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Sample records for reported contingent aversive

  1. 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

  2. Rapid prefrontal cortex activation towards aversively paired faces and enhanced contingency detection are observed in highly trait-anxious women under challenging conditions

    Directory of Open Access Journals (Sweden)

    Maimu Alissa Rehbein

    2015-06-01

    Full Text Available Relative to healthy controls, anxiety-disorder patients show anomalies in classical conditioning that may either result from, or provide a risk factor for, clinically relevant anxiety. Here, we investigated whether healthy participants with enhanced anxiety vulnerability show abnormalities in a challenging affective-conditioning paradigm, in which many stimulus-reinforcer associations had to be acquired with only few learning trials. Forty-seven high and low trait-anxious females underwent MultiCS conditioning, in which 52 different neutral faces (CS+ were paired with an aversive noise (US, while further 52 faces (CS- remained unpaired. Emotional learning was assessed by evaluative (rating, behavioral (dot-probe, contingency report, and neurophysiological (magnetoencephalography measures before, during, and after learning. High and low trait-anxious groups did not differ in evaluative ratings or response priming before or after conditioning. High trait-anxious women, however, were better than low trait-anxious women at reporting CS+/US contingencies after conditioning, and showed an enhanced prefrontal cortex activation towards CS+ in the M1 (i.e., 80 to 117 ms and M170 time intervals (i.e., 140 to 160 ms during acquisition. These effects in MultiCS conditioning observed in individuals with elevated trait anxiety are consistent with theories of enhanced conditionability in anxiety vulnerability. Furthermore, they point towards increased threat monitoring and detection in highly trait-anxious females, possibly mediated by alterations in visual working memory.

  3. Oceania regional contingency plan. Draft report

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-30

    The Plan is a Regional Contingency Plan (RCP) for USEPA Region IX - Oceania which includes the State of Hawaii, Commonwealth of the Northern Marianas Islands, Territory of Guam and Territory of American Samoa as well as all other islands under U.S. jurisdiction in the south and central Pacific Ocean. It reflects updates and revisions to the Oceania Plan developed by the U.S. Coast Guard (USCG). The individual sub-Area plans address areas of environmental or special economic importance. Environmentally sensitive areas are broadly defined to include unique or pristine areas, critical or endangered wildlife species habitats, National, state or local parks, fish hatcheries, shore areas, and research, cultural or archaeological sites. Due to the scope and detail required to identify these areas, drinking water intakes and environmentally sensitive areas will be covered in the specific sub-Area plans.

  4. Contingency Contractor Optimization Phase 3 Sustainment Verification and Validation V&V) Report - Contingency Contractor Optimization Engineering - Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Bandlow, Alisa [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Operations Research and Computational Analysis; Durfee, Justin David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Operations Research and Computational Analysis; Frazier, Christopher Rawls [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Operations Research and Computational Analysis; Gearhart, Jared Lee [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Operations Research and Computational Analysis; Jones, Katherine A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Operations Research and Computational Analysis; Adair, Kristin Lynn [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Operations Research and Computational Analysis; Turgeon, Jennifer [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). High Confidence System Environments

    2016-04-01

    The reports and test plans contained within this document serve as supporting materials to the activities listed within the “Contingency Contractor Optimization Tool – Prototype (CCOT-P) Verification & Validation Plan” [1]. The activities included test development, testing, peer reviews, and expert reviews. The engineering prototype reviews were done for both the software and the mathematical model used in CCOT-P. Section 2 includes the peer and expert review reports, which summarize the findings from each of the reviews and document the resolution of any issues. Section 3 details the test plans that were followed for functional testing of the application through the interface. Section 4 describes the unit tests that were run on the code.

  5. Idaho National Engineering Laboratory Environmental Restoration Program Schedule Contingency Evaluation Report

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    This report represents the schedule contingency evaluation done on the FY-93 Major System Acquisition (MSA) Baseline for the Idaho National Engineering Laboratory`s (INEL) Environmental Restoration Program (EPP). A Schedule Contingency Evaluation Team (SCET) was established to evaluate schedule contingency on the MSA Baseline for the INEL ERP associated with completing work within milestones established in the baseline. Baseline schedules had been established considering enforceable deadlines contained in the Federal Facilities Agreement/Consent Order (FFA/CO), the agreement signed in 1992, by the State of Idaho, Department of Health & Welfare, the U.S. Environmental Protection Agency, Region 10, and the U.S. Department of Energy, Idaho Operations Office. The evaluation was based upon the application of standard schedule risk management techniques to the specific problems of the INEL ERP. The schedule contingency evaluation was designed to provided early visibility for potential schedule delays impacting enforceable deadlines. The focus of the analysis was on the duration of time needed to accomplish all required activities to achieve completion of the milestones in the baseline corresponding to the enforceable deadlines. Additionally, the analysis was designed to identify control of high-probability, high-impact schedule risk factors.

  6. 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.

  7. Reconciling the role of serotonin in behavioral inhibition and aversion: acute tryptophan depletion abolishes punishment-induced inhibition in humans.

    Science.gov (United States)

    Crockett, Molly J; Clark, Luke; Robbins, Trevor W

    2009-09-23

    The neuromodulator serotonin has been implicated in a large number of affective and executive functions, but its precise contribution to motivation remains unclear. One influential hypothesis has implicated serotonin in aversive processing; another has proposed a more general role for serotonin in behavioral inhibition. Because behavioral inhibition is a prepotent reaction to aversive outcomes, it has been a challenge to reconcile these two accounts. Here, we show that serotonin is critical for punishment-induced inhibition but not overall motor response inhibition or reporting aversive outcomes. We used acute tryptophan depletion to temporarily lower brain serotonin in healthy human volunteers as they completed a novel task designed to obtain separate measures of motor response inhibition, punishment-induced inhibition, and sensitivity to aversive outcomes. After a placebo treatment, participants were slower to respond under punishment conditions compared with reward conditions. Tryptophan depletion abolished this punishment-induced inhibition without affecting overall motor response inhibition or the ability to adjust response bias in line with punishment contingencies. The magnitude of reduction in punishment-induced inhibition depended on the degree to which tryptophan depletion reduced plasma tryptophan levels. These findings extend and clarify previous research on the role of serotonin in aversive processing and behavioral inhibition and fit with current theorizing on the involvement of serotonin in predicting aversive outcomes.

  8. Contingent workers.

    Science.gov (United States)

    Guerrina, Ryan T; Burns, Candace M; Conlon, Helen

    2011-03-01

    Contingent workers compose a large portion of the U.S. work force. Contingent workers include temporary employees, contracted employees, day laborers, and freelancers. The skill level and educational requirements for their jobs vary from basic to highly advanced. Construction, housekeeping, engineering, and nursing have such positions. U.S. contingent workers are more likely to engage in occupations associated with increased risk of injury, and a variety of factors increase their risk of work injuries, particularly those leading to death. This article focuses on select occupational health and safety issues affecting contingent workers and their implications for occupational health nurses. Copyright 2011, SLACK Incorporated.

  9. The Effect of Contingent Reinforcement on the Acquisition of Sight Vocabulary. Technical Report No. 49.

    Science.gov (United States)

    Brandt, Mary E.; And Others

    The present study is a replication of a Lahey and Drabman study (1974) which investigated the effects of contingent versus noncontingent reinforcement on the learning of sight words. The subjects in this study were 14 Kamehameha Early Education Program (KEEP) students who composed the lowest reading group in a combined first-second grade…

  10. 75 FR 27464 - Special Reporting, Analysis and Contingent Resolution Plans at Certain Large Insured Depository...

    Science.gov (United States)

    2010-05-17

    ... complex financial parent companies to submit to the FDIC analysis, information, and contingent resolution... IDIs with greater than $10 billion in total assets that are owned or controlled by parent companies... that exist within even larger conglomerate and multinational structures. These large and complex IDIs...

  11. Future Contingents

    DEFF Research Database (Denmark)

    Øhrstrøm, Peter; Hasle., Per F. V.

    2015-01-01

    will be a sea-battle tomorrow” could serve as standard examples. What could be called the problem of future contingents concerns how to ascribe truth-values to such statements. If there are several possible decisions out of which one is going to be made freely tomorrow, can there be a truth now about which one......, ‘future contingents’ could also refer to future contingent objects. A statement like “The first astronaut to go to Mars will have a unique experience” could be analyzed as referring to an object not yet existing, supposing that one day in the distant future some person will indeed travel to Mars......, but that person has not yet been born. The notion of ‘future contingent objects’ involves important philosophical questions, for instance the issue of ethical obligations towards future generations, quantification over ‘future contingent objects’ etc. However, this entry is confined to the study of future...

  12. Future Contingents

    DEFF Research Database (Denmark)

    Øhrstrøm, Peter; Hasle., Per F. V.

    2011-01-01

    will be a sea-battle tomorrow” could serve as standard examples. What could be called the problem of future contingents concerns how to ascribe truth-values to such statements. If there are several possible decisions out of which one is going to be made freely tomorrow, can there be a truth now about which one......, ‘future contingents’ could also refer to future contingent objects. A statement like “The first astronaut to go to Mars will have a unique experience” could be analyzed as referring to an object not yet existing, supposing that one day in the distant future some person will indeed travel to Mars......, but that person has not yet been born. The notion of ‘future contingent objects’ involves important philosophical questions, for instance the issue of ethical obligations towards future generations, quantification over ‘future contingent objects’ etc. However, this entry is confined to the study of future...

  13. Classification errors in contingency tables analyzed with hierarchical log-linear models. Technical report No. 20

    Energy Technology Data Exchange (ETDEWEB)

    Korn, E L

    1978-08-01

    This thesis is concerned with the effect of classification error on contingency tables being analyzed with hierarchical log-linear models (independence in an I x J table is a particular hierarchical log-linear model). Hierarchical log-linear models provide a concise way of describing independence and partial independences between the different dimensions of a contingency table. The structure of classification errors on contingency tables that will be used throughout is defined. This structure is a generalization of Bross' model, but here attention is paid to the different possible ways a contingency table can be sampled. Hierarchical log-linear models and the effect of misclassification on them are described. Some models, such as independence in an I x J table, are preserved by misclassification, i.e., the presence of classification error will not change the fact that a specific table belongs to that model. Other models are not preserved by misclassification; this implies that the usual tests to see if a sampled table belong to that model will not be of the right significance level. A simple criterion will be given to determine which hierarchical log-linear models are preserved by misclassification. Maximum likelihood theory is used to perform log-linear model analysis in the presence of known misclassification probabilities. It will be shown that the Pitman asymptotic power of tests between different hierarchical log-linear models is reduced because of the misclassification. A general expression will be given for the increase in sample size necessary to compensate for this loss of power and some specific cases will be examined.

  14. 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....

  15. 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....

  16. Contingency Theories of Leadership: A Study.

    Science.gov (United States)

    Saha, Sunhir K.

    1979-01-01

    Some of the major contingency theories of leadership are reviewed; some results from the author's study of Fiedler's contingency model are reported; and some thoughts for the future of leadership research are provided. (Author/MLF)

  17. Some aversive characteristics of centrifugally generated gravity.

    Science.gov (United States)

    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.

  18. 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.

  19. Investigation of anabolic steroids in two taste aversion paradigms.

    Science.gov (United States)

    Ganesan, R; Rosellini, R A; Svare, B

    1993-02-01

    The aversive effects of estradiol have been studied in two different taste aversion paradigms. A similar investigation was undertaken for the anabolic-androgenic steroids, nandralone and testosterone cypionate, using Rockland-Swiss mice. Experiments 1 and 2 used the brief exposure of a novel saccharin solution as the conditioned stimulus for taste aversion learning, and showed that anabolic steroids (1 mg) do not induce taste aversions. Instead, these hormones induced a small non-contingent increase in saccharin preference. Experiment 3 showed that daily nandralone administration (1 mg/day) had a greater anabolic effect than the same dose of testosterone cypionate. Experiment 4 paired the continuous exposure to a novel diet with daily nandralone injections, and showed that steroid treatment increased intake of the novel diet. When the novel diet was subsequently presented with the familiar diet in a two-choice preference test, there was no indication that an aversion was conditioned to the novel target diet. On the contrary, nandralone treatment significantly increased the preference for the novel diet. These experiments show that anabolic-androgenic steroids do not have aversive effects in mice, and that they may have positive consequences.

  20. Loss Aversion and Individual Characteristics

    DEFF Research Database (Denmark)

    Hjorth, Katrine; Fosgerau, Mogens

    2011-01-01

    Many studies have shown that loss aversion affects the valuation of non-market goods. Using stated choice data, this paper presents an empirical investigation of how individual-level loss aversion varies with observable personal characteristics and with the choice context. We investigate loss...... aversion with respect to travel time and money, and find significant loss aversion in both dimensions. The degree of loss aversion in the time dimension is larger than in the money dimension, and depends on age and education. Subjects tend to be more loss averse when the reference is well established....

  1. Activation of Dopamine Neurons is Critical for Aversive Conditioning and Prevention of Generalized Anxiety

    OpenAIRE

    2011-01-01

    Generalized anxiety is thought to result, in part, from impairments in contingency awareness during conditioning to cues that predict aversive or fearful outcomes. Dopamine neurons of the ventral midbrain exhibit heterogeneous responses to aversive stimuli that are thought to provide a critical modulatory signal to facilitate orienting to environmental changes and assignment of motivational value to unexpected events. Here, we describe a mouse model in which activation of dopamine neurons in ...

  2. Future Contingents

    DEFF Research Database (Denmark)

    Øhrstrøm, Peter; Hasle., Per F. V.

    2011-01-01

    will be a sea-battle tomorrow” could serve as standard examples. What could be called the problem of future contingents concerns how to ascribe truth-values to such statements. If there are several possible decisions out of which one is going to be made freely tomorrow, can there be a truth now about which one...... about the future. Finally, it should be mentioned that temporal logic has found a remarkable application in computer science and applied mathematics. In the late 1970s the first computer scientists realised the relevance of temporal logic for the purposes of computer science (see Hasle and Øhrstrøm 2004)....

  3. ACCOUNTING OF PROVISIONS, CONTINGENT LIABILITIES, CONTINGENT ASSETS IN SCOPE OF IAS 37

    OpenAIRE

    Usul, Hayrettin; ÖZER KEÇE, Figen

    2016-01-01

    This study tries to gain an insight into thenumber 37 Provisions, Contingent Liabilities and Contingent Assets, one of theInternational Financial Reporting Standards. At first a general overview hasbeen provided about these concepts, and then under what circumstancesbusinesses accrue provisions, contingent liabilities and contingent assets andwhat kind of information related to the concepts about financial statementsshould be explained have been examined in detail. After these explanations, i...

  4. 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.

  5. Secret Sauce and Snake Oil: Writing Monthly Reports in a Highly Contingent Environment

    Science.gov (United States)

    Spinuzzi, Clay

    2010-01-01

    At a search marketing company, each search engine optimization (SEO) specialist writes up to 10 to 12 complex 20-page monthly reports in the first ten business days of each month. These SEO specialists do not consider themselves to be writers, yet they generate these structurally and rhetorically complex reports as a matter of course, while…

  6. Secret Sauce and Snake Oil: Writing Monthly Reports in a Highly Contingent Environment

    Science.gov (United States)

    Spinuzzi, Clay

    2010-01-01

    At a search marketing company, each search engine optimization (SEO) specialist writes up to 10 to 12 complex 20-page monthly reports in the first ten business days of each month. These SEO specialists do not consider themselves to be writers, yet they generate these structurally and rhetorically complex reports as a matter of course, while…

  7. 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...

  8. A note on testing guilt aversion

    NARCIS (Netherlands)

    Bellemare, C.; Sebald, A.; Suetens, Sigrid

    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

  9. Brief light as a practical aversive stimulus for the albino rat.

    Science.gov (United States)

    Barker, David J; Sanabria, Federico; Lasswell, Anne; Thrailkill, Eric A; Pawlak, Anthony P; Killeen, Peter R

    2010-12-25

    Bright light was an effective aversive stimulus for Wistar rats in punishment, escape, and avoidance paradigms. Contingent punishment of lever pressing maintained by concurrent schedules of food delivery shifted presses to an alternate lever, and depressed overall response rates. Periodic non-contingent presentation of the light prompted escape responding (head entry into a hole). Unsignaled avoidance contingencies were not effective, but pre-pulse signaling of light supported avoidance behavior. These results demonstrate a possible alternative to foot-shock, one with greater ecological validity, and one that might avoid some of the physiological effects that accompany electric shock. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  10. Shirking, Monitoring, and Risk Aversion

    OpenAIRE

    2014-01-01

    This paper studies the effect of risk aversion on effort under different monitoring schemes. It uses a theoretical model which relaxes the assumption of agents being risk neutral, and investigates changes of effort as monitoring varies. The predictions of the theoretical model are tested using an original experimental setting where the level of risk aversion is measured and monitoring rates vary exogenously. Our results show that shirking decreases with risk aversion, being female, and monito...

  11. Morning sickness and salt intake, food cravings, and food aversions.

    Science.gov (United States)

    Crystal, S R; Bowen, D J; Bernstein, I L

    1999-08-01

    Evidence for an association between early pregnancy sickness and offspring salt (NaCl) preference has been obtained from studying offspring as young adults and as infants. To determine whether the association between early pregnancy sickness and salt preference of offspring is secondary to familiar similarity in salt preference, the present study examined the self-reported salt intake and dietary cravings and aversions of pregnant women. Women who reported little or no vomiting (n = 108) were compared to women who reported moderate to severe vomiting (n = 21) during pregnancy. The women's self-reported salt use and reported cravings and aversions for common food were measured via survey for time periods prior to and during their current pregnancy. Women did not differ in reported salt use prior to pregnancy as a function of their pregnancy symptoms. Women reported more aversions during, than prior to, pregnancy (p < 0.05). Women with more severe vomiting reported a greater number of aversions (p < 0.05) both prior to and during pregnancy. There was a significant association between experiencing cravings and aversions prior to pregnancy and experiencing craving and aversions during pregnancy (p < 0.05). These findings do not provide evidence for an association between dietary levels of sodium and the likelihood of experiencing severe pregnancy symptoms. Therefore, these data do not support the suggestion that reported elevations in salt preference in offspring of women with moderate to severe vomiting during pregnancy are mediated by familial dietary practices.

  12. Contingent Commitments: Bringing Part-Time Faculty into Focus. A Special Report from the Center for Community College Student Engagement

    Science.gov (United States)

    Center for Community College Student Engagement, 2014

    2014-01-01

    Part-time faculty teach approximately 58% of U.S. community college classes and thus manage learning experiences for more than half (53%) of students enrolled in community colleges (JBL Associates, 2008). Often referred to as "contingent faculty," their work is conditional; the college typically has no obligation to them beyond the…

  13. 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

  14. Alcohol reduces aversion to ambiguity

    Science.gov (United States)

    Tyszka, Tadeusz; Macko, Anna; Stańczak, Maciej

    2015-01-01

    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. PMID:25642202

  15. 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.

  16. Oil spill contingency planning

    Energy Technology Data Exchange (ETDEWEB)

    Kip, S.H. (Sarawak Shell Bhd/Saban Shell Petroleum Co. Ltd. (MY))

    1988-01-01

    Oil spill contingency planning is an essential feature required in present day activities involving oil and gas exploration, production and transportation. A well through out continency plan will not only eliminate or minimize the sense of panic, normally associated with oil spill emergency, but also can minimize damage and cost involved. Oil spill contingency planning is a process of predetermining a response to an oil spill emergency. The process of preparing a contingency plan is discussed in this paper.

  17. Acquisition of CS-US contingencies during Pavlovian fear conditioning and extinction in social anxiety disorder and posttraumatic stress disorder.

    Science.gov (United States)

    Rabinak, Christine A; Mori, Shoko; Lyons, Maryssa; Milad, Mohammed R; Phan, K Luan

    2017-01-01

    Fear-based disorders, like social anxiety disorder (SAD) and posttraumatic stress disorder (PTSD), are characterized by an exaggerated fear response and avoidance to trigger cues, suggesting a transdiagnostic mechanism of psychopathology. Current theories suggest that abnormalities in conditioned fear is a primary contributor to the pathophysiology of these disorders. The primary goal of this study was to compare acquisition of conditioned stimulus (CS) and aversive unconditioned stimulus (US) contingencies during fear learning and extinction in individuals with SAD and PTSD. In a standard Pavlovian fear conditioning-extinction paradigm we measured subjective US expectancy ratings to different CSs in patients with SAD (n=16) compared to patients with PTSD (n=13) and healthy controls (n=15) RESULTS: Both patient groups (SAD, PTSD) acquired differential conditioning between a CS that predicted US (CS+) and a CS that never predicted the US (CS-), however, both groups reported an increased expectancy that the US would occur following the CS-. Additionally, the PTSD group overestimated that the US would occur in general. Neither patient group showed evidence of successful extinction of the CS+-US contingency nor differentiated their expectation of US occurrence between the CS+ and CS- during extinction learning. Group sample sizes were small and we did not include a trauma-exposed group without PTSD CONCLUSIONS: Both SAD and PTSD generalize expectations of an aversive outcome across CSs, even when a CS never signals an aversive outcome and PTSD may tend to over-expect threat. Fear learning and extinction abnormalities may be a core feature underlying shared symptoms across fear-based disorders. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Aversive smell associations shape social judgment.

    Science.gov (United States)

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

    2017-10-01

    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 with the smell-conditioned face (without any smell), the participants tended to judge both positive and negative behaviors as indicative of personality traits rather than related to the situation. This effect was predicted by the degree of the preceding olfactory evaluative conditioning. Whole brain analysis of stimulus by stage interaction indicated differential activation of the ventromedial prefrontal cortex and right angular gyrus to the conditioned versus the neutral person during the attribution phase only. These results suggest that negative smell associations do not simply induce a negative perception of the target person but rather bias the attribution style towards trait attributions. The fact that this bias was evident regardless of behavior valence suggests it may reflect enhanced psychological distance. Thus, the known observation of social rejection triggered by aversive smell may be driven by a shift in social attribution style. Copyright © 2017 Elsevier Inc. All rights reserved.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  20. Enhancing the Expression of Flavor Neophobia: Some Effects of the Ingestion-Illness Contingency

    Science.gov (United States)

    Best, Michael R.; Batson, John D.

    1977-01-01

    These experiments investigate the degree to which neophobia, the reluctance to consume novel food, can be modified by toxicosis, the conditions under which the contingency between ingestion and illness enhances neophobia, and the manner in which previously learned aversions mediate subsequent enhanced neophobia. (Author/RK)

  1. Lying aversion and prosocial behaviour

    CERN Document Server

    Biziou-van-Pol, Laura; Novaro, Arianna; Liberman, Andrés Occhipinti; Capraro, Valerio

    2015-01-01

    The focus of this paper is the moral conflict between lying aversion and prosociality. What does telling a white lie signal about a person's prosocial tendencies? How does believing a possibly untruthful message signal about a listener's prosocial tendencies? To answer these questions, we conducted a 2x3 experiment. In the first stage we measured altruistic tendencies using a Dictator Game and cooperative tendencies using a Prisoner's dilemma. In the second stage, we used a sender-receiver game to measure aversion to telling a Pareto white lie (i.e., a lie that helps both the liar and the listener), aversion to telling an altruistic white lie (i.e., a lie that helps the listener at the expense of the liar), and skepticism towards believing a possibly untruthful message. We found three major results: (i) both altruism and cooperation are positively correlated with aversion to telling a Pareto white lie; (ii) neither altruism nor cooperation are significantly correlated with aversion to telling an altruistic wh...

  2. An examination of ambiguity aversion

    Directory of Open Access Journals (Sweden)

    L. Robin Keller

    2007-12-01

    Full Text Available Ambiguity aversion has been widely observed in individuals' judgments. Using scenarios that are typical in decision analysis, we investigate ambiguity aversion for pairs of individuals. We examine risky and cautious shifts from individuals' original judgments to their judgments when they are paired up in dyads. In our experiment the participants were first asked to specify individually their willingness-to-pay for six monetary gambles. They were then paired at random into dyads, and were asked to specify their willingness-to-pay amount for the same gambles. The dyad's willingness-to-pay amount was to be shared equally by the two individuals. Of the six gambles in our experiment, one involved no ambiguity and the remaining five involved different degrees of ambiguity. We found that dyads exhibited risk aversion as well as ambiguity aversion. The majority of the dyads exhibited a cautious shift in the face of ambiguity, stating a smaller willingness-to-pay than the two individuals' average. Our study thus confirms the persistence of ambiguity aversion in a group setting and demonstrates the predominance of cautious shifts for dyads.

  3. Parallel contingency statistics with Titan.

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, David C.; Pebay, Philippe Pierre

    2009-09-01

    This report summarizes existing statistical engines in VTK/Titan and presents the recently parallelized contingency statistics engine. It is a sequel to [PT08] and [BPRT09] which studied the parallel descriptive, correlative, multi-correlative, and principal component analysis engines. The ease of use of this new parallel engines is illustrated by the means of C++ code snippets. Furthermore, this report justifies the design of these engines with parallel scalability in mind; however, the very nature of contingency tables prevent this new engine from exhibiting optimal parallel speed-up as the aforementioned engines do. This report therefore discusses the design trade-offs we made and study performance with up to 200 processors.

  4. Contingency planning: preparation of contingency plans

    DEFF Research Database (Denmark)

    Westergaard, J M

    2008-01-01

    . The risk of introducing disease pathogens into a country and the spread of the agent within a country depends on a number of factors including import controls, movement of animals and animal products and the biosecurity applied by livestock producers. An adequate contingency plan is an important instrument...

  5. Coordinated activity of ventral tegmental neurons adapts to appetitive and aversive learning.

    Directory of Open Access Journals (Sweden)

    Yunbok Kim

    Full Text Available Our understanding of how value-related information is encoded in the ventral tegmental area (VTA is based mainly on the responses of individual putative dopamine neurons. In contrast to cortical areas, the nature of coordinated interactions between groups of VTA neurons during motivated behavior is largely unknown. These interactions can strongly affect information processing, highlighting the importance of investigating network level activity. We recorded the activity of multiple single units and local field potentials (LFP in the VTA during a task in which rats learned to associate novel stimuli with different outcomes. We found that coordinated activity of VTA units with either putative dopamine or GABA waveforms was influenced differently by rewarding versus aversive outcomes. Specifically, after learning, stimuli paired with a rewarding outcome increased the correlation in activity levels between unit pairs whereas stimuli paired with an aversive outcome decreased the correlation. Paired single unit responses also became more redundant after learning. These response patterns flexibly tracked the reversal of contingencies, suggesting that learning is associated with changing correlations and enhanced functional connectivity between VTA neurons. Analysis of LFP recorded simultaneously with unit activity showed an increase in the power of theta oscillations when stimuli predicted reward but not an aversive outcome. With learning, a higher proportion of putative GABA units were phase locked to the theta oscillations than putative dopamine units. These patterns also adapted when task contingencies were changed. Taken together, these data demonstrate that VTA neurons organize flexibly as functional networks to support appetitive and aversive learning.

  6. 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

  7. 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 los

  8. 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

  9. Ambiguity aversion in rhesus macaques

    Directory of Open Access Journals (Sweden)

    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.

  10. 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…

  11. 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 ...

  12. Waterfowl disease contingency plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this contingency plan is reduce waterfowl losses from disease, primarily avian botulism, along the eastern shore of the Great Salt Lake in Utah. This...

  13. Contingent Information Systems Development

    NARCIS (Netherlands)

    van Slooten, C.; Schoonhoven, Bram

    1996-01-01

    Situated approaches based on project contingencies are becoming more and more an important research topic for information systems development organizations. The Information Services Organization, which was investigated, has recognized that it should tune its systems development approaches to the

  14. 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.

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

    Directory of Open Access Journals (Sweden)

    Yusuke eTanaka

    2015-02-01

    Full Text Available 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 in clinical psychology. Cautious applications of decision theory to clinical neuropsychiatry are recommended.

  16. Global Health, Geographical Contingency, and Contingent Geographies

    Science.gov (United States)

    Herrick, Clare

    2016-01-01

    Health geography has emerged from under the “shadow of the medical” to become one of the most vibrant of all the subdisciplines. Yet, this success has also meant that health research has become increasingly siloed within this subdisciplinary domain. As this article explores, this represents a potential lost opportunity with regard to the study of global health, which has instead come to be dominated by anthropology and political science. Chief among the former's concerns are exploring the gap between the programmatic intentions of global health and the unintended or unanticipated consequences of their deployment. This article asserts that recent work on contingency within geography offers significant conceptual potential for examining this gap. It therefore uses the example of alcohol taxation in Botswana, an emergent global health target and tool, to explore how geographical contingency and the emergent, contingent geographies that result might help counter the prevailing tendency for geography to be side-stepped within critical studies of global health. At the very least, then, this intervention aims to encourage reflection by geographers on how to make explicit the all-too-often implicit links between their research and global health debates located outside the discipline. PMID:27611662

  17. Contingent workers: Workers' compensation data analysis strategies and limitations.

    Science.gov (United States)

    Foley, Michael; Ruser, John; Shor, Glenn; Shuford, Harry; Sygnatur, Eric

    2014-07-01

    The growth of the contingent workforce presents many challenges in the occupational safety and health arena. State and federal laws impose obligations and rights on employees and employers, but contingent work raises issues regarding responsibilities to maintain a safe workplace and difficulties in collecting and reporting data on injuries and illnesses. Contingent work may involve uncertainty about the length of employment, control over the labor process, degree of regulatory, or statutory protections, and access to benefits under workers' compensation. The paper highlights differences in regulatory protections and benefits among various types of contingent workers and how these different arrangements affect safety incentives. It discusses challenges caused by contingent work for accurate data reporting in existing injury and illness surveillance and benefit programs, differences between categories of contingent work in their coverage in various data sources, and opportunities for overcoming obstacles to effectively using workers' compensation data. © 2014 Wiley Periodicals, Inc.

  18. 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....

  19. Heart Rate and the Role of the Active Receiver during Contingent Electric Shock for Severe Self-Injurious Behavior

    Science.gov (United States)

    Duker, Pieter C.; Van den Munckhof, Marcia

    2007-01-01

    Five individuals, who were treated for severe self-injurious behaviors (SIB) with contingent electric shock, participated. Hereby, each occurrence of the target response was followed by a remotely administered aversive consequence. Participants' heart rates were compared at times when the active device of the equipment for the above procedure was…

  20. Heart rate and the role of the active receiver during contingent electric shock for severe self-injurious behavior

    NARCIS (Netherlands)

    Duker, P.C.C.; Munckhof, M.W.J. van den

    2007-01-01

    Five individuals, who were treated for severe self-injurious behaviors with contingent electric shock, participated. Hereby, each occurrence of the target response was followed by a remotely administered aversive consequence. Participants’ heart rates were compared at times when the active device of

  1. Naloxone induces multiple effects on aversive Pavlovian conditioning in rabbits.

    Science.gov (United States)

    Hernández, L L; Powell, D A

    1983-06-01

    A series of experiments examined the effects of intravenous naloxone treatment on aversive Pavlovian conditioning of eye-blink and heart rate responses, and related unconditioned behaviors, in rabbits. Naloxone treatment before testing attenuated bradycardiac orienting responses to tones used as conditioning stimuli. Naloxone also attenuated conditioned bradycardia when administered either before or after training sessions, but it potentiated conditioned bradycardia during extinction of discriminative conditioning. Naloxone did not influence acquisition or extinction of discriminative eye-blink conditioning or somatic or cardiac responses to shocks used as unconditioned stimuli, but it did decrease locomotor activity. Naloxone treatment immediately after training sessions facilitated acquisition of eye-blink responses. It was concluded that naloxone influences aversive Pavlovian conditioning in more than one way: (a) During training, it appears to alter reception and processing of signals but does not affect subsequent development of somatic responses to the Pavlovian conditioning contingency. (b) After training sessions, naloxone apparently affects consolidation of both somatic and autonomic conditioning. (c) Naloxone also appears to delay extinction of Pavlovian conditioning; this effect may similarly involve changes in a stimulus-processing mechanism or in memory functions, but it apparently does not involve changes in somatomotor responsitivity.

  2. Phenylthiocarbamide produces conditioned taste aversions in mice.

    Science.gov (United States)

    St John, Steven J; Pour, Lindsay; Boughter, John D

    2005-06-01

    Previous work has demonstrated that SWR/J (SW) mice avoid phenylthiocarbamide (PTC) to a greater degree than C3HeB/FeJ mice in 48 h, two-bottle preference tests given in ascending series. The authors hypothesized, based also on previous work, that SW mice might form a conditioned taste aversion over time due to the toxic properties of PTC. We directly tested this hypothesis by attempting to condition a taste aversion to sucrose by injections of PTC. In experiment 1, PTC was nearly as effective as a strong dose of LiCl in reducing sucrose drinking. In experiment 2, the sucrose aversions were parametrically modified by both sucrose concentration and PTC dose, a hallmark of conditioned taste aversion. We conclude that PTC can cause a conditioned taste aversion and discuss the importance of considering toxic effects of aversive tastants when analyzing behavioral strain differences.

  3. Contingency contractor optimization.

    Energy Technology Data Exchange (ETDEWEB)

    Gearhart, Jared Lee; Adair, Kristin Lynn; Jones, Katherine A.; Bandlow, Alisa; Durfee, Justin David.; Jones, Dean A.; Martin, Nathaniel; Detry, Richard Joseph; Nanco, Alan Stewart; Nozick, Linda Karen

    2013-10-01

    The goal of Phase 3 the OSD ATL Contingency Contractor Optimization (CCO) project is to create an engineering prototype of a tool for the contingency contractor element of total force planning during the Support for Strategic Analysis (SSA). An optimization model was developed to determine the optimal mix of military, Department of Defense (DoD) civilians, and contractors that accomplishes a set of user defined mission requirements at the lowest possible cost while honoring resource limitations and manpower use rules. An additional feature allows the model to understand the variability of the Total Force Mix when there is uncertainty in mission requirements.

  4. Contingency contractor optimization.

    Energy Technology Data Exchange (ETDEWEB)

    Gearhart, Jared Lee; Adair, Kristin Lynn; Jones, Katherine A.; Bandlow, Alisa; Detry, Richard Joseph; Durfee, Justin David.; Jones, Dean A.; Martin, Nathaniel; Nanco, Alan Stewart; Nozick, Linda Karen

    2013-06-01

    The goal of Phase 3 the OSD ATL Contingency Contractor Optimization (CCO) project is to create an engineering prototype of a tool for the contingency contractor element of total force planning during the Support for Strategic Analysis (SSA). An optimization model was developed to determine the optimal mix of military, Department of Defense (DoD) civilians, and contractors that accomplishes a set of user defined mission requirements at the lowest possible cost while honoring resource limitations and manpower use rules. An additional feature allows the model to understand the variability of the Total Force Mix when there is uncertainty in mission requirements.

  5. Ambiguity Aversion and the Criminal Process

    OpenAIRE

    Uzi Segal; Alex Stein

    2005-01-01

    This is the first article to examine the effects of ambiguity aversion on the criminal process. Ambiguity aversion is a person’s rational attitude towards probability's indeterminacy. When a person is averse towards such ambiguities, he increases the probability of the unfavorable outcome to reflect that fear. This observation is particularly true about a criminal defendant who faces a jury trial. Neither the defendant nor the prosecution knows whether the jury will convict the defendant. The...

  6. Contingent Faculty as Nonideal Workers

    Science.gov (United States)

    Kezar, Adrianna; Bernstein-Sierra, Samantha

    2016-01-01

    This chapter explores how contingent faculty address the issue of work and family and demonstrates the importance of understanding the diversity of contingent faculty experiences and of underemployment rather than notions of the ideal worker to explain their work lives.

  7. Inequality Aversion and Reciprocity in Moonlighting Games

    Directory of Open Access Journals (Sweden)

    Dirk Engelmann

    2010-10-01

    Full Text Available We study behavior in a moonlighting game with unequal initial endowments. In this game, predictions for second-mover behavior based on inequality aversion are in contrast to reciprocity. We find that inequality aversion explains only few observations. The comparison to a treatment with equal endowments supports the conclusion that behavior is better captured by intuitive notions of reciprocity than by inequality aversion. Extending the model by allowing for alternative reference points promises better performance, but leads to other problems. We conclude that the fact that inequality aversion often works as a good short-hand for reciprocity is driven by biased design choices.

  8. Incremental Contingency Planning

    Science.gov (United States)

    Dearden, Richard; Meuleau, Nicolas; Ramakrishnan, Sailesh; Smith, David E.; Washington, Rich

    2003-01-01

    There has been considerable work in AI on planning under uncertainty. However, this work generally assumes an extremely simple model of action that does not consider continuous time and resources. These assumptions are not reasonable for a Mars rover, which must cope with uncertainty about the duration of tasks, the energy required, the data storage necessary, and its current position and orientation. In this paper, we outline an approach to generating contingency plans when the sources of uncertainty involve continuous quantities such as time and resources. The approach involves first constructing a "seed" plan, and then incrementally adding contingent branches to this plan in order to improve utility. The challenge is to figure out the best places to insert contingency branches. This requires an estimate of how much utility could be gained by building a contingent branch at any given place in the seed plan. Computing this utility exactly is intractable, but we outline an approximation method that back propagates utility distributions through a graph structure similar to that of a plan graph.

  9. 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...... significantly higher levels of ‘kindness’ for low levels of beliefs: at a second-order belief of zero, the probability of choosing the ‘kind’ action is between 43 and 65 percentage points higher than with the other approaches....

  10. Contingency Base Camp Solid Waste Generation

    Science.gov (United States)

    2013-09-01

    wastes gener- ated at Army base camps. The data in this report were obtained from solid waste characterization surveys of base camps in Bosnia, Kosovo ...ER D C/ CE RL T R- 13 -1 7 Contingency Base Camp Solid Waste Generation Co ns tr uc tio n En gi ne er in g R es ea rc h La bo ra to...Contingency Base Camp Solid Waste Generation Stephen D. Cosper, H. Garth Anderson, Kurt Kinnevan, and Byung J. Kim Construction Engineering Research

  11. 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 gener

  12. Risk aversion and religious behaviour

    DEFF Research Database (Denmark)

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

    2017-01-01

    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...

  13. 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.

  14. Aversive behavior induced by optogenetic inactivation of ventral tegmental area dopamine neurons is mediated by dopamine D2 receptors in the nucleus accumbens.

    Science.gov (United States)

    Danjo, Teruko; Yoshimi, Kenji; Funabiki, Kazuo; Yawata, Satoshi; Nakanishi, Shigetada

    2014-04-29

    Dopamine (DA) transmission from the ventral tegmental area (VTA) is critical for controlling both rewarding and aversive behaviors. The transient silencing of DA neurons is one of the responses to aversive stimuli, but its consequences and neural mechanisms regarding aversive responses and learning have largely remained elusive. Here, we report that optogenetic inactivation of VTA DA neurons promptly down-regulated DA levels and induced up-regulation of the neural activity in the nucleus accumbens (NAc) as evaluated by Fos expression. This optogenetic suppression of DA neuron firing immediately evoked aversive responses to the previously preferred dark room and led to aversive learning toward the optogenetically conditioned place. Importantly, this place aversion was abolished by knockdown of dopamine D2 receptors but not by that of D1 receptors in the NAc. Silencing of DA neurons in the VTA was thus indispensable for inducing aversive responses and learning through dopamine D2 receptors in the NAc.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. 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

  17. Comparing the effects of differential reinforcement of other behavior and response-cost contingencies on tics in youth with Tourette syndrome.

    Science.gov (United States)

    Capriotti, Matthew R; Brandt, Bryan C; Ricketts, Emily J; Espil, Flint M; Woods, Douglas W

    2012-01-01

    Tics are rapid, repetitive, stereotyped movements or vocalizations that arise from neurobiological dysfunction and are influenced by environmental factors. Although persons with tic disorders often experience aversive social reactions in response to tics, little is known about the behavioral effects of such consequences. Along several dimensions, the present study compared the effects of two treatments on tics: response cost (RC) and differential reinforcement of other behavior (DRO). Four children with Tourette syndrome were exposed to free-to-tic baseline, DRO, RC, and quasibaseline rebound evaluation conditions using an alternating treatments design. Both DRO and RC produced substantial decreases in tics from baseline levels. No differential effects of DRO and RC contingencies were seen on self-reported stress or in the strength of the reflexive motivating operation (i.e., premonitory urge) believed to trigger tics, and neither condition produced tic-rebound effects. Implications of these findings and directions for future research are discussed.

  18. Eye movements are captured by a perceptually simple conditioned stimulus in the absence of explicit contingency knowledge.

    Science.gov (United States)

    Hopkins, Lauren S; Helmstetter, Fred J; Hannula, Deborah E

    2016-12-01

    Past reports suggest that threatening materials can impact the efficiency of goal-directed behavior. However, questions remain about whether a conditional stimulus (CS) can capture attention as previous results may have been influenced by voluntary prioritization of a to-be-ignored CS. In 2 experiments, eye tracking was used to evaluate whether neutral, perceptually simple materials capture attention when they take on aversive properties via probabilistic fear conditioning with strict methods in place to eliminate voluntary CS prioritization. During training, participants attempted to fixate search targets (i.e., horizontally or vertically oriented rectangles) as quickly as possible to avoid shock. In reality, shock administration was related to rectangle orientation so that 1 rectangle (CS+) predicted shock more often than the other (CS-). Subsequently rectangles became distractors and were to be ignored. At this point, participants were instructed to fixate a new target and incidences of CS capture were examined. Results showed that saccades were made more quickly to the CS+ than the CS- as training progressed, and that oculomotor capture by irrelevant rectangles occurred more often for the CS+ than the CS-. An independent physiological index (skin conductance response) confirmed that contingencies had been learned, as SCR magnitude was greater for CS+ than CS- trials early in the test phase. These effects were documented despite the absence of explicit contingency knowledge, assessed using a postexperimental questionnaire. Collectively, these outcomes indicate that a CS can capture attention despite being task-irrelevant, and that these effects do not depend on conscious awareness of learned contingencies. (PsycINFO Database Record

  19. Cassini launch contingency effort

    Science.gov (United States)

    Chang, Yale; O'Neil, John M.; McGrath, Brian E.; Heyler, Gene A.; Brenza, Pete T.

