Lesya Chorna, Ph.D.
Adjunct Associate Professor
- Milwaukee WI UNITED STATES
- Mathematics
Dr. Lesya Chorna specializes in both computer and mathematical modeling and computational stochastic methods.
Education, Licensure and Certification
Ph.D.
Applied Mathematics, Computer Modeling, Computation Statistics, Biomedical Engineering
Ternopil State Technical University
2006
Ph.D.
Mathematical Modeling, Computational Stochastic Methods
Ternopil State Technical University
1999
M.S.
Electronics Engineering
Ternopil State Technical University
1995
Biography
Memphis; a research assistant for the Department of Biomedical Engineering at Ternopil State Technical
University; and as an electronics engineer in the department of biomedical engineering at Ternopil State Technical University.
Areas of Expertise
Accomplishments
Certificate of Effective Management of Student Conduct
2009
Malcom Fraser Community Service Award
Awarded in recognition of valuable contribution to the field of Audiology and Speech-Language Pathology
2007
Event and Speaking Appearances
Morphometric Characteristics of the Vestibular Folds and their Functional Significance
Voice Foundation's 38th Annual Symposium: Care of the Professional Voice Philadelphia, PA, 2009
Vocal Steadiness in Spasmodic Dysphonia Revisited
13th Biennial Conference on Motor Speech: Motor Speech Disorders Austin, TX, 2006
Acoustic Features that Distinguish Canonical Syllables from Precursors Presentation
14th Biennial Conference on Motor Speech: Motor Speech Disorders and Speech Motor Control Monterey, CA, 2008
Speech Intelligibility in a Speaker with Idiopathic Parkinsons Disease Before and After Treatment
14th Biennial Conference on Motor Speech: Motor Speech Disorders and Speech Motor Control Monterey, CA, 2008
Vowel Harmonic Amplitude Differences in a Speaker with Hypokinetic Dysarthria
13th Biennial Conference on Motor Speech: Motor Speech Disorders Austin, TX, 2006
Selected Publications
Influence of Consonant Voicing Characteristics on Sentence Production in Abductor Versus Adductor Spasmodic Dysphonia
Journal of VoiceCannito, M.P., Chorna, L.B., Kahane, J.C., Dworkin, J.P.
2014
This study evaluated the hypotheses that sentence production by speakers with adductor (AD) and abductor (AB) spasmodic dysphonia (SD) may be differentially influenced by consonant voicing and manner features, in comparison with healthy, matched, nondysphonic controls. This was a prospective, single blind study, using a between-groups, repeated measures design for the independent variables of perceived voice quality and sentence duration. Sixteen subjects with ADSD and 10 subjects with ABSD, as well as 26 matched healthy controls produced four short, simple sentences that were systematically loaded with voiced or voiceless consonants of either obstruant or continuant manner categories. Experienced voice clinicians, who were "blind" as to speakers' group affixations, used visual analog scaling to judge the overall voice quality of each sentence. Acoustic sentence durations were also measured. Speakers with ABSD or ADSD demonstrated significantly poorer than normal voice quality on all sentences. Speakers with ABSD exhibited longer than normal duration for voiceless consonant sentences. Speakers with ADSD had poorer voice quality for voiced than for voiceless consonant sentences. Speakers with ABSD had longer durations for voiceless than for voiced consonant sentences. The two subtypes of SD exhibit differential performance on the basis of consonant voicing in short, simple sentences; however, each subgroup manifested voicing-related differences on a different variable (voice quality vs sentence duration). Findings suggest different underlying pathophysiological mechanisms for ABSD and ADSD. Findings also support inclusion of short, simple sentences containing voiced or voiceless consonants as part of the diagnostic protocol for SD, with measurement of sentence duration in addition to judments of voice quality severity.
Functional flexibility of infant vocalization and the emergence of language
Proceedings of the National Academy of SciencesOller, D.K., Buder, E.H., Ramsdell, H.L., Warlaumont, A.S., Chorna, L., Bakeman, R.
