Cross-modality contrast: Exteroceptive context habituation enhances taste neophobia and conditioned taste aversions

The relationship between absolute and relative stimulus novelty was examined within the context of the conditioned taste aversion paradigm in which the relative novelty of the conditioned interoceptive stimulus was manipulated by differential exteroceptive context habituation. Rats received similar isolation histories but either 5 or 30 days of habituation to the test environment prior to treatment. One group was administered lithium chloride following saccharin consumption, a second group was administered isotonic saline following saccharin consumption, and a third group was administered saline after water consumption. The animals habituated for 30 days exhibited greater conditioned avoidance and greater neophobic avoidance of saccharin than did animals habituated for only 5 days. The results are interpreted in terms of a cross-modality stimulus contrast effect which implicates context habituation as an important parameter of both taste neophobia and taste aversion learning.     

Preweanling handling influences open-field behavior,but not negative contrast or sucrose neophobia

Handling of preweanlings (Days 2–15) had substantial effects on the open-field behavior of rats when tested as adults. In general, handled rats reared more, ambulated more, and defecated less than nonhandled rats. However, the handling manipulation had no effect on the degree of negative contrast that occurred when rats were shifted from 32% to 4% sucrose. Experiments 2 and 3 showed that preweaning handling did not influence sucrose neophobia in two different test situations. These data, in conjunction with those of other studies, suggest that preweaning handling may have powerful but limited effects on adult behavior, and that these effects are probably not best characterized in terms of global concepts such as emotionality.     

Partial reward,the negative contrast effect,and incentive averaging

A total of 169 rats, distributed across six experiments, received training in a straight runway with a 5-min intertrial interval. A variety of shifts in reward schedules, to and from partial reward, were employed to assess the effects of partial reward on the successive negative contrast effect. The results were seen as supportive of an incentive averaging approach to partial reinforcement.     

Effects of pretraining on conditioning-enhanced neophobia: Evidence for separable mechanisms of neophobia and aversion conditioning

In two experiments, rats (n = 228) received pretraining access to a distinctive novel flavor (saline) followed by aversion conditioning to a different novel conditioned stimulus (CS) (saccharin). Then the rats were tested for aversion to the CS (saccharin) or for conditioning-enhanced neophobia to a third novel flavor (casein hydrolysate). Pretraining access to a distinctive novel flavor that differed from the CS reliably reduced the magnitude of conditioning-enhanced neophobia to casein, but did not reliably affect conditioned aversion effects to the CS. Pretraining access to the CS reduced aversion effects to the CS and reduced postconditioning neophobia to casein to the performance level shown by ingestion-toxin controls. Results were consistent with the view (Braveman & Jarvis, 1978) that conditioned aversion and neophobia may be independent phenomena with separable underlying mechanisms.     

Preexposure to feeding-related stimuli reduces neophobia

Rats that were preexposed to novel solutions or to novel feeding environments showed reduced neophobic responses when presented with a familiar solution in a novel container or with a novel flavored solution in a familiar container, respectively. Preexposure to novel solutions also appeared to reduce emotional reactivity as measured in the open field.     

Conditioned fear and neophobia following inescapable shock

Lick-suppression tests were used in seven experiments to assess the transsituational transfer of fear in the learned helplessness paradigm. Two sources of fear combined to suppress test drinking in inescapably shocked rats. A situational odor was strongly associated with shock pretreatments and mediated the transfer of conditioned fear during testing. Fear of the pretreatment odor was greater following inescapable shock than after escapable shock or restraint. This conditioned suppression was retained for at least 72 h after pretreatment. Neophobia was enhanced as a second, nonassociative reaction to inescapable shock. Unconditioned fear was augmented by a novel odor in the test context, but otherwise was weak and dissipated within 72 h. However, neophobia was necessary for differential conditioned suppression in inescapably shocked rats. The pretreatment odor elicited fear only when tested in a novel context. Initial habituation to the test apparatus reduced conditioned fear. These data provide additional evidence for odor-mediated transfer of helplessness. Conditioned fear and neophobia are discussed in relation to recent anxiety interpretations of the phenomenon.     

Independence of neophobia and taste aversion learning

Animals were presented with (1) one solution which differed from that of the test solution, (2) a series of distinctly flavored solutions whose flavors differed from that of the test solution, or (3) with a flavored solution whose flavor was the same as that of the test solution. When animals received the solution whose flavor was the same as that of the test solution prior to a test for neophobia and prior to a conditioning trial, neophobia was reduced and aversions were weakened. However, when animals received a solution or a series of solutions whose flavors differed from that of the test solution, neophobia was reduced but conditioned aversions were unaffected. Presentations of solutions that differed from the test solution following aversion formation left the association between the taste of the test solution and the effects of the aversion-inducing treatment intact. In a final experiment it was discovered that neophobia was reduced as much when animals drank solutions whose flavors changed every third day as when they drank the same solution throughout testing.     