    2002-01-01

    On 15 October 1997 at 4:43 AM EDT, the Cassini spacecraft was successfully launched on a Titan IVB/Centaur on a mission to explore the Saturnian system. It carried three Radioisotope Thermoelectric Generators (RTGs) and 117 Light Weight Radioisotope Heater Units (LWRHUs). As part of the joint National Aeronautics and Space Administration (NASA)/U.S. Department of Energy (DoE) safety effort, a contingency plan was prepared to address the unlikely events of an accidental suborbital reentry or out-of-orbital reentry. The objective of the plan was to develop procedures to predict, within hours, the Earth impact footprints (EIFs) for the nuclear heat sources released during the atmospheric reentry. The footprint predictions would be used in subsequent notification and recovery efforts. As part of a multi-agency team, The Johns Hopkins University Applied Physics Laboratory (JHU/APL) had the responsibility to predict the EIFs of the heat sources after a reentry, given the heat sources' release conditions from the main spacecraft. (No ablation burn-through of the heat sources' aeroshells was expected, as a result of earlier testing.) JHU/APL's other role was to predict the time of reentry from a potential orbital decay. The tools used were a three degree-of-freedom trajectory code, a database of aerodynamic coefficients for the heat sources, secure links to obtain tracking data, and a high fidelity special perturbation orbit integrator code to predict time of spacecraft reentry from orbital decay. In the weeks and days prior to launch, all the codes and procedures were exercised. Notional EIFs were derived from hypothetical reentry conditions. EIFs predicted by JHU/APL were compared to those by JPL and US SPACECOM, and were found to be in good agreement. The reentry time from orbital decay for a booster rocket for the Russian Progress M-36 freighter, a cargo ship for the Mir space station, was predicted to within 5 minutes more than two hours before reentry. For the

  20. Small Stakes Risk Aversion in the Laboratory

    DEFF Research Database (Denmark)

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

    the “risk aversion temperature” of the subject. We consider evidence from a simple design that tests this assumption. We find that the assumption is strikingly rejected for a large sample of subjects from a population of college students. However, we find that the assumption is not rejected for a large......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...... 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...

  1. Unemployment Benefits, Risk Aversion, and Migration Incentives

    OpenAIRE

    Heitmüller, Axel

    2002-01-01

    With reference to the EU enlargement, a framework is derived which allows the study of the effect of unemployment benefits on the migration decision. While benefits simply increase the expected gain for risk neutral individuals, they work as an insurance device for risk averse migrants; the results for the two groups might differ. Thus, the migration decision is reformulated as monetary lottery and a utility function exhibiting constant relative risk aversion is applied. The model suggests in...

  2. Chinese are more loss averse than British

    OpenAIRE

    Guo, Tieyuan; Spina, Roy

    2016-01-01

    This research investigates how culture might influence loss aversion. Chinese were expected to be more loss averse than British because of cultural differences in regulatory focus. Study 1 reveals that compared with British participants, Chinese participants were less likely to give up gifts they had received in exchange for new gifts. In Study 2, Chinese and British participants imagined buying a computer which either had a high specification and a high price tag (high reference), or a basic...

  3. Alternative Forms of Fit in Contingency Theory.

    Science.gov (United States)

    Drazin, Robert; Van de Ven, Andrew H.

    1985-01-01

    This paper examines the selection, interaction, and systems approaches to fit in structural contingency theory. The concepts of fit evaluated may be applied not only to structural contingency theory but to contingency theories in general. (MD)

  4. Dynamic Contingency Analysis Tool

    Energy Technology Data Exchange (ETDEWEB)

    2016-01-14

    The Dynamic Contingency Analysis Tool (DCAT) is an open-platform and publicly available methodology to help develop applications that aim to improve the capabilities of power system planning engineers to assess the impact and likelihood of extreme contingencies and potential cascading events across their systems and interconnections. Outputs from the DCAT will help find mitigation solutions to reduce the risk of cascading outages in technically sound and effective ways. The current prototype DCAT implementation has been developed as a Python code that accesses the simulation functions of the Siemens PSS�E planning tool (PSS/E). It has the following features: It uses a hybrid dynamic and steady-state approach to simulating the cascading outage sequences that includes fast dynamic and slower steady-state events. It integrates dynamic models with protection scheme models for generation, transmission, and load. It models special protection systems (SPSs)/remedial action schemes (RASs) and automatic and manual corrective actions. Overall, the DCAT attempts to bridge multiple gaps in cascading-outage analysis in a single, unique prototype tool capable of automatically simulating and analyzing cascading sequences in real systems using multiprocessor computers.While the DCAT has been implemented using PSS/E in Phase I of the study, other commercial software packages with similar capabilities can be used within the DCAT framework.

  5. Dynamic Contingency Analysis Tool

    Energy Technology Data Exchange (ETDEWEB)

    2016-01-14

    The Dynamic Contingency Analysis Tool (DCAT) is an open-platform and publicly available methodology to help develop applications that aim to improve the capabilities of power system planning engineers to assess the impact and likelihood of extreme contingencies and potential cascading events across their systems and interconnections. Outputs from the DCAT will help find mitigation solutions to reduce the risk of cascading outages in technically sound and effective ways. The current prototype DCAT implementation has been developed as a Python code that accesses the simulation functions of the Siemens PSS/E planning tool (PSS/E). It has the following features: It uses a hybrid dynamic and steady-state approach to simulating the cascading outage sequences that includes fast dynamic and slower steady-state events. It integrates dynamic models with protection scheme models for generation, transmission, and load. It models special protection systems (SPSs)/remedial action schemes (RASs) and automatic and manual corrective actions. Overall, the DCAT attempts to bridge multiple gaps in cascading-outage analysis in a single, unique prototype tool capable of automatically simulating and analyzing cascading sequences in real systems using multiprocessor computers.While the DCAT has been implemented using PSS/E in Phase I of the study, other commercial software packages with similar capabilities can be used within the DCAT framework.

  6. Contingent kernel density estimation.

    Directory of Open Access Journals (Sweden)

    Scott Fortmann-Roe

    Full Text Available Kernel density estimation is a widely used method for estimating a distribution based on a sample of points drawn from that distribution. Generally, in practice some form of error contaminates the sample of observed points. Such error can be the result of imprecise measurements or observation bias. Often this error is negligible and may be disregarded in analysis. In cases where the error is non-negligible, estimation methods should be adjusted to reduce resulting bias. Several modifications of kernel density estimation have been developed to address specific forms of errors. One form of error that has not yet been addressed is the case where observations are nominally placed at the centers of areas from which the points are assumed to have been drawn, where these areas are of varying sizes. In this scenario, the bias arises because the size of the error can vary among points and some subset of points can be known to have smaller error than another subset or the form of the error may change among points. This paper proposes a "contingent kernel density estimation" technique to address this form of error. This new technique adjusts the standard kernel on a point-by-point basis in an adaptive response to changing structure and magnitude of error. In this paper, equations for our contingent kernel technique are derived, the technique is validated using numerical simulations, and an example using the geographic locations of social networking users is worked to demonstrate the utility of the method.

  7. 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

    2015-01-01

    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. PMID:25698984

  8. Adaptive Contingency Control: Wind Turbine Operation Integrated with Blade Condition Monitoring

    Data.gov (United States)

    National Aeronautics and Space Administration — We report here on first steps towards integrating systems health monitoring with adaptive contingency controls. In the scenario considered, the adaptive controller...

  9. Dietary cravings and aversions during pregnancy.

    Science.gov (United States)

    Hook, E B

    1978-08-01

    Interviews of 250 women concerning dietary changes during pregnancy were undertaken immediately after delivery. With regard to beverages, of women who regularly drank coffee or alcoholic items prior to conception, almost 30% reported a significant drop in ingestion during pregnancy. For coffee this change was attributed primarily to "endogenous" factors e.g., provocation of nausea or a loss of taste for the beverage. Concern regarding maternal or infant health was the most frequent reason for decrease in alcoholic beverages, although endogenous factors were also mentioned. Soda beverages were also ingested less frequently, predominantly because of dieting. The main increase was in milk consumption, primarily attributed to concern for the infant, but many mothers cited only a craving for the beverage. Other foods for which specific cravings were frequently cited were ice cream, sweets, and candy (particularly chocolate), fruits, and fish. Foods for which aversions outnumbered cravings were meats, poultry, and sauces flavored with oregano. Possible explanations for these changes associated with pregnancy are discussed.

  10. Do fish perceive anaesthetics as aversive?

    Directory of Open Access Journals (Sweden)

    Gareth D Readman

    Full Text Available This study addresses a fundamental question in fish welfare: are the anaesthetics used for fish aversive? Despite years of routine general use of many agents, within both scientific research and aquaculture, there is a paucity of information regarding their tolerance and associated behavioural responses by fish. This study examined nine of the most commonly used fish anaesthetic agents, and performed preference tests using adult mixed sex zebrafish (Danio rerio, the most commonly held laboratory fish. Video tracking software quantified swimming behaviour related to aversion for each anaesthetic at 50% of its standard recommended dose compared with clean water in a flow-through chemotaxic choice chamber. Results suggest that several commonly used anaesthetics were aversive, including two of the most commonly recommended and used: MS222 (ethyl 3-aminobenzoate methanesulphate and benzocaine. For ethical best practice, it is recommended that compounds that are aversive, even at low concentration, should no longer be used routinely for anaesthesia or indeed the first step of humane euthanasia of adult zebrafish. Two agents were found not to induce aversive behavioural responses: etomidate and 2,2,2 tribromoethanol. For the millions of adult zebrafish used in laboratories and breeding worldwide, etomidate appears best suited for future routine humane use.

  11. 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

  12. 49 CFR 1542.301 - Contingency plan.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Contingency plan. 1542.301 Section 1542.301... Contingency plan. (a) Each airport operator required to have a security program under § 1542.103(a) and (b) must adopt a contingency plan and must: (1) Implement its contingency plan when directed by TSA....

  13. 49 CFR 1544.301 - Contingency plan.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Contingency plan. 1544.301 Section 1544.301... COMMERCIAL OPERATORS Threat and Threat Response § 1544.301 Contingency plan. Each aircraft operator must adopt a contingency plan and must: (a) Implement its contingency plan when directed by TSA. (b)...

  14. 30 CFR 282.26 - Contingency Plan.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Contingency Plan. 282.26 Section 282.26 Mineral... § 282.26 Contingency Plan. (a) When required by the Director, a lessee shall include a Contingency Plan as part of its request for approval of a Delineation, Testing, or Mining Plan. The Contingency...

  15. Energy Emergency and Contingency Planning

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Region 3 document outlines the purpose of Energy Emergency and Contingency Plans. These plans are intended to help refuges continue to function during energy...

  16. Risk Aversion, Intergenerational Equity and Climate Change

    Energy Technology Data Exchange (ETDEWEB)

    Ha-Duong, Minh [CNRS-CIRED, Paris (France); Treich, N. [LEERNA-INRA, University of Toulouse (France)

    2004-06-01

    The paper investigates a climate-economy model with an iso-elastic welfare function in which one parameter {gamma} measures relative risk-aversion and a distinct parameter {rho} measures resistance to intertemporal substitution. We show both theoretically and numerically that climate policy responds differently to variations in the two parameters. In particular, we show that higher {gamma} but lower {rho} leads to increase emissions control. We also argue that climate-economy models based on intertemporal expected utility maximization, i.e. models where {gamma} ={rho}, may misinterpret the sensitivity of the climate policy to risk-aversion.

  17. 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.

  18. Mobile contingency unit

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Sergio O. da; Magalhaes, Milton P. de [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil); Junqueira, Rodrigo A.; Torres, Carlos A.R. [PETROBRAS Transporte S/A (TRANSPETRO), Rio de Janeiro, RJ (Brazil)

    2009-07-01

    This paper is aimed at presenting what is already a reality in TRANSPETRO in the area covered by OSBRA, a pipeline that carries by-products to the Mid-West region of Brazil. In order to meet the needs of covering occasional accidents, TRANSPETRO counts on a standardized system of emergency management. It is a great challenge to secure an efficient communication along the 964 km of extension, considering that there are shadow zones where it is not possible to use conventional means of communication such as mobile telephony and internet. It was in this context that the Mobile Contingency Unit Via Satellite - MCU was developed, to extend the communication facilities existing in fixed installations to remote places, mainly the pipeline right of ways. In case of emergency, simulation and work in the pipeline right of way, MCU is fully able to provide the same data, voice, closed-circuit TV and satellite video conference facilities that are available in any internal area of the PETROBRAS system. (author)

  19. Sound-contingent visual motion aftereffect

    Directory of Open Access Journals (Sweden)

    Kobayashi Maori

    2011-05-01

    Full Text Available Abstract Background After a prolonged exposure to a paired presentation of different types of signals (e.g., color and motion, one of the signals (color becomes a driver for the other signal (motion. This phenomenon, which is known as contingent motion aftereffect, indicates that the brain can establish new neural representations even in the adult's brain. However, contingent motion aftereffect has been reported only in visual or auditory domain. Here, we demonstrate that a visual motion aftereffect can be contingent on a specific sound. Results Dynamic random dots moving in an alternating right or left direction were presented to the participants. Each direction of motion was accompanied by an auditory tone of a unique and specific frequency. After a 3-minutes exposure, the tones began to exert marked influence on the visual motion perception, and the percentage of dots required to trigger motion perception systematically changed depending on the tones. Furthermore, this effect lasted for at least 2 days. Conclusions These results indicate that a new neural representation can be rapidly established between auditory and visual modalities.

  20. Assessment of SNC 80 and naltrindole within a conditioned taste aversion design.

    Science.gov (United States)

    Hutchinson, A C; Simpson, G R; Randall, J F; Zhang, X; Calderon, S N; Rice, K C; Riley, A L

    2000-08-01

    Although compounds with relative selectivity for the mu and kappa opiate receptors subtypes have been reported to condition taste aversions, it is not known whether systemically administered delta compounds have the ability to produce aversions. To that end, female Long-Evans rats were adapted to water deprivation and were given pairings of a novel saccharin solution and various doses of the selective delta agonist SNC 80 (0.32-10.0 mg/kg; Experiment 1) or the selective delta antagonist naltrindole (1.0-18.0 mg/kg; Experiment 2). For comparison, the relatively selective mu agonist morphine (Experiment 1) and mu antagonist naloxone (Experiment 2) were assessed under identical conditions. Both SNC 80 (Experiment 1) and naltrindole (Experiment 2) were effective as unconditioned stimuli within this design, inducing dose-dependent taste aversions with repeated conditioning trials. Although at no dose did animals injected with SNC 80 differ from those injected with morphine, aversions induced by SNC 80 were acquired at a faster rate than those induced by morphine. Subjects injected with naloxone drank significantly less than those injected with naltrindole at the 10 mg/kg dose, and aversions induced by naloxone at 5.6 and 10 mg/kg were acquired at a faster rate than those induced by naltrindole. Although the basis for opioid agonist- and antagonist-induced taste aversions is not known, the differences between aversions induced by SNC 80 and naltrindole and those induced by morphine and naloxone, respectively, may be a function of their relative selectivity for specific opiate receptor subtypes.

  1. Pharmacological aversion treatment of alcohol dependence. I. Production and prediction of conditioned alcohol aversion.

    Science.gov (United States)

    Howard, M O

    2001-08-01

    Eighty-two hospitalized alcoholics receiving pharmacological aversion therapy (PAT) over a 10-day treatment interval completed cognitive, behavioral, and psychophysiological measures evaluating conditioned aversion to alcohol. Pre-post assessments provided convergent support for the efficacy of PAT vis-à-vis production of conditioned aversion to alcohol. Positive alcohol-related outcome expectancies were significantly reduced, whereas confidence that drinking could be avoided in various high-risk situations for consumption was increased following PAT. Behavioral and cardiac rate assessments revealed significant changes following PAT that were specific to alcoholic beverages and potentially reflective of conditioned alcohol aversion. Patients with more extensive pretreatment experiences with alcohol-associated nausea and greater involvement in antisocial conduct appeared to be less susceptible to the PAT conditioning protocol.

  2. 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

  3. 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…

  4. 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...

  5. 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

  6. 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 substanti

  7. 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 substanti

  8. 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

  9. Appetitive vs. Aversive Conditioning in Humans

    Directory of Open Access Journals (Sweden)

    Marta eAndreatta

    2015-05-01

    Full Text Available In classical conditioning, an initially neutral stimulus (conditioned stimulus, CS becomes associated with a biologically salient event (unconditioned stimulus, US, which might be pain (aversive conditioning or food (appetitive conditioning. After a few associations, the CS is able to initiate either defensive or consummatory responses, respectively. Contrary to aversive conditioning, appetitive conditioning is rarely investigated in humans, although its importance for normal and pathological behaviors (e.g., obesity, addiction is undeniable. The present study intents to translate animal findings on appetitive conditioning to humans using food as an US. Thirty-three participants were investigated between 8 am and 10 am without breakfast in order to assure that they felt hungry. During two acquisition phases, one geometrical shape (avCS+ predicted an aversive US (painful electric shock, another shape (appCS+ predicted an appetitive US (chocolate or salty pretzel according to the participants’ preference, and a third shape (CS- predicted neither US. In an extinction phase, these three shapes plus a novel shape (NEW were presented again without US delivery. Valence and arousal ratings as well as startle and skin conductance (SCR responses were collected as learning indices. We found successful aversive and appetitive conditioning. On the one hand, the avCS+ was rated as more negative and more arousing than the CS- and induced startle potentiation and enhanced SCR. On the other hand, the appCS+ was rated more positive than the CS- and induced startle attenuation and larger SCR. In summary, we successfully confirmed animal findings in (hungry humans by demonstrating appetitive learning and normal aversive learning

  10. Marine oil spill contingency planning

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    According to the practice researching and formulating "The Oil Spill Contingency Plan of South Chinese Sea", this paper analyses and discusses the structure, functions and main contents of marine oil spill contingency planning, programs the organizing and commanding system and emergency response system, and advances the planning and researching method to coordinate comprehensively and to design practically the detailed emergency response steps until to formulate the ease operating programs for the plan implementation (PPI) and the PPI to apply high-techniques supporting emergency administrations and response.

  11. Framing and conflict: aspiration level contingency, the status quo, and current theories of risky choice.

    Science.gov (United States)

    Schneider, S L

    1992-09-01

    The effect of positive versus negative frames on risky choice was examined for a variety of scenarios and risks. Preferences in the positive domain were strong and mainly risk averse, with notable exceptions. Preferences in the negative domain, however, were marked by their inconsistency, shown both by an overwhelming lack of significant majority preferences and a surprisingly strong tendency of individual subjects to vacillate in their negatively framed choices across presentations. This finding is accounted for by a proposed aspiration level contingency in which aspiration levels are systematically set to be more difficult to achieve in the face of a perceived loss than a gain. The implications of the results, and the aspiration level contingency, are explored with respect to current theories of risky choice, including Kahneman and Tversky's (1979) prospect theory and Lopes's (1987, 1990) security-potential/aspiration theory.

  12. A Behavioral Approach to Meeting Contingency Contracting Personnel Requirements

    Science.gov (United States)

    2009-03-01

    Gansler_Commission_Report_Final_071031.pdf, accessed November 2007. Herzberg , Frederick. The Motivation to Work, New York: John Wiley and Sons, 1959. Maslow, Abraham. A Theory of Human...Civilian Contracting Cadre, DCCC, Virtual Contingency Contracting Cadre, VCCC, Gansler Report, recruitment, motivation , incentives, Maslow, Herzberg ...HERZBERG’S MOTIVATION -HYGIENE THEORY .............................21 G. VROOM’S EXPECTANCY THEORY

  13. 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.

  14. Anxious individuals have difficulty learning the causal statistics of aversive environments.

    Science.gov (United States)

    Browning, Michael; Behrens, Timothy E; Jocham, Gerhard; O'Reilly, Jill X; Bishop, Sonia J

    2015-04-01

    Statistical regularities in the causal structure of the environment enable us to predict the probable outcomes of our actions. Environments differ in the extent to which action-outcome contingencies are stable or volatile. Difficulty in being able to use this information to optimally update outcome predictions might contribute to the decision-making difficulties seen in anxiety. We tested this using an aversive learning task manipulating environmental volatility. Human participants low in trait anxiety matched updating of their outcome predictions to the volatility of the current environment, as predicted by a Bayesian model. Individuals with high trait anxiety showed less ability to adjust updating of outcome expectancies between stable and volatile environments. This was linked to reduced sensitivity of the pupil dilatory response to volatility, potentially indicative of altered norepinephrinergic responsivity to changes in this aspect of environmental information.

  15. The premenstrual phase and reactions to aversive events: a study of hormonal influences on emotionality.

    NARCIS (Netherlands)

    Goozen, van St.H.M.; Frijda, N.H.; Wiegant, V.M.; Endert, E.; Poll, van de N.E.

    1996-01-01

    Fifty-eight normal cycle, healthy women were confronted with an aversive, anger-provoking situation in the laboratory. Eighteen women were tested in their follicular phase. A further 40 women were tested in the premenstrual phase, half of whom reported suffering from complaints of premenstrual emoti

  16. Exposure to Sexist Humor and Rape Proclivity: The Moderator Effect of Aversiveness Ratings

    Science.gov (United States)

    Romero-Sanchez, Monica; Duran, Mercedes; Carretero-Dios, Hugo; Megias, Jesus L.; Moya, Miguel

    2010-01-01

    The aim of this study is to explore the effect of exposure to sexist humor about women on men's self-reported rape proclivity. Earlier studies have shown that exposure to this type of humor increases rape proclivity and that funniness responses to jokes are a key element to consider. However, the role of aversiveness responses has not been…

  17. Acute dissociation predicts rapid habituation of skin conductance responses to aversive auditory probes

    NARCIS (Netherlands)

    Giesbrecht, T.; Merckelbach, H.L.G.J.; Burg, L. ter; Cima, M.; Simeon, D.

    2008-01-01

    The present study examined how acute dissociation, trait-like dissociative symptoms, and physiological reactivity relate to each other. Sixty-nine undergraduate students were exposed to 14 aversive auditory probes, while their skin conductance responses were measured. A combination of self-reported

  18. 40 CFR 51.152 - Contingency plans.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false Contingency plans. 51.152 Section 51... FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Prevention of Air Pollution Emergency Episodes § 51.152 Contingency plans. (a) Each contingency plan must— (1) Specify two or more stages of...

  19. The Psychophysics of Contingency Assessment

    Science.gov (United States)

    Allan, Lorraine G.; Hannah, Samuel D.; Crump, Matthew J. C.; Siegel, Shepard

    2008-01-01

    The authors previously described a procedure that permits rapid, multiple within-participant evaluations of contingency assessment (the "streamed-trial" procedure, M. J. C. Crump, S. D. Hannah, L. G. Allan, & L. K. Hord, 2007). In the present experiments, they used the streamed-trial procedure, combined with the method of constant stimuli and a…

  20. Job satisfaction and contingent employment

    NARCIS (Netherlands)

    de Graaf-Zijl, M.

    2012-01-01

    This paper analyses job satisfaction as an aggregate of satisfaction with several job aspects, with special focus on the influence of contingent-employment contracts. Fixed-effect analysis is applied on a longitudinal sample of Dutch employees in four work arrangements: regular, fixed-term, on-call

  1. Job satisfaction and contingent employment

    NARCIS (Netherlands)

    de Graaf-Zijl, M.

    2012-01-01

    This paper analyses job satisfaction as an aggregate of satisfaction with several job aspects, with special focus on the influence of contingent-employment contracts. Fixed-effect analysis is applied on a longitudinal sample of Dutch employees in four work arrangements: regular, fixed-term, on-call

  2. 48 CFR 303.405 - Misrepresentations or violations of the Covenant Against Contingent Fees clause.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Misrepresentations or... INTEREST Contingent Fees 303.405 Misrepresentations or violations of the Covenant Against Contingent Fees clause. (a) HHS personnel shall promptly report suspected misrepresentations or violations of the...

  3. 78 FR 53113 - Approval and Promulgation of Implementation Plans; California; San Joaquin Valley; Contingency...

    Science.gov (United States)

    2013-08-28

    ...). With respect to the level of emission reductions associated with contingency measures, EPA has... contingency measures for 2012 are, therefore, no longer needed. The emission inventory used in the RFP... measuring progress for the annual PM 2.5 standard. The inventory in the 2011 Progress Report, used in the...

  4. 76 FR 76118 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List...

    Science.gov (United States)

    2011-12-06

    ... and Hazardous Substances Pollution Contingency Plan (NCP). The EPA and the State of Texas, through the..., Penalties, Reporting and recordkeeping requirements, Superfund, Water pollution control, Water supply... AGENCY 40 CFR Part 300 National Oil and Hazardous Substances Pollution Contingency Plan; National...

  5. 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)

  6. Selective associations produced solely with appetitive contingencies: the stimulus-reinforcer interaction revisited.

    Science.gov (United States)

    Weiss, S J; Panlilio, L V; Schindler, C W

    1993-03-01

    In studies reporting stimulus-reinforcer interactions in traditional conditioning paradigms, when a tone-light compound was associated with food the light gained stimulus control, but when the compound was paired with shock avoidance the tone gained control. However, the physical nature of the reinforcer-related events (food vs. shock) presented in the presence of the tone-light compound was always confounded with the conditioned hedonic value of the compound's presence relative to its absence. When the compound was paired with shock, its presence was negative relative to its absence (which was shock-free). In contrast, when the compound was paired with food, its presence was positive relative to its absence (which was food-free). The present experiment dealt with this confounding effect by conditioning a tone-light compound to be positive or negative, relative to its absence, solely with food reinforcement. One group of rats received food for responding in the presence of the tone-light compound and no food in its absence. The other group also responded in the presence of the compound, but received food only in its absence. These rats were trained on a chained schedule in which responding in the presence of the tone-light compound produced a terminal link signaled by the absence of the compound; responding ceased in the terminal link because it delayed food delivery. In a test session to assess stimulus control by the elements of the compound, tone and light were presented separately under extinction conditions. Rats that had been exposed to a positive correlation between food and the compound emitted almost double the responses in the presence of the light as in the presence of the tone. In comparison, rats that had been exposed to a negative correlation emitted only two thirds as many responses in the presence of the light as in the presence of the tone. Because this selective association was produced using only food, it appears that the contingencies under

  7. Wind Turbine Contingency Control Through Generator De-Rating

    Science.gov (United States)

    Frost, Susan; Goebel, Kai; Balas, Mark

    2013-01-01

    Maximizing turbine up-time and reducing maintenance costs are key technology drivers for wind turbine operators. Components within wind turbines are subject to considerable stresses due to unpredictable environmental conditions resulting from rapidly changing local dynamics. In that context, systems health management has the aim to assess the state-of-health of components within a wind turbine, to estimate remaining life, and to aid in autonomous decision-making to minimize damage to the turbine. Advanced contingency control is one way to enable autonomous decision-making by providing the mechanism to enable safe and efficient turbine operation. The work reported herein explores the integration of condition monitoring of wind turbines with contingency control to balance the trade-offs between maintaining system health and energy capture. The contingency control involves de-rating the generator operating point to achieve reduced loads on the wind turbine. Results are demonstrated using a high fidelity simulator of a utility-scale wind turbine.

  8. The Expectation-Based Loss-Averse Newsvendor

    OpenAIRE

    Herweg, Fabian

    2012-01-01

    We modify the classic single-period inventory management problem by assuming that the newsvendor is expectation-based loss averse according to Köszegi and Rabin (2006, 2007). Expectation-based loss aversion leads to an endogenous psychological cost of leftovers as well as stockouts. If there are no monetary stockout costs, then the loss-averse newsvendor orders a quantity lower than the quantity ordered by a profit-maximizing newsvendor. If there are positive monetary costs associated with st...

  9. Parental Educational Involvement Conceived as the Arrangement of Contingency Operations

    Science.gov (United States)

    Mellon, Robert C.; Moutavelis, Adrianos G.

    2009-01-01

    This study explored the utility of a conception of parental educational involvement as the arrangement of contingency operations that normatively change: the frequency of children's school-related behaviour, the reinforcing potency of stimuli produced by studying, and children's tendencies to request parental intervention. A child-report measure…

  10. How Precarious Is Contingent Work?

    DEFF Research Database (Denmark)

    Scheuer, Steen

    2015-01-01

    rights and opportunities in the job. The analyses (based on logit modelling, multivariate logistic regression) clearly show that contingent employment (e.g. as a temp) is a risk condition, not only because of the stipulated end of the employment period, but also because it implies a clearly lower chance...... of obtaining a number of the rights and opportunities that are normally connected to an employment relationship....

  11. Indecisiveness aversion and preference for commitment

    OpenAIRE

    Danan, Eric; Guerdjikova, Ani; Zimper, Alexander

    2012-01-01

    International audience; We present an axiomatic model of preferences over menus that is motivated by three assumptions. First, the decision maker is uncertain ex ante (i.e., at the time of choosing a menu) about her ex post (i.e., at the time of choosing an option within her chosen menu) preferences over options, and she anticipates that this subjective uncertainty will not resolve before the ex post stage. Second, she is averse to ex post indecisiveness (i.e., to having to choose between opt...

  12. Contingencies of self-worth.

    Science.gov (United States)

    Crocker, J; Wolfe, C T

    2001-07-01

    Research on self-esteem has focused almost exclusively on level of trait self-esteem to the neglect of other potentially more important aspects such as the contingencies on which self-esteem is based. Over a century ago, W. James (1890) argued that self-esteem rises and falls around its typical level in response to successes and failures in domains on which one has staked self-worth. We present a model of global self-esteem that builds on James' insights and emphasizes contingencies of self-worth. This model can help to (a) point the way to understanding how self-esteem is implicated in affect, cognition, and self-regulation of behavior; (b) suggest how and when self-esteem is implicated in social problems; (c) resolve debates about the nature and functioning of self-esteem; (d) resolve paradoxes in related literatures, such as why people who are stigmatized do not necessarily have low self-esteem and why self-esteem does not decline with age; and (e) suggest how self-esteem is causally related to depression. In addition, this perspective raises questions about how contingencies of self-worth are acquired and how they change, whether they are primarily a resource or a vulnerability, and whether some people have noncontingent self-esteem.

  13. Six-month-old infants' interaction difficulties are mirrored in their preference for perfect contingencies.

    Science.gov (United States)

    Zmyj, Norbert; Klein-Radukic, Sarah

    2015-01-01

    During the first months of life, infants switch from a preference for perfect contingent feedback to a preference for less-than-perfect contingent feedback of their own movements. This is an indicator of increasing social interest since others provide less-than-perfect contingent feedback whereas the self provides perfect contingent feedback. We presented 117 6-month-olds with real-time and delayed video feedback of self-performed leg movements and asked parents about difficulties in various socioemotional domains. It was hypothesized that the more infants prefer real-time and therefore perfect contingent feedback over 7 s delayed and therefore perceived noncontingent feedback, the more difficulties parents will report in interaction and communication with their child. Preference for real-time feedback was related to difficulties in interaction, but not to difficulties in communication. Implications of this finding for infants' socioemotional development and health are discussed.

  14. Counterfactual reasoning for regretted situations involving controllable versus uncontrollable events: the modulating role of contingent self-esteem.

    Science.gov (United States)

    Wilkinson, Meredith R; Ball, Linden J; Alford, David

    2015-01-01

    We report a study that examined the modulating impact of contingent self-esteem on regret intensity for regretted outcomes associated with controllable versus uncontrollable events. The Contingent Self-Esteem Scale (e.g., Kernis & Goldman, 2006) was used to assess the extent to which a person's sense of self-worth is based on self and others' expectations. We found that there was an influence of self-esteem contingency for controllable but not for uncontrollable regret types. For controllable regret types individuals with a high contingent (i.e., unstable) self-esteem reported greater regret intensity than those with a low contingent (i.e., stable) self-esteem. We interpret this finding as reflecting a functional and adaptive role of high contingent self-esteem in terms of mobilizing the application of counterfactual reasoning and planning mechanisms that can enable personal expectations to be achieved in the future.

  15. Counterfactual Reasoning for Regretted Situations Involving Controllable Versus Uncontrollable Events: The Modulating Role of Contingent Self-Esteem

    Science.gov (United States)

    Wilkinson, Meredith R.; Ball, Linden J.; Alford, David

    2015-01-01

    We report a study that examined the modulating impact of contingent self-esteem on regret intensity for regretted outcomes associated with controllable versus uncontrollable events. The Contingent Self-Esteem Scale (e.g., Kernis & Goldman, 2006) was used to assess the extent to which a person’s sense of self-worth is based on self and others’ expectations. We found that there was an influence of self-esteem contingency for controllable but not for uncontrollable regret types. For controllable regret types individuals with a high contingent (i.e., unstable) self-esteem reported greater regret intensity than those with a low contingent (i.e., stable) self-esteem. We interpret this finding as reflecting a functional and adaptive role of high contingent self-esteem in terms of mobilizing the application of counterfactual reasoning and planning mechanisms that can enable personal expectations to be achieved in the future. PMID:25883697

  16. Causes of ambiguity aversion: Known versus unknown preferences

    NARCIS (Netherlands)

    P.P. Wakker (Peter); S.T. Trautmann (Stefan); F.M. Vieider (Ferdinand)

    2008-01-01

    textabstractAmbiguity aversion appears to have subtle psychological causes. Curley, Yates, and Abrams found that the fear of negative evaluation by others (FNE) increases ambiguity aversion. This paper introduces a design in which preferences can be private information of individuals, so that FNE

  17. Appetitive and aversive classical conditioning of female sexual response

    NARCIS (Netherlands)

    S. Both; E. Laan; M. Spiering; T. Nilsson; S. Oomens; W. Everaerd

    2008-01-01

    INTRODUCTION: There is only limited evidence for appetitive classical conditioning of female sexual response, and to date modulation of female sexual response by aversive conditioning has not been studied. AIM: The aim of this article is to study appetitive and aversive classical conditioning of sex

  18. Loss aversion under prospect theory: A parameter-free measurement

    NARCIS (Netherlands)

    M. Abdellaoui (Mohammed); H. Bleichrodt (Han); 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 uti

  19. 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 uti

  20. 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

  1. Modeling non-monotone risk aversion using SAHARA utility functions

    NARCIS (Netherlands)

    A. Chen; A. Pelsser; M. Vellekoop

    2011-01-01

    We develop a new class of utility functions, SAHARA utility, with the distinguishing feature that it allows absolute risk aversion to be non-monotone and implements the assumption that agents may become less risk averse for very low values of wealth. The class contains the well-known exponential and

  2. 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

  3. Loss aversion under prospect theory: A parameter-free measurement

    NARCIS (Netherlands)

    M. Abdellaoui (Mohammed); H. Bleichrodt (Han); 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

  4. 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 a

  5. Does ambiguity aversion survive in experimental asset markets?

    NARCIS (Netherlands)

    Füllbrunn, S.C.; Rau, H.; Weitzel, G.U.

    2014-01-01

    Although a number of theoretical studies explain empirical puzzles in finance with ambi-guity aversion, it is not a given that individual ambiguity attitudes survive in markets. Infact, despite ample evidence of ambiguity aversion in individual decision making, moststudies find no or only limited am

  6. 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…

  7. Radiological Contingency Planning for the Mars Science Laboratory Launch

    Energy Technology Data Exchange (ETDEWEB)

    Paul P. Guss

    2008-04-01

    This paper describes the contingency planning for the launch of the Mars Science Laboratory scheduled for the 21-day window beginning on September 15, 2009. National Security Technologies, LLC (NSTec), based in Las Vegas, Nevada, will support the U.S. Department of Energy (DOE) in its role for managing the overall radiological contingency planning support effort. This paper will focus on new technologies that NSTec’s Remote Sensing Laboratory (RSL) is developing to enhance the overall response capability that would be required for a highly unlikely anomaly. This paper presents recent advances in collecting and collating data transmitted from deployed teams and sensors. RSL is responsible to prepare the contingency planning for a range of areas from monitoring and assessment, sample collection and control, contaminated material release criteria, data management, reporting, recording, and even communications. The tools RSL has available to support these efforts will be reported. The data platform RSL will provide shall also be compatible with integration of assets and field data acquired with other DOE, National Space and Aeronautics and Space Administration (NASA), state, and local resources, personnel, and equipment. This paper also outlines the organizational structure for response elements in radiological contingency planning.

  8. Radiological Contingency Planning for the Mars Science Laboratory Launch

    Energy Technology Data Exchange (ETDEWEB)

    Paul Guss, Robert Augdahl, Bill Nickels, Cassandra Zellers

    2008-04-16

    This paper describes the contingency planning for the launch of the Mars Science Laboratory scheduled for the 21-day window beginning on September 15, 2009. National Security Technologies, LLC (NSTec), based in Las Vegas, Nevada, will support the U.S. Department of Energy (DOE) in its role for managing the overall radiological contingency planning support effort. This paper will focus on new technologies that NSTec’s Remote Sensing Laboratory (RSL) is developing to enhance the overall response capability that would be required for a highly unlikely anomaly. This paper presents recent advances in collecting and collating data transmitted from deployed teams and sensors. RSL is responsible to prepare the contingency planning for a range of areas from monitoring and assessment, sample collection and control, contaminated material release criteria, data management, reporting, recording, and even communications. The tools RSL has available to support these efforts will be reported. The data platform RSL will provide shall also be compatible with integration of assets and field data acquired with other DOE, National Aeronautics and Space Administration, state, and local resources, personnel, and equipment. This paper also outlines the organizational structure for response elements in radiological contingency planning.

  9. 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.

  10. 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.

  11. Does contingent reinforcement strengthen operant behavior?

    OpenAIRE

    Nevin, John A.; Smith, Laurence D.; Roberts, Jean

    1987-01-01

    In Experiment 1, pigeons were trained to peck keys with equal food-reinforcement schedules in components that ended with either noncontingent or contingent transitions to a third component with a five-fold richer schedule. Response rates were higher in the initial component with contingent transitions, but resistance to prefeeding or extinction was not consistently greater. Experiment 2 also included noncontingent or contingent transitions to a signaled period of nonreinforcement. There was n...

  12. Automated Contingency Management for Propulsion Systems

    Data.gov (United States)

    National Aeronautics and Space Administration — Increasing demand for improved reliability and survivability of mission-critical systems is driving the development of health monitoring and Automated Contingency...

  13. Performance by gender in a stop-smoking program combining hypnosis and aversion.

    Science.gov (United States)

    Johnson, D L; Karkut, R T

    1994-10-01

    Increased rates of smoking initiation and smoking-related illness among women have narrowed the gender gap in smoking behavior. Past studies of performance by gender in prevention and treatment programs have reported reduced success with women and have suggested a need for stronger interventions having greater effects on both genders' smoking cessation. A field study of 93 male and 93 female CMHC outpatients examined the facilitation of smoking cessation by combining hypnosis and aversion treatments. After the 2-wk. program, 92% or 86 of the men and 90% or 84 of the women reported abstinence, and at 3-mo. follow-up, 86% or 80 of the men and 87% or 81 of the women reported continued abstinence. Although this field study in a clinical setting lacked rigorous measurement and experimental controls, the program suggested greater efficacy of smoking cessation by both sexes for combined hypnosis and aversion techniques.

  14. 75 FR 44932 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List...

    Science.gov (United States)

    2010-07-30

    ... AGENCY 40 CFR Part 300 National Oil and Hazardous Substances Pollution Contingency Plan; National... substances, Intergovernmental relations, Natural resources, Oil pollution, Penalties, Reporting and..., Compensation, and Liability Act (CERCLA) of 1980, is an Appendix of the National Oil and Hazardous...

  15. 78 FR 70231 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List...

    Science.gov (United States)

    2013-11-25

    ... wastes may have included solvents, acids, bases, paints, and heavy metals. The wastes were deposited in..., Intergovernmental relations, Penalties, Reporting and recordkeeping requirements, Superfund, Water pollution control... AGENCY 40 CFR Part 300 National Oil and Hazardous Substances Pollution Contingency Plan;...

  16. Three essays on contingent valuation

    Science.gov (United States)

    Beatty, Timothy Kenneth Munro

    2001-07-01

    This dissertation consists of three essays on the contingent valuation methodology. The first essay develops a theoretical model of how agents respond to willingness to pay questions in a survey context. In particular, this essay focuses on the difference between a voluntary contribution mechanism and a mandatory contribution mechanism. The second essay applies this theory to a survey of willingness to pay for renewable energy by varying the mechanism by which the public good is supplied. The third essay proposes a methodology for choosing the number, location and range of contributions or bid levels in dichotomous choice contingent valuation surveys. The first essay, "Mandatory vs. Voluntary Payment to a Public Good" models the differing incentive effects of two different payment mechanisms in contingent valuations surveys. It is shown that under rationed voluntary payment (where each agent can contribute either a fixed amount or nothing) there exists a Nash equilibrium in which the level of public good provided is strictly below the level provided under a mandatory provision rule. This result is generalized to hypothetical valuation surveys and a set of condition ranking willingness to pay under each mechanism is described. The second essay "Valuing a Public Good" describes the result of a survey designed to test the above theory. This essay considers willingness to pay for renewable energy. In order to test the theory, a split sample survey of over fifteen hundred respondents was conducted. One half of the sample was asked whether they would volunteer to pay for green power and the other half was asked whether they would vote to support a program in which the entire population was required to contribute towards the provision of the public good. On average, respondents' willingness to pay was higher for the public good provided by the mandatory provision mechanism. The third essay describes the literature on how the contribution or bid levels can be chosen to

  17. Contingent negative variation of mood disorder patients

    Institute of Scientific and Technical Information of China (English)

    Yingzhi Lu; Wenbin Zong; Qingtao Ren; Jinyu Pu; Jun Chen; Juan Li; Xingshi Chen; Yong Wang

    2011-01-01

    Studies on brain-evoked potential and contingent negative variation (CNV) in mood disorder remain controversial. To date, no CNV difference between unipolar and bipolar depression has been reported. Brain-evoked potentials were measured in the present study to analyze CNV in three subtypes of mood disorder (mania, unipolar depression, and bipolar depression), and these results were compared with normal controls. In the mania group, CNV amplitude B was greater than in controls, and the depression group exhibited lower CNV amplitude B and smaller A-S'2 area, and prolonged post-imperative negative variation latency. The CNV comparison between unipolar and bipolar depression found that the prolonged post-imperative negative variation latency was only in unipolar depression. These results suggest that prolonged post-imperative negative variation latency is a characteristic of unipolar depression, and CNV amplitude change is a state characteristic of mood disorder patients.