2013
We report on the emergence of functional flexibility in vocalizations of human infants. This vastly underappreciated capability becomes apparent when prelinguistic vocalizations express a full range of emotional content—positive, neutral, and negative. The data show that at least three types of infant vocalizations (squeals, vowel-like sounds, and growls) occur with this full range of expression by 3–4 mo of age. In contrast, infant cry and laughter, which are species-specific signals apparently homologous to vocal calls in other pri-mates, show functional stability, with cry overwhelmingly express-ing negative and laughter positive emotional states. Functional flexibility is a sine qua non in spoken language, because all words or sentences can be produced as expressions of varying emotional states and because learning conventional "meanings" requires the ability to produce sounds that are free of any predetermined func-tion. Functional flexibility is a defining characteristic of language, and empirically it appears before syntax, word learning, and even earlier-developing features presumed to be critical to language (e.g., joint attention, syllable imitation, and canonical babbling). The ap-pearance of functional flexibility early in the first year of human life is a critical step in the development of vocal language and may have been a critical step in the evolution of human language, preceding protosyntax and even primitive single words. Such flexible affect expression of vocalizations has not yet been reported for any non-human primate but if found to occur would suggest deep roots for functional flexibility of vocalization in our primate heritage.
Identification of Prelinguistic Phonological Categories
Journal of Speech Language and Hearing ResearchRamsdell, H.L., Oller, D.K., Buder, E.H., Ethington, C.A., Chorna, L.
2012
Purpose: The prelinguistic infant's babbling repertoire of syllables--the phonological categories that form the basis for early word learning--is noticed by caregivers who interact with infants around them. Prior research on babbling has not explored the caregiver's role in recognition of early vocal categories as foundations for word learning. In the present work, the authors begin to address this gap. Method: The authors explored vocalizations produced by 8 infants at 3 ages (8, 10, and 12 months) in studies illustrating identification of phonological categories through caregiver report, laboratory procedures simulating the caregiver's natural mode of listening, and the more traditional laboratory approach (phonetic transcription). Results: Caregivers reported small repertoires of syllables for their infants. Repertoires of similar size and phonetic content were discerned in the laboratory by judges who simulated the caregiver's natural mode of listening. However, phonetic transcription with repeated listening to infant recordings yielded repertoire sizes that vastly exceeded those reported by caregivers and naturalistic listeners. Conclusions: The results suggest that caregiver report and naturalistic listening by laboratory staff can provide a new way to explore key characteristics of early infant vocal categories, a way that may provide insight into later speech and language development.
Sentence Intelligibility Before and After Voice Treatment in Speakers With Idiopathic Parkinson's Disease
Journal of Voice: Official Journal of the Voice FoundationCannito, M.P., Suiter, D.M., Beverly, D., Chorna, L., Wolf, T., Pfeiffer, R.M.
2011
The purpose of this study was to determine whether sentence intelligibility improves in speakers with idiopathic Parkinson's disease (PD) as a result of Lee Silverman Voice Treatment (LSVT). It was hypothesized that all the speakers would improve following treatment, in association with increased vocal loudness, which was the primary target of the treatment. Prospective study of eight Speakers with PD using a single-blinded, randomized pre-post treatment design, with multiple daily assessments before and after treatment was carried out. Resultant data were corrected for regression to the mean. Randomized digital recordings of sentences produced by speakers with idiopathic PD before and after the treatment were presented to normal-hearing listeners with equalized intensity at conversational loudness in the presence of pink noise. Percentage of words understood was calculated before and after the treatment. Changes in overall vocal intensity were also analyzed. There was a statistically significant group effect from pre-to-post voice treatment; however, there was also significant interaction of treatment with speakers. Six of the speakers with PD improved significantly following voice treatment, one exhibited no change, and one exhibited a decline in sentence intelligibility post-treatment. LSVT yielded significant improvement in sentence intelligibility for most speakers in the study but was not beneficial for two of the speakers despite the fact that they increased their overall vocal loudness.
