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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

El aprendizaje distribuido como estrategia didáctica en la enseñanza del vocabulario de ELE : Un acercamiento a su uso en el salón escolar sueco / Distributed learning in vocabulary teaching of Spanish in a Swedish school

Gryzelius, Thomas January 2016 (has links)
Aprender nuevas palabras en un idioma extranjero, es decir, el léxico necesario que fundamenta la posibilidad del desarrollo de las destrezas comunicativas, constituye uno de los problemas más complejos en el proceso tanto de enseñanza como de aprendizaje del español como lengua extranjera. En relación con el aprendizaje del vocabulario identificamos un posible problema; el riesgo de que el número de palabras aprendidas se olvide aumenta después de la prueba o los ejercicios. Si nuestros alumnos no pueden ampliar su vocabulario su competencia comunicativa tampoco va a desarrollar.Para poder entender por qué ocurre el problema y cómo se podría encontrar otros recursos didácticos que contribuyan a un cambio en el proceso, investigamos un fenómeno conocido por la psicología de la educación como el efecto de la memoria espaciada - un fenómeno cognitivo que se benéfica de las repeticiones, pero siempre distribuidas en el tiempo. Estrategias de enseñanza que utilizan dicho efecto se refiere como aprendizaje distribuido.Mediante un pequeño estudio analizamos el efecto de la memoria espaciada (ME) como método alternativa. De este estudio podemos inferir que existe un efecto de memoria espaciada tangible en el aprendizaje de los alumnos que estudiaron según un modelo distribuido, es decir con repeticiones.Pudimos constatar un resultado positivo en este pequeño estudio piloto. Los alumnos lograron recordar en la examinación el 85% de las palabras ejercitadas en la clase un mes después. Este resultado abre nuevas perspectivas de estudio e indica que puede haber alternativas didácticas en la enseñanza del vocabulario de ELE en el salón escolar sueco. / Studying and learning words in a foreign language in order to develop a vocabulary that promotes communicative competence, is a daunting task both for students and teachers of Spanish as a foreign language in Sweden and elsewhere. In this context we identify one problem; the possibility that words learned in class will be forgotten as soon as they have been tested on a quiz or exam. If our students cannot incorporate new words into their vocabulary it is quite possible that their communicative development will stop or slow down.       In order to understand this problem and find alternative ways to teach vocabulary we investigated a phenomena called ‘the spaced memory effect’. In the field of educational psychology this is when the learner study with repetitions distributed over time. Practices that build on the spaced memory effect are often called distributed learning.       In a small study we tested this effect as an alternative way of teaching and learning vocabulary. From this study we could conclude that the effect is possible to measure and that it is consistent in all the test subjects that followed a study model that was based on repetitions or a distributed learning model. It was shown that after one month the students were able to remember 85% of the words.       The results from this small study provides new perspectives for further investigation and suggests that there are alternative ways of teaching Spanish vocabulary in Swedish schools.
92

Asymétries en perception et traitement de bas niveau : traces auditives, mémoire a court terme et représentations mentales / Asymmetries in perception and low-level processing : auditory traces, short-term memory and mental representations

Karypidis, Charalampos 15 January 2010 (has links)
L’effet d’ordre de la présentation des stimuli a un impact sur leur discriminabilité. Dans cette thèse, nous étudions le phénomène d’asymétrie et comment celui-ci réagit avec divers facteurs cognitifs localisés dans différentes étapes du traitement. Nous nous focalisons sur le rôle de la périphéricité acoustique, de la dégradation auditive et des représentations mentales permanentes. Des données sur la perception visuelle complètent la partie principale de notre travail. Nous envisageons aussi la variabilité inter- et intra-sujet dans la perception et et dans la production des voyelles. Nos données révèlent que les effets d’ordre sont un mécanisme complexe qui ne peut pas être réduit à un seul facteur déclencheur. / It has been knonw for 150 years that the order of presentation of stimuli has an impact on their discriminability. In this thesis, we have examined the phenomenon of asymmetries in vowel perception ad how it interacts with various cognitive factors located at different steps of the stimulus decoding. We have focused on the role of acoustic peripherality, of auditory decay and of permanent mental representations. Data from visual perception complements the main body of our work. Inter-subject variability in vowel perception and production is also deal with. Our data shows that order effects are a complex mechanism which cannot be reduced to a single trigger factor.
93

