Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Date of Graduation

Spring 5-3-2013

Document Type


Degree Name

Doctor of Audiology (AuD)


Department of Communication Sciences and Disorders


Ayasakanta Rout


The primary objective of this study was to evaluate the effect of auditory and visual cognitive loads on the preferred background noise levels in normal-hearing listeners. This study investigated the preferable background noise levels (primary task) when normal hearing listeners were presented with auditory and/or visual cognitive distractions (secondary task). It was hypothesized that normal hearing listeners’ preferable background noise level would decrease in the presence of either distracter and that the synergistic effect of the two distracters would result in even lower preferable background noise level. Preferable background noise levels were measured on 24 normal-hearing listeners under four conditions. A 2x2 repeated measure ANOVA was performed with auditory and visual distraction (two levels each) as within-subject factors and the test order as a between-subjects factor. The results of the repeated measure ANOVA indicated significant main effect of auditory distraction. None of the interactions between auditory distraction, visual distraction and test order were reported to be significant. The interaction between auditory distraction and test order however, was near significant. Tests between subjects effects revealed no significant effect of test order. Pairwise comparison with Bonferroni correction revealed significantly higher preferable noise levels in the visual task and lower noise level in the auditory task. Results indicated that while attending to a visual cognitive task, normal hearing listeners were willing to put up with a higher background noise level than attending to an auditory task.



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