An irrelevant speech effect with repeated and continuous background speech

The irrelevant speech effect is the impairment of task performance by the presentation of to-be-ignored speech stimuli. Typically, the irrelevant speech comprises a variety of sounds, but previous research (e.g., Jones, Madden, & Miles, 1992) has suggested that the deleterious effect of background speech is virtually eliminated if the speech comprises repetitions of a sound (e.g., "be, be, be") or a single continuous sound (e.g., "beeeeeee"). Four experiments are reported that challenge this finding. Experiments 1, 2, and 4 show a substantial impairment in serial recall performance in the presence of a repeated sound, and Experiments 3 and 4 show a similar impairment of serial recall in the presence of a continuous sound. The relevance of these findings to several explanations of the irrelevant speech effect is discussed.