Decisions under uncertainty: probabilistic context influences activation of prefrontal and parietal cortices

Motivational Modulation Enhances Movement Performance in Parkinson's Disease: A Systematic Review

Background

The assessment of motivation and its modulation during treatment are essential aspects of physical therapy practice. However, the modulation of motivation has been sparsely investigated in persons with Parkinson's disease (PD) and at present no studies have synthesized its effects on movement performance.

Objectives

4The purpose of this study was to systematically examine the efficacy of motivational modulation on movement performance in PD and to provide recommendations for its role in physical therapy practice.

Methods

Systematic identification of published literature was performed adhering to PRISMA guidelines, from January 2005 to March 2023. Keywords were used in the following electronic databases: PubMed, Academic Search Complete, the Cochrane Database, Google Scholar, and the Physiotherapy Evidence Database (PEDro). A level of evidence rating was completed according to the scale provided by the American Academy of Cerebral Palsy and Development Medicine. Quality assessments were performed using the Modified Downs and Black checklist.

Results

Eight studies were included in this review, all achieving level III evidence. The methodological quality of studies was varied, with most studies attaining a fair rating. Persons with PD performed upper extremity movement tasks with greater intensity when incentivized with larger rewards compared to smaller incentives. Dopamine replacement medication, Deep Brain Stimulation, and a history of depression, had mediating effects on the response to motivational modulation.

Conclusions

Our findings suggest that it is plausible to improve adherence to exercise when physical therapists modulate motivation through computerized game achievements, gamification of tasks, or other forms of reward and non-rewarding stimuli.

Dynamic changes in task preparation in a multi-task environment: The task transformation paradigm

A key element of human flexible behavior concerns the ability to continuously predict and prepare for sudden changes in tasks or actions. Here, we tested whether people can dynamically modulate task preparation processes and decision-making strategies when the identity of a to-be-performed task becomes uncertain. To this end, we developed a new paradigm where participants need to prepare for one of nine tasks on each trial. Crucially, in some blocks, the task being prepared could suddenly shift to a different task after a longer cue-target interval, by changing either the stimulus category or categorization rule that defined the initial task. We found that participants were able to dynamically modulate task preparation in the face of this task uncertainty. A second experiment shows that these changes in behavior were not simply a function of decreasing task expectancy, but rather of increasing switch expectancy. Finally, in the third and fourth experiment, we demonstrate that these dynamic modulations can be applied in a compositional manner, depending on whether either only the stimulus category or categorization rule would be expected to change.

Mapping the Neural Basis of Neuroeconomics with Functional Magnetic Resonance Imaging: A Narrative Literature Review

Neuroeconomics merges neuroscience, economics, and psychology to investigate the neural basis of decision making. Decision making involves assessing outcomes with subjective value, shaped by emotions and experiences, which are crucial in economic decisions. Functional MRI (fMRI) reveals key areas of the brain, including the ventro-medial prefrontal cortex, that are involved in subjective value representation. Collaborative interdisciplinary efforts are essential for advancing the field of neuroeconomics, with implications for clinical interventions and policy design. This review explores subjective value in neuroeconomics, highlighting brain regions identified through fMRI studies.

Functional brain networks in Developmental Topographical Disorientation

Despite a decade-long study on Developmental Topographical Disorientation, the underlying mechanism behind this neurological condition remains unknown. This lifelong selective inability in orientation, which causes these individuals to get lost even in familiar surroundings, is present in the absence of any other neurological disorder or acquired brain damage. Herein, we report an analysis of the functional brain network of individuals with Developmental Topographical Disorientation ($n = 19$) compared against that of healthy controls ($n = 21$), all of whom underwent resting-state functional magnetic resonance imaging, to identify if and how their underlying functional brain network is altered. While the established resting-state networks (RSNs) are confirmed in both groups, there is, on average, a greater connectivity and connectivity strength, in addition to increased global and local efficiency in the overall functional network of the Developmental Topographical Disorientation group. In particular, there is an enhanced connectivity between some RSNs facilitated through indirect functional paths. We identify a handful of nodes that encode part of these differences. Overall, our findings provide strong evidence that the brain networks of individuals suffering from Developmental Topographical Disorientation are modified by compensatory mechanisms, which might open the door for new diagnostic tools.

Posterior parietal cortex is causally involved in reward valuation but not in probability weighting during risky choice

This study provides evidence that the posterior parietal cortex is causally involved in risky decision making via the processing of reward values but not reward probabilities. In the within-group experimental design, participants performed a binary lottery choice task following transcranial magnetic stimulation of the right posterior parietal cortex, left posterior parietal cortex, and a right posterior parietal cortex sham (placebo) stimulation. The continuous theta-burst stimulation protocol supposedly downregulating the cortical excitability was used. Both, mean-variance and the prospect theory approach to risky choice showed that the posterior parietal cortex stimulation shifted participants toward greater risk aversion compared with sham. On the behavioral level, after the posterior parietal cortex stimulation, the likelihood of choosing a safer option became more sensitive to the difference in standard deviations between lotteries, compared with sham, indicating greater risk avoidance within the mean-variance framework. We also estimated the shift in prospect theory parameters of risk preferences after posterior parietal cortex stimulation. The hierarchical Bayesian approach showed moderate evidence for a credible change in risk aversion parameter toward lower marginal reward value (and, hence, lower risk tolerance), while no credible change in probability weighting was observed. In addition, we observed anecdotal evidence for a credible increase in the consistency of responses after the left posterior parietal cortex stimulation compared with sham.

The parietal cortex has a causal role in ambiguity computations in humans

Humans often face the challenge of making decisions between ambiguous options. The level of ambiguity in decision-making has been linked to activity in the parietal cortex, but its exact computational role remains elusive. To test the hypothesis that the parietal cortex plays a causal role in computing ambiguous probabilities, we conducted consecutive fMRI and TMS-EEG studies. We found that participants assigned unknown probabilities to objective probabilities, elevating the uncertainty of their decisions. Parietal cortex activity correlated with the objective degree of ambiguity and with a process that underestimates the uncertainty during decision-making. Conversely, the midcingulate cortex (MCC) encodes prediction errors and increases its connectivity with the parietal cortex during outcome processing. Disruption of the parietal activity increased the uncertainty evaluation of the options, decreasing cingulate cortex oscillations during outcome evaluation and lateral frontal oscillations related to value ambiguous probability. These results provide evidence for a causal role of the parietal cortex in computing uncertainty during ambiguous decisions made by humans.

Distributed attribute representation in the superior parietal lobe during probabilistic decision-making

Several studies have examined the neural substrates of probabilistic decision-making, but few have systematically investigated the neural representations of the two objective attributes of probabilistic rewards, that is, the reward amount and the probability. Specifically, whether there are common or distinct neural activity patterns to represent the objective attributes and their association with the neural representation of the subjective valuation remains largely underexplored. We conducted two studies (nStudy1  = 34, nStudy2  = 41) to uncover distributed neural representations of the objective attributes and subjective value as well as their association with individual probability discounting rates. The amount and probability were independently manipulated to better capture brain signals sensitive to these two attributes and were presented simultaneously in Study 1 and successively in Study 2. Both univariate and multivariate pattern analyses showed that the brain activities in the superior parietal lobule (SPL), including the postcentral gyrus, were modulated by the amount of rewards and probability in both studies. Further, representational similarity analysis revealed a similar neural representation between these two objective attributes and between the attribute and valuation. Moreover, the SPL tracked the subjective value integrated by the hyperbolic function. Probability-related brain activations in the inferior parietal lobule were associated with the variability in individual discounting rates. These findings provide novel insights into a similar neural representation of the two attributes during probabilistic decision-making and perhaps support the common neural coding of stimulus objective properties and subjective value in the field of probabilistic discounting.

