Converging data from different disciplines are showing the role of classical conditioning processes in the elaboration of human and animal behavior to be larger than previously supposed. Restricted views of classically conditioned responses as merely secretory, reflexive, or emotional are giving way to a broader conception that includes problem-solving, and other rule-governed behavior thought to be the exclusive province of either operant conditiońing or cognitive psychology. These new views have been accompanied by changes in the way conditioning (...) is conducted and evaluated. Data from a number of seemingly unrelated phenomena such as relapse to drug abuse by postaddicts, the placebo effect, and the immune response appear to involve classical conditioning processes. Classical conditioning, moreover, has been found to occur in simpler and simpler organisms and recently even demonstrated in brain slices and in utero. This target article will integrate the several research areas that have used the classical conditioning process as an explanatory model; it will challenge teleological interpretations of the classically conditioned CR and offer some basic principles for testing conditioning in diverse areas. (shrink)

Taste-aversion learning has been a popular paradigm for examining associative processes because it often produces outcomes that are different from those observed in other classical conditioning paradigms. One such outcome is taste-mediated odor potentiation in which aversion conditioning with a weak odor and a strong taste results in increased or synergistic conditioning to the odor. Because this strengthened odor aversion was not anticipated by formal models of learning, investigation of taste-mediated odor potentiation was a hot topic (...) in the 1980s. The present manuscript reviews the history of potentiation research with particular focus given to the stimuli that produce potentiation, the conditions that produce potentiation, the possible mechanism of this phenomenon, and possible reasons for the decline of research in this area. Although the number of published reports of potentiation has decreased since the 1980s, recent physiological and behavioral assessments have advanced the field considerably, and the opportunities for future research are bountiful. Recent physiological experiments, for example, have identified the basolateral nucleus of the amygdala as the key brain region to produce taste-mediated odor potentiation (e.g., Hatfield andGallagher, 1995). Also, recent behavioral experiments have extended the generality of synergistic conditioning effects. Studies have shown that odor can potentiate responding to taste (Slotnick, Westbrook and Darling, 1997) and that augmented responding can be produced in the A+/AX+blocking design (e.g., Batsell and Batson, 1999). With the current understanding of where synergistic conditioning may occur in the brain and the new tools to explore synergistic conditioning, we propose various directions for future research to determine whether taste-aversion learning and synergistic conditioning require unique explanations. (shrink)

Taste-aversion learning has been a popular paradigm for examining associative processes because it often produces outcomes that are different from those observed in other classical conditioning paradigms. One such outcome is taste-mediated odor potentiation in which aversion conditioning with a weak odor and a strong taste results in increased or synergistic conditioning to the odor. Because this strengthened odor aversion was not anticipated by formal models of learning, investigation of taste-mediated odor potentiation was a hot topic (...) in the 1980s. The present manuscript reviews the history of potentiation research with particular focus given to the stimuli that produce potentiation, the conditions that produce potentiation, the possible mechanism of this phenomenon, and possible reasons for the decline of research in this area. Although the number of published reports of potentiation has decreased since the 1980s, recent physiological and behavioral assessments have advanced the field considerably, and the opportunities for future research are bountiful. Recent physiological experiments, for example, have identified the basolateral nucleus of the amygdala as the key brain region to produce taste-mediated odor potentiation (e.g., Hatfield andGallagher, 1995). Also, recent behavioral experiments have extended the generality of synergistic conditioning effects. Studies have shown that odor can potentiate responding to taste (Slotnick, Westbrook and Darling, 1997) and that augmented responding can be produced in the A+/AX+blocking design (e.g., Batsell and Batson, 1999). With the current understanding of where synergistic conditioning may occur in the brain and the new tools to explore synergistic conditioning, we propose various directions for future research to determine whether taste-aversion learning and synergistic conditioning require unique explanations. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:32. HUME'S CLASSICAL THEORY OF JUSTICE1 Let me begin by formulating a broad distinction between two sorts of theories of justice. I shall stipulate that a modern theory of justice is one which treats justice as a moral quality, in fact as one moral quality among a multitude of moral virtues, and which accordingly takes the obligation tö' be just as pre-eminently a moral obligation. On this approach (...) the philosophical appreciation of justice requires that we interpret it in terms of a moral theory, and correspondingly any viable moral theory is expected to afford a framework within which the virtue of justice is to be understood. The important philosophical question to be asked about justice concerns the moral obligation to abide by the conventions and rules of justice. By a classical theory of justice I mean one which treats this quality not as one moral virtue among many others but as fundamental to morality itself. Here justice would have to be explained before one could develop a satisfactory account of morality. Questions about the moral obligation of justice are on this approach not as important philosophically as questions about the basis of justice itself. The modern and the classical theories are distinguished by the relationship each posits between justice and morality. In the modern approach, the account one offers of morality conditions the account one can offer of justice, while in the classical theory the account one offers of justice conditions the account one can offer of morality. As exemplifying a classical theory of justice one might cite Plato's Republic or, closer to the present topic, Hobbes' De Homi ne. While there seems to be no definitive interpretation of Hobbes ' overall moral and political theories, in this work he maintains that the development of a settled morality is subsequent to the establishment of civil society and therein, of course, also of the order of justice. The following passage from the De Homine shows how the order 33. of civil justice plays a foundational role relative to the moral order. Eut whatsoever is the object of any man's appetite or desire, that is it which he for his part calleth good: and the object of his hate and aversion, evil; and of his contempt, vile and inconsiderable. For these words of good, evil, and contemptible, are ever used with relation to the person that useth them: there being nothing simply and absolutely so; nor any common rule of good and evil, to be taken from the nature of the objects themselves; but from the person of the man, where there is no commonwealth; or, in a commonwealth, from the person that representeth it; or from an arbitrator or judge, whom men disagreeing shall by consent set up, and make his sentence the rule thereof. 2 Attributing to Hobbes the view that the account one gives of justice and the civil order conditions and serves as a necessary presupposition to the account one can give of a settled morality permits us to count Hobbes among those thinkers who have offered a classical theory of justice. Because Hume seems in so many ways to deserve the appellation of thoroughly modern philosopher, it is not surprising that he is naturally construed as sharing in the modern conception of justice. I want to argue that this way of interpreting Hume is mistaken and that he is in fact a classical theorist of justice. I shall contend, furthermore, that getting clear about the kind of theory of justice Hume offers allows us to resolve a problem in his moral theory—specifically a problem relating to the correction of the moral judgment. In view of these aims, the paper has three parts: (1) investigation as to what kind of theory of justice Hume offers; (2) exploration of a quandary inherent in the modernist interpretation which serves as an objection to the thesis of this paper; and (3) resolution of this objection and conclusion as to the character of Hume's theory of morality. At the end I shall explore a few corollaries 34. of the thesis that Hume is a classical theorist of justice. 1. Hume: A Classical Theorist of Justice There are... (shrink)

