Elizabeth C. Thompson

The effects of age and gender on laryngeal aerodynamics

A computerized airflow/air pressure analysis system, the Aerophone II Model 6800 (Kay Elemetrics Corp.), was used to assess the effects of age and gender on laryngeal aerodynamics. A sample of 56 male and 53 female normal speaking subjects was divided into six age groups (20-30; 31-40; 41-50; 51-60; 61-70 and 71-80 years). The laryngeal aerodynamic parameters measured included phonatory (mean) flow rate, estimated subglottal pressure, laryngeal airway resistance, phonatory sound pressure level, phonatory power, and phonatory efficiency. Most comfortable phonation, vocal efficiency, and running speech tasks were used to collect the aerodynamic data. Comfortable pitch and loudness levels were used for each of these tasks. Age and gender effects were found for a number of the phonatory (mean) flow rate and phonatory sound pressure level values. Results failed, however, to indicate age or gender effects for the estimated subglottal pressure, laryngeal airway resistance, phonatory power and phonatory efficiency parameters. High intersubject variability was found for the phonatory flow rate, laryngeal airway resistance, phonatory power and phonatory efficiency values. Estimated subglottal pressure values, however, appeared to vary the least among subjects. The results are discussed with respect to factors that might influence laryngeal aerodynamics, such as underlying laryngeal anatomical and physiological age-related changes and gender-related differences. The clinical implications of the findings for the assessment and treatment of individuals with voice disorders using the Aerophone II are also discussed.

Lip function in subjects with upper motor neuron type dysarthria following cerebrovascular accidents

The lip function of 16 speakers with upper motor neuron damage following cerebrovascular accident (CVA), was investigated using instrumental measures. Sixteen, non-neurologically impaired adults matched for age and sex served as controls. The results of the instrumental investigations revealed that the CVA speakers had patterns of lip function that were significantly different from the control speakers. Specifically, on maximum force tasks, the CVA speakers were found to produce significantly lower maximum lip force values. Maximum rate of attempts at lip movement was also slower in the CVA speakers. In addition, the instrumental investigation revealed that the CVA speakers demonstrated a significant decline in pressure over the course of the task involving 10 attempts at maximum lip force. In contrast, the control speakers maintained a consistent level of force throughout the 10 repetitions/attempts. Overall, the findings suggest that the CVA speakers have deficits in maximum lip force, endurance of lip strength and rate of lip movements. Correlations conducted between instrumental measures of maximum lip strength and the perceptual ratings of overall intelligibility, precision of consonants, precision of vowels and length of phonemes revealed no significant relationship.

Variability in upper motor neurone-type dysarthria: an examination of five cases with dysarthria following cerebrovascular accident

The degree of diversity in the nature and extent of the physiological deficits which occur in subjects with dysarthria with similar neurological damage is demonstrated through the individual assessment profiles of five subjects with dysarthria following upper motor neurone (UMN) damage. The perceptual profiles of each subject were compiled using perceptual ratings of deviant speech parameters, intelligibility ratings from the Assessment of Intelligibility of Dysarthric Speech (ASSIDS), and perceptual judgements of subsystem function determined from the Frenchay Dysarthria Assessment (FDA). For each individual, the perceptual profile of their speech impairments was compared and contrasted with the objective results of spirometric and kinematic assessments of respiratory function aerodynamic and electroglottographic evaluations of laryngeal function, pressure and strain gauge evaluations of articulatory function, and nasal accelerometric assessments of nasality. The outcomes of the individual perceptual and physiological profiles are discussed with respect to the presence of differential subsystem impairments both within each subject and between subjects with similar underlying pathophysiological deficits. The importance of interpreting the instrumental findings with respect to the interdependency of each of the motor speech subsystems, the limitations of perceptual assessments, and the advantages of utilising both perceptual and physiological analyses in the process of identifying treatment goals is discussed.