Studying the neural representations of uncertainty

The study of the brain's representations of uncertainty is a central topic in neuroscience. Unlike most quantities of which the neural representation is studied, uncertainty is a property of an observer's beliefs about the world, which poses specific methodological challenges. We analyze how the literature on the neural representations of uncertainty addresses those challenges and distinguish between 'code-driven' and 'correlational' approaches. Code-driven approaches make assumptions about the neural code for representing world states and the associated uncertainty. By contrast, correlational approaches search for relationships between uncertainty and neural activity without constraints on the neural representation of the world state that this uncertainty accompanies. To compare these two approaches, we apply several criteria for neural representations: sensitivity, specificity, invariance and functionality. Our analysis reveals that the two approaches lead to different but complementary findings, shaping new research questions and guiding future experiments.

Critical tests of fuzzy trace theory in brain and behavior: uncertainty across time, probability, and development

Uncertainty permeates decisions from the trivial to the profound. Integrating brain and behavioral evidence, we discuss how probabilistic (varied outcomes) and temporal (delayed outcomes) uncertainty differ across age and individuals; how critical tests adjudicate between theories of uncertainty (prospect theory and fuzzy-trace theory); and how these mechanisms might be represented in the brain. The same categorical gist representations of gains and losses account for choices and eye-tracking data in both value-allocation (add money to gambles) and risky-choice tasks, disconfirming prospect theory and confirming predictions of fuzzy-trace theory. The analysis is extended to delay discounting and disambiguated choices, explaining hidden-zero effects that similarly turn on categorical distinctions between some gain and no gain, certain gain and uncertain gain, gain and loss, and now and later. Bold activation implicates dorsolateral prefrontal and posterior parietal cortices in gist strategies that are not just one tool in a grab-bag of cognitive options but rather are general strategies that systematically predict behaviors across many different tasks involving probabilistic and temporal uncertainty. High valuation (e.g., ventral striatum; ventromedial prefrontal cortex) and low executive control (e.g., lateral prefrontal cortex) contribute to risky and impatient choices, especially in youth. However, valuation in ventral striatum supports reward-maximizing and gist strategies in adulthood. Indeed, processing becomes less "rational" in the sense of maximizing gains and more noncompensatory (eye movements indicate fewer tradeoffs) as development progresses from adolescence to adulthood, as predicted. Implications for theoretically predicted "public-health paradoxes" are discussed, including gist versus verbatim thinking in drug experimentation and addiction.

Insular and Striatal Correlates of Uncertain Risky Reward Pursuit in Schizophrenia

BACKGROUND AND HYPOTHESIS

Risk-taking in specific contexts can be beneficial, leading to rewarding outcomes. Schizophrenia is associated with disadvantageous decision-making, as subjects pursue uncertain risky rewards less than controls. However, it is unclear whether this behavior is associated with more risk sensitivity or less reward incentivization. Matching on demographics and intelligence quotient (IQ), we determined whether risk-taking was more associated with brain activation in regions affiliated with risk evaluation or reward processing.

STUDY DESIGN

Subjects (30 schizophrenia/schizoaffective disorder, 30 controls) completed a modified, fMRI Balloon Analogue Risk Task. Brain activation was modeled during decisions to pursue risky rewards and parametrically modeled according to risk level.

STUDY RESULTS

The schizophrenia group exhibited less risky-reward pursuit despite previous adverse outcomes (Average Explosions; F(1,59) = 4.06, P = .048) but the comparable point at which risk-taking was volitionally discontinued (Adjusted Pumps; F(1,59) = 2.65, P = .11). Less activation was found in schizophrenia via whole brain and region of interest (ROI) analyses in the right (F(1,59) = 14.91, P < 0.001) and left (F(1,59) = 16.34, P < 0.001) nucleus accumbens (NAcc) during decisions to pursue rewards relative to riskiness. Risk-taking correlated with IQ in schizophrenia, but not controls. Path analyses of average ROI activation revealed less statistically determined influence of anterior insula upon dorsal anterior cingulate bilaterally (left: χ2 = 12.73, P < .001; right: χ2 = 9.54, P = .002) during risky reward pursuit in schizophrenia.

CONCLUSIONS

NAcc activation in schizophrenia varied less according to the relative riskiness of uncertain rewards compared to controls, suggesting aberrations in reward processing. The lack of activation differences in other regions suggests similar risk evaluation. Less insular influence on the anterior cingulate may relate to attenuated salience attribution or inability for risk-related brain region collaboration to sufficiently perceive situational risk.

Gambling on an empty stomach: Hunger modulates preferences for learned but not described risks

INTRODUCTION

We assess risks differently when they are explicitly described, compared to when we learn directly from experience, suggesting dissociable decision-making systems. Our needs, such as hunger, could globally affect our risk preferences, but do they affect described and learned risks equally? On one hand, decision-making from descriptions is often considered flexible and context sensitive, and might therefore be modulated by metabolic needs. On the other hand, preferences learned through reinforcement might be more strongly coupled to biological drives.

METHOD

Thirty-two healthy participants (females: 20, mean age: 25.6 ± 6.5 years) with a normal weight (Body Mass Index: 22.9 ± 3.2 kg/m2 ) were tested in a within-subjects counterbalanced, randomized crossover design for the effects of hunger on two separate risk-taking tasks. We asked participants to choose between two options with different risks to obtain monetary outcomes. In one task, the outcome probabilities were described numerically, whereas in a second task, they were learned.

RESULT

In agreement with previous studies, we found that rewarding contexts induced risk-aversion when risks were explicitly described (F1,31  = 55.01, p < .0001, ηp 2  = .64), but risk-seeking when they were learned through experience (F1,31  = 10.28, p < .003, ηp 2  = .25). Crucially, hunger attenuated these contextual biases, but only for learned risks (F1,31  = 8.38, p < .007, ηp 2  = .21).

CONCLUSION

The results suggest that our metabolic state determines risk-taking biases when we lack explicit descriptions.

A Role for Uncertainty in the Neural Distinction Between Social and Nonsocial Thought

Neuroimaging research has identified a network of brain regions that is consistently more engaged when people think about the minds of other people than when they engage in nonsocial tasks. Activations in this "mentalizing network" are sometimes interpreted as evidence for the domain-specificity of cognitive processes supporting social thought. Here, we examine the alternative possibility that at least some activations in the mentalizing network may be explained by uncertainty. A reconsideration of findings from existing functional MRI studies in light of new data from independent raters suggests that (a) social tasks used in past studies have higher levels of uncertainty than their nonsocial comparison tasks and (b) activation in a key brain region associated with social cognition, the dorsomedial prefrontal cortex (DMPFC), may track with the degree of uncertainty surrounding both social and nonsocial inferences. These observations suggest that the preferential DMPFC response observed consistently in social scenarios may reflect the engagement of domain-general processes of uncertainty reduction, which points to avenues for future research into the core cognitive mechanisms supporting typical and atypical social thought.

Conceptualisation of Uncertainty in Decision Neuroscience Research: Do We Really Know What Types of Uncertainties The Measured Neural Correlates Relate To?