ABSTRACTIn Sinicized Asia, justice, conceptualized and institutionalized in its current form on a Western mold is part of a singular and ancient Confucian legal tradition.In this paper, it will be argued that Confucians initially articulated the concept of justice in relation to their own explanation of the world and their ideal, which distinguishes and rewards men’s actions according to their merits and social condition.It will be shown that Confucius’s thinking is primarily political and suggests ways of harmoniously organizing and reforming (...) society in which justice is conceived both as a principle of government, a principle of social conduct and one of the essential virtues, or a ‘moral sense’ that everyone must possess, while, in practice, Confucian justice will put forward the imperatives of retributive justice. This, despite its philosophical aversion for sanctions and for what upsets harmony. (shrink)

Psychosis is associated with distorted perceptions and deficient bottom-up learning such as classical fear conditioning. This has been interpreted as reflecting imprecise priors in low-level predictive coding systems. Paradoxically, overly strong beliefs, such as overvalued beliefs and delusions, are also present in psychosis-associated states. In line with this, research has suggested that patients with psychosis and associated phenotypes rely more on high-order priors to interpret perceptual input. In this behavioural and fMRI study we studied two types of fear (...) learning, i.e., instructed fear learning mediated by verbal suggestions about fear contingencies and classical fear conditioning mediated by low level associative learning, in delusion proneness—a trait in healthy individuals linked to psychotic disorders. Subjects were shown four faces out of which two were coupled with an aversive stimulation while two were not in a fear conditioning procedure. Before the conditioning, subjects were informed about the contingencies for two of the faces of each type, while no information was given for the two other faces. We could thereby study the effect of both classical fear conditioning and instructed fear learning. Our main outcome variable was evaluative rating of the faces. Simultaneously, fMRI-measurements were performed to study underlying mechanisms. We postulated that instructed fear learning, measured with evaluative ratings, is stronger in psychosis-related phenotypes, in contrast to classical fear conditioning that has repeatedly been shown to be weaker in these groups. In line with our hypothesis, we observed significantly larger instructed fear learning on a behavioural level in delusion-prone individuals compared to non-delusion-prone subjects. Instructed fear learning was associated with a bilateral activation of lateral orbitofrontal cortex that did not differ significantly between groups. However, delusion-prone subjects showed a stronger functional connectivity between right lateral orbitofrontal cortex and regions processing fear and pain. Our results suggest that psychosis-related states are associated with a strong instructed fear learning in addition to previously reported weak classical fear conditioning. Given the similarity between nocebo paradigms and instructed fear learning, our results also have an impact on understanding why nocebo effects differ between individuals. (shrink)

Reasoning with conditionals is often thought to be non-monotonic, but there is no incompatibility with classical logic, and no need to formalise inference itself as probabilistic. When the addition of a new premise leads to abandonment of a previously compelling conclusion reached by modus ponens, for example, this is generally because it is hard to think of a model in which the conditional and the new premise are true.

