The role of socio-cognitive and emotional impairments in young children with emerging symptoms of neurodevelopmental disorders

Symptoms of neurodevelopmental disorders (NDDs) that are established in early childhood often exacerbate, if left untreated, and continue into adulthood. There is increasing evidence that underlying socio-cognitive and emotional processes contribute to the development, persistence and severity of NDDs. Theory of mind (ToM), empathy and facial mimicry, in particular are thought to play a causal role in the development of psychopathology. Based on this, it is possible that early ToM, empathy and facial mimicry assessment may help to identify risk for future NDDs. However, research has not yet explored their roles in young, pre-diagnostic children at risk of developing NDDs. Having a better understanding of the processes and mechanisms underlying symptoms of NDDs early in childhood will lead to the development of early interventions that promote a more positive developmental trajectory. Chapters 2, 3 and 5 of this thesis aimed to examine the roles of socio-cognitive and emotional processes in children with early signs of NDDs and understand how they relate to specific emotional and behavioural problem profiles. More specifically, Chapter 2 examined ToM in children with broad-ranging symptoms of NDDs compared to TD controls; Chapter 3 compared ToM and empathy in those with high levels of anxiety compared to those with low levels of anxiety and explored their relationships with anxiety severity; and Chapter 5 examined the role of facial mimicry in children’s peer relations by comparing facial mimicry responses in those with and without peer problems and exploring its relationship with peer problem severity. Given the causal role an impairment in facial mimicry is thought to play in empathic responding, Chapter 4 investigated the relationship between facial mimicry and cognitive and affective empathy. We found that ToM, empathy, and facial mimicry are all important processes that are implicated in the development, and explain variation in, severity of symptoms of NDDs. In addition, we found that ToM was differentially affected across different symptom clusters; while low levels of cognitive ToM were associated with broad-ranging symptoms of NDDs, high levels of cognitive ToM were specifically related to anxiety symptomatology. Finally, we demonstrated that facial mimicry for sadness was positively related to children’s ability to understand and experience other people’s sadness, suggesting that impaired facial mimicry may be responsible for the impaired empathic responding for negative emotions demonstrated by children with psychopathology. This thesis suggests that interventions targeting children’s ToM, empathy and facial mimicry should be considered as a preventative effort to reduce risk for NDDs before the onset of clinical symptoms and significant maladjustment