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1
Eldridge, Hannah Vandegrift. "Towards a Philosophy of Rhythm: Nietzsche’s Conflicting Rhythms." Journal of Literary Theory 12, no. 1 (March 26, 2018): 151–70. http://dx.doi.org/10.1515/jlt-2018-0009.
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Abstract In recent years, theories of rhythm have been proposed by a number of different disciplines, including historical poetics, generative metrics, cognitive literary studies, and evolutionary aesthetics. The wide range of fields indicates the transdisciplinary nature of rhythm as a phenomenon, as well as its complexity, highlighting the degree to which many of the central questions surrounding rhythm remain extraordinarily difficult even to state in terms that can traverse the disciplinary boundaries effortlessly transgressed by rhythm as a phenomenon. In particular, any theory of rhythm, whether in music, dance, sociology, or language, must grapple with two quandaries. First, the precise site of rhythm remains opaque: rhythms occur in, affect, and are produced by all of bodies, cultures, and universals (whether metaphysical or species-physiological). What is the relation between species-wide characteristic, individual body, cultural context, and the history of art making in the experience of rhythm? Second, rhythm is simultaneously a phenomenon of fixed, organizing form and one of dynamic, changing flow. How can rhythm encompass both the measurement of regular recurrences across time and the organizing of temporal phenomena as they unfold? In this article, I draw on Emile Benveniste and Henri Meschonnic to elucidate these quandaries or conflicts before turning to Friedrich Nietzsche’s work on rhythm. I argue that Nietzsche’s work with rhythm provides a historically situated model for how we might continue to take the questions and conflicts within rhythm seriously, rather than privileging an abstract and universally applicable theory of rhythm. This model is especially crucial for our own historical moment, when cultural-political emphasis on science and technology at the expense of aesthetics devalues all insights not presented in the form of countable data points or empirically testable facts. Nietzsche is, of course, one of the great critics of positivist-scientistic epistemologies, part of a long tradition questioning the naturalness of natural-scientific paradigms and alerting us to the metaphors at play even in the ›hard sciences‹. I use rhythm as one paradigmatic place to resist the importation of scientistic thought into discussions of language, literature, and culture. I show how Nietzsche’s writings on rhythm prove illuminating for contemporary understandings of rhythm because the tensions in his work are shaped by the quandaries inherent to rhythm that I have used Benveniste and Meschonnic to elaborate, namely the question of rhythm’s site as individual, cultural, or universal, and the conflict between rhythm as form and as flow. The question of the site of rhythm appears in Nietzsche’s discussions of Greek and Latin meters both in his philological works, in his aphorisms, and in his letters: on the one hand, he argues that Greek and Latin metrical and rhythmic resources are irrevocably lost to modern cultures (indicating that rhythm is a product of culture), while on the other, he emphasizes the impact of rhythm on the body and offers advice for replicating Ancient metrical and rhythmic techniques (suggesting that rhythm is based on physiological universals). And the conflict between flow and form appears as Nietzsche praises both the productive constraint created by large-scale, architectonic, or macro-formal rhythms and the freedom from such constraint enabled by small-scale, leitmotiv-based, or micro-formal rhythms. The conflicts in Nietzsche’s work between the loss and recovery of Ancient rhythms and between rhythm as small scale freedom vs. large scale constraint thus represent one particular unfolding of the dilemmas for rhythmical theory worked out by Benveniste and Meschonnic. The various modern disciplines engaged with rhythm will answer different sets of these questions in different ways. Most practitioners of, e. g., evolutionary aesthetics, neuroaesthetics, or cognitive poetics would no doubt contend that they are using the tools of the natural sciences to investigate long-standing humanistic inquiries. Nietzsche, as a critic of his own era’s scientific positivism who allows tensions inherent in these questions to remain open in his own work, is an ideal interlocutor with whom to ask whether even the adoption of these tools ends up placing excessive faith in natural-scientific paradigms and undercutting other—affective, bodily, metaphorical, poetic, etc.—ways of knowing, as I demonstrate briefly in the examples of evolutionary aesthetics and generative metrics. Because Nietzsche leaves open the conflicts over rhythm’s site and its qualities as form or flow, he can use individual bodily experience to make physiological arguments about the effects of rhythm on culture and vice versa: Nietzsche takes his bodily response to be an index of cultural values inherent to rhythmical practices. The particular values that Nietzsche critiques shift across his career—early on he condemns German musical and poetic rhythms for being too rigid, while later he sees them as pathologically heightening affect and emotion. In both cases, detrimental rhythmic practices lead to detrimental bodily practices and to the degeneration of culture, while rhythmic practices work as a bodily and cultural corrective. In his critiques of German forms and praises of Greek forms, and in the moments in which he brings them together, Nietzsche thus asserts the complex interrelation of culture, body, and history.
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Byron, Kyle. "Weapons for Witnessing." Religion and Society 11, no. 1 (September 1, 2020): 61–74. http://dx.doi.org/10.3167/arrs.2020.110105.
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Drawing on observations of the performances of street preachers in the United States—as well as the texts that inform them—this article explores the concept of rhythm within and beyond the anthropology of religion. More specifically, it develops an expansive concept of rhythm as multiple and interactive, focusing not on a singular rhythm, but on the rhythmic translations that shape the practice of street preaching. First, I argue that the material rhythms of urban infrastructure constrain the narrative rhythms of the street preacher’s sermon, producing a distinct homiletics. I then suggest that the ideological rhythms of war animate the narrative rhythms of the street preacher’s sermon, linking military strategies with tactics of evangelism. Examining the material, narrative, and ideological rhythms of streets, sermons, and military doctrine, this article advances an analytic framework whereby the intersecting rhythmic tensions that shape performance can be registered.
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Irlandini, Luigi Antonio. "Expanded Modal Rhythm." Revista Vórtex 5, no. 1 (June 30, 2017): 1–24. http://dx.doi.org/10.33871/23179937.2017.5.1.1859.
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This article is written by a composer on his own music. It describes a set of rhythmic organization principles used in my compositional research since 1989. These principles greately expand what is traditionally known as "modal rhythm" , which appears for the first time in the music of the 12th century polyphonists of the Notre Dame School: Leoninus and Perotinus. For this reason, I call this group of rhythmic principles "expanded modal rhythm" . They are a part of a larger context of temporal organization principles designed to generating ametric textures, complex polyrhythm and cross rhythms, and certain desired types or rhythmic flow. I use examples taken from four of my compositions.
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Barman, S. M., G. L. Gebber, and S. Zhong. "The 10-Hz rhythm in sympathetic nerve discharge." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 262, no. 6 (June 1, 1992): R1006—R1014. http://dx.doi.org/10.1152/ajpregu.1992.262.6.r1006.
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Frequency-domain analysis was used to characterize the relationships among the rhythmic discharges recorded simultaneously from two to four sympathetic nerves in unanesthetized decerebrate cats. The major new findings were as follows. 1) The 10-Hz rhythmic discharges of different nerves cohered strongly in baroreceptor-innervated and -denervated cats. 2) The interval between the discharges of two nerves was frequency dependent in the 10-Hz band in some cats, supporting the view that the 10-Hz rhythm is generated by multiple central circuits that are coupled. 3) In some cases the central circuits responsible for the 10-Hz rhythms nonuniformly affected different nerves. 4) In baroreceptor-innervated cats the coherence values for the cardiac-related discharges of any two nerves were significantly higher than those for the 10-Hz rhythms. 5) In baroreceptor-denervated cats the 10-Hz rhythmic discharges of different nerves cohered more strongly than the 2- to 6-Hz rhythms. 6) The 10-Hz rhythm usually was not a harmonic of the 2- to 6-Hz or cardiac-related rhythm. Thus these rhythms are generated independently.
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Fransen, Anne M. M., George Dimitriadis, Freek van Ede, and Eric Maris. "Distinct α- and β-band rhythms over rat somatosensory cortex with similar properties as in humans." Journal of Neurophysiology 115, no. 6 (June 1, 2016): 3030–44. http://dx.doi.org/10.1152/jn.00507.2015.
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We demonstrate distinct α- (7–14 Hz) and β-band (15–30 Hz) rhythms in rat somatosensory cortex in vivo using epidural electrocorticography recordings. Moreover, we show in rats that a genuine β-rhythm coexists alongside β-activity that reflects the second harmonic of the arch-shaped somatosensory α-rhythm. This demonstration of a genuine somatosensory β-rhythm depends on a novel quantification of neuronal oscillations that is based on their rhythmic nature: lagged coherence. Using lagged coherence, we provide two lines of evidence that this somatosensory β-rhythm is distinct from the second harmonic of the arch-shaped α-rhythm. The first is based on the rhythms' spatial properties: the α- and β-rhythms are demonstrated to have significantly different topographies. The second is based on the rhythms' temporal properties: the lagged phase-phase coupling between the α- and β-rhythms is demonstrated to be significantly less than would be expected if both reflected a single underlying nonsinusoidal rhythm. Finally, we demonstrate that 1) the lagged coherence spectrum is consistent between signals from rat and human somatosensory cortex; and 2) a tactile stimulus has the same effect on the somatosensory α- and β-rhythms in both rats and humans, namely suppressing them. Thus we not only provide evidence for the existence of genuine α- and β-rhythms in rat somatosensory cortex, but also for their homology to the primate sensorimotor α- and β-rhythms.
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Mathias, Brian, Anna Zamm, Pierre G. Gianferrara, Bernhard Ross, and Caroline Palmer. "Rhythm Complexity Modulates Behavioral and Neural Dynamics During Auditory–Motor Synchronization." Journal of Cognitive Neuroscience 32, no. 10 (October 2020): 1864–80. http://dx.doi.org/10.1162/jocn_a_01601.
