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  • Print publication year: 2010
  • Online publication date: June 2012

17 - Molecular and genetic influences on the neural substrate of social cognition in humans



Human social behaviour is wonderfully complex, and influenced by manifold effects including genetic, environmental and cultural factors (Chapter 15). Here we focus on one aspect of human social behaviour: social cognition. Human social cognition, or the ability to process social information thus influencing human social behaviour, is a broad and complex concept, as yet not defined unambiguously. The aim of this chapter is to introduce the basic neural processes underlying human social cognition, and the genetic and molecular influences that may shape behavioural variation between individuals. To this end, we describe the neural circuits in the brain underlying social cognition, particularly with reference to self-knowledge and the concept of theory of mind – the ability to think about things from the perspective of another. Cellular aspects of social cognition, although still unclear, are explored in relation to the putative role of mirror neurons. The neurobiology of attachment underlying social relationships aids the discussion of the molecular underpinnings of social cognition with particular reference to neuropeptides: oxytocin and vasopressin. Oxytocin and vasopressin are nonapeptides that have been increasingly identified as playing a pivotal role in social cognition. Animal studies have highlighted the role of these peptides in social roles as diverse as parenting behaviour, social recognition and affiliative behaviours (Chapter 11). Here we discuss the evidence implicating these neuropeptides in humans. Moreover, it is increasingly recognised in animal studies that the processes of social cognition are supported by reward circuitry, underpinned by the dopaminergic neurotransmitter system in the brain.

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