Le sentiment de marché : mesure et interêt pour la gestion d'actifs / Market sentiment : measure and importance for asset management

Frugier, Alain 30 September 2011 (has links)
La rationalité parfaite des investisseurs, base de l'hypothèse d'efficience desmarchés, est de plus en plus discutée. Ceci a conduit au développement de la financecomportementale. Le sentiment de marché, qui en est issu, est l'objet de cette étude.Après l'avoir mis en relation avec la rationalité et défini, ses modes de mesure courantset une évaluation de leur capacité à anticiper les rentabilités sont présentés. Ensuite, autravers de deux recherches largement indépendantes, nous (1) montrons de manièreempirique, essentiellement à partir de modèles multi-Agents et d'une modélisation del'impact des chocs d'information sur la distribution des rentabilités, que les skewness etkurtosis de la distribution des rentabilités peuvent être utilisés comme indicateurs dusentiment de marché ; (2) mettons en évidence la présence de mémoire sur de nombreuxindicateurs de sentiment, ce qui invalide les modalités habituelles de leur utilisation,dans le cadre de stratégies contrarian. / The perfect rationality of investors, one of the foundations of theefficient market hypothesis, is increasingly being questioned. This has led to thedevelopment of behavioral finance. Market sentiment, which stems from it, is the focusof this study. Having first linked this concept to rationality and defined it, this studygoes on to present the most common ways of measuring market sentiment and assesstheir ability to anticipate market returns. Then, using two different studies, we do twothings (1) using mainly multi-Agent models and by modeling the impact of informationshocks on the distribution of returns, we empirically show how skewness and kurtosis inthe distribution of returns can be used as market sentiment indicators; (2) wedemonstrate that many standard sentiment indicators are processes affected by long- orshort-Term memory, making them invalid as contrarian indicators even though this ishow they are typically used.
94

Exploring the modulation of information processing by task context

Heisterberg, Lisa M. January 2021 (has links)
No description available.
95

An Iconic-morphological Approach via Commonly-used Roots to English Vocabulary Teaching: How to Help Chinese Senior High School Students Memorize English Vocabulary / none