Laryngeal and phonatory dysfunction in Parkinson's disease

The vocal function of 20 speech-disordered subjects with idiopathic Parkinsons disease (PD) was assessed using both perceptual and instrumental techniques. The instrumental analysis included electroglottography and the use of a computerized airflow/air pressure analysis system (Aerophone II). Variables measured included parameters of the Lx waveform (F0, duty cycle, and closing time) as well as aerodynamic parameters such as subglottal pressure, laryngeal airway resistance, average phonatory sound pressure level, phonatory flow rate and ad/abduction rate. Values were compared to those recorded from a group of non-neurologically impaired controls matched for age and sex. Perceptual assessment revealed that 89·5% of the PD subjects exhibited deviant laryngeal features. None of the electroglottography (EGG) parameters differed significantly between the PD and control groups. However four of the five aerophone parameters did differentiate between the two subject groups. The PD group was characterized by high...

Motor speech impairment in a case of childhood basilar artery stroke: Treatment directions derived from physiological and perceptual assessment

The perceptual and physiological characteristics of the speech of a nine year old child who suffered a basilar artery stroke at the age of five years were investigated using a battery of perceptual and physiological instrumental measures. Perceptual tests administered included the Frenchay Dysarthria Assessment, a perceptual analysis of a speech sample based on a reading of the Grandfather Passage and a phonetic intelligibility test. Instrumental procedures included: spirometric and kinematic analysis of speech breathing; electroglottographic evaluation of laryngeal function, nasometric assessment of velopharyngeal function and evaluation of lip and tongue function using pressure transducers. Physiological assessment indicated the most severe deficits to be in the respiratory and velopharyngeal sub-systems with significant deficits in the articulatory sub-system, all of which resulted in severely reduced intelligibility. These results were compared and contrasted with the subjects performance on the perceptual assessment battery. In a number of instances the physiological assessments were able to identify deficits in the functioning of components of the speech production apparatus either not evidenced by the perceptual assessments or where the findings of the various perceptual assessments were contradictory. The resulting comprehensive profile of the childs dysarthria demonstrated the value of using an assessment battery comprised of both physiological and perceptual methods. In particular, the need to include instrumental analysis of the functioning of the various subcomponents of the speech production apparatus in the assessment battery when defining the treatment priorities for children with acquired dysarthria is highlighted. Treatment priorities determined on the basis of both the perceptual and physiological assessments for the present CVA case are discussed.

Lip and tongue function in children with developmental speech disorders: A preliminary investigation

Four children with developmental verbal dyspraxia (DVD), and three children with inconsistent deviant phonological disorder were compared to age-matched control children on measures of tongue strength and endurance and lip movement. The instrument for measuring tongue strength was composed of an air-filled soft rubber bulb connected to a pressure transducer. Measurements of lip movement during speech and non-speech tasks were taken from a video-recording of the childs mouth, recorded using a Perspex grid overlay. The results indicated that the DVD subjects were poorer than the control children on all measures of tongue strength and endurance. While the inconsistent deviant children performed similarly to age-matched controls on the maximum tongue strength task, their performance on endurance and repetitive tasks fell between that of the DVD and control groups. The preliminary lip movement analysis suggested some deficit in control of lip movement for the DVD and inconsistent subjects. Overall the findings support the hypothesis that children with DVD and those with inconsistent deviant phonology have some form of motor impairment. The differential performance of the two subject groups on tongue strength and endurance tasks is in accordance with the hypothesis that DVD and inconsistent deviant phonology are distinct subgroups of developmental speech disorders. The need for further physiological investigation of the oro-motor skills of speech-impaired children is discussed.

Disorders of nasality in subjects with upper motor neuron type dysarthria following cerebrovascular accident

The nasality of 19 subjects with upper motor neuron (UMN) damage following cerebrovascular accident (CVA), and 19 control subjects matched for age and sex, was investigated using both perceptual judgements of nasality and a modified version of the nasal accelerometric procedure described by Horii (1980). Nasality indices were calculated for each subject during the production of a series of nasal and non-nasal sounds, words, and sentences. Statistical comparison of the two groups revealed that the CVA subjects had significantly higher nasality indices on the production of nonnasal speech tasks than the controls. No significant difference was noted between the two groups on nasal tasks. Individual case by case examination of the accelerometer data confirmed the presence of hypernasality in 7 of the 19 CVA subjects. In contrast to the instrumental findings, the results of the perceptual judgements of nasality identified the presence of hypernasality, hyponasality, and normal nasal resonance within the CVA group.