Recent & Upcoming Talks

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.

Human social learning is a foundational component of culture. From observing and replicating the behaviours of others we can build on and develop what others have done before to generate new and innovative cultural artefacts. This process of cultural transmission has been studied in laboratory settings for some time. However, this literature has often treated transmission events as indivisible units rather than as joint actions, focussing only on imitation or emulation of single behaviour episodes transmitted in a purely passive way. We present an experiment that aims to bridge the literatures of cultural transmission and joint action, by testing the effect that a pedagogical transmission context (Demonstration) has on learning a musical sequence, compared with a non-pedagogical context (Performance). Models adapt their behaviour during Demonstrations using kinematic modulations associated with pedagogy (slowing down, exaggerating movements) that are observed by a learner but not intended to be replicated. We show that with more sophisticated measures of actions during learning and teaching we can go beyond judging transmission episodes on how similar a reproduction is to a model, and instead look at how communicative and pragmatic signals in the model are received and integrated.

Individuals have a drive towards maximising action efficiency – given a choice of two actions to achieve the same goal, they will choose the action that incurs fewest costs. In joint actions, actors prioritise joint efficiency or co-efficiency, maximising the utility of the joint action even if this comes at a cost to themselves. However, when acting jointly it may also be important to consider factors other than efficiency, such as fairness. We investigate whether the reputational motivation to be seen as fair will interfere with participants’ drive to maximise co-efficiency. We present the results of two experiments where participants complete the first part of a two-step joint action with a partner and have to decide between a fair action that requires equal contribution from both agents, and an unfair action that disadvantages either themselves or their partner. Participants consistently and reliably act in a way that maximises co-efficiency regardless of fairness or the costs that they incur individually, but they also take longer to perform actions that are unfair to their partner (rather than themselves). This suggests that although participants are sensitive to (un)fairness in task distribution they do not let this affect their decisions.

In joint actions, individual actors prioritise the efficiency of the joint action even if this means being individually inefficient. However, it is not known whether fairness plays a role in these decisions. We present a paradigm that explores whether participants prioritise efficiency when efficient options require unfair task distributions.

People in a distrust mindset find alternative solutions to problems that often involve using unexpected strategies. This poses a problem for coordination, where two people must predict each other’s actions to achieve a consensus. We present a series of experiments looking at the role of distrust in coordinated decision-making.

Self-relevant information is subject to privileged processing over information related to other people. Object ownership is a way of making otherwise neutral objects self-relevant, and therefore giving these items access to the same privileges as other self-relevant stimuli. Previous research has shown that object ownership effects (faster processing of self-owned over other-owned items) are reliable and consistent across a range of tasks. One dimension of ownership that has yet to be explored, however, is the role of territory. We know that space and territory play a role in terms of the physical environment – people show privileged processing for items that are accessible to them (peripersonal space; Constantini et al., 2011) – but we can also conceptualise territory in more abstract terms. For example, you do not need to be physically present in your own house for it to be your house. The question is, does territory affect processing even when it is an abstract, arbitrary compartmentalising of space that does not impact physical affordances? And how does ownership of territory interact with ownership of objects? We explore how territory affects ownership effects in an adapted trolley-sorting paradigm. Participants sort items that belong to them or to another person into relevant baskets or trolleys. The key manipulation is that items can appear in a territory belonging to the self or to the other. Across three experiments we find that territory does affect ownership effects, as the privileged processing of self-owned items disappears when those items appear in another’s territory. This indicates that people are not just responding to the ownership status of items in a universal way, but are taking into account how these items are embedded within the social environment.

Even from early childhood, humans have a sense of fairness. Unfair players are judged harshly and people expect those who shirk effort at the expense of others to be punished, not rewarded. As adults, there is also a reputational motivation to be seen as fair, and people prefer to continue interactions with fair interaction partners rather than unfair ones. However, to date these studies have examined fairness in a third-party perspective: they often look at how people judge other people’s fairness in relation either to themselves or to other people. These studies have also focussed on resource or reward distribution in response to fair or unfair behaviour. There is little research looking at how and whether people choose to be fair themselves when they are responsible for task distribution. It is also unclear whether a desire to be fair could compete with other motivations in joint tasks, namely efficiency. Previous research has shown that interactants show a strong drive towards maximising the overall efficiency of joint actions (co-efficiency), even when this means sacrificing the efficiency of their individual actions. In the present study, participants completed a task where they were passing objects on a screen to a virtual partner whom they believed to be a real person in a different room. Participants could choose to pass the object at one of two points – one that was equidistant between the origin and target site, meaning that both actors would contribute the same effort in moving the item (fair) and one where the passing site was closer to either the origin or target (unfair). The unfair route could be either longer overall than the fair route (fairness and co-efficiency are congruent), shorter overall (fairness and co-efficiency are incongruent), or the same length (equal trials). We find that people show a strong drive towards maximising co-efficiency, choosing the shortest overall path even when this disadvantages themselves, but little evidence for a drive towards fairness. On equal trials, participants show evidence of altruism in their decisions, often choosing the route that minimises the contribution of their partner when this does not compromise the overall co-efficiency. As such, it is not that participants behave selfishly during interactions, but that they do not have a drive to ensure a fair task distribution on a trial-by-trial basis. Instead, they choose to be efficient as a group.

