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Conscious or zombies self-perception in Callithrix jacchus & Dinoponera quadricepsPolari, Daniel Silva 04 March 2016 (has links)
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Previous issue date: 2016-03-04 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Consci?ncia como fen?meno biol?gico pode consistir de diferentes estados sensoriais, sentimentos e emo??es. Comportamentos especializado, a??es sofisticadas de comunica??o, meta-cogni??o, intera??o social, orienta??o especial, use de mapas mentais para navega??o e mem?ria espaciais, apontam para tipos diferentes de processamentos consciente em g?neros que n?o o Homo. O presente trabalho busca identificar a auto-percep??o em diferentes esp?cies, com testes do espelho em Callithrix jacchus e com testes de auto-localiza??o em Dinoponera quadriceps. O comportamento de C. jacchus no espelho foi catalogado utilizando dois protocolos diferentes: com marca e sem marca. A capacidade de navega??o de D. quadriceps durante o forrageio, foi calculada considerando tr?s diferentes categorias: (1) acesso livre ao ninho/recurso, (2) acesso direto bloqueado por objeto opaco; e 3) bloqueado por objeto transparente. Nossos resultados apontam para auto-percep??o e mambas as esp?cies, com C. jacchus apresentando comportamentos de verifica??o de conting?ncia, auto-observa??o, al?m de utilizar a imagem refletida para observar o ambiente e reagir a marca. D. quadriceps foram capazes de perceber sua pr?pria localiza??o no ambiente e calcular caminhos curtos at? a col?nia ap?s obter o recurso alimentar, em todos os tr?s tipos de testes. Aqui n?s apresentamos evid?ncia de estados conscientes em outras esp?cies que n?o vertebrados. / Consciousness, as a biological phenomenon, may consists of states of feeling, sensation or awareness. Specialized behaviour, sophisticated actions of communication, metacognition, social interaction, spatial orientation, the use of mental maps for navigation, and spatial memory, all point to conscious processing in genus other than Homo. This work aims to identify self-awareness states in two different species: using mirror self-recognition tests in Callithrix jacchus, and using self-perception tests in Dinoponera quadriceps. Displays of C. jacchus self-recognition using a mirror, were appraised with two protocols: no mark and with mark. D.quadriceps navigational capability displays during foraging trips to food resource, were appraised considering three different tests categories: (1) free access, (2) blocked by opaque object; and 3) blocked by clear object. Our results show self-perception in both studied species. With marmosets displaying contingency check behaviour to the specular image, self-observation, environmental exploration using the mirror as a tool and little, but significant mark reactions. Tocandiras were able to perceive its own location and to calculate short return paths to the colony after obtaining the food resource in all three types of tests. Here we provide further evidence of conscious states for species other than vertebrates.
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Avalia??o da influ?ncia de fatores bi?ticos e abi?ticos sobre a sele??o de sinais visuais de cor em lagartos Gymnophitalmideos de cauda coloridaCarvalho, Gustavo Alexandre Braga de 27 April 2016 (has links)
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Previous issue date: 2016-04-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A colora??o pode exercer as mais variadas fun??es dentre os diversos grupos de animais, e, especialmente em lagartos, essa variabilidade funcional ? relativamente alta, podendo atuar, por exemplo, como sinaliza??o reprodutiva, sinaliza??o social e estrat?gia anti-preda??o. Sendo que, a colora??o adotada pelas esp?cies pode variar dependendo das caracter?sticas f?sicas do meio (e.g. iluminante e background) e de fatores bi?ticos (e.g. sistema visual do observador), fazendo com que diferentes colora??es sejam selecionadas de acordo com o ambiente sensorial em quest?o. O objetivo desse trabalho foi testar a hip?tese do direcionamento sensorial na colora??o da cauda de duas esp?cies de lagartos gymnophitalmideos (Vanzosaura multiscutata e Micrablepharus maximiliani). Para isso foram realizadas coletas pontuais em tr?s diferentes ecossistemas (caatinga, restinga e mata atl?ntica) e em duas diferentes esta??es do ano (esta??o chuvosa e seca). A colora??o dos animais, assim como do substrato circundante e do espectro de ilumina??o solar, foi mensurada atrav?s de um espectrofot?metro e essas informa??es foram inseridas em uma modelagem visual para lagartos e poss?veis predadores. Os resultados mostraram picos de reflet?ncia de luz UV nas superf?cies mensuradas das duas