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We addressed how rhythm complexity influences auditory–motor synchronization in musically trained individuals who perceived and produced complex rhythms while EEG was recorded. Participants first listened to two-part auditory sequences (Listen condition). Each part featured a single pitch presented at a fixed rate; the integer ratio formed between the two rates varied in rhythmic complexity from low (1:1) to moderate (1:2) to high (3:2). One of the two parts occurred at a constant rate across conditions. Then, participants heard the same rhythms as they synchronized their tapping at a fixed rate (Synchronize condition). Finally, they tapped at the same fixed rate (Motor condition). Auditory feedback from their taps was present in all conditions. Behavioral effects of rhythmic complexity were evidenced in all tasks; detection of missing beats (Listen) worsened in the most complex (3:2) rhythm condition, and tap durations (Synchronize) were most variable and least synchronous with stimulus onsets in the 3:2 condition. EEG power spectral density was lowest at the fixed rate during the 3:2 rhythm and greatest during the 1:1 rhythm (Listen and Synchronize). ERP amplitudes corresponding to an N1 time window were smallest for the 3:2 rhythm and greatest for the 1:1 rhythm (Listen). Finally, synchronization accuracy (Synchronize) decreased as amplitudes in the N1 time window became more positive during the high rhythmic complexity condition (3:2). Thus, measures of neural entrainment corresponded to synchronization accuracy, and rhythmic complexity modulated the behavioral and neural measures similarly.
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Solomon, Ty. "Rhythm and Mobilization in International Relations." International Studies Quarterly 63, no. 4 (August 29, 2019): 1001–13. http://dx.doi.org/10.1093/isq/sqz074.
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Abstract International Relations (IR) has rarely considered rhythm as a topic of analytical attention. Yet rhythms permeate many social and political phenomena, and their study contributes to core debates and empirical insights in contemporary IR. Rhythms are similar to but distinct from other forms of repetitive, iterative social action that have garnered increasing interest in IR, such as practices, habits, and routines. Each of these phenomena has rhythmic elements, but not all rhythmic phenomena are practical, habitual, or routine. Rhythm, then, is a distinct category of iterative action that is effectively positioned to unpack a wider array of practices in a broader range of cases. Moreover, contrary to common conceptions as simple repetition, the multiplicity and dynamism of social rhythms hold the potential to produce novel political formations. This article outlines a framework for the study of rhythms in IR by delineating some key features of social rhythms and three kinds of sociopolitical effects that they have in collective contexts. These theoretical developments are empirically applied to understand neglected aspects of mass mobilization during the Arab uprisings of 2011.
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Pintér, Csilla. "The significance of the varieties of parlando-rubato in the rhythmic language of Bluebeard’s Castle." Studia Musicologica 49, no. 3-4 (September 1, 2008): 369–82. http://dx.doi.org/10.1556/smus.49.2008.3-4.8.
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‘Parlando-rubato’ rhythm in Bartók’s thinking, does not mean complete rhythmic freedom; it is not necessarily accompanied by rubato tempi or rubato modes of interpretation. Musical declamation approximating to the rhythm of speech can be regulated by strict metrical structures, even if these do not follow a regular beat. Bartók’s writings dealing with the parlando phenomenon support the complexity and variability of ‘parlando-rubato’ as folk rhythms and performing practices. It was precisely the manifold nature of the parlando-rubato rhythm that enabled it to become the most important rhythmic foundation for musical declamation in Bluebeard’s Castle . The different level of rhythmic freedom of the characters not only reveal the contrast between their characteristic parlando types but also communicate their own personal rhythmic profile. The main aim of this study is to highlight those aspects of this musical phenomenon which greatly contributed to the 20th-century renewal and emancipation of rhythm while not eliminating rhythmic patterns based on bars.
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de Reus, Koen, Masayo Soma, Marianna Anichini, Marco Gamba, Marianne de Heer Kloots, Miriam Lense, Julia Hyland Bruno, Laurel Trainor, and Andrea Ravignani. "Rhythm in dyadic interactions." Philosophical Transactions of the Royal Society B: Biological Sciences 376, no. 1835 (August 23, 2021): 20200337. http://dx.doi.org/10.1098/rstb.2020.0337.
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This review paper discusses rhythmic interactions and distinguishes them from non-rhythmic interactions. We report on communicative behaviours in social and sexual contexts, as found in dyads of humans, non-human primates, non-primate mammals, birds, anurans and insects. We discuss observed instances of rhythm in dyadic interactions, identify knowledge gaps and propose suggestions for future research. We find that most studies on rhythmicity in interactive signals mainly focus on one modality (acoustic or visual) and we suggest more work should be performed on multimodal signals. Although the social functions of interactive rhythms have been fairly well described, developmental research on rhythms used to regulate social interactions is still lacking. Future work should also focus on identifying the exact timing mechanisms involved. Rhythmic signalling behaviours are widespread and critical in regulating social interactions across taxa, but many questions remain unexplored. A multidisciplinary, comparative cross-species approach may help provide answers. This article is part of the theme issue ‘Synchrony and rhythm interaction: from the brain to behavioural ecology’.
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Jones, Mari Riess, Lee Summerell, and Elizabeth Marshburn. "Recognizing Melodies: A Dynamic Interpretation." Quarterly Journal of Experimental Psychology Section A 39, no. 1 (February 1987): 89–121. http://dx.doi.org/10.1080/02724988743000051.
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Two experiments explore hypotheses about rhythm and contour in recognition of simple pitch strings (melodies). Target melodies that differed with respect to pitch relationships (interval and contour pitch differences) and rhythm, were presented to ordinary listeners who were told to learn the melodies (Phase I). In a subsequent recognition test (Phase II), listeners had to recognize these same target melodies although they were transposed to a different musical key. In recognition, target melodies appeared in the original rhythm or in new rhythms that simulated some pause properties of the original rhythm. Target melodies were interspersed with decoy melodies that either preserved the pitch contour of targets or did not; all appeared in the original rhythm and in new rhythms. Results indicated that a new rhythmic context lowered recognizability of target melodies, and that decoys were most confusing when they possessed the same “dynamic shape” (contour-plus-rhythm) as targets (Experiment 1). Also, target recognition improved with Phase I familiarity (Experiment 2), although rhythmic shifts remained detrimental across levels of target familiarity. Confusions based on “dynamic shape” accounted for a relatively high proportion of errors where familiarity with targets is low. Findings were interpreted in terms of a theory of context-sensitive dynamic attending in which remembering is assumed to involve recapitulation of the original rhythmical activities involved in attending to melodies.
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Zipse, Lauryn, Amanda Worek, Anthony J. Guarino, and Stefanie Shattuck-Hufnagel. "Tapped Out: Do People With Aphasia Have Rhythm Processing Deficits?" Journal of Speech, Language, and Hearing Research 57, no. 6 (December 2014): 2234–45. http://dx.doi.org/10.1044/2014_jslhr-l-13-0309.
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Purpose In this study, the authors tested whether people with aphasia (PWAs) show an impaired ability to process rhythm, both in terms of perception and production. Method Two experiments were conducted. In Experiment 1, 16 PWAs and 15 age-matched control participants performed 3 rhythm tasks: tapping along to short rhythms, tapping these same rhythms from memory immediately after presentation, and making same–different judgments about pairs of tapped rhythms that they heard. Comparison tasks measured same–different judgment ability with visual stimuli and nonverbal working memory (Corsi blocks). In Experiment 2, 14 PWAs and 16 control participants made same–different judgments for pairs of auditory stimuli that differed in terms of rhythm or pitch (for comparison). Results In Experiment 1, PWAs performed worse than control participants across most measures of rhythm processing. In contrast, PWAs and control participants did not differ in their performance on the comparison tasks. In Experiment 2, the PWAs performed worse than control participants across all conditions but with a more marked deficit in stimulus pairs that differed in rhythm than in those that differed in pitch. Conclusions The results support the hypothesis that at least some PWAs exhibit deficits of rhythm and timing. This may have implications for treatments involving tapping or other rhythmic cues.
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Wen, Olivia Xin, and Carol Lynne Krumhansl. "Perception of Pitch and Time in the Structurally Isomorphic Standard Rhythmic and Diatonic Scale Patterns." Music & Science 2 (January 1, 2019): 205920431987330. http://dx.doi.org/10.1177/2059204319873308.
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The three experiments reported here investigate how pitch and time interact in perception using the standard rhythmic pattern and the diatonic scale pattern, which share the intervallic structure of 2 2 1 2 2 2 1. They share a number of theoretical properties, including being cyclic with seven unique rotations. Experiment 1 measured rhythmic stability by dynamically accenting each of the events in each rhythm, called the probe accent; listeners rated how well the probe accent fit the rhythm. Listeners heard the rhythms in subgroups and with reference to a syncopation-shifted metrical hierarchy. Experiment 2 used the probe tone technique to measure the tonal stability of each tone in each mode beginning and ending on C. Higher ratings were given to tones earlier in the contexts and tones closer to C on both the chroma circle and the circle of fifths; influences were also found of tonal hierarchies of diatonic scales with corresponding accidentals. A measure of similarity derived from the probe ratings found the same order for the rhythms and modes which matched theoretical proposals of inter-rhythm and inter-mode distances. Experiment 3 presented all combinations of rhythms and modes; listeners judged how well the rhythm fit the mode. These judgments did not depend on the intervallic isomorphism between tone duration and interval size. Instead, the judgments depended on whether tonally stable events occurred where accents were judged as fitting well with the rhythm. Overall, the standard and diatonic patterns follow different perceptual hierarchies while sharing similar cognitive principles between rhythms, between modes, and across dimensions.
