Etienne Koechlin

Ecole Normale Supérieure de Paris | ENS · Laboratoire de Neurosciences Cognitives

Value-based decision making in complex environments, such as those with uncertain and volatile mapping of reward probabilities onto options, may engender computational strategies that are not necessarily optimal in terms of normative frameworks but may ensure effective learning and behavioral flexibility in conditions of limited neural computationa...

The real world is uncertain, and while ever changing, it constantly presents itself in terms of new sets of behavioral options. To attain the flexibility required to tackle these challenges successfully, most mammalian brains are equipped with certain computational abilities that rely on the prefrontal cortex (PFC). By examining learning in terms o...

In everyday life, humans face environments that feature uncertain and volatile or changing situations. Efficient adaptive behaviour must take into account uncertainty and volatility. Previous models of adaptive behaviour involve inferences about volatility that rely on complex and often intractable computations. Because such computations are presum...

Everyday life often requires arbitrating between pursuing an ongoing action plan by possibly adjusting it versus exploring a new action plan instead. Resolving this so-called exploitation-exploration dilemma involves the medial prefrontal cortex (mPFC). Using human intracranial electrophysiological recordings, we discovered that neural activity in...

Depending on environmental demands, humans can learn and exploit multiple concurrent sets of stimulus-response associations. Mechanisms underlying the learning of such task-sets remain unknown. Here we investigate the hypothesis that task-set learning relies on unsupervised chunking of stimulus-response associations that occur in temporal proximity...

Depending on environmental demands, humans can learn and exploit multiple concurrent sets of stimulus-response associations. Mechanisms underlying the learning of such task-sets remain unknown. Here we investigate the hypothesis that task-set learning relies on unsupervised chunking of stimulus-response associations that occur in temporal proximity...

Depending on environmental demands, humans can learn and exploit multiple concurrent sets of stimulus-response associations. Mechanisms underlying the learning of such task-sets remain unknown. Here we investigate the hypothesis that task-set learning relies on unsupervised chunking of stimulus-response associations that occur in temporal proximity...

Two recent studies (Farashahi et al. and Rouault et al.) provide compelling evidence refuting the Subjective Expected Utility (SEU) hypothesis as a ground model describing human decision-making. Together, these studies pave the way towards a new model that subsumes the notion of decision-making and adaptive behavior into a single account.

Everyday life features uncertain and ever-changing situations. In such environments, optimal adaptive behavior requires higher-order inferential capabilities to grasp the volatility of external contingencies. These capabilities however involve complex and rapidly intractable computations, so that we poorly understand how humans develop efficient ad...

Depending on environmental demands, humans can learn and exploit multiple concurrent sets of stimulus-response associations. Mechanisms underlying the learning of such task-sets remain unknown. Here we investigate the hypothesis that task-set learning relies on unsupervised chunking of stimulus-response associations that occur in temporal proximity...

In uncertain and changing environments, optimal decision-making requires integrating reward expectations with probabilistic beliefs about reward contingencies. Little is known, however, about how the prefrontal cortex (PFC), which subserves decision-making, combines these quantities. Here, using computational modelling and neuroimaging, we show tha...

Most people envision themselves as operant agents endowed with the capacity to bring about changes in the outside world. This ability to monitor one's own causal power has long been suggested to rest upon a specific model of causal inference, i.e., a model of how our actions causally relate to their consequences. What this model is and how it may e...

Humans are set apart from other animals by many elements of advanced cognition and behaviour, including language, judgement and reasoning. What is special about the human brain that gives rise to these abilities? Could the foremost part of the prefrontal cortex (the frontopolar cortex), which has become considerably enlarged in humans during evolut...

Personality has an important influence on the variability in human decision making. Little is known whether intensive training and a highly-procedural environment can alleviate the influence of personality on decision making. Here, we address this issue by investigating the influence of impulsivity as personality factor on decision making among air...

The human prefrontal cortex (PFC) subserves cognitive control, that is, the ability to form behavioral strategies that coordinate actions and thoughts in relation to internal goals. Cognitive control involves the medial and lateral PFC but we still poorly understand how these regions guide strategy selection according to expected rewards. We addres...

In the past decade the field of cognitive sciences has seen an exponential growth in the number of computational modeling studies. Previous work has indicated why and how candidate models of cognition should be compared by trading off their ability to predict the observed data as a function of their complexity. However, the importance of falsifying...

The ability to infer other people’s intentions is crucial for successful human social interactions. Such inference relies on an adaptive interplay of sensory evidence and prior expectations. Crucially, this interplay would also depend on the type of intention inferred, i.e., on how abstract the intention is. However, what neural mechanisms adjust t...

This chapter provides a brief overview of the anatomical organisation of the human prefrontal cortex (PFC) sub serving cognitive control. The core function of cognitive control is to arbitrate between staying with the current behavioural strategy, and adjusting it through reinforcement learning (RL)-versus retrieving previously learned strategies o...

Current neural models of value-based decision-making consider choices as a 2-stage process, proceeding from the " valuation " of each option under consideration to the " selection " of the best option on the basis of their subjective values. However, little is known about the computational mechanisms at play at the selection stage and its implement...

