (BP) rhythm using ambulatory BP monitoring (ABPM) in normotensive children with a family history of essential hypertension. Group 1 consisted of children with hypertensive mothers and/or fathers (n = 20), Group 2 consisted of children with hypertensive grandparents (n = 20), and Group 3 consisted of children with normotensive parents (n = 20). All participating children underwent a 24-h ABPM and echocardiography. Significantly higher systolic burden was found in children with hypertensive parents (p children with a family history of hypertension, a positive correlation between nocturnal systolic BP and LVMI was found, and increasing nocturnal BP values were associated with increasing LVMI (p children with a family history of hypertension, target-organ damage may precede the clinical detection of hypertension, and in those with a nocturnal non-dipper status, a more marked effect on LVMI may occur.

  18. Circadian rhythms in sports performance--an update.

    Science.gov (United States)

    Drust, B; Waterhouse, J; Atkinson, G; Edwards, B; Reilly, T

    2005-01-01

    We discuss current knowledge on the description, impact, and underlying causes of circadian rhythmicity in sports performance. We argue that there is a wealth of information from both applied and experimental work, which, when considered together, suggests that sports performance is affected by time of day in normal entrained conditions and that the variation has at least some input from endogenous mechanisms. Nevertheless, precise information on the relative importance of endogenous and exogenous factors is lacking. No single study can answer both the applied and basic research questions that are relevant to this topic, but an appropriate mixture of real-world research on rhythm disturbances and tightly controlled experiments involving forced desynchronization protocols is needed. Important issues, which should be considered by any chronobiologist interested in sports and exercise, include how representative the study sample and the selected performance tests are, test-retest reliability, as well as overall design of the experiment.

  19. Human autonomic rhythms: vagal cardiac mechanisms in tetraplegic subjects

    Science.gov (United States)

    Koh, J.; Brown, T. E.; Beightol, L. A.; Ha, C. Y.; Eckberg, D. L.

    1994-01-01

    1. We studied eight young men (age range: 20-37 years) with chronic, clinically complete high cervical spinal cord injuries and ten age-matched healthy men to determine how interruption of connections between the central nervous system and spinal sympathetic motoneurones affects autonomic cardiovascular control. 2. Baseline diastolic pressures and R-R intervals (heart periods) were similar in the two groups. Slopes of R-R interval responses to brief neck pressure changes were significantly lower in tetraplegic than in healthy subjects, but slopes of R-R interval responses to steady-state arterial pressure reductions and increases were comparable. Plasma noradrenaline levels did not change significantly during steady-state arterial pressure reductions in tetraplegic patients, but rose sharply in healthy subjects. The range of arterial pressure and R-R interval responses to vasoactive drugs (nitroprusside and phenylephrine) was significantly greater in tetraplegic than healthy subjects. 3. Resting R-R interval spectral power at respiratory and low frequencies was similar in the two groups. During infusions of vasoactive drugs, low-frequency R-R interval spectral power was directly proportional to arterial pressure in tetraplegic patients, but was unrelated to arterial pressure in healthy subjects. Vagolytic doses of atropine nearly abolished both low- and respiratory-frequency R-R interval spectral power in both groups. 4. Our conclusions are as follows. First, since tetraplegic patients have significant levels of low-frequency arterial pressure and R-R interval spectral power, human Mayer arterial pressure waves may result from mechanisms that do not involve stimulation of spinal sympathetic motoneurones by brainstem neurones. Second, since in tetraplegic patients, low-frequency R-R interval spectral power is proportional to arterial pressure, it is likely to be mediated by a baroreflex mechanism. Third, since low-frequency R-R interval rhythms were nearly abolished

  20. Effects of atomoxetine on heart rhythm in children and adolescents.

    Science.gov (United States)

    Tanidir, Ibrahim Cansaran; Tanidir, Canan; Ozturk, Erkut; Bahali, Kayhan; Gunes, Hatice; Ergul, Yakup; Uneri, Ozden Sukran; Akdeniz, Celal; Tuzcu, Volkan

    2015-12-01

    The aim of this study was to examine the effects of atomoxetine on heart rhythm using 12-lead electrocardiography (ECG) and 24 h Holter monitoring. Children and adolescents who were diagnosed with attention deficit-hyperactivity disorder according to DSM-IV-TR were referred to a pediatric cardiology clinic for cardiologic examination before and after 4 or 5 weeks of atomoxetine treatment. Cardiac examination, complete blood count, biochemistry, thyroid function tests, 12-lead ECG and 24 h Holter monitoring were performed routinely in all patients. Each subject underwent 24 h Holter ECG monitoring before atomoxetine was started and after 4 or 5 weeks of effective dose atomoxetine treatment. Forty-one patients were included in this prospective study. No statistically significant change was found in QT, QTc or QT interval dispersion or blood pressure before and after 4 or 5 weeks of atomoxetine treatment. There was a statistically significant increase in heart rate (both during the day and at night) and QRS duration, and a statistically significant decrease in P wave dispersion. Three patients had rhythm disturbances. All of these three patients were asymptomatic and none of these arrhythmias reached clinical significance. Atomoxetine did not cause significant changes in ECG or Holter variables. In two patients, who had undiagnosed subclinical extrasystoles, extra beats were increased after 4th week of treatment, but still remained clinically insignificant. Before and after atomoxetine treatment, listening to the heart sounds for a longer time, may help clinicians to notice an extra beat. If an extra beat is identified then 24 Holter monitoring is recommended. © 2015 Japan Pediatric Society.

  1. The impact of instrument-specific musical training on rhythm perception and production

    Directory of Open Access Journals (Sweden)

    Tomas Edward Matthews

    2016-02-01

    Full Text Available Various studies have shown that musical training can improve rhythmic perception and production. These findings tell us that music training can result in rhythm processing advantages but they do not tell us whether practicing a particular instrument could lead to specific effects on rhythm perception or production. The current study used a battery of four rhythm perception and production tasks that were designed to test both higher- and lower-level aspects of rhythm processing. Four groups of musicians (drummers, singers, pianists, string players and a control group of non-musicians were tested. Within-task differences in performance showed that factors such as meter, metrical complexity, tempo and beat phase significantly affected the ability to perceive and synchronize taps to a rhythm or beat. Musicians showed better performance on all rhythm tasks compared to non-musicians. Interestingly, our results revealed no significant differences between musician groups for the vast majority of task measures. This is despite the fact that all musicians were selected to have the majority of their training on the target instrument, had on average more than ten years of experience on their instrument, and were currently practicing. These results suggest that general musical experience is more important than specialized musical experience with regards to perception and production of rhythms.

  2. UVA-induced reset of hydroxyl radical ultradian rhythm improves temporal lipid production in Chlorella vulgaris.

    Science.gov (United States)

    Balan, Ranjini; Suraishkumar, G K

    2014-01-01

    We report for the first time that the endogenous, pseudo-steady-state, specific intracellular levels of the hydroxyl radical (si-OH) oscillate in an ultradian fashion (model system: the microalga, Chlorella vulgaris), and also characterize the various rhythm parameters. The ultradian rhythm in the endogenous levels of the si-OH occurred with an approximately 6 h period in the daily cycle of light and darkness. Further, we expected that the rhythm reset to a shorter period could rapidly switch the cellular redox states that could favor lipid accumulation. We reset the endogenous rhythm through entrainment with UVA radiation, and generated two new ultradian rhythms with periods of approximately 2.97 h and 3.8 h in the light phase and dark phase, respectively. The reset increased the window of maximum lipid accumulation from 6 h to 12 h concomitant with the onset of the ultradian rhythms. Further, the saturated fatty acid content increased approximately to 80% of total lipid content, corresponding to the peak maxima of the hydroxyl radical levels in the reset rhythm. © 2014 American Institute of Chemical Engineers.

  3. Effect of age, gender and exercise on salivary dehydroepiandrosterone circadian rhythm profile in human volunteers.

    Science.gov (United States)

    Al-Turk, Walid; Al-Dujaili, Emad A S

    2016-02-01

    There has been a lot of effort by scientists to elucidate the multi functions of the naturally occurring hormone, dehydroepiandrosterone (DHEA). However, to plan research experiments optimally, it is important first to characterize the diurnal rhythm in healthy individuals. The aim of this research was to investigate the daily circadian rhythms of DHEA among the 2 genders, and the effect of age and exercise on salivary DHEA circadian rhythms. Volunteers (20-39 and 40-60 years) were recruited for 2 studies investigating the salivary DHEA circadian rhythm. The first study looked at the effect of gender and age on DHEA levels on 2 non-consecutive days, and the second study explored the effect of exercise on DHEA circadian rhythm in males. DHEA levels were estimated by a sensitive and specific ELISA method. The results showed a clear daily circadian rhythm in salivary DHEA in all participants groups, however the profile was flatter in the older female group. There was a significant difference between age and gender groups particularly at 8.00 h. In young males DHEA reduced from 541.1 ± 101.3 (mean ± sd) at 8.00 h to 198.9 ± 90.7 pg/mL at 18.00 h; pcircadian rhythm in salivary DHEA in all participants was observed, but the profile was flatter in the older groups. Copyright © 2016. Published by Elsevier Inc.

  4. Electrochemical Detection of Circadian Redox Rhythm in Cyanobacterial Cells via Extracellular Electron Transfer.

    Science.gov (United States)

    Nishio, Koichi; Pornpitra, Tunanunkul; Izawa, Seiichiro; Nishiwaki-Ohkawa, Taeko; Kato, Souichiro; Hashimoto, Kazuhito; Nakanishi, Shuji

    2015-06-01

    Recent research on cellular circadian rhythms suggests that the coupling of transcription-translation feedback loops and intracellular redox oscillations is essential for robust circadian timekeeping. For clarification of the molecular mechanism underlying the circadian rhythm, methods that allow for the dynamic and simultaneous detection of transcription/translation and redox oscillations in living cells are needed. Herein, we report that the cyanobacterial circadian redox rhythm can be electrochemically detected based on extracellular electron transfer (EET), a process in which intracellular electrons are exchanged with an extracellular electrode. As the EET-based method is non-destructive, concurrent detection with transcription/translation rhythm using bioluminescent reporter strains becomes possible. An EET pathway that electrochemically connected the intracellular region of cyanobacterial cells with an extracellular electrode was constructed via a newly synthesized electron mediator with cell membrane permeability. In the presence of the mediator, the open circuit potential of the culture medium exhibited temperature-compensated rhythm with approximately 24 h periodicity. Importantly, such circadian rhythm of the open circuit potential was not observed in the absence of the electron mediator, indicating that the EET process conveys the dynamic information regarding the intracellular redox state to the extracellular electrode. These findings represent the first direct demonstration of the intracellular circadian redox rhythm of cyanobacterial cells. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  5. [Effects of acupuncture on circadian rhythm of blood pressure in patients with essential hypertension].

    Science.gov (United States)

    Lei, Yun; Jin, Jiu; Ban, Haipeng; Du, Yuzheng

    2017-11-12

    To observe the effects of acupuncture combined with medication on circadian rhythm of blood pressure in patients with essential hypertension. Sixty-four patients of essential hypertension were randomly divided into an observation group and a control group, 32 cases in each group. All the patients maintained original treatment (taking antihypertensive medication); the patients in the observation group were treated with acupuncture method of " Huoxue Sanfeng , Shugan Jianpi ", once a day, five times per week, for totally 6 weeks (30 times). The circadian rhythm of blood pressure and related dynamic parameters were observed before and after treatment in the two groups. (1) The differences of daytime average systolic blood pressure (dASBP), daytime average diastolic blood pressure (dADBP), nighttime average systolic blood pressure (nASBP) and circadian rhythm of systolic blood pressure before and after treatment were significant in the observation group (all P circadian rhythm of blood pressure and related dynamic parameters before and after treatment were insignificant in the control group (all P >0.05). The nASBP and circadian rhythm of systolic blood pressure in the observation group were significantly different from those in the control group (all P circadian rhythm of blood pressure in the observation group was higher than that in the control group ( P circadian rhythm of blood pressure and related dynamic parameters in patients with essential hypertension.

  6. Circadian rhythm in QT interval is preserved in mice deficient of potassium channel interacting protein 2

    DEFF Research Database (Denmark)

    Gottlieb, Lisa A; Lubberding, Anniek; Larsen, Anders Peter

    2017-01-01

    Potassium Channel Interacting Protein 2 (KChIP2) is suggested to be responsible for the circadian rhythm in repolarization duration, ventricular arrhythmias, and sudden cardiac death. We investigated the hypothesis that there is no circadian rhythm in QT interval in the absence of KChIP2. Implanted...... cardiac deaths were observed. We find similar diurnal (light:dark) and circadian (darkness) rhythms of RR intervals in WT and KChIP2(-/-) mice. Circadian rhythms in QT100 intervals are present in both groups, but at physiological small amplitudes: 1.6 ± 0.2 and 1.0 ± 0.3 ms in WT and KChIP2......(-/-), respectively (p = 0.15). A diurnal rhythm in QT100 intervals was only found in WT mice. QTmean-RR intervals display clear diurnal and circadian rhythms in both WT and KChIP2(-/-). The amplitude of the circadian rhythm in QTmean-RR is 4.0 ± 0.3 and 3.1 ± 0.5 ms in WT and KChIP2(-/-), respectively (p = 0...

  7. Timing Matters: Circadian Rhythm in Sepsis, Obstructive Lung Disease, Obstructive Sleep Apnea, and Cancer.

    Science.gov (United States)

    Truong, Kimberly K; Lam, Michael T; Grandner, Michael A; Sassoon, Catherine S; Malhotra, Atul

    2016-07-01

    Physiological and cellular functions operate in a 24-hour cyclical pattern orchestrated by an endogenous process known as the circadian rhythm. Circadian rhythms represent intrinsic oscillations of biological functions that allow for adaptation to cyclic environmental changes. Key clock genes that affect the persistence and periodicity of circadian rhythms include BMAL1/CLOCK, Period 1, Period 2, and Cryptochrome. Remarkable progress has been made in our understanding of circadian rhythms and their role in common medical conditions. A critical review of the literature supports the association between circadian misalignment and adverse health consequences in sepsis, obstructive lung disease, obstructive sleep apnea, and malignancy. Circadian misalignment plays an important role in these disease processes and can affect disease severity, treatment response, and survivorship. Normal inflammatory response to acute infections, airway resistance, upper airway collapsibility, and mitosis regulation follows a robust circadian pattern. Disruption of normal circadian rhythm at the molecular level affects severity of inflammation in sepsis, contributes to inflammatory responses in obstructive lung diseases, affects apnea length in obstructive sleep apnea, and increases risk for cancer. Chronotherapy is an underused practice of delivering therapy at optimal times to maximize efficacy and minimize toxicity. This approach has been shown to be advantageous in asthma and cancer management. In asthma, appropriate timing of medication administration improves treatment effectiveness. Properly timed chemotherapy may reduce treatment toxicities and maximize efficacy. Future research should focus on circadian rhythm disorders, role of circadian rhythm in other diseases, and modalities to restore and prevent circadian disruption.

  8. [The influence of interfered circadian rhythm on pregnancy and neonatal rats].

    Science.gov (United States)

    Chen, Wen-Jun; Sheng, Wen-Jie; Guo, Yin-Hua; Tan, Yong

    2015-10-25

    The aim of this study was to observe the influence of interfered circadian rhythm on pregnancy of rats and growth of neonatal rats, and to explore the relationship between the interfered circadian rhythm and the changes of melatonin and progesterone. Continuous light was used to inhibit melatonin secretion and therefore the interfered circadian rhythm animal model was obtained. The influence of interfered circadian rhythm on delivery of pregnant rats was observed. Serum was collected from rats during different stages of pregnancy to measure the concentrations of melatonin and progesterone. In order to observe the embryo resorption rate, half of pregnant rats were randomly selected to undergo a laparotomy, and the remainder was used to observe delivery and assess the growth of neonatal rats after delivery. The results showed that the interfered circadian rhythm induced adverse effects on pregnancy outcomes, including an increase of embryo resorption rate and a decrease in the number of live births; inhibited the secretion of melatonin along with decreased serum progesterone level; prolonged the stage of labor, but not the duration of pregnancy; and disturbed the fetal intrauterine growth and the growth of neonatal rats. The results suggest that interfered circadian rhythm condition made by continuous light could make adverse effects on both pregnant rats and neonatal rats. The results of our study may provide a way to modulate pregnant women's circadian rhythm and a possibility of application of melatonin on pregnant women.

  9. Enhanced timing abilities in percussionists generalize to rhythms without a musical beat.

    Science.gov (United States)

    Cameron, Daniel J; Grahn, Jessica A

    2014-01-01

    The ability to entrain movements to music is arguably universal, but it is unclear how specialized training may influence this. Previous research suggests that percussionists have superior temporal precision in perception and production tasks. Such superiority may be limited to temporal sequences that resemble real music or, alternatively, may generalize to musically implausible sequences. To test this, percussionists and nonpercussionists completed two tasks that used rhythmic sequences varying in musical plausibility. In the beat tapping task, participants tapped with the beat of a rhythmic sequence over 3 stages: finding the beat (as an initial sequence played), continuation of the beat (as a second sequence was introduced and played simultaneously), and switching to a second beat (the initial sequence finished, leaving only the second). The meters of the two sequences were either congruent or incongruent, as were their tempi (minimum inter-onset intervals). In the rhythm reproduction task, participants reproduced rhythms of four types, ranging from high to low musical plausibility: Metric simple rhythms induced a strong sense of the beat, metric complex rhythms induced a weaker sense of the beat, nonmetric rhythms had no beat, and jittered nonmetric rhythms also had no beat as well as low temporal predictability. For both tasks, percussionists performed more accurately than nonpercussionists. In addition, both groups were better with musically plausible than implausible conditions. Overall, the percussionists' superior abilities to entrain to, and reproduce, rhythms generalized to musically implausible sequences.

