The neural time factor in conscious and unconscious events.
The neural time factor in conscious and unconscious events.
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DOI：
10.1002/9780470514412.ch7
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发表时间：
2007-09
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影响因子：
--
通讯作者：
B. Libet
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文献类型：
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作者：
B. Libet
我们早期的证据表明，产生有意识的感觉体验需要相当长的适当的大脑活动时间（最长约0.5秒）;这意味着感觉世界的体验相对于真实的时间是延迟的。经验的主观时间可以追溯到最早的信号到达皮层的时间。我们的“持续时间”理论指出，从无意识到有意识的心理功能的转变至少部分取决于适当神经活动持续时间的增加。我们的实验发现，有意识的行动意图出现后，只有约350毫秒的延迟后，从特定的大脑活动，在自愿行为之前的开始提供了间接的证据。在一个直接的实验测试中，一个信号（对躯体感觉丘脑的刺激）在强迫选择测试中被正确地检测到，即使刺激持续时间太短而不能产生对信号的任何意识;从没有意识的正确检测到有意识的检测需要额外的400毫秒重复相同的神经齐射上升到感觉皮层。“时间开启”理论对各种无意识-有意识的互动有重要意义。
Our earlier evidence had indicated that a substantial duration of appropriate cerebral activity (up to about 0.5 s) is required for the production of a conscious sensory experience; this means the sensory world is experienced delayed with respect to real time. Subjective timing of the experience can be retroactively referred to the time of the earliest signal arriving at the cortex. Our 'time-on' theory states that the transition from an unconscious to a conscious mental function is determined, at least in part, by an increase in the duration of appropriate neural activities. Our experimental finding that conscious intention to act appears only after a delay of about 350 ms from the onset of specific cerebral activity that precedes a voluntary act provided indirect evidence for the theory. In a direct experimental test a signal (stimulus to somatosensory thalamus) was correctly detected in a forced-choice test even when the stimulus duration was too short to produce any awareness of the signal; to go from correct detection with no awareness to detection with awareness required an additional 400 ms of the repetitive identical neural volleys ascending to sensory cortex. 'Time-on' theory has important implications for a variety of unconscious-conscious interactions.