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探討金融危機下融資方式對借款人績效表現的影響 / How do financing methods affect borrowers' performance in the financial crisis?朱柏森 Unknown Date (has links)
本篇論文使用2001年到2012年的美國公司作為研究樣本,探討借款公司在金融危機下的表現,是否與借款公司的融資方式有關。實證結果顯示在金融危機下確實僅能透過貸款融資的公司表現會較差,因為在金融危機時,會造成金融體系的信用緊縮,所以導致受金融危機影響的銀行會減少借出量並增加貸款利差。另外,融資彈性較佳的公司似乎表現沒有特別突出,可能隱含在金融危機時也無法在貸款市場上獲得一些好處。 / In this paper, we use U.S. company data from 2001 to 2012 as the research sample to examine the relationship between borrowers’ performance and borrowers’ financing methods in the financial crisis. Empirical results show that the performance of borrowers which can only use loan financing is the worst in the financial crisis. There is credit crunch in the financial system because of the financial crisis, and the banks which are affected by financial crisis will reduce the lending amount and increase loan spreads. In addition, the performance of borrowers with more financing methods did not seem particularly prominent, and we think it implies borrowers with more financing methods could not get benefits from the loan market in financial crisis.
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La finance solidaire : un système de relations de financement. / ‘Solidarity-based finance’ : a system of funding partnershipsArtis, Amélie 23 September 2011 (has links)
La finance solidaire se caractérise par un système de relations de financement entre des agents économiques : une relation de confiance découlant d'espaces de socialisation, une relation d'accompagnement facilitant la construction d'anticipations convergentes, et une relation financière stricto sensu. Elle s'inscrit dans les mutations socioéconomiques institutionnelles qui affectent l'offre et la demande de financement. Elle construit de nouvelles réponses à destination des agents productifs exclus du fait des transformations de la régulation financière, prenant ainsi en charge des espaces de financement périphériques nécessaire à la durabilité du système financier dominant. La finance solidaire est mise en œuvre par des organisations diversifiées partageant des caractéristiques particulières. Elle est l'expression d'une convention de financement solidaire territorialisée qui repose sur des modalités d'acquisition de l'information à la fois personnalisées et normalisées, sur des garanties collectives et sur l'association de différentes parties prenantes (associations, banques coopératives et lucratives, entreprises, collectivités territoriales). La diversité et l'articulation de ressources de nature différente engagent la finance solidaire à ancrer son action dans un compromis entre plusieurs logiques d'actions, aux fondements plus ou moins stables. Du fait de cette nature partenariale, les organisations de finance solidaire évoluent dans un environnement non concurrentiel qui assure néanmoins des moyens de financement pour la re-dynamisation d'une partie des activités économiques de proximité. Elle contribue ainsi à l'adaptation du système financier tout en proposant de diffuser des règles de financement innovantes. / ‘Solidarity-based finance' is characterized by a system of funding partnerships between economical operators : a trust-based relation emerging from social interactions, a stewardship enabling convergent anticipations, and a financial partnership. It operates in socio-economic institutional mutations which affect the supply and demand of funding. It offers new opportunities to productive operators excluded by financial regulation transformations. Therefore, peripheral financial activities required to sustain the dominant financial system are taken into consideration. The ‘solidarity-based finance' is implemented by various organizations sharing specific characteristics. This unique concept is based upon territorialized solidarity-based funding agreements that are defined by information acquiring mechanisms (which are individualized but nonetheless normalized); collective commitments and association of various stakeholders (civil society, cooperative banks, local authorities, corporations). The diversity of resources and their interactions compel ‘solidarity-based finance' to anchor its role in a mediation between several policies, with more or less solid ground rules. Because of this collaborative nature, ‘solidarity-based finance' organizations operate in a non-competitive environment. However, they also offer means of funding for the reinstatement of part of local economy. It so contributes to the mutations of the wider financial system while promoting innovative means of funding.
