Richard D. Andreatta

Two-Week Joint Mobilization Intervention Improves Self-Reported Function, Range of Motion, and Dynamic Balance in Those with Chronic Ankle Instability

We examined the effect of a 2‐week anterior‐to‐posterior ankle joint mobilization intervention on weight‐bearing dorsiflexion range of motion (ROM), dynamic balance, and self‐reported function in subjects with chronic ankle instability (CAI). In this prospective cohort study, subjects received six Maitland Grade III anterior‐to‐posterior joint mobilization treatments over 2 weeks. Weight‐bearing dorsiflexion ROM, the anterior, posteromedial, and posterolateral reach directions of the Star Excursion Balance Test (SEBT), and self‐reported function on the Foot and Ankle Ability Measure (FAAM) were assessed 1 week before the intervention (baseline), prior to the first treatment (pre‐intervention), 24–48 h following the final treatment (post‐intervention), and 1 week later (1‐week follow‐up) in 12 adults (6 males and 6 females) with CAI. The results indicate that dorsiflexion ROM, reach distance in all directions of the SEBT, and the FAAM improved (p < 0.05 for all) in all measures following the intervention compared to those prior to the intervention. No differences were observed in any assessments between the baseline and pre‐intervention measures or between the post‐intervention and 1‐week follow‐up measures (p > 0.05). These results indicate that the joint mobilization intervention that targeted posterior talar glide was able to improve measures of function in adults with CAI for at least 1 week.

Transitional properties of the mechanically evoked perioral reflex from infancy through adulthood

The organization of motor responses in the orbicularis oris muscle following the delivery of punctate mechanical inputs to vermilion skin of the lips was studied in a group of young infants, school-age children, and adults during periods of voluntary lip muscle activation. A specially designed multi-point array skin contactor, coupled to a position-servo controlled linear motor, was highly effective in driving the early component of the perioral reflex (R1). Overall, the evoked R1 response obtained from the infant was of variable amplitude relative to the children and adults, lacked response specificity, and occurred at a longer latency. This brainstem mediated sensorimotor action appears to take on several characteristics of the adult form by the age of 12. The emergence and maturation of mechanically evoked perioral reflexes is discussed in relation to the acquisition of motor skills, including speech and smiling.

Plantar vibrotactile detection deficits in adults with chronic ankle instability.

PURPOSE The purpose of this study was to investigate the vibrotactile detection thresholds of the plantar cutaneous afferents in subjects with chronic ankle instability compared with healthy control subjects. METHODS Eight adults with chronic ankle instability and eight adults with no ankle sprain history participated. Vibrotactile detection thresholds were assessed using a mechanical stimulus generator system, mounted onto an articulated microscope arm, which delivered sinusoidal vibrotactile inputs to the foot sole at three different sites: head of the first metatarsal, base of the fifth metatarsal, and the heel. Vibrotactile stimulation was delivered at a range of test frequencies that corresponded to the known responsiveness of cutaneous mechanoreceptors in the glabrous skin of the foot sole (10, 25, and 50 Hz). Probe displacement measures (dB) from the last eight displacement trials that contained 50% positive detection responses were averaged to obtain a single threshold estimate for each test frequency and site combination. RESULTS The results of this study indicate that no significant group-by-site interactions were found for any test frequencies (P > 0.29). However, group main effects were present at the 10-Hz (P < 0.0001), 25-Hz (P = 0.03), and 50-Hz (P = 0.04) test frequencies, indicating that subjects with chronic ankle instability had significantly higher detection thresholds or less sensitivity when stimulation sites were pooled. CONCLUSIONS The results of this study indicate that subjects with chronic ankle instability may demonstrate decreased sensitivity on the plantar surface of the foot. These alterations in plantar cutaneous somatosensation may help explain the underlying mechanisms associated with the prolonged sensorimotor system impairments in postural control and gait commonly exhibited by people with chronic ankle instability.