In the article "What are neural correlates neural correlates of?" published in the journal BioSocieties, Gabriel Abend points out that neuroscientists cannot avoid philosophical questions concerning the conceptualization and operationalization of social-psychological phenomena they deal with at the physiological level. In this article, we build on Abend's thesis and, through a systematic literature review of decision neuroscience studies, test it with the example of the social-psychological phenomenon of uncertainty in decision making. In this paper, we provide an overview of studies that appropriately attempt to conceptualise uncertainty, and then use these studies to analyse papers looking for neural correlates of uncertainty. Based on a systematic review of studies, we investigate what types of uncertainty authors in the field of decision neuroscience address and define, what criteria they use to distinguish between these types, what problems are associated with their conceptualization, and whether the neural correlates of different types of uncertainty can be accurately identified. The paper concludes that, particularly in the economic context, a collaboration between the natural and social sciences works well, and neuroscience studies use economic conceptualizations of uncertainty that are further developed by sophisticated decision tasks. However, the paper also highlights problematic aspects that obscure the understanding of the phenomena under study. These include the lack of criteria for distinguishing between different types of phenomena, the unclear use of the general concept of uncertainty, and the confusion of phenomena or their erroneous synonymous use.

A new Bayesian procedure for the estimation of the referees' decision thresholds and agreement. The case of professional handball refereeing

In double refereeing, agreement between referees is fundamental for the achievement of a flawless and smooth refereeing activity. Nonetheless, the agreeement can be affected by several external and internal factors, with a negative impact on the consistency of the refereeing and the fluidity of the game. The referee's Decision Threshold (DT) is the limit above which the evidence of a foul results in the call of an infraction by the referee. It represents the individual refereeing style, and it is one of the factors that can contribute to low agreement between the referees. We present an application of a new Bayesian procedure to estimate referee's DT in a typical refereeing task. To this end, 56 italian professional handball (FIGH) referees were asked to evaluate 96 potential foul plays, belonging to four different infraction types: 7-m throw, passive play, offensive foul, disciplinary sanctions. The proposed method provides information about: (i) referee's individual DT; (ii) the agreement between pairs of referees (i.e., one-to-one); (iii) the agreement between each referee and all the other referees (i.e., one-to-total); (iv) the agreement between each referee and a reference referee (i.e., one-to-expert); (v) the proportion of agreement between the referees and a reference referee for each potential foul play. Sport federations would profit by this procedure in different ways: by using the information about the DT to train referees, by detecting referees with a low agreement with their colleagues or with the reference referee, by focusing training on specific plays to improve the arbitration class internal consistency.

The Effect of Spatial Uncertainty on Visual Search in Older School-Aged Children with and without ADHD

OBJECTIVE

Numerous studies support that simple visual search tests may not be sufficient to differentiate children with and without attention-deficit/hyperactivity disorder (ADHD), especially for older school-aged children. This study aimed to explore whether the high spatial uncertainty visual search tasks can effectively discriminate older school-aged children with ADHD from their typically developing (TD) peers.

METHOD

In a randomized, two-period crossover design, 122 school-aged children (61 ADHD and 61 TD subjects), aged 10-12 years old, were measured using comparable visual search tasks with structured and unstructured layouts.

RESULTS

First, the discriminant effectiveness of unstructured visual search tasks, which are associated with high-level spatial uncertainty, is superior to structured ones. Second, combining accuracy and speed into a Q score is a more sensitive measure than accuracy or time calculated alone in visual search tasks. A more in-depth ROC analysis showed that all variables could accurately identify ADHD from their TD peers under unstructured visual search tasks, with the index of the Q score performing best (AUR = 0.956). Third, the development of detectability, which represents the ability to distinguish between target and non-target, is approaching maturity in 10-12-year-old children with ADHD. However, these children showed severe deficits in dealing with disorganized distractors when performing visual search tasks with high-level spatial uncertainty.

CONCLUSIONS

The findings of this study support that older school-aged children with ADHD demonstrate less efficient search performance than their TD peers in complex/difficult visual search tasks, especially under higher spatial uncertainty.

Effects of baclofen on insular gain anticipation in alcohol-dependent patients - a randomized, placebo-controlled, pharmaco-fMRI pilot trial

RATIONALE

One hallmark of addiction is an altered neuronal reward processing. In healthy individuals (HC), reduced activity in fronto-striatal regions including the insula has been observed when a reward anticipation task was performed repeatedly. This effect could indicate a desensitization of the neural reward system due to repetition. Here, we investigated this hypothesis in a cohort of patients with alcohol use disorder (AUD), who have been treated with baclofen or a placebo. The efficacy of baclofen in AUD patients has been shown to have positive clinical effects, possibly via indirectly affecting structures within the neuronal reward system.

OBJECTIVES

Twenty-eight recently detoxified patients (13 receiving baclofen (BAC), 15 receiving placebo (PLA)) were investigated within a longitudinal, double-blind, and randomized pharmaco-fMRI design with an individually adjusted daily dosage of 30-270 mg.

METHODS

Brain responses were captured by functional magnetic resonance imaging (fMRI) during reward anticipation while participating in a slot machine paradigm before (t1) and after 2 weeks of individual high-dose medication (t2).

RESULTS

Abstinence rates were significantly higher in the BAC compared to the PLA group during the 12-week high-dose medication phase. At t1, all patients showed significant bilateral striatal activation. At t2, the BAC group showed a significant decrease in insular activation compared to the PLA group.

CONCLUSIONS

By affecting insular information processing, baclofen might enable a more flexible neuronal adaptation during recurrent reward anticipation, which could resemble a desensitization as previously observed in HC. This result strengthens the modulation of the reward system as a potential mechanism of action of baclofen.

TRIAL REGISTRATION

Identifier of the main trial (the BACLAD study) at clinical.gov: NCT0126665.

Sex-related differences in violence exposure, neural reactivity to threat, and mental health

The prefrontal cortex (PFC), hippocampus, and amygdala play an important role in emotional health. However, adverse life events (e.g., violence exposure) affect the function of these brain regions, which may lead to disorders such as depression and anxiety. Depression and anxiety disproportionately affect women compared to men, and this disparity may reflect sex differences in the neural processes that underlie emotion expression and regulation. The present study investigated sex differences in the relationship between violence exposure and the neural processes that underlie emotion regulation. In the present study, 200 participants completed a Pavlovian fear conditioning procedure in which cued and non-cued threats (i.e., unconditioned stimuli) were presented during functional magnetic resonance imaging. Violence exposure was previously assessed at four separate time points when participants were 11-19 years of age. Significant threat type (cued versus non-cued) × sex and sex × violence exposure interactions were observed. Specifically, women and men differed in amygdala and parahippocampal gyrus reactivity to cued versus non-cued threat. Further, dorsolateral PFC (dlPFC) and inferior parietal lobule (IPL) reactivity to threat varied positively with violence exposure among women, but not men. Similarly, threat-elicited skin conductance responses varied positively with violence exposure among women. Finally, women reported greater depression and anxiety symptoms than men. These findings suggest that sex differences in threat-related brain and psychophysiological activity may have implications for mental health.

