Impact of online poker gambling on behavioural and neurophysiological responses to a virtual gambling task.

Online poker gambling (OPG) involves various executive control processes and emotion regulation. In this context, we hypothesized that online poker players, accustomed to handling virtual cards, would show high performance on computerized decision-making tasks such as the Iowa Gambling Task (IGT). Using press advertisements, we recruited a non-gambler group (NG; n = 20) and an OPG group (n = 22). All participants performed the IGT while their cerebral activity was recorded by electroencephalography. Compared with the OPG group, the NG group showed significantly better progression in the IGT in the last trials. Recording of brain activity revealed the appearance of a temporal map between 150 and 175 ms specific to the gain condition in both groups. A second map was observed at 215-295 ms specifically in the NG group, and the generators were identified in the occipital regions. This activity is indicative of a high level of visual awareness; thus, it reflects additional processing of visual information, which can be assumed to be induced by the lower exposure of the NGs to online card games. We hypothesize that the absence of this activity in the OPG group might be due to their online habituation to virtual environments.

Contribution of cosmetic ingredients and skin care textures to emotions.

OBJECTIVE: Emotions play an important role in consumers' perception of a sensory experience. The objective of this work was to investigate the ability of basic skin care formulas (i.e. without interference of odour, colour and packaging) and pillar ingredients (i.e. emollients and rheology modifiers) to elicit emotions. Another objective was to track, as claimed by neurocosmetics, the possible effect of formulas to trigger emotions from their direct biochemical effects on the skin. METHODS: Standard methodologies were mobilized, combining subjective and behavioural parameters (i.e. verbatim, prosody and gesture). Sense and Story methodology based on a collection of metaphoric verbatim was conducted after an induction phase. In addition, an experimental electrophysiological real-time visualization method was tried as a first experience in cosmetics. Finally, the ability of formulations with emotional benefits to modulate the release of neuropeptides by sensory neurons was evaluated on a 3D human model (epidermis co-cultured with sensory neurons). RESULTS: Skin care formulas were shown to play a role in emotional potential and the types of emotion generated, while changing one ingredient mostly acted on the intensity of the emotions. Verbatim provided contrasted answers depending on the protocol, highlighting the interest of non-verbal approaches to detect subtle effects. The in vitro model substantiated physiological effects of skin care formulas with emotional potential on human skin sensory neuron activity. CONCLUSION: Emotions were impacted by the change in ingredients and were better captured through non-verbal methods.

OBJECTIF: Les émotions jouent un rôle important dans la perception qu'ont les consommateurs d'une expérience sensorielle. L'objectif de ce travail était d'étudier la capacité de formules de soins pour la peau de base (c'est­à­dire sans interférence d'odeur, de couleur, d'emballage) et d' ingrédients essentiels (c'est­à­dire les émollients et les modificateurs de rhéologie) à susciter des émotions. Un autre objectif était de suivre, comme le prétendent les neurocosmétiques, l'effet possible des formules à déclencher des émotions à partir de leurs effets biochimiques directs sur la peau. MÉTHODES: Des méthodologies standards ont été mises en œuvre, combinant des paramètres subjectifs et comportementaux (c'est­à­dire verbatim, prosodie et gestuelle). La méthodologie Sense & Story basée sur un ensemble de verbatim métaphoriques a été mise en œuvre après une phase d'induction. En outre, une méthode expérimentale de visualisation électrophysiologique en temps réel a été testée comme première expérience dans le domaine des cosmétiques. Enfin, la capacité des formulations présentant des bénéfices émotionnels à moduler la libération de neuropeptides par les neurones sensoriels a été évaluée sur un modèle humain 3D (épiderme co­cultivé avec des neurones sensoriels). RÉSULTATS: Il a été démontré que les formules de soins pour la peau jouent un rôle dans le potentiel émotionnel et les types d'émotions générées, tandis que le changement d'un ingrédient agit principalement sur l'intensité des émotions. Le verbatim a fourni des réponses contrastées selon le protocole, soulignant l'intérêt des approches non verbales pour détecter les effets subtils. Le modèle in vitro a confirmé les effets physiologiques des formules de soins pour la peau ayant un potentiel émotionnel sur l'activité des neurones sensoriels de la peau humaine. CONCLUSION: Les émotions ont été affectées par le changement d'ingrédients et ont été mieux saisies par des méthodes non verbales.

