Frequency and intensity effects on ear dominance for tone bursts

Area of Science:

• Auditory Neuroscience
• Psychoacoustics
• Human Hearing

Background:

• Normal-hearing individuals often exhibit ear dominance in pitch perception.
• This dominance is typically unaffected by significant interaural intensity differences.

Purpose of the Study:

• To investigate if ear dominance in pitch perception can be modified by manipulating dichotic stimuli.
• To examine the influence of frequency and interaural level differences on ear dominance.

Main Methods:

• Participants (N=20) listened to dichotic tone pairs at varying frequencies (0.4, 1.5, 3 kc/s) and interaural frequency differences (76, 224, 376 c/s).
• Interaural level differences (0, 15, 35 dB SPL) were applied, with the more intense tone at 80 dB SPL.
• Participants judged the pitch order ('high-low' or 'low-high') of the tone pairs.

Main Results:

• Ear dominance was found to be modifiable by changes in frequency location and interaural frequency difference.
• Interaural level differences impacted ear dominance across all frequencies, most prominently at low frequencies.
• The findings suggest a complex interplay of auditory system characteristics influencing ear dominance.

Conclusions:

• Ear dominance in dichotic pitch perception is not fixed and can be altered by stimulus parameters.
• Loudness perception, dichotic fusion, and frequency selectivity play roles in ear dominance.
• Binaural processes, not yet fully understood, also contribute to ear dominance in auditory perception.