Making decisions in uncertain environments often requires combining multiple pieces of ambiguous information from external cues. In such conditions, human choices resemble optimal Bayesian inference, but typically show a large suboptimal variability whose origin remains poorly understood. In particular, this choice suboptimality might arise from im...

Cognitive neuroscience, especially in the fields of learning and decision-making, is witnessing the blossoming of computational model-based analyses. Several methodological and review papers have indicated how and why candidate models should be compared by trading off their ability to predict the data as a function of their complexity. However, the...

Making decisions under uncertainty, from perceptual judgments to reward-guided choices, requires combining multiple pieces of decision-relevant information—a cognitive process modeled as statistical inference. In such conditions, human and animal decisions exhibit a large suboptimal variability whose origin and structure remains poorly understood....

The prefrontal cortex (PFC) subserves higher cognitive abilities such as planning, reasoning and creativity. Here we review recent findings from both empirical and theoretical studies providing new insights about these cognitive abilities and their neural underpinnings in the PFC as overcoming key adaptive limitations in reinforcement learning. We...

The frontopolar cortex (FPC), the most anterior part of the lateral prefrontal cortex corresponding to Brodmann area 10, is involved in human high-order cognition, including reasoning, problem-solving and multitasking. Its specific contribution to prefrontal executive function, however, remains unclear. A neurocomputational model suggests that the...

The prefrontal cortex (PFC) subserves decision-making and executive control. Here we review recent empirical and modeling works with a focus on neuroimaging studies, which start unifying these two conceptual approaches of PFC function. We propose that the PFC comprises two arbitration systems: (1) a peripheral system comprising premotor/caudal PFC...

The prefrontal cortex subserves executive control and decision-making, that is, the coordination and selection of thoughts and actions in the service of adaptive behaviour. We present here a computational theory describing the evolution of the prefrontal cortex from rodents to humans as gradually adding new inferential Bayesian capabilities for dea...

The prefrontal cortex (PFC) subserves reasoning in the service of adaptive behavior. Little is known, however, about the architecture of reasoning processes in the PFC. Using computational modeling and neuroimaging, we show here that the human PFC has two concurrent inferential tracks: (i) one from ventromedial to dorsomedial PFC regions that makes...

The cascade model of cognitive control, mostly relying on functional neuroimaging studies, stipulates that the lateral frontal cortex (LFC) is organized as a cascade of executive processes involving three levels of cognitive control, implemented in distinct LFC areas from the premotor to the anterior prefrontal regions. The present experiment teste...

Irrelevant contextual changes within episodes. Left, proportions of correct responses produced by context-, outcome-exploiting, and exploring participants on trials preceding and following changes in contextual cues within control episodes (Experiment 2). Contextual cues changed in Trial T, whereas the mapping between stimuli and best responses rem...

Human performances and PROBE model fit with four recurrent action sets. Shaded lines, performances from 30 healthy participants (16 females, aged 18–30 years old) in recurrent episodes plotted against the number of trials following episode onset. Shaded areas are S.E.M. across participants (detailed legend in Figure 1). The experimental session con...

Supplementary methods. (PDF)

Trial structure in Experiments 1 and 2. (A) First experiment. Visual stimuli were pseudo-randomly drawn from a set of three arabic numbers (e.g., (1, 3, 5)). Participants had to respond by pressing one among four possible response keys. 100 ms after participants' responses, stimuli were removed and positive or negative feedback was presented during...

Best fitting parameters in the PROBE model across participants' group used in Figures 6 and 7. Mean(S.E.M.) across participants. See Materials and Methods for detailed parameter description. Boxes indicate significant differences across groups (see text). (PDF)

Architecture of task sets. The monitoring buffer comprises a limited number of task sets, each indexing a behavioral strategy stored in long-term memory and comprising a selective, predictive, and contextual mapping (M). The reliability of each task set is monitored online at two time points: right before acting (ex-ante reliability λi) and right a...

Performance of the statistical optimal model. Graphs show the best achievable performance in terms of information processing in Experiment 1. The statistical optimal model is described in Text S1, 1-Normative approach to the PROBE model, optimal statistical model. Red, recurrent episodes; green, open episodes. The best achievable performance is obt...

Best fitting model parameters used in Figures 3 and 5. Mean(S.E.M.) across participants. See Materials and Methods for detailed parameter description. (PDF)

The frontal lobes subserve decision-making and executive control--that is, the selection and coordination of goal-directed behaviors. Current models of frontal executive function, however, do not explain human decision-making in everyday environments featuring uncertain, changing, and especially open-ended situations. Here, we propose a computation...

Humans and monkeys can learn to classify perceptual information in a statistically optimal fashion if the functional groupings remain stable over many hundreds of trials, but little is known about categorization when the environment changes rapidly. Here, we used a combination of computational modeling and functional neuroimaging to understand how...

Basic experiment: psychometric curve fit to the cumulative distribution of participant's correct responses (red dots). Responses for the different actions were pooled across. The blue dot refers to the inflexion point of the sigmoid curve. In each experiment, the inflexion point occurs at the following duration: A. Basic: 1576 ms. B. Superord.: 155...