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Realitní trh v České republice a Velké Británii / Real estate market in the Czech Republic and Great BritainKABLÁSKOVÁ, Jitka January 2010 (has links)
This diploma work is about real estate market in the Czech Republic and Great Britain. For comparison of these two markets and understanding how the current economic crisis has influenced them, I tried to compare the following indicators: house prices, inflation, average earnings, balance of trade, interest rates, homeownership and mortgage approvals. Housing bubbles in the USA have deliberately created the damage inflicted by companies shifting production abroad in an attempt to boost profits. As these bubbles burst, economic growth in many developed countries will inevitably tumble. Interviews with real estate and development Company in the Czech Republic and Great Britain helped me find out trends affecting property investment and its potentials. The marked factors which, I believe, will affect property investment prices now and in the future, are socio-economic trends, demographics, infrastructure, jobs and regeneration of the area. The property market has been changed from the market of supplier to the market of demander. Real estate and development Companies have to change their way of selling and offer complex and professional services. It is expected the real estate market will recovery slowly.
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Challenges in video game development - What does Agile management have to do with it?Westerdahl, Matilda January 2019 (has links)
The video game industry has gone through a dramatic change over the last few decades, yetseveral reports show that there are currently many challenges that developers face in their dailywork. A major challenge includes difficulties of getting projects to close within set time andresource restraints. This is something that indicates a connection to the management methodsbeing used, among which Agile management is a popular framework that many turn to. Thisthesis searches for connections between challenges in video game development and the usage ofagile methods like Scrum and Kanban. For this, a qualitative research strategy was used in orderto look into the experiences of video game developers. Five semi-structured interviews with atotal of eleven respondents were conducted. As a complement, a quantitative web-based surveywas made where 23 people participated. The results of this study show that challengespreviously defined within the video game industry, including feature creep, crunch periods anda stressful work pace can also be identified in the industry in southern Sweden to some extent.Underlying patterns indicate the industrial culture as an explanation for an incorrectimplementation of agile methods, which could eventually lead to issues surrounding riskmanagement in projects.
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Information and discrimination : foundations and applications to credit and labor markets / L'information et la discrimination : fondements et applications aux marchés du crédit et de travailLi, Yuanyuan 04 December 2015 (has links)
Cette thèse commence, en théorie, avec le caractère informatif de signaux lorsque l'information est imparfaite, suivis par les applications sur les marchés du crédit et du travail. Dans le chapitre 2 nous montrons que le critère de Blackwell peut impliquer la dispersion des espérances conditionnelles -le critère de « supermodular dispersion » proposé par Ganuza et Penalva (2010), uniquement lorsque le signal est binaire. Les liens entre la dispersion des espérances conditionnelles et le critère de Persico peuvent être construits mais avec des restrictions fortes. Dans le chapitre 3, nous considérons une relation prêteur-emprunteur où les emprunteurs peuvent choisir de divulguer l'information en payant un coût non négligeable. La décision de la révélation d'informations est endogénisée. Nous montrons qu'il existe seulement équilibre opaque (transparent) lorsque le taux d'intérêt sans risque est assez faible (élevé); il y a des équilibres multiples lorsque le taux d'intérêt est intermédiaire et resserrement du crédit peut résulter. Le modèle est ensuite étendu à un contexte OLG et nous montrons que le marché peut converger soit à un état stationnaire opaque ou transparent, et peut avoir des oscillations permanentes entre les états différents pour certaines configurations de paramètres. Dans le chapitre 4, nous étudions l'impact de la discrimination à l'embauche sur les compétences de la décision d'investissement de travailleurs dans un modèle de recherche dirigée. Le groupe discriminé ou le groupe favorisé peut sous-investir dans les compétences à l'équilibre. Chaque fois qu'un groupe de travailleurs sous-investit, l'autre groupe reste hautement qualifié et le profit des entreprises est inférieur par rapport au niveau à l'économie où la discrimination est absente. / This thesis starts, theoretically, with the informativeness of signals when information is imperfect, followed by the applications on the credit and tabor markets. In chapter 2 we show that Blackwell's informativeness criterion can imply the dispersion of the conditional expectations - the supermodular dispersion criterion proposed by Ganuza and Penalva (2010), only when the signal is binary. Links between the dispersion of the conditional expectations and Persico's accuracy criterion can be built up but with strong restrictions. In chapter 3, we consider a lender-borrower relationship where borrowers can choose to disclose their private information by paying a non-negligible cost. The decision of information revelation is endogenized, and so is the market opacity. We show that there exists only opaque (transparent) equilibrium when the safe interest rate is low (high) enough; there are multiple equilibrium when interest rate is intermediate and credit crunch may happen. The model is then extended to an OLG context and we show that the market may converge either to an opaque or a transparent stationary state, or, for some configurations of parameters, have permanent oscillations between different states. In chapter 4 we study the impact of hiring discrimination on workers' skill investment decision in a directed search model. Both the discriminated and favored group can underinvest in skills in equilibrium. Whenever one group underinvest, the other remain high skilled and firms suffer from lower profit compared to the economy where discrimination is absent.
