Towards Biological Plausibility of Vocal Learning Models: a Short Review

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A bio-inspired model towards vocal gesture learning in songbird

Corresponding code at https://github.com/spagliarini/2018-ICDL-EPIROBInternational audienceThe paper proposes a bio-inspired model for an imitative sensorimotor learning, which aims at building a map between the sensory representations of gestures (sensory targets) and their underlying motor pattern through random exploration of the motor space. An example of such learning process occurs during vocal learning in humans or birds, when young subjects babble and learn to copy previously heard adult vocalizations. Previous work has suggested that a simple Hebbian learning rule allows perfect imitation when sensory feedback is a purely linear function of the motor pattern underlying movement production. We aim at generalizing this model to the more realistic case where sensory responses are sparse and non-linear. To this end, we explore the performance of various learning rules and nor-malizations and discuss their biological relevance. Importantly, the proposed model is robust whatever normalization is chosen. We show that both the imitation quality and the convergence time are highly dependent on the sensory selectivity and dimension of the motor representation

Vocal Imitation in Sensorimotor Learning Models: a Comparative Review

International audienceSensorimotor learning represents a challenging problem for natural and artificial systems. Several computational models have been proposed to explain the neural and cognitive mechanisms at play in the brain. In general, these models can be decomposed in three common components: a sensory system, a motor control device and a learning framework. The latter includes the architecture, the learning rule or optimisation method, and the exploration strategy used to guide learning. In this review, we focus on imitative vocal learning, that is exemplified in song learning in birds and speech acquisition in humans. We aim to synthesise, analyse and compare the various models of vocal learning that have been proposed, highlighting their common points and differences. We first introduce the biological context, including the behavioural and physiological hallmarks of vocal learning and sketch the neural circuits involved. Then, we detail the different components of a vocal learning model and how they are implemented in the reviewed models

Canary Vocal Sensorimotor Model with RNN Decoder and Low-dimensional GAN Generator

International audienceSongbirds, like humans, learn to imitate sounds produced by adult conspecifics. Similarly, a complete vocal learning model should be able to produce, perceive and imitate realistic sounds. We propose (1) to use a low-dimensional generator model obtained from training WaveGAN on a canary vocalizations, (2) to use a RNN-classifier to model sensory processing. In this scenario, can a simple Hebbian learning rule drive the learning of the inverse model linking the perceptual space and the motor space? First, we study how the motor latent space topology affects the learning process. We then investigate the influence of the learning rate and of the motor latent space dimension. We observe that a simple Hebbian rule is able to drive the learning of realistic sounds produced via a low-dimensional GAN

Learning an inverse model for vocal production: toward a bio-inspired model

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What does the Canary Say? Low-Dimensional GAN Applied to Birdsong

The generation of speech, and more generally com- plex animal vocalizations, by artificial systems is a difficult problem. Generative Adversarial Networks (GANs) have shown very good abilities for generating images, and more recently sounds. While current GANs have high-dimensional latent spaces, complex vocalizations could in principle be generated through a low-dimensional latent space, easing the visualization and evaluation of latent representations. In this study, we aim to test the ability of a previously developed GAN, called WaveGAN, to reproduce canary syllables while drastically reducing the latent space dimension. We trained WaveGAN on a large dataset of canary syllables (16000 renditions of 16 different syllable types) and varied the latent space dimensions from 1 to 6. The sounds produced by the generator are evaluated using a RNN- based classifier. This quantitative evaluation is paired with a qualitative evaluation of the GAN productions across training epochs and latent dimensions. Altogether, our results show that a 3-dimensional latent space is enough to produce all syllable types in the repertoire with a quality often indistinguishable from real canary vocalizations. Importantly, we show that the 3-dimensional GAN generalizes by interpolating between the various syllable types. We rely on UMAP [1] to qualitatively show the similarities between training and generated data, and between the generated syllables and the interpolations produced. We discuss how our study may provide tools to train simple models of vocal production and/or learning. Indeed, while the RNN- based classifier provides a biologically realistic representation of the auditory network processing vocalizations, the small dimensional GAN may be used for the production of complex vocal repertoires

Epidemiologia dos acidentes ofídicos registrados na vigilância epidemiológica no município de Rio Verde – Goiás, Brasil

