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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.
31

Value-based management : an application in North West regional pharmacies / L. Nel.

Nel, Lindi January 2012 (has links)
Value based management is a process that can be used to determine a business’s value drivers. It attempts to determine how the drivers link to value creation, and then break down the value drivers into achievable activities that can be pursued by employees. Due to strict medicine pricing regulations in the country, it is becoming increasingly difficult for pharmacy businesses to stay profitable. This study set out to develop a value based management framework that could be used by pharmacy management in order to maximise value creation in the business and help ensure its survival despite the strict pricing regulations. Secondary objectives were to contextualise the term “value based management”, to identify the value drivers in a pharmacy business and to determine the extent to which value based management and its principles are being applied in pharmacies in the North West region of South Africa. The research study began in the literature where the term “value based management” was introduced and a literature study was done to conceptualise the term by investigating why value based management and value creation were important. Value based management metrics, the components of value based management; and key success factors for the implementation of value based management principles were investigated. A further literature study was done to identify possible value drivers in a pharmacy business. An empirical study was conducted among registered pharmacists in the North West region of South Africa. Using the value drivers identified in the literature study as constructs, a questionnaire was designed to explore participants’ level of exposure to (and knowledge of) value based management as well as the extent to which the principles of value based management were being applied at the pharmacy businesses where participants were employed. Analysis of the responses showed the questionnaire to be reliable and valid. The results of the study highlighted that many respondents’ lack knowledge regarding the constructs (value drivers), cost price in the dispensary and cost of wages. Constructs (value drivers) that were better understood included product mix in the front shop and debtors’ control. Constructs (value drivers) that were best managed at the pharmacies where participants were employed, were cost price in the front shop and stock control. Constructs (value drivers) that were not as thoroughly managed were sales growth in the front shop and cost of wages. Conclusions regarding the findings of the research study were presented and recommendations were made. The research study was evaluated opposite the primary and secondary objectives with the conclusion that both were achieved. Finally, recommendations for further research into value based management and the application of its principles in pharmacy businesses were proposed. / Thesis (MBA)--North-West University, Potchefstroom Campus, 2013.
32

Value-based management : an application in North West regional pharmacies / L. Nel.

Nel, Lindi January 2012 (has links)
Value based management is a process that can be used to determine a business’s value drivers. It attempts to determine how the drivers link to value creation, and then break down the value drivers into achievable activities that can be pursued by employees. Due to strict medicine pricing regulations in the country, it is becoming increasingly difficult for pharmacy businesses to stay profitable. This study set out to develop a value based management framework that could be used by pharmacy management in order to maximise value creation in the business and help ensure its survival despite the strict pricing regulations. Secondary objectives were to contextualise the term “value based management”, to identify the value drivers in a pharmacy business and to determine the extent to which value based management and its principles are being applied in pharmacies in the North West region of South Africa. The research study began in the literature where the term “value based management” was introduced and a literature study was done to conceptualise the term by investigating why value based management and value creation were important. Value based management metrics, the components of value based management; and key success factors for the implementation of value based management principles were investigated. A further literature study was done to identify possible value drivers in a pharmacy business. An empirical study was conducted among registered pharmacists in the North West region of South Africa. Using the value drivers identified in the literature study as constructs, a questionnaire was designed to explore participants’ level of exposure to (and knowledge of) value based management as well as the extent to which the principles of value based management were being applied at the pharmacy businesses where participants were employed. Analysis of the responses showed the questionnaire to be reliable and valid. The results of the study highlighted that many respondents’ lack knowledge regarding the constructs (value drivers), cost price in the dispensary and cost of wages. Constructs (value drivers) that were better understood included product mix in the front shop and debtors’ control. Constructs (value drivers) that were best managed at the pharmacies where participants were employed, were cost price in the front shop and stock control. Constructs (value drivers) that were not as thoroughly managed were sales growth in the front shop and cost of wages. Conclusions regarding the findings of the research study were presented and recommendations were made. The research study was evaluated opposite the primary and secondary objectives with the conclusion that both were achieved. Finally, recommendations for further research into value based management and the application of its principles in pharmacy businesses were proposed. / Thesis (MBA)--North-West University, Potchefstroom Campus, 2013.
33

Förutsättningar för värdebaserad prissättning : En fallstudie av den svenska anläggningsbranschen / Prerequisites for value-based pricing : A case study of the Swedish construction industry

