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Item does not contain fulltext Many natural auditory signals, including music and language, change periodically. The effect of such auditory rhythms on the brain is unclear however. One widely held view, dynamic attending theory, proposes that the attentional system entrains to the rhythm and increases attention at moments of rhythmic salience. In support, 2 experiments reported here show reduced response times to visual letter strings shown at auditory rhythm peaks, compared with rhythm troughs. However, we argue that an account invoking the entrainment of general attention should further predict rhythm entrainment to also influence memory for visual stimuli. In 2 pseudoword memory experiments we find evidence against this prediction. Whether a pseudoword is shown during an auditory rhythm peak or not is irrelevant for its later recognition memory in silence. Other attention manipulations, dividing attention and focusing attention, did result in a memory effect. This raises doubts about the suggested attentional nature of rhythm entrainment. We interpret our findings as support for auditory rhythm perception being based on auditory-motor entrainment, not general attention entrainment. 12 p.

Item does not contain fulltext In the recent literature, the effects of noninvasive neurostimulation on cognitive functioning appear to lack consistency and replicability. We propose that such effects may be concealed unless dedicated, sensitive, and process-specific dependent measures are used. The expression and subsequent suppression of response capture are often studied using conflict tasks. Response-time distribution analyses have been argued to provide specific measures of the susceptibility to make fast impulsive response errors, as well as the proficiency of the selective suppression of these impulses. These measures of response capture and response inhibition are particularly sensitive to experimental manipulations and clinical deficiencies that are typically obfuscated in commonly used overall performance analyses. Recent work using structural and functional imaging techniques links these behavioral outcome measures to the integrity of frontostriatal networks. These studies suggest that the presupplementary motor area (pre-SMA) is linked to the susceptibility to response capture whereas the right inferior frontal cortex (rIFC) is associated with the selective suppression of action impulses. Here, we used repetitive transcranial magnetic stimulation (rTMS) to test the causal involvement of these two cortical areas in response capture and inhibition in the Simon task. Disruption of rIFC function specifically impaired selective suppression of conflicting action tendencies, whereas the anticipated increase of fast impulsive errors after perturbing pre-SMA function was not confirmed. These results provide a proof of principle of the notion that the selection of appropriate dependent measures is perhaps crucial to establish the effects of neurostimulation on specific cognitive functions. 13 p.