Behavioral responsiveness in patients with disorders of consciousness

Until now, the main way to assess whether a patient is conscious or not is to observe what he can do spontaneously or in response to stimulation. Although there is a growing body of research on the subject, detecting oriented/voluntary responses is still extremely challenging. Motor, verbal, and cognitive impairments; fl uctuations of vigilance; and medications with impact on the central nervous system are among the factors complicating the diagnosis. Establishing a proper diagnosis is nevertheless of high clinical relevance when considering patients’ prognosis and treatment. In this review, we will characterize the behavioral patterns of the various levels of consciousness, we will explain how challenging it is to detect signs of consciousness, and which tools currently exist to help in the assessment of those signs. Secondarily, we will present preliminary data investigating the interest of various sensory modalities in determining the diagnosis of patients with severe brain injury. © Springer International Publishing Switzerland 2016.