Optimal portfolio choice under loss aversion

NARCIS (Netherlands)

A.B. Berkelaar (Arjan); R.R.P. Kouwenberg (Roy)

2000-01-01

textabstractProspect theory and loss aversion play a dominant role in behavioral finance. In this paper we derive closed-form solutions for optimal portfolio choice under loss aversion. When confronted with gains a loss averse investor behaves similar to a portfolio insurer. When confronted with

Colour Separation and Aversion

Directory of Open Access Journals (Sweden)

Sarah M Haigh

2012-05-01

Full Text Available Aversion to achromatic patterns is well documented but relatively little is known about discomfort from chromatic patterns. Large colour differences are uncommon in the natural environment and deviation from natural statistics makes images uncomfortable (Fernandez and Wilkins 2008, Perception, 37(7, 1098–113; Juricevic et al 2010, Perception, 39(7, 884–899. We report twelve studies documenting a linear increase in aversion to chromatic square-wave gratings as a function of the separation in UCS chromaticity between the component bars, independent of their luminance contrast. Two possible explanations for the aversion were investigated: (1 accommodative response, or (2 cortical metabolic demand. We found no correlation between chromaticity separation and accommodative lag or variance in lag, measured using an open-field autorefractor. However, near infrared spectroscopy of the occipital cortex revealed a larger oxyhaemoglobin response to patterns with large chromaticity separation. The aversion may be cortical in origin and does not appear to be due to accommodation.

Mathematical Modeling for Risk Averse Firm Facing Loss Averse Customer’s Stochastic Uncertainty

Directory of Open Access Journals (Sweden)

Seungbeom Kim

2017-01-01

Full Text Available To optimize the firm’s profit during a finite planning horizon, a dynamic programming model is used to make joint pricing and inventory replenishment decision assuming that customers are loss averse and the firm is risk averse. We model the loss averse customer’s demand using the multinomial choice model. In this choice model, we consider the acquisition and transition utilities widely used by a mental accounting theory which also incorporate the reference price and actual price. Then, we show that there is an optimal inventory policy which is base-stock policy depending on the accumulated wealth in each period.

Visual Aversive Learning Compromises Sensory Discrimination.

Science.gov (United States)

Shalev, Lee; Paz, Rony; Avidan, Galia

2018-03-14

Aversive learning is thought to modulate perceptual thresholds, which can lead to overgeneralization. However, it remains undetermined whether this modulation is domain specific or a general effect. Moreover, despite the unique role of the visual modality in human perception, it is unclear whether this aspect of aversive learning exists in this modality. The current study was designed to examine the effect of visual aversive outcomes on the perception of basic visual and auditory features. We tested the ability of healthy participants, both males and females, to discriminate between neutral stimuli, before and after visual learning. In each experiment, neutral stimuli were associated with aversive images in an experimental group and with neutral images in a control group. Participants demonstrated a deterioration in discrimination (higher discrimination thresholds) only after aversive learning. This deterioration was measured for both auditory (tone frequency) and visual (orientation and contrast) features. The effect was replicated in five different experiments and lasted for at least 24 h. fMRI neural responses and pupil size were also measured during learning. We showed an increase in neural activations in the anterior cingulate cortex, insula, and amygdala during aversive compared with neutral learning. Interestingly, the early visual cortex showed increased brain activity during aversive compared with neutral context trials, with identical visual information. Our findings imply the existence of a central multimodal mechanism, which modulates early perceptual properties, following exposure to negative situations. Such a mechanism could contribute to abnormal responses that underlie anxiety states, even in new and safe environments. SIGNIFICANCE STATEMENT Using a visual aversive-learning paradigm, we found deteriorated discrimination abilities for visual and auditory stimuli that were associated with visual aversive stimuli. We showed increased neural

The effect of accountability on loss aversion.

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Vieider, Ferdinand M

2009-09-01

This paper investigates the effect of accountability-the expectation on the side of the decision maker of having to justify his/her decisions to somebody else-on loss aversion. Loss aversion is commonly thought to be the strongest component of risk aversion. Accountability is found to reduce the bias of loss aversion. This effect is explained by the higher cognitive effort induced by accountability, which triggers a rational check on emotional reactions at the base of loss aversion, leading to a reduction of the latter. Connections to dual-processing models are discussed.

Aversive tension of adolescents with anorexia nervosa in daily course: a case-controlled and smartphone-based ambulatory monitoring trial.

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Kolar, David Raphael; Bürger, Arne; Hammerle, Florian; Jenetzky, Ekkehart

2014-04-23

Monitoring and reduction of aversive tension is a core issue in dialectical behaviour therapy of patients. It has been shown that aversive tension is increased in adult borderline personality disorder and is linked to low emotion labelling ability. However, until now there is no documented evidence that patients with anorexia nervosa suffer from aversive tension as well. Furthermore the usability of a smartphone application for ambulatory monitoring purposes has not been sufficiently explored. We compare the mean and maximum self-reported aversive tension in 20 female adolescents (12-19 years) with anorexia nervosa in outpatient treatment with 20 healthy controls. They are required to answer hourly, over a 2-day period, that is, about 30 times, four short questions on their smartphone, which ensures prompt documentation without any recall bias. At the close out, the participants give a structured usability feedback on the application and the procedure. The achieved result of this trial has direct relevance for efficient therapy strategies and is a prerequisite for trials regarding dialectical behaviour therapy in anorexia nervosa. The results will be disseminated through peer-review publications. The ethics committee of the regional medical association in Mainz, Germany approved the study protocol under the reference number 837.177.13. The trial is registered at the German clinical trials registration under the reference number DRKS00005228.

Peer effects in risk aversion.

Science.gov (United States)

Balsa, Ana I; Gandelman, Néstor; González, Nicolás

2015-01-01

We estimate peer effects in risk attitudes in a sample of high school students. Relative risk aversion is elicited from surveys administered at school. Identification of peer effects is based on parents not being able to choose the class within the school of their choice, and on the use of instrumental variables conditional on school-grade fixed effects. We find a significant and quantitatively large impact of peers' risk attitudes on a male individual's coefficient of risk aversion. Specifically, a one standard deviation increase in the group's coefficient of risk aversion increases an individual's risk aversion by 43%. Our findings shed light on the origin and stability of risk attitudes and, more generally, on the determinants of economic preferences. © 2014 Society for Risk Analysis.

Risk Aversion and Job Mobility

OpenAIRE

van Huizen, T.M.; Alessie, Rob

2016-01-01

Job mobility is inherently risky as workers have limited ex ante information about the quality of outside jobs. Using a large longitudinal Dutch dataset, which includes data on risk preferences elicited through (incentivized) experiments, we examine the relation between risk aversion and job mobility. The results for men show that risk averse workers are less likely to move to other jobs. For women, the evidence that risk aversion affects job mobility is weak. Our empirical findings indicate ...

Incidental fear cues increase monetary loss aversion.

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Schulreich, Stefan; Gerhardt, Holger; Heekeren, Hauke R

2016-04-01

In many everyday decisions, people exhibit loss aversion-a greater sensitivity to losses relative to gains of equal size. Loss aversion is thought to be (at least partly) mediated by emotional--in particular, fear-related--processes. Decision research has shown that even incidental emotions, which are unrelated to the decision at hand, can influence decision making. The effect of incidental fear on loss aversion, however, is thus far unclear. In two studies, we experimentally investigated how incidental fear cues, presented during (Study 1) or before (Study 2) choices to accept or reject mixed gambles over real monetary stakes, influence monetary loss aversion. We find that the presentation of fearful faces, relative to the presentation of neutral faces, increased risk aversion-an effect that could be attributed to increased loss aversion. The size of this effect was moderated by psychopathic personality: Fearless dominance, in particular its interpersonal facet, but not self-centered impulsivity, attenuated the effect of incidental fear cues on loss aversion, consistent with reduced fear reactivity. Together, these results highlight the sensitivity of loss aversion to the affective context. (c) 2016 APA, all rights reserved).

Unpleasant odors increase aversion to monetary losses.

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Stancak, Andrej; Xie, Yuxin; Fallon, Nicholas; Bulsing, Patricia; Giesbrecht, Timo; Thomas, Anna; Pantelous, Athanasios A

2015-04-01

Loss aversion is the tendency to prefer avoiding losses over acquiring gains of equal nominal values. Unpleasant odors not only influence affective state but have also been shown to activate brain regions similar to those mediating loss aversion. Therefore, we hypothesized a stronger loss aversion in a monetary gamble task if gambles were associated with an unpleasant as opposed to pleasant odor. In thirty human subjects, unpleasant (methylmercaptan), pleasant (jasmine), and neutral (clean air) odors were presented for 4 s. At the same time, uncertain gambles offering an equal chance of gain or loss of a variable amount of money, or a prospect of an assured win were displayed. One hundred different gambles were presented three times, each time paired with a different odor. Loss aversion, risk aversion, and logit sensitivity were evaluated using non-linear fitting of individual gamble decisions. Loss aversion was larger when prospects were displayed in the presence of methylmercaptan compared to jasmine or clean air. Moreover, individual differences in changes in loss aversion to the unpleasant as compared to pleasant odor correlated with odor pleasantness but not with odor intensity. Skin conductance responses to losses during the outcome period were larger when gambles were associated with methylmercaptan compared to jasmine. Increased loss aversion while perceiving an unpleasant odor suggests a dynamic adjustment of loss aversion toward greater sensitivity to losses. Given that odors are biological signals of hazards, such adjustment of loss aversion may have adaptive value in situations entailing threat or danger. Copyright © 2015 Elsevier B.V. All rights reserved.

Aversive racism in Spain: testing the theory

NARCIS (Netherlands)

Wojcieszak, M.

2015-01-01

This study applies the aversive racism framework to Spain and tests whether aversive racism depends on intergroup contact. Relying on a 3 (qualifications) by 3 (ethnicity) experiment, this study finds that aversive racism is especially pronounced against the Mexican job applicant, and emerges among

The origin of risk aversion.

Science.gov (United States)

Zhang, Ruixun; Brennan, Thomas J; Lo, Andrew W

2014-12-16

Risk aversion is one of the most basic assumptions of economic behavior, but few studies have addressed the question of where risk preferences come from and why they differ from one individual to the next. Here, we propose an evolutionary explanation for the origin of risk aversion. In the context of a simple binary-choice model, we show that risk aversion emerges by natural selection if reproductive risk is systematic (i.e., correlated across individuals in a given generation). In contrast, risk neutrality emerges if reproductive risk is idiosyncratic (i.e., uncorrelated across each given generation). More generally, our framework implies that the degree of risk aversion is determined by the stochastic nature of reproductive rates, and we show that different statistical properties lead to different utility functions. The simplicity and generality of our model suggest that these implications are primitive and cut across species, physiology, and genetic origins.

Alcohol reduces aversion to ambiguity

Directory of Open Access Journals (Sweden)

Tadeusz eTyszka

2015-01-01

Full Text Available Several years ago, Cohen, Dearnaley, and Hansel [1] demonstrated that under the influence of alcohol drivers became more risk prone, although their risk perception remained unchanged. Research shows that ambiguity aversion is to some extent positively correlated with risk aversion, though not very highly [2]. The question addressed by the present research is whether alcohol reduces ambiguity aversion. Our research was conducted in a natural setting (a restaurant bar, where customers with differing levels of alcohol intoxication were offered a choice between a risky and an ambiguous lottery. We found that alcohol reduced ambiguity aversion and that the effect occurred in men but not women. We interpret these findings in terms of the risk-as-value hypothesis, according to which, people in Western culture tend to value risk, and suggest that alcohol consumption triggers adherence to socially and culturally valued patterns of conduct different for men and women.

Alcohol reduces aversion to ambiguity.

Science.gov (United States)

Tyszka, Tadeusz; Macko, Anna; Stańczak, Maciej

2014-01-01

Several years ago, Cohen et al. (1958) demonstrated that under the influence of alcohol drivers became more risk prone, although their risk perception remained unchanged. Research shows that ambiguity aversion is to some extent positively correlated with risk aversion, though not very highly (Camerer and Weber, 1992). The question addressed by the present research is whether alcohol reduces ambiguity aversion. Our research was conducted in a natural setting (a restaurant bar), where customers with differing levels of alcohol intoxication were offered a choice between a risky and an ambiguous lottery. We found that alcohol reduced ambiguity aversion and that the effect occurred in men but not women. We interpret these findings in terms of the risk-as-value hypothesis, according to which, people in Western culture tend to value risk, and suggest that alcohol consumption triggers adherence to socially and culturally valued patterns of conduct different for men and women.

Small Stakes Risk Aversion in the Laboratory

DEFF Research Database (Denmark)

Harrison, Glenn W.; Lau, Morten I.; Ross, Don

2017-01-01

Evidence of risk aversion in laboratory settings over small stakes leads to a priori implausible levels of risk aversion over large stakes under certain assumptions. One core assumption in statements of this calibration puzzle is that small-stakes risk aversion is observed over all levels of wealth...

Risk aversion and social networks

NARCIS (Netherlands)

Kovářík, J.; van der Leij, M.J.

2014-01-01

This paper first investigates empirically the relationship between risk aversion and social network structure in a large group of undergraduate students. We find that risk aversion is strongly correlated to local network clustering, that is, the probability that one has a social tie to friends of

Loss aversion and rent-seeking: An experimental study

OpenAIRE

Kong, Xiaojing

2008-01-01

We report an experiment designed to evaluate the impact of loss aversion on rent-seeking contests. We find, as theoretically predicted, a negative relationship between rent-seeking expenditures and loss aversion. However, for any degree of loss aversion, levels of rent-seeking expenditure are higher than predicted. Moreover, we find that the effect of loss aversion becomes weaker with repetition of the contest.

Interactions between radiation and amphetamine in taste aversion learning and the role of the area postrema in amphetamine-induced conditioned taste aversions

International Nuclear Information System (INIS)

Rabin, B.M.; Hunt, W.A.; Lee, J.

1987-01-01

Three experiments were run to assess the role of the area postrema in taste aversion learning resulting from combined treatment with subthreshold unconditioned stimuli and in the acquisition of an amphetamine-induced taste aversion. In the first experiment, it was shown that combined treatment with subthreshold radiation (15 rad) and subthreshold amphetamine (0.5 mg/kg, IP) resulted in the acquisition of a taste aversion. The second experiment showed that lesions of the area postrema blocked taste aversion learning produced by two subthreshold doses of amphetamine. In the third experiment, which looked at the dose-response curve for amphetamine-induced taste aversion learning in intact rats and rats with area postrema lesions, it was shown that both groups of rats acquired taste aversions following injection of amphetamine, although the rats with lesions showed a less severe aversion than the intact rats. The results are interpreted as indicating that amphetamine-induced taste aversion learning may involve area postrema-mediated mechanisms, particularly at the lower doses, but that an intact area postrema is not a necessary condition for the acquisition of an amphetamine-induced taste aversion

Social influences on inequity aversion in children.

Directory of Open Access Journals (Sweden)

Katherine McAuliffe

Full Text Available Adults and children are willing to sacrifice personal gain to avoid both disadvantageous and advantageous inequity. These two forms of inequity aversion follow different developmental trajectories, with disadvantageous inequity aversion emerging around 4 years and advantageous inequity aversion emerging around 8 years. Although inequity aversion is assumed to be specific to situations where resources are distributed among individuals, the role of social context has not been tested in children. Here, we investigated the influence of two aspects of social context on inequity aversion in 4- to 9-year-old children: (1 the role of the experimenter distributing rewards and (2 the presence of a peer with whom rewards could be shared. Experiment 1 showed that children rejected inequity at the same rate, regardless of whether the experimenter had control over reward allocations. This indicates that children's decisions are based upon reward allocations between themselves and a peer and are not attempts to elicit more favorable distributions from the experimenter. Experiment 2 compared rejections of unequal reward allocations in children interacting with or without a peer partner. When faced with a disadvantageous distribution, children frequently rejected a smaller reward when a larger reward was visible, even if no partner would obtain the larger reward. This suggests that nonsocial factors partly explain disadvantageous inequity rejections. However, rejections of disadvantageous distributions were higher when the larger amount would go to a peer, indicating that social context enhances disadvantageous inequity aversion. By contrast, children rejected advantageous distributions almost exclusively in the social context. Therefore, advantageous inequity aversion appears to be genuinely social, highlighting its potential relevance for the development of fairness concerns. By comparing social and nonsocial factors, this study provides a detailed picture of

Heterogeneity of Loss Aversion in Pathological Gambling.

Science.gov (United States)

Takeuchi, Hideaki; Kawada, Ryosaku; Tsurumi, Kosuke; Yokoyama, Naoto; Takemura, Ariyoshi; Murao, Takuro; Murai, Toshiya; Takahashi, Hidehiko

2016-12-01

Pathological gambling (PG) is characterized by continual repeated gambling behavior despite negative consequences. PG is considered to be a disorder of altered decision-making under risk, and behavioral economics tools were utilized by studies on decision-making under risk. At the same time, PG was suggested to be a heterogeneous disorder in terms of personality traits as well as risk attitude. We aimed to examine the heterogeneity of PG in terms of loss aversion, which means that a loss is subjectively felt to be larger than the same amount of gain. Thirty-one male PG subjects and 26 male healthy control (HC) subjects underwent a behavioral economics task for estimation of loss aversion and personality traits assessment. Although loss aversion in PG subjects was not significantly different from that in HC subjects, distributions of loss aversion differed between PG and HC subjects. HC subjects were uniformly classified into three levels (low, middle, high) of loss aversion, whereas PG subjects were mostly classified into the two extremes, and few PG subjects were classified into the middle range. PG subjects with low and high loss aversion showed a significant difference in anxiety, excitement-seeking and craving intensity. Our study suggested that PG was a heterogeneous disorder in terms of loss aversion. This result might be useful for understanding cognitive and neurobiological mechanisms and the establishment of treatment strategies for PG.

Impact of childhood trauma and cognitive emotion regulation strategies on risk-aversive and loss-aversive patterns of decision-making in patients with depression.

Science.gov (United States)

Huh, Hyu Jung; Baek, Kwangyeol; Kwon, Jae-Hyung; Jeong, Jaeseung; Chae, Jeong-Ho

2016-11-01

Although poor decision-making ultimately impairs quality of life in depression, few studies describe the clinical characteristics of patients suffering from dysfunctional decision-making. This study aims to delineate the effect of childhood trauma and other personality factors on risk-aversive and loss-aversive patterns of decision-making in patients with depression. A total of 50 depressive patients completed surveys for the measurement of sociodemographic factors, trauma loads and other clinical characteristics, including depression, anxiety, and strategies for emotion regulation. Risk aversion and loss aversion were quantified using probability discounting task and a 50:50 gamble on monetary decision-making task under specified risks. Stepwise multiple regression analysis was performed to determine the factors, predicting risk aversion or loss aversion in depression. Childhood trauma was the most prominent factor predicting loss aversion in patients with depressive disorders. Overall maladaptive emotion regulation strategies were associated with risk aversion. Childhood trauma and specific strategies of emotion regulation contribute to risk or loss aversion in patients with depression. These findings may provide useful insight into elaborative evaluation and interventions to improve decision-making and quality of life in patients with depression.

Deciding for Future Selves Reduces Loss Aversion

Directory of Open Access Journals (Sweden)

Qiqi Cheng

2017-09-01

Full Text Available In this paper, we present an incentivized experiment to investigate the degree of loss aversion when people make decisions for their current selves and future selves under risk. We find that when participants make decisions for their future selves, they are less loss averse compared to when they make decisions for their current selves. This finding is consistent with the interpretation of loss aversion as a bias in decision-making driven by emotions, which are reduced when making decisions for future selves. Our findings endorsed the external validity of previous studies on the impact of emotion on loss aversion in a real world decision-making environment.

Deciding for Future Selves Reduces Loss Aversion.

Science.gov (United States)

Cheng, Qiqi; He, Guibing

2017-01-01

In this paper, we present an incentivized experiment to investigate the degree of loss aversion when people make decisions for their current selves and future selves under risk. We find that when participants make decisions for their future selves, they are less loss averse compared to when they make decisions for their current selves. This finding is consistent with the interpretation of loss aversion as a bias in decision-making driven by emotions, which are reduced when making decisions for future selves. Our findings endorsed the external validity of previous studies on the impact of emotion on loss aversion in a real world decision-making environment.

Aversion substance(s) of the rat coagulating glands

Science.gov (United States)

Gawienowski, Anthony M.; Berry, Iver J.; Kennelly, James J.

1982-01-01

The aversive substance(s) present in adult male urine were not found in castrate rat urine. Removal of the coagulating glands also resulted in a loss of the aversion compounds. The aversion substances were restored to the urine after androgen treatment of the castrate rats.

Aversive Learning and Trait Aggression Influence Retaliatory Behavior.

Science.gov (United States)

Molapour, Tanaz; Lindström, Björn; Olsson, Andreas

2016-01-01

In two experiments (n = 35, n = 34), we used a modified fear-conditioning paradigm to investigate the role of aversive learning in retaliatory behavior in social context. Participants first completed an initial aversive learning phase in which the pairing of a neutral conditioned stimulus (CS; i.e., neutral face) with a naturally aversive unconditioned stimulus (US; electric shock) was learned. Then they were given an opportunity to interact (i.e., administer 0-2 shocks) with the same faces again, during a Test phase. In Experiment 2, we used the same paradigm with the addition of online trial-by-trial ratings (e.g., US expectancy and anger) to examine the role of aversive learning, anger, and the learned expectancy of receiving punishment more closely. Our results indicate that learned aversions influenced future retaliation in a social context. In both experiments, participants showed largest skin conductance responses (SCRs) to the faces paired with one or two shocks, demonstrating successful aversive learning. Importantly, participants administered more shocks to the faces paired with the most number of shocks when the opportunity was given during test. Also, our results revealed that aggressive traits (Buss and Perry Aggression scale) were associated with retaliation only toward CSs associated with aversive experiences. These two experiments show that aggressive traits, when paired with aversive learning experiences enhance the likelihood to act anti-socially toward others.

An Aversion-Desensitization Treatment for Alcoholism

Science.gov (United States)

Primo, Richard V.; And Others

1972-01-01

A six-to nine-month interview follow-up showed that five of the seven traceable Ss given the interpersonal aversion-systematic desensitization treatment had been abstinent, compared with only one of seven treated by the interpersonal aversion-control procedure. (Author)

Are Teams Less Inequality Averse than Individuals?

OpenAIRE

He, Haoran; Villeval, Marie Claire

2014-01-01

We compare inequality aversion in individuals and teams by means of both within- and between-subject experimental designs, and we investigate how teams aggregate individual preferences. We find that team decisions reveal less inequality aversion than individual initial proposals in team decision-making. However, teams are no more selfish than individuals who decide in isolation. Individuals express strategically more inequality aversion in their initial proposals in team decision-making becau...

Chronic nailbiting: a controlled comparison of competing response and mild aversion treatments.

Science.gov (United States)

Allen, K W

1996-03-01

Recent studies have suggested that competing response, an abridged version of Azrin and Nunn's (1973) habit reversal method (Behaviour Research and Therapy, 11, 619-628), is a key component in the treatment of chronic nailbiting (Horne & Wilkinson, 1980, Behaviour Research and Therapy, 18, 287-291; Silber & Haynes, 1992, Behaviour Research and Therapy, 30, 15-22). This study replicated and extended the latter by adding an 8 week follow-up period and by using a non-student sample. Forty-five chronic nailbiter Ss were divided into three experimental groups. One method involved the use of mild aversion in which Ss painted a bitter substance on their nails. A second method required the subject to perform a competing response whenever they had the urge to nailbite or found themselves biting their nails. Both methods included self-monitoring of the behaviour and a third group of Ss performed self-monitoring alone as a control condition. The study lasted 12 weeks. Mild aversion resulted in significant improvements in nail length, with the competing response method just failing to show significance in this regard. There was no significant improvement for the control group. The implications for further study and the benefits of competing response in the light of these findings are discussed in terms of treatment success and use of therapist time.

Multiattribute Utility Theory, Intertemporal Utility and Correlation Aversion

DEFF Research Database (Denmark)

Andersen, Steffen; Harrison, Glenn W.; Lau, Morten

2018-01-01

Convenient assumptions about qualitative properties of the intertemporal utility function have generated counterintuitive implications for the relationship between atemporal risk aversion and the intertemporal elasticity of substitution. If the intertemporal utility function is additively separable...... aversion. Our results show that subjects are correlation averse over lotteries with intertemporal income profiles....

How to Make Loss Aversion Disappear and Reverse: Tests of the Decision by Sampling Origin of Loss Aversion

OpenAIRE

Walasek, Lukasz; Stewart, Neil

2014-01-01

One of the most robust empirical findings in the behavioral sciences is loss aversion—the finding that losses loom larger than gains. We offer a new psychological explanation of the origins of loss aversion in which loss aversion emerges from differences in the distribution of gains and losses people experience. In 4 experiments, we tested this proposition by manipulating the range of gains and losses that individuals saw during the process of eliciting their loss aversion. We were able to fi...

Reference-dependent preferences and loss aversion

Directory of Open Access Journals (Sweden)

Einat Neuman

2008-02-01

Full Text Available This study employs a Discrete Choice Experiment (DCE in the health-care sector to test the loss aversion theory that is derived from reference-dependent preferences: The absolute subjective value of a deviation from a reference point is generally greater when the deviation represents a loss than when the same-sized change is perceived as a gain. As far as is known, this paper is the first to use a DCE to test the loss aversion theory. A DCE is a highly suitable tool for such testing because it estimates the marginal valuations of attributes, based onextit{ deviations from a reference point} (a constant scenario. Moreover, loss aversion can be examined for extit{each attribute separately}. Another advantage of a DCE is that is can be applied toextit{ non-traded goods with non-tangible attributes}. A health-care event is used for empirical illustration: The loss aversion theory is tested within the context of preference structures for maternity-ward attributes, estimated using data gathered from 3850 observations made by a sample of 542 women who had recently given birth. Seven hypotheses are presented and tested. Overall, significant support for behavioral loss aversion theories was found. %JEL codes: D01, D12, I19

Coping with Loss Aversion in the Newsvendor Model

Directory of Open Access Journals (Sweden)

Jianwu Sun

2015-01-01

Full Text Available We introduce loss aversion into the decision framework of the newsvendor model. By introducing the loss aversion coefficient λ, we propose a novel utility function for the loss-averse newsvendor. First, we obtain the optimal order quantity to maximize the expected utility for the loss-averse newsvendor who is risk-neutral. It is found that this optimal order quantity is smaller than the expected profit maximization order quantity in the classical newsvendor model, which may help to explain the decision bias in the classical newsvendor model. Then, to reduce the risk which originates from the fluctuation in the market demand, we achieve the optimal order quantity to maximize CVaR about utility for the loss-averse newsvendor who is risk-averse. We find that this optimal order quantity is smaller than the optimal order quantity to maximize the expected utility above and is decreasing in the confidence level α. Further, it is proved that the expected utility under this optimal order quantity is decreasing in the confidence level α, which verifies that low risk implies low return. Finally, a numerical example is given to illustrate the obtained results and some management insights are suggested for the loss-averse newsvendor model.

Amygdala damage eliminates monetary loss aversion.

Science.gov (United States)

De Martino, Benedetto; Camerer, Colin F; Adolphs, Ralph

2010-02-23

Losses are a possibility in many risky decisions, and organisms have evolved mechanisms to evaluate and avoid them. Laboratory and field evidence suggests that people often avoid risks with losses even when they might earn a substantially larger gain, a behavioral preference termed "loss aversion." The cautionary brake on behavior known to rely on the amygdala is a plausible candidate mechanism for loss aversion, yet evidence for this idea has so far not been found. We studied two rare individuals with focal bilateral amygdala lesions using a series of experimental economics tasks. To measure individual sensitivity to financial losses we asked participants to play a variety of monetary gambles with possible gains and losses. Although both participants retained a normal ability to respond to changes in the gambles' expected value and risk, they showed a dramatic reduction in loss aversion compared to matched controls. The findings suggest that the amygdala plays a key role in generating loss aversion by inhibiting actions with potentially deleterious outcomes.

Narrative Aversion: Challenges for the Illness Narrative Advocate.

Science.gov (United States)

Behrendt, Kathy

2017-02-01

Engaging in self-narrative is often touted as a powerful antidote to the bad effects of illness. However, there are various examples of what may broadly be termed "aversion" to illness narrative. I group these into three kinds: aversion to certain types of illness narrative; aversion to illness narrative as a whole; and aversion to illness narrative as an essentially therapeutic endeavor. These aversions can throw into doubt the advantages claimed for the illness narrator, including the key benefits of repair to the damage illness does to identity and life-trajectory. Underlying these alleged benefits are two key presuppositions: that it is the whole of one's life that is narratively unified, and that one's identity is inextricably bound up with narrative. By letting go of these assumptions, illness narrative advocates can respond to the challenges of narrative aversions. © The Author 2016. Published by Oxford University Press, on behalf of The Journal of Medicine and Philosophy Inc. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Rethinking a Negative Event: The Affective Impact of Ruminative versus Imagery-Based Processing of Aversive Autobiographical Memories.

Science.gov (United States)

Slofstra, Christien; Eisma, Maarten C; Holmes, Emily A; Bockting, Claudi L H; Nauta, Maaike H

2017-01-01

aversive autobiographical memories serves to avoid the negative emotions evoked by such memories. Furthermore, findings suggest that depressive symptomatology is associated with the spontaneous use and the affective impact of processing modes during recall of aversive autobiographical memories. Clinical studies are needed that examine the role of processing modes during aversive autobiographical memory recall in depression, including the potential effectiveness of targeting processing modes in therapy.

Inequality Aversion and Voting on Redistribution

DEFF Research Database (Denmark)

Höchtl, Wolfgang; Sausgruber, Rupert; Tyran, Jean-Robert

of income classes. We experimentally study voting on redistribution between two income classes and show that the effect of inequality aversion is asymmetric. Inequality aversion is more likely to matter if the “rich” are in majority. With a “poor” majority, we find that redistribution outcomes look...

Inequality aversion and voting on redistribution

DEFF Research Database (Denmark)

Höchtl, Wolfgang; Sausgruber, Rupert; Tyran, Jean-Robert Karl

2012-01-01

of income classes. We experimentally study voting on redistribution between two income classes and show that the effect of inequality aversion is asymmetric. Inequality aversion is more likely to matter if the “rich” are in majority. With a “poor” majority, we find that redistribution outcomes look...

Brief Report: Risk-Aversion and Rationality in Autism Spectrum Disorders.

Science.gov (United States)

Gosling, Corentin J; Moutier, Sylvain

2018-05-30

Risk-aversion and rationality have both been highlighted as core features of decision making in individuals with Autism Spectrum Disorders (ASD). This study tested whether risk-aversion is related to rational decision-making in ASD individuals. ASD and matched control adults completed a decision-making task that discriminated between the use of risk-averse and rational strategies. Results showed that overall, ASD participants were more risk-averse than control participants. Specifically, both groups made similar choices when risk-aversion was the less rational strategy but ASD participants chose more rational options than control participants when risk-aversion was the most rational strategy. This study confirmed that risk-aversion is a core feature of ASD and revealed that ASD individuals can switch their decision-making strategy adaptively to avoid negative consequences.

Schizophrenia illness severity is associated with reduced loss aversion.

Science.gov (United States)

Currie, James; Buruju, Dheeraj; Perrin, Jennifer S; Reid, Ian C; Steele, J Douglas; Feltovich, Nick

2017-06-01

Loss aversion, whereby losses weigh more heavily than equal-sized gains, has been demonstrated in many decision-making settings. Previous research has suggested reduced loss aversion in schizophrenia, but with little evidence of a link between loss aversion and schizophrenia illness severity. In this study, 20 individuals with schizophrenia and 16 control participants, matched by age and sex, played two versions of the Iterated Prisoners' Dilemma, one version with only positive payoffs and another version in which negative payoffs were possible, with the second version being derived from the first by subtracting a constant value from all payoffs. The control group demonstrated significantly lower cooperation rates under negative payoffs, compared with the version with only positive payoffs, indicative of loss aversion. The patient group on average showed no loss aversion response. Moreover, the extent of loss aversion in patients was found to be negatively correlated with schizophrenia illness severity, with less ill patients showing loss aversion more similar to controls. Results were found to be robust to the inclusion of potential confounding factors as covariates within rigorous probit regression analyses. Reduced loss aversion is a feature of schizophrenia and related to illness severity. Copyright © 2017. Published by Elsevier B.V.

Mechanisms of radiation-induced conditioned taste aversion learning

International Nuclear Information System (INIS)

Rabin, B.M.; Hunt, W.A.

1986-01-01

The literature on taste aversion learning is reviewed and discussed, with particular emphasis on those studies that have used exposure to ionizing radiation as an unconditioned stimulus to produce a conditioned taste aversion. The primary aim of the review is to attempt to define the mechanisms that lead to the initiation of the taste aversion response following exposure to ionizing radiation. Studies using drug treatments to produce a taste aversion have been included to the extent that they are relevant to understanding the mechanisms by which exposure to ionizing radiation can affect the behavior of the organism. 141 references

Risk aversion and compliance in markets for pollution control.

Science.gov (United States)

Stranlund, John K

2008-07-01

This paper examines the effects of risk aversion on compliance choices in markets for pollution control. A firm's decision to be compliant or not is independent of its manager's risk preference. However, non-compliant firms with risk-averse managers will have lower violations than otherwise identical firms with risk-neutral managers. The violations of non-compliant firms with risk-averse managers are independent of differences in their profit functions and their initial allocations of permits if and only if their managers' utility functions exhibit constant absolute risk aversion. However, firm-level characteristics do impact violation choices when managers have coefficients of absolute risk aversion that are increasing or decreasing in profit levels. Finally, in the equilibrium of a market for emissions rights with widespread non-compliance, risk aversion is associated with higher permit prices, better environmental quality, and lower aggregate violations.

Time-varying risk aversion. An application to energy hedging

Energy Technology Data Exchange (ETDEWEB)

Cotter, John [Centre for Financial Markets, School of Business, University College Dublin, Blackrock, Co. Dublin (Ireland); Hanly, Jim [School of Accounting and Finance, Dublin Institute of Technology, Dublin 2 (Ireland)

2010-03-15

Risk aversion is a key element of utility maximizing hedge strategies; however, it has typically been assigned an arbitrary value in the literature. This paper instead applies a GARCH-in-Mean (GARCH-M) model to estimate a time-varying measure of risk aversion that is based on the observed risk preferences of energy hedging market participants. The resulting estimates are applied to derive explicit risk aversion based optimal hedge strategies for both short and long hedgers. Out-of-sample results are also presented based on a unique approach that allows us to forecast risk aversion, thereby estimating hedge strategies that address the potential future needs of energy hedgers. We find that the risk aversion based hedges differ significantly from simpler OLS hedges. When implemented in-sample, risk aversion hedges for short hedgers outperform the OLS hedge ratio in a utility based comparison. (author)

Time-varying risk aversion. An application to energy hedging

International Nuclear Information System (INIS)

Cotter, John; Hanly, Jim

2010-01-01

Risk aversion is a key element of utility maximizing hedge strategies; however, it has typically been assigned an arbitrary value in the literature. This paper instead applies a GARCH-in-Mean (GARCH-M) model to estimate a time-varying measure of risk aversion that is based on the observed risk preferences of energy hedging market participants. The resulting estimates are applied to derive explicit risk aversion based optimal hedge strategies for both short and long hedgers. Out-of-sample results are also presented based on a unique approach that allows us to forecast risk aversion, thereby estimating hedge strategies that address the potential future needs of energy hedgers. We find that the risk aversion based hedges differ significantly from simpler OLS hedges. When implemented in-sample, risk aversion hedges for short hedgers outperform the OLS hedge ratio in a utility based comparison. (author)

Acceptable losses: the debatable origins of loss aversion.

Science.gov (United States)

Yechiam, Eldad

2018-04-16

It is often claimed that negative events carry a larger weight than positive events. Loss aversion is the manifestation of this argument in monetary outcomes. In this review, we examine early studies of the utility function of gains and losses, and in particular the original evidence for loss aversion reported by Kahneman and Tversky (Econometrica  47:263-291, 1979). We suggest that loss aversion proponents have over-interpreted these findings. Specifically, the early studies of utility functions have shown that while very large losses are overweighted, smaller losses are often not. In addition, the findings of some of these studies have been systematically misrepresented to reflect loss aversion, though they did not find it. These findings shed light both on the inability of modern studies to reproduce loss aversion as well as a second literature arguing strongly for it.

Risk Aversion Relates to Cognitive Ability

DEFF Research Database (Denmark)

Andersson, Ola; Holm, Håkan J.; Tyran, Jean-Robert Karl

2016-01-01

Recent experimental studies suggest that risk aversion is negatively related to cognitive ability. In this paper we report evidence that this relation might be spurious. We recruit a large subject pool drawn from the general Danish population for our experiment. By presenting subjects with choice...... tasks that vary the bias induced by random choices, we are able to generate both negative and positive correlations between risk aversion and cognitive ability. Structural estimation allowing for heterogeneity of noise yields no significant relation between risk aversion and cognitive ability. Our...... results suggest that cognitive ability is related to random decision making, rather than to risk preferences....

Risk aversion relates to cognitive ability

DEFF Research Database (Denmark)

Andersson, Ola; Holm, Håkan J.; Tyran, Jean-Robert Karl

Recent experimental studies suggest that risk aversion is negatively related to cognitive ability. In this paper we report evidence that this relation might be spurious. We recruit a large subject pool drawn from the general Danish population for our experiment. By presenting subjects with choice...... tasks that vary the bias induced by random choices, we are able to generate both negative and positive correlations between risk aversion and cognitive ability. Structural estimation allowing for heterogeneity of noise yields no significant relation between risk aversion and cognitive ability. Our...... results suggest that cognitive ability is related to random decision making rather than to risk preferences....

Chemosensory alterations and cancer therapies

International Nuclear Information System (INIS)

Bartoshuk, L.M.

1990-01-01

Taste and olfaction provide sensory information and sensory pleasure. Cancer therapies affect both. Chemotherapy has not been shown to produce dramatic losses of taste or smell, but systematic studies on various chemotherapeutic agents and types of cancer are lacking. Radiation therapy does produce clear losses of both taste and smell. Both chemotherapy and radiation therapy alter the pleasure produced by taste and smell through the formation of conditioned aversions. That is, foods consumed in proximity with the nausea of therapy come to be unpleasant. The impact of conditioned aversions can be diminished by providing a scapegoat food just before therapy. Alterations in foods may be beneficial to the cancer patient. Increasing the concentrations of flavor ingredients can compensate for sensory losses, and providing pureed foods that retain the cognitive integrity of a meal can benefit the patient who has chewing or swallowing problems

Ambiguity aversion in rhesus macaques

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Benjamin eHayden

2010-09-01

Full Text Available People generally prefer risky options, which have fully specified outcome probabilities, to ambiguous options, which have unspecified probabilities. This preference, formalized in economics, is strong enough that people will reliably prefer a risky option to an ambiguous option with a greater expected value. Explanations for ambiguity aversion often invoke uniquely human faculties like language, self-justification, or a desire to avoid public embarrassment. Challenging these ideas, here we demonstrate that a preference for unambiguous options is shared with rhesus macaques. We trained four monkeys to choose between pairs of options that both offered explicitly cued probabilities of large and small juice outcomes. We then introduced occasional trials where one of the options was obscured and examined their resulting preferences; we ran humans in a parallel experiment on a nearly identical task. We found that monkeys reliably preferred risky options to ambiguous ones, even when this bias was costly, closely matching the behavior of humans in the analogous task. Notably, ambiguity aversion varied parametrically with the extent of ambiguity. As expected, ambiguity aversion gradually declined as monkeys learned the underlying probability distribution of rewards. These data indicate that ambiguity aversion reflects fundamental cognitive biases shared with other animals rather than uniquely human factors guiding decisions.

How does economic risk aversion affect biodiversity?

Science.gov (United States)

Mouysset, L; Doyen, L; Jiguet, F

2013-01-01

Significant decline of biodiversity in farmlands has been reported for several decades. To limit the negative impact of agriculture, many agro-environmental schemes have been implemented, but their effectiveness remains controversial. In this context, the study of economic drivers is helpful to understand the role played by farming on biodiversity. The present paper analyzes the impact of risk aversion on farmland biodiversity. Here "risk aversion" means a cautious behavior of farmers facing uncertainty. We develop a bio-economic model that articulates bird community dynamics and representative farmers selecting land uses within an uncertain macro-economic context. It is specialized and calibrated at a regional scale for France through national databases. The influence of risk aversion is assessed on ecological, agricultural, and economic outputs through projections at the 2050 horizon. A high enough risk aversion appears sufficient to both manage economic risk and promote ecological performance. This occurs through a diversification mechanism on regional land uses. However, economic calibration leads to a weak risk-aversion parameter, which is consistent with the current decline of farmland birds. Spatial disparities however suggest that public incentives could be necessary to reinforce the diversification and bio-economic effectiveness.

Probabilistic Sophistication, Second Order Stochastic Dominance, and Uncertainty Aversion

OpenAIRE

Simone Cerreia-Vioglio; Fabio Maccheroni; Massimo Marinacci; Luigi Montrucchio

2010-01-01

We study the interplay of probabilistic sophistication, second order stochastic dominance, and uncertainty aversion, three fundamental notions in choice under uncertainty. In particular, our main result, Theorem 2, characterizes uncertainty averse preferences that satisfy second order stochastic dominance, as well as uncertainty averse preferences that are probabilistically sophisticated.

Small Stakes Risk Aversion in the Laboratory

DEFF Research Database (Denmark)

Harrison, Glenn W.; Lau, Morten; Ross, Don

Evidence of risk aversion in laboratory settings over small stakes leads to a priori implausible levels of risk aversion over large stakes under certain assumptions. One core assumption in standard statements of this calibration puzzle is that individuals define utility over terminal wealth......, and that terminal wealth is defined as the sum of extra-lab wealth and any wealth accumulated in the lab. This assumption is often used in Expected Utility Theory, as well as popular alternatives such as RankDependent Utility theory. Another core assumption is that the small-stakes risk aversion is observed over...... all levels of wealth, or over a “sufficiently large” range of wealth. Although this second assumption if often viewed as self-evident from the vast experimental literature showing risk aversion over laboratory stakes, it actually requires that lab wealth be varied for a given subject as one takes...

Risk aversion in medical decision making: a survey

OpenAIRE

Liliana Chicaíza; Mario García; Giancarlo Romano

2011-01-01

This article surveys the literature on risk aversion in medical decision making. The search covered Econlit, Jstor Science Direct and Springer Link since 1985. The results are classified in three topics: Risk aversion in the frameworks of Expected Utility and Rank Dependent Expected Utility theories, and the methodologies for measuring risk aversion and its applications to clinical situations from the points of view of economics and psychology. It was found that, despite conceptual and method...

Rethinking a Negative Event: The Affective Impact of Ruminative versus Imagery-Based Processing of Aversive Autobiographical Memories

Directory of Open Access Journals (Sweden)

Christien Slofstra

2017-05-01

on the hypothesis that ruminative processing of aversive autobiographical memories serves to avoid the negative emotions evoked by such memories. Furthermore, findings suggest that depressive symptomatology is associated with the spontaneous use and the affective impact of processing modes during recall of aversive autobiographical memories. Clinical studies are needed that examine the role of processing modes during aversive autobiographical memory recall in depression, including the potential effectiveness of targeting processing modes in therapy.

Risk Aversion, Price Uncertainty and Irreversible Investments

NARCIS (Netherlands)

van den Goorbergh, R.W.J.; Huisman, K.J.M.; Kort, P.M.

2003-01-01

This paper generalizes the theory of irreversible investment under uncertainty by allowing for risk averse investors in the absence of com-plete markets.Until now this theory has only been developed in the cases of risk neutrality, or risk aversion in combination with complete markets.Within a

Sodium butyrate into the insular cortex during conditioned taste-aversion acquisition delays aversive taste memory extinction.

Science.gov (United States)

Núñez-Jaramillo, Luis; Reyes-López, Julian; Miranda, María Isabel

2014-04-16

Histone acetylation is one mechanism that promotes gene expression, and it increases during learning of various tasks. Specifically, novel taste consumption produces an increased acetylation of histone lysine residues in the insular cortex (IC), where protein synthesis is crucial during memory consolidation of conditioned taste aversion (CTA). However, the role of this elevated histone acetylation during CTA learning has not been examined directly. Thus, the present study investigated the effects of sodium butyrate (NaBu), a histone deacetylase inhibitor, injected into the IC during CTA acquisition. Male Wistar rats, IC bilaterally implanted, were injected 60 min before saccharine presentation, with a total volume of 0.5 µl of NaBu solution (100, 500, and 10 µg/0.5 µl) or saline; 30 min later animals were injected intraperitoneally with lithium chloride, a malaise-inducing drug. The next day, CTA retrieval was tested. No effects of NaBu were observed during acquisition or retrieval, but during extinction trials, a significant delay in aversive memory extinction was observed in the group injected with the lowest NaBu dose. This result indicates that NaBu in the IC strengthens CTA and delays aversive memory extinction, and suggests that histone acetylation could increase long-term taste-aversive memory strength.

Repeatable aversion across threat types is linked with life-history traits but is dependent on how aversion is measured.

Science.gov (United States)

Davidson, Gabrielle L; Reichert, Michael S; Crane, Jodie M S; O'Shea, William; Quinn, John L

2018-02-01

Personality research suggests that individual differences in risk aversion may be explained by links with life-history variation. However, few empirical studies examine whether repeatable differences in risk avoidance behaviour covary with life-history traits among individuals in natural populations, or how these links vary depending on the context and the way risk aversion is measured. We measured two different risk avoidance behaviours (latency to enter the nest and inspection time) in wild great tits ( Parus major ) in two different contexts-response to a novel object and to a predator cue placed at the nest-box during incubation---and related these behaviours to female reproductive success and condition. Females responded equally strongly to both stimuli, and although both behaviours were repeatable, they did not correlate. Latency to enter was negatively related to body condition and the number of offspring fledged. By contrast, inspection time was directly explained by whether incubating females had been flushed from the nest before the trial began. Thus, our inferences on the relationship between risk aversion and fitness depend on how risk aversion was measured. Our results highlight the limitations of drawing conclusions about the relevance of single measures of a personality trait such as risk aversion.

Interoceptive ability predicts aversion to losses.

Science.gov (United States)

Sokol-Hessner, Peter; Hartley, Catherine A; Hamilton, Jeffrey R; Phelps, Elizabeth A

2015-01-01

Emotions have been proposed to inform risky decision-making through the influence of affective physiological responses on subjective value. The ability to perceive internal body states, or "interoception" may influence this relationship. Here, we examined whether interoception predicts participants' degree of loss aversion, which has been previously linked to choice-related arousal responses. Participants performed both a heartbeat-detection task indexing interoception and a risky monetary decision-making task, from which loss aversion, risk attitudes and choice consistency were parametrically measured. Interoceptive ability correlated selectively with loss aversion and was unrelated to the other value parameters. This finding suggests that specific and separable component processes underlying valuation are shaped not only by our physiological responses, as shown in previous findings, but also by our interoceptive access to such signals.

Effective return, risk aversion and drawdowns

Science.gov (United States)

Dacorogna, Michel M.; Gençay, Ramazan; Müller, Ulrich A.; Pictet, Olivier V.

2001-01-01

We derive two risk-adjusted performance measures for investors with risk averse preferences. Maximizing these measures is equivalent to maximizing the expected utility of an investor. The first measure, Xeff, is derived assuming a constant risk aversion while the second measure, Reff, is based on a stronger risk aversion to clustering of losses than of gains. The clustering of returns is captured through a multi-horizon framework. The empirical properties of Xeff, Reff are studied within the context of real-time trading models for foreign exchange rates and their properties are compared to those of more traditional measures like the annualized return, the Sharpe Ratio and the maximum drawdown. Our measures are shown to be more robust against clustering of losses and have the ability to fully characterize the dynamic behaviour of investment strategies.

Risk Aversion and Engagement in the Sharing Economy

Directory of Open Access Journals (Sweden)

Jessica Santana

2015-10-01

Full Text Available The sharing economy is a new online community that has important implications for offline behavior. This study evaluates whether engagement in the sharing economy is associated with an actor’s aversion to risk. Using a web-based survey and a field experiment, we apply an adaptation of Holt and Laury’s (2002 risk lottery game to a representative sample of sharing economy participants. We find that frequency of activity in the sharing economy predicts risk aversion, but only in interaction with satisfaction. While greater satisfaction with sharing economy websites is associated with a decrease in risk aversion, greater frequency of usage is associated with greater risk aversion. This analysis shows the limitations of a static perspective on how risk attitudes relate to participation in the sharing economy.

Empirical analysis of time preferences and risk aversion

NARCIS (Netherlands)

Tu, Q.

2005-01-01

One of the important contributions is that a structural model with the reference point and loss aversion for intertemporal choice was developed to estimate the coefficient of loss aversion and the reference points of individuals.

Differences in Risk Aversion between Young and Older Adults.

Science.gov (United States)

Albert, Steven M; Duffy, John

2012-01-15

Research on decision-making strategies among younger and older adults suggests that older adults may be more risk averse than younger people in the case of potential losses. These results mostly come from experimental studies involving gambling paradigms. Since these paradigms involve substantial demands on memory and learning, differences in risk aversion or other features of decision-making attributed to age may in fact reflect age-related declines in cognitive abilities. In the current study, older and younger adults completed a simpler, paired lottery choice task used in the experimental economics literature to elicit risk aversion. A similar approach was used to elicit participants' discount rates. The older adult group was more risk averse than younger adults (p Risk aversion and implied discount rates were weakly correlated. It may be valuable to investigate developmental changes in neural correlates of decision-making across the lifespan.

Ambiguity aversion and household portfolio choice puzzles: Empirical evidence*

Science.gov (United States)

Dimmock, Stephen G.; Kouwenberg, Roy; Mitchell, Olivia S.; Peijnenburg, Kim

2017-01-01

We test the relation between ambiguity aversion and five household portfolio choice puzzles: nonparticipation in equities, low allocations to equity, home-bias, own-company stock ownership, and portfolio under-diversification. In a representative US household survey, we measure ambiguity preferences using custom-designed questions based on Ellsberg urns. As theory predicts, ambiguity aversion is negatively associated with stock market participation, the fraction of financial assets in stocks, and foreign stock ownership, but it is positively related to own-company stock ownership. Conditional on stock ownership, ambiguity aversion is related to portfolio under-diversification, and during the financial crisis, ambiguity-averse respondents were more likely to sell stocks. PMID:28458446

Ambiguity aversion and household portfolio choice puzzles: Empirical evidence.

Science.gov (United States)

Dimmock, Stephen G; Kouwenberg, Roy; Mitchell, Olivia S; Peijnenburg, Kim

2016-03-01

We test the relation between ambiguity aversion and five household portfolio choice puzzles: nonparticipation in equities, low allocations to equity, home-bias, own-company stock ownership, and portfolio under-diversification. In a representative US household survey, we measure ambiguity preferences using custom-designed questions based on Ellsberg urns. As theory predicts, ambiguity aversion is negatively associated with stock market participation, the fraction of financial assets in stocks, and foreign stock ownership, but it is positively related to own-company stock ownership. Conditional on stock ownership, ambiguity aversion is related to portfolio under-diversification, and during the financial crisis, ambiguity-averse respondents were more likely to sell stocks.

A Moist Crevice for Word Aversion: In Semantics Not Sounds.

Directory of Open Access Journals (Sweden)

Paul H Thibodeau

Full Text Available Why do people self-report an aversion to words like "moist"? The present studies represent an initial scientific exploration into the phenomenon of word aversion by investigating its prevalence and cause. Results of five experiments indicate that about 10-20% of the population is averse to the word "moist." This population often speculates that phonological properties of the word are the cause of their displeasure. However, data from the current studies point to semantic features of the word-namely, associations with disgusting bodily functions-as a more prominent source of peoples' unpleasant experience. "Moist," for averse participants, was notable for its valence and personal use, rather than imagery or arousal-a finding that was confirmed by an experiment designed to induce an aversion to the word. Analyses of individual difference measures suggest that word aversion is more prevalent among younger, more educated, and more neurotic people, and is more commonly reported by females than males.

Risk-Averse Newsvendor Model with Strategic Consumer Behavior

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Tie Wang

2013-01-01

Full Text Available The classic newsvendor problem focuses on maximizing the expected profit or minimizing the expected cost when the newsvendor faces myopic customers. However, it ignores the customer’s bargain-hunting behavior and risk preference measure of the newsvendor. As a result, we carry out the rational expectation (RE equilibrium analysis for risk-averse newsvendor facing forward-looking customers who anticipate future sales and choose purchasing timing to maximize their expected surplus. We propose the equations satisfied by the RE equilibrium price and quantity for the risk-averse retailer in general setting and the explicit equilibrium decisions for the case where demand follows the uniform distribution and utility is a general power function. We identify the impacts of the system parameters on the RE equilibrium for this specific situation. In particular, we show that the RE equilibrium price for some risk-averse newsvendors is lower than for a risk-neutral retailer and the RE equilibrium stocking quantity for some risk-averse newsvendors is higher than for a risk-neutral retailer. We also find that the RE equilibrium sale price for a risk-averse newsvendor is decreasing in salvage price in some situations.

Optimal Consumption and Investment under Time-Varying Relative Risk Aversion

DEFF Research Database (Denmark)

Steffensen, Mogens

2011-01-01

We consider the continuous time consumption-investment problem originally formalized and solved by Merton in case of constant relative risk aversion. We present a complete solution for the case where relative risk aversion with respect to consumption varies with time, having in mind an investor...... with age-dependent risk aversion. This provides a new motivation for life-cycle investment rules. We study the optimal consumption and investment rules, in particular in the case where the relative risk aversion with respect to consumption is increasing with age....

Self-Other Decision Making and Loss Aversion

Science.gov (United States)

Polman, Evan

2012-01-01

In eight studies, we tested the prediction that making choices for others involves less loss aversion than making choices for the self. We found that loss aversion is significantly lessened among people choosing for others in scenarios describing riskless choice (Study 1), gambling (Studies 2 and 3), and social aspects of life, such as likeably…

Aversive smell associations shape social judgment

OpenAIRE

Homan, Philipp; Ely, Benjamin A.; Yuan, May; Brosch, Tobias; Ng, John; Trope, Yaacov; Schiller, Daniela

2017-01-01

Once associating another person with an unpleasant smell, how do we perceive and judge this person from that moment on? Here, we used aversive olfactory conditioning followed by a social attribution task during functional magnetic resonance imaging to address this question. After conditioning, where one of two faces was repeatedly paired with an aversive smell, the participants reported negative affect when viewing the smell-conditioned but not the neutral face. When subsequently confronted w...

Memory reconsolidation in aversive and appetitive settings

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Amy Claire Reichelt

2013-09-01

Full Text Available Memory reconsolidation has been observed across species and in a number of behavioural paradigms. The majority of memory reconsolidation studies have been carried out in pavlovian fear conditioning and other aversive memory settings, with potential implications for the treatment of post-traumatic stress disorder. However, there is a growing literature on memory reconsolidation in appetitive reward-related memory paradigms, including translational models of drug addiction. While there appears to be substantial similarity in the basic phenomenon and underlying mechanisms of memory reconsolidation across unconditioned stimulus valence, there are also notable discrepancies. These arise both when comparing aversive to appetitive paradigms and also across different paradigms within the same valence of memory. We review the demonstration of memory reconsolidation across different aversive and appetitive memory paradigms, the commonalities and differences in underlying mechanisms and the conditions under which each memory undergoes reconsolidation. We focus particularly on whether principles derived from the aversive literature are applicable to appetitive settings, and also whether the expanding literature in appetitive paradigms is informative for fear memory reconsolidation.

Characterizing the genetic influences on risk aversion.

Science.gov (United States)

Harrati, Amal

2014-01-01

Risk aversion has long been cited as an important factor in retirement decisions, investment behavior, and health. Some of the heterogeneity in individual risk tolerance is well understood, reflecting age gradients, wealth gradients, and similar effects, but much remains unexplained. This study explores genetic contributions to heterogeneity in risk aversion among older Americans. Using over 2 million genetic markers per individual from the U.S. Health and Retirement Study, I report results from a genome-wide association study (GWAS) on risk preferences using a sample of 10,455 adults. None of the single-nucleotide polymorphisms (SNPs) are found to be statistically significant determinants of risk preferences at levels stricter than 5 × 10(-8). These results suggest that risk aversion is a complex trait that is highly polygenic. The analysis leads to upper bounds on the number of genetic effects that could exceed certain thresholds of significance and still remain undetected at the current sample size. The findings suggest that the known heritability in risk aversion is likely to be driven by large numbers of genetic variants, each with a small effect size.

Complexity and competition in appetitive and aversive neural circuits

Directory of Open Access Journals (Sweden)

Crista L. Barberini

2012-11-01

Full Text Available Decision-making often involves using sensory cues to predict possible rewarding or punishing reinforcement outcomes before selecting a course of action. Recent work has revealed complexity in how the brain learns to predict rewards and punishments. Analysis of neural signaling during and after learning in the amygdala and orbitofrontal cortex, two brain areas that process appetitive and aversive stimuli, reveals a dynamic relationship between appetitive and aversive circuits. Specifically, the relationship between signaling in appetitive and aversive circuits in these areas shifts as a function of learning. Furthermore, although appetitive and aversive circuits may often drive opposite behaviors – approaching or avoiding reinforcement depending upon its valence – these circuits can also drive similar behaviors, such as enhanced arousal or attention; these processes also may influence choice behavior. These data highlight the formidable challenges ahead in dissecting how appetitive and aversive neural circuits interact to produce a complex and nuanced range of behaviors.

Decision-Making in Suicidal Behavior: The Protective Role of Loss Aversion.

Science.gov (United States)

Hadlaczky, Gergö; Hökby, Sebastian; Mkrtchian, Anahit; Wasserman, Danuta; Balazs, Judit; Machín, Núria; Sarchiapone, Marco; Sisask, Merike; Carli, Vladimir

2018-01-01

Loss aversion is a central and well operationalized trait behavior that describes the tendency for humans to strongly prefer avoiding losses to making equivalent gains. Human decision-making is thus biased toward safer choices. The aim of this study was to explore the relationship between loss aversion and suicidal behavior in a large cohort of adolescents recruited in 30 schools of seven European countries for a longitudinal study (Current Controlled Trials ISRCTN65120704). We hypothesized that individuals with higher loss aversion would be less likely to attempt suicide. A mixed monetary gamble task was used to generate loss aversion scores for each participant. Logistic regression was used to estimate the cross-sectional association between loss aversion and life-time suicide attempts in the baseline sample ( N  = 2,158; 156 attempters), and incident attempts were predicted in a 4-month prospective model ( N  = 1,763; 75 attempters). Multiple regression was used to estimate the association between loss aversion and suicidal ideation. Loss aversion was a significant predictor of attempted suicide in both the cross-sectional (OR = 0.79; P  = 0.005) and prospective analysis (OR = 0.81; P  = 0.040), adjusting for depression, anxiety, stress, and sex. The correlation between pre and post measures of loss aversion was r  = 0.52 ( P  loss aversion was not (cross-sectional model: P  = 0.092; Prospective model: P  = 0.390). This suggests that the concept of loss aversion may be useful in understanding the transition from suicidal thoughts to attempts. This and previous studies suggest that altered decision-making is involved in suicide attempts. In our study, we show the involvement of loss aversion in particular, and propose that individuals high in loss aversion are discouraged from carrying out the suicide attempt because of a greater focus on the negative consequences of the decision.

Loss aversion and 5HTT gene variants in adolescent anxiety

Directory of Open Access Journals (Sweden)

Monique Ernst

2014-04-01

Full Text Available Loss aversion, a well-documented behavioral phenomenon, characterizes decisions under risk in adult populations. As such, loss aversion may provide a reliable measure of risky behavior. Surprisingly, little is known about loss aversion in adolescents, a group who manifests risk-taking behavior, or in anxiety disorders, which are associated with risk-avoidance. Finally, loss aversion is expected to be modulated by genotype, particularly the serotonin transporter (SERT gene variant, based on its role in anxiety and impulsivity. This genetic modulation may also differ between anxious and healthy adolescents, given their distinct propensities for risk taking. The present work examines the modulation of loss aversion, an index of risk-taking, and reaction-time to decision, an index of impulsivity, by the serotonin-transporter-gene-linked polymorphisms (5HTTLPR in healthy and clinically anxious adolescents. Findings show that loss aversion (1 does manifest in adolescents, (2 does not differ between healthy and clinically anxious participants, and (3, when stratified by SERT genotype, identifies a subset of anxious adolescents who are high SERT-expressers, and show excessively low loss-aversion and high impulsivity. This last finding may serve as preliminary evidence for 5HTTLPR as a risk factor for the development of comorbid disorders associated with risk-taking and impulsivity in clinically anxious adolescents.

Thinking like a trader selectively reduces individuals' loss aversion.

Science.gov (United States)

Sokol-Hessner, Peter; Hsu, Ming; Curley, Nina G; Delgado, Mauricio R; Camerer, Colin F; Phelps, Elizabeth A

2009-03-31

Research on emotion regulation has focused upon observers' ability to regulate their emotional reaction to stimuli such as affective pictures, but many other aspects of our affective experience are also potentially amenable to intentional cognitive regulation. In the domain of decision-making, recent work has demonstrated a role for emotions in choice, although such work has generally remained agnostic about the specific role of emotion. Combining psychologically-derived cognitive strategies, physiological measurements of arousal, and an economic model of behavior, this study examined changes in choices (specifically, loss aversion) and physiological correlates of behavior as the result of an intentional cognitive regulation strategy. Participants were on average more aroused per dollar to losses relative to gains, as measured with skin conductance response, and the difference in arousal to losses versus gains correlated with behavioral loss aversion across subjects. These results suggest a specific role for arousal responses in loss aversion. Most importantly, the intentional cognitive regulation strategy, which emphasized "perspective-taking," uniquely reduced both behavioral loss aversion and arousal to losses relative to gains, largely by influencing arousal to losses. Our results confirm previous research demonstrating loss aversion while providing new evidence characterizing individual differences and arousal correlates and illustrating the effectiveness of intentional regulation strategies in reducing loss aversion both behaviorally and physiologically.

