“The mystery behind Agatha Christie’s enduring popularity may have been solved by three leading universities collaborating on a study of more than 80 of her crime novels.

Despite her worldwide sales of two billion, critics such as the crime writer P D James pan her writing style and “cardboard cut-out” characters. But the study by neuro-linguists at the universities of London, Birmingham and Warwick shows that she peppered her prose with phrases that act as a trigger to raise levels of serotonin and endorphins, the chemical messengers in the brain that induce pleasure and satisfaction.” – (Sunday Times of London)