【意识的定义】意识可以定义为“个体觉察事物（包括自我）存在的脑功能状态.”也就是说，意识是脑对“存在”的觉察．感知“存在”就是对自我和事物的觉察，发生在清醒状态下．对“存在”的觉察是脑的基本功能，也是注意、学习、认知、思维等功能的前提．

国际上许多实验室，研究麻醉导致的意识丧失以及麻醉后意识的重启动，来揭示意识的神经基础．最近，Solovey等(J Neurosci, 2015, 35(30):10866)发现，不同麻醉药物诱导的脑活动模式不同．如果忽略那些具体活动的特征，意识丧失与皮层动力学稳态之间，确实存在普遍的相关性．以此类比，意识的丧失如同踩下钢琴上的减震器踏板，使琴声消散得更快，而不顾及特定旋律的演奏.

如果能够在基础代谢的状态下，即个体刚刚从睡梦中苏醒，觉察到自我和环境存在的时刻研究意识，就可能避免各种麻醉药物对脑活动的干扰．

【Definition】 Consciousness can be described as “a brain basic function that an individual perceives oneself existing in a real world (environment).“ This is to say, consciousness works for a human to realize the existence of anything including himself or herself under wakefulness. The perception of the existence is a brain fundamental function for attention, learning, cognition and thinking, etc., because these activities are performed under consciousness.

So far, many scientific laboratories study human consciousness related with anesthesia because they attempt to reveal how consciousness works when brain reboots awareness. Recently, Solovey and colleagues (J Neurosci, 2015, 35(30): 10866) found that different anesthetics induce different patterns of brain activity. Loss of consciousness is universally and reliably associated with stabilization of cortical dynamics regardless of the specific activity characteristics. To give an analogy, their analyses suggest that loss of consciousness is akin to depressing the damper pedal on the piano which makes the sounds dissipate quicker regardless of the specific melody being played.

Here is a suggestion that the consciousness under the basic metabolism should be observed when a person just awake from asleep state, because s/he just realizes herself or himself existing in a real world, without disturbance from those of drugs for anesthesia of brain.