Impulsivity and the effectiveness of a mindfulness-based intervention were explored in relation to improving behavioural self-regulation in adolescents with behavioural, emotional and social difficulties (BESD). A computerised choice task (CCT) was developed to measure delay discounting (a shift in choice from a larger reward to a smaller reward as the delay to the larger reward increases) in adolescents with BESD and compared it with several additional measures of impulsivity. The degree to which impulsivity and thoughts are related was explored using mindfulness measures. Effects of task type (computer versus sand-timer) and task context (school versus house) were also studied. Results suggested an effect of method but not location on discounting. Few between measure comparisons were significant, suggesting the possibility that different impulsivity measures assess different forms of impulsivity. However a significant negative correlation was found between impulsivity and mindfulness. A mindfulness-based intervention was implemented and results suggest potentially beneficial effects of applying mindfulness training to improve self-control and self-regulation in adolescents with BESD. Further research is necessary to determine the effectiveness of mindfulness training in adolescents with BESD, and explore differences between impulsivity measures to assist with effective measurement and intervention.

Doctor of Philosophy / Department of Psychology / Jerome Frieman / The present experiment investigated whether dwarf hamsters (Phodopus campbelli) demonstrate temporal discounting. This was investigated by comparing the behavior of dwarf hamsters and Sprague-Dawley rats (Rattus norvegicus) in an adjusting delay procedure and applying the theory of behavioral economics to explain the resulting behavior. Dwarf hamsters demonstrated temporal discounting and tolerated longer delays than did the more impulsive rats. There was not a statistically significant difference between these species concerning indifference points. There was a statistically significant difference in the slopes of their discounting functions and the delay at which the end criterion was met. Neither species exhibited sex differences with respect to these measures nor with storage of food. There were a number of differences between the species. Rats started responding quickly, whereas dwarf hamsters waited significantly longer. When faced with increasing delays, rats increased the number of pellets earned while dwarf hamsters earned the same amount. Finally, rats lost weight throughout the experiment while dwarf hamsters gained weight. There were also a number of similarities. When faced with an increasing delay, both rats and dwarf hamsters increased the number of responses made, and increased the number of times they timed out on Larger Later trials. Some of these findings disagree with previous research and predictions of the behavioral economic theory of demand, creating a need for further research.

This thesis deals with the differences in time preferences, individual discount rates, among non-Romany (Czechs) and Romany ethnic group in the Czech Republic. Subjects of almost homogenous ethnic groups -- low income, low education, currently unemployed -- were subjected to experiments based on an in-depth questionnaire (Romany N = 35, N = 25 non-Romany). In addition to time preferences, their relationship with the socio-economic and demographic characteristics was inspected. The sub-tests showed a difference across ethnic groups in regard to the discounting models. Romany ethnic group is better characterized by an inconsistent model compared to the non-Romany using an more consistent model. Participants from both groups, however, appear to be very impatient, with discount rates closer to the values of individuals dependent on addictive substances. Probably because of insufficient sample size, no statistically significant correlation was found between the discount rates and socio-economic and demographic factors. Financial (il)literacy among Romany proved to be an important factor affecting the formation of savings. Finally, the recorded signal effect of expenditures on signal goods among the Romany ethnic group is briefly analyzed.

