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Abstract

Cooperation behavior is a core question of study on social neuroscience. In the present study, inter-brain functional connectivity and cognitive performance were considered during joint which was failing. The cognitive performance and the EEG (brain oscillations from delta to beta) underlying the execution of joint-actions were recorded when dyads of participants executed synchronicity game and received reinforcing negative feedbacks A pre-feedback condition (cooperation) and a control condition (individual task, T0) were provided as well as a check for possible learning effect (time series analysis). Finally, correlation analysis was considered to assess the relation between behavioral and physiological levels. Results showed that the external feedback was able to modulate participants' responses in both behavioral and neural components with increased RTs and ERs after the negative reinforcement. Similarly, a reduced inter-brain connectivity was found, mainly localized within the superior frontal regions, and for low-frequency bands (delta and theta). In contrast pre-feedback condition showed the best performance in terms of both behavioral and brain-to-brain coupling activity. Moreover, the presence of significant correlations between RTs and inter-brain connectivity revealed that the failing cooperation induces significant negative effects on the cognitive and brain strategy in comparison with cooperative (pre-feedback) and individual (control) condition. The present study provides significant contribution to the identification of patterns of cognitive behavior and functional connectivity when social reinforcement is provided within dyads of participants by using a hyperscanning approach.

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... The motor synchronization application makes up 23% (14/60) of the research done with the MEG/EEG neuro-imaging methodology [41,58,[102][103][104][105][106][107][108][109][110][111][112][113]. The goal of these studies was to look at how participants are able to coordinate their actions with each other. ...
... The goal of these studies was to look at how participants are able to coordinate their actions with each other. This was most commonly done by asking participants to perform a motor task such as rhythmically tapping their fingers [41,104,105], following someone's lead (imitation) to tap the sensors at the same time [102,106,[108][109][110], or other motor/selective attention tasks [68,107,[111][112][113]. Motor synchronization studies were also done via a computer by asking participants to try to coordinate their response times to different matching/shapes games. ...
... Orientation. Less than half the studies, 43% (6/14), were done with participants facing each other, while 57% (8/14) of the studies employed the side-by-side orientation [102][103][104][105][106]110,112,113]. The studies that were done with participants facing each other used motor synchronization tasks like finger tapping. ...
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The aim of this study was to conduct a comprehensive review on hyperscanning research (measuring brain activity simultaneously from more than two people interacting) using an explicit systematic method, the preferred reporting items for systematic reviews and meta-analyses (PRISMA). Data were searched from IEEE Xplore, PubMed, Engineering Village, Web of Science and Scopus databases. Inclusion criteria were journal articles written in English from 2000 to 19 June 2019. A total of 126 empirical studies were screened out to address three specific questions regarding the neuroimaging method, the application domain, and the experiment paradigm. Results showed that the most used neuroimaging method with hyperscanning was magnetoencephalography/electroencephalography (MEG/EEG; 47%), and the least used neuroimaging method was hyper-transcranial Alternating Current Stimulation (tACS) (1%). Applications in cognition accounted for almost half the studies (48%), while educational applications accounted for less than 5% of the studies. Applications in decision-making tasks were the second most common (26%), shortly followed by applications in motor synchronization (23%). The findings from this systematic review that were based on documented, transparent and reproducible searches should help build cumulative knowledge and guide future research regarding inter-brain neural synchrony during social interactions, that is, hyperscanning research.
... Cooperation, in particular, can be defined as a social interaction between two or more agents that improve work efficiency [2]. In fact, cooperation is considered 5 as an interpersonal interaction that supports joined actions and that is able to affect the immediate and future behavior of the other individuals involved in the exchanges [3]. ...
... In recent years, hyperscanning technique applied to simultaneously record the neural activity from different multiple brains has been widely used to explore the neural mechanisms of so-20 cial interaction [7,8]. In fact, using this technology, the researchers found that multiple participants in the various social interactions tasks have a phenomenon of cross-brain neural synchronization, such as body movement coordination and imitation [9,10], audience-engagement during listening to political speeches [11], interactive decision-making [2,12], cooperation keypress [8,13] and face-to-face 25 communication [14,15]. These interesting results suggest that the phenomenon of cross-brain neural activity synchronization is widespread in daily life, which may play a key role in the social activities of humans and animals. ...
... Cross-brain functional connectivity can effectively evaluate the degree of cooperation and synchronization among multi-brain [2,41]. In this study, the PLV between the 48-channel time series of three pigeons in BP, pre-training STP, and post-training STP were calculated firstly, and then three 48*48 weighted adjacency matrices were obtained. ...
