Muller-Gass Alexandra, Campbell Kenneth
School of Psychology, University of Ottawa, Ottawa, Canada K1N 6N5.
Int J Psychophysiol. 2002 Dec;46(3):177-95. doi: 10.1016/s0167-8760(02)00111-3.
This article reviews the effects of selective attention on event-related potentials (ERPs). Attention has little, if any, effect on short-latency exogenous ERPs. The longer-latency ERPs can be markedly affected by manipulation of the subject's level of attention. For example, a late positive wave, P300, appears to occur only if subjects actively detect an infrequently occurring target stimulus. However, a number of other late positive waves may also occur independently of the direction of attention, particularly if elicited by highly biologically or psychologically relevant stimuli. Attention may also interact with an earlier, apparently exogenous, negative waveform, N1. This could be due to the overlapping and summating effect of an attentional-related waveform, the processing negativity. The presentation of a physically deviant stimulus occurring among a train of homogeneous standard stimuli will elicit another negative wave, the mismatch negativity (MMN). The MMN has traditionally been thought to occur independently of attention. More recent studies have, however, shown that attention can modulate the MMN. This may, however, be explained by the summating effects of other overlapping components. Interpreting the scalp-recorded ERP can therefore require judicious care. Design of experiments must take into account the fact that the magnitude of attentional effects will depend on a number of different influences, some of which are very subtle and complex. A problem with any study in the waking and alert human is that the subject may not be able to completely ignore stimuli, in spite of instructions to do so. For this reason, the study of unconscious states, such as sleep, may prove to be especially fruitful in understanding the effects of attention in the waking state.
本文综述了选择性注意对事件相关电位（ERP）的影响。注意对短潜伏期外源性ERP几乎没有影响（如果有影响的话也很小）。较长潜伏期的ERP会受到受试者注意水平操控的显著影响。例如，一个晚期正波，P300，似乎只有在受试者积极检测到一个不常出现的目标刺激时才会出现。然而，许多其他晚期正波也可能独立于注意方向出现，特别是如果由高度生物学或心理学相关的刺激引发。注意也可能与一个较早的、明显是外源性的负向波形N1相互作用。这可能是由于一个与注意相关的波形，即加工负波的重叠和叠加效应。在一系列均匀的标准刺激中出现的物理偏差刺激会引发另一个负波，即失配负波（MMN）。传统上认为MMN的出现与注意无关。然而，最近的研究表明注意可以调节MMN。不过，这可能是由其他重叠成分的叠加效应来解释的。因此，解读头皮记录的ERP需要谨慎小心。实验设计必须考虑到注意效应的大小将取决于许多不同的影响因素，其中一些非常微妙和复杂。在清醒且警觉的人类身上进行的任何研究都存在一个问题，即尽管有指示，但受试者可能无法完全忽略刺激。出于这个原因，对无意识状态（如睡眠）的研究可能在理解清醒状态下的注意效应方面特别有成效。