Abstract

A tomada de decisão quase sempre envolve a dimensão temporal e no ser humano, como nos outros animais, há um viés em favorecer o presente, fenômeno chamado de desconto do futuro. Entender em que condições e contextos os vieses cognitivos como o desconto do futuro ocorrem nos ajuda a compreender o funcionamento da cognição humana, e pode fornecer caminhos para prevenir a sua ocorrência quando são prejudiciais. Há pouco consenso sobre os antecedentes psicológicos do desconto do futuro, e o nível em que ele ocorre varia conforme a espécie, o sexo, a idade, os indivíduos, e os diferentes contextos para o mesmo indivíduo. Há poucos estudos que investigam a relação entre escolhas intertemporais e a percepção subjetiva do tempo. Para compreender o fenômeno do desconto do futuro e os mecanismos psicológicos relacionados a ele, nesse estudo investigamos a influência da percepção subjetiva de tempo. Participaram 208 pessoas, 117 mulheres e 91 homens com idades entre 18 e 71 anos, que responderam a um questionário online, anônima e voluntariamente. Foram perguntados o gênero, a idade, escolaridade, estado civil, se o participante possuía ou não filhos e em seguida o participante respondia a quatro instrumentos: (1) Cenário do Cupom, para verificar a taxa de desconto do futuro, com quatro condições experimentais que corresponderam a diferentes modos de apresentação do intervalo de tempo de três meses, (2) Aversão ao Risco, para verificar a aversão ao risco e (3) Distância da data e (4) Zimbardo Time Perspective Inventory ZTPI, para verificar a percepção subjetiva de tempo. Não foi encontrada diferença significativa na taxa de desconto do futuro entre as quatro condições experimentais, contudo foi encontrada uma correlação positiva entre taxa de desconto do futuro e distância subjetiva da data em geral, juntando-se os quatro grupos e independente da apresentação. As análises indicaram que as mulheres dessa amostra apresentam maior taxa de desconto do futuro, são mais avessas ao risco, e mais propensas à orientação temporal do futuro. Os jovens, apresentaram, com relação aos mais velhos, maior taxa de desconto do futuro e maior propensão ao tempo presente. Além da distância subjetiva temporal, as variáveis gênero e idade foram as únicas que correlacionaram com diferenças na taxa de desconto do futuro. O instrumento Cenário do cupom pode não 7 ter sido adequado para acessar a taxa de desconto do futuro dos participantes quando se considera o gênero, já que outros fatores podem ter causado o maior valor pedido, e não uma maior propensão ao presente / Every moment we have to decide, and during this process cognitive biases can occur. Decision making almost always includes the temporal dimension. Human beings and other animals prefer the present, phenomenon known as future discounting. There is almost no consensus about the psychological antecedents of future discounting. Its occurrence varies with the species, the individual, the gender, the age, and different contexts for the same individual. We can understand the functioning of human mind studying the cognitive biases and the context of their occurrence, moreover we can prevent their occurrence when they are prejudicial. There are not many studies on intertemporal choice and time perception, therefore we want to contribute to the literature, adding data and reflections in this area. We explored the time perception, trough four experimental conditions, and controlling gender, age, marital status and if the participant had children or not. We had 208 participants, 117 women and 91 men, ages varying from 18 and 71, which answered to an anonymous online questionnaire, voluntarily. There were four instruments, one to verify the discounting future rate (Gift certificate Scenario ) with four experimental conditions corresponding to four different ways of presenting the three months interval , one to verify risk aversion (Risk aversion), and two to verify time perception (Distance to the date, Zimbardo time perspective inventory). There was no difference in the four experimental conditions; women had a higher future discounting rate than men, and younger participants had a higher discounting rate than older participants. Women were more risk averse than men. Younger participants had more propensity to the present than older participants. Women had more propensity to the future than men. The higher the discounting rate, higher the subjective distance of the date. There were no influence of the way the date is present, neither the participant´s marital status or if the participant had children or not. Age and gender showed an influence in time perception and future discounting

This thesis makes a contribution to that part of the economics literature that explores how behavioural economics can inform environmental economics. Theoretically, the thesis develops the concept of environmental morale. Empirically, the study investigates the role of environmental morale on individuals’ behaviour within two different contexts: recycling participation and intertemporal choices over different goods (i.e., money, environment, and health) and outcomes (i.e., gains and losses). Major objectives of this analysis are: to shed light on how environmental morale interplays with individuals’ behaviour under different recycling policy schemes, and to examine whether temporal discounting is domain specific and depends on environmental morale heterogeneity. Original survey investigations are employed to analyse these issues. Results highlight the relevance of environmental morale both in motivating individuals’ contribution to recycling and intertemporal choices towards environmental outcomes. Regarding the interaction between environmental morale, recycling participation and government interventions, results from this analysis suggest that a facilitating nudge policy seems to be relatively more powerful in increasing individuals’ contribution and motivation towards recycling. Considering intertemporal choices, a paradox of hyperopia seems to be located in data provided in this analysis. Some of the original contributions of the thesis are, first the broader reconceptualization of the definition of environmental morale and its operationalization in analyses of questionnaire preferences. Secondly, in line with other areas of research (i.e., tax compliance literature); this study pursues an investigation of individual and cultural differences with respect to recycling policies, an area which has been neglected in the environmental economics literature. In this regard, the analysis considers a comparison between psychology and economics students in Italy and the UK. Thirdly, conditioning discounting on environmental morale offers a unique opportunity to analyse how ethical considerations influence the way individuals form expectations on (near and far distant) future environmental outcomes.