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UNDERSTANDING VIDEO GAME DEVELOPER INTENTION VERSUS OUTCOME AS IT PERTAINS TO AUDIENCE EXPERIENCE WITH GAME NARRATIVEHannah Leone Sherwood (16448496) 03 July 2023 (has links)
<p>This paper is a qualitative study that utilizes game players to learn more about the impact of game narrative, and to use this information to understand more of its role in the production of<br>
games. Initial research into the topic revealed that many competing interests drive game production, but that if narrative was “down-prioritized” in production, a game was more likely to suffer compounding issues that could result in a poor end-product and launch. This nets monetary consequences for a studio, but also severely impacts the team of developers. As the game industry already faces widespread issues with crunch, long work hours over long periods of time, any additional strain on production exacerbates existing issues. Game production documentation is often held privately as the trade secrets of a given studio, so the most feasible way to address these questions is to seek a successful game with amble published documentation and compare those resources to the experiences players themselves have with the title. The Legend of Zelda: Breath of the Wild was the game chosen.<br>
A sample of 18 students from Purdue University completed an initial interest survey and provided demographic information. Of those who played games regularly, 4 participants were randomly selected to move forward with an audio and video recorded gameplay session that utilized a think-aloud protocol to capture moment-to-moment experience, and then an audio recorded interview about their experiences. These methods were employed to generate transcripts of their thoughts and experiences where the researcher conducted a thematic analysis of the content. Fifteen codes were synthesized from these transcripts and found that through the context of narrative, participants expressed that gameplay, aesthetics, and critical paths in a game facilitated their experiences with narrative. Participants approached the game and spoke about narrative in a variety of ways during the game session, but all came away with similar conclusions when interviewed. This suggests that game elements that convey narrative are highly effective and opens questions into how changes to those elements can sway interpretation and if that can be controlled for. Further, studying the patterns between these elements and determining what creates the most meaning for players could open new avenues for efficient game design. </p>
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Anställdas syn på en 4-dagars arbetsvecka i samband med upplevelsen av arbetskrav och work-life balance inom spelutvecklingsindustrin / Employees' view on a 4-day work week along with the experience of job demands and work-life balance within the game development industryKloft, Koralena, Susnjar, Mina January 2024 (has links)
Denna uppsats syftar till att undersöka hur synen på en 4-dagars arbetsvecka ser ut i samband med upplevelsen av arbetskrav och work-life balance hos anställda inom spelutvecklingsindustrin. Denna industri är unik för sina olika arbetsrelaterade problem, som bland annat återkommande tidsperioder med en extrem överbelastning av arbete, där 4-dagars arbetsveckan har blivit omtalad runtom i världen och anses kunna förbättra många av de utmaningar inom arbetet som spelutvecklingsindustrin i nuläget har. För att samla in data distribuerades en enkät till 120 anställda i ett svenskt spelutvecklingsföretag. Skalor om work-life balance, arbetskrav och synen på 4-dagars arbetsveckan inkluderades i enkäten, samt demografiska frågor och frågor om boendesituation och crunch. Totalt deltog 58 respondenter i undersökningen, där en deskriptiv- och korrelationsanalys gjordes av datan. Resultatet visade på ett statistiskt signifikant samband mellan synen på 4-dagars arbetsveckan och work-life imbalance, samt mellan work-life imbalance och arbetskrav. Uppsatsen har bidragit med skapandet av ett nytt mått för synen på 4-dagars arbetsveckan och diskuterar metodologiska styrkor och begränsningar i samband med resultatet och framtida forskning.