Sörensson, Robin, Sköld, Albin, Sköld, Jakob January 2014 (has links)
Titel: Förutsättningar för värdebaserad prissättning: en fallstudie av den svenska anläggningsbranschen. Datum för slutseminarium: 2014-06-03. Program: Marknadsföringsprogrammet. Författare: Robin Sörensson, Albin Sköld och Jakob Sköld. Handledare: Peter Caesar. Examinator: Dr. Pejvak Oghazi. Nyckelord: Prissättning, värdebaserad prissättning, värdeskapande, värdeappriopriering. Syfte: Syftet med denna studie är att identifiera interna och externa faktorer som påverkar prissättningen samt beskriva vilka förutsättningar för tillämpning av värdebaserad prissättning dessa faktorer ger upphov till. Teoretiskt ramverk: Det teoretiska ramverket utgår från de två olika dominerande synsätten på värdeskapande och värdeappriopriering. Forskning på prissättning i förhållande till dessa synsätt hämtas i huvudsak från Porter (1980), Dutta et al. (2003) och Hallberg (2008). Metod: Studien bygger på en kvalitativ datainsamling genom intervjuer med personer inom ett utvalt fallföretag inom anläggningsbranschen och fyra av deras återförsäljare. Empiriskt resultat: Empirikapitlet innehåller den kvalitativa datan som samlats in genom intervjuerna och presenteras i form av en tabell samt preliminär dataanalys. Analys: Utifrån empirin och det teoretiska ramverket har externa och interna faktorer som påverkar utformandet av en prissättningsstrategi identifierats. Dessa faktorer har också delats upp i drivkrafter och hinder för att klargöra vilka förutsättningar för en tillämpning av värdebaserad prissättning som finns. Detta presenteras i form av tabeller och löpande text. Slutsatser: Sammantaget har tio faktorer som påverkar prissättningen inom anläggningsbranschen identifierats och beskrivits. Sex faktorer är branschrelaterade och fyra faktorer är resursrelaterade. Det kan ses tendenser till att de externa faktorerna bidrar mer till drivkrafter och de interna faktorerna till mer av hinder för en tillämpning av en värdebaserad prissättningsstrategi. / Title: Prerequisites for value-based pricing: a case study of the Swedish construction industry. Date of final seminar: 2014-06-03. Program: Marketing program. Authors: Robin Sörensson, Albin Sköld och Jakob Sköld. Advisor: Peter Caesar. Examiner: Dr. Pejvak Oghazi. Keywords: Pricing, value based pricing, value creation, value appropriation. Purpose: The purpose of this study is to identify internal and external factors affecting the pricing as well as describe the conditions for implementation of value-based pricing that these factors gives rise. Theoretical framework: The theoretical framework is based on the two dominant approaches to value creation and value appropriation. Research on pricing in relation to these approaches retrieved mainly from Porter (1980), Dutta et al. (2003) and Hallberg (2008). Methodology: The study is based on qualitative data collection through interviews with people within a selected case companies in the construction industry and four of their dealers. Empirical results: Empirical chapter includes the qualitative data collected through interviews and presented in tabular form as well as a preliminary data analysis. Analysis: Through the empirical result and the theoretical frameworks, external and internal factors affecting the design of a pricing strategy has been identified. These factors have also been divided into drivers and barriers to clarify the requirements for the application of value-based pricing that is available. This is presented in the form of tables and scrolling text. Conclusions: Overall, ten factors that affects the pricing of the construction industry has been identified and described. Six factors are industry-related and four factors are resource-related. Tendency’s can also been seen for that the external factors contributing more to the driving forces and the internal factors of more obstacles to the application of a value-based pricing strategy.
34

Value-based management : shareholder value creation and management / Christoff Greyling.

