1st cohort (2015-2018)

Project 1) Infant-driven learning from different kinds of social signals (Nivedita Mani, Tanya Behne & Julia Fischer)

Even very young infants show a preference for listening to certain kinds of social signals as opposed to others, e.g., infant-directed speech relative to adult-directed speech. Here, we examine the extent to which such early preferences influence infants' language acquisition, i.e., the extent to which infants drive language acquisition via their selective attention to different social signals. A further aspect of this project aims to understand why infants show such preferences and the extent to which such preferences and their implications for language development are driven by the language environment of individual children. Against this background, we will examine whether infants' selective attention can be attributed to the quality and quantity of prior language experience, the context in which information is presented and whether it will, in turn, impact learning success. Eye-tracking methods and the recording of event-related potentials will be available for the PhD candidate to investigate the study questions.

Project 2) The development of communicative signals in sign languages and gesture (Markus Steinbach & Nivedita Mani)

The visual-gestural modality of sign languages offers the unique property of directly integrating gestures into the grammatical system. Therefore, gestures used in social interactions by hearing non-signers may become incorporated into the linguistic system of sign languages. The analysis of the gesture-sign interface thus provides a unique opportunity to study the gestural evolution of a linguistic system. With this project, we want to focus both on the empirical description and theoretical analysis of social, communicative, and grammatical functions gestural elements express in sign and spoken languages. For this aim, data shall be obtained from deaf native signers and hearing non-signers; the annotation tools FACS and ELAN are available for further data annotation. In a theoretical part, selected theoretical models to analyze the incorporation of (grammaticalized) communicative and social signs into the grammatical system of sign languages shall be evaluated and extended.

Project 3) Neuro-cognitive mechanisms of audio-visual integration in emotion communication (Annekathrin Schacht)

Humans use a wide range of means to express their emotions, both in the verbal and the non-verbal domain (facial, bodily, or vocal cues and signals). Although there is evidence that emotion recognition is facilitated the more channels are provided, it is yet unsolved under which boundary conditions receivers integrate all of these cues. Within this project, we want to investigate the processing of multi-modal emotion information in simulated situations of dyadic communication. We aim to specify the relative relevance of emotion cues (facial, prosodic) that are transmitted through different sensory channels (visual, auditory) and their impact on emotion decoding and subsequent information processing. A multi-measure approach will be used to obtain data on individuals' performance, event-related brain potentials, and peripheral physiological indicators.

Project 4) Effects of testosterone reactivity on plastic personality signaling and its social monitoring in humans (Lars Penke, Julia Ostner & Oliver Schülke)

In this project, we like to study the endocrinological base of personality plasticity, social signaling and social monitoring using testosterone reactivity as an example. Across species, free testosterone levels have been linked to behavioral differences in competitiveness vs. nurturance, and social signaling of threat and courtship displays. In humans, reactive testosterone increases can be elicited in the lab by intra-sexual competition, status challenges, and the presence of opposite-sex observers. Within this project, the PhD candidate will have the opportunity to investigate which personality aspects predict testosterone reactivity to competition and status challenge and whether momentarily increased testosterone is socially signaled in perceivable behavioral cues. Another question of this project is if increased testosterone does affect social perceptions relative to the receivers' hormonal status. For this purpose, possible tools will be endocrinological analyses as well as personality assessments and behavioral observations.

Project 5) The role of partners' personalities for close affiliative relationships (Oliver Schülke, Julia Ostner & Lars Penke)

Close affiliative relationships can be construed as naturally selected adaptations to group life. Like human friendships, close affiliative relationships evolved as alliances generating adaptive benefits via support in critical situations. Partner predictability or trust is crucial for coordinated action in risky situations and can be increased by choosing self-similar personalities for the formation of close relationships. Although it is well established that a human's personality affects relationships, it is less clear whether and how similarity in personality plays a role in the formation and in the maintenance of dyadic affiliative relationships in nonhuman primates. In this project, we want to investigate whether and how the strength of dyadic affiliative relationships is linked to the partners' similarity in personality in wild male Assamese macaques. For the data collection, the PhD candidate will work at our long term field site in Phu Khieo, Thailand, where personality assessments, behavioral observations and play-back experiments can be conducted.

Project 6) The quality of affiliative social relationships and endogenous oxytocin (Julia Ostner & Oliver Schülke)

The neuropeptide oxytocin facilitates the development of interpersonal trust and prosociality as well as social categorization of others into in-group vs. out-group. Thus, oxytocin enhances the formation of affiliative and cooperative social relationships and at the same time it promotes defensive aggression and out-group competition. Studies investigating this dual function in ecologically valid natural settings are largely lacking. The focus of this project on non-human primates will be on the dual role of oxytocin in male coalitions and in the initial formation and subsequent maintenance of affiliative social relationships. For this purpose, the PhD candidate will combine behavioral observations and non-invasive analysis of endogenous urinary oxytocin and stress hormones in Barbary macaques.