許國鋒, Hsu , Kuo-feng Unknown Date (has links)
本研究旨在探討「以常用詞根輔以圖像構詞式詞彙教學法」、「常用詞根無圖像構詞式詞彙教學法」及傳統的「詞義說明式詞彙教學法」在學生的詞彙記憶上的差異;本研究亦探討學生的英文詞彙量、構詞察覺度、短期記憶、長期記憶及拼詞能力之間的相關。 本研究的主要發現如下:接受「以常用詞根輔以圖像構詞式詞彙教學法」的學生比接受「常用詞根無圖像構詞式詞彙教學法」及傳統的「詞義說明式詞彙教學法」的學生表現出更好的構詞察覺度、短期記憶、長期記憶及拼詞能力。在這三組中,構詞察覺度較高的學生對生詞有較佳的短期記憶與長期記憶能力,反之亦然;在詞彙記憶方面,短期記憶力較佳則長期記憶力也是較佳,反之亦然;並且,一星期後的後測分數比較高的學生在一個月後的後後測分數也會比較高;再者,詞彙的短期記憶與學生英文詞彙量的差異無關,因為學生所記住的生詞都可以持續短暫的時間,但不一定能長久記憶。 / This study aims to investigate the discrepancy in the use of the iconic-morphological approach via commonly-used roots, the non-iconic morphological approach via commonly-used roots, and the traditional definition-based teaching method in vocabulary memorization. It also explores the correlation between English vocabulary size, awareness of morphology, short-term memory for words, long-term memory for words, and vocabulary spelling abilities. The subjects of this study are 91 third-year students studying at the National Overseas Chinese Experimental Senior High School in Taipei County. They received instruction in the iconic-morphological approach via commonly-used roots, the non-iconic morphological approach via commonly-used roots, and the traditional definition-based teaching method, respectively. In the beginning, the three groups took the same pre-test to examine their vocabulary size. Then, subjects were immediately asked to take post-test 1 to examine their awareness of morphology after receiving different instructions. Later, subjects were asked to memorize forty unknown words within twenty minutes and then to take post-test 2 to investigate their short-term memory for words. A week later, post-test 3 was held to check their long-term memory for words. A month later, they sat for post-test 4, used to explore their longer-term memory for the forty words. In conclusion, the study summarizes the main findings pertinent to the proposed research questions. The students who receive instruction in the iconic-morphological approach via commonly-used roots finally develop higher awareness of morphology, better short-term memory for words, better long-term memory for words, and better spelling ability than those who learn in the traditional definition-based approach or in the non-iconic morphological approach via commonly-used roots. Among the three groups, the students who display higher awareness of morphology have better short-term memory and long-term memory for words, and vice versa. Moreover, those who have better short-term memory have better long-term memory, and vice versa; those who have better one-week long-term memory for words definitely have better one-month long-term memory for words. Interestingly, students can learn words by rote for a short period of time regardless of their vocabulary size. That is, one person’s short-term memory for words is not correlated with his vocabulary size.
96

Die invloed van ekspressiewe skryfoefeninge op die werkende geheue van adolescente en jong volwassenes (The influence of expressive writing on the memory of adolescents and young adults

Swart, Johanna Catherina 12 1900 (has links)
Text in English / Abstracts in Afrikaans and English / Ekspressiewe skryfwerk (ES) – as ‘n metode van intervensie gemik op fisiese en geesteswelstand van deelnemers – word reeds vir ongeveer drie dekades ondersoek. Klein en Boals beweer met hul 2001-studie dat ES ook ‘n positiewe invloed uitoefen op die werkende geheue van individue. Met die huidige studie word die vraag of hierdie bevinding ook van toepassing is op adolessente en jong volwassenes van Suidelike Afrika ondersoek. Dié projek betrek aanvanklik skoolleerders (N = 44) en eerstejaar universiteitstudente (N = 83) in die Suid-Kaap en met die skryfoefeninge word ‘n komponent bygevoeg by een van die eksperimentele groepe waar kognitiewe insette saam met die emosionele onthulling verlang word. Die studie-resultate toon heelwat teenstrydighede, dog die positiewe invloed van ES op die werkspan word by ‘n goeie aantal eksperimentele groep deelnemers waargeneem. Vorige navorsing dui op ‘n verlaging in die voorkoms van indringer- en vermydingsgedagtes na ES tesame met verbeterde werkspan en hierdie verband word van nader beskou deur die huidige studie. Die moontlikheid dat woordtelling per minuut as informele meting van werkspan aanvaar kan word, sowel as die moontlike verband tussen gemoedsvlak en skryfkondisie word ook met die projek ondersoek. / During the past three decades expressive writing has been in the research spotlight as an effective method of intervention in the improvement of human well-being. In 2001 a study done by Klein and Boals claimed that expressive writing also has a positive influence on the working memory of the student participants. The current study investigates the influence of expressive writing on adolescents and young adults in the Southern Africa context. Solution-focused exercises, together with emotional expression during the writing sessions, add a cognitive component to the intervention which strive to create greater impact on working memory capacity (WMC). Previous research indicate that improvement in WMC goes hand in hand with the reduction in the prevalence of intrusive and avoidant thoughts. During the current project the relationship between working memory and these thoughts is investigated. Additionally the possibility of word count as informal measure for WMC are looked at as well as a possible association between mood level and writing condition. / Psychology / M.A. (Psychology)
97

