Electrophysiological and behavioral measures of some speech contrasts in varied attention and noise

Publikation: Bidrag til tidsskriftTidsskriftartikelfagfællebedømt

This paper investigates the salience of speech contrasts in noise, in relation to how listening attention affects scalp-recorded cortical responses. The contrasts that were examined with consonant-vowel syllables, were place of articulation, vowel length and voice-onset time (VOT) and our analysis focuses on the correspondence between the effect of attention on the electrophysiology and the decrement in behavioral results when noise was added to the stimuli. Normal-hearing subjects (n=20) performed closed-set syllable identification in no noise, 0, 4 and 8 dB signal-noise ratio (SNR). Behavioral results showed that place of articulation was markedly affected by noise backgrounds while VOT was not. The same syllables were used in two electrophysiology conditions, where subjects attended to the stimuli, and also while their attention was diverted to a visual discrimination task. Differences in global field power between the attention conditions from each contrast showed that that the effect of attention was negligible for place of articulation. They implied offset encoding of vowel length and were early (starting at 117 ms), and of high amplitude (>3 microV) for VOT. There were significant correlations between the difference in syllable identification in no noise and 0 dB SNR and the electrophysiology results between attention conditions for the VOT contrast. Comparison of the two attention conditions with microstate analysis showed a significant difference in the duration of microstate class D. These results show differential integration of attention and syllable processing according to speech contrast and they suggest that there is correspondence between the salience of a contrast in noise and the effect of attention on the evoked electrical response.

Abbreviations: EEG Electroencephalography
; ERP Event Related Potential
; FDR False Discovery Rate
; GFP Global Field Power; ISI Interstimulus Interval; RMS Root-Mean Square
; SNR Signal-Noise Ratio
; SINFA Sequential Information Transfer Analysis; VOT Voice-Onset Time 

OriginalsprogEngelsk
TidsskriftHearing Research
Vol/bind373
Antal sider9
ISSN0378-5955
DOI
StatusUdgivet - 2019

ID: 209515310