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Collective improvisation is remarkable. When peopleimprovise—whether dancing, making music, or conversing—they coordinate their behavior while exploring abstract spacesof movements, sounds, and ideas. How do improvisers navigatethese abstract spaces? One possibility is that improvisationbuilds on foraging strategies used to search the physicalworld. Here, we investigate the dynamics of an especiallycomplex and abstract form of collective improvisation: freejazz. We quantify how professional jazz ensembles navigatea space of sounds and show that it resembles a foraging strategyknown as Area Restricted Search. In particular, ensembleschange their playing dynamics in response to encounters withnovel ‘soundworlds.' Before encountering a new soundworld,ensembles engage in widespread exploration; immediately after,they shift to focused exploitation of the new sound. Whilecollective improvisation pushes at our cognitive limits and is aparadigm of human creativity, it may build on evolutionarilyancientstrategies for searching space.

Aim of this work is to develop the theory of mutual synchronization of two oscillators with hard excitation associated with a delay. Taking into account the delay of a coupling signal is necessary, in particular, when analyzing synchronization at microwave frequencies, when the distance between the oscillators is large compared to the wavelength. Methods. A bifurcation analysis of the mutual synchronization of two generators with hard excitation in the amplitude-phase approximation is carried out. The results of the bifurcation analysis are compared with the results of numerical simulation of the system of differential equations with delay. Results. A complete bifurcation pattern of mutual synchronization on the plane “frequency mismatch — coupling parameter” is presented. In the case of small mismatch and weak coupling, the fixed points, which correspond to modes with dominance of one of the oscillators, merge with saddle fixed points and disappear when the coupling parameter increases. In the case of large mismatch, one of these points either vanishes or loses stability as a result of a subcritical Andronov–Hopf bifurcation. The other of these points remains stable at any values of the coupling parameter, and the oscillation amplitudes of both oscillators gradually equalize and the phase difference tends to zero, i.e., the oscillation mode with dominance of one of the oscillators gradually transforms into the in-phase synchronization mode. It has been found that with an increase in the coupling parameter, a transformation of the basin of attraction of a stable zero fixed point occurs. As a result of this transformation, if at the initial moment of time the oscillations of the generators are close to antiphase, the oscillations decay at any initial amplitudes. Conclusion. The synchronization pattern in the system of delay-coupled oscillators with hard excitation has been studied. It was discovered that in addition to mutual synchronization modes with approximately equal oscillation amplitudes, stationary modes with suppression of oscillations of one generator by another are also possible. The bifurcation mechanisms of the appearance and disappearance of multistability in the system have been examined.

Under the noisy-channel framework of language comprehension, comprehenders infer the speaker's intended meaning by integrating the perceived utterance with their knowledge of the language, the world, and the kinds of errors that can occur in communication. Previous research has shown that, when sentences are improbable under the meaning prior (implausible sentences), participants often interpret them nonliterally. The rate of nonliteral interpretation is higher when the errors that could have transformed the intended utterance into the perceived utterance are more likely. However, previous experiments on noisy channel processing mostly relied on implausible sentences, and it is unclear whether participants' nonliteral interpretations were evidence of noisy channel processing or the result of trying to conform to the experimenter's expectations in an experiment with nonsensical sentences. In the current study, we used the unique properties of Russian, an understudied language in the psycholinguistics literature, to test noisy-channel comprehension using only simple plausible sentences. The prior plausibility of sentences was tied only to their word order; subject-verb-object (SVO) sentences were more probable under the structural prior than object-verb-subject (OVS) sentences. In two experiments, we show that participants often interpret OVS sentences nonliterally, and the probability of nonliteral interpretations depended on the Levenshtein distance between the perceived sentence and the (potentially intended) SVO version of the sentence. The results show that the structural prior guides people's final interpretation, independent of the presence of semantic implausibility.

Prediction is often regarded as an integral aspect of incremental language comprehension, but little is known about the cognitive architectures and mechanisms that support it. We review studies showing that listeners and readers use all manner of contextual information to generate multifaceted predictions about upcoming input. The nature of these predictions may vary between individuals owing to differences in language experience, among other factors. We then turn to unresolved questions which may guide the search for the underlying mechanisms. (i) Is prediction essential to language processing or an optional strategy? (ii) Are predictions generated from within the language system or by domain-general processes? (iii) What is the relationship between prediction and memory? (iv) Does prediction in comprehension require simulation via the production system? We discuss promising directions for making progress in answering these questions and for developing a mechanistic understanding of prediction in language.

Abstract We discuss the oscillations in the elastic pp differential cross section seen in the TOTEM data at $$\sqrt{s}=13$$ s = 13 TeV on the top of the usual smooth behaviour.

