This article reviews the behavioral neuroscience of extinction, the phenomenon in which a behavior that has been acquired through Pavlovian or instrumental (operant) learning decreases in strength ...when the outcome that reinforced it is removed. Behavioral research indicates that neither Pavlovian nor operant extinction depends substantially on erasure of the original learning but instead depends on new inhibitory learning that is primarily expressed in the context in which it is learned, as exemplified by the renewal effect. Although the nature of the inhibition may differ in Pavlovian and operant extinction, in either case the decline in responding may depend on both generalization decrement and the correction of prediction error. At the neural level, Pavlovian extinction requires a tripartite neural circuit involving the amygdala, prefrontal cortex, and hippocampus. Synaptic plasticity in the amygdala is essential for extinction learning, and prefrontal cortical inhibition of amygdala neurons encoding fear memories is involved in extinction retrieval. Hippocampal-prefrontal circuits mediate fear relapse phenomena, including renewal. Instrumental extinction involves distinct ensembles in corticostriatal, striatopallidal, and striatohypothalamic circuits as well as their thalamic returns for inhibitory (extinction) and excitatory (renewal and other relapse phenomena) control over operant responding. The field has made significant progress in recent decades, although a fully integrated biobehavioral understanding still awaits.
Pavlovian conditioning is typically distinguished from sensitization but a Pavlovian conditional stimulus (CS) also results in sensitization. A Pavlovian CS can sensitize responding to a probe ...stimulus that is related to the unconditional stimulus (US) or to the US itself. Pavlovian sensitization has been studied in the defensive, sexual, and feeding systems. In Pavlovian sensitization, the focus is not on a conditional response (CR) directly elicited by the CS but on the response mode that is activated by the CS. Activation of a response mode increases the probability of particular responses and also increases reactivity to various stimuli. Pavlovian sensitization reflects this increased stimulus reactivity. Pavlovian sensitization helps uncover successful learning in situations where a conventional CR does not occur. Pavlovian sensitization also encourages broadening our conceptions of Pavlovian conditioning to include changes in afferent processes. Implications for biological fitness and for basic and translational research are discussed.
•Pavlovian sensitization is especially important when learning is not evident in a conditional response.•Pavlovian sensitization is of biological significance because it improves reactivity to unconditional stimuli.•Pavlovian sensitization encourages reconsidering common assumptions about the nature of sensitization.•Pavlovian sensitization highlights the importance of afferent processes in the neurobiology of learning and extinction.
The building industry nowadays is facing two major challenges – the increased concern for energy reduction and the growing need for comfort improvements. These challenges have led many researchers to ...develop a personalized conditioning system. Personalized conditioning aims to create a microclimate zone around a single workplace. In this way the energy is deployed only where it is actually needed, and the individual needs for thermal comfort are fulfilled. In recent years personalized conditioning has received a lot of attention in research publications. This paper reviews the impact of different personalized conditioning systems on thermal comfort and building energy performance. In the reviewed publications, it was demonstrated that thermal comfort can be well maintained at ambient temperatures that are 4–5K higher as well as lower than the temperatures recommended by current standards. Personalized conditioning also allows reduction in energy consumption due to an increased cooling setpoint, a decreased heating setpoint, or a decreased ventilation rate of the background system. Energy simulations show that reductions of up to 60% can be achieved.
Contexts and discrete stimuli often hierarchically influence the association between a stimulus and outcome. This phenomenon, called occasion setting, is central to modulation-based Pavlovian ...learning. We conducted two experiments with humans in fear and appetitive conditioning paradigms, training stimuli in differential conditioning, feature-positive discriminations, and feature-negative discriminations. We also investigated the effects of trait anxiety and trait depression on these forms of learning. Results from both experiments showed that participants were able to successfully learn which stimuli predicted the electric shock and monetary reward outcomes. Additionally, as hypothesized, the stimuli trained as occasion setters had little-to-no effect on simple reinforced or non-reinforced stimuli, suggesting the former were indeed occasion setters. Lastly, in fear conditioning, trait anxiety was associated with increases in fear of occasion setter/conditional stimulus compounds; in appetitive conditioning, trait depression was associated with lower expectations of monetary reward for the trained negative occasion setting compound and transfer of the negative occasion setter to the simple reinforced stimulus. These results suggest that clinically anxious individuals may have enhanced fear of occasion setting compounds, and clinically depressed individuals may expect less reward with compounds involving the negative occasion setter.
•Two experiments on Pavlovian occasion setting in human fear and reward conditioning.•Participants learned simple associations and positive & negative occasion setting.•Transfer tests suggest that occasion setting was indeed learned where expected.•Trait anxiety predicted greater fear in positive & negative occasion setting.•Trait depression predicted lower monetary expectancy in negative occasion setting.
Thoroughly revised, this book provides the reader with an understanding of the principles and practices of testing and balancing (TAB) heating, ventilating, and air conditioning (HVAC) air and water ...systems. For the novice and the experienced testing and balancing technician, it is a field reference book of procedures, equations, and information tables.
Divided into five parts, Part I has general and specific balancing procedures for constant air volume systems, variable air volume systems, return air systems, and fans and fan performance. Part II covers testing and balancing fume hood systems and cleanrooms, commissioning HVAC systems, centrifugal pumps and pump performance, analog and digital controls and water balancing procedures using flow meters, system components, and temperatures. Part III covers fans, pumps, air distribution, water distribution, motors, electrical, fluid flow, psychrometrics, refrigeration, and instrument usage and care. Part IV includes equations and tables. New to this edition, Part V has information and additional test and balance procedures and graphics for chapters 1-7 and 13-14. TAB Data and Test forms are in the new addendum as well.
