Framing a Trust Game as a Power Game Greatly affects Interbrain Synchronicity between Trustor and Trustee

We used dual electroencephalography (EEG) to measure brain activity simultaneously in pairs of trustors and trustees playing a 15-round trust game framed as a \u201ctrust game\u201d versus a \u201cpower game\u201d. Four major findings resulted: first, earnings in each round were higher in the trust than in the power game. Second, in the trust game, reaction time for strategic deliberations was significantly longer for the trustee than the trustor. In the power game, however, the trustee took longer to think about how much money to repay, whereas the trustor took longer to think about how much money to invest. Third, prediction accuracy for the amount exchanged was higher in the trust game than in the power game. Fourth, interbrain synchronicity gauged with the phase-locking value of alpha bands in the brain \u2013 especially the frontal and central regions \u2013 was higher in the power game than in the trust game. We infer that this last finding reflects elevated mutual strategic deliberation in the power game. These behavioral and neuroscience-based findings give a better understanding of the framing effects of a trust game on the strategic deliberations of both trustor and trustee seeking to attain wealth. Copyright \ua9 2018 Informa UK Limite

Neurophysiological correlates underlying social behavioural adjustment of conformity

[eng] Conformity is the act of changing one’s behaviour to adjust to other human beings. It is a crucial social adaptation that happens when people cooperate, where one sacrifices their own perception, expectations, or beliefs to reach convergence with another person. The aim of the present study was to increase the understanding of the neurophysiological underpinnings regarding the social behavioural adjustment of conformity. We start by introducing cooperation and how it is ingrained in human behaviour. Then we explore the different processes that the brain requires for the social behavioural adjustment of conformity. To engage in this social adaptation, a person needs a self-referenced learning mechanism based on a predictive model that helps them track the prediction errors from unexpected events. Also, the brain uses its monitoring and control systems to encode different value functions used in action selection. The use of different learning models in neuroscience, such as reinforcement learning (RL) algorithms, has been a success story identifying learning systems by means of the mapped activity of different regions in the brain. Importantly, experimental paradigms which has been used to study conformity have not been based in a social interaction setting and, hence, the results, cannot be used to explain an inherently social phenomenon. The main goal of the present thesis is to study the neurophysiological mechanisms underlying the social behavioural adjustment of conformity and its modulation with repeated interaction. To reach this goal, we have first designed a new experimental task where conformity appears spontaneously between two persons and in a reiterative way. This design exposes learning acquisition processes, which require iterative loops, as well as other cognitive control mechanisms such as feedback processing, value-based decision making and attention. The first study shows that people who previously cooperate increase their level of convergence and report a significantly more satisfying overall experience. In addition, participants learning on their counterparts’ behaviour can be explained using a RL algorithm as opposed to when they do not have previously cooperated. In the second study, we have studied the event-related potentials (ERP) and oscillatory power underlying conformity. ERP results show different levels of cognitive engagement that are associated to distinct levels of conformity. Also, time-frequency analysis shows evidence in theta, alpha and beta related to different functions such as cognitive control, attention and, also, reward processing, supporting the idea that convergence between dyads acts as a social reward. Finally, in the third study, we explored the intra- and inter- oscillatory connectivity between electrodes related to behavioural convergence. In intra-brain oscillatory connectivity coherence, we have found two different dynamics related to attention and executive functions in alpha. Also, we have found that the learning about peer’s behaviour as computed using a RL is mediated by theta oscillatory connectivity. Consequently, combined evidence from Study 2 and Study 3 suggests that both cognitive control and learning computations happening in the social behavioural adaptation of conformity are signalled in theta frequency band. The present work is one of the first studies describing, with credible evidence, that conformity, when this occurs willingly and spontaneously rather than induced, engages different brain activity underlying reward-guided learning, cognitive control, and attention.