Petro Nathan M, Keil Andreas
Center for the Study of Emotion and Attention, University of Florida, PO Box 112766, Gainesville, FL, 32611, USA.
Department of Psychology, University of Florida, PO Box 112766, Gainesville, FL, 32611, USA.
Exp Brain Res. 2015 Dec;233(12):3583-95. doi: 10.1007/s00221-015-4418-2. Epub 2015 Sep 4.
Reporting the second of two targets within a stream of distracting words during rapid serial visual presentation (RSVP) is impaired when the targets are separated by a single distractor word, a deficit in temporal attention that has been referred to as the attentional blink (AB). Recent conceptual and empirical work has pointed to pre-target brain states as potential mediators of the AB effect. The current study examined differences in pre-target electrophysiology between correctly and incorrectly reported trials, considering amplitude and phase measures of alpha oscillations as well as the steady-state visual evoked potential (ssVEP) evoked by the RSVP stream. For incorrectly reported trials, relatively lower alpha-band power and greater ssVEP inter-trial phase locking were observed during extended time periods preceding presentation of the first target. These results suggest that facilitated processing of the pre-target distracter stream indexed by reduced alpha and heightened phase locking characterizes a dynamic brain state that predicts lower accuracy in terms of reporting the second target under strict temporal constraints. Findings align with hypotheses in which the AB effect is attributed to neurocognitive factors such as fluctuations in pre-target attention or to cognitive strategies applied at the trial level.
在快速序列视觉呈现(RSVP)过程中,当两个目标被一个干扰词隔开时,报告第二个目标的能力会受到损害,这种时间注意力缺陷被称为注意瞬脱(AB)。最近的概念和实证研究指出,目标前脑状态可能是AB效应的调节因素。本研究考察了正确和错误报告试验之间目标前电生理的差异,考虑了阿尔法振荡的幅度和相位测量以及RSVP流诱发的稳态视觉诱发电位(ssVEP)。对于错误报告的试验,在第一个目标呈现前的较长时间段内,观察到相对较低的阿尔法波段功率和较大的ssVEP试验间相位锁定。这些结果表明,以阿尔法降低和相位锁定增强为指标的目标前干扰流的易化处理,表征了一种动态脑状态,该状态预示着在严格的时间限制下报告第二个目标时准确性较低。研究结果与一些假设相符,这些假设认为AB效应归因于神经认知因素,如目标前注意力的波动或试验水平上应用的认知策略。