  10. Enhanced Timing Abilities in Percussionists Generalize to Rhythms Without a Musical Beat

    Directory of Open Access Journals (Sweden)

    Daniel J Cameron

    2014-12-01

    Full Text Available The ability to entrain movements to music is arguably universal, but it is unclear how specialized training may influence this. Previous research suggests that percussionists have superior temporal precision in perception and production tasks. Such superiority may be limited to temporal sequences that resemble real music or, alternatively, may generalize to musically implausible sequences. To test this, percussionists and nonpercussionists completed two tasks that used rhythmic sequences varying in musical plausibility. In the beat tapping task, participants tapped with the beat of a rhythmic sequence over 3 stages: finding the beat (as an initial sequence played, continuation of the beat (as a second sequence was introduced and played simultaneously, and switching to a second beat (the initial sequence finished, leaving only the second. The metres of the two sequences were either congruent or incongruent, as were their tempi (minimum inter-onset intervals. In the rhythm reproduction task, participants reproduced rhythms of four types, ranging from high to low musical plausibility: Metric simple rhythms induced a strong sense of the beat, metric complex rhythms induced a weaker sense of the beat, nonmetric rhythms had no beat, and jittered nonmetric rhythms also had no beat as well as low temporal predictability. For both tasks, percussionists performed more accurately than nonpercussionists. In addition, both groups were better with musically plausible than implausible conditions. Overall, the percussionists’ superior abilities to entrain to, and reproduce, rhythms generalized to musically implausible sequences.

  11. The Impact of Instrument-Specific Musical Training on Rhythm Perception and Production.

    Science.gov (United States)

    Matthews, Tomas E; Thibodeau, Joseph N L; Gunther, Brian P; Penhune, Virginia B

    2016-01-01

    Studies comparing musicians and non-musicians have shown that musical training can improve rhythmic perception and production. These findings tell us that training can result in rhythm processing advantages, but they do not tell us whether practicing a particular instrument could lead to specific effects on rhythm perception or production. The current study used a battery of four rhythm perception and production tasks that were designed to test both higher- and lower-level aspects of rhythm processing. Four groups of musicians (drummers, singers, pianists, string players) and a control group of non-musicians were tested. Within-task differences in performance showed that factors such as meter, metrical complexity, tempo, and beat phase significantly affected the ability to perceive and synchronize taps to a rhythm or beat. Musicians showed better performance on all rhythm tasks compared to non-musicians. Interestingly, our results revealed no significant differences between musician groups for the vast majority of task measures. This was despite the fact that all musicians were selected to have the majority of their training on the target instrument, had on average more than 10 years of experience on their instrument, and were currently practicing. These results suggest that general musical experience is more important than specialized musical experience with regards to perception and production of rhythms.

  12. A New Era of Courtship

    Directory of Open Access Journals (Sweden)

    Andrew Dix

    2013-12-01

    Full Text Available The central purpose of this study was to determine whether a single interpersonal communication event could influence perceptions of physical attractiveness in a dating environment. A total of 104 undergraduate students at a large United States university engaged in speed-dating in order to examine the effects of both positive communication and negative communication. Speed-dating was incorporated into the present research because this round-robin method of dating offered an efficient means for investigating attraction and analyzing the effects of a single conversation. It was upon arrival at the event that participants completed a pre-test measure, engaged in a series of three minute speed-dates, and then completed a post-test measure. Results produced evidence of an interaction. Perceptions of physical attractiveness increased from pre-test to post-test in the positive communication condition while perceptions of physical attractiveness decreased from pre-test to post-test in the negative communication condition. Additional findings illustrated that three minutes of non-neutral social interaction had differing effects on women and men. One of the central conclusions from the present research was that females can strategically use interpersonal communication as a tool for enhancing their physical appearance. The results from this study also yielded practical implications that are relevant to casual dating as well as theoretical implications that are germane to communication theory.

  13. A New Era of Courtship

    OpenAIRE

    Andrew Dix

    2013-01-01

    The central purpose of this study was to determine whether a single interpersonal communication event could influence perceptions of physical attractiveness in a dating environment. A total of 104 undergraduate students at a large United States university engaged in speed-dating in order to examine the effects of both positive communication and negative communication. Speed-dating was incorporated into the present research because this round-robin method of dating offered an efficient means f...

  14. Circadian rhythm disturbance after radiotherapy for brain tumor in infantile period

    International Nuclear Information System (INIS)

    Kubota, Masaya; Shinozaki, Masako; Sasaki, Hideo.

    1993-01-01

    We report a 19-year-old man suffering from circadian sleep-wake (S-W) rhythm disturbance after total tumor resection and whole brain irradiation. The patient was diagnosed as having astrocytoma in the right temporal lobe by CT scan and angiography at the age of 6 months. After total tumor resection and whole brain irradiation ( 60 Co 60 Gy), he showed profound psychomotor retardation, endoclinologic dysfunction including hypothyroidism and growth hormone deficiency, and S-W rhythm disturbance. At the age of 19, brain MRI revealed asymmetrical low intensity in the hypothalamic region. On endoclinological examination panhypopituitarism due to primary hypothalamic lesion was evident. His S-W rhythm was disturbed; i.e., sleep periods were dispersedly distributed throughout 24 hours. So he showed a lethargic tendency in the daytime. All-day polysomnography revealed abnormal sleep structure such as the absence of sleep spindle and hump, peripheral apnea, snoring and low oxygen saturation. After L-thyroxine supplementation his daily activity improved gradually. The decrease in short time sleep and tendency of a free-running rhythm were observed and oxygen saturation improved remarkably. Peripheral apnea and snoring disappeared. This wakening effect of L-thyroxine administration may be due to improvement of hypothyroidism symptom such as myxoedematous pharynx. It also seems related to the alteration of the central S-W rhythm regulation, because free-running rhythm appeared after L-thyroxine administration. Vitamin B 12 (VB 12 ), which has been reported to be effective for S-W rhythm disorders, was not effective for our patient's free-running rhythm. Compared with the patients responding to VB 12 , our patient's organic brain damage was more evident radiologically and endoclinologically. Following the hypothesis that VB 12 has a potential to reinforce the entrainment of circadian rhythm, our patient's organic brain damage may include entrainment system. (author)

  15. Internal Medicine Physicians’ Perceptions Regarding Rate versus Rhythm Control for Atrial Fibrillation

    Science.gov (United States)

    McCabe, James M.; Johnson, Colleen J; Marcus, Gregory M

    2011-01-01

    Atrial fibrillation (AF) is often managed by general internal medicine physicians. Available data suggest that guidelines regarding AF management are often not followed, but the reasons for this remain unknown. We sought to assess the knowledge and beliefs of internists regarding strategies to treat AF. We conducted a national electronic survey of internal medicine physicians regarding their perceptions of optimal AF management, with an emphasis on the rationale for choosing a rhythm or rate control strategy. One hundred and forty-eight physicians from 36 different states responded (representing at least 19% of unique e-mails opened). Half of the respondents reported managing their AF patients independently without referral to a cardiologist. Seventy-three percent of participants believe a rhythm control strategy conveys a decreased stroke risk, 64% believe there is a mortality benefit to rhythm control, and 55% think that it would help avoid long term anticoagulation. Comparing those who prefer a rhythm control strategy to everyone else, those who favor rhythm control statistically significantly more often believe that rhythm control reduces the risk for stroke (96% versus 67%, p=0.009) and that rhythm control allows for the discontinuation of anticoagulation therapy (76% versus 49%, p=0.045). In conclusion, contrary to available data in clinical trials and recent guidelines regarding the rationale for choosing a rhythm control strategy in treating AF, the majority of study participants believe that rhythm control decreases stroke risk, decreases mortality, and allows for discontinuation of anticoagulation therapy. These prevalent misconceptions may substantially contribute to guideline non-adherence. PMID:19195516

  16. Speech-like rhythm in a voiced and voiceless orangutan call.

    Directory of Open Access Journals (Sweden)

    Adriano R Lameira

    Full Text Available The evolutionary origins of speech remain obscure. Recently, it was proposed that speech derived from monkey facial signals which exhibit a speech-like rhythm of ∼5 open-close lip cycles per second. In monkeys, these signals may also be vocalized, offering a plausible evolutionary stepping stone towards speech. Three essential predictions remain, however, to be tested to assess this hypothesis' validity; (i Great apes, our closest relatives, should likewise produce 5Hz-rhythm signals, (ii speech-like rhythm should involve calls articulatorily similar to consonants and vowels given that speech rhythm is the direct product of stringing together these two basic elements, and (iii speech-like rhythm should be experience-based. Via cinematic analyses we demonstrate that an ex-entertainment orangutan produces two calls at a speech-like rhythm, coined "clicks" and "faux-speech." Like voiceless consonants, clicks required no vocal fold action, but did involve independent manoeuvring over lips and tongue. In parallel to vowels, faux-speech showed harmonic and formant modulations, implying vocal fold and supralaryngeal action. This rhythm was several times faster than orangutan chewing rates, as observed in monkeys and humans. Critically, this rhythm was seven-fold faster, and contextually distinct, than any other known rhythmic calls described to date in the largest database of the orangutan repertoire ever assembled. The first two predictions advanced by this study are validated and, based on parsimony and exclusion of potential alternative explanations, initial support is given to the third prediction. Irrespectively of the putative origins of these calls and underlying mechanisms, our findings demonstrate irrevocably that great apes are not respiratorily, articulatorilly, or neurologically constrained for the production of consonant- and vowel-like calls at speech rhythm. Orangutan clicks and faux-speech confirm the importance of rhythmic speech

  17. Right- and left-brain hemisphere. Rhythm in reaction time to light signals is task-load-dependent: age, gender, and handgrip strength rhythm comparisons.

    Science.gov (United States)

    Reinberg, Alain; Bicakova-Rocher, Alena; Mechkouri, Mohamed; Ashkenazi, Israel

    2002-11-01

    In healthy mature subjects simple reaction time (SRT) to a single light signal (an easy task) is associated with a prominent rhythm with tau = 24 h of dominant (DH) as well as nondominant (NDH) hand performance, while three-choice reaction time (CRT), a complex task, is associated with tau = 24 h of the DH but tau gender on the difference in tau of the NDH and DH, as it relates to the corresponding cortical hemisphere of the brain, in comparison to the rhythm in handgrip strength. Healthy subjects, 9 (5 M and 4 F) adolescents 10-16 yr of age and 15 (8 M and 7 F) adults 18-67 yr of age, active between 08:00 +/- 1 h and 23:00 +/- 1:30 h and free of alcohol, tobacco, and drug consumption volunteered. Data were gathered longitudinally at home and work 4-7 times daily for 11-20 d. At each test time the following variables were assessed: grip strength of both hands (Dynamometer: Colin-Gentile, Paris, France); single reaction time to a yellow signal (SRT); and CRT to randomized yellow, red, or green signal series with varying instruction from test to test (Psycholog-24: Biophyderm, France). Rhythms in the performance in SRT, CRT, and handgrip strength of both DH and NDH were explored. The sleep-wake rhythm was assessed by sleep-logs, and in a subset of 14 subjects it was also assessed by wrist actigraphy (Mini-Motionlogger: AMI, Ardsley NY). Exploration of the prominent period tau of time series was achieved by a special power spectra analysis for unequally spaced data. Cosinor analysis was used to quantify the rhythm amplitude A and rhythm-adjusted mean M of the power spectral analysis determined trial tau. A 24h sleep-wake rhythm was detected in almost all cases. In adults, a prominent tau of 24 h characterized the performance of the easy task by both the DH and NDH. In adults a prominent tau of 24 h was also detected in the complex CRT task performed by the DH, but for the NDH the tau was gender-related but was age-related since it was seldom observed in adolescent

  18. Algorithm for personal identification in distance learning system based on registration of keyboard rhythm

    Science.gov (United States)

    Nikitin, P. V.; Savinov, A. N.; Bazhenov, R. I.; Sivandaev, S. V.

    2018-05-01

    The article describes the method of identifying a person in distance learning systems based on a keyboard rhythm. An algorithm for the organization of access control is proposed, which implements authentication, identification and verification of a person using the keyboard rhythm. Authentication methods based on biometric personal parameters, including those based on the keyboard rhythm, due to the inexistence of biometric characteristics without a particular person, are able to provide an advanced accuracy and inability to refuse authorship and convenience for operators of automated systems, in comparison with other methods of conformity checking. Methods of permanent hidden keyboard monitoring allow detecting the substitution of a student and blocking the key system.

  19. Chapter 11 - Electrical Coupling in the Generation of Vertebrate Motor Rhythms

    DEFF Research Database (Denmark)

    Li, W.C.; Rekling, Jens Christian

    2017-01-01

    Many forms of vertebrate motor activity like chewing, breathing, and locomotion are rhythmic. This requires synchronized discharges of motoneurons controlling different muscle groups in an orchestrated manner. We provide a brief review of the presence and role of electrical coupling in a few well...... of electrical coupling in vertebrate motor rhythms appears to be critically dependent on developmental age, with more crucial functions in the early postnatal period than in the adult.......-studied systems: the pacemaker nucleus in weakly electric fish; mesencephalic trigeminal nucleus involved in chewing rhythms; mammalian spinal motoneurons and excitatory interneurons in the Xenopus tadpole swimming circuit, brainstem circuits underlying breathing rhythm, and central respiratory chemosensitivity...

  20. Circadian rhythms in the pineal organ persist in zebrafish larvae that lack ventral brain

    Directory of Open Access Journals (Sweden)

    Goldstein-Kral Lauren

    2011-01-01

    Full Text Available Abstract Background The mammalian suprachiasmatic nucleus (SCN, located in the ventral hypothalamus, is a major regulator of circadian rhythms in mammals and birds. However, the role of the SCN in lower vertebrates remains poorly understood. Zebrafish cyclops (cyc mutants lack ventral brain, including the region that gives rise to the SCN. We have used cyc embryos to define the function of the zebrafish SCN in regulating circadian rhythms in the developing pineal organ. The pineal organ is the major source of the circadian hormone melatonin, which regulates rhythms such as daily rest/activity cycles. Mammalian pineal rhythms are controlled almost exclusively by the SCN. In zebrafish and many other lower vertebrates, the pineal has an endogenous clock that is responsible in part for cyclic melatonin biosynthesis and gene expression. Results We find that pineal rhythms are present in cyc mutants despite the absence of an SCN. The arginine vasopressin-like protein (Avpl, formerly called Vasotocin is a peptide hormone expressed in and around the SCN. We find avpl mRNA is absent in cyc mutants, supporting previous work suggesting the SCN is missing. In contrast, expression of the putative circadian clock genes, cryptochrome 1b (cry1b and cryptochrome 3 (cry3, in the brain of the developing fish is unaltered. Expression of two pineal rhythmic genes, exo-rhodopsin (exorh and serotonin-N-acetyltransferase (aanat2, involved in photoreception and melatonin synthesis, respectively, is also similar between cyc embryos and their wildtype (WT siblings. The timing of the peaks and troughs of expression are the same, although the amplitude of expression is slightly decreased in the mutants. Cyclic gene expression persists for two days in cyc embryos transferred to constant light or constant dark, suggesting a circadian clock is driving the rhythms. However, the amplitude of rhythms in cyc mutants kept in constant conditions decreased more quickly than in their

  1. Rhythm-based Analysis As A Different Way Of Viewing Work Life In A School

    DEFF Research Database (Denmark)

    Clausen, Jacob

    This abstract is about rhythms and how professionals struggle to balance two categories of rhythms in a public school. The teachers at this school clearly expressed that they had a common denominator in regards to their work life, being that they did not have enough time to do their work....... Their understanding of time were always audible and they were very verbal about their frustrations in relation to time (pressure). The full article is about rhythms in a specific public school as a way to gather a new perspective on work life....

  2. The rhythm and tempo of the game of highly qualified teams

    Directory of Open Access Journals (Sweden)

    V’yacheslav Mulik

    2015-06-01

    Full Text Available Purpose: to set indicators of rhythm and tempo of the game teams of high qualification. Material and Methods: analysis of the scientific-methodical literature, registration of technical-tactical actions, methods of mathematical statistics. The study of competitive activities was conducted with participating teams of world championship 2014. Results: the acticle shows indicators of the rhythm and tempo of the game of well-qualified teams. Conclusions: teams-winners have surpassed teams that concede in terms of indicators of passes the ball, shots at goal, the rhythm of the game, tempo of game.

