The formation of memories is a complex, multi-scale phenomenon, especially when it involves integration of information from various brain systems. We have investigated the differences between a novel and consolidated association of spatial cues and amphetamine administration, using an in situ hybridisation method to track the short-term dynamics during the recall testing. We have found that remote recall group involves smaller, but more consolidated groups of neurons, which is consistent with their specialisation. By employing machine learning analysis, we have shown this pattern is especially pronounced in the VTA; furthermore, we also uncovered significant activity patterns in retrosplenial and prefrontal cortices, as well as in the DG and CA3 subfields of the hippocampus. The behavioural propensity towards the associated localisation appears to be driven by the nucleus accumbens, however, further modulated by a trio of the amygdala, VTA and hippocampus, as the trained association is confronted with test experience. Moreover, chemogenetic analysis revealed central amygdala as critical for linking appetitive emotional states with spatial contexts. These results show that memory mechanisms must be modelled considering individual differences in motivation, as well as covering dynamics of the process.
- MeSH
- amfetamin farmakologie MeSH
- amygdala fyziologie metabolismus MeSH
- hipokampus fyziologie metabolismus MeSH
- konsolidace paměti * fyziologie účinky léků MeSH
- krysa rodu Rattus MeSH
- mozek fyziologie MeSH
- neurony fyziologie MeSH
- nucleus accumbens fyziologie MeSH
- odměna MeSH
- paměť fyziologie MeSH
- podněty MeSH
- prefrontální mozková kůra fyziologie MeSH
- rozpomínání * fyziologie účinky léků MeSH
- strojové učení MeSH
- tegmentum mesencephali - area ventralis fyziologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- amfetamin MeSH
Effort-based decision-making is particularly relevant to psychiatric conditions where motivation deficits are prominent features. Despite its clinical significance, the neurochemical mechanisms of this cognitive process remain unclarified. This study explores the impact of serotonin synthesis inhibition (PCPA) and modulation of serotonin release and 5-HT1A receptor agonism (8-OH-DPAT) on effort-based decision-making in rats. Adult male rats were trained in a modified T-maze task where they could obtain a high reward for climbing a mesh barrier or a low reward for no extra effort. Following training, rats received either acute 8-OH-DPAT treatment or subchronic PCPA treatment and were tested on their choices between high- and low-effort arms. The goal-arm choices and goal-arm entrance latencies were recorded. Next, homovanillic acid and 5-hydroxyindoleacetic acid, metabolites of dopamine and serotonin, respectively, were quantified in the rats' prefrontal cortex, striatum, and hippocampus. 8-OH-DPAT significantly increased low-effort, low-reward choices and increased goal-arm latency. In contrast, PCPA treatment did not affect these measures. Both PCPA and 8-OH-DPAT significantly decreased 5-hydroxyindoleacetic acid levels in the prefrontal cortex and the hippocampus. 8-OH-DPAT treatment was also associated with decreased homovanillic acid levels in the hippocampus. Our findings suggest that the overall reduction of serotonin levels alone does not affect effort-based decision-making and highlights the possible role of the hippocampus and the 5-HT1A receptor in this cognitive process.
- MeSH
- 8-hydroxy-2-(di-N-propylamino)tetralin * farmakologie MeSH
- agonisté serotoninového receptoru 5-HT1 farmakologie MeSH
- bludiště - učení účinky léků fyziologie MeSH
- chování zvířat účinky léků MeSH
- krysa rodu Rattus MeSH
- odměna MeSH
- potkani Sprague-Dawley MeSH
- rozhodování * fyziologie účinky léků MeSH
- serotonin * metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- 8-hydroxy-2-(di-N-propylamino)tetralin * MeSH
- agonisté serotoninového receptoru 5-HT1 MeSH
- serotonin * MeSH
There are currently no pharmacological treatments for cocaine use disorder. Recently there has been a great deal of interest in the potential of psychedelic drugs such as psilocybin to treat psychiatric disorders. Human studies have indicated that a single administration of psilocybin can have long-lasting effects. Few preclinical studies have examined a role for psilocybin in addiction models. The goal of the current study was to determine whether psilocybin would enhance extinction following cocaine self-administration in male and female mice and rats and thus result in an attenuation of cue-induced drug-seeking. In experiments in mice, 16 female and 19 male mice underwent 8d of cocaine self-administration (0.5 mg/kg/infusion) and extinction training. Immediately following extinction trials, mice were injected with vehicle or 1.0 mg/kg psilocybin. Following the conclusion of extinction training, mice were tested for cue-induced reinstatement. In experiments in rats, 24 female and 23 male rats underwent 15d of cocaine self-administration (0.8 mg/kg/infusion) and extinction training. Immediately following extinction trials, rats were injected with vehicle, 1.0 mg/kg psilocybin, or 2.5 mg/kg psilocybin. Following the conclusion of extinction training, rats were tested for cue-induced reinstatement. Psilocybin administered following extinction trials had no effect, as both female and male mice and rats demonstrated significant cue-induced reinstatement. These data suggest that psilocybin is ineffective at altering cocaine-seeking behavior in the paradigm and doses used in the current study. It remains to be seen whether treatment with psilocybin under different conditions may be useful in the long-standing goal of finding pharmacotherapies to treat CUD.