If they have to meet a stranger somewhere in Paris tomorrow at noon, most people would go to the Eiffel Tower as the landmark’s saliency creates a natural focal point. However, there are many landmarks in Paris and these can be more or less salient to different individuals. How does a person know that the landmark they find the most salient is the same that the stranger finds most salient? In this study we use an adapted Schelling-point coordination game with three levels of item saliency (high, medium, and low) to see how people coordinate under cases of such ambiguity. We compare the choices of people who were instructed to make individual decisions about saliency (n=188; 199) with people who were instructed to coordinate their decisions with a partner (n=188; 197). Counterintuitively, we find that participants who intentionally coordinate show lower agreement on items than those who make individual decisions. While making decisions based on individual feelings of saliency is the most effective coordination strategy in the current task, intentionally coordinating participants sometimes use alternative strategies that paradoxically compromise coordination success. This raises a compelling avenue for further study to explore how and why coordinated decision making fails.

The face inversion effect is typically used to show that faces are processed holistically – when a face is presented upside down it disrupts the perception of identity, expression and eye gaze, even though low-level perceptual features of the image are preserved. We used the inversion effect to investigate how participants perceive the relationship between individual faces. We presented participants with pairs of faces that either looked towards each other (socially engaged) or away from each other (disengaged). We then asked participants to judge where the faces were looking. When the pairs of faces were inverted judgement of engaged pairs was significantly impaired (compared with upright), but the same impairment was not found for inverted disengaged pairs. This selective impairment for engaged pairs suggests that mutual gaze leads to dyads being perceived as perceptual units rather than pairs of discrete individuals.

People in groups frequently coordinate their actions with others to produce joint actions – even when such joint actions incur motor costs with no clear goal (e.g. a Mexican wave at a football match) – and this is likely done to increase one’s sense of group cohesion, affiliation, and social connection with other actors (Hove & Risen, 2009; Marsh, Richardson, & Schmidt, 2009). One example of joint action is joint speech (found in many religious and cultural practices; e.g. communal prayer, the United States Pledge of Allegiance, or chanting at a football match), which unlike other instances of joint action can vary in terms of semantic content. That is, in addition to the prosocial consequences of performing in synchrony, joint speech may have the additional effect of manipulating participants’ beliefs or attitudes related to what is being said. We present preliminary work that explores this, where participants read true and false factual statements aloud either individually or as a pair, and made individual and joint decisions about their veracity. We find no evidence that joint speech production influences participants’ beliefs about statement veracity, suggesting that the cognitive consequences of joint speech production have limited effect on epistemic evaluations.

People can use their eyes to direct others’ attention towards objects and features in their environment. A person who consistently looks away from targets is later judged to be less trustworthy than one that consistently looks towards targets, even when the person is a background distractor that viewers are instructed to ignore. This has been shown in many experiments using trustworthiness ratings, but one outstanding question is whether these systematic changes in trustworthiness reflect perceptual distortions in the stored memory representations of these faces, such that faces that provide valid cues are remembered as looking more trustworthy than they actually were, and vice versa for invalid faces. We test this in two experiments, one where we gave participants the opportunity to morph the faces along a continuum of trustworthiness and asked them to report the image they had seen during the experiment, and one where we presented the original face images morphed to appear more or less trustworthy and asked participants to select from the two. The results of these two experiments suggest that this incidental learning of gaze contingencies does not result in distorted memory for the faces, despite robust and reliable changes in trustworthiness ratings.

People can use their eyes to direct others’ attention towards objects and features in their environment. A person who consistently looks away from targets is later judged to be less trustworthy than one that consistently looks towards targets, even when the person is a background distractor that viewers are instructed to ignore. This has been used in previous research to experimentally manipulate the trustworthiness of gaze-cueing faces. However, to date, evidence remains unclear as to how the identity of a cueing face may affect how we interpret trustworthiness from gaze cues. Social psychology has long known that we treat people differently on the basis of social groups, and to date, no studies have investigated whether real-world social groups can affect the incidental learning of trust from gaze cues. As in-group members are typically favoured over out-group members, one might expect that invalid in-group faces would be more resilient to devaluation than out-group faces. Alternatively, in-group members are treated as more heterogeneous individuals than are out-group members, and in-group transgressors can sometimes be punished more harshly than out-group transgressors, so one might expect that this would lead to stricter penalties applied to invalid in-group identities. We explore this by using the real-world social category of race, where participants see faces of both their own and another race, half of which provide valid cues and half invalid. We provide the first investigation into whether these real-world differences in the face identities change how participants learn about trust from patterns of gaze behaviour.

In everyday interactions we find our attention follows the eye gaze of faces around us. As this cueing is so powerful and difficult to inhibit, gaze can therefore be used to facilitate or disrupt visual processing of the environment, and when we experience this facilitation or disruption ourselves we infer information about the cueing face, specifically manifesting in judgements of trustworthiness. However, to date no studies have investigated how resilient these impressions are to interference, or how long they last. To explore these questions we used a gaze-cueing paradigm where 16 faces demonstrated either valid (always cueing the correct location) or invalid (always cueing the incorrect location) cueing behaviours. Previous experiments using this paradigm show that valid faces are subsequently rated as more trustworthy than invalid faces. In answer to the first question we show, when introducing a short interference task between gaze-cueing and trustworthiness ratings, this effect is extinguished. However, if the face identities are initially encoded deeply this enables more stable learning of the association between identity and gaze patterns. Addressing the second question we find the effect is weaker but that the overall pattern of results.