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Wang, Hui-Min, and Sheng-Chieh Huang. "Musical Rhythms Affect Heart Rate Variability: Algorithm and Models." Advances in Electrical Engineering 2014 (September 17, 2014): 1–14. http://dx.doi.org/10.1155/2014/851796.
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There were a lot of psychological music experiments and models but there were few psychological rhythm experiments and models. There were a lot of physiological music experiments but there were few physiological music models. There were few physiological rhythm experiments but there was no physiological rhythm model. We proposed a physiological rhythm model to fill this gap. Twenty-two participants, 4 drum loops as stimuli, and electrocardiogram (ECG) were employed in this work. We designed an algorithm to map tempo, complexity, and energy into two heart rate variability (HRV) measures, the standard deviation of normal-to-normal heartbeats (SDNN) and the ratio of low- and high-frequency powers (LF/HF); these two measures form the physiological valence/arousal plane. There were four major findings. Initially, simple and loud rhythms enhanced arousal. Secondly, the removal of fast and loud rhythms decreased arousal. Thirdly, fast rhythms increased valence. Finally, the removal of fast and quiet rhythms increased valence. Our work extended the psychological model to the physiological model and deepened the musical model into the rhythmic model. Moreover, this model could be the rules of automatic music generating systems.
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Grahn, Jessica A., and Matthew Brett. "Rhythm and Beat Perception in Motor Areas of the Brain." Journal of Cognitive Neuroscience 19, no. 5 (May 2007): 893–906. http://dx.doi.org/10.1162/jocn.2007.19.5.893.
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When we listen to rhythm, we often move spontaneously to the beat. This movement may result from processing of the beat by motor areas. Previous studies have shown that several motor areas respond when attending to rhythms. Here we investigate whether specific motor regions respond to beat in rhythm. We predicted that the basal ganglia and supplementary motor area (SMA) would respond in the presence of a regular beat. To establish what rhythm properties induce a beat, we asked subjects to reproduce different types of rhythmic sequences. Improved reproduction was observed for one rhythm type, which had integer ratio relationships between its intervals and regular perceptual accents. A subsequent functional magnetic resonance imaging study found that these rhythms also elicited higher activity in the basal ganglia and SMA. This finding was consistent across different levels of musical training, although musicians showed activation increases unrelated to rhythm type in the premotor cortex, cerebellum, and SMAs (pre-SMA and SMA). We conclude that, in addition to their role in movement production, the basal ganglia and SMAs may mediate beat perception.
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Kalyta, Alla. "Text rhythmic system: Its energetic and subliminal potentials." Linguistics Beyond and Within (LingBaW) 2 (December 30, 2016): 97–110. http://dx.doi.org/10.31743/lingbaw.5640.
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The article introduces scientific considerations concerning the energetic nature and origin of rhythm subliminal potential in a spoken text as well as the mechanisms of its impact on the recipient. The paper advances the idea that rhythm energetics and its subliminal potential is based on such postulates: (1) rhythm is generated in the speaker’s psyche at the levels of his/her unconscious (or existential being) and subconscious (or mental and transcendental beings) spheres; (2) the text rhythmic system has a definite emotional and pragmatic potentials that realize a latent manipulative and subliminal influence; (3) generation of the spoken text tempo-rhythm is carried out by means of integrating micro-rhythms of all levels of the speaker’s inner speech into the internal macro-rhythm, which is materialized in the form of an outer tempo-rhythm as a complex means of achieving a subliminal effect of speech. The article also outlines the prospects of studying a subliminal nature of rhythm.
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Zamoshchina, T. A., M. V. Meleshko, S. V. Logvinov, A. V. Matveуenko, L. N. Novitskaya, and Ye V. Ivanova. "The suprahiazmatic nucleus of the forward hypothalamus destruction and circadian rhythms of moving activity, body temperature and renal excretion of Nа+, Cа2+, K+, Li+ in rats in summer solstice." Bulletin of Siberian Medicine 10, no. 5 (October 28, 2011): 50–55. http://dx.doi.org/10.20538/1682-0363-2011-5-50-55.
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In summer solstice it was established that right or left suprachiazmatic nucleus lesion breaks circadian rhythms of rat's moving activity in «open field» and lithium urine excretion. Damage of the left nuclei in a greater degree affects formation circadian rhythm of sodium renal excretion, destruction of the right nuclei - the calcium rhythm organization. The rhythms of body temperature and potassium urine excretion find weak sensitivity to reenergizing right or left suprachiazmatic nucleus. At destruction right or left suprachiazmatic nucleus are formed rhythm's desynchronization, character and expressiveness are defined by an illumination mode.
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Gabbay, H., and A. Lev-Tov. "Alpha-1 Adrenoceptor Agonists Generate a “Fast” NMDA Receptor-Independent Motor Rhythm in the Neonatal Rat Spinal Cord." Journal of Neurophysiology 92, no. 2 (August 2004): 997–1010. http://dx.doi.org/10.1152/jn.00205.2004.
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Noradrenaline, a potent activator of rhythmogenic networks in adult mammals has not been reported to produce functional rhythmic patterns in isolated spinal cords of newborn rats. We now show that a “fast” (cycle time: 1–4 s) transient rhythm was induced in sacrococcygeal (SC) and rostral-lumbar spinal segments of the neonatal rat by bath-applied noradrenaline. The fast rhythm was blocked by 1 μM of the α1-adrenoceptor antagonist prazosin but not by 1–20 μM of the α2-adrenoceptor blocker yohimbine, it could be initiated and maintained by α1-adrenoceptor agonists, and it was accompanied by a slow nonlocomotor rhythm. Transection at the lumbosacral junction abolished the fast-thoracolumbar (TL) rhythm while the fast-SC and slow-TL rhythms were unaffected. The N-methyl-d-aspartate (NMDA) receptor antagonist 2-amino-5-phosphonopentanoic acid (AP5) abolished the slow- and did not interrupt the fast rhythm. Thus α1-adrenoceptor agonists induce an NMDA receptor-independent rhythm in the SC cord and modulate NMDA receptor-dependent rhythmicity in TL segments. Injection of current steps into S2 and flexor-dominated L2 motoneurons during the fast rhythm revealed a 20–30% decrease in input-resistance ( RN), coinciding with contralateral bursting. The RN of extensor-dominated L5 motoneurons did not vary with the fast rhythm. The rhythmic fluctuations of RN in L2 motoneurons were abolished, but the alternating left-right pattern of the fast rhythm was unchanged in midsagittally split TL cords. We suggest that the locomotor generators were not activated during the fast rhythm, that crossed-inhibitory pathways activated by SC projections controlled the rhythmic decrease in RN in L2 motoneurons, and that the alternating pattern of the split TL cord was maintained by excitatory SC projections.
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Kaplan, Thomas, Jonathan Cannon, Lorenzo Jamone, and Marcus Pearce. "Modeling enculturated bias in entrainment to rhythmic patterns." PLOS Computational Biology 18, no. 9 (September 29, 2022): e1010579. http://dx.doi.org/10.1371/journal.pcbi.1010579.
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Long-term and culture-specific experience of music shapes rhythm perception, leading to enculturated expectations that make certain rhythms easier to track and more conducive to synchronized movement. However, the influence of enculturated bias on the moment-to-moment dynamics of rhythm tracking is not well understood. Recent modeling work has formulated entrainment to rhythms as a formal inference problem, where phase is continuously estimated based on precise event times and their correspondence to timing expectations: PIPPET (Phase Inference from Point Process Event Timing). Here we propose that the problem of optimally tracking a rhythm also requires an ongoing process of inferring which pattern of event timing expectations is most suitable to predict a stimulus rhythm. We formalize this insight as an extension of PIPPET called pPIPPET (PIPPET with pattern inference). The variational solution to this problem introduces terms representing the likelihood that a stimulus is based on a particular member of a set of event timing patterns, which we initialize according to culturally-learned prior expectations of a listener. We evaluate pPIPPET in three experiments. First, we demonstrate that pPIPPET can qualitatively reproduce enculturated bias observed in human tapping data for simple two-interval rhythms. Second, we simulate categorization of a continuous three-interval rhythm space by Western-trained musicians through derivation of a comprehensive set of priors for pPIPPET from metrical patterns in a sample of Western rhythms. Third, we simulate iterated reproduction of three-interval rhythms, and show that models configured with notated rhythms from different cultures exhibit both universal and enculturated biases as observed experimentally in listeners from those cultures. These results suggest the influence of enculturated timing expectations on human perceptual and motor entrainment can be understood as approximating optimal inference about the rhythmic stimulus, with respect to prototypical patterns in an empirical sample of rhythms that represent the music-cultural environment of the listener.
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de l’Etoile, Shannon K., Christopher Bennett, and Cengiz Zopluoglu. "Infant Movement Response to Auditory Rhythm." Perceptual and Motor Skills 127, no. 4 (May 9, 2020): 651–70. http://dx.doi.org/10.1177/0031512520922642.
