The roots of modern psychological torture can be traced back to the early 20th century, when psychologists began to explore the use of psychological techniques to influence human behavior. These early pioneers in the field of psychological torture believed that by understanding the psychological vulnerabilities of an individual, they could manipulate their thoughts, feelings, and actions without resorting to physical violence. As a result, a number of psychological techniques were developed that were designed to induce pain, fear, and anxiety in the target individual, including sleep deprivation, sensory deprivation, and social isolation. These techniques were initially used in military and intelligence settings, but they eventually spread to other areas, such as law enforcement and corrections. Today, psychological torture is a common tool of oppression and control in many parts of the world.