Three simple steps to improve the interpretability of EEG-SVM studies.

Machine-learning systems that classify electroencephalography (EEG) data offer important perspectives for the diagnosis and prognosis of a wide variety of neurological and psychiatric conditions, but their clinical adoption remains low. We propose here that much of the difficulties translating EEG-machine-learning research to the clinic result from consistent inaccuracies in their technical reporting, which severely impair the interpretability of their often-high claims of performance. Taking example from a major class of machine-learning algorithms used in EEG research, the support-vector machine (SVM), we highlight three important aspects of model development (normalization, hyperparameter optimization, and cross-validation) and show that, while these three aspects can make or break the performance of the system, they are left entirely undocumented in a shockingly vast majority of the research literature. Providing a more systematic description of these aspects of model development constitute three simple steps to improve the interpretability of EEG-SVM research and, in fine, its clinical adoption.

Don't forget the lyrics! Spatiotemporal dynamics of neural mechanisms spontaneously evoked by gaps of silence in familiar and newly learned songs.

The vast majority of people experience musical imagery, the sensation of reliving a song in absence of any external stimulation. Internal perception of a song can be deliberate and effortful, but also may occur involuntarily and spontaneously. Moreover, musical imagery is also involuntarily used for automatically completing missing parts of music or lyrics from a familiar song. The aim of our study was to explore the onset of musical imagery dynamics that leads to the automatic completion of missing lyrics. High-density electroencephalography was used to record the cerebral activity of twenty healthy volunteers while they were passively listening to unfamiliar songs, very familiar songs, and songs previously listened to for two weeks. Silent gaps inserted into these songs elicited a series of neural activations encompassing perceptual, attentional and cognitive mechanisms (range 100-500ms). Familiarity and learning effects emerged as early as 100ms and lasted 400ms after silence occurred. Although participants reported more easily mentally imagining lyrics in familiar rather than passively learnt songs, the onset of neural mechanisms and the power spectrum underlying musical imagery were similar for both types of songs. This study offers new insights into the musical imagery dynamics evoked by gaps of silence and on the role of familiarity and learning processes in the generation of these dynamics. The automatic and effortless method presented here is a potentially useful tool to understand failure in the familiarity and learning processes of pathological populations.

Neural Correlate of Anterograde Amnesia in Wernicke-Korsakoff Syndrome.

The neural correlate of anterograde amnesia in Wernicke-Korsakoff syndrome (WKS) is still debated. While the capacity to learn new information has been associated with integrity of the medial temporal lobe (MTL), previous studies indicated that the WKS is associated with diencephalic lesions, mainly in the mammillary bodies and anterior or dorsomedial thalamic nuclei. The present study tested the hypothesis that amnesia in WKS is associated with a disrupted neural circuit between diencephalic and hippocampal structures. High-density evoked potentials were recorded in four severely amnesic patients with chronic WKS, in five patients with chronic alcoholism without WKS, and in ten age matched controls. Participants performed a continuous recognition task of pictures previously shown to induce a left medial temporal lobe dependent positive potential between 250 and 350 ms. In addition, the integrity of the fornix was assessed using diffusion tensor imaging (DTI). WKS, but not alcoholic patients without WKS, showed absence of the early, left MTL dependent positive potential following immediate picture repetitions. DTI indicated disruption of the fornix, which connects diencephalic and hippocampal structures. The findings support an interpretation of anterograde amnesia in WKS as a consequence of a disconnection between diencephalic and MTL structures with deficient contribution of the MTL to rapid consolidation.