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Rhythmic entrainment occurs when an auditory rhythm drives an internal movement oscillator, thus providing a continuous time reference that improves temporal and spatial movement parameters. Entrainment processes and outcomes are well known for adults, but research is lacking for infants who might benefit from diagnosis and treatment of irregular rhythms within biological, sensorimotor, cognitive, and social domains. The present study used a combination of inertial measurement units and custom-made software to determine the amount, tempo, and regularity of movement in 28 infants aged 6-10 months while they were exposed to silence, an irregular rhythmic cue, or a regular rhythmic cue with tempo changes. We also assessed changes in the infants’ movement parameters following a one-week rhythm training protocol. While results revealed no significant effect of auditory condition on amount or tempo of movement, infant movement was significantly more regular when infants were exposed to 120 bpm (beats per minute) than to an irregular rhythmic cue or a 10% faster rhythmic cue (132 bpm). Infants showed no notable changes in movement amount, tempo, or regularity following one week of training involving auditory and physical rhythm. Overall, infants seem to engage in spontaneous movements with or without auditory rhythm but may not show tempo sensitivity through their movements. Increased movement regularity suggests that 120 bpm may be a preferred tempo for infants, at which they are more likely to demonstrate well-timed movements that may reflect interval entrainment. Infants’ auditory-motor systems appear not to respond to a 1-week rhythm training protocol.
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Aránguiz, Felipe Kong. "The Triple Synthesis of Rhythm." Deleuze and Guattari Studies 18, no. 1 (February 2024): 36–59. http://dx.doi.org/10.3366/dlgs.2024.0541.
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Stemming from a general study of rhythm in the work of Gilles Deleuze, we propose a distribution of this concept throughout three levels: a topic level, in which we place rhythm between chaos and measure; a dynamic level, in which we analyse the formation of rhythm towards its stabilisation as a spatio-temporal dynamism; and an unfolding, in which these dynamisms take on the form of rhythmic machines applied in music (refrain), in painting (sensation) and in cinema (montage and time crystals). In this last phase, the rhythmic devices of various arts lead to a genesis of time. We are thus driven to think and elaborate on the link between these two concepts, rhythm and time, in the writings of Deleuze. Bearing this purpose in mind, we turn to the schema of the three syntheses of time in Difference and Repetition. These syntheses show how time emerges from different ways of understanding repetition, in the place of which rhythm will then appear. We will compare this schema with the argument articulated by Deleuze in Logic of Sensation regarding rhythm in its pictorial form. This comparison will enable us to deduce that both concepts follow a parallel path arising from the same series of processes: vibration, coupling, resonance and forced movement. We will conclude that the schema proposed in Difference and Repetition and its aesthetic purpose delineate the ways in which rhythms unfold creatively. These three syntheses of rhythm are implicated in artistic processes.
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Sasahara, Kazutoshi, Ofer Tchernichovski, Miki Takahasi, Kenta Suzuki, and Kazuo Okanoya. "A rhythm landscape approach to the developmental dynamics of birdsong." Journal of The Royal Society Interface 12, no. 112 (November 2015): 20150802. http://dx.doi.org/10.1098/rsif.2015.0802.
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Unlike simple biological rhythms, the rhythm of the oscine bird song is a learned time series of diverse sounds that change dynamically during vocal ontogeny. How to quantify rhythm development is one of the most important challenges in behavioural biology. Here, we propose a simple method, called ‘rhythm landscape’, to visualize and quantify how rhythm structure, which is measured as durational patterns of sounds and silences, emerges and changes over development. Applying this method to the development of Bengalese finch songs, we show that the rhythm structure begins with a broadband rhythm that develops into diverse rhythms largely through branching from precursors. Furthermore, an information-theoretic measure, the Jensen–Shannon divergence, was used to characterize the crystallization process of birdsong rhythm, which started with a high rate of rhythm change and progressed to a stage of slow refinement. This simple method provides a useful description of rhythm development, thereby helping to reveal key temporal constraints on complex biological rhythms.
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Ordin, Mikhail, Leona Polyanskaya, David Maximiliano Gómez, and Arthur G. Samuel. "The Role of Native Language and the Fundamental Design of the Auditory System in Detecting Rhythm Changes." Journal of Speech, Language, and Hearing Research 62, no. 4 (April 15, 2019): 835–52. http://dx.doi.org/10.1044/2018_jslhr-s-18-0299.
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Purpose We investigated whether rhythm discrimination is mainly driven by the native language of the listener or by the fundamental design of the human auditory system and universal cognitive mechanisms shared by all people irrespective of rhythmic patterns in their native language. Method In multiple experiments, we asked participants to listen to 2 continuous acoustic sequences and to determine whether their rhythms were the same or different (AX discrimination). Participants were native speakers of 4 languages with different rhythmic properties (Spanish, French, English, and German) to understand whether the predominant rhythmic patterns of a native language affect sensitivity, bias, and reaction time in detecting rhythmic changes in linguistic (Experiment 2) and in nonlinguistic (Experiments 1 and 2) acoustic sequences. We examined sensitivity and bias measures, as well as reaction times. We also computed Bayes factors in order to assess the effect of native language. Results All listeners performed better (i.e., responded faster and manifested higher sensitivity and accuracy) when detecting the presence or absence of a rhythm change when the 1st stimulus in an AX test pair exhibited regular rhythm (i.e., a syllable-timed rhythmic pattern) than when the 1st stimulus exhibited irregular rhythm (i.e., stress-timed rhythmic pattern). This result pattern was observed both on linguistic and nonlinguistic stimuli and was not modulated by the native language of the participant. Conclusion We conclude that rhythm change detection is a fundamental function of a processing system that relies on general auditory mechanisms and is not modulated by linguistic experience.
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Wood, Debra E., Melissa Varrecchia, Michael Papernov, Denise Cook, and Devon C. Crawford. "Hormonal Modulation of Two Coordinated Rhythmic Motor Patterns." Journal of Neurophysiology 104, no. 2 (August 2010): 654–64. http://dx.doi.org/10.1152/jn.00846.2009.
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Neuromodulation is well known to provide plasticity in pattern generating circuits, but few details are available concerning modulation of motor pattern coordination. We are using the crustacean stomatogastric nervous system to examine how co-expressed rhythms are modulated to regulate frequency and maintain coordination. The system produces two related motor patterns, the gastric mill rhythm that regulates protraction and retraction of the teeth and the pyloric rhythm that filters food. These rhythms have different frequencies and are controlled by distinct mechanisms, but each circuit influences the rhythm frequency of the other via identified synaptic pathways. A projection neuron, MCN1, activates distinct versions of the rhythms, and we show that hormonal dopamine concentrations modulate the MCN1 elicited rhythm frequencies. Gastric mill circuit interactions with the pyloric circuit lead to changes in pyloric rhythm frequency that depend on gastric mill rhythm phase. Dopamine increases pyloric frequency during the gastric mill rhythm retraction phase. Higher gastric mill rhythm frequencies are associated with higher pyloric rhythm frequencies during retraction. However, dopamine slows the gastric mill rhythm frequency despite the increase in pyloric frequency. Dopamine reduces pyloric circuit influences on the gastric mill rhythm and upregulates activity in a gastric mill neuron, DG. Strengthened DG activity slows the gastric mill rhythm frequency and effectively reduces pyloric circuit influences, thus changing the frequency relationship between the rhythms. Overall dopamine shifts dependence of frequency regulation from intercircuit interactions to increased reliance on intracircuit mechanisms.
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Nolan, Francis, and Hae-Sung Jeon. "Speech rhythm: a metaphor?" Philosophical Transactions of the Royal Society B: Biological Sciences 369, no. 1658 (December 19, 2014): 20130396. http://dx.doi.org/10.1098/rstb.2013.0396.
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Is speech rhythmic? In the absence of evidence for a traditional view that languages strive to coordinate either syllables or stress-feet with regular time intervals, we consider the alternative that languages exhibit contrastive rhythm subsisting merely in the alternation of stronger and weaker elements. This is initially plausible, particularly for languages with a steep ‘prominence gradient’, i.e. a large disparity between stronger and weaker elements; but we point out that alternation is poorly achieved even by a ‘stress-timed’ language such as English, and, historically, languages have conspicuously failed to adopt simple phonological remedies that would ensure alternation. Languages seem more concerned to allow ‘syntagmatic contrast’ between successive units and to use durational effects to support linguistic functions than to facilitate rhythm. Furthermore, some languages (e.g. Tamil, Korean) lack the lexical prominence which would most straightforwardly underpin prominence of alternation. We conclude that speech is not incontestibly rhythmic, and may even be antirhythmic. However, its linguistic structure and patterning allow the metaphorical extension of rhythm in varying degrees and in different ways depending on the language, and it is this analogical process which allows speech to be matched to external rhythms.
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Burchardt, Lara S., Philipp Norton, Oliver Behr, Constance Scharff, and Mirjam Knörnschild. "General isochronous rhythm in echolocation calls and social vocalizations of the bat Saccopteryx bilineata." Royal Society Open Science 6, no. 1 (January 2019): 181076. http://dx.doi.org/10.1098/rsos.181076.
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Rhythm is an essential component of human speech and music but very little is known about its evolutionary origin and its distribution in animal vocalizations. We found a regular rhythm in three multisyllabic vocalization types (echolocation call sequences, male territorial songs and pup isolation calls) of the neotropical bat Saccopteryx bilineata . The intervals between element onsets were used to fit the rhythm for each individual. For echolocation call sequences, we expected rhythm frequencies around 6–24 Hz, corresponding to the wingbeat in S. bilineata which is strongly coupled to echolocation calls during flight. Surprisingly, we found rhythm frequencies between 6 and 24 Hz not only for echolocation sequences but also for social vocalizations, e.g. male territorial songs and pup isolation calls, which were emitted while bats were stationary. Fourier analysis of element onsets confirmed an isochronous rhythm across individuals and vocalization types. We speculate that attentional tuning to the rhythms of echolocation calls on the receivers' side might make the production of equally steady rhythmic social vocalizations beneficial.
