Event-related potentials index segmentation of nonsense sounds

To understand the world around us, continuous streams of information including speech must be segmented into units that can be mapped onto stored representations. Recent evidence has shown that event-related potentials (ERPs) can index the online segmentation of sound streams. In the current study, listeners were trained to recognize sequences of three nonsense sounds that could not easily be rehearsed. Beginning 40 ms after onset, sequence-initial sounds elicited a larger amplitude negativity after compared to before training. This difference was not evident for medial or final sounds in the sequences. Across studies, ERP segmentation effects are remarkably similar regardless of the available segmentation cues and nature of the continuous streams. These results indicate the preferential processing of sequence-initial information is not domain specific and instead implicate a more general cognitive mechanism such as temporally selective attention. (C) 2008 Elsevier Ltd. All rights reserved.