Development of the social brain in adolescence

Abstract

The brain has evolved to understand and interact with other people. We are increasingly learning more about the neurophysiological basis of social cognition and what is known as the social brain, that is the network of brain regions involved in understanding others. This paper focuses on how the social brain develops during adolescence. Adolescence is a time characterized by change - hormonally, physically, psychologically and socially. Yet until recently this period of life was neglected by cognitive neuroscience. In the past decade, research has shown that the brain develops both structurally and functionally during adolescence. Large-scale structural MRI studies have demonstrated development during adolescence in white matter and grey matter volumes in regions within the social brain. Activity in some of these regions, as measured using fMRI, also shows changes between adolescence and adulthood during social cognition tasks. I will also present evidence that theory of mind usage is still developing late in adolescence. Finally, I will speculate on potential implications of this research for society.

Figure 1

A section of the dorsal MPFC that is activated in studies of mentalising: Montreal Neurological Institute (MNI) ‘y’ coordinates range from 30 to 60, and ‘z’ coordinates range from 0 to 40. Dots indicate voxels of decreasing activity during seven mentalising tasks between late childhood and adulthood.^, The mentalising tasks ranged from understanding irony, which requires separating the literal from the intended meaning of a comment, thinking about one's own intentions, thinking about whether character traits describe oneself or another familiar other, watching animations in which characters appear to have intentions and emotions, and thinking about social emotions such as guilt and embarrassment

Figure 2

a, b. Images used to explain the Director condition: participants were shown an example of their view (a) and the corresponding director's view (b) for a typical stimulus with four objects in occluded slots that the director cannot see (e.g. the apple); c, d. Example of an experimental (c) and a control trial (d) in the Director condition. The participant hears the verbal instruction: ‘Move the small ball left’ from the director. In the experimental trial (c), if the participant ignored the director's perspective, she would choose to move the distractor ball (golf ball), which is the smallest ball in the shelves but which cannot be seen by the director, instead of the larger ball (tennis ball) shared by both the participant's and the instructor's perspective (target). In the control trial (d), an irrelevant object (plane) replaces the distractor item