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Heynckes, Miriam, Kim Hoffmann, Elia Formisano, Federico De Martino, and Peter De Weerd. "Predictability awareness rather than mere predictability enhances the perceptual benefits for targets in auditory rhythms over targets following temporal cues." PLOS ONE 18, no. 10 (October 27, 2023): e0284755. http://dx.doi.org/10.1371/journal.pone.0284755.
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Sounds following a cue or embedded in a periodic rhythm are processed more effectively than sounds that are part of an aperiodic rhythm. One might also expect that a sound embedded in a periodic rhythm is processed more effectively than a sound following a single temporal cue. Such a finding would follow the theory that the entrainment of neural rhythmic activity by periodic stimuli renders the prediction of upcoming stimuli more efficient. We conducted a psychophysical experiment in which we tested the behavioral elements of this idea. Targets in periodic and aperiodic rhythms, if they occurred, always appeared at the same moment in time, and thus were fully predictable. In a first condition, participants remained unaware of this. In a second condition, an explicit instruction on the temporal location of the targets embedded in rhythms was provided. We assessed sensitivity and reaction times to the target stimuli in a difficult temporal detection task, and contrasted performance in this task to that obtained for targets temporally cued by a single preceding cue. Irrespective of explicit information about target predictability, target detection performance was always better in the periodic and temporal cue conditions, compared to the aperiodic condition. However, we found that the mere predictability of an acoustic target within a periodic rhythm did not allow participants to detect the target any better than in a condition where the target’s timing was predicted by a single temporal cue. Only when participants were made aware of the specific moment in the periodic rhythm where the target could occur, did sensitivity increase. This finding suggests that a periodic rhythm is not automatically sufficient to provide perceptual benefits compared to a condition predictable yet not rhythmic condition (a cue). In some conditions, as shown here, these benefits may only occur in interaction with other factors such as explicit instruction and directed attention.
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DOYLE, SUSAN E., MICHAEL S. GRACE, WILSON McIVOR, and MICHAEL MENAKER. "Circadian rhythms of dopamine in mouse retina: The role of melatonin." Visual Neuroscience 19, no. 5 (September 2002): 593–601. http://dx.doi.org/10.1017/s0952523802195058.
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Both dopamine and melatonin are important for the regulation of retinal rhythmicity, and substantial evidence suggests that these two substances are mutually inhibitory factors that act as chemical analogs of day and night. A circadian oscillator in the mammalian retina regulates melatonin synthesis. Here we show a circadian rhythm of retinal dopamine content in the mouse retina, and examine the role of melatonin in its control. Using high-performance liquid chromatography (HPLC), we measured levels of dopamine and its two major metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), in retinas of C3H+/+ mice (which make melatonin) and C57BL/6J mice that are genetically incapable of melatonin synthesis. In a light/dark cycle both strains of mice exhibited daily rhythms of retinal dopamine, DOPAC, and HVA content. However, after 10 days in constant darkness (DD), a circadian rhythm in dopamine levels was present in C3H, but not in C57 mice. C57 mice given ten daily injections of melatonin in DD exhibited a robust circadian rhythm of retinal dopamine content whereas no such rhythm was present in saline-injected controls. Our results demonstrate that (1) a circadian clock generates rhythms of dopamine content in the C3H mouse retina, (2) mice lacking melatonin also lack circadian rhythms of dopamine content, and (3) dopamine rhythms can be generated in these mice by cyclic administration of exogenous melatonin. Our results also indicate that circadian rhythms of retinal dopamine depend upon the rhythmic presence of melatonin, but that cyclic light can drive dopamine rhythms in the absence of melatonin.
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Lakin-Thomas, Patricia L., Gooch Van D., and Mark Ramsdale. "Rhythms of differentiation and diacylglycerol in Neurospora." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 356, no. 1415 (November 29, 2001): 1711–15. http://dx.doi.org/10.1098/rstb.2001.0966.
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Although the fungus Neurospora crassa is a relatively simple lower eukaryote, its circadian system may be more complex than previously thought. In this paper we review evidence suggesting that there may be several output pathways coupled in complex ways to a single oscillator, or that there may be more than one oscillator driving independent output pathways. We have described two new rhythms in Neurospora that are not tightly coupled to the rhythm of conidiation bands that is the standard assay for the state of the Neurospora circadian clock. The first is a rhythm in the timing of differentiation, i.e. the production of aerial hyphae and spores. Large regions of the mycelium differentiate synchronously, as if responding to a spatially widespread signal. This rhythm may be distinct from the timer that sets the determination switch controlling the spatial pattern of conidiation bands. The second new rhythm is an oscillation in the levels of the neutral lipid diacylglycerol (DAG). This rhythm is found in all regions of a colony and is not always in phase with the rhythm of conidiation bands. The DAG rhythm shares some characteristics with the differentiation rhythm and has the potential to act as the signal that induces rhythmic differentiation.
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Padulo, Johnny, Alin Larion, Olfa Turki, Ionel Melenco, Cristian Popa, Stefano Palermi, Gian Mario Migliaccio, Stefania Mannarini, and Alessandro Alberto Rossi. "Ecological and Construct Validity of a New Technical Level Cuban Dance Field Test." International Journal of Environmental Research and Public Health 18, no. 24 (December 16, 2021): 13287. http://dx.doi.org/10.3390/ijerph182413287.
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The study aimed to explore the sensitivity and specificity of a new methodological approach related to the musical rhythm for discriminating a competitive Cuban dancer’s (CDCs) level. Thirty CDCs (Age 23.87 ± 1.76 years, body mass 60.33 ± 9.45 kg, stature 1.68 ± 0.07 m) were divided into three groups: beginner (BEG, n = 10), intermediate (INT, n = 10), and advanced (ADV, n = 10) according to their training experience/level. Each dancer was assessed while dancing at three different musical rhythms: fast (118 BPM), medium (96 BPM), and slow (82 BPM). The assessed variables were average heart rate (HRM), peak (HRP), and dancing time (DCT). The ADV group succeeded at all three musical combinations (317, 302, 309 s for 82, 96, 118 BPM). The INT group correctly performed only the first two combinations (304, 304 s for 82, 96 BPM), while a significant time difference was shown at the fast musical rhythm (198 ± 6.64 s) compared to the medium (p < 0.001) and slow rhythms (p < 0.001) respectively. As the speed of the musical rhythms increased, the BEG group was not able to follow the rhythm: their results were 300 ± 1.25 s for the slow musical rhythm, 94.90 ± 12.80 s for the medium musical rhythm and 34.10 ± 5.17 s for the fast musical rhythm (p < 0.001). The HRM and HRP grew along with the increase in musical rhythm for all groups (p < 0.001). The ROC analysis showed a high sensitivity and specificity in discriminating the groups for each rhythm’s condition. The BEG and INT groups showed an AUC = 0.864 (95% CI = 0.864–0.954); INT and ADV showed an AUC = 0.864 (95% CI = 0.864–0.952); BEG and ADV showed an AUC = 0.998 (95% CI = 0.993–1.000). The results of this study provided evidence to support the construct and ecological validity of the time of the musical rhythms related to competitive CDCs. Furthermore, the differences in the performances according to various musical rhythms, fast (118 BPM), medium (96 BPM), and slow (82 BPM), succeeded in discriminating a dancer’s level. Coaches and strength and conditioning professionals should include the Cuban Dance Field Test (CDFT) in their test battery when dealing with talent detection, selection, and development.
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Farr, Lynne, Catherine Todero, and Lonna Boen. "Reducing Disruption of Circadian Temperature Rhythm Following Surgery." Biological Research For Nursing 2, no. 4 (April 2001): 257–66. http://dx.doi.org/10.1177/109980040100200405.
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Temperature and other circadian rhythms are disrupted following surgery and other traumatic events. During recovery, coordination between temperature rhythms and other rhythmic physiologic processes is reduced. Studies of animals and humans have shown that return of synchrony is not immediate, but that it is important in the recovery process. The purpose of this study was to test a combination of cues that have been shown to adjust the timing of circadian temperature rhythm. The combined cues consisted of timed ingestion of caffeine and protein foods and adjustment of the sleep/wake cycle. The intervention was tested in 26 age-and gender-matched maxillofacial surgery patients. Patients were randomly assigned to control or experimental groups. Circadian temperature rhythm was measured by continuous monitoring with axillary probes and miniature recorders before and after surgery. Following surgery, both experimental and control subjects displayed 24-hour circadian temperature rhythms; however, the peak-to-trough difference was decreased more following surgery in the control subjects than in the subjects who had prepared for surgery by practicing the intervention. Control subjects also had less day-to-day stability in the phase of their rhythms following surgery. These results suggest that the intervention reduced circadian disruption following surgery and provides a way for patients to prepare themselves to resist rhythm changes.
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Zhong, S., S. Y. Zhou, G. L. Gebber, and S. M. Barman. "Coupled oscillators account for the slow rhythms in sympathetic nerve discharge and phrenic nerve activity." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 272, no. 4 (April 1, 1997): R1314—R1324. http://dx.doi.org/10.1152/ajpregu.1997.272.4.r1314.
