Christoph W. Korn

Universität Heidelberg

2 × 2 games (such as the Prisoner’s Dilemma) are economic games for studying cooperation and social decision-making. Linearly-additive decomposed games are variants of 2 × 2 games that can change the framing of the game and thereby provide researchers with additional flexibility for measuring preferences and social cognition that would not be possi...

Detecting unusual auditory stimuli is crucial for discovering potential threat. Locus coeruleus (LC), which coordinates attention, and amygdala, which is implicated in resource prioritization, both respond to deviant sounds. Evidence concerning their interaction, however, is sparse. Seeking to elucidate if human amygdala affects estimated LC activi...

Social deficits are among the core and most striking psychiatric symptoms, present in most psychiatric disorders. Here, we introduce a novel social learning framework, which consists of neuro-computational models that combine reinforcement learning with various types of social knowledge structures. We outline how this social learning framework can...

Decisions in social dilemmas lead to outcomes for oneself and others. These outcomes can be gains or losses, yet we lack a full understanding of how people’s decisions depend on which outcomes are above or below zero. We systematically varied whether the outcomes of social dilemmas (Prisoner’s Dilemma, Stag-Hunt, Chicken) were losses, gains, or com...

To navigate social interactions successfully, humans need to continuously learn about the personality traits of other people (e.g., how helpful or aggressive is the other person?). However, formal models that capture the complexities of social learning processes are currently lacking. In this study, we specify and test potential strategies that hum...

Social interactions are dynamic, context-dependent, and reciprocal events that influence prospective strategies and require constant practice and adaptation. This complexity of social interactions creates several research challenges. We propose a new framework encouraging future research to investigate not only individual differences in capacities...

Social decisions are influenced by a person’s social preferences. High psychopathy is often considered related to poor social decision making, but less is known about the relationship between psychopathy and social preferences. In this study, we used a battery of economic games to study social decision- making and social preferences in relation to...

Social interactions are dynamic, context-dependent, and reciprocal events that influence prospective strategies and require constant practice and adaptation. This complexity of social interactions creates several research challenges. We propose a new framework encouraging future research to investigate not only individual differences in capacities...

Slowing the spread of COVID-19 requires people to actively change their lives by following protective practices, such as physical distancing and disinfecting their hands. Perceptions about the personal risk of COVID-19 may affect compliance with these practices. In this study, we assessed risk perception and optimism about COVID-19 in a multination...

2*2 games, such as the Prisoner's Dilemma, are a common tool for studying cooperation and social decision-making. In experiments, 2*2 games are usually presented in matrix form, such that participants see only the possible outcomes. Some 2*2 games can be decomposed into payoffs for self and other, such that participants see the direct consequences...

Learning to be safe is central for adaptive behaviour when threats are no longer present. Detecting the absence of an expected threat is key for threat extinction learning and an essential process for the behavioural treatment of anxiety related disorders. One possible mechanism underlying extinction learning is a dopaminergic mismatch signal that...

Humans hold social motives that are expressed in social preferences and influence how they evaluate and share payoffs. Established models in psychology and economics quantify social preferences such as general social value orientation, which captures people’s tendency to be prosocial or individualistic. Prosocials further differ by how much they ma...

Background The research domain criteria (RDoC) domain of negative valence systems can be used to subsume long established and recently developed research approaches, which build upon theoretical knowledge and clinical practice of various psychiatric disorders.Objective This article outlines how the five constructs within the RDoC domain of negative...

To navigate social interactions successfully, humans need to continuously learn about the personality traits of other people (e.g., how helpful or aggressive is the other person?). However, formal models that capture such complex social learning processes are currently lacking. In this study, we specified and tested potential strategies that humans...

Imagine that you meet someone new. You may wonder what they like, for example how much do they like baseball? You then get their feedback, which helps you to predict how much they like something similar, like basketball. We tested how teens and adults decide what others like and dislike and how they learn about others through feedback. This learnin...

Learning to be safe is central for adaptive behaviour when threats are no longer present. Detecting the absence of an expected threat is key for threat extinction learning and an essential process for the behavioural treatment of anxiety related disorders. One possible mechanism underlying extinction learning is a dopaminergic mismatch signal that...

Background Many of our efforts in social interactions are dedicated to learning about others. Adolescents with autism have core deficits in social learning, but a mechanistic understanding of these deficits and how they relate to neural development is lacking. The current study aimed to specify how adolescents with and with autism represent and acq...