  3. Frailty syndrome in patients with heart rhythm disorders.

    Science.gov (United States)

    Mlynarska, Agnieszka; Mlynarski, Rafal; Golba, Krzysztof S

    2017-09-01

    To assess the prevalence of frailty syndrome in patients with heart rhythm disorders that qualified for pacemaker implantation. The study included 171 patients (83 women, aged 73.9 ± 6.7 years) who qualified for pacemaker implantation as a result of sinus node dysfunction (81 patients) or atrio-ventricular blocks (AVB; 90 patients). A total of 60 patients (25 women, aged 72.40 ± 7.09 years) without heart rhythm disorders were included in the control group. Frailty syndrome was diagnosed using the Canadian Study of Health and Aging Clinical Frailty Scale test. Frailty syndrome was diagnosed in 25.15% of the patients, and pre-frailty in 36.84% of the patients. Frailty syndrome was diagnosed in 10% of the control group, and the average value of frailty was 3.35 ± 0.92. Frailty occurred significantly more often among patients with AVB (33.34%) compared with patients who were diagnosed with sinus node dysfunction (16.05%); P = 0.0081. The average score of frailty for sinus node dysfunction was 3.71 ± 0.89, and for AVB it was 4.14 ± 0.93; P = 0.0152. In the case of AVB, the women had a statistically more intense level of frailty of 4.54 ± 0.90 as compared with the men 3.87 ± 0.85; P = 0.0294. In the multiple logistic analysis, the presence of any arrhythmia was strongly associated with frailty syndrome (OR 2.1286, 95% CI 1.4594 - 3.1049; P = 0.0001). Frailty syndrome was diagnosed in one-quarter of patients with cardiac arrhythmias, whereas a further 40% were at a higher risk of frailty syndrome, and its occurrence was significantly higher if compared with the control group. Frailty occurred significantly more often among patients with atrio-ventricular blocks, especially in women. The results of the present research showed that there is a statistical association between frailty and arrhythmias. Geriatr Gerontol Int 2017; 17: 1313-1318. © 2016 Japan Geriatrics Society.

  4. Introduction to Focus Issue: Rhythms and Dynamic Transitions in Neurological Disease: Modeling, Computation, and Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kaper, Tasso J., E-mail: tasso@bu.edu; Kramer, Mark A., E-mail: mak@bu.edu [Department of Mathematics and Statistics, Boston University, Boston, Massachusetts 02215 (United States); Rotstein, Horacio G., E-mail: horacio@njit.edu [Department of Mathematical Sciences, New Jersey Institute of Technology, Newark, New Jersey 07102 (United States)

    2013-12-15

    Rhythmic neuronal oscillations across a broad range of frequencies, as well as spatiotemporal phenomena, such as waves and bumps, have been observed in various areas of the brain and proposed as critical to brain function. While there is a long and distinguished history of studying rhythms in nerve cells and neuronal networks in healthy organisms, the association and analysis of rhythms to diseases are more recent developments. Indeed, it is now thought that certain aspects of diseases of the nervous system, such as epilepsy, schizophrenia, Parkinson's, and sleep disorders, are associated with transitions or disruptions of neurological rhythms. This focus issue brings together articles presenting modeling, computational, analytical, and experimental perspectives about rhythms and dynamic transitions between them that are associated to various diseases.

  5. Junctional rhythm occurring during AV nodal reentrant tachycardia ablation, is it different among Egyptians?

    Directory of Open Access Journals (Sweden)

    Ayman M. Abdel Moteleb

    2013-12-01

    Conclusion: Junctional rhythm is a sensitive predictor of successful ablation. The pattern of JR is a useful predictor of successful ablation. Egyptian population has distinctive patterns of JR during AVNRT ablation.

  6. Suprachiasmatic Nucleus Interaction with the Arcuate Nucleus; Essential for Organizing Physiological Rhythms

    NARCIS (Netherlands)

    Buijs, Frederik N.; Guzmán-Ruiz, Mara; León-Mercado, Luis; Basualdo, Mari Carmen; Escobar, Carolina; Kalsbeek, Andries; Buijs, Ruud M.

    2017-01-01

    The suprachiasmatic nucleus (SCN) is generally considered the master clock, independently driving all circadian rhythms. We recently demonstrated the SCN receives metabolic and cardiovascular feedback adeptly altering its neuronal activity. In the present study, we show that microcuts effectively

  7. Circadian rhythms in healthy aging--effects downstream from the pacemaker

    Science.gov (United States)

    Monk, T. H.; Kupfer, D. J.

    2000-01-01

    Using both previously published findings and entirely new data, we present evidence in support of the argument that the circadian dysfunction of advancing age in the healthy human is primarily one of failing to transduce the circadian signal from the circadian timing system (CTS) to rhythms "downstream" from the pacemaker rather than one of failing to generate the circadian signal itself. Two downstream rhythms are considered: subjective alertness and objective performance. For subjective alertness, we show that in both normal nychthemeral (24 h routine, sleeping at night) and unmasking (36 h of constant wakeful bed rest) conditions, advancing age, especially in men, leads to flattening of subjective alertness rhythms, even when circadian temperature rhythms are relatively robust. For objective performance, an unmasking experiment involving manual dexterity, visual search, and visual vigilance tasks was used to demonstrate that the relationship between temperature and performance is strong in the young, but not in older subjects (and especially not in older men).

  8. Effects of noradrenaline on locomotor rhythm-generating networks in the isolated neonatal rat spinal cord

    DEFF Research Database (Denmark)

    Kiehn, O; Sillar, K T; Kjaerulff, O

    1999-01-01

    locomotor-like rhythm, in which activity alternated between the left and right sides, and between rostral and caudal roots on the same side. As shown previously, stable locomotor activity could be induced by bath application of N-methyl-D-aspartate (NMDA; 4-8.5 microM) and/or serotonin (5-HT; 4-20 micro......M). NA modulated this activity by decreasing the cycle frequency and increasing the ventral root burst duration. These effects were dose dependent in the concentration range 1-5 microM. In contrast, at no concentration tested did NA have consistent effects on burst amplitudes or on the background...... activity of the ongoing rhythm. Moreover, NA did not obviously affect the left/right and rostrocaudal alternation of the NMDA/5-HT rhythm. The NMDA/5-HT locomotor rhythm sometimes displayed a time-dependent breakdown in coordination, ultimately resulting in tonic ventral root activity. However...

  9. Neural Correlates of Phrase Rhythm: An EEG Study of Bipartite vs. Rondo Sonata Form

    Directory of Open Access Journals (Sweden)

    Antonio Fernández-Caballero

    2017-04-01

    Full Text Available This paper introduces the neural correlates of phrase rhythm. In short, phrase rhythm is the rhythmic aspect of phrase construction and the relationships between phrases. For the sake of establishing the neural correlates, a musical experiment has been designed to induce music-evoked stimuli related to phrase rhythm. Brain activity is monitored through electroencephalography (EEG by using a brain–computer interface. The power spectral value of each EEG channel is estimated to obtain how power variance distributes as a function of frequency. Our experiment shows statistical differences in theta and alpha bands in the phrase rhythm variations of two classical sonatas, one in bipartite form and the other in rondo form.

  10. Spinal Hb9::Cre-derived excitatory interneurons contribute to rhythm generation in the mouse

    DEFF Research Database (Denmark)

    Caldeira, Vanessa; Dougherty, Kimberly J.; Borgius, Lotta

    2017-01-01

    Rhythm generating neurons are thought to be ipsilaterally-projecting excitatory neurons in the thoracolumbar mammalian spinal cord. Recently, a subset of Shox2 interneurons (Shox2 non-V2a INs) was found to fulfill these criteria and make up a fraction of the rhythm-generating population. Here we...... than in cords from controls. Collectively, our findings indicate that excitatory Hb9::Cre-derived INs constitute a distinct population of neurons that participates in the rhythm generating kernel for spinal locomotion....... use Hb9::Cre mice to genetically manipulate Hb9::Cre-derived excitatory interneurons (INs) in order to determine the role of these INs in rhythm generation. We demonstrate that this line captures a consistent population of spinal INs which is mixed with respect to neurotransmitter phenotype...

  11. The state of immune system circadian rhythms in rats at exposure to ionizing radiation

    International Nuclear Information System (INIS)

    Kuz'menko, O.V.; Nyikyiforova, N.A.; Yivanenko, M.O.

    2010-01-01

    Circadian rhythms of the immune system parameters restoration in rats with different response to stress, exposed to single total irradiation at dose of 6 Gy at various time of the day was investigated.

  12. Alteration of circadian rhythm during epileptogenesis: implications for the suprachiasmatic nucleus circuits.

    Science.gov (United States)

    Xiang, Yan; Li, Zhi-Xiao; Zhang, Ding-Yu; He, Zhi-Gang; Hu, Ji; Xiang, Hong-Bing

    2017-01-01

    It is important to realize that characterization of the circadian rhythm patterns of seizure occurrence can implicate in diagnosis and treatment of selected types of epilepsy. Evidence suggests a role for the suprachiasmatic nucleus (SCN) circuits in overall circadian rhythm and seizure susceptibility both in animals and humans. Thus, we conclude that SCN circuits may exert modifying effects on circadian rhythmicity and neuronal excitability during epileptogenesis. SCN circuits will be studied in our brain centre and collaborating centres to explore further the interaction between the circadian rhythm and epileptic seizures. More and thorough research is warranted to provide insight into epileptic seizures with circadian disruption comorbidities such as disorders of cardiovascular parameters and core body temperature circadian rhythms.

  13. Circadian Rhythm Disturbances in Mood Disorders: Insights into the Role of the Suprachiasmatic Nucleus

    Science.gov (United States)

    2017-01-01

    Circadian rhythm disturbances are a common symptom among individuals with mood disorders. The suprachiasmatic nucleus (SCN), in the ventral part of the anterior hypothalamus, orchestrates physiological and behavioral circadian rhythms. The SCN consists of self-sustaining oscillators and receives photic and nonphotic cues, which entrain the SCN to the external environment. In turn, through synaptic and hormonal mechanisms, the SCN can drive and synchronize circadian rhythms in extra-SCN brain regions and peripheral tissues. Thus, genetic or environmental perturbations of SCN rhythms could disrupt brain regions more closely related to mood regulation and cause mood disturbances. Here, we review clinical and preclinical studies that provide evidence both for and against a causal role for the SCN in mood disorders. PMID:29230328

  14. Introduction to Focus Issue: Rhythms and Dynamic Transitions in Neurological Disease: Modeling, Computation, and Experiment

    International Nuclear Information System (INIS)

    Kaper, Tasso J.; Kramer, Mark A.; Rotstein, Horacio G.

    2013-01-01

    Rhythmic neuronal oscillations across a broad range of frequencies, as well as spatiotemporal phenomena, such as waves and bumps, have been observed in various areas of the brain and proposed as critical to brain function. While there is a long and distinguished history of studying rhythms in nerve cells and neuronal networks in healthy organisms, the association and analysis of rhythms to diseases are more recent developments. Indeed, it is now thought that certain aspects of diseases of the nervous system, such as epilepsy, schizophrenia, Parkinson's, and sleep disorders, are associated with transitions or disruptions of neurological rhythms. This focus issue brings together articles presenting modeling, computational, analytical, and experimental perspectives about rhythms and dynamic transitions between them that are associated to various diseases

  15. Impacts of nurses’ circadian rhythm sleep disorders, fatigue, and depression on medication administration errors

    Directory of Open Access Journals (Sweden)

    Abdelbaset M. Saleh

    2014-01-01

    Conclusions: Medication administration errors, fatigue and depression were all significantly affected by circadian sleep disorders. An administration’s control of work flow to provide convenient sleep hours will help in improving sleep circadian rhythms and consequently minimize these problems.

  16. [NEUROSEMANTIC AND PSYCHOPHYSIOLOGICAL CORRELATES OF RHYTHM-SUGGESTIVE CORRECTION OF STRESS CONDITIONS].

    Science.gov (United States)

    Ushakov, I B; Ivanov, A V; Kvasovets, S V; Bubeev, Yu A

    2015-01-01

    Correlates of successful rhythm-suggestive compensation of stress in sportsmen with neurotic symptoms developed in consequence of painful experience of failure were studied. Effectiveness of the rhythm-suggestive and rational psychological methods was compared by measuring the evoked potentials response to emotionally significant extramental verbal stimuli and images, and using psychophysiological test MASTER to track dynamics of a number of body functional parameters. The rational compensation has been shown to reduce the psychic tension and to set right the voluntary control process. Rhythm-suggestive programs are good for compensation of post-stress emotions and affectations, and the involuntary control process. It was found that correction potentialities of the rhythm-suggestive programs together with the psychodiagnostic advantages of test MASTER are promising instruments for dynamic monitoring of the mental state with the aim to prevent workplace stresses and to provide rehabilitation treatment of aftermaths.

  17. Increase in Synchronization of Autonomic Rhythms between Individuals When Listening to Music

    Science.gov (United States)

    Bernardi, Nicolò F.; Codrons, Erwan; di Leo, Rita; Vandoni, Matteo; Cavallaro, Filippo; Vita, Giuseppe; Bernardi, Luciano

    2017-01-01

    In light of theories postulating a role for music in forming emotional and social bonds, here we investigated whether endogenous rhythms synchronize between multiple individuals when listening to music. Cardiovascular and respiratory recordings were taken from multiple individuals (musically trained or music-naïve) simultaneously, at rest and during a live concert comprising music excerpts with varying degrees of complexity of the acoustic envelope. Inter-individual synchronization of cardiorespiratory rhythms showed a subtle but reliable increase during passively listening to music compared to baseline. The low-level auditory features of the music were largely responsible for creating or disrupting such synchronism, explaining ~80% of its variance, over and beyond subjective musical preferences and previous musical training. Listening to simple rhythms and melodies, which largely dominate the choice of music during rituals and mass events, brings individuals together in terms of their physiological rhythms, which could explain why music is widely used to favor social bonds. PMID:29089898

  18. Rhythm vs. rate control of atrial fibrillation meta-analysed by number needed to treat

    OpenAIRE

    Kumana, Cyrus R; Cheung, Bernard M Y; Cheung, Giselle T Y; Ovedal, Tori; Pederson, Bjorn; Lauder, Ian J

    2005-01-01

    Background: Whenever feasible, rhythm control of atrial fibrillation (AF) was generally preferred over rate control, in the belief that it offered better symptomatic relief and quality of life, and eliminated the need for anticoagulation. However, recent trials appear to challenge these assumptions. Aims: To explore the desirability of rhythm vs. rate control of AF by systematic review of pertinent, published, randomized controlled trials (RCTs) and a meta-analysis by number needed to treat (...

  19. Natural Rhythms and Temporal Perception - Visualization of Sunlight Patterns with Energy Monitoring

    OpenAIRE

    Opitz, Christoph

    2018-01-01

    In his book Ritual House, Ralph Knowles states, "The houses we inhabit, the cities surrounding our houses, even the clothes we wear - all are shelters we erect against the elements. But they are also manifestations of ancient rituals, developed in response to nature's rhythms" (2006). Implicit within this quote is the importance of nature's rhythms in our lives, particularly those related to the movement of the sun. Many built environments have no connection to the exterior. Those who work i...

  20. Circadian rhythm disruption was observed in hand, foot, and mouth disease patients.

    Science.gov (United States)

    Zhu, Yu; Jiang, Zhou; Xiao, Guoguang; Cheng, Suting; Wen, Yang; Wan, Chaomin

    2015-03-01

    Hand, foot, and mouth disease (HFMD) with central nerve system complications may rapidly progress to fulminated cardiorespiratory failure, with higher mortality and worse prognosis. It has been reported that circadian rhythms of heart rate (HR) and respiratory rate are useful in predicting prognosis of severe cardiovascular and neurological diseases. The present study aims to investigate the characteristics of the circadian rhythms of HR, respiratory rate, and temperature in HFMD patients with neurological complications. Hospitalized HFMD patients including 33 common cases (common group), 61 severe cases (severe group), and 9 critical cases (critical group) were contrasted retrospectively. Their HR, respiratory rate, and temperatures were measured every 4 hours during the first 48-hour in the hospital. Data were analyzed with the least-squares fit of a 24-hour cosine function by the single cosinor and population-mean cosinor method. Results of population-mean cosinor analysis demonstrated that the circadian rhythm of HR, respiratory rate, and temperature was present in the common and severe group, but absent in the critical group. The midline-estimating statistic of rhythm (MESOR) (P = 0.016) and acrophase (P circadian characteristics of HR among 3 groups. Compared with the common group, the MESOR of temperature and respiratory rate was significantly higher, and acrophase of temperature and respiratory rate was 2 hours ahead in the severe group, critical HFMD patients lost their population-circadian rhythm of temperature, HR, and respiratory rate. The high values of temperature and respiratory rate for the common group were concentrated between 3 and 9 PM, whereas those for the severe group were more dispersive. And the high values for the critical group were equally distributed in 24 hours of the day. Circadian rhythm of patients' temperature in the common group was the same as the normal rhythm of human body temperature. Circadian rhythm of patients

  1. Calcium Channel Genes Associated with Bipolar Disorder Modulate Lithium's Amplification of Circadian Rhythms

    Science.gov (United States)

    McCarthy, Michael J.; LeRoux, Melissa; Wei, Heather; Beesley, Stephen; Kelsoe, John R.; Welsh, David K.

