Autistic traits affect interpersonal motor coordination by modulating strategic use of role-based behavior

Background: Despite the fact that deficits in social communication and interaction are at the core of Autism Spectrum Conditions (ASC), no study has yet tested individuals on a continuum from neurotypical development to autism in an on-line, cooperative, joint action task. In our study, we aimed to assess whether the degree of autistic traits affects participants' ability to modulate their motor behavior while interacting in a Joint Grasping task and according to their given role. Methods: Sixteen pairs of adult participants played a cooperative social interactive game in which they had to synchronize their reach-to-grasp movements. Pairs were comprised of one ASC and one neurotypical with no cognitive disability. In alternate experimental blocks, one participant knew what action to perform (instructed role) while the other had to infer it from his/her partner’s action (adaptive role). When in the adaptive condition, participants were told to respond with an action that was either opposite or similar to their partner. Participants also played a non-social control game in which they had to synchronize with a non-biological stimulus. Results: In the social interactive task, higher degree of autistic trait s predicted less ability to mod ulate joint action according to one’s interactive role. In the non-social task, autistic traits did not predict differences in movement preparation and planning, thus ruling out the possibility that social interact ive task results were due to basic motor or executive function difficulties. Furthermore, when participants played the non-social game, the higher their autistic traits, the more they were interfered by the non-biological stimulus. Conclusions: Our study shows for the first time that high autistic traits predict a stereotypical interaction style when individuals are required to modulate their movements in order to coordinate with their partner according to their role in a joint action task. Specifically, the infrequent emergence of role-based motor behavior modulation during on-line motor cooperation in participants with high autistic traits sheds light on the numerous difficulties ASC have in nonverbal social interaction

Interactional leader-follower sensorimotor communication strategies during repetitive joint actions

Non-verbal communication is the basis of animal interactions. In dyadic leader – follower interactions, leaders master the ability to carve their motor behaviour in order to ‘signal’ their future actions and internal plans while these signals influence the behaviour of follower partners, who automatically tend to imitate the leader even in complementary interactions. Despite their usefulness, signalling and imitation have a biomechanical cost, and it is unclear how this cost – benefits trade-off is managed during repetitive dyadic interactions that present learnable regularities. We studied signalling and imitation dynamics (indexed by movement kinematics) in pairs of leaders and followers during a repetitive, rule-based, joint action. Trial-by-trial Bayesian model comparison was used to evaluate the relation between signalling, imitation and pair performance. The different models incorporate different hypotheses concerning the factors (past interactions versus online movements) influencing the leader’s signalling (or follower’s imitation) kinematics. This approach showed that (i) leaders’ signalling strategy improves future couple performance, (ii) leaders used the history of past interactions to shape their signalling, (iii) followers’ imitative behaviour is more strongly affected by the online movement of the leader. This study elucidates the ways online sensorimotor communication help individuals align their task representations and ultimately improves joint action performanc

Human adults prefer to cooperate even when it is costly

Funding: This research was supported by the European Research Council (ERC) under the European Union’s Seventh Framework Program [FP7/2007-2013/ERC Grant 609819], project SOMICS.Joint actions are cooperative activities where humans coordinate their actions to achieve individual and shared goals. While the motivation to engage in joint action is clear when a goal cannot be achieved by individuals alone, we asked whether humans are motivated to act together even when acting together is not necessary and implies incurring additional costs compared to individual goal achievement. Using a utility-based empirical approach, we investigated the extent of humans' preference for joint action over individual action, when the instrumental costs of performing joint actions outweigh the benefits. The results of five experiments showed that human adults have a stable preference for joint action, even if individual action is more effective to achieve a certain goal. We propose that such preferences can be understood as ascribing additional reward value to performing actions together.Publisher PDFPeer reviewe

Understanding joint action: Current theoretical and empirical approaches

Joint actions are omnipresent, ranging from a handshake between two people to the coordination of groups of people playing in an orchestra. We are highly skilled at coordinating our actions with those of others to reach common goals and rely on this ability throughout our daily lives. What are the social, cognitive and neural processes underlying this ability? How do others around us influence our task representations? How does joint action influence interpersonal interactions? How do language and gesture support joint action? What differentiates joint action from individual action? This article forms an introductory editorial to the field of joint action. It accompanies contributions to the special issue entitled "Current Issues in Joint Action Research". The issue brings together conceptual and empirical approaches on different topics, ranging from lower-level issues such as the link between perception and joint action, to higher-level issues such as language as a form of joint action

Multivariate characterisation of Italian monovarietal red wines using MIR spectroscopy

