Pang Cheuk Yee, Mueller Matthias M
Institute of Psychology, University of Leipzig, 04109 Leipzig, Germany.
Institute of Psychology, University of Leipzig, 04109 Leipzig, Germany.
Biol Psychol. 2015 Sep;110:91-9. doi: 10.1016/j.biopsycho.2015.07.002. Epub 2015 Jul 18.
We investigated competitive neural interactions for processing resources during sustained spatial attention in somatosensation. Participants received concurrent vibrotactile stimulation at different frequencies to either non-adjacent left hand fingers (within-hand) or fingers on two hands (between-hands) for 4500 ms to elicit steady-state somatosensory evoked potentials (SSSEPs). They attended to either one or both stimulated locations, respectively, and responded to rare events embedded in the ongoing stream. Behavioral and electrophysiological results revealed competitive interaction of simultaneous stimulation with overall smaller SSSEP amplitudes and poorer behavioral performance in the within-hand condition. Spatial proximity of stimulation did not affect the magnitude of attentional gain, it resulted in the occurrence of an intermodulation frequency indicating integrative stimulus processing in the within-hand condition. Obviously, while this integrative stimulus processing resulted in or was a result of greater intra-hemispheric competitive interactions, attention acted additively as a signal gain, which was independent of spatial competition.
我们研究了在躯体感觉持续空间注意过程中处理资源的竞争性神经相互作用。参与者在不同频率下同时接受振动触觉刺激，刺激部位为非相邻的左手手指（手内）或两只手的手指（手间），持续4500毫秒，以诱发稳态体感诱发电位（SSSEPs）。他们分别关注一个或两个受刺激位置，并对持续信息流中嵌入的罕见事件做出反应。行为和电生理结果显示，在同时刺激的情况下存在竞争性相互作用，在手内条件下，SSSEP振幅总体较小，行为表现较差。刺激的空间邻近性并不影响注意增益的大小，它导致了互调频率的出现，这表明在手内条件下存在整合性刺激处理。显然，虽然这种整合性刺激处理导致了更大的半球内竞争性相互作用，或者是其结果，但注意作为信号增益以相加的方式起作用，这与空间竞争无关。
