Bereitschaftspotential in depressed and non-depressed patients with Parkinson's disease.

Impaired initiation and slowed execution of movements are two of the principal characteristics of Parkinson's disease (PD). A similar pattern of movement impairments (psychomotor retardation) can be seen frequently in patients with idiopathic depression. In addition, affective disorders have been frequently reported in patients with different basal ganglia disorders. The aim of this study was to determine whether there are some particularities in the cerebral electrical activity during the preparation and execution of voluntary internally paced movements (i.e., Bereitschaftspotential, BP) in depressed PD patients, which can distinguish them from non-depressed PD patients, as well as from healthy controls. The BPs were recorded in 16 patients with idiopathic PD, eight of whom were depressed (PD-D), and eight of whom were not (PD-ND). Additional recordings were taken from a group of eight age- and sex-matched healthy subjects. Depression was classified using the Research Diagnostic Criteria and the two PD groups were matched for age, disease severity, and disease duration. The amplitudes and slopes of the BPs from PD patients were generally smaller than in controls, but there was no specific pattern of BP changes that distinguished depressed from non-depressed PD patients. In addition, there was no particular association between measures of depression severity and BP parameters. The data suggest that presence of depression in PD might not have any additional deteriorating influence on already impaired preparation for self-paced spontaneous movements.

Depression in Parkinson's disease: an EEG frequency analysis study.

Although depression is a common finding in Parkinson's disease (PD), its neurobiological mechanism is still unknown. The purpose of this study was to determine whether there are specific spectral electroencephalographic (EEG) characteristics that distinguish depressed from non-depressed PD patients. The study was performed in 24 patients with idiopathic PD whose antiparkinson medication was stopped 24h beforehand. They were divided into two groups of 12 patients each, one with depressive symptomatology, and one without. The groups did not differ with respect to age, sex distribution, and disease severity and duration. All recordings were conducted using a 16-channel electroencephalograph, and artifact-free EEG was processed using a Fast Fourier Transformation. The EEG of depressed PD patients showed significantly less absolute and relative power in spectral band 7.5-10Hz (alpha1), and slightly more relative power in spectral band 10.513Hz (alpha2), while there was no difference in other spectral bands. Topographic analysis of the alpha1 absolute power revealed that, while in non-depressed patients this activity has a clear occipital maximum (and thus corresponds to the standard background activity), in depressed patients its maximum was shifted anteriorally toward the parietal region. Topographic analysis of the significance of the difference between the groups in the relative power of alpha1 and alpha2 bands revealed opposite gradients, posterior to anterior and anterior to posterior directions, respectively. The spectral EEG characteristics of the depressed PD patients not only differed from the spectral EEG characteristics of non-depressed PD patients, but they were also different from the usually reported spectral EEG characteristics of depressed patients without neurological disease. We propose that our data are sufficient to raise the possibility for the existence of a distinctive neurobiological substrate of depression in PD. This is not just a simple addition of two neurobiological substrata, one of depression (as it is determined in non-neurological patients) and one of PD, but rather a complex product of their interaction.

Prolactin and cortisol responses to fenfluramine in Parkinson's disease.

Dysfunction of the central serotonergic system has been associated with depression in Parkinson's disease. To evaluate central serotonergic function in Parkinson's disease in relation to depression, we examined prolactin and cortisol responses to a single-dose challenge with fenfluramine (60 mg orally), a serotonin releasing/uptake-inhibiting agent, in the course of 5 hours in 11 patients with Parkinson's disease associated with major depression (SADS-RDC), 22 nondepressed parkinsonians, and 20 age- and gender-matched healthy controls. No difference in cortisol responses were observed between the groups; however, prolactin responses to fenfluramine were significantly impaired in patients with Parkinson's disease compared to controls, and the response was significantly more blunted in parkinsonian patients with major depression in comparison with the nondepressed ones. These findings indicate that there is a diminished serotonergic responsivity in depression associated with Parkinson's disease.

Personality dimensions of opiate addicts.

A survey of 80 opiate addicts included in a detoxification program was conducted at the Institute on Addictions in Belgrade. In addition to a dependence diagnosis and mental disorders based on DSM-III-R, we applied a Tridimensional Personality Questionnaire (TPQ) that measures the 3 major personality dimensions: novelty-seeking (NS), harm avoidance (HA) and reward dependence (RD). When compared with a control group (a sample of Yugoslav undergraduate students), the opiate addicts demonstrate significantly high NS dimension as well as significant divergences of HA and RD subscales. The surveyed opiate addicts demonstrate a high percentage of personality disorders specifically in cluster B. The personality dimensions of opiate addicts showed certain temperament traits, such as: impulsiveness, shyness with strangers, fear of uncertainty and dependence. NS, HA and RD determined by temperament specifics may be an etiological factor in forming of a personality disorder, an affective disorder as well as of a drug choice.

The premorbid personality of patients with Parkinson's disease: evidence with the Tridimensional Personality Questionnaire.

The premorbid personality traits of 102 patients with Parkinson's disease (PD) and 57 age-matched healthy controls were studied by the recently developed Tridimensional Personality Questionnaire. We found significantly fewer (p < 0.05) of a group of traits called "novelty seeking" (NS), but no changes in "harm avoidance" (HA) and "reward dependence" (RD), in PD patients, for the period approximately 5-10 years before the onset of the disease, compared to controls. Individuals who are lower than average in NS and average in HA and RD are described as reflective, rigid, loyal, stoic, slow-tempered, frugal, orderly, and persistent Since NS is thought to be directly related to central dopaminergic reactivity, the premorbid expression of these behaviors may be the reflection of neurochemical deficits (hypodopaminergic tone) accompanying the presymptomatic phase of PD.

Effect of age at onset on frequency of depression in Parkinson's disease.

In a consecutive series of 169 outpatients with Parkinson's disease the frequency of depression was compared in two groups: those who developed Parkinson's disease before the age of 50, and those who developed the disease after 50. Major depression was found in 36% of patients with early onset and in 16% of patients with late onset Parkinson's disease. This significant difference disappeared when both groups were matched for duration of Parkinson's disease. A stepwise regression analysis in both the early onset and the late onset Parkinson's disease showed a significant correlation only between depression scores and the impairment scores of activities of daily living.