Abstract

Rapid technological advances have produced a variety of novel techniques that allow a comprehensive assessment of brain function to be combined with detailed information about brain structure and connectivity. Any assessment that is based on exhibited behavior after brain injury will be prone to error for a number of reasons. These questions are explored in the context of recent studies in both healthy populations and brain injured patients that have sought to investigate covert awareness through the use of functional neuroimaging. Those circumstances in which functional magnetic resonance imaging data can be used to infer awareness in the absence of a behavioral response are contrasted with those circumstances in which it cannot. This distinction is fundamental for understanding and interpreting patterns of brain activity following acute brain injury and has implications for clinical care, diagnosis, prognosis, and medicolegal decision-making after serious brain injury.