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1.
Sci Rep ; 14(1): 8739, 2024 04 16.
Article in English | MEDLINE | ID: mdl-38627572

ABSTRACT

Inspired by recent findings in the visual domain, we investigated whether the stimulus-evoked pupil dilation reflects temporal statistical regularities in sequences of auditory stimuli. We conducted two preregistered pupillometry experiments (experiment 1, n = 30, 21 females; experiment 2, n = 31, 22 females). In both experiments, human participants listened to sequences of spoken vowels in two conditions. In the first condition, the stimuli were presented in a random order and, in the second condition, the same stimuli were presented in a sequence structured in pairs. The second experiment replicated the first experiment with a modified timing and number of stimuli presented and without participants being informed about any sequence structure. The sound-evoked pupil dilation during a subsequent familiarity task indicated that participants learned the auditory vowel pairs of the structured condition. However, pupil diameter during the structured sequence did not differ according to the statistical regularity of the pair structure. This contrasts with similar visual studies, emphasizing the susceptibility of pupil effects during statistically structured sequences to experimental design settings in the auditory domain. In sum, our findings suggest that pupil diameter may serve as an indicator of sound pair familiarity but does not invariably respond to task-irrelevant transition probabilities of auditory sequences.


Subject(s)
Pupil , Sound , Female , Humans , Pupil/physiology , Recognition, Psychology , Auditory Perception/physiology
2.
Sci Rep ; 14(1): 8344, 2024 04 09.
Article in English | MEDLINE | ID: mdl-38594328

ABSTRACT

Social decisions are influenced by a person's social preferences. High psychopathy is defined by antisocial behaviour, but the relationship between psychopathy and social preferences remains unclear. In this study, we used a battery of economic games to study social decision-making and social preferences in relation to psychopathy in a sample of 35 male prison inmates, who were arrested for sexual and severe violent offenses (mean age = 39 years). We found no evidence for a relationship between social preferences (measured with the Dictator and Ultimatum Games, Social Value Orientation, and one-shot 2 × 2 games) and psychopathy (measured by the overall Hare Psychopathy Checklist-Revised score and both factors). These results are surprising but also difficult to interpret due to the small sample size. Our results contribute to the ongoing debate about psychopathy and social decision-making by providing crucial data that can be combined with future datasets to reach large sample sizes that can provide a more nuanced understanding about the relationship between psychopathy and social preferences.


Subject(s)
Antisocial Personality Disorder , Prisoners , Humans , Male , Adult , Antisocial Personality Disorder/diagnosis , Pilot Projects , Aggression , Social Behavior Disorders
3.
Nervenarzt ; 95(5): 467-473, 2024 May.
Article in German | MEDLINE | ID: mdl-38668756

ABSTRACT

BACKGROUND: Early career scientists (ECS) are agents of change and driving forces in the promotion of mental health. The German Center for Mental Health (DZPG) is a powerful initiative to guide and support careers in the field of mental health. OBJECTIVE: The DZPG aims to make investments to educate, engage, excite, and empower ECS in an interdisciplinary and interinstitutional scientific community. STRUCTURES, TOPICS AND INITIATIVES: To achieve this, the ECS Board at the DZPG plays a central role and consists of 18 elected ECS representatives. The ECS culture gives members the right of voice and embraces bottom-to-top ideas and acknowledges autonomy and co-determination. The DZPG academy was developed to facilitate communication and networking and encourage collaboration among ECS members. The DZPG also navigates several key issues, such as equality, diversity, inclusion, family friendliness and work-life balance, which are essential for a functioning research landscape. The DZPG also extends opportunities to ECS to develop skills and competencies that are essential for contemporary ECS. It complements nationwide support for ECS with funding opportunities, mental health support at work, careers advice and guidance activities. Importantly, the ECS Board is committed to patient and public involvement and engagement, scientific communication and knowledge transfer to multiple settings. CONCLUSION: The DZPG will contribute to fostering ECS training programs for student and academic exchanges, collaborative research, and pooling of resources to acquire grants and scholarships. It will also support the establishment of hubs for ECS networks and promote the expansion of international competence of ECS in Germany.


