William James’s use of “time in passing” and “stream of thoughts” may be two sides of the same coin that emerge from the brain segmenting the continuous flow of information into discrete events. Herein, we investigated how the density of events affects two temporal experiences: the felt duration and speed of time. Using a temporal bisection task, participants classified seconds-long videos of naturalistic scenes as short or long (duration), or slow or fast (passage of time). Videos contained a varying number and type of events. We found that a large number of events lengthened subjective duration and accelerated the felt passage of time. Surprisingly, participants were also faster at estimating their felt passage of time compared to duration. The perception of duration scaled with duration and event density, whereas the felt passage of time scaled with the rate of change. Altogether, our results suggest that distinct mechanisms underlie these two experiential times.

威廉·詹姆斯对“流逝的时间”和“思想流”的使用可能是同一枚硬币的两面，它们从大脑中出现，将连续的信息流分割成离散的事件。在这里，我们研究了事件的密度如何影响两种时间体验：感知的持续时间和时间的速度。使用时间二分任务，参与者将自然场景的几秒长视频分类为短或长（持续时间），或慢或快（时间流逝）。视频包含不同数量和类型的事件。我们发现大量事件会延长主观持续时间并加速感觉时间的流逝。令人惊讶的是，与持续时间相比，参与者也能更快地估计他们感受到的时间流逝。对持续时间的感知随着持续时间和事件密度而变化，而感受到的时间流逝则随着变化率而变化。总而言之，我们的结果表明，这两个经历时期背后存在着不同的机制。