[spa] La conformidad es el acto de cambiar el comportamiento de uno a favor de ajustarnos a otros seres humanos. Se trata de una adaptación crucial que ocurre cuando la gente coopera, donde uno sacrifica su propia percepción, expectativas o creencias en aras de conseguir una convergencia con la otra persona. El objetivo del presente estudio ha sido tratar de aportar a la comprensión de las estructuras neurofisiológicas que soportan un ajuste social como el de la conformidad. En la primera parte de esta tesis comenzamos hablando de la cooperación y lo profundamente arraigada que está en nuestro comportamiento. Más tarde exploramos diferentes procesos que el cerebro requiere en el ajuste social de la conformidad. Así pues, para involucrarse en esta adaptación social, una persona requiere de un mecanismo de aprendizaje auto-referenciado basado en un modelo predictivo que le ayude a seguir el rastro de los errores de predicción que acompañan a los eventos inesperados. Además, el cerebro usa sus sistemas de control y predicción para codificar diferentes funciones de valor usadas en la selección de acción. El uso de diferentes modelos de aprendizaje en neurociencia, como los algoritmos de aprendizaje por refuerzo (RL), han sido una historia de éxito a la hora de identificar los sistemas de aprendizaje a través del mapeo de la actividad de diferentes regiones del cerebro. Es importante destacar que los paradigmas experimentales que se han usado para estudiar la conformidad no se han basado en entornos de interacción social y que, por lo tanto, sus resultados no pueden usarse para explicar un fenómeno inherentemente social. El objetivo principal de la presente tesis es el estudio de los mecanismos neurofisiológicos que fundamentan el comportamiento de ajuste social de la conformidad y su modulación con la interacción repetida. Para alcanzar este objetivo, primero hemos diseñado una nueva tarea experimental en la que la conformidad aparece de forma espontánea entre dos personas y, además, de forma reiterativa. Este diseño permite exponer tanto los procesos de adquisición del aprendizaje, que requieren de ciclos iterativos, así como otros mecanismos de control cognitivo tales como el procesamiento de la retroalimentación, las tomas de decisiones basadas en procesos valorativos y la atención. El primer estudio nos muestra que la gente que coopera previamente incrementa sus niveles de convergencia y reportan significativamente una experiencia generalmente más satisfactoria en el experimento. Adicionalmente, un modelo de RL nos explica que los participantes tratan de aprender del comportamiento de sus parejas en mayor medida si estos han cooperado previamente. En el segundo estudio, hemos estudiado los potenciales relacionados con eventos (ERP) y el poder de las oscilaciones que sustentan la conformidad. Los estudios de ERP muestran diferentes niveles de implicación cognitiva asociados con diferentes niveles de conformidad. Además, los análisis de tiempo-frecuencia muestran evidencia en theta, alfa y beta relacionados con diferentes funciones como el control cognitivo, la atención, y, también, el procesamiento de la recompensa, apoyando la idea de que la convergencia entre díadas actúa como una recompensa social. Finalmente, en el tercer estudio, exploramos la conectividad oscilatoria intra e inter entre electrodos que se pudieran relacionar con la conducta de convergencia. A propósito de la conectividad oscilatoria coherente intra, hemos hallado dos dinámicas relacionadas con la atención y las funciones ejecutivas en alfa. Asimismo, hemos encontrado que el aprendizaje de la conducta de la pareja computada a través de RL está mediada a través de la conectividad oscilatoria de theta. Consecuentemente, la evidencia combinada entre el estudio 2 y el estudio 3 sugiere que conjuntamente el control cognitivo y las computaciones de aprendizaje que ocurren en la conducta de adaptación social de la conformidad están relacionadas con la actividad de la banda de frecuencia theta. Este trabajo constituye uno de los primeros estudios que describen, con evidencia creíble, que la conformidad, cuando ocurre voluntaria y espontáneamente a diferencia cuando esta es inducida, involucra actividad del cerebro que se fundamenta en el aprendizaje guiado por reforzamiento, el control cognitivo y la atención

