Wutz Andreas, Shukla Anuj, Bapi Raju S, Melcher David
Center for Mind & Brain Sciences, University of Trento, Rovereto, Italy.
Cognitive Science Laboratory, International Institute of Information Technology, Hyderabad, India.
PLoS One. 2015 Aug 26;10(8):e0135794. doi: 10.1371/journal.pone.0135794. eCollection 2015.
Perception of temporal duration is subjective and is influenced by factors such as attention and context. For example, unexpected or emotional events are often experienced as if time subjectively expands, suggesting that the amount of information processed in a unit of time can be increased. Time dilation effects have been measured with an oddball paradigm in which an infrequent stimulus is perceived to last longer than standard stimuli in the rest of the sequence. Likewise, time compression for the oddball occurs when the duration of the standard items is relatively brief. Here, we investigated whether the amount of information processing changes when time is perceived as distorted. On each trial, an oddball stimulus of varying numerosity (1-14 items) and duration was presented along with standard items that were either short (70 ms) or long (1050 ms). Observers were instructed to count the number of dots within the oddball stimulus and to judge its relative duration with respect to the standards on that trial. Consistent with previous results, oddballs were reliably perceived as temporally distorted: expanded for longer standard stimuli blocks and compressed for shorter standards. The occurrence of these distortions of time perception correlated with perceptual processing; i.e. enumeration accuracy increased when time was perceived as expanded and decreased with temporal compression. These results suggest that subjective time distortions are not epiphenomenal, but reflect real changes in sensory processing. Such short-term plasticity in information processing rate could be evolutionarily advantageous in optimizing perception and action during critical moments.
对时间持续时长的感知是主观的，并且会受到注意力和情境等因素的影响。例如，意外或情绪化的事件常常让人感觉时间在主观上延长了，这表明单位时间内处理的信息量可能会增加。时间膨胀效应已通过奇偶数范式进行测量，在该范式中，一个不常见的刺激被感知为比序列中其他标准刺激持续的时间更长。同样，当标准刺激的持续时间相对较短时，对奇偶数刺激会出现时间压缩现象。在此，我们研究了当时间被感知为扭曲时，信息处理量是否会发生变化。在每次试验中，呈现一个数量（1 - 14个项目）和持续时间各不相同的奇偶数刺激，同时伴有短（70毫秒）或长（1050毫秒）的标准刺激。观察者被要求数出奇偶数刺激中的点数，并判断其相对于该试验中标准刺激的相对持续时间。与先前的结果一致，奇偶数刺激被可靠地感知为时间扭曲：对于较长的标准刺激块会被感知为延长，对于较短的标准刺激则会被感知为压缩。这些时间感知扭曲的出现与感知处理相关；也就是说，当时间被感知为延长时，计数准确性会提高，而随着时间压缩则会降低。这些结果表明，主观时间扭曲并非附带现象，而是反映了感觉处理中的实际变化。这种信息处理速率的短期可塑性在关键时刻优化感知和行动方面可能具有进化优势。