    2015-01-01

    Bipolar disorder (BD) is associated with mood episodes and low amplitude circadian rhythms. Previously, we demonstrated that fibroblasts grown from BD patients show weaker amplification of circadian rhythms by lithium compared to control cells. Since calcium signals impact upon the circadian clock, and L-type calcium channels (LTCC) have emerged as genetic risk factors for BD, we examined whether loss of function in LTCCs accounts for the attenuated response to lithium in BD cells. We used fluorescent dyes to measure Ca2+ changes in BD and control fibroblasts after lithium treatment, and bioluminescent reporters to measure Per2∷luc rhythms in fibroblasts from BD patients, human controls, and mice while pharmacologically or genetically manipulating calcium channels. Longitudinal expression of LTCC genes (CACNA1C, CACNA1D and CACNB3) was then measured over 12-24 hr in BD and control cells. Our results indicate that independently of LTCCs, lithium stimulated intracellular Ca2+ less effectively in BD vs. control fibroblasts. In longitudinal studies, pharmacological inhibition of LTCCs or knockdown of CACNA1A, CACNA1C, CACNA1D and CACNB3 altered circadian rhythm amplitude. Diltiazem and knockdown of CACNA1C or CACNA1D eliminated lithium's ability to amplify rhythms. Knockdown of CACNA1A or CACNB3 altered baseline rhythms, but did not affect rhythm amplification by lithium. In human fibroblasts, CACNA1C genotype predicted the amplitude response to lithium, and the expression profiles of CACNA1C, CACNA1D and CACNB3 were altered in BD vs. controls. We conclude that in cells from BD patients, calcium signaling is abnormal, and that LTCCs underlie the failure of lithium to amplify circadian rhythms. PMID:26476274

  2. Circadian rhythm of pineal uptake of 32P in domestic fowl

    International Nuclear Information System (INIS)

    Sackman, J.W.

    1977-01-01

    The uptake of radioactive phosphorus by the pineal gland in White Leghorn cockerels (Gallus domesticus) showed a diurnal variation with maxima in the light phase and minima in the dark phase of the light: dark cycle. Constant light caused the rhythm to disappear while constant dark had no effect other than lowering the amplitude of the variations. These data indicate that the rhythm in pineal uptake of 32 P is circadian. (author)

  3. Weak circadian rhythm increases neutropenia risk among breast cancer patients undergoing adjuvant chemotherapy.

    Science.gov (United States)

    Li, Wentao; Kwok, Carol Chi-Hei; Chan, Dominic Chun-Wan; Wang, Feng; Tse, Lap Ah

    2018-04-01

    Severe neutropenia is a common dose-limiting side effect of adjuvant breast cancer chemotherapy. We aimed to test the hypothesis that weak circadian rhythm is associated with an increased risk of neutropenia using a cohort study. We consecutively recruited 193 breast cancer patients who received adjuvant chemotherapy (5-fluorouracil, epirubicin, and cyclophosphamide followed by docetaxel; doxorubicin and cyclophosphamide; docetaxel and cyclophosphamide). Participants wore a wrist actigraph continuously for 168 h at the beginning of chemotherapy. Values of percent rhythm and double amplitude below medians represented weak circadian rhythm. Mesor measured the mean activity level and acrophase symboled the peak time of the rhythm. We used Cox proportional hazard regression model to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) of grade 4 neutropenia and febrile neutropenia in relation to actigraphy-derived parameters. Low levels of percent rhythm (HR:2.59, 95% CI 1.50-4.72), double amplitude (HR:2.70, 95% CI 1.51-4.85), and mesor (HR: 2.48, 95% CI 1.44-4.29) were positively associated with the risk of grade 4 neutropenia during chemotherapy. Low levels of percent rhythm (HR: 2.41, 95% CI 1.02-5.69) and double amplitude (HR:2.49, 95% CI 1.05-5.90) were also associated with increased risks of febrile neutropenia. The HRs for acrophase were not statistically significant. This study provides the first epidemiological evidence that increased risks of grade 4 neutropenia and febrile neutropenia are associated with weak circadian rhythm among adjuvant breast cancer patients. The results suggest that circadian rhythm might be one potential target for the prevention of chemotherapy-induced neutropenia among cancer patients.

  4. Recognition memory for vibrotactile rhythms: an fMRI study in blind and sighted individuals.

    Science.gov (United States)

    Sinclair, Robert J; Dixit, Sachin; Burton, Harold

    2011-01-01

    Calcarine sulcal cortex possibly contributes to semantic recognition memory in early blind (EB). We assessed a recognition memory role using vibrotactile rhythms and a retrieval success paradigm involving learned "old" and "new" rhythms in EB and sighted. EB showed no activation differences in occipital cortex indicating retrieval success but replicated findings of somatosensory processing. Both groups showed retrieval success in primary somatosensory, precuneus, and orbitofrontal cortex. The S1 activity might indicate generic sensory memory processes.

  5. Environmental factors contributed to circannual rhythm of semen quality.

    Science.gov (United States)

    Mao, Huan; Feng, Lei; Yang, Wan-Xi

    2017-01-01

    We investigated whether human semen parameters present circannual rhythm or not, and whether environmental factors exert on semen quality. This retrospective study used data of patients mainly from Reproductive Medicine Center and Urology and Andrology Clinic of a general hospital in China. Sperm concentration and motility were measured by computer aided sperm analysis (CASA). Sperm morphology was scored based on the strict criteria (WHO, 2010). The Kruskal-Wallis rank test was used to investigate the relationship between semen parameters and season/month. Partial correlation coefficients were used to analyze the relationship between semen parameters and environmental factors. In this study, we found that sperm concentration and total amount per ejaculate were significantly lower in summer and higher in winter. But, sperm progressive motility and motility were significantly higher in spring and summer (from March to June), lower in autumn and winter (September and October). Unexpectedly, normal sperm morphology and mixed agglutination reaction (MAR) positive rate didn't vary along with season or month. Furthermore, temperature was negatively related to sperm concentration and total amount per ejaculate. Precipitation was positively associated with progressive motility and normal sperm morphology, but negatively related to sperm head defect percentage. The length of sunlight was positively related to progressive motility. The Air Quality Index (AQI) was positively associated with semen volume and sperm total amount per ejaculate. These suggest seasonal and monthly variation underlying some semen parameters.

  6. Dynamic correlations between heart and brain rhythm during Autogenic meditation

    Science.gov (United States)

    Kim, Dae-Keun; Lee, Kyung-Mi; Kim, Jongwha; Whang, Min-Cheol; Kang, Seung Wan

    2013-01-01

    This study is aimed to determine significant physiological parameters of brain and heart under meditative state, both in each activities and their dynamic correlations. Electrophysiological changes in response to meditation were explored in 12 healthy volunteers who completed 8 weeks of a basic training course in autogenic meditation. Heart coherence, representing the degree of ordering in oscillation of heart rhythm intervals, increased significantly during meditation. Relative EEG alpha power and alpha lagged coherence also increased. A significant slowing of parietal peak alpha frequency was observed. Parietal peak alpha power increased with increasing heart coherence during meditation, but no such relationship was observed during baseline. Average alpha lagged coherence also increased with increasing heart coherence during meditation, but weak opposite relationship was observed at baseline. Relative alpha power increased with increasing heart coherence during both meditation and baseline periods. Heart coherence can be a cardiac marker for the meditative state and also may be a general marker for the meditative state since heart coherence is strongly correlated with EEG alpha activities. It is expected that increasing heart coherence and the accompanying EEG alpha activations, heart brain synchronicity, would help recover physiological synchrony following a period of homeostatic depletion. PMID:23914165

  7. Evolution of circadian rhythms: from bacteria to human.

    Science.gov (United States)

    Bhadra, Utpal; Thakkar, Nirav; Das, Paromita; Pal Bhadra, Manika

    2017-07-01

    The human body persists in its rhythm as per its initial time zone, and transition always occur according to solar movements around the earth over 24 h. While traveling across different latitudes and longitudes, at the pace exceeding the earth's movement, the changes in the external cues exceed the level of toleration of the body's biological clock. This poses an alteration in our physiological activities of sleep-wake pattern, mental alertness, organ movement, and eating habits, causing them to temporarily lose the track of time. This is further re-synchronized with the physiological cues of the destination over time. The mechanism of resetting of the clocks with varying time zones and cues occur in organisms from bacteria to humans. It is the result of the evolution of different pathways and molecular mechanisms over the time. There has been evolution of numerous comprehensive mechanisms using various research tools to get a deeper insight into the rapid turnover of molecular mechanisms in various species. This review reports insights into the evolution of the circadian mechanism and its evolutionary shift which is vital and plays a major role in assisting different organisms to adapt in different zones and controls their internal biological clocks with changing external cues. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Proceedings from Heart Rhythm Society’s Emerging Technologies Forum

    Science.gov (United States)

    Zeitler, Emily P.; Al-Khatib, Sana M.; Slotwiner, David; Kumar, Uday N.; Varosy, Paul; Van Wagoner, David R.; Marcus, Gregory M.; Kusumoto, Fred M.; Blum, Laura

    2015-01-01

    Physicians are in an excellent position to significantly contribute to medical device innovation, but the process of bringing an idea to the bedside is complex. To begin to address these perceived barriers, the Heart Rhythm Society (HRS) convened a forum of stakeholders in medical device innovation in conjunction with the 2015 HRS Scientific Sessions. The forum facilitated open discussion about medical device innovation, including obstacles to physician involvement and possible solutions. This report is based on the themes that emerged. First, physician innovators must take an organized approach to identifying unmet clinical needs and potential solutions. Second, extensive funds, usually secured through solicitation for investment, are often required to achieve meaningful progress developing an idea into a device. Third, planning for regulatory requirements of the U.S. Food & Drug Administration (FDA) and Centers for Medicare and Medicaid Services (CMS) is essential. In addition to these issues, intellectual property and overall trends in health care, including international markets, are critically relevant considerations for the physician innovator. Importantly, there are a number of ways in which professional societies can assist physician innovators to navigate the complex medical device innovation landscape, bring clinically meaningful devices to market more quickly, and ultimately improve patient care. These efforts include facilitating interaction between potential collaborators through scientific meetings and other gatherings; collecting, evaluating, and disseminating state-of-the-art scientific information; and representing the interests of members in interactions with regulators and policy makers. PMID:26801401

  9. Rhythm and Structure: Brecht’s Antigone in performance

    Directory of Open Access Journals (Sweden)

    Bruno C. Duarte

    2017-01-01

    Full Text Available Brecht’s adaptation of Sophocles’ Antigone in 1948 was openly a political gesture that aspired to the complete rationalization of Greek Tragedy. From the beginning, Brecht made it his task to wrench ancient tragic poetry out of its “ideological haze”, and proceeded to dismantle and eliminate what he named the “element of fate”, the crucial substance of tragic myth itself. However, his encounter with Hölderlin's unorthodox translation of Antigone, the main source for his appropriation and rewriting of the play, led him to engage in a radical experiment in theatrical practice. From the isolated first performance of Antigone, a model was created – the Antigonemodell – that demanded a direct confrontation with the many obstacles brought about by the foreign structure of Greek tragedy as a whole. In turn, such difficulties brought to light the problem of rhythm in its relation to Brecht’s own ideas of how to perform ancient poetry in a modern setting, as exemplified by the originally alienating figure of the tragic chorus. More importantly, such obstacles put into question his ideas of performance in general, as well as the way they can still resonate in our own understanding of what performance is or might be in a broader sense.

  10. A Rhythm-Based Authentication Scheme for Smart Media Devices

    Directory of Open Access Journals (Sweden)

    Jae Dong Lee

    2014-01-01

    Full Text Available In recent years, ubiquitous computing has been rapidly emerged in our lives and extensive studies have been conducted in a variety of areas related to smart devices, such as tablets, smartphones, smart TVs, smart refrigerators, and smart media devices, as a measure for realizing the ubiquitous computing. In particular, smartphones have significantly evolved from the traditional feature phones. Increasingly higher-end smartphone models that can perform a range of functions are now available. Smart devices have become widely popular since they provide high efficiency and great convenience for not only private daily activities but also business endeavors. Rapid advancements have been achieved in smart device technologies to improve the end users’ convenience. Consequently, many people increasingly rely on smart devices to store their valuable and important data. With this increasing dependence, an important aspect that must be addressed is security issues. Leaking of private information or sensitive business data due to loss or theft of smart devices could result in exorbitant damage. To mitigate these security threats, basic embedded locking features are provided in smart devices. However, these locking features are vulnerable. In this paper, an original security-locking scheme using a rhythm-based locking system (RLS is proposed to overcome the existing security problems of smart devices. RLS is a user-authenticated system that addresses vulnerability issues in the existing locking features and provides secure confidentiality in addition to convenience.

  11. A rhythm-based authentication scheme for smart media devices.

    Science.gov (United States)

    Lee, Jae Dong; Jeong, Young-Sik; Park, Jong Hyuk

    2014-01-01

    In recent years, ubiquitous computing has been rapidly emerged in our lives and extensive studies have been conducted in a variety of areas related to smart devices, such as tablets, smartphones, smart TVs, smart refrigerators, and smart media devices, as a measure for realizing the ubiquitous computing. In particular, smartphones have significantly evolved from the traditional feature phones. Increasingly higher-end smartphone models that can perform a range of functions are now available. Smart devices have become widely popular since they provide high efficiency and great convenience for not only private daily activities but also business endeavors. Rapid advancements have been achieved in smart device technologies to improve the end users' convenience. Consequently, many people increasingly rely on smart devices to store their valuable and important data. With this increasing dependence, an important aspect that must be addressed is security issues. Leaking of private information or sensitive business data due to loss or theft of smart devices could result in exorbitant damage. To mitigate these security threats, basic embedded locking features are provided in smart devices. However, these locking features are vulnerable. In this paper, an original security-locking scheme using a rhythm-based locking system (RLS) is proposed to overcome the existing security problems of smart devices. RLS is a user-authenticated system that addresses vulnerability issues in the existing locking features and provides secure confidentiality in addition to convenience.

  12. Circadian Rhythm and Sleep Disruption: Causes, Metabolic Consequences, and Countermeasures.

    Science.gov (United States)

    Potter, Gregory D M; Skene, Debra J; Arendt, Josephine; Cade, Janet E; Grant, Peter J; Hardie, Laura J

    2016-12-01

    Circadian (∼24-hour) timing systems pervade all kingdoms of life and temporally optimize behavior and physiology in humans. Relatively recent changes to our environments, such as the introduction of artificial lighting, can disorganize the circadian system, from the level of the molecular clocks that regulate the timing of cellular activities to the level of synchronization between our daily cycles of behavior and the solar day. Sleep/wake cycles are intertwined with the circadian system, and global trends indicate that these, too, are increasingly subject to disruption. A large proportion of the world's population is at increased risk of environmentally driven circadian rhythm and sleep disruption, and a minority of individuals are also genetically predisposed to circadian misalignment and sleep disorders. The consequences of disruption to the circadian system and sleep are profound and include myriad metabolic ramifications, some of which may be compounded by adverse effects on dietary choices. If not addressed, the deleterious effects of such disruption will continue to cause widespread health problems; therefore, implementation of the numerous behavioral and pharmaceutical interventions that can help restore circadian system alignment and enhance sleep will be important.

  13. Circadian Rhythm and Sleep Disruption: Causes, Metabolic Consequences, and Countermeasures

    Science.gov (United States)

    Skene, Debra J.; Arendt, Josephine; Cade, Janet E.; Grant, Peter J.; Hardie, Laura J.

    2016-01-01

    Circadian (∼24-hour) timing systems pervade all kingdoms of life and temporally optimize behavior and physiology in humans. Relatively recent changes to our environments, such as the introduction of artificial lighting, can disorganize the circadian system, from the level of the molecular clocks that regulate the timing of cellular activities to the level of synchronization between our daily cycles of behavior and the solar day. Sleep/wake cycles are intertwined with the circadian system, and global trends indicate that these, too, are increasingly subject to disruption. A large proportion of the world's population is at increased risk of environmentally driven circadian rhythm and sleep disruption, and a minority of individuals are also genetically predisposed to circadian misalignment and sleep disorders. The consequences of disruption to the circadian system and sleep are profound and include myriad metabolic ramifications, some of which may be compounded by adverse effects on dietary choices. If not addressed, the deleterious effects of such disruption will continue to cause widespread health problems; therefore, implementation of the numerous behavioral and pharmaceutical interventions that can help restore circadian system alignment and enhance sleep will be important. PMID:27763782

  14. Dynamic correlations between heart and brain rhythm during Autogenic meditation

    Directory of Open Access Journals (Sweden)

    Daekeun eKim

    2013-07-01

    Full Text Available This study is aimed to determine significant physiological parameters of brain and heart under meditative state, both in each activities and their dynamic correlations. Electrophysiological changes in response to meditation were explored in 12 healthy volunteers who completed 8 weeks of a basic training course in autogenic meditation. Heart coherence, representing the degree of ordering in oscillation of heart rhythm intervals, increased significantly during meditation. Relative EEG alpha power and alpha lagged coherence also increased. A significant slowing of parietal peak alpha frequency was observed. Parietal peak alpha power increased with increasing heart coherence during meditation, but no such relationship was observed during baseline. Average alpha lagged coherence also increased with increasing heart coherence during meditation, but, again, no significant relationship was observed at baseline. Relative alpha power increased with increasing heart coherence during both meditation and baseline periods. Heart coherence can be a cardiac marker for the meditative state and also may be a general marker for the meditative state since heart coherence is strongly correlated with EEG alpha activities. It is expected that increasing heart coherence and the accompanying EEG alpha activations, heart brain synchronicity, would help recover physiological synchrony following a period of homeostatic depletion.

