Evidence of pitch processing in the N100m component of the auditory evoked field

• Published in: Hearing research Vol. 213; no. 1; pp. 88 - 98
• Main Authors: Seither-Preisler, Annemarie, Patterson, Roy, Krumbholz, Katrin, Seither, Stefan, Lütkenhöner, Bernd
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.03.2006; Elsevier
• Subjects: Acoustic Stimulation - methods; AEF; AIM; Analysis of Variance; Basilar Membrane - physiology; Biological and medical sciences; Cochlear Nerve - physiology; Computer Simulation; Ear and associated structures. Auditory pathways and centers. Hearing. Vocal organ. Phonation. Sound production. Echolocation; Ear, auditive nerve, cochleovestibular tract, facial nerve: diseases, semeiology; Evoked Potentials, Auditory - physiology; Female; Fundamental and applied biological sciences. Psychology; Humans; Magnetoencephalography; Male; Medical sciences; Models, Biological; N100m latency; Non tumoral diseases; Otorhinolaryngology. Stomatology; Pitch; Pitch Discrimination - physiology; Pitch Perception - physiology; Reaction Time; Relative phase; Vertebrates: nervous system and sense organs; AEF; BMM; RAND; Relative phase; SOA; AIM; EEG; AI; ALT; F0; MEG; POR; ERB; ANOVA; Pitch; RMS; SIN; NAP; N100m latency; Harmonic; Shape; Electrophysiology; Sound; Auditory nerve; Auditory evoked potential; Auditory pathway; Simulation model; Generator
• ISSN: 0378-5955; 1878-5891
• DOI: 10.1016/j.heares.2006.01.003

The latency of the N100m component of the auditory evoked field (AEF) is sensitive to the period and spectrum of a sound. However, little attention was paid so far to the wave shape at stimulus onset, which might have biased previous results. This problem was fixed in the present study by aligning the first major peaks in the acoustic waveforms. The stimuli were harmonic tones (spectral range: 800–5000 Hz) with periods corresponding to 100, 200, 400, and 800 Hz. The frequency components were in sine, alternating or random phase. Simulations with a computational model suggest that the auditory-nerve activity is strongly affected by both the period and the relative phase of the stimulus, whereas the output of the more central pitch processor only depends on the period. Our AEF data, recorded from the right hemisphere of seven subjects, are consistent with the latter prediction: The latency of the N100m depends on the period, but not on the relative phase of the stimulus components. This suggests that the N100m reflects temporal pitch extraction, not necessarily implying that the underlying generators are directly involved in this analysis.