Early life exposure to cortisol in zebrafish (Danio rerio): similarities and differences in behaviour and physiology between larvae of the AB and TL strains.

Maternal stress and early life stress affect development. Zebrafish (Danio rerio) are ideally suited to study this, as embryos develop externally into free-feeding larvae. The objective of this study was therefore to assess the effects of increased levels of cortisol, mimicking thereby maternal stress, on larval physiology and behaviour.

Transient Prepubertal Mifepristone Treatment Normalizes Deficits in Contextual Memory and Neuronal Activity of Adult Male Rats Exposed to Maternal Deprivation.

Early life adversity is a well-known risk factor for behavioral dysfunction later in life, including the formation of contextual memory; it is also (transiently) accompanied by hyperactivity of the stress system. We tested whether mifepristone (MIF) treatment, which among other things blocks glucocorticoid receptors (GRs), during the prepubertal period [postnatal days (PND)26-PND28] normalizes memory deficits in adult male rats exposed to 24-h maternal deprivation (MD) at PND3. MD reduced body weight gain and increased basal corticosterone (CORT) levels during the PND26, but not in adulthood.

Light regimes differentially affect baseline transcript abundance of stress-axis and (neuro)development-related genes in zebrafish (, Hamilton 1822) AB and TL larvae.

Many strains of zebrafish () are readily available. Earlier we observed differences between AB and Tupfel long-fin (TL) larvae regarding baseline hypothalamus-pituitary-interrenal (HPI) axis activity and (neuro)development. Light regimes, i.

Further characterisation of differences between TL and AB zebrafish (Danio rerio): Gene expression, physiology and behaviour at day 5 of the larval stage.

Zebrafish (Danio rerio) have become popular as model organism in research. Many strains are readily available, which not only differ morphologically, but also genetically, physiologically and behaviourally. Here, we focus on the AB and Tupfel long-fin (TL) strain for which we have previously shown that adults differ in baseline hypothalamus-pituitary-interrenal (HPI)-axis activity (AB higher than TL) affecting inhibitory avoidance behaviour (absent in AB).

Sex differences in risk-taking and associative learning in rats.

In many species, males tend to have lower parental investment than females and greater variance in their reproductive success. Males might therefore be expected to adopt more high-risk, high-return behaviours than females. Next to risk-taking behaviour itself, sexes might also differ in how they respond to information and learn new associations owing to the fundamental link of these cognitive processes with the risk-reward axis.

Providing a food reward reduces inhibitory avoidance learning in zebrafish.

As shown in male rats, prior history of subjects changes behavioural and stress-responses to challenges: a two-week history of exposure to rewards at fixed intervals led to slightly, but consistently, lower physiological stress-responses and anxiety-like behaviour. Here, we tested whether similar effects are present in zebrafish (Danio rerio). After two weeks of providing Artemia (brine shrimp; Artemia salina) as food reward or flake food (Tetramin) as control at fixed intervals, zebrafish were exposed to a fear-avoidance learning task using an inhibitory avoidance protocol.

The effects of environmental enrichment and age-related differences on inhibitory avoidance in zebrafish (Danio rerio Hamilton).

The inhibitory avoidance paradigm allows the study of mechanisms underlying learning and memory formation in zebrafish (Danio rerio Hamilton). For zebrafish, the physiology and behavior associated with this paradigm are as yet poorly understood. We therefore assessed the effects of environmental enrichment and fish age on inhibitory avoidance learning.

The dorsal striatum and ventral striatum play different roles in the programming of social behaviour: a tribute to Lex Cools.

Early work by Lex Cools suggested that the caudate nucleus (dorsal striatum) plays a role in programming social behaviour: enhanced activity in the caudate nucleus increased the extent to which ongoing behaviour is controlled by the individual's own behaviour (internal control) rather than by that of its partners (external control). Interestingly, later studies by others have indicated that the ventral striatum plays a role in external rather than internal control. Here, I discuss the role of these different striatal areas - and the emotional (ventral striatum) and cognitive control (dorsal striatum) system in which they are embedded - in the organization of social behaviour in the context of locus of control.

Unpredictable chronic stress decreases inhibitory avoidance learning in Tuebingen long-fin zebrafish: stronger effects in the resting phase than in the active phase.

Zebrafish (Danio rerio Hamilton) are increasingly used as a model to study the effects of chronic stress on brain and behaviour. In rodents, unpredictable chronic stress (UCS) has a stronger effect on physiology and behaviour during the active phase than during the resting phase. Here, we applied UCS during the daytime (active phase) for 7 and 14 days or during the night-time (resting phase) for 7 nights in an in-house-reared Tuebingen long-fin (TLF) zebrafish strain.

Inhibitory avoidance learning in zebrafish (Danio rerio): effects of shock intensity and unraveling differences in task performance.

The zebrafish (Danio rerio) is increasingly used as a model in neurobehavioral and neuroendocrine studies. The inhibitory avoidance paradigm has been proposed as tool to study mechanisms underlying learning and memory in zebrafish. In this paradigm subjects receive a shock after entering the black compartment of a black-white box.