Greyling, Christoffel Jacobus Coetzer January 2010 (has links)
The objective of this study is to evaluate the value drivers that drive the value of companies, as reflected in the share-prices. Through this study, the aim is to draw conclusions on the aspects that drive the share-price of companies. A detailed literature study was performed on the value-creation process that takes place in a company. The literature study has a significant focus on Value-Based Management and the elements that should be considered when evaluating the manner in which companies create shareholder value through the operational activities that are performed. Through applying the principles of value-based management, the management of companies should maximise the value-created for shareholders by utilising company resources in the most effective and efficient way possible. Valuebased management should not be seen as a once-of initiative, but should be ingrained in the day-to-day operating and management activities of companies. The objective of applying value based management principles in a company should be to enhance the value of financial assets through the optimisation of the real assets of the company. Value is created in a company when the company can maintain a return on capital that is greater than the cost of capital. Through the literature study several value-drivers were identified that influence the shareholder value-creation process and that should be managed optimally. These value-drivers have been identified to be (1) sales growth, (2) cash profit margin - earnings before interest, tax, depreciation and amortisation (EBITDA), (3) cash tax rate, (4) working capital, (5) capital expenditure, (6) WACC- the risk and inflation adjusted weighted average cost of capital, and (7) the competitive advantage period. The competitive advantage period is defined as the time during which a company has a positive net present value when discounted at the WACC. Any actions that the management of a company can take to optimise these value-drivers will have a positive effect on the value created for shareholders. The link between shareholder value-creation and share-price was investigated in the literature study. It was found that different factors influence share prices and that some have nothing to do with the company itself, but more with investor sentiment about the economy as a whole and other socio-political factors. The empirical study was based on analysing key value-drivers and financial ratios that were identified during the literature study, in order to establish the relationship between company value-creation and the share-price. The data sample that was used in the empirical study consisted of 55 publicly listed companies that had a net asset value of one billion rand (R1, 000,000,000) or more in 1998. This data sample parameter was chosen in order to consider companies in the empirical study that have significant market presence in the respective industries, sectors and sub-sectors. The time horizon of the empirical study was over a 1 0-year period, from 1998 to 2007. The relationship that exists between the dependent variables of (1) Average Share Price (ASP) and (2) Year-End Share Price (YESP) and the independent variables of (1) net assets, (2) turnover, (3) trading profit, (4) operating profit, (5) profit before interest and tax, (6) Net Operating Profit After Tax (NOPAT), (7) retained profits, (8) free cash flow, (9) Economic Value-Added (EVA), (1 0) Earnings Per Share (EPS), (11) Cash Flow Per Share (CFPS), (12) the price earnings ratio, (13) operating assets, (14) Return On Assets (ROA), and (15) Return On Equity (ROE) were analysed during the empirical study. These dependent and independent variables were chosen based on the insights gained through the literature study and was identified as appropriate to formulate conclusions on the relationship that exists between shareholder value-creation and share-price. The distributions of the above-mentioned variables are discussed in detail and distribution figures are provided to contextualise the spread of the variables and provide background on the data that was used in the empirical study. Although the study of the variables was conducted over a 1 0-year period, from 1998 to 2007, distribution figures for the years 1998 and 2007, are depicted and discussed in order to provide a comparison of the changes that took place over the 1 0-year period. Due to the nature of the variables analysed during the empirical study, the Spearman Rank Correlation Coefficient is used to measure the relationship that exists between the dependent and independent variables. The Spearman Rank Coefficient is a factor model that explains complex phenomena through a small number of basic causes or factors. Given the relative large number of shares available on the share market, the estimation of dependent, share-price variables cannot be performed without simplification to dimensionality, therefore the use of the Spearman Rank Coefficient. The coefficient of correlation between the dependent and independent variables was calculated for the each of the years over the 1 0-year period and the applicability to explain the relationship between shareholder value-creation and share-price was analysed. Through the statistical analyses and the interpretation of the results, it was concluded that earnings per share and cash flow per share are the most appropriate indicators for estimating the relationship that exists between shareholder value-creation and the share-price as reflected on the share market. / Thesis (M.B.A.)--North-West University, Vaal Triangle Campus, 2010.
35

Superior investment returns : the role of value-based investment / R.A. Janse van Rensburg.

Janse Van Rensburg, Roedolf Arnoldus January 2009 (has links)
The strong form of the efficient market hypothesis (EMH) puts forward that it is impossible to achieve better than market results. Yet there are very famous investors, particularly a famous value based investor named Warren Buffett that have achieved better than market returns. The primary objective of this study is to investigate the role of value based investment in generating better than market or superior investment returns. The study was conducted both as a literature study and an empirical study. The objectives of the literature study were threefold. Firstly, to discover value based investment as part of a discussion on investment strategies. Secondly, to investigate the possibility of achieving better than market returns. Lastly, to investigate the role of value based investing in achieving better than market returns. Through the literature study, value based investment parameters were also identified for empirical testing. It was found in the literature that value based investing has a role to play in achieving superior returns. By way of the application of correlation-based research, as well as regression analysis it was found that there is significant statistical evidence to underscore that value based investment parameters can lead to superior returns. / Thesis (M.B.A.)--North-West University, Vaal Triangle Campus, 2010.
36

Value-based management : shareholder value creation and management / Christoff Greyling.