Language and music are two human-unique capacities whose relationship remains debated. Some have argued for overlap in processing mechanisms, especially for structure processing. Such claims often concern the inferior frontal component of the language system located within Brocas area. However, others have failed to find overlap. Using a robust individual-subject fMRI approach, we examined the responses of language brain regions to music stimuli, and probed the musical abilities of individuals with severe aphasia. Across 4 experiments, we obtained a clear answer: music perception does not engage the language system, and judgments about music structure are possible even in the presence of severe damage to the language network. In particular, the language regions responses to music are generally low, often below the fixation baseline, and never exceed responses elicited by nonmusic auditory conditions, like animal sounds. Furthermore, the language regions are not sensitive to music structure: they show low responses to both intact and structure-scrambled music, and to melodies with vs. without structural violations. Finally, in line with past patient investigations, individuals with aphasia, who cannot judge sentence grammaticality, perform well on melody well-formedness judgments. Thus, the mechanisms that process structure in language do not appear to process music, including music syntax.

In everyday communication, speakers and listeners make sophisticated inferences about their conversation partner's intended meaning. They combine their knowledge of the visuospatial context with reasoning about the other person's knowledge state and rely on shared assumptions about how language is used to express communicative intentions. However, these assumptions may differ between languages of nonindustrialized-where conversations often primarily take place within a, so-called, society of intimates-and industrialized cultures-societies of strangers. Here, we study inference in communication in the Tsimane', an indigenous people of the Bolivian Amazon, who have little contact with industrialization or formal education. Using a referential communication task, we probe how Tsimane' speakers refer to objects in the world around them when there are potential ambiguities (e.g., referring to a cup when there are multiple cups in view) across different visual contexts. Using an eye-tracking task, we probe the real-time inferences that Tsimane' listeners make about the speaker's intentions. We find that Tsimane' speakers use visual (color, size) contrasts to disambiguate referents (e.g., "Hand me the small cup"), much like English speakers, and they predictively direct their gaze to objects in a contrast set when they hear a modifier (e.g., "small"). Despite myriad cultural and linguistic dissimilarities between the two populations, the qualitative patterns of behavior and eye-gaze of Tsimane' and English speakers were strikingly similar, suggesting that the communicative expectations underlying many everyday inferences may be shared across cultures. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Purpose. The article presents a new method for numerical simulation of quasi-eigenmode oscillations in open resonators of gyrotrons — powerful vacuum generators of electromagnetic waves in the millimeter and submillimeter ranges. The gyrotron cavity has the shape of a weakly inhomogeneous hollow circular metal waveguide. Methods. The proposed approach uses the inhomogeneous string equation with radiation boundary conditions to formulate a nonlinear spectral boundary value problem describing oscillations in a resonator, neglecting the couplings of waves with different radial indices. By linearizing with respect to frequency the radiation boundary conditions, the boundary value problem is reduced to a linear boundary value problem. To discretize this boundary value problem, the finite difference method is used and a linear generalized matrix eigenvalue problem is formulated. This problem is solved by the Arnoldi method with eigenvalues calculation in a shift-invert mode. An iterative algorithm is proposed that makes it possible to sequentially calculate a given number of frequencies and quality factors of quasi-eigenmodes of oscillations. Results. The computer program was developed written in the Wolfram Language and Fortran using the algorithms proposed in the work. The results of test calculations for real gyrotron resonators are presented, which demonstrate the high accuracy of the obtained values of frequencies, quality factors and field distributions of quasi-eigenmode oscillations in the studied resonators. Conclusion. The methods, algorithms and created program proposed in the article can significantly facilitate the process of developing gyrotrons intended for various practical applications and operating in new frequency ranges. The method of iterative refinement of boundary conditions can be generalized to the case of equations of the linear theory of a gyrotron and used to develop new methods for analyzing the starting conditions for the soft self-excitation in gyrotrons — generators.

The quantifier "some" often elicits a scalar implicature during comprehension: "Some of today's letters have checks inside" is often interpreted to mean that not all of today's letters have checks inside. In previous work, Goodman and Stuhlmüller (G&S) proposed a model that predicts that this implicature should depend on the speaker's knowledgeability: If the speaker has only examined some of the available letters (e.g., two of three letters), people are less likely to infer that "some" implies "not all" than if the speaker has examined all of the available letters. G&S also provided behavioral evidence in support of their model. In this paper, we first show that a simple extension of G&S's model (1) predicts G&S's knowledgeability effects, and in addition, (2) predicts that the knowledgeability effect will be reduced when the speaker's usage indicates numeral alternatives are available. We tested the new model's predictions in four preregistered experiments. All experiments supported the first model prediction, replicating G&S's finding of a main effect of the speaker's knowledge. Further, Experiments 2 and 4 supported the second model prediction showing that the words that a speaker tends to use affect the strength of scalar implicature that comprehenders make. In particular, when the speaker has partial knowledge (e.g., has only examined two of three letters), comprehenders think that "some" is more likely to mean "not all" when the speaker also tends to produce number words in similar sentences (e.g., "2 of today's rooms have working smoke detectors."). These results have important ramifications for theories of meaning: the context beyond the sentence (e.g., the speaker's tendency to use particular words) affects the set of alternatives that comprehenders consider when inferring meaning.

