Brain-to-Brain Coupling in the Gamma-Band as a Marker of Shared Intentionality

Cooperation and competition are two ways of social interaction keys to life in society. Recent EEG-based hyperscanning studies reveal that cooperative and competitive interactions induce an increase in interbrain coupling. However, whether this interbrain coupling effect is just a reflection of inter-subject motor coordination or can also signal the type of social interaction is unknown. Here, we show that behavioral coordination and social interaction type can be distinguished according to the frequency of oscillation in which the brains are coupled. We use EEG to simultaneously measure the brain activity of pairs of subjects, while they were performing a visual cue-target task in a cooperative and competitive manner. Behavioral responses were quasi-simultaneous between subject pairs for both competitive and cooperative conditions, with faster average response times for the competitive condition. Concerning brain activity, we found increased interbrain coupling in theta band (3–7 Hz) during cooperation and competition, with stronger coupling during competitive interactions. This increase of interbrain theta coupling correlated with a decrease in reaction times of the dyads. Interestingly, we also found an increase in brain-to-brain coupling in gamma band (38–42 Hz) only during cooperative interactions. Unlike the theta coupling effect, the gamma interbrain coupling did not correlate with dyads’ reaction times. Taken together, these results suggest that theta interbrain coupling could be linked to motor coordination processes common to cooperative and competitive interactions, while gamma brain-to-brain coupling emerges as an electrophysiological marker of shared intentionality during cooperative interactions

Implementing EEG hyperscanning setups.

Hyperscanning refers to obtaining simultaneous neural recordings from more than one person (Montage et al., 2002 [1]), that can be used to study interactive situations. In particular, hyperscanning with Electroencephalography (EEG) is becoming increasingly popular since it allows researchers to explore the interactive brain with a high temporal resolution. Notably, there is a 40-year gap between the first instance that simultaneous measurement of EEG activity was mentioned in the literature (Duane and Behrendt, 1965 [2]), and the first actual description of an EEG hyperscanning setup being implemented (Babiloni et al., 2006 [3]). To date, specific EEG hyperscanning devices have not yet been developed and EEG hyperscanning setups are not usually described with sufficient detail to be easily reproduced. Here, we offer a step-by-step description of solutions to many of these technological challenges. Specifically, we describe and provide customized implementations of EEG hyperscanning setups using hardware and software from different companies: Brain Products, ANT, EGI, and BioSemi. •Necessary details to set up a functioning EEG hyperscanning protocol are provided.•The setups allow independent measures and measures of synchronization between the signals of two different brains.•Individual electrical Ground and Reference is obtained in all discussed systems

Brain-to-Brain Coupling in the Gamma-Band as a Marker of Shared Intentionality

Cooperation and competition are two ways of social interaction keys to life in society. Recent EEG-based hyperscanning studies reveal that cooperative and competitive interactions induce an increase in interbrain coupling. However, whether this interbrain coupling effect is just a reflection of inter-subject motor coordination or can also signal the type of social interaction is unknown. Here, we show that behavioral coordination and social interaction type can be distinguished according to the frequency of oscillation in which the brains are coupled. We use EEG to simultaneously measure the brain activity of pairs of subjects, while they were performing a visual cue-target task in a cooperative and competitive manner. Behavioral responses were quasi-simultaneous between subject pairs for both competitive and cooperative conditions, with faster average response times for the competitive condition. Concerning brain activity, we found increased interbrain coupling in theta band (3–7 Hz) during cooperation and competition, with stronger coupling during competitive interactions. This increase of interbrain theta coupling correlated with a decrease in reaction times of the dyads. Interestingly, we also found an increase in brain-to-brain coupling in gamma band (38–42 Hz) only during cooperative interactions. Unlike the theta coupling effect, the gamma interbrain coupling did not correlate with dyads’ reaction times. Taken together, these results suggest that theta interbrain coupling could be linked to motor coordination processes common to cooperative and competitive interactions, while gamma brain-to-brain coupling emerges as an electrophysiological marker of shared intentionality during cooperative interactions

Executive Functions and Theory of Mind in Teachers and Non-Teachers

Human teaching is a key behavior for the socialization of cultural knowledge. Previous studies suggest that human teaching behavior would support the development of executive and ToM skills, which in turn would refine the teaching behavior. Given this connection, it raises the question of whether subjects with professional training in teaching also have more efficient executive and ToM systems. To shed light on this issue, in the present study we compared the performance of professional teachers (N = 20, age range = 35–61 years) with a matched control group of non-teachers (N = 20, age range: 29–64 years) on tasks measuring working memory (Sternberg Task), cognitive flexibility (Wisconsin Card Sorting Test), executive control (Attention Network Test), along with online ToM skills (Frith–Happé Animations Task), emotion recognition (Reading the Mind in the Eyes Test) and first-order and second-order ToM (Yoni Task). We found that teachers were significantly more accurate on tasks involving cognitive flexibility (p = .014) and working memory (p = .040), and more efficient on tasks requiring executive control of attention (p = .046), compared to non-teachers. In ToM tasks, differences in accuracy between teachers and non-teachers were not found. But, teachers were slower to respond than non-teachers (about 2 s difference) on tasks involving emotion recognition (p = .0007) and the use of second-order affective ToM (p = .006). Collectively, our findings raise an interesting link between professional teaching and the development of cognitive skills critical for decision-making in challenging social contexts such as the classroom. Future research could explore ways to foster teachers' strengths in cognitive flexibility, working memory, and executive control of attention to enhance teaching strategies and student learning outcomes. Additionally, exploring factors behind slower response times in affective ToM tasks can guide teacher-training programs focused on interpersonal skills and improve teacher-student interactions