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Stochastic Credit Default Swap PricingGokgoz, Ismail Hakki 01 September 2012 (has links) (PDF)
Credit risk measurement and management has great importance in credit market. Credit derivative products are the major hedging instruments in this market and credit default swap contracts (CDSs) are the most common type of these instruments. As observed in credit crunch (credit crisis) that has started from the United States and expanded all over the world, especially crisis of Iceland, CDS premiums (prices) are better indicative of credit risk than credit ratings. Therefore, CDSs are important indicators for credit risk of an obligor and thus these products should be understood by market participants well enough. In this thesis, initially, advanced credit risk models firsts, the structural (firm value) models, Merton Model and Black-Cox constant barrier model, and the intensity-based (reduced-form) models, Jarrow-Turnbull and Cox models, are studied. For each credit risk model studied, survival probabilities are calculated. After explaining the basic structure of a single name CDS contract, by the help of the general pricing formula of CDS that result from the equality of in and out cash flows of these contracts, CDS price for each structural models (Merton model and Black-Cox constant barrier model) and CDS price for general type of intensity based models are obtained. Before the conclusion, default intensities are obtained from the distribution functions of default under two basic structural models / Merton and Black-Cox constant barrier. Finally, we conclude our work with some inferences and proposals.
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台灣信用卡,現金卡(雙卡)信貸危機(卡債)之探討 / Study the Taiwan Credit Card and Cash Card Lending Crisis趙菊香, Chao,chu- hsiang Unknown Date (has links)
近年來由於國民所得的提升、外匯增加,消費貸款相關法令鬆綁及政府政策刺激消費下,臺灣信用卡市場在外商銀行、新銀行的強力業務主導下,從1991年到2005年歷經了蓬勃發展、同業之間的激烈競爭、現金卡的發行加入競爭行列、整合型小額信用貸款的竄出,讓金融業以市場行銷為業務主導下,逐漸放鬆銀行的授信政策。在市場競爭及飽和下,消費者過度地消費和整體經濟持續低迷,終於引爆了嚴重的信用卡、現金卡逾期無法繳款的雙卡卡債問題。本研究欲從信用卡的成長、輔助現金卡的加入競爭行列,由各代表性的銀行發展中,探討出發生嚴重逾期放款的原因,再使用各銀行提供給金融監督管理委員會的重大資訊逐一分析,作為佐證之依據。
研究結果如下:
1. 銀行業為了業務成長,並未正確及適時地看待相關風險的控管,不斷的簡化辦卡程序、提高信用額度、增加信貸總額,以期增加信貸客戶數及客戶忠誠度。
2. 銀行業在擴張業務的同時沒有充分考慮到客戶的真實收入與負債比例,進而在發生嚴重的信貸危機時,違約比率不斷增加,銀行業亦承受了相當大打銷呆帳的金額。
3. 政府主導的統一債務協商機制,各銀行已逐漸從混亂中,走上標準作業,協商成功比率陸續提升中。未來卡片市場可否走向更健全:金融業、全民、主管機關都應更謹慎地處理消費者信用貸款的問題。 / Credit card market, driven by foreign banks and local new banks, had been boosting from 1991 to 2005 derived from GDP growth, hike of foreign exchange reserves, laws ease up, and government policies creating friendlier environment to boost consumer spending. In the same time, banks’ credit policies were loosened due to fierce competition among credit card issuers, issuances of cash card and integrated unsecured loan led by sales and marketing. Given the situation of over-banking and competition in credit card market, consumers overspent under the consistent economy recession triggered credit crunch for credit card and cash card, so called “Credit card and cash card lending crash”. This research intends to search for the root of this credit crunch by investigating the history of the growth of credit card business and issuance of cash card of major players in the market. Furthermore, this research also evidences the concluded root reasons by analyzing the important information reported to FSC by all the banks.
The conclusions of the investigation are as follows:
1. Banking industry overemphasized on business growth so the related risks were not properly and timely controlled by simplifying application procedures and increasing credit lines hoping to enhance number of customers and strengthen customers’ loyalty.
