Graziano Martin, Sigman Mariano
Physics Department, Integrative Neuroscience Laboratory, Universidad de Buenos Aires, Buenos Aires, Argentina.
PLoS One. 2009;4(3):e4909. doi: 10.1371/journal.pone.0004909. Epub 2009 Mar 17.
Human subjects can report many items of a cluttered field a few hundred milliseconds after stimulus presentation. This memory decays rapidly and after a second only 3 or 4 items can be stored in working memory. Here we compared the dynamics of objective performance with a measure of subjective report and we observed that 1) Objective performance beyond explicit subjective reports (blindsight) was significantly more pronounced within a short temporal interval and within specific locations of the visual field which were robust across sessions 2) High confidence errors (false beliefs) were largely confined to a small spatial window neighboring the cue. The size of this window did not change in time 3) Subjective confidence showed a moderate but consistent decrease with time, independent of all other experimental factors. Our study allowed us to asses quantitatively the temporal and spatial access to an objective response and to subjective reports.
人类受试者在刺激呈现后几百毫秒内就能报告杂乱视野中的许多项目。这种记忆迅速衰退,一秒钟后工作记忆中只能存储3到4个项目。在这里,我们将客观表现的动态与主观报告的一种测量方法进行了比较,我们观察到:1)超出明确主观报告(盲视)的客观表现,在短时间间隔内以及视野的特定位置上显著更明显,并且在各次实验中都很稳定;2)高置信度错误(错误信念)主要局限于与线索相邻的一个小空间窗口内。这个窗口的大小不会随时间变化;3)主观置信度随时间呈现适度但一致的下降,与所有其他实验因素无关。我们的研究使我们能够定量评估对客观反应和主观报告的时间和空间获取情况。