esp?cies, o que pode ser o respons?vel por aumentar o contraste para animais com vis?o UV. Lagartos foi o fen?tipo que apresentou melhores resultados na detec??o da cauda das duas esp?cies. Por outro lado, as demais partes do corpo, supostamente teriam fun??o de camuflagem, devido ao seu baixo contraste com o substrato. Tamb?m encontramos uma varia??o do contraste de cor entre animal e substrato para diferentes fen?tipos visuais, encontrados em diferentes observadores. Sendo assim, conclui-se que a comunica??o intra-especifica pode ser o principal fator a influenciar a colora??o consp?cua da cauda das duas esp?cies. Al?m disso, a colora??o azul e vermelha pode cumprir em determinados momentos fun??es diferentes. Com a cauda vermelha, cumprindo fun??o de camuflagem para lagartos, por exemplo. / The coloration can peform a variety of functions among the various groups of animals, and, especially in lizards, this functional variability is relatively high, may act for exemplo as reproduction signaling, social signal and anti-predations strategy. Thus, the color adopted by the species may vary depending on the characteristics of the environment (e.g. Illuminant and background) and biotic factors (e.g. visual system of the observer), so that different colors are selected in according to the sensory environment in question. The aim of this study was to test the hypothesis of sensory drive in the tail coloration of two species of lizards gymnophitalmideos (Vanzosaura multiscutata and Micrablepharus maximiliani). For this were conducted collects samples in three different ecosystems (Caatinga, Sandbank and Atlantic Rain Forest) and in two different seasons (rainy and dry season). The color of the animals, as well as the surrounding substrate and the solar light spectrum was measured by a spectrophotometer and these information were inserted in a visual modeling for lizards and potential predators. The results showed peaks of the UV light in the surfaces of the two species measured, which may be responsible to increase contrast to animals with UV vision. The phenotype of lizard was the one that showed best results in detection of the tail of these two species. On the other hand, the other parts of the body, would supposedly have camouflage function, because of their low contrast with the substrate. We also found a variation of the color contrast between the animal and substrate for different visual phenotypes found in different observers. Therefore, it is concluded that the intraspecific communication may be the main factor affecting the conspicuous coloration of the tail of the two species. Moreover, the blue and red color may exert different functions at certain times. With the red tail fulfilling camouflage function to lizards, for example.
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Variabilidade ac?stica nos botos-cinza (Sotalia guianensis, Van Ben?d?n, 1864)Lopes, Nara Pavan 08 April 2016 (has links)
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Previous issue date: 2016-04-08 / Na comunica??o o sinal ? transmitido por um emissor e pode carregar informa??es a respeito de sua identidade, seu tamanho, seu status sexual, suas habilidades para luta e sobreviv?ncia. M?ltiplos fatores podem interferir nessa comunica??o, alterando o sinal emitido em consequ?ncia de varia??o no ambiente, na morfologia corporal, na aprendizagem social e na transmiss?o cultural. Sinais ac?sticos podem variar entre popula??es. O dialeto ? a varia??o nos sinais de duas popula??es que trocam genes e varia??o micro ou macrogeogr?fica, dependendo da dist?ncia, existe entre popula??es onde n?o h? interc?mbio de indiv?duos. Estes termos n?o est?o bem estabelecidos na comunidade cient?fica e muitas vezes s?o considerados sin?nimos ou s?o usados incorretamente, por isso foi feita uma revis?o para explicar os termos envolvidos na varia??o ac?stica. Uma padroniza??o dos termos foi proposta esclarecendo os processos que podem ou n?o estarem relacionados com a evolu??o desta tipo de varia??o. A varia??o ac?stica est? presente em sinais de odontocetos (golfinhos e outros cet?ceos com dentes, Ordem Cetartiodactyla), que usam esta modalidade de comunica??o na media??o de intera??es sociais, para obten??o de alimento e para orienta??o espacial. Um dos principais sons emitidos pelos golfinhos em suas intera??es ? o assobio (som tonal de frequ?ncia modulada). O objetivo desse estudo foi comparar os assobios dos botos-cinza (Sotalia guianensis) coletados em Ba?a Formosa, RN (6o 22' S; 35o 00' W) com dados publicados das demais localizades na Am?rica Latina. Os resultados mostram correla??es significativas entre frequ?ncia m?xima e final e entre inicial e m?nima, tanto em Ba?a Formosa, quanto nos outros locais, indicando uma preponder?ncia de