2. Banking industry ignored the percentage of customers’ real income and liability while expanding their business rapidly. It further deepened the delinquency ratio and card issuers wrote off enormous amount of bad debts when credit crunch happened.
3. Debt Negotiation Plan (DNP) led by government enabled banks to set up “Standard Operation Procedures” (SOP) which helped banks to resume their card business back to normal. The success ratio of DNP is increasing gradually. The future of credit card market all depends on how banking industry, consumers, and government deal with the issues on consumer unsecured loans.
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Neurofunctional reorganization to support semantic processing during aging : an fMRI studyHaitas, Niobe 11 1900 (has links)
Le langage est dans son ensemble bien préservé pendant le vieillissement (Meyer & Federmeier, 2010) tandis que la mémoire sémantique peut même s'améliorer (Kavé, Samuel-Enoch, & Adiv, 2009; Prinz, Bucher, & Marder, 2004; Salthouse, 2009; Verhaegen & Poncelet, 2013 ; Wingfield & Grossman, 2006), malgré de nombreux changements neurophysiologiques se produisant dans le cerveau (Grady, Springer, Hongwanishkul, McIntosh, & Winocur, 2006 ; Kemper & Anagnopoulos, 1989 ; Wingfield & Grossman, 2006). Cette thèse se concentre sur la préservation de la mémoire sémantique dans le vieillissement, « l'acte cognitif d'accéder aux connaissances stockées sur le monde » (Binder, Desai, Graves et Conant, 2009) à travers une tâche de jugement sémantique manipulant le contrôle sémantique avec deux niveaux de demande (faible et élevé) et deux types de relations sémantiques (taxonomique et thématique). Nous avons développé une nouvelle tâche variant les niveaux de demande (faible et élevé) chez 39 adultes jeunes et 39 adultes âgés. Plus précisément, les objectifs de notre étude étaient 1) d'identifier si le vieillissement affecte l'activité cérébrale liée à la mémoire sémantique conformément aux prédictions du modèle CRUNCH, à travers une tâche de jugement sémantique à deux niveaux d'exigences. 2) de combler le vide de la littérature sur l'existence et l'évolution des hubs sémantiques dans le vieillissement, à la lumière des théories single hub et dual-hub, en évaluant l'effet du vieillissement sur le rôle des lobes temporaux antérieurs (ATL) et du jonction temporo-pariétale (TPJ) en tant que représentations neuronales des centres sémantiques responsables respectivement du traitement taxonomique et thématique. Une soumission par rapport pré-enregistré (registered report) a été utilisée pour ce projet de recherche. Nos participants, adultes plus jeunes et plus âgés, étaient globalement appariés en termes de réserve cognitive, plus précisément en ce qui concerne le niveau d'éducation et comme le montrent les questionnaires évaluant l'engagement dans des activités cognitivement stimulantes, les tests MoCA et WAIS-III. Les résultats comportementaux ont confirmé que la tâche varie correctement la difficulté de la tâche puisque les taux d'erreur et les temps de réponse (RT) augmentent de manière linéaire avec l'augmentation des exigences de la tâche, à savoir dans la condition de forte demande. Nous avons constaté que la participation à des activités stimulantes sur le plan cognitif avait un impact positif à la fois sur les RT de référence et sur la précision. Nous n’avons pas observé de différence statistiquement significative dans la précision entre les participants jeunes et plus âgés, quelle que soit la condition. Nous avons constaté que des scores plus élevés aux tests WAIS-III et PPTT étaient positivement corrélés avec la précision chez les personnes âgées. En termes de RT, nous avons observé une différence statistiquement significative entre les participants jeunes et plus âgés pour la tâche et les conditions de référence, les adultes plus âgés étant plus lents à répondre en général. Les RT augmentent linéairement avec l'âge du participant. En tant que telle, la tâche de mémoire sémantique a réussi à a) manipuler la difficulté de la tâche sur deux niveaux d'exigences et b) démontrer une performance comportementale invariante selon l'âge pour le groupe plus âgé, comme l'exige le test du modèle CRUNCH (Fabiani, 2012 ; Schneider-Garces et al., 2010). Pour l'objectif n°1, les tests cruciaux du modèle CRUNCH, l'interaction IRMf groupe par difficulté, n'étaient pas cohérents avec les prédictions du modèle. Malgré nos résultats comportementaux, lorsque nous avons comparé directement la condition de faible demande avec la condition de forte demande, il n'y avait pas de différence statistiquement significative dans l'activation entre les conditions