In perceiving speech, a hearer may divide the utterance into predictable units. In the present investigation of these units, an alleged phenomenon (the resistance of the hearer to perceive extraneous auditory stimuli) was employed. It was argued that this resistance caused the hearer to perceive the irrelevant stimulus, if at all, primarily at the juncture of major units. Also investigated was the interaction between the verbal materials used and the perception of the extraneous stimulus (a click). The subjects were eight kindergarten and eight second grade children. The verbal materials, spoken to the children by an adult, were sentences and nonsentence strings of words. Also clicking sounds were made. The children were asked to tell where in the sentence or string of words the click occurred. The results indicated that a greater magnitude of displacement of the click from its actual position occurred for the sentences than for the nonsentence material. The younger children tended to preposition the click. In both age groups, there was a tendency for click location to be prepositioned in nonsentences and postpositioned in sentences. Also, as has been observed with adults, the preception of the click tended to migrate towards major unit boundaries in the sentence material. These boundaries were determined by Rulon Wells' immediate constituent analysis. (WD)