Browsing by Author "Silva, Carlos Fernandes da"
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- Adult attachment style and cortisol responses in women in late pregnancyPublication . Martins, José Manuel Costa; Ramos, Mariana Moura; Cascais, Maria João; Silva, Carlos Fernandes da; Martins, Henriqueta Maria Ramalhinho Ginja da Costa; Pereira, Marco Daniel de Almeida; Coelho, Rui Manuel Bento de Almeida; Tavares, Jorge MergulhãoBackground: Recent research has documented the association between attachment and cortisol rhythms. During pregnancy, when attachment patterns are likely to be activated, elevated levels of cortisol are associated with negative effects for the mother and the foetus. The aim of the present study was to examine the association of adult attachment style and cortisol rhythms in pregnant women. Methods: Eighty women in the third trimester of pregnancy participated in the study. Adult attachment was assessed using the Adult Attachment Scale–Revised (AAS-R). Participants collected 4 samples of salivary cortisol at two different days; 3 samples were collected in the morning immediately after wakeup and one sample was collected by bedtime. Results:Results found group significant differences in the cortisol diurnal oscillation ( F (1,71) = 26.46, p < .001,), with secure women reporting a steep decrease in cort isol from awakening to bedtime, while women with fearful avoidant attachment reported no changes. No group differences were found regarding the cortisol awakening response. Conclusions: These results highlight the importance of consi dering attachment patterns during pregnancy, suggesting fearful avoidant attachment style as a possible risk factor for emotional difficulties and dysregulation of the neuroendocrine rhythms.
- An automatic classifier of emotions built from entropy of noisePublication . Ferreira, Jacqueline; Brás, Susana; Silva, Carlos Fernandes da; Soares, Sandra Cristina de OliveiraThe electrocardiogram (ECG) signal has been widely used to study the physiological substrates of emotion. However, searching for better filtering techniques in order to obtain a signal with better quality and with the maximum relevant information remains an important issue for researchers in this field. Signal processing is largely performed for ECG analysis and interpretation, but this process can be susceptible to error in the delineation phase. In addition, it can lead to the loss of important information that is usually considered as noise and, consequently, discarded from the analysis. The goal of this study was to evaluate if the ECG noise allows for the classification of emotions, while using its entropy as an input in a decision tree classifier. We collected the ECG signal from 25 healthy participants while they were presented with videos eliciting negative (fear and disgust) and neutral emotions. The results indicated that the neutral condition showed a perfect identification (100%), whereas the classification of negative emotions indicated good identification performances (60% of sensitivity and 80% of specificity). These results suggest that the entropy of noise contains relevant information that can be useful to improve the analysis of the physiological correlates of emotion.
- Assessment effectiveness for second language learners : Predictors, reliability and discriminant profilesPublication . Figueiredo, Sandra; Martins, Margarida Alves; Silva, Carlos Fernandes daThe main concerns that enhance the empirical studies in assessment of second language learners is to identify the prevalence of second language deficits, the validity of a new test, and to determine specificities and predictors of speakers’ profiles, among other variables (age, home language formal instruction, exposure to second language, first years of schooling, nationality, parent’s profiles). Hypotheses: different language speakers will perform differently in specific tasks in portuguese language, so age, home language, and first language instruction would be main predictors? Strong discriminant achievements could be identified in percentiles 25 and 75? In this post-doctoral research the main goal is to assess new immigrant students from several Portuguese schools to determine cognitive and linguistic profiles. Through new diagnostic test in second language area will be analyzed distinct verbal behaviors and determined cut-offs. Additionally will be evaluated the difficulty and reliability of each task. Method: the instrument was developed with 15 tasks based on international assessment sources such Alberta, TOEFL, DELNA and WMLSR. There is no knowledge of other validated tools to test portuguese immigrant students. Approximately 110 individuals were assessed, with ages between 7 and 17 years old, speakers of romance, indo-aryan, afro-asiatic, slavic, and mandarin languages, and at this phase we are conducting inferential tests (SPSS) to measure profiles and reliability coefficients. The collection of sample is still ongoing. Findings: in one hand, this paper reports preliminary data gathered from a large-scale district study that is examining language proficiency and cognitive performance of immigrants in Portuguese schools. Different language speakers and age groups, with different amounts of instruction in home language, from basic and high schools, will be analyzed regarding lowest and highest performances in picture-naming (1) and semantic relations tasks (2), particularly focusing the vocabulary decoding skills. Findings demonstrate reliable tasks and different student’s profiles, being crucial over proficiency levels identification. In the other hand, prior findings in this area will be expected to be confirmed such as the influence of age and mother tongue. Part of our hypotheses will be rejected considering the youngest learner’s low scores and the creoles language speakers with deficits in specific vocabulary domain. Particular assumptions of literature in this area will be discussed regarding divergent data observed and new insights. Older learners, with instruction in first language, speakers of slavic, mandarin and romance languages presented more positive results and expected greater cognitive profile in second language specific traits. But, other variables should be considered with further examination and with the conclusion of the empirical study. Also implications of results and test feasibility will be discussed for general educational policies and assessment in second language field.