Pre-tests: intra- and inter-sequence comparisons; selection of low, moderate and high amounts of information. (DOC)

Distribution of participant's reaction times (blue dots) across the 12 movie segments. Reaction times for the different actions were pooled across subjects. Red squares: mean reaction times across participants for each of the 12 duration ranges. (TIF)

Explaining or predicting the behaviour of our conspecifics requires the ability to infer the intentions that motivate it. Such inferences are assumed to rely on two types of information: (1) the sensory information conveyed by movement kinematics and (2) the observer's prior expectations--acquired from past experience or derived from prior knowledg...

An observer detecting a noisy sensory signal is biased by the costs and benefits associated with its presence or absence. When these costs and benefits are asymmetric, sensory, and economic information must be integrated to inform the final choice. However, it remains unknown how this information is combined at the neural or computational levels. T...

The anterior prefrontal cortex (APC) confers on humans the ability to simultaneously pursue several goals. How does the brain's motivational system, including the medial frontal cortex (MFC), drive the pursuit of concurrent goals? Using brain imaging, we observed that the left and right MFC, which jointly drive single-task performance according to...

The prefrontal cortex (PFC) subserves cognitive control, that is, the ability to select thoughts or actions in relation to internal goals. Little is known, however, about how the PFC combines motivation and the selection processes underlying cognitive control. We used functional magnetic resonance imaging in humans and found that the medial and lat...

Cognitive control is highly affected in schizophrenia, but its overall functional architecture remains poorly understood. A recent study demonstrated that, in healthy subjects, cognitive control is functionally organized within the lateral prefrontal cortex (LPFC) as a cascade of representations ranging from premotor to anterior LPFC regions accord...

Measuring the cognitive and neural sequelae of switching between tasks permits a window into the flexible functioning of the executive control system. Prolonged reaction times (RTs) after task switches are accompanied by increases in brain activity in the anterior cingulate cortex (ACC) and dorsolateral prefrontal cortex (dlPFC), but the contributi...

Correlation coefficient in the branching condition for each possible n-1 subset of data sample. (0.03 MB DOC)

Correlation coefficient in the dual-task condition for each possible n-1 subset of data sample. (0.02 MB DOC)

Perceptual inference is biased by foreknowledge about what is probable or possible. How prior expectations are neurally represented during visual perception, however, remains unknown. We used functional magnetic resonance imaging to measure brain activity in humans judging simple visual stimuli. Perceptual decisions were either biased in favor of a...

Executive dysfunctions have long been considered a common feature of schizophrenia. However, due to their extreme heterogeneity, it is not clear whether these impairments take place at a particular level of executive functioning or non-specifically affect various aspects of behavioural control. To answer this question, we used an experimental parad...

A major question in understanding the functional organization of the brain is to delineate the functional divisions of the prefrontal cortex. Of particular importance to the cognitive capacities that are uniquely human is the fronto-polar cortex (Brodmann's area 10), which is disproportionally larger in humans relative to the rest of the brain than...

The frontopolar cortex (FPC), the most anterior part of the frontal lobes, forms the apex of the executive system underlying decision-making. Here, we review empirical evidence showing that the FPC function enables contingent interposition of two concurrent behavioral plans or mental tasks according to respective reward expectations, overcoming the...

The parietal cortex is involved in a wide range of cognitive functions in humans including associative functions between multiple sensorimotor spaces, attentional control, and working memory. Little is known, however, about the role and the functional organization of the parietal cortex in action planning and sequential cognition. Moreover, the res...

The prefrontal cortex subserves executive control--that is, the ability to select actions or thoughts in relation to internal goals. Here, we propose a theory that draws upon concepts from information theory to describe the architecture of executive control in the lateral prefrontal cortex. Supported by evidence from brain imaging in human subjects...

Introduction Le cortex préfrontal (CPF) sous-tend les mécanismes d’adaptation du comportement, et joue un rôle central dans le contrôle de l’action. À ce jour, son organisation fonctionnelle reste débattue, et aucun modèle ne s’est imposé. Objectifs Grâce à une étude comportementale en IRM fonctionnelle, E. Koechlin et son équipe ont proposé un no...

Incoming sensory information is often ambiguous, and the brain has to make decisions during perception. “Predictive coding” proposes that the brain resolves perceptual ambiguity by anticipating the forthcoming sensory environment, generating a template against which to match observed sensory evidence. We observed a neural representation of predicte...

The prefrontal cortex subserves executive control, i.e., the organization of action or thought in relation to internal goals. This brain region hosts a system of executive processes extending from premotor to the most anterior prefrontal regions that governs the temporal organization of behavior. Little is known, however, about the prefrontal execu...

The prefrontal cortex (PFC) subserves cognitive control: the ability to coordinate thoughts or actions in relation with internal goals. Its functional architecture, however, remains poorly understood. Using brain imaging in humans, we showed that the lateral PFC is organized as a cascade of executive processes from premotor to anterior PFC regions...