Natural categorization through multiple feature learning in pigeons

Recently (Troje, Huber, Loidolt, Aust, & Fieder 1999), we found that pigeons discriminated between large sets of photorealistic frontal images of human faces on the basis of sex. This ability was predominantly based on information contained in the visual texture of those images rather than in their configural properties. The pigeons could learn the distinction even when differences of shape and average intensity were completely removed. Here, we proved more specifically the pigeons' flexibility and efficiency to utilize the class-distinguishing information contained in complex natural classes. First, we used principal component as well as discriminant function analysis in order to determine which aspects of the male and female images could support successful categorization. We then conducted various tests involving systematic transformations and reduction of the feature content to examine whether or not the pigeons' categorization behaviour comes under the control of categorylevel feature dimensions-that is, those stimulus aspects that most accurately divide the stimulus classes into the experimenter-defined categories of 'Male' and 'Female'. Enhanced classification ability in the presence of impoverished test faces that varied only along one of the first three principal components provided evidence that the pigeons used these class-distinguishing stimulus aspects as a basis for generalization to new instances.     

The influence of mood on the search for supporting versus conflicting information: dissonance reduction as a means of mood regulation?

Focusing on similarities between the mood regulation approach and dissonance theory, this article addresses the interplay between dissonance and mood by examining how individuals search for information after making a decision while under the influence of positive versus negative mood. Study 1 suggested that negative mood increased the preference for consonant over dissonant information after decisions, whereas positive mood led to a more balanced information search. In Study 2, participants in negative mood rated consonant information as more pleasant and dissonant information as more annoying than participants in positive mood. In addition, the results suggested that mood regulation processes took place. In Study 3, the findings from Study 1 were replicated with a paradigm in which higher stakes were involved.     

On the association of interparental conflict with developing behavioral inhibition and behavior problems in early childhood.

Associations between interparental conflict and the development of temperament characteristics have seldom been addressed; moreover, studies on the impact of interparental conflict on developing behavior problems in infancy and early childhood are relatively rare. The authors therefore aimed to contribute to the study of these issues. A sample of 64 families was investigated longitudinally. At the infant age of 4 months, negative emotionality was measured with a laboratory routine. When infants were 4, 8, and 12 months old, maternal sensitivity was assessed during home observations, and interparental conflict was measured by means of questionnaires. When infants were 30 months old, behavioral inhibition was measured in 2 laboratory fear episodes, and behavior problems were assessed with a structured clinical interview of the primary caregiver. Interparental conflict and infant negative emotionality were significantly and independently associated with subsequent behavioral inhibition. The association of interparental conflict with behavior problems was moderated by infant negative emotionality. Infants high in negative emotionality developed more serious behavior problems when exposed to high interparental conflict, whereas the association was not significant in infants low in negative emotionality.     

Terrorist threat and employees' perceived ability to cope with organizational change

This study investigated the impact of the perceived threat of terrorism on employees' ability to cope with organizational change as well as potentially underlying psychological mechanisms related to work satisfaction and initiative. Three days after the 2006 thwarted terrorist attacks in the United Kingdom, participants were reminded of terrorist threat (by pictures of terrorist attacks) reported lower levels in their ability to cope with organizational change, as well as lower levels of work satisfaction, than did participants who were not reminded of terrorist threat. Three months later, the same terror salience manipulation had no differential effect on these variables. Mediation analyses revealed that work satisfaction mediated the impact of terror salience on employees' ability to cope with organizational change.     

Personality Traits (“Big Five”) and the Propensity to Political Protest: Alternative Models

In a representative panel study, citizens of Leipzig (East Germany) were interviewed in 1993 and 1996 about their incentives for and participation in political protest activities. Conscientiousness, neuroticism, agreeableness, openness to experience, and extraversion (the Big Five) were measured with 16 bipolar adjectives. The present report supplements a previous work of the authors that drew on the theories of rational choice and collective action and conceived of incentives as proximal causes and personality dispositions as distant causes of political protest. Based on structural equation modelling (SEM), the present article deals with the respondents' recurrent reports on protest incentives and protest acts as indicators of the latent construct protest propensity that is according to the predictions directly influenced by openness to experience (O+), agreeableness (A?), neuroticism (N?), and reciprocity orientation (N*E+) with 35% explained variance.     

Topografie der Jugenddelinquenz

The article shows that the registered juvenile delinquency has decreased in recent years. Serious violent crime partially exists, but this is only a small part of the overall juvenile delinquency. Forms of appearance of these violent crimes are outlined. With the help of a dark field study it is illustrated that there is a great variety of delinquency among young people. There are young people showing mostly law-abiding behavior, infrequent offenders and a group with a significant burden of crimes.     

Entwicklung und Stand des psychiatrischen Maßregelvollzugs (§ 63 StGB)

Psychiatric forensic commitment is at the interface between psychiatry and criminal justice. Both fields are subject to societal and political influences, which are not to be underestimated and have undergone many changes since the introduction of the catalogue of penal measures in 1933. This article provides a summarizing overview of the development of psychiatric penal measures in the 8 decades since its inception. The various developmental phases are chonologically presented and analyzed, in some cases with reference to the international situation. The main transition is the change from custodial detention up to modern treatment enforcement, even if many different factors influence the certainly to be strived for further development. Finally, the complex topics of “forensic psychiatry and the public” as well as the influence of the media on this aspect are briefly discussed.     

The Accuracy of Retrospective Recall of Childhood ADHD: Results from a Longitudinal Study

Attention-deficit/hyperactivity disorder (ADHD) is a childhood-onset condition that may continue into adulthood. When assessing adult patients, clinicians usually rely on retrospective reports of childhood symptoms to evaluate the age-of-onset criterion. Since inaccurate symptom recall may impede the diagnosis and treatment of ADHD, knowledge about the factors influencing retrospective reports is needed. This longitudinal study investigated (a) the accuracy of retrospective symptom ratings by adult participants with a childhood diagnosis of ADHD (self-ratings) and parents or significant others (proxy ratings), and (b) the influence of current ADHD symptom severity and ADHD-associated impairments on retrospective symptom ratings. Participants (N =?55) were members of the Cologne Adaptive Multimodal Treatment (CAMT) study who had been referred and treated for ADHD in childhood and were reassessed in adulthood (average age 27 years). Participants’ retrospective self-ratings were substantially lower than, and did not correlate with, parents’ ADHD symptom ratings provided at study entry, while retrospective symptom ratings provided by proxy respondents correlated moderately with parents’ childhood ratings. In addition, participants were more likely to underreport childhood symptoms (79%) and more frequently denied the presence of three or more childhood symptoms (17%) compared to proxy respondents (65% underreporting, 10% false-negative recall). Proxy respondents’ symptom recall was best predicted by childhood ADHD, while participants’ symptom recall was best predicted by current ADHD symptom severity. ADHD-associated impairments were not correlated with symptom recall after controlling for childhood ADHD. Together, these findings suggest a recall bias in adult patients and question the validity of retrospective reports, even in clinical samples.