Subject(s)
Career Choice , Germany , Humans , Mental Health , Intersectoral Collaboration , Organizational Objectives , Research Personnel , Interinstitutional Relations
4.
Eur J Neurosci ; 59(10): 2686-2701, 2024 May.
Article in English | MEDLINE | ID: mdl-38469976

ABSTRACT

In everyday perception, we combine incoming sensory information with prior expectations. Expectations can be induced by cues that indicate the probability of following sensory events. The information provided by cues may differ and hence lead to different levels of uncertainty about which event will follow. In this experiment, we employed pupillometry to investigate whether the pupil dilation response to visual cues varies depending on the level of cue-associated uncertainty about a following auditory outcome. Also, we tested whether the pupil dilation response reflects the amount of surprise about the subsequently presented auditory stimulus. In each trial, participants were presented with a visual cue (face image) which was followed by an auditory outcome (spoken vowel). After the face cue, participants had to indicate by keypress which of three auditory vowels they expected to hear next. We manipulated the cue-associated uncertainty by varying the probabilistic cue-outcome contingencies: One face was most likely followed by one specific vowel (low cue uncertainty), another face was equally likely followed by either of two vowels (intermediate cue uncertainty) and the third face was followed by all three vowels (high cue uncertainty). Our results suggest that pupil dilation in response to task-relevant cues depends on the associated uncertainty, but only for large differences in the cue-associated uncertainty. Additionally, in response to the auditory outcomes, the pupil dilation scaled negatively with the cue-dependent probabilities, likely signalling the amount of surprise.


Subject(s)
Cues , Pupil , Humans , Male , Female , Pupil/physiology , Uncertainty , Adult , Young Adult , Auditory Perception/physiology , Visual Perception/physiology , Speech Perception/physiology , Photic Stimulation/methods , Acoustic Stimulation/methods
5.
Autism ; : 13623613231203306, 2023 Oct 26.
Article in English | MEDLINE | ID: mdl-37882152

ABSTRACT

LAY ABSTRACT: In the COVID-19 pandemic, wearing face masks became mandatory to prevent the spread of the virus. However, they restrict the ability to recognize emotions to the upper part of the face. Since individuals with autism spectrum condition often tend to look at the lower half of the face, they may be particularly restricted in emotion recognition by people wearing masks, since they are now forced to look at the upper half of the face. The current study compared the recognition of facially expressed emotions between individuals with and without autism spectrum condition. Each photo was shown in three types, once uncovered, once with face mask, and once with sunglasses. Our results revealed a reduction in accuracy of individuals with autism spectrum condition at recognizing emotions in all three stimulus types and exhibited more difficulties distinguishing anger, fear, pride, and embarrassment. During the emotion recognition task, there was no difference in which facial areas the groups looked at. We did not find evidence that the disadvantages of individuals with autism spectrum condition in emotion recognition were due to looking at different areas of the face.

6.
Sci Rep ; 13(1): 14550, 2023 09 04.
Article in English | MEDLINE | ID: mdl-37667022

ABSTRACT

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 activity during this process, we recorded pupillary responses during an auditory oddball and an illuminance change task, in a female with bilateral amygdala lesions (BG) and in n = 23 matched controls. Neural input in response to oddballs was estimated via pupil dilation, a reported proxy of LC activity, harnessing a linear-time invariant system and individual pupillary dilation response function (IRF) inferred from illuminance responses. While oddball recognition remained intact, estimated LC input for BG was compacted to an impulse rather than the prolonged waveform seen in healthy controls. This impulse had the earliest response mean and highest kurtosis in the sample. As a secondary finding, BG showed enhanced early pupillary constriction to darkness. These findings suggest that LC-amygdala communication is required to sustain LC activity in response to anomalous sounds. Our results provide further evidence for amygdala involvement in processing deviant sound targets, although it is not required for their behavioral recognition.


