Marcelo Merello

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We studied 45 non-demented patients with Parkinson's disease (PD), 12 with progressive supranuclear palsy (PSP), 10 with multiple system atrophy (MSA) and 12 with neuroleptic-induced parkinsonism (NIP) for the presence of apraxia. Our aim was to determine whether a standard comprehensive assessment of different praxic functions would demonstrate specific(More)
Although apraxia is one of the most frequent signs in corticobasal degeneration, the phenomenology of this disorder has not been formally examined. Hence 10 patients with corticobasal degeneration were studied with a standardised evaluation for different types of apraxia. To minimise the confounding effects of the primary motor disorder, apraxia was(More)
OBJECTIVES To examine the clinical correlates of catatonia in depression, to validate a scale for catatonia, and to assess the validity of the DSM-IV criteria of the catatonic features specifier for mood disorders. METHODS A series of 79 consecutive patients with depression and 41 patients with Parkinson's disease without depression were examined using(More)
Current concepts regarding the organisation of the motor system indicate the existence of a frontoparietal circuit involved in prehension and manipulation, whose damage may result in a motor behavioural disorder strongly resembling the one originally described as limb-kinetic apraxia. To determine the specific clinical and kinematic features of this(More)
BACKGROUND AND PURPOSE Pathological gambling (PG) in Parkinson's disease (PD) is a frequent impulse control disorder associated mainly with dopamine replacement therapy. As impairments in decision-making were described independently in PG and PD, the objective of this study was to assess decision-making processes in PD patients with and without PG. (More)
Sleep benefit (SB) In Parkinson's disease (PD) is not well characterized. To determine SB frequency, as well as to characterize and correlate it with other disease variables, we evaluated prospectively a consecutive series of 312 PD patients by means of a structured questionnaire: 55% reported having SB and 35% reported that awakening was their best time of(More)
BACKGROUND There is a clear need for brief, sensitive and specific cognitive screening instruments in Parkinson's disease (PD). OBJECTIVES To study Addenbrooke's Cognitive Examination (ACE) validity for cognitive assessment of PD patient's using the Mattis Dementia Rating Scale (MDRS) as reference method. A specific scale for cognitive evaluation in PD,(More)
We examined the prevalence of major depression and dysthymia in 78 patients with the classic variant of Parkinson's disease (PD) (that is, tremor plus rigidity and/or bradykinesia), and in 34 patients with the akinetic-rigid variant. Although the prevalence of dysthymia was similar in both groups (classic PD, 31%; and akinetic-rigid PD, 32%), patients with(More)
OBJECTIVE To examine the differential impairment of implicit and explicit memory systems in cortical and subcortical dementias. BACKGROUND Whereas verbal priming was reported to be impaired in patients with Alzheimer Disease (AD), patients with Parkinson Disease (PD) may be relatively more impaired on tasks of motor skill learning. METHODS We examined(More)
It has been suggested that potential risk of hemiballismus after subthalamotomy makes DBS preferable to ablation for IPD treatment; however, cost and the need for regular electrode control have also been observed as disadvantages to stimulation. The objective was to compare efficacy and safety of different surgical approaches to STN, in a prospective(More)