Dysarthria

About: Dysarthria is a research topic. Over the lifetime, 2402 publications have been published within this topic receiving 56554 citations.

Quantitative Assessment of Syllabic Timing Deficits in Ataxic Dysarthria

Abstract: Parametric analysis of Cerebellar Dysarthria (CD) may be valuable and more informative compared to its clinical assessment. A quantifiable estimation of the timing deficits in repeated syllabic utterance is described in the current study. Thirty-five individuals were diagnosed with cerebellar ataxia to varying degrees and twenty-six age-matched healthy controls were recruited. To automatically detect the local maxima of each syllable in the recorded speech files, a topographic prominence incorporated concept is designed. Subsequently, four acoustic features and eight corresponding parametric measurements are extracted to identify articulatory deficits in ataxic dysarthria. A comparative study on the behaviour of these measures for dysarthric and non-dysarthric subjects is presented in this paper. The results are further explored using a dimensionreduction tool (Principal Component Analysis) to emphasize variation and bring out the strongest discriminating patterns in our feature dataset.

Perspectives on the Psychosocial Management of Oromandibular Dystonia.

Abstract: Oromandibular dystonia (OMD) is a rare disorder of movement characterized by tonic muscle contractions that can result in involuntary, repetitive, and patterned muscle contractions of the lingual musculature, labial musculature, and/or muscles of mastication. As a result, dysarthria can be present that can lead to reduced speech intelligibility and have an adverse impact on psychosocial functioning. In this article, we will describe the clinical and speech characteristics of OMD and the various methods of treatment. Then we will introduce and describe patient-reported outcome measures that assess two aspects of psychosocial functioning: communicative participation and quality of life. We will describe the current state of knowledge as it relates to communicative participation and quality of life in this clinical population, and, finally, we will advocate that speech-language pathologists have a unique role in the care of individuals with OMD through the inclusion of patient-reported outcome measures to provide a comprehensive and holistic management plan.

Nonlanguage disorders of speech reflect complex neurologic apparatus.

Abstract: The mute or nearly mute patient who is alert and has good understanding of speech and a right hemiparesis could have Broca's aphasia, akinesia of speech (transcortical motor aphasia), or aphemia. The patient who has Broca's aphasia does not write well, and his speech does not improve greatly with repetition. The speech of a patient with akinesia of speech improves with repetition. The aphemic patient writes normally, but his speech does not improve with repetition. The mute patient whose eyes are open but who is poorly responsive and moves little or not at all could be an akinetic mute (with either a cingulate or a thalamomesencephalic lesion) or have a locked-in syndrome. The latter is diagnosed by asking the patient to look up and down or to open and close his eyes. If he obeys these commands, the physician questions him using a code of eye movement responses. If the patient fails to respond at all, he is an akinetic mute; intense stimulation may result in speech or movement. If the patient is drowsy and has third nerve involvement, the lesion is in the thalamomesencephalic reticular formation. If the patient appears alert and has episodes of agitation, he probably has bilateral lesions in the gyri cinguli. Patients with weakness of the bulbar musculature (facial, palatal, and tongue weakness and dysphonia) may have either upper motor neuron or lower motor neuron lesions. Only bilateral upper motor neuron lesions produce permanent dysarthria. As a typical example, a patient has a transient left hemiparesis with dysarthria and almost completely recovers. Later, however, a right hemiparesis develops and the patient experiences severe bilateral facial weakness, drooling, dysphagia, and severe dysarthria. The absence of atrophy of the bulbar musculature, a hyperactive jaw jerk and gag reflex and, sometimes, inappropriate laughing or crying episodes indicate that the lesion is located above the medulla in the corticobulbar tracts. Flaccid paralysis, absence of the jaw jerk or gag reflex, and absence of other upper motor neuron signs, such as upgoing toes, indicate a lower motor neuron or neuromuscular junction problem. Appropriate tests to rule out myasthenia gravis should be done. The other conditions discussed here are often obvious from their clinical presentation. Although the specific disorder of speech sometimes is helpful in localizing the cause, in most patients, the associated deficits on neurologic examination are of greatest value.

