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The integration of gambling-like features in modern gaming blurs the line between gaming and gambling. Rapidly evolving monetisation strategies in games, especially microtransactions like loot boxes, exploit psychological reward processes similar to gambling disorder. These include variable ratio schedules, positively reinforced wins, and near-miss effects, among others. Such mechanisms encourage impulsive spending, prolonged engagement, and the development of problematic habits. The risks involved are especially concerning for younger players and individuals with comorbid mental health disorders, who may be more vulnerable to these features. Despite these clear parallels with gambling, regulatory frameworks often fail to address the overlap, leaving consumers exposed to financial and psychological harm. This editorial highlights the urgent need for an updated gambling definition in the context of gaming, increased transparency in game design, stricter age restrictions, and stronger regulatory oversight to safeguard player well-being as the industry continues to expand.
We consider interacting urns on a finite directed network, where both sampling and reinforcement processes depend on the nodes of the network. This extends previous research by incorporating node-dependent sampling and reinforcement. We classify the sampling and reinforcement schemes, as well as the networks on which the proportion of balls of either colour in each urn converges almost surely to a deterministic limit. We also investigate conditions for achieving synchronisation of the colour proportions across the urns and analyse fluctuations under specific conditions on the reinforcement scheme and network structure.
Chapter 6 deals with national newspaper effects, especially the claimed influence of the Sun over the voting behaviour of its readers. The associations between newspaper reading and political attitudes and behaviour over the past decades is traced, together with the popular claim that the media, notably national newspapers, set the election agenda for the population. A large body of research finds little or no evidence of strong newspaper effects on party voting and national election agendas. Instead we find strong effects of the normal demographic variables that are usually associated with many forms of social and political behaviour – the standard model of the behavioural sciences.
This chapter offers an example of the role of the Bank in European state finance. The kingdom of Prussia made heavy use of the Bank during the Seven Years War (1756—1763). Public finance in Prussia during this period was primitive, lacking basic features such as a bond market or central bank. Under heavy financial pressure, Prussian King Frederick II chose to finance much of the war through the production of debased coinage. The task of minting debased coins was outsourced to private contractors (“mint entrepreneurs”), who purchased much of the necessary silver in Amsterdam, making use of credit which was abundant in the Amsterdam market. Details of these transactions are revealed in the Bank’s ledgers. Frederick also relied on gold subsidies from Great Britain, which were paid via Amsterdam and can also be matched to Bank records. Finally, at the end of the war, Frederick called upon his entrepreneurs to engineer a reverse debasement (reinforcement). This activity once again relied heavily on Dutch resources, including remote smelting furnaces, Amsterdam credit, and Bank money. Traces of the entrepreneurs’ activity can again be seen in the Bank’s records.
Operant procedures occupy a prominent role within animal welfare science because they provide information about the strength of animals’ preferences. It is assumed that strongly motivated choices commonly indicate conditions necessary for uncompromised welfare. A review of the literature shows that members of many species will work for access to resources not commonly provided to them; including a secure resting place (perches for hens or boxes for rodents) and substrates for species-typical activities such as nesting, digging and rooting (in hens, rats, mice and pigs). Despite a recent surge in popularity, operant techniques remain under-utilised and studies employing them struggle to find the best method for prioritising resources. In order to fully exploit the potential of operant procedures a wider appreciation of the relevant theories and techniques might be beneficial; including greater employment of the basic principles of reinforcement theory and further development of more complex economic analogies. If these two strands of research develop together, operant approaches have a key role to play in refining and replacing husbandry practices that undermine animal welfare.
Twenty horses were paired for age, sex and breed and placed into one of two groups. The horses in Group A (control) were reinforced using only negative reinforcement (NR) while those in group B (treatment) were reinforced with both positive reinforcement (PR) and NR concurrently. All horses were shaped for the halt response while being driven in long-reins over a period of 5 consecutive days. On day I, all horses were given a baseline test of 20 random halts while being long-reined in an indoor arena. On days 2-4, the shaping of the halt response continued with horses being reinforced according to the group to which they had been allocated. On day 5 of testing the baseline test was repeated (final test). During the baseline and final tests, behavioural responses and accuracy of completion of the halt response were recorded. Heart rates were recorded continuously during testing. One-way analysis of variance in randomised blocks and analysis of covariance using baseline data as a covariate showed no effect on latency to halt. However, horses reinforced with both NR and PR shook their heads vertically less and were more likely to lick their lips than those reinforced with NR only. There was also a trend for an increase in roundness of outline of the horses that were reinforced with both PR and NR. These results suggest that the implementation of PR effectively into equitation training may improve the welfare of the horse.