State of the art and future directions for measuring event-related potentials during cycling exercise: a systematic review.

Intro: Electroencephalography (EEG) is a technique for measuring brain activity that is widely used in neuroscience research. Event-related potentials (ERPs) in the EEG make it possible to study sensory and cognitive processes in the brain. Previous reports have shown that aerobic exercise can have an impact on components of ERPs such as amplitude and latency. However, they focused on the measurement of ERPs after exercise. Objectives: The aim of this systematic review was to investigate the feasibility of measuring ERPs during cycling, and to assess the impact of cycling on ERPs during cycling. Methods: We followed the PRISMA guidelines for new systematic reviews. To be eligible, studies had to include healthy adults and measure ERPs during cycling. All articles were found using Google Scholar and by searching references. Data extracted from the studies included: objectives of ERP studies, ERP paradigm, EEG system, study population data, exercise characteristics (duration, intensity, pedaling cadence), and ERP and behavioral outcomes. The Cochrane Risk of Bias 2 tool was used to assess study bias. Results: Twenty studies were selected. The effect of cycling on ERPs was mainly based on a comparison of P3 wave amplitude between cycling and resting states, using an attentional task. The ERP paradigm most often used was the auditory oddball task. Exercise characteristics and study methods varied considerably. Discussion: It is possible to measure ERPs during cycling under conditions that are likely to introduce more artifacts, including a 3-h athletic exercise session and cycling outdoors. Secondly, no assessment of the effect of cycling on ERPs was possible, because the methods differed too widely between studies. In addition, the theories proposed to explain the results sometimes seemed to contradict each other. Although most studies reported significant results, the direction of the effects was inconsistent. Finally, we suggest some areas for improvement for future studies on the subject.

Adherence to rehabilitation and home exercise after myocardial infarction: a qualitative study of expectations, barriers and drivers.

BACKGROUND: Cardiac rehabilitation is a key component of secondary prevention, but uptake is often low, and motivation to pursue exercise and lifestyle changes may be lacking in patients who have suffered from acute myocardial infarction (AMI). We explored the intentions of patients hospitalized for AMI regarding attendance at cardiac rehabilitation and the future pursuit of regular physical exercise at home. METHODS: We performed a qualitative study using semi-structured interviews. Eligible patients were those hospitalized for AMI in the cardiology unit of a large university hospital in Eastern France between 10/11/2021 and 7/3/2022, and who were deemed eligible for rehabilitation by the treating physician. Patients were interviewed before discharge. Interviews were transcribed and analysed by thematic analysis. We administered the Global Physical Activity Questionnaire (GPAQ) questionnaire to all participants. RESULTS: Of 17 eligible patients, 15 were interviewed, at which point saturation was reached. The majority were males (n = 13, 86%), median age 54 years (41-61). Three key themes emerged: Firstly, there is a mismatch between patients' perceptions of their physical activity and actual level of activity as assessed by objective tools. Second, cardiac rehabilitation is seen as a vector for information about the return to home after AMI. Third, regarding the intention to change lifestyle, there are persisting obstacles, drivers, fears and expectations. CONCLUSION: Patients with AMI often overestimate how physically active they are. Even close to discharge, patients have persisting informational needs, and many see cardiac rehabilitation as a means to obtain this information, rather than as a therapeutic intervention.

Tools for the Assessment of Risk-Taking Behavior in Older Adults with Mild Dementia: A Cross-Sectional Clinical Study.