- Klíčová slova
- Addiction, Cocaine self-administration, Mice, Psilocybin, Rats, Reinstatement,
- MeSH
- autoaplikace * MeSH
- chování při shánění drogy * účinky léků MeSH
- extinkce (psychologie) * účinky léků MeSH
- halucinogeny * farmakologie aplikace a dávkování MeSH
- inhibitory vychytávání dopaminu farmakologie aplikace a dávkování MeSH
- kokain * farmakologie aplikace a dávkování MeSH
- krysa rodu Rattus MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- operantní podmiňování účinky léků MeSH
- podněty * MeSH
- pohlavní dimorfismus MeSH
- poruchy spojené s užíváním kokainu farmakoterapie psychologie MeSH
- potkani Sprague-Dawley MeSH
- psilocybin * farmakologie aplikace a dávkování MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- halucinogeny * MeSH
- inhibitory vychytávání dopaminu MeSH
- kokain * MeSH
- psilocybin * MeSH
Heavy maternal alcohol drinking during pregnancy has been associated with altered neurodevelopment in the child but the effects of low-dose alcohol drinking are less clear and any potential safe level of alcohol use during pregnancy is not known. We evaluated the effects of prenatal alcohol on reward-related behavior and substance use in young adulthood and the potential sex differences therein. Participants were members of the European Longitudinal Study of Pregnancy and Childhood (ELSPAC) prenatal birth cohort who participated in its neuroimaging follow-up in young adulthood. A total of 191 participants (28-30 years; 51% men) had complete data on prenatal exposure to alcohol, current substance use, and fMRI data from young adulthood. Maternal alcohol drinking was assessed during mid-pregnancy and pre-conception. Brain response to reward anticipation and reward feedback was measured using the Monetary Incentive Delay task and substance use in young adulthood was assessed using a self-report questionnaire. We showed that even a moderate exposure to alcohol in mid-pregnancy but not pre-conception was associated with robust effects on brain response to reward feedback (six frontal, one parietal, one temporal, and one occipital cluster) and with greater cannabis use in both men and women 30 years later. Moreover, mid-pregnancy but not pre-conception exposure to alcohol was associated with greater cannabis use in young adulthood and these effects were independent of maternal education and maternal depression during pregnancy. Further, the extent of cannabis use in the late 20 s was predicted by the brain response to reward feedback in three out of the nine prenatal alcohol-related clusters and these effects were independent of current alcohol use. Sex differences in the brain response to reward outcome emerged only during the no loss vs. loss contrast. Young adult men exposed to alcohol prenatally had significantly larger brain response to no loss vs. loss in the putamen and occipital region than women exposed to prenatal alcohol. Therefore, we conclude that even moderate exposure to alcohol prenatally has long-lasting effects on brain function during reward processing and risk of cannabis use in young adulthood.
- MeSH
- dospělí MeSH
- lidé MeSH
- longitudinální studie MeSH
- magnetická rezonanční tomografie * MeSH
- mozek * diagnostické zobrazování účinky léků patofyziologie MeSH
- odměna * MeSH
- pití alkoholu * psychologie škodlivé účinky MeSH
- sexuální faktory MeSH
- těhotenství MeSH
- zpožděný efekt prenatální expozice * patofyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Cooperation is common in animals, yet the specific mechanisms driving collaborative behaviour in different species remain unclear. We investigated the proximate mechanisms underlying the cooperative behaviour of bumblebees in two different tasks, where bees had to simultaneously push a block in an arena or a door at the end of a tunnel for access to reward. In both tasks, when their partner's entry into the arena/tunnel was delayed, bees took longer to first push the block/door compared with control bees that learned to push alone. In the tunnel task, just before gaining access to reward, bees were more likely to face towards their partner than expected by chance or compared with controls. These results show that bumblebees' cooperative behaviour is not simply a by-product of individual efforts but is socially influenced. We discuss how bees' turning behaviours, e.g. turning around before first reaching the door when their partner was delayed and turning back towards the door in response to seeing their partner heading towards the door, suggest the potential for active coordination. However, because these behaviours could also be interpreted as combined responses to social and secondary reinforcement cues, future studies are needed to help clarify whether bumblebees truly use active coordination.