Aim: The aim of this study was to investigate the application of mid-infrared (MIR) spectroscopy combined with multivariate analysis, to provide a rapid screening tool for discriminating among different Italian monovarietal red wines based on the relationship between grape variety and wine composition in particular phenolic compounds. Methods and results: The MIR spectra (from 4000 to 700 cm\u20121) of 110 monovarietal Italian red wines, vintage 2016, were collected and evaluated by selected multivariate data analyses, including principal component analysis (PCA), linear discriminant analysis (DA), support vector machine (SVM), and soft intelligent modelling of class analogy (SIMCA). Samples were collected directly from companies across different regions of Italy and included 11 grape varieties: Sangiovese, Nebbiolo, Aglianico, Nerello Mascalese, Primitivo, Raboso, Cannonau, Teroldego, Sagrantino, Montepulciano and Corvina. PCA showed five wavelengths that mainly contributed to the PC1, including a much-closed peak at 1043 cm\u20121, which correspond to the C\u2013O stretch absorption bands that are important regions for glycerol, whereas the ethanol peaks at around 1085 cm\u20121. The band at 877 cm\u20121 are related to the C\u2013C stretching vibration of organic molecules, whereas the asymmetric stretching for C\u2013O in the aromatic \u2013OH group of polyphenols is within spectral regions from 1050 to 1165 cm\u20121. In particular, the (1175)\u20131100\u20131060 cm\u20121 vibrational bands are combination bands, involving C\u2013O stretching and O\u2013H deformation of phenolic rings. The 1166\u20131168 cm\u20121 peak is attributable to inplane bending deformations of C\u2013H and C\u2013O groups of polyphenols, respectively, for which polymerisation may cause a slight peak shift due to the formation of H-bridges. The best result was obtained with the SVM, which achieved an overall correct classification for up to 72.2% of the training set, and 44.4% for the validation set of wines, respectively. The Sangiovese wines (n=19) were split into two sub-groups (Sang-Romagna, n=12 and Sang-Tuscany, n=7) considering the indeterminacy of its origins, which is disputed between Romagna and Tuscany. Although the classification of three grape varieties was problematic (Nerello Mascalese, Raboso and Primitivo), the remaining wines were almost correctly assigned to their actual classes. Conclusions: MIR spectroscopy coupled with chemometrics represents an interesting approach for the classification of monovarietal Italian red wines, which is important in quality control and authenticity monitoring. Significance and impact of the study: Authenticity is a main issue in winemaking in terms of quality evaluation and adulteration, in particular for origin certified/protected wines, for which the added marketing value is related to the link of grape variety with the area of origin. This study is part of the D-wine project \u201cThe diversity of tannins in Italian red wines\u201d

A methodology for distinguishing copying and reconstruction in cultural transmission episodes

Information transmission between individuals through social learning is a foundational component of cultural evolution. However, how this transmission occurs is still debated. The copying account draws parallels with biological mechanisms for genetic inheritance, arguing that learners copy what they observe as they see it. On the other hand, the reconstruction account argues that learners recreate only what is relevant and reconstruct it using pragmatic inference, environmental and contextual cues. Distinguishing these two accounts empirically using typical transmission chain studies is difficult because they generate overlapping predictions. In this study we present an innovative methodological approach that generates different predictions of these accounts by manipulating the task context between model and learner in a transmission episode. We provide an empirical proof-of-concept showing that, when a model introduces embedded signals to their actions that are not intended to be transmitted, learners’ reproductions are more consistent with a process of reconstruction than copying

Phenolic extraction and mechanical properties of skins and seeds during maceration of four main italian red wine grape varieties

Red grape varieties are characterized by different phenolic contents (prominently tannins and anthocyanins) found in skins and seeds. The extractability of these compounds varies during maceration, as well as the mechanical properties of skins and seeds. Four main Italian red winegrape varieties were tested to understand these differences during a simulated maceration process

Interactional leader -follower sensorimotor communication strategies during repetitive joint actions

Non-verbal communication is the basis of animal interactions. In dyadic leaderfollower interactions, leaders master the ability to carve their motor behaviour in order to 'signal' their future actions and internal plans while these signals influence the behaviour of follower partners, who automatically tend to imitate the leader even in complementary interactions. Despite their usefulness, signalling and imitation have a biomechanical cost, and it is unclear how this cost-benefits trade-off is managed during repetitive dyadic interactions that present learnable regularities. We studied signalling and imitation dynamics (indexed by movement kinematics) in pairs of leaders and followers during a repetitive, rule-based, joint action. Trial-by-trial Bayesian model comparison was used to evaluate the relation between signalling, imitation and pair performance. The different models incorporate different hypotheses concerning the factors (past interactions versus online movements) influencing the leader's signalling (or follower's imitation) kinematics. This approach showed that (i) leaders' signalling strategy improves future couple performance, (ii) leaders used the history of past interactions to shape their signalling, (iii) followers' imitative behaviour is more strongly affected by the online movement of the leader. This study elucidates the ways online sensorimotor communication help individuals align their task representations and ultimately improves joint action performance

Evaluating the relative contributions of copying and reconstruction processes in cultural transmission episodes

The ability to transmit information between individuals through social learning is a foundational component of cultural evolution. However, how this transmission occurs is still debated. On the one hand, the copying account draws parallels with biological mechanisms for genetic inheritance, arguing that learners copy what they observe and novel variations occur through random copying errors. On the other hand, the reconstruction account claims that, rather than directly copying behaviour, learners reconstruct the information that they believe to be most relevant on the basis of pragmatic inference, environmental and contextual cues. Distinguishing these two accounts empirically is difficult based on data from typical transmission chain studies because the predictions they generate frequently overlap. In this study we present a methodological approach that generates different predictions of these accounts by manipulating the task context between model and learner in a transmission episode. We then report an empirical proof-of-concept that applies this approach. The results show that, when a model introduces context-dependent embedded signals to their actions that are not intended to be transmitted, it is possible to empirically distinguish between competing predictions made by these two accounts. Our approach can therefore serve to understand the underlying cognitive mechanisms at play in cultural transmission and can make important contributions to the debate between preservative and reconstructive schools of thought