assobios com modula??o de frequ?ncia ascendente para a esp?cie em toda sua distribui??o. A dura??o teve uma correla??o negativa significativa com a frequ?ncia inicial em todos os locais comparados (p < 0,00001 e r2 = 0,71) e pode indicar que existe um limiar fisiol?gico para produ??o de assobios muito agudos. A an?lise de componentes principais dividiu os locais em dois grupos maiores, por?m n?o foi devido a uma varia??o latitudinal. Provavelmente diferen?as no m?todo de amostragem (equipamentos com taxas de frequ?ncia limite distintas e par?metros de an?lise espectral distintos), varia??es no ambiente, diferen?as nas frequ?ncias de filhotes (produz sons mais agudos) ou animais de maior porte (emite frequ?ncias menores) e aprendizagem vocal social podem estar mascarando efeitos geogr?ficos nos padr?es vocais. / In communication a signal is transmitted by a sender and can carry information about its identity, size, sexual status, ability to fight and to survive. Multiple factors can interfere with this communication, varying the output signal as a result of variation in the environment, body size, social learning and cultural transmission. Acoustic signals may vary within species between populations. Dialects are signal variations of two populations that can exchange genes and geographic variation micro- or macro-geographic, depending on the distance, occurs when individuals from different populations don?t mix. These terms are not well established in the literature and are often considered the same or used errouneously, thus a revision was made to clarify the terms involved in acoustic variation. A standardization of terms is proposed and clear deffinitions presented based on the processes that may or may not be related to the evolution of variability. Odontocetes (toothed whales, Order Cetartiodactyla) use acoustic communication in the mediation of social interactions, to obtain food and to navigate. One of the main sounds produced by dolphins in their interactions is the whistle (frequency modulated tonal sound). This study aimed to compare whistles of estuarine dolphins (Sotalia guianensis) collected in Ba?a Formosa, RN (6o 22' S; 35? 00' W) with published data from other sites in Latin America. The results show significant correlations between maximum and end frequencies as well as between initial and minimum frequencies in Ba?a Formosa as well as in all other places, indicating a preponderance of frequency ascending whistles used by the species along its distribution. The duration had a significant negative correlation with the initial frequency at all locations tested (p <0.00001 and r = 0.71) and suggests a physiological threshold for high frequency whistles. The principal component analysis divided sites into two major groups, but the discrimination was not related to latitudinal variation. Sampling differences (equipment with distinct sample rates) and analyses with different parameter values likely resulted in different results. Other likely explanations are: variations due to the environment, presence and percentage of calves in the data samples (producing higher frequency sounds) or larger animals (emit lower frequencies) and social vocal learning.
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Toca que o c?rebro tamb?m dan?a: efeito da ritmicidade de tons auditivos sobre par?metros comportamentais e eletrofisiol?gicos da execu??o de uma tarefa de soma aritm?ticaAlencar, Jo?o Carlos Nascimento de 09 May 2017 (has links)
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Previous issue date: 2017-05-09 / Sequ?ncias de est?mulos r?tmicos apresentados na faixa 125-2000ms (0.3-8Hz) podem ter efeitos importantes sobre a percep??o, motricidade e a cogni??o. A "Dynamic Attending" ? uma teoria que pressup?e a exist?ncia de oscila??es atencionais flex?veis ? sincroniza??o com eventos ambientais r?tmicos, fen?meno denominado arrastamento. A percep??o de ritmo tem sido implicada a ?reas classicamente de controle motor, notadamente os n?cleos da base. Estes n?cleos t?m sido atrelados tamb?m ao funcionamento executivo, atrav?s de la?os c?rtico-estriatais-tal?mico-corticais. Considerando as fun??es executivas sediadas no c?rtex pr?