Biomedical subjects

B E Murdoch

Publications and source records attributed to B E Murdoch.

71 records · Page 4Linked to original sources

PubMedDate not supplied

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.

Adult↗

PubMedDate not supplied

Subcortical brain mechanisms in speech and language.

This paper reviews current research and contemporary theories of subcortical participation in the motor control of speech production and language processing. As a necessary precursor to the discussion of the functional roles of the basal ganglia and thalamus, the neuroanatomy of the basal ganglial-thalamocortical circuitry is described. Contemporary models of hypokinetic and hyperkinetic movement disorders based on recent neuroanatomical descriptions of the multi-segmented circuits that characterise basal ganglion anatomy are described. Reported effects of surgically induced lesions in the globus pallidus and thalamus on speech production are reviewed. In addition, contemporary models proposed to explain the possible contribution of various subcortical structures to language processing are described and discussed in the context of evidence gained from observation of the effects of circumscribed surgically induced lesions in the basal ganglia and thalamus on language function. The potential of studies based on examination of the speech/language outcomes of patients undergoing pallidotomy and thalamotomy to further inform the debate relating to the role of subcortical structures in speech motor control and language processing is highlighted.

Aged↗

PubMedDate not supplied

Long-term speech and language disorders subsequent to closed head injury in children.

The speech and language functioning of a group of 20 children (aged 8-16) who had sustained a closed head injury at least 12 months previously were assessed with the purpose of developing a comprehensive profile of the type and severity of the long-term speech/language disorders exhibited by this group. The subjects were administered a battery of speech/language assessments including an articulation/phonological assessment; oromotor assessment; overall language test and specific language skills assessments. Performance of the head-injured group was compared to that of a group of non-neurologically impaired accident victims matched for age, sex and socioeconomic status. Overall language performance scores of the head-injured group were found to be significantly lower than achieved by the control group.

Adolescent↗

PubMedDate not supplied

Aphemia associated with bilateral striato-capsular lesions subsequent to cerebral anoxia.

A case is presented of a 13-year-old right-handed male who exhibited bilateral striato-capsular lesions following an episode of cerebral anoxia and a range of clinical features typical of aphemia. The findings of a neurological assessment, neuroradiological assessment and battery of speech/language tests are described and their implications for current theories regarding the role of the basal ganglia in speech/language function discussed. The patient initially demonstrated an isolated loss of the ability to articulate words without the loss of the ability to write or comprehend spoken language. His initial mutism later resolved into a dysarthria with features similar to those seen in hypokinetic dysarthria. It was concluded that striato-capsular lesions in childhood are capable of producing temporary language disturbances and in some cases a persistent dysarthria.

Adolescent↗

PubMedDate not supplied

Performance of closed head-injured children on a naming task.

The naming abilities of a group of 20 children (aged 8-16) who had sustained a closed head injury (CHI) at least 12 months previously were assessed with the purpose of examining the long-term effect of CHI on children's naming ability. Performance of the CHI group on the Boston Naming Test was compared to that of a group of non-neurologically impaired accident victims matched for age, sex and socioeconomic status. A detailed examination of the types of naming errors exhibited by the CHI children was also carried out. Boston Naming Test scores of the CHI group were found to be significantly lower than those achieved by the control group. The error pattern demonstrated by the CHI group, however, mimicked that of the control group.

Adolescent↗

PubMedDate not supplied

Unexpected recovery of functional communication following a prolonged period of mutism post-head injury.

A case is presented of a seven-year-old female who showed an unexpected recovery of functional communication skills following a prolonged period of traumatic mutism subsequent to a severe closed head injury. The patient initially presented as comatose. A period of mutism subsequent to the coma extended for ten months. Following this protracted period of mutism the child demonstrated rapid and unexpected recovery of functional communication skills, despite the persistence of higher level language deficits. The findings of a neurological assessment, neuroradiological assessment and battery of speech/language tests are described. The present case is discussed in light of the existing literature on recovery from paediatric head trauma.

Brain Damage, Chronic↗

PubMedDate not supplied

Linguistic status following closed head injury in children: a follow-up study.