The May 2019 IPBES emphasised the scale of the current biodiversity crisis and the need for transformative change, but highlighted that the tools exist to enable this change. Conservation translocation is an increasingly used tool that involves people deliberately moving and releasing organisms where the primary goal is conservation – it includes species reintroductions, reinforcements, assisted colonisations and ecological replacements. It can be complex, expensive, time consuming, and sometimes controversial, but when best practice guidelines are followed it can be a very effective conservation method and a way of exciting and engaging people in environmental issues. Conservation translocations have an important role to play not only in improving the conservation status of individual species but also in ecological restoration and rewilding by moving keystone and other influential species. As the climate continues to change, species with poor dispersal abilities or opportunities will be at particular risk. Assisted colonisation, which involves moving species outside their indigenous range, is likely to become an increasingly used method. It is also a tool that may become increasingly used to avoid threats from the transmission of pathogens. Other more radical forms of conservation translocation, such as ecological replacements, multi-species conservation translocations, and the use of de-extinction and genetic interventions, are also likely to be given stronger consideration within the wider framework of ecological restoration. There have been significant advances in the science of reintroduction biology over the last three decades. However new ways of transferring and sharing such information are needed to enable a wider spectrum of practitioners to have easier access to knowledge and guidance. In the past the biological considerations of conservation translocations have often heavily outweighed the people considerations. However it is increasingly important that socio-economic factors are also built into projects and relevant experts involved to reduce conflict and improve the chances of success. Some level of biological and socio-economic risk will be present for most conservation translocations, but these can often be managed through the use of sensitivity, professionalism, and the application of tried and tested best practice. The role of species reintroduction and other forms of conservation translocations will be an increasingly important tool if we are to restore, and make more resilient, our damaged ecosystems.
In total, 600 two-year-old and three-year-old saplings of the critically endangered Chinese endemic huagaimu were translocated into the species’ natural range. There were very low survival rates (2 and 20 per cent respectively) of translocated individuals at two sites in Xichou county, with a much higher survival rate of 74 per cent at two sites in Maguan county. The over-riding determinant of translocation success is considered to be the difference in horticultural practices used in the different translocations, with much more favourable outcomes associated with greater horticultural training and expertise.
Although conservation translocations always aim to result in ‘conservation benefit’ for a species or ecosystem, there are many motivations and contexts in which people undertake conservation translocations. Establishing a need for translocations involves considering other ways to deliver the ‘conservation benefit’ to a species or ecosystem. Typically, translocations are initiated alongside other conservation measures. Destination sites must be carefully selected based on more than just vegetation type; attention must be paid to climate, biotic interactions, and other species’ requirements for survival. Socio-economic risks and benefits and legislative constraints should also be considered when evaluating destination sites. Translocated plants, animals, or fungi may be sourced from in situ or ex situ populations, or a combination of the two. Ideally, source populations are those that can support the removal of individuals for translocation without negative consequences for individuals that remain in the wild. It also helps to have ecological similarity between source and destination sites when using wild individuals. Releases should only occur where the original cause of extirpation/decline has been minimised. The choice of one or several sites, and the possibility of several releases over multiple timepoints should be considered, perhaps using pilot releases to evaluate suitability. Monitoring is crucial to being able to report the outcome of the conservation translocation but, perhaps more importantly, allows the translocation team to adapt to changes in status and may prompt the implementation of an exit strategy. Sharing monitoring results is important for others to benefit from lessons learnt. Seek as much advice as you can in the planning phases and build a team that can deliver the various components of the project.
We are using communication and engagement with stakeholders to attempt to foster positive view of eagles. We are exploring the opportunities for nature-based tourism to highlight the benefits of eagles. We are taking a partnership approach with equal input from land management sectors and conservationists.
Conservation translocation - the movement of species for conservation benefit - includes reintroducing species into the wild, reinforcing dwindling populations, helping species shift ranges in the face of environmental change, and moving species to enhance ecosystem function. Conservation translocation can lead to clear conservation benefits and can excite and engage a broad spectrum of people. However, these projects are often complex and involve careful consideration and planning of biological and socio-economic issues. This volume draws on the latest research and experience of specialists from around the world to help provide guidance on best practice and to promote thinking over how conservation translocations can continue to be developed. The key concepts cover project planning, biological and social factors influencing the efficacy of translocations, and how to deal with complex decision-making. This book aims to inspire, inform and help practitioners maximise their chances of success, and minimise the risks of failure.
We introduce a general two-colour interacting urn model on a finite directed graph, where each urn at a node reinforces all the urns in its out-neighbours according to a fixed, non-negative, and balanced reinforcement matrix. We show that the fraction of balls of either colour converges almost surely to a deterministic limit if either the reinforcement is not of Pólya type or the graph is such that every vertex with non-zero in-degree can be reached from some vertex with zero in-degree. We also obtain joint central limit theorems with appropriate scalings. Furthermore, in the remaining case when there are no vertices with zero in-degree and the reinforcement is of Pólya type, we restrict our analysis to a regular graph and show that the fraction of balls of either colour converges almost surely to a finite random limit, which is the same across all the urns.
Agitation and aggression are common behavioral manifestations in patients with PWS. This chapter reviews how to recognize possible triggers and psychological mechanisms behind them. Caregivers are made aware of operant conditioning and the stages of moral development. Additionally the role of externalization is described. The underlying cause of the agitation can vary from person to person and similarly the management strategy differs considerably. The importance of ensuring the safety of the patient and others is emphasized. Behavioral management techniques can be very effective when started at an early age. Medications are effective options to supplement behavioral strategies as long as they are prescribed under the close monitoring of a medical provider. Finally, remember that most patients with PWS do not have malicious intent when they are exhibiting aggression. Their aggression is rooted in poor impulse control and hence is reactive in nature. Their aggression should be treated as a symptom rather than an inherent character flaw.
A wide variety of events can function as reinforcers. The Premack principle provides a useful guide; activities that individuals engage in when given a free choice will probably be effective reinforcers. One factor is the delay between the response and reinforcer; we discount, or give less value, to rewards that are delayed. Effectiveness also depends on the schedule of reinforcement; partial reinforcement (reinforcing only some responses) produces greater persistence in extinction. Effectiveness also depends on how the reinforcer contrasts with past reinforcers—we value a reinforcer less if we are accustomed to more attractive reinforcers—and how long we have been deprived of it. The stimuli present during reinforcement are also important; we are more likely to repeat a response if we are in the same environment where we obtained it previously. Which elements of that environment will be important, though, can be difficult to predict, depending in part on attention and perceptual learning (with practice we can become better at distinguishing elements of a situation). The chapter ends with an application involving shaping—when a behavior is difficult to train, start by reinforcing the response closest to it, and then gradually reinforce closer approximations.
The first text to integrate behavioral and cognitive approaches to learning and memory, this engaging textbook emphasizes human research, reflecting the field's evolution. Learning and Memory also recognizes the vital contribution of animal research, covering all historically important studies. Written in a lively and conversational style, this second edition encourages students to think critically. One example is its exploration of the Rescorla-Wagner model, the most important theory of conditioning, now further streamlined to improve student comprehension. Another is the addition of critical-thinking questions, which encourage students to evaluate their reactions to the material they've read, and relate findings to their own lives. Research includes an emphasis on practical applications such as treatments for phobias, addictions, and autism; the arguments for and against corporal punishment; whether recovered memories and eyewitness testimony should be believed; and effective techniques for studying. The text concludes with an overview of neural networks and deep learning.
We consider a model of N interacting two-colour Friedman urns. The interaction model considered is such that the reinforcement of each urn depends on the fraction of balls of a particular colour in that urn as well as the overall fraction of balls of that colour in all the urns combined together. We show that the urns synchronize almost surely and that the fraction of balls of each colour converges to the deterministic limit of one-half, which matches with the limit known for a single Friedman urn. Furthermore, we use the notion of stable convergence to obtain limit theorems for fluctuations around the synchronization limit.
Magnolia sinica, a Critically Endangered tree endemic to Yunnan, China, is one of the 20 plant species with extremely small populations approved by the Yunnan government for urgent rescue action before 2015. Information on the geographical distribution and population size of this species had not previously been reported, hindering effective conservation. We therefore carried out a survey of the literature and of herbarium specimens, followed by a detailed field survey and morphological measurements and observations of surviving individuals. We located 52 individuals in the wild, in eight localities. Two distinguishing morphological characters (tepal colour and tepal number) were revised based on observations of all remaining wild individuals that produced flowers and on one 30-year-old flowering plant in Kunming Botanical Garden. The survival rate of individuals propagated from seed for ex situ conservation at the Garden was 100% over 5 years; of 100 individuals transplanted to each of two reinforcement sites, 20 and 18, respectively, were alive after 6 years. We propose two groups of measures to protect M. sinica: (1) in situ conservation, population monitoring, and public engagement, and (2) ex situ conservation with reinforcement or reintroduction.
