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A professional violinist reported increasing difficulties playing the violin. He executed the initial half of the musical piece well, but produced an increasing number of mistakes during the second half. Neurological examination was remarkable for bradykinesia and tremor. Formal acoustic analysis of finger taps and pronation-supination showed a decrement in sound intensity and number of taps over time. Oscillations in performance correlated with a parkinsonian tremor. We interpret these findings as the audible equivalent of bradykinesia and tremor. Listening to bradykinesia and quantifying its decrement using acoustic analysis may offer a simple, objective, and reliable supplement to the neurological examination. Ann Neurol 2018;84:931-933., (© 2018 American Neurological Association.)

Background: Clinical and anecdotal observations propose that patients with Parkinson's disease (PD) may show drug-induced dyskinesia (DID) concomitantly with cardinal motor features. However, the extent of the concomitant presence of DID and cardinal features remains to be determined., Objectives: This cross-sectional study measured peak-dose choreic-type DID in a quantitative manner in patients diagnosed with PD, and determined whether symptoms such as tremor, bradykinesia, rigidity, postural instability or freezing of gait (FoG) were still detectable in these patients., Methods: 89 patients diagnosed with PD were recruited and assessed using a combination of quantitative measures using inertial measurement units to capture DID, tremor, bradykinesia, and FoG. Clinical evaluations were also used to assess rigidity and postural instability. Motor symptoms of PD were assessed 3 times during the testing period, and a series of activities of daily living were repeated twice, in between clinical tests, during which the level of DID was quantified. Peak-dose was identified as the period during which patients had the highest levels of DID. Levels of tremor, rigidity, bradykinesia, postural instability, and FoG were used to determine the percentage of patients showing these motor symptoms simultaneously with DID., Results: 72.4% of patients tested presented with measurable DID during the experiment. Rest, postural and kinetic tremor (12.7% , 38.1% , and 15.9% respectively), bradykinesia (28.6% ), rigidity (55.6% ), postural instability (71.4% ) and FoG (9.5% ) were detected simultaneously with DID., Conclusions: PD symptomatology remains present in patients showing peak-dose choreic-type DID, illustrating the challenge facing physicians when trying to avoid dyskinesia while attempting to alleviate motor symptoms.

Expectation contributes to placebo and nocebo responses in Parkinson's disease (PD). While there is evidence for expectation-induced modulations of bradykinesia, little is known about the impact of expectation on resting tremor. Subthalamic nucleus (STN) deep brain stimulation (DBS) improves cardinal PD motor symptoms including tremor whereas impairment of verbal fluency (VF) has been observed as a potential side-effect. Here we investigated how expectation modulates the effect of STN-DBS on resting tremor and its interaction with VF. In a within-subject-design, expectation of 24 tremor-dominant PD patients regarding the impact of STN-DBS on motor symptoms was manipulated by verbal suggestions (positive [placebo], negative [nocebo], neutral [control]). Patients participated with (MedON) and without (MedOFF) antiparkinsonian medication. Resting tremor was recorded by accelerometry and bradykinesia of finger tapping and diadochokinesia were assessed by a 3D ultrasound motion detection system. VF was quantified by lexical and semantic tests. In a subgroup of patients, the effect of STN-DBS on tremor was modulated by expectation, i.e. tremor decreased (placebo response) or increased (nocebo response) by at least 10% as compared to the control condition while no significant effect was observed for the overall group. Interestingly, nocebo responders in MedON were additionally characterized by significant impairment in semantic verbal fluency. In contrast, bradykinesia was not affected by expectation. These results indicate that the therapeutic effect of STN-DBS on tremor can be modulated by expectation in a subgroup of patients and suggests that tremor is also among the parkinsonian symptoms responsive to placebo and nocebo interventions. While positive expectations enhanced the effect of STN-DBS by further decreasing the magnitude of tremor, negative expectations counteracted the therapeutic effect and at the same time exacerbated a side-effect often associated with STN-DBS. The present findings underscore the potency of patients' expectation and its relevance for therapeutic outcomes.