  18. Neuronal mechanisms for pain-induced aversion behavioral studies using a conditioned place aversion test.

    Science.gov (United States)

    Minami, Masabumi

    2009-01-01

    Pain consists of sensory discriminative and negative affective components. Although the neural systems responsible for the sensory component of pain have been studied extensively, the neural basis of the affective component is not well understood. Recently, behavioral studies using conditioned place aversion (CPA) tests have successfully elucidated the neural circuits and mechanisms underlying the negative affective component of pain. Excitotoxic lesions of the anterior cingulate cortex (ACC), central amygdaloid nucleus, basolateral amygdaloid nucleus (BLA), or bed nucleus of the stria terminalis (BNST) suppressed intraplantar formalin-induced aversive responses. Glutamatergic transmission within the ACC and BLA via NMDA receptors was shown to play a critical role in the affective component of pain. In the BNST, especially its ventral part, noradrenergic transmission via beta-adrenergic receptors was demonstrated as important for pain-induced aversion. Because persistent pain is frequently associated with psychological and emotional dysfunction, studies of the neural circuits and the molecular mechanisms involved in the affective component of pain may have considerable clinical importance in the treatment of chronic pain.

  19. Contingent Diversity on Anthropic Landscapes

    Directory of Open Access Journals (Sweden)

    William Balée

    2010-02-01

    Full Text Available Behaviorally modern human beings have lived in Amazonia for thousands of years. Significant dynamics in species turnovers due to human-mediated disturbance were associated with the ultimate emergence and expansion of agrarian technologies in prehistory. Such disturbances initiated primary and secondary landscape transformations in various locales of the Amazon region. Diversity in these locales can be understood by accepting the initial premise of contingency, expressed as unprecedented human agency and human history. These effects can be accessed through the archaeological record and in the study of living languages. In addition, landscape transformation can be demonstrated in the study of traditional knowledge (TK. One way of elucidating TK distinctions between anthropic and nonanthropic landscapes concerns elicitation of differential labeling of these landscapes and more significantly, elicitation of the specific contents, such as trees, occurring in these landscapes. Freelisting is a method which can be used to distinguish the differential species compositions of landscapes resulting from human-mediated disturbance vs. those which do not evince records of human agency and history. The TK of the Ka’apor Indians of Amazonian Brazil as revealed in freelisting exercises shows differentiation of anthropogenic from high forests as well as a recognition of diversity in the anthropogenic forests. This suggests that the agents of human-mediated disturbance and landscape transformation in traditional Amazonia encode diversity and contingency into their TK, which encoding reflects past cultural influence on landscape and society over time.

  20. 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.

  1. Contingency Planning. Technical Assistance Bulletin 35.

    Science.gov (United States)

    O'Toole, C. P.

    This bulletin describes a set of general guidelines for developing contingency plans that prepare school systems to cope with expected and unexpected disruptions in the educational process. Typically, contingency plans are prepared to anticipate consequences of school desegregation, natural disasters, bomb threats, or mass demonstrations. The…

  2. The Role of Contingency in Classical Conditioning.

    Science.gov (United States)

    Papini, Mauricio R.; Bitterman, M. E.

    1990-01-01

    Early experiments suggesting that classical conditioning depends on the contingency between conditioned stimulus (CS) and the unconditioned stimulus (US) are reconsidered along with later evidence that shows conditioning of the CS and its context in random training. CS-US contingency is neither necessary nor sufficient for conditioning. (SLD)

  3. Contingency management: perspectives of Australian service providers.

    Science.gov (United States)

    Cameron, Jacqui; Ritter, Alison

    2007-03-01

    Given the very positive and extensive research evidence demonstrating efficacy and effectiveness of contingency management, it is important that Australia explore whether contingency management has a role to play in our own treatment context. Qualitative interviews were conducted with 30 experienced alcohol and drug practitioners, service managers and policy-makers in Victoria. Interviewees were selected to represent the range of drug treatment services types and included rural representation. A semi-structured interview schedule, covering their perceptions and practices of contingency management was used. All interviews were transcribed verbatim and analysed using N2 qualitative data analysis program. The majority of key informants were positively inclined toward contingency management, notwithstanding some concerns about the philosophical underpinnings. Concerns were raised in relation to the use of monetary rewards. Examples of the use of contingency management provided by key informants demonstrated an over-inclusive definition: all the examples did not adhere to the key principles of contingency management. This may create problems if a structured contingency management were to be introduced in Australia. Contingency management is an important adjunctive treatment intervention and its use in Australia has the potential to enhance treatment outcomes. No unmanageable barriers were identified in this study.

  4. Overseas Contingency Operations Funding: Background and Status

    Science.gov (United States)

    2017-02-07

    Operations Funding: Background and Status Congressional Research Service Summary The Department of Defense (DOD) estimates that through FY2016...Contingency Operations Funding: Background and Status Congressional Research Service Contents Introduction...Contingency Operations Funding: Background and Status Congressional Research Service 2 budget to which government financiers increasingly turn to

  5. Conditioned aversion of aluminum sulfate in black ducks

    Science.gov (United States)

    Sparling, D.W.

    1990-01-01

    Three experiments were conducted to determine if reduced consumption of foods with elevated Al levels by black ducks (Anas rubripes) was due to taste aversion, conditioned taste aversion or malaise. Black ducks preferred a diet with 1,000 ppm Al over a control diet but ate less of a diet with 5,000 ppm Al. Prior experience with the high Al diet enhanced preference for the control diet. Changes in body weight and food consumption through time suggested that aversion to the high Al diet was a conditioned response to mild malaise.

  6. The Contingent Character of Necessity

    Directory of Open Access Journals (Sweden)

    Luis Guzmán

    2006-12-01

    Full Text Available One of the most frequent criticisms raised against Hegel has to do with the totalizing aspect of his system, which determines what is as absolutely necessary. The Science of Logic, being the conceptual edifice upon which his whole system is built, is the appropriate place to determine the specific meaning of the Hegelian concepts. The following paper offers a detailed analysis on the chapter on Actuality (Wirklichkeit in the Science of Logic, in order to show how the concept of absolute necessity not only includes within it, but also contains as a structural element, the concept of contingency. In this manner a deflationary interpretation is generated in which the absolutely necessary character of actuality should not be understood as grounded on a pre-established end that inexorably determines actuality, but rather as an interpretive movement, in recollection, of its process.

  7. Contingent Conspiracies: Art, Philosophy, Science

    DEFF Research Database (Denmark)

    Wilson, Alexander

    2013-01-01

    , it is difficult not to detect in this principle a hint of the kantian sublime. This paper will offer a survey of these and other findings drawn from my doctoral research. Following a speculative pragmatic approach, several implicit conceptual links between art practice (understood as an aesthetic concern......The question of whether creativity comes from being “open” or “closed” to contingent processes, deeply intersects art-historical discourse on authorship, style, technique and practice: from the Greek notion of the Daimon, through commedia dell'arte’s improvised styles and romanticism’s investment...... distributions (chaos). Perhaps most intriguingly of all, on the “edge of chaos”, between order and randomness, universal computing (Turing) has been shown to emerge in simple rule-based systems such as Conway’s “Game of Life” and Wolfram’s “rule 110”, implying that any computational universe can be emulated...

  8. The use of an unpleasant sound unconditional stimulus in an aversive conditioning procedure with 8- to 11-year-old children.

    Science.gov (United States)

    Neumann, David L; Waters, Allison M; Westbury, H Rae; Henry, Julie

    2008-12-01

    The study of aversive Pavlovian conditioning in children can contribute to our understanding of how fears are acquired and extinguished during development. However, methodological issues hamper further research because of ethical and procedural concerns regarding the use of traditional aversive unconditional stimuli (USs) and no established method to measure trial-by-trial changes in the child's expectancy of the US. The present experiment used geometric shape conditional stimuli (CSs) and an unpleasant sound US with 8- to 11-year-old children. Reliable acquisition and extinction were observed with first, second, and third interval skin conductance responses, on-line expectancy judgments, and post-conditioning subjective ratings of pleasantness and arousal. The experiment confirms the novel use of an unpleasant sound of metal scraping on slate as a US in aversive conditioning with children. The methods have the potential to facilitate the ethical conduct of aversive conditioning research in children using psychophysiological, affective, and self-report expectancy measures.

  9. 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

  10. 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.

  11. A feedback neural circuit for calibrating aversive memory strength.

    Science.gov (United States)

    Ozawa, Takaaki; Ycu, Edgar A; Kumar, Ashwani; Yeh, Li-Feng; Ahmed, Touqeer; Koivumaa, Jenny; Johansen, Joshua P

    2017-01-01

    Aversive experiences powerfully regulate memory formation, and memory strength is proportional to the intensity of these experiences. Inhibition of the neural circuits that convey aversive signals when they are predicted by other sensory stimuli is hypothesized to set associative memory strength. However, the neural circuit mechanisms that produce this predictive inhibition to regulate memory formation are unknown. Here we show that predictive sensory cues recruit a descending feedback circuit from the central amygdala that activates a specific population of midbrain periaqueductal gray pain-modulatory neurons to control aversive memory strength. Optogenetic inhibition of this pathway disinhibited predicted aversive responses in lateral amygdala neurons, which store fear memories, resulting in the resetting of fear learning levels. These results reveal a control mechanism for calibrating learning signals to adaptively regulate the strength of behavioral learning. Dysregulation of this circuit could contribute to psychiatric disorders associated with heightened fear responsiveness.

  12. Ambiguity aversion in a delay analogue of the Ellsberg Paradox

    Directory of Open Access Journals (Sweden)

    Bethany J. Weber

    2012-07-01

    Full Text Available Decision makers are often ambiguity averse, preferring options with subjectively known probabilities to options with unknown probabilities. The Ellsberg paradox is the best-known example of this phenomenon. Ambiguity has generally been studied in the domain of risky choice, and many theories of ambiguity aversion deal with ambiguity only in this context. However, ambiguity aversion may occur in other contexts. In the present experiment, we examine the effects of ambiguity in intertemporal choice. Subjects imagine they are expecting a package and must choose between two delivery options. Some delivery times are exact. Others are ambiguous, with delivery possible over a range of dates. This problem was structurally identical to the Ellsberg paradox. Subjects showed the same pattern of responses as in the traditional Ellsberg paradox, with each delivery service preferred when it was the unambiguous option. Ambiguity aversion is not specific to risk, but can also occur in other domains.

  13. 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.

  14. The Comparative Analysis of Aversive and Ordinary Noise.

    Science.gov (United States)

    Mobley, C. Marion, Jr.

    There is a vast amount of literature concerning the psychological and physiological effects of ordinary noise on the individual. However, few publications have addressed the analysis of aversive noise. This research analyzes three noises which produce the familiar goose flesh or chilling effect responsivity. These aversive sounds which are made by chalk squeaking on the chalkboard, fingernails on the chalkboard and rubbing styrofoam against a smooth surface are digitally compared to ordinary noise to show how these aversive sounds differ from sounds which are only annoying. This work, which uses Fast Fourier Transform (FFT) analysis is a combination with cross correlation analysis and other innovative methods to produce comparative data on noises, illustrates subtle differences between ordinary and aversive noise which may be useful for future work in acoustics or experimental psychology. The literature review shows disagreement among the numerous works on the effects of ordinary noise on human subjects. One explanation for this difference is the failure to adequately measure and define the dynamic nature of the noise used. The existing literature also establishes that a mixture of tones plus random noise is more annoying (but not aversive) than either the random noise or the tones alone. This investigation shows that one property of aversive noises is the combination of randomness plus tones which vary rapidly with time. This paper utilizes a new digital technique which improves the FFT analyzer resolution by a factor of 25. The resulting +/-2 Hz accuracy facilitated the presentation of frequency variation as a function of time data. Other computer generated graphical data includes the percent harmonic deviation as a function of time, the rate of change of fundamental frequency, and the rate of change in harmonic deviation. From these dynamic data, average values are calculated which show the aversive noise to be consistently greater in mean frequency deviation

  15. Risk-Averse Control of Undiscounted Transient Markov Models

    CERN Document Server

    Cavus, Ozlem

    2012-01-01

    We use Markov risk measures to formulate a risk-averse version of the undiscounted total cost problem for a transient controlled Markov process. We derive risk-averse dynamic programming equations and we show that a randomized policy may be strictly better than deterministic policies, when risk measures are employed. We illustrate the results on an optimal stopping problem and an organ transplant problem.

  16. Loss aversion with a state-dependent reference point

    OpenAIRE

    Georgi, Enrico; Post, Thierry

    2010-01-01

    This study investigates loss aversion when the reference point is a state-dependent random variable. This case describes, for example, a money manager being evaluated relative to a risky benchmark index rather than a fixed target return level. Using a state-dependent structure, prospects are more (less) attractive if they depend positively (negatively) on the reference point. In addition, the structure avoids an inherent aversion to risky prospects and yields no losses when the prospect and t...

  17. Risk Aversion, Risk Behavior, and Demand for Insurance: A Survey

    OpenAIRE

    J. Francois Outreville

    2014-01-01

    Determinants of risk attitudes of individuals are of great interest in the growing area of behavioral economics that focuses on the individual attributes, psychological or otherwise, that shape common financial and investment practices. The purpose of this paper is to review the empirical literature on risk aversion (and risk behavior) with a particular focus on insurance demand or consumption. Empirical research on risk aversion may be categorized into two main areas: (1) the measurement and...

  18. 'Too many girls, too much dowry': son preference and daughter aversion in rural Tamil Nadu, India.

    Science.gov (United States)

    Diamond-Smith, Nadia; Luke, Nancy; McGarvey, Stephen

    2008-10-01

    The southern Indian state of Tamil Nadu has experienced a dramatic decline in fertility, accompanied by a trend of increased son preference. This paper reports on findings from qualitative interviews with women in rural villages about their fertility decision-making. Specifically addressed are the reasons behind increasing son preference and the consequences of this change. Findings suggest that daughter aversion, fuelled primarily by the perceived economic burden of daughters due to the proliferation of dowry, is playing a larger role in fertility decision-making than son preference. The desire for a son is often trumped by the worry over having many daughters. Women use various means of controlling the sex of their children, which in this study appear to be primarily female infanticide. It is important to distinguish between son preference and daughter aversion and to examine repercussions of low fertility within this setting.

  19. The impact of perceived self-efficacy on memory for aversive experiences.

    Science.gov (United States)

    Brown, Adam D; Joscelyne, Amy; Dorfman, Michelle L; Marmar, Charles R; Bryant, Richard A

    2012-01-01

    Self-efficacy is a key construct underlying healthy functioning and emotional well-being. Perceptions of uncontrollability, unpredictability, and low self-efficacy are consistently associated with negative mental health outcomes, such as post-traumatic stress disorder (PTSD). To test the causal relation between perceived coping self-efficacy and stress responses we employed a trauma film paradigm in which college students (N=33) viewed a graphic film of the aftermath of a motor vehicle accident following a high (HSE) or low self-efficacy (LSE) induction. Participants were tested for intrusions, distress, and memory recall for the film over the following 24 hours. LSE participants recalled more central details than HSE participants. Further, HSE participants reported fewer negative intrusions immediately following the film and at 24 hours. These findings suggest that strategies that increase perceived coping self-efficacy may reduce intrusive recollections of an aversive event, and also reduce the attentional bias associated with remembering aversive stimuli.

  20. Contingency contrast effects in discrimination conditioning.

    Science.gov (United States)

    Grings, W W; Givens, M C; Carey, C A

    1979-09-01

    Three experiments observed differential electrodermal responding to signal stimuli (CSs) by contrasting positive, random, and negative contingencies between the signals and strong stimuli (UCSs). Experimentation began as a test of the proposition that electrodermal response to a random signal (or CSR) would lie between the response to a reinforced or excitatory stimulus (CS+) and that to a nonreinforced or inhibitory stimulus (CS- or CSI). A clear intermediate position for CSR did not result. Instead it appeared that CSR was operating as a mildly excitatory signal. This led to a second experiment where response to pairs of stimuli with different contingent relations could be compared in independent samples. The pairs were CS+ and CS-, CS+ and CSR, and CSR and CS-. Differential responding was observed in all pairs and response to CSR was significantly larger in the group receiving CSR with CS- than it was in the group receiving CSR with CS+. A contingency contrast effect was suggested. A third experiment explored the implications of a contingency contrast effect by varying overall UCS density, the duration of "safety intervals," and the presence or absence of instructions about contingencies. The UCS density and instruction variables influenced the differential performance to CSR and CS-, a result that was interpreted as further evidence for a perceptual contingency-contrast effect. Some theoretical implications of such a contrast phenomenon are examined, as they apply to autonomic learning. The CS is interpreted as a signal supplying contingency information that is dependent upon a complex of factors in the stimulation environment.

  1. Instructed knowledge shapes feedback-driven aversive learning in striatum and orbitofrontal cortex, but not the amygdala.

    Science.gov (United States)

    Atlas, Lauren Y; Doll, Bradley B; Li, Jian; Daw, Nathaniel D; Phelps, Elizabeth A

    2016-05-12

    Socially-conveyed rules and instructions strongly shape expectations and emotions. Yet most neuroscientific studies of learning consider reinforcement history alone, irrespective of knowledge acquired through other means. We examined fear conditioning and reversal in humans to test whether instructed knowledge modulates the neural mechanisms of feedback-driven learning. One group was informed about contingencies and reversals. A second group learned only from reinforcement. We combined quantitative models with functional magnetic resonance imaging and found that instructions induced dissociations in the neural systems of aversive learning. Responses in striatum and orbitofrontal cortex updated with instructions and correlated with prefrontal responses to instructions. Amygdala responses were influenced by reinforcement similarly in both groups and did not update with instructions. Results extend work on instructed reward learning and reveal novel dissociations that have not been observed with punishments or rewards. Findings support theories of specialized threat-detection and may have implications for fear maintenance in anxiety.

  2. 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.

  3. Contingency awareness shapes acquisition and extinction of emotional responses in a conditioning model of pain-related fear

    Directory of Open Access Journals (Sweden)

    Franziska eLabrenz

    2015-11-01

    CS-. Contingency accuracy predicted variance in the formation of positive responses to safety cues while no predictive value was found for danger cues following acquisition and for neither cue following extinction.Our findings underscore specific roles of learned danger and safety in pain-related acquisition and extinction. Contingency accuracy appears to distinctly impact learned emotional responses to safety and danger cues, supporting aversive learning to occur independently from CS-US awareness. The interplay of cognitive and emotional factors in shaping excitatory and inhibitory pain-related learning may contribute to altered pain processing, underscoring its clinical relevance in chronic pain.

  4. Lossed in Translation: An Off-the-Shelf Method to Recover Probabilistic Beliefs from Loss-Averse Agents

    NARCIS (Netherlands)

    Offerman, T.; Palley, A.

    2013-01-01

    Although strictly proper rules are designed to truthfully elicit subjective probabilistic beliefs, experimental results have shown that risk aversion causes agents to bias their reports towards the rule's baseline probability of 1/2, and a conservative preference for certain outcomes leads agents wi

  5. Effects of Aversive Stimuli beyond Defensive Neural Circuits: Reduced Excitability in an Identified Neuron Critical for Feeding in "Aplysia"

    Science.gov (United States)

    Shields-Johnson, Maria E.; Hernandez, John S.; Torno, Cody; Adams, Katherine M.; Wainwright, Marcy L.; Mozzachiodi, Riccardo

    2013-01-01

    In "Aplysia," repeated trials of aversive stimuli produce long-term sensitization (LTS) of defensive reflexes and suppression of feeding. Whereas the cellular underpinnings of LTS have been characterized, the mechanisms of feeding suppression remained unknown. Here, we report that LTS training induced a long-term decrease in the excitability of…

  6. Motivation versus aversive processing during perception.

    Science.gov (United States)

    Padmala, Srikanth; Pessoa, Luiz

    2014-06-01

    Reward facilitates performance and boosts cognitive performance across many tasks. At the same time, negative affective stimuli interfere with performance when they are not relevant to the task at hand. Yet, the investigation of how reward and negative stimuli impact perception and cognition has taken place in a manner that is largely independent of each other. How reward and negative emotion simultaneously contribute to behavioral performance is currently poorly understood. The aim of the present study was to investigate how the simultaneous manipulation of positive motivational processing (here manipulated via reward) and aversive processing (here manipulated via negative picture viewing) influence behavior during a perceptual task. We tested 2 competing hypotheses about the impact of reward on negative picture viewing. On the one hand, suggestions about the automaticity of emotional processing predict that negative picture interference would be relatively immune to reward. On the other, if affective visual processing is not obligatory, as we have argued in the past, reward may counteract the deleterious effect of more potent negative pictures. We found that reward counteracted the effect of potent, negative distracters during a visual discrimination task. Thus, when sufficiently motivated, participants were able to reduce the deleterious impact of bodily mutilation stimuli.

  7. STUDI KOMITMEN ORGANISASIONAL: PEKERJA CONTINGENT DAN SURVIVOR

    Directory of Open Access Journals (Sweden)

    Fenika Walani

    2015-08-01

    Full Text Available In recent years, contingent and survivor workers have emerged as a common reality in business activities. Unfortunately, contingent worker has high job insecurity on his employment status. On the other side, downsizing activities can result in decreasing job security of survivor worker. As a consequence, both contingent and survivor workers very potential have low organizational commitment. However, organizations still have an opportunity to give their workers an exclusive treatment for building organizational commitment without ignoring the fact that workers have other commitment foci.

  8. The coexistence of overestimation and underweighting of rare events and the contingent recency effect

    Directory of Open Access Journals (Sweden)

    Greg Barron

    2009-10-01

    Full Text Available Previous research demonstrates overestimation of rare events in judgment tasks, and underweighting of rare events in decisions from experience. The current paper presents three laboratory experiments and a field study that explore this pattern. The results suggest that the overestimation and underweighting pattern can emerge in parallel. Part of the difference between the two tendencies can be explained as a product of a contingent recency effect: Although the estimations reflect negative recency, choice behavior reflects positive recency. A similar pattern is observed in the field study: Immediately following an aversive rare-event (i.e., a suicide bombing people believe the risk decreases (negative recency but at the same time exhibit more cautious behavior (positive recency. The rest of the difference is consistent with two well established mechanisms: judgment error and the use of small samples in choice. Implications for the two-stage choice model are discussed.

  9. A systematic evidence review of school-based group contingency interventions for students with challenging behavior.

    Science.gov (United States)

    Maggin, Daniel M; Johnson, Austin H; Chafouleas, Sandra M; Ruberto, Laura M; Berggren, Melissa

    2012-10-01

    The purpose of this review was to synthesize the research underlying group contingency interventions to determine whether there is sufficient evidence to support their use for managing the classroom behavior of students with behavioral difficulties. An application of the What Works Clearinghouse (WWC) procedures for evaluating single-subject research revealed that the research investigating group contingencies demonstrated sufficient rigor, evidence, and replication to label the intervention as evidence-based. These findings were further supported across five quantitative indices of treatment effect. The results associated with the application of the WWC procedures and quantitative evaluations were supplemented with additional systematic coding of methodological features and study characteristics to evaluate the populations and conditions under which the effects of the group contingency best generalize. Findings associated with this coding revealed that the lack of detailed reporting across studies limited our ability to determine for whom and under what conditions group contingencies are best suited.

  10. Visual learning in the perception of texture: simple and contingent aftereffects of texture density.

    Science.gov (United States)

    Durgin, F H; Proffitt, D R

    1996-01-01

    Novel results elucidating the magnitude, binocularity and retinotopicity of aftereffects of visual texture density adaptation are reported as is a new contingent aftereffect of texture density which suggests that the perception of visual texture density is quite malleable. Texture aftereffects contingent upon orientation, color and temporal sequence are discussed. A fourth effect is demonstrated in which auditory contingencies are shown to produce a different kind of visual distortion. The merits and limitations of error-correction and classical conditioning theories of contingent adaptation are reviewed. It is argued that a third kind of theory which emphasizes coding efficiency and informational considerations merits close attention. It is proposed that malleability in the registration of texture information can be understood as part of the functional adaptability of perception.

  11. Effects of contingent self-esteem on depressive symptoms and suicidal behavior.

    Science.gov (United States)

    Lakey, Chad E; Hirsch, Jameson K; Nelson, Lyndsay A; Nsamenang, Sheri A

    2014-01-01

    Contingent self-esteem, or self-worth hinged upon successfully meeting standards or attaining goals, requires continual maintenance and validation. Despite the inherent instability that accompanies contingent self-esteem, relatively little is known about how it relates to markers of mental health. A sample of 371 college students completed measures of self-esteem, contingent self-esteem, suicidal behaviors, and depression. Individuals with fragile low self-esteem, described as highly contingent, reported greater depressive symptoms and suicidal behavior. Among those with secure high self-esteem, or high yet noncontingent, depression and suicide risk were markedly lower. Therapeutically promoting positive but noncontingent self-worth may reduce poor mental health outcomes.

  12. Integrating Structural Health Management with Contingency Control for Wind Turbines

    Directory of Open Access Journals (Sweden)

    Kai Goebel

    2013-01-01

    Full Text Available Maximizing turbine up-time and reducing maintenance costs are key technology drivers for wind turbine operators. Components within wind turbines are subject to considerable stresses due to unpredictable environmental conditions resulting from rapidly changing local dynamics. In that context, systems health management has the aim to assess the state-of-health of components within a wind turbine, to estimate remaining life, and to aid in autonomous decision-making to minimize damage to the turbine. Advanced contingency control is one way to enable autonomous decision-making by providing the mechanism to enable safe and efficient turbine operation. The work reported herein explores the integration of condition monitoring of wind turbine blades with contingency control to balance the trade-offs between maintaining system health and energy capture. Results are demonstrated using a high fidelity simulator of a utility-scale wind turbine.

  13. [Ottawa National Wildlife Refuge : Disease Contingency Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Disease Contingency Plan for Ottawa NWR provides background information on disease surveillance; an inventory of Refuge personnel, equipment, and resources; and...

  14. Energy Emergency Contingency Plan: Clarence Cannon NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Energy Emergency Contingency Plan for Clarence Cannon NWR outlines energy requirements for the Refuge and tables of projected energy reduction, energy...

  15. Gaze-Contingent Music Reward Therapy for Social Anxiety Disorder: A Randomized Controlled Trial.

    Science.gov (United States)

    Lazarov, Amit; Pine, Daniel S; Bar-Haim, Yair

    2017-07-01

    Patients with social anxiety disorder exhibit increased attentional dwelling on social threats, providing a viable target for therapeutics. This randomized controlled trial examined the efficacy of a novel gaze-contingent music reward therapy for social anxiety disorder designed to reduce attention dwelling on threats. Forty patients with social anxiety disorder were randomly assigned to eight sessions of either gaze-contingent music reward therapy, designed to divert patients' gaze toward neutral stimuli rather than threat stimuli, or to a control condition. Clinician and self-report measures of social anxiety were acquired pretreatment, posttreatment, and at 3-month follow-up. Dwell time on socially threatening faces was assessed during the training sessions and at pre- and posttreatment. Gaze-contingent music reward therapy yielded greater reductions of symptoms of social anxiety disorder than the control condition on both clinician-rated and self-reported measures. Therapeutic effects were maintained at follow-up. Gaze-contingent music reward therapy, but not the control condition, also reduced dwell time on threat, which partially mediated clinical effects. Finally, gaze-contingent music reward therapy, but not the control condition, also altered dwell time on socially threatening faces not used in training, reflecting near-transfer training generalization. This is the first randomized controlled trial to examine a gaze-contingent intervention in social anxiety disorder. The results demonstrate target engagement and clinical effects. This study sets the stage for larger randomized controlled trials and testing in other emotional disorders.

  16. Multisensory aversive stimuli differentially modulate negative feelings in near and far space.

    Science.gov (United States)

    Taffou, Marine; Ondřej, Jan; O'Sullivan, Carol; Warusfel, Olivier; Dubal, Stéphanie; Viaud-Delmon, Isabelle

    2016-05-05

    Affect, space, and multisensory integration are processes that are closely linked. However, it is unclear whether the spatial location of emotional stimuli interacts with multisensory presentation to influence the emotional experience they induce in the perceiver. In this study, we used the unique advantages of virtual reality techniques to present potentially aversive crowd stimuli embedded in a natural context and to control their display in terms of sensory and spatial presentation. Individuals high in crowdphobic fear navigated in an auditory-visual virtual environment, in which they encountered virtual crowds presented through the visual channel, the auditory channel, or both. They reported the intensity of their negative emotional experience at a far distance and at a close distance from the crowd stimuli. Whereas auditory-visual presentation of close feared stimuli amplified negative feelings, auditory-visual presentation of distant feared stimuli did not amplify negative feelings. This suggests that spatial closeness allows multisensory processes to modulate the intensity of the emotional experience induced by aversive stimuli. Nevertheless, the specific role of auditory stimulation must be investigated to better understand this interaction between multisensory, affective, and spatial representation processes. This phenomenon may serve the implementation of defensive behaviors in response to aversive stimuli that are in position to threaten an individual's feeling of security.

  17. VTA glutamatergic inputs to nucleus accumbens drive aversion by acting on GABAergic interneurons

    Science.gov (United States)

    Qi, Jia; Zhang, Shiliang; Wang, Hui-Ling; Barker, David J.; Miranda-Barrientos, Jorge; Morales, Marisela

    2016-01-01

    The ventral tegmental area (VTA) is best known for its dopamine neurons, some of which project to nucleus accumbens (nAcc). However, the VTA also has glutamatergic neurons that project to nAcc. The function of the mesoaccumbens-glutamatergic pathway remains unknown. Here, we report that nAcc photoactivation of mesoaccumbens-glutamatergic fibers promotes aversion. Although we found that these mesoaccumbens-glutamate-fibers lack GABA, the aversion evoked by their photoactivation depends on glutamate and GABA receptor signaling, and not on dopamine receptor signaling. We found that mesoaccumbens-glutamatergic-fibers establish multiple asymmetric synapses on single parvalbumin-GABAergic interneurons, and that nAcc photoactivation of these fibers drives AMPA-mediated cellular firing of parvalbumin-GABAergic interneurons. These parvalbumin-GABAergic-interneurons, in turn, inhibit nAcc medium spiny output neurons, as such, controlling inhibitory neurotransmission within nAcc. The mesoaccumbens-glutamatergic pathway is the first glutamatergic input to nAcc shown to mediate aversion, instead of reward, and the first pathway shown to establish excitatory synapses on nAcc parvalbumin-GABAergic interneurons. PMID:27019014

  18. The intensity of a fetal taste aversion is modulated by the anesthesia used during conditioning.

    Science.gov (United States)

    Mickley, G A; Lovelace, J D; Farrell, S T; Chang, K S

    1995-03-16

    Rat fetuses (E18) can learn a taste aversion in utero if experience with a sweet flavor (saccharin = Sac) is followed by a malaise-producing injection of lithium chloride (LiCl). Here we report that this phenomenon can be significantly modulated by the type of anesthesia administered to the pregnant dam before the conditioning procedure. Dams were anesthetized with one of the following drugs or drug combinations: (1) sodium pentobarbital; (2) ketamine hydrochloride and xylazine; or (3) sodium pentobarbital and ketamine hydrochloride. While under the influence of these anesthetics, rat fetuses received pairings of Sac + LiCl or one of the following sets of oral and systemic (i.p.) control injections: Sac + Saline, H2O + LiCl; H2O + Saline. At age 15 days neonatal rats were given a taste preference test by allowing them to select nipples painted with either saccharin or vehicle (H2O). After weaning, rats were given an additional taste preference test where they were allowed to drink from bottles filled with either 0.30% saccharin or water. Neonates that received Sac + LiCl injections avoided saccharin-painted nipples while neonates that received control injections in utero preferred saccharin-painted nipples. Rats that acquired the taste aversion under the influence of ketamine showed a significantly stronger conditioned taste aversion on the nipple preference test than did those from dams injected with sodium pentobarbital. The conditioned taste aversion was not detectable later during the bottle preference test. Since ketamine blocks N-methyl-D-aspartate (NMDA) glutamate receptors, and these receptors have been implicated in neural plasticity during development, our data suggest that NMDA antagonism can potentiate fetal learning. Ketamine has been used as an obstetrical and pediatric anesthetic.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Equivalence relations and the reinforcement contingency.

    OpenAIRE

    Sidman, M

    2000-01-01

    Where do equivalence relations come from? One possible answer is that they arise directly from the reinforcement contingency. That is to say, a reinforcement contingency produces two types of outcome: (a) 2-, 3-, 4-, 5-, or n-term units of analysis that are known, respectively, as operant reinforcement, simple discrimination, conditional discrimination, second-order conditional discrimination, and so on; and (b) equivalence relations that consist of ordered pairs of all positive elements that...

  20. The Contingent Value of Organizational Integration

    Directory of Open Access Journals (Sweden)

    Virpi Turkulainen

    2013-08-01

    Full Text Available We elaborate the link between organizational design and effectiveness by examining organizational integration and performance in the context of modern manufacturing. Through careful contextualization and empirical analysis of 266 manufacturing organizations in three industries and nine countries, we uncover a joint effect of integration and complexity on organizational effectiveness. The results extend structural contingency theory, in particular the mechanisms that link organizational integration to organizational effectiveness. We conclude by discussing the continuing relevance of structural contingency theory.

  1. Encoding of aversion by dopamine and the nucleus accumbens

    Directory of Open Access Journals (Sweden)

    James Edgar Mccutcheon

    2012-09-01

    Full Text Available Adaptive motivated behavior requires rapid discrimination between beneficial and harmful stimuli. Such discrimination leads to the generation of either an approach or rejection response, as appropriate, and enables organisms to maximize reward and minimize punishment. Classically, the nucleus accumbens (NAc and the dopamine projection to it are considered an integral part of the brain’s reward circuit, i.e., they direct approach and consumption behaviors and underlie positive reinforcement. This reward-centered framing ignores important evidence about the role of this system in encoding aversive events. One reason for bias towards reward is the difficulty in designing experiments in which animals repeatedly experience punishments; another is the challenge in dissociating the response to an aversive stimulus itself from the reward/relief experienced when an aversive stimulus is terminated. Here, we review studies that employ techniques with sufficient time resolution to measure responses in ventral tegmental area (VTA and NAc to aversive stimuli as they are delivered. We also present novel findings showing that the same stimulus – intraoral infusion of sucrose – has differing effects on NAc shell dopamine release depending on the prior experience. Here, for some rats, sucrose was rendered aversive by explicitly pairing it with malaise in a conditioned taste aversion paradigm. Thereafter, sucrose infusions led to a suppression of dopamine with a similar magnitude and time course to intra-oral infusions of a bitter quinine solution. The results are discussed in the context of regional differences in dopamine signaling and the implications of a pause in phasic dopamine release within the NAc shell. Together with our data, the emerging literature suggests an important role for differential phasic dopamine signaling in aversion versus reward.

  2. Encoding of aversion by dopamine and the nucleus accumbens.

    Science.gov (United States)

    McCutcheon, James E; Ebner, Stephanie R; Loriaux, Amy L; Roitman, Mitchell F

    2012-01-01

    Adaptive motivated behavior requires rapid discrimination between beneficial and harmful stimuli. Such discrimination leads to the generation of either an approach or rejection response, as appropriate, and enables organisms to maximize reward and minimize punishment. Classically, the nucleus accumbens (NAc) and the dopamine projection to it are considered an integral part of the brain's reward circuit, i.e., they direct approach and consumption behaviors and underlie positive reinforcement. This reward-centered framing ignores important evidence about the role of this system in encoding aversive events. One reason for bias toward reward is the difficulty in designing experiments in which animals repeatedly experience punishments; another is the challenge in dissociating the response to an aversive stimulus itself from the reward/relief experienced when an aversive stimulus is terminated. Here, we review studies that employ techniques with sufficient time resolution to measure responses in ventral tegmental area and NAc to aversive stimuli as they are delivered. We also present novel findings showing that the same stimulus - intra-oral infusion of sucrose - has differing effects on NAc shell dopamine release depending on the prior experience. Here, for some rats, sucrose was rendered aversive by explicitly pairing it with malaise in a conditioned taste aversion paradigm. Thereafter, sucrose infusions led to a suppression of dopamine with a similar magnitude and time course to intra-oral infusions of a bitter quinine solution. The results are discussed in the context of regional differences in dopamine signaling and the implications of a pause in phasic dopamine release within the NAc shell. Together with our data, the emerging literature suggests an important role for differential phasic dopamine signaling in aversion vs. reward.

  3. 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.

  4. Fractional-moment CAPM with loss aversion

    Energy Technology Data Exchange (ETDEWEB)

    Wu Yahao [Dep. of Math., South China University of Technology, Guangzhou 510640 (China); Wang Xiaotian [Dep. of Math., South China University of Technology, Guangzhou 510640 (China)], E-mail: swa001@126.com; Wu Min [Dep. of Math., South China University of Technology, Guangzhou 510640 (China)

    2009-11-15

    In this paper, we present a new fractional-order value function which generalizes the value function of Kahneman and Tversky [Kahneman D, Tversky A. Prospect theory: an analysis of decision under risk. Econometrica 1979;47:263-91; Tversky A, Kahneman D. Advances in prospect theory: cumulative representation of uncertainty. J. Risk Uncertainty 1992;4:297-323], and give the corresponding fractional-moment versions of CAPM in the cases of both the prospect theory [Kahneman D, Tversky A. Prospect theory: an analysis of decision under risk. Econometrica 1979;47:263-91; Tversky A, Kahneman D. Advances in prospect theory: cumulative representation of uncertainty. J. Risk Uncertainty 1992;4:297-323] and the expected utility model. The models that we obtain can be used to price assets when asset return distributions are likely to be asymmetric stable Levy distribution during panics and stampedes in worldwide security markets in 2008. In particular, from the prospect theory we get the following fractional-moment CAPM with loss aversion: E(R{sub i}-R{sub 0})=(E[(W-W{sub 0}){sub +}{sup -0.12}(R{sub i}-R{sub 0})]+2.25E[(W{sub 0}-W){sub +}{sup -0.12}(R{sub i}-R{sub 0})])/ (E[(W-W{sub 0}){sub +}{sup -0.12} (W-R{sub 0})]+2.25E[(W{sub 0}-W){sub +}{sup -0.12}(W-R{sub 0})]) .E(W-R{sub 0}), where W{sub 0} is a fixed reference point distinguishing between losses and gains.

  5. Aversion norm, replacing in the poem siab

    Directory of Open Access Journals (Sweden)

    Ebrahim Namdari

    2014-03-01

    Full Text Available Aversion norm or DE familiarization is a term that formalists it was first introduced. They believe that the work of art, not automatic and amazing things to see is that, because of things after a while, replication of us are normal, so do not see it. We poetic language, we are faced with a fundamental change in the relationship between signifier and signified, i.e. Familiar language, signifiers, signified by certain, but the poetic language signifier, the signified can be found in the pelvis, and the audience to understand the signified a new, hard falls, and the longer perceived to be, and where it refers to the discovery, after some hesitation, more enjoyable, the audience will have a special effect. 's poetic language, the beauty side implicated in emotional and motivational speaking, hiding the core meaning of the word, and indeed with the usual meaning and familiar DE familiarization, are shown. Beauty in ordinary language, they do not see, thus implying that subtle poet highlighting the special meaning of the word in ordinary language is different, the vocabulary word meanings change, and where it is meant to transform Familiar word, because the audience is emotionally motivated, it is more effective. The poet does not read words into their common name, but it so describes it as if for the first time we've seen. Word to describe him, sometimes uses the common name of its components, and metonymy create, and sometimes it does not use the common name of its components, but another word to call it, uses, and in fact the word it brings a different metaphor, and thus far is the common standard language, new language makes.

  6. Strategy as Mutually Contingent Choice

    Directory of Open Access Journals (Sweden)

    Neil Martin

    2016-05-01

    Full Text Available Thomas Schelling’s The Strategy of Conflict carries significant behavioral implications which have been overlooked by economic readers. I argue that these implications are central to Schelling’s vision of game theory, that they fit well with recent advances in experimental psychology and behavioral economics, and provide a comprehensive framework that can inform research on strategy. In my view, Schelling develops a non-mathematical approach to strategy which anticipates on Gigerenzer and Selten’s “ecological rationality” program. This approach maps the processes involved in strategic reasoning and highlights their reliance on the particular information structure of interactive social environments. Building on this approach, I model strategy as a heuristic form of reasoning that governs the way in which individuals search for and provide cues in situations of mutually contingent choice. I conclude by examining how the reference to ecological rationality can help clarify Schelling’s contribution to game theory and outline potential avenues of research into strategic reasoning and interaction.

  7. Aversive counterconditioning attenuates reward signalling in the ventral striatum

    Directory of Open Access Journals (Sweden)

    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.

  8. Risk-Averse Newsvendor Model with Strategic Consumer Behavior

    Directory of Open Access Journals (Sweden)

    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.

  9. Differences in risk aversion between young and older adults

    Directory of Open Access Journals (Sweden)

    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

  10. RELATIONSHIP BETWEEN THE TASK AVERSIVENESS AND ACADEMIC PROCRASTINATION

    Directory of Open Access Journals (Sweden)

    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.

  11. Appetitive-aversive interactions in Pavlovian fear conditioning.

    Science.gov (United States)

    Nasser, Helen M; McNally, Gavan P

    2012-06-01

    The existence of value coding and salience coding neurons in the mammalian brain, including in habenula and ventral tegmental area, has sparked considerable interest in the interactions that occur between Pavlovian appetitive and aversive conditioning. Here we studied these appetitive-aversive interactions at the behavioral level by assessing the learning that occurs when a Pavlovian appetitive conditioned stimulus (conditional stimulus, CS) serves as a CS for shock in Pavlovian fear conditioning. A Pavlovian appetitive CS was retarded in the rate at which it could be transformed into a fear CS (counterconditioning), but the presence of the appetitive CS augmented fear learning to a concurrently presented neutral CS (superconditioning). Retardation of fear learning was not alleviated by manipulations designed to restore the associability of the appetitive CS before fear conditioning but was alleviated by manipulations designed to increase the aversive quality of the shock unconditioned stimulus (US). These findings are consistent with opponent interactions between the appetitive and aversive motivational systems and provide a behavioral approach for assessing the neural correlates of these appetitive-aversive interactions.

  12. 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...... with individual differences in loss aversion. Together, the results show that the amygdala signals subjective appetitiveness or aversiveness of gain-loss ratios at the time of choice. (C) 2015 Elsevier Ltd. All rights reserved....... 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...