Diseases such as Alzheimer's cause an alteration of cognitive functions, which can lead to increased daily risk-taking in older adults living at home. The assessment of decision-making abilities is primarily based on clinicians' global analysis. Usual neuropsychological tests such as the MoCA (Montreal Cognitive Assessment) cover most of the cognitive domains and include mental flexibility tasks. Specific behavioral tasks for risk-taking, such as the Balloon Analogue Risk Task (BART) or the Iowa Gambling Task (IGT), have been developed to assess risk-taking behavior, particularly in the field of addictology. Our cross-sectional study aims to determine whether the MoCA global cognitive assessment could be used as a substitute for behavioral tasks in the assessment of risky behavior. In the current study, 24 patients (age: 82.1 ± 5.9) diagnosed with mild dementia completed the cognitive assessment (MoCA and executive function assessment) and two behavioral risk-taking tasks (BART, simplified version of the IGT). Results revealed no relationship between scores obtained in the MoCA and behavioral decision-making tasks. However, the two tasks assessing risk-taking behavior resulted in concordant risk profiles. In addition, patients with a high risk-taking behavior profile on the BART had better Trail Making Test (TMT) scores and thus retained mental flexibility. These findings suggest that MoCA scores are not representative of risk-taking behavioral inclinations. Thus, additional clinical tests should be used to assess risk-taking behavior in geriatric settings. Executive function measures, such as the TMT, and behavioral laboratory measures, such as the BART, are recommended for this purpose.

Adaptations of the balloon analog risk task for neuroimaging settings: a systematic review.

Introduction: The Balloon Analog Risk Task (BART), a computerized behavioral paradigm, is one of the most common tools used to assess the risk-taking propensity of an individual. Since its initial behavioral version, the BART has been adapted to neuroimaging technique to explore brain networks of risk-taking behavior. However, while there are a variety of paradigms adapted to neuroimaging to date, no consensus has been reached on the best paradigm with the appropriate parameters to study the brain during risk-taking assessed by the BART. In this review of the literature, we aimed to identify the most appropriate BART parameters to adapt the initial paradigm to neuroimaging and increase the reliability of this tool. Methods: A systematic review focused on the BART versions adapted to neuroimaging was performed in accordance with PRISMA guidelines. Results: A total of 105 articles with 6,879 subjects identified from the PubMed database met the inclusion criteria. The BART was adapted in four neuroimaging techniques, mostly in functional magnetic resonance imaging or electroencephalography settings. Discussion: First, to adapt the BART to neuroimaging, a delay was included between each trial, the total number of inflations was reduced between 12 and 30 pumps, and the number of trials was increased between 80 and 100 balloons, enabling us to respect the recording constraints of neuroimaging. Second, explicit feedback about the balloon burst limited the decisions under ambiguity associated with the first trials. Third, employing an outcome index that provides more informative measures than the standard average pump score, along with a model incorporating an exponential monotonic increase in explosion probability and a maximum explosion probability between 50 and 75%, can yield a reliable estimation of risk profile. Additionally, enhancing participant motivation can be achieved by increasing the reward in line with the risk level and implementing payment based on their performance in the BART. Although there is no universal adaptation of the BART to neuroimaging, and depending on the objectives of a study, an adjustment of parameters optimizes its evaluation and clinical utility in assessing risk-taking.

Fake or fantasy: rapid dissociation between strategic content monitoring and reality filtering in human memory.

Memory verification is crucial for meaningful behavior. Orbitofrontal damage may impair verification and induce confabulation and inappropriate acts. The strategic retrieval account explains this state by deficient monitoring of memories' precise content, whereas the reality filter hypothesis explains it by a failure of an orbitofrontal mechanism suppressing the interference of memories that do not pertain to reality. The distinctiveness of these mechanisms has recently been questioned. Here, we juxtaposed these 2 mechanisms using high-resolution evoked potentials in healthy subjects who performed 2 runs of a continuous recognition task which contained pictures that precisely matched or only resembled previous pictures. We found behavioral and electrophysiological dissociation: Strategic content monitoring was maximally challenged by stimuli resembling previous ones, whereas reality filtering was maximally challenged by identical stimuli. Evoked potentials dissociated at 200-300 ms: Strategic monitoring induced a strong frontal negativity and a distinct cortical map configuration, which were particularly weakly expressed in reality filtering. Recognition of real repetitions was expressed at 300-400 ms, associated with ventromedial prefrontal activation. Thus, verification of a memory's concordance with the past (its content) dissociates from the verification of its concordance with the present. The role of these memory control mechanisms in the generation of confabulations and disorientation is discussed.

