Matching Items (4)
Filtering by
- All Subjects: Auditory Feedback
- Creators: Daliri, Ayoub
Description
The objective of this study was to analyze the auditory feedback system and the pitch-shift reflex in relation to vibrato. 11 subjects (female n = 8, male n = 3) without speech, hearing, or neurological disorders were used. Compensation magnitude, adaptation magnitude, relative response phase, and passive and active perception were recorded when the subjects were subjected to auditory feedback perturbed by phasic amplitude and F0 modulation, or “vibrato”. “Tremolo,” or phasic amplitude modulation, was used as a control. Significant correlation was found between the ability to perceive vibrato and tremolo in active trials and the ability to perceive in passive trials (p=0.01). Passive perceptions were lower (more sensitive) than active perceptions (p< 0.01). Adaptation vibrato trials showed significant modulation magnitude (p=0.031), while tremolo did not. The two conditions were significantly different (p<0.01). There was significant phase change for both tremolo and vibrato, but vibrato phase change was greater, nearly 180° (p<0.01). In the compensation trials, the modulation change from control to vibrato trials was significantly greater than the change from control to tremolo (p=0.01). Vibrato and tremolo also had significantly different average phase change (p<0.01). It can be concluded that the auditory feedback system tries to cancel out dynamic pitch perturbations by cancelling them out out-of-phase. Similar systems must be used to adapt and to compensate to vibrato. Despite the auditory feedback system’s online monitoring, the passive perception was still better than active perception, possibly because it required only one task (perceiving) rather than two (perceiving and producing). The pitch-shift reflex compensates to the sensitivity of the auditory feedback system, as shown by the increased perception of vibrato over tremolo.
ContributorsHiggins, Alexis Brittany (Author) / Daliri, Ayoub (Thesis director) / Liss, Julie (Committee member) / Luo, Xin (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
During speech, the brain is constantly processing and monitoring speech output through the auditory feedback loop to ensure correct and accurate speech. If the speech signal is experimentally altered/perturbed while speaking, the brain compensates for the perturbations by changing speech output in the opposite direction of the perturbations. In this study, we designed an experiment that examined the compensatory responses in response to unexpected vowel perturbations during speech. We applied two types of perturbations. In one condition, the vowel /ɛ/ was perturbed toward the vowel /æ/ by simultaneously shifting both the first formant (F1) and the second formant (F2) at 3 different levels (.5=small, 1=medium, and 1.5=large shifts). In another condition, the vowel /ɛ/ was perturbed by shifting F1 at 3 different levels (small, medium, and large shifts). Our results showed that there was a significant perturbation-type effect, with participants compensating more in response to perturbation that shifted /ɛ/ toward /æ/. In addition, we found that there was a significant level effect, with the compensatory responses to level .5 being significantly smaller than the compensatory responses to levels 1 and 1.5, regardless of the perturbation pathway. We also found that responses to shift level 1 and shift level 1.5 did not differ. Overall, our results highlighted the importance of the auditory feedback loop during speech production and how the brain is more sensitive to auditory errors that change a vowel category (e.g., /ɛ/ to /æ/).
ContributorsFitzgerald, Lacee (Author) / Daliri, Ayoub (Thesis director) / Corianne, Rogalsky (Committee member) / College of Health Solutions (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
The brain continuously monitors speech output to detect potential errors between its sensory prediction and its sensory production (Daliri et al., 2020). When the brain encounters an error, it generates a corrective motor response, usually in the opposite direction, to reduce the effect of the error. Previous studies have shown that the type of auditory error received may impact a participant’s corrective response. In this study, we examined whether participants respond differently to categorical or non-categorical errors. We applied two types of perturbation in real-time by shifting the first formant (F1) and second formant (F2) at three different magnitudes. The vowel /ɛ/ was shifted toward the vowel /æ/ in the categorical perturbation condition. In the non-categorical perturbation condition, the vowel /ɛ/ was shifted to a sound outside of the vowel quadrilateral (increasing both F1 and F2). Our results showed that participants responded to the categorical perturbation while they did not respond to the non-categorical perturbation. Additionally, we found that in the categorical perturbation condition, as the magnitude of the perturbation increased, the magnitude of the response increased. Overall, our results suggest that the brain may respond differently to categorical and non-categorical errors, and the brain is highly attuned to errors in speech.
ContributorsCincera, Kirsten Michelle (Author) / Daliri, Ayoub (Thesis director) / Azuma, Tamiko (Committee member) / School of Sustainability (Contributor) / College of Health Solutions (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
Past studies have shown that auditory feedback plays an important role in maintaining the speech production system. Typically, speakers compensate for auditory feedback alterations when the alterations persist over time (auditory motor adaptation). Our study focused on how to increase the rate of adaptation by using different auditory feedback conditions. For the present study, we recruited a total of 30 participants. We examined auditory motor adaptation after participants completed three conditions: Normal speaking, noise-masked speaking, and silent reading. The normal condition was used as a control condition. In the noise-masked condition, noise was added to the auditory feedback to completely mask speech outputs. In the silent reading condition, participants were instructed to silently read target words in their heads, then read the words out loud. We found that the learning rate in the noise-masked condition was lower than that in the normal condition. In contrast, participants adapted at a faster rate after they experience the silent reading condition. Overall, this study demonstrated that adaptation rate can be modified through pre-exposing participants to different types auditory-motor manipulations.
ContributorsNavarrete, Karina (Author) / Daliri, Ayoub (Thesis director) / Peter, Beate (Committee member) / College of Health Solutions (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05