Social perception of faces: Neuropsychological and behavioural investigations

This thesis concerns theoretical and empirical issues in face processing and facial trait perception. First, I present evidence that challenges two hypotheses proposed as alternatives to face specificity, namely the individuation and the expertise hypotheses. Inconsistent with the individuation hypothesis, an extensive investigation of a new case of acquired prosopagnosia (Herschel) revealed normal exemplar recognition memory for a wide variety of objects, and normal ability to discriminate between highly similar items within a novel object category. Inconsistent with the expertise hypothesis, Herschel and Florence, a second acquired prosopagnosic, showed normal learning profiles and response times putative of successful expertise acquisition in an eight-day training procedure with novel objects, demonstrating that faces are processed by specialised mechanisms not used for objects-of-expertise. Second, testing four patients with acquired prosopagnosia, I demonstrate that perceptual mechanisms underlying trait judgments are dissociable from those implicated in recognising identity. Furthermore, I show that perception of facial aggressiveness does not depend on mechanisms for facial sex recognition, and that normal facial trustworthiness judgments are likely to occur without intact recognition of facial expressions, therefore challenging the overgeneralisation theory in facial trait perception. Third, I present a series of experiments with healthy participants to characterise various properties of facial trait perception. Specifically, I examine: i) the role of facial width-to-height ratio in perceived trustworthiness; ii) the accuracy of facial trustworthiness judgments; iii) the interaction between facial trustworthiness and reputation; and iv) the interaction between face impressions and voice impressions. Overall, the findings of the present thesis have important implications for the nature of the mechanisms underlying facial identity processing, the organisation of facial trait perception and its relationship to other face perception abilities, as well as the physical, ecological, and multimodal aspects of facial trait perception

Neuroeconomics processes underlying decision-making in joint vs individual actions: a behavioral and EEG study on non-human primates

A hallmark of the successful evolution of our species could reside in the ability to optimize collective behavior in order to achieve goals otherwise unattainable by acting alone. Inter-individual motor coordination can be considered as a key feature of sharing actions with others. As much as advantageous though, acting together can also be costly since it requires special cognitive and motor skills. We know that non-human primates are able to coordinate their actions in a dyadic context by dynamically adapting their motor behavior in a way that favors inter-individual synchronization. However, this type of behavioral adaptation has been proved to entail a cost, which is evident in a reduction of successful monkeys’ performance when sharing actions for a common goal. In the recent years, the existence of internal models of the own and the other’s action has been hypothesized by several authors, but how these models are formed and coded at the neural level is still object of study. The currently most accredited hypothesis is that acting with others requires the ability to integrate one’s own and others’ action representations in a dyadic motor plan. In order to better understand the behavioral and neural underpinnings of sharing actions, we conducted three experiments. In the first part of this work (Experiment 1) we investigated whether, how and under which task conditions monkeys can improve their performance in a joint action task. To address these questions, we have investigated the influence of a pre-instructing “social cue” providing anticipatory information about action context (individual or joint). Our findings suggest that pre-instructing the action context increase the chances of dyadic success by establishing an optimal “kinematic setting” that ultimately facilitates inter-individual motor coordination. Moreover, we speculate that such joint performance improvement can be ascribe to a successful resort to a “we-representation”, possible only when the joint action is pre-cued. In the second part of this thesis (Experiment 2) we aimed at investigating monkeys’ ability to estimate the cost of acting together and to use this information to decide between acting alone or jointly with a partner. To this aim we trained two monkeys to choose between two possible goals, each associated to different action types (solo or together) and payoffs. Our findings suggest that their economic choice was not merely dictated by the reward offered but also by the action cost, whereby motor inter-individual coordination was evaluated as more demanding than individual action. In the third and final part (Experiment 3) we conducted dual neural recordings using electroencephalography (EEG) while the monkeys were working on the same task adopted in Experiment 2. Preliminary results demonstrate that monkeys’ response evoked by the two offers was modulated by the action type chosen or expected to be chosen by the partner. This provides, for the first time, evidence of the feasibility of studying neural correlates underlying value-based decision making in non-human primates by mean of EEG methods

Η Διερεύνηση της Παρορμητικότητας σε Ασθενείς με Οριακή Διαταραχή Προσωπικότητας: Το Δίλημμα του Φυλακισμένου ως Κοινωνική Πειραματική Συνθήκη για τη Μελέτη Λήψεως Αποφάσεων