  15. Dynamic correlations between heart and brain rhythm during Autogenic meditation.

    Science.gov (United States)

    Kim, Dae-Keun; Lee, Kyung-Mi; Kim, Jongwha; Whang, Min-Cheol; Kang, Seung Wan

    2013-01-01

    This study is aimed to determine significant physiological parameters of brain and heart under meditative state, both in each activities and their dynamic correlations. Electrophysiological changes in response to meditation were explored in 12 healthy volunteers who completed 8 weeks of a basic training course in autogenic meditation. Heart coherence, representing the degree of ordering in oscillation of heart rhythm intervals, increased significantly during meditation. Relative EEG alpha power and alpha lagged coherence also increased. A significant slowing of parietal peak alpha frequency was observed. Parietal peak alpha power increased with increasing heart coherence during meditation, but no such relationship was observed during baseline. Average alpha lagged coherence also increased with increasing heart coherence during meditation, but weak opposite relationship was observed at baseline. Relative alpha power increased with increasing heart coherence during both meditation and baseline periods. Heart coherence can be a cardiac marker for the meditative state and also may be a general marker for the meditative state since heart coherence is strongly correlated with EEG alpha activities. It is expected that increasing heart coherence and the accompanying EEG alpha activations, heart brain synchronicity, would help recover physiological synchrony following a period of homeostatic depletion.

  16. Synchronization in human musical rhythms and mutually interacting complex systems.

    Science.gov (United States)

    Hennig, Holger

    2014-09-09

    Though the music produced by an ensemble is influenced by multiple factors, including musical genre, musician skill, and individual interpretation, rhythmic synchronization is at the foundation of musical interaction. Here, we study the statistical nature of the mutual interaction between two humans synchronizing rhythms. We find that the interbeat intervals of both laypeople and professional musicians exhibit scale-free (power law) cross-correlations. Surprisingly, the next beat to be played by one person is dependent on the entire history of the other person's interbeat intervals on timescales up to several minutes. To understand this finding, we propose a general stochastic model for mutually interacting complex systems, which suggests a physiologically motivated explanation for the occurrence of scale-free cross-correlations. We show that the observed long-term memory phenomenon in rhythmic synchronization can be imitated by fractal coupling of separately recorded or synthesized audio tracks and thus applied in electronic music. Though this study provides an understanding of fundamental characteristics of timing and synchronization at the interbrain level, the mutually interacting complex systems model may also be applied to study the dynamics of other complex systems where scale-free cross-correlations have been observed, including econophysics, physiological time series, and collective behavior of animal flocks.

  17. Visible light alters yeast metabolic rhythms by inhibiting respiration.

    Science.gov (United States)

    Robertson, James Brian; Davis, Chris R; Johnson, Carl Hirschie

    2013-12-24

    Exposure of cells to visible light in nature or in fluorescence microscopy often is considered to be relatively innocuous. However, using the yeast respiratory oscillation (YRO) as a sensitive measurement of metabolism, we find that non-UV visible light has a significant impact on yeast metabolism. Blue/green wavelengths of visible light shorten the period and dampen the amplitude of the YRO, which is an ultradian rhythm of cell metabolism and transcription. The wavelengths of light that have the greatest effect coincide with the peak absorption regions of cytochromes. Moreover, treating yeast with the electron transport inhibitor sodium azide has similar effects on the YRO as visible light. Because impairment of respiration by light would change several state variables believed to play vital roles in the YRO (e.g., oxygen tension and ATP levels), we tested oxygen's role in YRO stability and found that externally induced oxygen depletion can reset the phase of the oscillation, demonstrating that respiratory capacity plays a role in the oscillation's period and phase. Light-induced damage to the cytochromes also produces reactive oxygen species that up-regulate the oxidative stress response gene TRX2 that is involved in pathways that enable sustained growth in bright visible light. Therefore, visible light can modulate cellular rhythmicity and metabolism through unexpectedly photosensitive pathways.

  18. An artificial vector model for generating abnormal electrocardiographic rhythms

    International Nuclear Information System (INIS)

    Clifford, Gari D; Nemati, Shamim; Sameni, Reza

    2010-01-01

    We present generalizations of our previously published artificial models for generating multi-channel ECG to provide simulations of abnormal cardiac rhythms. Using a three-dimensional vectorcardiogram (VCG) formulation, we generate the normal cardiac dipole for a patient using a sum of Gaussian kernels, fitted to real VCG recordings. Abnormal beats are specified either as perturbations to the normal dipole or as new dipole trajectories. Switching between normal and abnormal beat types is achieved using a first-order Markov chain. Probability transitions can be learned from real data or modeled by coupling to heart rate and sympathovagal balance. Natural morphology changes from beat-to-beat are incorporated by varying the angular frequency of the dipole as a function of the inter-beat (RR) interval. The RR interval time series is generated using our previously described model whereby time- and frequency-domain heart rate (HR) and heart rate variability characteristics can be specified. QT-HR hysteresis is simulated by coupling the Gaussian kernels associated with the T-wave in the model with a nonlinear factor related to the local HR (determined from the last n RR intervals). Morphology changes due to respiration are simulated by introducing a rotation matrix couple to the respiratory frequency. We demonstrate an example of the use of this model by simulating HR-dependent T-wave alternans (TWA) with and without phase-switching due to ectopy. Application of our model also reveals previously unreported effects of common TWA estimation methods

  19. An analysis of heart rhythm dynamics using a three-coupled oscillator model

    International Nuclear Information System (INIS)

    Gois, Sandra R.F.S.M.; Savi, Marcelo A.

    2009-01-01

    Rhythmic phenomena represent one of the most striking manifestations of the dynamic behavior in biological systems. Understanding the mechanisms responsible for biological rhythms is crucial for the comprehension of the dynamics of life. Natural rhythms could be either regular or irregular over time and space. Each kind of dynamical behavior may be related to both normal and pathological physiological functioning. The cardiac conducting system can be treated as a network of self-excitatory elements and, since these elements exhibit oscillatory behavior, they can be modeled as nonlinear oscillators. This paper proposes a mathematical model to describe heart rhythms considering three modified Van der Pol oscillators connected with time delay couplings. Therefore, the heart dynamics is represented by a system of differential difference equations. Numerical simulations are carried out presenting qualitative agreement with the general heart rhythm behavior. Normal and pathological rhythms represented by the ECG signals are reproduced. Pathological rhythms are generated by either the coupling alterations that represents communications aspects in the heart electric system or forcing excitation representing external pacemaker excitation.

  20. Pineal photoreceptor cells are required for maintaining the circadian rhythms of behavioral visual sensitivity in zebrafish.

    Directory of Open Access Journals (Sweden)

    Xinle Li

    Full Text Available In non-mammalian vertebrates, the pineal gland functions as the central pacemaker that regulates the circadian rhythms of animal behavior and physiology. We generated a transgenic zebrafish line [Tg(Gnat2:gal4-VP16/UAS:nfsB-mCherry] in which the E. coli nitroreductase is expressed in pineal photoreceptor cells. In developing embryos and young adults, the transgene is expressed in both retinal and pineal photoreceptor cells. During aging, the expression of the transgene in retinal photoreceptor cells gradually diminishes. By 8 months of age, the Gnat2 promoter-driven nitroreductase is no longer expressed in retinal photoreceptor cells, but its expression in pineal photoreceptor cells persists. This provides a tool for selective ablation of pineal photoreceptor cells, i.e., by treatments with metronidazole. In the absence of pineal photoreceptor cells, the behavioral visual sensitivity of the fish remains unchanged; however, the circadian rhythms of rod and cone sensitivity are diminished. Brief light exposures restore the circadian rhythms of behavioral visual sensitivity. Together, the data suggest that retinal photoreceptor cells respond to environmental cues and are capable of entraining the circadian rhythms of visual sensitivity; however, they are insufficient for maintaining the rhythms. Cellular signals from the pineal photoreceptor cells may be required for maintaining the circadian rhythms of visual sensitivity.

  1. Alpha-band rhythm suppression during memory recall reflecting memory performance.

    Science.gov (United States)

    Yokosawa, Koichi; Kimura, Keisuke; Chitose, Ryota; Momiki, Takuya; Kuriki, Shinya

    2016-08-01

    Alpha-band rhythm is thought to be involved in memory processes, similarly to other spontaneous brain rhythms. Ten right-handed healthy volunteers participated in our proposed sequential short-term memory task that provides a serial position effect in accuracy rate. We recorded alpha-band rhythms by magnetoencephalography during performance of the task and observed that the amplitude of the rhythm was suppressed dramatically in the memory recall period. The suppressed region was estimated to be in the occipital lobe, suggesting that alpha-band rhythm is suppressed by activation of the occipital attentional network. Additionally, the alpha-band suppression reflected accuracy rate, that is, the amplitude was suppressed more when recalling items with higher accuracy rate. The sensors with a significant correlation between alpha-band amplitude and accuracy rate were located widely from the frontal to occipital regions mainly in the right hemisphere. The results suggests that alpha-band rhythm is involved in memory recall and can be index of memory performance.

  2. Alpha-Band Rhythms in Visual Task Performance: Phase-Locking by Rhythmic Sensory Stimulation

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    de Graaf, Tom A.; Gross, Joachim; Paterson, Gavin; Rusch, Tessa; Sack, Alexander T.; Thut, Gregor

    2013-01-01

    Oscillations are an important aspect of neuronal activity. Interestingly, oscillatory patterns are also observed in behaviour, such as in visual performance measures after the presentation of a brief sensory event in the visual or another modality. These oscillations in visual performance cycle at the typical frequencies of brain rhythms, suggesting that perception may be closely linked to brain oscillations. We here investigated this link for a prominent rhythm of the visual system (the alpha-rhythm, 8–12 Hz) by applying rhythmic visual stimulation at alpha-frequency (10.6 Hz), known to lead to a resonance response in visual areas, and testing its effects on subsequent visual target discrimination. Our data show that rhythmic visual stimulation at 10.6 Hz: 1) has specific behavioral consequences, relative to stimulation at control frequencies (3.9 Hz, 7.1 Hz, 14.2 Hz), and 2) leads to alpha-band oscillations in visual performance measures, that 3) correlate in precise frequency across individuals with resting alpha-rhythms recorded over parieto-occipital areas. The most parsimonious explanation for these three findings is entrainment (phase-locking) of ongoing perceptually relevant alpha-band brain oscillations by rhythmic sensory events. These findings are in line with occipital alpha-oscillations underlying periodicity in visual performance, and suggest that rhythmic stimulation at frequencies of intrinsic brain-rhythms can be used to reveal influences of these rhythms on task performance to study their functional roles. PMID:23555873

  3. Clock Genes and Altered Sleep-Wake Rhythms: Their Role in the Development of Psychiatric Disorders.

    Science.gov (United States)

    Charrier, Annaëlle; Olliac, Bertrand; Roubertoux, Pierre; Tordjman, Sylvie

    2017-04-29

    In mammals, the circadian clocks network (central and peripheral oscillators) controls circadian rhythms and orchestrates the expression of a range of downstream genes, allowing the organism to anticipate and adapt to environmental changes. Beyond their role in circadian rhythms, several studies have highlighted that circadian clock genes may have a more widespread physiological effect on cognition, mood, and reward-related behaviors. Furthermore, single nucleotide polymorphisms in core circadian clock genes have been associated with psychiatric disorders (such as autism spectrum disorder, schizophrenia, anxiety disorders, major depressive disorder, bipolar disorder, and attention deficit hyperactivity disorder). However, the underlying mechanisms of these associations remain to be ascertained and the cause-effect relationships are not clearly established. The objective of this article is to clarify the role of clock genes and altered sleep-wake rhythms in the development of psychiatric disorders (sleep problems are often observed at early onset of psychiatric disorders). First, the molecular mechanisms of circadian rhythms are described. Then, the relationships between disrupted circadian rhythms, including sleep-wake rhythms, and psychiatric disorders are discussed. Further research may open interesting perspectives with promising avenues for early detection and therapeutic intervention in psychiatric disorders.

  4. Shared Components of Rhythm Generation for Locomotion and Scratching Exist Prior to Motoneurons

    Directory of Open Access Journals (Sweden)

    Zhao-Zhe Hao

    2017-08-01

    Full Text Available Does the spinal cord use a single network to generate locomotor and scratching rhythms or two separate networks? Previous research showed that simultaneous swim and scratch stimulation (“dual stimulation” in immobilized, spinal turtles evokes a single rhythm in hindlimb motor nerves with a frequency often greater than during swim stimulation alone or scratch stimulation alone. This suggests that the signals that trigger swimming and scratching converge and are integrated within the spinal cord. However, these results could not determine whether the integration occurs in motoneurons themselves or earlier, in spinal interneurons. Here, we recorded intracellularly from hindlimb motoneurons during dual stimulation. Motoneuron membrane potentials displayed regular oscillations at a higher frequency during dual stimulation than during swim or scratch stimulation alone. In contrast, arithmetic addition of the oscillations during swimming alone and scratching alone with various delays always generated irregular oscillations. Also, the standard deviation of the phase-normalized membrane potential during dual stimulation was similar to those during swimming or scratching alone. In contrast, the standard deviation was greater when pooling cycles of swimming alone and scratching alone for two of the three forms of scratching. This shows that dual stimulation generates a single rhythm prior to motoneurons. Thus, either swimming and scratching largely share a rhythm generator or the two rhythms are integrated into one rhythm by strong interactions among interneurons.

  5. Influence of photoperiod and running wheel access on the entrainment of split circadian rhythms in hamsters

    Directory of Open Access Journals (Sweden)

    Elliott Jeffrey A

    2005-06-01

    Full Text Available Abstract Background In the laboratory, behavioral and physiological states of nocturnal rodents alternate, with a period near 24 h, between those appropriate for the night (e.g., elevated wheel-running activity and high melatonin secretion and for the day (e.g., rest and low melatonin secretion. Under appropriate 24 h light:dark:light:dark conditions, however, rodents may be readily induced to express bimodal rest/activity cycles that reflect a global temporal reorganization of the central neural pacemaker in the hypothalamus. We examine here how the relative length of the light and dark phases of the environmental cycle influences this rhythm splitting and the necessity of a running wheel for expression of this entrainment condition. Results Rhythm splitting was observed in wheel-running and general locomotion of Siberian and Syrian hamsters. The latter also manifest split rhythms in body temperature. Access to a running wheel was necessary neither for the induction nor maintenance of this entrainment pattern. While rhythms were only transiently split in many animals with two 5 h nights, the incidence of splitting was greater with twice daily nights of shorter duration. Removal of running wheels altered the body temperature rhythm but did not eliminate its clear bimodality. Conclusion The expression of entrained, split circadian rhythms exhibits no strict dependence on access to a running wheel, but can be facilitated by manipulation of ambient lighting conditions. These circadian entrainment patterns may be of therapeutic value to human shift-workers and others facing chronobiological challenges.

  6. Seasonal and daily plasma corticosterone rhythms in American toads, Bufo americanus

    International Nuclear Information System (INIS)

    Pancak, M.K.; Taylor, D.H.

    1983-01-01

    Concentrations of corticosterone were measured in the plasma of American toads, Bufo americanus, on a seasonal basis using a radioimmunoassay technique. Two populations of toads, maintained under different light conditions, were monitored to observe the effects of photoperiod on the seasonal rhythm of plasma corticosterone. Under a natural photoperiod toads demonstrated a rhythm consisting of a spring peak and a fall peak in corticosterone concentration. Toads maintained under a 12L:12D photoperiod all year round demonstrated a similar rhythm with peaks in the spring and fall. This suggests that an endogenous (circannual) rhythm of corticosterone may be playing an important role in the seasonal change of overt behavior and physiology of Bufo americanus. A daily rhythm of corticosterone was also detected in toads when blood samples were taken every 4 hr. When compared to a previously published circadian rhythm study of locomotor activity, the surge in corticosterone concentration for the day occurred at 1730 just prior to the peak in locomotor activity

  7. Absence of Circadian Rhythms of Preterm Premature Rupture of Membranes and Preterm Placental Abruption

    Science.gov (United States)

    Luque-Fernandez, Miguel Angel; Ananth, Cande V.; Sanchez, Sixto E.; Qiu, Chun-fang; Hernandez-Diaz, Sonia; Valdimarsdottir, Unnur; Gelaye, Bizu; Williams, Michelle A.