Reduced Breath Support in a Speaker with Dysarthria Secondary to Multiple Sclerosis: Its Impact on Conversational Speech

Abstract: This case study describes a patient with reduced breath support due to multiple sclerosis. Although deficits to the supralaryngeal structures are more commonly associated with a reduction in intelligibility, atypical breathing patterns can severely impact the perceptual coherence of dysarthric speech. This is most likely to manifest in conversational speech as the demands of correctly signalling syntactic, pragmatic and interactional information all rely on control of the breath support system. The study uses the method of interactional phonetics to consider in combination the role of phonetic, linguistic and interactional design in the speaker's natural conversation. The analysis was carried out by taking into account the sequential order of turns and representative extracts are presented. The patient's dysarthria has previously been identified as mild but the findings indicate that issues surrounding breath group length, speech rate and phonatory instability all surface in conversational speech. Of particular interest are the introduction of new person referents and their potential to trigger repair sequences. The findings indicate that a mild dysarthria with reduced breath support as a primary symptom can cause considerable problems of understandability in conversational speech. However, attention to the way in which potentially problematic interactional tasks are carried out and the successful use of repair strategies can minimize these issues.KEYWORDS: dysarthria; multiple sclerosis; phonetics.(ProQuest: ... denotes formulae omitted.)1. Introduction1.1. Breath support in dysarthriaMultiple sclerosis (MS) is an acquired disease of the central nervous system causing destruction of myelin sheath (a process known as demyelination). If demyelination occurs in the cranial nerves responsible for the innervation of the speech structures, some form of dysarthria is likely to present. The dysarthrias of MS have the potential to affect all subsystems of speech and Theodoros et al. (2000) identify articulatory imprecision, a harsh voice quality, impaired stress patterns (sometimes referred to as 'scanning speech'), a reduction in breath support, and reduced pitch variation as the primary speech characteristics. Dysphonia and phonatory instability have also been reported as being particularly prevalent (Hartelius et al. 1997; Feijo et al. 2004).Dysarthria is a principal example of a communication impairment where intelligibility can be compromised (Duffy 2005). Depending on the type and severity of the symptoms, varying degrees of disturbance to a patient's ability to convey linguistic meaning can occur. While a marked reduction in intelligibility is most typically associated with muscle control of the supralaryngeal vocal tract, problems with the respiratory system can also cause difficulties. Of concern in this paper is the phenomenon of reduced breath support and its manifestations in conversation. Reduced breath support is often associated with vagus nerve lesions and symptoms include reduced breath group length, increased pause frequency and duration, and loss of phonation (Yorkston et al. 1988). There is also the possibility of interaction between respiratory and phonatory instability.The impact of reduced breath support on speech is highly dependent on the type of task being carried out. Bellaire et al. (1986) observe that while a decreased number of words per breath group may not reduce intelligibility per se it is likely to lead to a reduction in the perception of speech 'naturalness'. Similarly, Heselwood's study of hypovalving (2007) indicates that frequent breath pauses can lead to a perception of dysfluency. However, there is also the potential for respiratory/phonatory inadequacy to lead to problems conveying linguistic meaning. Hoit et al. (1993) demonstrate that decreased lung volume can affect voice onset time and therefore the signalling of certain lexical contrasts. …

Estimation of Phoneme-Specific HMM Topologies for the Automatic Recognition of Dysarthric Speech

Abstract: Dysarthria is a frequently occurring motor speech disorder which can be caused by neurological trauma, cerebral palsy, or degenerative neurological diseases. Because dysarthria affects phonation, articulation, and prosody, spoken communication of dysarthric speakers gets seriously restricted, affecting their quality of life and confidence. Assistive technology has led to the development of speech applications to improve the spoken communication of dysarthric speakers. In this field, this paper presents an approach to improve the accuracy of HMM-based speech recognition systems. Because phonatory dysfunction is a main characteristic of dysarthric speech, the phonemes of a dysarthric speaker are affected at different levels. Thus, the approach consists in finding the most suitable type of HMM topology (Bakis, Ergodic) for each phoneme in the speaker's phonetic repertoire. The topology is further refined with a suitable number of states and Gaussian mixture components for acoustic modelling. This represents a difference when compared with studies where a single topology is assumed for all phonemes. Finding the suitable parameters (topology and mixtures components) is performed with a Genetic Algorithm (GA). Experiments with a well-known dysarthric speech database showed statistically significant improvements of the proposed approach when compared with the single topology approach, even for speakers with severe dysarthria.