Health shocks and risk aversion.

Science.gov (United States)

Decker, Simon; Schmitz, Hendrik

2016-12-01

We empirically assess whether a health shock influences individual risk aversion. We use grip strength data to obtain an objective health shock indicator. In order to account for the non-random nature of our data regression-adjusted matching is employed. Risk preferences are traditionally assumed to be constant. However, we find that a health shock increases individual risk aversion. The finding is robust to a series of sensitivity analyses and persists for at least four years after the shock. Income changes do not seem to be the driving mechanism. Copyright © 2016 Elsevier B.V. All rights reserved.

Probability Weighting and Loss Aversion in Futures Hedging

NARCIS (Netherlands)

Mattos, F.; Garcia, P.; Pennings, J.M.E.

2008-01-01

We analyze how the introduction of probability weighting and loss aversion in a futures hedging model affects decision making. Analytical findings indicate that probability weighting alone always affects optimal hedge ratios, while loss and risk aversion only have an impact when probability

Feasible sets, comparative risk aversion, and comparative uncertainty aversion in bargaining

NARCIS (Netherlands)

Driesen, B.W.I.; Lombardi, M.; Peters, H.J.M.

2015-01-01

We study feasible sets of the bargaining problem under two different assumptions: the players are subjective expected utility maximizers or the players are Choquet expected utility maximizers. For the latter case, we consider the effects on bargaining solutions when players become more risk averse

Combined Effects of Glucocorticoid and Noradrenergic Activity on Loss Aversion.

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Margittai, Zsofia; Nave, Gideon; Van Wingerden, Marijn; Schnitzler, Alfons; Schwabe, Lars; Kalenscher, Tobias

2018-01-01

Loss aversion is a well-known behavioral regularity in financial decision making, describing humans' tendency to overweigh losses compared to gains of the same amount. Recent research indicates that stress and associated hormonal changes affect loss aversion, yet the underlying neuroendocrine mechanisms are still poorly understood. Here, we investigated the causal influence of two major stress neuromodulators, cortisol and noradrenaline, on loss aversion during financial decision making. In a double-blind, placebo-controlled between-subject design, we orally administered either the α2-adrenergic antagonist yohimbine (increasing noradrenergic stimulation), hydrocortisone, both substances, or a placebo to healthy young men. We tested the treatments' influence on a financial decision-making task measuring loss aversion and risk attitude. We found that both drugs combined, relative to either drug by itself, reduced loss aversion in the absence of an effect on risk attitude or choice consistency. Our data suggest that concurrent glucocorticoid and noradrenergic activity prompts an alignment of reward- with loss-sensitivity, and thus diminishes loss aversion. Our results have implications for the understanding of the susceptibility to biases in decision making.

Does ambiguity aversion survive in experimental asset markets?

NARCIS (Netherlands)

Füllbrunn, Sascha; Rau, Holger A.; Weitzel, Utz

2014-01-01

Although a number of theoretical studies explain empirical puzzles in finance with ambiguity aversion, it is not a given that individual ambiguity attitudes survive in markets. In fact, despite ample evidence of ambiguity aversion in individual decision making, most studies find no or only limited

Inequity aversion revisted

NARCIS (Netherlands)

Yang, Y.; Onderstal, S.; Schram, A.

2012-01-01

We provide the first systematic study of the robustness of parameter estimates for the Fehr-Schmidt (1999) model of inequity aversion with respect to (i) the occurrence of efficiency concerns; (ii) the scale of payoffs; and (iii) the game used (i.e., cross-game consistency). Moreover, we provide

Risk Aversion and Expected-Utility Theory: A Calibration Theorem.

OpenAIRE

Matthew Rabin.

2000-01-01

Within the expected-utility framework, the only explanation for risk aversion is that the utility function for wealth is concave: A person has lower marginal utility for additional wealth when she is wealthy than when she is poor. This paper provides a theorem showing that expected-utility theory is an utterly implausible explanation for appreciable risk aversion over modest stakes: Within expected-utility theory, for any concave utility function, even very little risk aversion over modest st...

Narp regulates long-term aversive effects of morphine withdrawal

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Reti, Irving M.; Crombag, Hans S.; Takamiya, Kogo; Sutton, Jeffrey M.; Guo, Ning; Dinenna, Megan L.; Huganir, Richard L.; Holland, Peter C.; Baraban, Jay M.

2008-01-01

Although long-lasting effects of drug withdrawal are thought to play a key role in motivating continued drug use, the mechanisms mediating this type of drug-induced plasticity are unclear. As Narp is an immediate early gene product that is secreted at synaptic sites and binds to AMPA receptors, it has been implicated in mediating enduring forms of synaptic plasticity. In previous studies, we found that Narp is selectively induced by morphine withdrawal in the extended amygdala, a group of limbic nuclei that mediate aversive behavioral responses. Accordingly, in this study, we evaluated whether long-term aversive effects of morphine withdrawal are altered in Narp KO mice. We found that acute physical signs of morphine withdrawal are unaffected by Narp deletion. However, Narp KO mice acquire and sustain more aversive responses to the environment conditioned with morphine withdrawal than WT controls. Paradoxically, Narp KO mice undergo accelerated extinction of this heightened aversive response. Taken together, these studies suggest that Narp modulates both acquisition and extinction of aversive responses to morphine withdrawal and, therefore, may regulate plasticity processes underlying drug addiction. PMID:18729628

Loss aversion and 5HTT gene variants in adolescent anxiety.

Science.gov (United States)

Ernst, Monique; Plate, Rista C; Carlisi, Christina O; Gorodetsky, Elena; Goldman, David; Pine, Daniel S

2014-04-01

Loss aversion, a well-documented behavioral phenomenon, characterizes decisions under risk in adult populations. As such, loss aversion may provide a reliable measure of risky behavior. Surprisingly, little is known about loss aversion in adolescents, a group who manifests risk-taking behavior, or in anxiety disorders, which are associated with risk-avoidance. Finally, loss aversion is expected to be modulated by genotype, particularly the serotonin transporter (SERT) gene variant, based on its role in anxiety and impulsivity. This genetic modulation may also differ between anxious and healthy adolescents, given their distinct propensities for risk taking. The present work examines the modulation of loss aversion, an index of risk-taking, and reaction-time to decision, an index of impulsivity, by the serotonin-transporter-gene-linked polymorphisms (5HTTLPR) in healthy and clinically anxious adolescents. Findings show that loss aversion (1) does manifest in adolescents, (2) does not differ between healthy and clinically anxious participants, and (3), when stratified by SERT genotype, identifies a subset of anxious adolescents who are high SERT-expressers, and show excessively low loss-aversion and high impulsivity. This last finding may serve as preliminary evidence for 5HTTLPR as a risk factor for the development of comorbid disorders associated with risk-taking and impulsivity in clinically anxious adolescents. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Myopic loss aversion: Potential causes of replication failures

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Alexander Klos

2013-09-01

Full Text Available This paper presents two studies on narrow bracketing and myopic loss aversion. The first study shows that the tendency to segregate multiple gambles is eliminated if subjects face a certainty equivalent or a probability equivalent task instead of a binary choice. The second study argues that the behavioral differences previously attributed entirely to myopic loss aversion are partly because long-term return properties are simply easier to grasp if the return information is already provided in the form of long-term returns rather than one-year returns. Both results may be related to recent failures to replicate myopic loss aversion. When the choice situation is structured in such a way that it draws respondents' attention to the final outcome distribution and/or if severe misestimations of long-term returns based on short-term return information are unlikely, behavioral differences consistent with myopic loss aversion are less likely to be observed.

Loss Aversion Reflects Information Accumulation, Not Bias: A Drift-Diffusion Model Study.

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Clay, Summer N; Clithero, John A; Harris, Alison M; Reed, Catherine L

2017-01-01

Defined as increased sensitivity to losses, loss aversion is often conceptualized as a cognitive bias. However, findings that loss aversion has an attentional or emotional regulation component suggest that it may instead reflect differences in information processing. To distinguish these alternatives, we applied the drift-diffusion model (DDM) to choice and response time (RT) data in a card gambling task with unknown risk distributions. Loss aversion was measured separately for each participant. Dividing the participants into terciles based on loss aversion estimates, we found that the most loss-averse group showed a significantly lower drift rate than the other two groups, indicating overall slower uptake of information. In contrast, neither the starting bias nor the threshold separation (barrier) varied by group, suggesting that decision thresholds are not affected by loss aversion. These results shed new light on the cognitive mechanisms underlying loss aversion, consistent with an account based on information accumulation.

Aversion to ambiguity and willingness to take risks affect therapeutic decisions in managing atrial fibrillation for stroke prevention: results of a pilot study in family physicians.

Science.gov (United States)

Raptis, Stavroula; Chen, Jia Ning; Saposnik, Florencia; Pelyavskyy, Roman; Liuni, Andrew; Saposnik, Gustavo

2017-01-01

Anticoagulation is the therapeutic paradigm for stroke prevention in patients with atrial fibrillation (AF). It is unknown how physicians make treatment decisions in primary stroke prevention for patients with AF. To evaluate the association between family physicians' risk preferences (aversion risk and ambiguity) and therapeutic recommendations (anticoagulation) in the management of AF for primary stroke prevention by applying concepts from behavioral economics. Overall, 73 family physicians participated and completed the study. Our study comprised seven simulated case vignettes, three behavioral experiments, and two validated surveys. Behavioral experiments and surveys incorporated an economic framework to determine risk preferences and biases (e.g., ambiguity aversion, willingness to take risks). The primary outcome was making the correct decision of anticoagulation therapy. Secondary outcomes included medical errors in the management of AF for stroke prevention. Overall, 23.3% (17/73) of the family physicians elected not to escalate the therapy from antiplatelets to anticoagulation when recommended by best practice guidelines. A total of 67.1% of physicians selected the correct therapeutic options in two or more of the three simulated case vignettes. Multivariate analysis showed that aversion to ambiguity was associated with appropriate change to anticoagulation therapy in the management of AF (OR 5.48, 95% CI 1.08-27.85). Physicians' willingness to take individual risk in multiple domains was associated with lower errors (OR 0.16, 95% CI 0.03-0.86). Physicians' aversion to ambiguity and willingness to take risks are associated with appropriate therapeutic decisions in the management of AF for primary stroke prevention. Further large scale studies are needed.

Children do not exhibit ambiguity aversion despite intact familiarity bias.

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Li, Rosa; Brannon, Elizabeth M; Huettel, Scott A

2014-01-01

The phenomenon of ambiguity aversion, in which risky gambles with known probabilities are preferred over ambiguous gambles with unknown probabilities, has been thoroughly documented in adults but never measured in children. Here, we use two distinct tasks to investigate ambiguity preferences of children (8- to 9-year-olds) and a comparison group of adults (19- to 27-year-olds). Across three separate measures, we found evidence for significant ambiguity aversion in adults but not in children and for greater ambiguity aversion in adults compared to children. As ambiguity aversion in adults has been theorized to result from a preference to bet on the known and avoid the unfamiliar, we separately measured familiarity bias and found that children, like adults, are biased towards the familiar. Our findings indicate that ambiguity aversion emerges across the course of development between childhood and adolescence, while a familiarity bias is already present in childhood.

Further evidence for conditioned taste aversion induced by forced swimming.

Science.gov (United States)

Masaki, Takahisa; Nakajima, Sadahiko

2005-01-31

A series of experiments with rats reported that aversion to a taste solution can be established by forced swimming in a water pool. Experiment 1 demonstrated that correlation of taste and swimming is a critical factor for this phenomenon, indicating associative (i.e., Pavlovian) nature of this learning. Experiment 2 showed that this learning obeys the Pavlovian law of strength, by displaying a positive relationship between the duration of water immersion in training and the taste aversion observed in subsequent testing. Experiment 3 revealed that swimming rather than being wet is the critical agent, because a water shower did not endow rats with taste aversion. Experiment 4 found that taste aversion was a positive function of water level of the pools in training (0, 12 or 32 cm). These results, taken together, suggest that energy expenditure caused by physical exercise might be involved in the development of taste aversion.

Loss-Averse Retailer’s Optimal Ordering Policies for Perishable Products with Customer Returns

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Xu Chen

2014-01-01

Full Text Available We investigate the loss-averse retailer’s ordering policies for perishable product with customer returns. With the introduction of the segmental loss utility function, we depict the retailer’s loss aversion decision bias and establish the loss-averse retailer’s ordering policy model. We derive that the loss-averse retailer’s optimal order quantity with customer returns exists and is unique. By comparison, we obtain that both the risk-neutral and the loss-averse retailer’s optimal order quantities depend on the inventory holding cost and the marginal shortage cost. Through the sensitivity analysis, we also discuss the effect of loss-averse coefficient and the ratio of return on the loss-averse retailer’s optimal order quantity with customer returns.

Anxiety and spatial attention moderate the electrocortical response to aversive pictures.

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MacNamara, Annmarie; Hajcak, Greg

2009-11-01

Aversive stimuli capture attention and elicit increased neural activity, as indexed by behavioral, electrocortical and hemodynamic measures; moreover, individual differences in anxiety relate to a further increased sensitivity to threatening stimuli. Evidence has been mixed, however, as to whether aversive pictures elicit increased neural response when presented in unattended spatial locations. In the current study, ERP and behavioral data were recorded from 49 participants as aversive and neutral pictures were simultaneously presented in spatially attended and unattended locations; on each trial, participants made same/different judgments about pictures presented in attended locations. Aversive images presented in unattended locations resulted in increased error rate and reaction time. The late positive potential (LPP) component of the ERP was only larger when aversive images were presented in attended locations, and this increase was positively correlated with self-reported state anxiety. Findings are discussed in regard to the sensitivity of ERP and behavioral responses to aversive distracters, and in terms of increased neural processing of threatening stimuli in anxiety.

Loss Aversion Reflects Information Accumulation, Not Bias: A Drift-Diffusion Model Study

Directory of Open Access Journals (Sweden)

Summer N. Clay

2017-10-01

Full Text Available Defined as increased sensitivity to losses, loss aversion is often conceptualized as a cognitive bias. However, findings that loss aversion has an attentional or emotional regulation component suggest that it may instead reflect differences in information processing. To distinguish these alternatives, we applied the drift-diffusion model (DDM to choice and response time (RT data in a card gambling task with unknown risk distributions. Loss aversion was measured separately for each participant. Dividing the participants into terciles based on loss aversion estimates, we found that the most loss-averse group showed a significantly lower drift rate than the other two groups, indicating overall slower uptake of information. In contrast, neither the starting bias nor the threshold separation (barrier varied by group, suggesting that decision thresholds are not affected by loss aversion. These results shed new light on the cognitive mechanisms underlying loss aversion, consistent with an account based on information accumulation.

Risk Aversion, Loss Aversion, and the Demand for Insurance

Directory of Open Access Journals (Sweden)

Louis Eeckhoudt

2018-05-01

Full Text Available In this paper we analyze insurance demand when the utility function depends both upon final wealth and the level of losses or gains relative to a reference point. Besides some comparative statics results, we discuss the links with first-order risk aversion, with the Omega measure, and with a tendency to over-insure modest risks that has been been extensively documented in real insurance markets.

RELATIONSHIP BETWEEN THE TASK AVERSIVENESS AND ACADEMIC PROCRASTINATION

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Magvirasari Lestari Linra

2016-12-01

Full Text Available Academic procrastination occurs when certain tasks are considered unpleasant, an unpleasant task and the usual delayed them is the task of writing, reading, studying for the exam, meetings, and administrative. The purpose of this study was to determine the relationship of the task aversiveness with academic procrastination. Subject of the study were 100 students out of a population of 516 students of the Faculty of Psychology class of 2012-2014. The method used in this research is quantitative by using Spearman rho as data analysis techniques. The research instrument consists of academic procrastination scale and the scale of the task aversiveness. Based on the results of correlation is known that there is a positive relationship between task aversiveness with academic procrastination with a correlation coefficient r = 0.508; p = 0.000. The results showed that of the 100 students of the Faculty of Psychology University of Makassar has a degree of relationship between task aversiveness with academic procrastination is on the very low category (25, 8%. Area / types of tasks delayed is not necessarily an unpleasant task and otherwise unpleasant task may not be postponed. Area task the highest level of aversive and delays are areas the task of writing and reading. This study illustrates that academic procrastination can be lowered by a change in the mindset of an unpleasant task.

Cognitive function is associated with risk aversion in community-based older persons.

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Boyle, Patricia A; Yu, Lei; Buchman, Aron S; Laibson, David I; Bennett, David A

2011-09-11

Emerging data from younger and middle-aged persons suggest that cognitive ability is negatively associated with risk aversion, but this association has not been studied among older persons who are at high risk of experiencing loss of cognitive function. Using data from 369 community-dwelling older persons without dementia from the Rush Memory and Aging Project, an ongoing longitudinal epidemiologic study of aging, we examined the correlates of risk aversion and tested the hypothesis that cognition is negatively associated with risk aversion. Global cognition and five specific cognitive abilities were measured via detailed cognitive testing, and risk aversion was measured using standard behavioral economics questions in which participants were asked to choose between a certain monetary payment ($15) versus a gamble in which they could gain more than $15 or gain nothing; potential gamble gains ranged from $21.79 to $151.19 with the gain amounts varied randomly over questions. We first examined the bivariate associations of age, education, sex, income and cognition with risk aversion. Next, we examined the associations between cognition and risk aversion via mixed models adjusted for age, sex, education, and income. Finally, we conducted sensitivity analyses to ensure that our results were not driven by persons with preclinical cognitive impairment. In bivariate analyses, sex, education, income and global cognition were associated with risk aversion. However, in a mixed effect model, only sex (estimate = -1.49, standard error (SE) = 0.39, p risk aversion. Thus, a lower level of global cognitive function and female sex were associated with greater risk aversion. Moreover, performance on four out of the five cognitive domains was negatively related to risk aversion (i.e., semantic memory, episodic memory, working memory, and perceptual speed); performance on visuospatial abilities was not. A lower level of cognitive ability and female sex are associated with greater

Gender differences in financial risk aversion and career choices are affected by testosterone.

Science.gov (United States)

Sapienza, Paola; Zingales, Luigi; Maestripieri, Dario

2009-09-08

Women are generally more risk averse than men. We investigated whether between- and within-gender variation in financial risk aversion was accounted for by variation in salivary concentrations of testosterone and in markers of prenatal testosterone exposure in a sample of >500 MBA students. Higher levels of circulating testosterone were associated with lower risk aversion among women, but not among men. At comparably low concentrations of salivary testosterone, however, the gender difference in risk aversion disappeared, suggesting that testosterone has nonlinear effects on risk aversion regardless of gender. A similar relationship between risk aversion and testosterone was also found using markers of prenatal testosterone exposure. Finally, both testosterone levels and risk aversion predicted career choices after graduation: Individuals high in testosterone and low in risk aversion were more likely to choose risky careers in finance. These results suggest that testosterone has both organizational and activational effects on risk-sensitive financial decisions and long-term career choices.

Enhanced striatal sensitivity to aversive reinforcement in adolescents versus adults.

Science.gov (United States)

Galván, Adriana; McGlennen, Kristine M

2013-02-01

Neurodevelopmental changes in mesolimbic regions are associated with adolescent risk-taking behavior. Numerous studies have shown exaggerated activation in the striatum in adolescents compared with children and adults during reward processing. However, striatal sensitivity to aversion remains elusive. Given the important role of the striatum in tracking both appetitive and aversive events, addressing this question is critical to understanding adolescent decision-making, as both positive and negative factors contribute to this behavior. In this study, human adult and adolescent participants performed a task in which they received squirts of appetitive or aversive liquid while undergoing fMRI, a novel approach in human adolescents. Compared with adults, adolescents showed greater behavioral and striatal sensitivity to both appetitive and aversive stimuli, an effect that was exaggerated in response to delivery of the aversive stimulus. Collectively, these findings contribute to understanding how neural responses to positive and negative outcomes differ between adolescents and adults and how they may influence adolescent behavior.

Are group members less inequality averse than individual decision makers?

OpenAIRE

He, Haoran; Villeval, Marie Claire

2017-01-01

International audience; We compare inequality aversion in individuals and teams by means of both within- and between-subject experimental designs, and we investigate how teams aggregate individual preferences. We find that team decisions reveal less inequality aversion than individual initial proposals in team decision-making. However, teams are no more selfish than individuals who decide in isolation. Individuals express strategically more inequality aversion in their initial proposals in te...

The role of risk aversion in non-conscious decision making.

Science.gov (United States)

Wang, Shuo; Krajbich, Ian; Adolphs, Ralph; Tsuchiya, Naotsugu

2012-01-01

To what extent can people choose advantageously without knowing why they are making those choices? This hotly debated question has capitalized on the Iowa Gambling Task (IGT), in which people often learn to choose advantageously without appearing to know why. However, because the IGT is unconstrained in many respects, this finding remains debated and other interpretations are possible (e.g., risk aversion, ambiguity aversion, limits of working memory, or insensitivity to reward/punishment can explain the finding of the IGT). Here we devised an improved variant of the IGT in which the deck-payoff contingency switches after subjects repeatedly choose from a good deck, offering the statistical power of repeated within-subject measures based on learning the reward contingencies associated with each deck. We found that participants exhibited low confidence in their choices, as probed with post-decision wagering, despite high accuracy in selecting advantageous decks in the task, which is putative evidence for non-conscious decision making. However, such a behavioral dissociation could also be explained by risk aversion, a tendency to avoid risky decisions under uncertainty. By explicitly measuring risk aversion for each individual, we predicted subjects' post-decision wagering using Bayesian modeling. We found that risk aversion indeed does play a role, but that it did not explain the entire effect. Moreover, independently measured risk aversion was uncorrelated with risk aversion exhibited during our version of the IGT, raising the possibility that the latter risk aversion may be non-conscious. Our findings support the idea that people can make optimal choices without being fully aware of the basis of their decision. We suggest that non-conscious decision making may be mediated by emotional feelings of risk that are based on mechanisms distinct from those that support cognitive assessment of risk.

Risk Aversion and Emotions

NARCIS (Netherlands)

Nguyen, Y.; Noussair, C.N.

2013-01-01

Abstract: We consider the relationship between emotions and decision-making under risk. Specifically, we examine the emotional correlates of risk-averse decisions. In our experiment, individuals' facial expressions are monitored with facereading software, as they are presented with risky lotteries.

Are team members less inequality averse than individual decision makers?

OpenAIRE

Haoran He; Marie Claire Villeval

2014-01-01

révision Août 2015; We compare inequality aversion in individuals and teams by means of both within- and between-subject experimental designs, and we investigate how teams aggregate individual preferences. We find that team decisions reveal less inequality aversion than individual initial proposals in team decision-making. However, teams are no more selfish than individuals who decide in isolation. Individuals express strategically more inequality aversion in their initial proposals in team d...

Common brain activations for painful and non-painful aversive stimuli

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Hayes Dave J

2012-06-01

Full Text Available Abstract Background Identification of potentially harmful stimuli is necessary for the well-being and self-preservation of all organisms. However, the neural substrates involved in the processing of aversive stimuli are not well understood. For instance, painful and non-painful aversive stimuli are largely thought to activate different neural networks. However, it is presently unclear whether there is a common aversion-related network of brain regions responsible for the basic processing of aversive stimuli. To help clarify this issue, this report used a cross-species translational approach in humans (i.e. meta-analysis and rodents (i.e. systematic review of functional neuroanatomy. Results Animal and human data combined to show a core aversion-related network, consisting of similar cortical (i.e. MCC, PCC, AI, DMPFC, RTG, SMA, VLOFC; see results section or abbreviation section for full names and subcortical (i.e. Amyg, BNST, DS, Hab, Hipp/Parahipp, Hyp, NAc, NTS, PAG, PBN, raphe, septal nuclei, Thal, LC, midbrain regions. In addition, a number of regions appeared to be more involved in pain-related (e.g. sensory cortex or non-pain-related (e.g. amygdala aversive processing. Conclusions This investigation suggests that aversive processing, at the most basic level, relies on similar neural substrates, and that differential responses may be due, in part, to the recruitment of additional structures as well as the spatio-temporal dynamic activity of the network. This network perspective may provide a clearer understanding of why components of this circuit appear dysfunctional in some psychiatric and pain-related disorders.

Variant BDNF Val66Met polymorphism affects extinction of conditioned aversive memory.

Science.gov (United States)

Yu, Hui; Wang, Yue; Pattwell, Siobhan; Jing, Deqiang; Liu, Ting; Zhang, Yun; Bath, Kevin G; Lee, Francis S; Chen, Zhe-Yu

2009-04-01

Brain-derived neurotrophic factor (BDNF) plays important roles in activity-dependent plasticity processes, such as long-term potentiation, learning, and memory. The recently reported human BDNF Val66Met (BDNF(Met)) polymorphism has been shown to lead to altered hippocampal volume and impaired hippocampal-dependent memory and is associated with a variety of neuropsychiatric disorders. There are few studies, however, that investigate the effect of the BDNF(Met) polymorphism on hippocampal-independent memory processes. A conditioned taste aversion (CTA) task was used for studying the mechanisms of long-term, hippocampal-independent, nondeclarative memory in the mammalian brain. Using the CTA paradigm, we found a novel impairment in extinction learning, but not acquisition or retention, of aversive memories resulting from the variant BDNF(Met). BDNF(Met) mice were slower to extinguish an aversive CTA memory compared with wild-type counterparts. Moreover, the BDNF(Met) was associated with smaller volume and decreased neuronal dendritic complexity in the ventromedial prefrontal cortex (vmPFC), which plays a significant role in extinction of CTA. Finally, this delay in extinction learning could be rescued pharmacologically with a cognitive enhancer, d-cycloserine (DCS). To our knowledge, this is the first evidence that the BDNF(Met) polymorphism contributes to abnormalities in memory extinction. This abnormality in extinction learning may be explained by alterations in neuronal morphology, as well as decreased neural activity in the vmPFC. Importantly, DCS was effective in rescuing this delay in extinction, suggesting that when coupled with behavior therapy, DCS may be an effective treatment option for anxiety disorders in humans with this genetic variant BDNF.

Loss Aversion under Prospect Theory: a Parameter-Free Measurement

NARCIS (Netherlands)

H. Bleichrodt (Han); M. Abdellaoui (Mohammed); C. Paraschiv (Corina)

2007-01-01

textabstractA growing body of qualitative evidence shows that loss aversion, a phenomenon formalized in prospect theory, can explain a variety of field and experimental data. Quantifications of loss aversion are, however, hindered by the absence of a general preference-based method to elicit the

Aversive counterconditioning attenuates reward signalling in the ventral striatum

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Anne Marije Kaag

2016-08-01

Full Text Available Appetitive conditioning refers to the process of learning cue-reward associations and is mediated by the mesocorticolimbic system. Appetitive conditioned responses are difficult to extinguish, especially for highly salient rewards such as food and drugs. We investigate whether aversive counterconditioning can alter reward reinstatement in the ventral striatum in healthy volunteers using functional Magnetic Resonance Imaging (fMRI. In the initial conditioning phase, two different stimuli were reinforced with a monetary reward. In the subsequent counterconditioning phase, one of these stimuli was paired with an aversive shock to the wrist. In the following extinction phase, none of the stimuli were reinforced. In the final reinstatement phase, reward was reinstated by informing the participants that the monetary gain could be doubled. Our fMRI data revealed that reward signalling in the ventral striatum and ventral tegmental area following reinstatement was smaller for the stimulus that was counterconditioned with an electrical shock, compared to the non-counterconditioned stimulus. A functional connectivity analysis showed that aversive counterconditioning strengthened striatal connectivity with the hippocampus and insula. These results suggest that reward signalling in the ventral striatum can be attenuated through aversive counterconditioning, possibly by concurrent retrieval of the aversive association through enhanced connectivity with hippocampus and insula.

Differences in risk aversion between young and older adults

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Albert SM

2012-02-01

Full Text Available Steven M Albert1, John Duffy21Department of Behavioral and Community Health Sciences, 2Department of Economics, University of Pittsburgh, Pittsburgh, PA, USAAbstract: Research on decision-making strategies among younger and older adults suggests that older adults may be more risk averse than younger people in the case of potential losses. These results mostly come from experimental studies involving gambling paradigms. Since these paradigms involve substantial demands on memory and learning, differences in risk aversion or other features of decision making attributed to age may in fact reflect age-related declines in cognitive abilities. In the current study, older and younger adults completed a simpler, paired lottery choice task used in the experimental economics literature to elicit risk aversion. A similar approach was used to elicit participants' discount rates. The older adult group was more risk averse than the younger (P < 0.05 and had a higher discount rate (15.6%–21.0% versus 10.3%–15.5%, P < 0.01, indicating lower expected utility from future income. Risk aversion and implied discount rates were weakly correlated. It may be valuable to investigate developmental changes in neural correlates of decision making across the lifespan.Keywords: aging, decision making, risk, time preference, behavioral economics

Coordination of a Random Yield Supply Chain with a Loss-Averse Supplier

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Jiarong Luo

2015-01-01

Full Text Available This paper investigates the coordination of a supply chain consisting of a loss-averse supplier and a risk-neutral buyer who orders products from the supplier who suffers from random yield to meet a deterministic demand. We derive the risk-neutral buyer’s optimal order policy and the loss-averse supplier’s optimal production policy under shortage-penalty-surplus-subsidy (SPSS contracts. We also analyze the impacts of loss aversion on the loss-averse supplier’s production decision making and find that the loss-averse supplier may produce less than, equal to, or more than the risk-neutral supplier. Then, we provide explicit conditions on which the random yield supply chain with a loss-averse supplier can be coordinated under SPSS contracts. Finally, adopting numerical examples, we find that when the shortage penalty is low, the buyer’s optimal order quantity will increase, while the supplier’s optimal production quantity will first decrease and then increase as the loss aversion level increases. When the shortage penalty is high, the buyer’s optimal order quantity will decrease but the supplier’s optimal production quantity will always increase as the loss aversion level increases. Furthermore, the numerical examples provide strong evidence for the view that SPSS contracts can effectively improve the performance of the whole supply chain.

Genotype Modulates Age-Related Alterations in Sensitivity to the Aversive Effects of Ethanol: An 8 Inbred Strain Analysis of Conditioned Taste Aversion

Science.gov (United States)

Moore, Eileen M.; Forrest, Robert D.; Boehm, Stephen L.

2012-01-01

Adolescent individuals display altered behavioral sensitivity to ethanol, which may contribute to the increased ethanol consumption seen in this age-group. However, genetics also exert considerable influence on both ethanol intake and sensitivity. Thus far there is little research assessing the combined influence of developmental and genetic alcohol sensitivities. Sensitivity to the aversive effects of ethanol using a conditioned taste aversion (CTA) procedure was measured during both adolescence (P30) and adulthood (P75) in 8 inbred mouse strains (C57BL/6J, DBA/2J, 129S1/SvImJ, A/J, BALB/cByJ, BTBR T+tf/J, C3H/HeJ, and FVB/NJ). Adolescent and adult mice were water deprived, and subsequently provided with access to 0.9% (v/v) NaCl solution for 1h. Immediately following access mice were administered ethanol (0, 1.5, 2.25, 3g/kg, ip). This procedure was repeated in 72h intervals for a total of 5 CTA trials. Sensitivity to the aversive effects of ethanol was highly dependent upon both strain and age. Within an inbred strain, adolescent animals were consistently less sensitive to the aversive effects of ethanol than their adult counterparts. However, the dose of ethanol required to produce an aversion response differed as a function of both age and strain. PMID:23171343

Neurocognitive development of risk aversion from early childhood to adulthood

Directory of Open Access Journals (Sweden)

David ePaulsen

2012-01-01

Full Text Available Human adults tend to avoid risk. In behavioral economic studies, risk aversion is manifest as a preference for sure gains over uncertain gains. However, children tend to be less averse to risk than adults. Given that many of the brain regions supporting decision making under risk do not reach maturity until late adolescence or beyond it is possible that mature risk-averse behavior may emerge from the development of decision-making circuitry. To explore this hypothesis, we tested 6- to 8-year-old children, 14- to 16-year-old adolescents, and young adults in a risky-decision task during functional magnetic resonance imaging (fMRI data acquisition. We found a number of decision-related brain regions to increase in activation with age during decision making, including areas associated with contextual memory retrieval and the incorporation of prior outcomes into the current decision-making strategy, e.g. insula, hippocampus and amygdala. Further, children who were more risk averse showed increased activation during decision making in vmPFC and ventral striatum. Our findings indicate that the emergence of adult levels of risk aversion co-occurs with the recruitment of regions supporting decision making under risk, including the integration of prior outcomes into current decision-making behavior. This pattern of results suggests that individual differences in the development of risk aversion may reflect differences in the maturation of these neural processes.

The strength of aversive and appetitive associations and maladaptive behaviors.

Science.gov (United States)

Itzhak, Yossef; Perez-Lanza, Daniel; Liddie, Shervin

2014-08-01

Certain maladaptive behaviors are thought to be acquired through classical Pavlovian conditioning. Exaggerated fear response, which can develop through Pavlovian conditioning, is associated with acquired anxiety disorders such as post-traumatic stress disorders (PTSDs). Inflated reward-seeking behavior, which develops through Pavlovian conditioning, underlies some types of addictive behavior (e.g., addiction to drugs, food, and gambling). These maladaptive behaviors are dependent on associative learning and the development of long-term memory (LTM). In animal models, an aversive reinforcer (fear conditioning) encodes an aversive contextual and cued LTM. On the other hand, an appetitive reinforcer results in conditioned place preference (CPP) that encodes an appetitive contextual LTM. The literature on weak and strong associative learning pertaining to the development of aversive and appetitive LTM is relatively scarce; thus, this review is particularly focused on the strength of associative learning. The strength of associative learning is dependent on the valence of the reinforcer and the salience of the conditioned stimulus that ultimately sways the strength of the memory trace. Our studies suggest that labile (weak) aversive and appetitive LTM may share similar signaling pathways, whereas stable (strong) aversive and appetitive LTM is mediated through different pathways. In addition, we provide some evidence suggesting that extinction of aversive fear memory and appetitive drug memory is likely to be mediated through different signaling molecules. We put forward the importance of studies aimed to investigate the molecular mechanisms underlying the development of weak and strong memories (aversive and appetitive), which would ultimately help in the development of targeted pharmacotherapies for the management of maladaptive behaviors that arise from classical Pavlovian conditioning. © 2014 International Union of Biochemistry and Molecular Biology.

Reappraising social insect behavior through aversive responsiveness and learning.

Science.gov (United States)

Roussel, Edith; Carcaud, Julie; Sandoz, Jean-Christophe; Giurfa, Martin

2009-01-01

The success of social insects can be in part attributed to their division of labor, which has been explained by a response threshold model. This model posits that individuals differ in their response thresholds to task-associated stimuli, so that individuals with lower thresholds specialize in this task. This model is at odds with findings on honeybee behavior as nectar and pollen foragers exhibit different responsiveness to sucrose, with nectar foragers having higher response thresholds to sucrose concentration. Moreover, it has been suggested that sucrose responsiveness correlates with responsiveness to most if not all other stimuli. If this is the case, explaining task specialization and the origins of division of labor on the basis of differences in response thresholds is difficult. To compare responsiveness to stimuli presenting clear-cut differences in hedonic value and behavioral contexts, we measured appetitive and aversive responsiveness in the same bees in the laboratory. We quantified proboscis extension responses to increasing sucrose concentrations and sting extension responses to electric shocks of increasing voltage. We analyzed the relationship between aversive responsiveness and aversive olfactory conditioning of the sting extension reflex, and determined how this relationship relates to division of labor. Sucrose and shock responsiveness measured in the same bees did not correlate, thus suggesting that they correspond to independent behavioral syndromes, a foraging and a defensive one. Bees which were more responsive to shock learned and memorized better aversive associations. Finally, guards were less responsive than nectar foragers to electric shocks, exhibiting higher tolerance to low voltage shocks. Consequently, foragers, which are more sensitive, were the ones learning and memorizing better in aversive conditioning. Our results constitute the first integrative study on how aversive responsiveness affects learning, memory and social

Reappraising social insect behavior through aversive responsiveness and learning.

Directory of Open Access Journals (Sweden)

Edith Roussel

Full Text Available The success of social insects can be in part attributed to their division of labor, which has been explained by a response threshold model. This model posits that individuals differ in their response thresholds to task-associated stimuli, so that individuals with lower thresholds specialize in this task. This model is at odds with findings on honeybee behavior as nectar and pollen foragers exhibit different responsiveness to sucrose, with nectar foragers having higher response thresholds to sucrose concentration. Moreover, it has been suggested that sucrose responsiveness correlates with responsiveness to most if not all other stimuli. If this is the case, explaining task specialization and the origins of division of labor on the basis of differences in response thresholds is difficult.To compare responsiveness to stimuli presenting clear-cut differences in hedonic value and behavioral contexts, we measured appetitive and aversive responsiveness in the same bees in the laboratory. We quantified proboscis extension responses to increasing sucrose concentrations and sting extension responses to electric shocks of increasing voltage. We analyzed the relationship between aversive responsiveness and aversive olfactory conditioning of the sting extension reflex, and determined how this relationship relates to division of labor.Sucrose and shock responsiveness measured in the same bees did not correlate, thus suggesting that they correspond to independent behavioral syndromes, a foraging and a defensive one. Bees which were more responsive to shock learned and memorized better aversive associations. Finally, guards were less responsive than nectar foragers to electric shocks, exhibiting higher tolerance to low voltage shocks. Consequently, foragers, which are more sensitive, were the ones learning and memorizing better in aversive conditioning.Our results constitute the first integrative study on how aversive responsiveness affects learning, memory and

Black Faces, White Spaces: Adjusting Self to Manage Aversive ...

African Journals Online (AJOL)

This article focuses on conversations in which South Africans speak about their experiences of aversive racism in 'raced' spaces. The article interrogates experiences of aversive racism and argues that, for various reasons, racial segregation and less overt forms of racism remain entrenched in South Africa. Presently, those ...

Climate policy: Risk-averse governments

Science.gov (United States)

Harris, Paul G.

2014-04-01

Relative to the scale of the problem, climate policies worldwide have failed. Now research explains why policy innovations are often inadequate, routinely reflecting the aversion of policymakers to the risk of failure.

Endogenous time-varying risk aversion and asset returns.

Science.gov (United States)

Berardi, Michele

2016-01-01

Stylized facts about statistical properties for short horizon returns in financial markets have been identified in the literature, but a satisfactory understanding for their manifestation is yet to be achieved. In this work, we show that a simple asset pricing model with representative agent is able to generate time series of returns that replicate such stylized facts if the risk aversion coefficient is allowed to change endogenously over time in response to unexpected excess returns under evolutionary forces. The same model, under constant risk aversion, would instead generate returns that are essentially Gaussian. We conclude that an endogenous time-varying risk aversion represents a very parsimonious way to make the model match real data on key statistical properties, and therefore deserves careful consideration from economists and practitioners alike.

Neurocognitive development of risk aversion from early childhood to adulthood.

Science.gov (United States)

Paulsen, David J; Carter, R McKell; Platt, Michael L; Huettel, Scott A; Brannon, Elizabeth M

2011-01-01

Human adults tend to avoid risk. In behavioral economic studies, risk aversion is manifest as a preference for sure gains over uncertain gains. However, children tend to be less averse to risk than adults. Given that many of the brain regions supporting decision-making under risk do not reach maturity until late adolescence or beyond it is possible that mature risk-averse behavior may emerge from the development of decision-making circuitry. To explore this hypothesis, we tested 5- to 8-year-old children, 14- to 16-year-old adolescents, and young adults in a risky-decision task during functional magnetic resonance imaging (fMRI) data acquisition. To our knowledge, this is the youngest sample of children in an fMRI decision-making task. We found a number of decision-related brain regions to increase in activation with age during decision-making, including areas associated with contextual memory retrieval and the incorporation of prior outcomes into the current decision-making strategy, e.g., insula, hippocampus, and amygdala. Further, children who were more risk-averse showed increased activation during decision-making in ventromedial prefrontal cortex and ventral striatum. Our findings indicate that the emergence of adult levels of risk aversion co-occurs with the recruitment of regions supporting decision-making under risk, including the integration of prior outcomes into current decision-making behavior. This pattern of results suggests that individual differences in the development of risk aversion may reflect differences in the maturation of these neural processes.

Aversive tension in female adolescents with Anorexia Nervosa: a controlled ecological momentary assessment using smartphones.

Science.gov (United States)

Kolar, David R; Hammerle, Florian; Jenetzky, Ekkehart; Huss, Michael; Bürger, Arne

2016-04-12

Current models of Anorexia Nervosa (AN) emphasize the role of emotion regulation. Aversive tension, described as a state of intense arousal and negative valence, is considered to be a link between emotional events and disordered eating. Recent research focused only on adult patients, and mainly general emotion regulation traits were studied. However, the momentary occurrence of aversive tension, particularly in adolescents with AN, has not been previously studied. 20 female adolescents with AN in outpatient treatment and 20 healthy adolescents aged 12 to 19 years participated in an ecological momentary assessment using their smartphones. Current states of aversive tension and events were assessed hourly for two consecutive weekdays. Mean and maximum values of aversive tension were compared. Multilevel analyses were computed to test the influence of time and reported events on aversive tension. The effect of reported events on subsequent changes of aversive tension in patients with AN were additionally tested in a multilevel model. AN patients showed higher mean and maximum levels of aversive tension. In a multilevel model, reported food intake was associated with higher levels of aversive tension in the AN group, whereas reported school or sport-related events were not linked to specific states of aversive tension. After food intake, subsequent increases of aversive tension were diminished and decreases of aversive tension were induced in adolescents with AN. Aversive tension may play a substantial role in the psychopathology of AN, particular in relation with food intake. Therefore, treatment should consider aversive tension as a possible intervening variable during refeeding. Our findings encourage further research on aversive tension and its link to disordered eating. German register of clinical trials (DRKS): DRKS00005228 (Date of registration: September 2, 2013).

Genotype modulates age-related alterations in sensitivity to the aversive effects of ethanol: an eight inbred strain analysis of conditioned taste aversion.

Science.gov (United States)

Moore, E M; Forrest, R D; Boehm, S L

2013-02-01

Adolescent individuals display altered behavioral sensitivity to ethanol, which may contribute to the increased ethanol consumption seen in this age-group. However, genetics also exert considerable influence on both ethanol intake and sensitivity. Currently there is little research assessing the combined influence of developmental and genetic alcohol sensitivities. Sensitivity to the aversive effects of ethanol using a conditioned taste aversion (CTA) procedure was measured during both adolescence (P30) and adulthood (P75) in eight inbred mouse strains (C57BL/6J, DBA/2J, 129S1/SvImJ, A/J, BALB/cByJ, BTBR T(+) tf/J, C3H/HeJ and FVB/NJ). Adolescent and adult mice were water deprived, and subsequently provided with access to 0.9% (v/v) NaCl solution for 1 h. Immediately following access mice were administered ethanol (0, 1.5, 2.25 and 3 g/kg, ip). This procedure was repeated in 72 h intervals for a total of five CTA trials. Sensitivity to the aversive effects of ethanol was highly dependent upon both strain and age. Within an inbred strain, adolescent animals were consistently less sensitive to the aversive effects of ethanol than their adult counterparts. However, the dose of ethanol required to produce an aversion response differed as a function of both age and strain. © 2012 Blackwell Publishing Ltd and International Behavioural and Neural Genetics Society.

On Loss Aversion, Level-1 Reasoning, and Betting

OpenAIRE

Ido Erev; Sharon Gilat-Yihyie; Davide Marchiori; Doron Sonsino

2013-01-01

Previous research suggests that human reaction to risky opportunities reflects two contradicting biases: Òloss aversion", and Òlimited level of reasoning" that leads to overconfidence. Rejection of attractive gambles is explained by loss aversion, while counterproductive risk seeking is attributed to limited level of reasoning. The current research highlights a shortcoming of this popular (but often implicit) "contradicting biases" assertion. Studies of "negative-sum betting games" reveal hig...

Expressing negative emotions to children: Mothers' aversion sensitivity and children's adjustment.

Science.gov (United States)

Moed, Anat; Dix, Theodore; Anderson, Edward R; Greene, Shannon M

2017-03-01

Research is unclear about when expressing negative emotions to children performs valuable socialization and regulatory functions and when, instead, it undermines children's adjustment. In this study, we isolated 1 kind of negative expression to test the aversion sensitivity hypothesis: that rapid increases in mothers' negativity as a function of increases in the aversiveness of children's behavior are uniquely problematic for children. During multiple assessments of a divorcing sample over 2 years (N = 284), 12-min interactions between mothers and their 4- to 11-year-old children were recorded. Forty-seven observed child behaviors were ranked from low to high aversive. Within-dyad changes demonstrated that mothers' general negativity-their tendency to express negative emotion at high rates-was unrelated to children's adjustment. In contrast, mothers' aversion-focused negativity-their tendency to increase negative emotional expression rapidly as the aversiveness of children's behavior increased-predicted children's poor social competence, poor emotion regulation, and externalizing behavior problems at the next assessment. The findings suggest that negative expression that reflects mothers' affective sensitivity to aversive child behavior may promote interaction patterns and adaptations in children that are particularly likely to place children at risk for adjustment problems. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Neural intrinsic connectivity networks associated with risk aversion in old age.

Science.gov (United States)

Han, S Duke; Boyle, Patricia A; Arfanakis, Konstantinos; Fleischman, Debra A; Yu, Lei; Edmonds, Emily C; Bennett, David A

2012-02-01

Risk aversion is associated with several important real world outcomes. Although the neurobiological correlates of risk aversion have been studied in young persons, little is known of the neurobiological correlates of risk aversion among older persons. Resting-state functional MRI data were collected on 134 non-demented participants of the Rush Memory and Aging Project, a community-based cohort study of aging. Risk aversion was measured using a series of standard questions in which participants were asked to choose between a certain monetary payment ($15) versus a gamble in which they could gain more than $15 or gain nothing, with potential gains varied across questions. Participants determined to be "high" (n=27) and "low" (n=27) in risk aversion were grouped accordingly. Using a spherical seed region of interest in the anterior cingulate cortex, voxel-wise functional connectivity network similarities were observed in bilateral frontal, anterior and posterior cingulate, insula, basal ganglia, temporal, parietal, and thalamic regions. Differences in functional connectivity were observed such that those low in risk aversion had greater connectivity to clusters in the superior, middle, and medial frontal regions, as well as cerebellar, parietal, occipital, and inferior temporal regions. Those high in risk aversion had greater connectivity to clusters in the inferior and orbital frontal, parahippocampal, and insula regions, as well as thalamic, parietal, precentral gyrus, postcentral gyrus, and middle temporal regions. Similarities and differences in functional connectivity patterns may reflect the historical recruitment of specific brain regions as a network in the active processing of risk in older adults. Copyright © 2011 Elsevier B.V. All rights reserved.

Extinction of aversive classically conditioned human sexual response.

Science.gov (United States)

Brom, Mirte; Laan, Ellen; Everaerd, Walter; Spinhoven, Philip; Both, Stephanie

2015-04-01

Research has shown that acquired subjective likes and dislikes are quite resistant to extinction. Moreover, studies on female sexual response demonstrated that diminished genital arousal and positive affect toward erotic stimuli due to aversive classical conditioning did not extinguish during an extinction phase. Possible resistance to extinction of aversive conditioned sexual responses may have important clinical implications. However, resistance to extinction of aversive conditioned human sexual response has not been studied using extensive extinction trials. This article aims to study resistance to extinction of aversive conditioned sexual responses in sexually functional men and women. A differential conditioning experiment was conducted, with two erotic pictures as conditioned stimulus (CSs) and a painful stimulus as unconditioned stimuli (USs). Only one CS (the CS+) was followed by the US during the acquisition phase. Conditioned responses were assessed during the extinction phase. Penile circumference and vaginal pulse amplitude were assessed, and ratings of affective value and subjective sexual arousal were obtained. Also, a stimulus response compatibility task was included to assess automatic approach and avoidance tendencies. Men and women rated the CS+ more negative as compared with the CS-. During the first trials of the extinction phase, vaginal pulse amplitude was lower in response to the CS+ than in response to the CS-, and on the first extinction trial women rated the CS+ as less sexually arousing. Intriguingly, men did not demonstrate attenuated genital and subjective sexual response. Aversive conditioning, by means of painful stimuli, only affects sexual responses in women, whereas it does not in men. Although conditioned sexual likes and dislikes are relatively persistent, conditioned affect eventually does extinguish. © 2014 International Society for Sexual Medicine.

Size doesn't really matter: ambiguity aversion in Ellsberg urns with few balls.

Science.gov (United States)

Pulford, Briony D; Colman, Andrew M

2008-01-01

When attempting to draw a ball of a specified color either from an urn containing 50 red balls and 50 black balls or from an urn containing an unknown ratio of 100 red and black balls, a majority of decision makers prefer the known-risk urn, and this ambiguity aversion effect violates expected utility theory. In an experimental investigation of the effect of urn size on ambiguity aversion, 149 participants showed similar levels of aversion when choosing from urns containing 2, 10, or 100 balls. The occurrence of a substantial and significant ambiguity aversion effect even in the smallest urn suggests that influential theoretical interpretations of ambiguity aversion may need to be reconsidered.

Food Aversions and Cravings during Pregnancy on Yasawa Island, Fiji.

Science.gov (United States)

McKerracher, Luseadra; Collard, Mark; Henrich, Joseph

2016-09-01

Women often experience novel food aversions and cravings during pregnancy. These appetite changes have been hypothesized to work alongside cultural strategies as adaptive responses to the challenges posed by pregnancy (e.g., maternal immune suppression). Here, we report a study that assessed whether data from an indigenous population in Fiji are consistent with the predictions of this hypothesis. We found that aversions focus predominantly on foods expected to exacerbate the challenges of pregnancy. Cravings focus on foods that provide calories and micronutrients while posing few threats to mothers and fetuses. We also found that women who experience aversions to specific foods are more likely to crave foods that meet nutritional needs similar to those provided by the aversive foods. These findings are in line with the predictions of the hypothesis. This adds further weight to the argument that appetite changes may function in parallel with cultural mechanisms to solve pregnancy challenges.

Medial prefrontal cortex dopamine controls the persistent storage of aversive memories

Science.gov (United States)

Gonzalez, María C.; Kramar, Cecilia P.; Tomaiuolo, Micol; Katche, Cynthia; Weisstaub, Noelia; Cammarota, Martín; Medina, Jorge H.

2014-01-01

Medial prefrontal cortex (mPFC) is essential for initial memory processing and expression but its involvement in persistent memory storage has seldom been studied. Using the hippocampus dependent inhibitory avoidance learning task and the hippocampus-independent conditioned taste aversion paradigm together with specific dopamine receptor agonists and antagonists we found that persistence but not formation of long-term aversive memories requires dopamine D1/D5 receptors activation in mPFC immediately after training and, depending on the task, between 6 and 12 h later. Our results indicate that besides its well-known participation in retrieval and early consolidation, mPFC also modulates the endurance of long-lasting aversive memories regardless of whether formation of the aversive mnemonic trace requires the participation of the hippocampus. PMID:25506318

Loss Aversion, Team Relocations, and Major League Expansion

OpenAIRE

Humphreys, Brad; Zhou, Li

2014-01-01

Professional sports teams receive large public subsidies for new facility construction. Empirical research suggests that these subsidies cannot be justified by tangible or intangible economic benefits. We develop a model of bargaining between local governments and teams over subsidies that includes league expansion decisions. The model features loss aversion by fans that captures lost utility when a team leaves a city. The model predicts that teams exploit this loss aversion to extract larger...

Neural markers of loss aversion in resting-state brain activity.

Science.gov (United States)

Canessa, Nicola; Crespi, Chiara; Baud-Bovy, Gabriel; Dodich, Alessandra; Falini, Andrea; Antonellis, Giulia; Cappa, Stefano F

2017-02-01

Neural responses in striatal, limbic and somatosensory brain regions track individual differences in loss aversion, i.e. the higher sensitivity to potential losses compared with equivalent gains in decision-making under risk. The engagement of structures involved in the processing of aversive stimuli and experiences raises a further question, i.e. whether the tendency to avoid losses rather than acquire gains represents a transient fearful overreaction elicited by choice-related information, or rather a stable component of one's own preference function, reflecting a specific pattern of neural activity. We tested the latter hypothesis by assessing in 57 healthy human subjects whether the relationship between behavioral and neural loss aversion holds at rest, i.e. when the BOLD signal is collected during 5minutes of cross-fixation in the absence of an explicit task. Within the resting-state networks highlighted by a spatial group Independent Component Analysis (gICA), we found a significant correlation between strength of activity and behavioral loss aversion in the left ventral striatum and right posterior insula/supramarginal gyrus, i.e. the very same regions displaying a pattern of neural loss aversion during explicit choices. Cross-study analyses confirmed that this correlation holds when voxels identified by gICA are used as regions of interest in task-related activity and vice versa. These results suggest that the individual degree of (neural) loss aversion represents a stable dimension of decision-making, which reflects in specific metrics of intrinsic brain activity at rest possibly modulating cortical excitability at choice. Copyright © 2016 Elsevier Inc. All rights reserved.

The effects of nicotine on ethanol-induced conditioned taste aversions in Long-Evans rats.

Science.gov (United States)

Rinker, Jennifer A; Busse, Gregory D; Roma, Peter G; Chen, Scott A; Barr, Christina S; Riley, Anthony L

2008-04-01

Overall drug acceptability is thought to be a function of the balance between its rewarding and aversive effects, the latter of which is reportedly affected by polydrug use. Given that nicotine and alcohol are commonly co-used, the present experiments sought to assess nicotine's impact on ethanol's aversive effects within a conditioned taste aversion design. Experiment 1 examined various doses of nicotine (0, 0.4, 0.8, 1.2 mg/kg) to determine a behaviorally active dose, and experiment 2 examined various doses of ethanol (0, 0.5, 1.0, 1.5 g/kg) to determine a dose that produced intermediate aversions. Experiment 3 then examined the aversive effects of nicotine (0.8 mg/kg) and ethanol (1.0 g/kg) alone and in combination. Additionally, nicotine's effects on blood alcohol concentrations (BAC) and ethanol-induced hypothermia were examined. Nicotine and ethanol combined produced aversions significantly greater than those produced by either drug alone or the summed aversive effects of the individual compounds. These effects were unrelated to changes in BAC, but nicotine and ethanol combined produced a prolonged hypothermic effect which may contribute to the increased aversions induced by the combination. These data demonstrate that nicotine may interact with ethanol, increasing ethanol's aversive effects. Although the rewarding effects of concurrently administered nicotine and ethanol were not assessed, these data do indicate that the reported high incidence of nicotine and ethanol co-use is unlikely due to reductions in the aversiveness of ethanol with concurrently administered nicotine. It is more likely attributable to nicotine-related changes in ethanol's rewarding effects.

Cognitive function is associated with risk aversion in community-based older persons

Directory of Open Access Journals (Sweden)

Buchman Aron S

2011-09-01

Full Text Available Abstract Background Emerging data from younger and middle-aged persons suggest that cognitive ability is negatively associated with risk aversion, but this association has not been studied among older persons who are at high risk of experiencing loss of cognitive function. Methods Using data from 369 community-dwelling older persons without dementia from the Rush Memory and Aging Project, an ongoing longitudinal epidemiologic study of aging, we examined the correlates of risk aversion and tested the hypothesis that cognition is negatively associated with risk aversion. Global cognition and five specific cognitive abilities were measured via detailed cognitive testing, and risk aversion was measured using standard behavioral economics questions in which participants were asked to choose between a certain monetary payment ($15 versus a gamble in which they could gain more than $15 or gain nothing; potential gamble gains ranged from $21.79 to $151.19 with the gain amounts varied randomly over questions. We first examined the bivariate associations of age, education, sex, income and cognition with risk aversion. Next, we examined the associations between cognition and risk aversion via mixed models adjusted for age, sex, education, and income. Finally, we conducted sensitivity analyses to ensure that our results were not driven by persons with preclinical cognitive impairment. Results In bivariate analyses, sex, education, income and global cognition were associated with risk aversion. However, in a mixed effect model, only sex (estimate = -1.49, standard error (SE = 0.39, p i.e., semantic memory, episodic memory, working memory, and perceptual speed; performance on visuospatial abilities was not. Conclusion A lower level of cognitive ability and female sex are associated with greater risk aversion in advanced age.

Joint Inventory, Pricing, and Advertising Decisions with Surplus and Stockout Loss Aversions

Directory of Open Access Journals (Sweden)

Bing-Bing Cao

2016-01-01

Full Text Available The newsvendor models considering decision-makers’ behavioral factors remain a fruitful research area in operation management field in past decade. In this paper, we further extend the current literatures to look into joint inventory, pricing, and advertising decisions considering loss aversion effects under the newsvendor setting. The purpose is to explore how the loss aversions affect the optimal policy of order quantity, price, and advertising effort level. We present an integrated utility model to measure both economic payoff and loss aversion utility of the newsvendor, where surplus loss aversion and stockout loss aversion are first separately defined and quantified. Then, we analyze the optimal solution conditions of the integrated model under exogenous and endogenous price cases, respectively. Under exogenous price case, we find that the uniquely optimal policy exists and is presented in the closed form. Under endogenous price case, the optimal policy is determined under mild conditions; we also provide the solutions when order quantity factor or advertising effort level is fixed in this case. In addition, the sensitivity analysis shows that the loss aversions affect the optimal decisions of order quantity, price, and advertising effort level in a systematic way.

Economic decision biases and fundamental motivations: how mating and self-protection alter loss aversion.

Science.gov (United States)

Li, Yexin Jessica; Kenrick, Douglas T; Griskevicius, Vladas; Neuberg, Steven L

2012-03-01

Much research shows that people are loss averse, meaning that they weigh losses more heavily than gains. Drawing on an evolutionary perspective, we propose that although loss aversion might have been adaptive for solving challenges in the domain of self-protection, this may not be true for men in the domain of mating. Three experiments examine how loss aversion is influenced by mating and self-protection motives. Findings reveal that mating motives selectively erased loss aversion in men. In contrast, self-protective motives led both men and women to become more loss averse. Overall, loss aversion appears to be sensitive to evolutionarily important motives, suggesting that it may be a domain-specific bias operating according to an adaptive logic of recurring threats and opportunities in different evolutionary domains.

Ambiguity aversion is not universal

NARCIS (Netherlands)

Kocher, M.G.; Lahno, Amrei; Trautmann, Stefan

Assuming universal ambiguity aversion, an extensive theoretical literature studies how ambiguity can account for market anomalies from the perspective of expected utility-based theories. We provide a systematic experimental assessment of ambiguity attitudes in different likelihood ranges, and in the

Human capital and risk aversion in relational incentive contracts

International Nuclear Information System (INIS)

Kvaloey, Ola

2003-01-01

This paper examines a self-enforced relational incentive contract between a risk neutral principal and a risk averse agent where the agent's human capital is essential in ex post realization of values. I analyse the effect of outside options on the optimal bonus level, showing how the presence of ex post outside options may impede desirable degrees of performance pay. The effect of risk aversion and incentive responsiveness is analysed by allowing for linear contracts. I show that the first order effect of these parameters are the same as in verifiable contracts, but second order effects show that the optimal bonus level's sensitivity to risk aversion and incentive responsiveness increases with the discount factor. The analysis has interesting implications on firm boundaries and specificity choices. (author)

The risks of risk aversion in drug regulation.

Science.gov (United States)

Eichler, Hans-Georg; Bloechl-Daum, Brigitte; Brasseur, Daniel; Breckenridge, Alasdair; Leufkens, Hubert; Raine, June; Salmonson, Tomas; Schneider, Christian K; Rasi, Guido

2013-12-01

Drugs are approved by regulatory agencies on the basis of their assessment of whether the available evidence indicates that the benefits of the drug outweigh its risks. In recent years, regulatory agencies have been criticized both for being overly tolerant of risks or being excessively risk-averse, which reflects the challenge in determining an appropriate balance between benefit and risk with the limited data that is typically available before drug approval. The negative consequences of regulatory tolerance in allowing drugs onto the market that turn out to be unsafe are obvious, but the potential for adverse effects on public health owing to the absence of new drugs because of regulatory risk-aversion is less apparent. Here, we discuss the consequences of regulatory risk-aversion for public health and suggest what might be done to best align acceptance of risk and uncertainty by regulators with the interests of public health.

Patient risk perceptions for carotid endarterectomy: which patients are strongly averse to surgery?

Science.gov (United States)

Bosworth, Hayden B; Stechuchak, Karen M; Grambow, Steven C; Oddone, Eugene Z

2004-07-01

Patient risk perception for surgery may be central to their willingness to undergo surgery. This study examined potential factors associated with patient aversion of surgery. This is a secondary data analysis of a prospective cohort study that examined patients referred for evaluation of carotid artery stenosis at five Veterans Affairs Medical Centers. The study collected demographic, clinical, and psychosocial information related to surgery. This analysis focused on patient response to a question assessing their aversion to surgery. Among the 1065 individuals, at the time of evaluation for carotid endarterectomy (CEA), 66% of patients had no symptoms, 16% had a transient ischemic attack, and 18% had stroke. Twelve percent of patients referred for CEA evaluation were averse to surgery. In adjusted analyses, increased age, black race, no previous surgery, lower level of chance locus of control, less trust of physicians, and less social support were significantly related to greater likelihood of surgery aversion among individuals referred for CEA evaluation. Patient degree of medical comorbidity and a validated measure of preoperative risk score were not associated with increased aversion to surgery. In previous work, aversion to CEA was associated with lack of receipt of CEA even after accounting for patient clinical appropriateness for surgery. We identified important patient characteristics associated with aversion to CEA. Interventions designed to assist patient decision making should focus on these more complex factors related to CEA aversion rather than the simple explanation of clinical usefulness.