Slowing the spread of COVID-19 requires people to actively change their lives and follow best practices for social distancing and hygiene. On 16.03.2020, we tested individuals’ beliefs about infection probabilities and abilities to practice social distancing in UK, USA and Germany. Given the rapidly evolving situation, we report here initial analys...

Background Many of our efforts in social interactions are dedicated to learning about others. Adolescents with autism have core deficits in social learning, but a mechanistic understanding of these deficits and how they relate to neural development is lacking. The current study aimed to specify how adolescents with and with autism represent and acq...

Jointly minimizing multiple threats over extended time horizons enhances survival. Consequently, many tests of approach–avoidance conflicts incorporate multiple threats for probing corollaries of animal and human anxiety. To facilitate computations necessary for threat minimization, the human brain may concurrently harness multiple decision policie...

Psychologists often use peripheral physiological measures to infer a psychological variable. It is desirable to make this inverse inference in the most precise way, ideally standardized across research laboratories. In recent years, psychophysiological modeling has emerged as a method that rests on statistical techniques to invert mathematically fo...

Learning to predict threat from environmental cues is a fundamental skill in changing environments. This aversive learning process is exemplified by Pavlovian threat conditioning. Despite a plethora of studies on the neural mechanisms supporting the formation of associations between neutral and aversive events, our computational understanding of th...

Mean model estimates, over 100 simulated CS+/- and reinforcement sequences. (PDF)

Results of LME fitting for SCR and PSR for the three experiments. (PDF)

Valproate is an anticonvulsant drug with strong preclinical evidence for reducing anxiety behaviour in rodents but no clear clinical evidence. To motivate clinical trials, we here investigate the use of valproate in a translational human model of anxiety behaviour. In a double-blind, randomised, placebo-controlled trial, n = 118 healthy participant...

Although emotional reactivity to social rejection has been examined in patients with borderline personality disorder (BPD) in several studies, the effects of other aspects of social feedback, such as evaluation of one’s opinions that concern self-esteem, have not been addressed yet. The objective of this study was to examine emotional responses of...

Optimistic estimates about the personal future constitute one of the best-described and most-debated decision biases related to emotion. Nevertheless, it has been difficult to isolate manipulations that reduce optimistic estimates. Eliciting estimates in a foreign language is a promising candidate manipulation because foreign language use alters de...

Decision-making biases, in particular the framing effect, can be altered in foreign language settings (foreign language effect) and following switching between languages (the language switching effect on framing). Recently, it has been suggested that the framing effect is only affected by foreign language use if the task is presented in a rich text...

Optimal decisions across extended time horizons require value calculations over multiple probabilistic future states. Humans may circumvent such complex computations by resorting to easy-to-compute heuristics that approximate optimal solutions. To probe the potential interplay between heuristic and optimal computations, we develop a novel sequentia...

As adolescents transition to the complex world of adults, optimizing predictions about others’ preferences becomes vital for successful social interactions. Mounting evidence suggests that these social learning processes are affected by ongoing brain development across adolescence. A mechanistic understanding of how adolescents optimize social pred...

How can apparent decision biases, such as the framing effect, be reduced? Intriguing findings within recent years indicate that foreign language settings reduce framing effects, which has been explained in terms of deeper cognitive processing. Because hard-to-read fonts have been argued to trigger deeper cognitive processing, so-called cognitive di...

During fear conditioning, pupil size responses dissociate between conditioned stimuli that are contingently paired (CS+) with an aversive unconditioned stimulus, and those that are unpaired (CS-). Current approaches to assess fear learning from pupil responses rely on ad hoc specifications. Here, we sought to develop a psychophysiological model (Ps...

Background: Rodent approach-avoidance conflict tests are common preclinical models of human anxiety disorder. Their translational validity mainly rests on the observation that anxiolytic drugs reduce rodent anxiety-like behavior. Here, we capitalized on a recently developed approach-avoidance conflict computer game to investigate the impact of ben...

In an elegant model-based fMRI study, Leong et al. (2017) demonstrate how attention and learning interact to facilitate value-based decision-making. They combine computational modeling with empirical measures of attentional selection derived from eye-tracking data and multivariate pattern analyses.