- Beware the serpent: The advantage of ecologically-relevant stimuli in accessing visual awarenessPublication . Gomes, Nuno; Silva, Samuel; Silva, Carlos Fernandes da; Soares, Sandra Cristina de OliveiraSnakes and spiders constitute fear-relevant stimuli for humans, as many species have deleterious and even fatal effects. However, snakes provoked an older and thus stronger evolutionary pressure than spiders, shaping the vision of earliest primates toward preferential visual processing, mainly in the most complex perceptual conditions. To the best of our knowledge, no study has yet directly assessed the role of ecologically-relevant stimuli in preferentially accessing visual awareness. Using continuous flash suppression (CFS), the present study assessed the role of evolutionary pressure in gaining a preferential access to visual awareness. For this purpose, we measured the time needed for three types of stimuli - snakes, spiders (matched with snakes for rated fear levels, but for which an influence on humans but not other primates is well grounded) and birds - to break the suppression and enter visual awareness in two different suppression intensity conditions. The results showed that in the less demanding awareness access condition (stimuli presented to the participants' dominant eye) both evolutionarily relevant stimuli (snakes and spiders) showed a faster entry into visual awareness than birds, whereas in the most demanding awareness access condition (stimuli presented to the participants' non-dominant eye) only snakes showed this privileged access. Our data suggest that the privileged unconscious processing of snakes in the most complex perceptual conditions extends to visual awareness, corroborating the proposed influence of snakes in primate visual evolution.
- Cognitive systems evolution: Immigrant last generations and cognitive mapping changingPublication . Figueiredo, Sandra; Martins, Margarida Alves; Silva, Carlos Fernandes daThere is little evidence on the correlation between immigration effects and the evolution of the mind and cognition, especially concerning children. Last generations of young immigrants are expected to experience adaptive strategies to respond to the school environment in order to achieve success. Specifically concerning the new language learning in the diversity of the host countries (plus the diversity of the countries of origin and home languages/cultures), it should be analyzed how the human cognitive aptitude (language aptitude and problem solving) is being reorganized in terms of thought, concepts and cultural orientations previously developed in a certain native culture. The native culture (aspects of the nationality and of the home language) is mentally associated to concepts and generates the self-regulation which implies consciousness in a home culture as a reference. How does it works for new immigrants that were separated (including cases of forced immigration) from their unique cognitive reference? Different cognitive achievements and language deficits would be constrained in their natural development and differences in academic achievement are expected. This lead to implications for the biological hypothesis of critical period concerning the new waves of immigration and ethnic differentiation in current generations. Age would be considered along with other unexpected variables such as nationality. The present study examines populations’ differences – ethnic and age – on specific language and cognitive tasks considering immigrant students in Portuguese schools (M=13 years old; SD= 2,7) with origin in different world areas: Western Europe, Eastern Europe, African countries, Latin America, Asia (Indian Asia) and China and with different home languages and cultures. Data showed a variability of groups’ achievements in cognates, text recall, lexical recall and dichotic listening tasks. Disparities among the minorities will be discussed considering educational and ethological implications. Population evolutionary characteristics might be concluded from those disparities.
- Desenvolvimento curricular e didáticaPublication . Figueiredo, Sandra; Silva, Carlos Fernandes da; Martins, Margarida AlvesO “comportamento verbal” concretiza-se porque, por um lado, existe um sistema de princípios e condições que por si só são considerados os elementos inerentes a todas as línguas naturais, determinados pela necessidade biológica, mas, por outro lado, esses elementos integram uma relação dinâmica de eventos que constituem o contexto do sujeito. Os eventos não se restringem às estruturas cerebrais (a perspetiva mentalista), mas também a aspetos externos e que se apresentam como conjunto de estímulos a ser discriminado- meio ambiente (a perspetiva funcional). Após uma breve revisão teórica de conceitos e de processos de descodificação fonética, serão apresentados resultados de alunos portugueses imigrantes com idades compreendidas entre os 8 e os 30 anos de idade, decorrentes da aplicação da bateria de testes de descodificação fonética (provas de identificação de pares mínimos, segmentação, reconstrução fonémica, identificação sintática, audição dicótica). A discussão foca especificamente o desempenho de sujeitos aprendentes de Português Língua Segunda relativamente aos testes de segmentação de palavras (soletração) e de identificação de pares mínimos. Este modelo de engenharia didática, na área específica da didática das línguas segundas, assume-se com uma medida importante para monitorizar a evolução e o estado da proficiência e competência geral linguística dos alunos ao longo do ano letivo, a ser conduzido pelos professores.
