Neuropsychologists investigate the connection between human behaviour and the brain. They diagnose and treat a wide range of central nervous system disorders caused by disease, injury, or age-related brain changes. They also work with youngsters who have learning impairments. Neuropsychologists may assess a patient's IQ, focus, or memory, as well as conduct interviews to learn about their medical history. They prepare extensive reports that incorporate their patient notes and test results, and then collaborate with doctors and other healthcare professionals to develop a strategy for the patient's success. Students, interns, and other hospital personnel are also taught and supervised by neuropsychologists. They do research and design rehabilitation programmes for patients who are recovering from or adapting to cognitive impairment. Clinical neuropsychologists treat patients with neurological diseases or brain injuries with psychotherapy, behaviour therapy, and other counselling services. They diagnose and treat diseases such as drug dependency, dementia, and toxic exposure. Neuropsychologists operate in laboratories, colleges and universities, and rehabilitation facilities. The majority of roles require a Ph.D. in neuropsychology or a similar subject. Some positions necessitate licensure and certification.