Effects of distractor familiarity on habituation of neophobia

When the first presentation of a neophobic flavor is immediately followed by a distractor flavor, habituation of the neophobic response is typically attenuated. This is manifested by the fact that neophobia is still shown to the target flavor on its second presentation. Three experiments investigated the prediction that this effect will occur only for novel, but not familiar, distractor solutions. Experiments 1 and 2 found that, contrary to this prediction, both novel and familiar distractors can attenuate the habituation of a neophobic response. In Experiment 3, however, when the distractor was made very much more familiar, it lost its ability to interfere with the habituation of neophobia to the target solution. These results are discussed in terms of Wagner’s (1981) theory of habituation.     

Anticipation of incentive gain

In four experiments, the once daily availability of saccharin (.15%) preceded the availability of sucrose (32% or 2%). Experiment 1 showed that the intake of saccharin was reduced when it preceded 32% sucrose but not when it preceded 2% sucrose, as compared with saccharin-alone conditions. Experiment 2 showed that less saccharin was consumed when the saccharin preceded sucrose by 5 min than when there was a 30-min intersolution interval. Experiment 3 replicated this finding and showed that the presentation of the two solutions through the same or different access holes in the apparatus was not relevant to the result. Experiment 4 showed that there was an inverse relationship between saccharin intake and the length of the intersolution interval in the range of 1 to 30 min. These data were interpreted to indicate that the animals learn the predictive relationship between the saccharin and sucrose solutions and that the intake of the saccharin is reduced by an anticipatory contrast mechanism—a mechanism that may have restricted temporal parameters.     

The role of amount consumed in flavor preexposure effects and neophobia

Rats received either a small or a large amount of a novel saccharin solution prior to a conditioning episode in which the saccharin flavor was paired with lithium-induced toxicosis. When the time between the preexposure and the conditioning episode was 3.5 h, both the small and large amounts of saccharin decremented conditioning. However, when the time between the preexposure and the conditioning episode was 23.6 h, only the consumption of a large amount of saccharin decremented conditioning. In a second experiment, rats received either a short or a long exposure to the novel saccharin solution and were then given a choice test between the saccharin and water. Rats given the choice test immediately following their preexposure to saccharin avoided consuming it. If they received the choice test 4 h later, they consumed more of the saccharin irrespective of the length of the preexposure. In contrast, when they were given a choice test 24 h after the preexposure, only rats that had received a long preexposure displayed a significant preference for the saccharin. The present results demonstrate that the flavor preexposure effect and the attenuation of neophobia are both determined by the time between preexposure to the novel flavor and the conditioning episode or choice test and the amount of preexposure to the novel flavor. These findings are discussed in relation to the information-processing model developed by Wagner (1976, 1978) and are used to provide an account, in terms of this model, of the delay-gradient seen in flavor-aversion learning.     

Incentive contrast produced by deprivation shifts

Deprivation shifts, using conditions analogous to those which produce strong incentive contrast when reward quantity is changed (extended preshift training, short interval from the last preshift trial to the first postshift trial, large preshift differences in deprivation) resulted in contrast of runway speed and choice behavior. In the first experiment, a downshift of hunger during rats’ runway training produced a slow lessening of speed below that of a group trained continually at low hunger. In the second experiment, rats were trained to traverse a runway to one food-containing goalbox when very hungry and to another, distinctively different food-containing goalbox when not very hungry. The rats were next given a series of choice trials between the two goalboxes. There was a brief preference for the high-hunger goalbox, followed by a preference for the low-hunger goalbox. The results of the second experiment suggest that deprivation affects the strength of conditioning of a cue-reinforcer expectancy, while the slow development of contrast in the first experiment indicates that deprivation also affects the development of either habit strength or a response-reinforcer expectancy.     

The role of incentive learning in instrumental outcome revaluation by sensory-specific satiety

Hungry rats were trained to perform two instrumental actions, one for salt- and the other for lemonflavored polycose solution. When they were sated on one of these two outcomes by prefeeding immediately prior to a choice extinction test, the action trained with the prefed solution was performed less than the other action. The subsequent experiments examined the role of incentive learning in this specific satiety-induced outcome revaluation effect. The second experiment demonstrated that the experience of consuming a flavored polycose solution to satiety enabled the state induced by polycose consumption to control the devaluation of the flavored outcome. By contrast, the third study found that, although devaluing the prefed outcome, specific-satiety treatments could induce a relative inflation in the incentive value of other food outcomes. The final two studies demonstrated an increased outcome-devaluation effect in instrumental performance when these devaluation and revaluation effects were combined. Taken together, these studies demonstrate that specific satiety treatments produce changes in outcome value that depend upon incentive learning.     