The present study aimed to evaluate the cases of snakebites registered in the municipality of Rio Verde-GO, Brazil, between january 2007 and november 2010. Data collected by the Notifiable Diseases Information System - Ministry of Health at epidemiological surveillance of the municipality. The results obtained were organized based on the number of accidents, gender of the snake, circumstance of the accident, monthly and annual distribution, seasonality distribution, age group and sex of the individuals, affected anatomical region, time elapsed from the accident/care, evolution or clinical picture and classification by severity. Ophidian accidents were caused by the genera Bothrops, Crotalus, Micrurus and ignored cases, totaling 89 accidents. The highest rate of accidents was with the genus Bothrops (17) and 20 ignored cases, where it was not possible to identify the species. There was a predominance of accidents in the months between december to march (hot and rainy season) with 46 cases (64.05%). Most accidents occurred in the countryside with 75 cases. Records predominated in males (68 cases) and aged 11-29 years. The anatomical region most affected were legs and feet. The time elapsed between the accident and the service prevailed between 1 and 2 hours, where 86.51% of the cases evolved to cure. There were no death records, and 20.22% of the cases were classified as mild and 58.42% as moderate. In conclusion, the results obtained in this study are in line with other studies presented. Ophidian accidents are still a public health problem in Brazil, and data are still scarce in order to understand the severity and establish protocols with greater agility and in a shorter time between ophidism and healing.El presente estudio tuvo como Objetivo, evaluar los casos de mordeduras de serpiente registrados en la ciudad de Rio Verde-GO, Brasil, entre enero de 2007 y noviembre de 2010. Datos recopilados por el Sistema de Información de Enfermedades de Declaración Obligatoria - Ministerio de Salud en vigilancia epidemiológica del municipio. Los resultados obtenidos se organizaron en base al número de accidentes, sexo de la serpiente, circunstancia del accidente, distribución mensual y anual, distribución estacional, grupo de edad y sexo de los individuos, región anatómica afectada, tiempo transcurrido desde el accidente/cuidado, evolución o condición clínica y clasificación por gravedad. Las mordeduras de serpientes fueron causadas por los géneros Bothrops, Crotalus, Micrurus y se ignoraron los casos, totalizando 89 accidentes. La mayor tasa de accidentes fue con el género Bothrops (17) y 20 casos ignorados, donde no fue posible identificar la especie. Hubo predominio de accidentes en los meses entre diciembre y marzo (temporada de calor y lluvias) con 46 casos (64,05%). La mayoría de los accidentes ocurrieron en áreas rurales con 75 casos. Predominaron los registros en el sexo masculino (68 casos) y de 11 a 29 años. La región anatómica más afectada fueron piernas y pies. El tiempo transcurrido entre el accidente y la atención predominó entre 1 a 2 horas, donde el 86,51% de los casos evolucionaron a curación. No hubo registros de muertes, y el 20,22% de los casos se clasificaron como leves y el 58,42% como moderados. En conclusión, los resultados obtenidos en este estudio están en concordancia con otros trabajos presentados. Las mordeduras de serpientes siguen siendo un problema de salud pública en Brasil, y los datos aún son escasos para comprender la gravedad y establecer protocolos con mayor agilidad y en un tiempo más corto entre la mordedura de serpiente y la curación.O presente estudo objetivou-se avaliar, os casos de acidentes ofídicos registrados no município de Rio Verde-GO, Brasil, entre janeiro de 2007 a novembro de 2010. Foram analisados dados coletados pelo Sistema de Informação de Agravos de Notificação - Ministério da Saúde na vigilância epidemiológica do município. Os resultados obtidos foram organizados com base no número de acidentes, gênero da serpente, circunstância do acidente, distribuição mensal e anual, distribuição sazonalidade, faixa etária e sexo dos indivíduos, região anatômica atingida, tempo decorrido do acidente/atendimento, evolução ou quadro clínico e classificação quanto à gravidade. Os acidentes ofídicos foram causados pelos gêneros Bothrops, Crotalus, Micrurus e casos ignorados, totalizando 89 acidentes. O maior índice de acidentes foi com o gênero Bothrops (17) e 20 casos ignorados, onde não foi possível identificar a espécie. Houve predomínio dos acidentes nos meses entre dezembro a março (estação quente e chuvosa) com 46 casos (64,05%). A maioria dos acidentes ocorreu na zona rural com 75 casos. Os registros predominaram em pessoas do sexo masculino (68 casos) e com idades entre 11-29 anos. A região anatômica mais atingida foram pernas e pés. O tempo decorrido entre o acidente e o atendimento prevaleceu entre 1 a 2 horas, onde 86,51% dos casos evoluíram para cura. Não houve registros de óbitos, e 20,22% dos casos tiveram classificação de nível leve e 58,42% de nível moderado. Concluindo, os resultados obtidos neste estudo estão em conformidade com outros trabalhos apresentados. Os acidentes ofídicos ainda constituem um problema de saúde pública no Brasil, e os dados ainda são escassos para que se possa entender a gravidade e estabelecer protocolos com maior agilidade e em menor tempo entre o ofidismo e a cura

