Why are we social? Mapping the development of social motivation through adaptive sampling

Babies are born with a drive to interact with other people. Within a year, this drive takes them from a passive newborn to a smiling, talking toddler. Our goals shape how sociable we are and who we socialise with across the lifespan, and are thus fundamental to social psychology (Over, 2016). However, the reasons why babies choose to interact remains a mystery. Measuring motivation is difficult because it is generated by the child, whilst traditional experimental methods measure passive responses to stimuli produced by the experimenter. Our transformative approach to studying infant social motivation is inspired by innovations in advertising. In the last twenty years, advertising has been revolutionised by the use of artificial intelligence (AI). Rather than the traditional model of creating generic campaigns based on what creatives thought consumers wanted, on the internet advertisers can now identify what exactly motivates individual customers by trying out different adverts and measuring an individual customer's reaction to them. For example, if you click on an advert for a holiday in Mauritius, you will then see adverts for holiday resorts on other websites that you later visit. We aim to use the principles of this approach to determine what motivates babies to interact with other people.
Study 1: Identify brain signals and networks related to social motivation. As a first step, we need to identify readouts of core social reward networks in the brain; measuring the brain (rather than behaviour) allows us to measure social motivation using the same signals across development. We can measure these networks very precisely using functional magnetic resonance imaging (fMRI), but this isn't suitable for babies who are awake. Functional Near-Infrared Spectroscopy (fNIRS) is an alternative imaging method that is very similar to fMRI but that can be used with babies who are awake. We will use a combination of fNIRS and fMRI to identify brain signals of the brain networks that are involved in the core social reward networks, which we can then measure with fNIRS alone in Studies 2 and 3.
Study 2: Identify the social cues infants find maximally rewarding. We will use social tasks that use eye tracking methodology. This technology follows exactly where infants look at on a screen, with infants' looking behaviour even triggering visual events on the screen (e.g., if infants look towards a face, this will trigger a social reward such as a smiling or talking face). As the infant watches the screen and completes the tasks, the algorithm will be able to learn which tasks produce a larger brain signal from the social reward networks. This then allows us to determine which type of social interaction is particularly rewarding for the infants and how this may change as babies grow up. For example, very young babies may be particularly interested in eye gaze and smiling, but as they grow into toddlers and begin to talk, language may be more interesting for them.
Study 3: Develop tools for using our approach within real-life interaction. Screen based social tasks are extremely useful, but watching social stimuli on a screen is very different from the dynamic nature of interacting with people. Here, we will measure infants' brain responses whilst they interact with a social partner. As the infant interacts with their partner, the algorithm will identify the type of social cues that they find particularly rewarding. The algorithm will then prompt the trained social partner to engage in these maximally rewarding social interactions (such as eye contact, smiling or touch). This will provide a demonstration of how our tools can be used within a custom intervention design for children with conditions that affect social motivation, like autism.
Taken together, our work is designed to produce new tools to transform our understanding of why babies socialise with other people, and to help vulnerable children to reach their full potential.

Who will benefit from this research?
We anticipate our research will benefit a range of end users, including parents, clinicians, and companies who design educational and social scaffolds for infants and young children.

Caregivers and the wider public: How? Caregivers are fascinated by children's minds. Our project will create novel ways to show caregivers what a child wants when they interact. We will be able to share this information with caregivers to help them better understand infants and young children. Better insights into a child's mind can facilitate parent-child bonding and teaching strategies, and we will focus dissemination efforts on sharing this information with caregivers. Strategies to engage: We will work with Advisory Board members (including parents involved in our studies) to design a website and newsletter to inform caregivers about the progress of our research. Further, we will work with Dr Silvia Dalvit (CEO of BabyBrains, a company designed to provide neuroscience-informed caregiver education http://www.baby-brains.com/) to share information about our findings through the BabyBrains website, newsletter and online app. This platform is used by thousands of families to access scientifically rigorous information about infant development. We will also host an open house demonstration of our technology and share our findings at the Centre for Brain and Cognitive Development and other locations targeted at caregivers (e.g. Science Museum, Polka theatre Wimbledon), including presentations and hands-on trials. We will also publicise our work through our contacts with traditional and online media outlets. For example, the BabyLab newsletter reaches over 5000 families, and our BabyLab Twitter and Facebook accounts have over 3500 followers. Our previous work has been featured in outlets like the Times, Guardian, Evening Standard, BBC and ITV news and documentaries, and the BBC have recently commissioned a three-part series for BBC2 focused on our BabyLab. Thus, we anticipate having significant reach for our research findings.

Clinicians: How? Our framework would enable the development of interventions tailored to individual children who are struggling with social skills. Our tools will allow clinicians and educators to test what types of interaction, toys or environments could help boost social motivation in children who might struggle. These interventions could then be incorporated into at-home behavioural intervention strategies. Strategies to engage: Our Advisory Board will include clinical psychologists involved in developing interventions for young children. Project 3 will provide critical pilot data for future applications to develop these techniques. To ensure we reach this audience, we will host an outreach day for clinicians to develop future collaborations and funding plans. We will also present our findings at conferences attended by the clinical community, including the International Meeting for Autism Research and the British Psychological Society Division of Clinical Psychology section.

Educational toy manufacturers: How? Our work would also have a broad impact on manufacturers of educational toys, creating the potential for economic benefit. Our project will create new ways for toy companies to test whether toys designed to facilitate parent-child interaction are activating the brain systems that will prompt children to engage in motivated social behaviour. Strategies to engage: Advisory Board members from leading educational toy companies will advise us on a proof of principle study that will test the response of appropriate brain systems while children play with educational toys currently on the market. If successful, this will create the collaborative contacts and pilot data necessary for future applications for industrial funding.