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1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3666-3669, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018796

RESUMO

This study has investigated the efficiency of voice features in estimating the motor Unified Parkinson's Disease Rating Scale (UPDRS) score in Parkinson's disease (PD) patients. A total of 26 PD patients (mean age = 72) and 22 control subjects (mean age = 66.91) were recruited for the study. The sustained phonation /a/, /u/ and /m/ were collected in both off-state and on-state of Levodopa medication. The average motor UPDRS for PD off-state patients was 27.31, on-state was 20.42 and that of controls was 2.63. Voice features were extracted from the phonation tasks and were reduced to the most relevant 6 features for each phonation task using the Least Absolute Shrinkage and Selection Operator (LASSO) feature ranking method. The correlation between the reduced features and motor UPDRS was tested using the Spearman correlation coefficient test. AdaBoost regression learner was trained and used for automatically estimating the motor UPDRS score using the voice features. The results show that the vocal features for /m/ performed best by estimating the motor UPDRS score for PD off-state with the mean absolute error (MAE) of 3.52 and 5.90 for PD on-state. This study shows that assessment of voice can be used for day to day remote monitoring of PD patients.


Assuntos
Doença de Parkinson , Voz , Humanos , Levodopa/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Fonação
4.
Cortex ; 125: 161-174, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31991241

RESUMO

Functional motor disorders (FMDs) are distinguished by signs that lack congruence with recognised patterns of organic disease and show inconsistency over time. Their pathophysiology is poorly understood, but there is evidence that irregularities in perceptual and cognitive processing lie at the heart of these conditions. Here, we draw on a predictive coding account of functional neurological disorders to study perceptual decision-making in three groups: 20 patients with FMDs (14 with functional movements and 6 with functional weakness), 20 with phenotypically-matched organic motor disorders, and 20 age-matched healthy controls. We examine four cognitive domains with putative roles in FMD pathogenesis: attention, expectations, sensory processing (perceptual sensitivity), and metacognition (introspective evaluation of performance). We augmented a dual-task paradigm, manipulating the visual contrast required for target detection to examine these domains in one design. With sensory input (stimulus contrast) psychometrically adjusted to staircase target detection at a fixed level for all groups, the FMD group exhibited statistically equivalent attentional, expectational and metacognitive processing to healthy controls. However, we demonstrate Bayesian evidence and a frequentist trend that FMD patients require higher visual contrast than controls to maintain the same detection sensitivity (BF10 = 8.1, pholm = .066). This was statistically equivalent to the visual contrast required by the organic group, and unlikely to be accounted for by medication use or comorbid psychopathology. The organic group showed differences in processing of attention and expectations for target detection that were not observed in either healthy controls or the functional group. The distinctive behavioural profile of FMDs may arise from abnormalities in basic sensory processing, while higher attentional, expectational and metacognitive mechanisms remain intact. Conceptualising functional neurological disorders under a predictive coding account may consolidate and refine existing pathophysiological theories about them.

5.
Med Humanit ; 46(1): 31-45, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31366718

RESUMO

Though John Ruskin (1819-1900) is remembered principally for his work as a theorist, art critic and historian of visual culture, he wrote exhaustively about his health in his correspondence and diaries. Ruskin was prone to recurring depressive and hypochondriacal feelings in his youth and adulthood. In 1871, at the age of 52 years, he developed an illness with relapsing psychiatric and neurological features. He had a series of attacks of brain disturbance, and a deterioration of his mental faculties affected his writing for years before curtailing his career a decade before he died. Previous writers have suggested he had a psychiatric malady, perhaps schizophrenia or schizoaffective disorder. But the more obvious conclusion from a close medical reading of Ruskin's descriptions of his illness is he had some sort of 'organic' brain illness. This paper aims to give insight into the relationship between Ruskin's state of well-being and the features of his writing through a palaeographical study of his letters and diary entries. We examine the handwriting for physical traces of Ruskin's major brain illness, guided by the historical narrative of the illness. We also examine Ruskin's recording of his experiences for what they reveal about the failure of his health and its impact on his work. Ruskin's handwriting does not have clear-cut pathological features before around 1885, though suggestions of subtle writing deficits were present as early as 1876. After 1887, Ruskin's handwriting shows fixed pathological signs-tremor, disturbed letter formation and features that reflect a slow and laborious process of writing. These observations are more than could be explained by normal ageing, and suggest the presence of a neurological deficit affecting writing control. Our findings are consistent with conclusions that we drew from the historical record-that John Ruskin had an organic neurological disorder with cognitive, behavioural, psychiatric and motor effects.


