In order to examine why noise has reliable effects on delayed recall in a certain text-reading task, an episodic memory task was used with other memory tests in a study of road traffic noise and meaningful but irrelevant speech. Context-dependent memory (CDM) was tested and self-reports of affect were taken. Subjects were 96 high school students. Results show that both road traffic noise and meaningful irrelevant speech impair text recall. Retrieval in noise from semantic memory was also impaired. Attention was impaired by both noise sources, but attention did not mediate the noise effects on episodic memory. Recognition was not affected by noise. CDM was not shown. The lack of mediation by attention, and road traffic noise being as harmful as meaningful irrelevant speech, are discussed in relation to where in the input/storing/output sequence noise has its effect and what the distinctive feature of the disturbing noise is.
Abstract