A book that will teach you to understand mental problems and introduce you to the basic cognitive functions of the brain. Yao Nailin considers a wide range of topics - from difficulties in communication to bipolar disorder. Lack of concentration, anxiety, depression, insomnia - these mental demons can haunt us everywhere. But how do you know which demon you're dealing with? How to cope with the onslaught of a rapidly changing life and the psychological difficulties of growing up? How to keep your mental health in the modern world? The answers to these questions are hidden in the book by Yao Nailin, a postdoctoral researcher in psychiatry at Yale University and a doctor of psychiatry at the University of Hong Kong. You will learn how to diagnose symptoms of anxiety, depression, obsessive-compulsive disorder and other common psychological problems. You will understand what the basics of the brain's cognitive functions are, including concentration, memory and creativity, and how to help them recover. Read about how to overcome stress and emotional challenges. The book will become your guide in the world of psychological health. In it, you will find tools that will help you defeat mental demons and regain control of your life.