Assuntos
Escrita Manual , Doenças do Sistema Nervoso , Sistema Nervoso/patologia , Idoso , Pessoas Famosas , Humanos , Masculino , Transtornos Mentais/diagnóstico , Transtornos Mentais/etiologia , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/complicações , Doenças do Sistema Nervoso/diagnóstico
6.
Epilepsy Behav Rep ; 12: 100348, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31799510

RESUMO

•Hepatic encephalopathy may predispose to seizure-related cortical laminar necrosis.•Elevated ammonia levels potentially compound the excitotoxic effects of epilepsy.•Early identification and treatment of seizures in liver disease could be protective.

7.
Biosensors (Basel) ; 10(1)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861890

RESUMO

In this paper, we have investigated the differences in the voices of Parkinson's disease (PD) and age-matched control (CO) subjects when uttering three phonemes using two complexity measures: fractal dimension (FD) and normalised mutual information (NMI). Three sustained phonetic voice recordings, /a/, /u/ and /m/, from 22 CO (mean age = 66.91) and 24 PD (mean age = 71.83) participants were analysed. FD was first computed for PD and CO voice recordings, followed by the computation of NMI between the test groups: PD-CO, PD-PD and CO-CO. Four features reported in the literature-normalised pitch period entropy (Norm. PPE), glottal-to-noise excitation ratio (GNE), detrended fluctuation analysis (DFA) and glottal closing quotient (ClQ)-were also computed for comparison with the proposed complexity measures. The statistical significance of the features was tested using a one-way ANOVA test. Support vector machine (SVM) with a linear kernel was used to classify the test groups, using a leave-one-out validation method. The results showed that PD voice recordings had lower FD compared to CO (p < 0.008). It was also observed that the average NMI between CO voice recordings was significantly lower compared with the CO-PD and PD-PD groups (p < 0.036) for the three phonetic sounds. The average NMI and FD demonstrated higher accuracy (>80%) in differentiating the test groups compared with other speech feature-based classifications. This study has demonstrated that the voices of PD patients has reduced FD, and NMI between voice recordings of PD-CO and PD-PD is higher compared with CO-CO. This suggests that the use of NMI obtained from the sample voice, when paired with known groups of CO and PD, can be used to identify PD voices. These findings could have applications for population screening.


Assuntos
Técnicas Biossensoriais , Doença de Parkinson/diagnóstico , Máquina de Vetores de Suporte , Voz , Idoso , Humanos , Fonética
8.
J Clin Neurosci ; 69: 279-280, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31447362

RESUMO

A 23-year old man was found to have a Chiari Type 1 malformation and cerebellar atrophy. While this association has previously been described, the remote cerebellar atrophy is difficult to explain. We believe the answer lies with our finding of signal hyperintensity on MR imaging at the level of the inferior olives. This suggest hypertrophic olivary degeneration, caused by trans-synaptic degeneration following disruption to the Guillain-Mollaret triangle. Propagation of this process to the cerebellar Purkinje cells occurs in some cases. We describe a case in support of this hypothesis and review previously published evidence.


Assuntos
Malformação de Arnold-Chiari/patologia , Doenças Cerebelares/patologia , Núcleo Olivar/patologia , Degeneração Retrógrada/patologia , Malformação de Arnold-Chiari/complicações , Atrofia/patologia , Doenças Cerebelares/etiologia , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Adulto Jovem
10.
Front Neurol ; 10: 403, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31068893

RESUMO

Progressive micrographia is decrement in character size during writing and is commonly associated with Parkinson's disease (PD). This study has investigated the kinematic features of progressive micrographia during a repetitive writing task. Twenty-four PD patients with duration since diagnosis of <10 years and 24 age-matched controls wrote the letter "e" repeatedly. PD patients were studied in defined off states, with scoring of motor function on the Unified Parkinson's Disease Rating Scale Part III. A digital tablet captured x-y coordinates and ink-pen pressure. Customized software recorded the data and offline analysis derived the kinematic features of pen-tip movement. The average size of the first and the last five letters were compared, with progressive micrographia defined as >10% decrement in letter stroke length. The relationships between dimensional and kinematic features for the control subjects and for PD patients with and without progressive micrographia were studied. Differences between the initial and last letter repetitions within each group were assessed by Wilcoxon signed-rank test, and the Kruskal-Wallis test was applied to compare the three groups. There are five main conclusions from our findings: (i) 66% of PD patients who participated in this study exhibited progressive micrographia; (ii) handwriting kinematic features for all PD patients was significantly lower than controls (p < 0.05); (iii) patients with progressive micrographia lose the normal augmentation of writing speed and acceleration in the x axis with left-to-right writing and show decrement of pen-tip pressure (p = 0.034); (iv) kinematic and pen-tip pressure profiles suggest that progressive micrographia in PD reflects poorly sustained net force; and (v) although progressive micrographia resembles the sequence effect of general bradykinesia, we did not find a significant correlation with overall motor disability, nor with the aggregate UPDRS-III bradykinesia scores for the dominant arm.