Subject(s)
Amygdala , Locus Coeruleus , Humans , Female , Recognition, Psychology , Acceleration , Communication
7.
Neurosci Biobehav Rev ; 149: 105181, 2023 06.
Article in English | MEDLINE | ID: mdl-37062494

ABSTRACT

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 help specify and quantify social psychopathology across disorders and provide an overview of the brain regions that may be involved in this type of social learning. We highlight how this framework can specify commonalities and differences in the social psychopathology of individuals with autism spectrum disorder (ASD), personality disorders (PD), and major depressive disorder (MDD) and improve treatments on an individual basis. We conjecture that individuals with psychiatric disorders rely on rigid social knowledge representations when learning about others, albeit the nature of their rigidity and the behavioral consequences can greatly differ. While non-clinical cohorts tend to efficiently adapt social knowledge representations to relevant environmental constraints, psychiatric cohorts may rigidly stick to their preconceived notions or overly coarse knowledge representations during learning.


Subject(s)
Autism Spectrum Disorder , Depressive Disorder, Major , Mental Disorders , Social Learning , Humans , Autism Spectrum Disorder/psychology , Depressive Disorder, Major/therapy , Mental Disorders/therapy , Brain
8.
Clin Psychol Rev ; 98: 102204, 2022 12.
Article in English | MEDLINE | ID: mdl-36216722

ABSTRACT

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 relevant for social functioning and their underlying mechanisms, but also the flexibility to adapt or update one's social abilities. We suggest three key capacities relevant for social functioning: (1) social perception, (2) sharing emotions or empathizing, and (3) mentalizing. We elaborate on how adaptations in these capacities may be investigated on behavioral and neural levels. Research on these flexible adaptations of one's social behavior is needed to specify how humans actually "learn to be social". Learning to adapt implies plasticity of the relevant brain networks involved in the underlying social processes, indicating that social abilities are malleable for different contexts. To quantify such measures, researchers need to find ways to investigate learning through dynamic changes in adaptable social paradigms and examine several factors influencing social functioning within the three aformentioned social key capacities. This framework furthers insight concerning individual differences, provides a holistic approach to social functioning, and may improve interventions for ameliorating social abilities in patients.


Subject(s)
Mental Health , Social Adjustment , Humans , Prospective Studies , Social Perception , Social Behavior
9.
Nat Commun ; 13(1): 6205, 2022 10 20.
Article in English | MEDLINE | ID: mdl-36266284

ABSTRACT

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 humans can employ for learning about others. Standard Rescorla-Wagner (RW) learning models only capture parts of the learning process because they neglect inherent knowledge structures and omit previously acquired knowledge. We therefore formalize two social knowledge structures and implement them in hybrid RW models to test their usefulness across multiple social learning tasks. We name these concepts granularity (knowledge structures about personality traits that can be utilized at different levels of detail during learning) and reference points (previous knowledge formalized into representations of average people within a social group). In five behavioural experiments, results from model comparisons and statistical analyses indicate that participants efficiently combine the concepts of granularity and reference points-with the specific combinations in models depending on the people and traits that participants learned about. Overall, our experiments demonstrate that variants of RW algorithms, which incorporate social knowledge structures, describe crucial aspects of the dynamics at play when people interact with each other.


Subject(s)
Algorithms , Learning , Humans , Computer Simulation
10.
R Soc Open Sci ; 8(11): 210904, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34804569

ABSTRACT

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 multinational (UK, USA and Germany), longitudinal design during the early stages of the pandemic (16 March 2020; 1 April 2020; 20 May 2020). Our main findings are that (i) people showed a comparative optimism bias about getting infected and infecting others, but not for getting severe symptoms, (ii) this optimism bias did not change over time, (iii) optimism bias seemed to relate to perceived level of control over the action, (iv) risk perception was linked to publicly available information about the disorder, (v) people reported adhering closely to protective measures but these measures did not seem to be related to risk perception, and (vi) risk perception was related to questions about stress and anxiety. In additional cross-sectional samples, we replicated our most important findings. Our open and partly preregistered results provide detailed descriptions of risk perceptions and optimistic beliefs during the early stages of the COVID-19 pandemic in three Western countries.