Dinâmica do sistema córtico-hipocampal durante o condicionamento contextual de medo / Cortico-hippocampal system dynamics during contextual fear conditioning

Kunicki, Ana Carolina Bione 03 February 2012 (has links)
O estabelecimento das memórias de longo prazo requer uma efetiva comunicação do hipocampo com o neocortex. Um mecanismo plausível envolvido na comunicação neuronal e na plasticidade sináptica é a sincronização da atividade elétrica cerebral na frequência teta. Estudos recentes mostraram que a sincronização entre os ritmos teta do hipocampo e do córtex pré-frontal aumenta durante a evocação das memórias aversivas e diminui após a extinção do aprendizado. Entretanto, outros ritmos cerebrais, como as ondas delta, também estão envolvidos nas respostas comportamentais do medo e nos processos de memória. Desta forma, o ritmo teta, que já foi bastante estudado pelo seu papel no aprendizado e na memória, e o ritmo delta, por seu envolvimento no ciclo sono-vigília, foram investigados considerando a relação causal entre eles. Ainda não está bem estabelecido como os ritmos delta e teta podem juntos contribuir nos processos cognitivos ou como os ritmos do hipocampo podem influenciar ou receber influencias da atividade cortical. Neste trabalho foi investigada a contribuição dos ritmos delta e teta em função do estado comportamental (vigília ativa ou congelamento) e do tipo de memória evocada (recente ou remota). Além disso, foi realizada uma análise de sincronia de fase para inferir a dinâmica da atividade elétrica entre o córtex pré-frontal medial, o hipocampo e o córtex visual durante a evocação das memórias de medo. Para tanto, os animais foram treinados e testados numa tarefa de condicionamento de medo ao contexto. Neste tipo de condicionamento, o animal aprende a estabelecer uma associação entre um determinado contexto (caixa de condicionamento) e um evento aversivo (choque elétrico nas patas) que ocorreu neste contexto. Quando o animal foi reintroduzido na caixa de condicionamento, o mesmo exibiu uma série de respostas condicionadas incluindo a reação de congelamento. Os resultados mostraram que os ritmos delta e teta estão relacionados de forma específica às respostas comportamentais de medo e de evocação das memórias recente e remota. Observou-se no espectro de potências uma maior contribuição do ritmo teta durante a vigília exploratória, diminuindo durante o congelamento. Neste último, os ratos apresentaram um robusto aumento da contribuição do ritmo delta. Além disso, a medida de causalidade mostrou ser dependente do estado comportamental do animal. Finalmente, um aumento da sincronia entre o hipocampo e o córtex pré-frontal foi evidenciado durante a evocação de memória recente, contraposta à diminuição durante a evocação da memória remota. Estes resultados indicam que a sincronização da atividade elétrica cerebral pode refletir uma facilitação na comunicação neuronal / The establishment of long-term memories requires effective communication of the hippocampus to the neocortex. Electrophysiological activities between hippocampus and prefrontal cortex have shown higher theta synchronization during retrieval of aversive memories and lower during extinction learning. While theta activity is more differently related to learning and memory, delta waves have been more discussed in the context of sleep or \"offline\" states. Few studies have investigated delta waves during \"on-line\" states (such as task-relevant situations) and the contribution of these rhythms to memory storage remains unclear. We recorded electrophysiological data to study the contributions of delta and theta waves in cortico-hippocampal system of rats underwent to contextual fear conditioning. Our experiment consisted of environmental pre-exposition, training with electrical footshocks, and recent/remote memory tests. Two groups of rats were tested one or eighteen days post training for recent or remote memory, respectively. Local field potential time series of two behavioral states were sampled: active exploration and freezing. The results showed that theta and delta rhythms play an important role in behavioral responses and memory processing. They are related to fear recall and their contribution depend on the recent or remote memory. Additionally, using an order parameter we show that theta contribution is strongly pronounced in active exploration, decreasing during freezing. In the latter, the rats presented pronounced delta waves in freezing. Moreover, a behavioral-dependent causality measure showed an increase of theta influence in delta rhythms, resulting in a theta slowing in aversive memory retrieval. Finally, we show an increased synchrony between hippocampus and prefrontal cortex during recall of recent memory, but a decreased synchrony in remote memory. We proposed that synchronized activity may facilitate the communication of information and once the memories are established in the neocortex, the synchronization decreases, and recalling them becomes more independent of the hippocampus. We proposed that delta-theta oscillations of the hippocampus over neocortical areas reflect information processing during aversive memory retrieval
98

