Matching Items (6)
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- All Subjects: EEG
- All Subjects: Speech And Hearing Sciences
- Creators: Daliri, Ayoub
Description
Speech perception and production are bidirectionally related, and they influence each other. The purpose of this study was to better understand the relationship between speech perception and speech production. It is known that applying auditory perturbations during speech production causes subjects to alter their productions (e.g., change their formant frequencies). In other words, previous studies have examined the effects of altered speech perception on speech production. However, in this study, we examined potential effects of speech production on speech perception. Subjects completed a block of a categorical perception task followed by a block of a speaking or a listening task followed by another block of the categorical perception task. Subjects completed three blocks of the speaking task and three blocks of the listening task. In the three blocks of a given task (speaking or listening) auditory feedback was 1) normal, 2) altered to be less variable, or 3) altered to be more variable. Unlike previous studies, we used subject’s own speech samples to generate speech stimuli for the perception task. For each categorical perception block, we calculated subject’s psychometric function and determined subject’s categorical boundary. The results showed that subjects’ perceptual boundary remained stable in all conditions and all blocks. Overall, our results did not provide evidence for the effects of speech production on speech perception.
ContributorsDaugherty, Allison (Author) / Daliri, Ayoub (Thesis director) / Rogalsky, Corianne (Committee member) / College of Health Solutions (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
The research question this thesis aims to answer is whether depressive symptoms of adolescents involved in romantic relationships are related to their rejection sensitivity. It was hypothesized that adolescents who have more rejection sensitivity, indicated by a bigger P3b response, will have more depressive symptoms. This hypothesis was tested by having adolescent couples attend a lab session in which they played a Social Rejection Task while EEG data was being collected. Rejection sensitivity was measured using the activity of the P3b ERP at the Pz electrode. The P3b ERP was chosen to measure rejection sensitivity as it has been used before to measure rejection sensitivity in previous ostracism studies. Depressive symptoms were measured using the 20-item Center for Epidemiological Studies Depression Scale (CES-D, Radloff, 1977). After running a multiple regression analysis, the results did not support the hypothesis; instead, the results showed no relationship between rejection sensitivity and depressive symptoms. The results are also contrary to similar literature which typically shows that the higher the rejection sensitivity, the greater the depressive symptoms.
ContributorsBiera, Alex (Author) / Dishion, Tom (Thesis director) / Ha, Thao (Committee member) / Shore, Danielle (Committee member) / Barrett, The Honors College (Contributor)
Created2015-05
Description
The cocktail party effect describes the brain’s natural ability to attend to a specific voice or audio source in a crowded room. Researchers have recently attempted to recreate this ability in hearing aid design using brain signals from invasive electrocorticography electrodes. The present study aims to find neural signatures of auditory attention to achieve this same goal with noninvasive electroencephalographic (EEG) methods. Five human participants participated in an auditory attention task. Participants listened to a series of four syllables followed by a fifth syllable (probe syllable). Participants were instructed to indicate whether or not the probe syllable was one of the four syllables played immediately before the probe syllable. Trials of this task were separated into conditions of playing the syllables in silence (Signal) and in background noise (Signal With Noise), and both behavioral and EEG data were recorded. EEG signals were analyzed with event-related potential and time-frequency analysis methods. The behavioral data indicated that participants performed better on the task during the “Signal” condition, which aligns with the challenges demonstrated in the cocktail party effect. The EEG analysis showed that the alpha band’s (9-13 Hz) inter-trial coherence could potentially indicate characteristics of the attended speech signal. These preliminary results suggest that EEG time-frequency analysis has the potential to reveal the neural signatures of auditory attention, which may allow for the design of a noninvasive, EEG-based hearing aid.
ContributorsLaBine, Alyssa (Author) / Daliri, Ayoub (Thesis director) / Chao, Saraching (Committee member) / Barrett, The Honors College (Contributor) / College of Health Solutions (Contributor) / Harrington Bioengineering Program (Contributor)
Created2023-05
Description
Previous research has showed that auditory modulation may be affected by pure tone
stimuli played prior to the onset of speech production. In this experiment, we are examining the
specificity of the auditory stimulus by implementing congruent and incongruent speech sounds in
addition to non-speech sound. Electroencephalography (EEG) data was recorded for eleven adult
subjects in both speaking (speech planning) and silent reading (no speech planning) conditions.
