Short- and long-term behavioral analysis of social interaction, ultrasonic vocalizations and social motivation in a chronic phencyclidine model.

Phencyclidine (PCP) has been suggested to induce symptoms of schizophrenia. However, animal models using PCP administration have produced ambiguous results thus far. It seems that acute effects are similar to symptoms of schizophrenia, however, it is not clear if PCP can induce permanent behavioral changes that reflect schizophrenic-like symptoms.

Novel approach to automatically classify rat social behavior using a video tracking system.

Background: In the past, studies in behavioral neuroscience and drug development have relied on simple and quick readout parameters of animal behavior to assess treatment efficacy or to understand underlying brain mechanisms. The predominant use of classical behavioral tests has been repeatedly criticized during the last decades because of their poor reproducibility, poor translational value and the limited explanatory power in functional terms.

New Method: We present a new method to monitor social behavior of rats using automated video tracking.

Male long-tailed macaques (Macaca fascicularis) understand the target of facial threat.

The cognitive demands of group living have resulted in the development of social competences in a wide range of animal species. Primates are well aware of the complex social structure within their group and infer information about social status by observing interactions of others. A capacity used to infer this information, Visual Perspective Taking (VPT), is present in apes and in monkeys.

Intermediate-term emotional bookkeeping is necessary for long-term reciprocal grooming partner preferences in an agent-based model of macaque groups.

Whether and how primates are able to maintain long-term affiliative relationships is still under debate. Emotional bookkeeping (EB), the partner-specific accumulation of emotional responses to earlier interactions, is a candidate mechanism that does not require high cognitive abilities. EB is difficult to study in real animals, due to the complexity of primate social life.

Ethological concepts enhance the translational value of animal models.

The translational value of animal models is an issue of ongoing discussion. We argue that 'Refinement' of animal experiments is needed and this can be achieved by exploiting an ethological approach when setting up and conducting experiments. Ethology aims to assess the functional meaning of behavioral changes, due to experimental manipulation or treatment, in animal models.

Emotional bookkeeping and high partner selectivity are necessary for the emergence of partner-specific reciprocal affiliation in an agent-based model of primate groups.

Primate affiliative relationships are differentiated, individual-specific and often reciprocal. However, the required cognitive abilities are still under debate. Recently, we introduced the EMO-model, in which two emotional dimensions regulate social behaviour: anxiety-FEAR and satisfaction-LIKE.

Anticipatory and foraging behaviors in response to palatable food reward in chickens: effects of dopamine D2 receptor blockade and domestication.

Behaviors associated with anticipation and search for palatable food may provide information about dopaminergic reward processes and positive motivational affect in animals. The overall aim was to investigate the involvement of dopamine signaling in the regulation of cue-induced anticipation and search for palatable food reward in chicken, and whether domestication has affected expression of reward-related behaviors. The specific aims were to describe effects of mealworms (palatable food for hens) and haloperidol (a dopamine D2 antagonist) on foraging behaviors and cue-induced anticipatory behaviors in Red Junglefowl (RJF; the wild ancestor of modern laying hens) and a white layer hybrid (LSL).

Reproducibility and relevance of future behavioral sciences should benefit from a cross fertilization of past recommendations and today's technology: "Back to the future".

Thanks to the discovery of novel technologies and sophisticated analysis tools we can now 'see' molecules, genes and even patterns of gene expression, which have resulted in major advances in many areas of biology. Recently, similar technologies have been developed for behavioral studies. However, the wide implementation of such technological progress in behavioral research remains behind, as if there are inhibiting factors for accepting and adopting available innovations.

The EMO-model: an agent-based model of primate social behavior regulated by two emotional dimensions, anxiety-FEAR and satisfaction-LIKE.

Agent-based models provide a promising tool to investigate the relationship between individuals' behavior and emerging group-level patterns. An individual's behavior may be regulated by its emotional state and its interaction history with specific individuals. Emotional bookkeeping is a candidate mechanism to keep track of received benefits from specific individuals without requiring high cognitive abilities.

Orangutan (Pongo spp.) whistling and implications for the emergence of an open-ended call repertoire: a replication and extension.

One of the most apparent discontinuities between non-human primate (primate) call communication and human speech concerns repertoire size. The former is essentially fixed to a limited number of innate calls, while the latter essentially consists of numerous learned components. Consequently, primates are thought to lack laryngeal control required to produce learned voiced calls.

Melanocortin MC(4) receptor-mediated feeding and grooming in rodents.

Decades ago it was recognized that the pharmacological profile of melanocortin ligands that stimulated grooming behavior in rats was strikingly similar to that of Xenopus laevis melanophore pigment dispersion. After cloning of the melanocortin MC1 receptor, expressed in melanocytes, and the melanocortin MC4 receptor, expressed mainly in brain, the pharmacological profiles of these receptors appeared to be very similar and it was demonstrated that these receptors mediate melanocortin-induced pigmentation and grooming respectively. Grooming is a low priority behavior that is concerned with care of body surface.

Population-specific use of the same tool-assisted alarm call between two wild orangutan populations (Pongo pygmaeus wurmbii) indicates functional arbitrariness [corrected].

Arbitrariness is an elementary feature of human language, yet seldom an object of comparative inquiry. While arbitrary signals for the same function are relatively frequent between animal populations across taxa, the same signal with arbitrary functions is rare and it remains unknown whether, in parallel with human speech, it may involve call production in animals. To investigate this question, we examined a particular orangutan alarm call - the kiss-squeak - and two variants - hand and leaf kiss-squeaks.

