Line discrimination

Haptic devices

Horizontal lines in a sonified image can be difficult to discriminate dependent on the frequency range of the gaps that separate them. We ran a study in which sighted participants had to discriminate horizontal line soundscapes. Aside from a general linear pattern in which lines/frequencies further apart were more successfully discriminated, areas of interest within this general pattern showed marked drops in performance. Analysis of the frequencies of these areas of interest showed this occurred for octave and major fifth intervals. This implies that sonifications should pay attention to the imagery at such frequencies to give a true representation of the visual spatial components of the object. In a second part of the task the procedure was repeated but with simultaneous visual input. Performance was better than baseline when the visual and sonified input was congruous and inferior when incongruous. This demonstrates that provision of the sensory information in more than one modality has a positive effect on performance.