In recent years, promoting wakening attempts in patients with disorders of consciousness are increasing, but there are a lack of objective indicators to evaluate the efficacy and further researches on the brain mechanism during the wakening processing. So, the study first assessed the cerebral response during emotional acoustic stimuli with quantitative EEG and ERP(Event-related potential), and next, the investigators explored the relationship between brain activation and patients' recovery.

Auditory stimuli have potential beneficial effects on cognitive functions and consciousness in patients with disorders of consciousness (DOC)，especially the emotional sound; however, precise and accurate quantitative indices to estimate cerebral activation to different auditory stimuli remain scarce. In this study, investigators assessed the response of different brain regions to three acoustic stimuli using quantitative electroencephalography (QEEG) and ERP(Event-related potential),and further investigated the predictive value of QEEG in the prognosis of DOC.

Brain-damaged patients :

Inclusion Criteria:

1. Disorders of consciousness (Traumatic brain injury, stroke or anoxic encephalopathy)
2. Coma diagnosis (Plum and Posner, 1966), vegetative state (Task Force, 1994) or minimally conscious state (Giacino, Ashwal et al. 2002)
3. Lack of autonomic crisis since one week minimum
4. Medical condition considered stable
5. Patients who do not present hearing loss. Peaks I and II of Brainstem Auditory Evoked Potentials (BAEP) will be normal.

Exclusion Criteria:

1. hearing Problem
2. Uncontrolled Epilepsy
3. Autonomic crises
4. Medical unstable state
5. Pregnant or likely to be (interrogation data) or breastfeeding woman

Healthy participants :

Inclusion Criteria:

1. Subjects with normal hearing
2. Absence of neurological disorder
3. Subjects able to understand the experimental instructions

Exclusion Criteria:

1. Hearing problems and / or hearing loss higher than 30 decibels Hearing Level (dB HL) at a frequency band from 250 to 8000 Hz
2. Neurological disorders
3. Pregnant or likely to be (interrogation data) or breastfeeding woman