Risk Aversion is Associated with Decision Making among Community-Based Older Persons.

Science.gov (United States)

Boyle, Patricia A; Yu, Lei; Buchman, Aron S; Bennett, David A

2012-01-01

Risk aversion is associated with many important decisions among younger and middle aged persons, but the association of risk aversion with decision making has not been well studied among older persons who face some of the most significant decisions of their lives. Using data from 606 community-dwelling older persons without dementia from the Rush Memory and Aging Project, an ongoing longitudinal epidemiologic study of aging, we examined the association of risk aversion with decision making. Risk aversion was measured using standard behavioral economics questions in which participants were asked to choose between a certain monetary payment ($15) versus a gamble in which they could gain more than $15 or gain nothing; potential gamble gains ranged from $20 to $300 with the gain amounts varied randomly over questions. Decision making was measured using a 12 item version of the Decision Making Competence Assessment Tool. In a linear regression model adjusted for age, sex, education, and income, greater risk aversion was associated with poorer decision making [estimate = -1.03, standard error (SE) = 0.35, p = 0.003]. Subsequent analyses showed that the association of risk aversion with decision making persisted after adjustment for global cognitive function as well as executive and non-executive cognitive abilities. Similar to findings from studies of younger persons, risk aversion is associated with poorer decision making among older persons who face a myriad of complex and influential decisions.

Loss aversion and hypoxia: less loss aversion in oxygen-depleted environment.

Science.gov (United States)

Pighin, Stefania; Bonini, Nicolao; Savadori, Lucia; Hadjichristidis, Constantinos; Schena, Federico

2014-03-01

Hypoxia, the deprivation of adequate oxygen supply, constitutes a direct threat to survival by disrupting cardiovascular or respiratory homeostasis and eliciting a respiratory distress. Although hypoxia has been shown to increase brain vulnerability and impair basic cognitive functions, only one study has examined its effect on decision-making. The present study examined the effect of mild hypoxia on individual's loss aversion, that is, the tendency to be more affected by losses than equal sized gains. A sample of 26 participants were asked to either accept or reject a series of mixed gambles once in an oxygen-depleted environment (14.1% oxygen concentration) and once in a normoxic environment (20.9% oxygen concentration). Each gamble involved a 50-50 chance of winning or losing specified amounts of money. Mild hypoxia decreased loss aversion: on average in the normoxic condition participants accepted gambles if the gain was at least 2.4 times as large as the loss, whereas in the oxygen-depleted condition participants accepted gambles if the gain was at least 1.7 times as large as the loss. Mild hypoxia may push individuals to be less cautious in daily decisions that involve a trade-off between a gain and a loss.

Loss Aversion and Time-Differentiated Electricity Pricing

Energy Technology Data Exchange (ETDEWEB)

Spurlock, C. Anna [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2015-06-01

I develop a model of loss aversion over electricity expenditure, from which I derive testable predictions for household electricity consumption while on combination time-of-use (TOU) and critical peak pricing (CPP) plans. Testing these predictions results in evidence consistent with loss aversion: (1) spillover effects - positive expenditure shocks resulted in significantly more peak consumption reduction for several weeks thereafter; and (2) clustering - disproportionate probability of consuming such that expenditure would be equal between the TOUCPP or standard flat-rate pricing structures. This behavior is inconsistent with a purely neoclassical utility model, and has important implications for application of time-differentiated electricity pricing.

The effects of cocaine, alcohol and cocaine/alcohol combinations in conditioned taste aversion learning.

Science.gov (United States)

Busse, Gregory D; Verendeev, Andrey; Jones, Jermaine; Riley, Anthony L

2005-09-01

We have recently reported that alcohol attenuates cocaine place preferences. Although the basis for this effect is unknown, alcohol may attenuate cocaine reward by potentiating its aversive effects. To examine this possibility, these experiments assessed the effects of alcohol on cocaine-induced taste aversions under conditions similar to those that resulted in attenuated place preferences. Specifically, Experiments 1 and 2 assessed the effects of alcohol (0.5 g/kg) on taste aversions induced by 20, 30 and 40 mg/kg cocaine. Experiment 3 examined the role of intertrial interval in the effects of alcohol (0.5 g/kg) on cocaine (30 mg/kg) taste aversions. In Experiments 1 and 2, cocaine was effective at conditioning aversions. Alcohol produced no measurable effect. Combining cocaine and alcohol produced no greater aversion than cocaine alone (and, in fact, weakened aversions at the lowest dose of cocaine). In Experiment 3, varying the intertrial interval from 3 days (as in the case of Experiments 1 and 2) to 1 day (a procedure identical to that in which alcohol attenuated cocaine place preferences) resulted in significant alcohol- and cocaine-induced taste aversions. Nonetheless, alcohol remained ineffective in potentiating cocaine aversions. Thus, under these conditions alcohol does not potentiate cocaine's aversiveness. These results were discussed in terms of their implication for the effects of alcohol on cocaine-induced place preferences. Further, the effects of alcohol on place preferences conditioned by cocaine were discussed in relation to other assessments of the effects of alcohol on the affective properties of cocaine and the implications of these interactions for alcohol and cocaine co-use.

Appetitive and aversive visual learning in freely moving Drosophila

Directory of Open Access Journals (Sweden)

Christopher Schnaitmann

2010-03-01

Full Text Available To compare appetitive and aversive visual memories of the fruit fly Drosophila melanogaster, we developed a new paradigm for classical conditioning. Adult flies are trained en masse to differentially associate one of two visual conditioned stimuli (blue and green light as conditioned stimuli or CS with an appetitive or aversive chemical substance (unconditioned stimulus or US. In a test phase, flies are given a choice between the paired and the unpaired visual stimuli. Associative memory is measured based on altered visual preference in the test. If a group of flies has, for example, received a sugar reward with green light, they show a significantly higher preference for the green stimulus during the test than another group of flies having received the same reward with blue light. We demonstrate critical parameters for the formation of visual appetitive memory, such as training repetition, order of reinforcement, starvation, and individual conditioning. Furthermore, we show that formic acid can act as an aversive chemical reinforcer, yielding weak, yet significant, aversive memory. These results provide a basis for future investigations into the cellular and molecular mechanisms underlying visual memory and perception in Drosophila.

Risk Aversion and Public Reporting. Part 2: Mitigation Strategies.

Science.gov (United States)

Shahian, David M; Jacobs, Jeffrey P; Badhwar, Vinay; D'Agostino, Richard S; Bavaria, Joseph E; Prager, Richard L

2017-12-01

Part 1 of this review summarizes the consequences of risk aversion and the observational studies and surveys relevant to this phenomenon, almost all of which are derived from cardiac surgery and interventional cardiology. In Part 2, we describe the root cause of risk aversion-the belief by providers that current risk adjustment is inadequate to account for the severity of their highest-risk patients, thereby prejudicing their publicly reported performance scores. Evidence supporting the robustness of current risk adjustment is presented, as well as nine potential strategies to further mitigate risk aversion: optimization of data source, risk models, and performance measures; exclusion of high-risk patients; exclusion of non-procedure-related end points; separate reporting of high-risk patients; reporting by condition or diagnosis rather than by procedures; reporting at the hospital or program level rather than the physician level; collaborative, cross-disciplinary decision making; active surveillance for risk aversion; and improved stakeholder education. Of these, the first is most desirable, widely applicable, and resistant to gaming. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Role of IL-4 in aversion induced by food allergy in mice.

Science.gov (United States)

Dourado, Luana Pereira Antunes; Saldanha, Janaína Cláudia da Silva; Gargiulo, Daniela Longo; Noviello, Maria de Lourdes Meirelles; Brant, Cláudia Caldeira; Reis, Maria Letícia Costa; Souza, Raphaela Mendes Fernandes de; Faria, Ana Maria Caetano; Souza, Danielle da Glória de; Cara, Denise Carmona

2010-01-01

To ascertain the role of IL-4 in aversion to antigen induced by food allergy, wild type and IL-4 deficient BALB/c mice were sensitized with ovalbumin and challenged orally with egg white. Sensitized wild type mice had increased production of IL-4 by spleen and mesenteric lymph node cells in vitro, higher levels of serum anti-ovalbumin IgE and IgG1, aversion to ingestion of the antigen and loss of body weight after continuous oral challenge. Intestinal changes in wild type sensitized mice included eosinophil infiltration and increased mucus production. The IL-4 deficiency impaired the development of food allergy and the aversion to antigen, suggesting the involvement of the antigen specific antibodies. When IL-4 deficient mice received serum from sensitized wild type donors, the aversion was restored. These results indicate that production of IL-4 and specific IgE/IgG1 antibodies correlate with aversion to antigen induced by food allergy in mice. Copyright 2009 Elsevier Inc. All rights reserved.

Risk Aversion and Job Mobility

NARCIS (Netherlands)

van Huizen, T.M.; Alessie, Rob

2016-01-01

Job mobility is inherently risky as workers have limited ex ante information about the quality of outside jobs. Using a large longitudinal Dutch dataset, which includes data on risk preferences elicited through (incentivized) experiments, we examine the relation between risk aversion and job

The Neural Foundations of Reaction and Action in Aversive Motivation.

Science.gov (United States)

Campese, Vincent D; Sears, Robert M; Moscarello, Justin M; Diaz-Mataix, Lorenzo; Cain, Christopher K; LeDoux, Joseph E

2016-01-01

Much of the early research in aversive learning concerned motivation and reinforcement in avoidance conditioning and related paradigms. When the field transitioned toward the focus on Pavlovian threat conditioning in isolation, this paved the way for the clear understanding of the psychological principles and neural and molecular mechanisms responsible for this type of learning and memory that has unfolded over recent decades. Currently, avoidance conditioning is being revisited, and with what has been learned about associative aversive learning, rapid progress is being made. We review, below, the literature on the neural substrates critical for learning in instrumental active avoidance tasks and conditioned aversive motivation.

Risk Aversion and Sorting into Public Sector Employment

OpenAIRE

Pfeifer, Christian

2008-01-01

This research note uses two German data sets – the large-scale German Socio-Economic Panel and unique data from own student questionnaires – to analyse the relationship between risk aversion and the choice for public sector employment. Main results are: (1) more risk averse individuals sort into public sector employment, (2) the impact of career specific and unemployment risk attitudes is larger than the impact of general risk attitudes, and (3) risk taking is rewarded with higher wages in th...

A Survey Data Response to the Teaching of Utility Curves and Risk Aversion

Science.gov (United States)

Hobbs, Jeffrey; Sharma, Vivek

2011-01-01

In many finance and economics courses as well as in practice, the concept of risk aversion is reduced to the standard deviation of returns, whereby risk-averse investors prefer to minimize their portfolios' standard deviations. In reality, the concept of risk aversion is richer and more interesting than this, and can easily be conveyed through…

Acquisition of lithium chloride- and radiation-induced taste aversions in hypophysectomized rats

International Nuclear Information System (INIS)

Rabin, B.M.; Hunt, W.A.; Lee, J.

1983-01-01

The effects of hypophysectomy on the acquisition of conditioned taste aversions following injection of lithium chloride and following exposure to ionizing radiation were studied using a two-bottle preference test. Hypophysectomy did not disrupt the acquisition of a taste aversion following either treatment. The results are interpreted as: (a) suggesting that pituitary/adrenal hormones do not mediate the acquisition of a conditioned taste aversion following injections of lithium chloride or following exposure to ionizing radiation in a two-bottle preference test, and (b) consistent with other research suggesting that the involvement of pituitary/adrenal hormones in taste aversion learning may be related to the conflict induced by using a one-bottle test and not to the learning itself

The Neural Basis of Aversive Pavlovian Guidance during Planning.

Science.gov (United States)

Lally, Níall; Huys, Quentin J M; Eshel, Neir; Faulkner, Paul; Dayan, Peter; Roiser, Jonathan P

2017-10-18

Important real-world decisions are often arduous as they frequently involve sequences of choices, with initial selections affecting future options. Evaluating every possible combination of choices is computationally intractable, particularly for longer multistep decisions. Therefore, humans frequently use heuristics to reduce the complexity of decisions. We recently used a goal-directed planning task to demonstrate the profound behavioral influence and ubiquity of one such shortcut, namely aversive pruning, a reflexive Pavlovian process that involves neglecting parts of the decision space residing beyond salient negative outcomes. However, how the brain implements this important decision heuristic and what underlies individual differences have hitherto remained unanswered. Therefore, we administered an adapted version of the same planning task to healthy male and female volunteers undergoing functional magnetic resonance imaging (fMRI) to determine the neural basis of aversive pruning. Through both computational and standard categorical fMRI analyses, we show that when planning was influenced by aversive pruning, the subgenual cingulate cortex was robustly recruited. This neural signature was distinct from those associated with general planning and valuation, two fundamental cognitive components elicited by our task but which are complementary to aversive pruning. Furthermore, we found that individual variation in levels of aversive pruning was associated with the responses of insula and dorsolateral prefrontal cortices to the receipt of large monetary losses, and also with subclinical levels of anxiety. In summary, our data reveal the neural signatures of an important reflexive Pavlovian process that shapes goal-directed evaluations and thereby determines the outcome of high-level sequential cognitive processes. SIGNIFICANCE STATEMENT Multistep decisions are complex because initial choices constrain future options. Evaluating every path for long decision sequences

The Neural Basis of Aversive Pavlovian Guidance during Planning

Science.gov (United States)

Faulkner, Paul

2017-01-01

Important real-world decisions are often arduous as they frequently involve sequences of choices, with initial selections affecting future options. Evaluating every possible combination of choices is computationally intractable, particularly for longer multistep decisions. Therefore, humans frequently use heuristics to reduce the complexity of decisions. We recently used a goal-directed planning task to demonstrate the profound behavioral influence and ubiquity of one such shortcut, namely aversive pruning, a reflexive Pavlovian process that involves neglecting parts of the decision space residing beyond salient negative outcomes. However, how the brain implements this important decision heuristic and what underlies individual differences have hitherto remained unanswered. Therefore, we administered an adapted version of the same planning task to healthy male and female volunteers undergoing functional magnetic resonance imaging (fMRI) to determine the neural basis of aversive pruning. Through both computational and standard categorical fMRI analyses, we show that when planning was influenced by aversive pruning, the subgenual cingulate cortex was robustly recruited. This neural signature was distinct from those associated with general planning and valuation, two fundamental cognitive components elicited by our task but which are complementary to aversive pruning. Furthermore, we found that individual variation in levels of aversive pruning was associated with the responses of insula and dorsolateral prefrontal cortices to the receipt of large monetary losses, and also with subclinical levels of anxiety. In summary, our data reveal the neural signatures of an important reflexive Pavlovian process that shapes goal-directed evaluations and thereby determines the outcome of high-level sequential cognitive processes. SIGNIFICANCE STATEMENT Multistep decisions are complex because initial choices constrain future options. Evaluating every path for long decision sequences

Methods for measuring risk-aversion: problems and solutions

International Nuclear Information System (INIS)

Thomas, P J

2013-01-01

Risk-aversion is a fundamental parameter determining how humans act when required to operate in situations of risk. Its general applicability has been discussed in a companion presentation, and this paper examines methods that have been used in the past to measure it and their attendant problems. It needs to be borne in mind that risk-aversion varies with the size of the possible loss, growing strongly as the possible loss becomes comparable with the decision maker's assets. Hence measuring risk-aversion when the potential loss or gain is small will produce values close to the risk-neutral value of zero, irrespective of who the decision maker is. It will also be shown how the generally accepted practice of basing a measurement on the results of a three-term Taylor series will estimate a limiting value, minimum or maximum, rather than the value utilised in the decision. A solution is to match the correct utility function to the results instead

Methods for measuring risk-aversion: problems and solutions

Science.gov (United States)

Thomas, P. J.

2013-09-01

Risk-aversion is a fundamental parameter determining how humans act when required to operate in situations of risk. Its general applicability has been discussed in a companion presentation, and this paper examines methods that have been used in the past to measure it and their attendant problems. It needs to be borne in mind that risk-aversion varies with the size of the possible loss, growing strongly as the possible loss becomes comparable with the decision maker's assets. Hence measuring risk-aversion when the potential loss or gain is small will produce values close to the risk-neutral value of zero, irrespective of who the decision maker is. It will also be shown how the generally accepted practice of basing a measurement on the results of a three-term Taylor series will estimate a limiting value, minimum or maximum, rather than the value utilised in the decision. A solution is to match the correct utility function to the results instead.

Determinants of Propranolol's Selective Effect on Loss Aversion.

Science.gov (United States)

Sokol-Hessner, Peter; Lackovic, Sandra F; Tobe, Russell H; Camerer, Colin F; Leventhal, Bennett L; Phelps, Elizabeth A

2015-07-01

Research on emotion and decision making has suggested that arousal mediates risky decisions, but several distinct and often confounded processes drive such choices. We used econometric modeling to separate and quantify the unique contributions of loss aversion, risk attitudes, and choice consistency to risky decision making. We administered the beta-blocker propranolol in a double-blind, placebo-controlled within-subjects study, targeting the neurohormonal basis of physiological arousal. Matching our intervention's pharmacological specificity with a quantitative model delineating decision-making components allowed us to identify the causal relationships between arousal and decision making that do and do not exist. Propranolol selectively reduced loss aversion in a baseline- and dose-dependent manner (i.e., as a function of initial loss aversion and body mass index), and did not affect risk attitudes or choice consistency. These findings provide evidence for a specific, modulatory, and causal relationship between precise components of emotion and risky decision making. © The Author(s) 2015.

Managing Risk Aversion for Low-Carbon Supply Chains with Emission Abatement Outsourcing.

Science.gov (United States)

Wang, Qinpeng; He, Longfei

2018-02-21

Reducing carbon emissions, including emission abatement outsourcing at the supply-chain level, is becoming a significant but challenging problem in practice. Confronting this challenge, we therefore break down the practice to focus on a low-carbon supply chain consisting of one supplier, one manufacturer and one third-party emission-reducing contractor. The contractor offers a carbon reduction service to the manufacturer. In view of the increasing proportion of Greenhouse Gases (GHG) emissions and absence of carbon reduction policies in developing countries, we adopt the prospect of consumers' low-carbon preferences to capture the demand sensitivity on carbon emission. By exploiting the Mean-Variance (MV) model, we develop a supply chain game model considering risk aversion. Comparing the supply chain performances of the cases under risk neutrality and risk aversion, we investigate the impact of the risk aversion of the supplier and the manufacturer on the low-carbon supply chain performances, respectively. We show that the risk aversion of chain members will not influence the relationship underlain by the profit-sharing contract between the manufacturer and contractor, whereas they may extend the supplier's concerning range. Although the manufacturer's risk aversion has a positive impact on the wholesale price, interestingly, the supplier's impact on the wholesale price is negative. Furthermore, we propose a contract to coordinate the risk-averse low-carbon supply chain by tuning the aversion levels of the supplier and the manufacturer, respectively. Through numerical study, we draw on managerial insights for industrial practitioners to adopt a low carbon strategy potentially by managing the risk attitudes along the supply chain channel.

Effects of loss aversion on neural responses to loss outcomes: An event-related potential study.

Science.gov (United States)

Kokmotou, Katerina; Cook, Stephanie; Xie, Yuxin; Wright, Hazel; Soto, Vicente; Fallon, Nicholas; Giesbrecht, Timo; Pantelous, Athanasios; Stancak, Andrej

2017-05-01

Loss aversion is the tendency to prefer avoiding losses over acquiring gains of the same amount. To shed light on the spatio-temporal processes underlying loss aversion, we analysed the associations between individual loss aversion and electrophysiological responses to loss and gain outcomes in a monetary gamble task. Electroencephalographic feedback-related negativity (FRN) was computed in 29 healthy participants as the difference in electrical potentials between losses and gains. Loss aversion was evaluated using non-linear parametric fitting of choices in a separate gamble task. Loss aversion correlated positively with FRN amplitude (233-263ms) at electrodes covering the lower face. Feedback related potentials were modelled by five equivalent source dipoles. From these dipoles, stronger activity in a source located in the orbitofrontal cortex was associated with loss aversion. The results suggest that loss aversion implemented during risky decision making is related to a valuation process in the orbitofrontal cortex, which manifests during learning choice outcomes. Copyright © 2017. Published by Elsevier B.V.

Different components of conditioned food aversion memory.

Science.gov (United States)

Nikitin, Vladimir P; Solntseva, Svetlana V; Kozyrev, Sergey A; Nikitin, Pavel V; Shevelkin, Alexey V

2016-07-01

Memory reconsolidation processes and protein kinase Mzeta (PKMzeta) activity in memory maintenance and reorganization are poorly understood. Therefore, we examined memory reconsolidation and PKMzeta activity during the maintenance and reorganization of a conditioned food aversion memory among snails. These processes were specifically evaluated after administration of a serotonin receptor antagonist (methiothepin), NMDA glutamate receptor antagonist (MK-801), protein synthesis inhibitor (cycloheximide; CYH), or PKMzeta inhibitor (zeta inhibitory peptide; ZIP) either 2 or 10 days after aversion training. Two days post-training, injections of MK-801 or CYH, combined with a conditioned stimulus reminder, caused amnesia development, and a second training 11 days after this induction did not lead to long-term memory formation. Interestingly, MK-801 or CYH injections and the reminder 10 days after training did not affect memory retrieval. Methiothepin and the reminder, or ZIP without the reminder, at 2 and 10 days after training led to memory impairment, while a second training 11 days after amnesia induction resulted in memory formation. These results suggest that the maintenance of a conditioned food aversion involves two different components with variable dynamics. One component could be characterized by memory strengthening over time and involve N-methyl-D-aspartate receptors and protein synthesis reconsolidation at early, but not late, training stages. The other memory component could involve serotonin-dependent reconsolidation and Mzeta-like kinase activity at both early and late stages after learning. Deficiencies within these two components led to various forms of memory impairment, which differed in terms of the formation of a conditioned food aversion during the second training. Copyright © 2016 Elsevier B.V. All rights reserved.

On Loss Aversion, Level-1 Reasoning, and Betting

DEFF Research Database (Denmark)

Erev, Ido; Gilat-Yihyie, Sharon; Marchiori, Davide

2014-01-01

Previous research suggests that human reaction to risky opportunities reflects two contradicting biases: “loss aversion”, and “limited level of reasoning” that leads to overconfidence. Rejection of attractive gambles is explained by loss aversion, while counterproductive risk seeking is attributed...... to limited level of reasoning. The current research highlights a shortcoming of this popular (but often implicit) “contradicting biases” assertion. Studies of “negative-sum betting games” reveal high rate of counterproductive betting even when limited level of reasoning and loss aversion imply no betting...

Aversive reinforcement improves visual discrimination learning in free-flying honeybees.

Directory of Open Access Journals (Sweden)

Aurore Avarguès-Weber

Full Text Available BACKGROUND: Learning and perception of visual stimuli by free-flying honeybees has been shown to vary dramatically depending on the way insects are trained. Fine color discrimination is achieved when both a target and a distractor are present during training (differential conditioning, whilst if the same target is learnt in isolation (absolute conditioning, discrimination is coarse and limited to perceptually dissimilar alternatives. Another way to potentially enhance discrimination is to increase the penalty associated with the distractor. Here we studied whether coupling the distractor with a highly concentrated quinine solution improves color discrimination of both similar and dissimilar colors by free-flying honeybees. As we assumed that quinine acts as an aversive stimulus, we analyzed whether aversion, if any, is based on an aversive sensory input at the gustatory level or on a post-ingestional malaise following quinine feeding. METHODOLOGY/PRINCIPAL FINDINGS: We show that the presence of a highly concentrated quinine solution (60 mM acts as an aversive reinforcer promoting rejection of the target associated with it, and improving discrimination of perceptually similar stimuli but not of dissimilar stimuli. Free-flying bees did not use remote cues to detect the presence of quinine solution; the aversive effect exerted by this substance was mediated via a gustatory input, i.e. via a distasteful sensory experience, rather than via a post-ingestional malaise. CONCLUSION: The present study supports the hypothesis that aversion conditioning is important for understanding how and what animals perceive and learn. By using this form of conditioning coupled with appetitive conditioning in the framework of a differential conditioning procedure, it is possible to uncover discrimination capabilities that may remain otherwise unsuspected. We show, therefore, that visual discrimination is not an absolute phenomenon but can be modulated by experience.

Increased Loss Aversion in Unmedicated Patients with Obsessive–Compulsive Disorder

Directory of Open Access Journals (Sweden)

Kamila E. Sip

2018-01-01

Full Text Available IntroductionObsessive–compulsive disorder (OCD patients show abnormalities in decision-making and, clinically, appear to show heightened sensitivity to potential negative outcomes. Despite the importance of these cognitive processes in OCD, few studies have examined the disorder within an economic decision-making framework. Here, we investigated loss aversion, a key construct in the prospect theory that describes the tendency for individuals to be more sensitive to potential losses than gains when making decisions.MethodsAcross two study sites, groups of unmedicated OCD patients (n = 14, medicated OCD patients (n = 29, and healthy controls (n = 34 accepted or rejected a series of 50/50 gambles containing varying loss/gain values. Loss aversion was calculated as the ratio of the likelihood of rejecting a gamble with increasing potential losses to the likelihood of accepting a gamble with increasing potential gains. Decision times to accept or reject were also examined and correlated with loss aversion.ResultsUnmedicated OCD patients exhibited significantly more loss aversion compared to medicated OCD or controls, an effect that was replicated across both sites and remained significant even after controlling for OCD symptom severity, trait anxiety, and sex. Post hoc analyses further indicated that unmedicated patients’ increased likelihood to reject a gamble as its loss value increased could not be explained solely by greater risk aversion among patients. Unmedicated patients were also slower to accept than reject gambles, effects that were not found in the other two groups. Loss aversion was correlated with decision times in unmedicated patients but not in the other two groups.DiscussionThese data identify abnormalities of decision-making in a subgroup of OCD patients not taking psychotropic medication. The findings help elucidate the cognitive mechanisms of the disorder and suggest that future treatments could aim to target

Increased Loss Aversion in Unmedicated Patients with Obsessive-Compulsive Disorder.

Science.gov (United States)

Sip, Kamila E; Gonzalez, Richard; Taylor, Stephan F; Stern, Emily R

2017-01-01

Obsessive-compulsive disorder (OCD) patients show abnormalities in decision-making and, clinically, appear to show heightened sensitivity to potential negative outcomes. Despite the importance of these cognitive processes in OCD, few studies have examined the disorder within an economic decision-making framework. Here, we investigated loss aversion, a key construct in the prospect theory that describes the tendency for individuals to be more sensitive to potential losses than gains when making decisions. Across two study sites, groups of unmedicated OCD patients ( n  = 14), medicated OCD patients ( n  = 29), and healthy controls ( n  = 34) accepted or rejected a series of 50/50 gambles containing varying loss/gain values. Loss aversion was calculated as the ratio of the likelihood of rejecting a gamble with increasing potential losses to the likelihood of accepting a gamble with increasing potential gains. Decision times to accept or reject were also examined and correlated with loss aversion. Unmedicated OCD patients exhibited significantly more loss aversion compared to medicated OCD or controls, an effect that was replicated across both sites and remained significant even after controlling for OCD symptom severity, trait anxiety, and sex. Post hoc analyses further indicated that unmedicated patients' increased likelihood to reject a gamble as its loss value increased could not be explained solely by greater risk aversion among patients. Unmedicated patients were also slower to accept than reject gambles, effects that were not found in the other two groups. Loss aversion was correlated with decision times in unmedicated patients but not in the other two groups. These data identify abnormalities of decision-making in a subgroup of OCD patients not taking psychotropic medication. The findings help elucidate the cognitive mechanisms of the disorder and suggest that future treatments could aim to target abnormalities of loss/gain processing during

Effects of pharmacological manipulation of the kappa opioid receptors on the aversive effects of nicotine.

Science.gov (United States)

Ward, Melissa; Norman, Haval; D'Souza, Manoranjan S

2018-02-15

Nicotine, an addictive component of tobacco smoke, produces both rewarding and aversive effects. Increasing the aversive effects of nicotine may help in promoting smoking cessation. However, neural targets mediating the aversive effects of nicotine have not been fully identified. In this study, we evaluated the role of kappa opioid receptors (KORs) in the aversive effects of nicotine (0.4 mg/kg, base; s.c.) using the nicotine-induced conditioned taste aversion (CTA) model in Wistar rats. The KORs were activated using the selective KOR agonist (±)U-50,488H (0, 0.03, 0.15 & 0.3mg/kg; s.c.) and inhibited using the KOR antagonist nor-binaltorphimine (nor-BNI; 0, 15 & 30mg/kg; s.c.) in separate groups of rats using a between-subjects design. Pretreatment with the KOR agonist (±)U-50,488H (0.3mg/kg) significantly increased aversion for the nicotine-associated solution. Additionally, (±)U-50,488H (0.3mg/kg) on its own induced aversion to the flavored solution associated with it even in the absence of nicotine, suggesting that the KOR agonist induced increase in nicotine-induced aversion was an additive effect. Interestingly, administration of the KOR antagonist nor-BNI (30mg/kg) prior to conditioning with nicotine/saline, but not after conditioning with nicotine/saline, attenuated nicotine-induced aversive effects compared to saline controls. Taken together, these data suggest a role for KORs in the aversive effects of nicotine. Copyright © 2017 Elsevier B.V. All rights reserved.

Aversive Stimulation -- Criteria for Application.

Science.gov (United States)

O'Donnell, Patrick A.; Ohlson, Glenn A.

Criteria for applying aversive stimulation with severely handicapped children are examined, and practical and ethical issues are considered. Factors seen to influence punishment outcomes include timing, intensity, and schedule of reinforcement. Suggested is the need for further research on the comparative effectiveness of positive and negative…

Estimation of Esfarayen Farmers Risk Aversion Coefficient and Its Influencing Factors (Nonparametric Approach

Directory of Open Access Journals (Sweden)

Z. Nematollahi

2016-03-01

Full Text Available Introduction: Due to existence of the risk and uncertainty in agriculture, risk management is crucial for management in agriculture. Therefore the present study was designed to determine the risk aversion coefficient for Esfarayens farmers. Materials and Methods: The following approaches have been utilized to assess risk attitudes: (1 direct elicitation of utility functions, (2 experimental procedures in which individuals are presented with hypothetical questionnaires regarding risky alternatives with or without real payments and (3: Inference from observation of economic behavior. In this paper, we focused on approach (3: inference from observation of economic behavior, based on this assumption of existence of the relationship between the actual behavior of a decision maker and the behavior predicted from empirically specified models. A new non-parametric method and the QP method were used to calculate the coefficient of risk aversion. We maximized the decision maker expected utility with the E-V formulation (Freund, 1956. Ideally, in constructing a QP model, the variance-covariance matrix should be formed for each individual farmer. For this purpose, a sample of 100 farmers was selected using random sampling and their data about 14 products of years 2008- 2012 were assembled. The lowlands of Esfarayen were used since within this area, production possibilities are rather homogeneous. Results and Discussion: The results of this study showed that there was low correlation between some of the activities, which implies opportunities for income stabilization through diversification. With respect to transitory income, Ra, vary from 0.000006 to 0.000361 and the absolute coefficient of risk aversion in our sample were 0.00005. The estimated Ra values vary considerably from farm to farm. The results showed that the estimated Ra for the subsample existing of 'non-wealthy' farmers was 0.00010. The subsample with farmers in the 'wealthy' group had an

Deciding for Others Reduces Loss Aversion

DEFF Research Database (Denmark)

Andersson, Ola; Holm, Håkan J.; Tyran, Jean-Robert Karl

2016-01-01

We study risk taking on behalf of others, both when choices involve losses and when they do not. A large-scale incentivized experiment with subjects randomly drawn from the Danish population is conducted. We find that deciding for others reduces loss aversion. When choosing between risky prospects...... when losses loom. This finding is consistent with an interpretation of loss aversion as a bias in decision making driven by emotions and that these emotions are reduced when making decisions for others....... for which losses are ruled out by design, subjects make the same choices for themselves as for others. In contrast, when losses are possible, we find that the two types of choices differ. In particular, we find that subjects who make choices for themselves take less risk than those who decide for others...

Gender Differences in Risk Aversion Among Chinese University Students.

Science.gov (United States)

Lam, Desmond

2015-12-01

This paper examines gender differences in risk aversion among Chinese university students. Chinese females are proposed to be more risk averse and require a higher risk premium when faced with a gamble option in the gain-domain frame as compared to Chinese males. Two groups of 100 participants each (male = 100 and female = 100 in total) were recruited to fill up questionnaires that included items relating to objective probability lotteries. Within each group, it was found that Chinese males and females did not differ in their risk aversion. However, results show that Chinese males tend to react more readily to rising risk premium by taking up options with higher expected values when compared to Chinese females. Current findings will have useful implications to marketers (particularly, promoters of gambling products) and problem gambling counselors.

Amygdala signals subjective appetitiveness and aversiveness of mixed gambles

DEFF Research Database (Denmark)

Gelskov, Sofie V.; Henningsson, Susanne; Madsen, Kristoffer Hougaard

2015-01-01

People are more sensitive to losses than to equivalent gains when making financial decisions. We used functional magnetic resonance imaging (fMRI) to illuminate how the amygdala contributes to loss aversion. The blood oxygen level dependent (BOLD) response of the amygdala was mapped while healthy...... individuals were responding to 50/50 gambles with varying potential gain and loss amounts. Overall, subjects demanded twice as high potential gain as loss to accept a gamble. The individual level of loss aversion was expressed by the decision boundary, i.e., the gain-loss ratio at which subjects accepted...... and rejected gambles with equal probability. Amygdala activity increased the more the gain-loss ratio deviated from the individual decision boundary showing that the amygdala codes action value. This response pattern was more strongly expressed in loss aversive individuals, linking amygdala activity...

The importance of risk-aversion as a measurable psychological parameter governing risk-taking behaviour

International Nuclear Information System (INIS)

Thomas, P J

2013-01-01

A utility function with risk-aversion as its sole parameter is developed and used to examine the well-known psychological phenomenon, whereby risk averse people adopt behavioural strategies that are extreme and apparently highly risky. The pioneering work of the psychologist, John W. Atkinson, is revisited, and utility theory is used to extend his mathematical model. His explanation of the psychology involved is improved by regarding risk-aversion not as a discrete variable with three possible states: risk averse, risk neutral and risk confident, but as continuous and covering a large range. A probability distribution is derived, the m otivational density , to describe the process of selecting tasks of different degrees of difficulty. An assessment is then made of practicable methods for measuring risk-aversion

The importance of risk-aversion as a measurable psychological parameter governing risk-taking behaviour

Science.gov (United States)

Thomas, P. J.

2013-09-01

A utility function with risk-aversion as its sole parameter is developed and used to examine the well-known psychological phenomenon, whereby risk averse people adopt behavioural strategies that are extreme and apparently highly risky. The pioneering work of the psychologist, John W. Atkinson, is revisited, and utility theory is used to extend his mathematical model. His explanation of the psychology involved is improved by regarding risk-aversion not as a discrete variable with three possible states: risk averse, risk neutral and risk confident, but as continuous and covering a large range. A probability distribution is derived, the "motivational density", to describe the process of selecting tasks of different degrees of difficulty. An assessment is then made of practicable methods for measuring risk-aversion.

Appetitive but Not Aversive Olfactory Conditioning Modifies Antennal Movements in Honeybees

Science.gov (United States)

Cholé, Hanna; Junca, Pierre; Sandoz, Jean-Christophe

2015-01-01

In honeybees, two olfactory conditioning protocols allow the study of appetitive and aversive Pavlovian associations. Appetitive conditioning of the proboscis extension response (PER) involves associating an odor, the conditioned stimulus (CS) with a sucrose solution, the unconditioned stimulus (US). Conversely, aversive conditioning of the sting…

Choice by value encoding and value construction : processes of loss aversion

NARCIS (Netherlands)

Willemsen, M.C.; Boeckenholt, U.; Johnson, E.J.

2011-01-01

Loss aversion and reference dependence are 2 keystones of behavioral theories of choice, but little is known about their underlying cognitive processes. We suggest an additional account for loss aversion that supplements the current account of the value encoding of attributes as gains or losses

Conditioned taste aversion, drugs of abuse and palatability.

Science.gov (United States)

Lin, Jian-You; Arthurs, Joe; Reilly, Steve

2014-09-01

We consider conditioned taste aversion to involve a learned reduction in the palatability of a taste (and hence in amount consumed) based on the association that develops when a taste experience is followed by gastrointestinal malaise. The present article evaluates the well-established finding that drugs of abuse, at doses that are otherwise considered rewarding and self-administered, cause intake suppression. Our recent work using lick pattern analysis shows that drugs of abuse also cause a palatability downshift and, therefore, support conditioned taste aversion learning. Copyright © 2014 Elsevier Ltd. All rights reserved.

The neural basis of loss aversion in decision-making under risk.

Science.gov (United States)

Tom, Sabrina M; Fox, Craig R; Trepel, Christopher; Poldrack, Russell A

2007-01-26

People typically exhibit greater sensitivity to losses than to equivalent gains when making decisions. We investigated neural correlates of loss aversion while individuals decided whether to accept or reject gambles that offered a 50/50 chance of gaining or losing money. A broad set of areas (including midbrain dopaminergic regions and their targets) showed increasing activity as potential gains increased. Potential losses were represented by decreasing activity in several of these same gain-sensitive areas. Finally, individual differences in behavioral loss aversion were predicted by a measure of neural loss aversion in several regions, including the ventral striatum and prefrontal cortex.

Are ambiguity aversion and ambiguity intolerance identical? A neuroeconomics investigation.

Science.gov (United States)

Tanaka, Yusuke; Fujino, Junya; Ideno, Takashi; Okubo, Shigetaka; Takemura, Kazuhisa; Miyata, Jun; Kawada, Ryosaku; Fujimoto, Shinsuke; Kubota, Manabu; Sasamoto, Akihiko; Hirose, Kimito; Takeuchi, Hideaki; Fukuyama, Hidenao; Murai, Toshiya; Takahashi, Hidehiko

2014-01-01

In recent years, there has been growing interest in understanding a person's reaction to ambiguous situations, and two similar constructs related to ambiguity, "ambiguity aversion" and "ambiguity intolerance," are defined in different disciplines. In the field of economic decision-making research, "ambiguity aversion" represents a preference for known risks relative to unknown risks. On the other hand, in clinical psychology, "ambiguity intolerance" describes the tendency to perceive ambiguous situations as undesirable. However, it remains unclear whether these two notions derived from different disciplines are identical or not. To clarify this issue, we combined an economic task, psychological questionnaires, and voxel-based morphometry (VBM) of structural brain magnetic resonance imaging (MRI) in a sample of healthy volunteers. The individual ambiguity aversion tendency parameter, as measured by our economic task, was negatively correlated with agreeableness scores on the self-reported version of the Revised NEO Personality Inventory. However, it was not correlated with scores of discomfort with ambiguity, one of the subscales of the Need for Closure Scale. Furthermore, the ambiguity aversion tendency parameter was negatively correlated with gray matter (GM) volume of areas in the lateral prefrontal cortex and parietal cortex, whereas ambiguity intolerance was not correlated with GM volume in any region. Our results suggest that ambiguity aversion, described in decision theory, may not necessarily be identical to ambiguity intolerance, referred to in clinical psychology. Cautious applications of decision theory to clinical neuropsychiatry are recommended.

Managing Risk Aversion for Low-Carbon Supply Chains with Emission Abatement Outsourcing

Science.gov (United States)

Wang, Qinpeng; He, Longfei

2018-01-01

Reducing carbon emissions, including emission abatement outsourcing at the supply-chain level, is becoming a significant but challenging problem in practice. Confronting this challenge, we therefore break down the practice to focus on a low-carbon supply chain consisting of one supplier, one manufacturer and one third-party emission-reducing contractor. The contractor offers a carbon reduction service to the manufacturer. In view of the increasing proportion of Greenhouse Gases (GHG) emissions and absence of carbon reduction policies in developing countries, we adopt the prospect of consumers’ low-carbon preferences to capture the demand sensitivity on carbon emission. By exploiting the Mean-Variance (MV) model, we develop a supply chain game model considering risk aversion. Comparing the supply chain performances of the cases under risk neutrality and risk aversion, we investigate the impact of the risk aversion of the supplier and the manufacturer on the low-carbon supply chain performances, respectively. We show that the risk aversion of chain members will not influence the relationship underlain by the profit-sharing contract between the manufacturer and contractor, whereas they may extend the supplier’s concerning range. Although the manufacturer’s risk aversion has a positive impact on the wholesale price, interestingly, the supplier’s impact on the wholesale price is negative. Furthermore, we propose a contract to coordinate the risk-averse low-carbon supply chain by tuning the aversion levels of the supplier and the manufacturer, respectively. Through numerical study, we draw on managerial insights for industrial practitioners to adopt a low carbon strategy potentially by managing the risk attitudes along the supply chain channel. PMID:29466281

Managing Risk Aversion for Low-Carbon Supply Chains with Emission Abatement Outsourcing

Directory of Open Access Journals (Sweden)

Qinpeng Wang

2018-02-01

Full Text Available Reducing carbon emissions, including emission abatement outsourcing at the supply-chain level, is becoming a significant but challenging problem in practice. Confronting this challenge, we therefore break down the practice to focus on a low-carbon supply chain consisting of one supplier, one manufacturer and one third-party emission-reducing contractor. The contractor offers a carbon reduction service to the manufacturer. In view of the increasing proportion of Greenhouse Gases (GHG emissions and absence of carbon reduction policies in developing countries, we adopt the prospect of consumers’ low-carbon preferences to capture the demand sensitivity on carbon emission. By exploiting the Mean-Variance (MV model, we develop a supply chain game model considering risk aversion. Comparing the supply chain performances of the cases under risk neutrality and risk aversion, we investigate the impact of the risk aversion of the supplier and the manufacturer on the low-carbon supply chain performances, respectively. We show that the risk aversion of chain members will not influence the relationship underlain by the profit-sharing contract between the manufacturer and contractor, whereas they may extend the supplier’s concerning range. Although the manufacturer’s risk aversion has a positive impact on the wholesale price, interestingly, the supplier’s impact on the wholesale price is negative. Furthermore, we propose a contract to coordinate the risk-averse low-carbon supply chain by tuning the aversion levels of the supplier and the manufacturer, respectively. Through numerical study, we draw on managerial insights for industrial practitioners to adopt a low carbon strategy potentially by managing the risk attitudes along the supply chain channel.

A pilot study of loss aversion for drug and non-drug commodities in cocaine users.

Science.gov (United States)

Strickland, Justin C; Beckmann, Joshua S; Rush, Craig R; Stoops, William W

2017-11-01

Numerous studies in behavioral economics have demonstrated that individuals are more sensitive to the prospect of a loss than a gain (i.e., loss aversion). Although loss aversion has been well described in "healthy" populations, little research exists in individuals with substance use disorders. This gap is notable considering the prominent role that choice and decision-making play in drug use. The purpose of this pilot study was to evaluate loss aversion in active cocaine users. Current cocaine users (N=38; 42% female) participated in this within-subjects laboratory pilot study. Subjects completed a battery of tasks designed to assess loss aversion for drug and non-drug commodities under varying risk conditions. Standardized loss aversion coefficients (λ) were compared to theoretically and empirically relevant normative values (i.e., λ=2). Compared to normative loss aversion coefficient values, a precise and consistent decrease in loss aversion was observed in cocaine users (sample λ≈1). These values were observed across drug and non-drug commodities as well as under certain and risky conditions. These data represent the first systematic study of loss aversion in cocaine-using populations and provide evidence for equal sensitivity to losses and gains or loss equivalence. Futures studies should evaluate the specificity of these effects to a history of cocaine use as well as the impact of manipulations of loss aversion on drug use to determine how this phenomenon may contribute to intervention development efforts. Copyright © 2017 Elsevier B.V. All rights reserved.

Taste aversion learning produced by combined treatment with subthreshold radiation and lithium chloride

International Nuclear Information System (INIS)

Rabin, B.M.; Hunt, W.A.; Lee, J.

1987-01-01

These experiments were designed to determine whether treatment with two subthreshold doses of radiation or lithium chloride, either alone or in combination, could lead to taste aversion learning. The first experiment determined the thresholds for a radiation-induced taste aversion at 15-20 rad and for lithium chloride at 0.30-0.45 mEq/kg. In the second experiment it was shown that exposing rats to two doses of 15 rad separated by up to 3 hr produced a taste aversion. Treatment with two injections of lithium chloride (0.30 mEq/kg) did not produce a significant reduction in preference. Combined treatment with radiation and lithium chloride did produce a taste aversion when the two treatments were administered within 1 hr of each other. The results are discussed in terms of the implications of these findings for understanding the nature of the unconditioned stimuli leading to the acquisition of a conditioned taste aversion

Uncertainty, loss aversion, and markets for energy efficiency

International Nuclear Information System (INIS)

Greene, David L.

2011-01-01

Increasing energy efficiency is critical to mitigating greenhouse gas emissions from fossil-fuel combustion, reducing oil dependence, and achieving a sustainable global energy system. The tendency of markets to neglect apparently cost-effective energy efficiency options has been called the 'efficiency gap' or 'energy paradox.' The market for energy efficiency in new, energy-using durable goods, however, appears to have a bias that leads to undervaluation of future energy savings relative to their expected value. This paper argues that the bias is chiefly produced by the combination of substantial uncertainty about the net value of future fuel savings and the loss aversion of typical consumers. This framework relies on the theory of context-dependent preferences. The uncertainty-loss aversion bias against energy efficiency is quantifiable, making it potentially correctible by policy measures. The welfare economics of such policies remains unresolved. Data on the costs of increased fuel economy of new passenger cars, taken from a National Research Council study, illustrate how an apparently cost-effective increase in energy efficiency would be uninteresting to loss-averse consumers.

Onset and Offset of Aversive Events Establish Distinct Memories Requiring Fear and Reward Networks

Science.gov (United States)

Andreatta, Marta; Fendt, Markus; Muhlberger, Andreas; Wieser, Matthias J.; Imobersteg, Stefan; Yarali, Ayse; Gerber, Bertram; Pauli, Paul

2012-01-01

Two things are worth remembering about an aversive event: What made it happen? What made it cease? If a stimulus precedes an aversive event, it becomes a signal for threat and will later elicit behavior indicating conditioned fear. However, if the stimulus is presented upon cessation of the aversive event, it elicits behavior indicating…

Experimental evidence against the paradigm of mortality risk aversion.

Science.gov (United States)

Rheinberger, Christoph M

2010-04-01

This article deals with the question of how societal impacts of fatal accidents can be integrated into the management of natural or man-made hazards. Today, many governmental agencies give additional weight to the number of potential fatalities in their risk assessments to reflect society's aversion to large accidents. Although mortality risk aversion has been proposed in numerous risk management guidelines, there has been no evidence that lay people want public decisionmakers to overweight infrequent accidents of large societal consequences against more frequent ones of smaller societal consequences. Furthermore, it is not known whether public decisionmakers actually do such overweighting when they decide upon the mitigation of natural or technical hazards. In this article, we report on two experimental tasks that required participants to evaluate negative prospects involving 1-100 potential fatalities. Our results show that neither lay people nor hazard experts exhibit risk-averse behavior in decisions on mortality risks.

Taste aversion memory reconsolidation is independent of its retrieval.

Science.gov (United States)

Rodriguez-Ortiz, Carlos J; Balderas, Israela; Garcia-DeLaTorre, Paola; Bermudez-Rattoni, Federico

2012-10-01

Reconsolidation refers to the destabilization/re-stabilization memory process upon its activation. However, the conditions needed to undergo reconsolidation, as well as its functional significance is quite unclear and a matter of intense investigation. Even so, memory retrieval is held as requisite to initiate reconsolidation. Therefore, in the present work we examined whether transient pharmacological disruption of memory retrieval impedes reconsolidation of stored memory in the widely used associative conditioning task, taste aversion. We found that AMPA receptors inhibition in the amygdala impaired retrieval of taste aversion memory. Furthermore, AMPA receptors blockade impeded retrieval regardless of memory strength. However, inhibition of retrieval did not affect anisomycin-mediated disruption of reconsolidation. These results indicate that retrieval is a dispensable condition to undergo reconsolidation and provide evidence of molecular dissociation between retrieval and activation of memory in the non-declarative memory model taste aversion. Copyright © 2012 Elsevier Inc. All rights reserved.

Neural systems underlying aversive conditioning in humans with primary and secondary reinforcers

Directory of Open Access Journals (Sweden)

Mauricio R Delgado

2011-05-01

Full Text Available Money is a secondary reinforcer commonly used across a range of disciplines in experimental paradigms investigating reward learning and decision-making. The effectiveness of monetary reinforcers during aversive learning and its neural basis, however, remains a topic of debate. Specifically, it is unclear if the initial acquisition of aversive representations of monetary losses depends on similar neural systems as more traditional aversive conditioning that involves primary reinforcers. This study contrasts the efficacy of a biologically defined primary reinforcer (shock and a socially defined secondary reinforcer (money during aversive learning and its associated neural circuitry. During a two-part experiment, participants first played a gambling game where wins and losses were based on performance to gain an experimental bank. Participants were then exposed to two separate aversive conditioning sessions. In one session, a primary reinforcer (mild shock served as an unconditioned stimulus (US and was paired with one of two colored squares, the conditioned stimuli (CS+ and CS-, respectively. In another session, a secondary reinforcer (loss of money served as the US and was paired with one of two different CS. Skin conductance responses were greater for CS+ compared to CS- trials irrespective of type of reinforcer. Neuroimaging results revealed that the striatum, a region typically linked with reward-related processing, was found to be involved in the acquisition of aversive conditioned response irrespective of reinforcer type. In contrast, the amygdala was involved during aversive conditioning with primary reinforcers, as suggested by both an exploratory fMRI analysis and a follow-up case study with a patient with bilateral amygdala damage. Taken together, these results suggest that learning about potential monetary losses may depend on reinforcement learning related systems, rather than on typical structures involved in more biologically based

The Effect of Wealth Shocks on Loss Aversion: Behavior and Neural Correlates

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V. S. Chandrasekhar Pammi

2017-04-01

Full Text Available Kahneman and Tversky (1979 first demonstrated that when individuals decide whether or not to accept a gamble, potential losses receive more weight than possible gains in the decision. This phenomenon is referred to as loss aversion. We investigated how loss aversion in risky financial decisions is influenced by sudden changes to wealth, employing both behavioral and neurobiological measures. We implemented an fMRI experimental paradigm, based on that employed by Tom et al. (2007. There are two treatments, called RANDOM and CONTINGENT. In RANDOM, the baseline setting, the changes to wealth, referred to as wealth shocks in economics, are independent of the actual choices participants make. Under CONTINGENT, we induce the belief that the changes in income are a consequence of subjects' own decisions. The magnitudes and sequence of the shocks to wealth are identical between the CONTINGENT and RANDOM treatments. We investigated whether more loss aversion existed in one treatment than another. The behavioral results showed significantly greater loss aversion in CONTINGENT compared to RANDOM after a negative wealth shock. No differences were observed in the response to positive shocks. The fMRI results revealed a neural loss aversion network, comprising the bilateral striatum, amygdala and dorsal anterior cingulate cortex that was common to the CONTINGENT and RANDOM tasks. However, the ventral prefrontal cortex, primary somatosensory cortex and superior occipital cortex, showed greater activation in response to a negative change in wealth due to individual's own decisions than when the change was exogenous. These results indicate that striatum activation correlates with loss aversion independently of the source of the shock, and that the ventral prefrontal cortex (vPFC codes the experimental manipulation of agency in one's actions influencing loss aversion.

The Effect of Wealth Shocks on Loss Aversion: Behavior and Neural Correlates.

Science.gov (United States)

Pammi, V S Chandrasekhar; Ruiz, Sergio; Lee, Sangkyun; Noussair, Charles N; Sitaram, Ranganatha

2017-01-01

Kahneman and Tversky (1979) first demonstrated that when individuals decide whether or not to accept a gamble, potential losses receive more weight than possible gains in the decision. This phenomenon is referred to as loss aversion. We investigated how loss aversion in risky financial decisions is influenced by sudden changes to wealth, employing both behavioral and neurobiological measures. We implemented an fMRI experimental paradigm, based on that employed by Tom et al. (2007). There are two treatments, called RANDOM and CONTINGENT. In RANDOM, the baseline setting, the changes to wealth, referred to as wealth shocks in economics, are independent of the actual choices participants make. Under CONTINGENT, we induce the belief that the changes in income are a consequence of subjects' own decisions. The magnitudes and sequence of the shocks to wealth are identical between the CONTINGENT and RANDOM treatments. We investigated whether more loss aversion existed in one treatment than another. The behavioral results showed significantly greater loss aversion in CONTINGENT compared to RANDOM after a negative wealth shock. No differences were observed in the response to positive shocks. The fMRI results revealed a neural loss aversion network, comprising the bilateral striatum, amygdala and dorsal anterior cingulate cortex that was common to the CONTINGENT and RANDOM tasks. However, the ventral prefrontal cortex, primary somatosensory cortex and superior occipital cortex, showed greater activation in response to a negative change in wealth due to individual's own decisions than when the change was exogenous. These results indicate that striatum activation correlates with loss aversion independently of the source of the shock, and that the ventral prefrontal cortex (vPFC) codes the experimental manipulation of agency in one's actions influencing loss aversion.

Amygdala activity related to enhanced memory for pleasant and aversive stimuli.

Science.gov (United States)

Hamann, S B; Ely, T D; Grafton, S T; Kilts, C D

1999-03-01

Pleasant or aversive events are better remembered than neutral events. Emotional enhancement of episodic memory has been linked to the amygdala in animal and neuropsychological studies. Using positron emission tomography, we show that bilateral amygdala activity during memory encoding is correlated with enhanced episodic recognition memory for both pleasant and aversive visual stimuli relative to neutral stimuli, and that this relationship is specific to emotional stimuli. Furthermore, data suggest that the amygdala enhances episodic memory in part through modulation of hippocampal activity. The human amygdala seems to modulate the strength of conscious memory for events according to emotional importance, regardless of whether the emotion is pleasant or aversive.

Rewarding and aversive effects of nicotine are segregated within the nucleus accumbens.

Science.gov (United States)

Sellings, Laurie H L; Baharnouri, Golriz; McQuade, Lindsey E; Clarke, Paul B S

2008-07-01

Forebrain dopamine plays a critical role in motivated behavior. According to the classic view, mesolimbic dopamine selectively guides behavior motivated by positive reinforcers. However, this has been challenged in favor of a wider role encompassing aversively motivated behavior. This controversy is particularly striking in the case of nicotine, with opposing claims that either the rewarding or the aversive effect of nicotine is critically dependent on mesolimbic dopamine transmission. In the present study, the effects of 6-hydroxydopamine lesions of nucleus accumbens core vs. medial shell on intravenous nicotine conditioned place preference and conditioned taste aversion were examined in male adult rats. Dopaminergic denervation in accumbens medial shell was associated with decreased nicotine conditioned place preference. Conversely, denervation in accumbens core was associated with an increase in conditioned place preference. In addition, dopaminergic denervation of accumbens core but not medial shell abolished conditioned taste aversion for nicotine. We conclude that nucleus accumbens core and medial shell dopaminergic innervation exert segregated effects on rewarding and aversive effects of nicotine. More generally, our findings indicate that dopaminergic transmission may mediate or enable opposing motivational processes within functionally distinct domains of the accumbens.

Overcoming Learning Aversion in Evaluating and Managing Uncertain Risks.

Science.gov (United States)

Cox, Louis Anthony Tony

2015-10-01

Decision biases can distort cost-benefit evaluations of uncertain risks, leading to risk management policy decisions with predictably high retrospective regret. We argue that well-documented decision biases encourage learning aversion, or predictably suboptimal learning and premature decision making in the face of high uncertainty about the costs, risks, and benefits of proposed changes. Biases such as narrow framing, overconfidence, confirmation bias, optimism bias, ambiguity aversion, and hyperbolic discounting of the immediate costs and delayed benefits of learning, contribute to deficient individual and group learning, avoidance of information seeking, underestimation of the value of further information, and hence needlessly inaccurate risk-cost-benefit estimates and suboptimal risk management decisions. In practice, such biases can create predictable regret in selection of potential risk-reducing regulations. Low-regret learning strategies based on computational reinforcement learning models can potentially overcome some of these suboptimal decision processes by replacing aversion to uncertain probabilities with actions calculated to balance exploration (deliberate experimentation and uncertainty reduction) and exploitation (taking actions to maximize the sum of expected immediate reward, expected discounted future reward, and value of information). We discuss the proposed framework for understanding and overcoming learning aversion and for implementing low-regret learning strategies using regulation of air pollutants with uncertain health effects as an example. © 2015 Society for Risk Analysis.

Anticipation of high arousal aversive and positive movie clips engages common and distinct neural substrates.

Science.gov (United States)

Greenberg, Tsafrir; Carlson, Joshua M; Rubin, Denis; Cha, Jiook; Mujica-Parodi, Lilianne

2015-04-01

The neural correlates of anxious anticipation have been primarily studied with aversive and neutral stimuli. In this study, we examined the effect of valence on anticipation by using high arousal aversive and positive stimuli and a condition of uncertainty (i.e. either positive or aversive). The task consisted of predetermined cues warning participants of upcoming aversive, positive, 'uncertain' (either aversive or positive) and neutral movie clips. Anticipation of all affective clips engaged common regions including the anterior insula, dorsal anterior cingulate cortex, thalamus, caudate, inferior parietal and prefrontal cortex that are associated with emotional experience, sustained attention and appraisal. In contrast, the nucleus accumbens and medial prefrontal cortex, regions implicated in reward processing, were selectively engaged during anticipation of positive clips (depicting sexually explicit content) and the mid-insula, which has been linked to processing aversive stimuli, was selectively engaged during anticipation of aversive clips (depicting graphic medical procedures); these three areas were also activated during anticipation of 'uncertain' clips reflecting a broad preparatory response for both aversive and positive stimuli. These results suggest that a common circuitry is recruited in anticipation of affective clips regardless of valence, with additional areas preferentially engaged depending on whether expected stimuli are negative or positive. © The Author (2014). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Contrasting role of octopamine in appetitive and aversive learning in the crab Chasmagnathus.

Directory of Open Access Journals (Sweden)

Laura Kaczer

Full Text Available BACKGROUND: Biogenic amines are implicated in reinforcing associative learning. Octopamine (OA is considered the invertebrate counterpart of noradrenaline and several studies in insects converge on the idea that OA mediates the reward in appetitive conditioning. However, it is possible to assume that OA could have a different role in an aversive conditioning. METHODOLOGY/PRINCIPAL FINDINGS: Here we pharmacologically studied the participation of OA in two learning processes in the crab Chasmagnathus granulatus, one appetitive and one aversive. It is shown that the aversive memory is impaired by an OA injection applied immediately or 30 minutes after the last training trial. By contrast, the appetitive memory is blocked by OA antagonists epinastine and mianserine, but enhanced by OA when injected together with the supply of a minimum amount of reinforcement. Finally, double-learning experiments in which crabs are given the aversive and the appetitive learning either successively or simultaneously allow us to study the interaction between both types of learning and analyze the presumed action of OA. We found that the appetitive training offered immediately, but not one hour, after an aversive training has an amnesic effect on the aversive memory, mimicking the effect and the kinetic of an OA injection. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that the role of OA is divergent in two memory processes of opposite signs: on the one hand it would mediate the reinforcement in appetitive learning, and on the other hand it has a deleterious effect over aversive memory consolidation.

Comparing uncertainty aversion towards different sources

NARCIS (Netherlands)

Baillon, Aurélien; Liu, Ning; van Dolder, Dennie

2017-01-01

We propose simple behavioral definitions of comparative uncertainty aversion for a single agent towards different sources of uncertainty. Our definitions allow for the comparison of utility curvature for different sources if the agent’s choices satisfy subjective expected utility towards each

The Role of Risk Aversion in Predicting Individual Behaviours

OpenAIRE

Guiso, Luigi; Paiella, Monica

2004-01-01

We use household survey data to construct a direct measure of absolute risk aversion based on the maximum price a consumer is willing to pay to buy a risky asset. We relate this measure to a set of consumers’ decisions that in theory should vary with attitude towards risk. We find that elicited risk aversion has considerable predictive power for a number of key household decisions such as choice of occupation, portfolio selection, moving decisions and exposure to chronic diseases in ways cons...

The Role of Risk Aversion in Predicting Individual Behaviour

OpenAIRE

Monica Paiella; Luigi Guiso

2004-01-01

We use household survey data to construct a direct measure of absolute risk aversion based on the maximum price a consumer is willing to pay to buy a risky asset. We relate this measure to a set of consumers' decisions that in theory should vary with attitude towards risk. We find that elicited risk aversion has considerable predictive power for a number of key household decisions such as choice of occupation, portfolio selection, moving decisions and exposure to chronic diseases in ways cons...

Choice by Value Encoding and Value Construction: Processes of Loss Aversion

Science.gov (United States)

Willemsen, Martijn C.; Bockenholt, Ulf; Johnson, Eric J.

2011-01-01

Loss aversion and reference dependence are 2 keystones of behavioral theories of choice, but little is known about their underlying cognitive processes. We suggest an additional account for loss aversion that supplements the current account of the value encoding of attributes as gains or losses relative to a reference point, introducing a value…

Risk-Averse Evolutionary Game Model of Aviation Joint Emergency Response

Directory of Open Access Journals (Sweden)

Wei Pan

2016-01-01

Full Text Available We study effects of risk-averse attitude of both participators in aviation joint emergency response on the coevolution of cooperation mechanisms and individual preferences between airport and nonprofit organization. First, based on the current aviation joint emergency mechanism in China, we put forward two mechanisms to select the joint nonprofit organization, including reputation cooperation and bidding competition. Meanwhile, we consider two preferences including altruism and selfishness. Then we build replicator dynamics equations using the theory of conditional value-at-risk (CVaR taking risk aversion attitude into account. Finally, we introduce the factor of government and give all participators some suggestions. We show that the risk-averse attitude of the other game participator affects the one participator’s decision and the effects subject to some parameters.