Neural Mechanisms and Psychology of Psychedelic Ego Dissolution

Neuroimaging studies of psychedelics have advanced our understanding of hierarchical brain organization and the mechanisms underlying their subjective and therapeutic effects. The primary mechanism of action of classic psychedelics is binding to serotonergic 5-HT2A receptors. Agonist activity at these receptors leads to neuromodulatory changes in synaptic efficacy that can have a profound effect on hierarchical message-passing in the brain. Here, we review the cognitive and neuroimaging evidence for the effects of psychedelics: in particular, their influence on selfhood and subject-object boundaries-known as ego dissolution-surmised to underwrite their subjective and therapeutic effects. Agonism of 5-HT2A receptors, located at the apex of the cortical hierarchy, may have a particularly powerful effect on sentience and consciousness. These effects can endure well after the pharmacological half-life, suggesting that psychedelics may have effects on neural plasticity that may play a role in their therapeutic efficacy. Psychologically, this may be accompanied by a disarming of ego resistance that increases the repertoire of perceptual hypotheses and affords alternate pathways for thought and behavior, including those that undergird selfhood. We consider the interaction between serotonergic neuromodulation and sentience through the lens of hierarchical predictive coding, which speaks to the value of psychedelics in understanding how we make sense of the world and specific predictions about effective connectivity in cortical hierarchies that can be tested using functional neuroimaging. SIGNIFICANCE STATEMENT: Classic psychedelics bind to serotonergic 5-HT2A receptors. Their agonist activity at these receptors leads to neuromodulatory changes in synaptic efficacy, resulting in a profound effect on information processing in the brain. Here, we synthesize an abundance of brain imaging research with pharmacological and psychological interpretations informed by the framework of predictive coding. Moreover, predictive coding is suggested to offer more sophisticated interpretations of neuroimaging findings by bridging the role between the 5-HT2A receptors and large-scale brain networks.

Common and Distinct Neural Correlates of Intertemporal and Risky Decision-Making: Meta-Analytical Evidence for the Dual-System Theory

The relationship between intertemporal and risky decision-making has received considerable attention in decision research. Single-process theories suggest that choices involving delay and risk are simply two manifestations of the same psychological mechanism, which implies similar patterns of neural activation. Conversely, the dual-system theory suggests that delayed and risky choices are two contrasting types of processes, which implies distinct brain networks. How these two types of choices relate to each other remains unclear. The current study addressed this issue by performing a meta-analysis of 28 intertemporal decision-making studies (862 subjects) and 51 risky decision-making studies (1539 subjects). We found no common area activated in the conjunction analysis of the delayed and risky rewards. Based on the contrast analysis, delayed rewards were associated with stronger activation in the left dorsal insula, while risky rewards were associated with activation in the bilateral ventral striatum and the right anterior insula. The results align with the dual-system theory with separate neural networks for delayed and risky rewards.

A Neuroeconomics Approach to Obesity

Obesity is a heterogeneous condition that is affected by physiological, behavioral, and environmental factors. Value-based decision making is a useful framework for integrating these factors at the individual level. The disciplines of behavioral economics and reinforcement learning provide tools for identifying specific cognitive and motivational processes that may contribute to the development and maintenance of obesity. Neuroeconomics complements these disciplines by studying the neural mechanisms underlying these processes. We surveyed recent literature on individual decision characteristics that are most frequently implicated in obesity: discounting the value of future outcomes, attitudes toward uncertainty, and learning from rewards and punishments. Our survey highlighted both consistent and inconsistent behavioral findings. These findings underscore the need to examine multiple processes within individuals to identify unique behavioral profiles associated with obesity. Such individual characterization will inform future studies on the neurobiology of obesity as well as the design of effective interventions that are individually tailored.

Beyond lottery-evoked ambiguity aversion: the neural signature of the types and the sources of uncertainty

Studies on decision-making under uncertainty have mainly focused on understanding preferences for either risk or ambiguity using standard lottery designs. However, people often face uncertainty that directly stems from interacting with other people, which may be processed differently from lottery-based uncertainty. Here, we substantially extend the investigation of uncertainty by examining a fourfold pattern of the sources and the types of uncertainty, assessing behavioral and neural responses to both risk and ambiguity across both social and non-social contexts. A key element in our research design was to control for participants' naturally occurring social beliefs, and taking these a priori beliefs into account allow us to elicit individual preferences in accordance with economic approaches that stress the dynamics of ambiguity preference as a function of underlying likelihoods. Using this design, we find a behavioral main effect of ambiguity aversion, with increasing ambiguity aversion as a function of higher beliefs regarding the likelihood of reciprocity, and related neural activity in the right IPS. This brain region was primarily involved when participants experienced lottery-based uncertainty as opposed to social uncertainty. However, we found that the right IFG was more involved when participants made decisions under social, as compared to non-social, uncertainty. Overall, therefore, the IPS may activate an analytic mindset, which might resonate more with a lottery than a social context, whereas the IFG is engaged when the context requires players to resolve uncertainty, such as unravelling the intentions behind the choice of another person.

Neuromonitoring Correlates of Expertise Level in Surgical Performers: A Systematic Review

Surgical expertise does not have a clear definition and is often culturally associated with power, authority, prestige, and case number rather than more objective proxies of excellence. Multiple models of expertise progression have been proposed including the Dreyfus model, however, they all currently require subjective evaluation of skill. Recently, efforts have been made to improve the ways in which surgical excellence is measured and expertise is defined using artificial intelligence, video recordings, and accelerometers. However, these aforementioned methods of assessment are still subjective or indirect proxies of expertise, thus uncovering the neural mechanisms that differentiate expert surgeons from trainees may enhance the objectivity of surgical expertise validation. In fact, some researchers have already suggested that their neural imaging-based expertise classification methods outperform currently used methods of surgical skill certification such as the Fundamentals of Laparoscopic Surgery (FLS) scores. Such imaging biomarkers would not only help better identify the highest performing surgeons, but could also improve residency programs by providing more objective, evidence-based feedback and developmental milestones for those in training and perhaps act as a marker of surgical potential in medical students. Despite the potential advantages of using neural imaging in the assessment of surgical expertise, this field of research remains in its infancy. This systematic review identifies studies that have applied neuromonitoring in assessing surgical skill across levels of expertise. The goals of this review are to identify (1) the strongest neural indicators of surgical expertise, (2) the limitations of the current literature on this subject, (3) the most sensible future directions for further study. We found substantial evidence that surgical expertise can be delineated by differential activation and connectivity in the prefrontal cortex (PFC) across multiple task and neuroimaging modalities. Specifically, novices tend to have greater PFC activation than experts under standard conditions in bimanual and decision-making tasks. However, under high temporal demand tasks, experts had increased PFC activation whereas novices had decreased PFC activation. Common limitations uncovered in this review were that task difficulty was often insufficient to delineate between residents and attending. Moreover, attending level involvement was also low in multiple studies which may also have contributed to this issue. Most studies did not analyze the ability of their neuromonitoring findings to accurately classify subjects by level of expertise. Finally, the predominance of fNIRS as the neuromonitoring modality limits our ability to uncover the neural correlates of surgical expertise in non-cortical brain regions. Future studies should first strive to address these limitations. In the longer term, longitudinal within-subjects design over the course of a residency or even a career will also advance the field. Although logistically arduous, such studies would likely be most beneficial in demonstrating effects of increasing surgical expertise on regional brain activation and inter-region connectivity.