Desvalorização pelo atraso (DA) se refere à preferência por gratificações menores e disponíveis imediatamente, em detrimento de gratificações maiores, disponíveis depois de algum tempo. Altos índices de DA se associam positivamente à impulsividade e estão presentes em dependentes químicos e em outros transtornos que envolvem impulsividade. Com o objetivo de conhecer melhor a DA no contexto do tabagismo na gestação, foram elaborados quatro estudos. Os dois primeiros, Desvalorização temporal: conceitos e medidas e Desvalorização pelo atraso, dependência química e impulsividade são estudos de revisão que descrevem a DA e suas características, suposições, conseqüências, relação com as dependências químicas e formas de intervenção. O estudo Atitudes de gestantes e da população geral quanto ao uso de substâncias durante a gestação mostra como gestantes e população geral pensam o uso de álcool, de cigarros e de outras substâncias durante os períodos de gestação e de amamentação, investigados através de uma enquete com cenários hipotéticos, sendo a maioria dos participantes restritiva ao uso de álcool, de cigarros e de substâncias nos dois momentos, e os permissivos condicionaram à redução de freqüência e doses. No estudo Uso de cigarros, DA e características sociodemográficas em gestantes, gestantes fumantes foram comparadas a ex-fumantes e a não fumantes com o objetivo de identificar as características do tabagismo na gestação e a DA, através de uma tarefa computadorizada, sendo controladas variáveis sóciodemográficas, estresse, transtornos mentais e uso de substâncias. Entre as fumantes, foram controlados nível de dependência do cigarro, urgência em fumar e crenças associadas ao tabagismo. Foram identificados fatores associados ao tabagismo na gestação tais como baixa escolaridade, multiparidade e parceiro fumante, sem relação entre tabagismo na gestação e estresse ou transtornos mentais. Gestantes fumantes foram as que apresentaram maior DA na situação de ganhos, demonstrando maior impulsividade. Não houve diferenças entre os grupos na situação de perdas. Os artigos são discutidos ao final da tese. / Delay discounting (DD) refers to choosing smaller and immediately available rewards, instead of larger rewards available after some time. DD relates positively to impulsivity and is present in patients with various types of addictions and other disorders involving impulsivity. Four articles were drafted aiming the understanding of DD in the context of smoking during pregnancy. The first two articles, DD, concepts and measures and DD, drug addiction and impulsivity are review studies that describe DD and its characteristics, assumptions, consequences, relation to drug addictions and intervention. The article Attitudes of pregnant women and other adults toward the use of psychoactive substances during pregnancy draws, through a survey made of hypothetical scenarios, the ideas of pregnant women and the general population on the use of alcohol, cigarettes and other substances during pregnancy and breastfeeding. Most participants showed restrictions to the use of alcohol, cigarettes and substances on both occasions, with the more permissive ones conditioning the use to less frequency of use and smaller doses. In the study Pregnant women: cigarette use, DD and socioemographic variables, aiming to identify the characteristics of smoking in pregnancy and DD, pregnant women were compared to both former smokers and non-smokers. A computer task was devised were sociodemographic variables, stress, mental disorders and substance use were taken into account. Low education (incomplete high school), having more than one children and a partner who smokes were social demographic variables significantly related to smoking during pregnancy. Stress and TMCs were not related to smoking during pregnancy. Those who smoked showed a steeper DD curve in gains but not in losses. Articles are discussed at the end of the thesis.