  13. Food cravings, aversions and pica among pregnant women in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Nyaruhucha, C N M

    2009-01-01

    Food cravings, aversions and pica are common during pregnancy and may have a significant input on pregnancy progress and outcome. A study was carried out to determine the frequency and duration of pronounced dietary cravings, aversions and pica during pregnancy among 204 pregnant and lactating women attending two health facilities in Dar es Salaam City, Tanzania. Nausea and vomiting were reported by 82.8% of all women of which 43.2% experienced severe nausea alone, 9.5% severe vomiting alone and 35.5% experienced severe vomiting and nausea. Mild cases of each of the symptoms either occurring alone or both of them occurring together were also reported. Both behaviours were observed more in pregnancy. The proportions of women with dietary cravings, aversions, and pica were 73.5%, 70.1% and 63.7% of all women respectively. More women (70.1%) experienced both food cravings and aversions than either symptom alone. Foods craved most were meat (23.3%), mangoes (22.7%), yoghurt (20.0%) oranges (20.0%), plantain (15.3%) and soft drinks (13.3%). Foods avoided most were rice (36.4%), meat (36.4%) and fish (30.8%). Eggs, beans, tea and stiff porridge were also avoided. Reasons given for avoiding foods were unpleasant smell/taste (10.3%), to reduce nausea (11.8%), no particular reason (58.3%) and dislike by foetus (belief) (3.9%). Pica was experienced by 63.7%% of the women and soil, ice and ash were the most commonly non-food substances eaten. The frequency of nausea and vomiting was highest in the early months of pregnancy and most women experienced the symptoms during morning hours. Craving in most women was more intense in the first trimesters. Most women craved for meat and sour and savoury foods, and avoided rice, meat and fish. Soil consumption was the pica observed in most women. Since aversions and cravings are closely linked to dietary intake of pregnant woman understanding these behaviours is important in addressing maternal nutrition.

  14. ACCRUAL OF LIABILITIES AND CONTINGENT ASSETS

    Directory of Open Access Journals (Sweden)

    Elena Ilie

    2011-12-01

    Full Text Available International Financial Reporting Standards together with Public Sector Accounting Standards are based on professional reasoning by appealing to principles that can lead to several solutions for a certain problem. In this respect Romanian economic mechanisms have a high level of rigidity in the implementation of accounting concepts and principles so that it is important to highlight the aspects that generate added value in the current economic climate. Even since 2005 the harmonization of Romanian accounting with the directives of International Accounting Standards, which came to support the harmonization of rules and principles concerning the development of annual financial statements of public institutions, is the most important and essential challenge for administrative environment. Assets and contingent liabilities are elements which in terms of the law cannot be included in the assets of a public institution that is why accounting of these elements must be performed using special off-balance sheet accounts. The purpose of this work emphasizes the opportunity and the recognition of economic events whose elements should be reflected in balance sheet, but also the appropriate and necessary moment of making entries over special accounts off the balance sheet in accordance with IPSAS 19.

  15. Optimal self-esteem is contingent: Intrinsic versus extrinsic and upward versus downward contingencies

    NARCIS (Netherlands)

    Vonk, R.; Smit, H.M.M.

    2012-01-01

    We argue that noncontingent, unconditional self-esteem is not optimal but defensive. We introduce the concept of intrinsic contingency, where self-esteem is affected by whether one's actions are self-congruent and conducive to personal growth. Whereas external contingencies, especially social and ap

  16. Effect of yohimbine on reinstatement of operant responding in rats is dependent on cue contingency but not food reward history.

    Science.gov (United States)

    Chen, Yu-Wei; Fiscella, Kimberly A; Bacharach, Samuel Z; Tanda, Gianluigi; Shaham, Yavin; Calu, Donna J

    2015-07-01

    Yohimbine is an alpha-2 adrenoceptor antagonist that has been used in numerous studies as a pharmacological stressor in rodents, monkeys and humans. Recently, yohimbine has become the most common stress manipulation in studies on reinstatement of drug and food seeking. However, the wide range of conditions under which yohimbine promotes reward seeking is significantly greater than that of stressors like intermittent footshock. Here, we addressed two fundamental questions regarding yohimbine's effect on reinstatement of reward seeking: (1) whether the drug's effect on operant responding is dependent on previous reward history or cue contingency, and (2) whether yohimbine is aversive or rewarding under conditions typically used in reinstatement studies. We also used in vivo microdialysis to determine yohimbine's effect on dopamine levels in nucleus accumbens (NAc) and medial prefrontal cortex (mPFC). We found that the magnitude of yohimbine-induced (0.5, 1.0, 2.0 mg/kg) operant responding during the reinstatement tests was critically dependent on the contingency between lever pressing and discrete tone-light cue delivery but not the previous history with food reward during training. We also found that yohimbine (2 mg/kg) did not cause conditioned place aversion. Finally, we found that yohimbine modestly increased dopamine levels in mPFC but not NAc. Results suggest that yohimbine's effects on operant responding in reinstatement studies are likely independent of the history of contingent self-administration of food or drug rewards and may not be related to the commonly assumed stress-like effects of yohimbine.

  17. Learning the way to blood: first evidence of dual olfactory conditioning in a blood-sucking insect, Rhodnius prolixus. II. Aversive learning.

    Science.gov (United States)

    Vinauger, Clément; Buratti, Laura; Lazzari, Claudio R

    2011-09-15

    After having demonstrated that blood-sucking bugs are able to associate a behaviourally neutral odour (L-lactic acid) with positive reinforcement (i.e. appetitive conditioning) in the first part of this study, we tested whether these insects were also able to associate the same odour with a negative reinforcement (i.e. aversive conditioning). Learned aversion to host odours has been repeatedly suggested as a determinant for the distribution of disease vectors among host populations. Nevertheless, no experimental evidence has been obtained so far. Adapting a classical conditioning approach to our haematophagous model, we trained larvae of Rhodnius prolixus to associate L-lactic acid, an odour perceived by bugs but behaviourally neutral when presented alone, with a mechanical perturbation (i.e. negative reinforcement). Naive bugs and bugs exposed to CS, punishment, or CS and punishment without contingency remained indifferent to the presence of an air stream loaded with L-lactic acid (random orientation on a locomotion compensator), whereas the groups previously exposed to the contingency CS-punishment were significantly repelled by L-lactic acid. In a companion paper, the opposite, i.e. attraction, was induced in bugs exposed to the contingency of the same odour with a positive reinforcement. These constitute the first pieces of evidence of olfactory conditioning in triatomine bugs and the first demonstration that the same host odour can be used by insects that are disease vectors to learn to recognize either a host to feed on or a potentially defensive one. The orientation mechanism during repulsion is also discussed in light of our results.

  18. Contingency Contractor Optimization Phase 3 Sustainment Software Design Document - Contingency Contractor Optimization Tool - Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Durfee, Justin David; Frazier, Christopher Rawls; Bandlow, Alisa; Jones, Katherine A

    2016-05-01

    This document describes the final software design of the Contingency Contractor Optimization Tool - Prototype. Its purpose is to provide the overall architecture of the software and the logic behind this architecture. Documentation for the individual classes is provided in the application Javadoc. The Contingency Contractor Optimization project is intended to address Department of Defense mandates by delivering a centralized strategic planning tool that allows senior decision makers to quickly and accurately assess the impacts, risks, and mitigation strategies associated with utilizing contract support. The Contingency Contractor Optimization Tool - Prototype was developed in Phase 3 of the OSD ATL Contingency Contractor Optimization project to support strategic planning for contingency contractors. The planning tool uses a model to optimize the Total Force mix by minimizing the combined total costs for selected mission scenarios. The model optimizes the match of personnel types (military, DoD civilian, and contractors) and capabilities to meet mission requirements as effectively as possible, based on risk, cost, and other requirements.

  19. Conditioned taste aversion, drugs of abuse and palatability

    Science.gov (United States)

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

    2014-01-01

    LIN, J.-Y., J. Arthurs and S. Reilly. Conditioned taste aversion: Palatability and drugs of abuse. NEUROSCI BIOBEHAV REV XX(x) XXX-XXX, 2014. – 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. PMID:24813806

  20. Use of risk aversion in risk acceptance criteria

    Energy Technology Data Exchange (ETDEWEB)

    Griesmeyer, J. M.; Simpson, M.; Okrent, D.

    1980-06-01

    Quantitative risk acceptance criteria for technological systems must be both justifiable, based upon societal values and objectives, and workable in the sense that compliance is possible and can be demonstrated in a straightforward manner. Societal values have frequently been assessed using recorded accident statistics on a wide range of human activities assuming that the statistics in some way reflect societal preferences, or by psychometric surveys concerning perceptions and evaluations of risk. Both methods indicate a societal aversion to risk e.g., many small accidents killing a total of 100 people are preferred over one large accident in which 100 lives are lost. Some of the implications of incorporating risk aversion in acceptance criteria are discussed. Calculated risks of various technological systems are converted to expected social costs using various risk aversion factors. The uncertainties in these assessments are also discussed.

  1. Shared risk aversion in spontaneous and induced abortion

    DEFF Research Database (Denmark)

    Catalano, Ralph; Bruckner, Tim A.; Karasek, Deborah

    2016-01-01

    STUDY QUESTION: 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? SUMMARY ANSWER: 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. WHAT IS KNOWN ALREADY: Much literature speculates that natural selection conserved risk aversion because the trait enhanced Darwinian fitness. Risk...... and spontaneous abortion over time. STUDY DESIGN, SIZE, DURATION: 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...

  2. 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.

  3. Risk Aversion and Engagement in the Sharing Economy

    OpenAIRE

    Jessica Santana; Paolo Parigi

    2015-01-01

    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 wit...

  4. Color and Contingency in Robert Boyle's Works.

    Science.gov (United States)

    Baker, Tawrin

    2015-01-01

    This essay investigates the relationship between color and contingency in Robert Boyle's Experiments and Considerations Touching Colours (1664) and his essays on the unsuccessfulness of experiments in Certain Physiological Essays (1661). In these two works Boyle wrestles with a difficult practical and philosophical problem with experiments, which he calls the problem of contingency. In Touching Colours, the problem of contingency is magnified by the much-debated issue of whether color had any deep epistemic importance. His limited theoretical principle guiding him in Touching Colours, that color is but modified light, further exacerbated the problem. Rather than theory, Boyle often relied on craftsmen, whose mastery of color phenomena was, Boyle mentions, brought about by economic forces, to determine when colors were indicators of important 'inward' properties of substances, and thus to secure a solid foundation for his experimental history of color.

  5. Equivalence relations and the reinforcement contingency.

    Science.gov (United States)

    Sidman, M

    2000-07-01

    Where do equivalence relations come from? One possible answer is that they arise directly from the reinforcement contingency. That is to say, a reinforcement contingency produces two types of outcome: (a) 2-, 3-, 4-, 5-, or n-term units of analysis that are known, respectively, as operant reinforcement, simple discrimination, conditional discrimination, second-order conditional discrimination, and so on; and (b) equivalence relations that consist of ordered pairs of all positive elements that participate in the contingency. This conception of the origin of equivalence relations leads to a number of new and verifiable ways of conceptualizing equivalence relations and, more generally, the stimulus control of operant behavior. The theory is also capable of experimental disproof.

  6. 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…

  7. 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…

  8. 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…

  9. Estimating state-contingent production functions

    DEFF Research Database (Denmark)

    Rasmussen, Svend; Karantininis, Kostas

    The paper reviews the empirical problem of estimating state-contingent production functions. The major problem is that states of nature may not be registered and/or that the number of observation per state is low. Monte Carlo simulation is used to generate an artificial, uncertain production...... environment based on Cobb Douglas production functions with state-contingent parameters. The pa-rameters are subsequently estimated based on different sizes of samples using Generalized Least Squares and Generalized Maximum Entropy and the results are compared. It is concluded that Maximum Entropy may...

  10. A contingency table approach to nonparametric testing

    CERN Document Server

    Rayner, JCW

    2000-01-01

    Most texts on nonparametric techniques concentrate on location and linear-linear (correlation) tests, with less emphasis on dispersion effects and linear-quadratic tests. Tests for higher moment effects are virtually ignored. Using a fresh approach, A Contingency Table Approach to Nonparametric Testing unifies and extends the popular, standard tests by linking them to tests based on models for data that can be presented in contingency tables.This approach unifies popular nonparametric statistical inference and makes the traditional, most commonly performed nonparametric analyses much more comp

  11. Solution aversion: On the relation between ideology and motivated disbelief.

    Science.gov (United States)

    Campbell, Troy H; Kay, Aaron C

    2014-11-01

    There is often a curious distinction between what the scientific community and the general population believe to be true of dire scientific issues, and this skepticism tends to vary markedly across groups. For instance, in the case of climate change, Republicans (conservatives) are especially skeptical of the relevant science, particularly when they are compared with Democrats (liberals). What causes such radical group differences? We suggest, as have previous accounts, that this phenomenon is often motivated. However, the source of this motivation is not necessarily an aversion to the problem, per se, but an aversion to the solutions associated with the problem. This difference in underlying process holds important implications for understanding, predicting, and influencing motivated skepticism. In 4 studies, we tested this solution aversion explanation for why people are often so divided over evidence and why this divide often occurs so saliently across political party lines. Studies 1, 2, and 3-using correlational and experimental methodologies-demonstrated that Republicans' increased skepticism toward environmental sciences may be partly attributable to a conflict between specific ideological values and the most popularly discussed environmental solutions. Study 4 found that, in a different domain (crime), those holding a more liberal ideology (support for gun control) also show skepticism motivated by solution aversion.

  12. Context Dependency of Conditioned Aversions to Familiar and Novel Fluids

    Science.gov (United States)

    Ishii, Kiyoshi; Iguchi, Yoshio; Sawa, Kosuke

    2006-01-01

    Using a context discrimination procedure and rats as the subjects, the formation of context-dependent aversions to novel and familiar fluids was investigated. Experiment 1 revealed that context dependency could be established to a novel fluid (saccharin) after three cycles of context discrimination training and that the acquired context dependency…

  13. 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.

  14. Joint measurement of risk aversion, prudence, and temperance

    NARCIS (Netherlands)

    Ebert, S.; Wiesen, D.

    2014-01-01

    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 compensat

  15. 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

  16. 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

  17. An Aversive Response to Osmotic Upshift in Caenorhabditis elegans.

    Science.gov (United States)

    Yu, Jingyi; Yang, Wenxing; Liu, He; Hao, Yingsong; Zhang, Yun

    2017-01-01

    Environmental osmolarity presents a common type of sensory stimulus to animals. While behavioral responses to osmotic changes are important for maintaining a stable intracellular osmolarity, the underlying mechanisms are not fully understood. In the natural habitat of Caenorhabditis elegans, changes in environmental osmolarity are commonplace. It is known that the nematode acutely avoids shocks of extremely high osmolarity. Here, we show that C. elegans also generates gradually increased aversion of mild upshifts in environmental osmolarity. Different from an acute avoidance of osmotic shocks that depends on the function of a transient receptor potential vanilloid channel, the slow aversion to osmotic upshifts requires the cGMP-gated sensory channel subunit TAX-2. TAX-2 acts in several sensory neurons that are exposed to body fluid to generate the aversive response through a motor network that underlies navigation. Osmotic upshifts activate the body cavity sensory neuron URX, which is known to induce aversion upon activation. Together, our results characterize the molecular and cellular mechanisms underlying a novel sensorimotor response to osmotic stimuli and reveal that C. elegans engages different behaviors and the underlying mechanisms to regulate responses to extracellular osmolarity.

  18. Ambiguity Aversion and Household Portfolio Choice Puzzles: Empirical Evidence

    NARCIS (Netherlands)

    S.G. Dimmock (Stephen); R.R.P. Kouwenberg (Roy); O.S. Mitchell (Olivia); K. Peijnenburg (Kim)

    2016-01-01

    markdownabstractWe 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 ambig

  19. 21 CFR 882.5235 - Aversive conditioning device.

    Science.gov (United States)

    2010-04-01

    ... electrical shock or other noxious stimulus to a patient to modify undesirable behavioral characteristics. (b... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Aversive conditioning device. 882.5235 Section 882.5235 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  20. The risk-averse newsvendor problem with random capacity

    NARCIS (Netherlands)

    Wu, Meng; Zhu, Stuart X.; Teunter, Ruud H.

    2013-01-01

    We study the effect of capacity uncertainty on the inventory decisions of a risk-averse newsvendor. We consider two well-known risk criteria, namely Value-at-Risk (VaR) included as a constraint and Conditional Value-at-Risk (CVaR). For the risk-neutral newsvendor, we find that the optimal order quan

  1. 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.

  2. The risk-averse newsvendor problem with random capacity

    NARCIS (Netherlands)

    Wu, Meng; Zhu, Stuart X.; Teunter, Ruud H.

    2013-01-01

    We study the effect of capacity uncertainty on the inventory decisions of a risk-averse newsvendor. We consider two well-known risk criteria, namely Value-at-Risk (VaR) included as a constraint and Conditional Value-at-Risk (CVaR). For the risk-neutral newsvendor, we find that the optimal order

  3. Loss Aversion with a State-dependent Reference Point

    NARCIS (Netherlands)

    E.G. De Georgi (Enrico); G.T. Post (Thierry)

    2008-01-01

    textabstractThis study investigates loss aversion when the reference point is state-dependent. Using a state-dependent structure, prospects are more attractive if they depend positively on the reference point and are less attractive in case of negative dependence. In addition, the structure is neutr

  4. ABA, AAB and ABC Renewal in Taste Aversion Learning

    Science.gov (United States)

    Bernal-Gamboa, Rodolfo; Juarez, Yectivani; Gonzalez-Martin, Gabriela; Carranza, Rodrigo; Sanchez-Carrasco, Livia; Nieto, Javier

    2012-01-01

    Context renewal is identified when the conditioned response (CR) elicited by an extinguished conditioned stimulus (CS) reappears as a result of changing the contextual cues during the test. Two experiments were designed for testing contextual renewal in a conditioned taste aversion preparation. Experiment 1 assessed ABA and AAB context renewal,…

  5. Counterfactual Reasoning for Regretted Situations Involving Controllable Versus Uncontrollable Events: The Modulating Role of Contingent Self-Esteem

    OpenAIRE

    2015-01-01

    We report a study that examined the modulating impact of contingent self-esteem on regret\\ud intensity for regretted outcomes associated with controllable versus uncontrollable events.\\ud The Contingent Self-Esteem Scale (e.g., Kernis & Goldman, 2006) was used to assess the extent\\ud to which a person’s sense of self-worth is based on self and others’ expectations. We found\\ud that there was an influence of self-esteem contingency for controllable but not for uncontrollable\\ud regret types. F...

  6. Reappraising social insect behavior through aversive responsiveness and learning.

    Directory of Open Access Journals (Sweden)

    Edith Roussel

    Full Text Available BACKGROUND: 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. METHODOLOGY: 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. PRINCIPAL FINDINGS: 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. CONCLUSIONS: Our results constitute the first integrative

  7. Ottawa National Wildlife Refuge : Energy Emergency Contingency Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is the Energy Emergency Contingency Plan for Ottawa National Wildlife Refuge. The Ottawa National Wildlife Refuge Energy Emergency Contingency Plan outlines...

  8. Contingency Contractor Optimization Phase 3 Sustainment Third-Party Software List - Contingency Contractor Optimization Tool - Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Durfee, Justin David; Frazier, Christopher Rawls; Bandlow, Alisa

    2016-05-01

    The Contingency Contractor Optimization Tool - Prototype (CCOT-P) requires several third-party software packages. These are documented below for each of the CCOT-P elements: client, web server, database server, solver, web application and polling application.

  9. Contingency Management and Stuttering in Children

    Science.gov (United States)

    Ryan, Bruce P.

    2004-01-01

    This is a review of the contingency management literature and current related treatment programs for stuttering in childhood: the Lidcombe Program, Gradual Increase in Length and Complexity of Utterance (GILCU), and Prolongation (PS). Treatment efficacy research has shown these treatments to be effective and efficient for children, but there…

  10. The Contingent Valuation Method in Public Libraries

    Science.gov (United States)

    Chung, Hye-Kyung

    2008-01-01

    This study aims to present a new model measuring the economic value of public libraries, combining the dissonance minimizing (DM) and information bias minimizing (IBM) format in the contingent valuation (CV) surveys. The possible biases which are tied to the conventional CV surveys are reviewed. An empirical study is presented to compare the model…

  11. Modeling and simulation of cascading contingencies

    Science.gov (United States)

    Zhang, Jianfeng

    This dissertation proposes a new approach to model and study cascading contingencies in large power systems. The most important contribution of the work involves the development and validation of a heuristic analytic model to assess the likelihood of cascading contingencies, and the development and validation of a uniform search strategy. We model the probability of cascading contingencies as a function of power flow and power flow changes. Utilizing logistic regression, the proposed model is calibrated using real industry data. This dissertation analyzes random search strategies for Monte Carlo simulations and proposes a new uniform search strategy based on the Metropolis-Hastings Algorithm. The proposed search strategy is capable of selecting the most significant cascading contingencies, and it is capable of constructing an unbiased estimator to provide a measure of system security. This dissertation makes it possible to reasonably quantify system security and justify security operations when economic concerns conflict with reliability concerns in the new competitive power market environment. It can also provide guidance to system operators about actions that may be taken to reduce the risk of major system blackouts. Various applications can be developed to take advantage of the quantitative security measures provided in this dissertation.

  12. The dependency and contingency of politics

    DEFF Research Database (Denmark)

    Triantafillou, Peter

    2016-01-01

    differences which make any analytical synthesis both a difficult and a questionable endeavour. In particular, whereas historical institutionalism seeks to explain the present in terms of its dependence on past events, genealogy seeks to provoke the present by demonstrating its historical contingency. In spite...

  13. If -Then Contingencies in Children's Sibling Conflicts

    Science.gov (United States)

    Perlman, Michal; Ross, Hildy S.

    2005-01-01

    Two-step (if -then) behavioral contingencies in the naturally occurring conflicts of 2- and 4-year-old siblings were identified and described. Children's crying, compliance, ignoring, opposition, power, and reasoning strategies were examined to determine how they were used immediately following opposition, power, and reasoning from siblings and…

  14. Neural Events in the Reinforcement Contingency

    Science.gov (United States)

    Silva, Maria Teresa Araujo; Goncalves, Fabio Leyser; Garcia-Mijares, Miriam

    2007-01-01

    When neural events are analyzed as stimuli and responses, functional relations among them and among overt stimuli and responses can be unveiled. The integration of neuroscience and the experimental analysis of behavior is beginning to provide empirical evidence of involvement of neural events in the three-term contingency relating discriminative…

  15. Visual Analytics for Power Grid Contingency Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Pak C.; Huang, Zhenyu; Chen, Yousu; Mackey, Patrick S.; Jin, Shuangshuang

    2014-01-20

    Contingency analysis is the process of employing different measures to model scenarios, analyze them, and then derive the best response to remove the threats. This application paper focuses on a class of contingency analysis problems found in the power grid management system. A power grid is a geographically distributed interconnected transmission network that transmits and delivers electricity from generators to end users. The power grid contingency analysis problem is increasingly important because of both the growing size of the underlying raw data that need to be analyzed and the urgency to deliver working solutions in an aggressive timeframe. Failure to do so may bring significant financial, economic, and security impacts to all parties involved and the society at large. The paper presents a scalable visual analytics pipeline that transforms about 100 million contingency scenarios to a manageable size and form for grid operators to examine different scenarios and come up with preventive or mitigation strategies to address the problems in a predictive and timely manner. Great attention is given to the computational scalability, information scalability, visual scalability, and display scalability issues surrounding the data analytics pipeline. Most of the large-scale computation requirements of our work are conducted on a Cray XMT multi-threaded parallel computer. The paper demonstrates a number of examples using western North American power grid models and data.

  16. Towards a contingency theory of Operations Management

    DEFF Research Database (Denmark)

    Boer, Harry; Boer, Henrike Engele Elisabeth; Demeter, Krisztina

    2017-01-01

    This paper presents an analysis of papers addressing relationships between context, OM practice and performance, published in IJOPM and JOM over the last 25 years. The analysis suggest that the field is highly scattered, still quite immature, but growing. Suggestions for further analysis of exist...... of existing, and directions for future, research are formulated, aimed at furthering the development of OM contingency theory....

  17. The Contingent Valuation Method in Public Libraries

    Science.gov (United States)

    Chung, Hye-Kyung

    2008-01-01

    This study aims to present a new model measuring the economic value of public libraries, combining the dissonance minimizing (DM) and information bias minimizing (IBM) format in the contingent valuation (CV) surveys. The possible biases which are tied to the conventional CV surveys are reviewed. An empirical study is presented to compare the model…

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

    Directory of Open Access Journals (Sweden)

    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.

  19. Transdiagnostic Psychiatric Symptoms and Event-Related Potentials following Rewarding and Aversive Outcomes

    Science.gov (United States)

    Bedwell, Jeffrey S.; Potts, Geoffrey F.; Gooding, Diane C.; Trachik, Benjamin J.; Chan, Chi C.; Spencer, Christopher C.

    2016-01-01

    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. PMID:27299996

  20. 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.

  1. 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.

  2. 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....... The results reflect two reasons for the high betting rate: initial tendency to participate and slow learning. Under certain conditions, the observed betting rate was higher than the rate predicted under random choice even after 250 trials with immediate feedback. These results can be captured with a model...

  3. 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.

  4. 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.

  5. 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

  6. Lateral Habenula determines long-term storage of aversive memories

    Science.gov (United States)

    Tomaiuolo, Micol; Gonzalez, Carolina; Medina, Jorge H.; Piriz, Joaquin

    2014-01-01

    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 h 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. PMID:24860453

  7. Modeling Inequity Aversion in a Dictator Game with Production

    Directory of Open Access Journals (Sweden)

    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.

  8. 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.

  9. ‘Too many girls, too much dowry’: son preference and daughter aversion in rural Tamil Nadu, India

    Science.gov (United States)

    DIAMOND-SMITH, NADIA; LUKE, NANCY; MCGARVEY, STEPHEN

    2013-01-01

    The southern Indian state of Tamil Nadu has experienced a dramatic decline in fertility, accompanied by a trend of increased son preference. This paper reports on findings from qualitative interviews with women in rural villages about their fertility decision-making. Specifically addressed are the reasons behind increasing son preference and the consequences of this change. Findings suggest that daughter aversion, fuelled primarily by the perceived economic burden of daughters due to the proliferation of dowry, is playing a larger role in fertility decision-making than son preference. The desire for a son is often trumped by the worry over having many daughters. Women use various means of controlling the sex of their children, which in this study appear to be primarily female infanticide. It is important to distinguish between son preference and daughter aversion and to examine repercussions of low fertility within this setting. PMID:18821352

  10. A Group Contingency Program to Improve the Behavior of Elementary School Students in a Cafeteria

    Science.gov (United States)

    Fabiano, Gregory A.; Pelham, William E., Jr.; Karmazin, Karen; Kreher, Joanne; Panahon, Carlos J.; Carlson, Carl

    2008-01-01

    Studies of behavior modification interventions for disruptive behavior in schools have generally focused on classroom behavior with less research directed toward child behavior in other school settings (e.g., cafeterias). The present report documents the effect of a group contingency intervention with a random reward component, targeting…

  11. Estimating the Willingness to Pay for the Benefit of AES Using the Contingent Valuation Method

    NARCIS (Netherlands)

    Haile, D.T.; Slangen, L.H.G.

    2009-01-01

    This paper presents results of a contingent valuation study based on responses from household members living in Winterswijk, The Netherlands. The respondents are asked to report their preferences on a range of willingness to pay (WTP) for agri-environmental schemes (AES) provided by farmers. Estimat

  12. Assessing the Feasibility of Using Contingency Management to Modify Cigarette Smoking by Adolescents

    Science.gov (United States)

    Roll, John M.

    2005-01-01

    Cigarette smoking is a leading cause of preventable death in the United States. Many smokers initiate this dangerous behavior during adolescence. This report describes a contingency management intervention designed to initate and maintain a period of abstinence from cigarettes by adolescent smokers. Results suggest that the intervention was…

  13. Assessing the Feasibility of Using Contingency Management to Modify Cigarette Smoking by Adolescents

    Science.gov (United States)

    Roll, John M.

    2005-01-01

    Cigarette smoking is a leading cause of preventable death in the United States. Many smokers initiate this dangerous behavior during adolescence. This report describes a contingency management intervention designed to initate and maintain a period of abstinence from cigarettes by adolescent smokers. Results suggest that the intervention was…

  14. 76 FR 57661 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List

    Science.gov (United States)

    2011-09-16

    ... relations, Penalties, Reporting and recordkeeping requirements, Superfund, Water pollution control, Water... AGENCY 40 CFR Part 300 National Oil and Hazardous Substances Pollution Contingency Plan; National..., Texas 75202-2733; Hours of operation: Monday thru Friday, 9 a.m. to 12 p.m. and 1 to 4 p.m. Contact...

  15. 76 FR 57702 - National Oil and Hazardous Substances Pollution Contingency Plan National Priorities List

    Science.gov (United States)

    2011-09-16

    ..., Intergovernmental relations, Penalties, Reporting and recordkeeping requirements, Superfund, Water pollution control... AGENCY 40 CFR Part 300 National Oil and Hazardous Substances Pollution Contingency Plan National..., Texas 75202-2733; Hours of operation: Monday thru Friday, 9 a.m. to 12 p.m. and 1 p.m. to 4 p.m. Contact...

  16. A Group Contingency Program to Improve the Behavior of Elementary School Students in a Cafeteria

    Science.gov (United States)

    Fabiano, Gregory A.; Pelham, William E., Jr.; Karmazin, Karen; Kreher, Joanne; Panahon, Carlos J.; Carlson, Carl

    2008-01-01

    Studies of behavior modification interventions for disruptive behavior in schools have generally focused on classroom behavior with less research directed toward child behavior in other school settings (e.g., cafeterias). The present report documents the effect of a group contingency intervention with a random reward component, targeting…

  17. Assessing the Warm Glow Effect in Contingent Valuations for Public Libraries

    Science.gov (United States)

    Lee, Soon-Jae; Chung, Hye-Kyung; Jung, Eun-Joo

    2010-01-01

    This article aims to present evidence of the warm glow effect in a public library setting. More specifically, it tests whether individual respondents with different values for the warm glow component report different values for their willingness to pay (WTP). The data come from a contingent valuation survey conducted on randomly selected citizens…

  18. Assessing the Warm Glow Effect in Contingent Valuations for Public Libraries

    Science.gov (United States)

    Lee, Soon-Jae; Chung, Hye-Kyung; Jung, Eun-Joo

    2010-01-01

    This article aims to present evidence of the warm glow effect in a public library setting. More specifically, it tests whether individual respondents with different values for the warm glow component report different values for their willingness to pay (WTP). The data come from a contingent valuation survey conducted on randomly selected citizens…

  19. 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.

  20. Three dopamine pathways induce aversive odor memories with different stability.

    Directory of Open Access Journals (Sweden)

    Yoshinori Aso

    Full Text Available Animals acquire predictive values of sensory stimuli through reinforcement. In the brain of Drosophila melanogaster, activation of two types of dopamine neurons in the PAM and PPL1 clusters has been shown to induce aversive odor memory. Here, we identified the third cell type and characterized aversive memories induced by these dopamine neurons. These three dopamine pathways all project to the mushroom body but terminate in the spatially segregated subdomains. To understand the functional difference of these dopamine pathways in electric shock reinforcement, we blocked each one of them during memory acquisition. We found that all three pathways partially contribute to electric shock memory. Notably, the memories mediated by these neurons differed in temporal stability. Furthermore, combinatorial activation of two of these pathways revealed significant interaction of individual memory components rather than their simple summation. These results cast light on a cellular mechanism by which a noxious event induces different dopamine signals to a single brain structure to synthesize an aversive memory.

  1. 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.

  2. Insensitivity to Scope in Contingent Valuation Studies

    DEFF Research Database (Denmark)

    Søgaard, Rikke; Lindholt, Jes Sanddal; Gyrd-Hansen, Dorte

    2012-01-01

    insensitivity and to assess the relevance of potential explanations that may help to shed light on how to appropriately handle this problem in contingent valuation studies. Methods: We surveyed a sample of 2004 men invited for cardiovascular disease screening. Each respondent had three contingent valuation...... tasks from which their sensitivity to larger risk reductions (test 1) and to change in travel costs associated with participation (test 2) could be assessed. Participants were surveyed while waiting for their screening session. Non-participants were surveyed by postal questionnaire. Results: The sample...... was overall found to be sensitive to scope, testing at the conventional sample-mean level. At the individual respondent level, however, more than half of the respondents failed the tests. Potential determinants for failing the tests were examined in alternative regression models but few consistent...

  3. Contingent Weighting in Judgment and Choice.

    Science.gov (United States)

    1987-06-08

    Review, 94, 236-254. Grether, D. M., & Plott, C. R. (1979). Economic theory of choice and the preference rever- sal phenomenon. American Economic Review , 69...805-824. Loomes, G., & Sugden, R. (1983). A rationale for preference reversal. American Economic Review , 73, 428-432. Payne, J. W. (1982). Contingent...Lichtenstein, S. (1983). Preference reversals: A broader perspective. American Economic Review , 73, 596-605. Slovic, P., Lichtenstein, S

  4. Fuzzy Logic Based Power System Contingency Ranking

    Directory of Open Access Journals (Sweden)

    A. Y. Abdelaziz

    2013-02-01

    Full Text Available Voltage stability is a major concern in planning and operations of power systems. It is well known that voltage instability and collapse have led to major system failures. Modern transmission networks are more heavily loaded than ever before to meet the growing demand. One of the major consequences resulted from such a stressed system is voltage collapse or instability. This paper presents maximum loadability identification of a load bus in a power transmission network. In this study, Fast Voltage Stability Index (FVSI is utilized as the indicator of the maximum loadability termed as Qmax. In this technique, reactive power loading will be increased gradually at particular load bus until the FVSI reaches close to unity. Therefore, a critical value of FVSI was set as the maximum loadability point. This value ensures the system from entering voltage-collapse region. The main purpose in the maximum loadability assessment is to plan for the maximum allowable load value to avoid voltage collapse; which is important in power system planning risk assessment.The most important task in security analysis is the problem of identifying the critical contingencies from a large list of credible contingencies and ranks them according to their severity. The condition of voltage stability in a power system can be characterized by the use of voltage stability indices. This paper presents fuzzy approach for ranking the contingencies using composite-index based on parallel operated fuzzy inference engine. The Line Flow index (L.F and bus Voltage Magnitude (VM of the load buses are expressed in fuzzy set notation. Further, they are evaluated using Fuzzy rules to obtain overall Criticality Index. Contingencies are ranked based on decreasing order of Criticality Index and then provides the comparison of ranking obtained with FVSI method.

  5. Income contingent loans in higher education financing

    OpenAIRE

    Chapman, Bruce

    2016-01-01

    Around nine countries currently use a national income contingent loan (ICL) scheme for higher education tuition using the income tax system. Increased international interest in ICL validates an examination of its costs and benefits relative to the traditional financing system, government-guaranteed bank loans (GGBLs). Bank-type loans exhibit poor economic characteristics: namely, repayment hardships for the disadvantaged, and default. This damages credit reputations and can be associated with...

  6. Effects of anticipatory anxiety and visual input on postural sway in an aversive situation.

    Science.gov (United States)

    Ishida, Mitsuo; Saitoh, Junko; Wada, Maki; Nagai, Masanori

    2010-04-19

    We have previously reported that state anxiety scores were positively correlated with postural sway while standing upright and gazing at a visual target (Ohno et al., 2004 [16]). The present study examines the effect of anticipatory anxiety and visual input on postural control in healthy individuals. An unpredictable aversive sound (100dB SPL) was delivered in order to induce anticipatory anxiety. Participants were asked to stand upright on a force plate with their eyes open and closed, and their center of pressure (COP) was measured. Analysis of the postural parameters revealed that the path lengths of the COP and the enveloped areas were greater in the anticipatory situation with the aversive sound than in the silent situation. Fast Fourier transform analysis showed that the frequency component related to vestibular inputs (0.1-1.0Hz) was increased during the anticipatory situation. The lower frequency (anticipatory anxiety in healthy participants amplified the sway regardless of whether the eyes were open or closed, and that the vestibular inputs greatly influenced the amplification of postural sway.

  7. Communications Contingency Plan: Planning for Crises and Controversy. Phase 1

    Science.gov (United States)

    Treise, Deborah; Bernstein, Arla G.; Yates, Brad

    1998-01-01

    Interviews were conducted with a variety of Marshall Space Flight Center personnel and local media representatives in Huntsville, Alabama, in order to identify the current perceptions of these individuals regarding communication effectiveness between MSFC and the media. The purposes of the Phase One report are to (1) assess the need for a contingency plan for communicating in situations of crisis and controversy; (2) identify goals and objectives for the planning process; and (3) provide recommendations for future planning activities to achieve the goals and objectives outlined in Phase One. It is strongly recommended that MSFC personnel who are involved in communications with the media participate in a facilitated, strategic communications planning process in order to develop Phase Two of the Communications Contingency Plan (CCP). Phase Two will address (1) the categorizing, ranking and prioritizing of crises and controversies; (2) the development of action steps and implementation strategies for the CCP; and (3) the development of a monitoring and evaluation process for ongoing plan effectiveness.

  8. The Role of Intuition and Reasoning in Driving Aversion to Risk and Ambiguity

    OpenAIRE

    Butler, Jeffrey V.; Guiso, Luigi; Jappelli, Tullio

    2011-01-01

    Using information on a large sample of retail investors and experimental data we find that risk aversion and risk ambiguity are correlated: individuals who dislike risk also dislike ambiguity. We show that what links these traits is the way people handle decisions. Intuitive thinkers are less averse to risk and less averse to ambiguity than individuals who base their decisions on effortful reasoning. We confirm this finding in a series of experiments. One interpretation of our results is that...

  9. On the hierarchical risk-averse control problems for diffusion processes

    OpenAIRE

    Befekadu, Getachew K.; Veremyev, Alexander; Pasiliao, Eduardo L.

    2016-01-01

    In this paper, we consider a risk-averse control problem for diffusion processes, in which there is a partition of the admissible control strategy into two decision-making groups (namely, the {\\it leader} and {\\it follower}) with different cost functionals and risk-averse satisfactions. Our approach, based on a hierarchical optimization framework, requires that a certain level of risk-averse satisfaction be achieved for the {\\it leader} as a priority over that of the {\\it follower's} risk-ave...

  10. On the dynamic consistency of hierarchical risk-averse decision problems

    OpenAIRE

    Befekadu, Getachew K.; Pasiliao, Eduardo L.

    2016-01-01

    In this paper, we consider a risk-averse decision problem for controlled-diffusion processes, with dynamic risk measures, in which there are two risk-averse decision makers (i.e., {\\it leader} and {\\it follower}) with different risk-averse related responsibilities and information. Moreover, we assume that there are two objectives that these decision makers are expected to achieve. That is, the first objective being of {\\it stochastic controllability} type that describes an acceptable risk-exp...

  11. Integration of Neurobiological and Computational Analyses of the Neural Network Essentials for Conditioned Taste Aversion

    Science.gov (United States)

    1991-04-29

    insular cortex lesions on the conditioned taste aversion, passive avoidance, and neophobia in the rat using the excitotoxin ibotenic acid. Behavioral...Psychology .1, 5-6, 1973. Fitzgerald, R. E. and Burton, M. J. Neophobia and conditioned taste aversion deficits in the rat produced by undercutting temporal...1967. Nachman, M. and Ashe, J. H. Effects of basolateral amygdala lesions on neophobia , learned taste aversions, and sodium appetite in rats. Journal of

  12. A study of the user's perception of economic value in nursing visits to primary care by the method of contingent valuation.

    Science.gov (United States)

    Martín-Fernández, Jesús; Pérez-Rivas, Francisco Javier; Gómez-Gascón, Tomás; del Cura-González, Isabel; Tello Bernabé, Eugenia; Rodríguez-Martínez, Gemma; Polentinos-Castro, Elena; Domínguez-Bidagor, Julia; Ariza-Cardiel, Gloria; Conde-López, Juan Francisco; Beamud-Lagos, Milagros; Aguado-Arroyo, Oscar; Sanz-Bayona, Teresa; Gil-Lacruz, Ana Isabel

    2011-10-03

    The identification of the attribution of economic value that users of a health system assign to a health service could be useful in planning these services. The method of contingent valuation can provide information about the user's perception of value in monetary terms, and therefore comparable between services of a very different nature. This study attempts to extract the economic value that the subject, user of primary care nursing services in a public health system, attributes to this service by the method of contingent valuation, based on the perspectives of Willingness to Pay (WTP) and Willingness to Accept [Compensation] (WTA). This is an economic study with a transversal design. The contingent valuation method will be used to estimate the user's willingness to pay (WTP) for the care received from the primary care nurse and the willingness to accept [compensation] (WTA), were this service eliminated. A survey that meets the requisites of the contingent valuation method will be constructed and pilot-tested. Subsequently, 600 interviews will be performed with subjects chosen by systematic randomized sampling from among those who visit nursing at twenty health centers with different socioeconomic characteristics in the Community of Madrid. The characteristics of the subject and of the care received that can explain the variations in WTP, WTA and in the WTP/WTA ratio expressed will be studied. A theoretical validation of contingent valuation will be performed constructing two explanatory multivariate mixed models in which the dependent variable will be WTP, and the WTP/WTA relationship, respectively. The identification of the attribution of economic value to a health service that does not have a direct price at the time of use, such as a visit to primary care nursing, and the definition of a profile of "loss aversion" in reference to the service evaluated, can be relevant elements in planning, enabling incorporating patient preferences to health policy decision-making.