Évaluation des effets neuro-inflammatoires de l’exposition périnatale aux anguilles (Anguilla anguilla L.) contaminées naturellement aux polluants organiques persistants sur le comportement et les fonctions cognitives dans un modèle murin / Evaluation of neuroinflammatory effects of perinatal exposure to contaminated eels (Anguilla anguilla L.) by persistent organic pollutants on behavior and cognitive functions using a mouse model

Soualeh, Nidhal 14 December 2017 (has links)
Dans ce travail de thèse, nous avons évalué les effets inflammatoires, comportementaux et cognitifs de l’exposition périnatale des souris à trois matrices alimentaires d’anguilles, reflétant 3 niveaux de pollution (faible, moyenne et haute), tout en considérant le sexe de la progéniture ainsi que les différentes phases d’âges. Les réponses inflammatoires ont été évaluées, aussi bien au niveau cérébral, y compris dans les cellules de la microglie, qu’au niveau périphérique, à 4 stades de vie distincts, et ce dès la naissance jusqu’à l’âge moyen. Chez les souriceaux, mâles et femelles, dont leurs génitrices ont consommé de l’anguille contaminée, durant la période gestationnelle et lactationnelle, vs les témoins dont leurs mères ont consommé uniquement la diète standard, nos résultats ont montré une neuro-inflammation précoce et prononcée, ainsi qu’une production accrue des marqueurs pro-inflammatoires par les cellules de la microglie durant la période néonatale et postnatale. Cette réponse pro-inflammatoire a été chronique puisqu’elle a été à nouveau détectée même à un âge avancé (âges adulte et moyen). Nos résultats mettraient en évidence l’activation et la polarisation des cellules de la microglie depuis la naissance, chez les animaux exposés, vers le phénotype M1, susceptible d’induire les effets neurotoxiques apparus beaucoup plus tard dans les stades de la vie. En effet, un comportement dépressif-like a été observé à l’âge adulte uniquement chez les mâles. Cette altération sexe dépendante du comportement de résignation a été attribuée à l’hyperactivation de l’axe de stress, l’axe hypothalamique pituitaire surrénalien, mise en évidence par une forte production de la corticostérone chez les mâles à l’âge adulte. Chez les femelles, nous avons mis en évidence le développement d’un comportement hyperactif dès l’âge adulte, et d’un déclin cognitif à l’âge moyen. Nos résultats suggèrent que le déficit de la mémoire de rétention des femelles d’âge moyen exposées périnatalement à des anguilles moyennement et hautement contaminées serait lié à la diminution significative de l’activation à la fois d’ERK ½ et du NF-κB ainsi qu’à la réduction significative du taux d’acétylcholine, détectées au niveau de l’hippocampe de ces souris. A partir de ces données et de celles obtenues par d’autres membres de notre équipe, il apparait de plus en plus pertinent de prendre en considération le risque du couplage des effets neuro-oxydatif et neuro-inflammatoire dans la genèse de nombreux troubles cognitifs et comportementaux surtout de manière tardive et irréversible. Cela pourrait également être à l’origine d’une fragilité et d’une imprégnation précoce de différentes populations cellulaires qui conduiraient tardivement à une dégénérescence précoce des cellules en particulier au niveau neuronal et glial. En conclusion, nos résultats suggèrent une programmation périnatale sexe-dépendante des troubles, mis en évidence aussi bien sur le plan comportemental que sur le plan cognitif chez les souris dont leurs mères ont consommé de l’anguille polluée, via des mécanismes inflammatoires. Cela laisse supposer un impact endocrino-dépendant dont il faudrait confirmer la réalité et les mécanismes / Several lines of evidence indicate that early-life inflammation may predispose to mental illness in later-life. In our study, we investigated the impact of perinatal exposure to polluted eels on the brain and microglia inflammation in a lifespan approach as well as on the resignation behavior, the locomotor activity and the cognitive performances in the later life of male and female offspring mice. The effects of maternal standard diet (laboratory food) were compared to the same diet enriched with low, intermediate, or highly polluted eels. Our results showed a chronic brain inflammation in male and female offspring mice compared to controls, as assessed at the birth, up weaning, adulthood and middle-age. Activated microglia produced pro-inflammatory markers across the lifespan of male as well as female exposed offspring. The plasmatic level of myeloperoxidase was found to be significantly higher in both adult and middle-aged males and females vs. control offspring. However, high corticosterone levels were only found in adult male offspring mice perinatally exposed to polluted eels, suggesting a sex-selective dysregulation of the adult hypothalamic- pituitary- adrenal (HPA) axis. Sex selective differences were also found in adulthood, with regard to the offspring resignation behavior. Indeed, depressive-like symptoms were only found in adult male mice perinatally exposed to polluted eels. On the middle- age, sexe selective effects were found with regard to memory and locomotor activity. Indeed, hyperactive phenotype was only detected in females. In addition, impaired long-term memory was only detected in middle-aged females, perinatally exposed to either intermediately or highly polluted eels. This deficit was related to decreases in ERK1/2 and p65 activation, and acetylcholine levels that were only detected in female hippocampus exposed to either intermediately or highly polluted eels. In conclusion, our results indicated that early-life inflammatory insults were the plausible causative factor that programmed the behavior impairments and cognitive deficit in the later-life of offspring, and suggested that sex played an important role in the determination of nature of the appeared alterations
99

