Investigating the dopaminergic basis of extraversion in humans: A multilevel approach

A recent theory suggests that the agency facet of Extraversion (E) is based on brain dopamine (DA). The paucity of human data relevant to this model is probably due to the lack of widely accessible noninvasive psychophysiological indices and well-established behavioral measures sensitive to both E and manipulations of DA activity. Aiming to identify such measures, the authors assessed the electroencephalogram and n-back task performance in groups of introverts and extraverts after administration of either placebo or a selective DA D2 receptor antagonist. As predicted, the antagonist's effects on n-back reaction time measures and frontal versus parietal electroencephalogram theta activity were strongly and specifically modulated by E. New research avenues and theoretical extensions suggested by these results are discussed.     

Somatisierung

Zusammenfassung Somatisierung meint die Erfahrung und den Bericht von k?rperlichen Beschwerden, für die kein hinreichender medizinischer Befund vorliegt, verbunden mit einem hohen Ausma? von organ-medizinischer Hilfesuche. Gegenüber früheren Definitionen, die st?rker auf psychosoziale Faktoren bei der Somatisierung abheben, wird gegenw?rtig eine ausschlie?lich beschreibende Begriffsfestlegung bevorzugt. Somatisierung liegt als Normenvariante bis zur schweren pathologischen Auspr?gung vor. Die ICD-10 fa?t sehr heterogene Krankheitsbilder von Somatisierung in der Klasse der somatoformen St?rungen zusammen. Fraglich ist, ob Somatisierung eher als Proze? denn als diskrete Krankheitseinheit zu konzeptualisieren ist. Somatisierung enth?lt drei Komponenten: Auf der Wahrnehmungsebene erh?hte Sensibilit?t gegenüber K?rpersensationen (“somatosensorische Amplifikation”), auf der Erlebensebene negative Affekte in Form von psychischem und somatischen Distre?erleben, auf der Verhaltensebene inad?quate Inanspruchnahme der Gesundheitsressourcen (“abnormes Krankheitsverhalten”). Trotz z. T. vielversprechender Behandlungsvorschl?te unter verhaltenstherapeutischer, psychodynamischer und psychoedukativer Orientierung erscheint die Prognose von Somatisierung bisher wenig günstig. Es gibt Hinweise, da? der Sicherung der therapeutischen Beziehung besondere Bedeutung für den Behandlungserfolg zukommt.      

Ein logisch-pragmatisches modell von deduktiv-nomologischer erkl?rung (systematisierung)

The present paper first shows that the validity of deductive-nomological (D-N) explanations (systematizations) depends in general on the interpretation context of the predicates involved in the explanation. Therefore, no logical-semantical model can be adequate. This problem is solved by relativisation of the validity criteria on both the confirmation context and the definition context of the premisses. Based upon this, a logical-pragmatical model of D-N explanation is developed. Thereby, especially explanations of laws and global explanations are taken into consideration, since these can be regarded as prototypes of scientific explanation.

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Diese Arbeit basiert auf einer Dissertation. Prof. Haller, dem Dissertationsleiter, sowie Prof. Lehrer und Prof. Körner seien für viele Anregungen gedankt.     

Stability of aggression among adolescents over time: A south African study

In a study spanning 5 years, data were collected on the aggressiveness of over 1,700 male and female subjects. Subjects who were the more aggressive grade 8 (standard 6) pupils at the beginning of the study were discovered to be the more aggressive grade 12 (standard 10) pupils. It is concluded that, whatever its causes, aggression can be viewed as a persistent trait that may be influenced by situational variables but reveals substantial consistency over time. The findings of studies by Huesmann and Eron in the United States as well as Olweus in Scandinavia were thus supported in this South African investigation.     

When can we trust theF-approximation of the box-test?

Consider a multivariate context withp variates andk independent samples, each of sizen. To test equality of thek population covariance matrices, the likelihood ratio test is commonly employed. Box'sF-approximation to the null distribution of the test statistic can be used to computep-values, if sample sizes are not too small. It is suggested to regard theF-approximation as accurate if the sample sizesn are greater than or equal to 1+0.0613p ²+2.7265p-1.4182p ^0.5+0.235p ^1.4* In (k), for 5p30,k20.This research was supported by the Deutsche Forschungsgemeinschaft through Ste 405/2-1.     

A model for science kinematics

A comprehensive model for describing various forms of developments in science is defined in precise, set-theoretic terms, and in the spirit of the structuralist approach in the philosophy of science. The model emends previous accounts in centering on single systems in a homogenous way, eliminating notions which essentially refer to sets of systems. This is achieved by eliminating the distinction between theoretical and non-theoretical terms as a primitive, and by introducing the notion of intended links. The force of the model is demonstrated by formally incorporating many of the important, precise meta-theoretic concepts occurring in the literature.This paper was written under DFG project Ba 678/3-2.     

Evaluation of human consciousness level by means of “automated fluctuation analysis” of high frequency electroencephalogram fitted by double Lorentzians

Since Berger’s discovery of the electroencephalogram (EEG), its analysis has been generally restricted to the visual range (upmost 100Hz) and has ignored higher frequency components. One reason should be that there are no reliable methods to distinguish the brain potentials from muscle activity. We have introduced fluctuation analysis, which is popular method especially in the field of basic physiology to clinical electrophysiology. In our previous study, it was declared that power spectral density (PSD) of human high frequency EEG was composed of double Lorentzians and vanished into white level within 1kHz. Then the purpose of this study is to elucidate the “Automated Fluctuation Analysis,” which enables us to evaluate these higher frequency components and its physiological meaning especially focused on conscious level from wakefulness to sleep stage 1. Seventy-four scalp recording EEGs in twenty normal subjects were studied. In short, “Automated Fluctuation Analysis” is made of three steps: amplification of EEG signal, A/D conversion and Fast Fourier Transform by signal processor and extraction of Lorentzian parameters. PSD of high frequency EEG was displayed on log-log graph and the algorithm fit to the following Lorentzian formula were mathematically based on Brown & Dennis. S(f)=S1/ [1+(f/fc₁)²] + S2/ [1+(f/fc₂)²], where S(f) is PSD (μ V²/Hz) at each frequency (f;Hz), S1 and S2 are the plateau level or zero-frequency power of the initial and second Lorentz, and fc₁ and fc₂ are the corner or half-power frequency of the initial and second Lorentz, respectively. As results, during wakefulness the PSD of high frequency EEG activity was composed of double Lorentzian fluctuations and the power distribution of S1 value in topographical display was frontal dominant. This pattern of S1 value disappeared and S2 value became lower during sleepiness and the second Lorentz disappeared during sleep.     

Hermeneutische und hypothetisch-deduktive Methode

Journal for General Philosophy of Science - Der Wissenschaftsbegriff kann nicht einseitig auf den Begriff von „science“ eingeengt werden. Eine strenge Scheidung in...