Anxiety is a universal human emotion that has been described as the price-tag on freedom. It is the price we pay for a brain that can anticipate the future. But when anxiety spirals out of control it can take over our lives as we battle against phobias, panic attacks, dread and debilitating fear. So how is anxiety triggered and constructed in the brain? Is the almond-shaped amygdala the seat of fear or are our anxieties constructed in other parts of the brain? And for those made miserable by anxiety, how best can it be treated? Bridget Kendall explores the biology of anxiety and some unexpected approaches to treatment, including friendship benches and therapy horses. She is joined by Joseph LeDoux, author of Anxiety and professor of Neuroscience and director of the Emotional Brain Institute, New York University; Dr Dixon Chibanda, a consultant Psychiatrist in Zimbabwe and pioneer of the Friendship Bench; Susanna Forrest, a British authority on the horse and author of The Age of Horse: An Equine Journey through Human History. (Photo: A young man holding his head in his hands)