PEOPLE'S self-esteem, their need to gain approval or avoid humiliation are psychological drivers that help fuel conflicts, and must be factored into attempts to bring about peace, an expert has said. Like most individuals, leaders of countries or armed groups may go to great lengths to protect their self-esteem, and this can make them deaf to reason, said Paul Randolph, a mediation expert at Regent's University London and author of a new book on the issue. He said fear of humiliation has played a significant part in prolonging Syria's conflict, which has entered its sixth year. A second round of peace talks to end the war that has killed up to 470,000 people is due to resume on Monday in Geneva. Negotiators are expected to tackle the issue of a political transition in Syria, including Syrian President Bashar Al-Assad's future. US Secretary of State John Kerry, who is working with Russia to persuade Assad to step down, said on Tuesday there was no way to end the Syrian war with Assad still at the helm. "It's a very, very complex situation there. But why leaders of nations will not step down is the same driver that prevents somebody from saying sorry ... it is a shame for them, and shame is painful," Randolph told the Thomson Reuters Foundation. Scientists have found that an attack on a person's self-esteem activates the same parts of the brain as physical pain, he said. "So when you're humiliated, your brain interprets it as if you're putting your finger in the fire ... our brain doesn't like it and it won't allow us to do it," he said. That, combined with the desire to make a mark on the world — another expression of self-esteem — makes it hard for leaders to retreat. "The last thing you want to leave is a mark that is a smudge. So it drives people to fight against all the odds just to protect and maintain their self-esteem," Randolph said. What is needed in Syria is a "golden bridge", a concept from ancient China, which advises any wise conquering general to build a golden bridge on which his defeated enemy can retreat, Randolph added. "All disputes are really very simple in the sense that it's about somebody wanting something and somebody else not being prepared to give it," said Randolph. Each side usually has both rational and psychological elements to them. So psychology has a huge part to play in understanding and resolving disputes, and getting the parties to shift their positions from a degree of intransigence to being collaborative, he added. Crucial to the process is for disputing parties to feel heard, which boosts their self-esteem. "One of the extraordinary things about mediation is that if the parties feel heard, their anger subsides," Randolph said. That is when logic and reason can begin, and through negotiation the needs of both sides can be addressed. The aim is to end up with no winner or loser, but with both sides gaining, he said. Randolph's book "The Psychology of Conflict: Mediating in a Diverse World" is being launched on Saturday at an international peace summit on mediation in London, organized by Regent's University London and the Tutu Foundation UK.