Minimum Audible Movement Angle as a Function of the Azimuth and Elevation of the Source

Abstract

In the future auditory directional cues may enhance situational awareness in cockpits with head-coupled displays. This benefit would depend, however, on the pilot's ability to detect the direction of moving sounds at different locations in space. The present investigation examined this ability. Auditory motion acuity was measured by the minimum audible movement angle (MAMA): the minimum angle of travel required for detection of the direction of sound movement. Five experienced listeners were instructed to indicate the direction of travel of a sound source (broadband noise at 50 dBA) that moved at a velocity of 20 deg/s. Nine azimuth positions were tested at 0 deg elevation. Five elevations were then tested at 0 deg azimuth. Finally two azimuth positions were tested at an elevation of 80 deg. The position of the source did not significantly affect the MAMA for azimuth locations between +40 and -40 deg and elevations below 80 deg. Within this area the MAMA ranged between 1 and 2 deg. Outside this area the MAMA increased to 3 to 10 deg.

Get full access to this article

View all access options for this article.

References

Bauer, B. B. (1960). Phasor analysis of some stereophonic phenomena. Journal of the Acoustical Society of America. 33, 1536–1539.

Blauert, J. (1983). Spatial hearing: The psychophysics of human sound localization. Cambridge: MIT Press.

Calhoun, G. L. , Valencia, G. , and Furness, T. A. (1987). Three-dimensional auditory cue simulation for crew station design/evaluation. In Proceedings of the Human Factors Society 3/st Annual Meeting (pp. 1398–1402). Santa Monica, CA: Human Factors Society.

Doll, T. J. , Gerth, J. M. , Engelman, W. R. , and Folds, D. J. (1986). Development of simulated directional audio for cockpit applications (USAF Report AAMRL-TR-86-014). Wright-Patterson Air Force Base, OH.

Durlaeh, N. I. , and Coulbourn, H. S. (1978). Binaural phenomena. In E. C. Carterette and M. P. Friedman (Eds.), Handbook of perception: Vo/. IV. Hearing (pp. 365–466). New York: Academic.

Grantham, D. W. (1986). Detection and discrimination of simulated motion of auditory targets in the horizontal plane. Journal of the Acoustical Society of America, 79, 1939–1949.

Harris, J. D. , and Sergeant, R. L. (1971). Monaural/binaural minimum audible angles for a moving sound source. Journal of Speech and Hearing Research, 14, 618–629.

Levitt, H. (1970). Transformed up-down methods in psychoacoustics. Journal of the Acoustical Society of America, 49, 467–476.

Mills, A. W. (1958). On the minimum audible angle. Journal of the Acoustical Society of America, 61, 1264–1269.

10.

Mills, A. W. (1972). Auditory localization. In J. V. Tobias (Ed.), Foundations of modern auditory theory (Vol. 2, pp. 301–345). New York: Academic.

11.

Perrott, D. R. (1988). Auditory psychomotor coordination. In Proceedings of the Human Factors Society 32nd Annual Meeting (pp. 81–85). Santa Monica, CA: Human Factors Society.

12.

Perrott, D. R. , and Musicant, A. D. (1977). Minimum audible movement angle: Binaural localization of moving sound sources. Journal of the Acoustical Society of America, 62, 1463–1466.

13.

Perrott, D. R. , Saberi, K. , Brown, K. , and Strybel, T. Z. (1990). Auditory psychomotor coordination and visual search performance. Perception and Psychophysics, 48, 214–226.

14.

Perrott, D. R. , and Tucker, J. T. (1988). Minimum audible movement angle: Marking the end points of the path traveled by a moving sound source. Journal of the Acoustical Society of America, 85, 1773–1775.

15.

Sorkin, R. D. , Wightman, F. L. , Kistler, D. S. , and Elvers, G. C. (1989). An exploratory study on the use of movement-correlated cues in an auditory head-up display. Human Factors, 31, 161–166.

16.

Stevens, S. S. , and Newman, E. B. (1936). The localization of actual sources of sound. American Journal of Psychology, 48, 297–306.

17.

Wenzel, E. M. , Wightman, F. L. , and Foster, S. H. (1988). A virtual display system for conveying three-dimensional acoustic information. Proceedings of the Human Factors Society 32nd Annual Meeting (pp. 86–90). Santa Monica, CA: Human Factors Society.