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Multi-brain network, also known as a social cooperative network, is formed by multiple animal or human brains, whose changes of functional connectivity in the intra- and inter-brain during construction are unclear at present. To investigate the intra- and inter-brain functional connectivity of pigeons while performing a social cooperation task, we designed a inter-brain synchronization task to train three pigeons to synchronize their neural activities using cross-brain neurofeedback. Then the neural signals of three pigeons were simultaneously recorded by using a hyperscanning approach, and inter-brain synchronization was calculated using the phase-locked value (PLV) online. Finally, the intra- and inter-brain functional connectivity of three pigeons were analyzed. We found that during long-term neurofeedback training, with the increasing of the inter-brain synchronization of three pigeons, the intra- and inter-brain functional connectivity also enhance significantly. Moreover, we also found that the above phenomenon relies on the external visual cue. These result suggest that the promotion of social cooperation is the result of the modulation between the intra- and inter-brain, which may be an underlying neural mechanism of communication and cooperation among individuals in social networks.
... Indeed, social and affective neuroscience strives to develop and apply methods that reveal a broader and more in-depth understanding of the way people interact with each other, including empathic and emotional mechanisms (Balconi & Canavesio, 2013;Venturella, Gatti, Vanutelli, & Balconi, 2017). A leading example of what has been called a "second person" social neuroscience (Schilbach, 2010) is the hyperscanning technique, a realistic and ecological paradigm which allows simultaneous recording of the cortical activity from two or more participants interacting together (Balconi, Gatti, & Vanutelli, 2018b;Montague, 2002). With these methods, people's behavior and associated brain activity patterns are no longer considered individually, but part of complex dynamics continuously adjusting and contaminating each other. ...
... It has been proposed that this mutual adaptation can generate an alignment at the behavioral level (Konvalinka, Vuusta, Roepstorffa, & Frith, 2010;Richardson, Marsh, Isenhower, Goodman, & Schmidt, 2007;Shockley, Santana, & Fowler, 2003), as well as the biological level of interpersonal tuning (IT) reflected by peripheral autonomic indices such as respiration, heart rate and skin conductance (Konvalinka et al., 2011;McFarland, 2001;Smith et al., 2011;Venturella et al., 2017), but also between brain responses (Astolfi et al., 2011;Balconi et al., 2018b;Balconi, Pezard, Nandrino, & Vanutelli, 2017;Dumas, Nadel, Soussignan, Martinerie, & Garnero, 2010). However, no specific research has directly tested whether there is an effect of increased IT induced by empathic behavior in the social context of employees-managers, particularly with a hyperscanning paradigm. ...
... However, it did not include tuning analyses. Starting from previous literature on hyperscanning in interactive situations (Balconi et al., 2018b;Balconi, Vanutelli, & Gatti, 2018;Liu et al., 2016;Liu, Saito, & Oi, 2015), we specifically focused on the prefrontal and frontal areas of the brain which are known to be involved in higher-order cognitive functions. Indeed, one of the fundamental requirements of organizational leaders is to regulate and monitor their and others' behavior (Zaccaro, Foti, & Kenny, 1991). ...
Article
Empirical management research has focused more on the investigation of important interpersonal factors that could be beneficial for a company’s well-being, including emotional and empathic engagement between managers and employees. Recent research has increasingly embodied a neuroscientific methods and paradigms. Specifically, the capacity to understand and mirror others’ feelings could result in a mutual adaptation that generates interpersonal tuning (IT). In the present study, IT was considered as interpersonal coordination of specific physiological processes between two or more subjects in interaction with each other. We measured IT by applying a hyperscanning approach with simultaneous recording of electroencephalographic (EEG) signals from two participants interacting together, in addition to interpersonal behavioral measures. 11 leaders and 11 employees were recruited and asked to role-play an employee performance review with a rating (R) or no rating (NR) condition. In the NR condition leaders describe by words the employee’s proficiency, while in R they provided a quantitative rating. The NR condition emerged as the more engaging situation in terms of empathic responses and mirroring. This difference was detectable from localization of neurophysiological effects over the frontopolar and frontal brain areas, and the higher synchronization of EEG delta frequency coherence. Behavioral resultsalso revealed an increase of self-perceived emotional tuning, agreement on content, and interpersonal cooperation in the NR condition compared to R condition. These effects were present in both leaders and employeesand have several implications for social and company well-being.
... Just a few hyperscanning studies using EEG and fNIRS have tested cooperative joint action. In particular, they focused on motor planning tasks (Konvalinka et al., 2014;Kourtis et al., 2013;Dumas et al., 2010Dumas et al., , 2012aDumas et al., , 2012b, guitarists playing (Vanzella et al., 2019;Müller et al., 2018Müller et al., , 2013Sänger et al., 2012), joint attention (Szymanski et al., 2017), conversation (Pérez et al., 2017;Kawasaki et al., 2013) and cognitive joint performance (Balconi et al., 2018a(Balconi et al., , 2018bCui et al., 2012). However, none of these studies focused on the co-representation, an ability that is at the basis of joint action. ...