语文教学中的多元激励策略

一切内心要争取的条件、愿望、动力都构成了对人的激励。人的一切行动都是由某种动机引起的,动机是一种精神状态,它对人的行动起激发、推动、加强的作用。在语文教学中顺应学生的心理发展特点,采用合理的激励策略,可以调动学生的积极性,让学生主动学习、乐于学习、勤于探索,有自信心、自尊心和上进心。在教学中,采用多元化、多样性的激励方式有助于提高教学质量,达到更好的教学目的。     

Poison-induced neophobia in rats: Role of stimulus generalization of conditioned taste aversions

Rats repeatedly injected with lithium chloride were subsequently tested drinking novel and familiar solutions of both casein hydrolysate and vinegar. Injections in the absence of edibles result in only a small, and sometimes not reliable, increased avoidance of the novel casein and vinegar solutions. In contrast, if subjects acquired an aversion to saccharin as a result of the lithium injections, this learned aversion generalized to casein hydrolysate, with the generalization greatly enhanced by novelty of the casein flavor. However, the saccharin aversions did not generalize to the novel vinegar solution nearly as much as to the novel casein flavor. These results suggest that previous observations of poison-induced neophobia were probably in part a result of the stimulus generalization of conditioned taste aversions and that in addition to test stimulus novelty some other factor, such as stimulus salience or similarity to the conditioned aversive flavor, is also involved in the generalization of learned taste aversions.     

企业激励管理机制探究

在新的时代背景下,面对越来越激烈的市场竞争形势,企业必须加大创新和改革的力度,注重人才在企业的发展建设中所发挥的重要作用,建立并完善企业的人才激励机制,充分挖掘员工的无限潜能,激发员工的工作热情,全面提升员工的工作效率,为企业创造更多的经济效益和社会价值,推动企业的发展和进步。本文主要针对企业激励管理机制方面的问题进行分析和探讨,以供参考和借鉴。     

Attenuated and enhanced neophobia in the taste-aversion “delay of reinforcement” effect

Learning & Behavior - Rats were made ill immediately or 6 h after drinking either familiar tap water or a novel .1% saccharin solution. Control animals were given sham treatments immediately...     

中国古代激励思想举要

"士为知己者死"的情感激励法 这种激励的方法在于鼓励下属并统一其所思所想所为。我们知道,人的行为是由人的意识意志指导的行为。意识在先,行为在后,有了一定的意识,才能相应产生一定的行为。而人的意识又是不断发展的。这就要求管理者在实施管理的过程中不断设计、构造、维持、协调、诱导他人意志行为的情境,以期     

Negative incentive steering in a policy network

In this article the process of developing a policy for the recent comprehensive retrenchment operation in the Dutch university system is analysed from a theoretical point of view on decisionmaking. The article especially addresses the question whether some empirical evidence can be found for the rationalist view of collective decision-making, which states that a process of social communication should eventually lead to a unanimous and rational consensus concerning the selection of the optimal policy.The actual analysis concerns the way a retrenchment policy has been developed in a process of social communication between the most important actors: the Minister of Education and Science and the thirteen Dutch universities. It is assumed that the various communicative linkages between these actors can be interpreted as a policy network in which both governmental and non-governmental actors operate.The article concludes that in the Dutch university policy-network a complicated balance of interdependencies exists and that several sub-networks can be distinguished. It is also concluded that the Minister, while recognizing the interdependencies in the network, was able to use a special kind of (negative) incentive, inducing the universities to act as he wished.This negative incentive steering, however, also persuaded the universities to go to the utmost in their consultation efforts, thus trying to reach the rationalist ideal of collective decision-making. The final conclusion therefore is that the rationalist view of collective decision-making does not appear to be unrealistic. The article ends with a warning against a common mistake made regarding the normative appearance of the rationalist perspective.The case of the policy development process concerning the retrenchment operation in the Dutch university system in 1982 and 1983.     

简论中国古代激励思想

中国古代激励思想的产生,与独特的入世精神、"重义轻利"、注重和谐的"中庸之道"的历史文化背景有关,激励思想有情理激励、管理激励、伦理激励和法理激励等几个方面.文章对中国古代激励思想作了简要评价.