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1.
Proc Natl Acad Sci U S A ; 119(42): e2208681119, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36215461

RESUMO

Older adults are frequent targets and victims of financial fraud. They may be especially susceptible to revictimization because of age-related changes in both episodic memory and social motivation. Here we examined these factors in a context where adaptive social decision-making requires intact associative memory for previous social interactions. Older adults made more maladaptive episodic memory-guided social decisions but not only because of poorer associative memory. Older adults were biased toward remembering people as being fair, while young adults were biased toward remembering people as being unfair. Holding memory constant, older adults engaged more with people that were familiar (regardless of the nature of the previous interaction), whereas young adults were prone to avoiding others that they remembered as being unfair. Finally, older adults were more influenced by facial appearances, choosing to interact with social partners that looked more generous, even though those perceptions were inconsistent with prior experience.


Assuntos
Tomada de Decisões , Memória Episódica , Comportamento Social , Idoso , Envelhecimento , Humanos , Transtornos da Memória , Rememoração Mental , Motivação , Adulto Jovem
2.
J Econ Psychol ; 1032024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38799018

RESUMO

People tend to discount the value of future rewards as the delay to receiving them increases. This phenomenon, known as temporal discounting, may underlie many impulsive behaviors, such as drug abuse and overeating. Given the potential role of temporal discounting in maladaptive behaviors, many efforts have been made to find experimental manipulations that reduce temporal discounting. One class of manipulations that has held some promise involves recalling positive autobiographical memories prior to making intertemporal choices. Just as imagining positive future events has been shown to reduce temporal discounting, a few studies have shown that recalling positive past events reduces temporal discounting, especially if memory retrieval evokes positive affective states, such as gratitude and nostalgia. However, we failed to replicate these findings. Here we present an internal meta-analysis combining data from 14 studies (n = 758) that involved within-subjects positive memory recall-based manipulations. In each study, temporal discounting was assessed using a monetary intertemporal choice task. The average effect size was not significantly different from zero. This finding helps elucidate the neurocognitive mechanisms of temporal discounting; whereas engaging the episodic memory system to imagine future events might promote more patience, engaging the episodic memory system to imagine past events does not.

3.
Cogn Affect Behav Neurosci ; 23(3): 705-717, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37081224

RESUMO

People often quit waiting for delayed rewards when the exact timing of those rewards is uncertain. This behavior often has been attributed to self-control failure. Another possibility is that quitting is the result of a rational decision-making process in the face of uncertainty, based on the decision-maker's expectations about the possible arrival times of the awaited reward. There are forms of temporal expectations (e.g., heavy-tailed) under which the expected time remaining until a reward arrives actually increases as time elapses. In those cases, the rational strategy is to quit waiting when the expected reward is no longer worth the expected time remaining. To arbitrate between the "limited self-control" and "temporal expectations" accounts of persistence, we measured pupil diameter during a persistence task, as a physiological marker of surprise (phasic responses) and effort (pre-decision diameter). Phasic pupil responses were elevated in response to reward receipt. Critically, the extent to which pupils dilated following rewards depended on the delay: people showed larger pupillary surprise responses the more delayed the reward was. This result suggests that people expect the reward less the longer they wait for it-a form of temporal expectations under which limiting persistence is rational. Moreover, predecision pupil diameter before quit events was not associated with how long the participant had been waiting, but rather, depended on how atypical the quit decision was compared with the participant's usual behavior. These data provide physiological evidence for a temporal expectations account of persistence under temporal uncertainty.


Assuntos
Atenção , Motivação , Humanos , Incerteza , Recompensa , Fatores de Tempo , Tomada de Decisões/fisiologia
4.
Annu Rev Neurosci ; 37: 263-87, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24905597

RESUMO

Although the prevalent view of emotion and decision making is derived from the notion that there are dual systems of emotion and reason, a modulatory relationship more accurately reflects the current research in affective neuroscience and neuroeconomics. Studies show two potential mechanisms for affect's modulation of the computation of subjective value and decisions. Incidental affective states may carry over to the assessment of subjective value and the decision, and emotional reactions to the choice may be incorporated into the value calculation. In addition, this modulatory relationship is reciprocal: Changing emotion can change choices. This research suggests that the neural mechanisms mediating the relation between affect and choice vary depending on which affective component is engaged and which decision variables are assessed. We suggest that a detailed and nuanced understanding of emotion and decision making requires characterizing the multiple modulatory neural circuits underlying the different means by which emotion and affect can influence choices.


