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The human brain excels at constructing and using abstractions, such as rules, or concepts. Here, in two fMRI experiments, we demonstrate a mechanism of abstraction built upon the valuation of sensory features. Human volunteers learned novel association rules based on simple visual features. Reinforcement-learning algorithms revealed that, with learning, high-value abstract representations increasingly guided participant behaviour, resulting in better choices and higher subjective confidence. We also found that the brain area computing value signals – the ventromedial prefrontal cortex – prioritised and selected latent task elements during abstraction, both locally and through its connection to the visual cortex. Such a coding scheme predicts a causal role for valuation. Hence, in a second experiment, we used multivoxel neural reinforcement to test for the causality of feature valuation in the sensory cortex, as a mechanism of abstraction. Tagging the neural representation of a task feature with rewards evoked abstraction-based decisions. Together, these findings provide a novel interpretation of value as a goal-dependent, key factor in forging abstract representations.

Uncertainty is ubiquitous in cognitive processing, which is why agents require a precise handle on how to deal with the noise inherent in their mental operations. Previous research suggests that people possess a remarkable ability to track and report uncertainty, often in the form of confidence judgments. Here, we argue that humans use uncertainty inherent in their representations of value beliefs to arbitrate between exploration and exploitation. Such uncertainty is reflected in explicit confidence judgments. Using a novel variant of a multi-armed bandit paradigm, we studied how beliefs were formed and how uncertainty in the encoding of these value beliefs (belief confidence) evolved over time. We found that people used uncertainty to arbitrate between exploration and exploitation, reflected in a higher tendency towards exploration when their confidence in their value representations was low. We furthermore found that value uncertainty can be linked to frameworks of metacognition in decision making in two ways. First, belief confidence drives decision confidence—that is people’s evaluation of their own choices. Second, individuals with higher metacognitive insight into their choices were also better at tracing the uncertainty in their environment. Together, these findings argue that such uncertainty representations play a key role in the context of cognitive control.

Artificial intelligence algorithms are capable of fantastic exploits, yet they are still grossly inefficient compared with the brain’s ability to learn from few exemplars or solve problems that have not been explicitly defined. What is the secret that the evolution of human intelligence has unlocked? Generalization is one answer, but there is more to it. The brain does not directly solve difficult problems, it is able to recast them into new and more tractable problems. Here, we propose a model whereby higher cognitive functions profoundly interact with reinforcement learning to drastically reduce the degrees of freedom of the search space, simplifying complex problems, and fostering more efficient learning.

One of the puzzles in neuroeconomics is the inconsistent pattern of brain response seen in the striatum during evaluation of losses. In some studies striatal responses appear to represent loss as a negative reward (BOLD deactivation), while in others as positive punishment (BOLD activation). We argue that these discrepancies can be explained by the existence of two fundamentally different types of loss: excitatory losses signaling the presence of substantive punishment, and inhibitory losses signaling cessation or omission of reward. We then map different theories of motivational opponency to loss related decision-making, and highlight five distinct underlying computational processes. We suggest that this excitatory–inhibitory model of loss provides a neurobiological framework for understanding reference dependence in behavioral economics.

Every time we make a choice, we maintain an explicit representation of our confidence in that choice. Using eye-tracking and behavioural measures, the authors show that tracking decision uncertainty is helpful in guiding future behaviour.

The emotional responses elicited by the way options are framed often results in lack of logical consistency in human decision making. In this study, we investigated subjects with autism spectrum disorder (ASD) using a financial task in which the monetary prospects were presented as either loss or gain. We report both behavioral evidence that ASD subjects show a reduced susceptibility to the framing effect and psycho-physiological evidence that they fail to incorporate emotional context into the decision-making process. On this basis, we suggest that this insensitivity to contextual frame, although enhancing choice consistency in ASD, may also underpin core deficits in this disorder. These data highlight both benefits and costs arising from multiple decision processes in human cognition.

Animal research suggests that the consolidation of fear and extinction memories depends on N-methyl D-aspartate (NMDA)- type glutamate receptors. Using a fear conditioning and extinction paradigm in healthy normal volunteers, we show that postlearning administration of the NMDA partial agonist D-cycloserine (DCS) facilitates fear memory consolidation, evidenced behaviorally by enhanced skin conductance responses, relative to placebo, for presentations of a conditioned stimulus (CS) at a memory test performed 72 h later. DCS also enhanced CS-evoked neural responses in a posterior hippocampus/collateral sulcus region and in the medial prefrontal cortex at test. Our data suggest a role for NMDA receptors in regulating fear memory consolidation in humans.