During fear conditioning, pupil size responses dissociate between conditioned stimuli that are contingently paired (CS+) with an aversive unconditioned stimulus, and those that are unpaired (CS-). Current approaches to assess fear learning from pupil responses rely on ad hoc specifications. Here, we sought to develop a psychophysiological model (Ps...

Borderline Personality Disorder (BPD) is associated with negative self-images. However, it has remained underexplored whether BPD patients hold negative views of their personal future. When receiving information about possible future live events, healthy participants tend to update their estimates more toward desirable than toward undesirable infor...

Pupil size is often used to infer central processes, including attention, memory, and emotion. Recent research has spotlighted its relation to behavioral variables from decision-making models and to neural variables such as locus coeruleus activity and cortical oscillations. As yet, a unified and principled approach for analyzing pupil responses is...

A considerable literature on attribution theory has shown that healthy individuals exhibit a positivity bias when inferring the causes of evaluative feedback on their performance. They tend to attribute positive feedback internally (e.g., to their own abilities) but negative feedback externally (e.g., to environmental factors). However, all empiric...

Stimuli details. Description of the video items used in the task. (DOCX)

Background: Patients with borderline personality disorder (BPD) show negative and unstable self- and other-evaluations compared to healthy individuals. It is unclear, however, how they process self- and other-relevant social feedback. We have previously demonstrated a positive updating bias in healthy individuals: When receiving social feedback on...

Recent studies reported reductions of well-established biases in decision making under risk, such as the framing effect, during foreign language (FL) use. These modulations were attributed to the use of FL itself, which putatively entails an increase in emotional distance. A reduced framing effect in this setting, however, might also result from en...

Living organisms need to maintain energetic homeostasis. For many species, this implies taking actions with delayed consequences. For example, humans may have to decide between foraging for high-calorie but hard-to-get, and low-calorie but easy-to-get food, under threat of starvation. Homeostatic principles prescribe decisions that maximize the pro...

Recent evidence suggests that a state of good mental health is associated with biased processing of information that supports a positively skewed view of the future. Depression, on the other hand, is associated with unbiased processing of such information. Here, we use brain imaging in conjunction with a belief update task administered to clinicall...

Talking about emotion and sharing emotional experiences is a key component of human interaction. Specifically, individuals often consider the reactions of other people when evaluating the meaning and impact of an emotional stimulus. It has not yet been investigated, however, how emotional arousal ratings and physiological responses elicited by affe...

Cultural differences are generally explained by how people see themselves in relation to social interaction partners. While Western culture emphasizes independence, East Asian culture emphasizes interdependence. Despite this focus on social interactions, it remains elusive how people from different cultures process feedback on their own (and on oth...

Background When challenged with information about the future, healthy participants show an optimistically biased updating pattern, taking desirable information more into account than undesirable information. However, it is unknown how patients suffering from major depressive disorder (MDD), who express pervasive pessimistic beliefs, update their be...

Key points Dopamine D 1 receptors activate the cAMP/protein kinase A (PKA) pathway in both cortex and striatum, with different types of signalling enzymes being involved in cAMP/PKA signal integration. We investigated the functional implications of such differences. Biosensor imaging in mouse brain slice preparations revealed that the cAMP/PKA sign...

Receiving social feedback such as praise or blame for one's character traits is a key component of everyday human interactions. It has been proposed that humans are positively biased when integrating social feedback into their self-concept. However, a mechanistic description of how humans process self-relevant feedback is lacking. Here, participant...

People often use expert advice when making decisions in our society, but how we are influenced by this advice has yet to be understood. To address this, using functional magnetic resonance imaging, we provided expert and novice advice to participants during an estimation task. Participants reported that they valued expert advice more than novice ad...

Humans form beliefs asymmetrically; we tend to discount bad news but embrace good news. This reduced impact of unfavorable information on belief updating may have important societal implications, including the generation of financial market bubbles, ill preparedness in the face of natural disasters, and overly aggressive medical decisions. Here, we...

When predicting financial profits, relationship outcomes, longevity, or professional success, people habitually underestimate the likelihood of future negative events. This well-known bias, termed unrealistic optimism, is observed across age, culture, and species, and has a significant societal impact on domains ranging from financial markets to he...

Unrealistic optimism is a pervasive human trait that influences domains ranging from personal relationships to politics and finance. How people maintain unrealistic optimism, despite frequently encountering information that challenges those biased beliefs, is unknown. We examined this question and found a marked asymmetry in belief updating. Partic...