-frontal como integrantes desse circuito, o objetivo deste estudo ? caracterizar o efeito de est?mulos auditivos r?tmicos sobre par?metros de comportamento motor, desempenho cognitivo executivo e sinais eletrofisiol?gicos. A amostra (n=24) foi calculada a partir do software G*Power 3.1. Os participantes foram submetidos a tarefas de tempo motor espont?neo e tarefas de processamento executivo (soma sequencial de d?gitos), com ou sem a presen?a de pulsos sonoros isocr?nicos de tr?s diferentes intervalos. Os resultados mostram que h? sincroniza??o do per?odo motor aos pulsos com ISI (Intervalo entre est?mulos, do ingl?s, ?Inter Stimulus Interval?) igual a 500 ms, e que ISI com 350 ms ou 650 ms aumentam a variabilidade das batidas. N?o foi encontrada diferen?a entre as manipula??es experimentais no que concerne ? ativa??o auton?mica, exceto por diminui??o da frequ?ncia card?aca durante a realiza??o da tarefa com som N?o-Sincronizado 350 ms. Com rela??o aos dados eletroencefalogr?ficos, diferentes padr?es de pot?ncia espectral est?o vinculados ao intervalo de estimula??o. O ?ndice de modula??o delta-gama est? negativamente correlacionado ? taxa de acertos na condi??o 350 ms, e positivamente correlacionado na condi??o Sincronizada. O n?mero de acertos est? atrelado ao ISI, mas o Tempo de rea??o parece ter maior modula??o do ISI e do som. Nossos resultados de tempo motor espont?neo sugerem a exist?ncia de uma ?regi?o ?tima de arrastamento?, com centro em 500 ms, no qual h? maior suscetibilidade de sincroniza??o motora involunt?ria. Al?m disso, os dados indicam independ?ncia entre as fun??es executivas ?quentes? e ?frias?, e que o sistema nervoso parece acionar diferentes estrat?gias de processamento para diferentes contextos temporais do ambiente. Isto ? consistente com um modo r?tmico de processamento, que, no entanto, pode implicar em redu??o do desempenho cognitivo mediante de alta exig?ncia por velocidade de processamento. / Sequences of stimuli presented between 125-2000 ms (0.3-8Hz) may impact on perception, motor responses and cognition. Dynamic Attending Theory postulates oscillations of attention, that may synchronize by entrainment to rhythmic events from environment. Rhythm perception has been shown to involve classical motor areas, notably basal ganglia. These sub-cortical nuclei has been also linked to executive functioning, due to existence of cortical-striatum-thalamic-cortical loops. Since executive function is based on prefrontal cortex activity, this work aims to characterize effect of auditory rhythmic stimuli on motor behavior, executive function and electrophysiological responses. Sample (n=24) was previously calculated by G*Power 3.1 software. Participants were submitted to finger tapping and executive tasks (sequential arithmetic sum), while auditory tones were played or not. Our results show motor synchronization for ISI 500 ms, and increased variability for ISI 350 ms and 650 ms. Autonomic electrophysiological responses did not show any changes, except for a decreased heart rate at ISI 350 ms, Non-Synchronized Condition. Delta-Gama Modulation Index is negatively correlated with hitrate for ISI 350 ms, but positively correlated with hitrate at Synchronized Condition. ISI impacts on hitrate, but a larger modulation of both ISI and auditory stimuli over Reaction Time is shown. Our results suggest an ?optimal entrainment range?, centered at 500 ms, and an increased likelihood for involuntary synchronization at this point. Besides, results suggest so-called cold and hot executive functions are independent processes, and also that nervous system may activate different processing ways for different temporal contexts. These findings also corroborate the existence of a rhythmic processing mode, however, with decreased performance through high speed processing request.
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Screening neurocognitivo nella condizione di fragilità. Validazione di strumenti di assessment tra neuropsicologia e neuroinformatics / SCREENING NEUROCOGNITIVO NELLE CONDIZIONI DI FRAGILITA'. VALIDAZIONE DI STRUMENTI DI ASSESSMENT TRA NEUROPSICOLOGIA E NEUROINFORMATICS / Neurocognitive screening in the condition of frailty. Validation of assessment tools between neuropsychology and neuroinformaticsANGELILLO, MARIA TERESA 11 May 2021 (has links)
Questa sintesi conclusiva del percorso di dottorato ruota attorno al costrutto di fragilità, attualmente definita come una condizione disfunzionale dinamica di natura multi-sistemica, associata a un aumentato rischio di conseguenze negative quali istituzionalizzazione, ospedalizzazione e morte.
Come illustrato tramite gli studi inclusi nella presente tesi, le osservazioni empiriche e l’esperienza in ambito clinico hanno sistematicamente evidenziato l’assenza di strumenti di screening cognitivo nella fragilità che presentino sistematicamente valore clinico e validità trasversalmente a diverse tipologie di pazienti o utenti fragili, affetti da disturbi neurologici e cognitivi o che presentino profili di rischio psicosociale.
Nei capitoli empirici sono stati riportati tre studi che hanno riguardato, il primo, la valutazione del potenziale clinico di un nuovo test di screening cognitivo, il CASP, somministrabile anche a persone affette da afasia. Questo è stato comparato con strumenti classici come il MMSE e il MoCA.
Nel secondo studio è stato sviluppato e testato un protocollo di valutazione della fragilità cognitiva e psicosociale nella malattia cronica, ideato per essere inclusivo anche nel suo utilizzo con pazienti migranti.
Infine, il terzo studio, oltre a mirare – come i precedenti – all’arricchimento della cassetta di attrezzi del neurospicologo, si è focalizzato sull’integrazione del testing neuropsicologico classico con le potenzialità della neuroinformatica, avendo come obiettivo lo sviluppo di un approccio di screening multi-componenziale e di un sistema di machine learning per finalità diagnostiche nell’ambito dell’invecchiamento fisiologico e patologico, che non fosse una mera digitalizzazione di test neuropsicologici tradizionali. / This final synthesis of the PhD program revolves around the construct of fragility, currently defined as a dynamic dysfunctional condition of a multi-systemic nature, associated with an increased risk of negative consequences such as institutionalization, hospitalization and death.
As illustrated through the studies included in this thesis, empirical observations and experience in the clinical setting have systematically highlighted the absence of cognitive screening tools in frailty that systematically present clinical value and validity across different types of patients or frail users, suffering from neurological and cognitive disorders or with psychosocial risk profiles.
Three studies have been reported in the empirical chapters which concerned, the first, the evaluation of the clinical potential of a new cognitive screening test, CASP, which can also be administered to people with aphasia. This has been compared with classical instruments such as the MMSE and the MoCA.
In the second study, a protocol for assessing cognitive and psychosocial frailty in chronic disease was developed and tested, designed to be inclusive also in its use with migrant patients.
Finally, the third study, in addition to aiming - like the previous ones - at the enrichment of the neurospychologist's toolbox, focused on the integration of classical neuropsychological testing with the potential of neuroinformatics, aiming at the development of a screening approach. multi-component and a machine learning system for diagnostic purposes in the field of physiological and pathological aging, which was not a mere digitization of traditional neuropsychological tests.
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Children's representation of spatial boundariesGianni, Eugenia January 2018 (has links)
Finding the way home, orienting into familiar and unfamiliar environments, computing our place and position with reference to internal and external cues are essential everyday tasks for animals. It is generally acknowledged that these tasks are accomplished by the brain by means of the internal formation of complex spatial representation, the so called “cognitive maps”. How the brain can form these cognitive maps is a very debated issue in the field of neuroscience. An important stream of research tried to find out what the main environmental features the brain tends to store while navigating are. In order to investigate this, researchers have observed the behavior of animals after being disoriented in a familiar environment. The reorientation paradigm turned out to be a very interesting tool to study spatial cognition because it allows researchers to figure out which environmental components the animals remember and rely on in order to find their way after they have lost track of their heading and position. Experiments with both human adults, children and nonhuman animals have shown that an important feature of the environment the subjects tend to store to reorient is the geometry of the boundaries’ layout (e.g., room shape). Children from as early as 2 years of age have been shown to be able to use the geometric shape of the spatial layout by searching an object hidden in one corner of a rectangular enclosure both in the correct corner and in its geometric equivalent. But which perceptual and physical factors define spatial boundaries? Which geometric components of boundaries are children most sensitive to? How are the same geometric components used in other spatial tasks such as map reading? In our studies we tried to answer these fundamental questions. In our first study we investigated whether children are sensitive to boundaries that constitute either physical or visual obstacles. To this aim we tested children in a reorientation task with both an arena made up of transparent surfaces and an arena made up of opaque surfaces. By using transparent surfaces, we were able to minimize the visually occlusive component of the boundaries but leave intact its physical component. Opaque boundaries presented, instead, both the visual and physical components. In our second study, we further investigated how does the material and visual appearance of boundaries affect navigation by testing children in an arena made up of 20 closely-aligned objects. In this experiment we made the surfaces visually discontinuous, but the configuration of objects was made sufficiently dense to prevent movement and to underline the geometric structure. In our third study, we asked which components of the Euclidean geometry are children most sensitive to while navigating by geometric boundaries and making a map task. In particular we investigated the use of distance and length both in a reorientation task and a map-placement task. The results showed that important developmental changes occur in children’s representation of spatial boundaries and of their geometric components. In particular children became proficient at using transparent surfaces only at the age of five and they start using boundaries made up of closely- aligned objects at the age of seven. At the same time, we showed that the young children (36 to 42 months) reorient correctly in a disorientation task by using the geometric property of distance, rather than length. The same group of children were shown not to be able to use distance nor length in a map task, while they showed the ability to use angle. These results suggest that not all kinds of boundaries are processed equally by children and that their visual aspect might be more important that their property of being obstacles to movement, particularly early in development. They are important because they inform of which material and physical properties of boundaries children are most sensitive to and they can help understanding how to design and build safe environments for children. Moreover, they suggest the geometric property used by young children to reorient is distance, essentially contributing to the wide debate on how children and animals could solve the reorientation task. Finally, they showed that the use of geometric properties in a reorientation task and in a map task might have two different developmental trajectories, suggesting these two competences might be mediated by two different systems and providing an important insight into the development of geometric competences in children.
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Left prefrontal and parietal contribution to sentence processing: a neuromodulation approachVercesi, Lorenzo 04 December 2023 (has links)
Describing a comprehensive neurofunctional model of sentence comprehension has always been a complex challenge. On one hand, disentangling the subprocesses that are necessary for computing the meaning of a sentence and their neural underpinnings is insidious. Each subprocess is closely interconnected with the others, and isolating only one as if it were separable can undermine the investigation of the overall process above. On the other hand, available data on the neural basis of sentence processing are not straightforward. This thesis explores relevant contributions and attempts to highlight open questions regarding the neural basis of two key processes in sentence comprehension, namely morphosyntactic processing and thematic role assignment. It presents and discusses original data resulting from an experiment that, to our knowledge, represents the first investigation of the neural basis of these two processes in the same sentential context. Results demonstrate that morphosyntactic and thematic processing rely on functionally distinct neural correlates in the left hemisphere. Morphosyntactic aspects are mostly processed in a left prefrontal network including the left inferior frontal gyrus (IFG) and the middle frontal gyrus (MFG), whereas thematic role assignment correlates with a left parietal node including the left intraparietal sulcus (IPS). Moreover, it is argued that results support the view that these regions play a language-related rather than domain-general role in human cognition. Finally, two statistical approaches to the analysis of the same TMS language data (ANOVA and Linear Mixed Models – LMMs) are compared. Their outcomes are discussed and an attempt is made at accounting for similarities and differences. Results suggest that the two models should not be considered on a sort of quality hierarchy according to which one has greater or lesser explanatory power than the other. Rather, they both represent legitimate and reliable approaches to account for data variability.
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The recognition of emotional biological movement in individuals with typical development and Autism Spectrum Disorder (ASD)Mazzoni, Noemi January 2017 (has links)
People with Autism Spectrum Disorder (ASD) have difficulties in dealing with social interaction (DSM V, 2013). From long time, it has been reported deficit in recognizing gaze, face and intentions of others. Besides that, in the last decade numerous finds have showed an impairment in coding the human body movements. During my PhD I have explored the ability in recognizing the emotional valence of human movements in people with ASD and with typical development. In order to understand developmental changes, I have initially compared this ability between children and adults. In order to understand the role of intelligence, I have included people with high and low functioning ASD, either in children and adults samples. In the first study, we compared TD children and children with ASD with different level of functioning to investigate i) whether the difficulties in ASD population were associated to emotion comprehension or related to a more basic visual processing of biological motion, and ii) to explore whether this ability improves according to the age and to the non-verbal IQ. To this purposes, we presented point-light (PLDs) and full-light (FLDs) version of human movements with three different emotional valence (Happy, Fearful, Neutral). Our main findings showed that:
-TD children were more accurate in recognizing the emotional content of body movements when the shape of the body was visible (i.e. FLDs), compared to the view of pure motion information (i.e. PLDs), but there were no differences in RT across display conditions. This result suggests that school-aged children are able to correctly identify the emotional valence of dynamic bodily expression, also when the form information is minimized by presenting PLDs.
-According to the emotional content, we found that the valence had an effect on the performance of TD children. In particular, TD children recognized happy bodily expressions with lower accuracy than fearful and neutral movements. Besides, fearful movements were identified more rapidly. We hypothesized that, from an evolutionary point of view, it is more important to recognize fearful signals when they are far from us. Body movements are particularly relevant to convey other people’s state and intentions from a distance, hence bodies are preferential channels to convey fearful signals.
-Comparing typical and atypical children, we found that TD were more accurate and more rapid than children with ASD in recognizing the emotional valence of body movements. Moreover, children with HF ASD outperformed children with LF ASD and their performance was significantly predicted from age and nonverbal IQ. This results suggest that the nonverbal abilities have a role in body movement comprehension, probably underpinning the development of compensatory mechanisms which improve with age.
