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PubMed · 8146588

Absolute sensitivity measured psychophysically and using auditory steady-state potentials.

C A Champlin·J O'Neal
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Abstract

Absolute thresholds were measured psychophysically (behaviorally) and physiologically in the same subjects. Psychophysical thresholds were obtained using a modified method of limits. Physiological thresholds were based on auditory steady-state potentials recorded from the scalp. The stimuli for both types of test were click trains, periodic tone bursts and amplitude-modulated tones. The center frequency of the bursts and amplitude-modulated tones was 480 or 2000 Hz. It was found that psychophysical thresholds improved, and physiological thresholds worsened as the stimulus became more frequency-specific. Because of this interaction, the differences between psychophysical and physiological thresholds increased monotonically as a function of frequency specificity. Physiological thresholds obtained with the low-frequency stimuli were lower than those acquired with the high-frequency stimuli, while psychophysical thresholds obtained with the two frequencies were essentially the same.

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Acoustic StimulationAdultAuditory ThresholdElectric StimulationElectrodesEvoked Potentials, AuditoryFemaleFunctional LateralityHumansMalePsychophysicsClinical TrialComparative StudyJournal ArticleRandomized Controlled TrialResearch Support, Non-U.S. Gov't

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C A Champlin, J O'Neal. 1993. Absolute sensitivity measured psychophysically and using auditory steady-state potentials.. https://doi.org/10.3109/01050399309047475

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