    2014-01-01

    Purpose Data regarding circadian rhythm in the onset of spontaneous preterm premature rupture of membranes (PROM) and placental abruption (PA) cases are conflicting. We modeled the time of onset of preterm PROM and PA cases and examined if the circadian profiles varied based on the gestational age at delivery. Methods We used parametric and nonparametric methods, including trigonometric regression in the framework of generalized linear models, to test the presence of circadian rhythms in the time of onset of preterm PROM and PA cases, among 395 women who delivered a singleton between 2009 and 2010 in Lima, Peru. Results We found a diurnal circadian pattern, with a morning peak at 07h:32’ (95%CI:05h:46’ – 09h:18’) among moderate preterm PROM cases (P-value<0.001), and some evidence of a diurnal circadian periodicity among PA cases in term infants (P-value=0.067). However, we did not find evidence of circadian rhythms in the time of onset of extremely or very preterm PROM (P-value=0.259) and preterm PA (P-value=0.224). Conclusions The circadian rhythms of the time of onset of preterm PROM and PA cases varied based on gestational weeks at delivery. While circadian rhythms were presented among moderate preterm PROM and term PA cases, there was no evidence of circadian rhythms among preterm PA and very or extremely preterm PROM cases, underlying other mechanisms associated with the time of onset. PMID:25453346

  8. Sleep, Rhythms, and the Endocrine Brain: Influence of Sex and Gonadal Hormones

    Science.gov (United States)

    Mong, Jessica A.; Baker, Fiona C.; Mahoney, Megan M.; Paul, Ketema N.; Schwartz, Michael D.; Semba, Kazue; Silver, Rae

    2011-01-01

    While much is known about the mechanisms that underlie sleep and circadian rhythms, the investigation into sex differences and gonadal steroid modulation of sleep and biological rhythms is in its infancy. There is a growing recognition of sex disparities in sleep and rhythm disorders. Understanding how neuroendocrine mediators and sex differences influence sleep and biological rhythms is central to advancing our understanding of sleep-related disorders. While it is known that ovarian steroids affect circadian rhythms in rodents, the role of androgen is less understood. Surprising findings that androgens, acting via androgen receptors in the master “circadian clock” within the suprachiasmatic nucleus (SCN), modulate photic effects on activity in males points to novel mechanisms of circadian control. Work in aromatase deficient (ArKO) mice suggests that some sex differences in photic responsiveness are independent of gonadal hormone effects during development. In parallel, aspects of sex differences in sleep are also reported to be independent of gonadal steroids and may involve sex chromosome complement. This a summary of recent work illustrating how sex differences and gonadal hormones influence sleep and circadian rhythms that was presented at a mini-symposium at the 2011 annual meeting of the Society for Neuroscience. PMID:22072663

  9. Silencing Nicotiana attenuata LHY and ZTL alters circadian rhythms in flowers.

    Science.gov (United States)

    Yon, Felipe; Joo, Youngsung; Cortés Llorca, Lucas; Rothe, Eva; Baldwin, Ian T; Kim, Sang-Gyu

    2016-02-01

    The rhythmic opening/closing and volatile emissions of flowers are known to attract pollinators at specific times. That these rhythms are maintained under constant light or dark conditions suggests a circadian clock involvement. Although a forward and reverse genetic approach has led to the identification of core circadian clock components in Arabidopsis thaliana, the involvement of these clock components in floral rhythms has remained untested, probably because of the weak diurnal rhythms in A. thaliana flowers. Here, we addressed the role of these core clock components in the flowers of the wild tobacco Nicotiana attenuata, whose flowers open at night, emit benzyl acetone (BA) scents and move vertically through a 140° arc. We first measured N. attenuata floral rhythms under constant light conditions. The results suggest that the circadian clock controls flower opening, BA emission and pedicel movement, but not flower closing. We generated transgenic N. attenuata lines silenced in the homologous genes of Arabidopsis LATE ELONGATED HYPOCOTYL (LHY) and ZEITLUPE (ZTL), which are known to be core clock components. Silencing NaLHY and NaZTL strongly altered floral rhythms in different ways, indicating that conserved clock components in N. attenuata coordinate these floral rhythms. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  10. The daily rhythm of body temperature, heart and respiratory rate in newborn dogs.

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    Piccione, Giuseppe; Giudice, Elisabetta; Fazio, Francesco; Mortola, Jacopo P

    2010-08-01

    We asked whether, during the postnatal period, the daily patterns of body temperature (Tb), heart rate (HR) and breathing frequency (f) begin and develop in synchrony. To this end, measurements of HR, f and Tb were performed weekly, on two consecutive days, for the first two postnatal months on puppies of three breeds of dogs (Rottweiler, Cocker Spaniel and Carlino dogs) with very different birth weights and postnatal growth patterns. Ambient conditions and feeding habits were constant for all puppies. The results indicated that (1) the 24-h average Tb increased and average HR and f decreased with growth, (2) the daily rhythms in Tb were apparent by 4 weeks, irrespective of the puppy's growth pattern, (3) the daily rhythm of Tb in the puppy was not necessarily following that of the mother; in fact, it could anticipate it. (4) The daily rhythms in HR and f were not apparent for the whole study period. We conclude that in neonatal dogs the onset of the daily rhythms of Tb has no obvious relationship with body size or rate of growth and is not cued by the maternal Tb rhythm. The daily rhythms of HR and f do not appear before 2 months of age. Hence, they are not in synchrony with those of Tb.

  11. Clock Genes and Altered Sleep–Wake Rhythms: Their Role in the Development of Psychiatric Disorders

    Directory of Open Access Journals (Sweden)

    Annaëlle Charrier

    2017-04-01

    Full Text Available In mammals, the circadian clocks network (central and peripheral oscillators controls circadian rhythms and orchestrates the expression of a range of downstream genes, allowing the organism to anticipate and adapt to environmental changes. Beyond their role in circadian rhythms, several studies have highlighted that circadian clock genes may have a more widespread physiological effect on cognition, mood, and reward-related behaviors. Furthermore, single nucleotide polymorphisms in core circadian clock genes have been associated with psychiatric disorders (such as autism spectrum disorder, schizophrenia, anxiety disorders, major depressive disorder, bipolar disorder, and attention deficit hyperactivity disorder. However, the underlying mechanisms of these associations remain to be ascertained and the cause–effect relationships are not clearly established. The objective of this article is to clarify the role of clock genes and altered sleep–wake rhythms in the development of psychiatric disorders (sleep problems are often observed at early onset of psychiatric disorders. First, the molecular mechanisms of circadian rhythms are described. Then, the relationships between disrupted circadian rhythms, including sleep–wake rhythms, and psychiatric disorders are discussed. Further research may open interesting perspectives with promising avenues for early detection and therapeutic intervention in psychiatric disorders.

  12. Adrenal, thyroid, and testicular hormone rhythms in male golden hamsters on long and short days

    International Nuclear Information System (INIS)

    Ottenweller, J.E.; Tapp, W.N.; Pitman, D.L.; Natelson, B.H.

    1987-01-01

    Plasma concentrations of adrenal, thyroid, and testicular hormones were measured at 4-h intervals around the clock in male hamsters on long (14:10-h light-dark cycle) and short (10:14-h light-dark cycle) days. Plasma corticosterone, cortisol, thyroxine (T 4 ), triiodothyronine (T 3 ), and testosterone rhythms were present on long days. The only one of these hormones to have a significant rhythm on short days was cortisol, but even its amplitude was suppressed compared with the cortisol rhythm on long days. Short days also lowered mean plasma levels of cortisol, T 4 , T 3 , and testosterone. Finally, short days raised the ratio of corticosterone to cortisol and lowered the ratio of T 4 to T 3 . Both ratios had significant rhythms on long days but not on short days. Because of the many interactions among adrenal, thyroid, and testicular hormone axes, it is unclear whether the primary effect of short days is on one of these endocrine systems or on another factor that has separate effects on each of the hormone rhythms that was measured. Nonetheless, it is clear that a major effect of short day lengths in hamsters is to suppress hormone rhythms. Explanations of photoperiodic effects that depend on endocrine mediation should take this into account

  13. Estimation of Circadian Body Temperature Rhythm Based on Heart Rate in Healthy, Ambulatory Subjects.

    Science.gov (United States)

    Sim, Soo Young; Joo, Kwang Min; Kim, Han Byul; Jang, Seungjin; Kim, Beomoh; Hong, Seungbum; Kim, Sungwan; Park, Kwang Suk

    2017-03-01

    Core body temperature is a reliable marker for circadian rhythm. As characteristics of the circadian body temperature rhythm change during diverse health problems, such as sleep disorder and depression, body temperature monitoring is often used in clinical diagnosis and treatment. However, the use of current thermometers in circadian rhythm monitoring is impractical in daily life. As heart rate is a physiological signal relevant to thermoregulation, we investigated the feasibility of heart rate monitoring in estimating circadian body temperature rhythm. Various heart rate parameters and core body temperature were simultaneously acquired in 21 healthy, ambulatory subjects during their routine life. The performance of regression analysis and the extended Kalman filter on daily body temperature and circadian indicator (mesor, amplitude, and acrophase) estimation were evaluated. For daily body temperature estimation, mean R-R interval (RRI), mean heart rate (MHR), or normalized MHR provided a mean root mean square error of approximately 0.40 °C in both techniques. The mesor estimation regression analysis showed better performance than the extended Kalman filter. However, the extended Kalman filter, combined with RRI or MHR, provided better accuracy in terms of amplitude and acrophase estimation. We suggest that this noninvasive and convenient method for estimating the circadian body temperature rhythm could reduce discomfort during body temperature monitoring in daily life. This, in turn, could facilitate more clinical studies based on circadian body temperature rhythm.

  14. On Rhythms in Neuronal Networks with Recurrent Excitation.

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    Börgers, Christoph; Takeuchi, R Melody; Rosebrock, Daniel T

    2018-02-01

    We investigate rhythms in networks of neurons with recurrent excitation, that is, with excitatory cells exciting each other. Recurrent excitation can sustain activity even when the cells in the network are driven below threshold, too weak to fire on their own. This sort of "reverberating" activity is often thought to be the basis of working memory. Recurrent excitation can also lead to "runaway" transitions, sudden transitions to high-frequency firing; this may be related to epileptic seizures. Not all fundamental questions about these phenomena have been answered with clarity in the literature. We focus on three questions here: (1) How much recurrent excitation is needed to sustain reverberating activity? How does the answer depend on parameters? (2) Is there a positive minimum frequency of reverberating activity, a positive "onset frequency"? How does it depend on parameters? (3) When do runaway transitions occur? For reduced models, we give mathematical answers to these questions. We also examine computationally to which extent our findings are reflected in the behavior of biophysically more realistic model networks. Our main results can be summarized as follows. (1) Reverberating activity can be fueled by extremely weak slow recurrent excitation, but only by sufficiently strong fast recurrent excitation. (2) The onset of reverberating activity, as recurrent excitation is strengthened or external drive is raised, occurs at a positive frequency. It is faster when the external drive is weaker (and the recurrent excitation stronger). It is slower when the recurrent excitation has a longer decay time constant. (3) Runaway transitions occur only with fast, not with slow, recurrent excitation. We also demonstrate that the relation between reverberating activity fueled by recurrent excitation and runaway transitions can be visualized in an instructive way by a (generalized) cusp catastrophe surface.

  15. Cardiorespiratory Coupling: Common Rhythms in Cardiac, Sympathetic, and Respiratory Activities

    Science.gov (United States)

    Dick, Thomas E.; Hsieh, Yee-Hsee; Dhingra, Rishi R.; Baekey, David M.; Galán, Roberto F.; Wehrwein, Erica; Morris, Kendall F.

    2014-01-01

    purpose for cardiorespiratory coupling is the biggest barrier for recognizing its significance. Cardiorespiratory coupling has only a small effect on the efficiency of gas exchange; rather, we propose that cardiorespiratory control system may act as weakly coupled oscillator to maintain rhythms within a bounded variability. PMID:24746049

  16. Scapulohumeral rhythm in shoulders with reverse shoulder arthroplasty.

    Science.gov (United States)

    Walker, David; Matsuki, Keisuke; Struk, Aimee M; Wright, Thomas W; Banks, Scott A

    2015-07-01

    Little is known about kinematic function of reverse total shoulder arthroplasty (RTSA). Scapulohumeral rhythm (SHR) is a common metric for assessing muscle function and shoulder joint motion. The purpose of this study was to compare SHR in shoulders with RTSA to normal shoulders. Twenty-eight subjects, more than 12 months after unilateral RTSA, were recruited for an Institutional Review Board-approved study. Subjects performed arm abduction in the coronal plane with and without a 1.4-kg hand-held weight. Three-dimensional model-image registration techniques were used to measure orientation and position for the humerus and scapula from fluoroscopic images. Analysis of variance and Tukey tests were used to assess groupwise and pairwise differences. SHR in RTSA shoulders (1.3:1) was significantly lower than in normal shoulders (3:1). Below 30° abduction, RTSA and normal shoulders show a wide range of SHR (1.3:1 to 17:1). Above 30° abduction, SHR in RTSA shoulders was 1.3:1 for unweighted abduction and 1.3:1 for weighted abduction. Maximum RTSA shoulder abduction in weighted trials was lower than in unweighted trials. SHR variability in RTSA shoulders decreased with increasing arm elevation. RTSA shoulders show kinematics that are significantly different from normal shoulders. SHR in RTSA shoulders was significantly lower than in normal shoulders, indicating that RTSA shoulders use more scapulothoracic motion and less glenohumeral motion to elevate the arm. With these observations, it may be possible to improve rehabilitation protocols, with particular attention to the periscapular muscles, and implant design or placement to optimize functional outcomes in shoulders with RTSA. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  17. Spatial distribution of conduction disorders during sinus rhythm.

    Science.gov (United States)

    Lanters, Eva A H; Yaksh, Ameeta; Teuwen, Christophe P; van der Does, Lisette J M E; Kik, Charles; Knops, Paul; van Marion, Denise M S; Brundel, Bianca J J M; Bogers, Ad J J C; Allessie, Maurits A; de Groot, Natasja M S

    2017-12-15

    Length of lines of conduction block (CB) during sinus rhythm (SR) at Bachmann's bundle (BB) is associated with atrial fibrillation (AF). However, it is unknown whether extensiveness of CB at BB represents CB elsewhere in the atria. We aim to investigate during SR 1) the spatial distribution and extensiveness of CB 2) whether there is a predilection site for CB and 3) the association between CB and incidence of post-operative AF. During SR, epicardial mapping of the right atrium (RA), BB and left atrium was performed in 209 patients with coronary artery disease. The amount of conduction delay (CD, Δlocal activation time ≥7ms) and CB (Δ≥12ms) was quantified as % of the mapping area. Atrial regions were compared to identify potential predilection sites for CD/CB. Correlations between CD/CB and clinical characteristics were tested. Areas with CD or CB were present in all patients, overall prevalence was respectively 1.4(0.2-4.0) % and 1.3(0.1-4.3) %. Extensiveness and spatial distribution of CD/CB varied considerably, however occurred mainly at the superior intercaval RA. Of all clinicalcharacteristics, CD/CB only correlated weakly with age and diabetes (P<0.05). A 1% increase in CD or CB caused a 1.1-1.5ms prolongation of the activation time (P<0.001). There was no correlation between CD/CB and post-operative AF. CD/CB during SR in CABG patients with electrically non-remodeled atria show considerable intra-atrial, but also inter-individual variation. Despite these differences, a predilection site is present at the superior intercaval RA. Extensiveness of CB at the superior intercaval RA or BB does not reflect CB elsewhere in the atria and is not associated with post-operative AF. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. What time is it? Deep learning approaches for circadian rhythms.

    Science.gov (United States)

    Agostinelli, Forest; Ceglia, Nicholas; Shahbaba, Babak; Sassone-Corsi, Paolo; Baldi, Pierre

    2016-06-15

    Circadian rhythms date back to the origins of life, are found in virtually every species and every cell, and play fundamental roles in functions ranging from metabolism to cognition. Modern high-throughput technologies allow the measurement of concentrations of transcripts, metabolites and other species along the circadian cycle creating novel computational challenges and opportunities, including the problems of inferring whether a given species oscillate in circadian fashion or not, and inferring the time at which a set of measurements was taken. We first curate several large synthetic and biological time series datasets containing labels for both periodic and aperiodic signals. We then use deep learning methods to develop and train BIO_CYCLE, a system to robustly estimate which signals are periodic in high-throughput circadian experiments, producing estimates of amplitudes, periods, phases, as well as several statistical significance measures. Using the curated data, BIO_CYCLE is compared to other approaches and shown to achieve state-of-the-art performance across multiple metrics. We then use deep learning methods to develop and train BIO_CLOCK to robustly estimate the time at which a particular single-time-point transcriptomic experiment was carried. In most cases, BIO_CLOCK can reliably predict time, within approximately 1 h, using the expression levels of only a small number of core clock genes. BIO_CLOCK is shown to work reasonably well across tissue types, and often with only small degradation across conditions. BIO_CLOCK is used to annotate most mouse experiments found in the GEO database with an inferred time stamp. All data and software are publicly available on the CircadiOmics web portal: circadiomics.igb.uci.edu/ fagostin@uci.edu or pfbaldi@uci.edu Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

  19. Basal ganglia and cortical networks for sequential ordering and rhythm of complex movements

    Directory of Open Access Journals (Sweden)

    Jeffery G. Bednark

    2015-07-01

    Full Text Available Voluntary actions require the concurrent engagement and coordinated control of complex temporal (e.g. rhythm and ordinal motor processes. Using high-resolution functional magnetic resonance imaging (fMRI and multi-voxel pattern analysis (MVPA, we sought to determine the degree to which these complex motor processes are dissociable in basal ganglia and cortical networks. We employed three different finger-tapping tasks that differed in the demand on the sequential temporal rhythm or sequential ordering of submovements. Our results demonstrate that sequential rhythm and sequential order tasks were partially dissociable based on activation differences. The sequential rhythm task activated a widespread network centered around the SMA and basal-ganglia regions including the dorsomedial putamen and caudate nucleus, while the sequential order task preferentially activated a fronto-parietal network. There was also extensive overlap between sequential rhythm and sequential order tasks, with both tasks commonly activating bilateral premotor, supplementary motor, and superior/inferior parietal cortical regions, as well as regions of the caudate/putamen of the basal ganglia and the ventro-lateral thalamus. Importantly, within the cortical regions that were active for both complex movements, MVPA could accurately classify different patterns of activation for the sequential rhythm and sequential order tasks. In the basal ganglia, however, overlapping activation for the sequential rhythm and sequential order tasks, which was found in classic motor circuits of the putamen and ventro-lateral thalamus, could not be accurately differentiated by MVPA. Overall, our results highlight the convergent architecture of the motor system, where complex motor information that is spatially distributed in the cortex converges into a more compact representation in the basal ganglia.

