University of California, Davis.
University of Miami.
J Cogn Neurosci. 2019 Aug;31(8):1184-1204. doi: 10.1162/jocn_a_01419. Epub 2019 May 6.
The ability to discriminate among goal-relevant stimuli tends to diminish when detections must be made continuously over time. Previously, we reported that intensive training in (focused-attention) meditation can improve perceptual discrimination of difficult-to-detect visual stimuli [MacLean, K. A., Ferrer, E., Aichele, S. R., Bridwell, D. A., Zanesco, A. P., Jacobs, T. L., et al. Intensive meditation training improves perceptual discrimination and sustained attention. , , 829-839, 2010]. Here we extend these findings to examine how discrimination difficulty and meditation training interact to modulate event-related potentials of attention and perceptual processing during vigilance. Training and wait-list participants completed a continuous performance task at the beginning, middle, and end of two 3-month meditation interventions. In the first intervention (Retreat 1), the continuous performance task target was adjusted across assessments to match training-related changes in participants' perceptual capacity. In the second intervention (Retreat 2), the target was held constant across training, irrespective of changes in discrimination capacity. No training effects were observed in Retreat 1, whereas Retreat 2 was associated with changes in the onset of early sensory signals and an attenuation of within-task decrements at early latencies. In addition, changes at later stimulus processing stages were directly correlated with improvements in perceptual threshold across the second intervention. Overall, these findings demonstrate that improvements in perceptual discrimination can modulate electrophysiological markers of perceptual processing and attentional control during sustained attention, but likely only under conditions where an individual's discrimination capacity is allowed to exceed the demand imposed by the difficulty of a visual target. These results contribute to basic understanding of the dependence of perceptual processing and attentional control to contextual demands and their susceptibility to directed mental training.
当必须随着时间的推移持续进行检测时，对目标相关刺激进行区分的能力往往会下降。之前，我们报告说，（集中注意力）冥想的强化训练可以提高对难以察觉的视觉刺激的知觉辨别能力[MacLean，K. A.，Ferrer，E.，Aichele，S. R.，Bridwell，D. A.，Zanesco，A. P.，Jacobs，T. L.，等人。强化冥想训练可提高知觉辨别力和持续性注意力。，2010 年，829-839]。在这里，我们扩展了这些发现，以研究辨别难度和冥想训练如何相互作用，从而调节警觉期间注意和知觉处理的事件相关电位。训练组和候补组在两个为期 3 个月的冥想干预的开始、中间和结束时都完成了连续表现任务。在第一次干预（静修 1）中，随着参与者知觉能力的变化，连续表现任务的目标在评估中进行了调整。在第二次干预（静修 2）中，目标在训练过程中保持不变，无论辨别能力的变化如何。在静修 1 中没有观察到训练效果，而静修 2与早期感觉信号的起始变化以及早期潜伏期内任务内衰退的减弱有关。此外，后期刺激处理阶段的变化与第二次干预过程中感知阈值的提高直接相关。总的来说，这些发现表明，知觉辨别力的提高可以调节持续注意期间知觉加工和注意力控制的电生理标记，但可能仅在个体的辨别能力允许超过视觉目标难度所施加的要求的情况下。这些结果有助于理解知觉处理和注意力控制对上下文需求的依赖性及其对定向心理训练的敏感性。