11.
Neuropsychologia ; 162: 108016, 2021 11 12.
Article in English | MEDLINE | ID: mdl-34499958

ABSTRACT

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 maximize joint gains or minimize inequality. Functional neuroimaging studies have linked increased amygdala activity in prosocials to payoff inequality between self and other. However, it is unclear whether amygdala lesions alter social motives. We used two tasks to test a patient with selective bilateral amygdala lesions and three healthy samples (a priori matched control sample N = 20, online sample N = 603, student sample N = 40), which allowed us to assess and model social motives across a relatively large number of participants. In a social value orientation task, the patient was categorized as prosocial and her social value orientation score did not differ from healthy participants. Importantly, the patient differed in prosocial motivation by maximizing joint gains rather than minimizing payoff inequality. In a joint payoff evaluation task, Bayesian model comparisons revealed that participants' evaluations were best described by models, which link participants' evaluations to the payoff magnitude and to inequality. Overall, amygdala lesions did not seem to alter general social value orientation but shifted prosocial motivation toward maximizing joint gains.


Subject(s)
Motivation , Social Values , Amygdala/diagnostic imaging , Bayes Theorem , Female , Humans , Social Behavior
12.
Elife ; 102021 09 02.
Article in English | MEDLINE | ID: mdl-34473055

ABSTRACT

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 encodes the absence of an expected threat. Here we show that such a dopamine-related pathway underlies extinction learning in humans. Dopaminergic enhancement via administration of L-DOPA (vs. Placebo) was associated with reduced retention of differential psychophysiological threat responses at later test, which was mediated by activity in the ventromedial prefrontal cortex that was specific to extinction learning. L-DOPA administration enhanced signals at the time-point of an expected, but omitted threat in extinction learning within the nucleus accumbens, which were functionally coupled with the ventral tegmental area and the amygdala. Computational modelling of threat expectancies further revealed prediction error encoding in nucleus accumbens that was reduced when L-DOPA was administered. Our results thereby provide evidence that extinction learning is influenced by L-DOPA and provide a mechanistic perspective to augment extinction learning by dopaminergic enhancement in humans.


Subject(s)
Brain , Extinction, Psychological/drug effects , Fear/drug effects , Levodopa/pharmacology , Adult , Brain/drug effects , Brain/physiology , Humans , Male , Nucleus Accumbens/drug effects , Nucleus Accumbens/physiology , Prefrontal Cortex/drug effects , Prefrontal Cortex/physiology , Ventral Tegmental Area/drug effects , Ventral Tegmental Area/physiology , Young Adult
13.
Nervenarzt ; 92(9): 868-877, 2021 Sep.
Article in German | MEDLINE | ID: mdl-34351434

ABSTRACT

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 valence systems can contribute to integrating empirical studies into a coherent and differentiated biopsychosocial model. MATERIAL AND METHODS: This is a qualitative review article that summarizes empirical results and discusses new developments on the basis of exemplary studies and selected reviews. RESULTS AND DISCUSSION: The RDoC domain of negative valence systems differentiates in three constructs the time horizon, in which persons need to adequately react to (1) acute, (2) potential, and (3) sustained threats elicited by negative stimuli or situations. These three constructs can be outlined relatively well with specific experimental paradigms and neuronal circuits. Two further constructs focus on the negative consequences of (4) losses and (5) frustrative non-rewards. The former seems to be currently relatively diffusely defined whereas the latter is clearly circumscribed by its relation to specific forms of aggression. Behavioral, physiological, and neuronal reactions to acute and potential threats can be well compared between humans and animals and can be specified with the help of mathematical models. These models can contribute to a better understanding of how healthy and diseased persons process negative stimuli or situations.


Subject(s)
Mental Disorders , Aggression , Animals , Humans , Mental Disorders/diagnosis
14.
Article in English | MEDLINE | ID: mdl-32952091

ABSTRACT

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 present study aimed to specify how adolescents with and without autism represent and acquire social knowledge and how these processes are implemented in neural activity. METHODS: Typically developing adolescents (n = 26) and adolescents with autism spectrum disorder (ASD) (n = 20) rated in the magnetic resonance scanner how much 3 peers liked a variety of items and received trial-by-trial feedback about the peers' actual preference ratings. In a separate study, we established the preferences of a new sample of adolescents (N = 99), used to examine population preference structures. Using computational models, we tested whether participants in the magnetic resonance study relied on preference structures during learning and how model predictions were implemented in brain activity. RESULTS: Typically developing adolescents relied on average population preferences and prediction error updating. Importantly, prediction error updating was scaled by the similarity between items. In contrast, preferences of adolescents with ASD were best described by a No-Learning model that relied only on the participant's own preferences for each item. Model predictions were encoded in neural activity. Typically developing adolescents encoded prediction errors in the putamen, and adolescents with ASD showed greater encoding of own preferences in the angular gyrus. CONCLUSIONS: We specified how adolescents represent and update social knowledge during learning. Our findings indicate that adolescents with ASD rely only on their own preferences when making social inferences.