Project 7) Social monitoring in a multi-level primate society (Julia Fischer)

Recent theoretical considerations under the umbrella of the "Social Brain hypothesis" suggest that life in fission-fusion societies is cognitively particularly demanding. Alternatively, strong competition may be a more important driver than social complexity. With this project, we aim to contribute to this debate by studying the social knowledge of free-ranging, individually identified Guinea baboons, which live in a complex multi-level society with high degrees of tolerance. The PhD candidate will have the opportunity to conduct behavioral observations and playback experiments at our long-term field site in Simenti, Senegal. Additionally, comparative data from other baboon taxa are available allowing for an integration of study result into the broader context.

Project 8) Statistical learning and social inferences in human children and nonhuman primates (Hannes Rakoczy & Julia Fischer)

Arriving at general conclusions regarding one's conspecifics on the basis of sparse and noisy data is one of the big challenges of social inductive learning. Recent developmental work has shown that social inferences and selective learning emerges in the preschool years, but the cognitive foundations and relations to other cognitive capacities (in particular, nascent intuitive-statistical reasoning and learning) are unclear. Recent comparative work found that intuitive statistics are present in nonhuman primates, but nothing remotely comparable to the systematic selective learning found in human children has been documented so far. We aim to investigate whether monkeys show selective social learning and what the functional relations to intuitive statistics are. For this purpose, the PhD candidate will have the opportunity to carry out direct comparative analyses of children's and monkey's cognitive performances by conducting experiments at the German Primate center with a group of long-tailed macaques and at the "Kindsköpfe" lab.

Project 9) Learning from reliable and unreliable speakers (Tanya Behne & Nivedita Mani)

Human learning and development is characterized by the cultural transmission of knowledge from one individual to the next. Especially in the case of opaque knowledge, e.g., where it is not immediately clear what a new word refers to, or what one should do with a new tool, novice learners need to monitor the reliability and accuracy of others to choose whom to learn from. Recent evidence suggests that children from about 4 years are selective in whom they learn novel words and practices from. Against this background, we aim to explore the early origin of selective social learning and its cognitive underpinnings. With this project, we want to investigate young infants' word learning from reliable and unreliable speakers. The PhD candidate will have the opportunity to use event-related potential experiments to examine the neurophysiological correlates of speaker-reliability and eye-tracking-based methods to study infants' eye-movements and pupil dilation.

Project 10) The ontogeny of individual and collective advice-taking (Hannes Rakoczy, Stefan Schulz-Hardt & Thomas Schultze)

Social belief revision in the form of advice-taking is well studied in adult social psychology. Adults do take others' advice systematically and selectively, but are far from behaving optimally. The development of selective belief formation (selective trust and learning) has been intensively investigated in recent years, yet its cognitive basis remains unclear. In addition, basically nothing is known to date about the development of selective belief revision in children. With this project, we would like to systematically investigate the ontogenetic roots of advice-taking by using the standard judge-adviser paradigm adapted for children. For this purpose, the PhD candidate will conduct experiments in our well established "Kindsköpfe" lab.

Project 11) Emergence of leadership: Predicting leadership initiative and followership from individual traits and behavioral styles (Stefan Schulz-Hardt & Andreas Mojzisch)

Research on emergence of leadership seeks to identify the factors that determine who will become leader in a group. A key idea of the present project is that variables that decide about whether or not a particular group member will attempt to lead a group (i.e., leadership initiative) need not be identical with those variables that affect the success of such attempts (i.e., followership). With this project, we aim to determine the influence of various individual difference variables on leadership initiative on the one hand and followership on the other hand in interactive group settings. For this purpose, the PhD candidate will have the opportunity to assess a large set of individual predictors, including individuals' risk preference, physical size as well as testosterone and estradiol levels and to study individuals' behavioral styles.

Project 12) Group coordination and leadership in Guinea baboons (Dietmar Zinner & Julia Fischer)

The benefits of group living can be achieved only if the group members synchronize and coordinate their activities and movements despite possible divergent interests. Studies on group coordination in nonhuman primates suggest that collective behavior does not emerge just through self-organizing processes, but that more complex planning, communication and coordination is invoked. Furthermore, decision making almost always involves some form of leadership, e.g., particular individuals may initiate and lead group movements more often than others. Studies on group coordination in baboons revealed apparently contradictory results. This project gives the opportunity to investigate patterns and processes regarding collective decision-making in the context of group movements in Guinea baboons, who live in a multi-level society. The PhD candidate will conduct behavioral observations at our long term field site Simenti, Senegal.

funded by the