People with jumping to conclusions bias tend to make context-independent decisions rather than context-dependent decisions

Beads task (BT) uses a probabilistic reasoning paradigm and reveals jumping to conclusions (JTC) bias, the tendency to make premature judgments based on insufficient information (i.e., making fewer draws to decision-DTD). In this study, healthy participants (N = 207) were tested on the 80:20 and 60:40 color ratio versions of BT. We investigated associations of JTC bias with a set of cognitive bias problems and Cognitive Bias Task (CBT), a non-veridical (agent-centered) decision-making task that determines context-dependent and context-independent decision-making bias.Results showed that the converted CBT scores were negatively, and cognitive bias scores were positively correlated with JTC bias (DTD ≤ 2) on both versions of the BT. The CBT demonstrated to have satisfactory convergent and predictive validity for JTC bias. The findings suggest that people with JTC bias fail to solve cognitive bias problems and are more likely to make context-independent response selections than context-dependent response selections.

Schizophrenia Patients Show Largely Similar Salience Signaling Compared to Healthy Controls in an Observational Task Environment

Recent evidence suggests that the aberrant signaling of salience is associated with psychotic illness. Salience, however, can take many forms in task environments. For example, salience may refer to any of the following: (1) the valence of an outcome, (2) outcomes that are unexpected, called reward prediction errors (PEs), or (3) cues associated with uncertain outcomes. Here, we measure brain responses to different forms of salience in the context of a passive PE-signaling task, testing whether patients with schizophrenia (SZ) showed aberrant signaling of particular types of salience. We acquired event-related MRI data from 29 SZ patients and 23 controls during the performance of a passive outcome prediction task. Across groups, we found that the anterior insula and posterior parietal cortices were activated to multiple different types of salience, including PE magnitude and heightened levels of uncertainty. However, BOLD activation to salient events was not significantly different between patients and controls in many regions, including the insula, posterior parietal cortices, and default mode network nodes. Such results suggest that deficiencies in salience processing in SZ may not result from an impaired ability to signal salience per se, but instead the ability to use such signals to guide future actions. Notably, no between-group differences were observed in BOLD signal changes associated with PE-signaling in the striatum. However, positive symptom severity was found to significantly correlate with the magnitudes of salience contrasts in default mode network nodes. Our results suggest that, in an observational environment, SZ patients may show an intact ability to activate striatal and cortical regions to rewarding and non-rewarding salient events. Furthermore, reduced deactivation of a hypothesized default mode network node for SZ participants with high levels of positive symptoms, following salient events, point to abnormalities in interactions of the salience network with other brain networks, and their potential importance to positive symptoms.

Functional Segregation within the Dorsal Frontoparietal Network: A Multimodal Dynamic Causal Modeling Study

Discrimination and integration of motion direction requires the interplay of multiple brain areas. Theoretical accounts of perception suggest that stimulus-related (i.e., exogenous) and decision-related (i.e., endogenous) factors affect distributed neuronal processing at different levels of the visual hierarchy. To test these predictions, we measured brain activity of healthy participants during a motion discrimination task, using electroencephalography (EEG) and functional magnetic resonance imaging (fMRI). We independently modeled the impact of exogenous factors (task demand) and endogenous factors (perceptual decision-making) on the activity of the motion discrimination network and applied Dynamic Causal Modeling (DCM) to both modalities. DCM for event-related potentials (DCM-ERP) revealed that task demand impacted the reciprocal connections between the primary visual cortex (V1) and medial temporal areas (V5). With practice, higher visual areas were increasingly involved, as revealed by DCM-fMRI. Perceptual decision-making modulated higher levels (e.g., V5-to-Frontal Eye Fields, FEF), in a manner predictive of performance. Our data suggest that lower levels of the visual network support early, feature-based selection of responses, especially when learning strategies have not been implemented. In contrast, perceptual decision-making operates at higher levels of the visual hierarchy by integrating sensory information with the internal state of the subject.

Neural correlates of doubt in decision-making

The experience of doubt, the lack of confidence in one's perceptions, internal states, memory and attention, can be due to the variability in occurrence of a phenomenon or can be driven by the internal experience of uncertainty based on subjective evaluation of the environment. Although the experience of some doubt is adaptive in normal cognitive functioning, excessive doubt can significantly impair decision-making and in extreme cases give rise to psychopathology. Although neuroimaging studies have provided some insight into the network of brain areas that is engaged when decision-making involves uncertainty, it remains unclear if dysfunction in these areas also gives rise to the experience and pathological expression of doubt. This study examined the neural correlates of doubt using neuroimaging during the performance of a forced-choice perceptual decision-making task under varying levels of uncertainty in participants who reported either low or high doubt. Participants reporting high doubt exhibited increased activation in the bilateral inferior parietal lobule (IPL) during perceptual decision-making which was not observed in participants who reported low doubt. Furthermore, activity in the IPL in high doubt participants was associated with clinical measures of doubt and showed functional connectivity differences between the high and low doubt groups. The findings of the current study suggest a key role of the IPL and provide a network of brain regions that may play a role in the experience and expression of doubt.

Neural signatures of heterogeneity in risk-taking and strategic consistency

People display a high degree of heterogeneity in risk-taking behaviour, but this heterogeneity remains poorly understood. Here, we use a neural trait approach to examine if task-independent, brain-based differences can help uncover the sources of heterogeneity in risky decision-making. We extend prior research in two key ways. First, we disentangled risk-taking and strategic consistency using novel measures afforded by the Balloon Analogue Risk Task. Second, we applied a personality neuroscience framework to explore why personality traits are typically only weakly related to risk-taking behaviour. We regressed participants' (N = 104) source localized resting-state electroencephalographic activity on risk-taking and strategic consistency. Results revealed that higher levels of resting-state delta-band current density (reflecting reduced cortical activation) in the left dorsal anterior cingulate cortex and the left dorsolateral prefrontal cortex were associated with increased risk-taking and decreased strategic consistency, respectively. These results suggest that heterogeneity in risk-taking behaviour is associated with neural dispositions related to sensitivity to the risk of loss, whereas heterogeneity in strategic consistency is associated with neural dispositions related to strategic decision-making. Finally, extraversion, neuroticism, openness, and self-control were broadly associated with both of the identified neural traits, which in turn mediated indirect associations between personality traits and behavioural measures. These results provide an explanation for the weak direct relationships between personality traits and risk-taking behaviour, supporting a personality neuroscience framework of traits and decision-making.

Hypoactivation in the precuneus and posterior cingulate cortex during ambiguous decision making in individuals with HIV

People with human immunodeficiency virus (HIV) often have neurocognitive impairment. People with HIV make riskier decisions when the outcome probabilities are known, and have abnormal neural architecture underlying risky decision making. However, ambiguous decision making, when the outcome probabilities are unknown, is more common in daily life, but the neural architecture underlying ambiguous decision making in people with HIV is unknown. Eighteen people with HIV and 20 controls completed a decision making task while undergoing functional magnetic resonance imaging scanning. Participants chose between a certain reward and uncertain reward with a known (risky) or unknown (ambiguous) probability of winning. There were three levels of risk: high, medium, and low. Ambiguous > risky brain activity was compared between groups. Ambiguous > risky brain activity was correlated with emotional/psychiatric functioning in people with HIV. Both groups were similarly ambiguity-averse. People with HIV were more risk-averse than controls and chose the high-risk uncertain option less often. People with HIV had hypoactivity in the precuneus, posterior cingulate cortex (PCC), and fusiform gyrus during ambiguous > medium risk decision making. Ambiguous > medium risk brain activity was negatively correlated with emotional/psychiatric functioning in individuals with HIV. To make ambiguous decisions, people with HIV underrecruit key regions of the default mode network, which are thought to integrate internally and externally derived information to come to a decision. These regions and related cognitive processes may be candidates for interventions to improve decision-making outcomes in people with HIV.