  13. A study of the user's perception of economic value in nursing visits to primary care by the method of contingent valuation

    Directory of Open Access Journals (Sweden)

    Conde-López Juan

    2011-10-01

    Full Text Available Abstract Background The identification of the attribution of economic value that users of a health system assign to a health service could be useful in planning these services. The method of contingent valuation can provide information about the user's perception of value in monetary terms, and therefore comparable between services of a very different nature. This study attempts to extract the economic value that the subject, user of primary care nursing services in a public health system, attributes to this service by the method of contingent valuation, based on the perspectives of Willingness to Pay (WTP and Willingness to Accept [Compensation] (WTA. Methods/Design This is an economic study with a transversal design. The contingent valuation method will be used to estimate the user's willingness to pay (WTP for the care received from the primary care nurse and the willingness to accept [compensation] (WTA, were this service eliminated. A survey that meets the requisites of the contingent valuation method will be constructed and pilot-tested. Subsequently, 600 interviews will be performed with subjects chosen by systematic randomized sampling from among those who visit nursing at twenty health centers with different socioeconomic characteristics in the Community of Madrid. The characteristics of the subject and of the care received that can explain the variations in WTP, WTA and in the WTP/WTA ratio expressed will be studied. A theoretical validation of contingent valuation will be performed constructing two explanatory multivariate mixed models in which the dependent variable will be WTP, and the WTP/WTA relationship, respectively. Discussion The identification of the attribution of economic value to a health service that does not have a direct price at the time of use, such as a visit to primary care nursing, and the definition of a profile of "loss aversion" in reference to the service evaluated, can be relevant elements in planning

  14. Dysphoric mood states are related to sensitivity to temporal changes in contingency

    Directory of Open Access Journals (Sweden)

    Rachel M. eMsetfi

    2012-09-01

    Full Text Available A controversial finding in the field of causal learning is that mood contributes to the accuracy of perceptions of uncorrelated relationships. When asked to report the degree of control between an action and its outcome, people with dysphoria or depression are claimed to be more realistic in reporting non-contingency (e.g., Alloy & Abramson, 1979. The strongest evidence for this depressive realism (DR effect is derived from data collected with experimental procedures in which the dependent variables are verbal or written ratings of contingency or cause, and, perhaps more importantly, the independent variable in these procedures may be ambiguous and difficult to define. In order to address these possible confounds, we used a two-response free-operant causal learning task in which the dependent measures were performance based. Participants were required to respond to maximise the occurrence of a temporally contiguous outcome that was programmed with different probabilities, which also varied temporally across two responses. Dysphoric participants were more sensitive to the changing outcome contingencies than controls even though they responded at a similar rate. During probe trials, in which the outcome was masked, their performance recovered more quickly than that of the control group. These data provide unexpected support for the depressive realism hypothesis suggesting that dysphoria is associated with heightened sensitivity to temporal shifts in contingency.

  15. Risk Aversion and Wealth: Evidence from Person-to-Person Lending Portfolios

    OpenAIRE

    Veronica Rappoport; Enrichetta Ravina; Daniel Paravisini

    2010-01-01

    We estimate risk aversion from the actual financial decisions of a sample of 2,168 U.S. investors participating in Lending Club, a person-to-person lending platform. We find a large degree of heterogeneity in the relative risk aversion (RRA) parameter, with an average of 2.85, and a median of 1.62. We exploit the panel dimension of the data to estimate independently the correlation between risk aversion and wealth in the cross section of investors, and the elasticity of risk aversion with res...

  16. Automated Contingency Management for Advanced Propulsion Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Impact Technologies LLC, in cooperation the Georgia Institute of Technology, proposes to develop and demonstrate an innovative Automated Contingency Management (ACM)...

  17. Motor contingency learning and infants with Spina Bifida.

    Science.gov (United States)

    Taylor, Heather B; Barnes, Marcia A; Landry, Susan H; Swank, Paul; Fletcher, Jack M; Huang, Furong

    2013-02-01

    Infants with Spina Bifida (SB) were compared to typically developing infants (TD) using a conjugate reinforcement paradigm at 6 months-of-age (n = 98) to evaluate learning, and retention of a sensory-motor contingency. Analyses evaluated infant arm-waving rates at baseline (wrist not tethered to mobile), during acquisition of the sensory-motor contingency (wrist tethered), and immediately after the acquisition phase and then after a delay (wrist not tethered), controlling for arm reaching ability, gestational age, and socioeconomic status. Although both groups responded to the contingency with increased arm-waving from baseline to acquisition, 15% to 29% fewer infants with SB than TD were found to learn the contingency depending on the criterion used to determine contingency learning. In addition, infants with SB who had learned the contingency had more difficulty retaining the contingency over time when sensory feedback was absent. The findings suggest that infants with SB do not learn motor contingencies as easily or at the same rate as TD infants, and are more likely to decrease motor responses when sensory feedback is absent. Results are discussed with reference to research on contingency learning in infants with and without neurodevelopmental disorders, and with reference to motor learning in school-age children with SB.

  18. Alleviating Contingency Violations through Visual Analytics and Suggested Actions

    Energy Technology Data Exchange (ETDEWEB)

    Rice, Mark J.; Huang, Zhenyu; Chen, Yousu; Allwardt, Craig H.; Mackey, Patrick S.

    2013-07-21

    Contingency analysis (CA) is essential in maintaining a stable and secure power grid. It is required by operating standards that contingency violations need to be alleviated within 30 minutes. In today’s practice, operators normally make decisions based on the information they have with limited support. This paper presents a new feature of user suggested actions integrated in the graphical contingency analysis (GCA) tool, developed by the authors to help the operator’s decision making process. This paper provides a few examples on showing how the decision support element of the GCA tool is further enhanced by this new feature to alleviate contingency violations for better grid reliability.

  19. Contingent methadone delivery: effects on illicit-opiate use.

    Science.gov (United States)

    Higgins, S T; Stitzer, M L; Bigelow, G E; Liebson, I A

    1986-07-01

    This study examined the effects of contingent vs. non-contingent delivery of a methadone dose supplement on relapse to illicit opiate use in the context of a methadone outpatient detoxification program. Following a 3-week methadone stabilization period on 30 mg, patients (N = 39) were randomly assigned to a contingent, a non-contingent, or a control treatment group. All patients received identical gradual reductions in their assigned methadone dose. During the dose reduction period (weeks 4-11), members of the contingent (N = 13) and non-contingent groups (N = 13) could obtain daily methadone-dose supplements up to 20 mg, but contingent group members could obtain supplements only if their most recent urinalysis results were opiate negative. Control subjects (N = 13) did not have dose increases available. The contingent group presented significantly lower opiate-positive urines during weeks 8-11 (14% positive) of the detox than the non-contingent (38% positive) or control (50% positive) groups. Additionally, the availability of extra methadone improved treatment retention and increased clinic attendance above levels observed in the control group. The potential for further use of methadone's reinforcing properties in the treatment of opiate dependence is discussed.

  20. Radiological Contingency Planning for the Mars Science Laboratory Launch

    Energy Technology Data Exchange (ETDEWEB)

    Paul Guss

    2008-03-01

    and assessment, sample collection and control, contaminated material release criteria, data management, reporting, recording, and even communications. The tools NSTec has available to support these efforts will be reported. The data platform NSTec will provide shall also be compatible with integration of assets and field data acquired with other DOE, NASA, state, and local resources, personnel, and equipment. This paper also outlines the organizational structure for response elements in radiological contingency planning.

  1. Dismissing Attachment Characteristics Dynamically Modulate Brain Networks Subserving Social Aversion

    Science.gov (United States)

    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

  2. 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.

  3. 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

  4. Contingency in the Cosmos and the Contingency of the Cosmos : Two Theological Approaches

    NARCIS (Netherlands)

    Drees, Wim

    2015-01-01

    Contingency in reality may be epistemic, due to incomplete knowledge or the intersection of unrelated causal trajectories. In quantum physics, it appears to be ontological. More fundamental and interesting is the limit-question ‘why is there something rather than nothing,’ pointing out the contingen

  5. Contingency in the Cosmos and the Contingency of the Cosmos : Two Theological Approaches

    NARCIS (Netherlands)

    Drees, W.B.

    2015-01-01

    Contingency in reality may be epistemic, due to incomplete knowledge or the intersection of unrelated causal trajectories. In quantum physics, it appears to be ontological. More fundamental and interesting is the limit-question ‘why is there something rather than nothing,’ pointing out the contingen

  6. Contingency Contractor Optimization Phase 3 Sustainment Database Design Document - Contingency Contractor Optimization Tool - Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Frazier, Christopher Rawls; Durfee, Justin David; Bandlow, Alisa; Gearhart, Jared Lee; Jones, Katherine A

    2016-05-01

    The Contingency Contractor Optimization Tool – Prototype (CCOT-P) database is used to store input and output data for the linear program model described in [1]. The database allows queries to retrieve this data and updating and inserting new input data.

  7. The Necessity of Contingency or Contingent Necessity: Meillassoux, Hegel, and the Subject

    Directory of Open Access Journals (Sweden)

    John Van Houdt

    2011-06-01

    Full Text Available This article addresses the relationship of contingency to necessity as developed by Quentin Meillassoux and G.W.F. Hegel. Meillassoux criticizes the restriction of possibility by modern philosophy to the conditions of the transcendental subject, which he calls ‘correlationism’, and opposes to this correlationism, mathematics as an absolute form of thought. The arch-figure of a metaphysical version of correlationism for Meillassoux is Hegel. This article argues that, while Meillassoux is right to criticize a version of correlationism for restricting the range of contingency, he overlooks Hegel’s unique contribution to this issue. Hegel provides us a version of necessity modeled on the mathematical proof which answers Meillassoux’s concerns about correlationist versions of necessity but does not altogether jettison the concept of the subject. Instead, the subject in Hegel is a contingent interruption which emerges from the breaks in the kinds of necessity we posit about the world. Hegel offers us a way of tying these two concepts together in what I call ‘contingent necessity’.

  8. Contingency in the Cosmos and the Contingency of the Cosmos : Two Theological Approaches

    NARCIS (Netherlands)

    Drees, W.B.

    Contingency in reality may be epistemic, due to incomplete knowledge or the intersection of unrelated causal trajectories. In quantum physics, it appears to be ontological. More fundamental and interesting is the limit-question ‘why is there something rather than nothing,’ pointing out the

  9. Resource Contingency Program : Draft Environmental Impact Statement.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1995-02-01

    In 1990, the Bonneville Power Administration (BPA) embarked upon the Resource Contingency Program (RCP) to fulfill its statutory responsibilities to supply electrical power to its utility, industrial and other customers in the Pacific Northwest. Instead of buying or building generating plants now, BPA has purchased options to acquire power later if needed. Three option development agreements were signed in September 1993 with three proposed natural gas-fired, combined cycle combustion turbine CT projects near Chehalis and Satsop Washington and near Hermiston, Oregon. This environmental impact statement addresses the environmental consequences of purchasing power from these options. This environmental impact statement addresses the environmental consequences of purchasing power from these options.

  10. Sustainability between Necessity, Contingency and Impossibility

    Directory of Open Access Journals (Sweden)

    Karl Bruckmeier

    2009-12-01

    Full Text Available Sustainable use of natural resources seems necessary to maintain functions and services of eco- and social systems in the long run. Efforts in policy and science for sustainable development have shown the splintering of local, national and global strategies. Sustainability becomes contingent and insecure with the actors´ conflicting knowledge, interests and aims, and seems even impossible through the “rebound”-effect. To make short and long term requirements of sustainability coherent requires critical, comparative and theoretical analysis of the problems met. For this purpose important concepts and theories are discussed in this review of recent interdisciplinary literature about resource management.

  11. Future contingencies and photovoltaic system worth

    Energy Technology Data Exchange (ETDEWEB)

    Jones, G. J.; Thomas, M. G.; Bonk, G. J.

    1982-01-01

    The value of dispersed photovoltaic systems connected to the utility grid has been calculated using the General Electric Optimized Generation Planning program. The 1986 to 2001 time period was used for this study. Photovoltaic systems were dynamically integrated, up to 5% total capacity, into 9 NERC based regions under a range of future fuel and economic contingencies. Value was determined by the change in revenue requirements due to the photovoltaic additions. Displacement of high cost fuel was paramount to value, while capacity displacement was highly variable and dependent upon regional fuel mix.

  12. Mars Exploration Rovers Launch Contingency Efforts

    Science.gov (United States)

    McGrath, Brian E.; Frostbutter, David A.; Parthasarathy, Karungulam N.; Heyler, Gene A.; Chang, Yale

    2004-02-01

    On 10 June 2003 at 1:58 p.m. Eastern Daylight Time (EDT) and 7 July 2003 at 11:18 p.m. EDT, two separate spacecraft/rovers were successfully launched to Mars atop a Delta II 7925 and Delta II 7925H, respectively. Each spacecraft/rover carried eight Light Weight Radioisotope Heater Units (LWRHUs) for thermal conditioning of electronics during the cold Martian nights. As a part of the joint National Aeronautics and Space Administration/U. S. Department of Energy safety effort, a contingency plan was prepared to address the unlikely events of an accidental suborbital reentry or out-of-orbit reentry. The objective of the contingency plan was to develop and implement procedures to predict, within the first hour, the probable Earth Impact Footprints (EIFs) for the LWRHUs or other possible spacecraft debris after an accidental reentry. No ablation burn-through of the heat sources' aeroshells was expected, as a result of earlier testing. Any predictions would be used in subsequent notification and recovery efforts. The Johns Hopkins University Applied Physics Laboratory, as part of a multi-agency team, was responsible for prediction of the EIFs, and the time of reentry from a potential orbital decay. The tools used to predict the EIFs included a Three-Degree-of-Freedom (3DOF) trajectory simulation code, a Six-Degree-of-Freedom (6DOF) code, a database of aerodynamic coefficients for the LWRHUs and other spacecraft debris, secure links to obtain tracking data, and a high fidelity special perturbation orbit integrator code to predict time of spacecraft reentry from orbital decay. This paper will discuss the contingency plan and process, as well as highlight the improvements made to the analytical tools. Improvements to the 3DOF, aerodynamic database, and orbit integrator and inclusion of the 6DOF have significantly enhanced the prediction capabilities. In the days before launch, the trajectory simulation codes were exercised and predictions of hypothetical EIFs were produced

  13. Evidence of range bias in contingent valuation payment scales.

    Science.gov (United States)

    Whynes, David K; Wolstenholme, Jane L; Frew, Emma

    2004-02-01

    The payment scale format has been widely used in willingness-to-pay studies in health care. Concerns have been expressed that the format is, in theory, prone to range bias, although this proposition has not been tested directly. We report the findings of a contingent valuation questionnaire study of colorectal cancer screening, wherein different subjects were provided with payment scales of two different lengths. Whilst the long-scale instrument included scale values up to pound 1000, the short-scale version extended only to pound 100. After controlling for inter-sample differences in, for example, income, education and health behaviour, it emerged that the long-scale instrument produced a mean willingness to pay more than 30% higher than that resulting from the short-scale version. We believe our findings to be strongly supportive of the likelihood of range bias in payment-scale instruments, with important consequences for the estimation of both average valuation and consumer surplus.

  14. PROVISIONS, CONTINGENCIES AND CPC 25 REMARKS : THE PERCEPTIONS OF THE ACTORS INVOLVED

    OpenAIRE

    2013-01-01

    With the introduction of the International Financial Reporting Standards (IFRS) in Brazil, the Accounting Pronouncements Committee (CPC) issued a so called CPC 25 that addresses as from 2008, with mandatory reporting accounting information following the new procedures as of December 31, 2010, the rules for accounting for provisions, contingent assets and liabilities in Brazil, it was opened a new horizon for the accounting practice in our country and finally reached the expected convergence o...

  15. The measurement of contingent valuation for health economics.

    Science.gov (United States)

    Bayoumi, Ahmed M

    2004-01-01

    In health economics, contingent valuation is a method that elicits an individual's monetary valuations of health programmes or health states. This article reviews the theory and conduct of contingent valuation studies, with suggestions for improving the future measurement of contingent valuation for health economics applications. Contingent valuation questions can be targeted to any of the following groups: the general population, to value health insurance premiums for programmes; users of a health programme, to value the associated programme costs; or individuals with a disease, to evaluate health states. The questions can be framed to ask individuals how much they would pay to obtain positive changes in health status or avoid negative changes in health status ('willingness to pay'; WTP) or how much they would need to be paid to compensate for a decrease in health status or for foregoing an improvement in heath status ('willingness to accept'; WTA). In general WTP questions yield more accurate and precise valuations than WTA questions. Payment card techniques, with follow-up bidding using direct interviews with visual aids, are well suited for small contingent valuation studies. Several biases may be operative when assessing contingent valuation, including biases in the way participants are selected, the way in which the questions are posed, the way in which individuals interpret probabilities and value gains relative to losses, and the way in which missing or extreme responses are interpreted. An important aspect of all contingent valuation studies is an assessment of respondents' understanding of the evaluation method and the valuation task. Contingent valuation studies should measure the potential influence of biases, the validity of contingent valuation tests as measures of QOL, and the reliability and responsiveness of responses. Future research should address equity concerns associated with using contingent valuation and explore contingent valuation as a

  16. No Occasion for Pleasure: The Self-Worth Contingency of a Setback and Coping With Humor

    Directory of Open Access Journals (Sweden)

    Fay Caroline Mary Geisler

    2014-08-01

    Full Text Available Whether or not one uses humor to cope with a setback may depend on the idiosyncratic relation of the setback to feeling of self-worth. All people pursue the higher order goal of self-validation, but people differ in what domains of life their self-worth is contingent upon and to what extent. In this article based on an incongruity theory of humor we argue that the use of humor in coping with a highly self-worth-contingent setback may be impeded by two cognitive-motivational processes: goal-driven activation and goal shielding. From the outlined theory we derived the hypothesis that the more a domain is contingent upon self-worth, the less likely a person will be to use humor to deal with a setback in that domain. We tested this hypothesis in two studies employing two forms of self-report, i.e., ratings of reaction likelihood to setbacks described at an abstract domain level (Study 1, and ranking of reaction likelihood to concrete setbacks from different domains (Study 2. The hypothesis was affirmed in different domains of self-worth contingency controlling for the influence of habitual coping with humor, coping by disengagement, and global self-esteem.

  17. Attentional Modulation of Brain Responses to Primary Appetitive and Aversive Stimuli.

    Directory of Open Access Journals (Sweden)

    Brent A Field

    Full Text Available Studies of subjective well-being have conventionally relied upon self-report, which directs subjects' attention to their emotional experiences. This method presumes that attention itself does not influence emotional processes, which could bias sampling. We tested whether attention influences experienced utility (the moment-by-moment experience of pleasure by using functional magnetic resonance imaging (fMRI to measure the activity of brain systems thought to represent hedonic value while manipulating attentional load. Subjects received appetitive or aversive solutions orally while alternatively executing a low or high attentional load task. Brain regions associated with hedonic processing, including the ventral striatum, showed a response to both juice and quinine. This response decreased during the high-load task relative to the low-load task. Thus, attentional allocation may influence experienced utility by modulating (either directly or indirectly the activity of brain mechanisms thought to represent hedonic value.

  18. Attentional Modulation of Brain Responses to Primary Appetitive and Aversive Stimuli

    Science.gov (United States)

    Field, Brent A.; Buck, Cara L.; McClure, Samuel M.; Nystrom, Leigh E.; Kahneman, Daniel; Cohen, Jonathan D.

    2015-01-01

    Studies of subjective well-being have conventionally relied upon self-report, which directs subjects’ attention to their emotional experiences. This method presumes that attention itself does not influence emotional processes, which could bias sampling. We tested whether attention influences experienced utility (the moment-by-moment experience of pleasure) by using functional magnetic resonance imaging (fMRI) to measure the activity of brain systems thought to represent hedonic value while manipulating attentional load. Subjects received appetitive or aversive solutions orally while alternatively executing a low or high attentional load task. Brain regions associated with hedonic processing, including the ventral striatum, showed a response to both juice and quinine. This response decreased during the high-load task relative to the low-load task. Thus, attentional allocation may influence experienced utility by modulating (either directly or indirectly) the activity of brain mechanisms thought to represent hedonic value. PMID:26158468

  19. Attentional Modulation of Brain Responses to Primary Appetitive and Aversive Stimuli.

    Science.gov (United States)

    Field, Brent A; Buck, Cara L; McClure, Samuel M; Nystrom, Leigh E; Kahneman, Daniel; Cohen, Jonathan D

    2015-01-01

    Studies of subjective well-being have conventionally relied upon self-report, which directs subjects' attention to their emotional experiences. This method presumes that attention itself does not influence emotional processes, which could bias sampling. We tested whether attention influences experienced utility (the moment-by-moment experience of pleasure) by using functional magnetic resonance imaging (fMRI) to measure the activity of brain systems thought to represent hedonic value while manipulating attentional load. Subjects received appetitive or aversive solutions orally while alternatively executing a low or high attentional load task. Brain regions associated with hedonic processing, including the ventral striatum, showed a response to both juice and quinine. This response decreased during the high-load task relative to the low-load task. Thus, attentional allocation may influence experienced utility by modulating (either directly or indirectly) the activity of brain mechanisms thought to represent hedonic value.

  20. Mice infected with low-virulence strains of Toxoplasma gondii lose their innate aversion to cat urine, even after extensive parasite clearance.

    Directory of Open Access Journals (Sweden)

    Wendy Marie Ingram

    Full Text Available 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.

  1. INVESTIGATION OF CONTINGENCY PATTERNS OF TEACHERS’ SCAFFOLDING IN TEACHING AND LEARNING MATHEMATICS

    Directory of Open Access Journals (Sweden)

    Anwar Anwar

    2016-12-01

    Full Text Available The purpose of this study is to investigate the patterns of scaffolding contingency in teaching and learning mathematics carried out by three teachers. Contingency patterns are obtained by examining the transcription from video recording of conversation fragments between teachers and students during the provision of scaffolding. The contingency patterns are drawn in three strategies: diagnostic strategy, intervention strategy, and checking diagnosis. The result shows that the three teachers expressed different interaction contingencies in their scaffolding activities: contingent dominant, non-contingent dominant, and pseudo-contingent. It is also found that the learning interaction performed by experienced teachers tends to be contingent dominant compared to novice teachers. Keywords: Contingency, Contingent Dominant, Non-Contingent Dominant, Pseudo Contingent, Scaffolding DOI: http://dx.doi.org/10.22342/jme.8.1.3410.65-76

  2. The Asymptotic Standard Errors of Some Estimates of Uncertainty in the Two-Way Contingency Table

    Science.gov (United States)

    Brown, Morton B.

    1975-01-01

    Estimates of conditional uncertainty, contingent uncertainty, and normed modifications of contingent uncertainity have been proposed for the two-way contingency table. The asymptotic standard errors of the estimates are derived. (Author)

  3. Universals versus historical contingencies in lexical evolution.

    Science.gov (United States)

    Bochkarev, V; Solovyev, V; Wichmann, S

    2014-12-06

    The frequency with which we use different words changes all the time, and every so often, a new lexical item is invented or another one ceases to be used. Beyond a small sample of lexical items whose properties are well studied, little is known about the dynamics of lexical evolution. How do the lexical inventories of languages, viewed as entire systems, evolve? Is the rate of evolution of the lexicon contingent upon historical factors or is it driven by regularities, perhaps to do with universals of cognition and social interaction? We address these questions using the Google Books N-Gram Corpus as a source of data and relative entropy as a measure of changes in the frequency distributions of words. It turns out that there are both universals and historical contingencies at work. Across several languages, we observe similar rates of change, but only at timescales of at least around five decades. At shorter timescales, the rate of change is highly variable and differs between languages. Major societal transformations as well as catastrophic events such as wars lead to increased change in frequency distributions, whereas stability in society has a dampening effect on lexical evolution.

  4. 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.

  5. Development of a New Departure Aversion Standard for Light Aircraft

    Science.gov (United States)

    Borer, Nicholas K.

    2017-01-01

    The Federal Aviation Administration (FAA) and European Aviation Safety Agency (EASA) have recently established new light aircraft certification rules that introduce significant changes to the current regulations. The changes include moving from prescriptive design requirements to performance-based standards, transferring many of the acceptable means of compliance out of the rules and into consensus standards. In addition, the FAA/EASA rules change the performance requirements associated with some of the more salient safety issues regarding light aircraft. One significant change is the elimination of spin recovery demonstration. The new rules now call for enhanced stall warning and aircraft handling characteristics that demonstrate resistance to inadvertent departure from controlled flight. The means of compliance with these changes in a safe, cost-effective manner is a challenging problem. This paper discusses existing approaches to reducing the likelihood of departure from controlled flight and introduces a new approach, dubbed Departure Aversion, which allows applicants to tailor the amount of departure resistance, stall warning, and enhanced safety equipment to meet the new proposed rules. The Departure Aversion approach gives applicants the freedom to select the most cost-effective portfolio for their design, while meeting the safety intent of the new rules, by ensuring that any combination of the selected approaches will be at a higher equivalent level of safety than today's status quo.

  6. Behaviour of dairy cows subjected to an aversive veterinary procedure.

    Directory of Open Access Journals (Sweden)

    Maria José Hötzel

    2009-03-01

    Full Text Available On small dairy farms that lack appropriate handling facilities, cows can be restrained and subjected to veterinary inspection or treatment in their milking environment, which in turn might influence the behaviour of the animals, disrupting routine management. A group of seven dairy cows kept on an intensive rotational pasture system and machine milked twice a day by two familiar handlers were exposed to a thorough clinical examination for three consecutive days. Behavioural data before and after the procedure were analyzed by ANOVA. The behaviour of all the cows during the procedure indicated strong aversiveness. Treatment did not influence the flight distance (metres kept from the veterinarian or from a person unknown by the cows, assessed before and after the procedure (veterinarian: before = 1.2 ± 0.1; after 0.8 ± 0.2; unknown: 1.0 ± 0.2 after 1.2 ± 0.2; p=0.3, nor did it affect the number of agonistic interactions within the group observed before (7.1 ± 2 and after (11.5 ± 3 the procedure (p=0.3, or reactivity score (p=0.2. These results do not support the conclusion that the repeated application of unavoidable aversive veterinary procedures in the milking environment will influence the behaviour of cows during milking or their reactivity to humans.

  7. Latent inhibition of a conditioned taste aversion in fetal rats.

    Science.gov (United States)

    Mickley, G Andrew; Hoxha, Zana; DiSorbo, Anthony; Wilson, Gina N; Remus, Jennifer L; Biesan, Orion; Ketchesin, Kyle D; Ramos, Linnet; Luchsinger, Joseph R; Prodan, Suzanna; Rogers, Morgan; Wiles, Nathanael R; Hoxha, Nita

    2014-04-01

    The etiology of schizophrenia's cognitive symptoms may have its basis in prenatal alterations of glutamate N-methyl-D-aspartate (NMDA) receptor functioning. Therefore, the current study investigated the effects of ketamine (an NMDA receptor blocking drug) on both a conditioned taste aversion (CTA) and latent inhibition (LI; a model of attentional capacity) in rat fetuses. We first sought to determine if a CTA could be diminished by nonreinforced preexposure to a CS in fetal rats (i.e., LI). We injected E18 pregnant Sprague-Dawley rats with 100% allicin (garlic taste) or an equal volume of saline. Some of the pregnant dams also received ketamine (100 mg/kg, i.p.). One day later (E19), the dams received a second injection of the CS, followed by either lithium chloride (the US) or saline. Finally, on E21 pups received oral lavage with allicin and observations of ingestive orofacial motor responses were recorded. When allicin had been paired with LiCl in utero, E21 fetuses exhibited a conditioned suppression of orofacial movements, indicative of an aversion to this taste. Preexposure to the garlic taste on E18 produced a LI of this CTA. Ketamine significantly disrupted the formation of the CTA and had some impact on LI. However, the direct effect of ketamine on LI is less certain since the drug also blocked the original CTA.

  8. 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…

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

    Directory of Open Access Journals (Sweden)

    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.

  10. Age-dependent MDPV-induced taste aversions and thermoregulation in adolescent and adult rats.

    Science.gov (United States)

    Merluzzi, Andrew P; Hurwitz, Zachary E; Briscione, Maria A; Cobuzzi, Jennifer L; Wetzell, Bradley; Rice, Kenner C; Riley, Anthony L

    2014-07-01

    Adolescent rats are more sensitive to the rewarding and less sensitive to the aversive properties of various drugs of abuse than their adult counterparts. Given a nationwide increase in use of "bath salts," the present experiment employed the conditioned taste aversion procedure to assess the aversive effects of 3,4-methylenedioxypyrovalerone (MDPV; 0, 1.0, 1.8, or 3.2 mg/kg), a common constituent in "bath salts," in adult and adolescent rats. As similar drugs induce thermoregulatory changes in rats, temperature was recorded following MDPV administration to assess if thermoregulatory changes were related to taste aversion conditioning. Both age groups acquired taste aversions, although these aversions were weaker and developed at a slower rate in the adolescent subjects. Adolescents increased and adults decreased body temperature following MDPV administration with no correlation to aversions. The relative insensitivity of adolescents to the aversive effects of MDPV suggests that MDPV may confer an increased risk in this population. © 2013 Wiley Periodicals, Inc.

  11. Preexposure to Salty and Sour Taste Enhances Conditioned Taste Aversion to Novel Sucrose

    Science.gov (United States)

    Flores, Veronica L.; Moran, Anan; Bernstein, Max; Katz, Donald B.

    2016-01-01

    Conditioned taste aversion (CTA) is an intensively studied single-trial learning paradigm whereby animals are trained to avoid a taste that has been paired with malaise. Many factors influence the strength of aversion learning; prominently studied among these is taste novelty--the fact that preexposure to the taste conditioned stimulus (CS)…

  12. Deciding under doubt: a theory of risk aversion, time discounting preferences, and educational decision-making

    NARCIS (Netherlands)

    R. Breen; H.G. van de Werfhorst; M.M. Jaeger

    2014-01-01

    We develop a rational choice model of educational decision-making in which the utility of educational choices depends on students’ risk aversion and their time discounting preferences. We argue for the role of risk aversion and time discounting preferences in the choice of different tracks in second

  13. 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...

  14. The Use of Positive Reinforcement to Strengthen a Client's Commitment to Aversion Therapy.

    Science.gov (United States)

    Kurlychek, Robert T.

    1979-01-01

    Although aversive therapeutic approaches can be very effective in eliminating undesirable behavior, many clients do not commit themselves to participating in an activity which is subjectively very unpleasant. The addition of a positive reinforcement system whereby the client is rewarded for engaging in aversive therapy is proposed. (Author)

  15. Further Evidence for the Summation of Latent Inhibition and Overshadowing in Rats' Conditioned Taste Aversion

    Science.gov (United States)

    Nagaishi, Takatoshi; Nakajima, Sadahiko

    2008-01-01

    Repeated exposures to a target taste (X) attenuated subsequent development of rats' conditioned aversion to X (latent inhibition effect). Presentation of another taste (A) after X in conditioning (serial X-A compound conditioning) also attenuated conditioned X aversion compared with conditioning without A (overshadowing). Furthermore, the latent…

  16. 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…

  17. 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 sam

  18. 78 FR 64879 - Liquidity and Contingency Funding Plans

    Science.gov (United States)

    2013-10-30

    ... liquidity regulation should include the option of membership in a Federal Home Loan Bank (FHLB), and ten... ADMINISTRATION 12 CFR Part 741 RIN 3133-AD96 Liquidity and Contingency Funding Plans AGENCY: National Credit... liquidity and a list of contingent liquidity sources that can be employed under adverse circumstances....

  19. Contingent reinforcement of abstinence with individuals abusing cocaine and marijuana.

    OpenAIRE

    Budney, A J; Higgins, S T; Delaney, D D; Kent, L; Bickel, W K

    1991-01-01

    Two males diagnosed with cocaine dependence received a behavioral intervention comprised of contingency management and the community reinforcement approach. During the initial phase of treatment, reinforcement was delivered contingent on submitting cocaine-free urine specimens. The community reinforcement approach involved two behavior therapy sessions each week. Almost complete cocaine abstinence was achieved, but regular marijuana use continued. During a second phase, reinforcement magnitud...

  20. Infant Contingency/Extinction Performance after Observing Partial Reinforcement

    Science.gov (United States)

    Weir, Catherine; Toland, Cynthia; King, Rose Ann; Martin, Lisa Maas

    2005-01-01

    Social information gathering by infants 6 and 12 months old was examined as a foundation for later social learning that may be uniquely human. Infant performance on a contingency/extinction task was studied following a caregiver demonstration of the contingency on varied reinforcement schedules. Infants who observed caregivers receive any…

  1. Universalistic and Contingency Predictions of Employee Satisfaction and Conflict.

    Science.gov (United States)

    Dewar, Robert; Werbel, James

    1979-01-01

    Reviews contingency and universalistic theoretical rationales linking satisfaction and conflict to organic and mechanistic styles of structure and control. Results indicate that contingency variables are frequently as good as, or even better than, universalistic variables as predictors of satisfaction and conflict. (Author/IRT)

  2. Effects of Contingency Contracting on Decreasing Student Tardiness.

    Science.gov (United States)

    Din, Feng S.; Isack, Lori R.; Rietveld, Jill

    A contingency contract program was implemented in this study to determine the effects of contingency contracting on decreasing student tardiness in high school classrooms. The participants were 32 high school students. Of the 32 participants, 16 were randomly assigned to the experimental group and the other 16 to the control group. The…

  3. Baseline Response Levels Are a Nuisance in Infant Contingency Learning

    Science.gov (United States)

    Millar, W. S.; Weir, Catherine

    2015-01-01

    The impact of differences in level of baseline responding on contingency learning in the first year was examined by considering the response acquisition of infants classified into baseline response quartiles. Whereas the three lower baseline groups showed the predicted increment in responding to a contingency, the highest baseline responders did…

  4. A Study on Contingency Learning in Introductory Physics Concepts

    Science.gov (United States)

    Scaife, Thomas M.

    investigation of their behavior, students were asked what rule they used when answering questions. Although the self-reported rules might not be congruent with their behavior, training with specific examples might affect how students explicitly think about physics problems. In addition to exploring the effectiveness of various training examples, the results were also compared to a cognitive theory of causality: the contingency model. Physical concepts can often be expressed in terms of causal relations (e.g., a net force causes an object to accelerate), and a large body of work has found that people make many decisions that are consistent with causal reasoning. The contingency model, in particular, explains how certain statistical regularities in the co-occurrence of two events can be interpreted by individuals as causal relations, and was chosen primarily because it of its robust results and simple, parsimonious form. The empirical results demonstrate that different categories of training examples did affect student answers differently. Furthermore, these effects were mostly consistent with the predictions made by the contingency model. When rule use was explored, the self-reported rules were consistent with contingency model predictions, but indicated that examples alone were insufficient to teach complex functional relationships between physical dimensions, such as torque.

  5. Direct activation of the ventral striatum in anticipation of aversive stimuli.

    Science.gov (United States)

    Jensen, Jimmy; McIntosh, Anthony R; Crawley, Adrian P; Mikulis, David J; Remington, Gary; Kapur, Shitij

    2003-12-18

    The brain "reward" system, centered on the limbic ventral striatum, plays a critical role in the response to pleasure and pain. The ventral striatum is activated in animal and human studies during anticipation of appetitive/pleasurable events, but its role in aversive/painful events is less clear. Here we present data from three human fMRI studies based on aversive conditioning using unpleasant cutaneous electrical stimulation and show that the ventral striatum is reliably activated. This activation is observed during anticipation and is not a consequence of relief after the aversive event. Further, the ventral striatum is activated in anticipation regardless of whether there is an opportunity to avoid the aversive stimulus or not. Our data suggest that the ventral striatum, a crucial element of the brain "reward" system, is directly activated in anticipation of aversive stimuli.

  6. 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.

  7. The Impact of the Contingency of Robot Feedback for HRI

    DEFF Research Database (Denmark)

    Fischer, Kerstin; Lohan, Katrin Solveig; Saunders, Joe

    2013-01-01

    In this paper, we investigate the impact the contingency of robot feedback may have on the quality of verbal human-robot interaction. In order to assess not only what the effects are but also what they are caused by, we carried out experiments in which naïve participants instructed the humanoid...... robot iCub on a set of shapes and on a stacking task in two conditions, once with socially contingent, nonverbal feedback implemented in response to different gaze and looming behaviors of the human tutor, and once with non-contingent, saliency-based feedback. The results of the analysis of participants......’ linguistic behaviors in the two conditions show that contingency has an impact on the complexity and the pre-structuring of the task for the robot, i.e. on the participants’ tutoring behaviors. Contingency thus plays a considerable role for learning by demonstration....

  8. QV modal distance displacement - a criterion for contingency ranking

    Energy Technology Data Exchange (ETDEWEB)

    Rios, M.A.; Sanchez, J.L.; Zapata, C.J. [Universidad de Los Andes (Colombia). Dept. of Electrical Engineering], Emails: mrios@uniandes.edu.co, josesan@uniandes.edu.co, cjzapata@utp.edu.co

    2009-07-01

    This paper proposes a new methodology using concepts of fast decoupled load flow, modal analysis and ranking of contingencies, where the impact of each contingency is measured hourly taking into account the influence of each contingency over the mathematical model of the system, i.e. the Jacobian Matrix. This method computes the displacement of the reduced Jacobian Matrix eigenvalues used in voltage stability analysis, as a criterion of contingency ranking, considering the fact that the lowest eigenvalue in the normal operation condition is not the same lowest eigenvalue in N-1 contingency condition. It is made using all branches in the system and specific branches according to the IBPF index. The test system used is the IEEE 118 nodes. (author)

  9. The Impact of the Contingency of Robot Feedback for HRI

    DEFF Research Database (Denmark)

    Fischer, Kerstin; Lohan, Katrin Solveig; Saunders, Joe

    2013-01-01

    In this paper, we investigate the impact the contingency of robot feedback may have on the quality of verbal human-robot interaction. In order to assess not only what the effects are but also what they are caused by, we carried out experiments in which naïve participants instructed the humanoid...... robot iCub on a set of shapes and on a stacking task in two conditions, once with socially contingent, nonverbal feedback implemented in response to different gaze and looming behaviors of the human tutor, and once with non-contingent, saliency-based feedback. The results of the analysis of participants......’ linguistic behaviors in the two conditions show that contingency has an impact on the complexity and the pre-structuring of the task for the robot, i.e. on the participants’ tutoring behaviors. Contingency thus plays a considerable role for learning by demonstration....

  10. Pain and disgust: the facial signaling of two aversive bodily experiences.

    Directory of Open Access Journals (Sweden)

    Miriam Kunz

    Full Text Available The experience of pain and disgust share many similarities, given that both are aversive experiences resulting from bodily threat and leading to defensive reactions. The aim of the present study was to investigate whether facial expressions are distinct enough to encode the specific quality of pain and disgust or whether they just encode the similar negative valence and arousal level of both states. In sixty participants pain and disgust were induced by heat stimuli and pictures, respectively. Facial responses (Facial Action Coding System as well as subjective responses were assessed. Our main findings were that nearly the same single facial actions were elicited during pain and disgust experiences. However, these single facial actions were displayed with different strength and were differently combined depending on whether pain or disgust was experienced. Whereas pain was mostly encoded by contraction of the muscles surrounding the eyes (by itself or in combination with contraction of the eyebrows; disgust was mainly accompanied by contraction of the eyebrows and--in contrast to pain--by raising of the upper lip as well as the combination of upper lip raise and eyebrow contraction. Our data clearly suggests that facial expressions seem to be distinct enough to encode not only the general valence and arousal associated with these two bodily aversive experiences, namely pain and disgust, but also the specific origin of the threat to the body. This implies that the differential decoding of these two states by an observer is possible without additional verbal or contextual information, which is of special interest for clinical practice, given that raising awareness in observers about these distinct differences could help to improve the detection of pain in patients who are not able to provide a self-report of pain (e.g., patients with dementia.

  11. Pain and disgust: the facial signaling of two aversive bodily experiences.

    Science.gov (United States)

    Kunz, Miriam; Peter, Jessica; Huster, Sonja; Lautenbacher, Stefan

    2013-01-01

    The experience of pain and disgust share many similarities, given that both are aversive experiences resulting from bodily threat and leading to defensive reactions. The aim of the present study was to investigate whether facial expressions are distinct enough to encode the specific quality of pain and disgust or whether they just encode the similar negative valence and arousal level of both states. In sixty participants pain and disgust were induced by heat stimuli and pictures, respectively. Facial responses (Facial Action Coding System) as well as subjective responses were assessed. Our main findings were that nearly the same single facial actions were elicited during pain and disgust experiences. However, these single facial actions were displayed with different strength and were differently combined depending on whether pain or disgust was experienced. Whereas pain was mostly encoded by contraction of the muscles surrounding the eyes (by itself or in combination with contraction of the eyebrows); disgust was mainly accompanied by contraction of the eyebrows and--in contrast to pain--by raising of the upper lip as well as the combination of upper lip raise and eyebrow contraction. Our data clearly suggests that facial expressions seem to be distinct enough to encode not only the general valence and arousal associated with these two bodily aversive experiences, namely pain and disgust, but also the specific origin of the threat to the body. This implies that the differential decoding of these two states by an observer is possible without additional verbal or contextual information, which is of special interest for clinical practice, given that raising awareness in observers about these distinct differences could help to improve the detection of pain in patients who are not able to provide a self-report of pain (e.g., patients with dementia).

  12. Neural activation during processing of aversive faces predicts treatment outcome in alcoholism.

    Science.gov (United States)

    Charlet, Katrin; Schlagenhauf, Florian; Richter, Anne; Naundorf, Karina; Dornhof, Lina; Weinfurtner, Christopher E J; König, Friederike; Walaszek, Bernadeta; Schubert, Florian; Müller, Christian A; Gutwinski, Stefan; Seissinger, Annette; Schmitz, Lioba; Walter, Henrik; Beck, Anne; Gallinat, Jürgen; Kiefer, Falk; Heinz, Andreas

    2014-05-01

    Neuropsychological studies reported decoding deficits of emotional facial expressions in alcohol-dependent patients, and imaging studies revealed reduced prefrontal and limbic activation during emotional face processing. However, it remains unclear whether this reduced neural activation is mediated by alcohol-associated volume reductions and whether it interacts with treatment outcome. We combined analyses of neural activation during an aversive face-cue-comparison task and local gray matter volumes (GM) using Biological Parametric Mapping in 33 detoxified alcohol-dependent patients and 33 matched healthy controls. Alcoholics displayed reduced activation toward aversive faces-neutral shapes in bilateral fusiform gyrus [FG; Brodmann areas (BA) 18/19], right middle frontal gyrus (BA46/47), right inferior parietal gyrus (BA7) and left cerebellum compared with controls, which were explained by GM differences (except for cerebellum). Enhanced functional activation in patients versus controls was found in left rostral anterior cingulate cortex (ACC) and medial frontal gyrus (BA10/11), even after GM reduction control. Increased ACC activation correlated significantly with less (previous) lifetime alcohol intake [Lifetime Drinking History (LDH)], longer abstinence and less subsequent binge drinking in patients. High LDH appear to impair treatment outcome via its neurotoxicity on ACC integrity. Thus, high activation of the rostral ACC elicited by affective faces appears to be a resilience factor predicting better treatment outcome. Although no group differences were found, increased FG activation correlated with patients' higher LDH. Because high LDH correlated with worse task performance for facial stimuli in patients, elevated activation in the fusiform 'face' area may reflect inefficient compensatory activation. Therapeutic interventions (e.g. emotion evaluation training) may enable patients to cope with social stress and to decrease relapses after detoxification.