Corticosterone and decision-making in male Wistar rats: the effect of corticosterone application in the infralimbic and orbitofrontal cortex.

Corticosteroid hormones, released after stress, are known to influence neuronal activity and produce a wide range of effects upon the brain. They affect cognitive tasks including decision-making. Recently it was shown that systemic injections of corticosterone (CORT) disrupt reward-based decision-making in rats when tested in a rat model of the Iowa Gambling Task (rIGT), i.

Risk-taking and pathological gambling behavior in Huntington's disease.

Huntington's disease (HD) is a genetic, neurodegenerative disorder, which specifically affects striatal neurons of the indirect pathway, resulting in a progressive decline in muscle coordination and loss of emotional and cognitive control. Interestingly, predisposition to pathological gambling and other addictions involves disturbances in the same cortico-striatal circuits that are affected in HD, and display similar disinhibition-related symptoms, including changed sensitivity to punishments and rewards, impulsivity, and inability to consider long-term advantages over short-term rewards. Both HD patients and pathological gamblers also show similar performance deficits on risky decision-making tasks, such as the Iowa Gambling Task (IGT).

A rodent version of the Iowa Gambling Task: 7 years of progress.

In the Iowa Gambling Task (IGT) subjects need to find a way to earn money in a context of variable wins and losses, conflicting short-term and long-term pay-off, and uncertainty of outcomes. In 2006, we published the first rodent version of the IGT (r-IGT; Behavior Research Methods 38, 470-478). Here, we discuss emerging ideas on the involvement of different prefrontal-striatal networks in task-progression in the r-IGT, as revealed by our studies thus far.

Effects of Pro-Tex on zebrafish (Danio rerio) larvae, adult common carp (Cyprinus carpio) and adult yellowtail kingfish (Seriola lalandi).

Aquaculture practices bring several stressful events to fish. Stressors not only activate the hypothalamus-pituitary-interrenal-axis, but also evoke cellular stress responses. Up-regulation of heat shock proteins (HSPs) is among the best studied mechanisms of the cellular stress response.

Salivary cortisol and alpha-amylase levels during an assessment procedure correlate differently with risk-taking measures in male and female police recruits.

Recent laboratory studies have shown that men display more risk-taking behavior in decision-making tasks following stress, whilst women are more risk-aversive or become more task-focused. In addition, these studies have shown that sex differences are related to levels of the stress hormone cortisol (indicative of activation of the hypothalamus-pituitary-adrenocortical-axis): the higher the levels of cortisol the more risk-taking behavior is shown by men, whereas women generally display more risk-aversive or task-focused behavior following higher levels of cortisol. Here, we assessed whether such relationships hold outside the laboratory, correlating levels of cortisol obtained during a job-related assessment procedure with decision-making parameters in the Cambridge Gambling Task (CGT) in male and female police recruits.

Cross-species approaches to pathological gambling: a review targeting sex differences, adolescent vulnerability and ecological validity of research tools.

Decision-making plays a pivotal role in daily life as impairments in processes underlying decision-making often lead to an inability to make profitable long-term decisions. As a case in point, pathological gamblers continue gambling despite the fact that this disrupts their personal, professional or financial life. The prevalence of pathological gambling will likely increase in the coming years due to expanding possibilities of on-line gambling through the Internet and increasing liberal attitudes towards gambling.

Social modulation of decision-making: a cross-species review.

Taking decisions plays a pivotal role in daily life and comprises a complex process of assessing and weighing short-term and long-term costs and benefits of competing actions. Decision-making has been shown to be affected by factors such as sex, age, genotype, and personality. Importantly, also the social environment affects decisions, both via social interactions (e.

Stress in African catfish (Clarias gariepinus) following overland transportation.

Of the many stressors in aquaculture, transportation of fish has remained poorly studied. The objective of this study was therefore to assess the effects of a (simulated) commercial transportation on stress physiology of market-size African catfish (Clarias gariepinus). Catfish weighing approximately 1.

Immunization with DAT fragments is associated with long-term striatal impairment, hyperactivity and reduced cognitive flexibility in mice.

Background: Possible interactions between nervous and immune systems in neuro-psychiatric disorders remain elusive. Levels of brain dopamine transporter (DAT) have been implicated in several impulse-control disorders, like attention deficit / hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD). Here, we assessed the interplay between DAT auto-immunity and behavioural / neurochemical phenotype.

A critical review of sex differences in decision-making tasks: focus on the Iowa Gambling Task.

It has been observed that men and women show performance differences in the Iowa Gambling Task (IGT), a task of decision-making in which subjects through exploration learn to differentiate long-term advantageous from long-term disadvantageous decks of cards: men choose more cards from the long-term advantageous decks than women within the standard number of 100 trials. Here, we aim at discussing psychological mechanisms and neurobiological substrates underlying sex differences in IGT-like decision-making. Our review suggests that women focus on both win-loss frequencies and long-term pay-off of decks, while men focus on long-term pay-off.