- Emotional body odors as context: Effects on cardiac and subjective responsesPublication . Ferreira, Jacqueline; Parma, Valentina; Alho, Laura; Silva, Carlos Fernandes da; Soares, Sandra Cristina de OliveiraMany studies have indicated that the chemical cues from body odors (BOs) of donors experiencing negative emotions can influence the psychophysiological and behavioral response of the observers. However, these olfactory cues have been used mainly as contextual information for processing visual stimuli. Here, for the first time, we evaluate how emotional BO affects the emotional tone of a subsequent BO message. Axillary sweat samples were taken from 20 donors in 3 separate sessions while they watched fear, disgust, or neutral videos. In a double-blind experiment, we assessed the cardiac and subjective responses from 69 participants who were either exposed to negative emotional or neutral BOs. Our results showed a reduced cardiac parasympathetic activity (HF%)-indicating increased stress-when participants smelled the emotional BOs before the neutral BOs, compared to when they smelled neutral followed by emotional BOs. The intensity of the neutral odor also increased following the exposure to both negative BOs. These findings indicate that BOs contain an emotion-dependent chemical cue that affects the perceiver both at the physiological and subjective levels.
- Ethnic influences on the perceptual properties of human chemosignalsPublication . Parma, Valentina; Redolfi, Nelly; Alho, Laura; Rocha, Marta; Ferreira, Jacqueline; Silva, Carlos Fernandes da; Soares, Sandra C.Individuals of African and Caucasian descent show different chemical signatures in their body odors (BO). Does such biological difference have a perceptual correlate? We tested BO donors and raters of Afro-Portuguese (AP) and Caucasian (C) descent to investigate whether olfactory ratings reveal an ethnic bias and whether olfactory ethnic discrimination is possible. C (vs. AP) women rated the C BO as more pleasant, even when controlling for intensity. The C BO labelled as AP was rated as more intense by C raters. Although discriminability of ethnicity and sex is at chance, a nominal advantage for AP vs. C BO emerges.
- Event-related potentials modulated by the perception of sexual dimorphism: The influence of attractiveness and sex of facesPublication . Carrito, Mariana L.; Bem-Haja, Pedro; Silva, Carlos Fernandes da; Perrett, D. I.; Santos, I. M.Sexual dimorphism has been proposed as one of the facial traits to have evolved through sexual selection and to affect attractiveness perception. Even with numerous studies documenting its effect on attractiveness and mate choice, the neurophysiological correlates of the perception of sexual dimorphism are not yet fully understood. In the present study, event-related potentials (ERPs) were recorded during visualisation of faces that had been previously transformed in shape to appear more masculine or more feminine. The participants' task consisted of judging the attractiveness of half of the total number of faces, and performing a sex discrimination task on the other half. Both early and late potentials were modulated by the sex of faces, whereas the effect of the sexually dimorphic transform was mainly visible in the P2 (positive deflection around 200 ms after stimulus onset), EPN (early posterior negativity) and LPP (late positive potential) components. There was an effect of sexual dimorphism on P2 and EPN amplitudes when female participants visualised male faces, which may indicate that masculinity is particularly attended to when viewing opposite sex members. Also, ERP results seem to support the idea of sex differences in social categorisation decisions regarding faces, although differences were not evident on behavioural results. In general, these findings contribute to a better understanding of how humans perceive sexually dimorphic characteristics in other individuals' faces and how they affect attractiveness judgements.
- How teachers' perceptions affect the academic and language assessment of immigrant childrenPublication . Figueiredo, Sandra; Martins, Margarida Alves; Silva, Carlos Fernandes da; Simões, CristinaRecent research evidences inconsistencies in teachers' practice regarding skills assessment of L2 students. Scientific evidence supports that less experienced teachers have lower orientation toward multiple task-tests for non-native students. Research questions: Whether school teachers as having different teaching training and unequal teaching experience with non-native students perceive differently a four-skills scale. Purpose of the study: This study intends to analyse the importance degree between the four skills/tasks: reading, writing, speaking and listening, in the perspective of school teachers. Method: 77 teachers, aged 32-62, with (and without) experience in teaching and adapting materials for immigrant students, divided into six groups according to their scientific domain. Assessment tools included a scale for judgement of four academic tasks adapted from the original “Inventory of Undergraduate and Graduate Level: Reading, Writing, Speaking and Listening Tasks (Rosenfeld, Leung & Ottman, 2001). Main Findings: 1) different degrees of importance attributed by teachers on tasks that should be included in academic and language test for immigrant students; 2) perceptions of teachers are determined by predictors in this order: scientific domain, experience with multicultural classes and lower prediction from teaching service and age; 3) different results between american and portuguese samples answering the same questionnaire.
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