... The literature reports a few ecological studies using EEG-hyperscanning for the investigation of joint actions (Balconi et al., 2018a;Konvalinka et al., 2014;Müller et al., 2018Müller et al., , 2013Pérez et al., 2017;Sänger et al., 2012), most of which focused on the synchronization ability or the interpersonal coordination during joint actions (for example, guitarists playing in ensemble or spontaneous imitation, Dumas et al., 2010Dumas et al., , 2012aDumas et al., , 2012b. Such studies exploited dual scanning to provide insights in the comprehension of the mechanisms at the basis of joint action, but they did not focus on co-representation, or they did not consider baseline conditions able to disentangle such aspect (probably because of the task complexity). ...
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Two-person neuroscience (2PN) is a recently introduced conceptual and methodological framework used to investigate the neural basis of human social interaction from simultaneous neuroimaging of two or more subjects (hyperscanning). In this study, we adopted a 2PN approach and a multiple-brain connectivity model to investigate the neural basis of a form of cooperation called joint action. We hypothesized different intra-brain and inter-brain connectivity patterns when comparing the interpersonal properties of joint action with non-interpersonal conditions, with a focus on co-representation, a core ability at the basis of cooperation. 32 subjects were enrolled in dual-EEG recordings during a computerized joint action task including three conditions: one in which the dyad jointly acted to pursue a common goal (joint), one in which each subject interacted with the PC (PC), and one in which each subject performed the task individually (Solo). A combination of multiple-brain connectivity estimation and specific indices derived from graph theory allowed to compare interpersonal with non-interpersonal conditions in four different frequency bands. Our results indicate that all the indices were modulated by the interaction, and returned a significantly stronger integration of multiple-subject networks in the joint vs. PC and Solo conditions. A subsequent classification analysis showed that features based on multiple-brain indices led to a better discrimination between social and non-social conditions with respect to single-subject indices. Taken together, our results suggest that multiple-brain connectivity can provide a deeper insight into the understanding of the neural basis of cooperation in humans.
... That is, when we perceive that our performance is inefficient, what will happen to our cognitive and neural responses? Balconi et al. (2018b) examined the effects of negative social feedback on cooperative learning. Brain activities were recorded simultaneously from two participants of the dyad during a task where participants received negative feedback after their joint action. ...
... Learning through social interaction is one of the most extraordinary capabilities of all social species, especially human beings (Marchiori and Warglien, 2008;Pan et al., 2018); examples include observation and imitation (Dumas et al., 2010;Iacoboni and Mazziotta, 2007), feedback and modification (Balconi et al., 2018a(Balconi et al., , 2018bBalconi and Vanutelli, 2018), as well as teaching and learning (Bevilacqua et al., 2018;Brockington et al., 2018;Holper et al., 2013). Yet, the brain basis of such social interactive learning remains poorly elucidated since conventional neuroimaging studies have only focused on isolated brains but not interacting minds (Liu and Pelowski, 2014). ...
Thesis
Social interactive learning is ubiquitous in human society. Learning through interactions with others plays an essential role in the daily lives of many people. Almost every day we communicate with peers or instructors, exchange information, observe and imitate other’s behaviors, with the purpose of learning. Yet how such interactive learning is parsed in the brains of interacting individuals remains poorly elucidated, and may be regarded as the “dark matter” of educational neuroscience. This thesis addresses the brain basis of interactive learning in three aspects: identification, modulation, and causation. Specifically, we investigated (i) whether interpersonal brain synchronization (IBS) could reliably identify interactive learning, (ii) how IBS and interactive learning could be modulated, and (iii) whether IBS plays a causal role in interactive learning. To approach these questions, we used functional near-infrared spectroscopy (fNIRS)-based hyperscanning to collect the neuroimaging data and naturalistic instructor-learner exchange as a principle experimental paradigm to realize interactive learning in the experiments. We developed a novel hyper-transcranial alternating current stimulation (tACS) system, which enabled manipulation of IBS between instructors and learners to examine the causative role of IBS in interactive learning. In the first study, we investigated the IBS between instructors and learners during more versus less interactive learning by computing the Wavelet Transform Coherence of instructor-learner brain activity. We have shown that IBS in the inferior frontal cortex reliably identifies and tracks interactive learning, and that IBS is more prominent when learning experience entails more turn-taking behaviors. Importantly, the unraveled IBS was associated with learning performance. In the second study, we further explore whether IBS and interactive learning could be modulated by the instructor’s verbal instruction. Results showed that compared to the explanation instruction, the scaffolding instruction elicited better learning performance and greater IBS. Besides, we adopted the machine learning to test IBS’s ability to discriminate between the two verbal instructions. We successfully showed that instructional strategies could be distinguished with a relatively high prediction performance. In the third study, we tested whether sleep