- Klíčová slova
- bumblebees, collaboration, comparative cognition, insects, social behaviour,
- MeSH
- chování zvířat MeSH
- kooperační chování * MeSH
- odměna MeSH
- sociální chování MeSH
- včely fyziologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Acquiring knowledge about the environment is crucial for survival. Animals, often driven by their exploratory tendencies, gather valuable information regarding food resources, shelter, mating partners, etc. However, neophobia, or avoiding novel environmental stimuli, can constrain their exploratory behaviour. While neophobia can reduce potential predation risks, decreased exploratory behaviour resulting from it may limit the ability to discover highly rewarding resources. Dogs (Canis familiaris) living in semi-urban and urban environments as free-ranging populations, although subject to various selection forces, typically have negligible predation pressure. These dogs are scavengers in human-dominated environments; thus, selection against object-neophobia can provide benefits when searching for novel food resources. Although captive pack-living dogs are known to be less neophobic than their closest living ancestors, wolves (Canis lupus), little is known about free-ranging dogs' behavioural responses to novel objects, particularly in foraging contexts. Using an object choice experiment, we tested 259 free-ranging dogs from two age classes, adult and juvenile, to investigate their object-neophobia in a scavenging context. We employed a between-subject study design, providing dogs with a familiar and a potentially novel object, both baited with equal, hidden food items. Adult and juvenile dogs significantly inspected the novel object first compared to the familiar one, even when the hidden food item was partially visible. To validate these findings, we compared novel objects with different strengths of olfactory cues (baited vs. false-baited) and found that they were inspected comparably by adults and juveniles. No significant differences were found in the latencies to inspect the objects, suggesting that free-ranging dogs may still be cautious when exploring their environments. These results indicate that free-ranging dogs, evidently from an early ontogenetic phase, do not show object-neophobia, as demonstrated by their preference for novel over familiar food sources. We conclude that little to no constraint of neophobia on exploratory behaviour in semi-urban and urban-dwelling animals can guide foraging decision-making processes, providing adaptive benefits.
- Klíčová slova
- Canis familiaris, Exploration, Neophobia-neophilia, Novel objects, Urban adaptation,
- MeSH
- hospodářská zvířata * MeSH
- lidé MeSH
- odměna MeSH
- pátrací chování MeSH
- podněty MeSH
- psi MeSH
- ryby MeSH
- vlci * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- psi MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Fossils encompassing multiple individuals provide rare direct evidence of behavioral interactions among extinct organisms. However, the fossilization process can alter the spatial relationship between individuals and hinder behavioral reconstruction. Here, we report a Baltic amber inclusion preserving a female-male pair of the extinct termite species Electrotermes affinis. The head-to-abdomen contact in the fossilized pair resembles the tandem courtship behavior of extant termites, although their parallel body alignment differs from the linear alignment typical of tandem runs. To solve this inconsistency, we simulated the first stage of amber formation, the immobilization of captured organisms, by exposing living termite tandems to sticky surfaces. We found that the posture of the fossilized pair matches trapped tandems and differs from untrapped tandems. Thus, the fossilized pair likely is a tandem running pair, representing the direct evidence of the mating behavior of extinct termites. Furthermore, by comparing the postures of partners on a sticky surface and in the amber inclusion, we estimated that the male likely performed the leader role in the fossilized tandem. Our results demonstrate that past behavioral interactions can be reconstructed despite the spatial distortion of body poses during fossilization. Our taphonomic approach demonstrates how certain behaviors can be inferred from fossil occurrences.