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Phase-locked slow rhythms in sympathetic nerve discharge (SND) and phrenic nerve activity (PNA) are generally thought to arise from a common brain stem "cardiorespiratory" oscillator. The results obtained in vagotomized and baroreceptor-denervated cats anesthetized with pentobarbital sodium do not support this view. First, partial coherence analysis revealed that the discharges of pairs of sympathetic nerves remained correlated at the frequency of the central respiratory cycle after mathematical removal of the portion of these signals common to PNA. The residual coherence suggests that the slow rhythm in SND is dependent on central mechanisms in addition to those responsible for rhythmic PNA. Second, the rhythms in SND and PNA became coupled in a 2:1 relationship during either moderate systemic hypocapnia or hypercapnia. Third, the slow rhythm in SND was maintained when rhythmic PNA was eliminated during extreme hypocapnia. Fourth, during extreme hypercapnia, coherence of the rhythms in SND and PNA was drastically reduced. These results suggest that the slow rhythms in SND and PNA arise from separate oscillators that are normally coupled.
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Rouse, Andrew A., Aniruddh D. Patel, and Mimi H. Kao. "Vocal learning and flexible rhythm pattern perception are linked: Evidence from songbirds." Proceedings of the National Academy of Sciences 118, no. 29 (July 16, 2021): e2026130118. http://dx.doi.org/10.1073/pnas.2026130118.
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Rhythm perception is fundamental to speech and music. Humans readily recognize a rhythmic pattern, such as that of a familiar song, independently of the tempo at which it occurs. This shows that our perception of auditory rhythms is flexible, relying on global relational patterns more than on the absolute durations of specific time intervals. Given that auditory rhythm perception in humans engages a complex auditory–motor cortical network even in the absence of movement and that the evolution of vocal learning is accompanied by strengthening of forebrain auditory–motor pathways, we hypothesize that vocal learning species share our perceptual facility for relational rhythm processing. We test this by asking whether the best-studied animal model for vocal learning, the zebra finch, can recognize a fundamental rhythmic pattern—equal timing between event onsets (isochrony)—based on temporal relations between intervals rather than on absolute durations. Prior work suggests that vocal nonlearners (pigeons and rats) are quite limited in this regard and are biased to attend to absolute durations when listening to rhythmic sequences. In contrast, using naturalistic sounds at multiple stimulus rates, we show that male zebra finches robustly recognize isochrony independent of absolute time intervals, even at rates distant from those used in training. Our findings highlight the importance of comparative studies of rhythmic processing and suggest that vocal learning species are promising animal models for key aspects of human rhythm perception. Such models are needed to understand the neural mechanisms behind the positive effect of rhythm on certain speech and movement disorders.
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Smith, J. C., A. P. L. Abdala, H. Koizumi, I. A. Rybak, and J. F. R. Paton. "Spatial and Functional Architecture of the Mammalian Brain Stem Respiratory Network: A Hierarchy of Three Oscillatory Mechanisms." Journal of Neurophysiology 98, no. 6 (December 2007): 3370–87. http://dx.doi.org/10.1152/jn.00985.2007.
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Mammalian central pattern generators (CPGs) producing rhythmic movements exhibit extremely robust and flexible behavior. Network architectures that enable these features are not well understood. Here we studied organization of the brain stem respiratory CPG. By sequential rostral to caudal transections through the pontine-medullary respiratory network within an in situ perfused rat brain stem–spinal cord preparation, we showed that network dynamics reorganized and new rhythmogenic mechanisms emerged. The normal three-phase respiratory rhythm transformed to a two-phase and then to a one-phase rhythm as the network was reduced. Expression of the three-phase rhythm required the presence of the pons, generation of the two-phase rhythm depended on the integrity of Bötzinger and pre-Bötzinger complexes and interactions between them, and the one-phase rhythm was generated within the pre-Bötzinger complex. Transformation from the three-phase to a two-phase pattern also occurred in intact preparations when chloride-mediated synaptic inhibition was reduced. In contrast to the three-phase and two-phase rhythms, the one-phase rhythm was abolished by blockade of persistent sodium current ( INaP). A model of the respiratory network was developed to reproduce and explain these observations. The model incorporated interacting populations of respiratory neurons within spatially organized brain stem compartments. Our simulations reproduced the respiratory patterns recorded from intact and sequentially reduced preparations. Our results suggest that the three-phase and two-phase rhythms involve inhibitory network interactions, whereas the one-phase rhythm depends on INaP. We conclude that the respiratory network has rhythmogenic capabilities at multiple levels of network organization, allowing expression of motor patterns specific for various physiological and pathophysiological respiratory behaviors.
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Bhuvaneswari, E., and S. Sivaprasad. "Impact of photoperiod on circadian trehalose and trehalase rhythms in the digestive system of silkworm, Bombyx mori." Journal of Applied and Natural Science 5, no. 1 (June 1, 2013): 82–94. http://dx.doi.org/10.31018/jans.v5i1.287.
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Circadian trehalose and trehalase rhythms were studied in the digestive system of Bombyx mori under 12 hr light-dark cycle (LD), continuous light (LL) and continuous dark (DD). The rhythmic changes were interpreted as synthetic cycles in gut wall and release cycles in gut lumen. The trehalose rhythm of gut wall comprised 8 trehalose synthetic cycles (TS cycles) under LD and LL and 7 under DD. The 24 hr trehalose rhythm of LD and LL was clock shifted to 27.2 hr under DD. The trehalose rhythm included 4 TR cycles under LD, 5 under LL and DD in the gut lumen and the 24 hr rhythm of LD was clock shifted to 19.2 hr under LL and DD. In the gut wall trehalase rhythm maintained 8 trehalase enzyme synthetic cycles (TES cycles) under LD, 10 LL and 7 under DD and the 24 hr rhythm of LD was clock shifted to 19.2 hr under LL and 27.2 hr under DD. In the gut lumen it included 4 TER cycles under LD and DD, 5 under LL and its 24-hr rhythm was advanced to 19.2 hr. Further analysis of data showed that LD favours trehalose synthesis, while LL and DD favour trehalase synthesis.
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Kim, Chyon Hae, Kenta Yonekura, and Shigeki Sugano. "Force Masking Humanoid Robot System." Journal of Robotics and Mechatronics 26, no. 2 (April 20, 2014): 264. http://dx.doi.org/10.20965/jrm.2014.p0264.
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This force masking humanoid robot system had been developed for a psychological experiment that confirms the rhythmic modalities required by humans when they play rope turning with a robot. Although a person feels many types of rhythms in physical rhythmic cooperation with a robot, what rhythms are required for the cooperation had not been investigated yet. This system is an effective tool to investigate the effectiveness of the force rhythm in physical cooperations.
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Cameron, Daniel, Keith Potter, Geraint Wiggins, and Marcus Pearce. "Perception of Rhythmic Similarity is Asymmetrical, and Is Influenced by Musical Training, Expressive Performance, and Musical Context." Timing & Time Perception 5, no. 3-4 (December 8, 2017): 211–27. http://dx.doi.org/10.1163/22134468-00002085.
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Rhythm is an essential part of the structure, behaviour, and aesthetics of music. However, the cognitive processing that underlies the perception of musical rhythm is not fully understood. In this study, we tested whether rhythm perception is influenced by three factors: musical training, the presence of expressive performance cues in human-performed music, and the broader musical context. We compared musicians and nonmusicians’ similarity ratings for pairs of rhythms taken from Steve Reich’s Clapping Music. The rhythms were heard both in isolation and in musical context and both with and without expressive performance cues. The results revealed that rhythm perception is influenced by the experimental conditions: rhythms heard in musical context were rated as less similar than those heard in isolation; musicians’ ratings were unaffected by expressive performance, but nonmusicians rated expressively performed rhythms as less similar than those with exact timing; and expressively-performed rhythms were rated as less similar compared to rhythms with exact timing when heard in isolation but not when heard in musical context. The results also showed asymmetrical perception: the order in which two rhythms were heard influenced their perceived similarity. Analyses suggest that this asymmetry was driven by the internal coherence of rhythms, as measured by normalized Pairwise Variability Index (nPVI). As predicted, rhythms were perceived as less similar when the first rhythm in a pair had greater coherence (lower nPVI) than the second rhythm, compared to when the rhythms were heard in the opposite order.
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Nakazawa, Ken, Antonio R. Granata, and Morton I. Cohen. "Synchronized Fast Rhythms in Inspiratory and Expiratory Nerve Discharges During Fictive Vocalization." Journal of Neurophysiology 83, no. 3 (March 1, 2000): 1415–25. http://dx.doi.org/10.1152/jn.2000.83.3.1415.
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In precollicular decerebrate and paralyzed cats, respiratory nerve activities were recorded during fictive vocalization (FV), which consisted of a distinctive pattern of 1) decreased inspiratory (I) and expiratory (E) phase durations, 2) marked increase of phrenic activity and moderate changes of recurrent laryngeal (RL) and superior laryngeal (SL) I activities, and 3) massive recruitment of laryngeal and abdominal (ABD; lumbar) E activities. FV was produced by electrical stimulation (100 Hz) in the midbrain periaqueductal gray (PAG) or its putative descending pathways in the ventrolateral pons (VLP). Spectral and correlation analyses revealed three types of effect on fast rhythms during FV. 1) I activities: the coherent high-frequency oscillations in I (I-HFO, 60–90 Hz) present in phrenic and RL discharges during the control state did not change qualitatively, but there was an increase of power and a moderate increase (4–10 Hz) of frequency. Sometimes a distinct relatively weak stimulus-locked rhythm appeared. 2) RL and SL activities during E: in recruited discharges, a prominent intrinsic rhythm (coherent E-HFOs at 50–70 Hz) appeared; sometimes a distinct relatively strong stimulus-locked rhythm appeared. 3) ABD activities during E: this recruited activity had no intrinsic rhythm but had an evoked oscillation locked to the stimulus frequency. Thus FV is characterized by 1) appearance of prominent coherent intrinsic rhythms in RL and SL E discharges, which presumably arise as a result of excitation and increased interactions in laryngeal networks; 2) modification of intrinsic rhythmic interactions in inspiratory networks; and 3) evoked rhythms in augmenting-E neuron networks without occurrence of intrinsic rhythms.