Data analysis was accomplished manually as well as via generation of a MATLAB code to
combine data sets and calculate auditory modulation (suppression). Results of the P200
modulation showed that modulation was larger for incongruent stimuli than congruent stimuli.
However, this was not the case for the N100 modulation. The data for pure tone could not be
analyzed because the intensity of this stimulus was substantially lower than that of the speech
stimuli. Overall, the results indicated that the P200 component plays a significant role in
processing stimuli and determining the relevance of stimuli; this result is consistent with role of
P200 component in high-level analysis of speech and perceptual processing. This experiment is
ongoing, and we hope to obtain data from more subjects to support the current findings.
stimuli played prior to the onset of speech production. In this experiment, we are examining the
specificity of the auditory stimulus by implementing congruent and incongruent speech sounds in
addition to non-speech sound. Electroencephalography (EEG) data was recorded for eleven adult
subjects in both speaking (speech planning) and silent reading (no speech planning) conditions.
Data analysis was accomplished manually as well as via generation of a MATLAB code to
combine data sets and calculate auditory modulation (suppression). Results of the P200
modulation showed that modulation was larger for incongruent stimuli than congruent stimuli.
However, this was not the case for the N100 modulation. The data for pure tone could not be
analyzed because the intensity of this stimulus was substantially lower than that of the speech
stimuli. Overall, the results indicated that the P200 component plays a significant role in
processing stimuli and determining the relevance of stimuli; this result is consistent with role of
P200 component in high-level analysis of speech and perceptual processing. This experiment is
ongoing, and we hope to obtain data from more subjects to support the current findings.
ContributorsTaylor, Megan Kathleen (Author) / Daliri, Ayoub (Thesis director) / Liss, Julie (Committee member) / School of Life Sciences (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
This longitudinal study aimed to determine whether significant differences existed between the baseline inaccurate signals of the /r/ phoneme for children that eventually acquire or do not acquire /r/. Seventeen participants ages 5-8 who had not acquired /r/ in any of its allophonic contexts were recorded approximately every 3 months from the age of recruitment until they either acquired /r/ in conversation (80% accuracy) or turned eight years old. The recorded audio files were trimmed and labelled using Praat, and signal processing was used to compare initial and final recordings of three allophonic variations of /r/ (vocalic, prevocalic, postvocalic) for each participant. Differences were described using Mel-log Spectral plots. For each age group, initial recordings of participants that eventually acquired /r/ were compared to those of participants that did not acquire /r/. Participants that had not acquired /r/ and had yet to turn eight years old were compared by whether they were perceived to be improving or perceived not to be improving. Significant differences in Mel-log spectral plots will be discussed, and the implications of baseline differences will be highlighted, specifically with respect to the feasibility of identifying predictive markers for acquisition
on-acquisition of the difficult /r/ phoneme.
on-acquisition of the difficult /r/ phoneme.
ContributorsHom, Rachel (Author) / Weinhold, Juliet (Thesis director) / Daliri, Ayoub (Committee member) / College of Health Solutions (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Transcranial Current Stimulation (TCS) is a long-established method of modulating neuronal activity in the brain. One type of this stimulation, transcranial alternating current stimulation (tACS), is able to entrain endogenous oscillations and result in behavioral change. In the present study, we used five stimulation conditions: tACS at three different frequencies (6Hz, 12Hz, and 22Hz), transcranial random noise stimulation (tRNS), and a no-stimulation sham condition. In all stimulation conditions, we recorded electroencephalographic data to investigate the link between different frequencies of tACS and their effects on brain oscillations. We recruited 12 healthy participants. Each participant completed 30 trials of the stimulation conditions. In a given trial, we recorded brain activity for 10 seconds, stimulated for 12 seconds, and recorded an additional 10 seconds of brain activity. The difference between the average oscillation power before and after a stimulation condition indicated change in oscillation amplitude due to the stimulation. Our results showed the stimulation conditions entrained brain activity of a sub-group of participants.
ContributorsChernicky, Jacob Garrett (Author) / Daliri, Ayoub (Thesis director) / Liss, Julie (Committee member) / School of Life Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05