Determinants of propranolol’s selective effect on loss aversion

Science.gov (United States)

Sokol-Hessner, Peter; Lackovic, Sandra F.; Tobe, Russell H.; Camerer, Colin F.; Leventhal, Bennett L.; Phelps, Elizabeth A.

2015-01-01

Research on emotion and decision-making has suggested that arousal mediates risky decisions (e.g., Bechara et al., 1997), but several distinct and often confounded processes drive such choices. Here, we used econometric modeling to separate and quantify the unique contributions of loss aversion, risk sensitivity and choice consistency to risky decision-making. We administered the beta-blocker propranolol in a double-blind, placebo-controlled within-subjects study, targeting the neurohormonal basis of physiological arousal. Matching our intervention’s pharmacological specificity with a quantitative model delineating decision-making components allowed us to identify the causal relationships between arousal and decision-making that do and do not exist. Propranolol selectively reduced loss aversion in a baseline- and dose-dependent manner (i.e. as a function of initial loss aversion and body-mass index), and did not affect risk sensitivity or choice consistency. These findings provide evidence for a specific, modulatory, and causal relationship between precise components of both emotion and risky decision-making. PMID:26063441

On the descriptive value of loss aversion in decisions under risk: Six clarifications

OpenAIRE

Eyal Ert; Ido Erev

2013-01-01

Previous studies of loss aversion in decisions under risk have led to mixed results. Losses appear to loom larger than gains in some settings, but not in others. The current paper clarifies these results by highlighting six experimental manipulations that tend to increase the likelihood of the behavior predicted by loss aversion. These manipulations include: (1) framing of the safe alternative as the status quo; (2) ensuring that the choice pattern predicted by loss aversion maximizes the pro...

"Incidental fear cues increase monetary loss aversion": Correction to Schulreich, Gerhardt, and Heekeren (2016).

Science.gov (United States)

2016-12-01

Reports an error in "Incidental fear cues increase monetary loss aversion" by Stefan Schulreich, Holger Gerhardt and Hauke R. Heekeren ( Emotion , 2016[Apr], Vol 16[3], 402-412). In the current article, there was an error in the Study 2 portion of the article. The fourth paragraph of the Results section should read as follows: Performing the same analyses as in Study 1, we found an effect of incidental fear cues on decision behavior. Participants accepted fewer gambles in the fearful-face condition (32.77%) than in the neutral-face condition (33.96%), with Z = -2.187, p = .027, d = -0.998 in the Wilcoxon signed-ranks test and β = 0.012, SE = 0.0053, F(1, 21) = 4.434, p = .047, partial η² = .174 in the linear regression. This suggests increased risk aversion in the fearful-face condition. Concerning personality, however, there were no significant between-subjects effects or between-within interaction effects (all ps = .349). (The following abstract of the original article appeared in record 2015-52358-001.) In many everyday decisions, people exhibit loss aversion-a greater sensitivity to losses relative to gains of equal size. Loss aversion is thought to be (at least partly) mediated by emotional-in particular, fear-related-processes. Decision research has shown that even incidental emotions, which are unrelated to the decision at hand, can influence decision making. The effect of incidental fear on loss aversion, however, is thus far unclear. In two studies, we experimentally investigated how incidental fear cues, presented during (Study 1) or before (Study 2) choices to accept or reject mixed gambles over real monetary stakes, influence monetary loss aversion. We find that the presentation of fearful faces, relative to the presentation of neutral faces, increased risk aversion-an effect that could be attributed to increased loss aversion. The size of this effect was moderated by psychopathic personality: Fearless dominance, in particular its interpersonal facet

Neural loss aversion differences between depression patients and healthy individuals: A functional MRI investigation.

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Chandrasekhar Pammi, V S; Pillai Geethabhavan Rajesh, Purushothaman; Kesavadas, Chandrasekharan; Rappai Mary, Paramban; Seema, Satish; Radhakrishnan, Ashalatha; Sitaram, Ranganatha

2015-04-01

Neuroeconomics employs neuroscience techniques to explain decision-making behaviours. Prospect theory, a prominent model of decision-making, features a value function with parameters for risk and loss aversion. Recent work with normal participants identified activation related to loss aversion in brain regions including the amygdala, ventral striatum, and ventromedial prefrontal cortex. However, the brain network for loss aversion in pathologies such as depression has yet to be identified. The aim of the current study is to employ the value function from prospect theory to examine behavioural and neural manifestations of loss aversion in depressed and healthy individuals to identify the neurobiological markers of loss aversion in economic behaviour. We acquired behavioural data and fMRI scans while healthy controls and patients with depression performed an economic decision-making task. Behavioural loss aversion was higher in patients with depression than in healthy controls. fMRI results revealed that the two groups shared a brain network for value function including right ventral striatum, ventromedial prefrontal cortex, and right amygdala. However, the neural loss aversion results revealed greater activations in the right dorsal striatum and the right anterior insula for controls compared with patients with depression, and higher activations in the midbrain region ventral tegmental area for patients with depression compared with controls. These results suggest that while the brain network for loss aversion is shared between depressed and healthy individuals, some differences exist with respect to differential activation of additional areas. Our findings are relevant to identifying neurobiological markers for altered decision-making in the depressed. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Investigations on UCS-CS mediation in radiation-induced conditioned taste aversion

International Nuclear Information System (INIS)

Burns, T.C.

1974-01-01

Groups of 8 male Sprague-Dawley rats were used in an investigation of procaine and dimenhydrinate effects on radiation-induced taste aversion learning. Neither the local anesthetic procaine, administered intraperitoneally, nor the antinausea drug dimenhydrinate, administered intramuscularly, blocked acquisition of aversion to saccharin flavored water. Control animals confirmed that saccharin preferences appeared normally in non-irradiated animals, and that the drugs produced no aversion in the absence of radiation. Another investigation, using groups of 5 female Sprague-Dawley rats, showed a failure of dimenhydrinate in blocking the acquisition of a rotation-induced conditioned taste aversion. Two dose levels of the drug were used, 1 mg/kg and 2 mg/kg. At the dimenhydrinate dosage used in the study involving radiation (1.75 mg/kg) and at the higher dosage used in the study involving rotation, there appeared to be a potentiation of the effects of radiation and rotation, respectively. Results of these studies seem to favor a model for UCS-CS mediation as being diffuse and perhaps redundant. The possibility that nausea-producing stimuli may work synergistically was also discussed. (U.S.)

Risk Aversion: As Perceived by U.S. and Swedish Officers

Science.gov (United States)

2011-06-10

marginalized traditional morality . (Furedi 1997, 153f) The value of risk aversion means to not put people at risk and to regulate behavior. The main...difference compared to traditional morality lies in the individualistic orientation of risk aversion (Furedi 1997, 163) Ulrich Beck German Professor of...that distinguishes one group of people from another (Hofstede 2005, 3ff). Studying differences in culture demands a position of cultural relativism

The functional and structural neural basis of individual differences in loss aversion.

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Canessa, Nicola; Crespi, Chiara; Motterlini, Matteo; Baud-Bovy, Gabriel; Chierchia, Gabriele; Pantaleo, Giuseppe; Tettamanti, Marco; Cappa, Stefano F

2013-09-04

Decision making under risk entails the anticipation of prospective outcomes, typically leading to the greater sensitivity to losses than gains known as loss aversion. Previous studies on the neural bases of choice-outcome anticipation and loss aversion provided inconsistent results, showing either bidirectional mesolimbic responses of activation for gains and deactivation for losses, or a specific amygdala involvement in processing losses. Here we focused on loss aversion with the aim to address interindividual differences in the neural bases of choice-outcome anticipation. Fifty-six healthy human participants accepted or rejected 104 mixed gambles offering equal (50%) chances of gaining or losing different amounts of money while their brain activity was measured with functional magnetic resonance imaging (fMRI). We report both bidirectional and gain/loss-specific responses while evaluating risky gambles, with amygdala and posterior insula specifically tracking the magnitude of potential losses. At the individual level, loss aversion was reflected both in limbic fMRI responses and in gray matter volume in a structural amygdala-thalamus-striatum network, in which the volume of the "output" centromedial amygdala nuclei mediating avoidance behavior was negatively correlated with monetary performance. We conclude that outcome anticipation and ensuing loss aversion involve multiple neural systems, showing functional and structural individual variability directly related to the actual financial outcomes of choices. By supporting the simultaneous involvement of both appetitive and aversive processing in economic decision making, these results contribute to the interpretation of existing inconsistencies on the neural bases of anticipating choice outcomes.

Heterogenous Intertemporal Elasticity of Substitution and Relative Risk Aversion

DEFF Research Database (Denmark)

Khorunzhina, Natalia; Gayle, Wayne-Roy

This paper investigates the existence and degree of variation across house holds and over time in the intertemporal elasticity of substitution (IES) and the coefficient of relative risk aversion (RRA) that is generated by habit forming preferences. To do so, we develop a new nonlinear GMM estimator...... in food consumption. Using these estimates, we develop bounds for the expectation of the implied heterogenous intertemporal elasticity of substitution and relative risk aversion that account for measurement errors and compute asymptotically valid confidence intervals on these bounds. We find...

THE ROLE OF RISK AVERSION IN PREDICTING INDIVIDUAL BEHAVIOR

OpenAIRE

Luigi Guiso; Monica Paiella

2005-01-01

We use household survey data to construct a direct measure of absolute risk aversion based on the maximum price a consumer is willing to pay to buy a risky asset. We relate this measure to a set of consumers� decisions that in theory should vary with attitude towards risk. We find that elicited risk aversion has considerable predictive power for a number of key household decisions such as choice of occupation, portfolio selection, moving decisions and exposure to chronic diseases in ways co...

Oxytocin attenuates aversive response to nicotine and anxiety-like behavior in adolescent rats.

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Lee, Hyunchan; Jang, Minji; Noh, Jihyun

2017-02-01

Initial tobacco use is initiated with rewarding and aversive properties of nicotine and aversive response to nicotine plays a critical role in nicotine dependency. Decrease of nicotine aversion increases the nicotine use that causes behavioral and neuronal changes of animals. Oxytocin influences drug abuse and reciprocally affect vulnerability to drug use. To assess the effect of oxytocin on initial nicotine aversion and anxiety, we examined voluntary oral nicotine intake and anxiety-like behavior following oxytocin treatment in adolescent rats. Sprague-Dawley male rats (4 weeks old) were used. For oxytocin administration, rats were injected subcutaneously with saline or oxytocin (0.01, 0.1 and 1mg/kg) according to the assigned groups. Voluntary oral nicotine consumption test was performed by two bottle free-choice paradigm. To examine anxiety-like behavior in rats, we performed a light/dark box test. Oxytocin not only significantly increased the nicotine intake but also alleviated nicotine aversion after acclimation to nicotine solution in a concentration dependent manner. Meanwhile, oxytocin significantly reduced anxiety-like behavior. We suggest that oxytocin itself mitigates aversive response toward initial nicotine intake and anxiety-like behavior. These results widen the psychophysiological perspective on oxytocin for better understanding of nicotine addiction related behaviors influenced by diverse social factors. Copyright © 2016 Elsevier Ireland Ltd and Japan Neuroscience Society. All rights reserved.

Loss aversion is associated with bilateral insula volume. A voxel based morphometry study.

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Markett, S; Heeren, G; Montag, C; Weber, B; Reuter, M

2016-04-21

Loss aversion is a decision bias, reflecting a greater sensitivity to losses than to gains in a decision situation. Recent neuroscientific research has shown that mesocorticolimbic structures like ventromedial prefrontal cortex and the ventral striatum constitute a bidirectional neural system that processes gains and losses and exhibits a neural basis of loss aversion. On a functional and structural level, the amygdala and insula also seem to play an important role in the processing of loss averse behavior. By applying voxel-based morphometry to structural brain images in N=41 healthy participants, the current study provides further evidence for the relationship of brain structure and loss aversion. The results show a negative correlation of gray matter volume in bilateral posterior insula as well as left medial frontal gyrus with individual loss aversion. Hence, higher loss aversion is associated with lower gray matter volume in these brain areas. Both structures have been discussed to play important roles in the brain's salience network, where the posterior insula is involved in interoception and the detection of salience. The medial frontal gyrus might impact decision making through its dense connections with the anterior cingulate cortex. A possible explanation for the present finding is that structural differences in these regions alter the processing of losses and salience, possibly biasing decision making towards avoidance of negative outcomes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Hiring a Gay Man, Taking a Risk?: A Lab Experiment on Employment Discrimination and Risk Aversion.

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Baert, Stijn

2018-01-01

We investigate risk aversion as a driver of labor market discrimination against homosexual men. We show that more hiring discrimination by more risk-averse employers is consistent with taste-based and statistical discrimination. To test this hypothesis we conduct a scenario experiment in which experimental employers take a fictitious hiring decision concerning a heterosexual or homosexual male job candidate. In addition, participants are surveyed on their risk aversion and other characteristics that might correlate with this risk aversion. Analysis of the (post-)experimental data confirms our hypothesis. The likelihood of a beneficial hiring decision for homosexual male candidates decreases by 31.7% when employers are a standard deviation more risk-averse.

Loss Aversion in the Classroom: A Nudge towards a Better Grade?

Science.gov (United States)

Grijalva, Therese; Koford, Brandon C.; Parkhurst, Gregory

2018-01-01

Using data from 499 students over 12 sections, 2 courses, and 3 instructors, we estimate the effect of loss aversion on the probability of turning in extra credit assignments and the effect on the overall grade. Regression results indicate no effect of loss aversion on the probability of turning in extra credit assignments and no effect on a…

Emotion-induced loss aversion and striatal-amygdala coupling in low-anxious individuals.

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Charpentier, Caroline J; De Martino, Benedetto; Sim, Alena L; Sharot, Tali; Roiser, Jonathan P

2016-04-01

Adapting behavior to changes in the environment is a crucial ability for survival but such adaptation varies widely across individuals. Here, we asked how humans alter their economic decision-making in response to emotional cues, and whether this is related to trait anxiety. Developing an emotional decision-making task for functional magnetic resonance imaging, in which gambling decisions were preceded by emotional and non-emotional primes, we assessed emotional influences on loss aversion, the tendency to overweigh potential monetary losses relative to gains. Our behavioral results revealed that only low-anxious individuals exhibited increased loss aversion under emotional conditions. This emotional modulation of decision-making was accompanied by a corresponding emotion-elicited increase in amygdala-striatal functional connectivity, which correlated with the behavioral effect across participants. Consistent with prior reports of 'neural loss aversion', both amygdala and ventral striatum tracked losses more strongly than gains, and amygdala loss aversion signals were exaggerated by emotion, suggesting a potential role for this structure in integrating value and emotion cues. Increased loss aversion and striatal-amygdala coupling induced by emotional cues may reflect the engagement of adaptive harm-avoidance mechanisms in low-anxious individuals, possibly promoting resilience to psychopathology. © The Author (2015). Published by Oxford University Press.

Increased dopaminergic signaling impairs aversive olfactory memory retention in Drosophila.

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Zhang, Shixing; Yin, Yan; Lu, Huimin; Guo, Aike

2008-05-23

Dopamine is necessary for the aversive olfactory associative memory formation in Drosophila, but its effect on other stages of memory is not known. Herein, we studied the effect of enhanced dopaminergic signaling on aversive olfactory memory retention in flies. We used l-3,4-dihydroxyphenylalanine (l-DOPA) to elevate dopamine levels: l-DOPA-treated flies exhibited a normal learning performance, but a decrease in 1-h memory. Dopamine transporter (DAT) mutant flies or flies treated with the DAT inhibitor desipramine exhibited poor memory retention. Flies subjected to heat stress after training exhibited a decrease in memory. Memory was restored by blocking dopaminergic neuronal output during heat stress, suggesting that dopamine is involved in heat stress-induced memory impairment in flies. Taken together, our findings suggest that increased dopaminergic signaling impairs aversive olfactory memory retention in flies.

Household portfolios and implicit risk aversion

NARCIS (Netherlands)

Bucciol, A.; Miniaci, R.

2008-01-01

We derive from a sample of US households the distribution of the risk aversion implicit in their portfolio choice. Our estimate minimizes the distance between the certainty equivalent return generated with observed portfolios and portfolios that are optimal in a mean-variance framework. Taking into

Effects of subdiaphragmatic vagotomy on the acquisition of a radiation-induced conditioned taste aversion

International Nuclear Information System (INIS)

Hunt, W.A.; Rabin, B.M.; Lee, J.

1987-01-01

The effect of subdiaphragmatic vagotomy on the acquisition of a radiation-induced taste aversion was examined to assess the importance of the vagus nerve in transmitting information on the peripheral toxicity of radiation to the brain. Vagotomy had no effect on taste aversion learning, consistent with reports using other toxins. The data support the involvement of a blood-borne factor in the acquisition of taste aversion induced by ionizing radiation

Modulation of the conflict monitoring intensity: the role of aversive reinforcement, cognitive demand, and trait-BIS.

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Leue, Anja; Lange, Sebastian; Beauducel, André

2012-06-01

According to Botvinick's (2007) integrative account, conflict monitoring is aversive because individuals anticipate cognitive demand, whereas the revised reinforcement sensitivity theory (rRST) predicts that conflict processing is aversive because individuals anticipate aversive reinforcement of erroneous responses. Because these accounts give different reasons for the aversive aspects of conflict, we manipulated cognitive demand and the aversive reinforcement as a consequence of wrong choices in a go/no-go task. Thereby, we also aimed to investigate whether individual differences in conflict sensitivity (i.e., in trait anxiety, linked to high sensitivity of the behavioral inhibition system [trait-BIS]) represent the effects of aversive reinforcement and cognitive demand in conflict tasks. We expected that these manipulations would have effects on the frontal N2 component representing activity of the anterior cingulate cortex. Moreover, higher-trait-BIS individuals should be more sensitive than lower-trait-BIS individuals to aversive effects in conflict situations, resulting in a more negative frontal N2 for higher-trait-BIS individuals. In Study 1, with N = 104 students, and Study 2, with N = 47 students, aversive reinforcement was manipulated in three levels (within-subjects factor) and cognitive demand in two levels (between-subjects factor). The behavioral findings from the go/no-go task with noncounterbalanced reinforcement levels (Study 1) could be widely replicated in a task with counterbalanced reinforcement levels (Study 2). The frontal mean no-go N2 amplitude and the frontal no-go N2 dipole captured predicted reinforcement-related variations of conflict monitoring, indicating that the anticipation of aversive reinforcement induces variations in conflict monitoring intensity in frontal brain areas. The aversive nature of conflict was underlined by the more pronounced conflict monitoring in higher- than in lower-trait-BIS individuals.

Mothers' depressive symptoms predict both increased and reduced negative reactivity: aversion sensitivity and the regulation of emotion.

Science.gov (United States)

Dix, Theodore; Moed, Anat; Anderson, Edward R

2014-07-01

This study examined whether, as mothers' depressive symptoms increase, their expressions of negative emotion to children increasingly reflect aversion sensitivity and motivation to minimize ongoing stress or discomfort. In multiple interactions over 2 years, negative affect expressed by 319 mothers and their children was observed across variations in mothers' depressive symptoms, the aversiveness of children's immediate behavior, and observed differences in children's general negative reactivity. As expected, depressive symptoms predicted reduced maternal negative reactivity when child behavior was low in aversiveness, particularly with children who were high in negative reactivity. Depressive symptoms predicted high negative reactivity and steep increases in negative reactivity as the aversiveness of child behavior increased, particularly when high and continued aversiveness from the child was expected (i.e., children were high in negative reactivity). The findings are consistent with the proposal that deficits in parenting competence as depressive symptoms increase reflect aversion sensitivity and motivation to avoid conflict and suppress children's aversive behavior. © The Author(s) 2014.

Contrasting Effects of Histone Deacetylase Inhibitors on Reward and Aversive Olfactory Memories in the Honey Bee

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Gabrielle A Lockett

2014-06-01

Full Text Available Much of what we have learnt from rodent models about the essential role of epigenetic processes in brain plasticity has made use of aversive learning, yet the role of histone acetylation in aversive memory in the honey bee, a popular invertebrate model for both memory and epigenetics, was previously unknown. We examined the effects of histone deacetylase (HDAC inhibition on both aversive and reward olfactory associative learning in a discrimination proboscis extension reflex (PER assay. We report that treatment with the HDAC inhibitors APHA compound 8 (C8, phenylbutyrate (PB or sodium butyrate (NaB impaired discrimination memory due to impairment of aversive memory in a dose-dependent manner, while simultaneously having no effect on reward memory. Treatment with C8 1 h before training, 1 h after training or 1 h before testing, impaired aversive but not reward memory at test. C8 treatment 1 h before training also improved aversive but not reward learning during training. PB treatment only impaired aversive memory at test when administered 1 h after training, suggesting an effect on memory consolidation specifically. Specific impairment of aversive memory (but not reward memory by HDAC inhibiting compounds was robust, reproducible, occurred following treatment with three drugs targeting the same mechanism, and is likely to be genuinely due to alterations to memory as sucrose sensitivity and locomotion were unaffected by HDAC inhibitor treatment. This pharmacological dissection of memory highlights the involvement of histone acetylation in aversive memory in the honey bee, and expands our knowledge of epigenetic control of neural plasticity in invertebrates.

Analysis of Behavioral Economics in Crowdsensing: A Loss Aversion Cooperation Model

Directory of Open Access Journals (Sweden)

Deng Li

2018-01-01

Full Text Available The existing incentive mechanisms of crowdsourcing construct the expected utility function based on the assumption of rational people in traditional economics. A large number of studies in behavioral economics have demonstrated the defects of the traditional utility function and introduced a new parameter called loss aversion coefficient to calculate individual utility when it suffers a loss. In this paper, combination of behavioral economics and a payment algorithm based on the loss aversion is proposed. Compared with usual incentive mechanisms, the node utility function is redefined by the loss aversion characteristic of the node. Experimental results show that the proposed algorithm can get a higher rate of cooperation with a lower payment price and has good scalability compared with the traditional incentive mechanism.

Lateral, Not Medial, Prefrontal Cortex Contributes to Punishment and Aversive Instrumental Learning

Science.gov (United States)

Jean-Richard-dit-Bressel , Philip; McNally, Gavan P.

2016-01-01

Aversive outcomes punish behaviors that cause their occurrence. The prefrontal cortex (PFC) has been implicated in punishment learning and behavior, although the exact roles for different PFC regions in instrumental aversive learning and decision-making remain poorly understood. Here, we assessed the role of the orbitofrontal (OFC), rostral…

Differences between appetitive and aversive reinforcement on reorientation in a spatial working memory task.

Science.gov (United States)

Golob, Edward J; Taube, Jeffrey S

2002-10-17

Tasks using appetitive reinforcers show that following disorientation rats use the shape of an arena to reorient, and cannot distinguish two geometrically similar corners to obtain a reward, despite the presence of a prominent visual cue that provides information to differentiate the two corners. Other studies show that disorientation impairs performance on certain appetitive, but not aversive, tasks. This study evaluated whether rats would make similar geometric errors in a working memory task that used aversive reinforcement. We hypothesized that in a task that used aversive reinforcement rats that were initially disoriented would not reorient by arena shape and thus make similar geometric errors. Tests were performed in a rectangular arena having one polarizing cue. In the appetitive condition water consumption was the reward. The aversive condition was a water maze task with reinforcement provided by escape to a hidden platform. In the aversive condition rats returned to the reinforced corner significantly more often than in the dry condition, and did not favor the diagonally opposite corner. Results show that rats can use cues besides arena shape to reorient in an aversive reinforcement condition. These findings may also reflect different strategies, with an escape/homing strategy in the wet condition and a foraging strategy in the dry condition.

Model dependencies of risk aversion and working interest estimates

International Nuclear Information System (INIS)

Lerche, I.

1996-01-01

Working interest, W, and risk adjusted value, RAV, are evaluated using both Cozzolino's formula for exponential dependence of risk aversion and also for a hyperbolic tangent dependence. In addition, the general method is given of constructing an RAV formula for any functional choice of risk aversion dependence. Two examples are given to illustrate how the model dependencies influence choices of working interest and risk adjusted value depending on whether the expected value of the project is positive or negative. In general the Cozzolino formula provides a more conservative position for risk than does the hyperbolic tangent formula, reflecting the difference in corporate attitudes to risk aversion. The commonly used Cozzolino formula is shown to have simple exact arithmetic expressions for maximum working interest and maximum RAV; the hyperbolic tangent formula has approximate analytic expressions. Both formulae also yield approximate analytical expressions for the working interest yielding a risk neutral RAV of zero. These arithmetic results are useful for making quick estimates of working interest ranges and risk adjusted values. (Author)

Random queues and risk averse users

DEFF Research Database (Denmark)

de Palma, André; Fosgerau, Mogens

2013-01-01

We analyze Nash equilibrium in time of use of a congested facility. Users are risk averse with general concave utility. Queues are subject to varying degrees of random sorting, ranging from strict queue priority to a completely random queue. We define the key “no residual queue” property, which...

Twins less frequent than expected among male births in risk averse populations.

Science.gov (United States)

Karasek, Deborah; Goodman, Julia; Gemmill, Alison; Falconi, April; Hartig, Terry; Magganas, Aristotle; Catalano, Ralph

2015-06-01

Male twin gestations exhibit higher incidence of fetal morbidity and mortality than singleton gestations. From an evolutionary perspective, the relatively high rates of infant and child mortality among male twins born into threatening environments reduce the fitness of these gestations, making them more vulnerable to fetal loss. Women do not perceive choosing to spontaneously abort gestations although the outcome may result from estimates, made without awareness, of the risks of continuing a pregnancy. Here, we examine whether the non-conscious decisional biology of gestation can be linked to conscious risk aversion. We test this speculation by measuring the association between household surveys in Sweden that gauge financial risk aversion in the population and the frequency of twins among live male births. We used time-series regression methods to estimate our suspected associations and Box-Jenkins modeling to ensure that autocorrelation did not confound the estimation or reduce its efficiency. We found, consistent with theory, that financial risk aversion in the population correlates inversely with the odds of a twin among Swedish males born two months later. The odds of a twin among males fell by approximately 3.5% two months after unexpectedly great risk aversion in the population. This work implies that shocks that affect population risk aversion carry implications for fetal loss in vulnerable twin pregnancies.

Loss aversion and duration of residence

Directory of Open Access Journals (Sweden)

Philip S. Morrison

2016-10-01

Full Text Available Background: Studies of internal migration ask who moves, why they move, and what are the consequences - to themselves, their origin, and their destination. By contrast, studies of those who stay for very long durations are less common, despite the fact that most people move relatively infrequently. Objective: We argue that staying is the dominant, preferred state and that moving is simply an adjustment toward a desired state of stability (or equilibrium. The core of our argument, already recognized in the literature, is that migration is risky. However, we extend the argument to loss aversion as developed within prospect theory. Prospect theory posits that existing possessions, including the dwelling and existing commodities, are attributed a value well beyond their purchase price and that this extends the average period of staying among the loss-averse. Methods: Applying prospect theory has several challenges, including measurement of the reference point and potential degrees of gain and loss households face in deciding to change residence, as well as their own degree of loss aversion. The growing number of large panel sets should make it possible to estimate the degree to which endowment effects are likely to extend durations of residence as predicted by prospect theory. Conclusions: Rational expectations models of mobility focus on the changes in the level of consumption of residential services. By contrast, prospect theory focuses on potential gains and losses relative to the existing dwelling - the reference point. As we confront increasing durations of residence in contemporary society, an application of prospect theory is likely to yield important advantages over existing models of mobility and staying.

Aversion to ambiguity and willingness to take risks affect therapeutic decisions in managing atrial fibrillation for stroke prevention: results of a pilot study in family physicians

Directory of Open Access Journals (Sweden)

Raptis S

2017-09-01

Full Text Available Stavroula Raptis,1,* Jia Ning Chen,2,* Florencia Saposnik,2 Roman Pelyavskyy,2 Andrew Liuni,3 Gustavo Saposnik2,4 On behalf of the Stroke Outcomes Research Canada Working Group (SORCan- www.sorcan.ca 1Applied Health Research Centre, Li Ka Shing Knowledge Institute, 2Stroke Outcomes and Decision Neuroscience Research Unit, Department of Medicine, St. Michael’s Hospital, University of Toronto, Toronto, 3Medical Department, Boehringer Ingelheim (Canada Ltd., Burlington, ON, Canada; 4Neuroeconomics and Decision Neuroscience, Department of Economics, University of Zurich, Zurich, Switzerland *These authors contributed equally to this work Background: Anticoagulation is the therapeutic paradigm for stroke prevention in patients with atrial fibrillation (AF. It is unknown how physicians make treatment decisions in primary stroke prevention for patients with AF. Objectives: To evaluate the association between family physicians’ risk preferences (aversion risk and ambiguity and therapeutic recommendations (anticoagulation in the management of AF for primary stroke prevention by applying concepts from behavioral economics. Methods: Overall, 73 family physicians participated and completed the study. Our study comprised seven simulated case vignettes, three behavioral experiments, and two validated surveys. Behavioral experiments and surveys incorporated an economic framework to determine risk preferences and biases (e.g., ambiguity aversion, willingness to take risks. The primary outcome was making the correct decision of anticoagulation therapy. Secondary outcomes included medical errors in the management of AF for stroke prevention. Results: Overall, 23.3% (17/73 of the family physicians elected not to escalate the therapy from antiplatelets to anticoagulation when recommended by best practice guidelines. A total of 67.1% of physicians selected the correct therapeutic options in two or more of the three simulated case vignettes. Multivariate

Social interaction with non-averse group-mates modifies a learned food aversion in single- and mixed-species groups of tamarins (Saguinus fuscicollis and S. labiatus).

Science.gov (United States)

Prescott, M J; Buchanan-Smith, H M; Smith, A C

2005-04-01

For social species, being a member of a cohesive group and performing activities as a coordinated unit appear to provide a mechanism for the efficient transmission of information about food. Social learning about food palatability was investigated in two captive primates, Saguinus fuscicollis and S. labiatus, which form stable and cohesive mixed-species groups in the wild. We explored whether an induced food aversion toward a preferred food is modified during and after social interaction with non-averse conspecifics or congeners. Sets of intra- and interspecific pairs were presented with two foods, one of which was considered distasteful by one of the pairs (the other was palatable), and their behavior was compared pre-interaction, during interaction, and post-interaction. For the aversely-conditioned individuals of both species, the change in social context corresponded to a change in their preference for the food that they considered unpalatable, regardless of whether they had interacted with a conspecific or congeneric pair, and the change in food preference was maintained post-interaction. In a control condition, in which averse individuals did not have the opportunity to interact with non-averse animals, S. fuscicollis sampled the preferred food, but not as quickly as when given the opportunity to interact. We conclude that the social learning demonstrated here may allow individual tamarins to track environmental change, such as fruit ripening, more efficiently than asocial learning alone, because social learners can more quickly and safely focus on appropriate behavior by sharing up-to-date foraging information. Furthermore, since the behavior of congeners, as well as conspecifics, acts to influence food choice in a more adaptive direction, social learning about food palatability may be an advantage of mixed-species group formation to tamarins of both species. Copyright 2005 Wiley-Liss, Inc

Measuring Risk Aversion for Nuclear Power Plant Accident: Results of Contingent Valuation Survey in Korea

International Nuclear Information System (INIS)

Lee, Sang Hun; Kang, Hyun Gook

2015-01-01

Within the evaluation of the external cost of nuclear energy, the estimation of the external cost of nuclear power plant (NPP) severe accident is one of the major topics to be addressed. For the evaluation of the external cost of NPP severe accident, the effect of public risk averse behavior against the group accidents, such as NPP accident, dam failure, must be addressed. Although the equivalent fatalities from a single group accident are not common and its risk is very small compared to other accidents, people perceive the group accident more seriously. In other words, people are more concerned about low probability/high consequence events than about high probability/low consequence events having the same mean damage. One of the representative method to integrate the risk aversion in the external costs of severe nuclear reactor accidents was developed by Eeckoudt et al., and he used the risk aversion coefficient, mainly based on the analysis of financial risks in the stock markets to evaluate the external cost of nuclear severe accident. However, the use of financial risk aversion coefficient to nuclear severe accidents is not appropriate, because financial risk and nuclear severe accident risk are entirely different. In this paper, the individual-level survey was conducted to measure the risk aversion coefficient and estimate the multiplication factor to integrate the risk aversion in the external costs of NPP severe accident. This study propose an integrated framework on estimation of the external cost associated with severe accidents of NPP considering public risk aversion behavior. The theoretical framework to estimate the risk aversion coefficient/multiplication factor and to assess economic damages from a hypothetical NPP accident was constructed. Based on the theoretical framework, the risk aversion coefficient can be analyzed by conducting public survey with a carefully designed lottery questions. Compared to the previous studies on estimation of the

Measuring Risk Aversion for Nuclear Power Plant Accident: Results of Contingent Valuation Survey in Korea

Energy Technology Data Exchange (ETDEWEB)

Lee, Sang Hun; Kang, Hyun Gook [KAIST, Daejeon (Korea, Republic of)

2015-05-15

Within the evaluation of the external cost of nuclear energy, the estimation of the external cost of nuclear power plant (NPP) severe accident is one of the major topics to be addressed. For the evaluation of the external cost of NPP severe accident, the effect of public risk averse behavior against the group accidents, such as NPP accident, dam failure, must be addressed. Although the equivalent fatalities from a single group accident are not common and its risk is very small compared to other accidents, people perceive the group accident more seriously. In other words, people are more concerned about low probability/high consequence events than about high probability/low consequence events having the same mean damage. One of the representative method to integrate the risk aversion in the external costs of severe nuclear reactor accidents was developed by Eeckoudt et al., and he used the risk aversion coefficient, mainly based on the analysis of financial risks in the stock markets to evaluate the external cost of nuclear severe accident. However, the use of financial risk aversion coefficient to nuclear severe accidents is not appropriate, because financial risk and nuclear severe accident risk are entirely different. In this paper, the individual-level survey was conducted to measure the risk aversion coefficient and estimate the multiplication factor to integrate the risk aversion in the external costs of NPP severe accident. This study propose an integrated framework on estimation of the external cost associated with severe accidents of NPP considering public risk aversion behavior. The theoretical framework to estimate the risk aversion coefficient/multiplication factor and to assess economic damages from a hypothetical NPP accident was constructed. Based on the theoretical framework, the risk aversion coefficient can be analyzed by conducting public survey with a carefully designed lottery questions. Compared to the previous studies on estimation of the

Impact of Risk Aversion on Price and Quality Decisions under Demand Uncertainty via the CARA Utility Function

Directory of Open Access Journals (Sweden)

Qinqin Li

2014-01-01

Full Text Available This paper investigates optimal price and quality decisions of a manufacturer-retailer supply chain under demand uncertainty, in which players are both risk-averse decision makers. The manufacturer determines the wholesale price and quality of the product, and the retailer determines the retail price. By means of game theory, we employ the constant absolute risk aversion (CARA function to analyze two different supply chain structures, that is, manufacturer Stackelberg model (MS and retailer Stackelberg model (RS. We then analyze the results to explore the effects of risk aversion of the manufacturer and the retailer upon the equilibrium decisions. Our results imply that both the risk aversion of the manufacturer and the retailer play an important role in the price and quality decisions. We find that, in general, in MS and RS models, the optimal wholesale price and quality decrease with the risk aversion of the manufacturer but increase with the risk aversion of the retailer, while the retail price decreases with the risk aversion of the manufacturer as well as the retailer. We also examine the impact of quality cost coefficient on the optimal decisions. Finally, numerical examples are presented to illustrate the different degree of effects of players’ risk aversion on equilibrium results and to compare results in different models considered.

Role for the Rostromedial Tegmental Nucleus in Signaling the Aversive Properties of Alcohol.

Science.gov (United States)

Glover, Elizabeth J; McDougle, Molly J; Siegel, Griffin S; Jhou, Thomas C; Chandler, L Judson

2016-08-01

While the rewarding effects of alcohol contribute significantly to its addictive potential, it is becoming increasingly appreciated that alcohol's aversive properties also play an important role in the propensity to drink. Despite this, the neurobiological mechanism for alcohol's aversive actions is not well understood. The rostromedial tegmental nucleus (RMTg) was recently characterized for its involvement in aversive signaling and has been shown to encode the aversive properties of cocaine, yet its involvement in alcohol's aversive actions have not been elucidated. Adult male and female Long-Evans rats underwent conditioned taste aversion (CTA) procedures where exposure to a novel saccharin solution was paired with intraperitoneal administration of saline, lithium chloride (LiCl), or ethanol (EtOH). Control rats underwent the same paradigm except that drug and saccharin exposure were explicitly unpaired. Saccharin consumption was measured on test day in the absence of drug administration, and rats were sacrificed 90 to 105 minutes following access to saccharin. Brains were subsequently harvested and processed for cFos immunohistochemistry. The number of cFos-labeled neurons was counted in the RMTg and the lateral habenula (LHb)-a region that sends prominent glutamatergic input to the RMTg. In rats that received paired drug and saccharin exposure, EtOH and LiCl induced significant CTA compared to saline to a similar degree in males and females. Both EtOH- and LiCl-induced CTA significantly enhanced cFos expression in the RMTg and LHb but not the hippocampus. Similar to behavioral measures, no significant effect of sex on CTA-induced cFos expression was observed. cFos expression in both the RMTg and LHb was significantly correlated with CTA magnitude with greater cFos being associated with more pronounced CTA. In addition, cFos expression in the RMTg was positively correlated with LHb cFos. These data suggest that the RMTg and LHb are involved in the expression of

Personality, risk aversion and speeding: an empirical investigation.

Science.gov (United States)

Greaves, Stephen P; Ellison, Adrian B

2011-09-01

Evidence suggests that in addition to demographics, there are strong relationships between facets of drivers' personality (e.g., aggression, thrill-seeking, altruism), aversion to risk and driving behaviour, particularly speeding. However, evidence is muted by the reliance on self-reported driving behaviour, which is thought to not accurately reflect actual driving behaviour. This paper reports on a study of 133 drivers in Sydney, who were asked to complete a short survey to develop their personality and risk aversion profiles and self-reported speeding behaviour. A Global Positioning System (GPS) device was then installed in their vehicle for several weeks as part of a major investigation of driving behaviour from which empirical measures of speeding are derived. Among the most pertinent findings are: (1) the tendency for drivers to both under and over-estimate their propensity to speed, (2) significant heterogeneity in speeding with a small, but notable number of drivers exceeding the limit for more than 20 percent of the distance driven, (3) weak relationships between the personality/risk-aversion measures and actual speeding, and (4) the suggestion that different personality traits appear to influence behaviour in different situations both from self-reported and actual speeding behaviour. Copyright © 2011 Elsevier Ltd. All rights reserved.

Loss Aversion, Adaptive Beliefs, and Asset Pricing Dynamics

Directory of Open Access Journals (Sweden)

Kamal Samy Selim

2015-01-01

Full Text Available We study asset pricing dynamics in artificial financial markets model. The financial market is populated with agents following two heterogeneous trading beliefs, the technical and the fundamental prediction rules. Agents switch between trading rules with respect to their past performance. The agents are loss averse over asset price fluctuations. Loss aversion behaviour depends on the past performance of the trading strategies in terms of an evolutionary fitness measure. We propose a novel application of the prospect theory to agent-based modelling, and by simulation, the effect of evolutionary fitness measure on adaptive belief system is investigated. For comparison, we study pricing dynamics of a financial market populated with chartists perceive losses and gains symmetrically. One of our contributions is validating the agent-based models using real financial data of the Egyptian Stock Exchange. We find that our framework can explain important stylized facts in financial time series, such as random walk price behaviour, bubbles and crashes, fat-tailed return distributions, power-law tails in the distribution of returns, excess volatility, volatility clustering, the absence of autocorrelation in raw returns, and the power-law autocorrelations in absolute returns. In addition to this, we find that loss aversion improves market quality and market stability.

Sensitivity of the brain to loss aversion during risky gambles.

Science.gov (United States)

Dreher, Jean-Claude

2007-07-01

Little is known about the neural systems that subserve human loss aversion. A recent neuroimaging study by Tom, Poldrack and colleagues reports that this pattern of behaviour is directly tied to the greater sensitivity of the brain to potential losses compared with potential gains and uncovers a brain network whose activity increases with potential gains and decreases with potential losses. These results challenge the common view that loss aversion engages a distinct emotion-related brain network (e.g. amygdala and insula).

On Loss Aversion in Capuchin Monkeys

Science.gov (United States)

Silberberg, Alan; Roma, Peter G.; Huntsberry, Mary E.; Warren-Boulton, Frederick R.; Sakagami, Takayuki; Ruggiero, Angela M.; Suomi, Stephen J.

2008-01-01

Chen, Lakshminarayanan, and Santos (2006) claim to show in three choice experiments that monkeys react rationally to price and wealth shocks, but, when faced with gambles, display hallmark, human-like biases that include loss aversion. We present three experiments with monkeys and humans consistent with a reinterpretation of their data that…

Optimal Ordering Policy of a Risk-Averse Retailer Subject to Inventory Inaccuracy

Directory of Open Access Journals (Sweden)

Lijing Zhu

2013-01-01

Full Text Available Inventory inaccuracy refers to the discrepancy between the actual inventory and the recorded inventory information. Inventory inaccuracy is prevalent in retail stores. It may result in a higher inventory level or poor customer service. Earlier studies of inventory inaccuracy have traditionally assumed risk-neutral retailers whose objective is to maximize expected profits. We investigate a risk-averse retailer within a newsvendor framework. The risk aversion attitude is measured by conditional-value-at-risk (CVaR. We consider inventory inaccuracy stemming both from permanent shrinkage and temporary shrinkage. Two scenarios of reducing inventory shrinkage are presented. In the first scenario, the retailer conducts physical inventory audits to identify the discrepancy. In the second scenario, the retailer deploys an automatic tracking technology, radiofrequency identification (RFID, to reduce inventory shrinkage. With the CVaR criterion, we propose optimal policies for the two scenarios. We show monotonicity between the retailer’s ordering policy and his risk aversion degree. A numerical analysis provides managerial insights for risk-averse retailers considering investing in RFID technology.

Conditioned taste aversion to ethanol in a social context: impact of age and sex.

Science.gov (United States)

Morales, Melissa; Schatz, Kelcie C; Anderson, Rachel I; Spear, Linda P; Varlinskaya, Elena I

2014-03-15

Given that human adolescents place a high value on social interactions-particularly while consuming alcohol-the current study utilized a novel social drinking paradigm to examine rewarding and aversive properties of ethanol in non-water deprived rats that were housed and tested in groups of five same-sex littermates. On postnatal day P34 (adolescents) or P69 (adults), rats were habituated to the testing apparatus for 30 min. On the next day, animals were placed into the test apparatus and given 30 min access to a supersaccharin solution (3% sucrose; 0.125% saccharin), followed immediately by an intraperitoneal injection of ethanol (0, 0.25, 0.5, 1.0, 1.5 g/kg). Subsequent intake of the supersacharrin solution was assessed on three consecutive test days. Adolescent males were less sensitive to ethanol's aversive effects than adult males, with adolescent males maintaining an aversion on all three test days only at the 1.5 g/kg dose, whereas adults demonstrated aversions across test days to 1 and 1.5 g/kg. Adolescent females maintained aversions to 1 and 1.5 g/kg across days, whereas adult females continued to show an aversion to the 1.5 g/kg dose only. These opposite patterns of sensitivity that emerged among males and females at each age in the propensity to maintain an ethanol-induced taste aversion under social conditions may contribute to age- and sex-related differences in ethanol intake. Testing in social groups may be useful for future work when studying rodent models of adolescent alcohol use given the importance that human adolescents place on drinking in social settings. Copyright © 2014 Elsevier B.V. All rights reserved.

Role of the area postrema in radiation-induced taste aversion learning and emesis in cats

International Nuclear Information System (INIS)

Rabin, B.M.; Hunt, W.A.; Chedester, A.L.; Lee, J.

1986-01-01

The role of the area postrema in radiation-induced emesis and taste aversion learning and the relationship between these behaviors were studied in cats. The potential involvement of neural factors which might be independent of the area postrema was minimized by using low levels of ionizing radiation (100 rads at a dose rate of 40 rads/min) to elicit a taste aversion, and by using body-only exposures (4500 and 6000 rads at 450 rads/min) to produce emesis. Lesions of the area postrema disrupted both taste aversion learning and emesis following irradiation. These results, which indicate that the area postrema is involved in the mediation of both radiation-induced emesis and taste aversion learning in cats under these experimental conditions, are interpreted as being consistent with the hypotheses that similar mechanisms mediate both responses to exposure to ionizing radiation, and that the taste aversion learning paradigm can therefore serve as a model system for studying radiation-induced emesis

State-dependent interaction in the antihistamine-induced disruption of a radiation-induced conditioned taste aversion

International Nuclear Information System (INIS)

Rabin, B.M.; Hunt, W.A.; Lee, J.

1982-01-01

Two experiments were run to evaluate the possibility that injection of antihistamine can produce a state-dependent acquisition of a radiation-induced conditioned taste aversion. In the first experiment, pretreating rats with the antihistamine chlorpheniramine maleate prior to their initial exposure to sucrose and to low-level irradiation on the conditioning day did not prevent the acquisition of a taste aversion to sucrose when the antihistamine was also administered prior to a subsequent preference test. In the second experiment, rats were both conditioned and tested for a radiation-induced aversion in a drug-free state. Under these condtions, the rats continued to show an aversion to sucrose despite pretreating them with chlorpheniramine prior to irradiation. Since rats conditioned under the antihistamine do not show the radiation-induced conditioned taste aversion when tested for sucrose preference in a nondrug state, it would seem that pretreating rats with an antihistamine prior to conditioning affects only the retrieval of the previously learned response and not its acquisition

Risk Aversion and the Value of Information.

Science.gov (United States)

Eeckhoudt, Louis; Godfroid, Phillippe

2000-01-01

Explains why risk aversion does not always induce a greater information value, but instead may induce a lower information value when increased. Presents a basic model defining the concept of perfect information value and providing a numerical illustration. Includes references. (CMK)

Medial amygdala lesions selectively block aversive Pavlovian-instrumental transfer in rats.

Directory of Open Access Journals (Sweden)

Margaret Grace McCue

2014-09-01

Full Text Available Pavlovian conditioned stimuli (CSs play an important role in the reinforcement and motivation of instrumental active avoidance (AA. Conditioned threats can also invigorate ongoing AA responding (aversive Pavlovian-instrumental transfer or PIT. The neural circuits mediating AA are poorly understood, although lesion studies suggest that lateral, basal and central amygdala nuclei, as well as infralimbic prefrontal cortex, make key, and sometimes opposing, contributions. We recently completed an extensive analysis of brain c-Fos expression in good vs. poor avoiders following an AA test (Martinez et al 2013, Learning and Memory. This analysis identified medial amygdala (MeA as a potentially important region for Pavlovian motivation of instrumental actions. MeA is known to mediate defensive responding to innate threats as well as social behaviors, but its role in mediating aversive Pavlovian-instrumental interactions is unknown. We evaluated the effect of MeA lesions on Pavlovian conditioning, Sidman two-way AA conditioning (shuttling and aversive PIT in rats. Mild footshocks served as the unconditioned stimulus in all conditioning phases. MeA lesions had no effect on AA but blocked the expression of aversive PIT and 22 kHz ultrasonic vocalizations in the AA context. Interestingly, MeA lesions failed to affect Pavlovian freezing to discrete threats but reduced freezing to contextual threats when assessed outside of the AA chamber. These findings differentiate MeA from lateral and central amygdala, as lesions of these nuclei disrupt Pavlovian freezing and aversive PIT, but have opposite effects on AA performance. Taken together, these results suggest that MeA plays a selective role in the motivation of instrumental avoidance by general or uncertain Pavlovian threats.

Does Market Experience Attenuate Risk Aversion? Evidence from Landed Farm Households in Ethiopia

NARCIS (Netherlands)

Melesse, Mequanint Biset; Cecchi, Francesco

2017-01-01

Risk preferences are important drivers of many relevant economic decisions of farm households. High risk aversion is a well-known trigger of "poverty traps" for farm households in developing countries. This paper analyzes the effect of market experience on risk aversion for a relatively large sample

Small- and large-stakes risk aversion: implications of concavity calabration for decision theory

NARCIS (Netherlands)

Cox, J.C.; Sadiraj, V.

2006-01-01

A growing literature reports the conclusions that: (a) expected utility theory does not provide a plausible theory of risk aversion for both small-stakes and large-stakes gambles; and (b) this decision theory should be replaced with an alternative theory characterized by loss aversion. This paper

Does Market Experience Attenuate Risk Aversion? Evidence from Landed Farm Households in Ethiopia

NARCIS (Netherlands)

Melesse, Mequanint B.; Cecchi, Francesco

2017-01-01

Risk preferences are important drivers of many relevant economic decisions of farm households. High risk aversion is a well-known trigger of "poverty traps" for farm households in developing countries. This paper analyzes the effect of market experience on risk aversion for a relatively large

Mangifera indica L. extract (Vimang improves the aversive memory in spinocerebellar ataxia type 2 transgenic mice.

Directory of Open Access Journals (Sweden)

Natasha Maurmann

2014-06-01

Full Text Available Context: The spinocerebellar ataxia type 2 (SCA-2 is a progressive neurodegenerative disorder without specific therapy identified, and it is related to the loss of function in the cerebellum, mitochondrial dysfunction, oxidative stress and neurotoxic processes. Scientific evidence indicates that Mangifera indica L. aqueous extract (MiE and its major constituent (mangiferin display antioxidant, anti-inflammatory and neuroprotective actions. Aims: To investigate the MiE and mangiferin effects on behavioral outcomes of neurological function in SCA-2 transgenic mice. Methods: The SCA-2 transgenic mice were daily and orally administered during 12 months with MiE (10, 50, and 100 mg/kg, mangiferin (10 mg/kg or vehicle. It was evaluated locomotion (open-field, aversive memory (inhibitory avoidance and declarative memory (object recognition. To explore possible cellular mechanisms underlying the in vivo effects was also evaluated their effects on nerve grow factor (NGF and tumor necrosis factor-α (TNF-α levels in the human glioblastoma cell line U138-MG supernatant. Results: MiE administration did not affect the object recognition memory, but mangiferin did. The natural extract improved selectively the aversive memory in SCA-2 mice, indicating that MiE can affect behavioral parameters regarding fear-related memory. MiE also induced a significant increase in supernatant levels of NGF and TNF-α in vitro in human U138-MG glioblastoma cells. Conclusions: The results suggest that MiE enhances the aversive memory through a mechanism that might involve an increase in neurotrophin and cytokine levels. These findings constitute the basis for the use of the natural extract in the prevention/treatment of memory deficits in SCA-2.

A psychological law of inertia and the illusion of loss aversion

Directory of Open Access Journals (Sweden)

David Gal

2006-07-01

Full Text Available The principle of loss aversion is thought to explain a wide range of anomalous phenomena involving tradeoffs between losses and gains. In this article, I show that the anomalies loss aversion was introduced to explain --- the risky bet premium, the endowment effect, and the status-quo bias --- are characterized not only by a loss/gain tradeoff, but by a tradeoff between the status-quo and change; and, that a propensity towards the status-quo in the latter tradeoff is sufficient to explain these phenomena. Moreover, I show that two basic psychological principles --- (1 that motives drive behavior; and (2 that preferences tend to be fuzzy and ill-defined --- imply the existence of a robust and fundamental propensity of this sort. Thus, a loss aversion principle is rendered superfluous to an account of the phenomena it was

Five-year-olds do not show ambiguity aversion in a risk and ambiguity task with physical objects.

Science.gov (United States)

Li, Rosa; Roberts, Rachel C; Huettel, Scott A; Brannon, Elizabeth M

2017-07-01

Ambiguity aversion arises when a decision maker prefers risky gambles with known probabilities over equivalent ambiguous gambles with unknown probabilities. This phenomenon has been consistently observed in adults across a large body of empirical work. Evaluating ambiguity aversion in young children, however, has posed methodological challenges because probabilistic representations appropriate for adults might not be understood by young children. Here, we established a novel method for representing risk and ambiguity with physical objects that overcomes previous methodological limitations and allows us to measure ambiguity aversion in young children. We found that individual 5-year-olds exhibited consistent choice preferences and, as a group, exhibited no ambiguity aversion in a task that evokes ambiguity aversion in adults. Across individuals, 5-year-olds exhibited greater variance in ambiguity preferences compared with adults tested under similar conditions. This suggests that ambiguity aversion is absent during early childhood and emerges over the course of development. Copyright © 2017 Elsevier Inc. All rights reserved.

Individual Differences in Loss Aversion: Conscientiousness Predicts How Life Satisfaction Responds to Losses Versus Gains in Income.

Science.gov (United States)

Boyce, Christopher J; Wood, Alex M; Ferguson, Eamonn

2016-04-01

Loss aversion is considered a general pervasive bias occurring regardless of the context or the person making the decision. We hypothesized that conscientiousness would predict an aversion to losses in the financial domain. We index loss aversion by the relative impact of income losses and gains on life satisfaction. In a representative German sample (N = 105,558; replicated in a British sample, N = 33,848), with conscientiousness measured at baseline, those high on conscientiousness have the strongest reactions to income losses, suggesting a pronounced loss aversion effect, whereas for those moderately unconscientious, there is no loss aversion effect. Our research (a) provides the first evidence of personality moderation of any loss aversion phenomena, (b) supports contextual perspectives that both personality and situational factors need to be examined in combination, (c) shows that the small but robust relationship between income and life satisfaction is driven primarily by a subset of people experiencing highly impactful losses. © 2016 by the Society for Personality and Social Psychology, Inc.

Averse to Initiative: Risk Management’s Effect on Mission Command

Science.gov (United States)

2017-05-25

Master’s Thesis 3. DATES COVERED (From - To) JUN 2016 – MAY 2017 4. TITLE AND SUBTITLE Averse to Initiative: Risk Management’s Effect on Mission...decision weights and potential implications of educating leaders with Prospect Theory . Prospect Theory sheds light on how to look at loss and opportunity...the gain–causing risk aversion. Leaders educated in how to analyze a problem using Prospect Theory can rationally approach gains and losses. For the

Fairness concerns and risk aversion on recycle pricing strategies: Implications for environmentally friendly supply chains

OpenAIRE

He, Jianhong; Zhang, Lei; Lu, Binbin; Li, Lin

2018-01-01

This paper studies the pricing strategy in the closed-loop supply chain with Nash bargaining when considering fairness concerns and risk aversion. Mainly, the authors argue that behavioral factors (i.e., fairness concern and risk aversion) should be introduced into pricing process. They consider three different pricing models: the first is that both manufacturer and retailer have fairness concern; the second is both manufacturer and retailer have risk aversion and the final is manufacturer ha...

Strain-dependent sex differences in the effects of alcohol on cocaine-induced taste aversions.

Science.gov (United States)

Jones, Jermaine D; Busse, Gregory D; Riley, Anthony L

2006-04-01

Research using the conditioned taste aversion procedure has reported that a cocaine/alcohol combination induces a significantly stronger taste aversion than either cocaine or alcohol alone. These findings suggest that the co-administration of alcohol intensifies the aversive effects of cocaine. Although the behavioral interaction of cocaine and alcohol is well established, little is known about how the effects of this drug combination might be modulated by a variety of subject variables. The current investigation addressed this by assessing if the ability of alcohol to potentiate cocaine-induced taste aversions is dependent upon the strain and/or sex of the subject. In this series of studies, male and female rats of Long-Evans (Experiment 1) and Sprague-Dawley (Experiment 2) descent were given limited access to a novel saccharin solution to drink and were then injected with either vehicle, cocaine (20 mg/kg), alcohol (0.56 g/kg) or the alcohol/cocaine combination. This procedure was repeated every fourth day for a total of four conditioning trials. All subjects were then compared on an Aversion Test that followed the fourth conditioning cycle. In three of the groups tested (male Long-Evans; male and female Sprague-Dawley), cocaine induced a significant taste aversion that was unaffected by the co-administration of alcohol. However, in female Long-Evans subjects, the addition of alcohol significantly strengthened the avoidance of the saccharin solution. Although the effects of alcohol on cocaine-induced taste aversions are dependent upon an interaction of sex and strain, the basis for this SexxStrain interaction is not known. That such an interaction is evident suggests that attention to such factors in assessing the effects of drug combinations is important to understanding the likelihood of the use and abuse of such drugs.

OBSESSIVE COMPULSIVE NEUROSIS: TREATMENT OF 28 CASES BY BEHAVIOUR THERAPY

OpenAIRE

Pradhan, P.V.; Ayyar, K.S.; Munjal, P.D.; Gopalani, J.H.; Mundra, A.V.; Doshi, Jyoti; Bagadia, V.N.

1984-01-01

SUMMARY Twenty-eight cases of obsessive compulsive neurosis were treated with a behaviour therapy package and good results were obtained in 15 (53.6%). Relaxation, thought-stopping, implosion, modelling, response prevention, electrical aversion and positive reinforcement wei; the techniques employed. Chronicity, previous treatments, follow-up data, drop-outs and the use of behaviour therapy in our setting are discussed in this paper.

Radiation-induced taste aversion: effects of radiation exposure level and the exposure-taste interval

International Nuclear Information System (INIS)

Spector, A.C.; Smith, J.C.; Hollander, G.R.

1986-01-01

Radiation-induced taste aversion has been suggested to possibly play a role in the dietary difficulties observed in some radiotherapy patients. In rats, these aversions can still be formed even when the radiation exposure precedes the taste experience by several hours. This study was conducted to examine whether increasing the radiation exposure level could extend the range of the exposure-taste interval that would still support the formation of a taste aversion. Separate groups of rats received either a 100 or 300 R gamma-ray exposure followed 1, 3, 6, or 24 h later by a 10-min saccharin (0.1% w/v) presentation. A control group received a sham exposure followed 1 h later by a 10-min saccharin presentation. Twenty-four hours following the saccharin presentation all rats received a series of twelve 23-h two-bottle preference tests between saccharin and water. The results indicated that the duration of the exposure-taste interval plays an increasingly more important role in determining the initial extent of the aversion as the dose decreases. The course of recovery from taste aversion seems more affected by dose than by the temporal parameters of the conditioning trial

Inequity aversion and the evolution of cooperation

Science.gov (United States)

Ahmed, Asrar; Karlapalem, Kamalakar

2014-02-01

Evolution of cooperation is a widely studied problem in biology, social science, economics, and artificial intelligence. Most of the existing approaches that explain cooperation rely on some notion of direct or indirect reciprocity. These reciprocity based models assume agents recognize their partner and know their previous interactions, which requires advanced cognitive abilities. In this paper we are interested in developing a model that produces cooperation without requiring any explicit memory of previous game plays. Our model is based on the notion of inequity aversion, a concept introduced within behavioral economics, whereby individuals care about payoff equality in outcomes. Here we explore the effect of using income inequality to guide partner selection and interaction. We study our model by considering both the well-mixed and the spatially structured population and present the conditions under which cooperation becomes dominant. Our results support the hypothesis that inequity aversion promotes cooperative relationship among nonkin.

Aversive Life Events Enhance Human Freezing Responses

NARCIS (Netherlands)

Hagenaars, M.A.; Stins, J.F.; Roelofs, K.

2012-01-01

In the present study, we investigated the effect of prior aversive life events on freezing-like responses. Fifty healthy females were presented neutral, pleasant, and unpleasant images from the International Affective Picture System while standing on a stabilometric platform and wearing a polar band

Aversive life events enhance human freezing responses

NARCIS (Netherlands)

Hagenaars, M.A.; Stins, J.F.; Roelofs, K.

2012-01-01

In the present study, we investigated the effect of prior aversive life events on freezing-like responses. Fifty healthy females were presented neutral, pleasant, and unpleasant images from the International Affective Picture System while standing on a stabilometric platform and wearing a polar band

Risk Aversion and Skewness Preference: a comment

NARCIS (Netherlands)

G.T. Post (Thierry); P. van Vliet (Pim)

2003-01-01

textabstractEmpirically, co-skewness of asset returns seems to explain a substantial part of the cross-sectional variation of mean return not explained by beta. Thisfinding is typically interpreted in terms of a risk averse representativeinvestor with a cubic utility function. This comment questions

Attenuation of radiation- and drug-induced conditioned taste aversions following area postrema lesions in the rat

International Nuclear Information System (INIS)

Rabin, B.M.; Hunt, W.A.; Lee, J.

1983-01-01

The effects of lesions of the area postrema on the acquisition of radiation- and drug-induced (histamine and lithium chloride) conditioned taste aversions were investigated. The results indicated that area postrema lesions caused a significant attenuation of the aversion produced by pairing a novel sucrose solution with radiation (100 rad) or drug injection. Further, the area postrema lesions produced a similar level of attenuation of the taste aversion in all three treatment conditions. The results are discussed in terms of the implications of this finding for defining the mechanisms by which exposure to ionizing radiation can lead to the acquisition of a conditioned taste aversion

Conditioned taste aversion: modulation by 5-HT receptor activity and corticosterone

DEFF Research Database (Denmark)

Boris, Gorzalka; Hanson, Laura; Harrington, J

2003-01-01

Two experiments were designed to elucidate the involvement of the hypothalamic-pituitary-adrenal axis and the 5-hydroxytryptamine (5-HT) system in the acquisition of lithium chloride-conditioned taste aversion. In Experiment 1, rats were administered either vehicle or 50 mg/kg nefazodone daily fo......, corticosterone-treated animals required more trials to reach extinction. These results suggest the involvement of both the 5-HT system and the hypothalamic-pituitary-adrenal axis in lithium chloride-conditioned taste aversion....