Subject(s)
Autism Spectrum Disorder , Autistic Disorder , Adolescent , Emotions , Humans , Learning , Magnetic Resonance Imaging
15.
Nat Hum Behav ; 3(7): 733-745, 2019 07.
Article in English | MEDLINE | ID: mdl-31110338

ABSTRACT

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 policies and associated neural controllers, but it is unclear which. We combine a task that mimics foraging under predation with behavioural modelling and functional neuroimaging. Human choices rely on immediate predator probability-a myopic heuristic policy-and on the optimal policy, which integrates all relevant variables. Predator probability relates positively and the associated choice uncertainty relates negatively to activations in the anterior hippocampus, amygdala and dorsolateral prefrontal cortex. The optimal policy is positively associated with dorsomedial prefrontal cortex activity. We thus provide a decision-theoretic outlook on the role of the human hippocampus, amygdala and prefrontal cortex in resolving approach-avoidance conflicts relevant for anxiety and integral for survival.


Subject(s)
Amygdala/diagnostic imaging , Anxiety/physiopathology , Avoidance Learning/physiology , Choice Behavior/physiology , Decision Making/physiology , Hippocampus/diagnostic imaging , Prefrontal Cortex/diagnostic imaging , Adult , Amygdala/physiology , Appetitive Behavior , Female , Functional Neuroimaging , Hippocampus/physiology , Humans , Magnetic Resonance Imaging , Male , Prefrontal Cortex/physiology , Young Adult
16.
Q J Exp Psychol (Hove) ; 72(1): 52-59, 2019 Jan.
Article in English | MEDLINE | ID: mdl-29595362

ABSTRACT

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 textual form. Here, we assess whether an elaborate verbal task is also a prerequisite for the language switching effect on framing. We employed a financial gambling task that induces a robust framing effect but is less verbal than the classical framing paradigms (e.g., the Asian disease problem). We conducted an online experiment ( n = 485), where we orthogonally manipulated language use and language switching between trials. The results showed no effects of foreign language use or language switching throughout the experiment. This online result was confirmed in a laboratory experiment ( n = 27). Overall, we find that language switching does not reduce the framing effect in a paradigm with little verbal content and thus that language switching effects seem contingent on the amount of verbal processing required.


Subject(s)
Decision Making , Executive Function/physiology , Language , Morals , Adult , Female , Games, Experimental , Humans , Interpersonal Relations , Logistic Models , Male , Middle Aged , Multilingualism , Psychological Tests , Reaction Time , Young Adult
17.
Q J Exp Psychol (Hove) ; 72(1): 60-75, 2019 Jan.
Article in English | MEDLINE | ID: mdl-29741451

ABSTRACT

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 decision biases in scenarios with emotional components. Consequently, we tested whether foreign language use reduces optimistic estimates. In a laboratory experiment, participants ( n = 45) estimated their probability of experiencing life events either in their native language or a foreign language, in which they were highly proficient. We found no differences in these estimates or in the updating of these estimates after receiving feedback about the population baseline probability. Importantly, three online experiments with large sample sizes ( ns = 706, 530, and 473) showed that using a foreign language with low proficiency reduced comparative optimism. Participants in the online experiments had diverse proficiency levels and were matched on a variety of control metrics. Fine-grained analyses indicated that low proficiency weakens the coupling between probability estimates and rated arousal. Overall, our findings suggest that an important decision bias can be reduced when using a foreign language with low proficiency.