  13. Prospect theory and body mass: Characterizing psychological parameters for weight-related risk attitudes and weight-gain aversion

    OpenAIRE

    2015-01-01

    We developed a novel decision-making paradigm that allows us to apply prospect theory in behavioral economics to body mass. 67 healthy young adults completed self-report measures and two decision-making tasks for weight-loss, as well as for monetary rewards. We estimated risk-related preference and loss aversion parameters for each individual, separately for weight-loss and monetary rewards choice data. Risk-seeking tendency for weight-loss was positively correlated with body mass index in in...

  14. Contingency Contractor Optimization Phase 3 Sustainment Requirements Document Contingency Contractor Optimization Tool - Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Bandlow, Alisa; Durfee, Justin David; Frazier, Christopher Rawls; Jones, Katherine A; Gearhart, Jared Lee

    2016-05-01

    This requirements document serves as an addendum to the Contingency Contractor Optimization Phase 2, Requirements Document [1] and Phase 3 Requirements Document [2]. The Phase 2 Requirements document focused on the high-level requirements for the tool. The Phase 3 Requirements document provided more detailed requirements to which the engineering prototype was built in Phase 3. This document will provide detailed requirements for features and enhancements being added to the production pilot in the Phase 3 Sustainment.

  15. Contingent stimuli signal subsequent reinforcer ratios.

    Science.gov (United States)

    Boutros, Nathalie; Davison, Michael; Elliffe, Douglas

    2011-07-01

    Conditioned reinforcer effects may be due to the stimulus' discriminative rather than its strengthening properties. While this was demonstrated in a frequently-changing choice procedure, a single attempt to replicate in a relatively static choice environment failed. We contend that this was because the information provided by the stimuli was nonredundant in the frequently-changing preparation, and redundant in the steady-state arrangement. In the present experiments, 6 pigeons worked in a steady-state concurrent schedule procedure with nonredundant informative stimuli (red keylight illuminations). When a response-contingent red keylight signaled that the next food delivery was more likely on one of the two alternatives, postkeylight choice responding was reliably for that alternative. This effect was enhanced after a history of extended informative red keylight presentation (Experiment 2). These results lend support to recent characterizations of conditioned reinforcer effects as reflective of a discriminative, rather than a reinforcing, property of the stimulus.

  16. Reinforcement of vocalizations through contingent vocal imitation.

    Science.gov (United States)

    Pelaez, Martha; Virues-Ortega, Javier; Gewirtz, Jacob L

    2011-01-01

    Maternal vocal imitation of infant vocalizations is highly prevalent during face-to-face interactions of infants and their caregivers. Although maternal vocal imitation has been associated with later verbal development, its potentially reinforcing effect on infant vocalizations has not been explored experimentally. This study examined the reinforcing effect of maternal vocal imitation of infant vocalizations using a reversal probe BAB design. Eleven 3- to 8-month-old infants at high risk for developmental delays experienced contingent maternal vocal imitation during reinforcement conditions. Differential reinforcement of other behavior served as the control condition. The behavior of 10 infants showed evidence of a reinforcement effect. Results indicated that vocal imitations can serve to reinforce early infant vocalizations.

  17. Appraising the use of contingent valuation.

    Science.gov (United States)

    Morrison, G C; Gyldmark, M

    1992-12-01

    The valuation of treatments and health states has been pursued in a number of ways. Most predominant are contingent valuation (CV), QALYs, and HYEs. CV--that is, willingness to pay and willingness to accept--is the only one of these methods that can be consistent with welfare economic theory, but, as discussed by Gafni (1990), in order to do so three criteria must be met. This article argues that the fulfilment of these criteria is not sufficient to obtain useful results, and some additional criteria are suggested. Several CV studies carried out in the area of health are reviewed, and their compliance or non-compliance, with both sets of criteria, is discussed. Finally, it is argued that, although CV is the more theoretically correct method, it is not a superior tool to QALYs and HYEs, and that the decision as to which is the appropriate valuation method depends on the policy issue at hand.

  18. Hippocampal unit activity during classical aversive and appetitive conditioning.

    Science.gov (United States)

    Segal, M; Disterhoft, J F; Olds, J

    1972-02-18

    Rats were trained with a tone being followed by either food or electric shock, on alternate days. Unit activity during application of the conditioned stimulus was recorded from the dorsal hippocampus. The results indicate differentiation of the hippocampal system. Dentate units respond by augmentation to a conditioned stimulus which leads to food and by inhibition to the same stimulus when it precedes electric shock. The hippocampus proper responds by augmentation in both situations. The intensity of the hippocampal response to the conditioned stimulus on the first day of training is higher if the unconditioned stimulus is food than if it is electric shock. These data cast light on the functions of the dorsal dentate-hippocampal connections and the hippocampus proper during aversive and appetitive conditioning.

  19. Supply Chain Coordination of Loss-Averse Newsvendor with Contract

    Institute of Scientific and Technical Information of China (English)

    ZHANG Long; SONG Shiji; WU Cheng

    2005-01-01

    This paper studies a supply chain model in which a single supplier sells a single product to a single retailer who faces the newsvendor problem. The retailer is loss averse. The results show that the optimal production quantity with decentralized decision making with a wholesale price contract is less than that with centralized decision making. The supply chain can achieve channel coordination with buy back and target rebate contracts. With buy back contracts, the supply chain system profits can be allocated arbitrarily between the supplier and retailer. A new kind of contract, the incremental buy back contract, gives similar results as with the buy back contract. The advantages and drawbacks of these three types of contracts are analyzed with numerical examples.

  20. Executive control suppresses pupillary responses to aversive stimuli.

    Science.gov (United States)

    Cohen, Noga; Moyal, Natali; Henik, Avishai

    2015-12-01

    Adaptive behavior depends on the ability to effectively regulate emotional responses. Continuous failure in the regulation of emotions can lead to heightened physiological reactions and to various psychopathologies. Recently, several behavioral and neuroimaging studies showed that exertion of executive control modulates emotion. Executive control is a high-order operation involved in goal-directed behavior, especially in the face of distractors or temptations. However, the role of executive control in regulating emotion-related physiological reactions is unknown. Here we show that exercise of executive control modulates reactivity of both the sympathetic and the parasympathetic components of the autonomic nervous system. Specifically, we demonstrate that both pupillary light reflex and pupil dilation for aversive stimuli are attenuated following recruitment of executive control. These findings offer new insights into the very basic mechanisms of emotion processing and regulation, and can lead to novel interventions for people suffering from emotion dysregulation psychopathologies. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Biophysics of risk aversion based on neurotransmitter receptor theory

    CERN Document Server

    Takahashi, Taiki

    2011-01-01

    Decision under risk and uncertainty has been attracting attention in neuroeconomics and neuroendocrinology of decision-making. This paper demonstrated that the neurotransmitter receptor theory-based value (utility) function can account for human and animal risk-taking behavior. The theory predicts that (i) when dopaminergic neuronal response is efficiently coupled to the formation of ligand-receptor complex, subjects are risk-aversive (irrespective of their satisfaction level) and (ii) when the coupling is inefficient, subjects are risk-seeking at low satisfaction levels, consistent with risk-sensitive foraging theory in ecology. It is further suggested that some anomalies in decision under risk are due to inefficiency of the coupling between dopamine receptor activation and neuronal response. Future directions in the application of the model to studies in neuroeconomics of addiction and neuroendocrine modulation of risk-taking behavior are discussed.

  2. Dopamine in motivational control: rewarding, aversive, and alerting.

    Science.gov (United States)

    Bromberg-Martin, Ethan S; Matsumoto, Masayuki; Hikosaka, Okihide

    2010-12-09

    Midbrain dopamine neurons are well known for their strong responses to rewards and their critical role in positive motivation. It has become increasingly clear, however, that dopamine neurons also transmit signals related to salient but nonrewarding experiences such as aversive and alerting events. Here we review recent advances in understanding the reward and nonreward functions of dopamine. Based on this data, we propose that dopamine neurons come in multiple types that are connected with distinct brain networks and have distinct roles in motivational control. Some dopamine neurons encode motivational value, supporting brain networks for seeking, evaluation, and value learning. Others encode motivational salience, supporting brain networks for orienting, cognition, and general motivation. Both types of dopamine neurons are augmented by an alerting signal involved in rapid detection of potentially important sensory cues. We hypothesize that these dopaminergic pathways for value, salience, and alerting cooperate to support adaptive behavior.

  3. Risk aversion and agents' survivability in a financial market

    Institute of Scientific and Technical Information of China (English)

    Serge HAYWARD

    2009-01-01

    Considering the effect of economic agents' pref-erences on their actions, the relationships between conven-tional summary statistics and forecast profits are investi-gated. An analytical examination of loss function families demonstrates that investors' utility maximisation is deter-mined by their risk attitudes. In computational settings,stock traders' fitness is assessed in response to a slow step increase in the value of the risk aversion coefficient. The ex-periment rejects the claims that the accuracy of the forecast does not depend upon which error-criteria are used and that none of them is related to the profitability of the forecast.The profitability of networks trained with L6 loss function appeared to be statistically significant and stable, although links between the loss functions and the accuracy of fore-casts were less conclusive.

  4. Gustatory insular cortex, aversive taste memory and taste neophobia.

    Science.gov (United States)

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

    2015-03-01

    Prior research indicates a role for the gustatory insular cortex (GC) in taste neophobia. Rats with lesions of the GC show much weaker avoidance to a novel and potentially dangerous taste than do neurologically intact animals. The current study used the retention of conditioned taste aversion (CTA) as a tool to determine whether the GC modulates neophobia by processing taste novelty or taste danger. The results show that GC lesions attenuate CTA retention (Experiment 1) and impair taste neophobia (Experiment 2). Given that normal CTA retention does not involve the processing of taste novelty, the pattern of results suggests that the GC is involved in taste neophobia via its function in processing the danger conveyed by a taste stimulus.

  5. Pharmacological modulation of aversive responsiveness in honey bees.

    Science.gov (United States)

    Tedjakumala, Stevanus R; Aimable, Margaux; Giurfa, Martin

    2013-01-01

    Within a honey bee colony, individuals performing different tasks exhibit different sensitivities to noxious stimuli. Noxious-stimulus sensitivity can be quantified in harnessed bees by measuring the sting extension response (SER) to a series of increasing voltages. Biogenic amines play a crucial role in the control of insect responsiveness. Whether or not these neurotransmitters affect the central control of aversive responsiveness, and more specifically of electric-shock responsiveness, remains unknown. Here we studied the involvement of the biogenic amines octopamine, dopamine and serotonin, and of the ecdysteroid 20-hydroxyecdisone in the central control of sting responsiveness to electric shocks. We injected pharmacological antagonists of these signaling pathways into the brain of harnessed bees and determined the effect of blocking these different forms of neurotransmission on shock responsiveness. We found that both octopamine and 20-hydroxyecdisone are dispensable for shock responsiveness while dopamine and serotonin act as down-regulators of sting responsiveness. As a consequence, antagonists of these two biogenic amines induce an increase in shock responsiveness to shocks of intermediate voltage; serotonin, can also increase non-specific responsiveness. We suggest that different classes of dopaminergic neurons exist in the bee brain and we define at least two categories: an instructive class mediating aversive labeling of conditioned stimuli in associative learning, and a global gain-control class which down-regulates responsiveness upon perception of noxious stimuli. Serotonergic signaling together with down-regulating dopaminergic signaling may play an essential role in attentional processes by suppressing responses to irrelevant, non-predictive stimuli, thereby allowing efficient behavioral performances.

  6. Predator-Resembling Aversive Conditioning for Managing Habituated Wildlife

    Directory of Open Access Journals (Sweden)

    Elsabé Louise Kloppers

    2005-06-01

    Full Text Available Wildlife habituation near urban centers can disrupt natural ecological processes, destroy habitat, and threaten public safety. Consequently, management of habituated animals is typically invasive and often includes translocation of these animals to remote areas and sometimes even their destruction. Techniques to prevent or reverse habituation and other forms of in situ management are necessary to balance ecological and social requirements, but they have received very little experimental attention to date. This study compared the efficacy of two aversive conditioning treatments that used either humans or dogs to create sequences resembling chases by predators, which, along with a control category, were repeatedly and individually applied to 24 moderately habituated, radio-collared elk in Banff National Park during the winter of 2001-2002. Three response variables were measured before and after treatment. Relative to untreated animals, the distance at which elk fled from approaching humans, i.e., the flight response distance, increased following both human and dog treatments, but there was no difference between the two treatments. The proportion of time spent in vigilance postures decreased for all treatment groups, without differences among groups, suggesting that this behavior responded mainly to seasonal effects. The average distance between elk locations and the town boundary, measured once daily by telemetry, significantly increased for human-conditioned elk. One of the co-variates we measured, wolf activity, exerted counteracting effects on conditioning effects; flight response distances and proximity to the town site were both lower when wolf activity was high. This research demonstrates that it is possible to temporarily modify aspects of the behavior of moderately habituated elk using aversive conditioning, suggests a method for reducing habituation in the first place, and provides a solution for Banff and other jurisdictions to manage

  7. Resurgence of instrumental behavior after an abstinence contingency.

    Science.gov (United States)

    Bouton, Mark E; Schepers, Scott T

    2014-06-01

    In resurgence, an extinguished instrumental behavior (R1) recovers when a behavior that has replaced it (R2) is also extinguished. The phenomenon may be relevant to understanding relapse that can occur after the termination of "contingency management" treatments, in which an unwanted behavior (e.g., substance abuse) is reduced by reinforcing an alternative behavior. When reinforcement is discontinued, the unwanted behavior might resurge. However, unlike most resurgence experiments, contingency management treatments also introduce a negative contingency, in which reinforcers are not delivered unless the client has abstained from the unwanted behavior. In two experiments with rats, we therefore examined the effects of adding a negative "abstinence" contingency to the resurgence design. During response elimination, R2 was not reinforced unless R1 had not been emitted for a minimum period of time (45, 90, or 135 s). In both experiments, adding such a contingency to simple R1 extinction reduced, but did not eliminate, resurgence. In Experiment 2, we found the same effect in a yoked group that could earn reinforcers for R2 at the same points in time as the negative-contingency group, but without the requirement to abstain from R1. Thus, the negative contingency per se did not contribute to the reduction in resurgence. These results suggest that the contingency reduced resurgence by making reinforcers more difficult to earn and more widely spaced in time. This could have allowed the animal to learn that R1 was extinguished in the "context" of infrequent reinforcement-a context more like that of resurgence testing. The results are thus consistent with a contextual (renewal) account of resurgence. The method might provide a better model of relapse after termination of a contingency management treatment.

  8. Assessing Energy Intake in Daily Life: Signal-Contingent Smartphone Application Versus Event-Contingent Paper and Pencil Estimated Diet Diary

    Directory of Open Access Journals (Sweden)

    Saskia Wouters

    2016-12-01

    Full Text Available Objectives: Investigating between-meal snack intake and its associated determinants such as emotions and stress presents challenges because both vary from moment to moment throughout the day. A smartphone application (app, was developed to map momentary between-meal snack intake and its associated determinants in the context of daily life. The aim of this study was to compare energy intake reported with the signal-contingent app and reported with an event-contingent paper and pencil diet diary. Methods: In a counterbalanced, cross-sectional design, adults (N = 46 from the general population reported between-meal snack intake during four consecutive days with the app and four consecutive days with a paper and pencil diet diary. A 10-day interval was applied between the two reporting periods. Multilevel regression analyses were conducted to compare both instruments on reported momentary and daily energy intake from snacks.  Results: Results showed no significant difference (B = 11.84, p = .14 in momentary energy intake from snacks between the two instruments. However, a significant difference (B = –105.89, p < .01 was found on energy intake from total daily snack consumption. Conclusions: As at momentary level both instruments were comparable in assessing energy intake, research purposes will largely determine the sampling procedure of choice. When momentary associations across time are the interest of study, a signal-contingent sampling procedure may be a suitable method. Since the compared instruments differed on two main features (i.e. the sampling procedure and the device used it is difficult to disentangle which instrument was the most accurate in assessing daily energy intake.

  9. 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.

  10. Activation of nucleus accumbens NMDA receptors differentially affects appetitive or aversive taste learning and memory

    Directory of Open Access Journals (Sweden)

    Luis eNuñez-Jaramillo

    2012-04-01

    Full Text Available Taste memory depends on motivational and post-ingestional consequences; thus, it can be aversive (e.g., conditioned taste aversion, CTA if a novel, palatable taste is paired with visceral malaise, or it can be appetitive if no intoxication appears after novel taste consumption, and a taste preference is developed. The nucleus accumbens (NAc plays a role in hedonic reactivity to taste stimuli, and recent findings suggest that reward and aversion are differentially encoded by the activity of NAc neurons. The present study examined whether the requirement for NMDA receptors in the NAc core during rewarding appetitive taste learning differs from that during aversive taste conditioning, as well as during retrieval of appetitive versus aversive taste memory, using the taste preference or CTA model, respectively. Bilateral infusions of NMDA (1 μg/μl, 0.5 μl into the NAc core were performed before acquisition or before retrieval of taste preference or CTA. Activation of NMDA receptors before taste preference training or CTA acquisition did not alter memory formation. Furthermore, NMDA injections before aversive taste retrieval had no effect on taste memory; however, 24 h later, CTA extinction was significantly delayed. Also, NMDA injections, made before familiar appetitive memory retrieval, interrupted the development of taste preference and produced a preference delay 24 h later. These results suggest that memory formation for a novel taste produces neurochemical changes in the NAc core that have differential requirements for NMDA receptors during retrieval of appetitive or aversive memory.

  11. The relationship between aversive conditioning and risk-avoidance in gambling.

    Science.gov (United States)

    Brunborg, Geir Scott; Johnsen, Bjørn Helge; Pallesen, Ståle; Molde, Helge; Mentzoni, Rune Aune; Myrseth, Helga

    2010-12-01

    This study investigated the relationship between aversive conditioning, heart rate variability suppression, behavioral activation system/behavioral inhibition system and risk-avoidance on the Iowa gambling task (IGT) in a nonclinical sample (29 male, 29 female, mean age = 20.7). A laboratory based Pavlovian aversive conditioning paradigm was used where a 1500 Hz tone (CS+) was followed by a burst of loud white noise (US), and a 850 Hz (CS-) tone was never followed by the US. In a subsequent extinction phase where the CS+ and CS- were presented without the US, conditioned skin conductance responses to the CS+ indicated aversive conditioning. The results showed that the participants who did not show aversive conditioning (N = 26) exhibited significantly less risk-avoidance compared to participants who did show aversive conditioning (N = 32). Regression analysis showed that among the study variables, only aversive conditioning contributed significantly to explaining variance in risk-avoidance. These results may have implications for understanding risk-taking in gambling in general, and may be a starting point understanding the role of aversive conditioning in the development and maintenance of gambling problems.

  12. Comparison of dependent measures used to quantify radiation-induced taste aversion

    Energy Technology Data Exchange (ETDEWEB)

    Spector, A.C.; Smith, J.C.; Hollander, G.R. (Florida State Univ., Tallahassee (USA). Dept. of Psychology)

    1981-11-01

    Several commonly used measures of conditioned taste aversion were compared under a variety of experimental conditions. In the first experiment an aversion to a saccharin solution (0.1%) was conditioned by pairing this taste substance with a single 100 R exposure to Cobalt-60. Comparisons were performed between the following measures: a short-term single-bottle test, a 22-hour two-bottle preference test, a measure quantifying recovery from the aversion along with other measures derived from these tests. Appropriate control groups received saccharin and sham exposure, water and sham exposure, and water and radiation exposure in order to measure both neophobia and enhanced neophobia. In Experiment 2 the total whole body radiation exposure used to condition the taste aversion was varied in different groups from 50 to 300 R exposures and the effect on conditioning was measured using the dependent variables described in Experiment 1. In Experiment 3 radiation-induced taste aversion was studied in rats which had prior exposures to the saccharin solution. In all three studies it was shown that different interpretations result from measuring the conditioned aversion with the different dependent variables commonly used, and several measures are needed to give a fair and accurate description of learned taste aversion.

  13. Application of the IPEBS method to dynamic contingency analysis

    Energy Technology Data Exchange (ETDEWEB)

    Martins, A.C.B. [FURNAS, Rio de Janeiro, RJ (Brazil); Pedroso, A.S. [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil)

    1994-12-31

    Dynamic contingency analysis is certainly a demanding task in the context of dynamic performance evaluation. This paper presents the results of a test for checking the contingency screening capability of the IPEBS method. A brazilian 1100-bus, 112-gen system was used in the test; the ranking of the contingencies based on critical clearing times obtained with IPEBS, was compared with the ranking derived from detailed time-domain simulation. The results of this comparison encourages us to recommended the use of the method in industry applications, in a complementary basis to the current method of time domain simulation. (author) 5 refs., 1 fig., 2 tabs.

  14. Serotonin modulates the effects of Pavlovian aversive predictions on response vigor.

    Science.gov (United States)

    Crockett, Molly J; Clark, Luke; Apergis-Schoute, Annemieke M; Morein-Zamir, Sharon; Robbins, Trevor W

    2012-09-01

    Updated theoretical accounts of the role of serotonin (5-HT) in motivation propose that 5-HT operates at the intersection of aversion and inhibition, promoting withdrawal in the face of aversive predictions. However, the specific cognitive mechanisms through which 5-HT modulates withdrawal behavior remain poorly understood. Behavioral inhibition in response to punishments reflects at least two concurrent processes: instrumental aversive predictions linking stimuli, responses, and punishments, and Pavlovian aversive predictions linking stimuli and punishments irrespective of response. In the current study, we examined to what extent 5-HT modulates the impact of instrumental vs Pavlovian aversive predictions on behavioral inhibition. We used acute tryptophan depletion to lower central 5-HT levels in healthy volunteers, and observed behavior in a novel task designed to measure the influence of Pavlovian and instrumental aversive predictions on choice (response bias) and response vigor (response latencies). After placebo treatment, participants were biased against responding on the button that led to punishment, and they were slower to respond in a punished context, relative to a non-punished context. Specifically, participants slowed their responses in the presence of stimuli predictive of punishments. Tryptophan depletion removed the bias against responding on the punished button, and abolished slowing in the presence of punished stimuli, irrespective of response. We suggest that this set of results can be explained by a role for 5-HT in Pavlovian aversive predictions. These findings suggest additional specificity for the influence of 5-HT on aversively motivated behavioral inhibition and extend recent models of the role of 5-HT in aversive predictions.

  15. Supply Chain Coordination with Sales Effort Effects and Impact of Loss Aversion on Effort Decision

    Institute of Scientific and Technical Information of China (English)

    SUO Hansheng; WANG Jingchun; JIN Yihui

    2005-01-01

    A new supply contract based on sharing the sales profits as well as the cost of effort was developed to coordinate the supply chain with sales effort effects. The contract coordinates the supplier's actions with voluntary compliance; the contract is symmetric in the sense that both the supplier's and retailer's profits are linearly correlated and is more easily implemented in some situations. The impact of the retailer's loss aversion on his effort is investigated based on the contract. After characterizing the retailer's optimal solutions, this paper demonstrates that contrary to intuition, loss aversion weakens incentives for retailer's sales effort and the retailer's optimal effort decreases as the loss aversion increases.

  16. 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.

  17. Comparing the executive attention of adult females with ADHD to that of females with sensory modulation disorder (SMD) under aversive and non-aversive auditory conditions.

    Science.gov (United States)

    Mazor-Karsenty, Tal; Parush, Shula; Bonneh, Yoram; Shalev, Lilach

    2015-02-01

    Certain behavioral expressions of sensory modulation disorder (SMD) such as distractibility, hyperactivity, and impulsivity are often similar to those of attention deficit/hyperactivity disorder (ADHD) in pediatric and adult populations. There is also a high comorbidity rate between these two diagnoses and absence of research regarding the objective neuropsychological differentiation between them. In the present study we employed a factorial design which enabled us to: (a) systematically examine the effects of SMD and ADHD on executive attention in a sample of adult females using a Stroop-like task, and (b) measure the effect of aversive conditions (sounds) on executive attention. The experimental measures used were the Stroop-like Location-Direction Task (SLDT) to assess executive attention and the battery of aversiveness to sounds (BAS), a standardized measure of aversive sounds that was developed for this study and enabled individual customization of aversive auditory sounds. Results revealed, as expected, a specific core deficit in executive attention for the ADHD factor. In addition to that, the present study provides an important, pioneering finding of SMD impairment in a unique combination of a cognitively demanding task with aversive sounds, providing preliminary objective evidence differentiating SMD from ADHD.

  18. 48 CFR 3.405 - Misrepresentations or violations of the Covenant Against Contingent Fees.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Misrepresentations or... INTEREST Contingent Fees 3.405 Misrepresentations or violations of the Covenant Against Contingent Fees. (a..., misrepresentation of a contingent fee arrangement, or other violation of the Covenant Against Contingent Fees shall...

  19. Effectiveness of Contrasting Approaches to Response-Contingent Learning among Children with Significant Developmental Delays and Disabilities

    Science.gov (United States)

    Raab, Melinda; Dunst, Carl J.; Hamby, Deborah W.

    2016-01-01

    Findings from a randomized controlled design study of an ability-based versus needs-based approach to response-contingent learning among children with significant developmental delays and disabilities who did not use instrumental behavior to produce reinforcing consequences are reported. The ability-based intervention and needs-based intervention…

  20. A Touch of Reinforcement: The Effects of Contingent Teacher Touch on the Classroom Behaviour of Young Children.

    Science.gov (United States)

    Wheldall, Kevin; And Others

    1986-01-01

    Two studies are reported in which the behaviors of four infant class teachers in England and their respective classes were observed and recorded. The aim of the studies was to examine the effects of contingent teacher touch behavior upon children's classroom behavior. Touch was found to increase on-task behavior and decrease disruptive behavior.…

  1. Contingent reinforcement of marijuana abstinence among individuals with serious mental illness: a feasibility study.

    Science.gov (United States)

    Sigmon, S C; Steingard, S; Badger, G J; Anthony, S L; Higgins, S T

    2000-11-01

    The feasibility of using monetary incentives to promote abstinence from marijuana use among individuals with serious mental illness was examined by using a within-subjects experimental design. Participants were 18 adults with schizophrenia or other serious mental illness who reported regular marijuana use. During 2 baseline conditions, participants received payment for submitting urine specimens independent of urinalysis results. During 3 incentive conditions, participants received varying amounts of money if urinalysis results were negative for recent marijuana use. The number of marijuana-negative specimens obtained was significantly greater during incentive than baseline conditions. These results provide evidence that marijuana use among at least some mentally ill individuals is sensitive to contingent reinforcement and support the potential feasibility of using contingency-management interventions to reduce substance abuse among the mentally ill.

  2. Self-Aware Aerospace Vehicle Contingency Management Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Aurora Flight Sciences, with Agent Oriented Software, proposes to develop a contingency management system that dynamically performs decision-making based on both...

  3. Chautauqua National Wildlife Refuge : Migratory Bird Disease Contingency Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Disease Contingency Plan for Chautauqua National Wildlife Refuge provides background information on migratory bird disease surveillance; an inventory of Refuge...

  4. Contingency Management and deliberative decision-making processes

    Directory of Open Access Journals (Sweden)

    Paul S. Regier

    2015-06-01

    Full Text Available Contingency Management is an effective treatment for drug addiction. The current explanation for its success is rooted in alternative reinforcement theory. We suggest that alternative reinforcement theory is inadequate to explain the success of Contingency Management and produce a model based on demand curves that show how little the monetary rewards offered in this treatment would affect drug use. Instead, we offer an explanation of its success based on the concept that it accesses deliberative decision-making processes. We suggest that Contingency Management is effective because it offers a concrete and immediate alternative to using drugs, which engages deliberative processes, improves the ability of those deliberative processes to attend to non-drug options, and offsets more automatic action-selection systems. This theory makes explicit predictions that can be tested, suggests which users will be most helped by Contingency Management, and suggests improvements in its implementation.

  5. Radial basis function networks for fast contingency ranking

    Energy Technology Data Exchange (ETDEWEB)

    Devaraj, D.; Ramar, K. [Indian Inst. of Technology, Madras (India). Dept. of Electrical Engineering; Yegnanarayana, B. [Indian Inst. of Technology, Madras (India). Dept. of Computer Science and Engineering

    2002-06-01

    This paper presents an artificial neural network-based approach for static-security assessment. The proposed approach uses radial basis function (RBF) networks to predict the system severity level following a given list of contingencies. The RBF networks are trained off-line to capture the nonlinear relationship between the pre-contingency line flows and the post-contingency severity index. A method based on mutual information is proposed for selecting the input features of the networks. Mutual information has the advantage of measuring the general relationship between the independent variables and the dependent variables as against the linear relationship measured by the correlation-based methods. The performance of the proposed approach is demonstrated through contingency ranking in IEEE 30-bus test system. (author)

  6. Migratory Bird Disease Contingency Plan: Union Slough NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Disease Contingency Plan for Union Slough National Wildlife Refuge provides background information on disease surveillance; an inventory of Refuge personnel,...

  7. Migratory Bird Disease Contingency Plan : Mingo National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Migratory Bird Disease Contingency Plan for Mingo NWR provides background information on disease surveillance; an inventory of Refuge personnel, equipment, and...

  8. Valuing Urban Forests: The Application of Contingent Valuation ...

    African Journals Online (AJOL)

    Choice-Academy

    1988-01-01

    Jan 1, 1988 ... Ethiopian Journal of Environmental Studies and Management Vol.1 No.2 June. ... Key words: contingent valuation, forest service functions, trees,. ... and water values, and recreational resources. ... human health conditions.

  9. Natural history's hypothetical moments: narratives of contingency in Victorian culture.

    Science.gov (United States)

    Choi, Tina Young

    2009-01-01

    This essay focuses on the ways in which works by Robert Chambers, Charles Darwin, and George Eliot encouraged readers to imagine the future as contingent. But where Chambers alludes to Charles Babbage's computational engine and the period's life insurance industry to hint at the role of contingency in natural history, Darwin insists on the importance of contingently determined outcomes to speciation. The "Origin" consistently exercises the reader's speculative energies by generating conditional statements, causal hypotheses, adn diverging alternatives. "Adam Bede" constitutes its characters' interior lives around the proliferation of such contingent narratives. To reflect on the future or on the past, these works suggest, demands a temporal, moral, and narrative complexity in one's thinking.

  10. Contingency Management and Deliberative Decision-Making Processes.

    Science.gov (United States)

    Regier, Paul S; Redish, A David

    2015-01-01

    Contingency management is an effective treatment for drug addiction. The current explanation for its success is rooted in alternative reinforcement theory. We suggest that alternative reinforcement theory is inadequate to explain the success of contingency management and produce a model based on demand curves that show how little the monetary rewards offered in this treatment would affect drug use. Instead, we offer an explanation of its success based on the concept that it accesses deliberative decision-making processes. We suggest that contingency management is effective because it offers a concrete and immediate alternative to using drugs, which engages deliberative processes, improves the ability of those deliberative processes to attend to non-drug options, and offsets more automatic action-selection systems. This theory makes explicit predictions that can be tested, suggests which users will be most helped by contingency management, and suggests improvements in its implementation.

  11. Automated Contingency Management for Advanced Propulsion Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Automated Contingency Management (ACM), or the ability to confidently and autonomously adapt to fault conditions with the goal of still achieving mission objectives,...

  12. Prospect theory and body mass: Characterizing psychological parameters for weight-related risk attitudes and weight-gain aversion

    Directory of Open Access Journals (Sweden)

    Seung-Lark eLim

    2015-03-01

    Full Text Available We developed a novel decision-making paradigm that allows us to apply prospect theory in behavioral economics to body mass. 67 healthy young adults completed self-report measures and two decision-making tasks for weight-loss, as well as for monetary rewards. We estimated risk-related preference and loss aversion parameters for each individual, separately for weight-loss and monetary rewards choice data. Risk-seeking tendency for weight-loss was positively correlated with body mass index in individuals who desired to lose body weight, whereas the risk-seeking for momentary rewards was not. Risk-seeking for weight-loss was correlated to excessive body shape preoccupations, while aversion to weight-gain was correlated with self-reports of behavioral involvement for successful weight-loss. We demonstrated that prospect theory can be useful in explaining the decision-making process related to body mass. Applying prospect theory is expected to advance our understanding of decision-making mechanisms in obesity, which might prove helpful for improving healthy choices.

  13. Prospect theory and body mass: characterizing psychological parameters for weight-related risk attitudes and weight-gain aversion.

    Science.gov (United States)

    Lim, Seung-Lark; Bruce, Amanda S

    2015-01-01

    We developed a novel decision-making paradigm that allows us to apply prospect theory in behavioral economics to body mass. 67 healthy young adults completed self-report measures and two decision-making tasks for weight-loss, as well as for monetary rewards. We estimated risk-related preference and loss aversion parameters for each individual, separately for weight-loss and monetary rewards choice data. Risk-seeking tendency for weight-loss was positively correlated with body mass index in individuals who desired to lose body weight, whereas the risk-seeking for momentary rewards was not. Risk-seeking for weight-loss was correlated to excessive body shape preoccupations, while aversion to weight-gain was correlated with self-reports of behavioral involvement for successful weight-loss. We demonstrated that prospect theory can be useful in explaining the decision-making process related to body mass. Applying prospect theory is expected to advance our understanding of decision-making mechanisms in obesity, which might prove helpful for improving healthy choices.

  14. Mini-Membrane Evaporator for Contingency Spacesuit Cooling

    Science.gov (United States)

    Makinen, Janice V.; Bue, Grant C.; Campbell, Colin; Petty, Brian; Craft, Jesse; Lynch, William; Wilkes, Robert; Vogel, Matthew

    2015-01-01

    The next-generation Advanced Extravehicular Mobility Unit (AEMU) Portable Life Support System (PLSS) is integrating a number of new technologies to improve reliability and functionality. One of these improvements is the development of the Auxiliary Cooling Loop (ACL) for contingency crewmember cooling. The ACL is a completely redundant, independent cooling system that consists of a small evaporative cooler--the Mini Membrane Evaporator (Mini-ME), independent pump, independent feedwater assembly and independent Liquid Cooling Garment (LCG). The Mini-ME utilizes the same hollow fiber technology featured in the full-sized AEMU PLSS cooling device, the Spacesuit Water Membrane Evaporator (SWME), but Mini-ME occupies only approximately 25% of the volume of SWME, thereby providing only the necessary crewmember cooling in a contingency situation. The ACL provides a number of benefits when compared with the current EMU PLSS contingency cooling technology, which relies upon a Secondary Oxygen Vessel; contingency crewmember cooling can be provided for a longer period of time, more contingency situations can be accounted for, no reliance on a Secondary Oxygen Vessel (SOV) for contingency cooling--thereby allowing a reduction in SOV size and pressure, and the ACL can be recharged-allowing the AEMU PLSS to be reused, even after a contingency event. The first iteration of Mini-ME was developed and tested in-house. Mini-ME is currently packaged in AEMU PLSS 2.0, where it is being tested in environments and situations that are representative of potential future Extravehicular Activities (EVA's). The second iteration of Mini-ME, known as Mini-ME2, is currently being developed to offer more heat rejection capability. The development of this contingency evaporative cooling system will contribute to a more robust and comprehensive AEMU PLSS.

  15. Relationship between maternal contingent responsiveness and infant social expectations

    OpenAIRE

    Mcquaid, Nancy Ella

    2007-01-01

    This study investigated the relationship between maternal contingent responsiveness and 4- and 5-month-old infants' (N = 61) social expectation behaviour in a Still Face procedure. Mothers were asked to interact with their infants for 2 minutes (Interactive phase), remain still-faced for 1 minute (Still Face phase), and resume interaction for 2 minutes. Mother and infant behaviour was assessed for the frequency of infant and mother smiles, mother smiles that were contingent to infant smiles d...

  16. Contingent Valuation: A Comparison of Referendum and Voluntary Contribution Mechanisms

    OpenAIRE

    Johnston, Marie

    2014-01-01

    Contingent valuation methods (CVM) are integral in valuating non-market environmental issues. Numerous mechanisms have been proposed and analysed, as well as numerous studies on willingness to pay (WTP) and willingness to accept (WTA) discrepancies. Despite the concentrated and persistent focus on achieving efficient mechanisms, controversies and limitations remain. This paper applies an open-ended approach to the referendum (majority voting) method for contingent valuation as advised by Gree...

  17. Contingency Management and Deliberative Decision-Making Processes

    OpenAIRE

    Regier, Paul S.; Redish, A. David

    2015-01-01

    Contingency management is an effective treatment for drug addiction. The current explanation for its success is rooted in alternative reinforcement theory. We suggest that alternative reinforcement theory is inadequate to explain the success of contingency management and produce a model based on demand curves that show how little the monetary rewards offered in this treatment would affect drug use. Instead, we offer an explanation of its success based on the concept that it accesses deliberat...

  18. Contingency Management and deliberative decision-making processes

    OpenAIRE

    Regier, Paul S.; David Redish, A.

    2015-01-01

    Contingency Management is an effective treatment for drug addiction. The current explanation for its success is rooted in alternative reinforcement theory. We suggest that alternative reinforcement theory is inadequate to explain the success of Contingency Management and produce a model based on demand curves that show how little the monetary rewards offered in this treatment would affect drug use. Instead, we offer an explanation of its success based on the concept that it accesses deliberat...

  19. Contingent liabilities or hidden liabilities? A review of disclosures

    Directory of Open Access Journals (Sweden)

    Stanisław Hońko

    2016-07-01

    Full Text Available This article aims to analyze information on contingent liabilities in the financial statements of selected listed companies. It forms part of the discussion on the principle of materiality, which recommends equivalence of the numerical part and notes to the financial statements. The study shows that the achievement of this equivalence is difficult, if at all possible. Contingent liabilities are not a popular research area. It is possible that this article may contribute to filling this gap.

  20. A dynamical systems account of sensorimotor contingencies

    Directory of Open Access Journals (Sweden)

    Thomas eBuhrmann

    2013-05-01

    Full Text Available According to the sensorimotor approach, perception is a form of embodied know-how, constituted by lawful regularities in the sensorimotor flow or in sensorimotor contingencies (SMCs in an active and situated agent. Despite the attention that this approach has attracted, there have been few attempts to define its core concepts formally. In this paper we examine the idea of SMCs and argue that its use involves notions that need to be distinguished. We introduce four distinct kinds of SMCs, which we define operationally. These are the notions of sensorimotor environment (open-loop motor-induced sensory variations, sensorimotor habitat (closed-loop sensorimotor trajectories, sensorimotor coordination (reliable sensorimotor patterns playing a functional role and sensorimotor strategy (normative organization of sensorimotor coordinations. We make use of a minimal dynamical model of visually-guided categorization to test the explanatory value of the different kinds of SMCs. Finally, we discuss the impact of our definitions on the conceptual development and empirical as well as model-based testing of the claims of the sensorimotor approach.

  1. Reaction-contingency based bipartite Boolean modelling

    Science.gov (United States)

    2013-01-01

    Background Intracellular signalling systems are highly complex, rendering mathematical modelling of large signalling networks infeasible or impractical. Boolean modelling provides one feasible approach to whole-network modelling, but at the cost of dequantification and decontextualisation of activation. That is, these models cannot distinguish between different downstream roles played by the same component activated in different contexts. Results Here, we address this with a bipartite Boolean modelling approach. Briefly, we use a state oriented approach with separate update rules based on reactions and contingencies. This approach retains contextual activation information and distinguishes distinct signals passing through a single component. Furthermore, we integrate this approach in the rxncon framework to support automatic model generation and iterative model definition and validation. We benchmark this method with the previously mapped MAP kinase network in yeast, showing that minor adjustments suffice to produce a functional network description. Conclusions Taken together, we (i) present a bipartite Boolean modelling approach that retains contextual activation information, (ii) provide software support for automatic model generation, visualisation and simulation, and (iii) demonstrate its use for iterative model generation and validation. PMID:23835289

  2. Contingency and construction: from mimesis to postmodernism

    Directory of Open Access Journals (Sweden)

    P. V. Zima

    1997-05-01

    Full Text Available In this article the transition from literary realism (Balzac, George Eliot, Verga is described as a shift from mimesis to constructivism. It is indicated how the realist confidence in the ability of the writer to represent reality as such yields to a modernist skepticism which recognises the contingent character of all fictional constructs. In spite of this discovery, modernists such as Kafka, Proust and Sartre still believe in a meaningful search for reality, authenticity and truth. This belief seems to disappear in the works of postmodernist authors such as Robbe-Grillet, Eco or Fowles who tend to dissociate fiction from any kind of meaningful search, transforming it into a game: a gadget for the reader. The author, who adopts the perspective of Critical Theory, argues towards the end of the article that the latter is modernist insofar as it refuses to follow the postmodernists in their playful abandoning of key realist and modernist concepts such as truth, authenticity and critique.

  3. Contingency Analysis of Cascading Line Outage Events

    Energy Technology Data Exchange (ETDEWEB)

    Thomas L Baldwin; Magdy S Tawfik; Miles McQueen

    2011-03-01

    As the US power systems continue to increase in size and complexity, including the growth of smart grids, larger blackouts due to cascading outages become more likely. Grid congestion is often associated with a cascading collapse leading to a major blackout. Such a collapse is characterized by a self-sustaining sequence of line outages followed by a topology breakup of the network. This paper addresses the implementation and testing of a process for N-k contingency analysis and sequential cascading outage simulation in order to identify potential cascading modes. A modeling approach described in this paper offers a unique capability to identify initiating events that may lead to cascading outages. It predicts the development of cascading events by identifying and visualizing potential cascading tiers. The proposed approach was implemented using a 328-bus simplified SERC power system network. The results of the study indicate that initiating events and possible cascading chains may be identified, ranked and visualized. This approach may be used to improve the reliability of a transmission grid and reduce its vulnerability to cascading outages.

  4. Was Thebes Necessary? Contingency in Spatial Modelling

    CERN Document Server

    Evans, Tim S

    2016-01-01

    When data is poor we resort to theory modelling. This is a two-step process. We have first to identify the appropriate type of model for the system under consideration and then to tailor it to the specifics of the case. To understand settlement formation, which is the concern of this paper, this not only involves choosing input parameter values such as site separations but also input functions which characterises the ease of travel between sites. Although the generic behaviour of the model is understood, the details are not. Different choices will necessarily lead to different outputs (for identical inputs). We can only proceed if choices that are "close" give outcomes are similar. Where there are local differences it suggests that there was no compelling reason for one outcome rather than the other. If these differences are important for the historic record we may interpret this as sensitivity to contingency. We re-examine the rise of Greek city states as first formulated by Rihll and Wilson in 1979, initial...

