A neuropsychologist is a healthcare professional who specializes in understanding how the brain and nervous system work, particularly as they relate to behavior, cognition, and emotion. They use various assessment tools and techniques to evaluate patients with neurological or psychiatric conditions that may affect their thinking, memory, or emotional regulation. Neuropsychologists often work in hospitals, rehabilitation centers, or private practice settings, providing diagnostic services, treatment planning, and counseling for individuals experiencing cognitive or behavioral difficulties due to brain injury or illness.