Subject(s)
Decision Making/physiology , Multilingualism , Optimism/psychology , Self Concept , Verbal Behavior/physiology , Adult , Arousal , Bias , Female , Humans , Interpersonal Relations , Judgment , Male , Online Systems , Probability , Young Adult
18.
Psychophysiology ; 55(11): e13214, 2018 11.
Article in English | MEDLINE | ID: mdl-30175471

ABSTRACT

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 formulated forward models (psychophysiological models, PsPMs). These PsPMs are based on psychophysiological knowledge and optimized with respect to the precision of the inference. Building on established experimental manipulations, known to create different values of a psychological variable, they can be benchmarked in terms of their sensitivity (e.g., effect size) to recover these values-we have termed this predictive validity. In this review, we introduce the problem of inverse inference and psychophysiological modeling as a solution. We present background and application for all peripheral measures for which PsPMs have been developed: skin conductance, heart period, respiratory measures, pupil size, and startle eyeblink. Many of these PsPMs are task invariant, implemented in open-source software, and can be used off the shelf for a wide range of experiments. Psychophysiological modeling thus appears as a potentially powerful method to infer psychological variables.


Subject(s)
Autonomic Nervous System , Models, Theoretical , Psychophysiology/methods , Humans , Psychophysiology/trends
19.
PLoS Comput Biol ; 14(8): e1006243, 2018 08.
Article in English | MEDLINE | ID: mdl-30169519

ABSTRACT

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 this process is fragmented. Importantly, different computational models give rise to different and partly opposing predictions for the trial-by-trial dynamics of learning, for example expressed in the activity of the autonomic nervous system (ANS). Here, we investigate human ANS responses to conditioned stimuli during Pavlovian fear conditioning. To obtain precise, trial-by-trial, single-subject estimates of ANS responses, we build on a statistical framework for psychophysiological modelling. We then consider previously proposed non-probabilistic models, a simple probabilistic model, and non-learning models, as well as different observation functions to link learning models with ANS activity. Across three experiments, and both for skin conductance (SCR) and pupil size responses (PSR), a probabilistic learning model best explains ANS responses. Notably, SCR and PSR reflect different quantities of the same model: SCR track a mixture of expected outcome and uncertainty, while PSR track expected outcome alone. In summary, by combining psychophysiological modelling with computational learning theory, we provide systematic evidence that the formation and maintenance of Pavlovian threat predictions in humans may rely on probabilistic inference and includes estimation of uncertainty. This could inform theories of neural implementation of aversive learning.


Subject(s)
Conditioning, Classical/physiology , Learning/physiology , Probability Learning , Autonomic Nervous System/physiology , Cues , Fear/physiology , Humans , Machine Learning , Models, Theoretical
20.
Transl Psychiatry ; 8(1): 157, 2018 08 16.
Article in English | MEDLINE | ID: mdl-30115911

ABSTRACT

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 participants played a previously validated approach/avoidance conflict computer game to measure anxiety-like behaviour, while under 400 mg valproate, under 200 mg of the established anxiolytic/anticonvulsant pregabalin, or under placebo. Saccadic peak velocity and subjective ratings were assessed to control for drug-induced sedation. Compared to placebo, valproate and pregabaline were anxiolytic in the primary outcome, and several secondary outcomes. Bayesian model comparison decisively demonstrated no differences between the two drugs. Subjective and objective sedation was significantly more pronounced under pregabalin than valproate, but did not explain anxiolytic effects. We demonstrate acute anxiolytic properties of valproate in healthy humans. Both drugs have similar anxiolytic properties at the doses used. Valproate is less sedative than pregabalin. Our results suggest clinical trials on the use of valproate in anxiolytic treatment. More generally, we propose a strategy of screening drugs in human preclinical models that can directly be compared across species, such as the approach/avoidance conflict computer game used here. This approach could thus facilitate translational anxiety research.


Subject(s)
Anti-Anxiety Agents/administration & dosage , Anxiety/drug therapy , Pregabalin/administration & dosage , Valproic Acid/administration & dosage , Video Games/psychology , Adult , Bayes Theorem , Decision Making , Double-Blind Method , Female , Healthy Volunteers , Humans , Male , Saccades , Switzerland , Translational Research, Biomedical , Young Adult
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