Left Frontal EEG Power Responds to Stock Price Changes in a Simulated Asset Bubble Market

Financial bubbles are a result of aggregate irrational behavior and cannot be explained by standard economic pricing theory. Research in neuroeconomics can improve our understanding of their causes. We conducted an experiment in which 28 healthy subjects traded in a simulated market bubble, while scalp EEG was recorded using a low-cost, BCI-friendly desktop device with 14 electrodes. Independent component (IC) analysis was performed to decompose brain signals and the obtained scalp topography was used to cluster the ICs. We computed single-trial time-frequency power relative to the onset of stock price display and estimated the correlation between EEG power and stock price across trials using a general linear model. We found that delta band (1-4 Hz) EEG power within the left frontal region negatively correlated with the trial-by-trial stock prices including the financial bubble. We interpreted the result as stimulus-preceding negativity (SPN) occurring as a dis-inhibition of the resting state network. We conclude that the combination between the desktop-BCI-friendly EEG, the simulated financial bubble and advanced signal processing and statistical approaches could successfully identify the neural correlate of the financial bubble. We add to the neuroeconomics literature a complementary EEG neurometric as a bubble predictor, which can further be explored in future decision-making experiments.

Elevated Inter-Brain Coherence Between Subjects With Concordant Stances During Discussion of Social Issues

Social media platforms offer convenient, instantaneous social sharing on a mass scale with tremendous impact on public perceptions, opinions, and behavior. There is a need to understand why information spreads including the human motivations, cognitive processes, and neural dynamics of large-scale sharing. This study introduces a novel approach for investigating the effect social media messaging and in-person discussion has on the inter-brain dynamics within small groups of participants. The psychophysiological impact of information campaigns and narrative messaging within a closed social media environment was assessed using 24-channel wireless EEG. Data were acquired from three- or four-person groups while subjects debated contemporary social issues framed by four scenarios of varying controversy: (a) investing in ethical vs. unethical corporations, (b) selecting travel destination based on social awareness, (c) determining verdict in a murder trial and the punishment of life in prison or death penalty, and (d) decision to vaccinate. Pre-/post-scenario questionnaires assess the effects of the social media information. Inter-brain coherence between subject pairs on each social issue discussed by subjects was analyzed by concordance, agreement vs. disagreement, and by group unanimity, unanimous vs. not unanimous. Subject pairs that agreed on the social issues raised in the scenarios had significantly greater inter-brain coherence in gamma frequency range than disagreeing pairs over cortical regions known to be involved in social interactions. These effects were magnified when comparing groups where subject pairs were unanimous in their stance on the social issues for some but not all scenarios. While there was considerable overlap between scenarios in what EEG channels were significant, there was enough variability to indicate the possibility of scenario-specific effects on inter-brain coherence.

Neuroanatomical substrates accounting for the effect of present hedonistic time perspective on risk preference: the mediating role of right posterior parietal cortex

The preference for taking risk troubles people across multiple domains including health, economics, and social well-being. Prior research has demonstrated that risk preference can be influenced by time perspective (TP). However, little is known about the neural substrates underlying the effect of TP on risk preference. Here, we used a voxel-based morphometry (VBM) method across two samples to address this question. In Sample 1, the behavioral results showed a positive correlation between present hedonistic TP (PHTP) and gambling rate (the index of risk preference), indicating the higher PHTP, the greater the preference for risk. Subsequently, the whole-brain VBM results found that gambling rate was negatively correlated with the gray matter (GM) volume of a cluster in the right posterior parietal cortex (rPPC). The PHTP score was also negatively related to the GM volume of another cluster in the rPPC. We then examined an overlapping region in the rPPC using a conjunction analysis method. The GM volume of this overlapping brain region was related to both PHTP score and gambling rate. Finally, the mediation analysis found that the GM volume of overlapping region in rPPC played a role in explaining the effect of PHTP on risk preference. This result was also reproduced and validated in another independent sample. Taken together, our findings manifest that the structural variation of rPPC can account for the influence that PHTP has upon the risk preference.

Neural correlates of visual attention during risky decision evidence integration

Value-based decision-making is presumed to involve a dynamic integration process that supports assessing the potential outcomes of different choice options. Decision frameworks assume the value of a decision rests on both the desirability and risk surrounding an outcome. Previous work has highlighted neural representations of risk in the human brain, and their relation to decision choice. Key neural regions including the insula and anterior cingulate cortex (ACC) have been implicated in encoding the effects of risk on decision outcomes, including approach and avoidance. Yet, it remains unknown whether these regions are involved in the dynamic integration processes that precede and drive choice, and their relationship with ongoing attention. Here, we used concurrent fMRI and eye-tracking to discern neural activation related to visual attention preceding choice between sure-thing (i.e. safe) and risky gamble options. We found activation in both dorsal ACC (dACC) and posterior insula (PI) scaled in opposite directions with the difference in attention to risky rewards relative to risky losses. PI activation also differentiated foveations on both risky options (rewards and losses) relative to a sure-thing option. These findings point to ACC involvement in ongoing evaluation of risky but higher value options. The role of PI in risky outcomes points to a more general evaluative role in the decision-making that compares both safe and risky outcomes, irrespective of potential for gains or losses.

Modulation of Dopamine for Adaptive Learning: A Neurocomputational Model

There have been many proposals that learning rates in the brain are adaptive, in the sense that they increase or decrease depending on environmental conditions. The majority of these models are abstract and make no attempt to describe the neural circuitry that implements the proposed computations. This article describes a biologically detailed computational model that overcomes this shortcoming. Specifically, we propose a neural circuit that implements adaptive learning rates by modulating the gain on the dopamine response to reward prediction errors, and we model activity within this circuit at the level of spiking neurons. The model generates a dopamine signal that depends on the size of the tonically active dopamine neuron population and the phasic spike rate. The model was tested successfully against results from two single-neuron recording studies and a fast-scan cyclic voltammetry study. We conclude by discussing the general applicability of the model to dopamine mediated tasks that transcend the experimental phenomena it was initially designed to address.

Contextual Processing and the Impacts of Aging and Neurodegeneration: A Scoping Review

Contextual processing (or context processing; CP) is an integral component of cognition. CP allows people to manage their thoughts and actions by adjusting to surroundings. CP involves the formation of an internal representation of context in relation to the environment, maintenance of this information over a period of time, and the updating of mental representations to reflect changes in the environment. Each of these functions can be affected by aging and associated conditions. Here, we introduced contextual processing research and summarized the literature studying the impact of normal aging and neurodegeneration-related cognitive decline on CP. Through searching the PubMed, PsycINFO, and Google Scholar databases, 23 studies were retrieved that focused on the impact of aging, mild cogniitve impairment (MCI), Alzheimer's disease (AD), and Parkinson's disease (PD) on CP. Results indicated that CP is particularly vulnerable to aging and neurodegeneration. Older adults had a delayed onset and reduced amplitude of electrophysiological response to information detection, comparison, and execution. MCI patients demonstrated clear signs of impaired CP compared to normal aging. The only study on AD suggested a decreased proactive control in AD participants in maintaining contextual information, but seemingly intact reactive control. Studies on PD restricted to non-demented older participants, who showed limited ability to use contextual information in cognitive and motor processes, exhibiting impaired reactive control but more or less intact proactive control. These data suggest that the decline in CP with age is further impacted by accelerated aging and neurodegeneration, providing insights for improving intervention strategies. This review highlights the need for increased attention to research this important but understudied field.