11.
J Neurol ; 266(6): 1376-1382, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30877380

RESUMO

Levodopa treatment does improve Parkinson's disease (PD) dysgraphia, but previous research is not in agreement about which aspects are most responsive. This study investigated the effect of levodopa on the kinematics of writing. Twenty-four patients with PD of less than 10 years duration and 25 age-matched controls were recruited. A practically defined off state method was used to assess the levodopa motor response, measured on the Unified Parkinson's Disease Rating Scale Part III. The kinematic features for six handwriting tasks involving different levels of complexity were recorded from PD patients in off and on states and from the control group. Levodopa is effective for simple writing activities involving repetition of letters, denoting improved fine motor control. But the same benefit was not seen for copying a sentence and a written category fluency test, tasks that carry memory and cognitive loads. We also found significant differences in kinematic features between control participants and PD patients, for all tasks and in both on and off states. Serial testing of handwriting in patients known to be at risk for developing PD might prove to be an effective biomarker for cell loss in the substantia nigra and the associated dopamine deficiency. We recommend using a panel of writing tasks including sentence copying and memory dependence. Dual-task effects may make these activities more sensitive to early motor deficits, while their weaker levodopa responsiveness would cause them to be more stable indicators of motor progression once symptomatic treatment has been commenced.


Assuntos
Agrafia/tratamento farmacológico , Dopaminérgicos/farmacologia , Levodopa/farmacologia , Destreza Motora/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico , Idoso , Agrafia/etiologia , Fenômenos Biomecânicos , Feminino , Escrita Manual , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações
13.
Parkinsonism Relat Disord ; 60: 133-137, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30217541

RESUMO

INTRODUCTION: The long duration response to levodopa in Parkinson's disease outlasts drug elimination by days to weeks. Though a substantive part of anti-parkinsonian motor benefit, it cannot easily be observed. OBJECTIVES: To infer the magnitude of the long duration response during the first decade of Parkinson's disease and identify factors that influence it. METHODS: Serial practically defined off scores of 24 patients from a longitudinal study of levodopa short duration response were used to establish their rate of motor progression. A line of notional untreated disability (as if drug treatment had never been given) with the same progression gradient was the basis for calculation of the long duration response. Predictors of mean long duration response amplitude were identified using a multiple linear regression model. RESULTS: Over a mean treatment period of 16.6 ±â€¯4.4 years, annual increase in motor disability was 2.3% of the maximum score. The long duration response composed 49% of total levodopa response during the first decade of treatment, and this proportion was significantly higher soon after commencing levodopa (p = 0.001). Higher pre-treatment motor score (r = 0.60) and lower MMSE (r = 0.60) were the main predictors of a larger long duration response. There was little correlation between long and short duration responses. CONCLUSIONS: Long duration responses contribute almost half of the total levodopa benefit during the first decade of treatment. An appreciation of both long and short duration components of drug symptomatic effects is important in clinical trial design to investigate possible neuroprotective treatments.


Assuntos
Antiparkinsonianos/farmacologia , Progressão da Doença , Levodopa/farmacologia , Avaliação de Resultados em Cuidados de Saúde , Doença de Parkinson/tratamento farmacológico , Idoso , Antiparkinsonianos/administração & dosagem , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Feminino , Humanos , Levodopa/administração & dosagem , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações , Índice de Gravidade de Doença , Fatores de Tempo
14.
J Clin Neurosci ; 57: 167-168, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30172639

RESUMO

This report details prominent neuropsychiatric features in one family with an ADCY5 gene mutation. ADCY5 mutations cause a variable motor phenotype, though most cases have some core involuntary movement features. The psychiatric aspects of the disorder have not been emphasised in previous publications. We discuss possible pathogenesis.


