ABSTRACT
OBJECTIVE: To investigate whether pre-attentive auditory discrimination is impaired in patients with essential tremor (ET) and to evaluate the role of age at onset in this function. METHODS: Seventeen non-demented patients with ET and seventeen age- and sex-matched healthy controls underwent an EEG recording during a classical auditory MMN paradigm. RESULTS: MMN latency was significantly prolonged in patients with elderly-onset ET (>65 years) (p=0.046), while no differences emerged in either latency or amplitude between young-onset ET patients and controls. CONCLUSIONS: This study represents a tentative indication of a dysfunction of auditory automatic change detection in elderly-onset ET patients, pointing to a selective attentive deficit in this subgroup of ET patients. SIGNIFICANCE: The delay in pre-attentive auditory discrimination, which affects elderly-onset ET patients alone, further supports the hypothesis that ET represents a heterogeneous family of diseases united by tremor; these diseases are characterized by cognitive differences that may range from a disturbance in a selective cognitive function, such as the automatic part of the orienting response, to more widespread and complex cognitive dysfunctions.
Subject(s)
Attention/physiology , Auditory Perception/physiology , Discrimination, Psychological/physiology , Essential Tremor/physiopathology , Evoked Potentials/physiology , Age of Onset , Aged , Aged, 80 and over , Electroencephalography , Female , Humans , Male , Middle AgedABSTRACT
Clinically subtle executive dysfunctions have recently been described in essential tremor (ET), though the presence of attentional deficits is still unclear. We investigated the psychophysiological aspects of attention in ET, using event-related potentials (ERPs). Twenty-one non-demented patients with ET and 21 age- and sex-matched healthy controls underwent a psychophysiological evaluation. P300 components and the Contingent Negative Variation (CNV) were recorded. The latencies and amplitudes of the P3a and P3b subcomponents and CNV areas were evaluated. Possible correlations between clinical parameters and ERP data were investigated. P3a latency was significantly longer in the ET group (p < 0.05), while no differences emerged between patients and controls in P3b latency. No differences were observed between the two groups in the CNV parameters. ET patients display a difficulty in the response to novelty and in the recruitment of prefrontal attentive circuits, while the memory context-updating process appears to be spared. This selective cognitive dysfunction does not appear to interfere with the attentional set linked to the expectancy evaluated during a complex choice-reaction time task, which is preserved in ET. This multitask psychophysiological approach reveals the presence of a peculiar attentional deficit in patients with ET, thus expanding the clinical features of this disease.
Subject(s)
Attention Deficit Disorder with Hyperactivity/diagnosis , Attention Deficit Disorder with Hyperactivity/etiology , Contingent Negative Variation/physiology , Essential Tremor/complications , Evoked Potentials/physiology , Adult , Aged , Aged, 80 and over , Brain Mapping , Case-Control Studies , Chi-Square Distribution , Electroencephalography , Female , Humans , Male , Middle Aged , Psychophysics , Reaction Time/physiologySubject(s)
Headache Disorders/diagnosis , Headache Disorders/epidemiology , Neck Muscles/physiopathology , Torticollis/diagnosis , Torticollis/epidemiology , Aged , Botulinum Toxins, Type A/therapeutic use , Case-Control Studies , Comorbidity , Female , Headache Disorders/drug therapy , Humans , Incidence , Male , Middle Aged , Neck Muscles/drug effects , Neuromuscular Agents/therapeutic use , Torticollis/drug therapy , Treatment OutcomeABSTRACT
Excessive daytime somnolence (EDS) and quality of sleep were studied in 25 parkinsonian patients at baseline, when they had not yet received any antiparkinsonian medication, and after 1 year of treatment with dopaminergic drugs. EDS was measured by the Epworth Sleepiness Scale (ESS) and sleep quality by the Pittsburgh Sleep Quality Index (PSQI). At baseline, the ESS score was not different from that of age-matched healthy controls. The mean ESS score increased significantly after 1 year of follow-up, being more than 10 in 12 patients. The mean PSQI also increased significantly after 1 year of treatment, but there were no differences in the number of "bad sleepers" at baseline and at follow-up. In conclusion, EDS seems to emerge during the course of the illness, at least in a proportion of PD patients, and could represent another clinical correlate of the interaction between the ongoing neurodegenerative process and the side effects of drugs.
Subject(s)
Antiparkinson Agents/therapeutic use , Disorders of Excessive Somnolence/etiology , Parkinson Disease/complications , Parkinson Disease/drug therapy , Activities of Daily Living , Aged , Case-Control Studies , Female , Follow-Up Studies , Humans , Male , Mental Status Schedule , Middle Aged , Motor Activity , Neuropsychological TestsABSTRACT
As cholinergic mechanisms may be at least partially responsible for hallucinations and delusions in Parkinson's disease (PD), we conducted an open study in 8 PD patients to assess the efficacy and tolerability of the cholinesterase inhibitor donepezil, 5 mg at bedtime for two months, in the treatment of these complications. Hallucinations and delusions improved significantly in all patients. Donezepil was overall well tolerated, but a deterioration in motor disability was noted in 2 out of 8 patients.