de faible et de forte demande. Nous n'avons pas non plus obtenu d'interaction entre tranche d'âge et difficulté. Nous avons obtenu des interactions significatives en comparant les conditions de demande faible et élevée avec la ligne de référence. Au niveau neuronal, indépendamment de l'âge, la tâche de jugement de similarité sémantique a activé un large réseau bilatéral fronto-temporo-pariétal. Pour l'objectif n°2 concernant l'effet de relation sémantique, le contraste de la condition taxonomique avec la condition thématique directement n'a pas trouvé d'activation robuste à un seuil corrigé. La condition taxonomique a donné des résultats intéressants par rapport à la condition de base. Sept groupes distincts dans le cortex fronto-temporo-pariétal ont été activés dans les deux hémisphères, y compris les lobes temporaux antérieurs (ATL) et la jonction temporo-pariétale gauche (TPJ). De plus, l'activation était significative dans le gyrus supérieur frontal gauche, le gyrus angulaire gauche (AG) et le gyrus frontal inférieur (partie orbitale) sur l'hémisphère droit. Cette découverte pourrait être en partie conforme à la théorie du double-hub, qui propose que les ATL bilatéralement et le TPJ agissent comme des hubs sémantiques. Bien que nous n'ayons pas trouvé d'activation significative dans les ATL pendant la condition taxonomique et dans le TPJ pendant la condition thématique, nous avons cependant constaté que dans la condition taxonomique parmi les sept clusters significativement activés, l'activation dans le gyrus frontal supérieur gauche était significativement corrélée avec la performance dans la condition taxonomique pour les deux groupes d'âge. L'activation dans le gyrus temporal moyen droit était également corrélée à l'amélioration des performances, mais cela n'était pas significatif dans le groupe plus âgé. En ce qui concerne la condition thématique, par contraste avec condition de référence, dix groupes distincts ont été activés, y compris la jonction temporo-pariétale (TPJ), alors que les ATL n'ont pas été activés de manière robuste pendant la condition thématique. Plus précisément, les régions activées comprenaient bilatéralement le gyrus angulaire, le gyrus temporal moyen, le gyrus frontal inférieur (partie triangulaire) et le gyrus frontal moyen. Nous visons à poursuivre des analyses supplémentaires pour explorer la relation entre les exigences de la tâche, le type de relation sémantique et la réorganisation neurofonctionnelle liée à l'âge. Cependant, ces résultats relatifs à la préservation avec l'âge des capacités à traiter les différentes relations sémantiques de mots sont associés à un certain nombre de réorganisations neurofonctionnelles. Celles-ci peuvent être spécifiques au traitement de différentes relations sémantiques et de différentes demandes de tâches. Il reste à déterminer si cette réorganisation est induite par les changements structurels du cerveau avec l'âge, ou par l'utilisation accrue de telles relations sémantiques tout au long de la trajectoire de la vie. / Language overall is well preserved in aging (Meyer & Federmeier, 2010) whereas semantic memory may even improve (Kavé, Samuel-Enoch, & Adiv, 2009; Prinz, Bucher, & Marder, 2004; Salthouse, 2009; Verhaegen & Poncelet, 2013; Wingfield & Grossman, 2006), despite numerous neurophysiological changes taking place in the brain (Grady, Springer, Hongwanishkul, McIntosh, & Winocur, 2006; Kemper & Anagnopoulos, 1989; Wingfield & Grossman, 2006). The present study focuses on the preservation of semantic memory in aging, the ‘cognitive act of accessing stored knowledge about the world’ (Binder, Desai, Graves, & Conant, 2009) by means of a semantic judgment task manipulating semantic control with two demand levels (low and high) and two types of semantic relations (taxonomic-thematic). We used a novel task that varied task demands (low versus high) in 39 younger and 39 older adults. More specifically, the aims of this study was 1) to identify whether aging affects the brain activity subserving semantic memory in accordance with the CRUNCH predictions, through a semantic judgment task with two levels of demands (low and high). 