People with Parkinson’s disease are less likely to make certain kinds of mistakes – those that happen when we are “on autopilot”. The surprising finding helps support a new theory about the condition’s root causes in the brain.

Parkinson’s disease is a progressive condition causing slowness, difficulties in moving and tremors. It involves the death of brain cells , especially those that make the signalling molecule dopamine.

In 2010, Peter Redgrave at the University of Sheffield, UK, and …