Neural Computations of Threat

A host of learning, memory, and decision-making processes form the individual's response to threat and may be disrupted in anxiety and post-trauma psychopathology. Here we review the neural computations of threat, from the first encounter with a dangerous situation, through learning, storing, and updating cues that predict it, to making decisions about the optimal course of action. The overview highlights the interconnected nature of these processes and their reliance on shared neural and computational mechanisms. We propose an integrative approach to the study of threat-related processes, in which specific computations are studied across the various stages of threat experience rather than in isolation. This approach can generate new insights about the evolution, diagnosis, and treatment of threat-related psychopathology.

Modulation of cue-guided choices by transcranial direct current stimulation

Environmental cues may anticipate the availability of rewards, thus acting as a guide towards a specific choice (i.e., cue-guided choices). Despite the lateral prefrontal cortex having a critical role in using past learning and flexibly selecting relevant information to guide behavior, the literature on the neural basis of human cue-guided choice mainly focused on the subcortical brain structures implicated, while the specific role of cortical areas remained unclear. The present study aimed to provide causal evidence for the involvement of the lateral prefrontal cortex in two forms of human cue-guided choice, namely outcome-specific and general. To do this, 2 mA cathodal, anodal or sham transcranial direct current stimulation was applied over the lateral prefrontal cortex (with the posterior parietal cortex serving as control region) in three separate groups performing a Pavlovian-to-Instrumental Transfer task. Results showed, for the first time, a dissociation in the cortical structures involved in human cue-guided choice. Cathodal stimulation of the lateral prefrontal cortex reduced the outcome-specific transfer. In striking contrast, there was no influence on the general transfer. These results argue in favor of the presence of at least two possible neural pathways underlying cue-guided choices.

Between Action and Emotional Survival During the COVID-19 era: Sensorimotor Pathways as Control Systems of Transdiagnostic Anxiety-Related Intolerance to Uncertainty

Objectives: The COVID-19 pandemic and aligned social and physical distancing regulations increase the sense of uncertainty, intensifying the risk for psychopathology globally. Anxiety disorders are associated with intolerance to uncertainty. In this review we describe brain circuits and sensorimotor pathways involved in human reactions to uncertainty. We present the healthy mode of coping with uncertainty and discuss deviations from this mode. Methods: Literature search of PubMed and Google Scholar. Results: As manifestation of anxiety disorders includes peripheral reactions and negative cognitions, we suggest an integrative model of threat cognitions modulated by sensorimotor regions: "The Sensorimotor-Cognitive-Integration-Circuit." The model emphasizes autonomic nervous system coupling with the cortex, addressing peripheral anxious reactions to uncertainty, pathways connecting cortical regions and cost-reward evaluation circuits to sensorimotor regions, filtered by the amygdala and basal ganglia. Of special interest are the ascending and descending tracts for sensory-motor crosstalk in healthy and pathological conditions. We include arguments regarding uncertainty in anxiety reactions to the pandemic and derive from our model treatment suggestions which are supported by scientific evidence. Our model is based on systematic control theories and emphasizes the role of goal conflict regulation in health and pathology. We also address anxiety reactions as a spectrum ranging from healthy to pathological coping with uncertainty, and present this spectrum as a transdiagnostic entity in accordance with recent claims and models. Conclusions: The human need for controllability and predictability suggests that anxiety disorders reactive to the pandemic's uncertainties reflect pathological disorganization of top-down bottom-up signaling and neural noise resulting from non-pathological human needs for coherence in life.

Relationship between BMI and alcohol consumption levels in decision making

BACKGROUND

Decision-making deficits in obesity and alcohol use disorder (AUD) may contribute to the choice of immediate rewards despite their long-term deleterious consequences.

METHODS

Gambling task functional MRI in Human connectome project (HCP) dataset was used to investigate neural activation differences associated with reward or punishment (a key component of decision-making behavior) in 418 individuals with obesity (high BMI) and without obesity (lean BMI) and either at high (HR) or low (LR) risk of AUD based on their alcohol drinking levels.

RESULTS

Interaction between BMI and alcohol drinking was seen in regions of the default mode network (DMN) and those implicated in self-related processing, memory, and salience attribution. ObesityHR relative to obesityLR also recruited DMN along with primary motor and regions implicated in inattention, negative perception, and uncertain choices, which might facilitate impulsive choices in obesityHR. Furthermore, obesityHR compared to leanHR/leanLR also demonstrated heightened activation in DMN and regions implicated in uncertain decisions.

CONCLUSIONS

These results suggest that BMI is an independent variable from that of alcohol drinking levels in neural processing of gambling tasks. Moreover, leanLR relative to leanHR, showed increased activation in motor regions [precentral and superior frontal gyrus] suggestive of worse executive function from excessive alcohol use. Delayed discounting measures failed to distinguish between obesity and high alcohol drinking levels, which as for gambling task results suggests independent negative effects of obesity and chronic alcohol drinking on decision-making. These findings highlight distinct associations of obesity and high-risk alcohol drinking with two key constituents of decision-making behavior.

Multimodal Sensory-Spatial Integration and Retrieval of Trained Motor Patterns for Body Coordination in Musicians and Dancers

Dancers and musicians are experts in spatial and temporal processing, which allows them to coordinate movement with music. This high-level processing has been associated with structural and functional adaptation of the brain for high performance sensorimotor integration. For these integration processes, adaptation does not only take place in primary and secondary sensory and motor areas but also in tertiary brain areas, such as the lateral prefrontal cortex (lPFC) and the intraparietal sulcus (IPS), providing vital resources for highly specialized performance. Here, we review evidence for the role of these brain areas in multimodal training protocols and integrate these findings into a new model of sensorimotor processing in complex motor learning.

Retrospective Valuation of Experienced Outcome Encoded in Distinct Reward Representations in the Anterior Insula and Amygdala

Our ability to evaluate an experience retrospectively is important because it allows us to summarize its total value, and this summary value can then later be used as a guide in deciding whether the experience merits repeating, or whether instead it should rather be avoided. However, when an experience unfolds over time, humans tend to assign disproportionate weight to the later part of the experience, and this can lead to poor choice in repeating, or avoiding experience. Using model-based computational analyses of fMRI recordings in 27 male volunteers, we show that the human brain encodes the summary value of an extended sequence of outcomes in two distinct reward representations. We find that the overall experienced value is encoded accurately in the amygdala, but its merit is excessively marked down by disincentive anterior insula activity if the sequence of experienced outcomes declines temporarily. Moreover, the statistical strength of this neural code can separate efficient decision-makers from suboptimal decision-makers. Optimal decision-makers encode overall value more strongly, and suboptimal decision-makers encode the disincentive markdown (DM) more strongly. The separate neural implementation of the two distinct reward representations confirms that suboptimal choice for temporally extended outcomes can be the result of robust neural representation of a displeasing aspect of the experience such as temporary decline.SIGNIFICANCE STATEMENT One of the numerous foibles that prompt us to make poor decisions is known as the "Banker's fallacy," the tendency to focus on short-term growth at the expense of long-term value. This effect leads to unwarranted preference for happy endings. Here, we show that the anterior insula in the human brain marks down the overall value of an experience as it unfolds over time if the experience entails a sequence of predominantly negative temporal contrasts. By contrast, the amygdala encodes overall value accurately. These results provide neural indices for the dichotomy of decision utility and experienced utility popularized as Thinking fast and slow by Daniel Kahneman.