Provides the readers with revised information about the principles and practices of testing and balancing (TAB) heating
Represents a field reference guide for both the novice and experienced testing and balancing technician
Includes a new section with information and additional test and balance procedures and graphics
Appetitive Pavlovian-instrumental Transfer: A review Cartoni, Emilio; Balleine, Bernard; Baldassarre, Gianluca
Neuroscience and biobehavioral reviews,
December 2016, 2016-Dec, 2016-12-00, 20161201, Letnik:
71
Journal Article
Recenzirano
Odprti dostop
•We present a systematic review of appetitive Pavlovian Instrumental Transfer.•We review and discuss all major experiments and interpretations.•We discuss the interactions between transfer and drugs ...of abuse.•We examine the recent applications of transfer to human participants.•We highlight open problems, such as inhibition and the function of transfer.
Reward-related cues are an important part of our daily life as they often influence and guide our actions. This paper reviews one of the experimental paradigms used to study the effects of cues, the Pavlovian to Instrumental Transfer paradigm. In this paradigm, cues associated with rewards through Pavlovian conditioning alter motivation and choice of instrumental actions. The first transfer experiments date back to the 1940s, but only in the last decade has it been fully recognised that there are two types of transfer, specific and general. This paper presents a systematic review of both the neural substrates and the behavioral factors affecting both types of transfer. It also examines the recent application of the paradigm to study the effect of cues on human participants, both in normal and pathological conditions, and the interactions of transfer with drugs of abuse. Finally, the paper analyses the theoretical aspects of transfer to build an overall picture of the phenomenon, from early theories to recent hierarchical accounts.
Abstract
Unexpected cardiac adverse effects are the leading causes of discontinuation of clinical trials and withdrawal of drugs from the market. Since the original observations in the mid-90s, it ...has been well established that cardiovascular risk factors and comorbidities (such as ageing, hyperlipidaemia, and diabetes) and their medications (e.g. nitrate tolerance, adenosine triphosphate-dependent potassium inhibitor antidiabetic drugs, statins, etc.) may interfere with cardiac ischaemic tolerance and endogenous cardioprotective signalling pathways. Indeed drugs may exert unwanted effects on the diseased and treated heart that is hidden in the healthy myocardium. Hidden cardiotoxic effects may be due to (i) drug-induced enhancement of deleterious signalling due to ischaemia/reperfusion injury and/or the presence of risk factors and/or (ii) inhibition of cardioprotective survival signalling pathways, both of which may lead to ischaemia-related cell death and/or pro-arrhythmic effects. This led to a novel concept of ‘hidden cardiotoxicity’, defined as cardiotoxity of a drug that manifests only in the diseased heart with e.g. ischaemia/reperfusion injury and/or in the presence of its major comorbidities. Little is known on the mechanism of hidden cardiotoxocity, moreover, hidden cardiotoxicity cannot be revealed by the routinely used non-clinical cardiac safety testing methods on healthy animals or tissues. Therefore, here, we emphasize the need for development of novel cardiac safety testing platform involving combined experimental models of cardiac diseases (especially myocardial ischaemia/reperfusion and ischaemic conditioning) in the presence and absence of major cardiovascular comorbidities and/or cotreatments.
Air Conditioning System Design summarizes essential theory and then explains how the latest air conditioning technology operates. Load calculations, energy efficiency, and selection of technology are ...all explained in the context of air conditioning as a system, helping the reader fully consider the implications of design decisions. Whether users need to figure out how to apply their mechanical engineering degree to an air conditioning design task or simply want to find out more about air conditioning technology for a research project, this book provides a perfect guide. * Approaches air conditioning as a system, not just a collection of machines * Covers the essential theory on fluid flow and the latest in A/C technology in a very readable and easy-to-use style * Explains the significance of factors, such as climate and thermal comfort as A/C design considerations * Addresses design using a range of air conditioning technologies, such as evaporative cooling, VRF systems, psychromatic software, and dessicant dehumidification
Research on avoidance conditioning began in the late 1930s as a way to use laboratory experiments to better understand uncontrollable fear and anxiety. Avoidance was initially conceived of as a ...two-factor learning process in which fear is first acquired through Pavlovian aversive conditioning (so-called fear conditioning), and then behaviors that reduce the fear aroused by the Pavlovian conditioned stimulus are reinforced through instrumental conditioning. Over the years, criticisms of both the avoidance paradigm and the two-factor fear theory arose. By the mid-1980s, avoidance had fallen out of favor as an experimental model relevant to fear and anxiety. However, recent progress in understanding the neural basis of Pavlovian conditioning has stimulated a new wave of research on avoidance. This new work has fostered new insights into contributions of not only Pavlovian and instrumental learning but also habit learning, to avoidance, and has suggested that the reinforcing event underlying the instrumental phase should be conceived in terms of cellular and molecular events in specific circuits rather than in terms of vague notions of fear reduction. In our approach, defensive reactions (freezing), actions (avoidance) and habits (habitual avoidance) are viewed as being controlled by unique circuits that operate nonconsciously in the control of behavior, and that are distinct from the circuits that give rise to conscious feelings of fear and anxiety. These refinements, we suggest, overcome older criticisms, justifying the value of the new wave of research on avoidance, and offering a fresh perspective on the clinical implications of this work.
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