Abstract: The event-related potentials (ERPs) were recorded in normal young subjects to investigate the calculational abilities with/without distractors, and shed light on the relationship of subitizing and counting. The results show that the discontinuity of the effects of the variation of distractors from the subitizing range to the counting range. The electrophysiological evidences support the idea of the two processes being implemented in different functional systems. The distractor’s number variation caused different type of ERPs waveforms in two enumeration processings. The results confirmed the argument that subitizing and counting are two functionally different processings in the brain, they can be differentiated by the different effects of the variation of distractors.

Key words: Subitizing, Counting, ERP (Event-related potential)