Planning and social interaction improve into our twenties

12 October 2006

Teenagers who believe that they can tidy their bedroom in three minutes and finish their homework in another five might not be wilfully slapdash. New research from Suparna Choudhury (UCL Institute of Cognitive Neuroscience and UCL Institute of Child Health) has found that our ability to imagine our actions accurately improves throughout adolescence and well into our twenties, with possible repercussions for the way we interact socially.

In the first study to focus on how adolescents develop the capacity to envisage actions, Ms Choudhury found that adults and adolescents completed simple tasks – such as repeatedly drawing a figure of eight within parallel lines – in similar timeframes.  However, when asked only to imagine the process of completing the tasks, or ‘internally model’ them, adolescents were found to be poorer at estimating how long they would take.

“The research demonstrates that the ability to plan our actions continues to develop during adolescence. This could be because the parietal cortex – the part of the brain thought to be responsible for this function – is still maturing during adolescence,” explained Ms Choudhury, a PhD student.

Adults with damage to the parietal cortex often struggle with fine motor control and have difficulties in accurately imagining, or internally modelling, their actions. Recent brain imaging studies have shown that the parietal cortex is one of the last areas to develop in the human brain, and that it undergoes particular development during adolescence.

The research, published in the journal ‘Neuropsychologia’, emphasises that imagining one’s actions is not only important to planning, but may also relate to social cognitive functions such as empathy: we relate to other people’s views and empathise with them by simulating their actions in our minds. Ms Choudhury’s next piece of research will concentrate exclusively on how autistic people internally ‘model’ tasks.