Neuro-Imaging Support for the Use of Audio to Represent Geospatial Location in Cartographic Design

Abstract

Audio has the capacity to display geospatial data. As auditory display design grapples with the challenge of aligning the spatial dimensions of the data with the dimensions of the display, this dissertation investigates the role of time in auditory geographic maps. Three auditory map types translate geospatial data into collections of musical notes, and arrangement of those notes in time vary across three map types: sequential, augmented-sequential , and concurrent. Behavioral and neuroimaging methods assess the auditory symbology. A behavioral task establishes geographic context, and neuroimaging provides a quantitative measure of brain responses to the behavioral task under recall and active listening response conditions.

In both behavioral and neuroimaging data, two paired contrasts measure differences between the sequential and augmented-sequential map types, and between the augmented- sequential and concurrent map types. Behavioral data reveal differences in both response time and accuracy. Response times for the augmented-sequential map type are substantially longer in both contrasts under the active response condition. Accuracy is lower for concurrent maps than for augmented-sequential maps; response condition influences direction of differences in accuracy between the sequential and augmented-sequential map types. Neuroimaging data from functional magnetic resonance imaging (fMRI) show significant differences in blood-oxygenation level dependent (BOLD) response during map listening. The BOLD response is significantly stronger in the left auditory cortex and planum temporale for the concurrent map type in contrast to the augmented- sequential map type. And the response in the right auditory cortex and bilaterally in the visual cortex is significantly stronger for augmented-sequential maps in contrast to sequential maps. Results from this research provide empirical evidence to inform choices in the design of auditory cartographic displays, enriching the diversity of geographic map artifacts.