Modulation of the mechanically evoked perioral reflex during active force dynamics in young adults

Mechanically evoked reflex activity in the superior and inferior segments of the orbicularis oris muscle was sampled from three normal females using a specially designed linear motor operating under force feedback. Mechanical inputs delivered to the left upper lip during a ramp-and-hold task produced a composite reflex response characterized by phases of excitation and suppression at the homonymous muscle recording site. The modulation of the evoked composite perioral reflex was found to be dependent upon the rate and phase of force recruitment. The organization of the composite perioral reflex response is discussed in relation to speech motor control and load compensatory mechanisms.

Preliminary findings on the relation between the personality trait of stress reaction and the central neural control of human vocalization.

Abstract The objectives of this study were to examine whether the personality trait of stress reaction (SR), as assessed with the Multidimensional Personality Questionnaire-Brief Form (MPQ-BF), (1) influences prefrontal and limbic area activity during overt sentence reading and if (2) SR and associated individual differences in prefrontal and limbic activations correlate with sensorimotor cortical activity during overt sentence reading. Ten vocally healthy adults (22–57 years) participated in a functional MRI study using an event-related sparse sampling design to acquire brain activation data during sentence production tasks (covert, whispered, overt). The outcome measure was the blood oxygenation level-dependent signal change in prefrontal, limbic, and primary somatosensory (S1) and motor cortices (M1). Significant positive correlations were found between SR scores and S1, dorsolateral prefrontal cortex (both r =.73, p <.05), and periaqueductal gray (r =.88, p <.01) activity. M1 activity was positively correlated with SR (r =.64, p <.05) and negatively with social potency (r = −.70, p <.05). Our findings suggest that motor cortical control subserving voice and speech production varies with expression of selected personality traits. Future studies should investigate the functional significance of personality differences in the central neural control of vocalization.

Immediate Effects of the Vocal Function Exercises Semi-Occluded Mouth Posture on Glottal Airflow Parameters: A Preliminary Study

OBJECTIVES The study aimed to quantify immediate alterations in the airflow glottogram between the Vocal Function Exercises semi-occluded mouth posture (/ol/ with lip buzz) and the sustained vowel /o/ in individuals with normal voices, and to determine if noted changes were in agreement with established semi-occluded vocal tract aerodynamic theory. Based on semi-occluded vocal tract aerodynamic theory, we hypothesized the following immediate changes in the flow glottogram during the /ol-buzz/ condition: a greater open quotient, a greater skewing quotient, a greater maximum flow declination rate, increased average airflow, decreased peak airflow, and increased minimum airflow. METHODS A cohort of eight men with normal voices produced the sustained vowel /o/ and the Vocal Function Exercises semi-occluded mouth posture (/ol-buzz/). Flow glottograms for both conditions were obtained from the inverse-filtered oral airflow signal via a circumferentially vented pneumotachograph mask. RESULTS Data revealed that open quotient and minimum airflow rates increased significantly between conditions. All other measures trended in the directions predicted by aerodynamic theory, but were not statistically significant. CONCLUSIONS The Vocal Function Exercises semi-occluded mouth posture appeared to provide an effective vocal tract semi-occlusion that immediately altered the flow glottogram in accordance with predictions made by computer-modeled aerodynamic theory.

Quantitative and qualitative research paradigms: Thoughts on the quantity and the creativity of stuttering research

Analysis of publication patterns in stuttering research showed that over 90% of articles published in three major journals between 1994 and 2003 could be described as representing a quantitative, as opposed to qualitative, tradition. Many other authors have already discussed two possible implications of this imbalance: that quantitative research is overrepresented, and that qualitative research needs to be more frequently used in stuttering. This article was constructed, therefore, to address three other possible implications of publication patterns in stuttering research: under-reporting of qualitative methodologies; under-adoption of new knowledge; and under-use of creative, interdisciplinary quantitative methodologies.

Induced unilateral vocal fold paralysis and recovery rapidly modulate brain areas related to phonatory behavior: a case study.

