Disruption of verbal-spatial serial memory by extraneous air-traffic speech

The disruptive impact of task-extraneous air-traffic radio speech on a task involving the serial-recall of combined verbal and spatial stimuli (7 letters and their locations) that were broadly analogous to information about aircraft callsigns and movements was examined. Regardless of the dimension to be recalled (identity or spatial location), accuracy was significantly disrupted by the air-traffic speech. Prior knowledge as to which dimension to recall did not affect accuracy and did not interact with the disruptive effect of air-traffic speech, but did extend the time to initiate a response to the first item. The results are discussed with reference to theories of the irrelevant sound effect and stimulus-dimension binding in short-term memory. The vulnerability of cognitive processing related to air-traffic management and similar work environments is also discussed.