Preliminary Investigation of the Passively Evoked N400 as a Tool for Estimating Speech-in-Noise Thresholds.

Am J Audiol

School of Human Communication Disorders, Dalhousie University, Halifax, Nova Scotia, CanadaSchool of Psychology, Dalhousie University, Halifax, Nova Scotia, CanadaDivision of Otolaryngology, Queen Elizabeth II Health Sciences Centre, Halifax, Nova Scotia, CanadaBiomedical Translational Imaging Centre, IWK Health Centre, Halifax, Nova Scotia, Canada.

Published: December 2016

Purpose: Speech-in-noise testing relies on a number of factors beyond the auditory system, such as cognitive function, compliance, and motor function. It may be possible to avoid these limitations by using electroencephalography. The present study explored this possibility using the N400.

Method: Eleven adults with typical hearing heard high-constraint sentences with congruent and incongruent terminal words in the presence of speech-shaped noise. Participants ignored all auditory stimulation and watched a video. The signal-to-noise ratio (SNR) was varied around each participant's behavioral threshold during electroencephalography recording. Speech was also heard in quiet.

Results: The amplitude of the N400 effect exhibited a nonlinear relationship with SNR. In the presence of background noise, amplitude decreased from high (+4 dB) to low (+1 dB) SNR but increased dramatically at threshold before decreasing again at subthreshold SNR (-2 dB).

Conclusions: The SNR of speech in noise modulates the amplitude of the N400 effect to semantic anomalies in a nonlinear fashion. These results are the first to demonstrate modulation of the passively evoked N400 by SNR in speech-shaped noise and represent a first step toward the end goal of developing an N400-based physiological metric for speech-in-noise testing.

Download full-text PDF

Source
http://dx.doi.org/10.1044/2016_AJA-15-0080DOI Listing

Publication Analysis

Top Keywords

passively evoked
8
evoked n400
8
speech-in-noise testing
8
speech-shaped noise
8
amplitude n400
8
snr
6
preliminary investigation
4
investigation passively
4
n400
4
n400 tool
4

Similar Publications

Dexterous motor skills, like those needed for playing musical instruments and sports, require the somatosensory system to accurately and rapidly process somatosensory information from multiple body parts. This is challenging due to the convergence of afferent inputs from different body parts into a single neuron and the overlapping representation of neighboring body parts in the somatosensory cortices. How do trained individuals, such as pianists and athletes, manage this? Here, a series of five experiments with pianists and nonmusicians (female and male) shows that pianists have enhanced inhibitory function in the somatosensory system, which isolates the processing of somatosensory afferent inputs from each finger.

View Article and Find Full Text PDF

Stimulation of the ventromedial prefrontal cortex and the perception of affective faces. An effective connectivity analysis.

Biol Psychol

December 2024

Institute for Biomagnetism and Biosignal Analysis, University of Münster, Germany; Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster, Germany, Krakow, 2024-12-28.

The ventromedial prefrontal cortex is widely linked with emotional phenomena, including appraisal, modulation, and reward processing. Its perigenual part is suggested to mediate the appetitive value of stimulation. In our previous study, besides changes in evoked MEG responses, we were able to induce an apparent behavioral bias toward more positive valence while interpreting the ambiguous, morphed faces after the effect of excitatory tDCS stimulation of the perigenual ventromedial cortex (pgVM).

View Article and Find Full Text PDF

The N1 auditory evoked potential amplitude depends heavily on the inter-stimulus interval (ISI). Typically, shorter ISIs result in reduced N1 amplitudes, suggesting a decreased neural response with high stimulus presentation rates. However, an exception known as N1 facilitation occurs with very brief ISIs (∼150-500 ms), where the N1 amplitude increases.

View Article and Find Full Text PDF

Spike-wave-discharges (SWD) are the electrophysiological hallmark of absence epilepsy. SWD are generated in the thalamo-cortical network and a seizure onset zone was identified in the somatosensory cortex (S1). We have shown before that inhibition of the centromedian thalamic nucleus (CM) in GAERS rats resulted in a selective suppression of the spike component while rhythmic cortical 5-9 Hz oscillations remained present.

View Article and Find Full Text PDF

Military personnel often encounter situations that can trigger acute stress, which may affect operational performance. Therefore, it is important to examine stress responses in controlled environments to obtain more insights in performance-influencing effects of acute stress. This study investigated the impact of passive heat exposure combined with virtual combat scenarios on cardiovascular and psychophysiological parameters in a controlled setting.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!