Leverage Aversion and Risk Parity

DEFF Research Database (Denmark)

Asness, Clifford; Frazzini, Andrea; Heje Pedersen, Lasse

2012-01-01

The authors show that leverage aversion changes the predictions of modern portfolio theory: Safer assets must offer higher risk-adjusted returns than riskier assets. Consuming the high risk-adjusted returns of safer assets requires leverage, creating an opportunity for investors with the ability...... to apply leverage. Risk parity portfolios exploit this opportunity by equalizing the risk allocation across asset classes, thus overweighting safer assets relative to their weight in the market portfolio....

To answer or not to answer? A field test of loss aversion

OpenAIRE

Michał Krawczyk

2011-01-01

This study is a field experiment on loss aversion. The framing of scoring rules was differentiated in two exams at the University of Warsaw, with only half the students facing explicit penalty points in the case of giving an incorrect answer. Loss aversion predicts that less risk will be taken (less questions will be answered) when losses are possible but in fact, no treatment effect was observed.

Attenuation and cross-attenuation in taste aversion learning in the rat: Studies with ionizing radiation, lithium chloride and ethanol

International Nuclear Information System (INIS)

Rabin, B.M.; Hunt, W.A.; Lee, J.

1988-01-01

The preexposure paradigm was utilized to evaluate the similarity of ionizing radiation, lithium chloride and ethanol as unconditioned stimuli for the acquisition of a conditioned taste aversion. Three unpaired preexposures to lithium chloride (3.0 mEq/kg, IP) blocked the acquisition of a taste aversion when a novel sucrose solution was paired with either the injection of the same dose of lithium chloride or exposure to ionizing radiation (100 rad). Similar pretreatment with radiation blocked the acquisition of a radiation-induced aversion, but had no effect on taste aversions produced by lithium chloride (3.0 or 1.5 mEq/kg). Preexposure to ethanol (4 g/kg, PO) disrupted the acquisition of an ethanol-induced taste aversion, but not radiation- or lithium chloride-induced aversions. In contrast, preexposure to either radiation or lithium chloride attenuated an ethanol-induced taste aversion in intact rats, but not in rats with lesions of the area postrema. The results are discussed in terms of relationships between these three unconditioned stimuli and in terms of implications of these results for understanding the nature of the proximal unconditioned stimulus in taste aversion learning

Aversion learning can reduce meal size without taste avoidance in rats.

Science.gov (United States)

Tracy, Andrea L; Schurdak, Jennifer D; Chambers, James B; Benoit, Stephen C

2016-03-01

Nausea and aversive food responses are commonly reported following bariatric surgery, along with post-surgical reduction in meal size. This study investigates whether a meal size limit can be conditioned by associating large meals with aversive outcomes. In rats, the intake of meals exceeding a pre-defined size threshold was paired with lithium chloride-induced gastric illness, and the effects on self-determined food intakes and body weight were measured. Rats given LiCl contingent on the intake of a large meal learned to reliably reduce intake below this meal size threshold, while post-meal saline or LiCl before meals did not change meal size. It was further demonstrated that this is not a conditioned taste aversion and that this effect transferred to foods not explicitly trained. Finally, when rats received LiCl following all large meals, the number of small meals increased, but total food intake and body weight decreased. While further work is needed, this is the first demonstration that meal size may be conditioned, using an aversion procedure, to remain under a target threshold and that this effect is distinct from taste avoidance. Corresponding reduction in food intake and body weight suggests that this phenomenon may have implications for developing weight loss strategies and understanding the efficacy of bariatric surgery. © 2016 The Obesity Society.

Behavioral architecture of opioid reward and aversion in C57BL/6 substrains

Directory of Open Access Journals (Sweden)

Stacey L Kirkpatrick

2015-01-01

Full Text Available Drug liking versus drug disliking is a subjective motivational measure in humans that assesses the addiction liability of drugs. Variation in this trait is hypothesized to influence vulnerability versus resilience toward substance abuse disorders and likely contains a genetic component. In rodents and humans, conditioned place preference (CPP / aversion (CPA is a Pavlovian conditioning paradigm whereby a learned preference for the drug-paired environment is used to infer drug liking whereas a learned avoidance or aversion is used to infer drug disliking. C57BL/6 inbred mouse substrains are nearly genetically identical, yet demonstrate robust differences in addiction-relevant behaviors, including locomotor sensitization to cocaine and consumption of ethanol. Here, we tested the hypothesis that B6 substrains would demonstrate differences in the rewarding properties of the mu opioid receptor agonist oxycodone (5 mg/kg, i.p. and the aversive properties of the opioid receptor antagonist naloxone (4 mg/kg, i.p.. Both substrains showed similar degrees of oxycodone-induced CPP; however, there was a three-fold enhancement of naloxone-induced CPA in agonist-naïve C57BL/6J relative to C57Bl/6NJ mice. Exploratory factor analysis of CPP and CPA identified unique factors that explain variance in behavioral expression of reward versus aversion. Conditioned Opioid-Like Behavior was a reward-based factor whereby drug-free locomotor variables resembling opioid treatment co-varied with the degree of CPP. Avoidance and Freezing was an aversion-based factor, whereby the increase in the number of freezing bouts co-varied with the degree of aversion. These results provide new insight into the behavioral architecture of the motivational properties of opioids. Future studies will use quantitative trait locus mapping in B6 substrains to identify novel genetic factors that contribute to the marked strain difference in NAL-CPA.

On the descriptive value of loss aversion in decisions under risk: Six clarifications

Directory of Open Access Journals (Sweden)

Eyal Ert

2013-05-01

Full Text Available Previous studies of loss aversion in decisions under risk have led to mixed results. Losses appear to loom larger than gains in some settings, but not in others. The current paper clarifies these results by highlighting six experimental manipulations that tend to increase the likelihood of the behavior predicted by loss aversion. These manipulations include: (1 framing of the safe alternative as the status quo; (2 ensuring that the choice pattern predicted by loss aversion maximizes the probability of positive (rather than zero or negative outcomes; (3 the use of high nominal (numerical payoffs; (4 the use of high stakes; (5 the inclusion of highly attractive risky prospects that creates a contrast effect; and (6 the use of long experiments in which no feedback is provided and in which the computation of the expected values is difficult. In addition, the results suggest the possibility of learning in the absence of feedback: The tendency to select simple strategies, like ``maximize the worst outcome'' which implies ``loss aversion'', increases when this behavior is not costly. Theoretical and practical implications are discussed.

Nicotine aversion: Neurobiological mechanisms and relevance to tobacco dependence vulnerability

Science.gov (United States)

Fowler, Christie D.; Kenny, Paul J.

2013-01-01

Nicotine stimulates brain reward circuitries, most prominently the mesocorticolimbic dopamine system, and this action is considered critical in establishing and maintaining the tobacco smoking habit. Compounds that attenuate nicotine reward are considered promising therapeutic candidates for tobacco dependence, but many of these agents have other actions that limit their potential utility. Nicotine is also highly noxious, particularly at higher doses, and aversive reactions to nicotine after initial exposure can decrease the likelihood of developing a tobacco habit in many first time smokers. Nevertheless, relatively little is known about the mechanisms of nicotine aversion. The purpose of this review is to present recent new insights into the neurobiological mechanisms that regulate avoidance of nicotine. First, the role of the mesocorticolimbic system, so often associated with nicotine reward, in regulating nicotine aversion is highlighted. Second, genetic variation that modifies noxious responses to nicotine and thereby influences vulnerability to tobacco dependence, in particular variation in the CHRNA5-CHRNA3-CHRNB4 nicotinic acetylcholine receptor (nAChR) subunit gene cluster, will be discussed. Third, the role of the habenular complex in nicotine aversion, primarily medial habenular projections to the interpeduncular nucleus (IPN) but also lateral habenular projections to rostromedial tegmental nucleus (RMTg) and ventral tegmental area (VTA) are reviewed. Forth, brain circuits that are enriched in nAChRs, but whose role in nicotine avoidance has not yet been assessed, will be proposed. Finally, the feasibility of developing novel therapeutic agents for tobacco dependence that act not by blocking nicotine reward but by enhancing nicotine avoidance will be considered. PMID:24055497

Investigating the Predictive Value of Functional MRI to Appetitive and Aversive Stimuli: A Pattern Classification Approach.

Directory of Open Access Journals (Sweden)

Ciara McCabe

Full Text Available Dysfunctional neural responses to appetitive and aversive stimuli have been investigated as possible biomarkers for psychiatric disorders. However it is not clear to what degree these are separate processes across the brain or in fact overlapping systems. To help clarify this issue we used Gaussian process classifier (GPC analysis to examine appetitive and aversive processing in the brain.25 healthy controls underwent functional MRI whilst seeing pictures and receiving tastes of pleasant and unpleasant food. We applied GPCs to discriminate between the appetitive and aversive sights and tastes using functional activity patterns.The diagnostic accuracy of the GPC for the accuracy to discriminate appetitive taste from neutral condition was 86.5% (specificity = 81%, sensitivity = 92%, p = 0.001. If a participant experienced neutral taste stimuli the probability of correct classification was 92. The accuracy to discriminate aversive from neutral taste stimuli was 82.5% (specificity = 73%, sensitivity = 92%, p = 0.001 and appetitive from aversive taste stimuli was 73% (specificity = 77%, sensitivity = 69%, p = 0.001. In the sight modality, the accuracy to discriminate appetitive from neutral condition was 88.5% (specificity = 85%, sensitivity = 92%, p = 0.001, to discriminate aversive from neutral sight stimuli was 92% (specificity = 92%, sensitivity = 92%, p = 0.001, and to discriminate aversive from appetitive sight stimuli was 63.5% (specificity = 73%, sensitivity = 54%, p = 0.009.Our results demonstrate the predictive value of neurofunctional data in discriminating emotional and neutral networks of activity in the healthy human brain. It would be of interest to use pattern recognition techniques and fMRI to examine network dysfunction in the processing of appetitive, aversive and neutral stimuli in psychiatric disorders. Especially where problems with reward and punishment processing have been implicated in the pathophysiology of the disorder.

How not to extend models of inequality aversion

Czech Academy of Sciences Publication Activity Database

Engelmann, Dirk

2012-01-01

Roč. 81, č. 2 (2012), s. 599-605 ISSN 0167-2681 Institutional research plan: CEZ:AV0Z70850503 Keywords : inequality aversion * efficiency * social preferences Subject RIV: AH - Economics Impact factor: 1.065, year: 2012

Heightened aversion to risk and loss in depressed patients with a suicide attempt history.

Science.gov (United States)

Baek, Kwangyeol; Kwon, JaeHyung; Chae, Jeong-Ho; Chung, Yong An; Kralik, Jerald D; Min, Jung-Ah; Huh, HyuJung; Choi, Kyung Mook; Jang, Kuk-In; Lee, Na-Bin; Kim, Sunyoung; Peterson, Bradley S; Jeong, Jaeseung

2017-09-11

Suicide attempters have been found to be impaired in decision-making; however, their specific biases in evaluating uncertain outcomes remain unclear. Here we tested the hypothesis that suicidal behavior is associated with heightened aversion to risk and loss, which might produce negative predictions about uncertain future events. Forty-five depressed patients with a suicide attempt history, 47 nonsuicidal depressed patients, and 75 healthy controls participated in monetary decision-making tasks assessing risk and loss aversion. Suicide attempters compared with the other groups exhibited greater aversion to both risk and loss during gambles involving potential loss. Risk and loss aversion correlated with each other in the depressed patients, suggesting that a common pathophysiological mechanism underlies these biases. In addition, emotion regulation via suppression, a detrimental emotional control strategy, was positively correlated with loss aversion in the depressed patients, also implicating impairment in regulatory processes. A preliminary fMRI study also found disrupted neural responses to potential gains and losses in the subgenual anterior cingulate cortex, insula cortex, and left amygdala, brain regions involved in valuation, emotion reactivity, and emotion regulation. The findings thus implicate heightened negative valuation in decision-making under risk, and impaired emotion regulation in depressed patients with a history of suicide attempts.

Effects of antiemetics on the acquisition and recall of radiation- and lithium chloride-induced conditioned taste aversions

International Nuclear Information System (INIS)

Rabin, B.M.; Hunt, W.A.

1983-01-01

A series of experiments were run to evaluate the effect of antiemetics on the acquisition and recall of a conditioned taste aversion induced by exposure to ionizing radiation or by injection of lithium chloride. Groups of male rats were exposed to 100 rad gamma radiation or 3 mEq/kg lithium chloride following consumption of a 10% sucrose solution. They were then injected with saline or with one of three antiemetics (prochlorperazine, trimethobenzamide, or cyclizine) at dose levels that have been reported to be effective in attenuating a previously acquired lithium chloride-induced taste aversion. The pretreatments with antiemetics had no effect on the acquisition or recall of either the lithium chloride- or radiation-induced taste aversion. The data suggest that antiemetics do not disrupt lithium chloride-induced taste aversions as previously reported, nor do they effect radiation-induced taste aversion learning

Low- and high-testosterone individuals exhibit decreased aversion to economic risk.

Science.gov (United States)

Stanton, Steven J; Mullette-Gillman, O'Dhaniel A; McLaurin, R Edward; Kuhn, Cynthia M; LaBar, Kevin S; Platt, Michael L; Huettel, Scott A

2011-04-01

Testosterone is positively associated with risk-taking behavior in social domains (e.g., crime, physical aggression). However, the scant research linking testosterone to economic risk preferences presents inconsistent findings. We examined the relationship between endogenous testosterone and individuals' economic preferences (i.e., risk preference, ambiguity preference, and loss aversion) in a large sample (N = 298) of men and women. We found that endogenous testosterone levels have a significant U-shaped association with individuals' risk and ambiguity preferences, but not loss aversion. Specifically, individuals with low or high levels of testosterone (more than 1.5 SD from the mean for their gender) were risk and ambiguity neutral, whereas individuals with intermediate levels of testosterone were risk and ambiguity averse. This relationship was highly similar in men and women. In contrast to received wisdom regarding testosterone and risk, the present data provide the first robust evidence for a nonlinear association between economic preferences and levels of endogenous testosterone.

Long-term aversive taste memory requires insular and amygdala protein degradation.

Science.gov (United States)

Rodriguez-Ortiz, Carlos J; Balderas, Israela; Saucedo-Alquicira, Fernando; Cruz-Castañeda, Paulina; Bermudez-Rattoni, Federico

2011-03-01

Some reports have shown that the ubiquitin-proteasome system (UPS) is necessary to degrade repressor factors to produce new proteins essential to memory consolidation. Furthermore, recent evidence suggests that memory updating also relies on protein degradation through the UPS. To evaluate whether degradation of proteins is part of the cellular events needed for long-term storage of taste aversion, we injected lactacystin--an UPS inhibitor--into the amygdala and/or insular cortex 30 min before the first or second training trials. The results revealed that degradation of proteins in either the amygdala or insular cortex suffices for long-term stabilization of first-time encounter taste aversion. On the other hand, lactacystin applied in the insula, but not in the amygdala, before the second training prevented long-term storage of updated information. Our results support that degradation of proteins by means of the UPS is required every time taste aversion is to be stored in long-term memory. Copyright © 2010 Elsevier Inc. All rights reserved.

Public Sector Employees: Risk Averse and Altruistic?

NARCIS (Netherlands)

M.W.J.M. Buurman (Margaretha); A.J. Dur (Robert); S. Bossche, van den (Seth)

2009-01-01

textabstractWe assess whether public sector employees have a stronger inclination to serve others and are more risk averse than employees in the private sector. A unique feature of our study is that we use revealed rather than stated preferences data. Respondents of a large-scale survey were offered

Public sector employees: risk averse and altruistic?

NARCIS (Netherlands)

Buurman, M.; Delfgaauw, J.; Dur, R.; Bossche, S.N.J. van den

2012-01-01

We assess whether public sector employees have a stronger inclination to serve others and are more risk averse than employees in the private sector. A unique feature of our study is that we use revealed rather than stated preferences data. Respondents of a large-scale survey were offered a

Public sector employees: risk averse and altruistic?

NARCIS (Netherlands)

Buurman, M.; Dur, R.; Bossche, S.N.J. van den

2009-01-01

We assess whether public sector employees have a stronger inclination to serve others and are more risk averse than employees in the private sector. A unique feature of our study is that we use revealed rather than stated preferences data. Respondents of a large-scale survey were offered a

Long-term changes in amphetamine-induced reinforcement and aversion in rats following exposure to 56Fe particle

Science.gov (United States)

Rabin, B. M.; Joseph, J. A.; Shukitt-Hale, B.

Exposing rats to heavy particles produces alterations in the functioning of dopaminergic neurons and in the behaviors that depend upon the integrity of the dopaminergic system. Two of these dopamine-dependent behaviors include amphetamine-induced reinforcement, measure using the conditioned place preference procedure, and amphetamine-induced reinforcement, measured using the conditioned place preference procedure, and amphetamine-induced aversion, measured using the conditioned taste aversion. Previous research has shown that exposing rats to 1.0 Gy of 1GeV/n 56Fe particles produced a disruption of an amphetamine-induced taste aversion 3 days following exposure, but produced an apparent enhancement of the aversion 112 days following exposure. The present experiments were designed to provide a further evaluation of these results by examining taste aversion learning 154 days following exposure to 1.0Gy 56Fe particles and to establish the convergent validity of the taste aversion results by looking at the effects of exposure on the establishment of an amphetamine-induced conditioned place preference 3, 7, and 16 weeks following irradiation. The taste aversion results failed to confirm the apparent enhancement of the amphetamine-induced CTA observed in the prior experiment. However, exposure to 56Fe particles prevented the acquisition of amphetamine-induced place preference at all three-time intervals. The results are interpreted as indicating that exposure to heavy particles can produce long-term changes in behavioral functioning.

PERFORMANCE EVALUATION AND RISK AVERSION RATE FOR SEVERAL STOCK INDICES IN INDONESIA STOCK EXCHANGE

Directory of Open Access Journals (Sweden)

Robiyanto Robiyanto

2017-03-01

Full Text Available There are numerous stock indices in Indonesia Stock Exchange. Several of them are LQ-45, MBX, DBX, JII, SRI-KEHATI, PEFINDO-25, BISNIS-27, IDX-30 and KOMPAS-100. Unfortunately there are limi­ted researches which have been done to measure those indices performance specifically. The same condition also occurs on risk aversion level usage in Indonesia Stock Exchange, only few numbers of researches use this me­a­surement in the portfolio valuation. Based on that, this research measured the performance and risk aversion rate of those indices in Indonesia Stock Exchange. The results of this study were SRI-KEHATI becomes the best performer with the highest risk aversion rate, while Jakarta Islamic Index (JII produces the lowest positive per­formance with the lowest risk aversion rate. This finding shows that sharia stocks’ characters (i.e. usury free could give relieveness and convenience regardless its per­formance.

Cross-sectional survey: risk-averse French general practitioners are more favorable toward influenza vaccination.

Science.gov (United States)

Massin, Sophie; Ventelou, Bruno; Nebout, Antoine; Verger, Pierre; Pulcini, Céline

2015-01-29

We tested the following hypotheses: (i) risk-averse general practitioners (GPs) are more likely to be vaccinated against influenza; (ii) and risk-averse GPs recommend influenza vaccination more often to their patients. In risk-averse GPs, the perceived benefits of the vaccine and/or the perceived risks of the infectious disease might indeed outweigh the perceived risks of the vaccine. In 2010-2012, we conducted a cross-sectional survey of a nationwide French representative sample of 1136 GPs. Multivariate analyses adjusted for four stratification variables (age, gender, urban/suburban/rural practice location and annual patient consultations) and for GPs' characteristics (group/solo practice, and occasional practice of alternative medicine, e.g., homeopathy) looked for associations between their risk attitudes and self-reported vaccination behavior. Individual risk attitudes were expressed as a continuous variable, from 0 (risk-tolerant) to 10 (risk-averse). Overall, 69% of GPs reported that they were very favorable toward vaccination in general. Self-reported vaccination coverage was 78% for 2009/2010 seasonal influenza and 62% for A/H1N1 pandemic influenza. Most GPs (72%) reported recommending the pandemic influenza vaccination to at-risk young adults in 2009, but few than half (42%) to young adults not at risk. In multivariate analyses, risk-averse GPs were more often vaccinated against seasonal (marginal effect=1.3%, P=0.02) and pandemic influenza (marginal effect=1.5%, P=0.02). Risk-averse GPs recommended the pandemic influenza vaccination more often than their more risk-tolerant colleagues to patients without risk factors (marginal effect=1.7%, P=0.01), but not to their at-risk patients and were more favorable toward vaccination in general (marginal effect=1.5%, P=0.04). Individual risk attitudes may influence GPs' practices regarding influenza vaccination, both for themselves and their patients. Our results suggest that risk-averse GPs may perceive the risks

Aversive learning of odor-heat associations in ants.

Science.gov (United States)

Desmedt, Lucie; Baracchi, David; Devaud, Jean-Marc; Giurfa, Martin; d'Ettorre, Patrizia

2017-12-15

Ants have recently emerged as useful models for the study of olfactory learning. In this framework, the development of a protocol for the appetitive conditioning of the maxilla-labium extension response (MaLER) provided the possibility of studying Pavlovian odor-food learning in a controlled environment. Here we extend these studies by introducing the first Pavlovian aversive learning protocol for harnessed ants in the laboratory. We worked with carpenter ants Camponotus aethiops and first determined the capacity of different temperatures applied to the body surface to elicit the typical aversive mandible opening response (MOR). We determined that 75°C is the optimal temperature to induce MOR and chose the hind legs as the stimulated body region because of their high sensitivity. We then studied the ability of ants to learn and remember odor-heat associations using 75°C as the unconditioned stimulus. We studied learning and short-term retention after absolute (one odor paired with heat) and differential conditioning (a punished odor versus an unpunished odor). Our results show that ants successfully learn the odor-heat association under a differential-conditioning regime and thus exhibit a conditioned MOR to the punished odor. Yet, their performance under an absolute-conditioning regime is poor. These results demonstrate that ants are capable of aversive learning and confirm previous findings about the different attentional resources solicited by differential and absolute conditioning in general. © 2017. Published by The Company of Biologists Ltd.

Event-related potential components as measures of aversive conditioning in humans.

Science.gov (United States)

Bacigalupo, Felix; Luck, Steven J

2018-04-01

For more than 60 years, the gold standard for assessing aversive conditioning in humans has been the skin conductance response (SCR), which arises from the activation of the peripheral nervous system. Although the SCR has been proven useful, it has some properties that impact the kinds of questions it can be used to answer. In particular, the SCR is slow, reaching a peak 4-5 s after stimulus onset, and it decreases in amplitude after a few trials (habituation). The present study asked whether the late positive potential (LPP) of the ERP waveform could be a useful complementary method for assessing aversive conditioning in humans. The SCR and LPP were measured in an aversive conditioning paradigm consisting of three blocks in which one color was paired with a loud noise (CS+) and other colors were not paired with the noise (CS-). Participants also reported the perceived likelihood of being exposed to the noise for each color. Both SCR and LPP were significantly larger on CS+ trials than on CS- trials. However, SCR decreased steeply after the first conditioning block, whereas LPP and self-reports were stable over blocks. These results indicate that the LPP can be used to assess aversive conditioning and has several useful properties: (a) it is a direct response of the central nervous system, (b) it is fast, with an onset latency of 300 ms, (c) it does not habituate over time. © 2017 Society for Psychophysiological Research.

Effects of Swim Stress on Neophobia and Reconditioning Using a Conditioned Taste Aversion Procedure

Science.gov (United States)

Walker, Jennifer M.; Ramsey, Ashley K.; Fowler, Stephanie W.; Schachtman, Todd R.

2012-01-01

Previous research has found that swim stress during a classical conditioning trial attenuates conditioned taste aversion (CTA). In the current study, rats were used to examine the effects of inescapable swim stress on the habituation of neophobia to a flavored solution and reacquisition of an extinguished conditioned taste aversion. In Experiment…

Extinction of Aversive Classically Conditioned Human Sexual Response

NARCIS (Netherlands)

Brom, M.; Laan, E.; Everaerd, W.; Spinhoven, P.; Both, S.

INTRODUCTION: Research has shown that acquired subjective likes and dislikes are quite resistant to extinction. Moreover, studies on female sexual response demonstrated that diminished genital arousal and positive affect toward erotic stimuli due to aversive classical conditioning did not extinguish

Extinction of aversive classically conditioned human sexual response

NARCIS (Netherlands)

Brom, Mirte; Laan, Ellen; Everaerd, Walter; Spinhoven, Philip; Both, Stephanie

2015-01-01

Research has shown that acquired subjective likes and dislikes are quite resistant to extinction. Moreover, studies on female sexual response demonstrated that diminished genital arousal and positive affect toward erotic stimuli due to aversive classical conditioning did not extinguish during an

My loss is your loss ... Sometimes: loss aversion and the effect of motivational biases.

Science.gov (United States)

Wilson, Robyn S; Arvai, Joseph L; Arkes, Hal R

2008-08-01

Findings from previous studies of individual decision-making behavior predict that losses will loom larger than gains. It is less clear, however, if this loss aversion applies to the way in which individuals attribute value to the gains and losses of others, or if it is robust across a broad spectrum of policy and management decision contexts. Consistent with previous work, the results from a series of experiments reported here revealed that subjects exhibited loss aversion when evaluating their own financial gains and losses. The presence of loss aversion was also confirmed for the way in which individuals attribute value to the financial gains and losses of others. However, similar evaluations within social and environmental contexts did not exhibit loss aversion. In addition, research subjects expected that individuals who were unknown to them would significantly undervalue the subjects' own losses across all contexts. The implications of these findings for risk-based policy and management are many. Specifically, they warrant caution when relying upon loss aversion to explain or predict the reaction of affected individuals to risk-based decisions that involve moral or protected values. The findings also suggest that motivational biases may lead decisionmakers to assume that their attitudes and beliefs are common among those affected by a decision, while those affected may expect unfamiliar others to be unable to identify and act in accordance with shared values.

Molecular signals into the insular cortex and amygdala during aversive gustatory memory formation.

Science.gov (United States)

Bermúdez-Rattoni, Federico; Ramírez-Lugo, Leticia; Gutiérrez, Ranier; Miranda, María Isabel

2004-02-01

In this paper, we will provide evidence of the putative molecular signals and biochemical events that mediate the formation of long-lasting gustatory memory trace. When an animal drinks a novel taste (the conditioned stimulus; CS) and it is later associated with malaise (unconditioned stimulus; US), the animal will reject it in the next presentation, developing a long-lasting taste aversion, i.e., the taste cue becomes an aversive signal, and this is referred to as conditioning taste aversion. Different evidence indicates that the novel stimulus (taste) induces a rapid and strong cortical acetylcholine activity that decreases when the stimulus becomes familiar after several presentations. Cholinergic activation via muscarinic receptors initiates a series of intracellular events leading to plastic changes that could be related to short- and/or long-term memory gustatory trace. Such plastic changes facilitate the incoming US signals carried out by, in part, the glutamate release induced by the US. Altogether, these events could produce the cellular changes related to the switch from safe to aversive taste memory trace. A proposed working model to explain the biochemical sequence of signals during taste memory formation will be discussed.

Exploring disadvantageous inequality aversion in children: How cost and discrepancy influence decision-making

Directory of Open Access Journals (Sweden)

Amanda eWilliams

2014-09-01

Full Text Available This research examined disadvantageous inequality aversion in 4- and 6-year-old children. Using the resource allocation paradigm, we explored how inequality aversion was influenced by whether a cost was associated with the equitable choice. We also investigated whether preferences for equality differed depending on whether the inequitable choice presented a small or large discrepancy between the payoff of the participant and their partner. The results demonstrated that cost plays a large role in decision-making, as children preferred equality more when there was no cost associated with it compared to when there was a cost. Interestingly, the effect of cost also affected discrepancy, with children more likely to choose equality when the discrepancy was large as opposed to small, in cost trials but not in no cost trials. Finally, the effect of discrepancy also interacted with age, with older children being more sensitive to the discrepancy between themselves and their partner Together, these results suggest that children’s behaviour is not indiscriminately guided by a generalized aversion to inequality or established fairness norms. Alternate motives for inequality aversion are discussed.

Effects of phenobarbital on taste aversion induced by x-radiation

International Nuclear Information System (INIS)

Jolicoeur, F.B.; Wayner, M.J.; Rondeau, D.B.; Merkel, A.D.; Bassano, D.A.

1979-01-01

The effects of phenobarbital on taste aversion induced by x-radiation were examined. Rats were adapted to a 23 hr 50 min water deprivation schedule. On the Treatment Day animals were given a novel 0.125% Na saccharin solution during the 10 min drinking session and were then exposed to 100 rads of x-radiation. The saccharin solution was presented again on six subsequent Test Days. Phenobarbital in doses of 20, 40, 60 and 80 mg/kg was adminstered 15 min prior to drinking on the first Test Day. Results demonstrate the phenobarbital in all doses tested has a significant attenuating effect on radiation induced taste aversion

The Use of Aversives in Special Education: Legal and Practice Considerations for School Principals

Science.gov (United States)

Katsiyannis, Antonis; Losinski, Mickey; Whitford, Denise K.; Counts, Jennifer

2017-01-01

The use of aversives as a method for behavioral intervention in U.S. public schools has been a persistent concern and often subject to litigation, particularly among students with disabilities. The use of aversives (restraint, seclusion, and corporal punishment) have been supported in some cases due to their perceived necessity to keep children…

Aversive effects of ethanol in adolescent versus adult rats: potential causes and implication for future drinking.

Science.gov (United States)

Schramm-Sapyta, Nicole L; DiFeliceantonio, Alexandra G; Foscue, Ethan; Glowacz, Susan; Haseeb, Naadeyah; Wang, Nancy; Zhou, Cathy; Kuhn, Cynthia M

2010-12-01

Many people experiment with alcohol and other drugs of abuse during their teenage years. Epidemiological evidence suggests that younger initiates into drug taking are more likely to develop problematic drug seeking behavior, including binge and other high-intake behaviors. The level of drug intake for any individual depends on the balance of rewarding and aversive effects of the drug in that individual. Multiple rodent studies have demonstrated that aversive effects of drugs of abuse are reduced in adolescent compared to adult animals. In this study, we addressed 2 key questions: First, do reduced aversive effects of ethanol in younger rats correlate with increased ethanol consumption? Second, are the reduced aversive effects in adolescents attributable to reduced sensitivity to ethanol's physiologic effects? Adolescent and adult rats were tested for ethanol conditioned taste aversion (CTA) followed by a voluntary drinking period, including postdeprivation consumption. Multivariate regression was used to assess correlations. In separate experiments, adolescent and adult rats were tested for their sensitivity to the hypothermic and sedative effects of ethanol, and for blood ethanol concentrations (BECs). We observed that in adolescent rats but not adults, taste aversion was inversely correlated with postdeprivation consumption. Adolescents also exhibited a greater increase in consumption after deprivation than adults. Furthermore, the age difference in ethanol CTA was not attributable to differences in hypothermia, sedation, or BECs. These results suggest that during adolescence, individuals that are insensitive to aversive effects are most likely to develop problem drinking behaviors. These results underscore the importance of the interaction between developmental stage and individual variation in sensitivity to alcohol. Copyright © 2010 by the Research Society on Alcoholism.

Genotypic Influence on Aversive Conditioning in Honeybees, Using a Novel Thermal Reinforcement Procedure

Science.gov (United States)

Junca, Pierre; Carcaud, Julie; Moulin, Sibyle; Garnery, Lionel; Sandoz, Jean-Christophe

2014-01-01

In Pavlovian conditioning, animals learn to associate initially neutral stimuli with positive or negative outcomes, leading to appetitive and aversive learning respectively. The honeybee (Apis mellifera) is a prominent invertebrate model for studying both versions of olfactory learning and for unraveling the influence of genotype. As a queen bee mates with about 15 males, her worker offspring belong to as many, genetically-different patrilines. While the genetic dependency of appetitive learning is well established in bees, it is not the case for aversive learning, as a robust protocol was only developed recently. In the original conditioning of the sting extension response (SER), bees learn to associate an odor (conditioned stimulus - CS) with an electric shock (unconditioned stimulus - US). This US is however not a natural stimulus for bees, which may represent a potential caveat for dissecting the genetics underlying aversive learning. We thus first tested heat as a potential new US for SER conditioning. We show that thermal stimulation of several sensory structures on the bee’s body triggers the SER, in a temperature-dependent manner. Moreover, heat applied to the antennae, mouthparts or legs is an efficient US for SER conditioning. Then, using microsatellite analysis, we analyzed heat sensitivity and aversive learning performances in ten worker patrilines issued from a naturally inseminated queen. We demonstrate a strong influence of genotype on aversive learning, possibly indicating the existence of a genetic determinism of this capacity. Such determinism could be instrumental for efficient task partitioning within the hive. PMID:24828422

Rationality on the rise: Why relative risk aversion increases with stake size

OpenAIRE

Fehr-Duda, Helga; Bruhin, Adrian; Epper, Thomas F.; Schubert, Renate

2008-01-01

How does risk tolerance vary with stake size? This important question cannot be adequately answered if framing effects, nonlinear probability weighting, and heterogeneity of preference types are neglected. We show that, contrary to gains, no coherent change in relative risk aversion is observed for losses. The increase in relative risk aversion over gains cannot be captured by the curvature of the utility function. It is driven predominantly by a change in probability weighting of a majority ...

Optimal combined purchasing strategies for a risk-averse manufacturer under price uncertainty

Directory of Open Access Journals (Sweden)

Qiao Wu

2015-09-01

Full Text Available Purpose: The purpose of our paper is to analyze optimal purchasing strategies when a manufacturer can buy raw materials from a long-term contract supplier and a spot market under spot price uncertainty. Design/methodology/approach: This procurement model can be solved by using dynamic programming. First, we maximize the DM’s utility of the second period, obtaining the optimal contract quantity and spot quantity for the second period. Then, maximize the DM’s utility of both periods, obtaining the optimal purchasing strategy for the first period. We use a numerical method to compare the performance level of a pure spot sourcing strategy with that of a mixed strategy. Findings: Our results show that optimal purchasing strategies vary with the trend of contract prices. If the contract price falls, the total quantity purchased in period 1 will decrease in the degree of risk aversion. If the contract price increases, the total quantity purchased in period 1 will increase in the degree of risk aversion. The relationship between the optimal contract quantity and the degree of risk aversion depends on whether the expected spot price or the contract price is larger in period 2. Finally, we compare the performance levels between a combined strategy and a spot sourcing strategy. It shows that a combined strategy is optimal for a risk-averse buyer. Originality/value: It’s challenging to deal with a two-period procurement problem with risk consideration. We have obtained results of a two-period procurement problem with two sourcing options, namely contract procurement and spot purchases. Our model incorporates the buyer’s risk aversion factor and the change of contract prices, which are not addressed in early studies.

Subjective expected utility with non-increasing risk aversion

NARCIS (Netherlands)

Wakker, P.P.

1989-01-01

It is shown that assumptions about risk aversion, usually studied under the presupposition of expected utility maximization, have a surprising extra merit at an earlier stage of the measurement work: together with the sure-thing principle, these assumptions imply subjective expected utility

The effect of post-conditioning exposure to morphine on the retention of a morphine-induced conditioned taste aversion.

Science.gov (United States)

Jacobs, W J; Zellner, D A; LoLordo, V M; Riley, A L

1981-06-01

In the following experiment, multiple injections of morphine sulfate following the acquisition of a morphine-induced taste aversion had no effect on the retention of the previously acquired aversion. Post-conditioning injections of morphine resulted in the development of physical dependence to morphine and led to a decrement in the ability of morphine to induce a subsequent aversion to a second novel taste. This failure of post-conditioning exposures to morphine to affect a previously acquired morphine-induced taste aversion even though tolerance to morphine had occurred was discussed in the context of Rescorla's event-memory model of conditioning.

Reward-centricity and attenuated aversions: An adolescent phenotype emerging from studies in laboratory animals.

Science.gov (United States)

Doremus-Fitzwater, Tamara L; Spear, Linda P

2016-11-01

Adolescence is an evolutionarily conserved developmental period, with neural circuits and behaviors contributing to the detection, procurement, and receipt of rewards bearing similarity across species. Studies with laboratory animals suggest that adolescence is typified by a "reward-centric" phenotype-an increased sensitivity to rewards relative to adults. In contrast, adolescent rodents are reportedly less sensitive to the aversive properties of many drugs and naturally aversive stimuli. Alterations within the mesocorticolimbic dopamine and endocannabinoid systems likely contribute to an adolescent reward-sensitive, yet aversion-resistant, phenotype. Although early hypotheses postulated that developmental changes in dopaminergic circuitry would result in a "reward deficiency" syndrome, evidence now suggests the opposite: that adolescents are uniquely poised to seek out hedonic stimuli, experience greater "pleasure" from rewards, and consume rewarding stimuli in excess. Future studies that more clearly define the role of specific brain regions and neurotransmitter systems in the expression of behaviors toward reward- and aversive-related cues and stimuli are necessary to more fully understand an adolescent-proclivity for and vulnerability to rewards and drugs of potential abuse. Copyright © 2016 Elsevier Ltd. All rights reserved.

Developmental differences in aversive conditioning, extinction, and reinstatement: A study with children, adolescents, and adults.

Science.gov (United States)

Waters, Allison M; Theresiana, Cindy; Neumann, David L; Craske, Michelle G

2017-07-01

This study investigated developmental differences in aversive conditioning, extinction, and reinstatement (i.e., the recovery of conditioned aversive associations following reexposure to the unconditioned stimulus [US] post-extinction). This study examined these mechanisms in children (M age =8.8years), adolescents (M age =16.1years), and adults (M age =32.3years) using differential aversive conditioning with a geometric shape conditional stimulus (CS+) paired with an aversive sound US and another shape (CS-) presented alone. Following an extinction phase in which both CSs were presented alone, half of the participants in each age group received three US exposures (reinstatement condition) and the other half did not (control condition), followed by all participants completing an extinction retest phase on the same day. Findings indicated (a) significant differences in generalizing aversive expectancies to safe stimuli during conditioning and extinction that persisted during retest in children relative to adults and adolescents, (b) significantly less positive CS reevaluations during extinction that persisted during retest in adolescents relative to adults and children, and (c) reinstatement of US expectancies to the CS+ relative to the CS- in all age groups. Results suggest important differences in stimulus safety learning in children and stimulus valence reevaluation in adolescents relative to adults. Copyright © 2017 Elsevier Inc. All rights reserved.

Dexamethasone: a potent blocker for radiation-induced taste aversion in rats

International Nuclear Information System (INIS)

Cairnie, A.B.; Leach, K.E.

1982-01-01

Rats, trained to drink water during a single 30-min period each day, were then given 0.1% saccharin twice a week and water on other days for 30 min. If 20 rad of radiation (0.2 Gy) were given each time 30 to 40 min after the saccharin the rats developed a profound aversion to saccharin during the course of three weeks, whereas control groups failed to do so. This paradigm was then used to test the ability of drugs, given twice weekly immediately after the saccharin, to prevent the development during three weeks of an aversion when 20 rad was given, 30 to 40 min later. Insulin, domperidone, haloperidol, acetylsalicylic acid, naloxone, chlorpheniramine, cimetidine, and dimethyl sulphoxide were tested without notable success. However dexamethasone, at doses ranging from 0.013 mg/kg to 1.3 mg/kg, significantly attenuated the conditioned taste aversion by up to 60 percent. The results are discussed in terms of a search for an antinauseant and antiemetic drug effective against radiation in man

Static vs Dynamic Auctions with Ambiguity Averse Bidders

NARCIS (Netherlands)

Carvalho, M.

2012-01-01

Abstract: This paper presents the outcome of a dynamic price-descending auction when the distribution of the private values is uncertain and bidders exhibit ambiguity aversion. In contrast to sealed-bid auctions, in open auctions the bidders get information about the other bidders' private values

Joint measurement of risk aversion, prudence, and temperance

NARCIS (Netherlands)

Ebert, S.; Wiesen, D.

Risk aversion—but also the higher-order risk preferences of prudence and temperance—are fundamental concepts in the study of economic decision making. We propose a method to jointly measure the intensity of risk aversion, prudence, and temperance. Our theoretical approach is to define risk

Myopic Loss Aversion : Information Feedback vs. Investment Flexibility

NARCIS (Netherlands)

Bellemare, C.; Krause, M.; Kroger, S.; Zhang, C.

2004-01-01

We experimentally disentangle the effect of information feedback from the effect of investment flexibility on the investment behavior of a myopically loss averse investor.Our findings show that varying the information condition alone suffices to induce behavior that is in line with the hypothesis of

Aversive Techniques and the Doctrine of Least Restrictive Alternative.

Science.gov (United States)

Barton, Lyle E.; And Others

1983-01-01

Litigation and the issues surrounding the use of behavioral procedures to handicapped persons are reviewed. Attention is directed to the use of aversive techniques, e.g., corporal punishment, electric shock, timeout, and restraint. (SEW)

Differentiating aversive conditioning in bistable perception: Avoidance of a percept vs. salience of a stimulus.

Science.gov (United States)

Wilbertz, Gregor; Sterzer, Philipp

2018-05-01

Alternating conscious visual perception of bistable stimuli is influenced by several factors. In order to understand the effect of negative valence, we tested the effect of two types of aversive conditioning on dominance durations in binocular rivalry. Participants received either aversive classical conditioning of the stimuli shown alone between rivalry blocks, or aversive percept conditioning of one of the two possible perceptual choices during rivalry. Both groups showed successful aversive conditioning according to skin conductance responses and affective valence ratings. However, while classical conditioning led to an immediate but short-lived increase in dominance durations of the conditioned stimulus, percept conditioning yielded no significant immediate effect but tended to decrease durations of the conditioned percept during extinction. These results show dissociable effects of value learning on perceptual inference in situations of perceptual conflict, depending on whether learning relates to the decision between conflicting perceptual choices or the sensory stimuli per se. Copyright © 2018 Elsevier Inc. All rights reserved.

Lateral Habenula determines long-term storage of aversive memories.

Directory of Open Access Journals (Sweden)

Micol eTomaiuolo

2014-05-01

Full Text Available The Lateral Habenula (LHb is a small brain structure that codifies negative motivational value and has been related to major depression. It has been shown recently that LHb activation is sufficient to induce aversive associative learning; however the key question about whether LHb activation is required for an aversive memory to be formed has not been addressed. In this article we studied the function of the LHb in memory formation using the Inhibitory Avoidance task (IA. We found that LHb inactivation during IA training does not disrupt memory when assessed 24 hours after, but abolishes it 7 days later, indicating that LHb activity during memory acquisition is not necessary for memory formation, but regulates its temporal stability. These effects suggest that LHb inactivation modifies subjective perception of the training experience.

Eliciting and Measuring Betrayal Aversion using the BDM Mechanism*

Science.gov (United States)

Quercia, Simone

2016-01-01

Betrayal aversion has been operationalized as the evidence that subjects demand a higher risk premium to take social risks compared to natural risks. This evidence has been first shown by Bohnet and Zeckhauser (2004) using an adaptation of the Becker – DeGroot – Marschak mechanism (BDM, Becker et al. (1964)). We compare their implementation of the BDM mechanism with a new version designed to facilitate subjects’ comprehension. We find that, although the two versions produce different distributions of values, the size of betrayal aversion, measured as an average treatment difference between social and natural risk settings, is not different across the two versions. We further show that our implementation is preferable to use in practice as it reduces substantially subjects’ mistakes and the likelihood of noisy valuations. PMID:27366658

Left-right functional asymmetry of ventral hippocampus depends on aversiveness of situations.

Science.gov (United States)

Sakaguchi, Yukitoshi; Sakurai, Yoshio

2017-05-15

Many studies suggest that animals exhibit lateralized behaviors during aversive situations, and almost all animals exhibit right hemisphere-dominant behaviors associated with fear or anxiety. However, which brain structure in each hemisphere underlies such lateralized function is unclear. In this study, we focused on the hippocampus and investigated the effects of bilateral and unilateral lesions of the ventral hippocampus (VH) on anxiety-like behavior using the successive alleys test. We also examined the expression of c-fos in the VH, which was induced by an aversive situation. Results revealed that consistent right VH dominance trended with the anxiety level. Weaker anxiety induced both right and left VH functions, whereas stronger anxiety induced right VH function. From these results, we conclude that animals are able to adaptively regulate their behaviors to avoid aversive stimuli by changing the functional dominance of their left and right VH. Copyright © 2017 Elsevier B.V. All rights reserved.

Female babies and risk-aversion: Causal evidence from hospital wards.

Science.gov (United States)

Pogrebna, Ganna; Oswald, Andrew J; Haig, David

2018-03-01

Using ultrasound scan data from paediatric hospitals, and the exogenous 'shock' of learning the gender of an unborn baby, the paper documents the first causal evidence that offspring gender affects adult risk-aversion. On a standard Holt-Laury criterion, parents of daughters, whether unborn or recently born, become almost twice as risk-averse as parents of sons. The study demonstrates this in longitudinal and cross-sectional data, for fathers and mothers, for babies in the womb and new-born children, and in a West European nation and East European nation. These findings may eventually aid our understanding of risky health behaviors and gender inequalities. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

A conditioned aversion study of sucrose and SC45647 taste in TRPM5 knockout mice.

Science.gov (United States)

Eddy, Meghan C; Eschle, Benjamin K; Peterson, Darlene; Lauras, Nathan; Margolskee, Robert F; Delay, Eugene R

2012-06-01

Previously, published studies have reported mixed results regarding the role of the TRPM5 cation channel in signaling sweet taste by taste sensory cells. Some studies have reported a complete loss of sweet taste preference in TRPM5 knockout (KO) mice, whereas others have reported only a partial loss of sweet taste preference. This study reports the results of conditioned aversion studies designed to motivate wild-type (WT) and KO mice to respond to sweet substances. In conditioned taste aversion experiments, WT mice showed nearly complete LiCl-induced response suppression to sucrose and SC45647. In contrast, TRPM5 KO mice showed a much smaller conditioned aversion to either sweet substance, suggesting a compromised, but not absent, ability to detect sweet taste. A subsequent conditioned flavor aversion experiment was conducted to determine if TRPM5 KO mice were impaired in their ability to learn a conditioned aversion. In this experiment, KO and WT mice were conditioned to a mixture of SC45647 and amyl acetate (an odor cue). Although WT mice avoided both components of the stimulus mixture, they avoided SC45647 more than the odor cue. The KO mice also avoided both stimuli, but they avoided the odor component more than SC45647, suggesting that while the KO mice are capable of learning an aversion, to them the odor cue was more salient than the taste cue. Collectively, these findings suggest the TRPM5 KO mice have some residual ability to detect SC45647 and sucrose, and, like bitter, there may be a TRPM5-independent transduction pathway for detecting these substances.

Risk aversion and religious behaviour

DEFF Research Database (Denmark)

Nielsen, Jytte Seested; Bech, Mickael; Christensen, Kaare

2017-01-01

would expect that risk averse individuals would demand a more generous protection plan which they may do by devoting more effort and resources into religious activities such as church attendance and prayer, which seems to be in accordance with previous empirical results. However, a general concern...... and prayer frequency on the other controlling for unobservable variables using survey data of Danish same-sex twin pairs. We verify the correlation between risk preferences and religion found previously by carrying out cross-sectional analyses. We also show that the association between risk attitudes...

Pupillometry reveals the physiological underpinnings of the aversion to holes.

Science.gov (United States)

Ayzenberg, Vladislav; Hickey, Meghan R; Lourenco, Stella F

2018-01-01

An unusual, but common, aversion to images with clusters of holes is known as trypophobia. Recent research suggests that trypophobic reactions are caused by visual spectral properties also present in aversive images of evolutionary threatening animals (e.g., snakes and spiders). However, despite similar spectral properties, it remains unknown whether there is a shared emotional response to holes and threatening animals. Whereas snakes and spiders are known to elicit a fear reaction, associated with the sympathetic nervous system, anecdotal reports from self-described trypophobes suggest reactions more consistent with disgust, which is associated with activation of the parasympathetic nervous system. Here we used pupillometry in a novel attempt to uncover the distinct emotional response associated with a trypophobic response to holes. Across two experiments, images of holes elicited greater constriction compared to images of threatening animals and neutral images. Moreover, this effect held when controlling for level of arousal and accounting for the pupil grating response. This pattern of pupillary response is consistent with involvement of the parasympathetic nervous system and suggests a disgust, not a fear, response to images of holes. Although general aversion may be rooted in shared visual-spectral properties, we propose that the specific emotion is determined by cognitive appraisal of the distinct image content.

Risk aversion affects economic values of blue fox breeding scheme.

Science.gov (United States)

Peura, J; Kempe, R; Strandén, I; Rydhmer, L

2016-12-01

The profit and production of an average Finnish blue fox farm was simulated using a deterministic bio-economic farm model. Risk was included using Arrow-Prat absolute risk aversion coefficient and profit variance. Risk-rated economic values were calculated for pregnancy rate, litter loss, litter size, pelt size, pelt quality, pelt colour clarity, feed efficiency and eye infection. With high absolute risk aversion, economic values were lower than with low absolute risk aversion. Economic values were highest for litter loss (18.16 and 26.42 EUR), litter size (13.27 and 19.40 EUR), pregnancy (11.99 and 18.39 EUR) and eye infection (12.39 and 13.81 EUR). Sensitivity analysis showed that selection pressure for improved eye health depended strongly on proportion of culled animals among infected animals and much less on the proportion of infected animals. The economic value of feed efficiency was lower than expected (6.06 and 8.03 EUR). However, it was almost the same magnitude as pelt quality (7.30 and 7.30 EUR) and higher than the economic value of pelt size (3.37 and 5.26 EUR). Risk factors should be considered in blue fox breeding scheme because they change the relative importance of traits. © 2016 Blackwell Verlag GmbH.

Excitation of lateral habenula neurons as a neural mechanism underlying ethanol-induced conditioned taste aversion.

Science.gov (United States)

Tandon, Shashank; Keefe, Kristen A; Taha, Sharif A

2017-02-15

The lateral habenula (LHb) has been implicated in regulation of drug-seeking behaviours through aversion-mediated learning. In this study, we recorded neuronal activity in the LHb of rats during an operant task before and after ethanol-induced conditioned taste aversion (CTA) to saccharin. Ethanol-induced CTA caused significantly higher baseline firing rates in LHb neurons, as well as elevated firing rates in response to cue presentation, lever press and saccharin taste. In a separate cohort of rats, we found that bilateral LHb lesions blocked ethanol-induced CTA. Our results strongly suggest that excitation of LHb neurons is required for ethanol-induced CTA, and point towards a mechanism through which LHb firing may regulate voluntary ethanol consumption. Ethanol, like other drugs of abuse, has both rewarding and aversive properties. Previous work suggests that sensitivity to ethanol's aversive effects negatively modulates voluntary alcohol intake and thus may be important in vulnerability to developing alcohol use disorders. We previously found that rats with lesions of the lateral habenula (LHb), which is implicated in aversion-mediated learning, show accelerated escalation of voluntary ethanol consumption. To understand neural encoding in the LHb contributing to ethanol-induced aversion, we recorded neural firing in the LHb of freely behaving, water-deprived rats before and after an ethanol-induced (1.5 g kg -1 20% ethanol, i.p.) conditioned taste aversion (CTA) to saccharin taste. Ethanol-induced CTA strongly decreased motivation for saccharin in an operant task to obtain the tastant. Comparison of LHb neural firing before and after CTA induction revealed four main differences in firing properties. First, baseline firing after CTA induction was significantly higher. Second, firing evoked by cues signalling saccharin availability shifted from a pattern of primarily inhibition before CTA to primarily excitation after CTA induction. Third, CTA induction reduced

Negative learning bias is associated with risk aversion in a genetic animal model of depression.

Science.gov (United States)

Shabel, Steven J; Murphy, Ryan T; Malinow, Roberto

2014-01-01

The lateral habenula (LHb) is activated by aversive stimuli and the omission of reward, inhibited by rewarding stimuli and is hyperactive in helpless rats-an animal model of depression. Here we test the hypothesis that congenital learned helpless (cLH) rats are more sensitive to decreases in reward size and/or less sensitive to increases in reward than wild-type (WT) control rats. Consistent with the hypothesis, we found that cLH rats were slower to switch preference between two responses after a small upshift in reward size on one of the responses but faster to switch their preference after a small downshift in reward size. cLH rats were also more risk-averse than WT rats-they chose a response delivering a constant amount of reward ("safe" response) more often than a response delivering a variable amount of reward ("risky" response) compared to WT rats. Interestingly, the level of bias toward negative events was associated with the rat's level of risk aversion when compared across individual rats. cLH rats also showed impaired appetitive Pavlovian conditioning but more accurate responding in a two-choice sensory discrimination task. These results are consistent with a negative learning bias and risk aversion in cLH rats, suggesting abnormal processing of rewarding and aversive events in the LHb of cLH rats.

Serotonin selectively influences moral judgment and behavior through effects on harm aversion.

Science.gov (United States)

Crockett, Molly J; Clark, Luke; Hauser, Marc D; Robbins, Trevor W

2010-10-05

Aversive emotional reactions to real or imagined social harms infuse moral judgment and motivate prosocial behavior. Here, we show that the neurotransmitter serotonin directly alters both moral judgment and behavior through increasing subjects' aversion to personally harming others. We enhanced serotonin in healthy volunteers with citalopram (a selective serotonin reuptake inhibitor) and contrasted its effects with both a pharmacological control treatment and a placebo on tests of moral judgment and behavior. We measured the drugs' effects on moral judgment in a set of moral 'dilemmas' pitting utilitarian outcomes (e.g., saving five lives) against highly aversive harmful actions (e.g., killing an innocent person). Enhancing serotonin made subjects more likely to judge harmful actions as forbidden, but only in cases where harms were emotionally salient. This harm-avoidant bias after citalopram was also evident in behavior during the ultimatum game, in which subjects decide to accept or reject fair or unfair monetary offers from another player. Rejecting unfair offers enforces a fairness norm but also harms the other player financially. Enhancing serotonin made subjects less likely to reject unfair offers. Furthermore, the prosocial effects of citalopram varied as a function of trait empathy. Individuals high in trait empathy showed stronger effects of citalopram on moral judgment and behavior than individuals low in trait empathy. Together, these findings provide unique evidence that serotonin could promote prosocial behavior by enhancing harm aversion, a prosocial sentiment that directly affects both moral judgment and moral behavior.

Auditory-visual aversive stimuli modulate the conscious experience of fear.

Science.gov (United States)

Taffou, Marine; Guerchouche, Rachid; Drettakis, George; Viaud-Delmon, Isabelle

2013-01-01

In a natural environment, affective information is perceived via multiple senses, mostly audition and vision. However, the impact of multisensory information on affect remains relatively undiscovered. In this study, we investigated whether the auditory-visual presentation of aversive stimuli influences the experience of fear. We used the advantages of virtual reality to manipulate multisensory presentation and to display potentially fearful dog stimuli embedded in a natural context. We manipulated the affective reactions evoked by the dog stimuli by recruiting two groups of participants: dog-fearful and non-fearful participants. The sensitivity to dog fear was assessed psychometrically by a questionnaire and also at behavioral and subjective levels using a Behavioral Avoidance Test (BAT). Participants navigated in virtual environments, in which they encountered virtual dog stimuli presented through the auditory channel, the visual channel or both. They were asked to report their fear using Subjective Units of Distress. We compared the fear for unimodal (visual or auditory) and bimodal (auditory-visual) dog stimuli. Dog-fearful participants as well as non-fearful participants reported more fear in response to bimodal audiovisual compared to unimodal presentation of dog stimuli. These results suggest that fear is more intense when the affective information is processed via multiple sensory pathways, which might be due to a cross-modal potentiation. Our findings have implications for the field of virtual reality-based therapy of phobias. Therapies could be refined and improved by implicating and manipulating the multisensory presentation of the feared situations.

Internet Filtering Technology and Aversive Online Experiences in Adolescents.

Science.gov (United States)

Przybylski, Andrew K; Nash, Victoria

2017-05-01

To evaluate the effectiveness of Internet filtering tools designed to shield adolescents from aversive experiences online. A total of 1030 in-home interviews were conducted with early adolescents aged from 12 to 15 years (M = 13.50, SD = 1.18) and their caregivers. Caregivers were asked about their use of Internet filtering and adolescent participants were interviewed about their recent online experiences. Contrary to our hypotheses, policy, and industry advice regarding the assumed benefits of filtering we found convincing evidence that Internet filters were not effective at shielding early adolescents from aversive online experiences. Preregistered prospective and randomised controlled trials are needed to determine the extent to which Internet filtering technology supports vs thwarts young people online and if their widespread use justifies their financial and informational costs. Copyright © 2017 Elsevier Inc. All rights reserved.

Conflict and disfluency as aversive signals: context-specific processing adjustments are modulated by affective location associations.

Science.gov (United States)

Dreisbach, Gesine; Reindl, Anna-Lena; Fischer, Rico

2018-03-01

Context-specific processing adjustments are one signature feature of flexible human action control. However, up to now the precise mechanisms underlying these adjustments are not fully understood. Here it is argued that aversive signals produced by conflict- or disfluency-experience originally motivate such context-specific processing adjustments. We tested whether the efficiency of the aversive conflict signal for control adaptation depends on the affective nature of the context it is presented in. In two experiments, high vs. low proportions of aversive signals (Experiment 1: conflict trials; Experiment 2: disfluent trials) were presented either above or below the screen center. This location manipulation was motivated by existing evidence that verticality is generally associated with affective valence with up being positive and down being negative. From there it was hypothesized that the aversive signals would lose their trigger function for processing adjustments when presented at the lower (i.e., more negative) location. This should then result in a reduced context-specific proportion effect when the high proportion of aversive signals was presented at the lower location. Results fully confirmed the predictions. In both experiments, the location-specific proportion effects were only present when the high proportion of aversive signals occurred at the more positive location above but were reduced (Experiment 1) or even eliminated (Experiment 2) when the high proportion occurred at the more negative location below. This interaction of processing adjustments with affective background contexts can thus be taken as further hint for an affective origin of control adaptations.

Shared risk aversion in spontaneous and induced abortion.

Science.gov (United States)

Catalano, Ralph; Bruckner, Tim A; Karasek, Deborah; Adler, Nancy E; Mortensen, Laust H

2016-05-01

Does the incidence of spontaneous abortion correlate positively over conception cohorts with the incidence of non-clinically indicated induced abortion as predicted by shared risk aversion? We find that the number of spontaneous and non-clinically indicated induced abortions correlates in conception cohorts, suggesting that risk aversion affects both the conscious and non-conscious mechanisms that control parturition. Much literature speculates that natural selection conserved risk aversion because the trait enhanced Darwinian fitness. Risk aversion, moreover, supposedly influences all decisions including those that individuals can and cannot report making. We argue that these circumstances, if real, would manifest in conscious and non-conscious decisions to invest in prospective offspring, and therefore affect incidence of induced and spontaneous abortion over time. Using data from Denmark, we test the hypothesis that monthly conception cohorts yielding unexpectedly many non-clinically indicated induced abortions also yield unexpectedly many spontaneous abortions. The 180 month test period (January 1995 through December 2009), yielded 1 351 800 gestations including 156 780 spontaneous as well as 233 280 induced abortions 9100 of which were clinically indicated. We use Box-Jenkins transfer functions to adjust the incidence of spontaneous and non-clinically indicated induced abortions for autocorrelation (including seasonality), cohort size, and fetal as well as gestational anomalies over the 180-month test period. We use cross-correlation to test our hypothesized association. We find a positive association between spontaneous and non-clinically indicated induced abortions. This suggests, consistent with our theory, that mothers of conception cohorts that yielded more spontaneous abortions than expected opted more frequently than expected for non-clinically indicated induced abortion. Limitations of our work include that even the world's best registration system

Motivational state controls the prediction error in Pavlovian appetitive-aversive interactions.

Science.gov (United States)

Laurent, Vincent; Balleine, Bernard W; Westbrook, R Frederick

2018-01-01

Contemporary theories of learning emphasize the role of a prediction error signal in driving learning, but the nature of this signal remains hotly debated. Here, we used Pavlovian conditioning in rats to investigate whether primary motivational and emotional states interact to control prediction error. We initially generated cues that positively or negatively predicted an appetitive food outcome. We then assessed how these cues modulated aversive conditioning when a novel cue was paired with a foot shock. We found that a positive predictor of food enhances, whereas a negative predictor of that same food impairs, aversive conditioning. Critically, we also showed that the enhancement produced by the positive predictor is removed by reducing the value of its associated food. In contrast, the impairment triggered by the negative predictor remains insensitive to devaluation of its associated food. These findings provide compelling evidence that the motivational value attributed to a predicted food outcome can directly control appetitive-aversive interactions and, therefore, that motivational processes can modulate emotional processes to generate the final error term on which subsequent learning is based. Copyright © 2017 Elsevier Inc. All rights reserved.

Emotion regulation reduces loss aversion and decreases amygdala responses to losses.

Science.gov (United States)

Sokol-Hessner, Peter; Camerer, Colin F; Phelps, Elizabeth A

2013-03-01

Emotion regulation strategies can alter behavioral and physiological responses to emotional stimuli and the neural correlates of those responses in regions such as the amygdala or striatum. The current study investigates the brain systems engaged when using an emotion regulation technique during financial decisions. In decision making, regulating emotion with reappraisal-focused strategies that encourage taking a different perspective has been shown to reduce loss aversion as observed both in choices and in the relative arousal responses to actual loss and gain outcomes. In the current study, we find using fMRI that behavioral loss aversion correlates with amygdala activity in response to losses relative to gains. Success in regulating loss aversion also correlates with the reduction in amygdala responses to losses but not to gains. Furthermore, across both decisions and outcomes, we find the reappraisal strategy increases baseline activity in dorsolateral and ventromedial prefrontal cortex and the striatum. The similarity of the neural circuitry observed to that seen in emotion regulation, despite divergent tasks, serves as further evidence for a role of emotion in decision making, and for the power of reappraisal to change assessments of value and thereby choices.