Efficiency of attentional networks in musicians and non-musicians

Music is a complex and properly human skill. Previous studies indicate that systematic musical training induces specific structural brain changes and improves audio-motor functions. However, whether these benefits can transfer into functional improvements of attentional skills is still little known. To shed light on this issue, in the present study we explored the relationship between long-term musical training and the efficiency of the attentional system. We used the attention network test (ANT) to compare the performance of the alerting, orienting and executive attentional networks of professional pianists against a matched group of non-musician adults. We found that musicians were significantly faster to respond across the ANT task, and that the executive attentional network was more efficient in musicians than non-musicians. We found no differences in the efficiency of the alerting and orienting networks between both groups. Interestingly, we found that the efficiency of the executive system improves with the years of musical training, even when controlling for age. We also found that the three attentional networks of the non-musicians were functionally independent. However, in the case of the musicians, the efficiency of the alerting and orienting systems was associated. These findings provide evidence of a potential transfer effect from systematic musical training into inhibitory attentional control

Oscillatory Brain Activity Reveals Linguistic Prints in the Quantity Code

Artículo de publicación ISINumber representations change through education, although it is currently unclear whether and how language could impact the magnitude representation that we share with other species. The most prominent view is that language does not play any role in modulating the core numeric representation involved in the contrast of quantities. Nevertheless, possible cultural hints on the numerical magnitude representation are currently on discussion focus. In fact, the acquisition of number words provides linguistic input that the quantity system may not ignore. Bilingualism offers a window to the study of this question, especially in bilinguals where the two number wording systems imply also two different numerical systems, such as in Basque-Spanish bilinguals. The present study evidences linguistic prints in the core number representational system through the analysis of EEG oscillatory activity during a simple number comparison task. Gamma band synchronization appears when Basque-Spanish bilinguals compare pairs of Arabic numbers linked through the Basque base-20 wording system, but it does not if the pairs are related through the base-10 system. Crucially, this gamma activity, originated in a left fronto-parietal network, only appears in bilinguals who learned math in Basque and not in equivalent proficiency bilinguals who learned math in Spanish. Thus, this neural index reflected in gamma band synchrony appears to be triggered by early learning experience with the base-20 numerical associations in Basque number words

El rol de las redes atencionales en el acceso a la magnitud numérica de fracciones en adultos

This study explored the relationship between the efficiency of alerting, orienting and executive control networks (attentional executive function) and accessing numerical magnitudes in adults, during a fraction comparison task, presenting pairs of fractions either with (CC) or without (WCC) common components. The results indicate that CC fractions are processed in a componential style, are affected by a whole number bias (WNB) and that performance in this block does not depend on the efficiency of attentional networks. By contrast, pairs of WCC fractions are processed in a holistic way, the WNB interacts with the numerical distance between fractions and performance in this block correlates with the efficiency of attentional orienting and executive control systems. Taken together, our findings show that the efficient selection of information and inhibitory control of intervening variables play an important role in processing fractions, particularly when the task requires the use of more holistic strategies to access the numerical magnitude of the fraction.En este estudio se indagó la relación entre la eficiencia de redes de alerta, orientación y control ejecutivo (función ejecutiva atencional) y el acceso a la magnitud numérica durante una tarea de comparación de fracciones con y sin componentes comunes (CC y SCC) en adultos. Los resultados indican que las fracciones CC son procesadas en un estilo componencial, son afectadas por el sesgo del número entero (SNE) y el rendimiento en este bloque no depende de la eficiencia de redes atencionales. Por el contrario, los pares de fracciones SCC son procesados de una forma holística, el SNE interactúa con la distancia numérica entre fracciones y el rendimiento en este bloque correlaciona con la eficiencia de los sistemas de orientación atencional y control ejecutivo. En su conjunto, nuestros hallazgos revelan que la eficiente selección de información y control inhibitorio de variables intervinientes juegan un rol importante en el procesamiento de fracciones, particularmente cuando la tarea demanda el uso de estrategias más holísticas para acceder a la magnitud numérica de la fracción.Associative Research Programme of CONICYT, FB 0003 / programme CONICYT PAI/Academia, 79130005 Initial Teacher Training of MECESUP3, UCH120

Brain to brain coupling in the gamma band as a marker of shared intentionality

Cooperation and competition are two ways of social interaction keys to life in society. Recent EEG-based hyperscanning studies reveal that cooperative and competitive interactions induce an increase in interbrain coupling. However, whether this interbrain coupling effect is just a reflection of inter-subject motor coordination or can also signal the type of social interaction is unknown. Here, we show that behavioral coordination and social interaction type can be distinguished according to the frequency of oscillation in which the brains are coupled. We use EEG to simultaneously measure the brain activity of pairs of subjects, while they were performing a visual cue-target task in a cooperative and competitive manner. Behavioral responses were quasi-simultaneous between subject pairs for both competitive and cooperative conditions, with faster average response times for the competitive condition. Concerning brain activity, we found increased interbrain coupling in theta band (3-7 Hz) during cooperation and competition, with stronger coupling during competitive interactions. This increase of interbrain theta coupling correlated with a decrease in reaction times of the dyads. Interestingly, we also found an increase in brain-to-brain coupling in gamma band (38-42 Hz) only during cooperative interactions. Unlike the theta coupling effect, the gamma interbrain coupling did not correlate with dyads' reaction times. Taken together, these results suggest that theta interbrain coupling could be linked to motor coordination processes common to cooperative and competitive interactions, while gamma brain-to-brain coupling emerges as an electrophysiological marker of shared intentionality during cooperative interactions.Comisión Nacional de Investigación Científica y Tecnológica (CONICYT) CONICYT FONDECYT 1170145 PIA-CONICYT Basal Funds for Centers of Excellence Project FB0003 FONDEQUIP Project EQM 150003 European Union (EU) 84088