Patterns of language use change over time and may reflect and/or impact lexico-semantic representations of individuals as they age. In the current study, we use distributional semantic word embeddings trained on corpora from different decades (HistWords) to examine language change. We first measured lexico-semantic organization in different age groups, using an open dataset of association norms, and tested how they may be related to language change. Then, using the diachronic word embeddings, we sampled English words that have changed in meaning and words that have maintained the same meaning/usage patterns between the 1950s and the 1990s. We tested how relatedness judgments for those words differ when paired with their “neighbors” from earlier vs. recent decades, for both younger and older adults. Our findings suggest that individuals continuously and rapidly update their lexico-semantic representations across the lifespan, such that earlier learned meanings have minimal impact on present-day representation.

Aim of this work is to develop the theory of mutual synchronization of two oscillators with hard excitation associated with a delay. Taking into account the delay of a coupling signal is necessary, in particular, when analyzing synchronization at microwave frequencies, when the distance between the oscillators is large compared to the wavelength. Methods. Theoretical analysis is carried out under the assumption that the delay time is small compared to the characteristic time for the oscillations. The phase approximation is used when the frequency mismatch and the coupling parameter are considered small. Results. Taking into account the change in oscillation amplitudes up to first-order terms in the coupling parameter, a generalized Adler equation for the phase difference of the oscillators is obtained, which takes into account the combined type of the coupling (dissipative and conservative coupling) and non-isochronism. The conditions for saddle-node bifurcations are found and the stability of various fixed points of the system is analyzed. The boundaries of the domains of in-phase and anti-phase synchronization are plotted on the plane of the parameters “frequency mismatch – coupling parameter”. Conclusion. It is shown that, depending on the control parameters (non-isochronism parameter, excitation parameter, phase advance of the coupling signal), the system exhibits behavior typical of either dissipative or conservative coupling. The obtained formulas allow for trace the transition from one type of coupling to another when varying the control parameters.

Spoken language production involves selecting and assembling words and syntactic structures to convey one's message. Here we probe this process by analyzing natural language productions of individuals with primary progressive aphasia (PPA) and healthy individuals. Based on prior neuropsychological observations, we hypothesize that patients who have difficulty producing complex syntax might choose semantically richer words to make their meaning clear, whereas patients with lexicosemantic deficits may choose more complex syntax. To evaluate this hypothesis, we first introduce a frequency-based method for characterizing the syntactic complexity of naturally produced utterances. We then show that lexical and syntactic complexity, as measured by their frequencies, are negatively correlated in a large (n = 79) PPA population. We then show that this syntax-lexicon trade-off is also present in the utterances of healthy speakers (n = 99) taking part in a picture description task, suggesting that it may be a general property of the process by which humans turn thoughts into speech.

In 2023, the Department of Dynamic Systems of Saratov State University on the basis of the Saratov branch of the Institute of Radio Engineering and Electronics of the Russian Academy of Sciences turned 25 years old. During this time, the department prepared training courses "Nonlinear oscillations," "Theory of catastrophes," "Dynamic systems and bifurcations," "Dynamic chaos," "Mathematical methods of nonlinear physics" and others. A series of textbooks and taskbooks in the relevant areas has been released.

Abstract We analyse the cross-section of events with Large Rapidity Gaps observed in proton–lead collisions by the CMS Collaboration ( arXiv:2301.07630 ). The role of the transverse size of elementary pN amplitude is discussed. We emphasize that the cross-section of incoming proton dissociation caused by the photon radiated off the lead ion is close to the value of $$d\sigma /d\Delta \eta ^F$$ d σ / d Δ η F measured by the CMS, and it is not clear why there is no room in the data for the Pomeron-induced contribution

In this paper, the interaction of a monochromatic electromagnetic wave with a counterpropagating electron beam moving in an axial magnetic field is considered. The purpose of this study is to investigate the conditions for occurrence of modulation instability (MI) in such a system and to determine at which parameters of the incident wave the MI is absolute or convective. Methods. Theoretical analysis of the MI character is carried out by studying the asymptotic form of unstable perturbations using the saddle-point analysis. The analytical results are verified by numerical simulations. Results. Theoretically, the boundary of change in the character of MI on the plane of input signal parameters (amplitude and detuning of the frequency from the cyclotron resonance) is determined. Numerical simulations confirm that as the signal frequency increases, the regime of self-modulation, which corresponds to the absolute MI, is replaced by the stationary single-frequency transmission corresponding to the convective MI. The numerical results coincide with the analytical ones for the system, which is matched at the end. The matching is implemented by smooth increasing of the guiding magnetic field in the region of electron beam injection. Conclusion. Determining the analytical conditions for the implementation of the absolute MI is of practical interest, since the emerging self-modulation can lead to the generation of trains of pulses with the spectrum in the form of frequency combs.