deprivation (SD), which potentially impacts both social interactions and learning abilities, modulates interactive learning and IBS. Although learners performed below the baseline level immediately following SD, learning performance was comparable between sleep-rested (SR) and SD conditions after interactions with the instructor. Compared to SR, the SD condition induced greater IBS within instructor-learner dyads in the left inferior frontal cortex. Importantly, this IBS enhancement was associated with SD learners’ improved performance. Moreover, Granger Causality analysis showed that mean causalities from instructor to learner were significantly larger than vice versa following SD (but not SR). The fourth and final study investigated the causative role of IBS in interactive learning. By manipulating IBS through hyper-tACS, we demonstrated that externally induced IBS selectively biases interactive learning. Specifically, manipulation of IBS enhanced learners’ intonation performance and instructor-learner behavioral synchrony in a phase- (i.e., in-phase) and frequency-specific (i.e., 6 Hz) manner. The intonation performance also increased as a function of interpersonal synchrony. These results provide valuable insights into the functional role of IBS in interactive learning. The IBS may reflect the alignment of neural processes across learners and instructors. Such neural alignment impacts upon the acquisition of knowledge and information, and eventually upon the learning performance. Our studies hold strong relevance for real-world pedagogical practices and warrant future research to conduct clinical investigations that target learning deficits.
... Szymanski et al. (2017),Balconi et al. (2018) Partial directed coherenceSantamaria et al. (2019),Shehata et al. (2020) ...
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The study of brain-to-brain synchrony has a burgeoning application in the brain-computer interface (BCI) research, offering valuable insights into the neural underpinnings of interacting human brains using numerous neural recording technologies. The area allows exploring the commonality of brain dynamics by evaluating the neural synchronization among a group of people performing a specified task. The growing number of publications on brain-to-brain synchrony inspired the authors to conduct a systematic review using the PRISMA protocol so that future researchers can get a comprehensive understanding of the paradigms, methodologies, translational algorithms, and challenges in the area of brain-to-brain synchrony research. This review has gone through a systematic search with a specified search string and selected some articles based on pre-specified eligibility criteria. The findings from the review revealed that most of the articles have followed the social psychology paradigm, while 36% of the selected studies have an application in cognitive neuroscience. The most applied approach to determine neural connectivity is a coherence measure utilizing phase-locking value (PLV) in the EEG studies, followed by wavelet transform coherence (WTC) in all of the fNIRS studies. While most of the experiments have control experiments as a part of their setup, a small number implemented algorithmic control, and only one study had interventional or a stimulus-induced control experiment to limit spurious synchronization. Hence, to the best of the authors' knowledge, this systematic review solely contributes to critically evaluating the scopes and technological advances of brain-to-brain synchrony to allow this discipline to produce more effective research outcomes in the remote future.
... It is applied in all those cases where the strength of the relationship between two variables is a matter of interest, ranging from computational models [53] to neuroscience. Indeed, the same statistical model was applied in previous work to assess inter-brain synchrony with EEG [54] during failing cooperative interactions. In fact, similarly to the present paradigm, specific averaged values in response to the feedback were used instead of timeseries. ...
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Background Social behavior and interactions pervasively shape and influence our lives and relationships. Competition, in particular, has become a core topic in social neuroscience since it stresses the relevance and salience of social comparison processes between the inter-agents that are involved in a common task. The majority of studies, however, investigated such kind of social interaction via one-person individual paradigms, thus not taking into account relevant information concerning interdependent participants’ behavioral and neural responses. In the present study, dyads of volunteers participated in a hyperscanning paradigm and competed in a computerized attention task while their electrophysiological (EEG) activity and performance were monitored and recorded. Behavioral data and inter-brain coupling measures based on EEG frequency data were then computed and compared across different experimental conditions: a control condition (individual task, t0), a first competitive condition (pre-feedback condition, t1), and a second competitive condition following a positive reinforcing feedback (post-feedback condition, t2). Results Results showed that during competitive tasks participants’ performance was improved with respect to control condition (reduced response times and error rates), with a further specific improvement after receiving a reinforcing feedback. Concurrently, we observed a reduction of inter-brain functional connectivity (primarily involving bilateral prefrontal areas) for slower EEG frequency bands (delta and theta). Finally, correlation analyses highlighted a significant association between cognitive performance and inter-brain connectivity measures. Conclusions The present results may help identifying specific patterns of behavioral and inter-brain coupling measures associated to competition and processing of social reinforcements.
