Understanding neuroimaging.

Neuroimaging is an emergent method of investigation for studying the human brain in healthy and impaired populations. An increasing number of these investigations involve topics important to rehabilitation. Thus, a basic understanding of the more commonly used neuroimaging techniques is important for understanding and interpreting this growing area of research. Included in this article is a description of the signal source, the advantages and limitations of each technique, considerations for study design, and how to interpret cortical imaging data. Particular emphasis is placed on functional magnetic resonance imaging because of its ubiquitous presence in rehabilitation research.