FRIDAY MORNING, 20 MAY 2005 REGENCY E, 8:30 A.M. TO 12:00 ...

very limited and mostly based on different developmental trends. Tongue
movements were recorded using a magnetometer system. Speed and
movement paths were used to examine movement kinematics, including
different measures of stiffness. Preliminary results do not show any consistent
pattern across subjects, although some subjects did have systematic
differences in movement stiffness with stop consonants having stiffer
movements that fricatives. These results most likely reflect that fact that
speech is an over learned skill, so that any differences related to precision
are very small, or nonexistent, in adults, and probably only apparent in the
early stages of speech development. Work supported by NIH.
5pSC21. Haptic information enhances auditory speech perception.
Kristin M. Johannsdottir, Diana Gibrail, Gick Bryan, Ikegami Yoko
Dept. of Linguist., Univ. of British Columbia, Canada, and Jeff
Muehlbauer Univ. of British Columbia, Canada
Studies of tactile enhancement effects on auditory speech perception
Reed et al., JSHR, 1978, 1982, 1989 have traditionally used experienced,
pre-trained subjects. These studies have left unanswered the basic
questions of whether tactile enhancement of speech is a basic component
of human speech perception or a learned association Fowler, JPhon, 1986;
Diehl and Kluender, Ecol. Psych., 1989, and which aspects of the signal
are enhanced through this modality. The present study focuses exclusively
on tactile enhancement effects available to naive speakers. In a speechmasked
environment, naive subjects were tasked with identifying consonants
using the Tadoma method. Half of the stimuli were presented with
tactile input, and half without. The results show that all subjects gained
considerably from tactile information, although which part of the tactile
signal was most helpful varied by subject. The features that contributed
most to consonant identification were aspiration and voicing. Work supported
by NSERC.
5pSC22. Categorization of spectrally complex non-invariant auditory
stimuli in a computer game task. Lori Holt and Travis Wade Dept.
Psych., Carnegie Mellon Univ., 5000 Forbes Ave., Pittsburgh, PA 15213,
twade@andrew.cmu.edu
This study examined perceptual learning of spectrally complex nonspeech
auditory categories in an interactive multi-modal training paradigm.
Participants played a computer game in which they navigated
through a three-dimensional space while responding to animated characters
encountered along the way. Characters appearances in the game correlated
with distinctive sound category distributions, exemplars of which
repeated each time the characters were encountered. As the game progressed,
the speed and difficulty of required tasks increased and characters
became harder to identify visually, so quick identification of approaching
characters by sound patterns was, although never required or encouraged,
of gradually increasing benefit. After thirty minutes of play, participants
performed a categorization task, matching sounds to characters. Despite
not being informed of audio-visual correlations, participants exhibited reliable
learning of these patterns at post-test. Categorization accuracy was
related to several measures of game performance and category learning
was sensitive to category distribution differences modeling acoustic structures
of speech categories. Category knowledge resulting from the game
was qualitatively different from that gained from an explicit unsupervised
categorization task involving the same stimuli. Results are discussed with
respect to information sources and mechanisms involved in acquiring
complex, context-dependent auditory categories, including phonetic categories,
and to multi-modal statistical learning.
5pSC23. Acoustic correlates of non-modal phonation in telephone
speech. Tae-Jin Yoon Dept. of Linguist., Univ. of Illinois, 4080 FLB,
707 S. Mathews Ave., MC-168, Urbana, IL 61801, tyoon@uiuc.edu,
Jennifer Cole, Mark Hasegawa-Johnson, and Chilin Shih Univ. of
Illinois, Urbana, IL 61801
Non-modal phonation conveys both linguistic and paralinguistic information,
and is distinguished by acoustic source and filter features. Detecting
non-modal phonation in speech requires reliable F0 analysis, a problem
for telephone-band speech, where F0 analysis frequently fails. An
approach is demonstrated to the detection of creaky phonation in telephone
speech based on robust F0 and spectral analysis. The F0 analysis
relies on an autocorrelation algorithm applied to the inverse-filtered
speech signal and succeeds in regions of non-modal phonation where the
non-filtered F0 analysis typically fails. In addition to the extracted F0
values, spectral amplitude is measured at the first two harmonics (H1,
H2) and the first three formants (A1, A2, A3). F0 and spectral tilt are
measured from 300 samples of modal and creaky voice vowels, selected
from Switchboard telephone speech using auditory and visual criteria.
Results show successful F0 detection in creaky voice regions, with distinctive
low F0, and statistically significant differences between modal
and creaky voice in measures of spectral amplitude, especially for measures
based on H1. Our current work develops methods for the automatic
detection of creaky voicing in spontaneous speech based on the analysis
technique shown here. Work supported by NSF.
5pSC24. A consonant-vowel-consonant display as a computer-based
articulation training aid for the hearing impaired. Fansheng Meng,
Eugen Rodel, and Stephen Zahorian Dept. of Elec. and Comput. Eng.,
Old Dominion Univ., Norfolk, VA 23529
Computer-based visual speech training aids are potentially useful feedback
tools for hearing impaired people. In this paper, a training aid for the
articulation of short Consonant-Vowel-Consonant CVC words is presented
using an integrated real-time display of phonetic content and loudness.
Although not yet extensively tested with hearing-impaired listeners,
real-time signal processing has been developed, flow-mode displays have
been developed, and accuracy tests have been completed with a large
database of CVC short words. A combination of Hidden Markov Models
and time-delay neural networks are used as the primary method for the
acoustic-phonetic transformations used in the display. Work partially supported
by NSF grant BES-9977260.
5pSC25. Stop consonant perception in silent-center syllables. Mark
DeRuiter Univ. of Minnesota, 164 Pillsbury Dr. S.E., 115 Shevlin Hall,
Minneapolis, MN 55455, Virginia S. Ramachandran, and Sheryl J. Rosen
Wayne State Univ., Detroit, MI 48202
Silent-center SC syllables are consonant-vowel-consonant syllables
with the steady-state vowel portion excised from them. These syllables are
appealing for research of stop-consonants because they retain the complexity,
brevity, and rapid changes inherent in formant transitions while
presumably eliminating temporal masking by the vowel. However, questions
exist as to whether or not SC syllables are processed in the same
manner as their full-vowel FV counterparts i.e. are they processed as
speech units or as sounds?. Data is reviewed from a series of experiments
which examined listeners discrimination, labeling, and response time for
synthesized consonant-vowel-consonant syllables in FV and SC conditions.
Results from 3 experiments with typical listeners reveal that: 1
discrimination is significantly better in the SC condition; 2 consonant
labeling on a /bab/ to /dad/ continuum is poorer in the SC condition and is
significantly poorer at the category boundary; 3 discrimination responsetime
RT is significantly shorter in the SC condition. Labeling and discrimination
results reveal that listeners processed the stop-consonants in
these SC syllables in a less-categorical manner than in the FV syllables.
Taken together with significantly different response-times, these results
may indicate that listeners utilize a different mode of processing for SC
syllables.
2621 J. Acoust. Soc. Am., Vol. 117, No. 4, Pt. 2, April 2005 149th Meeting: Acoustical Society of America 2621
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