Neural tracking of subjective value under riskand ambiguity in adolescence

Although many neuroimaging studies on adolescent risk taking have focused on brain activation during outcome valuation, less attention has been paid to the neural correlates of choice valuation. Subjective choice valuation may be particularly influenced by whether a choice presents risk (known probabilities) or ambiguity (unknown probabilities), which has rarely been studied in developmental samples. Therefore, we examined the neural tracking of subjective value during choice under risk and ambiguity in a large sample of adolescents (N = 188, 12–22 years). Specifically, we investigated which brain regions tracked subjective value coding under risk and ambiguity. A model-based approach to estimate individuals’ risk and ambiguity attitudes showed prominent variation in individuals’ aversions to risk and ambiguity. Furthermore, participants subjectively experienced the ambiguous options as being riskier than the risky options. Subjective value tracking under risk was coded by activation in ventral striatum and superior parietal cortex. Subjective value tracking under ambiguity was coded by dorsolateral prefrontal cortex (PFC) and superior temporal gyrus activation. Finally, overlapping activation in the dorsomedial PFC was observed for subjective value under both conditions. Overall, this is the first study to chart brain activation patterns for subjective choice valuation under risk and ambiguity in an adolescent sample, which shows that the building blocks for risk and ambiguity processing are already present in early adolescence. Finally, we highlight the potential of combining behavioral modeling with fMRI for investigating choice valuation in adolescence, which may ultimately aid in understanding who takes risks and why.

Sweating the small stuff: A meta-analysis of skin conductance on the Iowa gambling task

To systematically examine the role of anticipatory skin conductance responses (aSCRs) in predicting Iowa Gambling Task (IGT) performance. Secondly, to assess the quality of aSCR evidence for the Somatic Marker Hypothesis (SMH) during the IGT. Finally, to evaluate the reliability of current psychophysiological measurements on the IGT. Electronic databases, journals and reference lists were examined for inclusion. Data were extracted by two reviewers and validated by another reviewer, using a standardised extraction sheet along with a quality assessment. Two meta-analyses of aSCR measures were conducted to test the relationship between overall aSCR and IGT performance, and differences in aSCR between advantageous and disadvantageous decks. Twenty studies were included in this review. Quality assessment revealed that five studies did not measure anticipatory responses, and few stated they followed standard IGT and/or psychophysiological procedures. The first meta-analysis of 15 studies revealed a significant, small-to-medium relationship between aSCR and IGT performance (r= .22). The second meta-analysis of eight studies revealed a significant, small difference in aSCR between the advantageous and disadvantageous decks (r= .10); however, publication bias is likely to be an issue. Meta-analyses revealed aSCR evidence supporting the SMH. However, inconsistencies in the IGT and psychophysiological methods, along with publication bias, cast doubt on these effects. It is recommended that future tests of the SMH use a range of psychophysiological measures, a standardised IGT protocol, and discriminate between advantageous and disadvantageous decks.

Neural sensitivity to risk in adults with co-occurring HIV infection and cocaine use disorder

Persons with co-occurring HIV infection and cocaine use disorder tend to engage in riskier decision-making. However, the neural correlates of sensitivity to risk are not well-characterized in this population. The purpose of this study was to examine the neural interaction effects of HIV infection and cocaine use disorder to sensitivity to risk. The sample included 79 adults who differed on HIV status and cocaine use disorder. During functional magnetic resonance imaging (fMRI), participants completed a Wheel of Fortune (WoF) task that assessed neural activation in response to variations of monetary risk (i.e., lower probability of winning a larger reward). Across groups, neural activation to increasing risk was in cortical and subcortical regions similar to previous investigations using the WoF in nondrug-using populations. Our analyses showed that there was a synergistic effect between HIV infection and cocaine use in the left precuneus/posterior cingulate cortex and hippocampus, and right postcentral gyrus, lateral occipital cortex, cerebellum, and posterior parietal cortex. HIV+ individuals with cocaine use disorder displayed neural hyperactivation to increasing risk that was not observed in the other groups. These results support a synergistic effect of co-occurring HIV infection and cocaine dependence in neural processing of risk probability that may reflect compensation. Future studies can further investigate and validate how neural activation to increasing risk is associated with risk-taking behavior.

Dopaminergic modulation of the exploration/exploitation trade-off in human decision-making

Involvement of dopamine in regulating exploration during decision-making has long been hypothesized, but direct causal evidence in humans is still lacking. Here, we use a combination of computational modeling, pharmacological intervention and functional magnetic resonance imaging to address this issue. Thirty-one healthy male participants performed a restless four-armed bandit task in a within-subjects design under three drug conditions: 150 mg of the dopamine precursor L-dopa, 2 mg of the D2 receptor antagonist haloperidol, and placebo. Choices were best explained by an extension of an established Bayesian learning model accounting for perseveration, directed exploration and random exploration. Modeling revealed attenuated directed exploration under L-dopa, while neural signatures of exploration, exploitation and prediction error were unaffected. Instead, L-dopa attenuated neural representations of overall uncertainty in insula and dorsal anterior cingulate cortex. Our results highlight the computational role of these regions in exploration and suggest that dopamine modulates how this circuit tracks accumulating uncertainty during decision-making.

Affective evaluation of others' altruistic decisions under risk and ambiguity

Gratitude arises when one is the target of an altruistic decision, particularly when this decision incurs cost to the agent. Here we examined how individuals evaluate others' altruistic decisions under risky (uncertainty with known probabilities) and ambiguous (uncertainty with unknown probabilities) costs and respond with gratitude and reciprocity. Participants played an interactive game in an fMRI scanner in which they would receive painful electric shocks. An anonymous co-player either intentionally (Human conditions) or unintentionally (Computer conditions) decided whether to help the participant reduce half of the pain by undertaking an amount of pain (i.e., cost) with varying level of uncertainty (Certain vs. Risky vs. Ambiguous). Participants could then transfer monetary points to the co-player knowing that the co-player was unaware of this transfer. Behaviorally, monetary allocation and gratitude rating increased as the uncertainty level of cost increased in Human conditions; these effects were reduced in Computer conditions. The effect of cost uncertainty on gratitude was mediated by the perceived kind intention behind the help. FMRI revealed both shared and differential neurocognitive substrates for evaluating the benefactor's altruistic decisions under risk and ambiguity: both were associated with fear- and anxiety-related processes, involving right lateral orbitofrontal cortex and anterior insula; ambiguity additionally recruited mentalizing- and conflict monitoring-related processes, involving dorsal medial prefrontal cortex and dorsal anterior cingulate cortex. These findings underscore the crucial role of social uncertainty perception in the generation of gratitude.

Dissociable neural correlates of uncertainty underlie different exploration strategies

Most real-world decisions involve a delicate balance between exploring unfamiliar alternatives and committing to the best known option. Previous work has shown that humans rely on different forms of uncertainty to negotiate this "explore-exploit" trade-off, yet the neural basis of the underlying computations remains unclear. Using fMRI (n = 31), we find that relative uncertainty is represented in right rostrolateral prefrontal cortex and drives directed exploration, while total uncertainty is represented in right dorsolateral prefrontal cortex and drives random exploration. The decision value signal combining relative and total uncertainty to compute choice is reflected in motor cortex activity. The variance of this signal scales with total uncertainty, consistent with a sampling mechanism for random exploration. Overall, these results are consistent with a hybrid computational architecture in which different uncertainty computations are performed separately and then combined by downstream decision circuits to compute choice.