The influence of background sounds and rehearsal language on the irrelevant speech effect of mandarin native speakers

Background sounds disrupt short-term memory, even if the target information is presented visually. Since speech has been found to be the most disruptive sound, this phenomenon was termed the Irrelevant Speech Effect (ISE). The previous study of this project found that the ISE depends not only on the presented language of background sounds but also on whether it coincided with participants' native language. The presented study further investigated whether this finding was caused by the interference from same language in rehearsal and background sounds. Each participant (N = 46) was asked to memorize the order of nine-item sequences (nine digits and nine Latin letters) which were presented visually under different background sounds (pink noise, Mandarin and English). Participants memorized fewer Latin letters than digits in all sound conditions and memorized the fewest items under participants’ native language Mandarin. However, only the types of backgrounds have a statistically significant effect on the size of ISE. The results suggest that the effects of rehearsal language and background sound on the accuracy of the short-term memory task are unrelated, and the size of the ISE may not be enhanced by the coincidence of rehearsal language and background sound.