  20. Sustained Accelerated Idioventricular Rhythm in a Centrifuge-Simulated Suborbital Spaceflight.

    Science.gov (United States)

    Suresh, Rahul; Blue, Rebecca S; Mathers, Charles; Castleberry, Tarah L; Vanderploeg, James M

    2017-08-01

    Hypergravitational exposures during human centrifugation are known to provoke dysrhythmias, including sinus dysrhythmias/tachycardias, premature atrial/ventricular contractions, and even atrial fibrillations or flutter patterns. However, events are generally short-lived and resolve rapidly after cessation of acceleration. This case report describes a prolonged ectopic ventricular rhythm in response to high G exposure. A previously healthy 30-yr-old man voluntarily participated in centrifuge trials as a part of a larger study, experiencing a total of 7 centrifuge runs over 48 h. Day 1 consisted of two +Gz runs (peak +3.5 Gz, run 2) and two +Gx runs (peak +6.0 Gx, run 4). Day 2 consisted of three runs approximating suborbital spaceflight profiles (combined +Gx and +Gz). Hemodynamic data collected included blood pressure, heart rate, and continuous three-lead electrocardiogram. Following the final acceleration exposure of the last Day 2 run (peak +4.5 Gx and +4.0 Gz combined, resultant +6.0 G), during a period of idle resting centrifuge activity (resultant vector +1.4 G), the subject demonstrated a marked change in his three-lead electrocardiogram from normal sinus rhythm to a wide-complex ectopic ventricular rhythm at a rate of 91-95 bpm, consistent with an accelerated idioventricular rhythm (AIVR). This rhythm was sustained for 2 m, 24 s before reversion to normal sinus. The subject reported no adverse symptoms during this time. While prolonged, the dysrhythmia was asymptomatic and self-limited. AIVR is likely a physiological response to acceleration and can be managed conservatively. Vigilance is needed to ensure that AIVR is correctly distinguished from other, malignant rhythms to avoid inappropriate treatment and negative operational impacts.Suresh R, Blue RS, Mathers C, Castleberry TL, Vanderploeg JM. Sustained accelerated idioventricular rhythm in a centrifuge-simulated suborbital spaceflight. Aerosp Med Hum Perform. 2017; 88(8):789-793.

  1. Timing of food intake impacts daily rhythms of human salivary microbiota: a randomized, crossover study.

    Science.gov (United States)

    Collado, María Carmen; Engen, Phillip A; Bandín, Cristina; Cabrera-Rubio, Raúl; Voigt, Robin M; Green, Stefan J; Naqib, Ankur; Keshavarzian, Ali; Scheer, Frank A J L; Garaulet, Marta

    2018-04-01

    The composition of the diet (what we eat) has been widely related to the microbiota profile. However, whether the timing of food consumption (when we eat) influences microbiota in humans is unknown. A randomized, crossover study was performed in 10 healthy normal-weight young women to test the effect of the timing of food intake on the human microbiota in the saliva and fecal samples. More specifically, to determine whether eating late alters daily rhythms of human salivary microbiota, we interrogated salivary microbiota in samples obtained at 4 specific time points over 24 h, to achieve a better understanding of the relationship between food timing and metabolic alterations in humans. Results revealed significant diurnal rhythms in salivary diversity and bacterial relative abundance ( i.e., TM7 and Fusobacteria) across both early and late eating conditions. More importantly, meal timing affected diurnal rhythms in diversity of salivary microbiota toward an inverted rhythm between the eating conditions, and eating late increased the number of putative proinflammatory taxa, showing a diurnal rhythm in the saliva. In a randomized, crossover study, we showed for the first time the impact of the timing of food intake on human salivary microbiota. Eating the main meal late inverts the daily rhythm of salivary microbiota diversity which may have a deleterious effect on the metabolism of the host.-Collado, M. C., Engen, P. A., Bandín, C., Cabrera-Rubio, R., Voigt, R. M., Green, S. J., Naqib, A., Keshavarzian, A., Scheer, F. A. J. L., Garaulet, M. Timing of food intake impacts daily rhythms of human salivary microbiota: a randomized, crossover study.

  2. A riot of rhythms: neuronal and glial circadian oscillators in the mediobasal hypothalamus

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    Guilding Clare

    2009-08-01

    Full Text Available Abstract Background In mammals, the synchronized activity of cell autonomous clocks in the suprachiasmatic nuclei (SCN enables this structure to function as the master circadian clock, coordinating daily rhythms in physiology and behavior. However, the dominance of this clock has been challenged by the observations that metabolic duress can over-ride SCN controlled rhythms, and that clock genes are expressed in many brain areas, including those implicated in the regulation of appetite and feeding. The recent development of mice in which clock gene/protein activity is reported by bioluminescent constructs (luciferase or luc now enables us to track molecular oscillations in numerous tissues ex vivo. Consequently we determined both clock activities and responsiveness to metabolic perturbations of cells and tissues within the mediobasal hypothalamus (MBH, a site pivotal for optimal internal homeostatic regulation. Results Here we demonstrate endogenous circadian rhythms of PER2::LUC expression in discrete subdivisions of the arcuate (Arc and dorsomedial nuclei (DMH. Rhythms resolved to single cells did not maintain long-term synchrony with one-another, leading to a damping of oscillations at both cell and tissue levels. Complementary electrophysiology recordings revealed rhythms in neuronal activity in the Arc and DMH. Further, PER2::LUC rhythms were detected in the ependymal layer of the third ventricle and in the median eminence/pars tuberalis (ME/PT. A high-fat diet had no effect on the molecular oscillations in the MBH, whereas food deprivation resulted in an altered phase in the ME/PT. Conclusion Our results provide the first single cell resolution of endogenous circadian rhythms in clock gene expression in any intact tissue outside the SCN, reveal the cellular basis for tissue level damping in extra-SCN oscillators and demonstrate that an oscillator in the ME/PT is responsive to changes in metabolism.

  3. Circadian Rhythm of Glomerular Filtration and Solute Handling Related to Nocturnal Enuresis.

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    Dossche, L; Raes, A; Hoebeke, P; De Bruyne, P; Vande Walle, J

    2016-01-01

    Although nocturnal polyuria in patients with monosymptomatic enuresis can largely be explained by the decreased nocturnal vasopressin secretion hypothesis, other circadian rhythms in the kidney also seem to have a role. We recently documented an absent day/night rhythm in a subgroup of desmopressin refractory cases. We explore the importance of abnormal circadian rhythm of glomerular filtration and tubular (sodium, potassium) parameters in patients with monosymptomatic enuresis. In this retrospective study of a tertiary enuresis population we collected data subsequent to a standardized screening (International Children's Continence Society questionnaire), 14-day diary for nocturnal enuresis and diuresis, and 24-hour concentration profile. The study population consisted of 139 children with nocturnal enuresis who were 5 years or older. Children with nonmonosymptomatic nocturnal enuresis were used as controls. There was a maintained circadian rhythm of glomerular filtration, sodium, osmotic excretion and diuresis rate in children with monosymptomatic and nonmonosymptomatic nocturnal enuresis, and there was no difference between the 2 groups. Secondary analysis revealed that in patients with nocturnal polyuria (with monosymptomatic or nonmonosymptomatic nocturnal enuresis) circadian rhythm of glomerular filtration, sodium and osmotic excretion, and diuresis rate was diminished in contrast to those without nocturnal polyuria (p Circadian rhythm of the kidney does not differ between patients with nonmonosymptomatic and monosymptomatic enuresis. However, the subgroup with enuresis and nocturnal polyuria has a diminished circadian rhythm of nocturnal diuresis, sodium excretion and glomerular filtration in contrast to children without nocturnal polyuria. This observation cannot be explained by the vasopressin theory alone. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  4. Maternal exercise, season and sex modify the human fetal circadian rhythm.

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    Sletten, Julie; Cornelissen, Germaine; Assmus, Jørg; Kiserud, Torvid; Albrechtsen, Susanne; Kessler, Jörg

    2018-05-13

    The knowledge on circadian rhythmicity is rapidly expanding. We aimed to define the longitudinal development of the circadian heart rate rhythm in the human fetus in an unrestricted, out-of-hospital setting, and to examine the effects of maternal physical activity, season and fetal sex. We recruited 48 women with low-risk singleton pregnancies. Using a portable monitor for continuous fetal electrocardiography, fetal heart rate recordings were obtained around gestational weeks 24, 28, 32 and 36. Circadian rhythmicity in fetal heart rate and fetal heart rate variation was detected by cosinor analysis; developmental trends were calculated by population-mean cosinor and multilevel analysis. For the fetal heart rate and fetal heart rate variation, a significant circadian rhythm was present in 122/123 (99.2%) and 116/121 (95.9%) of the individual recordings, respectively. The rhythms were best described by combining cosine waves with periods of 24 and 8 hours. With increasing gestational age, the magnitude of the fetal heart rate rhythm increased, and the peak of the fetal heart rate variation rhythm shifted from a mean of 14:25 (24 weeks) to 20:52 (36 weeks). With advancing gestation, the rhythm-adjusted mean value of the fetal heart rate decreased linearly in females (prhythm diversity was found in male fetuses, during higher maternal physical activity and during the summer season. The dynamic development of the fetal circadian heart rate rhythm during the second half of pregnancy is modified by fetal sex, maternal physical activity and season. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  5. Development of Salivary Cortisol Circadian Rhythm and Reference Intervals in Full-Term Infants.

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    Ivars, Katrin; Nelson, Nina; Theodorsson, Annette; Theodorsson, Elvar; Ström, Jakob O; Mörelius, Evalotte

    2015-01-01

    Cortisol concentrations in plasma display a circadian rhythm in adults and children older than one year. Earlier studies report divergent results regarding when cortisol circadian rhythm is established. The present study aims to investigate at what age infants develop a circadian rhythm, as well as the possible influences of behavioral regularity and daily life trauma on when the rhythm is established. Furthermore, we determine age-related reference intervals for cortisol concentrations in saliva during the first year of life. 130 healthy full-term infants were included in a prospective, longitudinal study with saliva sampling on two consecutive days, in the morning (07:30-09:30), noon (10:00-12:00) and evening (19:30-21:30), each month from birth until the infant was twelve months old. Information about development of behavioral regularity and potential exposure to trauma was obtained from the parents through the Baby Behavior Questionnaire and the Life Incidence of Traumatic Events checklist. A significant group-level circadian rhythm of salivary cortisol secretion was established at one month, and remained throughout the first year of life, although there was considerable individual variability. No correlation was found between development of cortisol circadian rhythm and the results from either the Baby Behavior Questionnaire or the Life Incidence of Traumatic Events checklist. The study presents salivary cortisol reference intervals for infants during the first twelve months of life. Cortisol circadian rhythm in infants is already established by one month of age, earlier than previous studies have shown. The current study also provides first year age-related reference intervals for salivary cortisol levels in healthy, full-term infants.

  6. Melanopsin resets circadian rhythms in cells by inducing clock gene Period1

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    Yamashita, Shuhei; Uehara, Tomoe; Matsuo, Minako; Kikuchi, Yo; Numano, Rika

    2014-02-01

    The biochemical, physiological and behavioral processes are under the control of internal clocks with the period of approximately 24 hr, circadian rhythms. The expression of clock gene Period1 (Per1) oscillates autonomously in cells and is induced immediately after a light pulse. Per1 is an indispensable member of the central clock system to maintain the autonomous oscillator and synchronize environmental light cycle. Per1 expression could be detected by Per1∷luc and Per1∷GFP plasmid DNA in which firefly luciferase and Green Fluorescence Protein were rhythmically expressed under the control of the mouse Per1 promoter in order to monitor mammalian circadian rhythms. Membrane protein, MELANOPSIN is activated by blue light in the morning on the retina and lead to signals transduction to induce Per1 expression and to reset the phase of circadian rhythms. In this report Per1 induction was measured by reporter signal assay in Per1∷luc and Per1∷GFP fibroblast cell at the input process of circadian rhythms. To the result all process to reset the rhythms by Melanopsin is completed in single cell like in the retina projected to the central clock in the brain. Moreover, the phase of circadian rhythm in Per1∷luc cells is synchronized by photo-activated Melanopsin, because the definite peak of luciferase activity in one dish was found one day after light illumination. That is an available means that physiological circadian rhythms could be real-time monitor as calculable reporter (bioluminescent and fluorescent) chronological signal in both single and groups of cells.

  7. Thalamic gap junctions control local neuronal synchrony and influence macroscopic oscillation amplitude during EEG alpha rhythms

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    Stuart eHughes

    2011-08-01

    Full Text Available Although EEG alpha ( (8-13 Hz rhythms are often considered to reflect an ‘idling’ brain state, numerous studies indicate that they are also related to many aspects of perception. Recently, we outlined a potential cellular substrate by which such aspects of perception might be linked to basic  rhythm mechanisms. This scheme relies on a specialized subset of rhythmically bursting thalamocortical (TC neurons (high-threshold bursting cells in the lateral geniculate nucleus (LGN which are interconnected by gap junctions (GJs. By engaging GABAergic interneurons, that in turn inhibit conventional relay-mode TC neurons, these cells can lead to an effective temporal framing of thalamic relay-mode output. Although the role of GJs is pivotal in this scheme, evidence for their involvement in thalamic  rhythms has thus far mainly derived from experiments in in vitro slice preparations. In addition, direct anatomical evidence of neuronal GJs in the LGN is currently lacking. To address the first of these issues we tested the effects of the GJ inhibitors, carbenoxolone (CBX and 18-glycyrrhetinic acid (18-GA, given directly to the LGN via reverse microdialysis, on spontaneous LGN and EEG  rhythms in behaving cats. We also examined the effect of CBX on  rhythm-related LGN unit activity. Indicative of a role for thalamic GJs in these activities, 18-GA and CBX reversibly suppressed both LGN and EEG  rhythms, with CBX also decreasing neuronal synchrony. To address the second point, we used electron microscopy to obtain definitive ultrastructural evidence for the presence of GJs between neurons in the cat LGN. As interneurons show no phenotypic evidence of GJ coupling (i.e. dye-coupling and spikelets we conclude that these GJs must belong to TC neurons. The potential significance of these findings for relating macroscopic changes in  rhythms to basic cellular processes is discussed.

  8. Nocturnal polyuria is related to absent circadian rhythm of glomerular filtration rate.

    Science.gov (United States)

    De Guchtenaere, A; Vande Walle, C; Van Sintjan, P; Raes, A; Donckerwolcke, R; Van Laecke, E; Hoebeke, P; Vande Walle, J

    2007-12-01

    Monosymptomatic nocturnal enuresis is frequently associated with nocturnal polyuria and low urinary osmolality during the night. Initial studies found decreased vasopressin levels associated with low urinary osmolality overnight. Together with the documented desmopressin response, this was suggestive of a primary role for vasopressin in the pathogenesis of enuresis in the absence of bladder dysfunction. Recent studies no longer confirm this primary role of vasopressin. Other pathogenetic factors such as disordered renal sodium handling, hypercalciuria, increased prostaglandins and/or osmotic excretion might have a role. So far, little attention has been given to abnormalities in the circadian rhythm of glomerular filtration rate. We evaluated the circadian rhythm of glomerular filtration rate and diuresis in children with desmopressin resistant monosymptomatic nocturnal enuresis and nocturnal polyuria. We evaluated 15 children (9 boys) 9 to 14 years old with monosymptomatic nocturnal enuresis and nocturnal polyuria resistant to desmopressin treatment. The control group consisted of 25 children (12 boys) 9 to 16 years old with monosymptomatic nocturnal enuresis without nocturnal polyuria. Compared to the control population, children with nocturnal polyuria lost their circadian rhythm not only for diuresis and sodium excretion but also for glomerular filtration rate. Patients with monosymptomatic nocturnal enuresis and nocturnal polyuria lack a normal circadian rhythm for diuresis and sodium excretion, and the circadian rhythm of glomerular filtration rate is absent. This absence of circadian rhythm of glomerular filtration rate and/or sodium handling cannot be explained by a primary role of vasopressin, but rather by a disorder in circadian rhythm of renal glomerular and/or tubular functions.