BACKGROUND Peripheral and behavioral effects of voice disorders are well documented in the literature; yet, there is little information regarding the central neural biomarkers and mechanisms underlying these disorders. Understanding the details of brain function changes in disordered voice production is a critical factor for developing better treatment strategies that result in more robust patient outcomes. OBJECTIVE To examine a model of induced unilateral vocal fold paralysis (iUVFP) to demonstrate and characterize the form of activity changes within central mappings of the larynx to the induced paralysis. The induced paralysis model allowed the participant to serve as his or her own control when comparing baseline results of normal voice with results during the paralysis and subsequent recovery. STUDY DESIGN Prospective, case-study design. METHODS Functional magnetic resonance imaging was used to examine central laryngeal representations during three time points: pre-iUVFP, during iUVFP, and postrecovery from iUVFP. iUVFP was induced using a lidocaine with epinephrine nerve block unilaterally. Percent changes in blood oxygenation level-dependent (BOLD) activity served as the dependent variable. RESULTS Results indicated an overall reduced activity level in sensorimotor, subcortical, and cerebellar regions during paralysis. Recovery from paralysis led to augmented responses, particularly in sensory, association, and cerebellar zones. CONCLUSIONS The decrease in activity during iUVFP and the significantly increased activity during the recovery phase likely represent immediate neuroplastic events occurring within minutes of nerve blockade. Recovery-related changes in the BOLD response are hypothesized to be associated with a recalibration of the system after return of normal laryngeal function.

Vocal Function Exercises for Normal Voice: The Effects of Varying Dosage

Abstract Purpose: This study examined the effect of varying dosage of vocal function exercise (VFE) home practice on attainment of pre-established maximum phonation time (MPT) goals in individuals with normal voice. High dosage VFE practice was expected to result in greatest MPT. The overarching goal of this study was to contribute to a VFE dosage-response curve, potentially including a point of observable toxicity. Method: Twenty-eight females ages 18–25 with normal voice participated in this pre-post longitudinal group study. Participants were randomly assigned to one of three experimental groups and completed a six-week VFE protocol with practice twice daily. The low dosage group performed each exercise once, the traditional group twice, and the high dosage group four times. The primary outcome measure was MPT as performed on the fourth VFE using the prescribed semi-occluded vocal tract posture. Result: No toxic effects were observed. MPT increased for all participants, with significant improvement for traditional and high dosage groups. Conclusion: High dosage VFEs may yield more rapid improvement in MPT, however benefits must be weighed against the risk of increased attrition. Low dosage VFEs insufficiently improved MPT. Further research on dosage is warranted, and should include individuals with disordered voice.

The relationship between labial vibrotactile detection and pure-tone hearing thresholds in healthy, ageing adults

Purpose: Orofacial anatomy is unique from other body systems in that oral musculature inserts directly into the underlying cutaneous skin, allowing for tight temporal synchronicity between somatosensory and auditory performance feedback to maintain correct orofacial behaviours across the lifespan. Unfortunately, little is currently known regarding the changes in orofacial sensory capacities associated with ageing and how these somatosensory and auditory changes may impact feedback during functional behaviours such as speech or swallowing. The purpose of this descriptive study was to begin assessing the relationship between the auditory and labial somatosensory system in healthy ageing adults. Method: Pure-tone hearing thresholds were determined for 500, 1000, 2000 and 4000 Hz. Using a 2-alternative forced choice paradigm, 60 adults (19–84 years) completed vibrotactile detection thresholds (VDT) at the 5 and 10 Hz test frequencies. Result: A significant difference for age by group was identified at the 5 Hz test frequency. Spearman Correlations identified a significant correlation between age and pure tone hearing thresholds and the 5 Hz test frequency threshold. Conclusion: A relationship between pure tone hearing thresholds and labial somatosensory was identified. Future studies will begin the processing of modelling the complex multivariate sensorimotor relationship in healthy individuals before moving to a disordered population.