Previous studies have shown that visual attention effect can spread to the task‐irrelevant auditory modality automatically through either the stimulus‐driven binding process or the representation‐driven priming process. Using an attentional blink paradigm, the present study investigated whether the long‐latency stimulus‐driven and representation‐driven cross‐modal spread of attention would be inhibited or facilitated when the attentional resources operating at the post‐perceptual stage of processing are inadequate, whereas ensuring all visual stimuli were spatially attended and the representations of visual target object categories were activated, which were previously thought to be the only endogenous prerequisites for triggering cross‐modal spread of attention. The results demonstrated that both types of attentional spreading were completely suppressed during the attentional blink interval but were highly prominent outside the attentional blink interval, with the stimulus‐driven process being independent of, whereas the representation‐driven process being dependent on, audiovisual semantic congruency. These findings provide the first evidence that the occurrences of both stimulus‐driven and representation‐driven spread of attention are contingent on the amount of post‐perceptual attentional resources responsible for the late consolidation processing of visual stimuli, whereas the early detection of visual stimuli and the top‐down activation of the visual representations are not the sole endogenous prerequisites for triggering any types of cross‐modal attentional spreading.

The present study recorded event-related potentials (ERPs) in a visual object-recognition task under the attentional blink paradigm to explore the temporal dynamics of the cross-modal boost on attentional blink and whether this auditory benefit would be modulated by semantic congruency between T2 and the simultaneous sound. Behaviorally, the present study showed that not only a semantically congruent but also a semantically incongruent sound improved T2 discrimination during the attentional blink interval, whereas the enhancement was larger for the congruent sound. The ERP results revealed that the behavioral improvements induced by both the semantically congruent and incongruent sounds were closely associated with an early cross-modal interaction on the occipital N195 (192–228 ms). In contrast, the lower T2 accuracy for the incongruent than congruent condition was accompanied by a larger late occurring cento-parietal N440 (424–448 ms). These findings suggest that the cross-modal boost on attentional blink is hierarchical: the task-irrelevant but simultaneous sound, irrespective of its semantic relevance, firstly enables T2 to escape the attentional blink via cross-modally strengthening the early stage of visual object-recognition processing, whereas the semantic conflict of the sound begins to interfere with visual awareness only at a later stage when the representation of visual object is extracted.

Selective attention to visual stimuli can spread cross-modally to task-irrelevant auditory stimuli through either the stimulus-driven binding mechanism or the representation-driven priming mechanism. The stimulus-driven attentional spreading occurs whenever a task-irrelevant sound is delivered simultaneously with a spatially attended visual stimulus, whereas the representation-driven attentional spreading occurs only when the object representation of the sound is congruent with that of the to-be-attended visual object. The current study recorded event-related potentials in a space-selective visual object-recognition task to examine the exact roles of spacebased visual selective attention in both the stimulus-driven and representation-driven cross-modal attentional spreading, which remain controversial in the literature. Our results yielded that the representation-driven auditory Nd component (200-400 ms after sound onset) did not differ according to whether the peripheral visual representations of audiovisual target objects were spatially attended or not, but was decreased when the auditory representations of target objects were presented alone. In contrast, the stimulus-driven auditory Nd component (200-300 ms) was decreased but still prominent when the peripheral visual constituents of audiovisual nontarget objects were spatially unattended. These findings demonstrate not only that the representation-driven attentional spreading is independent of space-based visual selective attention and benefits in an all-or-nothing manner from object-based visual selection for actually presented visual representations of target objects, but also that although the stimulus-driven attentional spreading is modulated by space-based visual selective attention, attending to visual modality per se is more likely to be the endogenous determinant of the stimulus-driven attentional spreading.

We performed a theoretical investigation on the properties of iron–acceptor impurity pairs (Fe–A, with A=B, Al, Ga, and In) in silicon. The calculations were performed within the framework of an ionic model, including elastic and electrostatic interactions. In contrast to the conventional point charge ionic model, our model includes a correction to the electrostatic interaction that takes into account the valence electronic cloud polarization, which adds a short range, attractive interaction to Fe–A pair bonding, and includes the silicon lattice relaxation due to the atomic size difference between the acceptor and the lattice atoms. Our results are in good agreement with the experimental trends among the Fe–A pairs, describing the increase in the pair donor energy level with increasing A principal quantum number and decreasing pair separation distance, and the pair configurational symmetries.

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