Rhythmic structure of reading and cross-modal priming effect of rhythm on grammatical judgements

Rhythm is a fundamental element of both music and speech, however, the effect of auditorily presented rhythm patterns on reading processes is neglected in the research. Here we present an event-related potentials study conducted using such cross-modal design. Additional novelty of the study is the implication of the Russian language. We found an increased P600 effect after regular rhythmic stimulation, which indicates grammatical judgment on neurophysiological level and has been previously shown in the context of auditory tasks. We also found that participants with high response accuracy were able to engage in regular motor rhythm during grammatical judgment tasks and this group also performed better on the meter detection test. These results suggest tight intermodal connections in the reading process as well as the existence of an internal rhythmic structure which is both involved in the reading process and might be synchronized with external rhythmic stimulation.