Influence of Stimulus Sentence Characteristics on Speech Intelligibility Scores in Hypokinetic Dysarthria
Journal of Medical Speech-Language PathologyBeverly, D., Cannito, M.P., Chorna, L., Wolf, T., Suiter, D.M., Bene, E.R.
2010
This study was designed to investigate the effects of signal independent sentence characteristics on speech intelligibility scores. Six adult speakers with untreated hypokinetic dysarthria were audio recorded while orally reading randomly selected sentences from the Sentence Intelligibility Test (SIT). These audio recordings were then utilized in a transcription task to obtain speech intelligibility scores. The stimulus material was further analyzed to provide information regarding certain sentence characteristics that could potentially influence speech intelligibility scores (i.e., average number of syllables per word, total number of words per sentence, total number of independent vs. dependent clauses, ratio of function words to content words, and percent predictability). Multiple regression analysis revealed that sentence length and sentence predictability had a significantly unique influence on speech intelligibility scores for these selected SIT sentences. Analysis of variance further indicated that the mean intelligibility scores for short sentences were significantly greater than for long sentences. Mean intelligibility scores for sentences with high predictability were also significantly greater than for sentences with low predictability. There was no interaction of predictability with sentence length for these sentences.
Kinematic and Acoustic Steadiness of Sustained Vowels: Typical Production Versus Simulated Dyskinesia and Dysphonia
Journal of Medical Speech-Language PathologyCannito, M.P., Chorna, L., Katz, W.F.
2010
Kinematic and acoustic time-series measurements were employed to evaluate the utility of sustained vowel formant tracks as an index of vocal tract steadiness (Gerratt, 1983). Two healthy adult speakers produced sustained vowels under normal phonation conditions and while simulating articulatory dyskinesia or dysphonia. The influence of F0 variability and abnormal voice quality on the formant tracks relative to known articulator movements was assessed by comparing acoustic data with kinematic parameters determined by electromagnetic articulography (EMA). Results suggest that formant variability was greater in the unsteady (simulated dyskinetic) condition, corresponding with increased kinematic variability in the tongue and jaw. In the breathy voice condition, F1 variability exceeded that explained by the kinematic data. During rough voice production, increased variability of F1 and F2 was consistent with increased variability seen in the articulographic measurements. Within-vowel cross-correlations among acoustic and kinematic measures also suggest that formant variability, even during simulated dysphonia, was more highly related to kinematic variability than to variability of F0. Findings generally support the validity of using formant variability measures, with reasonable precautions, to quantify vocal tract steadiness for modal and for rough phonation, but not in the case of F1 during breathy phonation or for the vowel /i/ with high-pitched voices.
Dynamic Indicators of Mother-Infant Prosodic and Illocutionary Coordination
Speech Prosody 2010-Fifth International ConferenceBuder, E.H., Warlaumont, A.S., Oller, D.K., Chorna, L.B.
2009
This report introduces tools designed to detect and quantify ways in which caregivers and infants coordinate their face-to-face communicative interactions. The tools analyze this coordination at multiple levels, linking prosodic patterns to illocutionary aspects of prelinguistic discourse. Data include fundamental voice frequency and sound pressure level parameters extracted from recorded interactions and observers" codings of vocalizations according to their perceived illocutionary forces. In this approach, we do not assume that the infants" prosodic records associate categorically with any specific mature forms of linguistic or pragmatic constructs, but propose that the dyadic use of these parameters can be seen as evidence for the development of a foundational social system between mothers and infants upon which linguistic conventions can then be built. The tools are drawn accordingly from dynamic recurrence analysis and coupled-oscillators modeling and present possibilities for objective and quantitative indices of social interaction.