Assuntos
Adenilil Ciclases/genética , Depressão/diagnóstico , Discinesias/diagnóstico , Fenótipo , Transtornos Psicóticos/diagnóstico , Adulto , Depressão/complicações , Depressão/genética , Discinesias/complicações , Discinesias/genética , Humanos , Masculino , Mutação , Transtornos Psicóticos/complicações , Transtornos Psicóticos/genética
15.
PLoS One ; 12(11): e0186611, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29099841

RESUMO

BACKGROUND: Voice change is one of the earliest features of Parkinson's disease. However, quantitative studies of vocal fold dynamics which are needed to provide insight into disease biology, aid diagnosis, or track progression, are few. METHODS: We therefore quantified arytenoid cartilage movements and glottic area during repeated phonation in 15 patients with Parkinson's disease (symptom duration < 6 years) and 19 controls, with 320-slice computerised tomography (CT). We related these measures to perceptual voice evaluations and spirometry. We hypothesised that Parkinson's disease patients have a smaller inter-arytenoid distance, a preserved or larger glottic area because vocal cord bowing has previously been reported, less variability in loudness, more voice dysdiadochokinesis and breathiness and a shortened phonation time because of arytenoid hypokinesis relative to glottic area. RESULTS: Inter-arytenoid distance in Parkinson's disease patients was moderately smaller (Mdn = 0.106, IQR = 0.091-0.116) than in controls (Mdn = 0.132, IQR = 0.116-0.166) (W = 212, P = 0.015, r = -0.42), normalised for anatomical and other inter-subject variance, analysed with two-tailed Wilcoxon's rank sum test. This finding was confirmed in a linear mixed model analysis-Parkinson's disease significantly predicted a reduction in the dependent variable, inter-arytenoid distance (b = -0.87, SEb = 0.39, 95% CI [-1.66, -0.08], t(31) = -2.24, P = 0.032). There was no difference in glottic area. On perceptual voice evaluation, patients had more breathiness and dysdiadochokinesis, a shorter maximum phonation time, and less variability in loudness than controls. There was no difference in spirometry after adjustment for smoking history. CONCLUSIONS: As predicted, vocal fold adduction movements are reduced in Parkinson's disease on repeated phonation but glottic area is maintained. Some perceptual characteristics of Parkinsonian speech reflect these changes. We are the first to use 320-slice CT to study laryngeal motion. Our findings indicate how Parkinson's disease affects intrinsic laryngeal muscle position and excursion.


Assuntos
Cartilagem Aritenoide/fisiopatologia , Doença de Parkinson/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Cartilagem Aritenoide/diagnóstico por imagem , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico por imagem , Tomografia Computadorizada por Raios X
16.
Mov Disord Clin Pract ; 4(4): 478-485, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28920067

RESUMO

Before 1911, when Hermann Oppenheim introduced the term dystonia, this movement disorder lacked a unifying descriptor. While words like epilepsy, apoplexy, and palsy have had their meanings since antiquity, references to dystonia are much harder to identify in historical documents. Torticollis is an exception, although there is difficulty distinguishing dystonic torticollis from congenital muscular torticollis. There are, nevertheless, possible representations of dystonia in literature and visual art from the pre-modern world. Eighteenth century systematic nosologists such as Linnaeus, de Sauvages, and Cullen had attempted to classify some spasmodic conditions, including torticollis. But only after Charcot's contributions to clinical neuroscience were the various forms of generalized and focal dystonia clearly delineated. They were categorized as névroses: Charcot's term for conditions without an identifiable neuroanatomical cause. For a time thereafter, psychoanalytic models of dystonia based on Freud's ideas about unconscious conflicts transduced into physical symptoms were ascendant, although there was always a dissenting "organic" school. With the rise of subspecialization in movement disorders during the 1970s, the pendulum swung strongly back toward organic causation. David Marsden's clinical and electrophysiological research on the adult-onset focal dystonias was particularly important in establishing a physical basis for these disorders. We are still in a period of "living history" of dystonia, with much yet to be understood about pathophysiology. Rigidly dualistic models have crumbled in the face of evidence of electrophysiological and psychopathological overlap between organic and functional dystonia. More flexible biopsychosocial frameworks may address the demand for new diagnostic and therapeutic rationales.

17.
Pract Neurol ; 17(6): 456-463, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28844041

RESUMO

When a patient presents with tremor, it can be useful to perform a few simple pen and paper tests. In this article, we explain how to maximise the value of handwriting and of drawing Archimedes spirals and straight lines as clinical assessments. These tasks take a matter of seconds to complete but provide a wealth of information that supplements the standard physical examination. They aid the diagnosis of a tremor disorder and can contribute to its longitudinal monitoring. Watching the patient's upper limb while they write and draw may reveal abnormalities such as bradykinesia, dystonic posturing and distractibility. The finished script and drawings can then be evaluated for frequency, amplitude, direction and symmetry of oscillatory pen movements and for overall scale of penmanship. Essential, dystonic, functional and parkinsonian tremor each has a characteristic pattern of abnormality on these pen and paper tests.