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In the present study, the social ranking perception in competition was explored. Brain response (alpha band oscillations, EEG; hemodynamic activity, O2Hb), as well as self-perception of social ranking, cognitive performance, and personality trait (Behavioral Activation System, BAS) were considered during a competitive joint-action. Subjects were required to develop a strategy to obtain a better outcome than a competitor (C) (in term of error rate, and response time, RT). A pre-feedback (without a specific feedback on the performance) and a post-feedback condition (which reinforced the improved performance) were provided. It was found that higher-BAS participants responded in greater measure to perceived higher cognitive performance (post-feedback condition), with increased left prefrontal activity, higher ranking perception, and a better real performance (reduced RTs). These results were explained in term of increased sense of self-efficacy and social position, probably based on higher-BAS sensitivity to reinforcing conditions. In addition, the hemispheric effect in favor of the left side characterized the competitive behavior, showing an imbalance for high-BAS in comparison to low-BAS in the case of a rewarding (post-feedback) context. Therefore, the present results confirmed the significance of BAS in modulating brain responsiveness, self-perceived social position, and real performance during an interpersonal competitive action which is considered highly relevant for social status.
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In the present research, we manipulated the perceived superior/inferior status during a competitive cognitive task. In two experiments, we created an explicit and strongly reinforced social hierarchy based on incidental rating on an attentional task. Based on our hypotheses, social rank may influence nonverbal cues (such as facial mimic related to emotional response), cortical lateralized activity in frontal areas (brain oscillations), and cognitive outcomes in response to rank modulation. Thus, the facial mimic (corrugators vs. zygomatic muscle activity), frequency bands (delta, theta, alpha, beta), and real cognitive performance [(error rate (ER); response times (RTs)] were considered. Specifically, a peer-group comparison was enrolled and an improved (experiment 1, N = 29) or decreased (experiment 2, N = 31) performance was artificially manipulated by the experimenter. Results showed a significant improved cognitive performance (decreased ER and RTs), an increased zygomatic activity (positive emotions), and a more prefrontal left-lateralized cortical response in the case of a perceived increased social ranking. On the contrary, a significant decreased cognitive performance (increased ER and RTs), an increased corrugators activity (negative emotions), and a less left-lateralized cortical response were observed as a consequence of a perceived decreased social ranking. Moreover, the correlational values revealed a consistent trend between behavioral (RTs) and EMG and EEG measures for both experiments. The present results suggest that social status not only guides social behavior, but it also influences cognitive processes and subjects' performance.
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The perception and interpretation of social hierarchies is a key part of our social life. In the present research we considered the activation of cortical areas, mainly the prefrontal cortex, related to social ranking perception in conjunction with some personality components (BAS - Behavioral Activation System - and BIS - Behavioral Inhibition System). In two experiments we manipulated the perceived superior/inferior status during a competitive cognitive task. Indeed, we created an explicit and strongly reinforced social hierarchy based on incidental rating in an attentional task. Specifically, a peer group comparison was undertaken and improved (Experiment 1) or decreased (Experiment 2) performance was artificially manipulated by the experimenter. For each experiment two groups were compared, based on a BAS and BIS dichotomy. Alpha band modulation in prefrontal cortex, behavioral measures (performance: error rate, ER; response times, RTs), and self-perceived ranking were considered. Repeated measures ANOVAs and regression analyses showed in Experiment 1 a significant improved cognitive performance (decreased ER and RTs) and higher self-perceived ranking in high-BAS participants. Moreover, their prefrontal activity was increased within the left side (alpha band decreasing). Conversely, in Experiment 2 a significant decreased cognitive performance (increased ER and RTs) and lower self-perceived ranking was observed in higher-BIS participants. Their prefrontal right activity was increased in comparison with higher BAS. The regression analyses confirmed the significant predictive role of alpha band modulation with respect of subjects' performance and self-perception of social ranking, differently for BAS/BIS components. The present results suggest that social status perception is directly modulated by cortical activity and personality correlates.
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Interpretation and analysis of electroencephalography (EEG) measurements relies on the correspondence of electrode scalp coordinates to structural and functional regions of the brain. An algorithm is introduced for automatic calculation of the International 10-20, 10-10, and 10-5 scalp coordinates of EEG electrodes on a boundary element mesh of a human head. The EEG electrode positions are then used to generate parcellation regions of the cerebral cortex based on proximity to the EEG electrodes. The scalp electrode calculation method presented in this study effectively and efficiently identifies EEG locations without prior digitization of coordinates. The average of electrode proximity parcellations of the cortex were tabulated with respect to structural and functional regions of the brain in a population of 20 adult subjects. Parcellations based on electrode proximity and EEG sensitivity were compared. The parcellation regions based on sensitivity and proximity were found to have 44.0±11.3% agreement when demarcated by the International 10-20, 32.4±12.6% by the 10-10, and 24.7±16.3% by the 10-5 electrode positioning system. The EEG positioning algorithm is a fast and easy method of locating EEG scalp coordinates without the need for digitized electrode positions. The parcellation method presented summarizes the EEG scalp locations with respect to brain regions without computation of a full EEG forward model solution. The reference table of electrode proximity versus cortical regions may be used by experimenters to select electrodes that correspond to anatomical and functional regions of interest.