A Representation Theorem for Guilt Aversion

OpenAIRE

Jensen, Martin Kaae; Kozlovskaya, Maria

2016-01-01

Guilt aversion has been shown to play an important role in economic decision-making. In this paper, we take an axiomatic approach to guilt by deducing a utility representation from a list of easily interpretable assumptions on an agent's preferences. It turns out that our logarithmic representation can mitigate the problem of multiplicity of equilibria to which psychological games are prone. We apply the model in three well-known games and show that its predictions are consistent with experim...

Memory trace in feeding neural circuitry underlying conditioned taste aversion in Lymnaea.

Directory of Open Access Journals (Sweden)

Etsuro Ito

Full Text Available BACKGROUND: The pond snail Lymnaea stagnalis can maintain a conditioned taste aversion (CTA as a long-term memory. Previous studies have shown that the inhibitory postsynaptic potential (IPSP evoked in the neuron 1 medial (N1M cell by activation of the cerebral giant cell (CGC in taste aversion-trained snails was larger and lasted longer than that in control snails. The N1M cell is one of the interneurons in the feeding central pattern generator (CPG, and the CGC is a key regulatory neuron for the feeding CPG. METHODOLOGY/PRINCIPLE FINDINGS: Previous studies have suggested that the neural circuit between the CGC and the N1M cell consists of two synaptic connections: (1 the excitatory connection from the CGC to the neuron 3 tonic (N3t cell and (2 the inhibitory connection from the N3t cell to the N1M cell. However, because the N3t cell is too small to access consistently by electrophysiological methods, in the present study the synaptic inputs from the CGC to the N3t cell and those from the N3t cell to the N1M cell were monitored as the monosynaptic excitatory postsynaptic potential (EPSP recorded in the large B1 and B3 motor neurons, respectively. The evoked monosynaptic EPSPs of the B1 motor neurons in the brains isolated from the taste aversion-trained snails were identical to those in the control snails, whereas the spontaneous monosynaptic EPSPs of the B3 motor neurons were significantly enlarged. CONCLUSION/SIGNIFICANCE: These results suggest that, after taste aversion training, the monosynaptic inputs from the N3t cell to the following neurons including the N1M cell are specifically facilitated. That is, one of the memory traces for taste aversion remains as an increase in neurotransmitter released from the N3t cell. We thus conclude that the N3t cell suppresses the N1M cell in the feeding CPG, in response to the conditioned stimulus in Lymnaea CTA.

Memory trace in feeding neural circuitry underlying conditioned taste aversion in Lymnaea.

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Ito, Etsuro; Otsuka, Emi; Hama, Noriyuki; Aonuma, Hitoshi; Okada, Ryuichi; Hatakeyama, Dai; Fujito, Yutaka; Kobayashi, Suguru

2012-01-01

The pond snail Lymnaea stagnalis can maintain a conditioned taste aversion (CTA) as a long-term memory. Previous studies have shown that the inhibitory postsynaptic potential (IPSP) evoked in the neuron 1 medial (N1M) cell by activation of the cerebral giant cell (CGC) in taste aversion-trained snails was larger and lasted longer than that in control snails. The N1M cell is one of the interneurons in the feeding central pattern generator (CPG), and the CGC is a key regulatory neuron for the feeding CPG. Previous studies have suggested that the neural circuit between the CGC and the N1M cell consists of two synaptic connections: (1) the excitatory connection from the CGC to the neuron 3 tonic (N3t) cell and (2) the inhibitory connection from the N3t cell to the N1M cell. However, because the N3t cell is too small to access consistently by electrophysiological methods, in the present study the synaptic inputs from the CGC to the N3t cell and those from the N3t cell to the N1M cell were monitored as the monosynaptic excitatory postsynaptic potential (EPSP) recorded in the large B1 and B3 motor neurons, respectively. The evoked monosynaptic EPSPs of the B1 motor neurons in the brains isolated from the taste aversion-trained snails were identical to those in the control snails, whereas the spontaneous monosynaptic EPSPs of the B3 motor neurons were significantly enlarged. These results suggest that, after taste aversion training, the monosynaptic inputs from the N3t cell to the following neurons including the N1M cell are specifically facilitated. That is, one of the memory traces for taste aversion remains as an increase in neurotransmitter released from the N3t cell. We thus conclude that the N3t cell suppresses the N1M cell in the feeding CPG, in response to the conditioned stimulus in Lymnaea CTA.

Imagery Rescripting: The Impact of Conceptual and Perceptual Changes on Aversive Autobiographical Memories.

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Christien Slofstra

Full Text Available Imagery rescripting (ImRs is a process by which aversive autobiographical memories are rendered less unpleasant or emotional. ImRs is thought only to be effective if a change in the meaning-relevant (semantic content of the mental image is produced, according to a cognitive hypothesis of ImRs. We propose an additional hypothesis: that ImRs can also be effective by the manipulation of perceptual features of the memory, without explicitly targeting meaning-relevant content.In two experiments using a within-subjects design (both N = 48, community samples, both Conceptual-ImRs-focusing on changing meaning-relevant content-and Perceptual-ImRs-focusing on changing perceptual features-were compared to Recall-only of aversive autobiographical image-based memories. An active control condition, Recall + Attentional Breathing (Recall+AB was added in the first experiment. In the second experiment, a Positive-ImRs condition was added-changing the aversive image into a positive image that was unrelated to the aversive autobiographical memory. Effects on the aversive memory's unpleasantness, vividness and emotionality were investigated.In Experiment 1, compared to Recall-only, both Conceptual-ImRs and Perceptual-ImRs led to greater decreases in unpleasantness, and Perceptual-ImRs led to greater decreases in emotionality of memories. In Experiment 2, the effects on unpleasantness were not replicated, and both Conceptual-ImRs and Perceptual-ImRs led to greater decreases in emotionality, compared to Recall-only, as did Positive-ImRs. There were no effects on vividness, and the ImRs conditions did not differ significantly from Recall+AB.Results suggest that, in addition to traditional forms of ImRs, targeting the meaning-relevant content of an image during ImRs, relatively simple techniques focusing on perceptual aspects or positive imagery might also yield benefits. Findings require replication and extension to clinical samples.

Imagery Rescripting: The Impact of Conceptual and Perceptual Changes on Aversive Autobiographical Memories.

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Slofstra, Christien; Nauta, Maaike H; Holmes, Emily A; Bockting, Claudi L H

2016-01-01

Imagery rescripting (ImRs) is a process by which aversive autobiographical memories are rendered less unpleasant or emotional. ImRs is thought only to be effective if a change in the meaning-relevant (semantic) content of the mental image is produced, according to a cognitive hypothesis of ImRs. We propose an additional hypothesis: that ImRs can also be effective by the manipulation of perceptual features of the memory, without explicitly targeting meaning-relevant content. In two experiments using a within-subjects design (both N = 48, community samples), both Conceptual-ImRs-focusing on changing meaning-relevant content-and Perceptual-ImRs-focusing on changing perceptual features-were compared to Recall-only of aversive autobiographical image-based memories. An active control condition, Recall + Attentional Breathing (Recall+AB) was added in the first experiment. In the second experiment, a Positive-ImRs condition was added-changing the aversive image into a positive image that was unrelated to the aversive autobiographical memory. Effects on the aversive memory's unpleasantness, vividness and emotionality were investigated. In Experiment 1, compared to Recall-only, both Conceptual-ImRs and Perceptual-ImRs led to greater decreases in unpleasantness, and Perceptual-ImRs led to greater decreases in emotionality of memories. In Experiment 2, the effects on unpleasantness were not replicated, and both Conceptual-ImRs and Perceptual-ImRs led to greater decreases in emotionality, compared to Recall-only, as did Positive-ImRs. There were no effects on vividness, and the ImRs conditions did not differ significantly from Recall+AB. Results suggest that, in addition to traditional forms of ImRs, targeting the meaning-relevant content of an image during ImRs, relatively simple techniques focusing on perceptual aspects or positive imagery might also yield benefits. Findings require replication and extension to clinical samples.

Some aversive characteristics of centrifugally generated gravity.

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Altman, F.

1973-01-01

The effective weight of rats was manipulated by centrifugation. Two effective weight levels were obtained. In three escape avoidance conditions a lever press produced a change from a base level of 2.1 g to a response level of 1.1 g. In a punishment condition a response produced a change from a 1.1 g level to a 2.1 g level and in an extinction condition responses had no effect on the 2.1 g effective weight level present. All changes took 30 sec and were maintained for an additional 10 sec before a return to base level was initiated. When responses occurred closer together than the 40 sec, they delayed the return to base level by 40 sec. This 40 sec interval is referred to as response-contingent-time. The response rate and amount of response-contingent-time served as the data. The results confirmed previous data that centrifugation is aversive. The results are interpreted as indicating that the aversiveness is attributable to the increase in effective weight, and that rats can discriminate the different angular velocity-radius of rotation combinations used.

Loss Aversion and the Asymmetric Transmission of Monetary Policy

DEFF Research Database (Denmark)

Santoro, Emiliano; Petrella, Ivan; Pfajfar, Damjan

2014-01-01

depends on consumption deviations from a reference level below which loss aversion is displayed. State-dependent degrees of real rigidity and elasticity of intertemporal substitution in consumption generate competing effects on output and inflation. Contractions face the Central Bank with higher...

Risk Aversion and Public Reporting. Part 1: Observations From Cardiac Surgery and Interventional Cardiology.

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Shahian, David M; Jacobs, Jeffrey P; Badhwar, Vinay; D'Agostino, Richard S; Bavaria, Joseph E; Prager, Richard L

2017-12-01

Risk aversion is a potential unintended consequence of health care public reporting. In Part 1 of this review, four possible consequences of this phenomenon are discussed, including the denial of interventions to some high-risk patients, stifling of innovation, appropriate avoidance of futile interventions, and better matching of high-risk patients to more capable providers. We also summarize relevant observational clinical reports and survey results from cardiovascular medicine and surgery, the two specialties from which almost all risk aversion observations have been derived. Although these demonstrate that risk aversion does occur, the empirical data are much more consistent and compelling for interventional cardiology than for cardiac surgery. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Failure of Serial Taste-Taste Compound Presentations to Produce Overshadowing of Extinction of Conditioned Taste Aversion

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Pineno, Oskar

2010-01-01

Two experiments were conducted to study overshadowing of extinction in a conditioned taste aversion preparation. In both experiments, aversive conditioning with sucrose was followed by extinction treatment with either sucrose alone or in compound with another taste, citric acid. Experiment 1 employed a simultaneous compound extinction treatment…

Egr-1 induction provides a genetic response to food aversion in zebrafish

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Brigitte eBoyer

2013-05-01

Full Text Available As soon as zebrafish larvae start eating, they exhibit a marked aversion for bitter and acidic substances, as revealed by a consumption assay, in which fluorescent Tetrahymena serve as a feeding basis, to which various stimuli can be added. Bitter and acidic substances elicited an increase in mRNA accumulation of the immediate-early response gene egr-1, as revealed by in situ hybridization. Conversely, chemostimulants that did not induce aversion did not induce egr-1 response. Maximum labelling was observed in cells located in the oropharyngeal cavity and on the gill rakers. Gustatory areas of the brain were also labelled. Interestingly, when bitter tastants were repeatedly associated with food reward, zebrafish juveniles learned to ingest food in the presence of the bitter compound. After habituation, the acquisition of acceptance for bitterness was accompanied by a loss of egr-1 labelling. Altogether, our data indicate that egr-1 participates specifically in food aversion. The existence of reward-coupled changes in taste sensitivity in humans suggests that our results are relevant to situations in humans.

Egr-1 induction provides a genetic response to food aversion in zebrafish.

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Boyer, Brigitte; Ernest, Sylvain; Rosa, Frédéric

2013-01-01

As soon as zebrafish larvae start eating, they exhibit a marked aversion for bitter and acidic substances, as revealed by a consumption assay, in which fluorescent Tetrahymena serve as a feeding basis, to which various stimuli can be added. Bitter and acidic substances elicited an increase in mRNA accumulation of the immediate-early response gene egr-1, as revealed by in situ hybridization. Conversely, chemostimulants that did not induce aversion did not induce egr-1 response. Maximum labeling was observed in cells located in the oropharyngeal cavity and on the gill rakers. Gustatory areas of the brain were also labeled. Interestingly, when bitter tastants were repeatedly associated with food reward, zebrafish juveniles learned to ingest food in the presence of the bitter compound. After habituation, the acquisition of acceptance for bitterness was accompanied by a loss of egr-1 labeling. Altogether, our data indicate that egr-1 participates specifically in food aversion. The existence of reward-coupled changes in taste sensitivity in humans suggests that our results are relevant to situations in humans.

On the robustness and possible accounts of ambiguity aversion

NARCIS (Netherlands)

Keren, G.; Gerritsen, L.E.M.

1999-01-01

Ambiguity aversion is one of the most robust phenomena documented in the decision making literature, though there are still disagreements concerning what constitutes an adequate account for its occurrence. We describe six experiments that shed additional light on the enigmatic phenomenon of

Differential effects of beta-adrenergic receptor blockade in the medial prefrontal cortex during aversive and incidental taste memory formation.

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Reyes-López, J; Nuñez-Jaramillo, L; Morán-Guel, E; Miranda, M I

2010-08-11

The medial prefrontal cortex (mPFC) is a brain area crucial for memory, attention, and decision making. Specifically, the noradrenergic system in this cortex is involved in aversive learning, as well as in the retrieval of these memories. Some evidence suggests that this area has an important role during taste memory, particularly during conditioned taste aversion (CTA), a model of aversive memory. Despite some previous evidence, there is scarce information about the role of adrenergic receptors in the mPFC during formation of aversive taste memory and appetitive/incidental taste memory. The goal of this research was to evaluate the role of mPFC beta-adrenergic receptors during CTA acquisition/consolidation or CTA retrieval, as well as during incidental taste memory formation using the model of latent inhibition of CTA. The results showed that infusions in the mPFC of the beta-adrenergic antagonist propranolol before CTA acquisition impaired both short- and long-term aversive taste memory formation, and also that propranolol infusions before the memory test impaired CTA retrieval. However, propranolol infusions before pre-exposure to the taste during the latent inhibition procedure had no effect on incidental taste memory acquisition or consolidation. These data indicate that beta-adrenergic receptors in the mPFC have different functions during taste memory formation: they have an important role during aversive taste association as well as during aversive retrieval but not during incidental taste memory formation. Copyright (c) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

Modeling Inequity Aversion in a Dictator Game with Production

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Ismael Rodriguez-Lara

2012-10-01

Full Text Available We expand upon the previous models of inequity aversion of Fehr and Schmidt [1], and Frohlich et al. [2], which assume that dictators get disutility if the final allocation of surplus deviates from the equal split (egalitarian principle or from the subjects' production (libertarian principle. In our model, dictators may also account for the way in which the surplus was generated. More precisely, our model incorporates the idea of liberal egalitarian ethics into the analysis, making it possible for dictators to divide the surplus according to the accountability principle, which states that subjects should only be rewarded for factors under their control. This fairness ideal does not hold subjects responsible for factors beyond their control in the production of the surplus, an idea that is absent in the models of inequity aversion cited above (JEL Codes: D3, D6, D63.

Fos and Egr1 Expression in the Rat Brain in Response to Olfactory Cue after Taste-Potentiated Odor Aversion Retrieval

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Cattarelli, Martine; Dardou, David; Datiche, Frederique

2006-01-01

When an odor is paired with a delayed illness, rats acquire a relatively weak odor aversion. In contrast, rats develop a strong aversion to an olfactory cue paired with delayed illness if it is presented simultaneously with a gustatory cue. Such a conditioning effect has been referred to as taste-potentiated odor aversion learning (TPOA). TPOA is…

Coordinating a Supply Chain with a Loss-Averse Retailer and Effort Dependent Demand

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Li, Liying

2014-01-01

This study investigates the channel coordination issue of a supply chain with a risk-neutral manufacturer and a loss-averse retailer facing stochastic demand that is sensitive to sales effort. Under the loss-averse newsvendor setting, a distribution-free gain/loss-sharing-and-buyback (GLB) contract has been shown to be able to coordinate the supply chain. However, we find that a GLB contract remains ineffective in managing the supply chain when retailer sales efforts influence the demand. To effectively coordinate the channel, we propose to combine a GLB contract with sales rebate and penalty (SRP) contract. In addition, we discover a special class of gain/loss contracts that can coordinate the supply chain and arbitrarily allocate the expected supply chain profit between the manufacturer and the retailer. We then analyze the effect of loss aversion on the retailer's decision-making behavior and supply chain performance. Finally, we perform a numerical study to illustrate the findings and gain additional insights. PMID:25197696

Coordinating a supply chain with a loss-averse retailer and effort dependent demand.

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Li, Liying; Wang, Yong

2014-01-01

This study investigates the channel coordination issue of a supply chain with a risk-neutral manufacturer and a loss-averse retailer facing stochastic demand that is sensitive to sales effort. Under the loss-averse newsvendor setting, a distribution-free gain/loss-sharing-and-buyback (GLB) contract has been shown to be able to coordinate the supply chain. However, we find that a GLB contract remains ineffective in managing the supply chain when retailer sales efforts influence the demand. To effectively coordinate the channel, we propose to combine a GLB contract with sales rebate and penalty (SRP) contract. In addition, we discover a special class of gain/loss contracts that can coordinate the supply chain and arbitrarily allocate the expected supply chain profit between the manufacturer and the retailer. We then analyze the effect of loss aversion on the retailer's decision-making behavior and supply chain performance. Finally, we perform a numerical study to illustrate the findings and gain additional insights.

Loss-Averse Inventory and Borrowing Decisions with Constraints on Working Capital in Fashion and Textiles Industry

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Lijun Ma

2013-01-01

Full Text Available Traditional inventory models focus on operational decisions and inventory control. Quite few models consider the financial constraint and decision bias such as loss aversion, which are the reality in today's business environment, especially for the fashion and textiles industry. In this paper we study the inventory control problem for a loss-averse retailer with financial constraint for operations in a periodic review setting in a finite horizon. We characterize the optimal inventory control policies with self-financing or with borrowing as capital-dependent base-stock policies. We demonstrate with numerical examples that the optimal base-stock level is nonincreasing in the accumulated wealth and the loss-aversion indicator.

Identification of risk aversion factor for radiation workers in Korea

International Nuclear Information System (INIS)

Fadul, Abdulbagi; Na, Seong H.

2016-01-01

Radiation aversion factor reflects the degree of avoidance of radiation exposure which is considered a fundamental element in the optimization of radiation protection and a key factor in determining the real monetary value of the man-Sievert (Sv). This study provides an adjusted risk aversion factor, which was prescribed by the Korea Institute for Nuclear Safety (KINS), a regulatory body in Korea. Specifically, the Korea Hydro and Nuclear Power Co., Ltd. (KHNP) evaluated the monetary value of the man-Sv for Korean Nuclear Power Plants (NPPs) workers. This monetary value was assessed by the radiation aversion factor. Consequently, identifying the monetary value of the man-Sv in this study will enhance not only the effectiveness of optimization of radiation protection in Korea but also contribute to reduce doses to As Low As Reasonably Achievable (ALARA) when accounting for economic and societal aspects. The primary purpose of this study is to obtain the risk aversion factor for radiation workers in medical and industrial facilities in Korea. The secondary purpose is to evaluate the real monetary value of the man-Sv.These objectives will be accomplished by collecting data from surveys that consider a variety of socio-economic conditions. The value of 1.45 represents considerable avoidance of radiation risk for the majority of NDT radiographers due to familiarity and work experience with radiation hazards. On the other hand, the value 1.57 indicates that most of radiation medical practitioners, in particular, interventional radiologists have a strong will to avoid radiation risk. However, they will accept more risk with incremental salary increases. For international comparison, the concept of Purchasing Power Parity (PPP) should be adopted to obtain the alpha values in real term. Certainly, this monetary value of the man-Sv is expected to contribute effectively in optimization of radiation protection in both medical and industrial fields. The findings of this study

Dismissing Attachment Characteristics Dynamically Modulate Brain Networks Subserving Social Aversion.

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Krause, Anna Linda; Borchardt, Viola; Li, Meng; van Tol, Marie-José; Demenescu, Liliana Ramona; Strauss, Bernhard; Kirchmann, Helmut; Buchheim, Anna; Metzger, Coraline D; Nolte, Tobias; Walter, Martin

2016-01-01

Attachment patterns influence actions, thoughts and feeling through a person's "inner working model". Speech charged with attachment-dependent content was proposed to modulate the activation of cognitive-emotional schemata in listeners. We performed a 7 Tesla rest-task-rest functional magnetic resonance imaging (fMRI)-experiment, presenting auditory narratives prototypical of dismissing attachment representations to investigate their effect on 23 healthy males. We then examined effects of participants' attachment style and childhood trauma on brain state changes using seed-based functional connectivity (FC) analyses, and finally tested whether subjective differences in responsivity to narratives could be predicted by baseline network states. In comparison to a baseline state, we observed increased FC in a previously described "social aversion network" including dorsal anterior cingulated cortex (dACC) and left anterior middle temporal gyrus (aMTG) specifically after exposure to insecure-dismissing attachment narratives. Increased dACC-seeded FC within the social aversion network was positively related to the participants' avoidant attachment style and presence of a history of childhood trauma. Anxious attachment style on the other hand was positively correlated with FC between the dACC and a region outside of the "social aversion network", namely the dorsolateral prefrontal cortex, which suggests decreased network segregation as a function of anxious attachment. Finally, the extent of subjective experience of friendliness towards the dismissing narrative was predicted by low baseline FC-values between hippocampus and inferior parietal lobule (IPL). Taken together, our study demonstrates an activation of networks related to social aversion in terms of increased connectivity after listening to insecure-dismissing attachment narratives. A causal interrelation of brain state changes and subsequent changes in social reactivity was further supported by our observation of

Identification of risk aversion factor for radiation workers in Korea

Energy Technology Data Exchange (ETDEWEB)

Fadul, Abdulbagi [KAIST, Daejeon (Korea, Republic of); Na, Seong H. [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

2016-10-15

Radiation aversion factor reflects the degree of avoidance of radiation exposure which is considered a fundamental element in the optimization of radiation protection and a key factor in determining the real monetary value of the man-Sievert (Sv). This study provides an adjusted risk aversion factor, which was prescribed by the Korea Institute for Nuclear Safety (KINS), a regulatory body in Korea. Specifically, the Korea Hydro and Nuclear Power Co., Ltd. (KHNP) evaluated the monetary value of the man-Sv for Korean Nuclear Power Plants (NPPs) workers. This monetary value was assessed by the radiation aversion factor. Consequently, identifying the monetary value of the man-Sv in this study will enhance not only the effectiveness of optimization of radiation protection in Korea but also contribute to reduce doses to As Low As Reasonably Achievable (ALARA) when accounting for economic and societal aspects. The primary purpose of this study is to obtain the risk aversion factor for radiation workers in medical and industrial facilities in Korea. The secondary purpose is to evaluate the real monetary value of the man-Sv.These objectives will be accomplished by collecting data from surveys that consider a variety of socio-economic conditions. The value of 1.45 represents considerable avoidance of radiation risk for the majority of NDT radiographers due to familiarity and work experience with radiation hazards. On the other hand, the value 1.57 indicates that most of radiation medical practitioners, in particular, interventional radiologists have a strong will to avoid radiation risk. However, they will accept more risk with incremental salary increases. For international comparison, the concept of Purchasing Power Parity (PPP) should be adopted to obtain the alpha values in real term. Certainly, this monetary value of the man-Sv is expected to contribute effectively in optimization of radiation protection in both medical and industrial fields. The findings of this study

Dismissing attachment characteristics dynamically modulate brain networks subserving social aversion.

Directory of Open Access Journals (Sweden)

Anna Linda eKrause

2016-03-01

Full Text Available Attachment patterns influence actions, thoughts and feeling through a person’s ‘Inner Working Model’. Speech charged with attachment-dependent content was proposed to modulate the activation of cognitive-emotional schemata in listeners. We performed a 7 Tesla rest-task-rest fMRI-experiment, presenting auditory narratives prototypical of dismissing attachment representations to investigate their effect on 23 healthy males. We then examined effects of participants’ attachment style and childhood trauma on brain state changes using seed-based functional connectivity (FC analyses, and finally tested whether subjective differences in responsivity to narratives could be predicted by baseline network states. In comparison to a baseline state, we observed increased FC in a previously described ‘social aversion network’ including dorsal anterior cingulated cortex (dACC and left anterior middle temporal gyrus (aMTG specifically after exposure to insecure-dismissing attachment narratives. Increased dACC-seeded FC within the social aversion network was positively related to the participants’ avoidant attachment style and presence of a history of childhood trauma. Anxious attachment style on the other hand was positively correlated with FC between the dACC and a region outside of the ‘social aversion network’, namely the dorsolateral prefrontal cortex, which suggests decreased network segregation as a function of anxious attachment. Finally, the extent of subjective experience of friendliness towards the dismissing narrative was predicted by low baseline FC-values between hippocampus and inferior parietal lobule. Taken together, our study demonstrates an activation of networks related to social aversion in terms of increased connectivity after listening to insecure-dismissing attachment narratives. A causal interrelation of brain state changes and subsequent changes in social reactivity was further supported by our observation of direct

Electricity capacity investment under risk aversion: A case study of coal, gas, and concentrated solar power

International Nuclear Information System (INIS)

Fan Lin; Norman, Catherine S.; Patt, Anthony G.

2012-01-01

The policy instrument many economists favor to reduce greenhouse gas emissions and to shift new investment towards low carbon technologies is the tradable allowance system. Experience with this instrument has been mixed, with a crucial design issue being the choice of whether to auction allowances to firms, or to grandfather them based on historical emissions. In this paper, we examine the changing incentives of investment in different technologies, when investors are risk averse and are expecting an allowance system with a certain allocation rule but do not know if the policy is going to take place in the near future. Investors also cannot fully predict future investment costs for the low-carbon technology. We apply a game theoretic model to examine the combined effects of uncertainty and risk aversion on the actions of potential investors into high and low carbon generating capacity, under both allocation rules and uncertain costs. We find that uncertainty and risk aversion do have implications towards investment incentives. We discuss policy implications of these findings. - Highlights: ► We examined capacity investments under alternative carbon permit allocation schemes. ► Uncertainty in future permit markets’ existence reduces investments into renewables. ► If permits are grandfathered, risk averse companies decrease renewable investment. ► Risk aversion minimizes the effects of uncertainty if carbon permits are auctioned.

Absolute Risk Aversion and the Returns to Education.

Science.gov (United States)

Brunello, Giorgio

2002-01-01

Uses 1995 Italian household income and wealth survey to measure individual absolute risk aversion of 1,583 married Italian male household heads. Uses this measure as an instrument for attained education in a standard-log earnings equation. Finds that the IV estimate of the marginal return to schooling is much higher than the ordinary least squares…

Mice do not develop conditioned taste aversion because of immunity loss.

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Vidal, Jose

2011-01-01

This study intends to test the generation of conditioned taste aversion and conditioned immunodepression by daily paired administration of saccharin solution with cyclophosphamide, 15 mg/kg, for 4 days. One group of male mice of the outbred CD1 strain drank 0.15% saccharin and received 1 injection of cyclophosphamide, 15 mg/kg, for 4 days (paired group), another group (unpaired group) received the same doses of saccharin and cyclophosphamide noncontingently, the third group (cy60) received saccharin paired with cyclophosphamide, 60 mg/kg, and the fourth group (placebo) received saccharin in the absence of cyclophosphamide. All mice were immunized with keyhole limpet hemocyanin (KLH), 0.2 mg, 1 day before the treatments. Mice of the paired, unpaired and cy60 groups displayed a similarly decreased antibody response to KLH, but mice of the paired group did not develop an aversion to saccharin while mice of the cy60 group did. Besides, repeat presentation of saccharin to mice of the paired group did not alter their antibody response to ovalbumin compared with mice of the unpaired or placebo group. Taste aversion was not elicited in response to impaired immunity and the conditioned stimulus (saccharin) did not impair the antibody response. 2011 S. Karger AG, Basel.

A note on testing guilt aversion

DEFF Research Database (Denmark)

Bellemare, Charles; Sebald, Alexander Christopher; Suetens, Sigrid

2017-01-01

We compare three approaches to test for guilt aversion in two economic experiments. The first approach elicits second-order beliefs using self-reports. The second approach discloses first-order beliefs of matched players to decision makers, which are taken as exogenous second-order beliefs...... of decision makers. The third approach lets decision makers make choices conditional on a sequence of possible first-order beliefs of matched players. We find that the first and third approach generate similar results, both qualitatively and quantitatively. The second approach, however, generates...

Effect of sex on ethanol consumption and conditioned taste aversion in adolescent and adult rats.

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Schramm-Sapyta, Nicole L; Francis, Reynold; MacDonald, Andrea; Keistler, Colby; O'Neill, Lauren; Kuhn, Cynthia M

2014-04-01

Vulnerability to alcoholism is determined by many factors, including the balance of pleasurable vs. aversive alcohol-induced sensations: pleasurable sensations increase intake, while aversive sensations decrease it. Female sex and adolescent age are associated with lower sensitivity to intake-reducing effects and more rapid development of alcohol abuse. This study assessed voluntary drinking and the aversive effects of alcohol to determine whether these measures are inversely related across the sexes and development. Voluntary drinking of 20 % ethanol in an every-other-day (EOD) availability pattern and the dose-response relationship of ethanol conditioned taste aversion (CTA) were assessed in male and female adolescent and adult rats. CTA was sex specific in adult but not adolescent rats, with adult females exhibiting less aversion. Voluntary ethanol consumption varied according to age and individual differences but was not sex specific. Adolescents initially drank more than adults, exhibited greater day-to-day variation in consumption, were more susceptible to the alcohol deprivation effect, and took longer to establish individual differences in consumption patterns. These results show that the emergence of intake patterns differs between adolescents and adults. Adolescents as a group initiate drinking at high levels but decrease intake as they mature. A subset of adolescents maintained high drinking levels into adulthood. In contrast, most adults consumed at steady, low levels, but a small subset quickly established and maintained high-consumption patterns. Adolescents also showed marked deprivation-induced increases. Sex differences were not observed in EOD drinking during either adolescence or adulthood.

Reward and aversion in a heterogeneous midbrain dopamine system.

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Lammel, Stephan; Lim, Byung Kook; Malenka, Robert C

2014-01-01

The ventral tegmental area (VTA) is a heterogeneous brain structure that serves a central role in motivation and reward processing. Abnormalities in the function of VTA dopamine (DA) neurons and the targets they influence are implicated in several prominent neuropsychiatric disorders including addiction and depression. Recent studies suggest that the midbrain DA system is composed of anatomically and functionally heterogeneous DA subpopulations with different axonal projections. These findings may explain a number of previously confusing observations that suggested a role for DA in processing both rewarding as well as aversive events. Here we will focus on recent advances in understanding the neural circuits mediating reward and aversion in the VTA and how stress as well as drugs of abuse, in particular cocaine, alter circuit function within a heterogeneous midbrain DA system. This article is part of a Special Issue entitled 'NIDA 40th Anniversary Issue'. Copyright © 2013 Elsevier Ltd. All rights reserved.

Drug-induced conditioned place preference and aversion in mice.

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Cunningham, Christopher L; Gremel, Christina M; Groblewski, Peter A

2006-01-01

This protocol describes the equipment and methods used to establish conditioned place preference (CPP) or aversion (CPA). Place conditioning is a form of Pavlovian conditioning routinely used to measure the rewarding or aversive motivational effects of objects or experiences (e.g., abused drugs). Here, we present a place conditioning procedure that has been used extensively to study the motivational effects of ethanol and other abused drugs in mice. This protocol involves three phases: (i) habituation (or a pretest), (ii) conditioning of an association between the drug and a tactile or visual stimulus and (iii) a test that offers a choice between the drug-associated cue and a neutral cue. If the drug has motivational significance, mice will spend significantly more time (CPP) or less time (CPA) in proximity to the drug-associated cue. Potential problems in the design and interpretation of place conditioning studies are discussed. A typical experiment lasts 2 weeks.

Cognitive decline is associated with risk aversion and temporal discounting in older adults without dementia.

Directory of Open Access Journals (Sweden)

Bryan D James

Full Text Available Risk aversion and temporal discounting are preferences that are strongly linked to sub-optimal financial and health decision making ability. Prior studies have shown they differ by age and cognitive ability, but it remains unclear whether differences are due to age-related cognitive decline or lower cognitive abilities over the life span. We tested the hypothesis that cognitive decline is associated with higher risk aversion and temporal discounting in 455 older persons without dementia from the Memory and Aging Project, a longitudinal cohort study of aging in Chicago. All underwent repeated annual cognitive evaluations using a detailed battery including 19 tests. Risk aversion was measured using standard behavioral economics questions: participants were asked to choose between a certain monetary payment versus a gamble in which they could gain more or nothing; potential gamble gains varied across questions. Temporal discounting: participants were asked to choose between an immediate, smaller payment and a delayed, larger one; two sets of questions addressed small and large stakes based on payment amount. Regression analyses were used to examine whether prior rate of cognitive decline predicted level of risk aversion and temporal discounting, controlling for age, sex, and education. Over an average of 5.5 (SD=2.9 years, cognition declined at an average of 0.016 units per year (SD=0.03. More rapid cognitive decline predicted higher levels of risk aversion (p=0.002 and temporal discounting (small stakes: p=0.01, high stakes: p=0.006. Further, associations between cognitive decline and risk aversion (p=0.015 and large stakes temporal discounting (p=0.026 persisted in analyses restricted to persons without any cognitive impairment (i.e., no dementia or mild cognitive impairment; the association of cognitive decline and small stakes temporal discounting was no longer statistically significant (p=0.078. These findings are consistent with the

Cognitive decline is associated with risk aversion and temporal discounting in older adults without dementia.

Science.gov (United States)

James, Bryan D; Boyle, Patricia A; Yu, Lei; Han, S Duke; Bennett, David A

2015-01-01

Risk aversion and temporal discounting are preferences that are strongly linked to sub-optimal financial and health decision making ability. Prior studies have shown they differ by age and cognitive ability, but it remains unclear whether differences are due to age-related cognitive decline or lower cognitive abilities over the life span. We tested the hypothesis that cognitive decline is associated with higher risk aversion and temporal discounting in 455 older persons without dementia from the Memory and Aging Project, a longitudinal cohort study of aging in Chicago. All underwent repeated annual cognitive evaluations using a detailed battery including 19 tests. Risk aversion was measured using standard behavioral economics questions: participants were asked to choose between a certain monetary payment versus a gamble in which they could gain more or nothing; potential gamble gains varied across questions. Temporal discounting: participants were asked to choose between an immediate, smaller payment and a delayed, larger one; two sets of questions addressed small and large stakes based on payment amount. Regression analyses were used to examine whether prior rate of cognitive decline predicted level of risk aversion and temporal discounting, controlling for age, sex, and education. Over an average of 5.5 (SD=2.9) years, cognition declined at an average of 0.016 units per year (SD=0.03). More rapid cognitive decline predicted higher levels of risk aversion (p=0.002) and temporal discounting (small stakes: p=0.01, high stakes: p=0.006). Further, associations between cognitive decline and risk aversion (p=0.015) and large stakes temporal discounting (p=0.026) persisted in analyses restricted to persons without any cognitive impairment (i.e., no dementia or mild cognitive impairment); the association of cognitive decline and small stakes temporal discounting was no longer statistically significant (p=0.078). These findings are consistent with the hypothesis that

Lossed in translation: an off-the-shelf method to recover probabilistic beliefs from loss-averse agents.

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Offerman, Theo; Palley, Asa B

2016-01-01

Strictly proper scoring rules are designed to truthfully elicit subjective probabilistic beliefs from risk neutral agents. Previous experimental studies have identified two problems with this method: (i) risk aversion causes agents to bias their reports toward the probability of [Formula: see text], and (ii) for moderate beliefs agents simply report [Formula: see text]. Applying a prospect theory model of risk preferences, we show that loss aversion can explain both of these behavioral phenomena. Using the insights of this model, we develop a simple off-the-shelf probability assessment mechanism that encourages loss-averse agents to report true beliefs. In an experiment, we demonstrate the effectiveness of this modification in both eliminating uninformative reports and eliciting true probabilistic beliefs.

Ethanol-induced conditioned taste aversion in Warsaw Alcohol High-Preferring (WHP) and Warsaw Alcohol Low-Preferring (WLP) rats.

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Dyr, Wanda; Wyszogrodzka, Edyta; Paterak, Justyna; Siwińska-Ziółkowska, Agnieszka; Małkowska, Anna; Polak, Piotr

2016-03-01

The aversive action of the pharmacological properties of ethanol was studied in selectively bred Warsaw Alcohol High-Preferring (WHP) and Warsaw Alcohol Low-Preferring (WLP) rats. For this study, a conditioned-taste aversion test was used. Male WHP and WLP rats were submitted to daily 20-min sessions for 5 days, in which a saccharin solution (1.0 g/L) was available (pre-conditioning phase). Next, this drinking was paired with the injection of ethanol (0, 0.5, 1.0 g/kg), intraperitoneally [i.p.] immediately after removal of the saccharin bottle (conditioning phase). Afterward, the choice between the saccharin solution and water was extended for 18 subsequent days for 20-min daily sessions (post-conditioning phase). Both doses of ethanol did not produce an aversion to saccharin in WLP and WHP rats in the conditioning phase. However, injection of the 1.0 g/kg dose of ethanol produced an aversion in WLP rats that was detected by a decrease in saccharin intake at days 1, 3, 7, and 10 of the post-conditioning phase, with a decrease in saccharin preference for 16 days of the post-conditioning phase. Conditioned taste aversion, measured as a decrease in saccharin intake and saccharin preference, was only visible in WHP rats at day 1 and day 3 of the post-conditioning phase. This difference between WLP and WHP rats was apparent despite similar blood ethanol levels in both rat lines following injection of 0.5 and 1.0 g/kg of ethanol. These results may suggest differing levels of aversion to the post-ingestional effects of ethanol between WLP and WHP rats. These differing levels of aversion may contribute to the selected line difference in ethanol preference in WHP and WLP rats. Copyright © 2016 Elsevier Inc. All rights reserved.

Relationship between vomiting and taste aversion learning in the ferret: studies with ionizing radiation, lithium chloride, and amphetamine.

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Rabin, B M; Hunt, W A

1992-09-01

The relationship between emesis and taste aversion learning was studied in ferrets (Mustela putorius furo) following exposure to ionizing radiation (50-200 cGy) or injection of lithium chloride (1.5-3.0 mEq/kg, ip). When 10% sucrose or 0.1% saccharin was used as the conditioned stimulus, neither unconditioned stimulus produced a taste aversion, even when vomiting was produced by the stimulus (Experiments 1 and 2). When a canned cat food was used as the conditioned stimulus, lithium chloride, but not ionizing radiation, produced a taste aversion (Experiment 3). Lithium chloride was effective in producing a conditioned taste aversion when administration of the toxin was delayed by up to 90 min following the ingestion of the canned cat food, indicating that the ferrets are capable of showing long-delay learning (Experiment 4). Experiment 5 examined the capacity of amphetamine, which is a qualitatively different stimulus than lithium chloride or ionizing radiation, to produce taste aversion learning in rats and cats as well as in ferrets. Injection of amphetamine (3 mg/kg, ip) produced a taste aversion in rats and cats but not in ferrets which required a higher dose (> 5 mg/kg). The results of these experiments are interpreted as indicating that, at least for the ferret, there is no necessary relationship between toxin-induced illness and the acquisition of a CTA and that gastrointestinal distress is not a sufficient condition for CTA learning.

Decomposing Self-Control:Individual Differences in Goal Pursuit Despite Interfering Aversion, Temptation, and Distraction

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Rosa eSteimke

2016-04-01

Full Text Available Self-control can be defined as the ability to exert control over ones impulses. Currently, most research in the area relies on self-report. Focusing on attentional control processes involved in self-control, we modified a spatial selective attentional cueing task to test three domains of self-control experimentally in one task using aversive, tempting, and neutral picture-distractors. The aims of the study were (1 to investigate individual differences in the susceptibility to aversive, tempting and neutral distraction within one paradigm and (2 to test the association of these three self-control domains to conventional measures of self-control including self-report. The final sample consisted of 116 participants. The task required participants to identify target letters E or F presented at a cued target location while the distractors were presented. Behavioral and eyetracking data were obtained during the performance of the task. High task performance was encouraged via monetary incentives. In addition to the attentional self-control task, self-reported self-control was assessed and participants performed a color Stroop task, an unsolvable anagram task and a delay of gratification task using chocolate sweets. We found that aversion, temptation, and neutral distraction were associated with significantly increased error rates, reaction times and gaze pattern deviations. Overall task performance on our task correlated with self-reported self-control ability. Measures of aversion, temptation, and distraction showed moderate split-half reliability, but did not correlate with each other across participants. Additionally, participants who made a self-controlled decision in the delay of gratification task were less distracted by temptations in our task than participants who made an impulsive choice. Our individual differences analyses suggest that (1 the ability to endure aversion, resist temptations and ignore neutral distractions are independent of

Understanding the Uncanny: Both Atypical Features and Category Ambiguity Provoke Aversion toward Humanlike Robots

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Megan K. Strait

2017-08-01

Full Text Available Robots intended for social contexts are often designed with explicit humanlike attributes in order to facilitate their reception by (and communication with people. However, observation of an “uncanny valley”—a phenomenon in which highly humanlike entities provoke aversion in human observers—has lead some to caution against this practice. Both of these contrasting perspectives on the anthropomorphic design of social robots find some support in empirical investigations to date. Yet, owing to outstanding empirical limitations and theoretical disputes, the uncanny valley and its implications for human-robot interaction remains poorly understood. We thus explored the relationship between human similarity and people's aversion toward humanlike robots via manipulation of the agents' appearances. To that end, we employed a picture-viewing task (Nagents = 60 to conduct an experimental test (Nparticipants = 72 of the uncanny valley's existence and the visual features that cause certain humanlike robots to be unnerving. Across the levels of human similarity, we further manipulated agent appearance on two dimensions, typicality (prototypic, atypical, and ambiguous and agent identity (robot, person, and measured participants' aversion using both subjective and behavioral indices. Our findings were as follows: (1 Further substantiating its existence, the data show a clear and consistent uncanny valley in the current design space of humanoid robots. (2 Both category ambiguity, and more so, atypicalities provoke aversive responding, thus shedding light on the visual factors that drive people's discomfort. (3 Use of the Negative Attitudes toward Robots Scale did not reveal any significant relationships between people's pre-existing attitudes toward humanlike robots and their aversive responding—suggesting positive exposure and/or additional experience with robots is unlikely to affect the occurrence of an uncanny valley effect in humanoid robotics

Decomposing Self-Control: Individual Differences in Goal Pursuit Despite Interfering Aversion, Temptation, and Distraction

Science.gov (United States)

Steimke, Rosa; Stelzel, Christine; Gaschler, Robert; Rothkirch, Marcus; Ludwig, Vera U.; Paschke, Lena M.; Trempler, Ima; Kathmann, Norbert; Goschke, Thomas; Walter, Henrik

2016-01-01

Self-control can be defined as the ability to exert control over ones impulses. Currently, most research in the area relies on self-report. Focusing on attentional control processes involved in self-control, we modified a spatial selective attentional cueing task to test three domains of self-control experimentally in one task using aversive, tempting, and neutral picture-distractors. The aims of the study were (1) to investigate individual differences in the susceptibility to aversive, tempting, and neutral distraction within one paradigm and (2) to test the association of these three self-control domains to conventional measures of self-control including self-report. The final sample consisted of 116 participants. The task required participants to identify target letters “E” or “F” presented at a cued target location while the distractors were presented. Behavioral and eyetracking data were obtained during the performance of the task. High task performance was encouraged via monetary incentives. In addition to the attentional self-control task, self-reported self-control was assessed and participants performed a color Stroop task, an unsolvable anagram task and a delay of gratification task using chocolate sweets. We found that aversion, temptation, and neutral distraction were associated with significantly increased error rates, reaction times and gaze pattern deviations. Overall task performance on our task correlated with self-reported self-control ability. Measures of aversion, temptation, and distraction showed moderate split-half reliability, but did not correlate with each other across participants. Additionally, participants who made a self-controlled decision in the delay of gratification task were less distracted by temptations in our task than participants who made an impulsive choice. Our individual differences analyses suggest that (1) the ability to endure aversion, resist temptations and ignore neutral distractions are independent of each

Understanding the Uncanny: Both Atypical Features and Category Ambiguity Provoke Aversion toward Humanlike Robots.

Science.gov (United States)

Strait, Megan K; Floerke, Victoria A; Ju, Wendy; Maddox, Keith; Remedios, Jessica D; Jung, Malte F; Urry, Heather L

2017-01-01

Robots intended for social contexts are often designed with explicit humanlike attributes in order to facilitate their reception by (and communication with) people. However, observation of an "uncanny valley"-a phenomenon in which highly humanlike entities provoke aversion in human observers-has lead some to caution against this practice. Both of these contrasting perspectives on the anthropomorphic design of social robots find some support in empirical investigations to date. Yet, owing to outstanding empirical limitations and theoretical disputes, the uncanny valley and its implications for human-robot interaction remains poorly understood. We thus explored the relationship between human similarity and people's aversion toward humanlike robots via manipulation of the agents' appearances. To that end, we employed a picture-viewing task ( N agents = 60) to conduct an experimental test ( N participants = 72) of the uncanny valley's existence and the visual features that cause certain humanlike robots to be unnerving. Across the levels of human similarity, we further manipulated agent appearance on two dimensions, typicality (prototypic, atypical, and ambiguous) and agent identity (robot, person), and measured participants' aversion using both subjective and behavioral indices. Our findings were as follows: (1) Further substantiating its existence, the data show a clear and consistent uncanny valley in the current design space of humanoid robots. (2) Both category ambiguity, and more so, atypicalities provoke aversive responding, thus shedding light on the visual factors that drive people's discomfort. (3) Use of the Negative Attitudes toward Robots Scale did not reveal any significant relationships between people's pre-existing attitudes toward humanlike robots and their aversive responding-suggesting positive exposure and/or additional experience with robots is unlikely to affect the occurrence of an uncanny valley effect in humanoid robotics. This work furthers

Economic assessment of flood forecasts for a risk-averse decision-maker

Science.gov (United States)

Matte, Simon; Boucher, Marie-Amélie; Boucher, Vincent; Fortier-Filion, Thomas-Charles

2017-04-01

A large effort has been made over the past 10 years to promote the operational use of probabilistic or ensemble streamflow forecasts. It has also been suggested in past studies that ensemble forecasts might possess a greater economic value than deterministic forecasts. However, the vast majority of recent hydro-economic literature is based on the cost-loss ratio framework, which might be appealing for its simplicity and intuitiveness. One important drawback of the cost-loss ratio is that it implicitly assumes a risk-neutral decision maker. By definition, a risk-neutral individual is indifferent to forecasts' sharpness: as long as forecasts agree with observations on average, the risk-neutral individual is satisfied. A risk-averse individual, however, is sensitive to the level of precision (sharpness) of forecasts. This person is willing to pay to increase his or her certainty about future events. In fact, this is how insurance companies operate: the probability of seeing one's house burn down is relatively low, so the expected cost related to such event is also low. However, people are willing to buy insurance to avoid the risk, however small, of loosing everything. Similarly, in a context where people's safety and property is at stake, the typical decision maker is more risk-averse than risk-neutral. Consequently, the cost-loss ratio is not the most appropriate tool to assess the economic value of flood forecasts. This presentation describes a more realistic framework for assessing the economic value of such forecasts for flood mitigation purposes. Borrowing from economics, the Constant Absolute Risk Aversion utility function (CARA) is the central tool of this new framework. Utility functions allow explicitly accounting for the level of risk aversion of the decision maker and fully exploiting the information related to ensemble forecasts' uncertainty. Three concurrent ensemble streamflow forecasting systems are compared in terms of quality (comparison with

Brain-derived neurotrophic factor into adult neocortex strengthens a taste aversion memory.

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Martínez-Moreno, Araceli; Rodríguez-Durán, Luis F; Escobar, Martha L

2016-01-15

Nowadays, it is known that brain derived neurotrophic-factor (BDNF) is a protein critically involved in regulating long-term memory related mechanisms. Previous studies from our group in the insular cortex (IC), a brain structure of the temporal lobe implicated in acquisition, consolidation and retention of conditioned taste aversion (CTA), demonstrated that BDNF is essential for CTA consolidation. Recent studies show that BDNF-TrkB signaling is able to mediate the enhancement of memory. However, whether BDNF into neocortex is able to enhance aversive memories remains unexplored. In the present work, we administrated BDNF in a concentration capable of inducing in vivo neocortical LTP, into the IC immediately after CTA acquisition in two different conditions: a "strong-CTA" induced by 0.2M lithium chloride i.p. as unconditioned stimulus, and a "weak-CTA" induced by 0.1M lithium chloride i.p. Our results show that infusion of BDNF into the IC converts a weak CTA into a strong one, in a TrkB receptor-dependent manner. The present data suggest that BDNF into the adult insular cortex is sufficient to increase an aversive memory-trace. Copyright © 2015 Elsevier B.V. All rights reserved.

Response to palatability after area postrema lesions: a result of learned aversions.

Science.gov (United States)

Tomoyasu, N; Kenney, N J

1989-11-01

The role of palatability, novelty, and food aversion in determining changes of food choice after ablation of the area postrema and caudal-medial aspect of the nucleus of the solitary tract (AP/cmNTS) is examined through a series of studies utilizing 24-h, two-food choice tests. On test days, the food that the animal has ingested since the time of lesioning or sham surgery is presented along with a novel food that varies in palatability. The results indicate that postlesion diet history is the major determinant of food choice by lesioned rats. Lesioned rats consistently take less of their familiar postlesion food than diet-matched controls, suggesting that the lesioned rats have developed an aversion to that food. Over-ingestion of the novel food may occur, but this outcome is not reliable. No indication that the animals' response to food palatability is affected by AP/cmNTS ablation was found. Learned aversion to a food ingested after AP/cmNTS ablation may account not only for changes of food preference after the lesion but also may be involved in the hypophagia and weight loss resulting from the ablation.

Risk-Averse Suppliers’ Optimal Pricing Strategies in a Two-Stage Supply Chain

Directory of Open Access Journals (Sweden)

Rui Shen

2013-01-01

Full Text Available Risk-averse suppliers’ optimal pricing strategies in two-stage supply chains under competitive environment are discussed. The suppliers in this paper focus more on losses as compared to profits, and they care their long-term relationship with their customers. We introduce for the suppliers a loss function, which covers both current loss and future loss. The optimal wholesale price is solved under situations of risk neutral, risk averse, and a combination of minimizing loss and controlling risk, respectively. Besides, some properties of and relations among these optimal wholesale prices are given as well. A numerical example is given to illustrate the performance of the proposed method.

Modeling OPEC behavior: theories of risk aversion for oil producer decisions

International Nuclear Information System (INIS)

Reynolds, D.B.

1999-01-01

Theories of OPEC such as price leadership, cartel, or game theoretic models suggest an incentive for OPEC members to expand their production capacity well above current levels in order to maximize revenues. Yet individual OPEC members consistently explore for and develop oil fields at a level well below their potential. The cause of low oil exploration and development efforts among OPEC members, and even some non-OPEC members, may have to do with risk aversion. This paper describes an alternative theory for OPEC behavior based on risk aversion using a two piece non-Neumann-Morgenstern utility function similar to Fishburn and Koehenberger (1979, Decision Science 10, 503-518), and Friedman and Savage (1948, Journal of political Economy 56). The model shows possible low oil production behavior. (author)

Intrahousehold Allocation of Nutrients in Rural India: Are Boys Favored? Do Parents Exhibit Inequality Aversion?

OpenAIRE

Behrman, Jere R

1988-01-01

This paper develops a multinutrient input, multihealth related outcome model of intrahousehold nutrient allocation that permits identification of gender preferences and equity-productivity tradeoffs. Estimates for rural South India suggest that parents display male preference during the lean season, particularly in lower-caste households. Parents also exhibit inequality aversion so pure investment models may be misleading, though such inequality aversion is less in the lean season than estima...

Assessing appetitive, aversive, and negative ethanol-mediated reinforcement through an immature rat model.

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Pautassi, Ricardo M; Nizhnikov, Michael E; Spear, Norman E

2009-06-01

The motivational effects of drugs play a key role during the transition from casual use to abuse and dependence. Ethanol reinforcement has been successfully studied through Pavlovian and operant conditioning in adult rats and mice genetically selected for their ready acceptance of ethanol. Another model for studying ethanol reinforcement is the immature (preweanling) rat, which consumes ethanol and exhibits the capacity to process tactile, odor and taste cues and transfer information between different sensorial modalities. This review describes the motivational effects of ethanol in preweanling, heterogeneous non-selected rats. Preweanlings exhibit ethanol-mediated conditioned taste avoidance and conditioned place aversion. Ethanol's appetitive effects, however, are evident when using first- and second-order conditioning and operant procedures. Ethanol also devalues the motivational representation of aversive stimuli, suggesting early negative reinforcement. It seems that preweanlings are highly sensitive not only to the aversive motivational effects of ethanol but also to its positive and negative (anti-anxiety) reinforcement potential. The review underscores the advantages of using a developing rat to evaluate alcohol's motivational effects.

Optimal fuel-mix in CHP plants under a stochastic permit price. Risk-neutrality versus risk-aversion

International Nuclear Information System (INIS)

Lappi, Pauli; Ollikka, Kimmo; Ollikainen, Markku

2010-01-01

This paper studies the optimal fuel-mix of a CHP producer under emission permit price risk. The producer's multi-fuel plant uses two CO 2 -intensive fuels and one clean fuel. Using a mean-variance framework we develop three models. The models are divided into spot-models (risk neutral and risk averse cases) and a forward-model (risk averse case). We derive the effects of price risk on optimal fuel use. An increase in price risk can in fact increase the use of CO 2 -intensive fuel in the spot-model. In the forward-model, the production and financial decisions are separate. We also evaluate the risk-bearing behavior of seven Finnish CHP producers. We found that risk-neutrality describes behavior better than risk-aversion. (author)

Predicting Cancer-Prevention Behavior: Disentangling the Effects of Risk Aversion and Risk Perceptions.

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Riddel, Mary; Hales, David

2018-05-16

Experimental and survey research spanning the last two decades concludes that people who are more risk tolerant are more likely to engage in risky health activities such as smoking and heavy alcohol consumption, and are more likely to be obese. Subjective perceptions of the risk associated with different activities have also been found to be associated with health behaviors. While there are numerous studies that link risk perceptions with risky behavior, it is notable that none of these controls for risk aversion. Similarly, studies that control for risk aversion fail to control for risk misperceptions. We use a survey of 474 men and women to investigate the influence of risk aversion, risk misperceptions, and cognitive ability on the choice to engage in behaviors that either increase or mitigate cancer risk. We measure optimism in two dimensions: baseline optimists are those who inaccurately believe their cancer risk to be below its expert-assessed level, while control optimists are those who believe they can reduce their risk of cancer (by changing their lifestyle choices) to a greater extent than is actually the case. Our results indicate that baseline optimism is significantly and negatively correlated with subjects' tendencies to engage in cancer-risk-reducing behaviors, and positively correlated with risky behaviors. Subjects' control misperceptions also appear to play a role in their tendency to engage in risky and prevention behaviors. When controlling for both of these types of risk misperception, risk aversion plays a much smaller role in determining health behaviors than found in past studies. © 2018 Society for Risk Analysis.

Suboptimal nutrient balancing despite dietary choice in glucose-averse German cockroaches, Blattella germanica.

Science.gov (United States)

Jensen, Kim; Schal, Coby; Silverman, Jules

2015-10-01

Insects have evolved fine-tuned gustatory and post-ingestive physiological mechanisms that enable them to self-select an optimal composition of macronutrients. Their ability to forage optimally among multiple food sources and maximize fitness parameters depends on their ability not only to taste and perceive the nutritional value of potential foods but also to avoid deleterious components; the strength of such avoidance should reflect the severity of the perceived hazard. In German cockroaches (Blattella germanica), glucose aversion has evolved in some populations in response to anthropogenic selection with glucose-containing insecticidal baits. In four feeding treatments, we gave newly eclosed glucose-averse female cockroaches free choice to feed from two artificial, nutritionally complementary foods varying in protein and carbohydrate composition, with glucose or fructose as the sole carbohydrate source in either food. After 6days of feeding, we measured diet consumption and the length of basal oocytes as an estimate of sexual maturation. The females did not compromise on their aversion to glucose in order to balance their protein and carbohydrate intake, and experienced lower sexual maturation rates as a consequence. Nutrient specific hunger via feedback mechanisms, and adjustments to gustatory sensitivity thus do not override the deterrence of glucose, likely due to strong selection against ingesting even small amounts of toxin associated with glucose in baits. In the absence of baits, glucose aversion would be expected to incur a fitness cost compared to wild-type individuals due to lower overall food availability but also to larger difficulty in attaining a nutritionally balanced diet. Copyright © 2015 Elsevier Ltd. All rights reserved.

PKMζ maintains drug reward and aversion memory in the basolateral amygdala and extinction memory in the infralimbic cortex.

Science.gov (United States)

He, Ying-Ying; Xue, Yan-Xue; Wang, Ji-Shi; Fang, Qin; Liu, Jian-Feng; Xue, Li-Fen; Lu, Lin

2011-09-01

The intense associative memories that develop between drug-paired contextual cues and rewarding stimuli or the drug withdrawal-associated aversive feeling have been suggested to contribute to the high rate of relapse. Various studies have elucidated the mechanisms underlying the formation and expression of drug-related cue memories, but how this mechanism is maintained is unknown. Protein kinase M ζ (PKMζ) was recently shown to be necessary and sufficient for long-term potentiation maintenance and memory storage. In the present study, we used conditioned place preference (CPP) and aversion (CPA) to examine whether PKMζ maintains both morphine-associated reward memory and morphine withdrawal-associated aversive memory in the basolateral amygdala (BLA). We also investigate the role of PKMζ in the infralimbic cortex in the extinction memory of morphine reward-related cues and morphine withdrawal-related aversive cues. We found that intra-BLA but not central nucleus of the amygdala injection of the selective PKMζ inhibitor ZIP 1 day after CPP and CPA training impaired the expression of CPP and CPA 1 day later, and the effect of ZIP on memory lasted at least 2 weeks. Inhibiting PKMζ activity in the infralimbic cortex, but not prelimbic cortex, disrupted the expression of the extinction memory of CPP and CPA. These results indicate that PKMζ in the BLA is required for the maintenance of associative morphine reward memory and morphine withdrawal-associated aversion memory, and PKMζ in the infralimbic cortex is required for the maintenance of extinction memory of morphine reward-related cues and morphine withdrawal-related aversive cues.

Mechanisms of attention for appetitive and aversive outcomes in Pavlovian conditioning.

Science.gov (United States)

Austin, A J; Duka, T

2010-11-12

Different mechanisms of attention controlling learning have been proposed in appetitive and aversive conditioning. The aim of the present study was to compare attention and learning in a Pavlovian conditioning paradigm using visual stimuli of varying predictive value of either monetary reward (appetitive conditioning; 10p or 50p) or blast of white noise (aversive conditioning; 97 dB or 102 dB). Outcome values were matched across the two conditions with regard to their emotional significance. Sixty-four participants were allocated to one of the four conditions matched for age and gender. All participants underwent a discriminative learning task using pairs of visual stimuli that signalled a 100%, 50%, or 0% probability of receiving an outcome. Learning was measured using a 9-point Likert scale of expectancy of the outcome, while attention using an eyetracker device. Arousal and emotional conditioning were also evaluated. Dwell time was greatest for the full predictor in the noise groups, while in the money groups attention was greatest for the partial predictor over the other two predictors. The progression of learning was the same for both groups. These findings suggest that in aversive conditioning attention is driven by the predictive salience of the stimulus while in appetitive conditioning attention is error-driven, when emotional value of the outcome is comparable. (c) 2010 Elsevier B.V. All rights reserved.

Role of PKA signaling in D2 receptor-expressing neurons in the core of the nucleus accumbens in aversive learning.

Science.gov (United States)

Yamaguchi, Takashi; Goto, Akihiro; Nakahara, Ichiro; Yawata, Satoshi; Hikida, Takatoshi; Matsuda, Michiyuki; Funabiki, Kazuo; Nakanishi, Shigetada

2015-09-08

The nucleus accumbens (NAc) serves as a key neural substrate for aversive learning and consists of two distinct subpopulations of medium-sized spiny neurons (MSNs). The MSNs of the direct pathway (dMSNs) and the indirect pathway (iMSNs) predominantly express dopamine (DA) D1 and D2 receptors, respectively, and are positively and negatively modulated by DA transmitters via Gs- and Gi-coupled cAMP-dependent protein kinase A (PKA) signaling cascades, respectively. In this investigation, we addressed how intracellular PKA signaling is involved in aversive learning in a cell type-specific manner. When the transmission of either dMSNs or iMSNs was unilaterally blocked by pathway-specific expression of transmission-blocking tetanus toxin, infusion of PKA inhibitors into the intact side of the NAc core abolished passive avoidance learning toward an electric shock in the indirect pathway-blocked mice, but not in the direct pathway-blocked mice. We then examined temporal changes in PKA activity in dMSNs and iMSNs in behaving mice by monitoring Förster resonance energy transfer responses of the PKA biosensor with the aid of microendoscopy. PKA activity was increased in iMSNs and decreased in dMSNs in both aversive memory formation and retrieval. Importantly, the increased PKA activity in iMSNs disappeared when aversive memory was prevented by keeping mice in the conditioning apparatus. Furthermore, the increase in PKA activity in iMSNs by aversive stimuli reflected facilitation of aversive memory retention. These results indicate that PKA signaling in iMSNs plays a critical role in both aversive memory formation and retention.

