Imaging is becoming an increasingly important tool in both research and clinical care. A range of imaging technologies now provide unprecedented sensitivity to visualization of brain structure and function from the level of individual molecules to the whole brain. Many imaging methods are noninvasive and allow dynamic processes to be monitored over time. Imaging is enabling researchers to identify neural networks involved in cognitive processes; understand disease pathways; recognize and diagnose diseases early, when they are most effectively treated; and determine how therapies work.
Moreover, as in other areas of biomedical research, these opportunities are interactive. As an example, imaging can provide a better understanding about a disease process that leads to discovery of potential therapies that intervene in that process. Thereafter, imaging can help provide a better understanding about how that drug or therapy works at the molecular level, leading to a more precise understanding of the disease process and then to development of a more highly specific drug to treat it.
Different types of imaging are used to reveal brain structure (anatomy), physiology (functions), and biochemical actions of individual cells and of the molecules that compose them, and of cells’ functions, behaviors and interactions. The three main categories, therefore, are often referred to as structural, functional and molecular imaging. While many imaging techniques are used throughout the body, the descriptions provided here focus on their use in the nervous system, primarily the brain.
Alone and in combination, these imaging techniques are transforming our understanding of how the brain functions, how immune cells function, and how immune cells interact with the brain in health and disease.