Greyling, Christoffel Jacobus Coetzer January 2010 (has links)
The objective of this study is to evaluate the value drivers that drive the value of companies, as reflected in the share-prices. Through this study, the aim is to draw conclusions on the aspects that drive the share-price of companies. A detailed literature study was performed on the value-creation process that takes place in a company. The literature study has a significant focus on Value-Based Management and the elements that should be considered when evaluating the manner in which companies create shareholder value through the operational activities that are performed. Through applying the principles of value-based management, the management of companies should maximise the value-created for shareholders by utilising company resources in the most effective and efficient way possible. Valuebased management should not be seen as a once-of initiative, but should be ingrained in the day-to-day operating and management activities of companies. The objective of applying value based management principles in a company should be to enhance the value of financial assets through the optimisation of the real assets of the company. Value is created in a company when the company can maintain a return on capital that is greater than the cost of capital. Through the literature study several value-drivers were identified that influence the shareholder value-creation process and that should be managed optimally. These value-drivers have been identified to be (1) sales growth, (2) cash profit margin - earnings before interest, tax, depreciation and amortisation (EBITDA), (3) cash tax rate, (4) working capital, (5) capital expenditure, (6) WACC- the risk and inflation adjusted weighted average cost of capital, and (7) the competitive advantage period. The competitive advantage period is defined as the time during which a company has a positive net present value when discounted at the WACC. Any actions that the management of a company can take to optimise these value-drivers will have a positive effect on the value created for shareholders. The link between shareholder value-creation and share-price was investigated in the literature study. It was found that different factors influence share prices and that some have nothing to do with the company itself, but more with investor sentiment about the economy as a whole and other socio-political factors. The empirical study was based on analysing key value-drivers and financial ratios that were identified during the literature study, in order to establish the relationship between company value-creation and the share-price. The data sample that was used in the empirical study consisted of 55 publicly listed companies that had a net asset value of one billion rand (R1, 000,000,000) or more in 1998. This data sample parameter was chosen in order to consider companies in the empirical study that have significant market presence in the respective industries, sectors and sub-sectors. The time horizon of the empirical study was over a 1 0-year period, from 1998 to 2007. The relationship that exists between the dependent variables of (1) Average Share Price (ASP) and (2) Year-End Share Price (YESP) and the independent variables of (1) net assets, (2) turnover, (3) trading profit, (4) operating profit, (5) profit before interest and tax, (6) Net Operating Profit After Tax (NOPAT), (7) retained profits, (8) free cash flow, (9) Economic Value-Added (EVA), (1 0) Earnings Per Share (EPS), (11) Cash Flow Per Share (CFPS), (12) the price earnings ratio, (13) operating assets, (14) Return On Assets (ROA), and (15) Return On Equity (ROE) were analysed during the empirical study. These dependent and independent variables were chosen based on the insights gained through the literature study and was identified as appropriate to formulate conclusions on the relationship that exists between shareholder value-creation and share-price. The distributions of the above-mentioned variables are discussed in detail and distribution figures are provided to contextualise the spread of the variables and provide background on the data that was used in the empirical study. Although the study of the variables was conducted over a 1 0-year period, from 1998 to 2007, distribution figures for the years 1998 and 2007, are depicted and discussed in order to provide a comparison of the changes that took place over the 1 0-year period. Due to the nature of the variables analysed during the empirical study, the Spearman Rank Correlation Coefficient is used to measure the relationship that exists between the dependent and independent variables. The Spearman Rank Coefficient is a factor model that explains complex phenomena through a small number of basic causes or factors. Given the relative large number of shares available on the share market, the estimation of dependent, share-price variables cannot be performed without simplification to dimensionality, therefore the use of the Spearman Rank Coefficient. The coefficient of correlation between the dependent and independent variables was calculated for the each of the years over the 1 0-year period and the applicability to explain the relationship between shareholder value-creation and share-price was analysed. Through the statistical analyses and the interpretation of the results, it was concluded that earnings per share and cash flow per share are the most appropriate indicators for estimating the relationship that exists between shareholder value-creation and the share-price as reflected on the share market. / Thesis (M.B.A.)--North-West University, Vaal Triangle Campus, 2010.
37

Superior investment returns : the role of value-based investment / R.A. Janse van Rensburg.

