Atypical birdsong and artificial languages provide insights into how communication systems are shaped by learning, use and transmission

In this article, I argue that a comparative approach focusing on the cognitive capacities and behavioral mechanisms that underlie vocal learning in songbirds and humans can provide valuable insights into the evolutionary origins of language. The experimental approaches I discuss use abnormal song and atypical linguistic input to study the processes of individual learning, social interaction, and cultural transmission. Atypical input places increased learning and communicative pressure on learners, so exploring how they respond to this type of input provides a particularly clear picture of the biases and constraints at work during learning and use. Furthermore, simulating the cultural transmission of these unnatural communication systems in the laboratory informs us about how learning and social biases influence the structure of communication systems in the long run. Findings based on these methods suggest fundamental similarities in the basic social–cognitive mechanisms underlying vocal learning in birds and humans, and continuing research promises insights into the uniquely human mechanisms and into how human cognition and social behavior interact, and ultimately impact on the evolution of language

An evolutionary perspective on the co-occurrence of social anxiety disorder and alcohol use disorder

Social Anxiety Disorder (SAD) commonly co-occurs with, and often precedes, Alcohol Use Disorder (AUD). In this paper, we address the relationship between SAD and AUD by considering how natural selection left socially anxious individuals vulnerable to alcohol use, and by addressing the underlying mechanisms. We review research suggesting that social anxiety has evolved for the regulation of behaviors involved in reducing the likelihood or consequences of threats to social status. The management of potential threats to social standing is important considering that these threats can result in reduced cooperation or ostracism – and therefore to reduced access to coalitional partners, resources or mates. Alcohol exerts effects upon evolutionarily conserved emotion circuits, and can down-regulate or block anxiety (or may be expected to do so). As such, the ingestion of alcohol can artificially signal the absence or successful management of social threats. In turn, alcohol use may be reinforced in socially anxious people because of this reduction in subjective malaise, and because it facilitates social behaviors – particularly in individuals for whom the persistent avoidance of social situations poses its own threat (i.e., difficulty finding mates). Although the frequent co-occurrence of SAD and AUD is associated with poorer treatment outcomes than either condition alone, a richer understanding of the biological and psychosocial drives underlying susceptibility to alcohol use among socially anxious individuals may improve the efficacy of therapeutic interventions aimed at preventing or treating this comorbidity

Stufenweise Entwicklung einer Drogenabhaengigkeit im Tiermodell: Kausalanalyse und Eingriffsmoeglichkeiten Abschlussbericht

The neurobiological and behavioural basis of addictive disorders are, at present, poorly understood. Consequently, current addition therapies are not 'causal' but rather symptomatic. We have established an animal model that enables the induction of addictive behaviour in rats equivalent to that of human beings (a not spontaneously reversible loss of control over drug taking). The model includes several months of access to drug-containing drinking fluids in a free-choice paradigm, a period of forced abstinence, and a retest with a check for loss of control. By means of this procedure we investigated the stages of a development of drug-addiction, in particular the 'point of no return' (the step toward a loss of control) of opioid self administration could be fixed to a period of some weeks. The urge for the drug changes substantially in the course of this step, a novel, compulsive component ('craving') appears. 'Gateway drugs' or concomitant use of more than one agent change the mode of controlled consumption without affecting the point of no return. On the molecular level, we found both genetic factors of vulnerability and addiction-related changes in the dopaminergic signaltransduction of subcortical brain areas. These long-term persisting changes might - together first attempts to revert the loss of control - contribute to a development of a causal concept of an addiction therapy. (orig.)SIGLEAvailable from TIB Hannover: DtF QN1(62,5) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Light‐Activation of DNA‐Methyltransferases

5-Methylcytosine (5mC), the central epigenetic mark of mammalian DNA, plays fundamental roles in chromatin regulation. 5mC is written onto genomes by DNA methyltransferases (DNMT), and perturbation of this process is an early event in carcinogenesis. However, studying 5mC functions is limited by the inability to control individual DNMTs with spatiotemporal resolution in vivo. We report light-control of DNMT catalysis by genetically encoding a photocaged cysteine as a catalytic residue. This enables translation of inactive DNMTs, their rapid activation by light-decaging, and subsequent monitoring of de novo DNA methylation. We provide insights into how cancer-related DNMT mutations alter de novo methylation in vivo, and demonstrate local and tuneable cytosine methylation by light-controlled DNMTs fused to a programmable transcription activator-like effector domain targeting pericentromeric satellite-3 DNA. We further study early events of transcriptome alterations upon DNMT-catalyzed cytosine methylation. Our study sets a basis to dissect the order and kinetics of diverse chromatin-associated events triggered by normal and aberrant DNA methylation

Plastische Veraenderungen von synaptischer Transmission und Verhalten bei Ratten und Maeusen als Auswirkung sozialer Isolation Schlussbericht

Available from TIB Hannover: F96B1648+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman