Made available in DSpace on 2015-03-05T19:36:37Z (GMT). No. of bitstreams: 0 Previous issue date: 28 / Nenhuma / O presente trabalho apresenta uma revisão bibliográfica feita na base de dados Web of Science, onde foram encontrados 266 artigos que tratam diretamente sobre estimulação aversiva e cognição. Posteriormente, foram utilizados 53 artigos para esta revisão. Fez-se então uma citação das principais categorias e métodos de trabalho, assim como tópicos que direcionam as pesquisas atuais e principais avanços sobre o tema. Considerando os trabalhos encontrados, embora haja um grande avanço, principalmente, nas últimas duas décadas, sobre o assunto, ainda é um campo que necessita de muito estudo, para avaliar a interferência da estimulação aversiva sobre a cognição. / This work presents a bibliographical review of material from Web of Science database. 266 publications were found that link directly aversive stimulation and cognition. Based on further analysis, 53 studies were used for this review. It was made a citation of the main categories and methods then, as well as topics that address the current researches and main progresses on the theme. Considering the selected papers, although there is considerable progress, mainly, in the last two decades on this topic, it is still a field that needs a lot of study in order to evaluate the interference of cognition by aversive stimulation.

Thesis (Ed.D.)--Boston University / The purpose of this study is to construct an instrument to measure objectively locomotor response to rhythmic auditory stimuli. This purpose will be considered accomplished if the instrument distinguishes between members of the study groups; if, as evidence of its validity the results obtained from measuring groups of untrained, trained amateurs, and professional dancers reflect the obvious difference in the rhythmic skill of these groups.

A preocupação crescente com o desenvolvimento de hábitos saudáveis e uma alimentação adequada vêm promovendo o avanço nas ciências dos alimentos, como também nas relações entre estes e o homem. Nas últimas décadas, a qualidade da análise sensorial tem sido estudada não apenas com base na interação entre o homem e o alimento, mas através da compreensão dos fatores subjetivos e emocionais que influenciam os consumidores. O interesse pelos aspectos emocionais que influenciam essas escolhas amplia os estudos para o terreno das ciências psicológicas, que procuram entender as bases neurocognitivas e analíticas do funcionamento cerebral como motivadores desses processos no homem. O trabalho em neurociência cognitiva tem vislumbrado novos paradigmas, com o desenvolvimento de novas técnicas de observação do cérebro, visando conhecer sua estrutura e função, além de permitir a associação de um comportamento clinico ou experimentalmente observado, não só a um correlato mental presumido, mas também a marcadores específicos da atividade mental observada. Neste sentido, a atividade elétrica cerebral adquirida usando-se o eletroencefalograma (EEG) vem sendo, recentemente, muito usada para monitoramento de eventos cerebrais. Portanto, este trabalho tem como objetivo propor um modelo de análise sensorial que permita avaliar quantitativamente a ação do estímulo gustativo no contexto cognitivo, utilizando o EEG. O experimento foi realizado no laboratório de Física Aplica e Computacional (LAFAC), na Universidade Estadual de São Paulo (USP), Campus Pirassununga, no período de maio/2011 a maio/2012, com 23 voluntários (13 do sexo feminino e 10 do sexo masculino), com idade entre 19 e 24 anos. Foram coletados os sinais de EEG destes voluntários no momento em que experimentavam 27 amostras do sabor doce, sendo nove delas a 0% (água), nove com 0,15% de sacarose (limiar) e nove com 5,0% (concentração máxima). Desta amostragem, foi selecionado um grupo de 7 voluntários (5 do sexo feminino e 2 do sexo masculino) para análise dos dados. Neste estudo constatou-se que quatro voluntários do sexo feminino e um do sexo masculino foram capazes de identificar, através de dados obtidos com o EEG, as diferentes dosagens de sacarose. Os resultados permitem concluir que o modelo de análise sensorial proposta, com a utilização de EEG, para avaliar os estímulos gustativos no contexto cognitivo foi satisfatória e permitiu com a utilização de processamento de sinais digitais e AGR (Análise Adaptativa de Gabor) quantificar com eficiência a percepção dos voluntários as diferentes dosagens apresentadas no experimento. Sugere-se que as diferentes percepções dos voluntários no geral, encontradas no EEG, representam as suas singularidades quanto aos significados atribuídos ao sabor e suas correlações. / The growing concern with the development of healthy habits and a balanced diet allows the progress in Food Science as well as in the relationship between human beings and food. In the last decades the quality of the sensorial analysis has been studied not based only on the interaction between human beings and food but also through the comprehension of subjective and emotional factors that influence customers. The interest in emotional aspects which influence such choices extends the studies to the field of Psychological Science that attempts to understand neurocognitive and analytical bases of brain functioning as motivating elements of those human processes. The work in Cognitive Neuroscience has glimpsed new paradigms due to the development of new techniques about brain observation with the purpose of getting to know its structure and function other than allowing the association of behavior observed experimentally or clinical behavior not considering only a presumed mental correlative but also specific markers of mental activity observed in advance. In that aspect the brain electrical activity acquired through electroencephalogram has been recently used to monitor brain events. Therefore, the aim of this work is to propose a sensorial analysis pattern which allows to evaluate quantitatively the action of taste stimuli within a cognitive context using electroencephalogram. The experiment was carried out in the Laboratory of Applied and Computational Physics (LAFAC) in the University of the State of São Paulo (USP), Pirassununga Campus, from May 2011 to May 2012 with 23 volunteers (13 women and 10 men) aging between 19 and 21 years old. The volunteers\' electroencephalogram signals were collected when they tasted 27 sweet flavored samples, being 9 of them with 0% of sucrose (water), 9 with 0.15% of sucrose (threshold), and 9 with 5% of sucrose (maximum concentration). Seven volunteers were selected from this experiment (5 women and 2 men) whose data was analyzed. In this study was found that four women and one man were able to identify, through the EEG data obtained with the different concentrations of sucrose. The results obtained allowed to conclude that the proposed sensorial analysis pattern using electroencephalogram to evaluate taste stimuli within the cognitive context was satisfactory and allowed, along with the use of digital signals processing and Gabor Adaptive Analysis (AGR), to analyze and to quantify efficiently the volunteers\' perception of different doses presented in the experiment. It is suggested that the different perceptions of volunteers in general, encountered in EEG, representing singularities as to the meanings attributed to taste and their correlations.

The major purpose of this investigation was to study the structure, attributes , and supplemental aspects of equivalence classifying of words and pictures made by sixth graders, freshmen college students and junior and senior college students . A particular point of interest was whether or not increasing or decreasing the size of the groups results in different types of equivalence classifying. Other minor goals were to determine the effects of direction of grouping, type of stimuli, and class level on unique reasons produced and recall of stimuli. The results of the study support the thesis that there is a cognitive developmental progression which supports the works of Piaget, Bruner, Vinacke and others. Children, compared to college levels, use a less efficient grouping structure, lower level simple association and concrete and perceptual grouping attributes, lower quality responses, and more specific reasons for grouping. College levels, compared to six grade, use more representational grouping attributes, have higher quality responses, and have a more general level of specificity. In addition, decreasing grouping structure results in a high level of cognitive performance in all aspects of grouping. There were no main effect differences between the words and pictures. However, there were significant interaction effects involving directions, stimuli, and class levels. There were more stimuli recalled and unique reasons produced by the college students. More pictures than words were recalled by all groups. One implication of the results is that decreasing the size of groupings apparently results in a higher level of cognitive functioning. One reason ventured for this result is that decreasing group size results in more divergent thinking and allows the individual to contemplate more possibilities for his groupings. Increasing group size is related to convergent thinking in which the subject is hindered by a previous set. Another implication is that there is a cognitive development a l progression which results in an increasingly more sophisticated ability to deal with the complex stimuli of the environment. Also, there is some evidence that different grade levels handle pictures differently than they do words. More study is needed to clarify the role of different forms of stimuli in classifying. From this study it is clear that there are no main effect differences between words and pictures. However, there certainly appear to be some interaction effects, and these need further clarification.

The safety signal hypothesis suggests that during the absence of stimuli predicting impending shock, the organism is not fearful. The stimuli which predict the absence of shock are therefore called safety signals. The purpose of the present study was to investigate some critical properties of safety signals. Such stimuli in an avoidance or escape situation, according to the opponent process model, are expected to acquire hedonic value opposite to shock. This study examined differences in conditioning variables between safety signals predicting different intensities of shock, and between safety signals present in procedures using predicted shock, and procedures using unpredicted shock. Additionally, the effects of inescapable unpredicted shock with no safety signals present were examined. The general procedure involved exposing pigeons to aversive Pavlovian conditioning and subsequently autoshaping these birds to stimuli which had predicted safety in the aversive situation. Dependent measures included trials to acquisition of the autoshaped response and subsequent rate of keypecking. In the six experimental groups, pigeons were repeatedly and inescapably shocked at either 30 or 90 volts. Each individual 0.5 sec shock was (a) predicted by a specific stimulus or (b) not predicted. Additionally and explicitly unpaired with the shock, a safety signal was presented. For each voltage level, a control group was repeatedly shocked with no stimuli presented at any time. Control groups were included which (a) received no aversive conditioning, (b) were autoshaped to a stimulus which had previously predicted shock, (c) received the aversive conditioning, and (4) were exposed to various stimuli but received no aversive reinforcement. The principal finding was that preexposure to strong shock resulted in delays in response acquisition during subsequent autoshaping. This suggests that the learned helplessness hypothesis obtains with classically conditioned responding. Additionally, the importance of shock-alone control groups in the study of transfer effects is critical. Due to the lack of statistical power, the study was not definitive regarding the nature of safety signals or appetitive-to-appetitive transfers. Statistically significant differences were only found on acquisition measures, and no such differences were found on performance measures.

Male rats have been found to extinguish a conditioned taste aversion slower than females. It has also been found that female rats that have been "handled" (i.e., exposed to daily brief isolation from siblings and mother) during the preweaning period extinguish a taste aversion faster than nonhandled females. The present study sought to combine and extend these findings by testing handled and nonhandled females and males in a conditioned taste aversion under the methodological conditions used in the sex difference research.

<p>People  have  different  strategies  to  regulate  and  control  their  own emotions.  For  short-term  emotion  regulation  of  visual  stimuli, cognitive reappraisal and attentional deployment are of relevance. The present  study  used  self-ratings  and  eye-tracking  data  to  replicate previous  findings  that  eye  movements  are  effective  in  emotion regulation.  25  participants  (6  males)  watched  positive  and  negative pictures in an attend condition and a decrease emotion condition. They rated  their  emotional  experience  and  their  eye  movements  were followed  with  an  eye-tracker.  Ratings  showed  that  they  perceived pictures as less emotional in the decrease condition as compared to the attend condition both for positive and negative pictures. This decrease in  ratings  of  emotional  response  was  larger  for  positive  than  for negative  pictures.  Eye-tracking  data  showed  no  significant  effect  of emotion  regulation condition. Further  research  is proposed  to  include self-ratings  in  studies  of  physiological  changes  due  to  emotion regulation,  to  differentiate  between  strategies  of  emotion  regulation potentially used by participants.</p>

Di-block copolymer of poly[methacrylic acid-block-2-(diethylamino)ethyl methacrylate] [P(MAA-b-DEA)] with narrow molecular weight distribution was synthesized using the atom transfer radical polymerization (ATRP) technique. The micellization behavior of the P(MAA-b-DEA) copolymer in aqueous solution at room temperature and different pH values were examined by potentiometric and conductivity titration, UV-Visible spectrophotometry, ¹H-NMR, static and dynamic laser light scattering. At low pH (< 4.2), core-shell micelles were formed with MAA core and protonated DEA shell. At moderate pH values, the polymer precipitated from water and formed a cloudy solution, where the polymer chains aggregated into larger particles resembling that of a hard sphere induced by electrostatic interactions. At high pH (> 9.5), core-shell like micelles consisting of hydrophobic DEA core and ionized MAA shell were re-established. / Singapore-MIT Alliance (SMA)

This study describes chick-a-dee calling behavior of Carolina chickadees (Poecile carolinensis) in the presence of “flying” predator models. Previous experimental research with black-capped chickadees (Poecile atricapilla) as well as Mexican chickadees (Poecile sclateri) suggested a relationship between the presence of predator stimuli and the note composition of chick-a-dee calls. Carolina chickadees were presented with two types of stimuli in field settings. These models were painted to resemble either a predatory sharp-shinned hawk (Accipiter striatus) or a blue jay (Cyanocitta cristata). Models consisted of pairs of five varying shapes, making ten models in all. A randomly chosen model was covered with a cloth and attached to a zip-line fastened to a tree about five meters high. During the procedure the cloth was removed and the model was released, causing it to “fly” to the opposite end of the zip line, which was attached at ground level. These trials were audio recorded at 20 field sites in eastern Tennessee from January - March 2010 and January - February 2011. Chickadees produced more C notes in response to hawk models than to blue jay models. Additionally, chickadees produced more A and C notes as well as more total notes during the post-exposure period than during the pre-exposure period for both the hawk and the blue jay conditions. The chickadees’ increased production of C notes in response to the hawk stimuli is consistent with previous research conducted on Mexican chickadees, potentially suggesting that the call structure of Carolina chickadees in threatening predator contexts is more similar to that of Mexican, rather than black-capped chickadees. Finally, chickadees increased production of A notes and C notes to the presence of both model types, providing support for the “Better Safe Than Sorry” strategy.

Polyelectrolyte microcapsules containing stimuli-responsive polymers have potential applications in the fields of sensors or actuators, stimulable microcontainers and controlled drug delivery. Such capsules were prepared, with the focus on pH-sensitivity and carbohydrate-sensing. First, pH-responsive polyelectrolyte capsules were produced by means of electrostatic layer-by-layer assembly of oppositely charged weak polyelectrolytes onto colloidal templates that were subsequently removed. The capsules were composed of poly(allylamine hydrochloride) (PAH) and poly(methacrylic acid) (PMA) or poly(4-vinylpyridine) (P4VP) and PMA and varied considerably in their hydrophobicity and the influence of secondary interactions. These polymers were assembled onto CaCO3 and SiO2 particles with diameters of ~ 5 µm, and a new method for the removal of the silica template under mild conditions was proposed. The pH-dependent stability of PAH/PMA and P4VP/PMA capsules was studied by confocal laser scanning microscopy (CLSM). They were stable over a wide pH-range and exhibited a pronounced swelling at the edges of stability, which was attributed to uncompensated positive or negative charges within the multilayers. The swollen state could be stabilized when the electrostatic repulsion was counteracted by hydrogen-bonding, hydrophobic interactions or polymeric entanglement. This stabilization made it possible to reversibly swell and shrink the capsules by tuning the pH of the solution. The pH-dependent ionization degree of PMA was used to modulate the binding of calcium ions. In addition to the pH-sensitivity, the stability and the swelling degree of these capsules at a given pH could be modified, when the ionic strength of the medium was altered. The reversible swelling was accompanied by reversible permeability changes for low and high molecular weight substances. The permeability for glucose was evaluated by studying the time-dependence of the buckling of the capsule walls in glucose solutions and the reversible permeability modulation was used for the encapsulation of polymeric material. A theoretical model was proposed to explain the pH-dependent size variations that took into account an osmotic expanding force and an elastic restoring force to evaluate the pH-dependent size changes of weak polyelectrolyte capsules. Second, sugar-sensitive multilayers were assembled using the reversible covalent ester formation between the polysaccharide mannan and phenylboronic acid moieties that were grafted onto poly(acrylic acid) (PAA). The resulting multilayer films were sensitive to several carbohydrates, showing the highest sensitivity to fructose. The response to carbohydrates resulted from the competitive binding of small molecular weight sugars and mannan to the boronic acid groups within the film, and was observed as a fast dissolution of the multilayers, when they were brought into contact with the sugar-containing solution above a critical concentration. It was also possible to prepare carbohydrate-sensitive multilayer capsules, and their sugar-dependent stability was investigated by following the release of encapsulated rhodamine-labeled bovine serum albumin (TRITC-BSA). / Die Entwicklung von stimulisensitiven Systemen hat in den vergangenen Jahren großes Interesse hervorgerufen. Diese Systeme verändern ihre Eigenschaften in Abhängigkeit von äußeren Einflüssen und haben potenzielle Anwendungsgebiete im Bereich von Sensoren und der kontrollierten Wirkstofffreisetzung. Beispiele für äußere Einflüsse sind die Temperatur, die Salzkonzentration der Lösung, der pH-Wert oder die Gegenwart bestimmter chemischer Substanzen. Polyelektrolyt-Multischicht-Hohlkugeln stellen viel versprechende stimulisensitive Systeme dar, da sie aus dünnen Membranen mit veränderbaren Eigenschaften aufgebaut sind, und eingekapselte Substanzen definiert freigesetzt werden können. Im Rahmen dieser Arbeit wurden zum einen Polyelektrolytkapseln untersucht, deren Stabilität, Größe und Durchlässigkeit abhängig ist vom pH-Wert und der Salzkonzentration der Lösung. Zum anderen wurden Hohlkugeln entwickelt, deren Stabilität durch die Gegenwart verschiedener Zucker in der umgebenden Lösung beeinflusst wurde. Hierbei war es möglich, eine eingekapselte Substanz in Abhängigkeit der Zuckerkonzentration der Lösung freizusetzen. pH-sensitive Polyelektrolyt-Hohlkugeln wurden mit Hilfe der elektrostatischen Layer-by-Layer Methode aufgebaut. Hierbei wurden abwechselnd schwache Polysäuren und Polybasen auf kolloidalen Partikeln adsorbiert und in einem weiteren Schritt wurde das Templat entfernt. Als Polyelektrolyte fanden Poly(allylaminhydrochlorid) (PAH) und Poly(methacrylsäure) (PMA) bzw. Poly(4-vinylpyridin) (P4VP) und PMA Verwendung. Diese zwei Systeme unterscheiden sich in ihren hydrophoben Eigenschaften und dem Einfluss von Sekundärwechselwirkungen. Die Polymere wurden auf CaCO3 und SiO2 Partikeln mit Durchmessern von ~ 5 µm aufgebracht, und eine neue Methode zum Entfernen des Silica-Templats wurde vorgestellt. Die pH-abhängige Stabilität von PAH/PMA und P4VP/PMA Hohlkugeln wurde mit der konfokalen Fluoreszenzmikroskopie untersucht. Beide Systeme waren über einen breiten pH-Bereich stabil und zeigten an der Grenze der Stabilität ein ausgeprägtes Schwellen, das den unkompensierten positiven oder negativen Ladungen der Mulitschichten zugeordnet werden konnte. Gab es innerhalb der Multischichten stabilisierende Wechselwirkungen, z.B. Wasserstoffbrückenbindungen oder hydrophobe Anziehungskräfte, welche der elektrostatischen Destabilisierung entgegenwirkten, so ließ sich der geschwollene Zustand stabilisieren. Diese Stabilisierung ermöglichte das reversible Schwellen der Hohlkugeln durch Veränderung des pH-Wertes der Lösung. Der pH-abhängige Ionisationsgrad von PMA wurde zur Bindung von Calcium-Ionen verwendet. Die Stabilität und das Schwellen der Hohlkugeln konnten durch Variation der Ionenstärke der Lösung modifiziert werden. Das reversible Schwellen wurde von reversiblen Permeabilitätsänderungen für nieder- und hochmolekulare Substanzen begleitet. Die Permeabilität für Glucose wurde mit Hilfe der Zeitabhängigkeit der Verformung der Kapselmembranen in Glucoselösungen untersucht, und die reversible Veränderung der Permeabilität wurde zur Einkapselung von Polymeren verwendet. Die pH-abhängigen Größenänderungen ließen sich mit einem theoretischen Modell beschreiben, das von einem Kräftegleichgewicht zwischen einer osmotischen expansiven Kraft und einer elastischen kontraktiven Kraft ausging. Als zweites stimulisensitives System wurden zuckersensitive Multischichten untersucht. Diese wurden über reversible kovalente Esterbindungen stabilisiert. Als Polymere für den Schichtaufbau fanden das Polysaccharid Mannan und Polyacrylsäure, die mit Aminophenylboronsäure modifiziert war, Verwendung. Die daraus entstehenden Multischichten waren sensitiv gegenüber verschiedenen Kohlenhydraten, mit der größten Selektivität für Fructose. Diese Affinitäten ergaben sich aus der kompetitiven Bindung zwischen niedermolekularen Zuckern und Mannan an die Boronsäuregruppen. Oberhalb einer kritischen Zuckerkonzentration kam es zur schnellen Auflösung der Multischichten. Darüber hinaus war es möglich zuckersensitive Polymerkapseln herzustellen, deren zuckerabhängige Stabilität durch die Freisetzung von eingekapseltem Rinderserumalbumin verfolgt wurde.