VIOLÊNCIA FAMILIAR: A REALIDADE DOS MORADORES DE UM BAIRRO DE MARINGÁ

Trata-se de uma pesquisa exploratória descritiva desenvolvida num bairro da periferia de Maringá, Paraná, em janeiro de 2000. Teve por objetivo verificar a presença de violência intrafamiliar, identificar suas principais causas e suas maiores vítimas. Verificamos que 62% dos entrevistados eram economicamente ativos, 74% foram mulheres, 16% eram analfabetos, 55% vivenciaram a violência dentro das famílias. Os tipos de violência intrafamiliar que mais se sobressaíram foram a verbal e a física; os agressores em sua maioria eram homens, pai 33% e marido 25%, e as vítimas mulheres e crianças. As principais causas da violência eram bebida 20% e desentendimento 15%; a atitude frente a agressão foi de não reagir 27% ou enfrentar 32%; 62% procuraram ajuda após a agressão e destes 47% buscaram a policia. Concluímos que é importante caracterizar e demonstrar a violência no município, para que assim possamos sensibilizar profissionais e a comunidade sobre esta realidade

Doença hemolítica do recém-nascido devido a anti-U

Anti-U is a rare red blood cell alloantibody that has been found exclusively in blacks. It can cause hemolytic disease of the newborn and hemolytic transfusion reactions. We describe the case of a female newborn presenting a strongly positive direct antiglobulin test due to an IgG antibody in cord blood. Anti-U was recovered from cord blood using acid eluate technique. Her mother presented positive screening of antibodies with anti-U identified at delivery. It was of IgG1 and IgG3 subclasses and showed a titer of 32. Monocyte monolayer assay showed moderate interaction of Fc receptors with maternal serum with a positive result (3.1%). The newborn was treated only with 48 hours of phototherapy for mild hemolytic disease. She recovered well and was discharged on the 4th day of life. We conclude that whenever an antibody against a high frequency erythrocyte antigen is identified in brown and black pregnant women, anti-U must be investigated.Anti-U é um aloanticorpo eritrocitário raro detectado exclusivamente em negros, que pode causar doença hemolítica do recém-nascido e reações transfusionais hemolíticas. Relatamos o caso de um recém-nascido, de sexo feminino, que apresentou teste de antiglobulina direto fortemente positivo, dirigido a um anticorpo IgG em sangue de cordão umbilical. Anti-U foi identificado por técnica de eluição ácida. A mãe apresentava pesquisa de anticorpos irregulares positiva com anticorpo anti-U, de subclasses IgG1 e IgG3, título 32, identificado ao nascimento. O ensaio de monocamada de monócitos apresentou resultado positivo (3.1%), mostrando uma interação moderada de receptores Fc com soro materno. O recém-nascido foi tratado somente por fototerapia durante 48 horas para uma doença hemolítica leve. A criança recuperou-se bem e teve alta médica no quarto dia de vida. Concluímos que quando um anticorpo contra um antígeno eritrocitário de alta freqüência for identificado em gestantes negras e pardas, anti-U deve ser investigado

Melatonin reshapes the mitochondrial network and promotes intercellular mitochondrial transfer via tunneling nanotubes after ischemic-like injury in hippocampal HT22 cells

Mitochondrial dysfunction is considered one of the hallmarks of ischemia/reperfusion injury. Mitochondria are plastic organelles that undergo continuous biogenesis, fusion, and fission. They can be transferred between cells through tunneling nanotubes (TNTs), dynamic structures that allow the exchange of proteins, soluble molecules, and organelles. Maintaining mitochondrial dynamics is crucial to cell function and survival. The present study aimed to assess the effects of melatonin on mitochondrial dynamics, TNT formation, and mitochondria transfer in HT22 cells exposed to oxygen/glucose deprivation followed by reoxygenation (OGD/R). The results showed that melatonin treatment during the reoxygenation phase reduced mitochondrial reactive oxygen species (ROS) production, improved cell viability, and increased the expression of PGC1α and SIRT3. Melatonin also preserved the expression of the membrane translocase proteins TOM20 and TIM23, and of the matrix protein HSP60, which are involved in mitochondrial biogenesis. Moreover, it promoted mitochondrial fusion and enhanced the expression of MFN2 and OPA1. Remarkably, melatonin also fostered mitochondrial transfer between injured HT22 cells through TNT connections. These results provide new insights into the effect of melatonin on mitochondrial network reshaping and cell survival. Fostering TNTs formation represents a novel mechanism mediating the protective effect of melatonin in ischemia/reperfusion injury