Assuntos
Tomada de Decisões/fisiologia , Emoções/fisiologia , Animais , Mapeamento Encefálico , Humanos , Modelos Neurológicos , Vias Neurais/fisiologia
5.
Psychol Med ; 49(2): 190-199, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30070191

RESUMO

The National Institute of Mental Health launched the Research Domain Criteria (RDoC) initiative to better understand dimensions of behavior and identify targets for treatment. Examining dimensions across psychiatric illnesses has proven challenging, as reliable behavioral paradigms that are known to engage specific neural circuits and translate across diagnostic populations are scarce. Delay discounting paradigms seem to be an exception: they are useful for understanding links between neural systems and behavior in healthy individuals, with potential for assessing how these mechanisms go awry in psychiatric illnesses. This article reviews relevant literature on delay discounting (or the rate at which the value of a reward decreases as the delay to receipt increases) in humans, including methods for examining it, its putative neural mechanisms, and its application in psychiatric research. There exist rigorous and reproducible paradigms to evaluate delay discounting, standard methods for calculating discount rate, and known neural systems probed by these paradigms. Abnormalities in discounting have been associated with psychopathology ranging from addiction (with steep discount rates indicating relative preference for immediate rewards) to anorexia nervosa (with shallow discount rates indicating preference for future rewards). The latest research suggests that delay discounting can be manipulated in the laboratory. Extensively studied in cognitive neuroscience, delay discounting assesses a dimension of behavior that is important for decision-making and is linked to neural substrates and to psychopathology. The question now is whether manipulating delay discounting can yield clinically significant changes in behavior that promote health. If so, then delay discounting could deliver on the RDoC promise.


Assuntos
Desvalorização pelo Atraso/fisiologia , Transtornos Mentais/diagnóstico , Transtornos Mentais/fisiopatologia , National Institute of Mental Health (U.S.) , Humanos , Estados Unidos
6.
Depress Anxiety ; 34(5): 463-470, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28009473

RESUMO

BACKGROUND: Temporal discounting refers to the tendency for rewards to lose value as the expected delay to receipt increases. Individuals with anorexia nervosa (AN) have been found to show reduced temporal discounting rates, indicating a greater preference for delayed rewards compared to healthy peers. Obsessive-compulsive disorder (OCD) and social anxiety disorder (SAD) commonly co-occur with AN, and anxiety has been related to development and prognosis of AN. We examined whether reduced temporal discounting is present across these potentially related disorders, and explored the relationship between temporal discounting and anxiety transdiagnostically. METHODS: One hundred ninety six individuals (75 healthy controls (HC); 50 OCD; 27 AN; 44 SAD) completed two temporal discounting tasks in which they chose between smaller-sooner and larger-later monetary rewards. Two measures of discounting-discount rate and discount factor-were compared between diagnostic groups, and associations with anxious traits were examined. RESULTS: Individuals with AN showed decreased temporal discounting compared to HC. OCD and SAD groups did not differ significantly from HC. Across the sample, anxiety was associated with decreased discounting; more anxious individuals showed a greater preference for delayed reward. CONCLUSIONS: We replicated the findings that individuals with AN show an increased preference for delayed reward relative to HC and that individuals with OCD do not differ from HC. We also showed that individuals with SAD do not differ from HC in discounting. Across this large sample, two measures of anxious temperament were associated with temporal discounting. These data raise new questions about the relationship between this dimensional trait and psychopathology.


Assuntos
Anorexia Nervosa/fisiopatologia , Desvalorização pelo Atraso/fisiologia , Transtorno Obsessivo-Compulsivo/fisiopatologia , Fobia Social/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
7.
J Neurosci ; 35(46): 15369-78, 2015 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-26586823