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Taylor, Sharmila, and Anuja. "DELHI GHARANA MODERN USAGE AND TRENDS OF THE WESTERN EAGLE OF TABLA INSTRUMENT IN RHYTHM INSTRUMENTS." International Journal of Research -GRANTHAALAYAH 3, no. 1SE (January 31, 2015): 1–4. http://dx.doi.org/10.29121/granthaalayah.v3.i1se.2015.3482.
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Rhythm is a very important contribution to music. If seen, the entire music world is absorbed in the rhythm itself. If music does not have a rhythm, then music cannot be imagined. The three genres of music that make up music together. The work of singing, playing, dancing and playing them in the same manner is the rhythm. "Tal is an integral part of music and is also a powerful medium of joy. Taal takes Rasanand to the climax by being used in music as various rhythms. Just as the description of various ragas is found in singing. Similarly, the rhythms of different rhythmic rhythms are also found in the rhythm, the performance of different types of lions such as dugun, tigun, aad, kuad, etc. is shown through the tal.
संगीत में ताल का बहुत ही महत्वपूर्ण योगदान है। अगर देखा जाए तो ताल में ही पूरा संगीत जगत समाया हुआ है। अगर संगीत में ताल न हो तो संगीत की कल्पना भी नहीं की जा सकती है। संगीत की वह तीनों विधाएं जिससे मिलकर संगीत बना है। गायन, वादन, नृत्य इनको समान रूप में चलाने का कार्य ताल ही करती है। ‘‘ताल संगीत का अभिन्न अंग होने के साथ ही आनन्दोत्पत्ति का सबल माध्यम भी है। ताल विभिन्न लयकारी के रूप से संगीत में प्रयुक्त होकर रसानन्द को चरमोत्कर्ष पर पहंुचाता है। जिस प्रकार गायन में विभिन्न रागों का वर्णन मिलता है। इसी प्रकार ताल में भी विभिन्न लयकारी वाले तालों का वर्णन मिलता है, कहीं समान कहीं असमान कहीं दुगुन, तिगुन, आड, कुआड आदि भिन्न-भिन्न प्रकार की लयों का प्रदर्शन ताल के माध्यम से दर्शाया जाता है।
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Tichko, Parker, Nicole Page, Ji Chul Kim, Edward W. Large, and Psyche Loui. "Neural Entrainment to Musical Pulse in Naturalistic Music Is Preserved in Aging: Implications for Music-Based Interventions." Brain Sciences 12, no. 12 (December 7, 2022): 1676. http://dx.doi.org/10.3390/brainsci12121676.
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Neural entrainment to musical rhythm is thought to underlie the perception and production of music. In aging populations, the strength of neural entrainment to rhythm has been found to be attenuated, particularly during attentive listening to auditory streams. However, previous studies on neural entrainment to rhythm and aging have often employed artificial auditory rhythms or limited pieces of recorded, naturalistic music, failing to account for the diversity of rhythmic structures found in natural music. As part of larger project assessing a novel music-based intervention for healthy aging, we investigated neural entrainment to musical rhythms in the electroencephalogram (EEG) while participants listened to self-selected musical recordings across a sample of younger and older adults. We specifically measured neural entrainment to the level of musical pulse—quantified here as the phase-locking value (PLV)—after normalizing the PLVs to each musical recording’s detected pulse frequency. As predicted, we observed strong neural phase-locking to musical pulse, and to the sub-harmonic and harmonic levels of musical meter. Overall, PLVs were not significantly different between older and younger adults. This preserved neural entrainment to musical pulse and rhythm could support the design of music-based interventions that aim to modulate endogenous brain activity via self-selected music for healthy cognitive aging.
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Kiranmai, M. Sai, and M. Raajitha. "A COMPREHENSIVE REVIEW ON CHRONOTHERAPEUTICS." International Journal of Pharmaceutical Sciences and Medicine 8, no. 3 (March 30, 2023): 82–108. http://dx.doi.org/10.47760/ijpsm.2023.v08i03.007.
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Chronotherapy refers to the use of circadian, ultradian, infradian & seasonal, or other rhythmic cycles in the application of therapy. There are a number of conditions that show a circadian pattern and advantages could be taken by timing and adjusting the administration of drugs according to the circadian rhythm of the disease. Chronotherapy can be divided into three categories: time-controlled systems, in which the drug release is primarily controlled by the delivery system; stimuli-induced PDDS, in which release is controlled by the stimuli, such as the pH or intestinal enzymes; or externally regulated systems, in which release is programmed by external stimuli such as magnetism, ultrasound, electrical effect, and irradiation. The symptoms of some diseases, such as asthma, arthritis, depression, ulcer, allergic rhinitis, sleep disturbances, etc., are influenced by circadian rhythms. The biological clock of the human body is based on solar and lunar adaptations. The circadian rhythm is the primary rhythm that the biological clock adheres to. The functioning of the brain, behavior, and cognition can all be significantly impacted by circadian rhythm disruption. The use of chronotherapeutics can help with this. The recent interest that has occurred in the field of chronotherapeutics is to match the circadian rhythms of the disease for the successful treatment of the disease.
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Bebas, Piotr, Bronislaw Cymborowski, and Jadwiga M. Giebultowicz. "Circadian rhythm of acidification in insect vas deferens regulated by rhythmic expression of vacuolar H+-ATPase." Journal of Experimental Biology 205, no. 1 (January 1, 2002): 37–44. http://dx.doi.org/10.1242/jeb.205.1.37.
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SUMMARY Recent studies have demonstrated that the peripheral tissues of vertebrates and invertebrates contain circadian clocks; however, little is known about their functions and the rhythmic outputs that they generate. To understand clock-controlled rhythms at the cellular level, we investigated a circadian clock located in the reproductive system of a male moth (the cotton leaf worm Spodoptera littoralis) that is essential for the production of fertile spermatozoa. Previous work has demonstrated that spermatozoa are released from the testes in a daily rhythm and are periodically stored in the upper vas deferens (UVD). In this paper, we demonstrate a circadian rhythm in pH in the lumen of the UVD, with acidification occurring during accumulation of spermatozoa in the lumen. The daily rhythm in pH correlates with a rhythmic increase in the expression of a proton pump, the vacuolar H+-ATPase (V-ATPase), in the apical portion of the UVD epithelium. Rhythms in pH and V-ATPase persist in light/dark cycles and constant darkness, but are abolished in constant light, a condition that disrupts clock function and renders spermatozoa infertile. Treatment with colchicine impairs the migration of V-ATPase-positive vesicles to the apical cell membrane and abates the acidification of the UVD lumen. Bafilomycin, a selective inhibitor of V-ATPase activity, also prevents the decline in luminal pH. We conclude that the circadian clock generates a rhythm of luminal acidification by regulating the levels and subcellular distribution of V-ATPase in the UVD epithelium. Our data provide the first evidence for circadian control of V-ATPase, the fundamental enzyme that provides the driving force for numerous secondary transport processes. They also demonstrate how circadian rhythms displayed by individual cells contribute to the synchrony of physiological processes at the organ level.
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Wang, Manli, Hang Yu, Song Li, Yang Xiang, and Weidong Le. "Altered Biological Rhythm and Alzheimer's Disease: A Bidirectional Relationship." Current Alzheimer Research 18, no. 9 (August 2021): 667–75. http://dx.doi.org/10.2174/1567205018666211124104710.
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Biological rhythms have become the research focus in recent years. Biological rhythm disruption is a common symptom of Alzheimer's disease (AD) patients, which is usually considered as the late consequence of AD. Recent studies have shown that biological rhythm disruption even occurs before the onset of clinical symptoms of AD. The causal relationship between AD and biological rhythm disruption is not clear. Delineating their relationship can help understand the disease mechanisms and make the early diagnosis of AD possible. This review integrates the research on the abnormal changes of the biological rhythm-related parameters in the clinical manifestations of AD patients and the roles of the biological rhythm disorders in AD. We will discuss the links between biological rhythms and AD, with the focus on the bidirectionality between biological rhythms and AD processes. Collectively, these updated research findings may provide the basis for further exploring the significance of rhythm in the diagnosis and treatment of AD.
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Bhuvaneswari, E., B. Sailaja, and S. Sivaprasad. "Impact of photoperiod on circadian sucrose and sucrase rhythms in the digestive system of silkworm, Bombyx mori." Journal of Applied and Natural Science 5, no. 1 (June 1, 2013): 230–41. http://dx.doi.org/10.31018/jans.v5i1.312.
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The impact of photoperiod on circadian sucrose and sucrase rhythms were analyzed in the digestive system of Bombyx mori under 12 hr light-dark cycle (LD), continuous light (LL) and continuous dark (DD). The rhythmic changes were interpreted as synthetic cycles in gut wall and release or uptake cycles in gut lumen. The gut wall comprised 6 sucrose synthetic cycles (SS cycles) under LD, LL and 5 under DD. The 24 hr rhythm of LD and LL was clock shifted to 28.8 hr under DD. In gut content, the sucrose rhythm showed 7 sucrose uptake cycles (SUcycles) under LD, 6 under LL and 5 under DD and the 24 hr rhythm of LD was clock shifted to 28.0 hr under LL and 34 hr under DD. In the gut wall sucrase rhythm maintained 7 SES cycles under LD and DD and 9 cycles under LL and its 24-hr rhythm is advanced to 18.2 hr. In the gut lumen 5 SER cycles under LD, 8 under LL and 6 under DD and its rhythm is advanced to 15 hr under LL and 20 hr under DD. Further analysis of data showed that LD favoured both synthesis and uptake of sucrose while LL, favoured the sucrase synthesis and its release.
