as dopamine and serotonin Named after it's discoverer, Alois Alzheimer, Alzheimer's Disease is the most common subtype of neurocognitive disorder, accounting for about 75% of all patients. It has a slow and progressive course of cognitive decline. The first noticeable signs include forgetting recent events or names, repeating statements or questions, getting lost while driving in familiar places, and experiencing difficulty with calculations. Many of such patients are able to maintain a positive quality of life for some years after diagnosis. This disease results in more severe impairments in the ability to use language, make decisions, and engage in self-care. Behavioral problems also occur and include disrupted sleep, wandering, irritability, and aggression. The rate of progressive deterioration in cognitive capabilities and functioning increases as the severity of the disease worsens. Diagnosed when a patient's history, laboratory tests, and/or brain imaging studies indicate cognitive impairment as a result of cardiovascular disease such as stroke, transient ischemic attack, coronary artery disease, or untreated high blood pressure. In these conditions, blockages of blood vessels result in tissue death (infarction) in the brain. Damage may be to a single major vessel or lots of smaller ones. Vascular neurocognitive disorder has different clinical features than Alzhiemer's. Substance use, particularly alcohol-related disorder, can lead to dementia that is difficult to differentiate from Alzheimer's. Substance use may also increase vulnerability to other forms of dementia and for other contributing factors such as head trauma, infectious disease, and vitamin deficiency. Major and mild neurocognitive disorder occurs in five to ten percent of adults age 65 and over. Alzheimer's disease is the most common type, diagnosed in up to 75% of cases. Unfortunately, many patients with neurocognitive disorders remain undiagnosed and untreated. The impact of neurocognitive disorders on patients, their families, and the health care system is enormous. As cognitive abilities and functional capacity deteriorate, negative emotional, social, and behavioral outcomes occur. In the early stages, social and emotional withdrawal is common. Many Alzheimer's disease patients demonstrate anxiety and depression as well, which result in more behavioral problems and increased limitations in daily activities. By 2030, the percentage of people with neurocognitive disorders in the United States is expected to reach 65 million, with associated increases in health care costs. Neurocognitive disorder also affects family caregivers, who are at increased risk themselves for depression and anxiety. Until recently, our thinking has been dominated by the ideas of mind-body dualism. According to this view, mind and body function independently, although they may interact. This philosophy persisted for many centuries with significant efforts to identify biological causes for medical illness and a relative neglect of attention to psychological variables influencing physical health. Only recently psychology has begun to have a role in identifying and treating medical illness. At present, psychologists play important roles in prevention, treatment, or management of physical health problems. Gradually, psychologists found certain personality patterns related to specific medical illnesses. Now, the bio-psycho-social model of physical illness recognizes the contributions of body, mind, and the social environment to the development of illness Any negative emotional experience that is accompanied by biochemical, physiological, cognitive, and behavioral responses that attempt to change or adjust to the stressor. A stressor is any agent that produces tension or another negative emotion such as fear and prepares the organism for a fight-or-flight response. Stressors can be physical (such as a medical disease or physical injury), environmental (natural disaster, change in living situation), interpersonal-social (breakup of a relationship, argument with a family member), or 