  5. Superior–subordinate dyads: Dependence of leader effectiveness on mutual reinforcement contingencies

    OpenAIRE

    Rao, Ram K.; Mawhinney, T. C.

    1991-01-01

    Task contingencies were modeled from bureaucratic organizations in which vague job descriptions provide incomplete contingency specifications. Response rates within dyads were examined using two nonsocial, two social, and two control contingencies. In the first social contingency, responses by the superior produced monetary reinforcement for a subordinate while the superior received no reinforcement from his subordinate. A second social contingency was identical to the first except that the s...

  6. Medial prefrontal cortex dopamine controls the persistent storage of aversive memories

    Directory of Open Access Journals (Sweden)

    María Carolina Gonzalez

    2014-11-01

    Full Text Available 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-tem aversive memories requires dopamine D1/D5 receptors activation in mPFC immediately after training and, depending on the task, between 6 and 12 hour 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.

  7. Dorsal hippocampal lesions impair blocking but not latent inhibition of taste aversion learning in rats.

    Science.gov (United States)

    Gallo, M; Cándido, A

    1995-06-01

    The aim of the present experiments was to study the effect of nonselective electrolytic lesions of the rat dorsal hippocampus on 2 learning phenomena: the L.J. Kamin (1969) blocking effect and latent inhibition of taste aversion learning. Bilateral dorsal hippocampal lesions selectively impaired blocking induced by 1 saccharin-lithium chloride pairing previous to 1 serial compound (saccharin-cider vinegar)-lithium pairing, but lesions had no effect on latent inhibition of a saline aversion, induced by 6 saline preexposures, in the same group of animals. Moreover, dorsal hippocampal lesions did not affect latent inhibition of saccharin-conditioned aversion induced by 1 or 6 preexposures. It is argued that blocking and latent inhibition of taste aversion learning do not share a common neural mechanism.

  8. 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

  9. Conditioned and Latent Inhibition in Taste-Aversion Learning: Clarifying the Role of Learned Safety

    Science.gov (United States)

    Best, Michael R.

    1975-01-01

    The following experiments are an attempt to clarify the role of learned safety by investigating the applicability of the concept of conditioned inhibition to a taste-aversion procedure and by differentiating its effects fromthose of latent inhibition. (Author)

  10. Effectiveness of lithium chloride induced taste aversions in reducing waterfowl nest predation

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Field experiments to evaluate the efficacy of lithium chloride (LiCI) as an aversive conditioning agent on waterfowl nest predators were conducted at Sand Lake...

  11. [Contingencies of self-worth in Japanese culture: validation of the Japanese contingencies of self-worth scale].

    Science.gov (United States)

    Uchida, Yukiko

    2008-08-01

    The author developed a Japanese version of the Contingencies of Self-Worth Scale (CSWS) that was originally developed in the United States (Crocker, Luhtanen, Cooper, & Bouvrette, 2003). The Japanese version of the scale measures seven contingencies of self-esteem: Defeating others in competition, appearance, relationship harmony, other's approval, academic competence, virtue, and support of family and friends. Scores on the scale had systematic relationships with related variables, and the scale therefore exhibited satisfactory levels of construct validity: Relationship harmony, other's approval, and support of family and friends were positively correlated with sympathy and interdependence, whereas competitiveness was negatively correlated with sympathy. Moreover, competitiveness and academic achievement contingencies predicted competitive motivation, whereas the support of family and friends contingency predicted self-sufficient motivation. The scale has adequate test-retest reliability and a seven-factor structural model was confirmed. The implications for self-esteem and interpersonal relationships in Japanese culture are discussed.

  12. 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....

  13. How do working-memory-related demand, reasoning ability and aversive reinforcement modulate conflict monitoring?

    Directory of Open Access Journals (Sweden)

    Anja eLeue

    2014-04-01

    Full Text Available Conflict monitoring is a process of stimulus evaluation and a pre-requisite for subsequent recruitment of cognitive control and behavioral adaptations. This study investigated how experimentally manipulated working-memory-related cognitive demand and aversive reinforcement modulate individual differences of conflict monitoring intensity and behavioral adjustments. Individual differences were assessed by means of an anxiety-related trait dimension (trait-BIS and by means of reasoning abilities–a core determinant of intelligence. Moreover, we investigated the special role of verbal reasoning ability and figural reasoning ability for the modulation of the conflict monitoring intensity. Ninety participants performed a go/nogo task with four conditions each comprising a combination of low vs. high working-memory-related cognitive demand and low vs. high aversive reinforcement. No effect of aversive reinforcement was observed for the N2 amplitude. The fronto-central nogo N2 amplitude was more pronounced for high demand vs. low demand suggesting that cognitive demand served as an aversive costly event. Higher total reasoning abilities were associated with more intense conflict monitoring and shorter response times with increasing aversive reinforcement (defined as verbal error-feedback vs. monetary loss. Individuals with higher trait-BIS scores demonstrated a more intense conflict monitoring even in conditions with low aversive reinforcement and also a more cautious responding (i.e., response times slowing with increasing aversive reinforcement indicating a focus on negative feedback prevention. The findings provide evidence for the conflict-monitoring theory and suggest that working-memory-related demand overrules the impact of aversive reinforcement on conflict monitoring intensity. Reasoning abilities and anxiety-related traits go along with an intensification of conflict monitoring but differences in the flexibility of behavioral adjustment.

  14. Medial prefrontal cortex dopamine controls the persistent storage of aversive memories

    OpenAIRE

    María Carolina Gonzalez; Cecilia Paula Kramar; Micol eTomaiuolo; Cynthia eKatche; Noelia eWeisstaub; Martín eCammarota; Jorge Horacio Medina

    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 imme...

  15. Naloxone fails to produce conditioned place aversion in mu-opioid receptor knock-out mice.

    Science.gov (United States)

    Skoubis, P D; Matthes, H W; Walwyn, W M; Kieffer, B L; Maidment, N T

    2001-01-01

    There is growing evidence that tonic activity of the opioid system may be important in the modulation of affective state. Naloxone produces a conditioned place aversion in rodents, an effect that is centrally mediated. Previous pharmacological data using antagonists with preferential actions at mu-, delta-, and kappa-opioid receptors indicate the importance of the mu-opioid receptor in mediating this effect. We sought to test the mu-opioid receptor selectivity of naloxone aversion using mu-opioid receptor knock-out mice. mu-Opioid receptor knock-out and wild-type mice were tested for naloxone (10 mg/kg, s.c.) aversion using a place conditioning paradigm. As a positive control for associative learning, knock-out mice were tested for conditioned place aversion to a kappa agonist, U50,488H (2 mg/kg, s.c.). Naloxone produced a significant place aversion in wild-type mice, but failed to have any effect in mu-opioid receptor knock-out mice. On the other hand, both knock-out and wild-type mice treated with U50,488H spent significantly less time in the drug-paired chamber compared to their respective vehicle controls. We conclude that the mu-opioid receptor is crucial for the acquisition of naloxone-induced conditioned place aversion. Furthermore, in a separate experiment using C57BL/6 mice, the delta-selective antagonist naltrindole (10 or 30 mg/kg, s.c.) failed to produce conditioned place aversion.Taken together, these data further support the notion that naloxone produces aversion by antagonizing tonic opioid activity at the mu-opioid receptor.

  16. Is Risk Aversion Really Correlated with Wealth? How estimated probabilities introduce spurious correlation

    OpenAIRE

    Lybbert, Travis J.; Just, David R

    2006-01-01

    Economists attribute many common behaviors to risk aversion and frequently focus on how wealth moderates risk preferences. This paper highlights a problem associated with empirical tests of the relationship between wealth and risk aversion that can arise when the probabilities individuals face are unobservable to researchers. The common remedy for unobservable probabilities involves the estimation of probabilities in a profit or production that includes farmer, farm and agro-climatic variable...

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

    Science.gov (United States)

    McCabe, Ciara; Rocha-Rego, Vanessa

    2016-01-01

    Background 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. Method 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. Results 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). Conclusions 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

  18. On the comparison of risk-neutral and risk-averse newsvendor problems

    OpenAIRE

    Abhilasha Prakash Katariya; Sila Cetinkaya; Eylem Tekin

    2014-01-01

    The objective of this paper is to investigate and compare the relationship between risk-neutral and risk-averse newsvendor problems under three different decision criteria: expected utility (EU) maximization, mean-variance (MV) analysis, and conditional value-at-risk (CVaR) minimization. Several models in the literature have shown that for special cases of the newsvendor problem (eg, no salvage value, no shortage penalty, and with recourse option), a risk-averse newsvendor orders less than a ...

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

    OpenAIRE

    Lijing Zhu; Ki-Sung Hong; Chulung Lee

    2013-01-01

    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...

  20. Effects of swim stress on latent inhibition using a conditioned taste aversion procedure.

    Science.gov (United States)

    Smith, Shawn; Fieser, Sarah; Jones, Jennifer; Schachtman, Todd R

    2008-10-20

    Rats were used to examine the effects of inescapable swim stress on latent inhibition using a conditioned taste aversion procedure. Subjects were subjected to inescapable swim after each of three saccharin taste preexposures and saccharin was later paired with LiCl. The ability of swim to influence latent inhibition was assessed on subsequent saccharin test trials. Swim stress significantly attenuated latent inhibition. The implications of these results regarding the effects of swim stress on conditioned taste aversion are discussed.

  1. 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.

  2. How do working-memory-related demand, reasoning ability and aversive reinforcement modulate conflict monitoring?

    Science.gov (United States)

    Leue, Anja; Weber, Bernd; Beauducel, André

    2014-01-01

    Conflict monitoring is a process of stimulus evaluation and a pre-requisite for subsequent recruitment of cognitive control and behavioral adaptations. This study investigated how experimentally manipulated working-memory-related cognitive demand and aversive reinforcement modulate individual differences of conflict monitoring intensity and behavioral adjustments. Individual differences were assessed by means of an anxiety-related trait dimension (trait-BIS) and by means of reasoning abilities-a core determinant of intelligence. Moreover, we investigated the special role of verbal reasoning ability and figural reasoning ability for the modulation of the conflict monitoring intensity. Ninety participants performed a go/nogo task with four conditions each comprising a combination of low vs. high working-memory-related cognitive demand and low vs. high aversive reinforcement. No effect of aversive reinforcement was observed for the N2 amplitude. The fronto-central nogo N2 amplitude was more pronounced for high demand vs. low demand suggesting that cognitive demand served as an aversive costly event. Higher total reasoning abilities were associated with more intense conflict monitoring and shorter response times with increasing aversive reinforcement (defined as verbal error-feedback vs. monetary loss). Individuals with higher trait-BIS scores demonstrated a more intense conflict monitoring even in conditions with low aversive reinforcement and also a more cautious responding (i.e., response times slowing) with increasing aversive reinforcement indicating a focus on negative feedback prevention. The findings provide evidence for the conflict monitoring theory and suggest that working-memory-related demand overrules the impact of aversive reinforcement on conflict monitoring intensity. Reasoning abilities and anxiety-related traits go along with an intensification of conflict monitoring but differences in the flexibility of behavioral adjustment.

  3. Newborn birth-weight of pregnant women on methadone or buprenorphine maintenance treatment: A national contingency management approach trial.

    Science.gov (United States)

    Peles, Einat; Sason, Anat; Schreiber, Shaul; Adelson, Miriam

    2017-03-01

    Methadone maintenance treatment (MMT) is the gold standard for pregnant women with opioid use disorders. Still, low birth-weights were reported, in particular of mothers who became pregnant before admission to MMT. We studied whether an escalating incentive contingency-management approach may contribute to better newborn birth-weights. A nationwide controlled randomized trial among all Israeli methadone/buprenorphine maintenance treatment (MBMT), newly or already in treatment pregnant women was performed. A modified contingency-management protocol with coupons of escalating value depending upon reduction of drug use, cigarette smoking, and alcohol consumption was compared to standard care arm. Drugs in urine, smoking (Fagerstrom score), alcohol use, and depression were monitored. Thirty-five women had 46 pregnancies. In their first pregnancy, 19 from the contingency-management and 16 from the standard care arms were studied. Contingency-management group as compared to the standard care arm included more newly admitted women (36.8% vs. 6.3%, p = .05), with benzodiazepine and cannabis onset at a younger age, and higher proportion of any drug abuse while pregnant (100% vs. 68.8%, p = .01). Fifteen of the contingency-management and 14 of the control arm gave birth (78.9% vs. 87.5%, p = .3) with similar proportions of normal (>2,500 g) birth-weight (71.4% vs. 61.5%, p = .8). Newborns' birth-weight was comparable among the two study arms indicating no contribution of the contingency-management approach. Small sample and baseline differences between arms might have influenced results. Intensive intervention should be evaluated on a larger scale of participants. (Am J Addict 2017;26:167-175). © 2017 American Academy of Addiction Psychiatry.

  4. Extremely sparse olfactory inputs are sufficient to mediate innate aversion in Drosophila.

    Directory of Open Access Journals (Sweden)

    Xiaojing J Gao

    Full Text Available Innate attraction and aversion to odorants are observed throughout the animal kingdom, but how olfactory circuits encode such valences is not well understood, despite extensive anatomical and functional knowledge. In Drosophila melanogaster, ~50 types of olfactory receptor neurons (ORNs each express a unique receptor gene, and relay information to a cognate type of projection neurons (PNs. To examine the extent to which the population activity of ORNs is required for olfactory behavior, we developed a genetic strategy to block all ORN outputs, and then to restore output in specific types. Unlike attraction, aversion was unaffected by simultaneous silencing of many ORNs, and even single ORN types previously shown to convey neutral valence sufficed to mediate aversion. Thus, aversion may rely on specific activity patterns in individual ORNs rather than the number or identity of activated ORNs. ORN activity is relayed into the brain by downstream circuits, with excitatory PNs (ePN representing a major output. We found that silencing the majority of ePNs did not affect aversion, even when ePNs directly downstream of single restored ORN types were silenced. Our data demonstrate the robustness of olfactory aversion, and suggest that its circuit mechanism is qualitatively different from attraction.

  5. Extremely sparse olfactory inputs are sufficient to mediate innate aversion in Drosophila.

    Science.gov (United States)

    Gao, Xiaojing J; Clandinin, Thomas R; Luo, Liqun

    2015-01-01

    Innate attraction and aversion to odorants are observed throughout the animal kingdom, but how olfactory circuits encode such valences is not well understood, despite extensive anatomical and functional knowledge. In Drosophila melanogaster, ~50 types of olfactory receptor neurons (ORNs) each express a unique receptor gene, and relay information to a cognate type of projection neurons (PNs). To examine the extent to which the population activity of ORNs is required for olfactory behavior, we developed a genetic strategy to block all ORN outputs, and then to restore output in specific types. Unlike attraction, aversion was unaffected by simultaneous silencing of many ORNs, and even single ORN types previously shown to convey neutral valence sufficed to mediate aversion. Thus, aversion may rely on specific activity patterns in individual ORNs rather than the number or identity of activated ORNs. ORN activity is relayed into the brain by downstream circuits, with excitatory PNs (ePN) representing a major output. We found that silencing the majority of ePNs did not affect aversion, even when ePNs directly downstream of single restored ORN types were silenced. Our data demonstrate the robustness of olfactory aversion, and suggest that its circuit mechanism is qualitatively different from attraction.

  6. Food aversion: a critical balance between allergen-specific IgE levels and taste preference.

    Science.gov (United States)

    Mirotti, Luciana; Mucida, Daniel; de Sá-Rocha, Luis Carlos; Costa-Pinto, Frederico Azevedo; Russo, Momtchilo

    2010-03-01

    Animals sensitized to allergens change their feeding behavior and avoid drinking the otherwise preferred sweetened solutions containing the allergens. This phenomenon, known as food aversion, appears to be mediated by allergen-specific IgE antibodies. Here we investigated food aversion in BALB/c and C57BL/6 mice, which differ in their allergic responses to the allergen ovalbumin as well as in their preference for sweet taste. BALB/c mice present higher levels of IgE and a natural lower preference for sweet flavors when compared to C57BL/6 mice. Specifically, we studied a conflicting situation in which animals simultaneously experienced the aversive contact with the allergen and the attractive sweet taste of increasing concentrations of sucrose. We found that BALB/c mice were more prone to develop food aversion than C57BL/6 mice and that this aversive behavior could be abolished in both strains by increasing the palatability of the solution containing the allergen. In both strains food aversion was positively correlated with the levels of allergen-specific IgE antibodies and inversely correlated with their preference for sucrose sweetened solutions. 2009 Elsevier Inc. All rights reserved.

  7. 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.

  8. Neurobiological mechanisms underlying the blocking effect in aversive learning.

    Science.gov (United States)

    Eippert, Falk; Gamer, Matthias; Büchel, Christian

    2012-09-19

    Current theories of classical conditioning assume that learning depends on the predictive relationship between events, not just on their temporal contiguity. Here we employ the classic experiment substantiating this reasoning-the blocking paradigm-in combination with functional magnetic resonance imaging (fMRI) to investigate whether human amygdala responses in aversive learning conform to these assumptions. In accordance with blocking, we demonstrate that significantly stronger behavioral and amygdala responses are evoked by conditioned stimuli that are predictive of the unconditioned stimulus than by conditioned stimuli that have received the same pairing with the unconditioned stimulus, yet have no predictive value. When studying the development of this effect, we not only observed that it was related to the strength of previous conditioned responses, but also that predictive compared with nonpredictive conditioned stimuli received more overt attention, as measured by fMRI-concurrent eye tracking, and that this went along with enhanced amygdala responses. We furthermore observed that prefrontal regions play a role in the development of the blocking effect: ventromedial prefrontal cortex (subgenual anterior cingulate) only exhibited responses when conditioned stimuli had to be established as nonpredictive for an outcome, whereas dorsolateral prefrontal cortex also showed responses when conditioned stimuli had to be established as predictive. Most importantly, dorsolateral prefrontal cortex connectivity to amygdala flexibly switched between positive and negative coupling, depending on the requirements posed by predictive relationships. Together, our findings highlight the role of predictive value in explaining amygdala responses and identify mechanisms that shape these responses in human fear conditioning.

  9. Muscarinic ACh Receptors Contribute to Aversive Olfactory Learning in Drosophila

    Directory of Open Access Journals (Sweden)

    Bryon Silva

    2015-01-01

    Full Text Available The most studied form of associative learning in Drosophila consists in pairing an odorant, the conditioned stimulus (CS, with an unconditioned stimulus (US. The timely arrival of the CS and US information to a specific Drosophila brain association region, the mushroom bodies (MB, can induce new olfactory memories. Thus, the MB is considered a coincidence detector. It has been shown that olfactory information is conveyed to the MB through cholinergic inputs that activate acetylcholine (ACh receptors, while the US is encoded by biogenic amine (BA systems. In recent years, we have advanced our understanding on the specific neural BA pathways and receptors involved in olfactory learning and memory. However, little information exists on the contribution of cholinergic receptors to this process. Here we evaluate for the first time the proposition that, as in mammals, muscarinic ACh receptors (mAChRs contribute to memory formation in Drosophila. Our results show that pharmacological and genetic blockade of mAChRs in MB disrupts olfactory aversive memory in larvae. This effect is not explained by an alteration in the ability of animals to respond to odorants or to execute motor programs. These results show that mAChRs in MB contribute to generating olfactory memories in Drosophila.

  10. Aversive Pavlovian Responses Affect Human Instrumental Motor Performance

    Science.gov (United States)

    Rigoli, Francesco; Pavone, Enea Francesco; Pezzulo, Giovanni

    2012-01-01

    In neuroscience and psychology, an influential perspective distinguishes between two kinds of behavioral control: instrumental (habitual and goal-directed) and Pavlovian. Understanding the instrumental-Pavlovian interaction is fundamental for the comprehension of decision-making. Animal studies (as those using the negative auto-maintenance paradigm), have demonstrated that Pavlovian mechanisms can have maladaptive effects on instrumental performance. However, evidence for a similar effect in humans is scarce. In addition, the mechanisms modulating the impact of Pavlovian responses on instrumental performance are largely unknown, both in human and non-human animals. The present paper describes a behavioral experiment investigating the effects of Pavlovian conditioned responses on performance in humans, focusing on the aversive domain. Results showed that Pavlovian responses influenced human performance, and, similar to animal studies, could have maladaptive effects. In particular, Pavlovian responses either impaired or increased performance depending on modulator variables such as threat distance, task controllability, punishment history, amount of training, and explicit punishment expectancy. Overall, these findings help elucidating the computational mechanisms underlying the instrumental-Pavlovian interaction, which might be at the base of apparently irrational phenomena in economics, social behavior, and psychopathology. PMID:23060738

  11. Acute stress affects risk taking but not ambiguity aversion.

    Science.gov (United States)

    Buckert, Magdalena; Schwieren, Christiane; Kudielka, Brigitte M; Fiebach, Christian J

    2014-01-01

    Economic decisions are often made in stressful situations (e.g., at the trading floor), but the effects of stress on economic decision making have not been systematically investigated so far. The present study examines how acute stress influences economic decision making under uncertainty (risk and ambiguity) using financially incentivized lotteries. We varied the domain of decision making as well as the expected value of the risky prospect. Importantly, no feedback was provided to investigate risk taking and ambiguity aversion independent from learning processes. In a sample of 75 healthy young participants, 55 of whom underwent a stress induction protocol (Trier Social Stress Test for Groups), we observed more risk seeking for gains. This effect was restricted to a subgroup of participants that showed a robust cortisol response to acute stress (n = 26). Gambling under ambiguity, in contrast to gambling under risk, was not influenced by the cortisol response to stress. These results show that acute psychosocial stress affects economic decision making under risk, independent of learning processes. Our results further point to the importance of cortisol as a mediator of this effect.

  12. Acute stress affects risk taking but not ambiguity aversion

    Directory of Open Access Journals (Sweden)

    Magdalena eBuckert

    2014-05-01

    Full Text Available Economic decisions are often made in stressful situations (e.g., at the trading floor, but the effects of stress on economic decision making have not been systematically investigated so far. The present study examines how acute stress influences economic decision making under uncertainty (risk and ambiguity using financially incentivized lotteries. We varied the domain of decision making as well as the expected value of the risky prospect. Importantly, no feedback was provided to investigate risk taking and ambiguity aversion independent from learning processes. In a sample of 75 healthy young participants, 55 of whom underwent a stress induction protocol (Trier Social Stress Test for Groups, we observed more risk seeking for gains. This effect was restricted to a subgroup of participants that showed a robust cortisol response to acute stress (n = 26. Gambling under ambiguity, in contrast to gambling under risk, was not influenced by the cortisol response to stress. These results show that acute psychosocial stress affects economic decision making under risk, independent of learning processes. Our results further point to the importance of cortisol as a mediator of this effect.

  13. Muscarinic ACh Receptors Contribute to Aversive Olfactory Learning in Drosophila

    Science.gov (United States)

    Silva, Bryon; Molina-Fernández, Claudia; Ugalde, María Beatriz; Tognarelli, Eduardo I.; Angel, Cristian; Campusano, Jorge M.

    2015-01-01

    The most studied form of associative learning in Drosophila consists in pairing an odorant, the conditioned stimulus (CS), with an unconditioned stimulus (US). The timely arrival of the CS and US information to a specific Drosophila brain association region, the mushroom bodies (MB), can induce new olfactory memories. Thus, the MB is considered a coincidence detector. It has been shown that olfactory information is conveyed to the MB through cholinergic inputs that activate acetylcholine (ACh) receptors, while the US is encoded by biogenic amine (BA) systems. In recent years, we have advanced our understanding on the specific neural BA pathways and receptors involved in olfactory learning and memory. However, little information exists on the contribution of cholinergic receptors to this process. Here we evaluate for the first time the proposition that, as in mammals, muscarinic ACh receptors (mAChRs) contribute to memory formation in Drosophila. Our results show that pharmacological and genetic blockade of mAChRs in MB disrupts olfactory aversive memory in larvae. This effect is not explained by an alteration in the ability of animals to respond to odorants or to execute motor programs. These results show that mAChRs in MB contribute to generating olfactory memories in Drosophila. PMID:26380118

  14. Effects of endocannabinoid and endovanilloid systems on aversive memory extinction.

    Science.gov (United States)

    Laricchiuta, Daniela; Centonze, Diego; Petrosini, Laura

    2013-11-01

    In contextual fear conditioning animals have to integrate various elemental stimuli into a coherent representation of the condition and then associate context representation with punishment. Although several studies indicated the modulating role of endocannabinoid system (ECS) on the associative learning, ECS effect on contextual fear conditioning requires further investigations. The present study assessed the effects of the increased endocannabinoid anandamide (AEA) tone on acquisition, retrieval and extinction of the contextual fear conditioning. Given that AEA may bind to cannabinoid type 1 (CB1) receptors as well as to postsynaptic ionotropic Transient Receptor Potential Vanilloid type 1 (TRPV1) channels, particular attention was paid in determining how the increased AEA tone influenced fear responses. Furthermore, it was investigated how the ECS modulated the effects of stress-sensitization on fear response. Thus, mice submitted or not to a social defeat stress protocol were treated with drugs acting on ECS, CB1 receptors or TRPV1 channels and tested in a contextual fear conditioning whose conditioning, retrieval and extinction phases were analyzed. ECS activation influenced the extinction process and contrasted the stress effects on fear memory. Furthermore, CB1 receptor antagonist blocked and TRPV1 channel antagonist promoted short- and long-term extinction. The present study indicates that ECS controls the extinction of aversive memories in the contextual fear conditioning.

  15. Does the kappa opioid receptor system contribute to pain aversion?

    Directory of Open Access Journals (Sweden)

    Catherine M Cahill

    2014-11-01

    Full Text Available The kappa opioid receptor (KOR and the endogenous peptide-ligand dynorphin have received significant attention due the involvement in mediating a variety of behavioral and neurophysiological responses, including opposing the rewarding properties of drugs of abuse including opioids. Accumulating evidence indicates this system is involved in regulating states of motivation and emotion. Acute activation of the KOR produces an increase in motivational behavior to escape a threat, however, KOR activation associated with chronic stress leads to the expression of symptoms indicative of mood disorders. It is well accepted that KOR can produce analgesia and is engaged in chronic pain states including neuropathic pain. Spinal studies have revealed KOR-induced analgesia in reversing pain hypersensitivities associated with peripheral nerve injury. While systemic administration of KOR agonists attenuates nociceptive sensory transmission, this effect appears to be a stress-induced effect as anxiolytic agents, including delta opioid receptor agonists, mitigate KOR agonist-induced analgesia. Additionally, while the role of KOR and dynorphin in driving the dysphoric and aversive components of stress and drug withdrawal has been well characterized, how this system mediates the negative emotional states associated with chronic pain is relatively unexplored. This review provides evidence that dynorphin and the KOR system contribute to the negative affective component of pain and that this receptor system likely contributes to the high comorbidity of mood disorders associated with chronic neuropathic pain.

  16. Acute stress affects risk taking but not ambiguity aversion

    Science.gov (United States)

    Buckert, Magdalena; Schwieren, Christiane; Kudielka, Brigitte M.; Fiebach, Christian J.

    2014-01-01

    Economic decisions are often made in stressful situations (e.g., at the trading floor), but the effects of stress on economic decision making have not been systematically investigated so far. The present study examines how acute stress influences economic decision making under uncertainty (risk and ambiguity) using financially incentivized lotteries. We varied the domain of decision making as well as the expected value of the risky prospect. Importantly, no feedback was provided to investigate risk taking and ambiguity aversion independent from learning processes. In a sample of 75 healthy young participants, 55 of whom underwent a stress induction protocol (Trier Social Stress Test for Groups), we observed more risk seeking for gains. This effect was restricted to a subgroup of participants that showed a robust cortisol response to acute stress (n = 26). Gambling under ambiguity, in contrast to gambling under risk, was not influenced by the cortisol response to stress. These results show that acute psychosocial stress affects economic decision making under risk, independent of learning processes. Our results further point to the importance of cortisol as a mediator of this effect. PMID:24834024

  17. Aversive Pavlovian responses affect human instrumental motor performance

    Directory of Open Access Journals (Sweden)

    Francesco eRigoli

    2012-10-01

    Full Text Available In neuroscience and psychology, an influential perspective distinguishes between two kinds of behavioural control: instrumental (habitual and goal-directed and Pavlovian. Understanding the instrumental-Pavlovian interaction is fundamental for the comprehension of decision-making. Animal studies (as those using the negative auto-maintenance paradigm, have demonstrated that Pavlovian mechanisms can have maladaptive effects on instrumental performance. However, evidence for a similar effect in humans is scarce. In addition, the mechanisms modulating the impact of Pavlovian responses on instrumental performance are largely unknown, both in human and non-human animals. The present paper describes a behavioural experiment investigating the effects of Pavlovian conditioned responses on performance in humans, focusing on the aversive domain. Results showed that Pavlovian responses influenced human performance, and, similar to animal studies, could have maladaptive effects. In particular, Pavlovian responses either impaired or increased performance depending on modulator variables such as threat distance, task controllability, punishment history, amount of training, and explicit punishment expectancy. Overall, these findings help elucidating the computational mechanisms underlying the instrumental-Pavlovian interaction, which might be at the base of apparently irrational phenomena in economics, social behaviour, and psychopathology.

  18. Relationship-contingent self-esteem and the ups and downs of romantic relationships.

    Science.gov (United States)

    Knee, C Raymond; Canevello, Amy; Bush, Amber L; Cook, Astrid

    2008-09-01

    Relationship-contingent self-esteem (RCSE) emerges from perspectives on authenticity, need fulfillment, and relationship functioning and is an unhealthy form of self-esteem that depends on one's relationship. Four studies provided evidence of convergent, discriminant, incremental, and predictive validity for RCSE. Study 1 tested associations between RCSE and several conceptually related and unrelated constructs in multiple samples. In Study 2, the authors employed an event-contingent diary procedure to examine reports of self-esteem as a function of everyday relationship events. The association between event valence and changes in self-esteem became stronger with RCSE, and this interaction remained controlling for several parallel interactions by other constructs. Study 3 employed an interval-contingent diary procedure and found support for a mediation model in which the moderating role of RCSE largely occurred through momentary emotions, which in turn predicted momentary self-esteem. Study 4 sampled couples and found that partners who were both higher in RCSE felt more committed but not more satisfied or close.

  19. Aversive startle potentiation and fear pathology: Mediating role of threat sensitivity and moderating impact of depression.

    Science.gov (United States)

    Yancey, James R; Vaidyanathan, Uma; Patrick, Christopher J

    2015-11-01

    Enhanced startle reactivity during exposure to unpleasant cues (aversive startle potentiation; ASP) appears in the RDoC matrix as a physiological index of acute threat response. Increased ASP has been linked to focal fear disorders and to scale measures of dispositional fearfulness (i.e., threat sensitivity; THT+). However, some studies have reported reduced ASP for fear pathology accompanied by major depressive disorder (MDD) or pervasive distress. The current study evaluated whether (a) THT+ as indexed by reported dispositional fearfulness mediates the relationship between fear disorders (when unaccompanied by depression) and ASP, and (b) depression moderates relations of THT+ and fear disorders with ASP. Fear disorder participants without MDD showed enhanced ASP whereas those with MDD (or other distress conditions) showed evidence of reduced ASP. Continuous THT+ scores also predicted ASP, and this association: (a) was likewise moderated by depression/distress, and (b) accounted for the relationship between ASP and fear pathology without MDD. These findings point to a role for the RDoC construct of acute threat, operationalized dispositionally, in enhanced ASP shown by individuals with fear pathology unaccompanied by distress pathology. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. 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.

  1. What is a hospital bed day worth? A contingent valuation study of hospital Chief Executive Officers.

    Science.gov (United States)

    Page, Katie; Barnett, Adrain G; Graves, Nicholas

    2017-02-14

    Decreasing hospital length of stay, and so freeing up hospital beds, represents an important cost saving which is often used in economic evaluations. The savings need to be accurately quantified in order to make optimal health care resource allocation decisions. Traditionally the accounting cost of a bed is used. We argue instead that the economic cost of a bed day is the better value for making resource decisions, and we describe our valuation method and estimations for costing this important resource. We performed a contingent valuation using 37 Australian Chief Executive Officers' (CEOs) willingness to pay (WTP) to release bed days in their hospitals, both generally and using specific cases. We provide a succinct thematic analysis from qualitative interviews post survey completion, which provide insight into the decision making process. On average CEOs are willing to pay a marginal rate of $216 for a ward bed day and $436 for an Intensive Care Unit (ICU) bed day, with estimates of uncertainty being greater for ICU beds. These estimates are significantly lower (four times for ward beds and seven times for ICU beds) than the traditional accounting costs often used. Key themes to emerge from the interviews include the importance of national funding and targets, and their associated incentive structures, as well as the aversion to discuss bed days as an economic resource. This study highlights the importance for valuing bed days as an economic resource to inform cost effectiveness models and thus improve hospital decision making and resource allocation. Significantly under or over valuing the resource is very likely to result in sub-optimal decision making. We discuss the importance of recognising the opportunity costs of this resource and highlight areas for future research.

  2. Stuttering Thoughts: Negative Self-Referent Thinking Is Less Sensitive to Aversive Outcomes in People with Higher Levels of Depressive Symptoms

    Science.gov (United States)

    Iijima, Yudai; Takano, Keisuke; Boddez, Yannick; Raes, Filip; Tanno, Yoshihiko

    2017-01-01

    Learning theories of depression have proposed that depressive cognitions, such as negative thoughts with reference to oneself, can develop through a reinforcement learning mechanism. This negative self-reference is considered to be positively reinforced by rewarding experiences such as genuine support from others after negative self-disclosure, and negatively reinforced by avoidance of potential aversive situations. The learning account additionally predicts that negative self-reference would be maintained by an inability to adjust one’s behavior when negative self-reference no longer leads to such reward. To test this prediction, we designed an adapted version of the reversal-learning task. In this task, participants were reinforced to choose and engage in either negative or positive self-reference by probabilistic economic reward and punishment. Although participants were initially trained to choose negative self-reference, the stimulus-reward contingencies were reversed to prompt a shift toward positive self-reference (Study 1) and a further shift toward negative self-reference (Study 2). Model-based computational analyses showed that depressive symptoms were associated with a low learning rate of negative self-reference, indicating a high level of reward expectancy for negative self-reference even after the contingency reversal. Furthermore, the difficulty in updating outcome predictions of negative self-reference was significantly associated with the extent to which one possesses negative self-images. These results suggest that difficulty in adjusting action-outcome estimates for negative self-reference increases the chance to be faced with negative aspects of self, which may result in depressive symptoms. PMID:28824511

  3. Stuttering Thoughts: Negative Self-Referent Thinking Is Less Sensitive to Aversive Outcomes in People with Higher Levels of Depressive Symptoms

    Directory of Open Access Journals (Sweden)

    Yudai Iijima

    2017-08-01

    Full Text Available Learning theories of depression have proposed that depressive cognitions, such as negative thoughts with reference to oneself, can develop through a reinforcement learning mechanism. This negative self-reference is considered to be positively reinforced by rewarding experiences such as genuine support from others after negative self-disclosure, and negatively reinforced by avoidance of potential aversive situations. The learning account additionally predicts that negative self-reference would be maintained by an inability to adjust one’s behavior when negative self-reference no longer leads to such reward. To test this prediction, we designed an adapted version of the reversal-learning task. In this task, participants were reinforced to choose and engage in either negative or positive self-reference by probabilistic economic reward and punishment. Although participants were initially trained to choose negative self-reference, the stimulus-reward contingencies were reversed to prompt a shift toward positive self-reference (Study 1 and a further shift toward negative self-reference (Study 2. Model-based computational analyses showed that depressive symptoms were associated with a low learning rate of negative self-reference, indicating a high level of reward expectancy for negative self-reference even after the contingency reversal. Furthermore, the difficulty in updating outcome predictions of negative self-reference was significantly associated with the extent to which one possesses negative self-images. These results suggest that difficulty in adjusting action-outcome estimates for negative self-reference increases the chance to be faced with negative aspects of self, which may result in depressive symptoms.

  4. Stuttering Thoughts: Negative Self-Referent Thinking Is Less Sensitive to Aversive Outcomes in People with Higher Levels of Depressive Symptoms.

    Science.gov (United States)

    Iijima, Yudai; Takano, Keisuke; Boddez, Yannick; Raes, Filip; Tanno, Yoshihiko

    2017-01-01

    Learning theories of depression have proposed that depressive cognitions, such as negative thoughts with reference to oneself, can develop through a reinforcement learning mechanism. This negative self-reference is considered to be positively reinforced by rewarding experiences such as genuine support from others after negative self-disclosure, and negatively reinforced by avoidance of potential aversive situations. The learning account additionally predicts that negative self-reference would be maintained by an inability to adjust one's behavior when negative self-reference no longer leads to such reward. To test this prediction, we designed an adapted version of the reversal-learning task. In this task, participants were reinforced to choose and engage in either negative or positive self-reference by probabilistic economic reward and punishment. Although participants were initially trained to choose negative self-reference, the stimulus-reward contingencies were reversed to prompt a shift toward positive self-reference (Study 1) and a further shift toward negative self-reference (Study 2). Model-based computational analyses showed that depressive symptoms were associated with a low learning rate of negative self-reference, indicating a high level of reward expectancy for negative self-reference even after the contingency reversal. Furthermore, the difficulty in updating outcome predictions of negative self-reference was significantly associated with the extent to which one possesses negative self-images. These results suggest that difficulty in adjusting action-outcome estimates for negative self-reference increases the chance to be faced with negative aspects of self, which may result in depressive symptoms.

  5. Handling Protest Responses in Contingent Valuation Surveys.

    Science.gov (United States)

    Pennington, Mark; Gomes, Manuel; Donaldson, Cam

    2017-08-01

    Protest responses, whereby respondents refuse to state the value they place on the health gain, are commonly encountered in contingent valuation (CV) studies, and they tend to be excluded from analyses. Such an approach will be biased if protesters differ from non-protesters on characteristics that predict their responses. The Heckman selection model has been commonly used to adjust for protesters, but its underlying assumptions may be implausible in this context. We present a multiple imputation (MI) approach to appropriately address protest responses in CV studies, and compare it with the Heckman selection model. This study exploits data from the multinational EuroVaQ study, which surveyed respondents' willingness-to-pay (WTP) for a Quality Adjusted Life Year (QALY). Here, our simulation study assesses the relative performance of MI and Heckman selection models across different realistic settings grounded in the EuroVaQ study, including scenarios with different proportions of missing data and non-response mechanisms. We then illustrate the methods in the EuroVaQ study for estimating mean WTP for a QALY gain. We find that MI provides lower bias and mean squared error compared with the Heckman approach across all considered scenarios. The simulations suggest that the Heckman approach can lead to considerable underestimation or overestimation of mean WTP due to violations in the normality assumption, even after log-transforming the WTP responses. The case study illustrates that protesters are associated with a lower mean WTP for a QALY gain compared with non-protesters, but that the results differ according to method for handling protesters. MI is an appropriate method for addressing protest responses in CV studies.

  6. Social comparisons, appearance related comments, contingent self-esteem and their relationships with body dissatisfaction and eating disturbance among women.

    Science.gov (United States)

    Bailey, Shannon D; Ricciardelli, Lina A

    2010-04-01

    This study examined social comparisons, appearance related comments and contingent self-esteem, and their relationships with body dissatisfaction and eating disturbance in young adult women. Importantly, the role of both positive and negative appearance related comments, and upward and downward comparisons, were investigated. A self-report questionnaire assessing each of these variables was completed by one hundred and ninety-six women aged 18-35. A higher frequency of negative comments and contingent self-esteem were associated with higher upward comparisons, and more positive comments were associated with higher downward comparisons. Overall, social comparisons were shown to be more important than verbal commentary and contingent self-esteem. More upward comparisons and less downward comparisons uniquely predicted higher body dissatisfaction and eating disturbance. In addition, negative appearance comments were found to be more salient than positive comments. Negative comments and contingent self-esteem uniquely predicted more eating disturbance but positive comments were not a predictor of body dissatisfaction or eating disturbance. Longitudinal studies are now required to establish the direction of these relationships and to more fully examine the interplay among the factors. In addition, given that our study only assessed self-reported social comparisons, our findings need to be validated against experimental methods. Copyright 2009 Elsevier Ltd. All rights reserved.

  7. Dengue Contingency Planning: From Research to Policy and Practice

    Science.gov (United States)

    Runge-Ranzinger, Silvia; Kroeger, Axel; Olliaro, Piero; McCall, Philip J.; Sánchez Tejeda, Gustavo; Lloyd, Linda S.; Hakim, Lokman; Bowman, Leigh R.; Horstick, Olaf; Coelho, Giovanini

    2016-01-01

    Background Dengue is an increasingly incident disease across many parts of the world. In response, an evidence-based handbook to translate research into policy and practice was developed. This handbook facilitates contingency planning as well as the development and use of early warning and response systems for dengue fever epidemics, by identifying decision-making processes that contribute to the success or failure of dengue surveillance, as well as triggers that initiate effective responses to incipient outbreaks. Methodology/Principal findings Available evidence was evaluated using a step-wise process that included systematic literature reviews, policymaker and stakeholder interviews, a study to assess dengue contingency planning and outbreak management in 10 countries, and a retrospective logistic regression analysis to identify alarm signals for an outbreak warning system using datasets from five dengue endemic countries. Best practices for managing a dengue outbreak are provided for key elements of a dengue contingency plan including timely contingency planning, the importance of a detailed, context-specific dengue contingency plan that clearly distinguishes between routine and outbreak interventions, surveillance systems for outbreak preparedness, outbreak definitions, alert algorithms, managerial capacity, vector control capacity, and clinical management of large caseloads. Additionally, a computer-assisted early warning system, which enables countries to identify and respond to context-specific variables that predict forthcoming dengue outbreaks, has been developed. Conclusions/Significance Most countries do not have comprehensive, detailed contingency plans for dengue outbreaks. Countries tend to rely on intensified vector control as their outbreak response, with minimal focus on integrated management of clinical care, epidemiological, laboratory and vector surveillance, and risk communication. The Technical Handbook for Surveillance, Dengue Outbreak

  8. 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.

