Does the 40-Hz auditory steady-state response show the binaural masking level difference?
In contrast to the transient (N1-P2) and steady-state (<20 Hz) cortical responses, neither the transient (auditory brain stem response) nor the steady-state (80 Hz) brain stem responses show the binaural masking level difference (BMLD). This study determined behavioral and 40-Hz auditory steady-state response (ASSR) BMLDs for both signal and noise interaural inversions. Results showed clear behavioral BMLD but no 40-Hz ASSR BMLD. However, ASSR amplitudes were significantly smaller in dichotic compared with diotic conditions. Thus, although 40-Hz ASSR thresholds do not reflect the BMLD, the amplitude suppression under dichotic conditions may be a precursor to the subsequent <20-Hz ASSR and behavioral BMLDs.
Ishida
Ieda Maria
IM
School of Audiology and Speech Sciences, The University of British Columbia, Vancouver, BC, Canada.
Stapells
David R
DR
D000161:Acoustic Stimulation; D000328:Adult; D001303:Auditory Cortex / Q000502:physiology; D001306:Auditory Pathways / Q000502:physiology; D001309:Auditory Threshold / Q000502:physiology; D001933:Brain Stem / Q000502:physiology; D004007:Dichotic Listening Tests; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010470:Perceptual Masking / Q000502:physiology*; D012815:Signal Processing, Computer-Assisted; D013018:Sound Spectrography; D013067:Speech Perception / Q000502:physiology; D013788:Thalamus / Q000502:physiology