published_or_final_version / Psychology / Master / Master of Philosophy

M.A. / Parkinson's disease is a progressive neurological disorder. Symptoms such as tremor, muscular stiffness and slowness of bodily movement are prevalent in the disease. Early research studies have investigated emotional difficulties experienced by Parkinson's disease patients. Most research studies have focused on depression in Parkinson's disease. However few studies have investigated other emotional concomitants of Parkinson's disease, for example anxiety, self-esteem and impulse control. The aim of the present study was to investigate emotional concomitants of Parkinson's disease and to explore problematic emotional symptoms experienced by patients suffering from Parkinson's disease. The aim of the study was to compare a group of 10 male Parkinson's disease patients with a group of 10 healthy males (non-Parkinson's disease males) regarding the six subscales (Thought/Behaviour disorder, Impulse Control, Anxiety, Depression, Low Self-esteem and Total Pathology) of the Emotional Problems Scales (EPS). In the second part of the present study a group of six male Parkinson's disease patients completed the Millon Clinical Multiaxial Inventory (MCMI). The Millon Clinical Multiaxial Inventory consists of 22 clinical scales. The results indicated that there were statistically significant differences between the Parkinson's disease patients and the non-Parkinson's disease males regarding the Anxiety, Depression and Total Pathology subscales of the Emotional Problems Scales. The results further indicated that the Parkinson's disease patients had elevated scores above the 75 and 85 base rate scores of the Millon Clinical Multiaxial Inventory. The elevated scores were on the Schizoid, Compulsive, Self-defeating, Anxiety and Dysthymia scales. The results obtained in the present research study support previous studies regarding emotional concomitants in Parkinson's disease. Although effort has been made to ensure the present research study is methodologically sound, the study had a few shortfalls and limitations. The questionnaires (EPS and MCMI) used in the present study have not been standardised for the South African population. The present research study was interesting but a larger sample would be needed that would be more representative of the South African population. The present study did not discriminate between tremor dominant Parkinson's disease and rigid Parkinson's disease. Incidence of depression seems to be higher in Parkinson's disease patients with prominent features of bradykinesia and gait instability. It is recommended that future research studies distinguish between rigid Parkinson's disease and tremor dominant Parkinson's disease. Future research should also include measuring instruments that have been standardised for the South African population. Combined gender studies regarding emotional concomitants of Parkinson's disease will contribute to understanding the problematic emotional symptoms experienced by patients suffering from Parkinson's disease.

Several tasks examined implicit and explicit memory in matched samples of Alzheimer's (AD) and Parkinson's disease (PD) patients, and healthy elderly subjects. Lexical priming, pursuit-rotor tracking, and a fragmented pictures test, followed by explicit memory tests, were given. AD patients were impaired on all explicit tests and on lexical priming, but were intact on pursuit-rotor tracking and the procedural learning (PL) component of the fragmented pictures test. PD patients were significantly better than AD patients on all explicit memory tests, but were selectively impaired on the PL component of the fragmented pictures test. Finally, a mirror reading test was given to the PD patients and matched control subjects, with no significant differences in performance between the two groups demonstrated. Results are discussed in terms of hypothetical cognitive processes and brain circuits underlying different explicit and implicit memory domains.