Background: Speech of individuals with non-fluent, including Broca’s, aphasia is often characterized as “agrammatic” because their output mostly consists of nouns and, to a lesser extent, verbs and lacks function words, like articles and prepositions, and correct morphological endings. Among the earliest accounts of agrammatic output in the early 1900s was the “economy of effort” idea whereby agrammatic output is construed as a way of coping with increases in the cost of language production. This idea resurfaced in the 1980s, but in general, the field of language research has largely focused on accounts of agrammatism that postulated core deficits in syntactic knowledge. Aims: We here revisit the economy of effort hypothesis in light of increasing emphasis in cognitive science on rational and efficient behavior. Main contribution: The critical idea is as follows: there is a cost per unit of linguistic output, and this cost is greater for patients with non-fluent aphasia. For a rational agent, this increase leads to shorter messages. Critically, the informative parts of the message should be preserved and the redundant ones (like the function words and inflectional markers) should be omitted. Although economy of effort is unlikely to provide a unifying account of agrammatic output in all patients—the relevant population is too heterogeneous and the empirical landscape too complex for any single-factor explanation—we argue that the idea of agrammatic output as a rational behavior was dismissed prematurely and appears to provide a plausible explanation for a large subset of the reported cases of expressive aphasia. Conclusions: The rational account of expressive agrammatism should be evaluated more carefully and systematically. On the basic research side, pursuing this hypothesis may reveal how the human mind and brain optimize communicative efficiency in the presence of production difficulties. And on the applied side, this construal of expressive agrammatism emphasizes the strengths of some patients to flexibly adapt utterances in order to communicate in spite of grammatical difficulties; and focusing on these strengths may be more effective than trying to “fix” their grammar.

According to cross-situational learning, infants aggregate statistical information across naming events to resolve ambiguous word-referent mappings. While lab experiments show that learners are sensitive to these statistics, in studies using naturalistic stimuli, adults often fail to infer the correct referent. Here, we examined how young learners' input “in the wild” differs from laboratory experiments. We analyzed the temporal and spatial regularities of parent naming events in a naturalistic dataset of parent-child play and tested their effect on infants' visual attention. Parents were less likely to name the same toy twice than to name two different toys in sequence, except at short lags (0>t>5s). Most of the visual scenes accompanying naming events were composed of several toys of approximately equal (small) size. Child-attention to the target toy appeared to be modulated primarily by size. These results underscore the importance of quantifying naturalistic statistical regularities for understanding the mechanisms of word learning.

Recent evidence suggests that language processing is well-adapted to noise in the input (e.g., spelling or speech errors, misreading or mishearing) and that comprehenders readily correct the input via rational inference over possible intended sentences given probable noise corruptions. In the current study, we probed the processing of noisy linguistic input, asking whether well-studied ERP components may serve as useful indices of this inferential process. In particular, we examined sentences where semantic violations could be attributed to noise-for example, in "The storyteller could turn any incident into an amusing antidote", where the implausible word "antidote" is orthographically and phonologically close to the intended "anecdote". We found that the processing of such sentences-where the probability that the message was corrupted by noise exceeds the probability that it was produced intentionally and perceived accurately-was associated with a reduced (less negative) N400 effect and an increased P600 effect, compared to semantic violations which are unlikely to be attributed to noise ("The storyteller could turn any incident into an amusing hearse"). Further, the magnitudes of these ERP effects were correlated with the probability that the comprehender retrieved a plausible alternative. This work thus adds to the growing body of literature that suggests that many aspects of language processing are optimized for dealing with noise in the input, and opens the door to electrophysiologic investigations of the computations that support the processing of imperfect input.

We discuss exclusive J/$\psi$ photoproduction, initially in conventional collinear factorisation at NLO and then subsequently in a refined approach with a programme of low x resummation and implementation of a crucial low $Q_0$ subtraction included. We compare and contrast predictions in both frameworks and remark about the possibility to constrain and ultimately determine the low x and low scale gluon PDF, emphasising the significance of this for future global PDF analyses.