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The present research intended first to confirm psychophysiological and cortical responses to valence- and arousal-manipulated stimuli and second to show how the BIS and BAS (Behavioural Inhibition and Activation System) personality characteristics correlated with these psychophysiological and cortical responses. Multiple measures were recorded, such as psychophysiological (skin conductance response, heart rate, and electromyography) and ERPs (event-related potentials) responses, during viewing IAPS figures, that varied in terms of pleasantness (appetitive vs. aversive) and arousing power (high vs. low intensity). Autonomic variables and two ERP positive deflections (P3 and LPP ERP effects) were found to be modulated by valence and arousal rating, with an increased response for high arousing and negative or positive stimuli in comparison with low arousing and neutral stimuli. Moreover, high BAS subjects were more responsive to positive than negative emotions, whereas high BIS subjects responded in greater measure to negative and arousing emotions. Findings were discussed in light of biphasic model of emotion comprehension.
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When two or more people coordinate their actions in space and time to produce a joint outcome, they perform a joint action. The perceptual, cognitive, and motor processes that enable individuals to coordinate their actions with others have been receiving increasing attention during the last decade, complementing earlier work on shared intentionality and discourse. This chapter reviews current theoretical concepts and empirical findings in order to provide a structured overview of the state of the art in joint action research. We distinguish between planned and emergent coordination. In planned coordination, agents' behavior is driven by representations that specify the desired outcomes of joint action and the agent's own part in achieving these outcomes. In emergent coordination, coordinated behavior occurs due to perception–action couplings that make multiple individuals act in similar ways, independently of joint plans. We review evidence for the two types of coordination and discuss potential synergies between them.
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Commitment is an important determinant of relationship stability. Previous studies demonstrated that relationship stability is influenced by several personality variables, one of which is conscientiousness. To account for the influence of conscientiousness on relationship stability, we propose a neurological model of commitment. The model assumes that conscientiousness and commitment are influenced by individual differences in anterior and mid-dorsolateral prefrontal (amDLPFC) functioning, and that conscientiousness is a partial mediator of the association between amDLPFC functioning and commitment. Results from two studies with dating couples are consistent with this model. Study 2 suggests that, relative to other conscientiousness facets, self-efficacy is a more likely mediator of the effect of amDLPFC functioning on commitment.
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The goal of this research was to investigate sub-band modulations in the mu domain in dyads performing different social coordination tasks. Dyads of subjects performed rhythmic finger movement under three different task conditions: intrinsic - maintain self-produced movement while ignoring their partner's movement; in-phase - synchronize with partner; and anti-phase - maintain syncopation with partner. Movement profiles of the dyads were used to estimate a synchronization index (SI) to verify differences in coordination according to each task. EEG was recorded during task performance and at baseline (partner's actions hidden from view). Log power ratios of mu band activity (active against baseline) were used to assess the relative levels of synchronization/de-synchronization in both the upper and lower mu bands. Results confirm a functional dissociation of lower (8-10 Hz) and upper (10-12 Hz) mu bands in social coordination tasks. Lower mu band activity was independent of specific modulations across tasks and hemispheric preferences. Upper mu band activity was sensitive to coordination tasks and exhibited marked differences between the hemispheres. Accentuated de-synchronization of right relative to left hemisphere in the anti-phase task appeared related to the greater demand of perceptual-motor discrimination. Left hemisphere de-synchronization in both in-phase and anti-phase coordination was interpreted in terms of successful production of imitation. Right hemisphere synchronization in the intrinsic task was interpreted as inhibition of an imitative response tendency. Functional dissociation of lower and upper mu band and hemispheric preferences exists in real-time social coordination. This research attests to the merit of analyzing sub-band activity in the alpha-mu domain in order to identify neural correlates of social coordination. Such 'neuromarkers' may be relevant for brain disorders such as apraxia and autism.