Assuntos
Exame Neurológico/métodos , Tremor/diagnóstico , Escrita Manual , Humanos
18.
J Physiother ; 63(2): 94-100, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28342682

RESUMO

QUESTIONS: For people with idiopathic Parkinson's disease, does a 6-week, comprehensive, home exercise program reduce falls and disability and improve health-related quality of life? Is the program cost-effective? DESIGN: Randomised, controlled trial with concealed allocation and assessor blinding. PARTICIPANTS: One hundred and thirty-three community-dwelling adults with Parkinson's disease. INTERVENTION: The experimental group completed a 6-week home program comprising progressive resistance strength training, movement strategy training and falls education. The control group completed 6 weeks of non-specific life skills training. Participants in both groups received weekly therapist-guided sessions for 6 consecutive weeks and a weekly self-directed home program. OUTCOME MEASURES: The primary outcome was the rate of falls, documented for the 12-month period immediately after therapy. Secondary outcomes were disability and health-related quality of life, assessed before and after intervention and at a 12-month follow-up. RESULTS: A total of 2255 falls were reported by the 12-month follow-up. The proportion of fallers in the experimental and control groups was 61 and 72%, respectively, which was not statistically significantly different (RR=0.85, 95% CI 0.66 to 1.09). There was no significant between-group difference in the rate of falls (incidence rate ratio=1.58, 95% CI 0.73 to 3.43). A survival analysis of participant time to first fall did not show a significant between-group difference (log-rank test χ2=0.79, p=0.37). No significant between-group differences occurred for mobility, disability or quality of life. The mean cost of delivering the experimental intervention was AUD1596. CONCLUSION: A home program of strength and movement strategy training and falls education does not prevent falls when applied at the dose used in this study. Arguably, the dosage of therapy was insufficient. Future trials need to explore further therapy content, repetitions and duration, in order to optimise outcomes and cost-effectiveness. [Morris ME, Taylor NF, Watts JJ, Evans A, Horne M, Kempster P, Danoudis M, McGinley J, Martin C, Menz HB (2017) A home program of strength training, movement strategy training and education did not prevent falls in people with Parkinson's disease: a randomised trial. Journal of Physiotherapy 63: 94-100].


Assuntos
Acidentes por Quedas/prevenção & controle , Serviços de Assistência Domiciliar/estatística & dados numéricos , Força Muscular , Doença de Parkinson/reabilitação , Educação de Pacientes como Assunto/métodos , Treinamento de Resistência/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Equilíbrio Postural , Projetos de Pesquisa
19.
Mov Disord ; 31(12): 1777-1784, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27753149

RESUMO

Mind-brain dualism has dominated historical commentary on dystonia, a dichotomous approach that has left our conceptual grasp of it stubbornly incomplete. This is particularly true of functional dystonia, most diagnostically challenging of all functional movement disorders, in which the question of inherent psychogenicity remains a focus of debate. Phenomenological signs considered in isolation lack the specificity to distinguish organic and nonorganic forms, and dystonia's variability has frustrated attempts to develop objective laboratory-supported standards. Diagnostic criteria for functional dystonia that place emphasis on psychiatric symptoms perform poorly in studies of reliability, partly explained by the high frequency of psychopathology in organic dystonia. Novel approaches from the cognitive neurosciences may offer a way forward. Theory on Bayesian statistical prediction in cognitive processing is supported by sufficient experimental evidence for this model to be taken seriously as a way of reconciling contradictory notions about voluntary and unconscious motor control in functional movement disorders. In a Bayesian formulation of functional dystonia, misallocation of attention and abnormal predictive beliefs generate movements that are executed without a sense of agency. Building on this framework, there is a consensus that a biopsychosocial approach is required and that a unified philosophy of brain and mind is the best way to locate dystonia in the neurology-psychiatry borderland. At a practical level, movement disorder neurologists are best placed to differentiate organic from functional dystonia. The main role of psychiatrists is in the diagnosis and management of the primarily psychiatric disorders that often accompany dystonia. © 2016 International Parkinson and Movement Disorder Society.


Assuntos
Distúrbios Distônicos , Transtornos Mentais , Humanos
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