Altered corticostriatothalamic encoding of reinforcement is a core feature of depression. Here we examine reinforcement learning in late-life depression in the theoretical framework of the vascular depression hypothesis. This hypothesis attributes the co-occurrence of late-life depression and poor executive control to prefrontal/cingulate disconnection by vascular lesions.
Method
Our fMRI study compared 31 patients aged ⩾60 years with major depression to 16 controls. Using a computational model, we estimated neural and behavioral responses to reinforcement in an uncertain, changing environment (probabilistic reversal learning).
Results
Poor executive control and depression each explained distinct variance in corticostriatothalamic response to unexpected rewards. Depression, but not poor executive control, predicted disrupted functional connectivity between the striatum and prefrontal cortex. White-matter hyperintensities predicted diminished corticostriatothalamic responses to reinforcement, but did not mediate effects of depression or executive control. In two independent samples, poor executive control predicted a failure to persist with rewarded actions, an effect distinct from depressive oversensitivity to punishment. The findings were unchanged in a subsample of participants with vascular disease. Results were robust to effects of confounders including psychiatric comorbidities, physical illness, depressive severity, and psychotropic exposure.
Conclusions
Contrary to the predictions of the vascular depression hypothesis, altered encoding of rewards in late-life depression is dissociable from impaired contingency learning associated with poor executive control. Functional connectivity and behavioral analyses point to a disruption of ascending mesostriatocortical reward signals in late-life depression and a failure of cortical contingency encoding in elderly with poor executive control.
In 1957, Skinner, in his “Verbal Behavior”, proposed an explanation on how a language is learned. In 1959, Chomsky strongly argued the non-learnability of language, establishing in the field of developmental psycholinguistics the substitution of the term “learning” for that of “acquisition”. Currently, the constructivist models describe language acquisition as a process of ontogenetic, gradual, complex, and adaptive change. This new theoretical framework has been especially useful for rereading Verbal Behavior because it facilitates recovering the Skinnerian learning mechanisms. This can be observed in the recent research trends that recapture reinforcement and imitation (echoic responses), although they are now located in the initial phases of the process and are included in a cognitive dynamic that, by gradually increasing its complexity, can achieve grammar. The new constructivist theoretical framework, by retrieving the functional and referential aspects of language, can also take advantage of the classic Skinnerian proposal about the pragmatic types of verbal behavior, providing it with new meaning.
Psychostimulants, including amphetamine (AMPH), exert robust arousal-enhancing, reinforcing and locomotor-activating effects. These behavioural actions involve drug-induced elevations in extracellular norepinephrine (NE) and dopamine (DA) within a variety of cortical and subcortical regions. The lateral hypothalamic area (LHA), including the lateral hypothalamus proper, perifornical area and adjacent dorsomedial hypothalamus, is implicated in appetitive- and arousal-related processes. The LHA is innervated by both NE and DA projections and systemically administered AMPH has been demonstrated to activate LHA neurons. Combined, these and other observations suggest the LHA may be a site of action in the behavioural effects of psychostimulants. To test this hypothesis, we examined the degree to which AMPH (10 nmol, 25 nmol) acts within the LHA to exert arousing, locomotor-activating and reinforcing actions in quietly resting/sleeping rats. Although intra-LHA AMPH robustly increased time spent awake, this occurred in the absence of pronounced locomotor activation or reinforcing actions, as measured in a conditioned place preference (CPP) paradigm. Arousing and stressful conditions or drug re-exposure can elicit relapse in humans and reinstate drug-seeking in animals. Given the LHA is also implicated in the reinstatement of drug-seeking behaviour, additional studies examined whether AMPH acts within the LHA to reinstate an extinguished CPP produced with systemic AMPH administration. Our results demonstrate that AMPH action within the LHA is sufficient to reinstate drug-seeking behaviour, as measured in this paradigm. Collectively, these observations demonstrate that psychostimulants act within the LHA to elicit affectively neutral arousal and reinstate drug-seeking behaviour.