-Compared to TD children, children with ASD were impaired not only in understanding the emotional expressions, but also in recognizing the neutral actions. Irrespectively to their IQ level, children with ASD did not benefit from the richness of visual information, and their ability to recognize BM did not change according to the emotional valence. This finding suggests that the difficulty encountered by individuals with ASD in social interaction could be more generally related to biological motion elaboration, rather than being specific for the emotions comprehension. Hence, the lack in emotion recognition in ASD seems to be attributable to a deficit in elaborating motion cues rather than emotional information.
To interpret the body movements, children with ASD may adopt compensatory mechanisms, which acquisition seems to be mediated by the nonverbal IQ and improving with age. If this was the case, we should expect an improvement in the ability of recognizing the BM in adults with ASD, with respect to children with ASD, and this improvement should have been correlated with the non-verbal IQ level. To explore this hypothesis, we run a second experiment, were we asked to a group of TD adults, a group of adults with high functioning Autism matched for age and non-verbal IQ, and a group of adults with low functioning Autism matched for age, to performed the same BM recognition task that children did in our first experiment. Results with adults confirmed what we found in children: the emotional valence and the richness of visual information did not modulate the Accuracy and the velocity in recognizing the BM stimuli in ASD, suggesting that the whole body movement is elaborated differently in ASD than in TD adults and that the impairment in ASD is more related to the processing of body movement, rather than being specific for the emotion comprehension.
In a third study, we explored the developmental changes in the ability of recognizing the emotional meaning of human whole-body movements from childhood to adulthood. To this aim, we compared the performance between children and adults in each group of Functioning. Results showed that TD adults were more accurate and faster than TD children; FLDs were recognized with higher accuracy and quicker than PLDs; and fearful and neutral movements were recognized significantly better than happy ones. In participants with ASD, adults were significantly more accurate than children, but not faster. Also, we did not find any difference between displays or emotional categories. This results suggest that the understanding of body movements in individuals with ASD improve with age but the mechanism underpinning this ability works differently.
In a fourth experiment we investigate whether the impairment in understanding social relevant signals in individuals with high functioning autism (HF ASD) was restricted to body movements or widespread to other social cues, such as facial expressions. Also, we investigated the role of movement in perceiving bodily expressions. To this aim, we explored whether there was a difference in recognizing the body expressions represented by dynamic or static stimuli. Finally, we investigated whether the vision of the body form, compared to the sight of pure motion information, could influence the identification of the emotional content of body movements. We did not found any group differences in accuracy, but there was a group difference in RTs specific for dynamic stimuli (TD were significantly faster than ASD in recognizing PLDs, and marginally in FLDs). These results suggest that HF ASD adopt compensatory mechanism to understand the meaning of facial and bodily expression that allow them to correctly recognize the emotional valence conveyed by face and body movements. However, this mechanism has a cost in terms of rapidity. In particular, ASD seems to need more time to identify dynamic body stimuli but not images of body expressions, suggesting a deficit in processing the actual body motion. In particular, the comprehension of happy body movements result difficult and time consuming. Indeed, happiness was better recognized from facial expressions and was harder to be identified when expressed by body movements.
In the fifth experiment we used TMS-adaptation paradigm to explore the existence of a neural system specialized for the elaboration of emotional body movements. We first behaviourally investigated the existence of an adaptation for emotional PLDs. TD adult participant were adapted with point-light video clips depicting fearful, happy or neutral actions and then asked to recognize point-light with same/different emotional content. Results showed an adaptation after-effect only for incongruent stimuli, suggesting the existence of a neural mechanism for perceiving the body emotion specifically. Subsequently, in a TMS experiment we explore the possible brain location of this mechanism. The sites we stimulated are nodes of the neural network responsible for the human motion understanding, and they are reported to be abnormally activated in ASD. We found a reversed after-effect following TMS over aIPS, while the adaptation was still present after stimulation over pSTS and the control site. These results demonstrate that aIPS contains neurons that specifically code for the emotional body expressions, suggesting that the difficulties encountered by individuals with ASD in understanding the emotional signal during social interaction might rely to deficit in this mirror area.
