Effects of background noise on inter-trial phase coherence and auditory N1-P2 responses to speech stimuli.
This study investigated the effects of a speech-babble background noise on inter-trial phase coherence (ITPC, also referred to as phase locking value (PLV)) and auditory event-related responses (AERP) to speech sounds. Specifically, we analyzed EEG data from 11 normal hearing subjects to examine whether ITPC can predict noise-induced variations in the obligatory N1-P2 complex response. N1-P2 amplitude and latency data were obtained for the /bu/syllable in quiet and noise listening conditions. ITPC data in delta, theta, and alpha frequency bands were calculated for the N1-P2 responses in the two passive listening conditions. Consistent with previous studies, background noise produced significant amplitude reduction and latency increase in N1 and P2, which were accompanied by significant ITPC decreases in all the three frequency bands. Correlation analyses further revealed that variations in ITPC were able to predict the amplitude and latency variations in N1-P2. The results suggest that trial-by-trial analysis of cortical neural synchrony is a valuable tool in understanding the modulatory effects of background noise on AERP measures.
Department of Speech-Language-Hearing Sciences, University of Minnesota, Minneapolis, MN 55455, USA.
Tess K
TK
Koerner
Department of Speech-Language-Hearing Sciences, University of Minnesota, Minneapolis, MN 55455, USA; Center for Neurobehavioral Development, University of Minnesota, Minneapolis, MN 55455, USA; Center for Applied and Translational Sensory Science, University of Minnesota, Minneapolis, MN 55455, USA. Electronic address: zhanglab@umn.edu.
Yang
Y
Zhang
D000161:Acoustic Stimulation; D000328:Adult; D001303:Auditory Cortex / Q000502:physiology; D001307:Auditory Perception / Q000502:physiology; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory / Q000502:physiology; D005260:Female; D064368:Healthy Volunteers; D006309:Hearing; D006801:Humans; D008297:Male; D009622:Noise; D010700:Phonetics; D015203:Reproducibility of Results; D013060:Speech / Q000502:physiology*; D013067:Speech Perception / Q000502:physiology; D055815:Young Adult
AERP; ITPC; PLV; Speech-in-noise perception; Time-frequency analysis