2) To bridge the gap in the literature on the existence and evolution of semantic hubs in aging, in light of the dual and single-hub theories, by evaluating the effect of aging on the role of the Anterior Temporal Lobes (ATLs) and the Temporo-parietal junction (TPJ) as neural representations of the semantic hubs responsible for taxonomic and thematic processing, respectively. A submission by registered report was opted for this research project. Our participants, younger and older adults, were overall matched in regards to level of education and as shown in questionnaires assessing engagement in cognitively stimulating activities, MoCA and WAIS-III tests. The behavioral results confirmed that the task was successful in manipulating task difficulty, with error rates and RTs increasing with increasing task demands, namely in the high-demand condition. We found that engaging in cognitively stimulating activities impacted positively on both baseline RTs and accuracy and that higher scores on the WAIS-III and the PPTT tests were positively correlated with accuracy in older adults. There was no statistical difference in accuracy between younger and older participants regardless of the condition, so there was no age effect in accuracy. In terms of RTs, there was a statistically significant difference between younger and older participants for both the task and the baseline conditions, with older adults being slower to respond in general. RTs increased the more the participant’s age increased, which is in line with findings in the literature. As such, the semantic memory task was successful in a) manipulating task difficulty across two levels of demands and b) demonstrating age-invariant behavioural performance for the older group, as requires to test the CRUNCH model (Fabiani, 2012; Schneider-Garces et al., 2010). For objective no 1, the crucial test of CRUNCH model, the fMRI age group by task demand interaction was not found. We did not find statistically significant interaction neither between task demands and age group for RTs or accuracy, nor in regards to brain activation. At the neural level, independently of age, the semantic similarity judgment task activated a large network including bilateral inferior frontal, parietal, supplementary motor, temporal and occipital brain regions, which correspond overall with the semantic network, as suggested in the literature. Region of interest analyses demonstrated task demand effect in these regions, most notably in the left and right inferior frontal gyrus, the left posterior middle temporal gyrus, the posterior inferior temporal gyrus and the pre-frontal gyrus, regions which are typically associated with semantic control requirements. We did not find any significant interactions between task demands and activation in the regions of interest either. Several possible reasons may justify the lack of findings as predicted by the CRUNCH hypothesis. For objective no 2 in regards to the semantic relation effect, the contrast of the taxonomic with the thematic condition directly did not produce any robust activation at a corrected threshold. The taxonomic condition yielded interesting results when contrasted with the baseline one. Seven distinct clusters in the fronto-temporo-parietal cortex were activated across the two hemispheres, including the anterior temporal lobes (ATLs) and the left temporo-parietal junction (TPJ). Additionally, activation was significant in the left frontal syperior gyrus, the left angular gyrus (AG) and the inferior frontal gyrus (orbital part) on the right hemisphere. This finding could be partly in line with the dual-hub theory, that proposes that the ATLs bilaterally and the TPJ act as semantic hubs. Though we did not find the expected double dissociation e.g., significant activation in the ATLs during the taxonomic condition only and in the TPJ during the thematic condition only, we found however that in the taxonomic condition among the seven significantly activated clusters, activation in the left superior frontal gyrus was significantly correlated with performance in both age groups. Activation in the right middle temporal gyrus was also correlated with improved performance, but this was not significant in the older group. During the thematic condition, when contrasted with baseline, ten distinct clusters were activated, including the temporo-parietal junction (TPJ), whereas the ATLs were not robustly activated during the thematic condition. We aim to pursue additional analyses to explore the relation between task demands, type of semantic relation and age-related neurofunctional reorganization. However, these results in relation to the preservation with age of the abiliites to process the different semantic word relations is associated with a number of neurofunctional reorganizations. These can be specific to the processing of different semantic relations and different task demands. Whether this reorganization is induced by the structural changes in the brain with age, or by the enhanced use of such semantic relations along the trajectory of life is still under exploration.
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