An automated system for the recognition of various specific rat behaviours.

The automated measurement of rodent behaviour is crucial to advance research in neuroscience and pharmacology. Rats and mice are used as models for human diseases; their behaviour is studied to discover and develop new drugs for psychiatric and neurological disorders and to establish the effect of genetic variation on behavioural changes. Such behaviour is primarily labelled by humans.

Look before you leap - individual variation in social vigilance shapes socio-spatial group properties in an agent-based model.

Next to predator detection, primate vigilance also serves to keep track of relevant conspecifics. The degree of vigilance towards group members often reflects the dominance rank of an individual: subordinates pay attention to dominants. Although it has been suggested that subordinates' vigilance may result in spatial centrality of dominants, this has not been addressed in either empirical or modeling studies.

Take it or leave it: transport of tools for future use by long-tailed macaques (Macaca fascicularis).

Future planning has previously been considered unique to humans. However, certain animals can foresee some of their future needs. We tested long-tailed macaques (Macaca fascicularis) ability to transport and after a delay use a rake, in two experiments.

Male Mating Tactics in Captive Rhesus Macaques (Macaca mulatta): The Influence of Dominance, Markets, and Relationship Quality.

Male mating success in a multimale-multifemale group can depend on several variables: body condition, dominance, coalitions, "friendship," or an exchange of services for mating access. Exchange patterns may also be determined by market effects or social relationships. We studied the mating tactics of males in a captive, multimale-multifemale group of rhesus macaques and the resulting patterns of mating and paternity to determine the influence of dominance rank, mating markets, and relationship quality on their mating tactics.

Better safe than sorry--socio-spatial group structure emerges from individual variation in fleeing, avoidance or velocity in an agent-based model.

In group-living animals, such as primates, the average spatial group structure often reflects the dominance hierarchy, with central dominants and peripheral subordinates. This central-peripheral group structure can arise by self-organization as a result of subordinates fleeing from dominants after losing a fight. However, in real primates, subordinates often avoid interactions with potentially aggressive group members, thereby preventing aggression and subsequent fleeing.

Inequity aversion in relation to effort and relationship quality in long-tailed Macaques (Macaca fascicularis).

Social animals may employ evolved implicit rules to maintain a balance between cooperation and competition. Inequity aversion (IA), the aversive reaction to an unequal distribution of resources, is considered such a rule to avoid exploitation between cooperating individuals. Recent studies have revealed the presence of IA in several nonhuman species.

Benefiting friends or dominants: prosocial choices mainly depend on rank position in long-tailed macaques (Macaca fascicularis).

Long-term observational studies in a number of animal species suggest that exchange patterns of social acts depend on long-term emotional bonds. Therefore, it is expected that the frequency of prosocial behavior will depend on the strength of such a bond. In this study we tested whether variation in relationship quality among unrelated individuals, i.

Chimpanzees (Pan troglodytes) fail a what-where-when task but find rewards by using a location-based association strategy.

Recollecting the what-where-when of an episode, or episodic-like memory, has been established in corvids and rodents. In humans, a linkage between remembering the past and imagining the future has been recognised. While chimpanzees can plan for the future, their episodic-like memory has hardly been investigated.

Effects of haloperidol, a dopamine D2-like receptor antagonist, on reward-related behaviors in laying hens.

In order to investigate the involvement of dopaminergic transmission in the regulation of reward-related behaviors in laying hens, the effects of systemic injections of dopamine D2-like receptor antagonist haloperidol (0.3, 0.5, 1.

Long-lasting modulation of synaptic plasticity in rat hippocampus after early-life complex febrile seizures.

A small fraction of children with febrile seizures appears to develop cognitive impairments. Recent studies in a rat model of hyperthermia-induced febrile seizures indicate that prolonged febrile seizures early in life have long-lasting effects on the hippocampus and induce cognitive deficits. However, data on network plasticity and the nature of cognitive deficits are conflicting.

Generous leaders and selfish underdogs: pro-sociality in despotic macaques.

Actively granting food to a companion is called pro-social behavior and is considered to be part of altruism. Recent findings show that some non-human primates behave pro-socially. However, pro-social behavior is not expected in despotic species, since the steep dominance hierarchy will hamper pro-sociality.

Announced reward counteracts the effects of chronic social stress on anticipatory behavior and hippocampal synaptic plasticity in rats.

Chronic stress causes insensitivity to rewards (anhedonia) in rats, reflected by the absence of anticipatory behavior for a sucrose-reward, which can be reversed by antidepressant treatment or repeated announced transfer to an enriched cage. It was, however, not clear whether the highly rewarding properties of the enriched cage alone caused this reversal or whether the anticipation of this reward as such had an additional effect. Therefore, the present study compared the consequences of the announcement of a reward to the mere effect of a reward alone with respect to their efficacy to counteract the consequences of chronic stress.

Home seeking behavior in rat pups: Attachment vs. kin selection, oxytocin vs. vasopressin.

We are interested in the rat as an animal model for infant-mother attachment. In the first experiment we tried to distinguish between a preference for familiar animals (attachment theory) and a preference for genetically related animals (kin selection theory) with the use of an early cross-fostering procedure. Genetic relationships did not influence preferences in cross-fostered pups on postnatal day 17, only familiarity did.