A number of theories have attempted to explicate mechanisms underpinning the transition from recreational drug use to substance dependence. A highly reliable correlate of dependence is the value ascribed to the drug. However, supernormal drug valuation may be insufficient to fully account for a subgroup of dependent individuals for whom the course of dependence is chronic and relapsing and who persist in drug use in the face of devastating costs. Three candidate secondary mechanisms for dependence are considered in this thesis: cue reactivity, cost discounting, and sensitivity to negative affect. Neither cue reactivity nor cost discounting were found to be significantly associated with severity of alcohol dependence in samples of young adult drinkers. By contrast, induced negative affect was found to be reliably associated with augmented alcohol motivation, and sensitivity to this effect was related to symptoms of depression and self-reported drinking to cope with negative affect: both risk factors for the development of dependence. These findings delineate a particular subset of dependent individuals for whom negative affect may represent a substantial trigger to continued drug use. There are a lack of brief interventions to abolish or limit negative affect driven drug motivation. This thesis trialled three potential interventions. A natural walk intervention in hazardous drinkers showed no evidence of limiting this effect in two experiments. Brief instruction in acceptance-based coping showed no evidence of limiting annoyance in response to an aversive noise induction procedure in an alcohol dependent population, and was therefore also eliminated as a potential intervention. However, engagement with pleasant environmental images, as a proxy for environmental enrichment, significantly reduced negative affect driven alcohol choice in student drinkers who reported a desire to visit the locations shown (high liking), compared to low-liking individuals and controls. This provides preliminary evidence for the efficacy of environmental enrichment type interventions, justifying further trials. In treatment of dependence more generally, interventions to increase access to healthy, non-drug sources of positive reinforcement may prove effective.

The endowment effect occurs when owners assign more value to the products they own than do non-owners to the same products. Research on the endowment effect has identified factors that enhance or mitigate the effect, such as the duration of ownership, as well as information processing differences between sellers and buyers. However, these studies have primarily involved immediate transactions between sellers and buyers. An interesting question emerges as to whether the endowment effect will be observed for temporally distant transactions. The main purpose of the first two studies is to examine how the temporal distance from transactions influences customers' evaluations of products by comparing buyers' willingness to pay and sellers' willingness to accept in the present and future. Despite the fact that consumers often collect information today about product or services that will be consumed in the future, such as window shopping or looking at houses or cars for a future purchase, a limited number of endowment studies have considered the temporal effect on willingness to pay and willingness to accept. More specifically, studies 1, 2, and 3 find that the endowment effect disappears as temporal distance from the transaction increases. Study 2 and 3 demonstrates that when the transaction is expected to occur in the near future, sellers focus on their products, while buyers focus on their money. These different cognitive perspectives affect price gaps between sellers and buyers. Specifically study 2 demonstrates that when events are in the distant future, sellers' and buyers' cognitive perspectives change, and the endowment effect is eliminated. In study 3, the effects of role and time on memory trace and information structure were investigate to investigate the salience differences in transaction. Finally, the underlying psychological and temporal mechanism driving the salience differences investigated in study 4-a and 4-b.

Preference for smaller-sooner over larger-later rewards characterizes one type of impulsivity—impulsive choice. Impulsive choice is related to a number of maladaptive behaviors including substance abuse, pathological gambling, and poor health behaviors. As such, interventions designed to reduce impulsive choice may have therapeutic benefits. The purpose of this dissertation was to explore two methods to change nonhuman impulsive choice. In doing so, we hope to provide a baseline that future research can use to assess variables that are less amenable to human research (e.g., drug self-administration following reductions in impulsive choice). In Chapter 2, we failed to reduce nonhuman impulsive choice using working-memory training, a finding both inconsistent and consistent with the extant human literature. Chapters 3-5 sought to better understand a training regimen that generates large between-group differences in nonhuman impulsive choice—delay- and immediacy-exposure training. The results from Chapters 3 and 4 suggest that prolonged exposure to delayed food rewards produces large and long-lasting reductions in impulsive choice. Chapter 5 showed that the delay-exposure training effect can be obtained in fewer sessions than has previously been employed. A better understanding of the effects of delay-exposure training on nonhuman impulsive choice may have implications for the design and implementation of a human analog.