Audience Interbrain Synchrony During Live Music Is Shaped by Both the Number of People Sharing Pleasure and the Strength of This Pleasure.

The study of interbrain coupling in a group of people attending a concert together is a favorable framework to estimate group emotions and more precisely emotional connection between people sharing situations in the same environment. It offers the advantage of studying interactions at the group level. By recording the cerebral activity of people from an audience during a concert using electroencephalography, we previously demonstrated that the higher the emotions and the physically closer the people were, the more the interbrain synchrony (IBS) was enhanced. To further investigate the parameters that shaped inter-brain synchronization in this context, we now focus on the emotional dynamics of the group as a whole by identifying specific moments in the concert that evoked strong or weak emotions, as well as strong or weak emotional cohesion between individuals. We demonstrated that audience interbrain synchrony is mainly associated with experiencing high musical pleasure and that the group emotional cohesion can enhance IBS, but alone is not the major parameter that shapes it in this context.

Vocal melody and musical background are simultaneously processed by the brain for musical predictions.

Musical pleasure is related to the capacity to predict and anticipate the music. By recording early cerebral responses of 16 participants with electroencephalography during periods of silence inserted in known and unknown songs, we aimed to measure the contribution of different musical attributes to musical predictions. We investigated the mismatch between past encoded musical features and the current sensory inputs when listening to lyrics associated with vocal melody, only background instrumental material, or both attributes grouped together. When participants were listening to chords and lyrics for known songs, the brain responses related to musical violation produced event-related potential responses around 150-200 ms that were of a larger amplitude than for chords or lyrics only. Microstate analysis also revealed that for chords and lyrics, the global field power had an increased stability and a longer duration. The source localization identified that the right superior temporal and frontal gyri and the inferior and medial frontal gyri were activated for a longer time for chords and lyrics, likely caused by the increased complexity of the stimuli. We conclude that grouped together, a broader integration and retrieval of several musical attributes at the same time recruit larger neuronal networks that lead to more accurate predictions.

Interbrain emotional connection during music performances is driven by physical proximity and individual traits.

How musical emotions and the pleasure derived from music, regardless of the musical valence, can be shared between individuals is a fascinating question, and investigating it can shed light on the function of musical reward. We carried out our investigations in a natural setting during an international competition for orchestra conductors. Participants (n = 15) used a dedicated smartphone app to report their subjective emotional experiences in real time while we recorded their cerebral activity using electroencephalography and their electrodermal activity. The overall behavioral real-time behavioral ratings suggest a possible social influence on the reported and felt pleasure. The physically closer the participants, the more similar their reported pleasure. By calculating the interindividual cerebral coherence (n = 21 pairs), we showed that when people simultaneously reported either high or low pleasure, their cerebral activities were closer than for simultaneous neutral pleasure reports. Participants' skin conductance levels were also more coupled when reporting higher emotional degrees simultaneously. More importantly, the participants who were physically closer had higher cerebral coherence, but only when they simultaneously reported a high level of pleasure. We propose that emotional contagion and/or emotional resonance mechanisms could explain why a form of "emotional connecting force" arises between people during shared appraisal situations.

Rapid consolidation and the human hippocampus: intracranial recordings confirm surface EEG.

