Canto e emoção: indicadores emocionais não verbais na execução do discurso musical cantado

Na performance de uma obra musical cantada, o cantor tem um papel determinante para a transmissão ao público, não só das suas componentes informativas, de natureza conceptual, a nível musical e literário, mas também na indução nos ouvintes dos estados emocionais intrínsecos a cada momento da obra através de indicadores vocais não verbais. Este estudo teve como objectivo central a análise dos parâmetros acústicos que constituem estes indicadores e a sua eficácia. Procurou-se estabelecer uma relação entre as alterações fisiológicas que caracterizam os processos somáticos que acompanham o despoletar dos estados emocionais e os perfis acústicos das vocalizações produzidas nessas condições, partindo de uma reflexão sobre o cantor e a sua função social, passando pela análise do fenómeno da emoção como parte integrante da biologia do indivíduo e da espécie. O grau de indução emocional no público depende da capacidade de o cantor integrar os processos de expressão da emoção na sua execução musical, reflectindo no perfil acústico daí resultante não só a qualidade da sua técnica e as suas características vocais, mas também as alterações fisiológicas que acompanham a libertação de neurotransmissores e neuromoduladores, as modificações na expressão facial, na forma e grau de tensão do tracto vocal, ou no perfil respiratório. Este mecanismo utiliza o relacionamento entre sinais sonoros e estados emocionais do emissor e do receptor processado através de um grupo específico de neurónios, os neurónios de espelho. Para caracterizar os indicadores acústicos dos estados emocionais mais simples, foi elaborado um conjunto de parâmetros, aplicados na análise de vocalizações recolhidas em situações emocionais induzidas. Os cantores que colaboraram no presente estudo passaram pelo mesmo processo, e os seus parâmetros foram comparados com os do paradigma estabelecido. O grau de compatibilidade com a norma foi medido por um índice onde se valorizaram os parâmetros mais significativos. Estes resultados foram posteriormente aferidos com os de testes onde se procurou determinar o grau de identificação pelo público dos sinais acústicos portadores de sentido emocional em exemplos musicais cantados. Destes, foram seleccionados aqueles que atingiram os níveis de identificação acima de 90% e os inferiores a 50%, procedendo-se à análise dos parâmetros acústicos de segmentos particularmente relevantes extraídos desses exemplos, para definir aqueles que se mostraram decisivos para a escolha do público.

Psycho-physio dynamics in violin-piano duo: a pianist's perspective

The case study looked at psychological and physiological responses to stress in musicians, comparing a newly formed and a consolidated violin-piano duo. The common element between these duos was the pianist. Using the psychological tests (STAI Y1 and Y2, K-MPAI, MMPI-2, ICAC), the immunoassay saliva test to measure cortisol (stress hormone) and non- invasive device VitalJacket® developed at the University of Aveiro, Portugal, participants were monitored under various performance conditions. Others quantitative and qualitative dataset were collected including a pianist’s personal diary (analyzed by psychiatrist), semi-structured interviews with members of long-terms chamber music duo and perceptual evaluations (listening test) of the performances by expert listeners. The variables included two performance venues (European university and secondary school), as well as well-known repertoire, recently known repertoire and newly known repertoire. The latter was given approximately one week before each recital. The psychological and physiological dataset were collected for a total of eight recitals – two series of four recitals each. The unexpected results show that state anxiety levels and stress of the pianist, who does not present an anxious profile, either in social or in musical terms, are always higher when playing with a well-known partner. Possible explanations may be due to the highest expectations for quality of performance and implications of mirror neurons (since the reactions are very different according to the partner). In other words, the “known” (i.e., the consolidated duo) can become “trapped” within a predetermined space, especially at the psychological level, while the “unknown” (the occasional duo) seems to be less involved and therefore more reassuring and exciting in positive terms. In addition, the preference of the expert audience is for the consolidated duo.

Functional analysis of String/CDC25 phosphatase in post-mitotic neurons

Cell cycle and differentiation are two highly coordinated processes during organ development. Recent studies have demonstrated that core cell cycle regulators also play cell cycle-independent functions in post-mitotic neurons, and are essential for the maintenance of neuronal homeostasis. CDC25 phosphatases are well-established CDK activators and their activity is mainly associated to proliferating tissues. The expression and activity of mammalian CDC25s has been reported in adult brains. However, their physiological relevance and the potential substrates in a non-proliferative context have never been addressed. string (stg) encodes the Drosophila CDC25 homolog. Previous studies from our group showed that stg is expressed in photoreceptors (PRs) and in lamina neurons, which are two differentiated cell types that compose the fly visual system. The aims of this work are to uncover the function of stg and to identify its potential neuronal substrates, using the Drosophila visual system as a model. To gain insight into the function of stg in a non-dividing context we used the GAL4/UAS system to promote downregulation of stg in PR-neurons, through the use of an RNAi transgene. The defects caused by stg loss-of-function were evaluated in the developing eye imaginal disc by immunofluorescence, and during adult stages by scanning electron microscopy. This genetic approach was combined with a specific proteomic method, two-dimensional difference gel electrophoresis (2D-DIGE), to identify the potential substrates in PR-cells. Our results showed that stg downregulation in PRs affects the well-patterned retina organization, inducing the loss of apical maintenance of PR-nuclei on the eye disc, and ommatidia disorganization. We also detected an abnormal accumulation of cytoskeletal proteins and a disruption of the axon structure. As a consequence, the projection of PR-axons into the lamina and medulla neuropils of the optic lobe was impaired. Upon stg downregulation, we also detected that PR-cells accumulate Cyclin B. Although the rough eye phenotype observed upon stg downregulation suggests neurodegeneration, we did not detect neuronal death during larval stages, suggesting that it likely occurs during pupal stages or during adulthood. By 2D-DIGE, we identified seven proteins which were differentially expressed upon stg downregulation, and are potential neuronal substrates of Stg. Altogether, our observations suggest that Stg phosphatase plays an essential role in the Drosophila visual system neurons, regulating several cell components and processes in order to ensure their homeostasis.