  9. Contingency Contractor Optimization Phase 3 Sustainment Platform Requirements - Contingency Contractor Optimization Tool - Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Durfee, Justin David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Frazier, Christopher Rawls [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bandlow, Alisa [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gearhart, Jared Lee [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jones, Katherine A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-06-01

    Sandia National Laboratories (Sandia) is in Phase 3 Sustainment of development of a prototype tool, currently referred to as the Contingency Contractor Optimization Tool - Prototype (CCOTP), under the direction of OSD Program Support. CCOT-P is intended to help provide senior Department of Defense (DoD) leaders with comprehensive insight into the global availability, readiness and capabilities of the Total Force Mix. The CCOT-P will allow senior decision makers to quickly and accurately assess the impacts, risks and mitigating strategies for proposed changes to force/capabilities assignments, apportionments and allocations options, focusing specifically on contingency contractor planning. During Phase 2 of the program, conducted during fiscal year 2012, Sandia developed an electronic storyboard prototype of the Contingency Contractor Optimization Tool that can be used for communication with senior decision makers and other Operational Contract Support (OCS) stakeholders. Phase 3 used feedback from demonstrations of the electronic storyboard prototype to develop an engineering prototype for planners to evaluate. Sandia worked with the DoD and Joint Chiefs of Staff strategic planning community to get feedback and input to ensure that the engineering prototype was developed to closely align with future planning needs. The intended deployment environment was also a key consideration as this prototype was developed. Initial release of the engineering prototype was done on servers at Sandia in the middle of Phase 3. In 2013, the tool was installed on a production pilot server managed by the OUSD(AT&L) eBusiness Center. The purpose of this document is to specify the CCOT-P engineering prototype platform requirements as of May 2016. Sandia developed the CCOT-P engineering prototype using common technologies to minimize the likelihood of deployment issues. CCOT-P engineering prototype was architected and designed to be as independent as possible of the major deployment

  10. School management and contingency theory: an emerging perspective.

    Science.gov (United States)

    Hanson, E M

    1979-01-01

    In an article written for educational administrators, Hanson explains the assumptions, framework, and application of contingency theory. The author sees contingency theory as a way for organizations to adapt to uncertainty by developing a strategic plan with alternative scenarios. He urges school administrators to join businessmen and public managers in using a technique described as "the most powerful current sweeping over the organizational field." The theory assumes that: (1) a maze of goals govern the development of events; (2) different management approaches may be appropriate within the same organization; and (3) different leadership styles suit different situations. Contingency planning helps the organization to respond to uncertainty in the external environment by identifying possible events that may occur and by preparing alternative stratgies to deal with them. Hanson describes the purpose of this process as providing "a more effective match between an organization and its environment." He explains that contingency theory analyzes the internal adjustments of the organization (e.g., decision making process, structure, technology, instructional techniques) as it seeks to meet the shifting demands of its external or internal environments. According to the author, the intent of contingency theory is to establish an optimal "match" between environmental demands (and support) and the response capabilities of the organization including its structure, planning process, and leadership style.

  11. Effects of sensitization on the detection of an instrumental contingency.

    Science.gov (United States)

    Phillips, Gavin D; Vugler, Anthony

    2011-11-01

    While prior exposure to drugs of abuse permanently changes many behaviors, the underlying psychological mechanisms are relatively obscure. Here, the effects of sensitization on the detection of an action-outcome relationship were assessed, using a particularly stringent contingency degradation procedure. Rats were trained to leverpress until the probability of reinforcement for a response on one lever, or alternative reinforcement for a response on a second lever was reduced to 0.05 per second. Sensitization was then carried out (1mg/kg d-amphetamine/day for 7 days). Then, one reinforcer was also made available for a lack of response on either lever (p=0.05/s), maintaining its contiguity with the original response but eliminating its contingent relationship. Sensitized animals were more active, particularly early in the contingency degradation phase, but reduced responding directed at the degraded action-outcome contingency at a similar rate as controls. However, controls also reduced responding directed at the nondegraded contingency until very late in training, while sensitized animals maintained nondegraded responding at baseline levels. It was suggested that the relatively specific response shown by sensitized animals may reflect either improved action-outcome utilization or discrimination of relevant task features.

  12. 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

  13. Midazolam impairs the retrieval of conditioned taste aversion via opioidergic transmission in mice.

    Science.gov (United States)

    Yasoshima, Yasunobu; Shimura, Tsuyoshi

    2017-01-01

    Midazolam is a benzodiazepine agonist that affects the acquisition, retention, and retrieval of malaise-induced conditioned taste aversion (CTA) in rats. Our previous study suggested that the palatability-enhancing rather than amnesic effects of midazolam were responsible for impaired retrieval of conditioned aversion to palatable conditioned stimuli (CSs). However, it remains unclear whether this effect is opioid-dependent. In the present study, we examined the involvement of opioid signaling with the ability of peripheral midazolam administration to transiently impair CTA retrieval in mice. CTA was established by pairing 5mM saccharin ingestion (conditioned stimulus, CS) with an intraperitoneal (i.p.) injection of 0.15M lithium chloride (LiCl, 2% body weight) (unconditioned stimulus) for two consecutive days. Conditioned mice that received midazolam (1.5mg/kg, i.p.) before the first retention test consumed significantly more saccharin (CS) than conditioned mice that received vehicle (phosphate-buffered physiological saline, PBS; i.p.). On the next day, both conditioned groups showed strong aversions to the CS. Next, naloxone, an opioid receptor antagonist, was peripherally administered prior to the midazolam injection before the retention test. Pre-administration of naloxone but not PBS attenuated midazolam-induced increases in CS intake. Finally, we examined aversive orofacial taste reactions (TRs) to an oral infusion of the CS with pre-administration of naloxone or PBS prior to midazolam using a taste reactivity test. Conditioned mice that received midazolam showed significantly longer latencies to express aversive orofacial TRs than those that received PBS. Pre-administration of naloxone eliminated the effect of midazolam on latency to express aversive TRs. Taken together, these data suggest that midazolam activates opioidergic transmission and opioid-dependent palatability enhancement of the CS to eliminate conditioned aversion to a sweet taste. Copyright

  14. Effect of risk aversion on prioritizing conservation projects.

    Science.gov (United States)

    Tulloch, Ayesha I T; Maloney, Richard F; Joseph, Liana N; Bennett, Joseph R; Di Fonzo, Martina M I; Probert, William J M; O'Connor, Shaun M; Densem, Jodie P; Possingham, Hugh P

    2015-04-01

    Conservation outcomes are uncertain. Agencies making decisions about what threat mitigation actions to take to save which species frequently face the dilemma of whether to invest in actions with high probability of success and guaranteed benefits or to choose projects with a greater risk of failure that might provide higher benefits if they succeed. The answer to this dilemma lies in the decision maker's aversion to risk--their unwillingness to accept uncertain outcomes. Little guidance exists on how risk preferences affect conservation investment priorities. Using a prioritization approach based on cost effectiveness, we compared 2 approaches: a conservative probability threshold approach that excludes investment in projects with a risk of management failure greater than a fixed level, and a variance-discounting heuristic used in economics that explicitly accounts for risk tolerance and the probabilities of management success and failure. We applied both approaches to prioritizing projects for 700 of New Zealand's threatened species across 8303 management actions. Both decision makers' risk tolerance and our choice of approach to dealing with risk preferences drove the prioritization solution (i.e., the species selected for management). Use of a probability threshold minimized uncertainty, but more expensive projects were selected than with variance discounting, which maximized expected benefits by selecting the management of species with higher extinction risk and higher conservation value. Explicitly incorporating risk preferences within the decision making process reduced the number of species expected to be safe from extinction because lower risk tolerance resulted in more species being excluded from management, but the approach allowed decision makers to choose a level of acceptable risk that fit with their ability to accommodate failure. We argue for transparency in risk tolerance and recommend that decision makers accept risk in an adaptive management

  15. Psychophysical and Neural Correlates of Auditory Attraction and Aversion

    Science.gov (United States)

    Patten, Kristopher Jakob

    This study explores the psychophysical and neural processes associated with the perception of sounds as either pleasant or aversive. The underlying psychophysical theory is based on auditory scene analysis, the process through which listeners parse auditory signals into individual acoustic sources. The first experiment tests and confirms that a self-rated pleasantness continuum reliably exists for 20 various stimuli (r = .48). In addition, the pleasantness continuum correlated with the physical acoustic characteristics of consonance/dissonance (r = .78), which can facilitate auditory parsing processes. The second experiment uses an fMRI block design to test blood oxygen level dependent (BOLD) changes elicited by a subset of 5 exemplar stimuli chosen from Experiment 1 that are evenly distributed over the pleasantness continuum. Specifically, it tests and confirms that the pleasantness continuum produces systematic changes in brain activity for unpleasant acoustic stimuli beyond what occurs with pleasant auditory stimuli. Results revealed that the combination of two positively and two negatively valenced experimental sounds compared to one neutral baseline control elicited BOLD increases in the primary auditory cortex, specifically the bilateral superior temporal gyrus, and left dorsomedial prefrontal cortex; the latter being consistent with a frontal decision-making process common in identification tasks. The negatively-valenced stimuli yielded additional BOLD increases in the left insula, which typically indicates processing of visceral emotions. The positively-valenced stimuli did not yield any significant BOLD activation, consistent with consonant, harmonic stimuli being the prototypical acoustic pattern of auditory objects that is optimal for auditory scene analysis. Both the psychophysical findings of Experiment 1 and the neural processing findings of Experiment 2 support that consonance is an important dimension of sound that is processed in a manner that aids

  16. Aversive stimuli exacerbate defensive motor behaviour in motor conversion disorder.

    Science.gov (United States)

    Blakemore, Rebekah L; Sinanaj, Indrit; Galli, Silvio; Aybek, Selma; Vuilleumier, Patrik

    2016-12-01

    Conversion disorder or functional neurological symptom disorder (FND) can affect the voluntary motor system, without an organic cause. Functional symptoms are thought to be generated unconsciously, arising from underlying psychological stressors. However, attempts to demonstrate a direct relationship between the limbic system and disrupted motor function in FND are lacking. We tested whether negative affect would exacerbate alterations of motor control and corresponding brain activations in individuals with FND. Ten patients and ten healthy controls produced an isometric precision-grip contraction at 10% of maximum force while either viewing visual feedback of their force output, or unpleasant or pleasant emotional images (without feedback). Force magnitude was continuously recorded together with change in brain activity using fMRI. For controls, force output decayed from the target level while viewing pleasant and unpleasant images. Patients however, maintained force at the target level without decay while viewing unpleasant images, indicating a pronounced effect of negative affect on force output in FND. This emotional modulation of force control was associated with different brain activation patterns between groups. Contrasting the unpleasant with the pleasant condition, controls showed increased activity in the inferior frontal cortex and pre-supplementary motor area, whereas patients had greater activity in the cerebellum (vermis), posterior cingulate cortex, and hippocampus. Engagement of a cerebellar-limbic network in patients is consistent with heightened processing of emotional salience, and supports the role of the cerebellum in freezing responses in the presence of aversive events. These data highlight a possible neural circuit through which psychological stressors elicit defensive behaviour and modulate motor function in FND. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Aversive conditioning in honey bees (Apis mellifera anatolica): a comparison of drones and workers.

    Science.gov (United States)

    Dinges, Christopher W; Avalos, Arian; Abramson, Charles I; Craig, David Philip Arthur; Austin, Zoe M; Varnon, Christopher A; Dal, Fatima Nur; Giray, Tugrul; Wells, Harrington

    2013-11-01

    Honey bees provide a model system to elucidate the relationship between sociality and complex behaviors within the same species, as females (workers) are highly social and males (drones) are more solitary. We report on aversive learning studies in drone and worker honey bees (Apis mellifera anatolica) in escape, punishment and discriminative punishment situations. In all three experiments, a newly developed electric shock avoidance assay was used. The comparisons of expected and observed responses were performed with conventional statistical methods and a systematic randomization modeling approach called object oriented modeling. The escape experiment consisted of two measurements recorded in a master-yoked paradigm: frequency of response and latency to respond following administration of shock. Master individuals could terminate an unavoidable shock triggered by a decrementing 30 s timer by crossing the shuttlebox centerline following shock activation. Across all groups, there was large individual response variation. When assessing group response frequency and latency, master subjects performed better than yoked subjects for both workers and drones. In the punishment experiment, individuals were shocked upon entering the shock portion of a bilaterally wired shuttlebox. The shock portion was spatially static and unsignalled. Only workers effectively avoided the shock. The discriminative punishment experiment repeated the punishment experiment but included a counterbalanced blue and yellow background signal and the side of shock was manipulated. Drones correctly responded less than workers when shock was paired with blue. However, when shock was paired with yellow there was no observable difference between drones and workers.

  18. Why Women Are Averse to Facility Delivery in Northwest Nigeria: A Qualitative Inquiry

    Directory of Open Access Journals (Sweden)

    *Ismail TUKUR

    2016-05-01

    Full Text Available Background: In many sub-Saharan African countries the rate of antenatal care (ANC has been increased but skilled birth attendance rate is still low. The objective of this study was to evaluate the reasons why women prefer home delivery when facility based delivery is available at minimal cost.Methods: This study was conducted in Northwest Nigeria using a qualitative method (phenomenology among five categories of women in April – May 2013. This study investigated different categories of women (those that never attend ANC nor deliver in the facility, those that attend ANC but delivered at home and those that delivered once in the facility but fail to return in subsequent deliveries, the in-laws and facilities staff.Results: Through focus group discussions and In-depth interviews several reasons why women are averse to hospital deliveries were identified. Women reported ignorance, abuse, illiteracy, and poverty, and low esteem, poor attitude of health workers, few working hours and some integrated health services like preventing mother to child transmission of HIV testing as deterrents, while cheap and accessible services were reasons for preference to traditional birth attendants.Conclusions: The findings highlighted important entrenched barriers to facility deliveries among women, which is basically socio-cultural and economic. Therefore emphasis must be given to health education program to ensure comprehensive and target specific messages that will address individual needs of the groups. Keywords: Barriers, Hospital delivery, Qualitative inquiry, Northwest Nigeria

  19. Negotiating contingent knowledges in a time of epistemic doubt

    DEFF Research Database (Denmark)

    Phillips, Louise Jane

    How can/should we produce and communicate social scientific knowledge with authority under conditions of epistemic doubt? If all knowledge is contingent and if truth is a discursive effect rather than the final claim about reality - as post-foundationalism suggests - how can we formulate...... and provide support for contingent knowledge-claims? And how can the communication of social scientificknowlege be theorised and practised as the negotiation between social scientific knowledge and other forms of contingent knowledge rather than the one-way transmission of universal, value-free truth......-claims? In the paper, I outline an approach to addressing the final question. The approach is based on a combination of approaches to the production of knowledge developed in post-foundationalist sociology and philosophy of science, approaches to the communication of knowlege developed within communication studies...

  20. Why projects often fail even with high cost contingencies

    Energy Technology Data Exchange (ETDEWEB)

    Kujawski, Edouard

    2002-02-28

    In this note we assume that the individual risks have been adequately quantified and the total project cost contingency adequately computed to ensure an agreed-to probability or confidence level that the total project cost estimate will not be exceeded. But even projects that implement such a process are likely to result in significant cost overruns and/or project failure if the project manager allocates the contingencies to the individual subsystems. The intuitive and mathematically valid solution is to maintain a project-wide contingency and to distribute it to the individual risks on an as-needed basis. Such an approach ensures cost-efficient risk management, and projects that implement it are more likely to succeed and to cost less. We illustrate these ideas using a simplified project with two independent risks. The formulation can readily be extended to multiple risks.

  1. Volcanic Eruption: Students Develop a Contingency Plan

    Science.gov (United States)

    Meisinger, Philipp; Wittlich, Christian

    2013-04-01

    , causing a blockage and afflux of the Rhine, which, due to the given conditions of a very narrow valley, would lead to excessive flooding affecting even the greater Rhine-Main-region. Not to mention the consequences of a pyroclastic flow, dropping volcanic bombs and further hazardous/disastrous consequences. In comparison to other "potentially active" or "active volcanoes", e.g. the Vesuvius, the Laacher See is scarcely monitored and according to recent publications poorly analyzed in terms of contingency and evacuation plans. This offers space for critical analysis and creative solutions to an existing problem. Short: We need geographers and their knowledge to provide help. Given these facts, the Laacher See could be the layout for a very interesting geography project bringing together previously gained knowledge and understanding of volcanic activities, their destructive powers, consequences and risks in case of an eruption in combination with their topographical characteristics. Your students thereby act the role of a geoscientist developing contingency plans and evacuation zones for the greater Laacher See area. This involves a detailed analysis of the topographical characteristics based on (classic) topographic maps or online via the use of a GIS (e.g. Google maps). In a second step students enlist the possible consequences they already know according to their range and copy them onto a transparency layer on the topographic map. Using such a layer technique students add population density, important topographic features and maybe even anticipated wind directions to their map. The information density and the specific layout of this map are thereby only determined by the student's previous knowledge, their personal abilities and skills and the amount of time provided. This offers the opportunities to even differentiate the task within your group and provide support adjusted to the individual students level. On the basis of their own thematic map your students should be

  2. Contingency table techniques for three dimensional atom probe tomography.

    Science.gov (United States)

    Moody, Michael P; Stephenson, Leigh T; Liddicoat, Peter V; Ringer, Simon P

    2007-03-01

    A contingency table analysis procedure is developed and applied to three dimensional atom probe data sets for the investigation of fine-scale solute co-/anti-segregation effects in multicomponent alloys. Potential sources of error and inaccuracy are identified and eliminated from the technique. The conventional P value testing techniques associated with chi(2) are shown to be unsatisfactory and can become ambiguous in cases of large block numbers or high solute concentrations. The coefficient of contingency is demonstrated to be an acceptable and useful basis of comparison for contingency table analyses of differently-conditioned materials. However, care must be taken in choice of block size and to maintain a consistent overall composition between experiments. The coefficient is dependent upon block size and solute composition, and cannot be used to compare analyses with significantly different solute compositions or to assess the extent of clustering without reference to that of the randomly ordered case. It is shown that as clustering evolves into larger precipitates and phases, contingency table analysis becomes inappropriate. Random labeling techniques are introduced to infer further meaning from the coefficient of contingency. We propose the comparison of experimental result, mu(exp), to the randomized value, micro(rand), as a new method by which to interpret the quantity of solute clustering present in a material. It is demonstrated that how this method may be utilized to identify an appropriate size of contingency table analysis blocks into which the data set is partitioned to optimize the significance of the results. (c) 2007 Wiley-Liss, Inc.

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

    Directory of Open Access Journals (Sweden)

    Steven John Shabel

    2014-01-01

    Full Text Available 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 towards 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.

  4. Midbrain dopamine neurons signal aversion in a reward-context-dependent manner

    Science.gov (United States)

    Matsumoto, Hideyuki; Tian, Ju; Uchida, Naoshige; Watabe-Uchida, Mitsuko

    2016-01-01

    Dopamine is thought to regulate learning from appetitive and aversive events. Here we examined how optogenetically-identified dopamine neurons in the lateral ventral tegmental area of mice respond to aversive events in different conditions. In low reward contexts, most dopamine neurons were exclusively inhibited by aversive events, and expectation reduced dopamine neurons’ responses to reward and punishment. When a single odor predicted both reward and punishment, dopamine neurons’ responses to that odor reflected the integrated value of both outcomes. Thus, in low reward contexts, dopamine neurons signal value prediction errors (VPEs) integrating information about both reward and aversion in a common currency. In contrast, in high reward contexts, dopamine neurons acquired a short-latency excitation to aversive events that masked their VPE signaling. Our results demonstrate the importance of considering the contexts to examine the representation in dopamine neurons and uncover different modes of dopamine signaling, each of which may be adaptive for different environments. DOI: http://dx.doi.org/10.7554/eLife.17328.001 PMID:27760002

  5. 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.

  6. Taste aversion learning and aging: a comparison with the effect of dorsal hippocampal lesions in rats.

    Science.gov (United States)

    Moron, I; Ballesteros, M A; Candido, A; Gallo, M

    2002-01-01

    The relationship between hippocampal function and aging was explored in Wistar rats using taste aversion learning by comparing the performance of adult dorsal hippocampal lesioned and fifteen-month-old intact rats with that of adult intact rats. In experiment 1 the conditioned blocking phenomenon was absent in the hippocampal and the aging rats. Unlike the adult intact rats, the hippocampal and aging rats were not impaired in acquiring a learned aversion to a cider vinegar solution (3 %) presented as a serial compound with a previously conditioned saccharin solution (0.1 %). In experiment 2 both the hippocampal and the aging rats developed reduced aversions to a saline solution (0.5 %) followed by an i.p. injection of lithium chloride (0.15 M; 2 % b.w.) if the taste solution was previously preexposed without consequences. This latent inhibition effect was similar to that seen in intact adult rats. In both experiments, the aging rats exhibited enhanced conventional learned taste aversions. It is concluded that aging is not a unitary process but induces both hippocampal dependent and hippocampal independent complex changes in the functioning of the neural circuits, implementing taste aversion learning.

  7. 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.

  8. Genotypic influence on aversive conditioning in honeybees, using a novel thermal reinforcement procedure.

    Directory of Open Access Journals (Sweden)

    Pierre Junca

    Full Text Available 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.

  9. Cultural capital or relative risk aversion? Two mechanisms for educational inequality compared.

    Science.gov (United States)

    van de Werfhorst, Herman G; Hofstede, Saskia

    2007-09-01

    In this paper we empirically examined two explanatory mechanisms for educational inequality: cultural reproduction and relative risk aversion, using survey data taken from secondary school pupils in Amsterdam. Cultural reproduction theory seeks to explain class variations in schooling by cultural differences between social classes. Relative risk aversion theory argues that educational inequalities can be understood by between-class variation in the necessity of pursuing education at branching points in order to avoid downward mobility. We showed that class variations in early demonstrated ability are for a substantial part cultural: cultural capital - measured by parental involvement in highbrow culture - affected school performance at the primary and secondary level. However, relative risk aversion - operationalized by being concerned with downward mobility - strongly affects schooling ambitions, whereas cultural capital had no effect. Thus, we conclude that 'primary effects' of social origin on schooling outcomes are manifested through cultural capital and not through relative risk aversion (in addition to other potential sources of class variations such as genetics). Relative risk aversion, and not cultural capital, affects schooling ambitions, which is relevant for our understanding of secondary effects.

  10. Organization of neural systems for aversive information processing: pain, error, and punishment

    Directory of Open Access Journals (Sweden)

    Shunsuke eKobayashi

    2012-09-01

    Full Text Available The avoidance of aversive events is critically important for the survival of organisms. It has been proposed that the medial pain system, including the amygdala, periaqueductal gray (PAG, and anterior cingulate cortex (ACC, contains the neural circuitry that signals pain affect and negative value. This system appears to have multiple defense mechanisms, such as rapid stereotyped escape, aversive association learning, and cognitive adaptation. These defense mechanisms vary in speed and flexibility, reflecting different strategies of self-protection. Over the course of evolution, the medial pain system appears to have developed primitive, associative, and cognitive solutions for aversive avoidance. There may be a functional grading along the caudal-rostral axis, such that the amygdala-PAG system underlies automatic and autonomic responses, the amygdala-orbitofrontal system contributes to associative learning, and the ACC controls cognitive processes in cooperation with the lateral prefrontal cortex. A review of behavioral and physiological studies on the aversive system is presented, and a conceptual framework for understanding the neural organization of the aversive avoidance system is proposed.

  11. Development of an Aversive Pavlovian-to-Instrumental Transfer Task in Rat

    Directory of Open Access Journals (Sweden)

    Vincent eCampese

    2013-11-01

    Full Text Available Pavlovian-to-instrumental transfer (PIT is an effect whereby a classically conditioned stimulus (CS enhances ongoing instrumental responding. PIT has been extensively studied with appetitive conditioning but barely at all with aversive conditioning. Although it’s been argued that conditioned suppression is a form of aversive PIT, this effect is fundamentally different from appetitive PIT because the CS suppresses, instead of facilitates, responding. Five experiments investigated the importance of a variety of factors on aversive PIT in a rodent Sidman avoidance paradigm in which ongoing shuttling behavior was facilitated by an aversive CS. Experiment 1 demonstrated a basic PIT effect. Experiment 2 found that a moderate amount of USAA extinction produces the strongest PIT with shuttling rates best at around 2 responses per minute prior to the CS. Experiment 3 tested a protocol in which the USAA behavior was required to reach the 2-response per minute mark in order to trigger the CS presentation and found that this produced robust and reliable PIT. Experiment 4 found that the Pavlovian conditioning US intensity was not a major determinant of PIT strength. Experiment 5 demonstrated that if the CS and US were not explicitly paired during Pavlovian conditioning, PIT did not occur, showing that CS-US learning is required. Together, these studies demonstrate a robust, reliable and stable aversive PIT effect that is amenable to analysis of neural circuitry.

  12. Development of an aversive Pavlovian-to-instrumental transfer task in rat.

    Science.gov (United States)

    Campese, Vincent; McCue, Margaret; Lázaro-Muñoz, Gabriel; Ledoux, Joseph E; Cain, Christopher K

    2013-01-01

    Pavlovian-to-instrumental transfer (PIT) is an effect whereby a classically conditioned stimulus (CS) enhances ongoing instrumental responding. PIT has been extensively studied with appetitive conditioning but barely at all with aversive conditioning. Although it's been argued that conditioned suppression is a form of aversive PIT, this effect is fundamentally different from appetitive PIT because the CS suppresses, instead of facilitates, responding. Five experiments investigated the importance of a variety of factors on aversive PIT in a rodent Sidman avoidance paradigm in which ongoing shuttling behavior (unsignaled active avoidance or USAA) was facilitated by an aversive CS. Experiment 1 demonstrated a basic PIT effect. Experiment 2 found that a moderate amount of USAA extinction produces the strongest PIT with shuttling rates best at around 2 responses per minute prior to the CS. Experiment 3 tested a protocol in which the USAA behavior was required to reach the 2-response per minute mark in order to trigger the CS presentation and found that this produced robust and reliable PIT. Experiment 4 found that the Pavlovian conditioning US intensity was not a major determinant of PIT strength. Experiment 5 demonstrated that if the CS and US were not explicitly paired during Pavlovian conditioning, PIT did not occur, showing that CS-US learning is required. Together, these studies demonstrate a robust, reliable and stable aversive PIT effect that is amenable to analysis of neural circuitry.

  13. Aversive learning in honeybees revealed by the olfactory conditioning of the sting extension reflex.

    Directory of Open Access Journals (Sweden)

    Vanina Vergoz

    Full Text Available Invertebrates have contributed greatly to our understanding of associative learning because they allow learning protocols to be combined with experimental access to the nervous system. The honeybee Apis mellifera constitutes a standard model for the study of appetitive learning and memory since it was shown, almost a century ago, that bees learn to associate different sensory cues with a reward of sugar solution. However, up to now, no study has explored aversive learning in bees in such a way that simultaneous access to its neural bases is granted. Using odorants paired with electric shocks, we conditioned the sting extension reflex, which is exhibited by harnessed bees when subjected to a noxious stimulation. We show that this response can be conditioned so that bees learn to extend their sting in response to the odorant previously punished. Bees also learn to extend the proboscis to one odorant paired with sugar solution and the sting to a different odorant paired with electric shock, thus showing that they can master both appetitive and aversive associations simultaneously. Responding to the appropriate odorant with the appropriate response is possible because two different biogenic amines, octopamine and dopamine subserve appetitive and aversive reinforcement, respectively. While octopamine has been previously shown to substitute for appetitive reinforcement, we demonstrate that blocking of dopaminergic, but not octopaminergic, receptors suppresses aversive learning. Therefore, aversive learning in honeybees can now be accessed both at the behavioral and neural levels, thus opening new research avenues for understanding basic mechanisms of learning and memory.

  14. Is avoiding an aversive outcome rewarding? Neural substrates of avoidance learning in the human brain.

    Science.gov (United States)

    Kim, Hackjin; Shimojo, Shinsuke; O'Doherty, John P

    2006-07-01

    Avoidance learning poses a challenge for reinforcement-based theories of instrumental conditioning, because once an aversive outcome is successfully avoided an individual may no longer experience extrinsic reinforcement for their behavior. One possible account for this is to propose that avoiding an aversive outcome is in itself a reward, and thus avoidance behavior is positively reinforced on each trial when the aversive outcome is successfully avoided. In the present study we aimed to test this possibility by determining whether avoidance of an aversive outcome recruits the same neural circuitry as that elicited by a reward itself. We scanned 16 human participants with functional MRI while they performed an instrumental choice task, in which on each trial they chose from one of two actions in order to either win money or else avoid losing money. Neural activity in a region previously implicated in encoding stimulus reward value, the medial orbitofrontal cortex, was found to increase, not only following receipt of reward, but also following successful avoidance of an aversive outcome. This neural signal may itself act as an intrinsic reward, thereby serving to reinforce actions during instrumental avoidance.

  15. Development of a Contingency Capillary Wastewater Management Device

    Science.gov (United States)

    Thomas, Evan A.

    2010-01-01

    The Personal Body .Attached Liquid Liquidator (PBALL) is conceived as a passive, capillary driven contingency wastewater disposal device. In this contingency scenario, the airflow system on the NASA Crew Exploration Vehicle (CEV) is assumed to have failed, leaving only passive hardware and vacuum vent to dispose of the wastewater. To meet these needs, the PBALL was conceived to rely on capillary action and urine wetting design considerations. The PBALL is designed to accommodate a range of wetting conditions, from 0deg wastewater to vacuum while minimizing cabin air loss. A sub-scale PBALL test article was demonstrated on NASA's reduced gravity aircraft in April, 2010.

  16. 78 FR 48844 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List...

    Science.gov (United States)

    2013-08-12

    ... AGENCY 40 CFR Part 300 National Oil and Hazardous Substances Pollution Contingency Plan; National... amended, is an appendix of the National Oil and Hazardous Substances Pollution Contingency Plan (NCP). The... 300 Environmental protection, Air pollution control, Chemicals, Hazardous waste, Hazardous...

  17. 75 FR 26166 - National Oil and Hazardous Substance Pollution Contingency Plan National Priorities List

    Science.gov (United States)

    2010-05-11

    ... AGENCY 40 CFR Part 300 National Oil and Hazardous Substance Pollution Contingency Plan National... 40 CFR part 300 which is the National Oil and Hazardous Substances Pollution Contingency Plan (NCP... 300 Environmental protection, Air pollution control, Chemicals, Hazardous waste, Hazardous...

  18. 78 FR 45167 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List...

    Science.gov (United States)

    2013-07-26

    ... AGENCY 40 CFR Part 300 National Oil and Hazardous Substances Pollution Contingency Plan; National... appendix of the National Oil and Hazardous Substances Pollution Contingency Plan (NCP). The EPA and the... protection, Air pollution control, Chemicals, Hazardous waste, Hazardous substances,...

  19. 78 FR 65210 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List...

    Science.gov (United States)

    2013-10-31

    ... AGENCY 40 CFR Part 300 National Oil and Hazardous Substances Pollution Contingency Plan; National... National Oil and Hazardous Substances Pollution Contingency Plan (NCP). The EPA and the State of California... 300 Environmental protection, Air pollution control, Chemicals, Hazardous waste, Hazardous...

  20. 78 FR 49993 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List...

    Science.gov (United States)

    2013-08-16

    ... AGENCY 40 CFR Part 300 National Oil and Hazardous Substances Pollution Contingency Plan; National..., as amended, is an appendix of the National Oil and Hazardous Substances Pollution Contingency Plan... pollution control, Chemicals, Hazardous waste, Hazardous substances, Intergovernmental relations,...

  1. Does exclusion of protest zeros and warm-glow bidders cause selection bias in Contingent Valuation?

    DEFF Research Database (Denmark)

    Grammatikopoulou, Ioanna; Olsen, Søren Bøye; Pouta, Eija

    A great issue of concern in valuation studies is whether respondents provide trustworthy and reliable answers conditional on the perceived information. Respondent may report either a higher than the true Willingness-To-Pay (WTP) due to warm glow or embedding effects or zero WTP which is lower than...... the true WTP due to protest behavior. We conduct a contingent valuation study to estimate the WTP for conserving a Natura 2000 wetland area in Greece. We find that 54% of the positive bidders exert warm glow motivations while 29% of all responses can be classified as protest zero bids. We employ three...

  2. Flavor aversion learning induced by lithium chloride in reptiles but not in amphibians.

    Science.gov (United States)

    Paradis, Sébastien; Cabanac, Michel

    2004-07-30

    Flavor aversion learning occurs when digestive illness follows ingestion of a novel food. Such learning has been shown to exist in mammals and birds. In this experiment, we looked for flavor aversion learning in amphibians (Bufo paracnemis, Pachytriton breviceps) and reptiles (Basiliscus vitattus, B. basiliscus, Eumeces schneideri, Mabuya multifasciata). After intake of the novel food, the animals received i.p. injection of either lithium chloride (LiCl), an effective illness inducer, or a saline solution. A week later, the LiCl injection had not affected the food intake of the amphibians whereas in the lizards it had produced a strong aversion to the flavor of the novel food. These results are consistent with the hypothesis that specific mental capacities emerged with reptiles.

  3. Estimating risk aversion, Risk-Neutral and Real-World Densities using Brazilian Real currency options

    Directory of Open Access Journals (Sweden)

    José Fajardo

    2012-12-01

    Full Text Available This paper uses the Liu et al. (2007 approach to estimate the optionimplied Risk-Neutral Densities (RND, real-world density (RWD, and relative risk aversion from the Brazilian Real/US Dollar exchange rate distribution. Our empirical application uses a sample of exchange-traded Brazilian Real currency options from 1999 to 2011. Our estimated value of the relative risk aversion is around 2.7, which is in line with other articles for the Brazilian Economy. Our out-of-sample results showed that the RND has some ability to forecast the Brazilian Real exchange rate, but when we incorporate the risk aversion, the out-of-sample performance improves substantially.

  4. Enhanced extinction of aversive memories by high-frequency stimulation of the rat infralimbic cortex.

    Directory of Open Access Journals (Sweden)

    Mouna Maroun

    Full Text Available Electrical stimulation of the rodent medial prefrontal cortex (mPFC, including the infralimbic cortex (IL, immediately prior to or during fear extinction training facilitates extinction memory. Here we examined the effects of high-frequency stimulation (HFS of the rat IL either prior to conditioning or following retrieval of the conditioned memory, on extinction of Pavlovian fear and conditioned taste aversion (CTA. IL-HFS applied immediately after fear memory retrieval, but not three hours after retrieval or prior to conditioning, subsequently reduced freezing during fear extinction. Similarly, IL-HFS given immediately, but not three hours after, retrieval of a CTA memory reduced aversion during extinction. These data indicate that HFS of the IL may be an effective method for reducing both learned fear and learned aversion.

  5. Latent inhibition and facilitation of conditioned taste aversion in preweanling rats.

    Science.gov (United States)

    Gaztañaga, Mirari; Aranda-Fernández, P Ezequiel; Díaz-Cenzano, Elena; Chotro, M Gabriela

    2015-01-01

    Early in ontogeny, taste preexposure has been found to induce latent inhibition as well as produce a facilitation of conditioned taste aversion (CTA). In this study, the effect of taste preexposure on CTA was investigated in 13-14 day old rats as a function of taste preexposure (0, 1, or 3 trials) and unconditioned stimulus intensity (LiCl: 0, 0.15, or 0.30 M). After one conditioning trial, with the low intensity US, an aversion was only observed after taste preexposure (facilitation). When using the strong US, an aversion was found without preexposure while latent inhibition was observed with 3 preexposure trials. In conclusion, stimulus preexposure can either facilitate conditioning or produce latent inhibition in infant rats, depending on the amount of stimulus preexposure and the intensity of the US.

  6. 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.

  7. Serotonin 2A receptors contribute to the regulation of risk-averse decisions

    DEFF Research Database (Denmark)

    Macoveanu, Julian; Rowe, James B; Hornboll, Bettina

    2013-01-01

    -averse choice behavior was abolished by 5-HT2A receptor blockade. The results provide the first evidence for a critical role of 5-HT2A receptor function in regulating risk-averse behavior. We suggest that the 5-HT2A receptor system facilitates risk-taking behavior by modulating the outcome evaluation of "missed......Pharmacological studies point to a role of the neurotransmitter serotonin (5-HT) in regulating the preference for risky decisions, yet the functional contribution of specific 5-HT receptors remains to be clarified. We used pharmacological fMRI to investigate the role of the 5-HT2A receptors...... in processing negative outcomes and regulating risk-averse behavior. During fMRI, twenty healthy volunteers performed a gambling task under two conditions: with or without blocking the 5-HT2A receptors. The volunteers repeatedly chose between small, likely rewards and large, unlikely rewards. Choices were...

  8. The role of contingencies and “principles of behavioral variation” in pigeons' pecking

    OpenAIRE

    Fenner, Douglas

    1980-01-01

    Staddon and Simmelhag's proposal that behavior is produced by “principles of behavioral variation” instead of contingencies of reinforcement was tested in two experiments. In the first experiment pigeons were exposed to either a fixed-interval schedule of response-contingent reinforcement, an autoshaping schedule of stimulus-contingent reinforcement, or a fixed-time schedule of noncontingent reinforcement. Pigeons exposed to contingent reinforcement came to peck more rapidly than those expose...

  9. Selection of UPFC Suitable Locations for System Security Improvement Under Normal and Network Contingencies

    OpenAIRE

    Visakha, K; Thukaram, D; Jenkins, Lawrence; Khincha, HP

    2003-01-01

    Electric power systems are exposed to various contingencies. Network contingencies often contribute to overloading of network branches, unsatisfactory voltages and also leading to problems of stability/voltage collapse. To maintain security of the systems, it is desirable to estimate the effect of contingencies and plan suitable measures to improve system security/stability. This paper presents an approach for selection of UPFC suitable locations considering normal and network contingencies a...

  10. Diagnostic performance and costs of contingent screening models for trisomy 21 incorporating non-invasive prenatal testing.

    Science.gov (United States)

    Maxwell, Susannah; O'Leary, Peter; Dickinson, Jan E; Suthers, Graeme K

    2017-08-01

    Contingent screening for trisomy 21 using non-invasive prenatal testing has the potential to reduce invasive diagnostic testing and increase the detection of trisomy 21. To describe the diagnostic and economic performance of prenatal screening models for trisomy 21 that use non-invasive prenatal testing as a contingent screen across a range of combined first trimester screening risk cut-offs from a public health system perspective. Using a hypothetical cohort of 300 000 pregnancies, we modelled the outcomes of 25 contingent non-invasive prenatal testing screening models and compared these to conventional screening, offering women with a high-risk (1 > 300) combined first trimester screening result an invasive test. The 25 models used a range of risk cut-offs. High-risk women were offered invasive testing. Intermediate-risk women were offered non-invasive prenatal testing. We report the cost of each model, detection rate, costs per diagnosis, invasive tests per diagnosis and the number of fetal losses per diagnosis. The cost per prenatal diagnosis of trisomy 21 using the conventional model was $51 876 compared to the contingent models which varied from $49 309-66 686. The number of diagnoses and cost per diagnosis increased as the intermediate-risk threshold was lowered. Results were sensitive to trisomy 21 incidence, uptake of testing and cost of non-invasive prenatal testing. Contingent non-invasive prenatal testing models using more sensitive combined first trimester screening risk cut-offs than conventional screening improved the detection rate of trisomy 21, reduced procedure-related fetal loss and could potentially be provided at a lower cost per diagnosis than conventional screening. © 2017 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  11. 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.

  12. 48 CFR 403.405 - Misrepresentations or violations of the Covenant Against Contingent Fees.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Misrepresentations or... Contingent Fees 403.405 Misrepresentations or violations of the Covenant Against Contingent Fees. (a) A suspected misrepresentation or violation of the Covenant Against Contingent Fees shall be documented in...

  13. 48 CFR 803.405 - Misrepresentations or violations of the Covenant Against Contingent Fees.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Misrepresentations or... INTEREST Contingent Fees 803.405 Misrepresentations or violations of the Covenant Against Contingent Fees... influence, misrepresentation of a contingent fee arrangement, or any other violation of the Covenant Against...

  14. 48 CFR 1403.405 - Misrepresentation or violations of the Covenant Against Contingent Fees.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Misrepresentation or violations of the Covenant Against Contingent Fees. 1403.405 Section 1403.405 Federal Acquisition Regulations... Contingent Fees 1403.405 Misrepresentation or violations of the Covenant Against Contingent Fees. (a) In...

  15. 48 CFR 903.405 - Misrepresentations or violations of the Covenant Against Contingent Fees.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Misrepresentations or violations of the Covenant Against Contingent Fees. 903.405 Section 903.405 Federal Acquisition Regulations... Contingent Fees 903.405 Misrepresentations or violations of the Covenant Against Contingent Fees. (b) Each...

  16. 48 CFR 603.405 - Misrepresentations or violations of the Covenant Against Contingent Fees.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Misrepresentations or violations of the Covenant Against Contingent Fees. 603.405 Section 603.405 Federal Acquisition Regulations... Contingent Fees 603.405 Misrepresentations or violations of the Covenant Against Contingent Fees. (a) The...

  17. 48 CFR 1303.405 - Misrepresentations or violations of the covenant against contingent fees.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Misrepresentations or violations of the covenant against contingent fees. 1303.405 Section 1303.405 Federal Acquisition Regulations... Contingent Fees 1303.405 Misrepresentations or violations of the covenant against contingent fees. If the...

  18. 78 FR 73449 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List...

    Science.gov (United States)

    2013-12-06

    ... AGENCY 40 CFR Part 300 National Oil and Hazardous Substances Pollution Contingency Plan; National... National Oil and Hazardous Substances Pollution Contingency Plan (NCP). This partial deletion pertains to...-- NATIONAL OIL AND HAZARDOUS SUBSTANCES POLLUTION CONTINGENCY PLAN 0 1. The authority citation for part...

  19. A Review of the Use of Group Contingencies in Preschool Settings

    Science.gov (United States)

    Pokorski, Elizabeth A.; Barton, Erin E.; Ledford, Jennifer R.

    2017-01-01

    Individual contingency management systems have been used successfully to improve behaviors in school settings--including preschools--but often come with associated challenges in time and personnel management. Group contingencies, in the form of independent, interdependent, and dependent contingencies, have been used in preschools to address these…

  20. A Review of the Use of Group Contingencies in Preschool Settings

    Science.gov (United States)

    Pokorski, Elizabeth A.; Barton, Erin E.; Ledford, Jennifer R.

    2017-01-01

    Individual contingency management systems have been used successfully to improve behaviors in school settings--including preschools--but often come with associated challenges in time and personnel management. Group contingencies, in the form of independent, interdependent, and dependent contingencies, have been used in preschools to address these…