The speech and language functioning of a group of 20 children (aged 8-17) who had sustained a closed head injury at least 12 months previously was assessed with the purpose of developing a comprehensive profile of the type and severity of the long-term speech/language disorders exhibited by this group. The same group of subjects was then re-evaluated 12 months after the initial testing to monitor progress of the closed head-injured group in relation to a group of non-neurologically impaired controls. The subjects were administered a battery of speech/language assessments including articulation/phonological assessment; oromotor assessment; overall language test; and specific language skills assessments. Initial and re-test performance of the head-injured group was compared to that of a group of non-neurologically impaired accident victims matched for age, sex and socioeconomic status. Comparison within the head-injured group of test and re-test performance was also carried out. Overall language performance scores of the head-injured group were found to be consistently significantly lower than achieved by the control group at both initial and re-test stages. Performance of the head-injured group had, however, improved significantly over the 12-month period.

Adolescent↗

PubMedDate not supplied

Language abilities of mildly closed head injured (CHI) children 10 years post-injury.

The language functioning of a group of 14 children who had sustained a mild closed head injury (CHI) at least 10 years previously was assessed. The subjects were administered a battery of language assessments including an overall language test, and specific language skills assessments. Performance of the head-injured group was compared with that of a group of non-neurologically impaired accident victims matched for age, sex and educational level. Overall language performance of the experimental group did not differ significantly from the controls.

Adolescent↗

PubMedDate not supplied

Hypernasality in dysarthric speakers following severe closed head injury: a perceptual and instrumental analysis.

Hypernasality in the dysarthric speech of 20 severely closed-head-injured (CHI) subjects was investigated using both perceptual and instrumental techniques. A perceptual analysis of the speech of the CHI subjects was performed using a four-point rating scale for hypernasality. Instrumental assessment was carried out using a computerized accelerometric technique yielding a nasal coupling index. Results revealed a high incidence of perceived hypernasality (95%) in the speech of subjects in the CHI group. More than half of these subjects exhibited hypernasality of speech to a moderate to severe degree. When compared with a control group matched for age and sex the severely CHI subjects were perceived as being significantly more hypernasal. Instrumental assessment revealed that the functioning of the velopharyngeal valve in the group of CHI subjects was significantly impaired compared to the control group. The study highlighted the need to evaluate the perceptual and instrumental assessment results for the severely CHI subjects on an individual basis. The clinical implications of these findings are discussed.

Adolescent↗

PubMedDate not supplied

Abnormal patterns of speech breathing in dysarthric speakers following severe closed head injury.

The respiratory abilities of a group of 20 subjects with a speech disorder resulting from severe closed head injury (CHI) were assessed using both spirometric and kinematic techniques and compared with those of a group of 20 non-neurologically impaired controls matched for age and gender. Results of the spirometric assessment showed that the CHI subjects as a group had lower vital capacities and lower forced expiratory volumes 1 second than the controls. Kinematic assessment also showed that the CHI subjects had problems co-ordinating the action of the rib-cage and abdomen when carrying out speech tasks such as vowel prolongations, syllable repetitions and reading. Results are discussed in terms of the effects of CHI on neuromuscular function.

Abdominal Muscles↗

PubMedDate not supplied

Perceptual speech characteristics of dysarthric speakers following severe closed head injury.

The perceptual speech characteristics of a group of 20 severely closed head-injured (CHI) subjects were compared with those of a normal non-neurologically impaired control group matched for age and sex. The CHI subjects were found to be significantly less intelligible than the controls, and exhibited deficits in the prosodic, resonatory, articulatory, respiratory and phonatory aspects of speech production. The most frequently occurring deviant speech dimensions related to disturbances of prosody, resonance, articulation and respiration, with those deviant speech dimensions pertaining to phonation being less apparent in the speech of the CHI subjects. The findings are discussed in relation to the heterogeneity of the CHI population and the effects of CHI on neuromuscular function. The study highlights the need for accurate, instrumental physiological evaluation of the motor subsystems involved in speech production.

Adolescent↗

PubMedDate not supplied

Severe closed-head injury in childhood: linguistic outcomes into adulthood.

The language functioning of a group of adults who had sustained a severe closed-head injury in childhood was evaluated. The subjects were administered a battery of language assessments including measures of syntax, semantics and pragmatics, as well as a measure of metalinguistic ability. Performance of the experimental group was compared with that of a control group matched for age, sex and educational level. Results indicated that all areas of language competence assessed (syntax, semantics, pragmatics) appeared to be compromised by the childhood closed-head injury.

