The attentional boost effect with verbal materials.

Study stimuli presented at the same time as unrelated targets in a detection task are better remembered than stimuli presented with distractors. This attentional boost effect (ABE) has been found with pictorial (Swallow & Jiang, 2010) and more recently verbal materials (Spataro, Mulligan, & Rossi-Arnaud, 2013). The present experiments examine the generality of the ABE with verbal materials and critically assess the perceptual encoding hypothesis, the notion that the memory benefits are due to enhanced encoding of the perceptual properties of the study stimulus. Experiments 1 and 3 demonstrated an ABE with visual study items, comparable in size whether the recognition test was visual or auditory. Experiments 2 and 3 established an ABE for auditory study stimuli that was again equivalent for auditory and visual recognition tests. Experiments 4 and 5 found an ABE on the test of free recall. Finally, the ABE was greater for high-frequency than low-frequency words. The results demonstrate the generality of the ABE over study and test modality, and over memory tests (recognition and free recall), while also documenting a moderating factor (word frequency). Importantly, the representational basis for the ABE with verbal materials appears to be abstract, or amodal, rather than modality specific.