Diverse studies demonstrated that although immediately repeated stimuli are better and faster recognized than stimuli repeated after a delay, this comes at the price of less-efficient long-term retention. A recent-evoked potential study using source estimation of high-resolution scalp EEG indicated that while immediate repetition induced a strikingly different electrical activity than new items in the left-medial temporal lobe (MTL) after 200-300 ms, delayed repetition did not. In this study, we recorded evoked potentials in two epileptic patients with intracranial depth electrodes in diverse temporal and frontal areas as they performed the same task as in the previous study. We found that immediate repetition induced increase of neural activity specifically in the left MTL between 250 and 400 ms compared to new items and items repeated after a delay. The findings are important in two ways. First, they support our previous conclusion that novel information immediately initiates a consolidation process involving the left-hippocampal area, which remains vulnerable during active maintenance and increases its effectiveness during off-line processing. Second, they indicate that source estimation based on high-resolution scalp EEG correctly localizes the current source of electrical activity in midline structures like the MTL.

Exploring the informational sources of metaperception: the case of Change Blindness Blindness.

Perceivers generally show a poor ability to detect changes, a condition referred to as "Change Blindness" (CB). They are, in addition, "blind to their own blindness". A common explanation of this "Change Blindness Blindness" (CBB) is that it derives from an inadequate, "photographical" folk-theory about perception. This explanation, however, does not account for intra-individual variations of CBB across trials. Our study aims to explore an alternative theory, according to which participants base their self-evaluations on two activity-dependent cues, namely search time and perceived success in prior trials. These cues were found to influence self-evaluation in two orthogonal ways: success-feedback influenced self-evaluation in a global, contextual way, presumably by recalibrating the norm of adequacy for the task. Search time influenced it in a local way, predicting the success of a given trial from its duration.

Sport Practice Enhances Athletes' Observation Capacity: Comparing Scenic Change Detection in Open and Closed Sports.

Domain-specific knowledge guides our attention and thus influences our perception. Prior change-blindness research has shown that expert athletes can spot meaningful scene changes more quickly than novices, but less is known of whether this expertise is modulated differentially between open and closed sporting activities. We presented 81 individuals (20 gymnasts, 19 rock climbers, 22 parkour practitioners, and 20 control participants) with alternating sequences of images that corresponded to the habitual training landscapes of each group (gymnasiums, rock cliffs, and urban environments, respectively). We included contextual and non-contextual scenic changes to evaluate whether athletes were generally aware of their environments, or whether their observation strategies only targeted sport-related environmental elements. Among these three athletic endeavors, we found that gymnasts were faster at detecting changes in their environment, irrespective of whether or not these changes were contextual to the sports involved. Expert rock climbers presented a domain-specific expertise that was improved even further for contextual changes. Parkour practitioners presented the fastest reaction times in the urban environment and some of the best reaction times for all types of changes. These results confirm that an ability to read the environment is an integral aspect of practice in open-skilled sports, while skills of athletes in closed-skilled sports are more closely related to motor skill repetitions in constant environments. Thus, open skill training may benefit athletes' guidance of attention. Our finding that parkour practitioners appeared to have developed the widest perceptual abilities was probably linked to these athletes' extremely wide range of practice environments and with the constant demands of this sport to find solutions in random natural environments that that are not purposely designed for the sport.

Towards a Functional Neuromarker of Impulsivity: Feedback-Related Brain Potential during Risky Decision-Making Associated with Self-Reported Impulsivity in a Non-Clinical Sample.

Risk-taking is part of the multidimensional nature of impulsivity, consisting of an active engagement in behaviors or choices with potentially undesirable results, with probability as the cost for an expected reward. In order to understand the neurophysiological activity during risky behavior and its relationship with other dimensions of impulsivity, we have acquired event-related-potential (ERP) data and self-reported impulsivity scores from 17 non-clinical volunteers. They underwent high-resolution electroencephalography (HR-EEG) combined with an adapted version of the Balloon Analogue Risk Task (BART), and completed the Barratt Impulsiveness Scale (BIS-10) and the Urgency, Premeditation, Perseverance, Sensation Seeking, Impulsive Behavior Scale (UPPS). The ERP components were sensitive to valence (FRN, P300) and risk/reward magnitude (SPN, RewP). Our main finding evidenced a positive correlation between the amplitude of the P300 component following positive feedback and both the global UPPS score and the (lack of) perseverance UPPS subscale, significant for several adjacent electrodes. This finding might suggest an adaptive form of impulsive behavior, which could be associated to the reduction on the difference of the P300 amplitude following negative and positive feedback. However, further investigation with both larger clinical and non-clinical samples is required.