Adolescent↗

PubMedDate not supplied

Laryngeal dysfunction in dysarthric speakers following severe closed-head injury.

The laryngeal function of 19 severely closed head-injured subjects with a perceptible dysarthria was assessed using electrolaryngography and a computerized airflow/air pressure analysis system (Aerophone II). Variables measured included parameters of the Lx waveform (Fo, duty cycle and closing time) as well as aerodynamic parameters such as subglottal pressure, glottal resistance, average phonatory sound pressure level, phonatory flow rate and ad/abduction rate. Values were compared to those recorded from a non-neurologically impaired control group matched for age and sex, and correlated with the findings of a perceptual speech analysis. The findings are discussed in relation to the effects of a severe closed-head injury on laryngeal function. The clinical implications of the findings for the assessment and treatment of vocal dysfunction in head-injured subjects are also discussed.

Dysarthria↗

PubMedDate not supplied

Acute lymphoblastic leukaemia: language deficits in children post-treatment.

The language abilities of a group of 22 children (aged between 5 years and 17 years, 9 months) treated for acute lymphoblastic leukaemia (ALL) were investigated and compared with those of a group of non-neurologically impaired, age- and sex-matched controls. The language test battery included an age-appropriate measure from the Test of Language Development (TOLD) series, consisting of either the Test of Adolescent Language (TOAL--2), or the Test of Language Development--Intermediate or --Primary (TOLD--I or --P); the timed subtests of the Clinical Evaluation of Language Function (CELF); the Boston Naming Test; and one of either the Token Test or the Token Test for Children, depending on the age of the subject. As a group, the leukaemia subjects performed significantly worse than the controls on the TOAL--2, TOLD--I, TOLD--P, Token Test, and Boston Naming Test. The need for post-treatment monitoring of the language abilities of children treated for ALL to enable early remediation of areas of deficit is highlighted.

Adolescent↗

PubMedDate not supplied

Physiological and perceptual features of dysarthria in Moebius syndrome: directions for treatment.

The functioning of the major subsystems of the speech production apparatus of a 12 year old female with Moebius syndrome was investigated using a battery of perceptual and physiological instrumental measures. Perceptual tests administered included: The Assessment of Intelligibility of Dysarthric Speech; the Frenchay Dysarthria Assessment; and a perceptual analysis of a speech sample based on a reading of the Grandfather Passage. Instrumental procedures included: spirometric and kinematic analysis of speech breathing; electroglottographic and aerodynamic evaluation of laryngeal function; nasometric assessment of velopharyngeal function; and evaluation of lip and tongue function using a variety of strain-gauge and pressure transducers. Consistent with the pathophysiological basis of Moebius syndrome, the major dysfunctions of the speech production mechanism were found at the level of the articulatory valve. Somewhat unexpectedly, however, impaired function was also identified at the level of the velopharyngeal and laryngeal valves by both the perceptual and instrumental assessments and at the level of the respiratory system by the physiological analysis alone. The results are discussed with reference to the neurological basis and clinical features of Moebius syndrome. The implications of the findings for the treatment of congenital dysarthria associated with Moebius syndrome are also discussed. The advantage of instrumental analysis over perceptual assessments in defining treatment goals for children with congenital dysarthria is highlighted.

Child↗

PubMedDate not supplied

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 subject's 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 child's 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.

Basilar Artery↗

PubMedDate not supplied

Motor speech impairment following traumatic brain injury in childhood: a physiological and perceptual analysis of one case.

The physiological and perceptual characteristics of persistent dysarthria exhibited by a 14 year-old boy, following a severe traumatic brain injury (TBI) were investigated. The subject's speech and motor speech mechanism were comprehensively evaluated both perceptually and physiologically, and the findings were compared with those of a non-neurologically impaired control subject, matched for age and sex, and a number of control groups from previous studies. Overall, the assessments indicated that the major motor speech deficits demonstrated by the subject included severely reduced tongue function, and moderately impaired lip, laryngeal, and velopharyngeal function. Respiratory function was found to be mildly impaired. Perceptual assessments indicated that the subject's speech was severely impaired in relation to rate, pitch variation, and consonant precision, with a moderate impairment in overall intelligibility. The effects of a severe TBI on the functioning of the child's motor speech mechanism were discussed. The clinical implications for the assessment and treatment of dysarthria in childhood following severe TBI were highlighted.

Adolescent↗