Research On Velocity Discrimination Perception In Circular Motion And Related EEG

The auditory perception of moving sound sources is an important function of the human auditory system.However,due to the limited ability of human auditory discrimination,there is an auditory perception threshold.The auditory perception thresholds of motion sound sources include motion/static judgment threshold（minimum audible motion angle）and velocity discrimination threshold.This paper simulates different acoustic scenarios by controlling the size and reverberation time of the room,and systematically studies the behavioral performance and related behaviors of the reverberation field horizontal plane and lateral vertical plane motion sound source velocity discrimination threshold through psychoacoustic experiments and EEG experiments.In the psychoacoustics experiment,the continuous moving sound sources on the horizontal plane and the lateral vertical plane under different reverberation times were first synthesized by the simulation algorithm;then,the two down one up adaptive method was used to analyze the sound sources with different reference velocities in different reverberation fields.Movement velocity discrimination thresholds were measured in response to two-interval two-forced choice（2I 2AFC）.The experimental results of the velocity discrimination threshold between horizontal and lateral vertical planes show that:（1）the velocity discrimination threshold of moving sound sources increases with the increase of reverberation time;（2）the velocity discrimination threshold of moving sound sources increases with the increase of reference velocity;At the same time,in the free field(T₆₀=0s),the weber fraction of the horizontal plane and the lateral vertical plane decreases with the increase of the reference velocity,which is in line with weber’s law;（3）In the case of different reverberation fields,the velocity discrimination threshold on the lateral vertical plane and the horizontal plane velocity discrimination thresholds were not significantly different.In the auditory brainwave experiment,the physiological mechanism of velocity discrimination and perception of circular motion under the condition of reverberation field was studied by using various components of event-related potential（ERP）as objective indicators.The statistical results show that:（1）The reverberation time has no significant effect on the amplitude of P2;the amplitude of P2 increases with the increase of the velocity of the sound source.The P2 latency increased with the increase of the reverberation time and decreased with the increase of the velocity of the sound source.（2）The P300 amplitude decreased with the increase of the reverberation time;when the acoustic stimulation durations were not much different,the stimulation-induced P300 amplitude increased with the increase of the sound source moving velocity.The P300 latency increased with the increase of the reverberation time and decreased with the increase of the velocity of the sound source.（3）When T₆₀=0s,the amplitude of mismatch negativity increases with the increase of the velocity of the sound source.Under different reverberation time conditions,the MMN latency decreased with the increase of the sound source moving velocity.（4）The amplitudes of P2and P300 reflect the contralateral advantage.The work of this paper contributes to an in-depth understanding of the physiological and psychological mechanisms of the perception of the velocity of circular motion under different reverberation field conditions,and provides a certain cognitive basis for the effective simulation of moving sound sources in virtual auditory technology.