Added value of functional neuroimaging to assess decision-making capacity of older adults with neurocognitive disorders: protocol for a prospective, monocentric, single-arm study (IMAGISION).

INTRODUCTION: Assessment of decision-making capacity (DMC) is essential in daily life as well as for defining a person-centred care plan. Nevertheless, in ageing, especially if signs of dementia appear, it becomes difficult to assess decision-making ability and raises ethical questions. Currently, the assessment of DMC is based on the clinician's evaluation, completed by neuropsychological tests. Functional MRI (fMRI) could bring added value to the diagnosis of DMC in difficult situations. METHODS AND ANALYSIS: IMAGISION is a prospective, monocentric, single-arm study evaluating fMRI compared with clinical assessment of DMC. The study will begin during Fall 2021 and should be completed by Spring 2023. Participants will be recruited from a memory clinic where they will come for an assessment of their cognitive abilities due to decision-making needs to support ageing in place. They will be older people over 70 years of age, living at home, presenting with a diagnosis of mild dementia, and no exclusion criteria of MRI. They will be clinically assessed by a geriatrician on their DMC, based on the neuropsychological tests usually performed. Participants will then perform a behavioural task in fMRI (Balloon Analogue Risk Task) to analyse the activation areas. Additional semistructured interviews will be conducted to explore real life implications. The main analysis will study concordance/discordance between the clinical classification and the activation of fMRI regions of interest. Reclassification as 'capable', based on fMRI, of patients for whom clinical diagnosis is 'questionable' will be considered as a diagnostic gain. ETHICS AND DISSEMINATION: IMAGISION has been authorised by a research ethics board (Comité de Protection des Personnes, Bordeaux, II) in France, in accordance with French legislation on interventional biomedical research, under the reference IDRCB number 2019-A00863-54, since 30 September 2020. Participants will sign an informed consent form. The results of the study will be presented in international peer-reviewed scientific journals, international scientific conferences and public lectures. TRIAL REGISTRATION NUMBER: NCT03931148.

Chronic exposure to glucocorticoids induces suboptimal decision-making in mice.

Anxio-depressive symptoms as well as severe cognitive dysfunction including aberrant decision-making (DM) are documented in neuropsychiatric patients with hypercortisolaemia. Yet, the influence of the hypothalamo-pituitary-adrenal (HPA) axis on DM processes remains poorly understood. As a tractable mean to approach this human condition, adult male C57BL/6JRj mice were chronically treated with corticosterone (CORT) prior to behavioural, physiological and neurobiological evaluation. The behavioural data indicate that chronic CORT delays the acquisition of contingencies required to orient responding towards optimal DM performance in a mouse Gambling Task (mGT). Specifically, CORT-treated animals show a longer exploration and a delayed onset of the optimal DM performance. Remarkably, the proportion of individuals performing suboptimally in the mGT is increased in the CORT condition. This variability seems to be better accounted for by variations in sensitivity to negative rather than to positive outcome. Besides, CORT-treated animals perform worse than control animals in a spatial working memory (WM) paradigm and in a motor learning task. Finally, Western blotting neurobiological analyses show that chronic CORT downregulates glucocorticoid receptor expression in the medial Prefrontal Cortex (mPFC). Besides, corticotropin-releasing factor signalling in the mPFC of CORT individuals negatively correlates with their DM performance. Collectively, this study describes how chronic exposure to glucocorticoids induces suboptimal DM under uncertainty in a mGT, hampers WM and motor learning processes, thus affecting specific emotional, motor, cognitive and neurobiological endophenotypic dimensions relevant for precision medicine in biological psychiatry.