RESUMO

During value-based decision-making, individuals consider the various options and select the one that provides the maximum subjective value. Although the brain integrates abstract information to compute and compare these values, the only behavioral outcome is often the decision itself. However, if the options are visual stimuli, during deliberation the brain moves the eyes from one stimulus to the other. Previous work suggests that saccade vigor, i.e., peak velocity as a function of amplitude, is greater if reward is associated with the visual stimulus. This raises the possibility that vigor during the free viewing of options may be influenced by the valuation of each option. Here, humans chose between a small, immediate monetary reward and a larger but delayed reward. As the deliberation began, vigor was similar for the saccades made to the two options but diverged 0.5 s before decision time, becoming greater for the preferred option. This difference in vigor increased as a function of the difference in the subjective values that the participant assigned to the delayed and immediate options. After the decision was made, participants continued to gaze at the options, but with reduced vigor, making it possible to infer timing of the decision from the sudden drop in vigor. Therefore, the subjective value that the brain assigned to a stimulus during decision-making affected the motor system via the vigor with which the eyes moved toward that stimulus. SIGNIFICANCE STATEMENT: We find that, as individuals deliberate between two rewarding options and arrive at a decision, the vigor with which they make saccades to each option reflects a real-time evaluation of that option. With deliberation, saccade vigor diverges between the two options, becoming greater for the option that the individual will eventually choose. The results suggest a shared element between the network that assigns value to a stimulus during the process of decision-making and the network that controls vigor of movements toward that stimulus.


Assuntos
Tomada de Decisões/fisiologia , Recompensa , Movimentos Sacádicos/fisiologia , Adolescente , Adulto , Atenção/fisiologia , Feminino , Humanos , Comportamento Impulsivo , Masculino , Testes Neuropsicológicos , Estimulação Luminosa , Tempo de Reação/fisiologia , Adulto Jovem
8.
J Cogn Neurosci ; 28(2): 261-74, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26439265

RESUMO

Whereas positive feedback is both rewarding and informative, negative feedback can be construed as either punishing (because it is indicative of poor performance) or informative (because it may lead to goal attainment). In this neuroimaging experiment, we highlighted the informational value of negative feedback by intermixing trials with and without feedback. When performance feedback is expected, positive feedback triggers an increase in striatal activity, whereas negative feedback elicits a decrease in striatal activity. We predicted that, in contrast, when feedback receipt is unpredictable, the striatal response to negative feedback would increase. Participants performed a paired-associate learning task during fMRI scanning. In one condition ("blocked feedback"), the receipt of feedback was predictable--participants knew whether or not they would receive feedback for their responses. In another condition ("mixed feedback"), the receipt of feedback was unpredictable--on a random 50% of trials, participants received feedback, and they otherwise received no feedback. Negative feedback in the mixed feedback condition elicited more striatal activity than negative feedback in the blocked feedback condition. In contrast, feedback omission evoked more striatal activity when feedback delivery was expected, compared to when it was unpredictable. This pattern emerged from an increase in caudate activity in response to negative feedback in the mixed feedback condition and a decrease in ventral striatal activity in response to no feedback in this condition. These results suggest that, by emphasizing the informational value of negative feedback, an unpredictable feedback context alters the striatal response to negative feedback and to the omission of feedback.


Assuntos
Antecipação Psicológica/fisiologia , Aprendizagem por Associação/fisiologia , Retroalimentação Psicológica/fisiologia , Neostriado/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Reconhecimento Visual de Modelos/fisiologia , Adulto Jovem
10.
J Neurophysiol ; 113(1): 4-13, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25339705

RESUMO

For the consequences of our actions to guide behavior, the brain must represent different types of outcome-related information. For example, an outcome can be construed as negative because an expected reward was not delivered or because an outcome of low value was delivered. Thus behavioral consequences can differ in terms of the information they provide about outcome probability and value. We investigated the role of the striatum in processing probability-based and value-based negative feedback by training participants to associate cues with food rewards and then employing a selective satiety procedure to devalue one food outcome. Using functional magnetic resonance imaging, we examined brain activity related to receipt of expected rewards, receipt of devalued outcomes, omission of expected rewards, omission of devalued outcomes, and expected omissions of an outcome. Nucleus accumbens activation was greater for rewarding outcomes than devalued outcomes, but activity in this region did not correlate with the probability of reward receipt. Activation of the right caudate and putamen, however, was largest in response to rewarding outcomes relative to expected omissions of reward. The dorsal striatum (caudate and putamen) at the time of feedback also showed a parametric increase correlating with the trialwise probability of reward receipt. Our results suggest that the ventral striatum is sensitive to the motivational relevance, or subjective value, of the outcome, while the dorsal striatum codes for a more complex signal that incorporates reward probability. Value and probability information may be integrated in the dorsal striatum, to facilitate action planning and allocation of effort.


