DescriptionObjectives: Effective communication requires good speech perception abilities. Speech perception can be assessed with behavioral and electrophysiological methods. Relating these two types of measurements to each other can provide insights into the underlying cortical processes. The current study aimed (1) to develop a digit-based test battery suited for eliciting different speech-evoked cortical responses, and (2) to relate the speech-evoked cortical responses to behavioral measures of speech detection, discrimination, and comprehension. Design: Thirty young normal-hearing native Danish speakers with normal or corrected-to-normal vision participated. The digit-triplet lists from the Dantale-I speech corpus were used as stimulus material. All measurements were carried out in the presence of stationary speech-shaped noise at 67 dB(C) SPL. The behavioral measurements included speech detection thresholds (SDTs), speech recognition thresholds (SRTs) and speech comprehension scores (SCSs). For the electrophysiological measurements, multi-channel electroencephalography (EEG) recordings were performed. N100 and P300 responses were evoked using an active auditory oddball paradigm. N400 and Late Positive Complex (LPC) responses were evoked using congruent and incongruent digit sequences that were presented using audio-only or audio-visual paradigms. Results: All cortical EEG components could be evoked successfully. While no correlations between the SDT and SRT measurements and the N100 and P300 responses were found, the SCSs were correlated with the EEG responses to the congruent and incongruent digit sequences (r = -0.5, p < 0.05). Regarding the N400 and LPC measurements, there were significant amplitude differences between the congruent and incongruent digit conditions within the same paradigm (p < 0.05) but not across the two paradigms. Conclusions: The developed test battery was found to be usable and to produce reliable data. Because the audio-visual paradigm produced N400 and LPC responses very similar to those of the audio-only paradigm, it is expected to facilitate measurements of speech comprehension in clinical populations with severe hearing losses. Follow-up studies with hearing-impaired individuals will provide further insights into the consequences of hearing loss on cortical speech processing.
|Period||14. Jun 2021 → 9. Jul 2021|
|Event title||International Evoked Response Audiometry Study Group: Biennial Symposium 2021|
|Degree of Recognition||International|