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Directional relationships between BOLD activity and autonomic nervous system fluctuations revealed by fast fMRI acquisitionIacovella, Vittorio January 2012 (has links)
The problem of the relationship between brain function, characterized by functional magnetic resonance imaging, and physiological fluctuations by means of cardiac / respiratory oscillations is one of the most debated topics in the last decade. In recent literature, a great number of studies are found that focus on both practical and conceptual aspects about this topic. In this work, we start with reviewing two distinct approaches in considering physiology - related sequences with respect to functional magnetic resonance imaging: one treating physiology - related fluctuations as generators of noise, the other considering them as carriers of cognitively relevant information. In chapter 2 – “Physiology – related effects in the BOLD signal at rest at 4T”, we consider physiological quantities as generators of noise, and discuss conceptual flaws researchers have to face when dealing with data de-noising procedures. We point out that it can be difficult to show that the procedure has achieved its stated aim, i.e. to remove only physiology - related components from the data. As a practical solution, we present a benchmark for assessing whether correction for physiological noise has achieved its stated aim, based on the principle of permutation testing. In chapter 3 – “Directional relationships between BOLD activity and autonomic nervous system fluctuations revealed by fast fMRI acquisition”, on the other hand, we will consider autonomic indicants derived from physiological time - series as meaningful components of the BOLD signal. There, we describe a FMRI experiment building on this, where the goal was to localize brain areas whose activity is directionally related to autonomic one, in a top - down modulation fashion. In chapter 4 we recap the conclusions we found from the two approaches and we summarize the general contributions of our findings. We point out that bringing together the distinct approaches we reviewed lead us to mainly two contributions. On one hand we thought back the validity of almost established procedures in FMRI resting - state pre-processing pipelines. On the other we were able to say something new about general relationship between BOLD and autonomic activity, resting state fluctuations and deactivation theory.
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The relationships among genes, psychological traits, and social behaviorCataldo, Ilaria 13 February 2020 (has links)
In just over ten years, internet-based technologies revolutionized several aspects of daily human life, including social interactions. Social media sites (SNSs), such as Facebook, Instagram, and Twitter, have dramatically changed the way people keep in touch or make new acquaintances. On the flipside, recent research have highlighted the risk for and inappropriate use of SNSs, which might result in personal discomfort or a mental disorder. For this reason, it is important to understand how these issues develop starting from the diverse contexts and individual features. The main aim of the present Ph.D. project is to identify to which extent the interaction between psychological components, like perceived parental warmth, and genetic susceptibility to the familiar environment can describe the social behavior online and offline. The underlying hypothesis is that sensibility to the familiar context will represent a positive factor, if the person recalls a good perception of parental care, leading to confident psychological mechanisms in adulthood, hence to more optimal neural responses to social stressors in real life, and to the appropriate use of social media. To this aim, three studies have been performed:
•Study 1. Analysis of the impact of perceived early social experience on the formation of interactional patterns in adult social interaction in two different countries (Italy and Singapore);
•Study 2. Investigation on how the interaction between genetic features of oxytocin receptor gene polymorphisms and perceived early social experience affect the neurophysiological responses to cries;
•Study 3. Exploration of the link between adult psychological dimensions related to social behavior and metrics of usage on Instagram platform.
The experimental activities have been performed in two different laboratories: as for the Italian samples, questionnaires and genetic information were collected at the Affiliative Behavior and PhysiologyLaboratory in Rovereto; with regards to the Singaporean sample, participants completed the questionnaires, then were tested for genetics, Near InfraRed Spectroscopy (NIRS), Electrocardiogram (ECG) at the Social and Affective Neuroscience set in Nanyang Technological University. One of the purposes of the overall project was the construction of a rich database, which aims to include information about genetic polymorphisms proved to be sensitive to social environment (oxytocin receptor gene rs53576, rs2254298, and serotonin rs25531), recalled parental warmth, main dimensions of adult attachment, neural and physiological responses to social distress, like listening to cries, and behavior on two main social media platforms, such are Facebook and Instagram. This complex design gives the project several strengths, such as the possibility to focus on the contribution of diverse factors within a bio-psycho-i
social frame, that is claimed to be the more appropriate by scientific community standard, in order to have a wider and deeper understanding of human behavior. Secondly, results generated from studies based on this database would allow filling the present gap about social media usage and psychological mechanisms, providing a further comparison with offline behavior. Lastly, results might be helpful when implemented in clinical work to understand if and how social media can become a useful mean in clinical work. The temporary fragility of this project is related to the genetic sample size, as a broader sampling would be necessary to have a comparable amount of the different variants and generate more reliable explanations. However, this data collection represents a starting point, as it resents of temporal constraints. Future efforts are necessary to enrich the dataset and to find appropriate methodologies to examine in depth the interaction between all the factors
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