Assuntos
Corpo Estriado/fisiologia , Retroalimentação Psicológica/fisiologia , Probabilidade , Recompensa , Antecipação Psicológica/fisiologia , Mapeamento Encefálico , Sinais (Psicologia) , Feminino , Alimentos , Preferências Alimentares , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Adulto Jovem
12.
Cognition ; 237: 105468, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37148639

RESUMO

When deciding how long to keep waiting for delayed rewards that will arrive at an uncertain time, different distributions of possible reward times dictate different optimal strategies for maximizing reward. When reward timing distributions are heavy-tailed (e.g., waiting on hold) there is a point at which waiting is no longer advantageous because the opportunity cost of waiting is too high. Alternatively, when reward timing distributions have more predictable timing (e.g., uniform), it is advantageous to wait as long as necessary for the reward. Although people learn to approximate optimal strategies, little is known about how this learning occurs. One possibility is that people learn a general cognitive representation of the probability distribution that governs reward timing and then infer a strategy from that model of the environment. Another possibility is that they learn an action policy in a way that depends more narrowly on direct task experience, such that general knowledge of the reward timing distribution is insufficient for expressing the optimal strategy. Here, in a series of studies in which participants decided how long to persist for delayed rewards before quitting, we provided participants with information about the reward timing distribution in several ways. Whether the information was provided through counterfactual feedback (Study 1), previous exposure (Studies 2a and 2b), or description (Studies 3a and 3b), it did not obviate the need for direct, feedback-driven learning in a decision context. Therefore, learning when to quit waiting for delayed rewards might depend on task-specific experience, not solely on probabilistic reasoning.


Assuntos
Aprendizagem , Recompensa , Humanos , Probabilidade , Fatores de Tempo , Incerteza
13.
Neuropsychology ; 37(3): 284-300, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35786960

RESUMO

OBJECTIVE: Cross-national work on neurocognitive testing has been characterized by inconsistent findings, suggesting the need for improved harmonization. Here, we describe a prospective harmonization approach in an ongoing global collaborative study. METHOD: Visuospatial N-Back, Tower of London (ToL), Stop Signal task (SST), Risk Aversion (RA), and Intertemporal Choice (ITC) tasks were administered to 221 individuals from Brazil, India, the Netherlands, South Africa, and the USA. Prospective harmonization methods were employed to ensure procedural similarity of task implementation and processing of derived task measures across sites. Generalized linear models tested for between-site differences controlling for sex, age, education, and socioeconomic status (SES). Associations with these covariates were also examined and tested for differences by site with site-by-covariate interactions. RESULTS: The Netherlands site performed more accurately on N-Back and ToL than the other sites, except for the USA site on the N-Back. The Netherlands and the USA sites performed faster than the other three sites during the go events in the SST. Finally, the Netherlands site also exhibited a higher tolerance for delay discounting than other sites on the ITC, and the India site showed more risk aversion than other sites on the RA task. However, effect size differences across sites on the five tasks were generally small (i.e., partial eta-squared < 0.05) after dropping the Netherlands (on ToL, N-Back, ITC, and SST tasks) and India (on the RA task). Across tasks, regardless of site, the N-Back (sex, age, education, and SES), ToL (sex, age, and SES), SST (age), and ITC (SES) showed associations with covariates. CONCLUSIONS: Four out of the five sites showed only small between-site differences for each task. Nevertheless, despite our extensive prospective harmonization steps, task score performance deviated from the other sites in the Netherlands site (on four tasks) and the India site (on one task). Because the procedural methods were standardized across sites, and our analyses were adjusted for covariates, the differences found in cognitive performance may indicate selection sampling bias due to unmeasured confounders. Future studies should follow similar cross-site prospective harmonization procedures when assessing neurocognition and consider measuring other possible confounding variables for additional statistical control. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Classe Social , Humanos , Estudos Prospectivos , Estudos Longitudinais , Escolaridade , Testes Neuropsicológicos
14.
Philos Trans R Soc Lond B Biol Sci ; 377(1866): 20210338, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36314145

RESUMO

Intertemporal decision-making has long been assumed to measure self-control, with prominent theories treating choices of smaller, sooner rewards as failed attempts to override immediate temptation. If this view is correct, people should be more confident in their intertemporal decisions when they 'successfully' delay gratification than when they do not. In two pre-registered experiments with built-in replication, adult participants (n = 117) made monetary intertemporal choices and rated their confidence in having made the right decisions. Contrary to assumptions of the self-control account, confidence was not higher when participants chose delayed rewards. Rather, participants were more confident in their decisions when possible rewards were further apart in time-discounted subjective value, closer to the present, and larger in magnitude. Demonstrating metacognitive insight, participants were more confident in decisions that better aligned with their separate valuation of possible rewards. Decisions made with less confidence were more prone to changes-of-mind and more susceptible to a patience-enhancing manipulation. Together, our results establish that confidence in intertemporal choice tracks uncertainty in estimating and comparing the value of possible rewards-just as it does in decisions unrelated to self-control. Our findings challenge self-control views and instead cast intertemporal choice as a form of value-based decision-making about future possibilities. This article is part of the theme issue 'Thinking about possibilities: mechanisms, ontogeny, functions and phylogeny'.


