Verleger Rolf, Siller Bastian, Ouyang Guang, Śmigasiewicz Kamila
Department of Neurology, University of Lübeck, Germany; Institute of Psychology II, University of Lübeck, Germany.
Department of Neurology, University of Lübeck, Germany.
Biol Psychol. 2017 May;126:1-11. doi: 10.1016/j.biopsycho.2017.03.011. Epub 2017 Mar 31.
When key-press responses to targets have to be withheld until the presentation of response prompts, target-evoked P3 amplitudes are reduced and so is the P3 difference between rare and frequent targets (the oddball effect on P3). Recently we showed that this even applied when go-signals followed targets by 100ms. Here we aimed at replicating this result with more fine-grained temporal resolution in 100ms steps from 0ms to 500ms, and dissecting the P3 complex to stimulus- and response-related portions by applying residue iteration decomposition (RIDE). Frequent and rare target stimuli (in random series) were followed by go signals (and occasional no-go signals), with block-wise fixed stimulus-onset asynchronies (SOAs) from 0ms to 500ms. Target-evoked P3 amplitudes decreased monotonically across SOAs. Part of this decrease might have been due to an overlapping Contingent Negative Variation (CNV) prior to go signals, increasing across SOAs. When CNV was subtracted out by forming rare-frequent difference waveforms, oddball-P3 was largest at SOA 0, smallest at SOA 500, and equally large at SOAs 100-400. According to RIDE, it was P3's response-related part that was increased at SOA0. These results may be interpreted in terms of the stimulus-response-link reactivation hypothesis of P3.
当对目标的按键反应必须延迟到呈现反应提示时，目标诱发的P3波幅会降低，罕见目标与频繁目标之间的P3差异（P3的奇偶数效应）也会降低。最近我们发现，即使启动信号在目标之后100毫秒出现，这种情况仍然适用。在这里，我们旨在以更精细的时间分辨率（从0毫秒到500毫秒，以100毫秒为步长）重复这一结果，并通过应用残差迭代分解（RIDE）将P3复合体分解为与刺激和反应相关的部分。频繁和罕见的目标刺激（以随机序列呈现）之后是启动信号（以及偶尔的停止信号），块内固定刺激起始异步（SOA）从0毫秒到500毫秒。目标诱发的P3波幅在SOA范围内单调下降。这种下降的部分原因可能是启动信号之前存在重叠的关联性负变（CNV），且其在SOA范围内增加。当通过形成罕见 - 频繁差异波形减去CNV时，奇偶数P3在SOA 0时最大，在SOA 500时最小，在SOA 100 - 400时相等。根据RIDE分析，在SOA0时增加的是P3与反应相关的部分。这些结果可以根据P3的刺激 - 反应链接重新激活假说进行解释。
