What is the connection between the cultural evolution of a language and the rapid processing response to that language in the brains of individual learners? In an iterated communication study that... Show moreWhat is the connection between the cultural evolution of a language and the rapid processing response to that language in the brains of individual learners? In an iterated communication study that was conducted previously, participants were asked to communicate temporal concepts such as “tomorrow,” “day after,” “year,” and “past” using vertical movements recorded on a touch screen. Over time, participants developed simple artificial ‘languages’ that used space metaphorically to communicate in nuanced ways about time. Some conventions appeared rapidly and universally (e.g., using larger vertical movements to convey greater temporal durations). Other conventions required extensive social interaction and exhibited idiosyncratic variation (e.g., using vertical location to convey past or future). Here we investigate whether the brain's response during acquisition of such a language reflects the process by which the language's conventions originally evolved. We recorded participants' EEG as they learned one of these artificial space-time languages. Overall, the brain response to this artificial communication system was language-like, with, for instance, violations to the system's conventions eliciting an N400-like component. Over the course of learning, participants' brain responses developed in ways that paralleled the process by which the language had originally evolved, with early neural sensitivity to violations of a rapidly-evolving universal convention, and slowly developing neural sensitivity to an idiosyncratic convention that required slow social negotiation to emerge. This study opens up exciting avenues of future work to disentangle how neural biases influence learning and transmission in the emergence of structure in language. Show less
Humans attend to others’ facial expressions and body language to better understand their emotions and predict goals and intentions. The eyes and its pupils reveal important social information.... Show moreHumans attend to others’ facial expressions and body language to better understand their emotions and predict goals and intentions. The eyes and its pupils reveal important social information. Because pupil size is beyond voluntary control yet reflective of a range of cognitive and affective processes, pupils in principal have the potential to convey whether others’ actions are interpreted correctly or not. Here, we measured pupil size while participants observed video-clips showing reach-to-grasp arm movements. Expressors in the video-clips were playing a board game and moved a dowel to a new position. Participants’ task was to decide whether the dowel was repositioned with the intention to be followed up by another move of the same expressor (personal intention) or whether the arm movement carried the implicit message that expressor’s turn was over (social intention). Replicating earlier findings, results showed that participants recognized expressors’ intentions on the basis of their arm kinematics. Results further showed that participants’ pupil size was larger when observing actions reflecting personal compared to social intentions. Most interestingly, before participants indicated how they interpreted the observed actions by choosing to press one of two keys (corresponding to the personal or social intention), their pupils within a split second, had already given away how they interpreted the expressor’s movement. In sum, this study underscores the importance of nonverbal behavior in helping social messages get across quickly. Revealing how actions are interpreted, pupils may provide additional feedback for effective social interactions. Show less
We argue that stimulus uncertainty induces a cognitive state that can be linked to a concept that has been formerly described as ‘curiosity’ (Berlyne, 1949) – a state that motivates the agent to... Show moreWe argue that stimulus uncertainty induces a cognitive state that can be linked to a concept that has been formerly described as ‘curiosity’ (Berlyne, 1949) – a state that motivates the agent to reduce the uncertainty by exploring it. In two attention filtering tasks we varied response compatibility and stimulus congruency. In addition, we manipulated whether stimulus congruency was predictable or random. In conditions with random presentation the impact of congruency on compatibility was more pronounced suggesting that stimulus congruency was processed more strongly in a random environment. While this makes no sense from a short term strategic perspective in the laboratory, this allocation of attention to uncertain stimulus conditions makes perfect sense outside the laboratory. The impact of uncertainty on attentional control should not be considered a leakage but rather an investment into possible future opportunities. Show less
Cognitive control requires a balance between persistence and flexibility. We studied inter- and intraindividual differences in the metacontrol bias towards persistence or flexibility in cognitive... Show moreCognitive control requires a balance between persistence and flexibility. We studied inter- and intraindividual differences in the metacontrol bias towards persistence or flexibility in cognitive search tasks from various cognitive domains that require continuous switching between persistence and flexibility. For each task, clustering and switching scores were derived to assess persistence and flexibility, respectively, as well as a total performance score to reflect general performance. We compared two, not mutually exclusive accounts according to which the balance between clustering and switching scores is affected by (1) individual, trait-like metacontrol biases towards persistence or flexibility and/or (2) the metacontrol adaptivity to bias states according to changing situational demands. We found that clustering and switching scores failed to generalize across tasks. However, clustering and switching were inversely related and predicted the total performance scores in most of the tasks, which in turn partially generalized across tasks and task domains. We conclude that metacontrol-biases towards persistence or flexibility can be adapted easily to specific task demands and individual resources, possibly overwriting individual metacontrol trait biases. Moreover, we suggest that total performance scores might serve to measure metacontrol adaptivity in future studies if task-restrictions and resources are known and/or well balanced. Show less
Studies on joint task performance have proposed that co-acting individuals co-represent the shared task context, which implies that actors integrate their co-actor’s task components into their own... Show moreStudies on joint task performance have proposed that co-acting individuals co-represent the shared task context, which implies that actors integrate their co-actor’s task components into their own task representation as if they were all their own task. This proposal has been supported by results of joint tasks in which each actor is assigned a single response where selecting a response is equivalent to selecting an actor. The present study used joint task switching, which has previously shown switch costs on trials following the actor’s own trial (intrapersonal switch costs) but not on trials that followed the co-actor’s trial (interpersonal switch costs), suggesting that there is no task co-representation. We examined whether interpersonal switch costs can be obtained when action selection and actor selection are confounded as in previous joint task studies. The present results confirmed this prediction, demonstrating that switch costs can occur within a single actor as well as between co-actors when there is only a single response per actor, but not when there are two responses per actor. These results indicate that task co-representation is not necessarily implied even when effects occur across co-acting individuals and that how the task is divided between co-actors plays an important role in determining whether effects occur between co-actors. Show less
A central issue in the study of joint task performance has been one of whether co-acting individuals perform their partner’s part of the task as if it were their own. The present study addressed... Show moreA central issue in the study of joint task performance has been one of whether co-acting individuals perform their partner’s part of the task as if it were their own. The present study addressed this issue by using joint task switching. A pair of actors shared two tasks that were presented in a random order, whereby the relevant task and actor were cued on each trial. Responses produced action effects that were either shared or separate between co-actors. When co-actors produced separate action effects, switch costs were obtained within the same actor (i.e., when the same actor performed consecutive trials) but not between co-actors (when different actors performed consecutive trials), implying that actors did not perform their co-actor’s part. When the same action effects were shared between co-actors, however, switch costs were also obtained between co-actors, implying that actors did perform their co-actor’s part. The results indicated that shared action effects induce task-set sharing between co-acting individuals. Show less