Using a classical conditioning technique, this study investigated whether nonconscious associative learning could be indexed by event-related brain activity . There were three phases. In a preconditioning baseline phase, pleasant and unpleasant facial schematics were presented in awareness . A conditioning phase followed, in which stimuli were presented outside awareness , with an unpleasant face linked to an aversive shock and a pleasant face not linked to a shock. The third, postconditioning phase, involved stimulus presentations in (...) awareness . Evidence for acquisition of a conditional response was sought by comparing suprathreshold pre- and postconditioning phases, as well as in the subthreshold conditioning phase itself. For the pre-postconditioning phase analyses, significant ERP component differences differentiating CS+ and CS− were observed for N1, P2, and especially P3. For the conditioning phase, significant differences were observed in the 100–400 ms. post-stimulus region reflecting a CS+ processing negativity. Brain activity does indeed index the acquisition of a conditional response to subthreshold stimuli. Associative learning can occur outside awareness. (shrink)

We study the conditions under which increasing risk raises the optimal control variable when the budget constraint is nonlinear. In contrast to the case when the budget constraint is linear, nonlinearities alter the risk attitudes of the economic agent; that is, the agent’s risk behavior is driven by the interaction between the shape of the utility function and the shape of the budget constraint. This paper complements the classical literature with linear payoff functions in two important ways. First, we (...) derive necessary and sufficient conditions for unambiguous comparative statics of changes in risk when the budget constraint is nonlinear. Second, we highlight the critical role of the coefficients of technological improvement and cross-prudence in technology derived from the nonlinear budget constraint in a similar form to that in which the coefficient of relative risk aversion and the coefficient of relative prudence are derived from the utility function. We show several applications of this theory, including the worker’s decision to work in-person during a pandemic. (shrink)

Using a classical conditioning technique, this study investigated whether nonconscious associative learning could be indexed by event-related brain activity . There were three phases. In a preconditioning baseline phase, pleasant and unpleasant facial schematics were presented in awareness . A conditioning phase followed, in which stimuli were presented outside awareness , with an unpleasant face linked to an aversive shock and a pleasant face not linked to a shock. The third, postconditioning phase, involved stimulus presentations in (...) awareness . Evidence for acquisition of a conditional response was sought by comparing suprathreshold pre- and postconditioning phases, as well as in the subthreshold conditioning phase itself. For the pre-postconditioning phase analyses, significant ERP component differences differentiating CS+ and CS− were observed for N1, P2, and especially P3. For the conditioning phase, significant differences were observed in the 100–400 ms. post-stimulus region reflecting a CS+ processing negativity. Brain activity does indeed index the acquisition of a conditional response to subthreshold stimuli. Associative learning can occur outside awareness. (shrink)

Most phobias are focussed on a small number of fear-inducing stimuli (e.g., snakes, spiders). A review of the evidence supporting biological and cognitive explanations of this uneven distribution of phobias suggests that the readiness with which such stimuli become associated with aversive outcomes arises from biases in the processing of information about threatening stimuli rather than from phylogenetically based associative predispositions or “biological preparedness.” This cognitive bias, consisting of a heightened expectation of aversive outcomes following fear-relevant stimuli, generates (...) and maintains robust learned associations between them. Some of the features of such stimuli which determine this expectancy bias are estimates of how dangerous they are, the semiotic similarity between them and their aversive outcomes, and the degree of prior fear they elicit. Ontogenetic and cultural factors influence these features of fear-relevant stimuli and are hence important in determining expectancy bias. The available evidence does not exclude the possibility that both expectancy biases and specific evolved predispositions coexist, but the former can explain a number of important findings that the latter cannot. (shrink)

This polemical work presents to the English-speaking world one of the most original philosophical thinkers to have emerged within post-war Europe. Sebastiano Timpanaro is an Italian classical philologist by training, an author of scholarly studies on the nineteenth-century poet Leopardi, and a Marxist by conviction. With great force and wit, On Materialism sets itself against what it sees as the virtually universal tendency within western Marxism since the war, to dissociate historical materialism from biological or physical materialism. Whereas the (...) philosophical legacy of the later Engels has been decried by most prominent Marxists since the 1920s, Timpanaro eloquently defends its essential purpose and relevance, by unfashionably re-emphasising the permanent weight of nature within history. In doing so, he returns to the heritage of Lucretius and Leopardi, and argues for a more consistent materialism that is at once more pessimistic and more hedonistic than any other contemporary version of Marxism. Timpanaro emphasises the insuperable limits of frailty and mortality as unalterable conditions of society whose transformation is the goal of revolutionary socialism. Timpanaro vigorously attacks what he regards as the widespread entente between a diluted Marxism and a fashionable idealism in the west, whether in the form of an “existentialist” or a “structuralist” union of the two. The aversion of the former to the work of Darwin and Engels receives a spirited refutation, no less than the indulgence of the latter towards the work of Saussure or Levi-Strauss. A special introduction written for this English edition deals with the phenomenon of the recent revival of “vulgar materialism” in the Anglo-Saxon world, in the fields of psychology and anthropology, and its relationship to racism. On Materialism will be one of the central focuses of cultural and intellectual controversy within and beyond Marxism in the next decade. (shrink)