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Date of Award


Degree Type

Dissertation (On-Campus Access Only)

Degree Name

Doctor of Psychology (PsyD)

Committee Chair

Shawn E. Davis, Ph.D.

Second Advisor

Laura A. Edwards-Leeper, Ph.D.


The irrelevant sound effect (ISE) refers to the negative impact of background noise (e.g., chatter, music, speech, etc.) on short-term serial recall. The literature indicates that different types of sound may differentially impact serial recall performance. The present study is an examination of the differential ability of the human voice and musical instruments to produce the ISE. Participants completed a serial-recall task in the presence of silence, piano only, piano and euphonium, piano and voice without lyrics (i.e., humming), and piano and voice with lyrics. The results indicated the presence of the ISE, such that serial recall was significantly worse in the presence of lyrics compared with recall in the presence of silence, piano only, and piano and humming. A second focus of the present investigation was on individual difference factors, namely extroversion and bilingualism. Results indicated no significant differences in the degree of impairment caused by the ISE between introverts and extroverts or between bilinguals and monolinguals. The present results are discussed within the context of current ISE literature and suggestions for further investigation are presented.