Doricchi Fabrizio, Pellegrino Michele, Marson Fabio, Pinto Mario, Caratelli Ludovica, Cestari Vincenzo, Rossi-Arnaud Clelia, Lasaponara Stefano
Università degli Studi di Roma "La Sapienza".
Fondazione Santa Lucia IRCCS, Rome, Italy.
J Cogn Neurosci. 2020 Jun;32(6):1046-1060. doi: 10.1162/jocn_a_01534. Epub 2020 Jan 22.
Orienting of attention produces a "sensory gain" in the processing of visual targets at attended locations and an increase in the amplitude of target-related P1 and N1 ERPs. P1 marks gain reduction at unattended locations; N1 marks gain enhancement at attended ones. Lateral targets that are preceded by valid cues also evoke a larger P1 over the hemisphere contralateral to the no-target side, which reflects inhibition of this side of space [Slagter, H. A., Prinssen, S., Reteig, L. C., & Mazaheri, A. Facilitation and inhibition in attention: Functional dissociation of pre-stimulus alpha activity, P1, and N1 components. , , 25-35, 2016]. To clarify the relationships among cue predictiveness, sensory gain, and the inhibitory P1 response, we compared cue- and target-related ERPs among valid, neutral, and invalid trials with predictive (80% valid/20% invalid) or nonpredictive (50% valid/50% invalid) directional cues. Preparatory facilitation over the visual cortex contralateral to the cued side of space (lateral directing attention positivity component) was reduced during nonpredictive cueing. With predictive cues, the target-related inhibitory P1 was larger over the hemisphere contralateral to the no-target side not only in response to valid but also in response to neutral and invalid targets: This result highlights a default inhibitory hemispheric asymmetry that is independent from cued orienting of attention. With nonpredictive cues, valid targets reduced the amplitude of the inhibitory P1 over the hemisphere contralateral to the no-target side whereas invalid targets enhanced the amplitude of the same inhibitory component. Enhanced inhibition was matched with speeded reorienting to invalid targets and drop in attentional costs. These findings show that reorienting of attention is modulated by the combination of cue-related facilitatory and target-related inhibitory activity.
注意力的定向在对被关注位置的视觉目标进行加工时会产生一种“感觉增益”，并使与目标相关的P1和N1事件相关电位（ERP）的波幅增加。P1标志着未被关注位置的增益降低；N1标志着被关注位置的增益增强。在无目标侧对侧半球上，由有效线索引导的横向目标也会诱发更大的P1，这反映了对该侧空间的抑制作用[斯拉赫特，H.A.，普林森，S.，雷特格，L.C.，&马扎赫里，A.注意力中的促进和抑制：刺激前α活动、P1和N1成分的功能分离。，，25 - 35，2016]。为了阐明线索可预测性、感觉增益和抑制性P1反应之间的关系，我们比较了在具有预测性（80%有效/20%无效）或非预测性（50%有效/50%无效）方向线索的有效、中性和无效试验中与线索和目标相关的ERP。在非预测性线索提示期间，与空间线索提示侧对侧的视觉皮层上的准备性促进作用（侧方引导注意力正性成分）降低。对于预测性线索，不仅对有效目标，而且对中性和无效目标，在无目标侧对侧半球上与目标相关的抑制性P1都更大：这一结果突出了一种默认的抑制性半球不对称性，它独立于线索引导的注意力定向。对于非预测性线索，有效目标降低了无目标侧对侧半球上抑制性P1的波幅，而无效目标则增强了同一抑制性成分的波幅。增强的抑制作用与对无效目标的快速重新定向以及注意力成本的降低相匹配。这些发现表明，注意力的重新定向受到线索相关促进活动和目标相关抑制活动组合的调节。
