Verification of the structure of the 16 P.F. Questionnaire in German

What is the evidence for a premorbid parkinsonian personality: a systematic review

Rigid and introverted personality type has been suggested as possibly associated with risk of Parkinson's disease (PD). However, to be a risk, the measurement of personality must precede the onset of PD, more than simply reported as personality in PD cases. Several reviews have been published examining the literature base for this suggestion; however, the issue of "premorbid" personality measurement was not emphasized. MEDLINE, EMBASE, and PSYCHINFO databases were searched for existing systematic reviews or meta-analyses, and none were found that fulfilled this criterion. The databases were searched systematically for primary research articles. Articles without robust methodology were excluded based on published quality scoring criteria. No articles met all selection criteria. Four articles met most selection criteria and three of them reported significant differences in personality features said to be present before PD onset and between PD cases and controls. PD cases were more introverted, cautious, socially alert, and tense than controls. Although the instruments used to characterize personality varied widely across studies, the general descriptions of PD patients included nervous, cautious, rigid, and conventional. There do appear to be parkinsonian characteristics, but these studies were all retrospective. To confirm that personality traits precede PD onset and are a risk for this condition, prospective research is required. Even then, the term "premorbid" is difficult to define due to the unknown latent period before onset of PD. Additional research would involve correlating personality characteristics to activities or changes in the brain.

The electroencephalogram (EEG) as a research tool in human behavior genetics: psychological examinations in healthy males with various inherited EEG variants. I. Rationale of the study. Material. Methods. Heritability of test parameters

In the first section of this paper, various research designs in human behavior genetics are compared. In this context, the commonly used concept of biometric genetics is critically evaluated from the point of view of science theory. It is contrasted with the Mendelian gene concept, which, in principle, leads to a much deeper theoretical understanding by offering clues for basic mechanisms. To explore this advantage fully, a research strategy is needed that first looks for genetic variability in a physiological parameter of possible importance for human behavior and then tries to explore the influence of this parameter on the function of the human brain and on behavior. If possible, this genetic parameter should be selected in a way that inferences as to the mechanism of its influence on behavior become feasible. Such genetic variability is provided by the hereditary variants of the normal EEG discovered by earlier work (cf. Vogel, 1970). In the following section, a research program on 298 adult healthy males, most of them soldiers, with various inherited EEG variants is described. Apart from controls with inconspicuous EEGs, this material comprises probands with the following EEG variants: low-voltage (N); low-voltage borderline (NG); monotonous alpha-waves (R); occipital fast alpha-variants (BO); fronto-precentral beta-groups (BG), and diffuse beta-waves (BD). In addition to an EEG examination, the probands were examined with various test methods measuring intelligence (IST; LPS; Raven); working speed and concentration (d-2; KLT); personal attitudes (MMPI; 16PF; RKS); and sensory and motor abilities (flicker fusion; tachistoscopy; reaction time to optic, acoustic and combined stimuli; two-hand dexterity; pursuit rotor; tapping). In a supplementary twin study on 52 male adult twin pairs (26 MZ, 26 DZ), heritabilities were determined for the test scores included in the main study. For most test scores, heritabilities are relatively low; the data are compared with those from the literature. We conclude that the test methods utilized in the main study (on EEG variants) are expected to demonstrate at the most a small to moderate correlation of the EEGs with psychological phenotypes as defined by test examinations, even if a major part of the genetic variability underlying these phenotypes would be due to differences in brain physiology that could be revealed by EEG variation.