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Suzuki, Takako, Makoto Suzuki, Kilchoon Cho, Naoki Iso, Takuhiro Okabe, Toyohiro Hamaguchi, Junichi Yamamoto, and Naohiko Kanemura. "EEG Oscillations in Specific Frequency Bands Are Differently Coupled with Angular Joint Angle Kinematics during Rhythmic Passive Elbow Movement." Brain Sciences 12, no. 5 (May 14, 2022): 647. http://dx.doi.org/10.3390/brainsci12050647.
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Rhythmic passive movements are often used during rehabilitation to improve physical functions. Previous studies have explored oscillatory activities in the sensorimotor cortex during active movements; however, the relationship between movement rhythms and oscillatory activities during passive movements has not been substantially tested. Therefore, we aimed to quantitatively identify changes in cortical oscillations during rhythmic passive movements. Twenty healthy young adults participated in our study. We placed electroencephalography electrodes over a nine-position grid; the center was oriented on the transcranial magnetic stimulation hotspot of the biceps brachii muscle. Passive movements included elbow flexion and extension; the participants were instructed to perform rhythmic elbow flexion and extension in response to the blinking of 0.67 Hz light-emitting diode lamps. The coherence between high-beta and low-gamma oscillations near the hotspot of the biceps brachii muscle and passive movement rhythms was higher than that between alpha oscillation and passive movement rhythm. These results imply that alpha, beta, and gamma oscillations of the primary motor cortex are differently related to passive movement rhythm.
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Dobrescu, Caius. "Drums of Doubt: On the Rhythmical Origins of Poetic and Scientific Exploration." Hungarian Studies Yearbook 1, no. 1 (December 1, 2019): 67–81. http://dx.doi.org/10.2478/hsy-2019-0006.
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Abstract In his article “Drums of Doubt: On the Rhythmical Origins of Poetic and Scientific Exploration” Caius Dobrescu argues that even though the sciences and arts of doubt have never been connected to the notion of rhythm, doubt is a form of energy, and more specifically, a form of vibration. It implies an exploratory movement that constantly expands and recoils in a space essentially experienced as uncharted territory. Poetry acquires cognitive attributes through oscillatory rhythmic patterns that are explorative and adaptive. In order to test this hypothesis, the essay focuses on the nature and functioning of free verse. This modern prosodic mutation brings about a dovetailing of the rhythmic spectrum, but also, and more significantly, a change in the very manner of understanding and experiencing rhythm. Oscillatory rhythms are broadly associable with entrainment indexes that point to the adaptation of inner physiological and behavioral rhythms to oscillatory environment stimuli. Free verse emerges from the experience of regaining an original explorative, adaptive, and orientation-oriented condition of consciousness.
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McKerracher, Adrian. "Towards a Curriculum of Rhythm: Learning at the Speed of Sound." Journal of the Canadian Association for Curriculum Studies 15, no. 2 (December 7, 2017): 8–19. http://dx.doi.org/10.25071/1916-4467.40326.
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This paper examines rhythm and repetition as possibilities for curricular wide-awakeness. When a rhythm is established, an expectation is established with it: patterned beats create momentum, so that subsequent beats arrive to a place that has been prepared by anticipation. But what happens when the rhythm stops? Grounded in the repetition of footsteps that constitute walking, this paper explores how rhythm offers pedagogical possibilities for curricular reconstruction, looking to the way that expectations for the future are informed by habits of listening to the present. It begins by framing the experience of monotony that can cloud sensitivity to daily life. Suggesting that “biographic situations” can be understood as beats in a historical phrase, the paper discusses poly-rhythms as invitations to observe, reflect and participate in the making of (rhythmic) history. Drawing on Deleuze, Pinar and Butler, it emphasizes the productive precarity of rhythm that is imminently falling away into the past, clearing spaces for new possibilities for imagining how circumstances and reactions could be otherwise. It concludes with a call to recognize the complexity of breaking with pre-established patterns of expectation, using sonic experience as practice for the cultivation of historical agency and ontological self-awareness.
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Breska, Assaf, and Leon Y. Deouell. "Automatic Bias of Temporal Expectations following Temporally Regular Input Independently of High-level Temporal Expectation." Journal of Cognitive Neuroscience 26, no. 7 (July 2014): 1555–71. http://dx.doi.org/10.1162/jocn_a_00564.
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Exposure to rhythmic stimulation results in facilitated responses to events that appear in-phase with the rhythm and modulation of anticipatory and target-evoked brain activity, presumably reflecting “exogenous,” unintentional temporal expectations. However, the extent to which this effect is independent from intentional processes is not clear. In two EEG experiments, we isolated the unintentional component of this effect from high-level, intentional factors. Visual targets were presented either in-phase or out-of-phase with regularly flickering colored stimuli. In different blocks, the rhythm could be predictive (i.e., high probability for in-phase target) or not, and the color could be predictive (i.e., validly cue the interval to the target) or not. Exposure to nonpredictive rhythms resulted in faster responses for in-phase targets, even when the color predicted specific out-of-phase target times. Also, the contingent negative variation, an EEG component reflecting temporal anticipation, followed the interval of the nonpredictive rhythm and not that of the predictive color. Thus, rhythmic stimulation unintentionally induced expectations, even when this was detrimental. Intentional usage of predictive rhythms to form expectations resulted in a stronger behavioral effect, and only predictive cues modulated the latency of the target-evoked P3, presumably reflecting stimulus evaluation. These findings establish the existence of unintentional temporal expectations in rhythmic contexts, dissociate them from intentional expectations, and highlight the need to distinguish between the source of expectation (exogenous–endogenous) and the level of voluntary control involved in it (unintentional–intentional).
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Bailey, Michael J., Phillip D. Beremand, Rick Hammer, Deborah Bell-Pedersen, Terry L. Thomas, and Vincent M. Cassone. "Transcriptional Profiling of the Chick Pineal Gland, a Photoreceptive Circadian Oscillator and Pacemaker." Molecular Endocrinology 17, no. 10 (October 1, 2003): 2084–95. http://dx.doi.org/10.1210/me.2003-0121.
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Abstract The avian pineal gland contains both circadian oscillators and photoreceptors to produce rhythms in biosynthesis of the hormone melatonin in vivo and in vitro. The molecular mechanisms for melatonin biosynthesis are largely understood, but the mechanisms driving the rhythm itself or the photoreceptive processes that entrain the rhythm are unknown. We have produced cDNA microarrays of pineal gland transcripts under light-dark and constant darkness conditions. Rhythmic transcripts were classified according to function, representing diverse functional groups, including phototransduction pathways, transcription/translation factors, ion channel proteins, cell signaling molecules, and immune function genes. These were also organized relative to time of day mRNA abundance in light-dark and constant darkness. The transcriptional profile of the chick pineal gland reveals a more complex form of gene regulation than one might expect from a gland whose sole apparent function is the rhythmic biosynthesis of melatonin. The mRNAs encoding melatonin biosynthesis are rhythmic as are many orthologs of mammalian “clock genes.” However, the oscillation of phototransductive, immune, stress response, hormone binding, and other important processes in the transcriptome of the pineal gland, raises new questions regarding the role of the pineal gland in circadian rhythm generation, organization, and avian physiology.
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Takekata, Hiroki, Yu Matsuura, Shin G. Goto, Aya Satoh, and Hideharu Numata. "RNAi of the circadian clock gene period disrupts the circadian rhythm but not the circatidal rhythm in the mangrove cricket." Biology Letters 8, no. 4 (March 7, 2012): 488–91. http://dx.doi.org/10.1098/rsbl.2012.0079.
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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 the circadian and circatidal rhythms of A. asahinai using RNAi. After injection of double-stranded RNA of per , most crickets did not show the circadian modulation of activity but the circatidal rhythm persisted without a significant difference in the period from controls. Thus, per is functionally involved in the circadian rhythm but plays no role, or a less important role, in the circatidal rhythm. We conclude that the circatidal rhythm in A. asahinai is controlled by a circatidal clock whose molecular mechanism is different from that of the circadian clock.
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Anderson, Tatiana M., and Jan-Marino Ramirez. "Respiratory rhythm generation: triple oscillator hypothesis." F1000Research 6 (February 14, 2017): 139. http://dx.doi.org/10.12688/f1000research.10193.1.
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Breathing is vital for survival but also interesting from the perspective of rhythm generation. This rhythmic behavior is generated within the brainstem and is thought to emerge through the interaction between independent oscillatory neuronal networks. In mammals, breathing is composed of three phases – inspiration, post-inspiration, and active expiration – and this article discusses the concept that each phase is generated by anatomically distinct rhythm-generating networks: the preBötzinger complex (preBötC), the post-inspiratory complex (PiCo), and the lateral parafacial nucleus (pFL), respectively. The preBötC was first discovered 25 years ago and was shown to be both necessary and sufficient for the generation of inspiration. More recently, networks have been described that are responsible for post-inspiration and active expiration. Here, we attempt to collate the current knowledge and hypotheses regarding how respiratory rhythms are generated, the role that inhibition plays, and the interactions between the medullary networks. Our considerations may have implications for rhythm generation in general.