The purpose of the present study was to study the tonal brain's speaker related to the audiovisual integration mechanisms for letters, i.e., for stimuli that have been previously associated through learning. The brain activations were detected with electroencephalogram (EEG), which is well suited for noninvasive identification of cortical activity and its accurate temporal dynamics. The audiovisual interaction was used as an indicator for investigating the automatic processing of simultaneously audiovisual integration related to the suprasegmental information in the tonal brain's speaker. Multisensory integration of letters (orthography) and speech sounds of tonal language in the human auditory association cortex of the tonal brain's speaker showed a strong dependency on the relative timing of the inputs. The critical role of input timing on multisensory integration has been demonstrated before at the neuronal level for naturally related visual and auditory signals. The critical role of input timing on multisensory integration has been demonstrated before at the neuronal level for naturally related visual and auditory signals.