- Klíčová slova
- actualistic paleontology, collective behavior, fossil record, leadership, movement coordination,
- MeSH
- extinkce (psychologie) MeSH
- Isoptera * MeSH
- jantar MeSH
- lidé MeSH
- postura těla MeSH
- zkameněliny MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- jantar MeSH
Self-control underlies goal-directed behaviour in humans and other animals. Delayed gratification - a measure of self-control - requires the ability to tolerate delays and/or invest more effort to obtain a reward of higher value over one of lower value, such as food or mates. Social context, in particular, the presence of competitors, may influence delayed gratification. We adapted the 'rotating-tray' paradigm, where subjects need to forgo an immediate, lower-quality (i.e. less preferred) reward for a delayed, higher-quality (i.e. more preferred) one, to test social influences on delayed gratification in two corvid species: New Caledonian crows and Eurasian jays. We compared choices for immediate vs. delayed rewards while alone, in the presence of a competitive conspecific and in the presence of a non-competitive conspecific. We predicted that, given the increased risk of losing a reward with a competitor present, both species would similarly, flexibly alter their choices in the presence of a conspecific compared to when alone. We found that species differed: jays were more likely to select the immediate, less preferred reward than the crows. We also found that jays were more likely to select the immediate, less preferred reward when a competitor or non-competitor was present than when alone, or when a competitor was present compared to a non-competitor, while the crows selected the delayed, highly preferred reward irrespective of social presence. We discuss our findings in relation to species differences in socio-ecological factors related to adult sociality and food-caching (storing). New Caledonian crows are more socially tolerant and moderate cachers, while Eurasian jays are highly territorial and intense cachers that may have evolved under the social context of cache pilfering and cache protection strategies. Therefore, flexibility (or inflexibility) in delay of gratification under different social contexts may relate to the species' social tolerance and related risk of competition.
The nucleus accumbens (NAc) is considered an interface between motivation and action, with NAc neurons playing an important role in promoting reward approach. However, the encoding by NAc neurons that contributes to this role remains unknown. We recorded 62 NAc neurons in male Wistar rats (n = 5) running towards rewarded locations in an 8-arm radial maze. Variables related to locomotor approach kinematics were the best predictors of the firing rate for most NAc neurons. Nearly 18% of the recorded neurons were inhibited during the entire approach run (locomotion-off cells), suggesting that reduction in firing of these neurons promotes initiation of locomotor approach. 27% of the neurons presented a peak of activity during acceleration followed by a valley during deceleration (acceleration-on cells). Together, these neurons accounted for most of the speed and acceleration encoding identified in our analysis. In contrast, a further 16% of neurons presented a valley during acceleration followed by a peak just prior to or after reaching reward (deceleration-on cells). These findings suggest that these three classes of NAc neurons influence the time course of speed changes during locomotor approach to reward.
- Klíčová slova
- Nucleus accumbens, initiation of action, kinematics encoding, locomotor speed, reward approach,
- MeSH
- biomechanika MeSH
- krysa rodu Rattus MeSH
- lokomoce MeSH
- neurony * fyziologie MeSH
- nucleus accumbens * fyziologie MeSH
- odměna MeSH
- potkani Wistar MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Methylphenidate is a stimulant used to treat attention deficit and hyperactivity disorder (ADHD). In the last decade, illicit use of methylphenidate has increased among healthy young adults, who consume the drug under the assumption that it will improve cognitive performance. However, the studies that aimed to assess the methylphenidate effects on memory are not consistent. Here, we tested whether the effect of methylphenidate on a spatial memory task can be explained as a motivational and/or a reward effect. We tested the effects of acute and chronic i.p. administration of 0.3, 1 or 3 mg/kg of methylphenidate on motivation, learning and memory by using the 8-arm radial maze task. Adult male Wistar rats learned that 3 of the 8 arms of the maze were consistently baited with 1, 3, or 6 sucrose pellets, and the number of entries and reentries into reinforced and non-reinforced arms of the maze were scored. Neither acute nor chronic (20 days) methylphenidate treatment affected the number of entries in the non-baited arms. However, chronic, but not acute, 1-3 mg/kg methylphenidate increased the number of reentries in the higher reward arms, which suggests a motivational/rewarding effect rather than a working memory deficit. In agreement with this hypothesis, the methylphenidate treatment also decreased the approach latency to the higher reward arms, increased the approach latency to the low reward arm, and increased the time spent in the high, but not low, reward arm. These findings suggest that methylphenidate may act more as a motivational enhancer rather than a cognitive enhancer in healthy people.
- Klíčová slova
- Attention deficit hyperactivity disorder, Dopamine, Incentive salience, Methylphenidate, Motivation, Spatial memory,
- MeSH
- hyperkinetická porucha * farmakoterapie MeSH
- krysa rodu Rattus MeSH
- methylfenidát * farmakologie terapeutické užití MeSH
- motivace MeSH
- odměna MeSH
- potkani Wistar MeSH
- stimulanty centrálního nervového systému * farmakologie terapeutické užití MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- methylfenidát * MeSH
- stimulanty centrálního nervového systému * MeSH