Good luck, bad luck, and ambiguity aversion

OpenAIRE

Briony D. Pulford; Poonam Gill

2014-01-01

We report a series of experiments investigating the influence of feeling lucky or unlucky on people's choice of known-risk or ambiguous options using the traditional Ellsberg Urns decision-making task. We induced a state of feeling lucky or unlucky in subjects by using a rigged wheel-of-fortune game, which just missed either the bankrupt or the jackpot outcome. In the first experiment a large reversal of the usual ambiguity aversion effect was shown, indicating that feeling ...

Inflation Aversion and the Optimal Inflation Tax

OpenAIRE

Gaowang Wang; Heng-fu Zou

2011-01-01

The optimal inflation tax is reexamined in the framework of dynamic second best economy populated by individuals with inflation aversion. A simple formula for the optimal inflation rate is derived. Different from the literature, it is shown that if the marginal excess burden of other distorting taxes approaches zero, Friedman's rule for optimum quantity of money is not optimal, and the optimal inflation tax is negative; if the marginal excess burden of other taxes is nonzero, the optimal infl...

Effects of dose and of partial body ionizing radiation on taste aversion learning in rats with lesions of the area postrema

International Nuclear Information System (INIS)

Rabin, B.M.; Hunt, W.A.; Lee, J.

1984-01-01

The effect of area postrema lesions on the acquisition of a conditioned taste aversion following partial body exposure to ionizing radiation was investigated in rats exposed to head-only irradiation at 100, 200 and 300 rad or to body-only irradiation at 100 and 200 rad. Following head-only irradiation area postrema lesions produced a significant attenuation of the radiation-induced taste aversion at all dose levels, although the rats still showed a significant reduction in sucrose preference. Following body-only exposure, area postrema lesions completely disrupted the acquisition of the conditioned taste aversion. The results are interpreted as indicating that: (a) the acquisition of a conditioned taste aversion following body-only exposure is mediated by the area postrema; and (b) taste aversion learning following radiation exposure to the head-only is mediated by both the area postrema and a mechanism which is independent of the area postrema

Cisplatin-Induced Conditioned Taste Aversion: Attenuation by Dexamethasone but not Zacopride or GR38032F

Science.gov (United States)

1992-01-01

SR2-1 Cisplatin-induced conditioned taste aversion: ateuto by dexamethasone but not zacopride or GR38032F Nm I- Paul C Mele, John R. McDonough, David...to 5-H1’, receptor blockade. 5-HT., receptor antagonists; Zacopridc: GR38032F; Desamethasone: Cisplatin: Taste aversion (conditioned) I. Introductlon...intake) was used as the area known as the chemoreceptor trigger zone (Borri- index of the CTA. son, 1974). Moreover. the findings that rats, ferrets

Individual differences in aversion to ambiguity regarding medical tests and treatments: association with cancer screening cognitions.

Science.gov (United States)

Han, Paul K J; Williams, Andrew E; Haskins, Amy; Gutheil, Caitlin; Lucas, F Lee; Klein, William M P; Mazor, Kathleen M

2014-12-01

Aversion to "ambiguity"-uncertainty about the reliability, credibility, or adequacy of information-about medical tests and treatments is an important psychological response that varies among individuals, but little is known about its nature and extent. The purpose of this study was to examine how individual-level ambiguity aversion relates to important health cognitions related to different cancer screening tests. A survey of 1,074 adults, ages 40 to 70 years, was conducted in four integrated U.S. healthcare systems. The Ambiguity Aversion in Medicine (AA-Med) scale, a measure of individual differences in aversion to ambiguity (AA) about medical tests and treatments, was administered along with measures of several cancer screening-related cognitions: perceived benefits and harms of colonoscopy, mammography, and PSA screening, and ambivalence and future intentions regarding these tests. Multivariable analyses were conducted to assess the associations between AA-Med scores and cancer screening cognitions. Individual-level AA as assessed by the AA-Med scale was significantly associated (P ambiguity. Individual-level AA constitutes a measurable, wide-ranging cognitive bias against medical intervention, and more research is needed to elucidate its mechanisms and effects. ©2014 American Association for Cancer Research.

Risk-averse formulations and methods for a virtual power plant

KAUST Repository

Lima, Ricardo M.; Conejo, Antonio J.; Langodan, Sabique; Hoteit, Ibrahim; Knio, Omar M.

2017-01-01

In this paper we address the optimal operation of a virtual power plant using stochastic programming. We consider one risk-neutral and two risk-averse formulations that rely on the conditional value at risk. To handle large-scale problems, we implement two decomposition methods with variants using single- and multiple-cuts. We propose the utilization of wind ensembles obtained from the European Centre for Medium Range Weather Forecasts (ECMWF) to quantify the uncertainty of the wind forecast. We present detailed results relative to the computational performance of the risk-averse formulations, the decomposition methods, and risk management and sensitivities analysis as a function of the number of scenarios and risk parameters. The implementation of the two decomposition methods relies on the parallel solution of subproblems, which turns out to be paramount for computational efficiency. The results show that one of the two decomposition methods is the most efficient.

Risk-averse formulations and methods for a virtual power plant

KAUST Repository

Lima, Ricardo M.

2017-12-15

In this paper we address the optimal operation of a virtual power plant using stochastic programming. We consider one risk-neutral and two risk-averse formulations that rely on the conditional value at risk. To handle large-scale problems, we implement two decomposition methods with variants using single- and multiple-cuts. We propose the utilization of wind ensembles obtained from the European Centre for Medium Range Weather Forecasts (ECMWF) to quantify the uncertainty of the wind forecast. We present detailed results relative to the computational performance of the risk-averse formulations, the decomposition methods, and risk management and sensitivities analysis as a function of the number of scenarios and risk parameters. The implementation of the two decomposition methods relies on the parallel solution of subproblems, which turns out to be paramount for computational efficiency. The results show that one of the two decomposition methods is the most efficient.

The Effect of Swimming Experience on Acquisition and Retention of Swimming-Based Taste Aversion Learning in Rats

Science.gov (United States)

Masaki, Takahisa; Nakajima, Sadahiko

2010-01-01

Swimming endows rats with an aversion to a taste solution consumed before swimming. The present study explored whether the experience of swimming before or after the taste-swimming trials interferes with swimming-based taste aversion learning. Experiment 1 demonstrated that a single preexposure to 20 min of swimming was as effective as four or…

Differential involvement of cortical muscarinic and NMDA receptors in short- and long-term taste aversion memory.

Science.gov (United States)

Ferreira, G; Gutiérrez, R; De La Cruz, V; Bermúdez-Rattoni, F

2002-09-01

In conditioned taste aversion, an animal avoids a taste previously associated with toxic effects, and this aversive memory formation requires an intact insular cortex. In this paper, we investigated the possible differential involvement of cholinergic and glutamatergic receptors in the insular cortex in short-term memory (STM) and long-term memory (LTM) of taste aversion in rats. Taste aversion was induced by intraperitoneal administration of lithium chloride (a malaise-inducing drug) 15 min after experience with an unfamiliar taste. In order to test STM and LTM of taste aversion, taste stimulus was again presented 4 h and 72 h after lithium injection, respectively. During the acquisition, microinjection of the muscarinic antagonist, scopolamine, in the insular cortex before, but not after, the presentation of the new taste, abolished STM as well as LTM. Blockade of the NMDA receptor, in the insular cortex, by AP5 before, but not after, the presentation of the taste stimulus, impaired LTM but left STM intact. Moreover, when injected 1 h after malaise induction (i.e., during taste-illness association), AP5 disrupted both STM and LTM. These results suggest that activation of muscarinic receptors in the insular cortex is involved in the acquisition of taste memory, whereas NMDA receptors participate in taste memory consolidation. These data demonstrate that different neurochemical mechanisms subserve different memory phases. NMDA receptors are also probably involved in processing the visceral input, thus allowing subsequent taste-illness association. This indicates that in the same cortical area the same neurotransmitter system can be involved in distinct processes: taste memory consolidation vs. taste-illness association.

Studies on the role of central histamine in the acquisition of a radiation-induced conditioned taste aversion

International Nuclear Information System (INIS)

Rabin, B.M.; Hunt, W.A.; Lee, J.

1982-01-01

The experiments described in this report were designed to test two hypotheses about how exposure to low-level radiation can affect the behavior of an organism: first, tht radiation effects on behavior are mediated by a radiation-induced release of histamine; and second, that this radiation-induced histamine release can exert relatively direct effects on the central nervous system. The results of the first experiment showed that microinjection of histamine directly into the fourth ventricle of rats produced a taste aversion to a novel sucrose solution. Pretreating rats with intraventricular H 1 or H 2 blockers was not effective in preventing the acquisition of the radiation-induced aversion, although the H 1 blocker did prevent the acquisition of a histamine-induced taste aversion. It also was not possible to establish a cross-tolerance between centrally administered histamine and radiation. The results are interpreted as not supporting the hypothesis that a radiation-induced release of central histamine mediates the acquisition of a conditioned taste aversion following exposure to low-level radiation

Quantifying uncertainty in pest risk maps and assessments: adopting a risk-averse decision maker’s perspective

Directory of Open Access Journals (Sweden)

Denys Yemshanov

2013-09-01

Full Text Available Pest risk maps are important decision support tools when devising strategies to minimize introductions of invasive organisms and mitigate their impacts. When possible management responses to an invader include costly or socially sensitive activities, decision-makers tend to follow a more certain (i.e., risk-averse course of action. We presented a new mapping technique that assesses pest invasion risk from the perspective of a risk-averse decision maker.We demonstrated the method by evaluating the likelihood that an invasive forest pest will be transported to one of the U.S. states or Canadian provinces in infested firewood by visitors to U.S. federal campgrounds. We tested the impact of the risk aversion assumption using distributions of plausible pest arrival scenarios generated with a geographically explicit model developed from data documenting camper travel across the study area. Next, we prioritized regions of high and low pest arrival risk via application of two stochastic ordering techniques that employed, respectively, first- and second-degree stochastic dominance rules, the latter of which incorporated the notion of risk aversion. We then identified regions in the study area where the pest risk value changed considerably after incorporating risk aversion.While both methods identified similar areas of highest and lowest risk, they differed in how they demarcated moderate-risk areas. In general, the second-order stochastic dominance method assigned lower risk rankings to moderate-risk areas. Overall, this new method offers a better strategy to deal with the uncertainty typically associated with risk assessments and provides a tractable way to incorporate decision-making preferences into final risk estimates, and thus helps to better align these estimates with particular decision-making scenarios about a pest organism of concern. Incorporation of risk aversion also helps prioritize the set of locations to target for inspections and

Learning context modulates aversive taste strength in honey bees.

Science.gov (United States)

de Brito Sanchez, Maria Gabriela; Serre, Marion; Avarguès-Weber, Aurore; Dyer, Adrian G; Giurfa, Martin

2015-03-01

The capacity of honey bees (Apis mellifera) to detect bitter substances is controversial because they ingest without reluctance different kinds of bitter solutions in the laboratory, whereas free-flying bees avoid them in visual discrimination tasks. Here, we asked whether the gustatory perception of bees changes with the behavioral context so that tastes that are less effective as negative reinforcements in a given context become more effective in a different context. We trained bees to discriminate an odorant paired with 1 mol l(-1) sucrose solution from another odorant paired with either distilled water, 3 mol l(-1) NaCl or 60 mmol l(-1) quinine. Training was either Pavlovian [olfactory conditioning of the proboscis extension reflex (PER) in harnessed bees], or mainly operant (olfactory conditioning of free-walking bees in a Y-maze). PER-trained and maze-trained bees were subsequently tested both in their original context and in the alternative context. Whereas PER-trained bees transferred their choice to the Y-maze situation, Y-maze-trained bees did not respond with a PER to odors when subsequently harnessed. In both conditioning protocols, NaCl and distilled water were the strongest and the weakest aversive reinforcement, respectively. A significant variation was found for quinine, which had an intermediate aversive effect in PER conditioning but a more powerful effect in the Y-maze, similar to that of NaCl. These results thus show that the aversive strength of quinine varies with the learning context, and reveal the plasticity of the bee's gustatory system. We discuss the experimental constraints of both learning contexts and focus on stress as a key modulator of taste in the honey bee. Further explorations of bee taste are proposed to understand the physiology of taste modulation in bees. © 2015. Published by The Company of Biologists Ltd.

Correlations of self-esteem and intolerance of ambiguity with risk aversion.

Science.gov (United States)

Johanson, J C

2000-10-01

The current paper reports for 80 undergraduates that risk aversion is greater among those with lower self-esteem scores on Rosenberg's Self-esteem Scale and those with higher scores on Budner's Intolerance of Ambiguity Scale.

Optimal fuel-mix in CHP plants under a stochastic permit price. Risk-neutrality versus risk-aversion

Energy Technology Data Exchange (ETDEWEB)

Lappi, Pauli; Ollikka, Kimmo; Ollikainen, Markku [Department of Economics and Management, P.O. Box 27, University of Helsinki, FIN-00014 Helsinki (Finland)

2010-02-15

This paper studies the optimal fuel-mix of a CHP producer under emission permit price risk. The producer's multi-fuel plant uses two CO{sub 2}-intensive fuels and one clean fuel. Using a mean-variance framework we develop three models. The models are divided into spot-models (risk neutral and risk averse cases) and a forward-model (risk averse case). We derive the effects of price risk on optimal fuel use. An increase in price risk can in fact increase the use of CO{sub 2}-intensive fuel in the spot-model. In the forward-model, the production and financial decisions are separate. We also evaluate the risk-bearing behavior of seven Finnish CHP producers. We found that risk-neutrality describes behavior better than risk-aversion. (author)

Optimal fuel-mix in CHP plants under a stochastic permit price: Risk-neutrality versus risk-aversion

Energy Technology Data Exchange (ETDEWEB)

Lappi, Pauli, E-mail: pauli.lappi@helsinki.f [Department of Economics and Management, P.O. Box 27, University of Helsinki, FIN-00014 Helsinki (Finland); Ollikka, Kimmo, E-mail: kimmo.ollikka@helsinki.f [Department of Economics and Management, P.O. Box 27, University of Helsinki, FIN-00014 Helsinki (Finland); Ollikainen, Markku, E-mail: markku.ollikainen@helsinki.f [Department of Economics and Management, P.O. Box 27, University of Helsinki, FIN-00014 Helsinki (Finland)

2010-02-15

This paper studies the optimal fuel-mix of a CHP producer under emission permit price risk. The producer's multi-fuel plant uses two CO{sub 2}-intensive fuels and one clean fuel. Using a mean-variance framework we develop three models. The models are divided into spot-models (risk neutral and risk averse cases) and a forward-model (risk averse case). We derive the effects of price risk on optimal fuel use. An increase in price risk can in fact increase the use of CO{sub 2}-intensive fuel in the spot-model. In the forward-model, the production and financial decisions are separate. We also evaluate the risk-bearing behavior of seven Finnish CHP producers. We found that risk-neutrality describes behavior better than risk-aversion.

On the genetics of loss aversion: An interaction effect of BDNF Val66Met and DRD2/ANKK1 Taq1a.

Science.gov (United States)

Voigt, Gesine; Montag, Christian; Markett, Sebastian; Reuter, Martin

2015-12-01

Loss aversion is the tendency to overweight losses compared with gains in decision situations. Several studies have investigated the neurobiological background of this phenomenon and it was found that activation in the mesolimbic-mesocortical dopamine system during a gambling decision correlates with loss aversion. In a behavioral experiment with N = 143 subjects, the present study investigates the influence of 2 functional single-nucleotide polymorphisms on the BDNF gene (BDNF Val66Met polymorphism) and ANKK1 gene (DRD2 Taq1a/ANKK1 polymorphism), that are known to affect the dopamine system, on loss aversion. Additionally, associations of alexithymia, a personality construct describing the disability to consciously experience emotions in the self, with loss aversion and with the mentioned polymorphisms were assessed using the TAS-20 questionnaire, to replicate associations that have been reported before. Results revealed a significant interaction effect of the 2 polymorphisms on loss aversion. Carriers of the genetic constellation 66Met+/A1+ had the lowest loss aversion scores, compared with all other allelic groups. According to the literature this allelic configuration is characterized by a relatively low D2/3 receptor binding in the striatum and an impaired activity-dependent secretion of BDNF. This is the first study showing that loss aversion is related to naturally occurring differences in dopamine function. (c) 2015 APA, all rights reserved).

Algorithm aversion: people erroneously avoid algorithms after seeing them err.

Science.gov (United States)

Dietvorst, Berkeley J; Simmons, Joseph P; Massey, Cade

2015-02-01

Research shows that evidence-based algorithms more accurately predict the future than do human forecasters. Yet when forecasters are deciding whether to use a human forecaster or a statistical algorithm, they often choose the human forecaster. This phenomenon, which we call algorithm aversion, is costly, and it is important to understand its causes. We show that people are especially averse to algorithmic forecasters after seeing them perform, even when they see them outperform a human forecaster. This is because people more quickly lose confidence in algorithmic than human forecasters after seeing them make the same mistake. In 5 studies, participants either saw an algorithm make forecasts, a human make forecasts, both, or neither. They then decided whether to tie their incentives to the future predictions of the algorithm or the human. Participants who saw the algorithm perform were less confident in it, and less likely to choose it over an inferior human forecaster. This was true even among those who saw the algorithm outperform the human.

Forward conditioning with wheel running causes place aversion in rats.

Science.gov (United States)

Masaki, Takahisa; Nakajima, Sadahiko

2008-09-01

Backward pairings of a distinctive chamber as a conditioned stimulus and wheel running as an unconditioned stimulus (i.e., running-then-chamber) can produce a conditioned place preference in rats. The present study explored whether a forward conditioning procedure with these stimuli (i.e., chamber-then-running) would yield place preference or aversion. Confinement of a rat in one of two distinctive chambers was followed by a 20- or 60-min running opportunity, but confinement in the other was not. After four repetitions of this treatment (i.e., differential conditioning), a choice preference test was given in which the rat had free access to both chambers. This choice test showed that the rats given 60-min running opportunities spent less time in the running-paired chamber than in the unpaired chamber. Namely, a 60-min running opportunity after confinement in a distinctive chamber caused conditioned aversion to that chamber after four paired trials. This result was discussed with regard to the opponent-process theory of motivation.

Does ambiguity aversion influence the framing effect during decision making?

Science.gov (United States)

Osmont, Anaïs; Cassotti, Mathieu; Agogué, Marine; Houdé, Olivier; Moutier, Sylvain

2015-04-01

Decision-makers present a systematic tendency to avoid ambiguous options for which the level of risk is unknown. This ambiguity aversion is one of the most striking decision-making biases. Given that human choices strongly depend on the options' presentation, the purpose of the present study was to examine whether ambiguity aversion influences the framing effect during decision making. We designed a new financial decision-making task involving the manipulation of both frame and uncertainty levels. Thirty-seven participants had to choose between a sure option and a gamble depicting either clear or ambiguous probabilities. The results revealed a clear preference for the sure option in the ambiguity condition regardless of frame. However, participants presented a framing effect in both the risk and ambiguity conditions. Indeed, the framing effect was bidirectional in the risk condition and unidirectional in the ambiguity condition given that it did not involve preference reversal but only a more extreme choice tendency.

Effects of kappa opioid receptors on conditioned place aversion and social interaction in males and females

Science.gov (United States)

Robles, Cindee F.; McMackin, Marissa Z.; Campi, Katharine L.; Doig, Ian E.; Takahashi, Elizabeth Y.; Pride, Michael; Trainor, Brian C.

2014-01-01

The effects of kappa opioid receptors (KOR) on motivated behavior are well established based on studies in male rodents, but relatively little is known about the effects of KOR in females. We examined the effects of KOR activation on conditioned place aversion and social interaction in the California mouse (Peromyscus californicus). Important differences were observed in long-term (place aversion) and short-term (social interaction) effects. Females but not males treated with a 2.5mg/kg dose of U50,488 formed a place aversion, whereas males but not females formed a place aversion at the 10 mg/kg dose. In contrast the short term effects of different doses of U50,488 on social interaction behavior were similar in males and females. Acute injection with 10 mg/kg of U50,488 (but not lower doses) reduced social interaction behavior in both males and females. The effects of U50,488 on phosphorylated extracellular signal regulated kinase (pERK) and p38 MAP kinase were cell type and region specific. Higher doses of U50,488 increased the number of pERK neurons in the ventrolateral bed nucleus of the stria terminals in males but not females, a nucleus implicated in male aggressive behavior. In contrast, both males and females treated with U50,488 had more activated p38 cells in the nucleus accumbens shell. Unexpectedly, cells expressing activated p38 co-expressed Iba-1, a widely used microglia marker. In summary we found strong sex differences in the effects of U50,488 on place aversion whereas the acute effects on U50,488 induced similar behavioral effects in males and females. PMID:24445073

Aversive Learning and Appetitive Motivation Toggle Feed-Forward Inhibition in the Drosophila Mushroom Body.

Science.gov (United States)

Perisse, Emmanuel; Owald, David; Barnstedt, Oliver; Talbot, Clifford B; Huetteroth, Wolf; Waddell, Scott

2016-06-01

In Drosophila, negatively reinforcing dopaminergic neurons also provide the inhibitory control of satiety over appetitive memory expression. Here we show that aversive learning causes a persistent depression of the conditioned odor drive to two downstream feed-forward inhibitory GABAergic interneurons of the mushroom body, called MVP2, or mushroom body output neuron (MBON)-γ1pedc>α/β. However, MVP2 neuron output is only essential for expression of short-term aversive memory. Stimulating MVP2 neurons preferentially inhibits the odor-evoked activity of avoidance-directing MBONs and odor-driven avoidance behavior, whereas their inhibition enhances odor avoidance. In contrast, odor-evoked activity of MVP2 neurons is elevated in hungry flies, and their feed-forward inhibition is required for expression of appetitive memory at all times. Moreover, imposing MVP2 activity promotes inappropriate appetitive memory expression in food-satiated flies. Aversive learning and appetitive motivation therefore toggle alternate modes of a common feed-forward inhibitory MVP2 pathway to promote conditioned odor avoidance or approach. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Acute infusion of brain-derived neurotrophic factor in the insular cortex promotes conditioned taste aversion extinction.

Science.gov (United States)

Rodríguez-Serrano, Luis M; Ramírez-León, Betsabee; Rodríguez-Durán, Luis F; Escobar, Martha L

2014-12-01

Brain-derived neurotrophic factor (BDNF) has emerged as one of the most potent molecular mediators not only for synaptic plasticity, but also for the behavioral organism-environment interactions. Our previous studies in the insular cortex (IC), a neocortical region that has been related with acquisition and retention of conditioned taste aversion (CTA), have demonstrated that intracortical microinfusion of BDNF induces a lasting potentiation of synaptic efficacy in the basolateral amygdaloid nucleus (Bla)-IC projection and enhances the retention of CTA memory of adult rats in vivo. The aim of the present study was to analyze whether acute BDNF-infusion in the IC modifies the extinction of CTA. Accordingly, animals were trained in the CTA task and received bilateral IC microinfusions of BDNF before extinction training. Our results showed that taste aversion was significantly reduced in BDNF rats from the first extinction trial. Additionally, we found that the effect of BDNF on taste aversion did not require extinction training. Finally we showed that the BDNF effect does not degrade the original taste aversion memory trace. These results emphasize that BDNF activity underlies memory extinction in neocortical areas and support the idea that BDNF is a key regulator and mediator of long-term synaptic modifications. Copyright © 2014 Elsevier Inc. All rights reserved.

Dopamine Regulates Aversive Contextual Learning and Associated In Vivo Synaptic Plasticity in the Hippocampus

Directory of Open Access Journals (Sweden)

John I. Broussard

2016-03-01

Full Text Available Dopamine release during reward-driven behaviors influences synaptic plasticity. However, dopamine innervation and release in the hippocampus and its role during aversive behaviors are controversial. Here, we show that in vivo hippocampal synaptic plasticity in the CA3-CA1 circuit underlies contextual learning during inhibitory avoidance (IA training. Immunohistochemistry and molecular techniques verified sparse dopaminergic innervation of the hippocampus from the midbrain. The long-term synaptic potentiation (LTP underlying the learning of IA was assessed with a D1-like dopamine receptor agonist or antagonist in ex vivo hippocampal slices and in vivo in freely moving mice. Inhibition of D1-like dopamine receptors impaired memory of the IA task and prevented the training-induced enhancement of both ex vivo and in vivo LTP induction. The results indicate that dopamine-receptor signaling during an aversive contextual task regulates aversive memory retention and regulates associated synaptic mechanisms in the hippocampus that likely underlie learning.

Sudden-Death Aversion: Avoiding Superior Options Because They Feel Riskier.

Science.gov (United States)

Walker, Jesse; Risen, Jane L; Gilovich, Thomas; Thaler, Richard

2018-01-15

We present evidence of sudden-death aversion (SDA)-the tendency to avoid "fast" strategies that provide a greater chance of success, but include the possibility of immediate defeat, in favor of "slow" strategies that reduce the possibility of losing quickly, but have lower odds of ultimate success. Using a combination of archival analyses and controlled experiments, we explore the psychology behind SDA. First, we provide evidence for SDA and its cost to decision makers by tabulating how often NFL teams send games into overtime by kicking an extra point rather than going for the 2-point conversion (Study 1) and how often NBA teams attempt potentially game-tying 2-point shots rather than potentially game-winning 3-pointers (Study 2). To confirm that SDA is not limited to sports, we demonstrate SDA in a military scenario (Study 3). We then explore two mechanisms that contribute to SDA: myopic loss aversion and concerns about "tempting fate." Studies 4 and 5 show that SDA is due, in part, to myopic loss aversion, such that decision makers narrow the decision frame, paying attention to the prospect of immediate loss with the "fast" strategy, but not the downstream consequences of the "slow" strategy. Study 6 finds that people are more pessimistic about a risky strategy that needn't be pursued (opting for sudden death) than the same strategy that must be pursued. We end by discussing how these twin mechanisms lead to differential expectations of blame from the self and others, and how SDA influences decisions in several different walks of life. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Discrete Serotonin Systems Mediate Memory Enhancement and Escape Latencies after Unpredicted Aversive Experience in Drosophila Place Memory

Directory of Open Access Journals (Sweden)

Divya Sitaraman

2017-12-01

Full Text Available Feedback mechanisms in operant learning are critical for animals to increase reward or reduce punishment. However, not all conditions have a behavior that can readily resolve an event. Animals must then try out different behaviors to better their situation through outcome learning. This form of learning allows for novel solutions and with positive experience can lead to unexpected behavioral routines. Learned helplessness, as a type of outcome learning, manifests in part as increases in escape latency in the face of repeated unpredicted shocks. Little is known about the mechanisms of outcome learning. When fruit fly Drosophilamelanogaster are exposed to unpredicted high temperatures in a place learning paradigm, flies both increase escape latencies and have a higher memory when given control of a place/temperature contingency. Here we describe discrete serotonin neuronal circuits that mediate aversive reinforcement, escape latencies, and memory levels after place learning in the presence and absence of unexpected aversive events. The results show that two features of learned helplessness depend on the same modulatory system as aversive reinforcement. Moreover, changes in aversive reinforcement and escape latency depend on local neural circuit modulation, while memory enhancement requires larger modulation of multiple behavioral control circuits.

Induction of latent memory for conditioned food aversion and its transformation into "active" state depend on translation and transcription processes.

Science.gov (United States)

Solntseva, S V; Nikitin, V P

2014-05-01

Mechanisms of induction and retrieval of latent (hidden) memory for conditioned food aversion were investigated in snails. After initial training (single combination of a food stimulus with electric shock), aversive reactions to presentation of the conditioned food stimulus were not revealed. Repeated presentation of the stimuli in 12 days after the first combination was followed by the appearance of aversive food reactions that persisted for at least 14 days. Injections of inhibitors of protein (cycloheximide) or RNA (α-amanitin) synthesis immediately after the first or second combined presentation of the stimuli disturbed skill performance. We hypothesized that single combination of food and reinforcing stimuli led to translation- and transcription-dependent induction of latent conditioned food aversion memory. Transformation of this memory into an active state after repeated presentation of the stimulus combination also depends on the synthesis of new proteins and RNA.

Reward salience and risk aversion underlie differential ACC activity in substance dependence.

Science.gov (United States)

Alexander, William H; Fukunaga, Rena; Finn, Peter; Brown, Joshua W

2015-01-01

The medial prefrontal cortex, especially the dorsal anterior cingulate cortex (ACC), has long been implicated in cognitive control and error processing. Although the association between ACC and behavior has been established, it is less clear how ACC contributes to dysfunctional behavior such as substance dependence. Evidence from neuroimaging studies investigating ACC function in substance users is mixed, with some studies showing disengagement of ACC in substance dependent individuals (SDs), while others show increased ACC activity related to substance use. In this study, we investigate ACC function in SDs and healthy individuals performing a change signal task for monetary rewards. Using a priori predictions derived from a recent computational model of ACC, we find that ACC activity differs between SDs and controls in factors related to reward salience and risk aversion between SDs and healthy individuals. Quantitative fits of a computational model to fMRI data reveal significant differences in best fit parameters for reward salience and risk preferences. Specifically, the ACC in SDs shows greater risk aversion, defined as concavity in the utility function, and greater attention to rewards relative to reward omission. Furthermore, across participants risk aversion and reward salience are positively correlated. The results clarify the role that ACC plays in both the reduced sensitivity to omitted rewards and greater reward valuation in SDs. Clinical implications of applying computational modeling in psychiatry are also discussed.

Excitation of lateral habenula neurons as a neural mechanism underlying ethanol‐induced conditioned taste aversion

Science.gov (United States)

Keefe, Kristen A.; Taha, Sharif A.

2016-01-01

Key points The lateral habenula (LHb) has been implicated in regulation of drug‐seeking behaviours through aversion‐mediated learning.In this study, we recorded neuronal activity in the LHb of rats during an operant task before and after ethanol‐induced conditioned taste aversion (CTA) to saccharin.Ethanol‐induced CTA caused significantly higher baseline firing rates in LHb neurons, as well as elevated firing rates in response to cue presentation, lever press and saccharin taste.In a separate cohort of rats, we found that bilateral LHb lesions blocked ethanol‐induced CTA.Our results strongly suggest that excitation of LHb neurons is required for ethanol‐induced CTA, and point towards a mechanism through which LHb firing may regulate voluntary ethanol consumption. Abstract Ethanol, like other drugs of abuse, has both rewarding and aversive properties. Previous work suggests that sensitivity to ethanol's aversive effects negatively modulates voluntary alcohol intake and thus may be important in vulnerability to developing alcohol use disorders. We previously found that rats with lesions of the lateral habenula (LHb), which is implicated in aversion‐mediated learning, show accelerated escalation of voluntary ethanol consumption. To understand neural encoding in the LHb contributing to ethanol‐induced aversion, we recorded neural firing in the LHb of freely behaving, water‐deprived rats before and after an ethanol‐induced (1.5 g kg−1 20% ethanol, i.p.) conditioned taste aversion (CTA) to saccharin taste. Ethanol‐induced CTA strongly decreased motivation for saccharin in an operant task to obtain the tastant. Comparison of LHb neural firing before and after CTA induction revealed four main differences in firing properties. First, baseline firing after CTA induction was significantly higher. Second, firing evoked by cues signalling saccharin availability shifted from a pattern of primarily inhibition before CTA to primarily excitation after CTA

Dorsal medial prefrontal cortex contributes to conditioned taste aversion memory consolidation and retrieval.

Science.gov (United States)

Gonzalez, Maria Carolina; Villar, Maria Eugenia; Igaz, Lionel M; Viola, Haydée; Medina, Jorge H

2015-12-01

The medial prefrontal cortex (mPFC) is known for its role in decision making and memory processing, including the participation in the formation of extinction memories. However, little is known regarding its contribution to aversive memory consolidation. Here we demonstrate that neural activity and protein synthesis are required in the dorsal mPFC for memory formation of a conditioned taste aversion (CTA) task and that this region is involved in the retrieval of recent and remote long-term CTA memory. In addition, both NMDA receptor and CaMKII activity in dorsal mPFC are needed for CTA memory consolidation, highlighting the complexity of mPFC functions. Copyright © 2015 Elsevier Inc. All rights reserved.

The Commonality of Loss Aversion across Procedures and Stimuli.

Science.gov (United States)

Lee, Sang; Lee, Myung J; Kim, Byoung W; Gilman, Jodi M; Kuster, John K; Blood, Anne J; Kuhnen, Camelia M; Breiter, Hans C

2015-01-01

Individuals tend to give losses approximately 2-fold the weight that they give gains. Such approximations of loss aversion (LA) are almost always measured in the stimulus domain of money, rather than objects or pictures. Recent work on preference-based decision-making with a schedule-less keypress task (relative preference theory, RPT) has provided a mathematical formulation for LA similar to that in prospect theory (PT), but makes no parametric assumptions in the computation of LA, uses a variable tied to communication theory (i.e., the Shannon entropy or information), and works readily with non-monetary stimuli. We evaluated if these distinct frameworks described similar LA in healthy subjects, and found that LA during the anticipation phase of the PT-based task correlated significantly with LA related to the RPT-based task. Given the ease with which non-monetary stimuli can be used on the Internet, or in animal studies, these findings open an extensive range of applications for the study of loss aversion. Furthermore, the emergence of methodology that can be used to measure preference for both social stimuli and money brings a common framework to the evaluation of preference in both social psychology and behavioral economics.

Impact of appetitive and aversive outcomes on brain responses: Linking the animal and human literatures

Directory of Open Access Journals (Sweden)

Gregory B Bissonette

2014-03-01

Full Text Available Decision-making is motivated by the possibility of obtaining reward and/or avoiding punishment. Though many have investigated behavior associated with appetitive or aversive outcomes, few have examined behaviors that rely on both. Fewer still have addressed questions related to how anticipated appetitive and aversive outcomes interact to alter neural signals related to expected value, motivation, and salience. Here we review recent rodent, monkey, and human research that address these issues. Further development of this area will be fundamental to understanding the etiology behind human psychiatric diseases and cultivating more effective treatments.

Ethanol-induced conditioned taste avoidance: reward or aversion?

Science.gov (United States)

Liu, Chuang; Showalter, John; Grigson, Patricia Sue

2009-03-01

Rats avoid intake of a palatable taste cue when paired with all drugs of abuse tested. Evidence suggests that, at least for morphine and cocaine, rats avoid the taste cue because they are anticipating the rewarding properties of the drug. Thus, the suppressive effects of a rewarding sucrose solution and cocaine, but not those of the putatively aversive agent, lithium chloride (LiCl), are exaggerated in drug-sensitive Lewis rats. Likewise, the suppressive effects of sucrose and morphine, but not those of LiCl, are eliminated by bilateral lesions of the gustatory thalamus. Unlike morphine and cocaine, it is less clear whether rewarding or aversive drug properties are responsible for ethanol-induced suppression of intake of a taste cue. The present set of studies tests whether, like cocaine, ethanol-induced suppression of intake of a taste cue also is greater in the drug-sensitive Lewis rats and whether the suppressive effects of the drug are prevented by bilateral lesions of the taste thalamus. In Experiment 1, fluid-deprived Lewis and Fischer rats were given 5-minute access to 0.15% saccharin and then injected with saline or a range of doses of ethanol (0.5, 0.75, 1.0, or 1.5 g/kg). There was a total of 6 such pairings. In Experiments 2 and 3, Sprague-Dawley rats received bilateral electrophysiologically guided lesions of the gustatory thalamus. After recovery, suppression of intake of the saccharin cue was evaluated following repeated daily pairings with either a high (1.5 g/kg) or a low (0.75 g/kg) dose of ethanol. Ethanol-induced suppression of intake of the saccharin conditioned stimulus (CS) did not differ between the drug-sensitive Lewis rats relative to the less-sensitive Fischer rats. Lesions of the taste thalamus, however, prevented the suppressive effect of the 0.75 g/kg dose of the drug, but had no impact on the suppressive effect of the 1.5 g/kg dose of ethanol. The results suggest that the suppressive effects of ethanol on CS intake are mediated by both

Risk aversion and willingness to pay for energy efficient systems in rental apartments

Energy Technology Data Exchange (ETDEWEB)

Farsi, Mehdi [Centre for Energy Policy and Economics, ETH Zurich, Zuerichbergstr. 18, Zurich 8032 (Switzerland)

2010-06-15

This paper uses a random utility model to estimate consumers' valuation of energy efficient insulation and ventilation systems in rental apartments. Given consumers' limited experience in residential buildings and the perceived uncertainty about their comfort benefits and resulting energy savings, these relatively new technologies might be undervalued by risk-averse consumers. Using the concept of certainty-equivalence, this paper proposes a model to assess the consumers' risk-aversion for adopting energy-efficient systems. These systems are treated as risky assets while conventional commodities are assumed to be risk-free. The curvature of the utility function is interpreted as a measure of aversion to perceived risks as opposed to explicit risks measured by observed variances. The proposed formulation is applicable in stated preference data with qualitative variables. The model is applied to data from a choice experiment conducted among 264 apartment tenants in Switzerland. The estimated curvatures reject the risk-neutrality hypothesis. The range of the estimated risk premiums suggests that risk considerations remain a central issue in dealing with energy efficiency in residential buildings. The analysis also indicates that assuming same risk attitudes toward new and conventional systems could bias the estimates of the willingness to pay, especially when the system is comprised of several components. (author)

Risk aversion and willingness to pay for energy efficient systems in rental apartments

International Nuclear Information System (INIS)

Farsi, Mehdi

2010-01-01

This paper uses a random utility model to estimate consumers' valuation of energy efficient insulation and ventilation systems in rental apartments. Given consumers' limited experience in residential buildings and the perceived uncertainty about their comfort benefits and resulting energy savings, these relatively new technologies might be undervalued by risk-averse consumers. Using the concept of certainty-equivalence, this paper proposes a model to assess the consumers' risk-aversion for adopting energy-efficient systems. These systems are treated as risky assets while conventional commodities are assumed to be risk-free. The curvature of the utility function is interpreted as a measure of aversion to perceived risks as opposed to explicit risks measured by observed variances. The proposed formulation is applicable in stated preference data with qualitative variables. The model is applied to data from a choice experiment conducted among 264 apartment tenants in Switzerland. The estimated curvatures reject the risk-neutrality hypothesis. The range of the estimated risk premiums suggests that risk considerations remain a central issue in dealing with energy efficiency in residential buildings. The analysis also indicates that assuming same risk attitudes toward new and conventional systems could bias the estimates of the willingness to pay, especially when the system is comprised of several components.

Roles of octopaminergic and dopaminergic neurons in appetitive and aversive memory recall in an insect.

Science.gov (United States)

Mizunami, Makoto; Unoki, Sae; Mori, Yasuhiro; Hirashima, Daisuke; Hatano, Ai; Matsumoto, Yukihisa

2009-08-04

In insect classical conditioning, octopamine (the invertebrate counterpart of noradrenaline) or dopamine has been suggested to mediate reinforcing properties of appetitive or aversive unconditioned stimulus, respectively. However, the roles of octopaminergic and dopaminergic neurons in memory recall have remained unclear. We studied the roles of octopaminergic and dopaminergic neurons in appetitive and aversive memory recall in olfactory and visual conditioning in crickets. We found that pharmacological blockade of octopamine and dopamine receptors impaired aversive memory recall and appetitive memory recall, respectively, thereby suggesting that activation of octopaminergic and dopaminergic neurons and the resulting release of octopamine and dopamine are needed for appetitive and aversive memory recall, respectively. On the basis of this finding, we propose a new model in which it is assumed that two types of synaptic connections are formed by conditioning and are activated during memory recall, one type being connections from neurons representing conditioned stimulus to neurons inducing conditioned response and the other being connections from neurons representing conditioned stimulus to octopaminergic or dopaminergic neurons representing appetitive or aversive unconditioned stimulus, respectively. The former is called 'stimulus-response connection' and the latter is called 'stimulus-stimulus connection' by theorists studying classical conditioning in higher vertebrates. Our model predicts that pharmacological blockade of octopamine or dopamine receptors during the first stage of second-order conditioning does not impair second-order conditioning, because it impairs the formation of the stimulus-response connection but not the stimulus-stimulus connection. The results of our study with a cross-modal second-order conditioning were in full accordance with this prediction. We suggest that insect classical conditioning involves the formation of two kinds of memory

Mean-Preserving-Spread Risk Aversion and The CAPM

OpenAIRE

Phelim P. Boyle; Chenghu Ma

2013-01-01

This paper establishes conditions under which the classical CAPM holds in equilibrium. Our derivation uses simple arguments to clarify and extend results available in the literature. We show that if agents are risk averse in the sense of mean-preserving-spread (MPS) the CAPM will necessarily hold, along with two-fund separation. We derive this result without imposing any distributional assumptions on asset returns. The CAPM holds even when the market contains an infinite number of securities ...

Choice Behavior Guided by Learned, But Not Innate, Taste Aversion Recruits the Orbitofrontal Cortex.

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Ramírez-Lugo, Leticia; Peñas-Rincón, Ana; Ángeles-Durán, Sandybel; Sotres-Bayon, Francisco

2016-10-12

The ability to select an appropriate behavioral response guided by previous emotional experiences is critical for survival. Although much is known about brain mechanisms underlying emotional associations, little is known about how these associations guide behavior when several choices are available. To address this, we performed local pharmacological inactivations of several cortical regions before retrieval of an aversive memory in choice-based versus no-choice-based conditioned taste aversion (CTA) tasks in rats. Interestingly, we found that inactivation of the orbitofrontal cortex (OFC), but not the dorsal or ventral medial prefrontal cortices, blocked retrieval of choice CTA. However, OFC inactivation left retrieval of no-choice CTA intact, suggesting its role in guiding choice, but not in retrieval of CTA memory. Consistently, OFC activity increased in the choice condition compared with no-choice, as measured with c-Fos immunolabeling. Notably, OFC inactivation did not affect choice behavior when it was guided by innate taste aversion. Consistent with an anterior insular cortex (AIC) involvement in storing taste memories, we found that AIC inactivation impaired retrieval of both choice and no-choice CTA. Therefore, this study provides evidence for OFC's role in guiding choice behavior and shows that this is dissociable from AIC-dependent taste aversion memory. Together, our results suggest that OFC is required and recruited to guide choice selection between options of taste associations relayed from AIC. Survival and mental health depend on being able to choose stimuli not associated with danger. This is particularly important when danger is associated with stimuli that we ingest. Although much is known about the brain mechanisms that underlie associations with dangerous taste stimuli, very little is known about how these stored emotional associations guide behavior when it involves choice. By combining pharmacological and immunohistochemistry tools with taste

Myopic Loss Aversion: Demystifying the Key Factors Influencing Decision Problem Framing

Science.gov (United States)

Hardin, Andrew M.; Looney, Clayton Arlen

2012-01-01

Advancement of myopic loss aversion theory has been hamstrung by conflicting results, methodological inconsistencies, and a piecemeal approach toward understanding the key factors influencing decision problem framing. A series of controlled experiments provides a more holistic view of the variables promoting myopia. Extending the information…

Differential participation of temporal structures in the consolidation and reconsolidation of taste aversion extinction.

Science.gov (United States)

Garcia-Delatorre, Paola; Rodríguez-Ortiz, Carlos J; Balderas, Israela; Bermúdez-Rattoni, Federico

2010-09-01

The extinction process has been described as the decline in the frequency or intensity of the conditioned response following the withdrawal of reinforcement. Hence, experimental extinction does not reflect loss of the original memory, but rather reflects new learning, which in turn requires consolidation in order to be maintained in the long term. During extinction of conditioned taste aversion (CTA), a taste previously associated with aversive consequences acquires a safe status through continuous presentations of the flavor with no aversive consequence. In addition, reconsolidation has been defined as the labile state of a consolidated memory after its reactivation by the presentation of relevant information. In this study, we analyzed structures from the temporal lobe that could be involved in consolidation and reconsolidation of extinction of CTA by means of new protein synthesis. Our results showed that protein synthesis in the hippocampus (HC), the perirhinal cortex (PR) and the insular cortex (IC) of rats participate in extinction consolidation, whereas the basolateral amygdala plays no part in this phenomenon. Furthermore, we found that inhibition of protein synthesis in the IC in a third extinction trial had an effect on reconsolidation of extinction. The participation of the HC in taste memory has been described as a downmodulator for CTA consolidation, and has been related to a context-taste association. Altogether, these data suggest that extinction of aversive taste memories are subserved by the IC, HC and PR, and that extinction can undergo reconsolidation, a process depending only on the IC. © 2010 The Authors. European Journal of Neuroscience © 2010 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

Roles of dopamine neurons in mediating the prediction error in aversive learning in insects.

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Terao, Kanta; Mizunami, Makoto

2017-10-31

In associative learning in mammals, it is widely accepted that the discrepancy, or error, between actual and predicted reward determines whether learning occurs. The prediction error theory has been proposed to account for the finding of a blocking phenomenon, in which pairing of a stimulus X with an unconditioned stimulus (US) could block subsequent association of a second stimulus Y to the US when the two stimuli were paired in compound with the same US. Evidence for this theory, however, has been imperfect since blocking can also be accounted for by competitive theories. We recently reported blocking in classical conditioning of an odor with water reward in crickets. We also reported an "auto-blocking" phenomenon in appetitive learning, which supported the prediction error theory and rejected alternative theories. The presence of auto-blocking also suggested that octopamine neurons mediate reward prediction error signals. Here we show that blocking and auto-blocking occur in aversive learning to associate an odor with salt water (US) in crickets, and our results suggest that dopamine neurons mediate aversive prediction error signals. We conclude that the prediction error theory is applicable to both appetitive learning and aversive learning in insects.

Memory of conditioned taste aversion is erased by inhibition of PI3K in the insular cortex.

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Slouzkey, Ilana; Rosenblum, Kobi; Maroun, Mouna

2013-06-01

The conditioned taste aversion (CTA) paradigm, in which association between a novel taste and visceral malaise is formed, gives a unique experimental setting to examine the mechanisms underlying memory acquisition and extinction processes. AKT is a main kinase of the phosphoinositide 3-kinase cascade (PI3K) and has been implicated in long-term memory. We have recently reported that blockade of PI3K in the basolateral amygdala (BLA) before retrieval of fear memory was associated with long-term reduction in fear responses, suggesting a possible role of PI3K inhibition in fear erasure. In this study, we aimed to elucidate whether PI3K has a similar role in the insular cortex (IC), which has a crucial role in CTA acquisition, consolidation, maintenance, and extinction. To that end, we (1) monitored AKT phosphorylation in the IC following CTA acquisition and extinction and (2) inhibited PI3K by local microinjection of the PI3K inhibitor LY294002 at different stages of CTA acquisition and extinction. Our results show that while AKT phosphorylation is increased following CTA learning, it is decreased following CTA extinction. Inhibition of AKT phosphorylation in the IC before or after the first CTA retrieval test resulted in reduction in the aversion index. This reduction in aversion is due to the erasure of the original CTA trace memory, as re-application of the unconditioned stimulus (lithium chloride) did not induce the recovery of aversion in LY294002-treated animals. Our present data add new evidence to suggest that PI3K is engaged in consolidation of aversive memories, as its inhibition is associated with erasure of CTA memory.

Loss Aversion and Inhibition in Dynamical Models of Multialternative Choice

Science.gov (United States)

Usher, Marius; McClelland, James L.

2004-01-01

The roles of loss aversion and inhibition among alternatives are examined in models of the similarity, compromise, and attraction effects that arise in choices among 3 alternatives differing on 2 attributes. R. M. Roe, J. R. Busemeyer, and J. T. Townsend (2001) have proposed a linear model in which effects previously attributed to loss aversion…

Dine or dash? Turbulence inhibits blue crab navigation in attractive-aversive odor plumes by altering signal structure encoded by the olfactory pathway.

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Weissburg, Marc; Atkins, Lorin; Berkenkamp, Kimberly; Mankin, Danielle

2012-12-01

Blue crabs can distinguish and navigate to attractive (food) odors even when aversive odors (injured crab metabolites) are released nearby. Blue crabs in these conditions detect the aversive odor and avoid it, but find the attractive source with nearly the same success rate as when the attractive source is presented alone. Spatially and temporally distinct odor filaments appear to signal to foragers that the two odor sources are not co-located, and hence navigating to the attractive odor entails an acceptable risk of predation. However, environmentally produced turbulence suppresses tracking by homogenizing the two odors; blue crabs fail to track to the attractive source when the aversive source is present, even though turbulence does not substantially inhibit tracking to the attractive source alone. Removal of sensory input from aesthetascs on the antennules, but not chemosensors on the legs, rescues navigation to attractive-aversive dual plumes in turbulent conditions. These results suggest that mixing in the natural environment may amplify the effects of predators by suppressing tracking to food odors when aversive cues are present, and that the olfactory pathway mediates the response.

Worry-inducing stimuli in an aversive Go/NoGo task enhance reactive control in individuals with lower trait-anxiety.

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Leue, Anja; Rodilla, Carmen Cano; Beauducel, André

2017-04-01

This study relates predictions on reactive and proactive cognitive control to findings on anxious apprehension/worry and ERN/Ne. We investigated whether worry-inducing stimuli in an aversive performance setting lead to a more pronounced increase of the ERN/Ne in individuals with lower anxious apprehension/worry. We also explored the N2 amplitude in the context of worry-inducing stimuli. Fifty-eight participants performed an extended Go/NoGo task. A neutral or fearful face was presented at the beginning of each trial, with the fearful face as a worry-inducing, distracting stimulus. In an aversive feedback condition, aversive feedback was provided for false or too slow responses. We found a more pronounced decrease of the ERN/Ne after worry-inducing stimuli compared to neutral stimuli in participants with lower anxious apprehension/worry. Moreover, less pronounced N2 amplitudes were associated with shorter reaction times in the aversive feedback condition. Implications for future research on error monitoring and trait-anxiety are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact of gender and personality traits (BFI-10) on risk-aversion

DEFF Research Database (Denmark)

Pavlicek, Antonin; Sudzina, Frantisek

2017-01-01

The paper investigates impact of gender and personality traits on risk-aversion. The research was conducted in the Czech Republic using an on-line questionnaire. Data were collected between December 2016 and January 2017. Big Five Inventory-10 was used to measure personality traits. A validated...

Financial literacy, risk aversion and choice of mortgage type by households

NARCIS (Netherlands)

Cox, R.; Brounen, Dirk; Neuteboom, P.

2015-01-01

This paper analyzes how financial literacy and reported willingness to take financial risk impact a household’s choice of mortgage type. The results show that households reporting higher financial literacy and lower risk aversion are 55 to 97 % more likely to opt for interest-only mortgages. The

Chronic stress triggers social aversion via glucocorticoid receptor in dopaminoceptive neurons.

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Barik, Jacques; Marti, Fabio; Morel, Carole; Fernandez, Sebastian P; Lanteri, Christophe; Godeheu, Gérard; Tassin, Jean-Pol; Mombereau, Cédric; Faure, Philippe; Tronche, François

2013-01-18

Repeated traumatic events induce long-lasting behavioral changes that are key to organism adaptation and that affect cognitive, emotional, and social behaviors. Rodents subjected to repeated instances of aggression develop enduring social aversion and increased anxiety. Such repeated aggressions trigger a stress response, resulting in glucocorticoid release and activation of the ascending dopamine (DA) system. We bred mice with selective inactivation of the gene encoding the glucocorticoid receptor (GR) along the DA pathway, and exposed them to repeated aggressions. GR in dopaminoceptive but not DA-releasing neurons specifically promoted social aversion as well as dopaminergic neurochemical and electrophysiological neuroadaptations. Anxiety and fear memories remained unaffected. Acute inhibition of the activity of DA-releasing neurons fully restored social interaction in socially defeated wild-type mice. Our data suggest a GR-dependent neuronal dichotomy for the regulation of emotional and social behaviors, and clearly implicate GR as a link between stress resiliency and dopaminergic tone.

Emotions in cognitive conflicts are not aversive but are task specific.

Science.gov (United States)

Schacht, Annekathrin; Dimigen, Olaf; Sommer, Werner

2010-09-01

It has been suggested that cognitive conflicts require effortful processing and, therefore, are aversive (Botvinick, 2007). In the present study, we compared conflicts emerging from the inhibition of a predominant response tendency in a go/no-go task with those between incompatible response activations in a Simon task in a within-subjects design, using the same type of stimuli. Whereas no-go trials elicited reduced skin conductance and pupillometric responses, but prolonged corrugator muscle activity, as compared with go trials, incompatible and compatible Simon trials were indistinguishable with respect to these parameters. Furthermore, the conflict-sensitive N2 components of the event-related brain potential were similar in amplitude, but showed significantly different scalp distributions, indicating dissociable neural generator systems. The present findings suggest the involvement of different emotional and cognitive processes in both types of cognitive conflicts-none being aversive, however. In addition, the N2 findings call into question claims of common monitoring systems for all kinds of cognitive conflicts.

Light evokes melanopsin-dependent vocalization and neural activation associated with aversive experience in neonatal mice.

Directory of Open Access Journals (Sweden)

Anton Delwig

Full Text Available Melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs are the only functional photoreceptive cells in the eye of newborn mice. Through postnatal day 9, in the absence of functional rods and cones, these ipRGCs mediate a robust avoidance behavior to a light source, termed negative phototaxis. To determine whether this behavior is associated with an aversive experience in neonatal mice, we characterized light-induced vocalizations and patterns of neuronal activation in regions of the brain involved in the processing of aversive and painful stimuli. Light evoked distinct melanopsin-dependent ultrasonic vocalizations identical to those emitted under stressful conditions, such as isolation from the litter. In contrast, light did not evoke the broad-spectrum calls elicited by acute mechanical pain. Using markers of neuronal activation, we found that light induced the immediate-early gene product Fos in the posterior thalamus, a brain region associated with the enhancement of responses to mechanical stimulation of the dura by light, and thought to be the basis for migrainous photophobia. Additionally, light induced the phosphorylation of extracellular-related kinase (pERK in neurons of the central amygdala, an intracellular signal associated with the processing of the aversive aspects of pain. However, light did not activate Fos expression in the spinal trigeminal nucleus caudalis, the primary receptive field for painful stimulation to the head. We conclude that these light-evoked vocalizations and the distinct pattern of brain activation in neonatal mice are consistent with a melanopsin-dependent neural pathway involved in processing light as an aversive but not acutely painful stimulus.

Gamma radiation-induced conditioned taste aversions in rats: A comparison of the protective effects of area postrema lesions with differing doses of radiation

International Nuclear Information System (INIS)

Ossenkopp, K.P.; Giugno, L.

1989-01-01

Lesions which destroy the area postrema (AP) and damage the adjacent nucleus of the solitary tract (NTS) attenuate or abolish conditioned taste aversions (CTA) induced by a variety of pharmacological agents as well as exposure to radiation. In the present experiment, 4 groups of male rats received lesions of AP and 4 groups were given sham lesions. One sham-lesioned and one AP-lesioned group were given a single pairing of 1-hr access to a novel 0.10% sodium saccharin solution followed immediately with exposure to 0, 100, 200, or 400 rad of gamma radiation, respectively. Four days later all groups were given daily two-bottle preference tests (saccharin vs. water) on 4 consecutive days. The sham-lesioned groups exposed to the radiation (100, 200, or 400 rad) developed profound aversions to the saccharin on all test days (p less than 0.001). In contrast, all of the AP-lesioned groups as well as the sham-irradiated (0 rad) sham-lesioned group exhibited strong, comparable (p greater than 0.30) preferences for saccharin. Thus, lesion of AP abolished the radiation-induced CTA at all dose levels of radiation. These results raise the possibility of pharmacological intervention at the level of AP to prevent radiation-induced CTA in cancer patients undergoing radiation therapy

Loss aversion is an affective forecasting error.

Science.gov (United States)

Kermer, Deborah A; Driver-Linn, Erin; Wilson, Timothy D; Gilbert, Daniel T

2006-08-01

Loss aversion occurs because people expect losses to have greater hedonic impact than gains of equal magnitude. In two studies, people predicted that losses in a gambling task would have greater hedonic impact than would gains of equal magnitude, but when people actually gambled, losses did not have as much of an emotional impact as they predicted. People overestimated the hedonic impact of losses because they underestimated their tendency to rationalize losses and overestimated their tendency to dwell on losses. The asymmetrical impact of losses and gains was thus more a property of affective forecasts than a property of affective experience.

The effect of BLA GABAB receptors in anxiolytic-like effect and aversive memory deficit induced by ACPA

Directory of Open Access Journals (Sweden)

Katayoon Kangarlu Haghighi

2016-07-01

Full Text Available Background: As a psychoactive plant, Cannabis sativa (Marijuana is widely used throughout the world. Several investigations have indicated that administration of Marijuana affects various cognitive and non-cognitive behaviors. These include anxiety-like behaviors and learning and memory deficit. It has been shown that three main cannabinoid receptors [i.e. CB1, CB2 and CB3 are involved in cannabinoids’ functions. CB1 receptors are abundantly expressed in the central nervous system regions such as hippocampus, amygdala, cerebellum and the cortex. Therefore, the neuropsychological functions of endocannabinoids are thought to be more linked to CB1 receptors. Among other brain regions, CB1 is highly expressed in the amygdala which is an integral component of the limbic circuitry. The amygdala plays a major role in the control of emotional behavior, including conditioned fear and anxiety. In present study we examined the possible roles of basolateral amygdala (BLA GABAB receptors in arachydonilcyclopropylamide (ACPA-induced anxiolytic-like effect and aversive memory deficit in adult male mice. Methods: This experimental study was conducted from September 2013 to December 2014 in Institute for Studies in Theoretical Physics and Mathematics, School of Cognitive Sciences, Tehran and Male albino NMRI mice (Pasture Institute, Iran, weighting 27-30 g, were used. Bilateral guide-cannulae were implanted to allow intra BLA microinjection of the drugs. We used Elevated Plus Maze (EPM to examine memory and anxiety behavior (test-retest protocol. ACPA administrate intra-peritoneal and GABAB agonist and antagonist administrated intra-amygdala. Results: Data showed that pre-test treatment with ACPA induced anxiolytic-like and aversive memory deficit The results revealed that pre-test intra-BLA infusion of baclofen (GABAB receptor agonist impaired the aversive memory while phaclofen (GABAB receptor antagonist improved it. Interestingly, pretreatment with a sub

The long-term effects of stress and kappa opioid receptor activation on conditioned place aversion in male and female California mice.

Science.gov (United States)

Laman-Maharg, Abigail R; Copeland, Tiffany; Sanchez, Evelyn Ordoñes; Campi, Katharine L; Trainor, Brian C

2017-08-14

Psychosocial stress leads to the activation of kappa opioid receptors (KORs), which induce dysphoria and facilitate depression-like behaviors. However, less is known about the long-term effects of stress and KORs in females. We examined the long-term effects of social defeat stress on the aversive properties of KOR activation in male and female California mice (Peromyscus californicus) using a conditioned place aversion paradigm. Female California mice naïve to social defeat, formed a place aversion following treatment with 2.5mg/kg of the KOR agonist U50,488, but females exposed to defeat did not form a place aversion to this dose. This supports the finding by others that social defeat weakens the aversive properties of KOR agonists. In contrast, both control and stressed males formed an aversion to 10mg/kg of U50,488. We also examined EGR1 immunoreactivity, an indirect marker of neuronal activity, in the nucleus accumbens (NAc) and found that stress and treatment with 10mg/kg of U50,488 increased EGR1 immunoreactivity in the NAc core in females but reduced activation in males. The effects of stress and U50,488 on EGR1 were specific to the NAc, as we found no differences in the bed nucleus of the stria terminalis. In summary, our data indicate important sex differences in the long-term effects of stress and indicate the need for further study of the molecular mechanisms mediating the behavioral effects of KOR in both males and females. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact of Risk Aversion on the Operation of Hydroelectric Reservoirs in the Presence of Renewable Energy Sources

Directory of Open Access Journals (Sweden)

Nenad Jovanović

2018-05-01

Full Text Available The increasing share of renewable energy sources, such as wind and solar generation, has a direct impact on the planning and operation of power systems. In addition, the consideration of risk criteria within the decision support tools used by market participants (generation companies, energy services companies, and arbitrageurs is becoming a common activity given the increasing level of uncertainties faced by them. As a consequence, the behavior of market participants is affected by their level of risk aversion, and the application of equilibrium-based models is a common technique used in order to simulate their behavior. This paper presents a multi-stage market equilibrium model of risk-averse agents in order to analyze up to what extent the operation of hydro reservoirs can be affected by the risk-averse profile of market participants in a context of renewable energy source penetration and fuel price volatility.

Imagery rescripting as a clinical intervention for aversive memories : A meta-analysis

NARCIS (Netherlands)

Morina, N.; Lancee, J.; Arntz, A.

Background and objectives Literature suggests that imagery rescripting (ImRs) is an effective psychological intervention. Methods We conducted a meta-analysis of ImRs for psychological complaints that are associated with aversive memories. Relevant publications were collected from the databases

Sex differences in the effects of ethanol pre-exposure during adolescence on ethanol-induced conditioned taste aversion in adult rats.

Science.gov (United States)

Sherrill, Luke K; Berthold, Claire; Koss, Wendy A; Juraska, Janice M; Gulley, Joshua M

2011-11-20

Alcohol use, which typically begins during adolescence and differs between males and females, is influenced by both the rewarding and aversive properties of the drug. One way adolescent alcohol use may modulate later consumption is by reducing alcohol's aversive properties. Here, we used a conditioned taste aversion (CTA) paradigm to determine if pre-exposure to alcohol (ethanol) during adolescence would attenuate ethanol-induced CTA assessed in adulthood in a sex-dependent manner. Male and female Long-Evans rats were given intraperitoneal (i.p.) injections of saline or 3.0g/kg ethanol in a binge-like pattern during postnatal days (PD) 35-45. In adulthood (>PD 100), rats were given access to 0.1% saccharin, followed by saline or ethanol (1.0 or 1.5g/kg, i.p.), over four conditioning sessions. We found sex differences in ethanol-induced CTA, with males developing a more robust aversion earlier in conditioning. Sex differences in the effects of pre-exposure were also evident: males, but not females, showed an attenuated CTA in adulthood following ethanol pre-exposure, which occurred approximately nine weeks earlier. Taken together, these findings indicate that males are more sensitive to the aversive properties of ethanol than females. In addition, the ability of pre-exposure to the ethanol US to attenuate CTA is enhanced in males compared to females. Copyright © 2011 Elsevier B.V. All rights reserved.