Janse Van Rensburg, Roedolf Arnoldus January 2009 (has links)
The strong form of the efficient market hypothesis (EMH) puts forward that it is impossible to achieve better than market results. Yet there are very famous investors, particularly a famous value based investor named Warren Buffett that have achieved better than market returns. The primary objective of this study is to investigate the role of value based investment in generating better than market or superior investment returns. The study was conducted both as a literature study and an empirical study. The objectives of the literature study were threefold. Firstly, to discover value based investment as part of a discussion on investment strategies. Secondly, to investigate the possibility of achieving better than market returns. Lastly, to investigate the role of value based investing in achieving better than market returns. Through the literature study, value based investment parameters were also identified for empirical testing. It was found in the literature that value based investing has a role to play in achieving superior returns. By way of the application of correlation-based research, as well as regression analysis it was found that there is significant statistical evidence to underscore that value based investment parameters can lead to superior returns. / Thesis (M.B.A.)--North-West University, Vaal Triangle Campus, 2010.
38

Výkonnost a hodnotové řízení firmy / Enterprise Efficiency and Value-based Management

KYSELA, Jan January 2007 (has links)
This paper deals with theory of measuring enterprise performance in relation to its market value. Main objective is to explain the principles of value-based management and answer the question why managers prefer this concept of financial management. It is extended about less used financial performance indicators which respects principles of value-based management and implements to this traditional instrument new dynamic components. This theory is supported by case study.
39

The pragmatics of confidence in perceptual and value-based choice

Folke, Nils Erik Tomas January 2018 (has links)
Humans can often report a subjective sense of confidence in a decision before knowing its outcome. Such confidence judgements are positively correlated to accuracy in perceptual and memory tasks, but the strength of this relationship (known as metacognitive accuracy) differs across people and contexts. Computationally, confidence judgements are believed to relate to the strength of evidence favouring each option, but it has been suggested that confidence also captures information from other sources, such as response time. This thesis explores the pragmatics of confidence: what factors influence confidence judgements, how accurate confidence judgements are, and how they might influence future behaviour. Our knowledge of the antecedents of confidence is extended by this work in two ways, by introducing novel predictors of confidence and by increasing our understanding of well-known ones. I find that bilinguals have worse metacognitive accuracy than monolinguals. This bilingual deficiency in metacognitive accuracy cannot be explained by response time and stimulus strength, suggesting that there is at least one important predictor of confidence that remains unaccounted for. I introduce such a predictor in a new eye tracking correlate of confidence: Gaze-shift-frequency, the number of saccades between options, negatively predicts subsequent confidence in perceptual and value-based decisions. In the value domain, the total value of the options is shown to positively relate to confidence despite being negatively related to accuracy, the first such dissociation to be recorded, as far as I am aware. The dissertation extends our understanding of response time as a predictor of confidence by showing that it influences confidence more for judgements that are made after a choice, relative to those made simultaneously with the choice. This differential influence of response time explains the higher metacognitive accuracy of sequential confidence reports. I explore the consequences of confidence judgements in the context of value-based choice. Lower levels of confidence are associated with changes of mind when the same options recur in subsequent trials. To test whether these changes of mind are rational, I approximate choice accuracy in the value domain. I propose a novel method based on the transitivity of the full choice set, so that choices that violate the most transitive ordering of the items can be treated as errors. I find that participants who were more metacognitively accurate showed a decrease in transitivity violations over time. These results extend prior work linking confidence judgements to error correction in the perceptual domain.
40

Nicotine-induced modifications in value-based decision-making / Les modifications induites par la nicotine dans la prise de décision fondée sur les valeurs