Στην παρούσα διπλωματική εργασία επιχειρείται η έμμεση εξέταση της παρορμητικότητας, ως παράγοντα διερεύνησης εναλλακτικών και διλημματικών επιλογών του ατόμου ανάμεσα σε μια άμεση αλλά μικρή αμοιβή, έναντι μιας μεγάλης αλλά αναβεβλημένης αμοιβής (Delay-Discounting) του ερωτηματολογίου Kirby, η αξιολόγηση μιας σειράς διαστάσεων ψυχοπαθολογίας, παραγόντων προσωπικότητας, καθώς και του δείκτη ηθικής απόκρισης της προσωπικότητας, μεταξύ ασθενών με οριακή διαταραχή προσωπικότητας (ΟΔΠ) και υγιών μαρτύρων, κατά τη συμμετοχή τους στην υπολογιστική εκδοχή του Επαναλαμβανόμενου Παιχνιδιού του Διλήμματος του Φυλακισμένου (IPD), ως κοινωνικής πειραματικής συνθήκης για τη μελέτη λήψεως αποφάσεων. Συμπερασματικά, από τα στοιχεία της έρευνας φαίνεται να προκύπτει ότι οι δύο υπό μελέτη ομάδες οι οποίες υπεβλήθησαν σε αντίστοιχες μετρήσεις ψυχομετρικών δοκιμασιών διαφοροποιούνται συστηματικά ως προς το μεγαλύτερο αριθμό των παραγόντων ψυχοπαθολογίας, των διαστάσεων προσωπικότητας και ηθικής συμπεριφοράς. Σημαντικό εύρημα, ωστόσο, αποτελεί η απουσία διαφοροποίησης τους κατά την έμμεση εξέτασή τους στον ψυχολογικό άξονα της παρορμητικότητας, όπου δεν εντοπίστηκαν ουσιαστικές διαφορές.The present study attempts to examine impulsivity, indirectly, as a factor in exploring the individual's alternative and dilemmatic choices between an immediate but low reward versus a large but delayed reward (Delay-Discounting) of the Kirby questionnaire, the evaluation of a number of dimensions of psychopathology, personality factors, as well as the index of moral personality response, between patients with borderline personality disorder (BPD) and healthy controls, during their participation in the Repetitive Game of the Prisoner Dilemma - computer version (IPD), as a social treaty for the study of decision-making. In conclusion, the data of the research seem to show that the two study groups that underwent respective measurements of psychometric tests differ systematically in terms of the largest number of psychopathological factors, personality dimensions and moral behavior. An important finding, however, is their lack of differentiation when examined indirectly on the psychological axis of impulsivity, where no significant differences were found

Using MapReduce Streaming for Distributed Life Simulation on the Cloud

Distributed software simulations are indispensable in the study of large-scale life models but often require the use of technically complex lower-level distributed computing frameworks, such as MPI. We propose to overcome the complexity challenge by applying the emerging MapReduce (MR) model to distributed life simulations and by running such simulations on the cloud. Technically, we design optimized MR streaming algorithms for discrete and continuous versions of Conway’s life according to a general MR streaming pattern. We chose life because it is simple enough as a testbed for MR’s applicability to a-life simulations and general enough to make our results applicable to various lattice-based a-life models. We implement and empirically evaluate our algorithms’ performance on Amazon’s Elastic MR cloud. Our experiments demonstrate that a single MR optimization technique called strip partitioning can reduce the execution time of continuous life simulations by 64%. To the best of our knowledge, we are the first to propose and evaluate MR streaming algorithms for lattice-based simulations. Our algorithms can serve as prototypes in the development of novel MR simulation algorithms for large-scale lattice-based a-life models.https://digitalcommons.chapman.edu/scs_books/1014/thumbnail.jp

Mind the gap: gap factors in intercultural business communication : a study of German-Indian semi-virtual tech/engineering teams

While the affordances of technology have facilitated virtual modes of global collaboration, cultural variances and a geographically-dispersed environment can also lead to impaired group communication in team interaction. This qualitative study draws on data gathered from four organizations to investigate the miscommunication and cognitive dissonances reported by virtual German-Indian engineering/tech communities of practice. The study argues that it is not so much the performance or doing of a communicative act that creates dissonances, but the gaps, i.e., the absence or not-doing of certain communicative actions expected in a collaborative context. The gap factors are experienced as unfulfilled reciprocal expectations, and are classified and explored against three parameters: 1) the culture of a technological community of practice, 2) the power relations between the interactants, and 3) the consequences of virtual communication. The findings indicate a complementary divergence between the two groups regarding the nature of gaps. While the German teams report gaps in communicative efficiency and content caused e.g., by non-disclosure, euphemistic language and a deficiency in push communication, the Indian teams perceive gaps in relationality and affective signaling. At the same time, they are two sides of the same coin, with the divergences arising from the way in which the intersecting structural parameters are viewed as being salient in interaction. The study concludes with implications and suggestions for organizational practice

2016 GREAT Day Program

SUNY Geneseo’s Tenth Annual GREAT Day.https://knightscholar.geneseo.edu/program-2007/1010/thumbnail.jp