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We used Near-Infrared Spectroscopy (NIRS) to simultaneously measure brain activity in two people while they played a computer-based cooperation game side by side. Inter-brain activity coherence was calculated between the two participants. We found that the coherence between signals generated by participants' right superior frontal cortices increased during cooperation, but not during competition. Increased coherence was also associated with better cooperation performance. To our knowledge, this work represents the first use of a single NIRS instrument for simultaneous measurements of brain activity in two people. This study demonstrates the use of NIRS-based hyperscanning in studies of social interaction in a naturalistic environment.
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Emotion information processing may occur in two modes which are differently represented in conscious awareness. Fast online processing involves coarse-grained analysis of salient features, and is not represented in conscious awareness; offline processing takes hundreds of milliseconds to generate fine-grained analysis, and is represented in conscious awareness. These processing modes may be studied using event-related electroencephalogram theta and delta synchronization as a marker of emotion processing. Two experiments were conducted, which differed on the mode of emotional information presentation. In the explicit mode subjects were explicitly instructed to evaluate the emotional content of presented stimuli; in the implicit mode they performed a gender discrimination task. Firstly, we show that in both experiments theta and delta synchronization is stronger upon presentation of "emotional" than "neutral" stimuli, and in subjects who are more sensitive, or experience higher emotional involvement than in less sensitive or detached subjects. Secondly, we show that in the implicit mode theta and delta synchronization is more pronounced in an early (before 250 ms post-stimulus) processing stage, whereas in the explicit mode it is more pronounced in a later processing stage. Source localization analysis showed that implicit processing of angry and happy (relative to neutral) faces is associated with higher early (before 250 ms) theta synchronization in the right parietal cortex and the right insula, respectively. Explicit processing of angry and happy faces is associated with higher late (after 250 ms) theta synchronization in the left temporal lobe and bilateral prefrontal cortex, respectively.
Article
"Theory of Mind" (ToM), i.e., the ability to infer other persons' mental states, is a key function of social cognition. It is increasingly recognized to form a multidimensional construct. One differentiation that has been proposed is that between cognitive and affective ToM, whose neural correlates remain to be identified. We aimed to ascertain the possible role of the right dorsolateral prefrontal cortex (DLPFC) for cognitive ToM as opposed to affective ToM processes. 1Hz repetitive transcranial magnetic stimulation (rTMS) was used to interfere offline with cortical function of the right DLPFC in healthy male subjects who subsequently had to perform a computerized task assessing cognitive and affective ToM. RTMS over the right DLPFC induced a selective effect on cognitive but not affective ToM. More specifically, a significant acceleration of reaction times in cognitive ToM compared to affective ToM and control items was observed in the experimental (right DLPFC) compared to the control (vertex) rTMS stimulation condition. Our findings provide evidence for the functional independence of cognitive from affective ToM. Furthermore, they point to an important role of the right DLPFC within neural networks mediating cognitive ToM. Possible underlying mechanisms of the acceleration of cognitive ToM processing under rTMS are discussed.
Article
The present study explored the effect of the individual differences related to BIS and BAS (Behavioural Inhibition and Activation System) on brain oscillations, in response to appetitive and aversive emotional stimuli. EEG cortical measures (delta, theta, alpha, and gamma) were recorded, during viewing IAPS figures, that varied in terms of pleasantness and arousal. Withdrawal (BIS system) and appetitive (BAS system) behaviour showed opposite patterns of subjective responses. Also, a specific frontal network was found to be responsive to the relevance of emotional cues. Moreover an increased response for high arousing (negative and positive) stimuli in comparison with low arousing and neutral stimuli was found within the left and right frontal areas. Specifically delta and theta band have a significant role in monitoring the attentional significance of emotions. Finally, the effects of subjective evaluation and individual differences were discussed at light of the two-dimensional model of emotion processing, that is the valence and the arousing power of emotional cues.
Article
The study aimed to explore the modulation of frequency bands (delta, theta, alpha-1 and alpha-2, and gamma) in response to emotional face within different post-stimulus time intervals (50-450 ms). Twenty adults looked at emotional (happy, sad, angry, fearful) or neutral faces. EEG results showed that motivational significance of face can modulate frequency bands, specifically for theta and gamma. Moreover, gamma can be varied related to degree of arousing feature (high or low) of facial expression. As a function of time, ANOVA and regression analysis revealed that emotional discrimination by gamma and theta is observable mainly within 150-250 time interval and, as revealed also by coherence analysis, that it is more distributed on the anterior-right (theta) or right (gamma) side of the scalp for the emotional stimuli, whereas delta is maximally increased within 250-350 interval and it is more posteriorly (parietal site) distributed for all the stimulus type. We proposed that band modulations respond to variations in processing emotional face, and, whereas delta reflects updating of the stimulus, and theta responds to the emotional significance of face, gamma reflects differences in the arousing power of facial expression.