Dongelmans, Marie Louise 03 October 2017 (has links)
La dépendance à la nicotine est un problème sociétal majeur. De nombreuses personnes continuent à fumer, malgré des conséquences négatives pour la santé bien connues. La recherche sur la toxicomanie se concentre généralement sur la motivation à obtenir cette drogue, le sevrage, rendu difficile par les symptômes de manque et la persistance des comportements appris. Au cours de cette thèse, je me suis concentrée sur les interactions entre les systèmes dopaminergique et nicotinique dans les comportements de prise de décision. Je me suis particulièrement intéressée aux effets de la nicotine administrée passivement de manière chronique. Mettre en évidence les modifications dans la signalisation dopaminergique, et les altérations des comportements de choix qu'implique la consommation de drogue, permet un autre éclairage sur l'état de dépendance, mais ouvre aussi de nouvelles perspectives sur le traitement des addictions et sur les notions de vulnérabilité et de comorbidité avec d'autres pathologies. Les théories de la prise de décision suggèrent que les individus analysent les bénéfices et les coûts potentiels pour guider leurs actions. Ainsi, faire des choix appropriés nécessite d'apprendre la valeur des options disponibles à partir de l'expérience. Ce processus reposerait principalement sur l'activité des neurones dopaminergiques. Une question cruciale est de savoir si les processus computationnels sous-jacents aux choix peuvent être modifiés de manière durable par l'exposition à la nicotine et/ou par la manipulation des récepteurs nicotiniques. Nous avons développé un paradigme comportemental, de type bandit manchot avec des stimulations intra-crâniales comme récompenses, qui permet d'évaluer la prise de décision basée sur la valeur et l'exploration. Nous avons étudié le rôle de la transmission nicotinique dans l'équilibre comportemental entre exploration et exploitation à l'aide de souris knock-out pour la sous-unité beta2 du récepteur nicotinique. Nous démontrons que les souris beta2KO explorent moins que les souris de type sauvage suggérant un rôle des nAChR dans la traduction de l'incertitude attendue en motivation à explorer. Dans une deuxième étape, nous analysons l'effet d'une exposition chronique à la nicotine sur ces processus de prise de décision. Il a été proposé que la libération phasique de dopamine serait cruciale pour l\'apprentissage, alors que l'activité tonique serait plus impliquée dans l'expression d'un comportement précédemment acquis. Nous montrons ici que la nicotine, sur le long terme, peut altérer l'activité spontanée des cellules dopaminergiques et ainsi modifier la libération phasique et tonique de dopamine. Cette modification se traduit par une augmentation de la "sensibilité à la valeur", et donc une altération des choix. Un individu sous nicotine chronique se concentre davantage sur les récompenses plus importantes. Nous avons mimé cet effet par une activation optogénétique tonique des neurones dopaminergiques. Ces travaux mettent en lumière les mécanismes qui sous-tendent les changements dans la prise de décision lors d'une exposition aux drogues. / Nicotine addiction is a major societal dilemma: despite the well-known adverse consequences to health, more than one billion persist in the habit. Much addiction research focuses on the motivation to obtain and take drugs and the difficulties of abstinence due to withdrawal effects and learned behaviour. My research focuses on the interactions between the dopaminergic and nicotinic systems in value-based decision-making behaviour, as well as the effects of passively administered nicotine within this framework. Understanding the alterations in the dopamine (DA) system and choice behaviour occurring with drug consumption provides another angle on the addictive state, the general predispositions and vulnerabilities for co morbid disorders. This knowledge could unveil new perspectives towards addiction treatment. Theories of decision-making suggest that individuals analyse potential benefits and costs to guide their actions based on experience. A multitude of studies have drawn links between DA cell activity and such choice behaviour. Dopamine signals attribute to the evaluation of available options to select future actions. The addictive nature of nicotine is well established, but can a much more alarming link be made between its effect on the DA system and fundamental perception of our environment ? Could basic computations underlying choices be significantly modified by drug exposure and/or by the manipulation of nicotinic receptors ? We designed a behavioural paradigm that allows us to assess value-based decision-making in different mouse models and with different manipulations of the cholinergic-dopaminergic circuits. We investigated the role of nicotinic transmission in the exploration/exploitation tradeoff using a beta2 subunit-containing nicotinic acetylcholine receptor knockout mouse model. Using a spatial version of a three-armed bandit task and intra-cranial self-stimulation as reward, we demonstrate that beta2KO mice explore less than the WT. This finding suggests the role of specific nAChRs in the translation of expected uncertainty into motivational value and exploratory decision-making. Secondly, we analysed the effect of chronic nicotine exposure in this decision process. It has been proposed that phasic dopamine release could provide a teaching signal necessary for learning, while tonic dopamine levels could influence the implementation of previously learned behaviours. Here we show that long-term nicotine exposure can alter the spontaneous activity of VTA DA cells and therefore change phasic and tonic DA signalling. These modifications translate into an enhanced value-sensitivity; the ability to discriminate between different values. We replicated this effect through optical stimulation of VTA DA neurons on a high tonic frequency. This illustrates that organisms under chronic nicotine focus on higher rewards. This data sheds a new light on the mechanisms underlying drug-induced changes in decision-making.

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