The Commonality of Loss Aversion across Procedures and Stimuli

Science.gov (United States)

Kim, Byoung W.; Gilman, Jodi M.; Kuster, John K.; Blood, Anne J.; Kuhnen, Camelia M.

2015-01-01

Individuals tend to give losses approximately 2-fold the weight that they give gains. Such approximations of loss aversion (LA) are almost always measured in the stimulus domain of money, rather than objects or pictures. Recent work on preference-based decision-making with a schedule-less keypress task (relative preference theory, RPT) has provided a mathematical formulation for LA similar to that in prospect theory (PT), but makes no parametric assumptions in the computation of LA, uses a variable tied to communication theory (i.e., the Shannon entropy or information), and works readily with non-monetary stimuli. We evaluated if these distinct frameworks described similar LA in healthy subjects, and found that LA during the anticipation phase of the PT-based task correlated significantly with LA related to the RPT-based task. Given the ease with which non-monetary stimuli can be used on the Internet, or in animal studies, these findings open an extensive range of applications for the study of loss aversion. Furthermore, the emergence of methodology that can be used to measure preference for both social stimuli and money brings a common framework to the evaluation of preference in both social psychology and behavioral economics. PMID:26394306

The Commonality of Loss Aversion across Procedures and Stimuli.

Directory of Open Access Journals (Sweden)

Sang Lee

Full Text Available Individuals tend to give losses approximately 2-fold the weight that they give gains. Such approximations of loss aversion (LA are almost always measured in the stimulus domain of money, rather than objects or pictures. Recent work on preference-based decision-making with a schedule-less keypress task (relative preference theory, RPT has provided a mathematical formulation for LA similar to that in prospect theory (PT, but makes no parametric assumptions in the computation of LA, uses a variable tied to communication theory (i.e., the Shannon entropy or information, and works readily with non-monetary stimuli. We evaluated if these distinct frameworks described similar LA in healthy subjects, and found that LA during the anticipation phase of the PT-based task correlated significantly with LA related to the RPT-based task. Given the ease with which non-monetary stimuli can be used on the Internet, or in animal studies, these findings open an extensive range of applications for the study of loss aversion. Furthermore, the emergence of methodology that can be used to measure preference for both social stimuli and money brings a common framework to the evaluation of preference in both social psychology and behavioral economics.

Attenuation of a radiation-induced conditioned taste aversion after the development of ethanol tolerance

International Nuclear Information System (INIS)

Hunt, W.A.; Rabin, B.M.

1988-01-01

An attempt to reduce a radiation-induced conditioned taste aversion (CTA) was undertaken by rendering animals tolerant to ethanol. Ethanol tolerance, developed over 5 days, was sufficient to block a radiation-induced taste aversion, as well as an ethanol-induced CTA. Several intermittent doses of ethanol, which did not induce tolerance but removed the novelty of the conditioning stimulus, blocked an ethanol-induced CTA but not the radiation-induced CTA. A CTA induced by doses of radiation up to 500 rads was attenuated. These data suggest that radioprotection developing in association with ethanol tolerance is a result of a physiological response to the chronic presence of ethanol not to the ethanol itself

PERAN PRODUCT CUES AND RISK AVERSION PADA PURCHASE INTENTION DAN POST PURCHASE FEELINGS

Directory of Open Access Journals (Sweden)

Sri Rejeki Ekasasi

2015-11-01

Full Text Available AbstractThe research aimed to investigate the influence of extrinsic cues and intrinsic cues and risk aversion towards purchase intention and post-purchase feeling of counterfeited computer software and music CD. This research study collected data from two populations which are students and employee. Approximately 128 respondents involved to give respond for the survey. The analysis using Structural Equation Model (SEM show that product cues and risk aversion give different significant impact towards purchase intention and post-purchase feeling of counterfeited computer software and music CD. The research concluded that risk aversion and extrinsic cues has a significant influence to purchase intention of counterfeited computer software while it does not appear similar result to music CD. Moreover, the study revealed that for both counterfeited computer software and music CD, the purchase intention is proven to have negative significant influence towards post-purchase feelings.Keywords: risk aversion, extrinsic cues, intrinsic cues, purchase intention, post-purchase feelingsAbstrakTujuan dari penelitian ini adalah untuk melihat pengaruh atribut ekstrinsik dan intrinsic produk serta aspek menolak resiko terhadap niat beli dan perasaan paska beli software computer dan CD music bajakan. Penelitian ini diharapkan akan memperoleh sebuah model dengan pendekatan cultural dan strategi bisnis untuk memblokir atau mengurangi produk bajakan yang dapat diakses konsumen di pasar. Data primer akan dikumpulkan dari dua populasi, kelompok mahasiswa dan kelompok pekerja, dari empat kota besar di Indonesia yaitu Jakarta, Semarang, Surabaya, dan Yogyakarta. Lebih kurang 128 responden terlibat dalam penelitian ini. Hasil penelitian menunjukkan bahwa aspek atribut produk yang bersifat ekstrinsik dan aspek menolak resiko terbukti memiliki hubungan signifikan mempengaruhi niat beli software computer, akan tetapi lain tidak demikian pada niat beli CD music bajakan

Conformists or Rebels? Relative Risk Aversion, Educational Decisions, and Social Class Reproduction

DEFF Research Database (Denmark)

Holm, Anders; Jæger, Mads Meier

2012-01-01

This paper tests the theory of Relative Risk Aversion (RRA), which argues that educational decisions are intended to minimize the risk of downward social class mobility. We propose a structural model which distinguishes the instantaneous utility of educational decisions from the future utility...

Consequences of regret aversion : effects of expected feedback on risky decision making

NARCIS (Netherlands)

Zeelenberg, M.; Beattie, J.; Pligt, van der J.; Vries, de N.K.

1996-01-01

Previous research has considered the question of how anticipated regret affects risky decision making. Several studies have shown that anticipated regret forces participants towards the safe option, showing risk-aversion. We argue that these results are due to the previous confounding of the

Integrated framework for the external cost assessment of nuclear power plant accident considering risk aversion: The Korean case

International Nuclear Information System (INIS)

Lee, Sang Hun; Kang, Hyun Gook

2016-01-01

Recently, the estimation of accident costs within the social costs of nuclear power plants (NPPs) has garnered substantial interest. In particular, the risk aversion behavior of the public toward an NPP accident is considered an important factor when integrating risk aversion into NPP accident cost. In this study, an integrated framework for the external cost assessment of NPP accident that measures the value of statistical life (VSL) and the relative risk aversion (RRA) coefficient for NPP accident based on an individual-level survey is proposed. To derive the willingness to pay and the RRA coefficient for NPP accident risks, a survey was conducted on a sample of 1550 individuals in Korea. The estimation obtained a mean VSL of USD 2.78 million and an RRA coefficient of 1.315. Based on the estimation results in which various cost factors were considered, a multiplication factor of 5.16 and an external cost of NPP accidents of 4.39E−03 USD-cents/kW h were estimated. This study is expected to provide insight to energy policy decision-makers on analyzing the economic validity of NPP compared to other energy sources by reflecting the estimated external cost of NPP accident into the unit electricity generation cost of NPP. - Highlights: •External cost assessment framework for NPP is proposed considering risk aversion. •VSL was derived from WTP for mortality risk reduction from hypothetical NPP accident. •RRA was derived to integrate public risk aversion into external cost of NPP accident. •Individual-level survey was conducted to derive WTP and RRA for NPP accident risk. •The external cost was estimated considering the direct cost factors of NPP accident.

The effects of continuous and intermittent ethanol exposure in adolesence on the aversive properties of ethanol during adulthood.

Science.gov (United States)

Diaz-Granados, Jaime L; Graham, Danielle L

2007-12-01

Alcohol abuse among adolescents is prevalent. Epidemiological studies suggest that alcohol abuse during the adolescent developmental period may result in long-term changes such as an increased susceptibility to alcohol-related problems in adulthood. Laboratory findings suggest that alcohol exposure during the adolescent developmental period, as compared with adulthood, may differentially impact subsequent neurobehavioral responses to alcohol. The present study was designed to examine whether ethanol exposure, continuous versus intermittent, during the adolescent developmental period would alter the aversive properties of ethanol in adult C3H mice. Periadolescent (PD28) male C3H mice were exposed to 64 hours of continuous or intermittent ethanol vapor. As a comparison, adult (PD70) C3H mice were also exposed to 64 hours of continuous or intermittent ethanol vapor. Six weeks after ethanol exposure, taste aversion conditioning was carried out on both ethanol pre-exposed and ethanol-naive animals using a 1-trial, 1-flavor taste-conditioning procedure. Ethanol exposure during the periadolescent period significantly attenuated a subsequent ethanol-induced conditioned taste aversion, as compared with control animals. Adult animals exposed to chronic ethanol vapor during adolescence showed less of an aversion to an ethanol-paired flavor than ethanol-naive adults. Intermittent exposure to ethanol vapor during periadolescence produced a greater attenuation. It is suggested that ethanol exposure during the periadolescent period results in long-term neurobehavioral changes, which lessen a conditioned aversion to ethanol in adulthood. It is suggested that this age-related effect may underlie the increased susceptibility to alcohol-related problems which is negatively correlated with the age of onset for alcohol abuse.

Environmental and Economic Optimization Model for Electric System Planning in Ningxia, China: Inexact Stochastic Risk-Aversion Programming Approach

Directory of Open Access Journals (Sweden)

L. Ji

2015-01-01

Full Text Available The main goal of this paper is to provide a novel risk aversion model for long-term electric power system planning from the manager’s perspective with the consideration of various uncertainties. In the proposed method, interval parameter programming and two-stage stochastic programming are integrated to deal with the technical, economics, and policy uncertainties. Moreover, downside risk theory is introduced to balance the trade-off between the profit and risk according to the decision-maker’s risk aversion attitude. To verify the effectiveness and practical application of this approach, an inexact stochastic risk aversion model is developed for regional electric system planning and management in Ningxia Hui Autonomous Region, China. The series of solutions provide the decision-maker with the optimal investment strategy and operation management under different future emission reduction scenarios and risk-aversion levels. The results indicated that pollution control devices are still the main measures to achieve the current mitigation goal and the adjustment of generation structure would play an important role in the future cleaner electricity system with the stricter environmental policy. In addition, the model can be used for generating decision alternatives and helping decision-makers identify desired energy structure adjustment and pollutants/carbon mitigation abatement policies under various economic and system-reliability constraints.

A single alcohol drinking session is sufficient to enable subsequent aversion-resistant consumption in mice.

Science.gov (United States)

Lei, Kelly; Wegner, Scott A; Yu, Ji-Hwan; Simms, Jeffrey A; Hopf, F Woodward

2016-09-01

Addiction is mediated in large part by pathological motivation for rewarding, addictive substances, and alcohol-use disorders (AUDs) continue to extract a very high physical and economic toll on society. Compulsive alcohol drinking, where intake continues despite negative consequences, is considered a particular obstacle during treatment of AUDs. Aversion-resistant drives for alcohol have been modeled in rodents, where animals continue to consume even when alcohol is adulterated with the bitter tastant quinine, or is paired with another aversive consequence. Here, we describe a two-bottle choice paradigm where C57BL/6 mice first had 24-h access to 15% alcohol or water. Afterward, they drank quinine-free alcohol (alcohol-only) or alcohol with quinine (100 μM), in a limited daily access (LDA) two-bottle-choice paradigm (2 h/day, 5 days/week, starting 3 h into the dark cycle), and achieved nearly binge-level blood alcohol concentrations. Interestingly, a single, initial 24-h experience with alcohol-only enhanced subsequent quinine-resistant drinking. In contrast, mice that drank alcohol-quinine in the 24-h session showed significantly reduced alcohol-quinine intake and preference during the subsequent LDA sessions, relative to mice that drank alcohol-only in the initial 24-h session and alcohol-quinine in LDA sessions. Thus, mice could find the concentration of quinine we used aversive, but were able to disregard the quinine after a single alcohol-only drinking session. Finally, mice had low intake and preference for quinine in water, both before and after weeks of alcohol-drinking sessions, suggesting that quinine resistance was not a consequence of increased quinine preference after weeks of drinking of alcohol-quinine. Together, we demonstrate that a single alcohol-only session was sufficient to enable subsequent aversion-resistant consumption in C57BL/6 mice, which did not reflect changes in quinine taste palatability. Given the rapid development of quinine

Ethanol-induced conditioned taste aversion in male sprague-dawley rats: impact of age and stress.

Science.gov (United States)

Anderson, Rachel I; Varlinskaya, Elena I; Spear, Linda P

2010-12-01

Age-specific characteristics may contribute to the elevation in ethanol intake commonly reported among adolescents compared to adults. This study was designed to examine age-related differences in sensitivity to ethanol's aversive properties using a conditioned taste aversion (CTA) procedure with sucrose serving as the conditioned stimulus (CS). Given that ontogenetic differences in responsiveness to stressors have been previously reported, the role of stressor exposure on the development of CTA was also assessed. Experiment 1 examined the influence of 5 days of prior restraint stress exposure on the expression of CTA in a 2-bottle test following 1 pairing of a sucrose solution with ethanol. In Experiment 2, the effects of 7 days of social isolation on the development of CTA were observed using a 1-bottle test following multiple sucrose-ethanol pairings. This study revealed age-related differences in the development of ethanol-induced CTA. In Experiment 1, adolescents required a higher dose of ethanol than adults to demonstrate an aversion. In Experiment 2, adolescents required not only a higher ethanol dose but also more pairings of ethanol with the sucrose CS. No effects of prior stressor exposure were observed in either experiment. Together, these experiments demonstrate an adolescent-specific insensitivity to the aversive properties of ethanol that elicit CTA, a pattern not influenced by repeated restraint stress or housing in social isolation. This age-related insensitivity to the dysphoric effects of ethanol is consistent with other work from our laboratory, adding further to the evidence that adolescent rats are less susceptible to negative consequences of ethanol that may serve as cues to curb consumption. Copyright © 2010 by the Research Society on Alcoholism.

Aversive properties of negative incentive shifts in Fischer 344 and Lewis rats

Science.gov (United States)

Brewer, Adam; Johnson, Patrick; Stein, Jeff; Schlund, Michael; Williams, Dean C.

2018-01-01

Research on incentive contrast highlights that reward value is not absolute but rather is based upon comparisons we make to rewards we have received and expect to receive. Both human and nonhuman studies on incentive contrast show that shifting from a larger more-valued reward to a smaller less-valued reward is associated with long periods of nonresponding—a negative contrast effect. In this investigation, we used two different genetic rat strains, Fischer 344 and Lewis rats that putatively differ in their sensitivity to aversive stimulation, to assess the aversive properties of large-to-small reward shifts (negative incentive shifts). Additionally, we examined the extent to which increasing cost (fixed-ratio requirements) modulates negative contrast effects. In the presence of a cue that signaled the upcoming reward magnitude, lever pressing was reinforced with one of two different magnitudes of food (large or small). This design created two contrast shifts (small-to-large, large-to-small) and two shifts used as control conditions (small-to-small, large-to-large). Results showed a significant interaction between rat strain and cost requirements only during the negative incentive shift with the emotionally reactive Fischer 344 rats exhibiting significantly longer response latencies with increasing cost, highlighting greater negative contrast. These findings are more consistent with emotionality accounts of negative contrast and results of neurophysiological research that suggests shifting from a large to a small reward is aversive. Findings also highlight how subjective reward value and motivation is a product of gene-environment interactions. PMID:27864048

Time of day-dependent latent inhibition of conditioned taste aversions in rats

Czech Academy of Sciences Publication Activity Database

Manrique, T.; Molero, A.; Ballesteros, M. A.; Morón, I.; Gallo, M.; Fenton, André Antonio

2004-01-01

Roč. 82, č. 2 (2004), s. 77-80 ISSN 1074-7427 Grant - others:CICYT(ES) BSO2002-01215 Institutional research plan: CEZ:AV0Z5011922 Keywords : condition taste aversion * latent inhibition * temporal context Subject RIV: FH - Neurology Impact factor: 4.443, year: 2004

Risk-averse and Risk-seeking Investor Preferences for Oil Spot and Futures

NARCIS (Netherlands)

H.H. Lean (Hooi Hooi); M.J. McAleer (Michael); W.-K. Wong (Wing-Keung)

2013-01-01

textabstractThis paper examines risk-averse and risk-seeking investor preferences for oil spot and futures prices by using the mean-variance (MV) criterion and stochastic dominance (SD) approach. The MV findings cannot distinguish between the preferences of spot and futures markets. However, the SD

Hyperoxia-triggered aversion behavior in Drosophila foraging larvae is mediated by sensory detection of hydrogen peroxide.

Science.gov (United States)

Kim, Myung Jun; Ainsley, Joshua A; Carder, Justin W; Johnson, Wayne A

2013-12-01

Reactive oxygen species (ROS) in excess have been implicated in numerous chronic illnesses, including asthma, diabetes, aging, cardiovascular disease, and neurodegenerative illness. However, at lower concentrations, ROS can also serve essential routine functions as part of cellular signal transduction pathways. As products of atmospheric oxygen, ROS-mediated signals can function to coordinate external environmental conditions with growth and development. A central challenge has been a mechanistic distinction between the toxic effects of oxidative stress and endogenous ROS functions occurring at much lower concentrations. Drosophila larval aerotactic behavioral assays revealed strong developmentally regulated aversion to mild hyperoxia mediated by H2O2-dependent activation of class IV multidendritic (mdIV) sensory neurons expressing the Degenerin/epithelial Na(+) channel subunit, Pickpocket1 (PPK1). Electrophysiological recordings in foraging-stage larvae (78-84 h after egg laying [AEL]) demonstrated PPK1-dependent activation of mdIV neurons by nanomolar levels of H2O2 well below levels normally associated with oxidative stress. Acute sensitivity was reduced > 100-fold during the larval developmental transition to wandering stage (> 96 h AEL), corresponding to a loss of hyperoxia aversion behavior during the same period. Degradation of endogenous H2O2 by transgenic overexpression of catalase in larval epidermis caused a suppression of hyperoxia aversion behavior. Conversely, disruption of endogenous catalase activity using a UAS-CatRNAi transposon resulted in an enhanced hyperoxia-aversive response. These results demonstrate an essential role for low-level endogenous H2O2 as an environment-derived signal coordinating developmental behavioral transitions.

Under pressure: adolescent substance users show exaggerated neural processing of aversive interoceptive stimuli

NARCIS (Netherlands)

Berk, L.; Stewart, J.L.; May, A.C.; Wiers, R.W.; Davenport, P.W.; Paulus, M.P.; Tapert, S.F.

2015-01-01

Aims: Adolescents with substance use disorders (SUD) exhibit hyposensitivity to pleasant internally generated (interoceptive) stimuli and hypersensitivity to external rewarding stimuli. It is unclear whether similar patterns exist for aversive interoceptive stimuli. We compared activation in the

Age-related striatal BOLD changes without changes in behavioral loss aversion

Science.gov (United States)

Viswanathan, Vijay; Lee, Sang; Gilman, Jodi M.; Kim, Byoung Woo; Lee, Nick; Chamberlain, Laura; Livengood, Sherri L.; Raman, Kalyan; Lee, Myung Joo; Kuster, Jake; Stern, Daniel B.; Calder, Bobby; Mulhern, Frank J.; Blood, Anne J.; Breiter, Hans C.

2015-01-01

Loss aversion (LA), the idea that negative valuations have a higher psychological impact than positive ones, is considered an important variable in consumer research. The literature on aging and behavior suggests older individuals may show more LA, although it is not clear if this is an effect of aging in general (as in the continuum from age 20 and 50 years), or of the state of older age (e.g., past age 65 years). We also have not yet identified the potential biological effects of aging on the neural processing of LA. In the current study we used a cohort of subjects with a 30 year range of ages, and performed whole brain functional MRI (fMRI) to examine the ventral striatum/nucleus accumbens (VS/NAc) response during a passive viewing of affective faces with model-based fMRI analysis incorporating behavioral data from a validated approach/avoidance task with the same stimuli. Our a priori focus on the VS/NAc was based on (1) the VS/NAc being a central region for reward/aversion processing; (2) its activation to both positive and negative stimuli; (3) its reported involvement with tracking LA. LA from approach/avoidance to affective faces showed excellent fidelity to published measures of LA. Imaging results were then compared to the behavioral measure of LA using the same affective faces. Although there was no relationship between age and LA, we observed increasing neural differential sensitivity (NDS) of the VS/NAc to avoidance responses (negative valuations) relative to approach responses (positive valuations) with increasing age. These findings suggest that a central region for reward/aversion processing changes with age, and may require more activation to produce the same LA behavior as in younger individuals, consistent with the idea of neural efficiency observed with high IQ individuals showing less brain activation to complete the same task. PMID:25983682

Age-related striatal BOLD changes without changes in behavioral loss aversion

Directory of Open Access Journals (Sweden)

Hans C Breiter

2015-04-01

Full Text Available Loss aversion (LA, the idea that negative valuations have a higher psychological impact than positive ones, is considered an important variable in consumer research. The literature on aging and behavior suggests older individuals may show more LA, although it is not clear if this is an effect of aging in general (as in the continuum from age 20 and 50 years, or of the state of older age (e.g., past age 65 years. We also have not yet identified the potential biological effects of aging on the neural processing of LA. In the current study we used a cohort of subjects with a 30 year range of ages, and performed whole brain functional MRI (fMRI to examine the ventral striatum/nucleus accumbens (VS/NAc response during a passive viewing of affective faces with model-based fMRI analysis incorporating behavioral data from a validated approach/avoidance task with the same stimuli. Our a priori focus on the VS/NAc was based on (1 the VS/NAc being a central region for reward/aversion processing, (2 its activation to both positive and negative stimuli, (3 its reported involvement with tracking LA. LA from approach/avoidance to affective faces showed excellent fidelity to published measures of LA. Imaging results were then compared to the behavioral measure of LA using the same affective faces. Although there was no relationship between age and LA, we observed increasing neural differential sensitivity (NDS of the VS/NAc to avoidance responses (negative valuations relative to approach responses (positive valuations with increasing age. These findings suggest that a central region for reward/aversion processing changes with age, and may require more activation to produce the same LA behavior as in younger individuals, consistent with the idea of neural efficiency observed with high IQ individuals showing less brain activation to complete the same task.

Age-related striatal BOLD changes without changes in behavioral loss aversion.

Science.gov (United States)

Viswanathan, Vijay; Lee, Sang; Gilman, Jodi M; Kim, Byoung Woo; Lee, Nick; Chamberlain, Laura; Livengood, Sherri L; Raman, Kalyan; Lee, Myung Joo; Kuster, Jake; Stern, Daniel B; Calder, Bobby; Mulhern, Frank J; Blood, Anne J; Breiter, Hans C

2015-01-01

Loss aversion (LA), the idea that negative valuations have a higher psychological impact than positive ones, is considered an important variable in consumer research. The literature on aging and behavior suggests older individuals may show more LA, although it is not clear if this is an effect of aging in general (as in the continuum from age 20 and 50 years), or of the state of older age (e.g., past age 65 years). We also have not yet identified the potential biological effects of aging on the neural processing of LA. In the current study we used a cohort of subjects with a 30 year range of ages, and performed whole brain functional MRI (fMRI) to examine the ventral striatum/nucleus accumbens (VS/NAc) response during a passive viewing of affective faces with model-based fMRI analysis incorporating behavioral data from a validated approach/avoidance task with the same stimuli. Our a priori focus on the VS/NAc was based on (1) the VS/NAc being a central region for reward/aversion processing; (2) its activation to both positive and negative stimuli; (3) its reported involvement with tracking LA. LA from approach/avoidance to affective faces showed excellent fidelity to published measures of LA. Imaging results were then compared to the behavioral measure of LA using the same affective faces. Although there was no relationship between age and LA, we observed increasing neural differential sensitivity (NDS) of the VS/NAc to avoidance responses (negative valuations) relative to approach responses (positive valuations) with increasing age. These findings suggest that a central region for reward/aversion processing changes with age, and may require more activation to produce the same LA behavior as in younger individuals, consistent with the idea of neural efficiency observed with high IQ individuals showing less brain activation to complete the same task.

Building physiological toughness: Some aversive events during extinction may attenuate return of fear.

Science.gov (United States)

Culver, Najwa C; Stevens, Stephan; Fanselow, Michael S; Craske, Michelle G

2018-03-01

Although exposure therapy is an effective treatment for anxiety disorders, fear sometimes returns following successful therapy. Recent literature in animal models indicates that incorporating some aversive events into extinction training may offset these return of fear effects. The effect of occasional reinforced extinction trials was investigated in a sample of thirty-nine participants using a fear conditioning and extinction paradigm. Participants either underwent traditional extinction procedures during which the conditional stimulus which had been paired with the unconditional stimulus (US) during acquisition training (CS+) was presented alone with no presentations of the US or partially reinforced extinction during which there were several unpredicted CS+/US pairings. As measured by skin conductance responses, physiological fear responding remained elevated during extinction for participants who experienced partially reinforced extinction; however, these participants demonstrated protection from rapid reacquisition effects. Results from the subjective US-expectancy ratings did not provide evidence of protection against rapid reacquisition in the partially reinforced extinction group; however, there was evidence of protection from spontaneous recovery effects. Lastly, as measured by valence ratings, it was unclear whether partially reinforced extinction provided protection from fear recovery effects. Although participants who experienced partially reinforced extinction demonstrated protection from rapid reacquisition as measured by skin conductance responses, they also demonstrated significantly higher levels of physiological fear responding during extinction which made the results of the spontaneous recovery test more difficult to interpret. Occasional CS-US pairings during extinction may protect against return of fear effects. Clinical implications are discussed. Published by Elsevier Ltd.

Effects of aversive stimuli on prospective memory. An event-related fMRI study.

Directory of Open Access Journals (Sweden)

Massimiliano Rea

Full Text Available Prospective memory (PM describes the ability to execute a previously planned action at the appropriate point in time. Although behavioral studies clearly showed that prospective memory performance is affected by the emotional significance attributed to the intended action, no study so far investigated the brain mechanisms subserving the modulatory effect of emotional salience on PM performance. The general aim of the present study was to explore brain regions involved in prospective memory processes when PM cues are associated with emotional stimuli. In particular, based on the hypothesised critical role of the prefrontal cortex in prospective memory in the presence of emotionally salient stimuli, we expected a stronger involvement of aPFC when the retrieval and execution of the intended action is cued by an aversive stimulus. To this aim BOLD responses of PM trials cued by aversive facial expressions were compared to PM trials cued by neutral facial expressions. Whole brain analysis showed that PM task cued by aversive stimuli is differentially associated with activity in the right lateral prefrontal area (BA 10 and in the left caudate nucleus. Moreover a temporal shift between the response of the caudate nucleus that preceded that of aPFC was observed. These findings suggest that the caudate nucleus might provide an early analysis of the affective properties of the stimuli, whereas the anterior lateral prefrontal cortex (BA10 would be involved in a slower and more deliberative analysis to guide goal-directed behaviour.

Cooperative game analysis of a supply chain with one risk-neutral supplier and two risk-averse retailers

Directory of Open Access Journals (Sweden)

Changwen Li

2014-09-01

Full Text Available Purpose: This paper considers a two-echelon supply chain composed of one risk-neutral supplier and two risk-averse retailers. The retailers obtain production from the supplier and sell them to the market. Based on the cooperative game theory, the paper studies the appropriate profit allocation of the supply chain when all the players cooperate with each other, where the two retailers face a price-sensitive stochastic demand. The two retailers can either determine their retail prices independently, or decide whether or not to cooperate with each other. Design/methodology/approach: To allocate the system-wide profit among upstream risk-neutral suppliers and two risk-averse downstream retailers, this paper constructed a cooperative game model, considered as the supermodularity of the characteristic function and the Shapley value of the game. Findings and Originality/value: By analyzing the construction’s cooperative game model, the results show that the profit of the whole supply chain is the highest in the grand coalition structure. This paper also shows that the core of our cooperative game is nonempty, and has the supermodularity property. Based on this, we have computed the Shapley value-based profit allocation for the whole supply chain in a fair manner. Originality/value: Although there are a lot of literature examined risk aversion in a supply chain, but they did not consider using cooperative game to study this problem. This the first study is in the context of a supply chain with risk aversion problem.

Cue-elicited food seeking is eliminated with aversive outcomes following outcome devaluation.

Science.gov (United States)

Eder, Andreas B; Dignath, David

2016-01-01

In outcome-selective Pavlovian-to-instrumental transfer (PIT), stimuli that are predictive of specific outcomes prime instrumental responses that are associated with these outcomes. Previous human studies yielded mixed evidence in respect to whether the PIT effect is affected by a posttraining devaluation of an outcome, with the PIT effect being preserved after a devaluation of a primary reinforcer (food, drugs) but not following the devaluation of a secondary reinforcer (money). The present research examined whether outcome-selective transfer is eliminated when the devaluation of a primary (liquid) reinforcer is strong and aversive. Experiment 1 confirmed these expectations following a devaluation with bad tasting Tween 20. However, outcome-selective transfer was still observed when the earned (devalued) outcome was not consumed immediately after each test (Experiment 2). These results suggest that the capacity of a Pavlovian cue to motivate a specific response is affected by the incentive value of the shared outcome only when the devaluation yields an aversive outcome that is consumed immediately.

The Yerkes-Dodson law and appropriate stimuli for conditioned taste aversion in Lymnaea.

Science.gov (United States)

Ito, Etsuro; Yamagishi, Miki; Takigami, Satoshi; Sakakibara, Manabu; Fujito, Yutaka; Lukowiak, Ken

2015-02-01

The pond snail Lymnaea stagnalis can learn conditioned taste aversion and then consolidate it into long-term memory (LTM). A high-voltage electric shock was used as the unconditioned stimulus, where we have previously used KCl. We varied the strength of both the conditioned and unconditioned stimuli to determine whether the so-called Yerkes-Dodson law prevailed. This is an empirical relationship between the state of arousal and LTM formation, showing that there is an optimal level of arousal leading to memory formation. However, too little or too much arousal results in poorer LTM. We found here that the most appropriate stimuli to use in taste aversion training in Lymnaea were a 10 mmol l(-1) sucrose solution as the conditioned stimulus and a 3 s electric shock as the unconditioned stimulus. © 2015. Published by The Company of Biologists Ltd.

"A Lifelong Aversion to Writing": What if Writing Courses Emphasized Motivation?

Science.gov (United States)

Sullivan, Patrick

2011-01-01

There has been a great deal of groundbreaking research done on motivation during the last twenty-five years, and all of it points to the importance of intrinsic motivation. This research has very significant ramifications for teachers of English. In this essay, the author engages the issue of "aversion" that Linda Brodkey raises in her essay…

The Unspoken Consequence of Command, Control Communications Technology: Enhanced Micromanagement by Risk-Averse Commanders

National Research Council Canada - National Science Library

Carozza, John

2004-01-01

.... However, along with its benefits, this command, control and communications (C3) network includes the dangerous consequence of eroding the autonomy of tactical command through enhanced micromanagement by risk-averse operational commanders...

Money, well-being, and loss aversion: does an income loss have a greater effect on well-being than an equivalent income gain?

Science.gov (United States)

Boyce, Christopher J; Wood, Alex M; Banks, James; Clark, Andrew E; Brown, Gordon D A

2013-12-01

Higher income is associated with greater well-being, but do income gains and losses affect well-being differently? Loss aversion, whereby losses loom larger than gains, is typically examined in relation to decisions about anticipated outcomes. Here, using subjective-well-being data from Germany (N = 28,723) and the United Kingdom (N = 20,570), we found that losses in income have a larger effect on well-being than equivalent income gains and that this effect is not explained by diminishing marginal benefits of income to well-being. Our findings show that loss aversion applies to experienced losses, challenging suggestions that loss aversion is only an affective-forecasting error. By failing to account for loss aversion, longitudinal studies of the relationship between income and well-being may have overestimated the positive effect of income on well-being. Moreover, societal well-being might best be served by small and stable income increases, even if such stability impairs long-term income growth.

CAMKII inhibition in the parabrachial nuclei elicits conditioned taste aversion in rats

Czech Academy of Sciences Publication Activity Database

Sacchetti, B.; Baldi, E.; Tassoni, G.; Bielavská, Edita

2001-01-01

Roč. 75, č. 3 (2001), s. 253-261 ISSN 1074-7427 R&D Projects: GA AV ČR IAA7011706 Institutional research plan: CEZ:AV0Z5011922 Keywords : CA2+/calmodulin-dependent protein kinase * conditioned taste aversion Subject RIV: FH - Neurology Impact factor: 1.830, year: 2001

Deciding for Others Reduces Loss Aversion

DEFF Research Database (Denmark)

Andersson, Ola; Holm, Håkan J.; Tyran, Jean-Robert Karl

We study risk taking on behalf of others, both with and without potential losses. A large-scale incentivized experiment is conducted with subjects randomly drawn from the Danish population. On average, decision makers take the same risks for other people as for themselves when losses are excluded....... In contrast, when losses are possible, decisions on behalf of others are more risky. Using structural estimation, we show that this increase in risk stems from a decrease in loss aversion when others are affected by their choices.......We study risk taking on behalf of others, both with and without potential losses. A large-scale incentivized experiment is conducted with subjects randomly drawn from the Danish population. On average, decision makers take the same risks for other people as for themselves when losses are excluded...

What are the elements of motivation for acquisition of conditioned taste aversion?

Science.gov (United States)

Mita, Koichi; Okuta, Akiko; Okada, Ryuichi; Hatakeyama, Dai; Otsuka, Emi; Yamagishi, Miki; Morikawa, Mika; Naganuma, Yuki; Fujito, Yutaka; Dyakonova, Varvara; Lukowiak, Ken; Ito, Etsuro

2014-01-01

The pond snail Lymnaea stagnalis is capable of being classically conditioned to avoid food and to consolidate this aversion into a long-term memory (LTM). Previous studies have shown that the length of food deprivation is important for both the acquisition of taste aversion and its consolidation into LTM, which is referred to as conditioned taste aversion (CTA). Here we tested the hypothesis that the hemolymph glucose concentration is an important factor in the learning and memory of CTA. One-day food deprivation resulted in the best learning and memory, whereas more prolonged food deprivation had diminishing effects. Five-day food deprivation resulted in snails incapable of learning or remembering. During this food deprivation period, the hemolymph glucose concentration decreased. If snails were fed for 2days following the 5-day food deprivation, their glucose levels increased significantly and they exhibited both learning and memory, but neither learning nor memory was as good as with the 1-day food-deprived snails. Injection of the snails with insulin to reduce glucose levels resulted in better learning and memory. Insulin is also known to cause a long-term enhancement of synaptic transmission between the feeding-related neurons. On the other hand, injection of glucose into 5-day food-deprived snails did not alter their inability to learn and remember. However, if these snails were fed on sucrose for 3min, they then exhibited learning and memory formation. Our data suggest that hemolymph glucose concentration is an important factor in motivating acquisition of CTA in Lymnaea and that the action of insulin in the brain and the feeding behavior are also important factors. Copyright © 2013 Elsevier Inc. All rights reserved.

Transdiagnostic Psychiatric Symptoms and Event-Related Potentials following Rewarding and Aversive Outcomes.

Directory of Open Access Journals (Sweden)

Jeffrey S Bedwell

Full Text Available There is a need for a better understanding of transdiagnostic psychiatric symptoms that relate to neurophysiological abnormalities following rewarding and aversive feedback in order to inform development of novel targeted treatments. To address this need, we examined a transdiagnostic sample of 44 adults (mean age: 35.52; 57% female, which consisted of individuals with broadly-defined schizophrenia-spectrum disorders (n = 16, bipolar disorders (n = 10, other mood and anxiety disorders (n = 5, and no history of a psychiatric disorder (n = 13. Participants completed a Pavlovian monetary reward prediction task during 32-channel electroencephalogram recording. We assessed the event-related potentials (ERPs of feedback-related negativity (FRN, feedback-related positivity (FRP, and the late positive potential (LPP, following better and worse than expected outcomes. Examination of symptom relationships using stepwise regressions across the entire sample revealed that an increase in the clinician-rated Negative Symptoms factor score from the Positive and Negative Syndrome Scale, was related to a decreased LPP amplitude during better than expected (i.e., rewarding outcomes. We also found that increased self-reported scores on the Schizotypal Personality Questionnaire (Brief-Revised Disorganized factor related to an increased FRN amplitude during worse than expected (i.e., aversive outcomes. Across the entire sample, the FRP component amplitudes did not show significant relationships to any of the symptoms examined. Analyses of the three diagnostic groups of schizophrenia-spectrum disorders, bipolar disorders, and nonpsychiatric controls did not reveal any statistically significant differences across the ERP amplitudes and conditions. These findings suggest relationships between specific neurophysiological abnormalities following rewarding and aversive outcomes and particular transdiagnostic psychiatric symptoms.

Health Security and Risk Aversion.

Science.gov (United States)

Herington, Jonathan

2016-09-01

Health security has become a popular way of justifying efforts to control catastrophic threats to public health. Unfortunately, there has been little analysis of the concept of health security, nor the relationship between health security and other potential aims of public health policy. In this paper I develop an account of health security as an aversion to risky policy options. I explore three reasons for thinking risk avoidance is a distinctly worthwhile aim of public health policy: (i) that security is intrinsically valuable, (ii) that it is necessary for social planning and (iii) that it is an appropriate response to decision-making in contexts of very limited information. Striking the right balance between securing and maximizing population health thus requires a substantive, and hitherto unrecognized, value judgment. Finally, I critically evaluate the current health security agenda in light of this new account of the concept and its relationship to the other aims of public health policy. © 2016 John Wiley & Sons Ltd.

Potential Impact of Risk and Loss Aversion on the Process of Accepting Kidneys for Transplantation.

Science.gov (United States)

Heilman, Raymond L; Green, Ellen P; Reddy, Kunam S; Moss, Adyr; Kaplan, Bruce

2017-07-01

Behavioral economic theory suggests that people make decisions based on maximizing perceived value; however, this may be influenced more by the risk of loss rather than of potential gain. Additionally, individuals may seek certainty over uncertainty. These are termed loss aversion and risk aversion, respectively. Loss aversion is particularly sensitive to how the decision is "framed." Thus, labeling a kidney as high Kidney Donor Profile Index results in higher discard rates because this creates a nonlinearity in perceived risk. There is also evidence that the perceived loss due to regulatory sanction results in increased organ discard rates. This may be due to the overuse of terminology that stresses regulatory sanctions and thus perpetuates fear of loss through a form of nudging. Our goal is to point out how these concepts of behavioral economics may negatively influence the decision process to accept these suboptimal organs. We hope to make the community more aware of these powerful psychological influences and thus potentially increase the utilization of these suboptimal organs. Further, we would urge regulatory bodies to avoid utilizing strategies that frame outcomes in terms of loss due to flagging and build models that are less prone to uncertain expected versus observed outcomes.

Inequity-aversion and relative kindness intention jointly determine the expenditure of effort in project teams.

Directory of Open Access Journals (Sweden)

Jiaojie Han

Full Text Available The literature on team cooperation has neglected the effects of relative kindness intention on cooperation, which we measure by comparing the kindness intentions of an agent to her group members to the kindness shown by other members to this same agent. We argue that the agent's emotional reaction to material payoff inequity is not constant, but rather affected by her relative kindness intention. Then, we apply the model to team projects with multiple partners and investigate how inequity-aversion and relative kindness intention jointly influence team cooperation. We first consider the case of homogeneous agents, where their marginal productivity levels and technical capacities are the same, and then consider the case of heterogeneous agents, where their marginal productivity levels and technical capacities are not the same. Our results show that inequity-aversion has no effect on effort expenditure in the former case, but does affect it in the latter case. The consideration of relative kindness intention may impact the agents' optimal cooperative effort expenditure when their technical capacities are different. In addition, it is beneficial for team cooperation, and might not only reduce the negative impact but also enhance the positive impact of inequity-aversion on the agents' effort expenditures.

The combination of appetitive and aversive reinforcers and the nature of their interaction during auditory learning.

Science.gov (United States)

Ilango, A; Wetzel, W; Scheich, H; Ohl, F W

2010-03-31

Learned changes in behavior can be elicited by either appetitive or aversive reinforcers. It is, however, not clear whether the two types of motivation, (approaching appetitive stimuli and avoiding aversive stimuli) drive learning in the same or different ways, nor is their interaction understood in situations where the two types are combined in a single experiment. To investigate this question we have developed a novel learning paradigm for Mongolian gerbils, which not only allows rewards and punishments to be presented in isolation or in combination with each other, but also can use these opposite reinforcers to drive the same learned behavior. Specifically, we studied learning of tone-conditioned hurdle crossing in a shuttle box driven by either an appetitive reinforcer (brain stimulation reward) or an aversive reinforcer (electrical footshock), or by a combination of both. Combination of the two reinforcers potentiated speed of acquisition, led to maximum possible performance, and delayed extinction as compared to either reinforcer alone. Additional experiments, using partial reinforcement protocols and experiments in which one of the reinforcers was omitted after the animals had been previously trained with the combination of both reinforcers, indicated that appetitive and aversive reinforcers operated together but acted in different ways: in this particular experimental context, punishment appeared to be more effective for initial acquisition and reward more effective to maintain a high level of conditioned responses (CRs). The results imply that learning mechanisms in problem solving were maximally effective when the initial punishment of mistakes was combined with the subsequent rewarding of correct performance. Copyright 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

Coordinating a Supply Chain with a Loss-Averse Retailer under Yield and Demand Uncertainties

Directory of Open Access Journals (Sweden)

Weiwei Luo

2016-01-01

Full Text Available This paper investigates the channel coordination of a supply chain (SC consisting of a loss-averse retailer and a risk-neutral supplier under yield and demand uncertainties. Three existing contracts are analyzed. Our results demonstrate that the buyback (BB and quantity flexibility (QF contracts can not only coordinate the supply chain but also lead to Pareto improvement for each player, while the wholesale price (WP contract fails to coordinate the chain due to the effects of double marginalization and risk preference. For comparison, a chain with a risk-neutral retailer is also analyzed. Furthermore, numerical examples are provided to demonstrate the effectiveness of the coordination contracts, and the impacts of loss aversion and random yield on the decision-making behaviors and system performance are then discussed.

Coordinating Contracts for Two-Stage Fashion Supply Chain with Risk-Averse Retailer and Price-Dependent Demand

Directory of Open Access Journals (Sweden)

Minli Xu

2013-01-01

Full Text Available When the demand is sensitive to retail price, revenue sharing contract and two-part tariff contract have been shown to be able to coordinate supply chains with risk neutral agents. We extend the previous studies to consider a risk-averse retailer in a two-echelon fashion supply chain. Based on the classic mean-variance approach in finance, the issue of channel coordination in a fashion supply chain with risk-averse retailer and price-dependent demand is investigated. We propose both single contracts and joint contracts to achieve supply chain coordination. We find that the coordinating revenue sharing contract and two-part tariff contract in the supply chain with risk neutral agents are still useful to coordinate the supply chain taking into account the degree of risk aversion of fashion retailer, whereas a more complex sales rebate and penalty (SRP contract fails to do so. When using combined contracts to coordinate the supply chain, we demonstrate that only revenue sharing with two-part tariff contract can coordinate the fashion supply chain. The optimal conditions for contract parameters to achieve channel coordination are determined. Numerical analysis is presented to supplement the results and more insights are gained.

Aversive Racism and Intergroup Contact Theories: Cultural Competence in a Segregated World

Science.gov (United States)

Rodenborg, Nancy A.; Boisen, Laura A.

2013-01-01

The United States remains highly segregated, and social work students are likely to live and work in segregated contexts. What implications does this have for their cultural competence? Does segregation affect social workers' ability to serve diverse clients without bias? This article reviews two social psychology theories, aversive racism…

The Influence of Financial Literacy, Risk Aversion and Expectations on Retirement Planning and Portfolio Allocation in Malaysia

Directory of Open Access Journals (Sweden)

Nurul Shahnaz Mahdzan

2018-12-01

Full Text Available The two objectives of this paper are to examine the effect of financial literacy, risk aversion and expectations on retirement planning; and, to investigate the effect of these antecedents on the retire- ment portfolio allocation. Data was collected via a self-administered questionnaire from a sample of 270 working individuals in Kuala Lumpur, Malaysia. Logistic and ordered probit regressions were employed to analyse the first and second objective, respectively. The results from the logistic regression indicate that future expectations significantly influence the probability of planning for retirement. Meanwhile, individu- als with higher financial literacy and lower risk aversion are more likely to hold risky assets in their retirement portfolios. Subsequently, two-sample t-test and one-way ANOVA tests were conducted to further examine the differences in financial literacy, risk aversion and expectations, across demographic sub-groups. The study contributes to the literature by holistically incorporating the behavioural aspects that affect retirement planning and by exploring an uncharted issue of retirement planning—namely, the retirement portfolio allocation.

The endowment effect, status quo bias and loss aversion: rational alternative explanation

NARCIS (Netherlands)

Dupont, D.Y.; Lee, Gabriel S.

2002-01-01

The endowment effect, status quo bias, and loss aversion are robust and well documented results from experimental psychology. They introduce a wedge between the prices at which one is willing to sell or buy a good. The objective of this paper is to address this wedge. We show that the presence of

The endowment effect, status quo bias and loss aversion : rational alternative explanation

NARCIS (Netherlands)

Dupont, D.Y.; Lee, G.S.

2002-01-01

The endowment effect, status quo bias, and loss aversion are robust and well documented results from experimental psychology. They introduce a wedge between the prices at which one is willing to sell or buy a good. The objective of this paper is to address this wedge. We show that the presence of

Loss-Aversion or Loss-Attention: The Impact of Losses on Cognitive Performance

Science.gov (United States)

Yechiam, Eldad; Hochman, Guy

2013-01-01

Losses were found to improve cognitive performance, and this has been commonly explained by increased weighting of losses compared to gains (i.e., loss aversion). We examine whether effects of losses on performance could be modulated by two alternative processes: an attentional effect leading to increased sensitivity to task incentives; and a…

Loss aversion, social comparison and physical abilities at younge age

OpenAIRE

Nakamoto, Yasuhiro; Sato, Masayuki

2011-01-01

We examine the relationship between competitive behavior and social comparison where in this paper competitive behavior is measured by physical ability performance. In particular, by incorporating social comparison into prospect theory, we directly estimate the degree of loss aversion with social comparison, a concept we term `ALJ' (Avoiding Loss relative to the Joneses). Our main findings are as follows: (i) the estimated value function is refracted at another's gain and the average estimate...

The Emotional Information Processing System is Risk Averse: Ego-Depletion and Investment Behavior

NARCIS (Netherlands)

B. de Langhe (Bart); S.T.L.R. Sweldens (Steven); S.M.J. van Osselaer (Stijn); M.A. Tuk (Mirjam)

2008-01-01

textabstractTwo experiments show that a shortage of self-regulatory resources results in more risk aversion in mixed-gamble (gain/loss) situations. The findings support a dual process view that distinguishes between a rational and an affective information processing system, in which self-regulatory

Risk and Interaction Aversion: Screening Mechanisms in the Prisoner's Dilemma Game

Science.gov (United States)

Canova, Gabriel A.; Arenzon, Jeferson J.

2017-09-01

When the interactions between cooperators (C) and defectors (D) can be partially avoided within a population, there may be an overall enhancement of cooperation. One example of such screening mechanism occurs in the presence of risk-averse agents (loners, L) that are neutral towards others, i.e., both L and its opponent, whatever its strategy, receive the same payoff. Their presence in the Prisoner's Dilemma (PD) game sustains the coexistence of cooperators and defectors far beyond the level attained in their absence. Another screening mechanism is a heterogeneous landscape obtained, for example, by site diluting the lattice. In this case, cooperation is enhanced with some fraction of such inactive, interaction-averse sites. By considering the interplay of both mechanisms, we show that there is an explosive increase in the range of densities, just above the percolation threshold, where neutrality is prevented and loners become extinct, the behavior reverting to the pure PD game. Interestingly, this occurs despite defectors being usually abundant in that region. This has to be compared with the corresponding loner-free region in the undiluted case that, besides being very small, is dominated by cooperators.

Mice infected with low-virulence strains of Toxoplasma gondii lose their innate aversion to cat urine, even after extensive parasite clearance.

Science.gov (United States)

Ingram, Wendy Marie; Goodrich, Leeanne M; Robey, Ellen A; Eisen, Michael B

2013-01-01

Toxoplasma gondii chronic infection in rodent secondary hosts has been reported to lead to a loss of innate, hard-wired fear toward cats, its primary host. However the generality of this response across T. gondii strains and the underlying mechanism for this pathogen-mediated behavioral change remain unknown. To begin exploring these questions, we evaluated the effects of infection with two previously uninvestigated isolates from the three major North American clonal lineages of T. gondii, Type III and an attenuated strain of Type I. Using an hour-long open field activity assay optimized for this purpose, we measured mouse aversion toward predator and non-predator urines. We show that loss of innate aversion of cat urine is a general trait caused by infection with any of the three major clonal lineages of parasite. Surprisingly, we found that infection with the attenuated Type I parasite results in sustained loss of aversion at times post infection when neither parasite nor ongoing brain inflammation were detectable. This suggests that T. gondii-mediated interruption of mouse innate aversion toward cat urine may occur during early acute infection in a permanent manner, not requiring persistence of parasite cysts or continuing brain inflammation.

Toxoplasma gondii influences aversive behaviors of female rats in an estrus cycle dependent manner.

Science.gov (United States)

Golcu, Doruk; Gebre, Rahiwa Z; Sapolsky, Robert M

2014-08-01

The protozoan Toxoplasma gondii (T. gondii) manipulates the behavior of its rodent intermediate host to facilitate its passage to its feline definitive host. This is accomplished by a reduction of the aversive response that rodents show towards cat odors, which likely increases the predation risk. Females on average show similar changes as males. However, behaviors that relate to aversion and attraction are usually strongly influenced by the estrus cycle. In this study, we replicated behavioral effects of T. gondii in female rats, as well as expanded it to two novel behavioral paradigms. We also characterized the role of the estrus cycle in the behavioral effects of T. gondii on female rats. Uninfected females preferred to spend more time in proximity to rabbit rather than bobcat urine, and in a dark chamber rather than a lit chamber. Infected females lost both of these preferences, and also spent more time investigating social novelty (foreign bedding in their environment). Taken together, these data suggest that infection makes females less risk averse and more exploratory. Furthermore, this effect was influenced by the estrus cycle. Uninfected rats preferred rabbit urine to bobcat urine throughout the cycle except at estrus and metestrus. In contrast, infected rats lost this preference at every stage of the cycle except estrus. Commensurate with the possibility that this was a hormone-dependent effect, infected rats had elevated levels of circulating progesterone, a known anxiolytic. Copyright © 2014 Elsevier Inc. All rights reserved.

Risk aversion and religious behaviour: Analysis using a sample of Danish twins.

Science.gov (United States)

Nielsen, Jytte Seested; Bech, Mickael; Christensen, Kaare; Kiil, Astrid; Hvidt, Niels Christian

2017-08-01

Economics offers an analytical framework to consider human behaviour including religious behaviour. Within the realm of Expected Utility Theory, religious belief and activity could be interpreted as an insurance both for current life events and for afterlife rewards. Based on that framework, we would expect that risk averse individuals would demand a more generous protection plan which they may do by devoting more effort and resources into religious activities such as church attendance and prayer, which seems to be in accordance with previous empirical results. However, a general concern regards the problems of spurious correlations due to underlying omitted or unobservable characteristics shaping both religious activities and risk attitudes. This paper examines empirically the demand for religion by analysing the association between risk attitudes on the one hand, and church attandance and prayer frequency on the other controlling for unobservable variables using survey data of Danish same-sex twin pairs. We verify the correlation between risk preferences and religion found previously by carrying out cross-sectional analyses. We also show that the association between risk attitudes and religious behaviour is driven by the subgroup of individuals who believe in an afterlife. In addition, when re-analysing our results using panel data analyses which cancel out shared factors among twin pairs, we find that the correlation found between risk aversion and religious behaviour is no longer significant indicating that other factors might explain differences in religious behaviour. Caution is needed in the interpretation of our results as the insignificant association between risk aversion and religious behaviour in the panel data analyses potentially might be due to measurement error causing attenuation bias or lack of variation within twin pairs rather than the actual absence of an association. Copyright © 2017 Elsevier B.V. All rights reserved.

An ordinal approach to computing with words and the preference-aversion model

DEFF Research Database (Denmark)

Franco de los Rios, Camilo Andres; Rodríguez, J. Tinguaro; Montero, Javier

2014-01-01

Computing with words (CWW) explores the brain’s ability to handle and evaluate perceptions through language, i.e., by means of the linguistic representation of information and knowledge. On the other hand, standard preference structures examine decision problems through the decomposition of the p......Computing with words (CWW) explores the brain’s ability to handle and evaluate perceptions through language, i.e., by means of the linguistic representation of information and knowledge. On the other hand, standard preference structures examine decision problems through the decomposition...... of the preference predicate into the simpler situations of strict preference, indifference and incomparability. Hence, following the distinctive cognitive/neurological features for perceiving positive and negative stimuli in separate regions of the brain, we consider two separate and opposite poles of preference...... and aversion, and obtain an extended preference structure named the Preference–aversion (P–A) structure. In this way, examining the meaning of words under an ordinal scale and using CWW’s methodology, we are able to formulate the P–A model under a simple and purely linguistic approach to decision making...

Modelling risk aversion to support decision-making for controlling zoonotic livestock diseases.

Science.gov (United States)

van Asseldonk, M A P M; Bergevoet, R H M; Ge, L

2013-12-01

Zoonotic infectious livestock diseases are becoming a significant burden for both animal and human health and are rapidly gaining the attention of decision-makers who manage public health programmes. If control decisions have only monetary components, governments are generally regarded as being risk-neutral and the intervention strategy with the highest expected benefit (lowest expected net costs) should be preferred. However, preferences will differ and alternative intervention plans will prevail if (human) life and death outcomes are involved. A rational decision framework must therefore consider risk aversion in the decision-maker and controversial values related to public health. In the present study, risk aversion and its impact on both the utility for the monetary component and the utility for the non-monetary component is shown to be an important element when dealing with emerging zoonotic infectious livestock diseases and should not be ignored in the understanding and support of decision-making. The decision framework was applied to several control strategies for the reduction of human cases of brucellosis (Brucella melitensis) originating from sheep in Turkey.

Testing taste sensitivity and aversion in very young children : development of a procedure

NARCIS (Netherlands)

Visser, J; Kroeze, J.H.A.; Kamps, WA; Bijleveld, CMA

Taste perception in 45 3- to 6-year-old children was tested using procedures specifically designed for this age group. Detection thresholds for sucrose and urea were measured by a staircase method and aversion to urea was assessed hedonically, using drawings of facial expressions. All children

Imagery rescripting : The impact of conceptual and perceptual changes on aversive autobiographical memories

NARCIS (Netherlands)

Slofstra, Christien; Nauta, Maaike H.; Holmes, Emily A.; Bockting, C. L. H.

2016-01-01

BACKGROUND: Imagery rescripting (ImRs) is a process by which aversive autobiographical memories are rendered less unpleasant or emotional. ImRs is thought only to be effective if a change in the meaning-relevant (semantic) content of the mental image is produced, according to a cognitive hypothesis

A high-protein diet enhances satiety without conditioned taste aversion in the rat.

Science.gov (United States)

Bensaïd, Ahmed; Tomé, Daniel; L'Heureux-Bourdon, Diane; Even, Patrick; Gietzen, Dorothy; Morens, Céline; Gaudichon, Claire; Larue-Achagiotis, Christiane; Fromentin, Gilles

2003-02-01

In order to determine the respective roles of conditioned food aversion, satiety and palatability, we studied behavioral responses to a 50% total milk protein diet, compared with those to a normal protein diet containing 14% total milk protein. Different paradigms were employed, including meal pattern analysis, two-choice testing, flavor testing, a behavioral satiety sequence (BSS) and taste reactivity. Our experiments showed that only behavioral and food intake parameters were disturbed during the first day when an animal ate the high-protein (P50) diet, and that most parameters returned to baseline values as soon as the second day of P50. Rats adapted to P50 did not acquire a conditioned taste aversion (CTA) but exhibited satiety, and a normal BSS. The initial reduction in high-protein diet intake appeared to result from the lower palatability of the food combined with the satiety effect of the high-protein diet and the delay required for metabolic adaptation to the higher protein level.

A direct comparison of appetitive and aversive anticipation: Overlapping and distinct neural activation.

Science.gov (United States)

Sege, Christopher T; Bradley, Margaret M; Weymar, Mathias; Lang, Peter J

2017-05-30

fMRI studies of reward find increased neural activity in ventral striatum and medial prefrontal cortex (mPFC), whereas other regions, including the dorsolateral prefrontal cortex (dlPFC), anterior cingulate cortex (ACC), and anterior insula, are activated when anticipating aversive exposure. Although these data suggest differential activation during anticipation of pleasant or of unpleasant exposure, they also arise in the context of different paradigms (e.g., preparation for reward vs. threat of shock) and participants. To determine overlapping and unique regions active during emotional anticipation, we compared neural activity during anticipation of pleasant or unpleasant exposure in the same participants. Cues signalled the upcoming presentation of erotic/romantic, violent, or everyday pictures while BOLD activity during the 9-s anticipatory period was measured using fMRI. Ventral striatum and a ventral mPFC subregion were activated when anticipating pleasant, but not unpleasant or neutral, pictures, whereas activation in other regions was enhanced when anticipating appetitive or aversive scenes. Copyright © 2017 Elsevier B.V. All rights reserved.

Induction of aversive learning through thermogenetic activation of Kenyon cell ensembles in Drosophila

Directory of Open Access Journals (Sweden)

David eVasmer

2014-05-01

Full Text Available Drosophila represents a model organism to analyze neuronal mechanisms underlying learning and memory. Kenyon cells of the Drosophila mushroom body are required for associative odor learning and memory retrieval. But is the mushroom body sufficient to acquire and retrieve an associative memory? To answer this question we have conceived an experimental approach to bypass olfactory sensory input and to thermogenetically activate sparse and random ensembles of Kenyon cells directly. We found that if the artifical activation of Kenyon cell ensembles coincides with a salient, aversive stimulus learning was induced The animals adjusted their behavior in a subsequent test situation and actively avoided reactivation of these Kenyon cells. Our results show that Kenyon cell activity in coincidence with a salient aversive stimulus can suffice to form an associative memory. Memory retrieval is characterized by a closed feedback loop between a behavioral action and the reactivation of sparse ensembles of Kenyon cells.

Aversive workplace conditions and absenteeism : Taking referent group norms and supervisor support into account

NARCIS (Netherlands)

Biron, M.; Bamberger, P.

2012-01-01

Past research reveals inconsistent findings regarding the association between aversive workplace conditions and absenteeism, suggesting that other, contextual factors may play a role in this association. Extending contemporary models of absence, we draw from the social identity theory of

[Acceptance and Commitment Therapy in the Treatment of Chronic Disease].

Science.gov (United States)

Kuba, Katharina; Weißflog, Gregor

2017-12-01

Acceptance and Commitment Therapy (ACT) is an intervention representing a transdiagnostic and contextual approach that assumes that psychological suffering is caused by experiential avoidance. The primary intention of ACT is not to eliminate symptoms and to treat mental disorders. Instead, ACT aims to increase psychological flexibility, i. e. to broaden the repertoire of cognitions and behaviors when facing inner and outer aversive events or experiences. Psychological flexibility can be enhanced by working with the 6 core components of the ACT model. Experience-focused methods like metaphors and exercises for acceptance play a crucial role in the therapeutic work. In short, with ACT patients can learn: ▪ that rigid and inflexible attempts to fight aversive experience are problematic ▪ a mindful experience of inner and outer experience ▪ to differentiate between unchangeable and changeable events (acceptance) ▪ to identify values or respectively life goals and to behave in a way that is consistent with them (commitment)The therapeutic focus of ACT is to create a balance between acceptance and behavioral change consistent with chosen values. Chronic diseases are often associated with aversive inner and outer experiences. A growing number of studies support the efficacy of ACT. There is evidence that ACT can increase psychological flexibility and potentially also lead to better self-management within the context of chronic somatic diseases. © Georg Thieme Verlag KG Stuttgart · New York.

Simulating the market coefficient of relative risk aversion

Directory of Open Access Journals (Sweden)

Samih Antoine Azar

2014-12-01

Full Text Available In this paper, expected utility, defined by a Taylor series expansion around expected wealth, is maximized. The coefficient of relative risk aversion (CRRA that is commensurate with a 100% investment in the risky asset is simulated. The following parameters are varied: the riskless return, the market standard deviation, the market stock premium, and the skewness and the kurtosis of the risky return. Both the high extremes and the low extremes are considered. With these figures, the upper bound of the market CRRA is 3.021 and the lower bound is 0.466. Log utility, which corresponds to a CRRA of 1, is not excluded.

Gaze Aversion during Social Style Interactions in Autism Spectrum Disorder and Williams Syndrome

Science.gov (United States)

Doherty-Sneddon, Gwyneth; Whittle, Lisa; Riby, Deborah M.

2013-01-01

During face-to-face interactions typically developing individuals use gaze aversion (GA), away from their questioner, when thinking. GA is also used when individuals with autism (ASD) and Williams syndrome (WS) are thinking during question-answer interactions. We investigated GA strategies during face-to-face social style interactions with…

Conditioned food aversion to control poisoning by Ipomoea carnea subsp. fistulosa in goats

Science.gov (United States)

Ipomoea carnea is a toxic plant often ingested by livestock in Brazil. Three experiments were conducted to determine if conditioned food aversion was effective in reducing goats’ consumption of I. carnea. In the fi rst experiment, 10 mildly intoxicated goats that had been eating I. carnea were avert...