Magnetic resonance spectroscopy of the brain: a review of physical principles and technical methods.

Magnetic resonance spectroscopy (MRS) provides unique information about the neurobiological substrates of brain function in health and disease. However, many of the physical principles underlying MRS are distinct from those underlying magnetic resonance imaging, and they may not be widely understood by neuroscientists new to this methodology. This review describes these physical principles and many of the technical methods in current use for MRS experiments. A better understanding these principles and methods may help investigators select pulse sequences and quantification methods best suited to the aims of their research program and avoid pitfalls that can hamper new investigators in this field.