  9. Development of a Low-cost, Comprehensive Recording System for Circadian Rhythm Behavior.

    Science.gov (United States)

    Kwon, Jea; Park, Min Gu; Lee, Seung Eun; Lee, C Justin

    2018-02-01

    Circadian rhythm is defined as a 24-hour biological oscillation, which persists even without any external cues but also can be re-entrained by various environmental cues. One of the widely accepted circadian rhythm behavioral experiment is measuring the wheel-running activity (WRA) of rodents. However, the price for commercially available WRA recording system is not easily affordable for researchers due to high-cost implementation of sensors for wheel rotation. Here, we developed a cost-effective and comprehensive system for circadian rhythm recording by measuring the house-keeping activities (HKA). We have monitored animal's HKA as electrical signal by simply connecting animal housing cage with a standard analog/digital converter: input to the metal lid and ground to the metal grid floor. We show that acquired electrical signals are combined activities of eating, drinking and natural locomotor behaviors which are well-known indicators of circadian rhythm. Post-processing of measured electrical signals enabled us to draw actogram, which verifies HKA to be reliable circadian rhythm indicator. To provide easy access of HKA recording system for researchers, we have developed user-friendly MATLAB-based software, Circa Analysis. This software provides functions for easy extraction of scalable "touch activity" from raw data files by automating seven steps of post-processing and drawing actograms with highly intuitive user-interface and various options. With our cost-effective HKA circadian rhythm recording system, we have estimated the cost of our system to be less than $150 per channel. We anticipate our system will benefit many researchers who would like to study circadian rhythm.

  10. Rhythmic complexity and predictive coding: a novel approach to modeling rhythm and meter perception in music

    Science.gov (United States)

    Vuust, Peter; Witek, Maria A. G.

    2014-01-01

    Musical rhythm, consisting of apparently abstract intervals of accented temporal events, has a remarkable capacity to move our minds and bodies. How does the cognitive system enable our experiences of rhythmically complex music? In this paper, we describe some common forms of rhythmic complexity in music and propose the theory of predictive coding (PC) as a framework for understanding how rhythm and rhythmic complexity are processed in the brain. We also consider why we feel so compelled by rhythmic tension in music. First, we consider theories of rhythm and meter perception, which provide hierarchical and computational approaches to modeling. Second, we present the theory of PC, which posits a hierarchical organization of brain responses reflecting fundamental, survival-related mechanisms associated with predicting future events. According to this theory, perception and learning is manifested through the brain’s Bayesian minimization of the error between the input to the brain and the brain’s prior expectations. Third, we develop a PC model of musical rhythm, in which rhythm perception is conceptualized as an interaction between what is heard (“rhythm”) and the brain’s anticipatory structuring of music (“meter”). Finally, we review empirical studies of the neural and behavioral effects of syncopation, polyrhythm and groove, and propose how these studies can be seen as special cases of the PC theory. We argue that musical rhythm exploits the brain’s general principles of prediction and propose that pleasure and desire for sensorimotor synchronization from musical rhythm may be a result of such mechanisms. PMID:25324813

  11. Rhythmic complexity and predictive coding: A novel approach to modeling rhythm and meter perception in music

    Directory of Open Access Journals (Sweden)

    Peter eVuust

    2014-10-01

    Full Text Available Musical rhythm, consisting of apparently abstract intervals of accented temporal events, has a remarkable capacity to move our minds and bodies. How does the cognitive system enable our experiences of rhythmically complex music? In this paper, we describe some common forms of rhythmic complexity in music and propose the theory of predictive coding as a framework for understanding how rhythm and rhythmic complexity are processed in the brain. We also consider why we feel so compelled by rhythmic tension in music. First, we consider theories of rhythm and meter perception, which provide hierarchical and computational approaches to modeling. Second, we present the theory of predictive coding, which posits a hierarchical organization of brain responses reflecting fundamental, survival-related mechanisms associated with predicting future events. According to this theory, perception and learning is manifested through the brain’s Bayesian minimization of the error between the input to the brain and the brain’s prior expectations. Third, we develop a predictive coding model of musical rhythm, in which rhythm perception is conceptualized as an interaction between what is heard (‘rhythm’ and the brain’s anticipatory structuring of music (‘meter’. Finally, we review empirical studies of the neural and behavioral effects of syncopation, polyrhythm and groove, and propose how these studies can be seen as special cases of the predictive coding theory. We argue that musical rhythm exploits the brain’s general principles of prediction and propose that pleasure and desire for sensorimotor synchronization from musical rhythm may be a result of such mechanisms.

  12. Temporal correlation between auditory neurons and the hippocampal theta rhythm induced by novel stimulations in awake guinea pigs.

    Science.gov (United States)

    Liberman, Tamara; Velluti, Ricardo A; Pedemonte, Marisa

    2009-11-17

    The hippocampal theta rhythm is associated with the processing of sensory systems such as touch, smell, vision and hearing, as well as with motor activity, the modulation of autonomic processes such as cardiac rhythm, and learning and memory processes. The discovery of temporal correlation (phase locking) between the theta rhythm and both visual and auditory neuronal activity has led us to postulate the participation of such rhythm in the temporal processing of sensory information. In addition, changes in attention can modify both the theta rhythm and the auditory and visual sensory activity. The present report tested the hypothesis that the temporal correlation between auditory neuronal discharges in the inferior colliculus central nucleus (ICc) and the hippocampal theta rhythm could be enhanced by changes in sensory stimulation. We presented chronically implanted guinea pigs with auditory stimuli that varied over time, and recorded the auditory response during wakefulness. It was observed that the stimulation shifts were capable of producing the temporal phase correlations between the theta rhythm and the ICc unit firing, and they differed depending on the stimulus change performed. Such correlations disappeared approximately 6 s after the change presentation. Furthermore, the power of the hippocampal theta rhythm increased in half of the cases presented with a stimulation change. Based on these data, we propose that the degree of correlation between the unitary activity and the hippocampal theta rhythm varies with--and therefore may signal--stimulus novelty.

  13. Psychology of the Embrace: How Body Rhythms Communicate the Need to Indulge or Separate.

    Science.gov (United States)

    Koch, Sabine C; Rautner, Helena

    2017-11-29

    In the context of embodiment research, there has been a growing interest in phenomena of interpersonal resonance. Given that haptic communication is particularly under-researched, we focused on the phenomenon of embracing. When we embrace a dear friend to say good-bye at the end of a great evening, we typically first employ smooth and yielding movements with round transitions between muscular tensing and relaxing ( smooth , indulging rhythms ), and when the embrace is getting too long, we start to use slight patting ( sharp , fighting rhythms with sharp transitions) on the back or the shoulders of the partner in order to indicate that we now want to end the embrace. On the ground of interpersonal resonance, most persons (per-sonare, latin = to sound through) understand these implicit nonverbal signals, expressed in haptic tension-flow changes, and will react accordingly. To experimentally test the hypothesis that smooth, indulgent rhythms signal the wish to continue, and sharp, fighting rhythms signal the wish to separate from an embrace, we randomly assigned 64 participants, all students at the University of Heidelberg, to two differently sequenced embrace conditions: (a) with the fighting rhythm at the end of the sequence of two indulgent rhythms (Sequence A: smooth-smooth-sharp); and (b) with the fighting rhythm between two indulgent rhythms (Sequence B: smooth-sharp-smooth). Participants were embraced for 30 s by a female confe-derate with their eyes blindfolded to focus on haptic and kinesthetic cues without being distracted by visual cues. They were instructed to let go of a handkerchief that they held between the fingers of their dominant hand during the embrace, when they felt that the embracer signaled the wish to finish the embrace. Participants significantly more often dropped the handkerchief in the phase of the fighting rhythm, no matter in which location it occurred in the embrace sequence. We assume that we learn such rhythmic behaviors and their

  14. Psychology of the Embrace: How Body Rhythms Communicate the Need to Indulge or Separate

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    Sabine C. Koch

    2017-11-01

    Full Text Available In the context of embodiment research, there has been a growing interest in phenomena of interpersonal resonance. Given that haptic communication is particularly under-researched, we focused on the phenomenon of embracing. When we embrace a dear friend to say good-bye at the end of a great evening, we typically first employ smooth and yielding movements with round transitions between muscular tensing and relaxing (smooth, indulging rhythms, and when the embrace is getting too long, we start to use slight patting (sharp, fighting rhythms with sharp transitions on the back or the shoulders of the partner in order to indicate that we now want to end the embrace. On the ground of interpersonal resonance, most persons (per-sonare, latin = to sound through understand these implicit nonverbal signals, expressed in haptic tension-flow changes, and will react accordingly. To experimentally test the hypothesis that smooth, indulgent rhythms signal the wish to continue, and sharp, fighting rhythms signal the wish to separate from an embrace, we randomly assigned 64 participants, all students at the University of Heidelberg, to two differently sequenced embrace conditions: (a with the fighting rhythm at the end of the sequence of two indulgent rhythms (Sequence A: smooth-smooth-sharp; and (b with the fighting rhythm between two indulgent rhythms (Sequence B: smooth-sharp-smooth. Participants were embraced for 30 s by a female confe­derate with their eyes blindfolded to focus on haptic and kinesthetic cues without being distracted by visual cues. They were instructed to let go of a handkerchief that they held between the fingers of their dominant hand during the embrace, when they felt that the embracer signaled the wish to finish the embrace. Participants significantly more often dropped the handkerchief in the phase of the fighting rhythm, no matter in which location it occurred in the embrace sequence. We assume that we learn such rhythmic behaviors and

  15. Characteristics and classification of hippocampal θ rhythm induced by passive translational displacement.

    Science.gov (United States)

    Xie, Kangning; Yan, Yili; Fang, Xiaolei; Gao, Shangkai; Hong, Bo

    2012-04-25

    Theta rhythms in the hippocampus are believed to be the "metric" relating to various behavior patterns for free roaming rats. In this study, the theta rhythms were studied while rats either walked or were passively translated by a toy car on a linear track (referred to as WALK and TRANS respectively). For the similar running speeds in WALK and TRANS conditions, theta frequency and amplitude were both reduced during TRANS. Theta modulation of pyramidal cells during TRANS was reduced compared to that during WALK. Theta frequency was positively correlated with translation speed during TRANS. Theta rhythm remained apparent during TRANS and WALK after large dose of atropine sulfate (blocking the cholinergic pathway) was injected compared to still states. The present study demonstrated the patterns of theta rhythm induced by passive translation in rats and suggested that the Type I theta rhythm could occur during non-voluntary locomotion. We further argued that the perception of actual self-motion may be the underlying mechanism that initiates and modulates type I theta. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  16. Effects of exercise on circadian rhythms and mobility in aging Drosophila melanogaster.

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    Rakshit, Kuntol; Wambua, Rebecca; Giebultowicz, Tomasz M; Giebultowicz, Jadwiga M

    2013-11-01

    Daily life functions such as sleep and feeding oscillate with circa 24 h period due to endogenous circadian rhythms generated by circadian clocks. Genetic or environmental disruption of circadian rhythms is associated with various aging-related phenotypes. Circadian rhythms decay during normal aging, and there is a need to explore strategies that could avert age-related changes in the circadian system. Exercise was reported to delay aging in mammals. Here, we investigated whether daily exercise via stimulation of upward climbing movement could improve circadian rest/activity rhythms in aging Drosophila melanogaster. We found that repeated exercise regimen did not strengthen circadian locomotor activity rhythms in aging flies and had no effect on their lifespan. We also tested the effects of exercise on mobility and determined that regular exercise lowered age-specific climbing ability in both wild type and clock mutant flies. Interestingly, the climbing ability was most significantly reduced in flies carrying a null mutation in the core clock gene period, while rescue of this gene significantly improved climbing to wild type levels. Our work highlights the importance of period in sustaining endurance in aging flies exposed to physical challenge. © 2013.

  17. Effect of Spaceflight on the Circadian Rhythm, Lifespan and Gene Expression of Drosophila melanogaster

    Science.gov (United States)

    Xu, Kanyan

    2015-01-01

    Space travelers are reported to experience circadian rhythm disruption during spaceflight. However, how the space environment affects circadian rhythm is yet to be determined. The major focus of this study was to investigate the effect of spaceflight on the Drosophila circadian clock at both the behavioral and molecular level. We used China’s Shenzhou-9 spaceship to carry Drosophila. After 13 days of spaceflight, behavior tests showed that the flies maintained normal locomotor activity rhythm and sleep pattern. The expression level and rhythm of major clock genes were also unaffected. However, expression profiling showed differentially regulated output genes of the circadian clock system between space flown and control flies, suggesting that spaceflight affected the circadian output pathway. We also investigated other physiological effects of spaceflight such as lipid metabolism and lifespan, and searched genes significantly affected by spaceflight using microarray analysis. These results provide new information on the effects of spaceflight on circadian rhythm, lipid metabolism and lifespan. Furthermore, we showed that studying the effect of spaceflight on gene expression using samples collected at different Zeitgeber time could obtain different results, suggesting the importance of appropriate sampling procedures in studies on the effects of spaceflight. PMID:25798821

  18. Effect of spaceflight on the circadian rhythm, lifespan and gene expression of Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Lingling Ma

    Full Text Available Space travelers are reported to experience circadian rhythm disruption during spaceflight. However, how the space environment affects circadian rhythm is yet to be determined. The major focus of this study was to investigate the effect of spaceflight on the Drosophila circadian clock at both the behavioral and molecular level. We used China's Shenzhou-9 spaceship to carry Drosophila. After 13 days of spaceflight, behavior tests showed that the flies maintained normal locomotor activity rhythm and sleep pattern. The expression level and rhythm of major clock genes were also unaffected. However, expression profiling showed differentially regulated output genes of the circadian clock system between space flown and control flies, suggesting that spaceflight affected the circadian output pathway. We also investigated other physiological effects of spaceflight such as lipid metabolism and lifespan, and searched genes significantly affected by spaceflight using microarray analysis. These results provide new information on the effects of spaceflight on circadian rhythm, lipid metabolism and lifespan. Furthermore, we showed that studying the effect of spaceflight on gene expression using samples collected at different Zeitgeber time could obtain different results, suggesting the importance of appropriate sampling procedures in studies on the effects of spaceflight.

  19. A neural mass model of interconnected regions simulates rhythm propagation observed via TMS-EEG.

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    Cona, F; Zavaglia, M; Massimini, M; Rosanova, M; Ursino, M

    2011-08-01

    Knowledge of cortical rhythms represents an important aspect of modern neuroscience, to understand how the brain realizes its functions. Recent data suggest that different regions in the brain may exhibit distinct electroencephalogram (EEG) rhythms when perturbed by Transcranial Magnetic Stimulation (TMS) and that these rhythms can change due to the connectivity among regions. In this context, in silico simulations may help the validation of these hypotheses that would be difficult to be verified in vivo. Neural mass models can be very useful to simulate specific aspects of electrical brain activity and, above all, to analyze and identify the overall frequency content of EEG in a cortical region of interest (ROI). In this work we implemented a model of connectivity among cortical regions to fit the impulse responses in three ROIs recorded during a series of TMS/EEG experiments performed in five subjects and using three different impulse intensities. In particular we investigated Brodmann Area (BA) 19 (occipital lobe), BA 7 (parietal lobe) and BA 6 (frontal lobe). Results show that the model can reproduce the natural rhythms of the three regions quite well, acting on a few internal parameters. Moreover, the model can explain most rhythm changes induced by stimulation of another region, and inter-subject variability, by estimating just a few long-range connectivity parameters among ROIs. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. The maturation of cortical sleep rhythms and networks over early development.

    Science.gov (United States)

    Chu, C J; Leahy, J; Pathmanathan, J; Kramer, M A; Cash, S S

    2014-07-01

    Although neuronal activity drives all aspects of cortical development, how human brain rhythms spontaneously mature remains an active area of research. We sought to systematically evaluate the emergence of human brain rhythms and functional cortical networks over early development. We examined cortical rhythms and coupling patterns from birth through adolescence in a large cohort of healthy children (n=384) using scalp electroencephalogram (EEG) in the sleep state. We found that the emergence of brain rhythms follows a stereotyped sequence over early development. In general, higher frequencies increase in prominence with striking regional specificity throughout development. The coordination of these rhythmic activities across brain regions follows a general pattern of maturation in which broadly distributed networks of low-frequency oscillations increase in density while networks of high frequency oscillations become sparser and more highly clustered. Our results indicate that a predictable program directs the development of key rhythmic components and physiological brain networks over early development. This work expands our knowledge of normal cortical development. The stereotyped neurophysiological processes observed at the level of rhythms and networks may provide a scaffolding to support critical periods of cognitive growth. Furthermore, these conserved patterns could provide a sensitive biomarker for cortical health across development. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.