Background and Aims: (1) To establish the prevalence of mild cognitive impairment (MCI) in newly diagnosed drug-naive patients with Parkinson's disease adopting recently proposed and more conservative preliminary research criteria. (2) To investigate the relation between cognitive performances, MCI and motor dysfunction., Methods: 132 consecutive newly diagnosed drug-naive PD patients and 100 healthy controls (HCs) underwent a neuropsychological evaluation covering different cognitive domains. Moreover, on the basis of the Unified Parkinson's Disease Rating Scale II/III, different motor scores were calculated and patients were classified in motor subtypes. 11 patients were excluded from the analysis during clinical follow-up which was continued at least 3 years from the diagnosis; therefore, the final sample included 121 patients., Results: MCI prevalence was higher in PD (14.8%) patients than in HCs (7.0%). PD patients reported lower cognitive performances than HCs in several cognitive domains; HCs also outperformed cognitively preserved PD patients in tasks of episodic verbal memory and in a screening task of executive functions. MCI-PD patients presented a more severe bradykinesia score than non-MCI PD patients and patients mainly characterised by tremor had better performances in some cognitive domains, and specific cognitive-motor relationships emerged., Conclusions: Although the adoption of more conservative diagnostic criteria identified a lower MCI prevalence, we found evidence that newly diagnosed drug-naive PD patients present a higher risk of MCI in comparison with HCs. Axial symptoms and bradykinesia represent risk factors for MCI in PD patients and a classification of PD patients that highlights the presence/absence of tremor, as proposed in this study, is probably better tailored for the early stages of PD than classifications proposed for more advanced PD stages.

We aimed to evaluate the clinical factors predicting response to dopaminergic treatment for resting tremor in patients with Parkinson's disease (PD). Eighty-five PD patients with prominent resting tremor, defined as tremors of score greater than 3 in at least one limb on the Unified Parkinson's Disease Rating Scale (UPDRS), were divided into those responsive or nonresponsive to dopaminergic treatment. Responsiveness was defined as a reduction of at least two points for more than 3 months in the UPDRS tremor score. Of the 85 patients, 36 (42.4%) were responsive and 49 (57.6%) were nonresponsive to dopaminergic treatment. Initial UPDRS III score (P = 0.015) and Hoehn and Yahr stage (P = 0.010) were each significantly higher in the RG than in the NRG. UPDRS subscores for rigidity (P = 0.012), bradykinesia (P = 0.021) and postural impairment (P = 0.018) also correlated with responsiveness to dopaminergic treatment. Resting tremor in PD patients was more responsive to dopaminergic treatment when accompanied by moderate degrees of bradykinesia and rigidity than in patients without other prominent parkinsonian features., (2007 Movement Disorder Society)

The kinematics characteristics of an upper arm extension of large amplitude (90 degrees) performed in the horizontal plane and the simultaneous activity of the shoulder muscles were recorded in 12 parkinsonian patients and in six normal control subjects. The movement, triggered by an acoustic "go" signal, was preceded by an isometric adduction. Within the whole population of individuals (n = 18) a strong, positive correlation was observed between the root mean square value of agonist EMG activity, evaluated during the acceleration phase of the movement, and both peak velocity and acceleration. In six patients tremor bursts at the frequency of 8-14 Hz (action tremor) were observed during the movement phase in the anterior, middle, and posterior deltoid: all these patients showed low root mean square values and were bradykinetic with respect to the control subjects. The remaining six patients did not show this action tremor during the movement phase. All but one had an agonist activation of normal duration and amplitude, showed high root mean square values, and performed well in the range of control subjects. We conclude that the inability to suppress the activity of pathological oscillator(s) responsible for the action tremor plays a fundamental role in the bradykinesia associated with Parkinson's disease.

The author summarises the various origins of hand tremor. Physiologic tremor can be demonstrated in any individual. This tremor is normally recordable at a stable frequency of 8-10 Hz, though this can be influenced by age, the amplitude can vary substantially. Physiological tremor is believed to have its origin in the mechanical properties of the extremities, and the firing properties of motoneurones. Essential tremor is an inherited autosomally dominant phenomenon, and is characterised by action and postural tremor. It is progressive with age. The use of low doses of theophylline in the treatment of essential tremor is emphasised, in view of the low incidence of side effects. A hypothesis is also presented to account for essential tremor in terms of an imbalance in the activity of excitatory and inhibitory amino acid system. Parkinsonian tremor may begin as postural or resting tremor on one side, and it is reduced by active movement of the affected extremity. The prognosis of Parkinson's disease presenting with tremor is better when presenting with hypokinesia. The increasing use of non-specific drugs in the treatment of Parkinsonism, and the use of thalamic high frequency stimulation are indicated.