age-matched right-handed healthy volunteers

Patients present reproducible signs of awareness such as purposeful eye movements or response to verbal order

Patients preserved autonomous functioning (e.g., preserved sleep-wake cycles),but without awareness of oneself or of the environment

Neutral voice is a meaningless sound (namely the interjection "ah") and the emotional stimuli were the same voice pronouncing the same word with an emotional prosody of happiness or sadness.The stimulus material consisted of positive and negative sound selected from the International Affective Digitalized Sounds (IADS) database.In order to identify experimental stimuli sets that were matched for ratings of arousal and valence between the two valence types,investigators used an algorithm to equate normative valence and arousal ratings for the selection of auditory stimuli.

The event-related potential waveforms uncover voluntary responses to external stimuli that could assist in detecting signs of consciousness to reduce the risk of misdiagnosis. P300 is a large positive going potential that increases in amplitude from the frontal to parietal electrodes and has a peak latency of about 300 ms for auditory and 400 ms for visual stimuli. And N1 is a negative potential in the posterior superior temporal lobe with the peak latency of about 170ms.Peak amplitudes and latency were obtained for the interest ERP components(N1,P300) .Peak amplitudes and latency for were analysed in a series of repeated-measures ANOVAs for each component (N1, P2), with factors of condition (emotion: mean happy/angry vs. neutral).

CRS-R has been designed to differentiate VS from MCS and consists of 23 hierarchically arranged items that comprise six subscales addressing arousal, auditory, visual, motor, oromotor/verbal, and communication functions. The lowest item on each subscale represents reflexive activity while the highest item represents cognitively mediated behaviors.