Matching Items (4)
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- All Subjects: Sound Localization
- Creators: Zhou, Yi
- Creators: Department of Speech and Hearing Science
- Member of: Theses and Dissertations
- Status: Published
Description
This thesis investigated the impact of word complexity as measured through the Proportion of Whole Word Proximity (PWP; Ingram 2002) on consonant correctness as measured by the Percentage of Correct Consonants (PCC; Shriberg & Kwiatkowski 1980) on the spoken words of monolingual Spanish-speaking children. The effect of word complexity on consonant correctness has previously been studied on English-speaking children (Knodel 2012); the present study extends this line of research to determine if it can be appropriately applied to Spanish. Language samples from a previous study were used (Hase, 2010) in which Spanish-speaking children were given two articulation assessments: Evaluación fonológica del habla infantil (FON; Bosch Galceran, 2004), and the Spanish Test of Articulation for Children Under Three Years of Age (STAR; Bunta, 2002). It was hypothesized that word complexity would affect a Spanish-speaking child’s productions of correct consonants as was seen for the English- speaking children studied. This hypothesis was supported for 10 out of the 14 children. The pattern of word complexity found for Spanish was as follows: CVCV > CVCVC, Tri-syllables no clusters > Disyllable words with clusters.
ContributorsPurinton, Kaitlyn Lisa (Author) / Ingram, David (Thesis director) / Dixon, Dixon (Committee member) / Barlow, Jessica (Committee member) / Barrett, The Honors College (Contributor) / Department of Speech and Hearing Science (Contributor) / School of International Letters and Cultures (Contributor)
Created2013-12
Description
Head turning is a common sound localization strategy in primates. A novel system that can track head movement and acoustic signals received at the entrance to the ear canal was tested to obtain binaural sound localization information during fast head movement of marmoset monkey. Analysis of binaural information was conducted with a focus on inter-aural level difference (ILD) and inter-aural time difference (ITD) at various head positions over time. The results showed that during fast head turns, the ITDs showed significant and clear changes in trajectory in response to low frequency stimuli. However, significant phase ambiguity occurred at frequencies greater than 2 kHz. Analysis of ITD and ILD information with animal vocalization as the stimulus was also tested. The results indicated that ILDs may provide more information in understanding the dynamics of head movement in response to animal vocalizations in the environment. The primary significance of this experimentation is the successful implementation of a system capable of simultaneously recording head movement and acoustic signals at the ear canals. The collected data provides insight into the usefulness of ITD and ILD as binaural cues during head movement.
ContributorsLabban, Kyle John (Author) / Zhou, Yi (Thesis director) / Buneo, Christopher (Committee member) / Dorman, Michael (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Sound localization can be difficult in a reverberant environment. Fortunately listeners can utilize various perceptual compensatory mechanisms to increase the reliability of sound localization when provided with ambiguous physical evidence. For example, the directional information of echoes can be perceptually suppressed by the direct sound to achieve a single, fused auditory event in a process called the precedence effect (Litovsky et al., 1999). Visual cues also influence sound localization through a phenomenon known as the ventriloquist effect. It is classically demonstrated by a puppeteer who speaks without visible lip movements while moving the mouth of a puppet synchronously with his/her speech (Gelder and Bertelson, 2003). If the ventriloquist is successful, sound will be “captured” by vision and be perceived to be originating at the location of the puppet. This thesis investigates the influence of vision on the spatial localization of audio-visual stimuli. Participants seated in a sound-attenuated room indicated their perceived locations of either ISI or level-difference stimuli in free field conditions. Two types of stereophonic phantom sound sources, created by modulating the inter-stimulus time interval (ISI) or level difference between two loudspeakers, were used as auditory stimuli. The results showed that the light cues influenced auditory spatial perception to a greater extent for the ISI stimuli than the level difference stimuli. A binaural signal analysis further revealed that the greater visual bias for the ISI phantom sound sources was correlated with the increasingly ambiguous binaural cues of the ISI signals. This finding suggests that when sound localization cues are unreliable, perceptual decisions become increasingly biased towards vision for finding a sound source. These results support the cue saliency theory underlying cross-modal bias and extend this theory to include stereophonic phantom sound sources.
ContributorsMontagne, Christopher (Author) / Zhou, Yi (Thesis advisor) / Buneo, Christopher A (Thesis advisor) / Yost, William A. (Committee member) / Arizona State University (Publisher)
Created2015
Description
To localize different sound sources in an environment, the auditory system analyzes acoustic properties of sounds reaching the ears to determine the exact location of a sound source. Successful sound localization is important for improving signal detection and speech intelligibility in a noisy environment. Sound localization is not a uni-sensory experience, and can be influenced by visual information (e.g., the ventriloquist effect). Vision provides contexts and organizes the auditory space for the auditory system. This investigation tracks eye movement of human subjects using a non-invasive eye-tracking system and evaluates the impact of visual stimulation on localization of a phantom sound source generated through timing-based stereophony. It was hypothesized that gaze movement could reveal the way in which visual stimulation (LED lights) shifts the perception of a sound source. However, the results show that subjects do not always move their gaze towards the light direction even when they experience strong visual capture. On average, the gaze direction indicates the perceived sound location with and without light stimulation.
ContributorsFlores, Nancy Gloria (Author) / Zhou, Yi (Thesis director) / Azuma, Tamiko (Committee member) / Department of Speech and Hearing Science (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05