Hypokinetic dysarthria is a speech disorder that commonly occurs in individuals with Parkinson’s disease (PD). However, little is known about the speech characteristics and the effects of speech treatment on the speech of Mandarin speakers with hypokinetic dysarthria (henceforth, Mandarin speakers with PD). The purpose of this dissertation was to investigate the effects of intensive voice treatment on the speech intelligibility and acoustics of this population. This dissertation consisted of three papers. The first paper, “Acoustic and perceptual speech characteristics of native Mandarin speakers with Parkinson’s disease,” investigated the general speech characteristics of 11 Mandarin speakers with PD. Intelligibility and acoustic outcomes were reported and compared to seven age- and gender-matched neurologically healthy controls. Findings from this study showed that Mandarin speakers with PD exhibited decreased intelligibility, local pitch variation, vowel space area, speech rate, and rate variation. The second paper, “Effects of Loudness and Rate Manipulation Strategies on Speech Intelligibility and Acoustics of Mandarin Speakers With Parkinson’s Disease,” examined the effects of cueing to increase loudness and reduce speech rate on speech intelligibility and acoustics. Acoustic features including speech intensity, pitch range, pause duration, pause frequency, articulation rate, and vowel space area across 11 Mandarin speakers with PD were analyzed. The relationship between speech intelligibility and acoustic features was reported. Results showed that cueing for loud speech significantly increased intelligibility, but cueing for slow speech did not. Different cues had differential effects on the selected acoustic features. Cueing for loud speech resulted in increased vocal intensity and cueing for slow speech resulted in reduced articulation rate and increased pause frequency. In the loud speaking condition, greater vocal intensity and larger vowel space contributed to increased intelligibility, whereas in the slow condition, increased intensity, vowel space, as well as articulation rate, showed a trend toward contributing to increased intelligibility. The third paper, “The Effects of Intensive Voice Treatment on Intelligibility in Mandarin Speakers with Parkinson’s Disease: Acoustic and perceptual findings,” investigated the short- and long-term effects of intensive voice treatment (Lee Silverman Voice Treatment LOUD) on speech intelligibility and acoustics of nine Mandarin speakers with PD. All speakers showed increased intelligibility from pretreatment to immediate post-treatment, and the improvement was maintained at the 6-month follow-up. Five acoustic features were analyzed. Speech intensity, vowel space, and speech rate changed significantly in positive directions immediately post-treatment, and the increases were retained up to six months. Global pitch variation increased immediately post-treatment but not at the 6-month follow-up. No changes were found in local pitch variation following treatment. Self-reported intelligibility, voice quality, confidence, frustration level, and communicative participation changed positively immediately after the completion of treatment and at the 6-month follow-up. To conclude, the speech characteristics of Mandarin speakers with PD were generally consistent with those of English speakers with PD, except that speech was slower in the Mandarin speakers. Cueing to increase loudness and reduce rate had different effects on speech intelligibility and production, with louder speech yielding greater intelligibility and acoustic benefits. Following intensive voice treatment (LSVT LOUD), Mandarin speakers with PD increased their vocal intensity. Speech intelligibility, vowel space, global pitch variation and speech rate increased as a result of the treatment. Thus, some differences between Mandarin and English dysarthria and effects of cueing might be present, but as for English speakers, intensive treatment (specifically LSVT LOUD) focusing on increasing vocal intensity shows promise for increasing intelligibility and quality of life in Mandarin speakers with hypokinetic dysarthria. Future studies should include a larger number of participants and probe the effects of behavioral speech modifications and intensive voice treatment on lexical tone, and consider which physiological mechanisms might be associated with production of lexical tone, given that lexical tone is often crucial to differentiating word meaning in Mandarin.

Two studies of voluntary movement in Parkinson's disease were carried out. In the first study, both parkinsonians and age-matched controls performed unconstrained prehensile movements in which subjects produced reaching and grasping (hand opening/closing) movements under varying conditions of movement amplitude, speed and object size. The act of prehension requires the intersegmental coordination of limb transport and grasp trajectories. Although parkinsonians were slower overall than controls, patients and controls similarly adjusted the spatial and temporal characteristics of their limb movement and grasp in response to changes in task demands. All groups showed increases in the speed of limb transport, the speed of hand opening and began hand opening proportionately earlier at faster movement speeds. All groups similarly increased hand opening velocity and initiated grasp earlier for smaller amplitude movements. Likewise, grasp was initiated earlier when reaching for wider objects. However, in contrast to controls, the onset time of hand opening during limb transport was delayed in these patients and was found to be more closely coupled with the timing of limb transport than in the controls. Moreover, patients showed greater curvature in their motion paths at the wrist during limb transport suggesting that the timing of joint motion (shoulder and elbow) may be different in these patients as well. Underlying differences between the groups in the temporal sequencing of movement are discussed. / In a second study, parkinson and control subjects performed continuous tracking movements in pursuit of sinusoidal and constant-speed target trajectories varying in frequency and amplitude. This task provided explicit temporal and spatial accuracy constraints by requiring subjects to reproduce the precise trajectory (i.e., velocity profile) of target movement. The results show that patients, similar to controls, were capable of modifying peak movement velocity while varying their times to reversal (i.e., movement durations) in response to changes in the movement time requirements of target motion. Indeed, both patients and controls were shown to alter the timing of movement deceleration in order to maintain their movement durations within the temporal limits of target movement. In contrast to controls, patients show progressive reduction in endpoint accuracy (undershooting the target) and, hence, reduced movement amplitudes, over the course of the trial. However, when endpoint accuracy requirements were reduced, by providing mechanical constraints on movement amplitude, patients were able to increase movement amplitudes while satisfying the temporal requirements of the task. These results are interpreted in terms of tradeoffs in performance between competing spatial and temporal demands of pursuit tracking. The significance of movement accuracy constraints on motor function in parkinsonian performance is discussed.