Assuntos
Desvalorização pelo Atraso , Recompensa , Adulto , Humanos , Motivação , Julgamento , Previsões , Comportamento de Escolha
15.
Sci Rep ; 10(1): 6431, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286440

RESUMO

When making choices between smaller, sooner rewards and larger, later ones, people tend to discount future outcomes. Individual differences in temporal discounting in older adults have been associated with episodic memory abilities and entorhinal cortical thickness. The cause of this association between better memory and more future-oriented choice remains unclear, however. One possibility is that people with perceptually richer recollections are more patient because they also imagine the future more vividly. Alternatively, perhaps people whose memories focus more on the meaning of events (i.e., are more "gist-based") show reduced temporal discounting, since imagining the future depends on interactions between semantic and episodic memory. We examined which categories of episodic details - perception-based or gist-based - are associated with temporal discounting in older adults. Older adults whose autobiographical memories were richer in perception-based details showed reduced temporal discounting. Furthermore, in an exploratory neuroanatomical analysis, both discount rates and perception-based details correlated with entorhinal cortical thickness. Retrieving autobiographical memories before choice did not affect temporal discounting, however, suggesting that activating episodic memory circuitry at the time of choice is insufficient to alter discounting in older adults. These findings elucidate the role of episodic memory in decision making, which will inform interventions to nudge intertemporal choices.


Assuntos
Desvalorização pelo Atraso , Memória Episódica , Idoso , Idoso de 80 Anos ou mais , Comportamento de Escolha , Córtex Entorrinal/anatomia & histologia , Feminino , Humanos , Masculino , Rememoração Mental , Percepção/fisiologia , Análise e Desempenho de Tarefas , Lobo Temporal/anatomia & histologia
16.
Neuropsychologia ; 146: 107549, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32621907

RESUMO

When facing decisions involving trade-offs between smaller, sooner and larger, delayed rewards, people tend to discount the value of future rewards. There are substantial individual differences in this tendency toward temporal discounting, however. One neurocognitive system that may underlie these individual differences is episodic memory, given the overlap in the neural circuitry involved in imagining the future and remembering the past. Here we tested this hypothesis in older adults, including both those that were cognitively normal and those with amnestic mild cognitive impairment (MCI). We found that performance on neuropsychological measures of episodic memory retrieval was associated with temporal discounting, such that people with better memory discounted delayed rewards less. This relationship was specific to episodic memory and temporal discounting, since executive function (another cognitive ability) was unrelated to temporal discounting, and episodic memory was unrelated to risk tolerance (another decision-making preference). We also examined cortical thickness and volume in medial temporal lobe regions critical for episodic memory. Entorhinal cortical thickness was associated with reduced temporal discounting, with episodic memory performance partially mediating this association. The inclusion of MCI participants was critical to revealing these associations between episodic memory and entorhinal cortical thickness and temporal discounting. These effects were larger in the MCI group, reduced after controlling for MCI status, and statistically significant only when including MCI participants in analyses. Overall, these findings suggest that individual differences in temporal discounting are driven by episodic memory function, and that a decline in medial temporal lobe structural integrity may impact temporal discounting.


Assuntos
Desvalorização pelo Atraso/fisiologia , Memória Episódica , Idoso , Idoso de 80 Anos ou mais , Disfunção Cognitiva/fisiopatologia , Feminino , Humanos , Masculino , Rememoração Mental/fisiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Recompensa
17.
Nat Hum Behav ; 4(3): 317-325, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32015487

RESUMO

Understanding how people rate their confidence is critical for the characterization of a wide range of perceptual, memory, motor and cognitive processes. To enable the continued exploration of these processes, we created a large database of confidence studies spanning a broad set of paradigms, participant populations and fields of study. The data from each study are structured in a common, easy-to-use format that can be easily imported and analysed using multiple software packages. Each dataset is accompanied by an explanation regarding the nature of the collected data. At the time of publication, the Confidence Database (which is available at https://osf.io/s46pr/) contained 145 datasets with data from more than 8,700 participants and almost 4 million trials. The database will remain open for new submissions indefinitely and is expected to continue to grow. Here we show the usefulness of this large collection of datasets in four different analyses that provide precise estimations of several foundational confidence-related effects.