The ability to process stimuli that convey potential threat, under conditions of limited attentional resources, confers adaptive advantages. This study examined the neurobiology underpinnings of this capacity. Employing an attentional blink paradigm, in conjunction with functional magnetic resonance imaging (fMRI), we manipulated the salience of the second of two face target stimuli (T2), by varying emotionality. Behaviourally, fearful T2 faces were identified significantly more than neutral faces. Activity in fusiform face area (FFA) increased with correct identification of T2 faces. Enhanced activity in rostral anterior cingulate cortex (rACC) accounted for the benefit in detection of fearful stimuli reflected in a significant interaction between target valence and correct identification. Thus, under conditions of limited attention resources activation in rACC correlated with enhanced processing of emotional stimuli. We suggest that these data support a model in which a prefrontal “gate” mechanism controls conscious access of emotional information under conditions of limited attentional resources.

Recent research indicating that bilingualism is associated with enhanced executive function suggests that this enhancement may operate within a broader spectrum of cognitive abilities than previously thought (e.g., Stocco & Prat, 2014). In this study, we focus on metacognition or the ability to evaluate one’s own cognitive performance (Flavell, 1979). Over the course of two experiments, we presented young healthy adult monolinguals and bilinguals with a perceptual two-alternative-forced-choice task followed by confidence judgements. Results from both experiments indicated that bilingual participants showed a disadvantage in metacognitive efficiency, determined through the calculation of Mratio (Maniscalco & Lau, 2014). Our findings provide novel insight into the potential differences in bilingual and monolingual cognition, which may indicate a bilingual disadvantage. Results are discussed with reference to the balance of advantages versus disadvantages associated with multilanguage learning.

Decisions are never perfect, with confidence in one's choices fluctuating over time. How subjective confidence and valuation of choice options interact at the level of brain and behavior is unknown. Using a dynamic model of the decision process, we show that confidence reflects the evolution of a decision variable over time, explaining the observed relation between confidence, value, accuracy and reaction time. As predicted by our dynamic model, we show that a functional magnetic resonance imaging signal in human ventromedial prefrontal cortex (vmPFC) reflects both value comparison and confidence in the value comparison process. Crucially, individuals varied in how they related confidence to accuracy, allowing us to show that this introspective ability is predicted by a measure of functional connectivity between vmPFC and rostrolateral prefrontal cortex. Our findings provide a mechanistic link between noise in value comparison and metacognitive awareness of choice, enabling us both to want and to express knowledge of what we want. © 2013 Nature America, Inc. All rights reserved.

Summary Employers often make payment contingent on performance in order to motivate workers. We used fMRI with a novel incentivized skill task to examine the neural processes underlying behavioral responses to performance-based pay. We found that individuals' performance increased with increasing incentives; however, very high incentive levels led to the paradoxical consequence of worse performance. Between initial incentive presentation and task execution, striatal activity rapidly switched between activation and deactivation in response to increasing incentives. Critically, decrements in performance and striatal deactivations were directly predicted by an independent measure of behavioral loss aversion. These results suggest that incentives associated with successful task performance are initially encoded as a potential gain; however, when actually performing a task, individuals encode the potential loss that would arise from failure., Highlights ► Very high monetary incentives result in poor behavioral performance ► During incentive presentation, striatal activity increases with increasing incentives ► During task performance, striatal activity decreases with increasing incentives ► Performance and striatal responses are predicted by behavioral loss aversion, Chib et al. find that very large financial incentives can lead to the paradoxical response of poor work performance. Imaging results suggest that these decreases in performance are caused by individuals encoding the potential monetary loss that would arise from failure.

Introduction Norepinephrine (NE) has a regulatory role in human attention. Objective To examine its role in emotional modulation of attention, we used an attentional blink (AB) paradigm, in the context of psychopharmacological manipulation, where targets were either emotional or neutral items. Results and discussion We report behavioural evidence that β-adrenergic blockade with propranolol impairs attention independent of target valence. Furthermore, this effect is centrally mediated as administration of the peripheral β-adrenergic antagonist nadolol did not impair attention. By contrast, increasing NE tone, using the selective NE reuptake inhibitor reboxetine, improves detection of emotional stimuli. Conclusion In line with theoretical and animal models, these findings provide human behavioural evidence that the adrenergic system has a modulatory influence on selective attention that in some instances depends on item valence.