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Din sökning på "kognition" gav 1815 sökträffar

Nonlinear phenomena make animal calls alarming for human listeners

Animal vocalizations are extremely diverse, and evolutionary approaches to understanding this diversity assume some mapping between their acoustic form and communicative function, with specific features serving universal roles. Here, we investigate whether irregular vocal production with nonlinear phenomena contrib-utes to the alarming quality of vertebrate calls. We resynthesized 98 calls of bird

Correlates of Vocal Tract Evolution in Late Pliocene and Pleistocene Hominins

Despite decades of research on the emergence of human speech capacities, an integrative account consistent with hominin evolution remains lacking. We review paleoanthropological and archaeological findings in search of a timeline for the emergence of modern human articulatory morphological features. Our synthesis shows that several behavioral innovations coincide with morphological changes to the

Chants across seven traditions share acoustic traits that enhance subjective relaxation

For over 5,000 y, chanting has been practiced across many Western and Eastern traditions. However, there is hardly any empirical research on 1) whether chants from across the globe share common acoustic properties, 2) whether these acoustic features make them distinct from other human vocalizations, and 3) the extent to which they may positively impact listeners’ well-being. Here, we collected 242

Rhythmic parameters and lateralisation in the percussive behaviour of Japanese Macaques (Macaca fuscata)

Japanese macaques (Macaca fuscata) exhibit a suite of stone handling behaviours (SHB, e.g. rolling, pounding, etc.) that lack an obvious instrumental function. As SHBs appear to be socially transmitted, previous research has focused on evolutionary theories of tool use and cumulative culture. It has been assumed that SHBs in general represent a form of solitary play whose function is to hone and m

Differences Teach Us More Than Similarities : The Need for Evolutionary Thinking in Comparative Cognition

A persistent anthropocentric school of thought prevents comparative cognition from truly joining the evolutionary sciences, which often view “cognition” as an alien subject to the study of life. In this article, I argue that cognition is indeed inherent to all life and that we could study the evolution of cognitive skills like any other species-specific trait if we stop elevating convergence over

Cognitive Control in Distracted Dinosaurs

Cognitive control is a skill used to control one’s own behaviour to reach a goal. We compared this skill across archosaurs by using the distraction task on American alligators, emus, chickens, and common ravens. We investigated whether the animals would still find a food reward hidden behind one of two identical opaque barriers after picking up a food distraction. Results show that all species can

Acoustic estimation of voice roughness

Roughness is a perceptual characteristic of sound that was first applied to musical consonance and dissonance, but it is increasingly recognized as a central aspect of voice quality in human and animal communication. It may be particularly important for asserting social dominance or attracting attention in urgent signals such as screams. To ensure that the results of roughness research are valid a

Thought for food : the endothermic brain hypothesis

The evolution of whole-body endothermy occurred independently in dinosaurs and mammals and was associated with some of the most significant neurocognitive shifts in life's history. These included a 20-fold increase in neurons and the evolution of new brain structures, supporting similar functions in both lineages. We propose the endothermic brain hypothesis, which holds that elaborations in endoth

How to analyse and manipulate nonlinear phenomena in voice recordings

We address two research applications in this methodological review: starting from an audio recording, the goal may be to characterize nonlinear phenomena (NLP) at the level of voice production or to test their perceptual effects on listeners. A crucial prerequisite for this work is the ability to detect NLP in acoustic signals, which can then be correlated with biologically relevant information ab

Acoustic context and dynamics of nonlinear phenomena in mammalian calls : the case of puppy whines

Nonlinear phenomena (NLP) are often associated with high arousal and function to grab attention and/or signal urgency in vocalizations such as distress calls. Although biomechanical models and in vivo/ex vivo experiments suggest that their occurrence reflects the destabilization of vocal fold vibration under intense subglottal pressure and muscle tension, comprehensive descriptions of the dynamics

Nonlinear vocal phenomena and speech intelligibility

At some point in our evolutionary history, humans lost vocal membranes and air sacs, representing an unexpected simplification of the vocal apparatus relative to other great apes. One hypothesis is that these simplifications represent anatomical adaptations for speech because a simpler larynx provides a suitably stable and tonal vocal source with fewer nonlinear vocal phenomena (NLP). The key assu

Nonlinear phenomena in vertebrate vocalizations : mechanisms and communicative functions

Nonlinear phenomena (NLP) are acoustic irregularities that are widespread in animal and human vocal repertoires, as well as in music. These phenomena have recently attracted considerable interest but, surprisingly, have never been the subject of a comprehensive review. NLP result from irregular sound production, contribute to perceptual harshness, and have long been considered nonadaptive vocal fe

Formant analysis of vertebrate vocalizations : achievements, pitfalls, and promises

When applied to vertebrate vocalizations, source-filter theory, initially developed for human speech, has revolutionized our understanding of animal communication, resulting in major insights into the form and function of animal sounds. However, animal calls and human nonverbal vocalizations can differ qualitatively from human speech, often having more chaotic and higher-frequency sources, making

A practical guide to calculating vocal tract length and scale-invariant formant patterns

Formants (vocal tract resonances) are increasingly analyzed not only by phoneticians in speech but also by behavioral scientists studying diverse phenomena such as acoustic size exaggeration and articulatory abilities of non-human animals. This often involves estimating vocal tract length acoustically and producing scale-invariant representations of formant patterns. We present a theoretical frame

Why do people make noises in bed?

Many primates produce copulation calls, but we have surprisingly little data on what human sex sounds like. I present 34 h of audio recordings from 2239 authentic sexual episodes shared online. These include partnered sex or masturbation, but each recording has only one main vocalizer (1950 female, 289 male). Both acoustic features and arousal ratings from an online perceptual experiment with 109

The role of loudness in vocal intimidation

Across many species, a major function of vocal communication is to convey formidability, with low voice frequencies traditionally considered the main vehicle for projecting large size and aggression. Vocal loudness is often ignored, yet it might explain some puzzling exceptions to this frequency code. Here we demonstrate, through acoustic analyses of over 3,000 human vocalizations and four percept

Vocal communication : The enigmatic production of low-frequency purrs in cats

Cat purring, the unusual, pulsed vibration that epitomizes comfort, enjoys a special status in the world of vocal communication research. Indeed, it has long been flagged as a rare exception to the dominant theory of voice production in mammals. A new study presents histological and biomechanical evidence that purring can occur passively, without needing muscle vibration in the larynx controlled b

Cognitive functioning in adolescents with severe obesity undergoing bariatric surgery or intensive non-surgical treatment in Sweden (AMOS2): a multicentre, open-label, randomised controlled trial

Severe obesity during childhood is associated with cognitive deficits. Studies in adults have suggested improvements in executive functioning and memory after bariatric surgery. Our aim was to explore changes in cognitive function in adolescents over two years after bariatric surgery or intensive non-surgical treatment. Methods: The Adolescent Morbid Obesity Surgery 2 (AMOS2) is a multicentre, ope

Development of semantic verbal fluency and narrative ability during summer vacation versus formal schooling

The detrimental effect of a lengthy summer vacation on important scholastic abilities such as reading, writing and mathematical skills is relatively well documented, but how language skills are affected by summer vacation is less investigated. The purpose of our study is to investigate how lexical organization and retrieval assessed by a semantic verbal fluency (SVF) task and oral narrative abilit