Dinâmica do sistema córtico-hipocampal durante o condicionamento contextual de medo / Cortico-hippocampal system dynamics during contextual fear conditioning

Ana Carolina Bione Kunicki 03 February 2012 (has links)
O estabelecimento das memórias de longo prazo requer uma efetiva comunicação do hipocampo com o neocortex. Um mecanismo plausível envolvido na comunicação neuronal e na plasticidade sináptica é a sincronização da atividade elétrica cerebral na frequência teta. Estudos recentes mostraram que a sincronização entre os ritmos teta do hipocampo e do córtex pré-frontal aumenta durante a evocação das memórias aversivas e diminui após a extinção do aprendizado. Entretanto, outros ritmos cerebrais, como as ondas delta, também estão envolvidos nas respostas comportamentais do medo e nos processos de memória. Desta forma, o ritmo teta, que já foi bastante estudado pelo seu papel no aprendizado e na memória, e o ritmo delta, por seu envolvimento no ciclo sono-vigília, foram investigados considerando a relação causal entre eles. Ainda não está bem estabelecido como os ritmos delta e teta podem juntos contribuir nos processos cognitivos ou como os ritmos do hipocampo podem influenciar ou receber influencias da atividade cortical. Neste trabalho foi investigada a contribuição dos ritmos delta e teta em função do estado comportamental (vigília ativa ou congelamento) e do tipo de memória evocada (recente ou remota). Além disso, foi realizada uma análise de sincronia de fase para inferir a dinâmica da atividade elétrica entre o córtex pré-frontal medial, o hipocampo e o córtex visual durante a evocação das memórias de medo. Para tanto, os animais foram treinados e testados numa tarefa de condicionamento de medo ao contexto. Neste tipo de condicionamento, o animal aprende a estabelecer uma associação entre um determinado contexto (caixa de condicionamento) e um evento aversivo (choque elétrico nas patas) que ocorreu neste contexto. Quando o animal foi reintroduzido na caixa de condicionamento, o mesmo exibiu uma série de respostas condicionadas incluindo a reação de congelamento. Os resultados mostraram que os ritmos delta e teta estão relacionados de forma específica às respostas comportamentais de medo e de evocação das memórias recente e remota. Observou-se no espectro de potências uma maior contribuição do ritmo teta durante a vigília exploratória, diminuindo durante o congelamento. Neste último, os ratos apresentaram um robusto aumento da contribuição do ritmo delta. Além disso, a medida de causalidade mostrou ser dependente do estado comportamental do animal. Finalmente, um aumento da sincronia entre o hipocampo e o córtex pré-frontal foi evidenciado durante a evocação de memória recente, contraposta à diminuição durante a evocação da memória remota. Estes resultados indicam que a sincronização da atividade elétrica cerebral pode refletir uma facilitação na comunicação neuronal / The establishment of long-term memories requires effective communication of the hippocampus to the neocortex. Electrophysiological activities between hippocampus and prefrontal cortex have shown higher theta synchronization during retrieval of aversive memories and lower during extinction learning. While theta activity is more differently related to learning and memory, delta waves have been