Assuntos
Bases de Dados Factuais/estatística & dados numéricos , Processos Mentais/fisiologia , Metacognição/fisiologia , Psicometria , Análise e Desempenho de Tarefas , Adulto , Comportamento de Escolha/fisiologia , Conjuntos de Dados como Assunto/estatística & dados numéricos , Humanos , Psicometria/instrumentação , Psicometria/estatística & dados numéricos , Tempo de Reação/fisiologia
18.
Front Behav Neurosci ; 12: 45, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29628878

RESUMO

Acute stress can harm performance. Paradoxically, writing about stressful events-such as past failures-has been shown to improve cognitive functioning and performance, especially in tasks that require sustained attention. Yet, there is little physiological evidence for whether writing about past failures or other negative events improves performance by reducing stress. In this experiment, we studied the effects of an acute psychosocial stressor, the Trier Social Stress Test, on attentional performance and salivary cortisol release in humans. Additionally, we investigated whether an expressive writing task could reduce the detrimental effects of stress, both on performance and physiological response. We found that when individuals were asked to write about a past failure before experiencing a stressor, they exhibited attenuated stress responses. Moreover, those who wrote about a past failure before being exposed to stress also exhibited better behavioral performance. Our results suggest that writing about a previous failure may allow an individual to experience a new stressor as less stressful, reducing its physiological and behavioral effects.

19.
Neurobiol Stress ; 8: 1-9, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29214188

RESUMO

People frequently fail to wait for delayed rewards after choosing them. These preference reversals are sometimes thought to reflect self-control failure. Other times, however, continuing to wait for a delayed reward may be counterproductive (e.g., when reward timing uncertainty is high). Research has demonstrated that people can calibrate how long to wait for rewards in a given environment. Thus, the role of self-control might be to integrate information about the environment to flexibly adapt behavior, not merely to promote waiting. Here we tested effects of acute stress, which has been shown to tax control processes, on persistence, and the calibration of persistence, in young adult human participants. Half the participants (n = 60) performed a task in which persistence was optimal, and the other half (n = 60) performed a task in which it was optimal to quit waiting for reward soon after each trial began. Each participant completed the task either after cold pressor stress or no stress. Stress did not influence persistence or optimal calibration of persistence. Nevertheless, an exploratory analysis revealed an "inverted-U" relationship between cortisol increase and performance in the stress groups, suggesting that choosing the adaptive waiting policy may be facilitated with some stress and impaired with severe stress.

20.
Soc Cogn Affect Neurosci ; 12(10): 1584-1593, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28655195

RESUMO

People generally prefer rewards sooner rather than later. This phenomenon, temporal discounting, underlies many societal problems, including addiction and obesity. One way to reduce temporal discounting is to imagine positive future experiences. Since there is overlap in the neural circuitry associated with imagining future experiences and remembering past events, here we investigate whether recalling positive memories can also promote more patient choice. We found that participants were more patient after retrieving positive autobiographical memories, but not when they recalled negative memories. Moreover, individuals were more impulsive after imagining novel positive scenes that were not related to their memories, showing that positive imagery alone does not drive this effect. Activity in the striatum and temporo parietal junction during memory retrieval predicted more patient choice, suggesting that to the extent that memory recall is rewarding and involves perspective-taking, it influences decision-making. Furthermore, representational similarity in the ventromedial prefrontal cortex between memory recall and decision phases correlated with the behavioral effect across participants. Thus, we have identified a novel manipulation for reducing temporal discounting-remembering the positive past-and have begun to characterize the psychological and neural mechanisms behind it.


Assuntos
Desvalorização pelo Atraso , Memória Episódica , Adulto , Mapeamento Encefálico , Tomada de Decisões , Feminino , Humanos , Imaginação , Comportamento Impulsivo , Imageamento por Ressonância Magnética , Masculino , Rememoração Mental/fisiologia , Neostriado/diagnóstico por imagem , Neostriado/fisiologia , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Adulto Jovem
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