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P Zakarauskas

Publications and source records attributed to P Zakarauskas.

3 recordsLinked to original sources
PubMed2000

The auditory motion aftereffect: its tuning and specificity in the spatial and frequency domains.

In this paper, the auditory motion aftereffect (aMAE) was studied, using real moving sound as both the adapting and the test stimulus. The sound was generated by a loudspeaker mounted on a robot arm that was able to move quietly in three-dimensional space. A total of 7 subjects with normal hearing were tested in three experiments. The results from Experiment 1 showed a robust and reliable negative aMAE in all the subjects. After listening to a sound source moving repeatedly to the right, a stationary sound source was perceived to move to the left. The magnitude of the aMAE tended to increase with adapting velocity up to the highest velocity tested (20 degrees/sec). The aftereffect was largest when the adapting and the test stimuli had similar spatial location and frequency content. Offsetting the locations of the adapting and the test stimuli by 20 degrees reduced the size of the effect by about 50%. A similar decline occurred when the frequency of the adapting and the test stimuli differed by one octave. Our results suggest that the human auditory system possesses specialized mechanisms for detecting auditory motion in the spatial domain.

Acceleration↗
PubMed1991

Aural intensity for a moving source.

Considerable, highly specific information is available to the auditory system concerning the trajectory of a moving sound source. This paper delineates the set of stimuli that motion-sensitive systems might use. General expressions for the sound intensity, the interaural intensity difference, and their first time derivatives, are derived for a source moving along an arbitrary trajectory. The general expressions are then made explicit for three special cases of motion of an omnidirectional constant level source: a source moving directly away from or toward the observer, a source moving around the observer's head, and a source moving in a straight line across the auditory field of the observer. The later special case combine characteristics of the two first ones. The functions are plotted and their characteristics compared. The combination of all four functions provides a unique signature for each source trajectory. The first time derivative of the monaural spectrum level function is found to be directly proportional to the velocity scaled by the distance of the source for omnidirectional sources of constant intensity. This makes the first time derivative of the spectrum level especially attractive as a component of a specialized source detection system in the brain.

Auditory Perception↗