more discussed in the context of sleep or \"offline\" states. Few studies have investigated delta waves during \"on-line\" states (such as task-relevant situations) and the contribution of these rhythms to memory storage remains unclear. We recorded electrophysiological data to study the contributions of delta and theta waves in cortico-hippocampal system of rats underwent to contextual fear conditioning. Our experiment consisted of environmental pre-exposition, training with electrical footshocks, and recent/remote memory tests. Two groups of rats were tested one or eighteen days post training for recent or remote memory, respectively. Local field potential time series of two behavioral states were sampled: active exploration and freezing. The results showed that theta and delta rhythms play an important role in behavioral responses and memory processing. They are related to fear recall and their contribution depend on the recent or remote memory. Additionally, using an order parameter we show that theta contribution is strongly pronounced in active exploration, decreasing during freezing. In the latter, the rats presented pronounced delta waves in freezing. Moreover, a behavioral-dependent causality measure showed an increase of theta influence in delta rhythms, resulting in a theta slowing in aversive memory retrieval. Finally, we show an increased synchrony between hippocampus and prefrontal cortex during recall of recent memory, but a decreased synchrony in remote memory. We proposed that synchronized activity may facilitate the communication of information and once the memories are established in the neocortex, the synchronization decreases, and recalling them becomes more independent of the hippocampus. We proposed that delta-theta oscillations of the hippocampus over neocortical areas reflect information processing during aversive memory retrieval
100

Är worked examples användbara inom biologi-undervisning? / Are worked examples useful within biology education?

Claesson, Olle January 2023 (has links)
För att lyckas lösa problem och använda kunskap behöver en person först ha lärt sig grundläggande kunskap om problemområdet. Sådant lärande kräver att den lärandes arbetsminne inte överbelastas med oändamålsenlig information. Studien undersöker effekten av lärandetekniken worked examples, som visats vara effektiv för att inte överbelasta arbetsminnet inom ämnen som fysik och matematik. Worked examples kommer från cognitive load theory och här undersöks teknikens effekt inom biologiundervisning, med fokus på ämnesområdet ekologi. Högstadieelevers kunskap inom ekologi mättes, varpå de inom undervisning antingen arbetade med worked examples eller instuderingsfrågor. Därefter mättes deras kunskapsnivå återigen, för att på så vis jämföra metodernas effekt på deltagarnas lärande. Elever som lärts med worked examples visade på en större kunskapsutveckling gällande snarlika uppgifter som de övat på, medan kunskapsutveckling för frågor med andra lösningsmetoder gav tvetydigt resultat. Tekniken worked examples har härmed visats sig vara en användbar teknik inom ämnesområdet ekologi inom biologiundervisningen. Den kan med fördel användas under initial-inlärningsfas inom biologiämnet för att hjälpa elever förvärva kunskap.

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