Article
Our recent event-related potential (ERP) studies showed that phase-locked electrophysiological activities mediate both early emotional sharing and late cognitive evaluation during empathy for pain. However, whether non-phase-locked neural oscillations are involved in empathic responses remains unknown. To investigate the functional role of non-phase-locked theta (3-8 Hz) and alpha (9-14 Hz) oscillations in empathy for pain, we recorded electroencephalogram (EEG) from healthy adults who performed pain judgment of pictures of hands in painful or neutral situations. Wavelet analysis was used to calculate EEG spectral power with high time-frequency (TF) resolution. We found that, relative to neutral stimuli, painful stimuli induced increased theta event-related synchronization (ERS) at 200-500 ms but decreased alpha event-related desynchronization (ERD) at 200-400 ms, providing evidence for the engagement of theta and alpha activity in empathy for pain. In addition, subjective ratings of perceived pain and self-unpleasantness positively correlated with theta band ERS but negatively correlated with alpha band ERD related to painful stimuli, suggesting that theta and alpha oscillations are respectively involved in emotional sharing and regulation during empathy for pain. Finally, the long-latency upper theta (6-8 Hz) and alpha band TF power significantly decreased by repeated exposure to painful stimuli, indicating short-term adaptive changes of empathy-related neural activity.
Oscillations in the alpha and beta bands can display either an event-related blocking response or an event-related amplitude enhancement. The former is named event-related desynchronization (ERD) and the latter event-related synchronization (ERS). Examples of ERS are localized alpha enhancements in the awake state as well as sigma spindles in sleep and alpha or beta bursts in the comatose state. It was found that alpha band activity can be enhanced over the visual region during a motor task, or during a visual task over the sensorimotor region. This means ERD and ERS can be observed at nearly the same time; both form a spatiotemporal pattern, in which the localization of ERD characterizes cortical areas involved in task-relevant processing, and ERS marks cortical areas at rest or in an idling state.
Article
A system for electrode placement is described. It is designed for studies on topography and source analysis of spontaneous and evoked EEG activity. The proposed system is based on the extended International 10-20 system which contains 74 electrodes, and extends this system up to 345 electrode locations. The positioning and nomenclature of the electrode system is described, and a subset of locations is proposed as especially useful for modern EEG/ERP systems, often having 128 channels available. Similar to the extension of the 10-20 system to the 10-10 system ("10% system"), proposed in 1985, the goal of this new extension to a 10-5 system is to further promote standardization in high-resolution EEG studies.
Article
Cooperation and competition are two basic modes of social cognition that necessitate monitoring of both one's own and others' actions, as well as adopting a specific mental set. In this fMRI, study individuals played a specially designed computer game, according to a set of predefined rules, either in cooperation with or in competition against another person. The hemodynamic response during these conditions was contrasted to that of the same subjects playing the game independently. Both cooperation and competition stances resulted in activation of a common frontoparietal network subserving executive functions, as well as the anterior insula, involved in autonomic arousal. Moreover, distinct regions were found to be selectively associated with cooperation and competition, notably the orbitofrontal cortex in the former and the inferior parietal and medial prefrontal cortices in the latter. This pattern reflects the different mental frameworks implicated in being cooperative versus competitive with another person. In accordance with evidence from evolutionary psychology as well as from developmental psychology, we argue that cooperation is a socially rewarding process and is associated with specific left medial orbitofrontal cortex involvement.
Article
In order to study the concurrent activity in subjects interacting in cooperation or competition activities, the issue of the simultaneous recording of their brain activity became mandatory. The simultaneous recording of neuroelectric activity of the brain is called "EEG hyperscanning". We would like present results obtained by EEG hyperscannings performed on a group of subjects engaged in a card game. The EEG hyperscannings have been performed with the simultaneous use of high resolution EEG devices on groups of four subjects while they were playing a card game. We estimated the concurrent activity in multiple brains of the group and we depicted the causal connections between regions of different brains. Results obtained in a study of several groups recorded by the EEG hyperscanning reveal larger activity in prefrontal and anterior cingulated cortex in different frequency bands for the player that start the game when compared to other players. EEG hyperscannings will open a different area for the study of neuroscience, in which the activity of multiple brains during social cooperation could be investigated.
Neural mechanisms of free-riding and cooperation in a public goods game: an EEG hyperscanning study
  • D Chung
  • K Yun
  • J Jeong
Chung, D., Yun, K., & Jeong, J. (2008). Neural mechanisms of free-riding and cooperation in a public goods game: an EEG hyperscanning study. International Conference of Cognitive Science.
Role of the basolateral amygdala in memory consolidation
  • D Paré
Paré, D. (2003). Role of the basolateral amygdala in memory consolidation. Progress in Neurobiology, 70(5), 409-420.