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The motivation of this study was to examine the effects of intensive speech treatment on the conversational intelligibility of Spanish speakers with Parkinson’s Disease (PD). It also aimed at investigating several acoustic variables in the speech of this population. Sixteen speakers with a medical diagnosis of PD participated in this study and their voice recordings were analyzed pre- and post-treatment. The intelligibility measures of transcription accuracy and median ease-of-understanding ratings increased significantly immediately post-treatment and gains were maintained at the one-month follow-up. The acoustic variables of vowel space and voice onset time did not change significantly pre-to-post treatment, whilst the prosodic targets of intensity and mean fundamental frequency increased significantly as a result of treatment. These findings support the implementation of intensive voice intervention to improve intelligibility in Spanish dysarthria. Clinical and theoretical considerations are discussed.

The effect of concurrent music on gait was investigated amongst Parkinson‟s disease (PD) patients and age-matched control subjects. Ten people (mean age 66.6 ± 6.5 years) with idiopathic Parkinson‟s disease and ten healthy age-matched (mean age 65.4 ± 6.3 years) control subjects completed steady state gait, dual task and obstacle negotiation trials in two differing test conditions; no music and whilst listening to music. Testing conditions were counterbalanced between subjects. The gait performance of PD patients was detrimentally affected by concurrently listening to music during steady state gait and obstacle negotiation, an effect that was further compounded in the dual task context. These findings imply that listening to music concurrent to gait may increase the attentional cost for PD patients. The findings of these studies have implications for patients, who may be at greater risk of falls in multi-task situations. / xi, 113 leaves ; 29 cm. --

L'analyse quantitative de la parole est pratiquée couramment en milieu clinique. Il s'agit d'un moyen d'évaluation non-invasif en vue de la documentation quantitative de la qualité de voix, et de son suivi au cours du temps. En milieu clinique, les méthodes d'analyse de signaux de parole doivent être fiables pour traiter des signaux de parole de locuteurs dysphoniques et âgés. De plus, les résultats de ces analyses doivent pouvoir se résumer à un faible nombre d'indices acoustiques pertinents et interprétables par les cliniciens.<p><p><p>Dans le cadre de cette thèse, nous nous sommes intéressés à la caractérisation des modulations basse-fréquence du signal de parole, et à son application à des locuteurs atteints de la maladie de Parkinson et à des locuteurs normophoniques. <p><p>Nous avons étudié d'une part l'estimation des modulations de la fréquence phonatoire, qui est la fréquence fondamentale du signal de parole. D'autre part, nous avons examiné les méthodes de caractérisation des modulations des fréquences des formants, qui sont les effets des résonances du conduit vocal dans le signal de parole. Nous avons développé des méthodes basées sur des transformées en ondelettes continues pour analyser ces modulations. Nous nous sommes également intéressés à l'application de méthodes d'estimation d'un conduit vocal acoustiquement équivalent à partir du signal de parole. <p><p>Nous avons appliqué ces méthodes à des signaux de parole de trois corpora. Le premier corpus est composé de locuteurs atteints de la maladie de Parkinson et de locuteurs normophoniques, le deuxième de locuteurs parkinsoniens enregistrés dans deux états pharmacologiques, et le troisième de locuteurs parkinsoniens enregistrés avant et après une thérapie vocale. Des analyses statistiques ont montré des différences significatives entre les indices de modulation en fonction de l'état de santé, en fonction de l'état pharmacologique, et au cours de la thérapie vocale. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished

A gold standard measurement does not exist to assess fatigue symptoms across patient populations. Current tools only consist of self-report measures that may not assess fatigue objectively. The National Institutes of Health-Brief Fatigue Inventory (NIH-BFI) is a clinician-administered instrument developed as a more objective assessment of fatigue symptoms. This study assessed the NIH-BFI's validity in diverse clinical populations, which included patients diagnosed with a mood disorder, Parkinson's disease, cancer, and healthy controls. Results suggest good criterion-related and convergent validity for the NIH-BFI. Results also indicate significant differences in fatigue severity between cohorts. Moreover, the data also suggest significant differences among groups in depression, anxiety, pain catastrophizing, sleep quality, global mental and physical health, and cognitive functioning. This study proposes that the NIH-BFI is a valid clinician-administered measure of fatigue that can be administered in multiple clinical populations.