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As a group, cigarette smokers exhibit blunted subjective, behavioral, and neurobiological responses to nondrug incentives and rewards, relative to nonsmokers. Findings from recent studies suggest, however, that there are large individual differences in the devaluation of nondrug rewards among smokers. Moreover, this variability appears to have significant clinical implications, since reduced sensitivity to nondrug rewards is associated with poorer smoking cessation outcomes. Currently, little is known about the neurobiological mechanisms that underlie these individual differences in the responsiveness to nondrug rewards. Here, we tested the hypothesis that individual variability in reward devaluation among smokers is linked to the functioning of the striatum. Specifically, functional magnetic resonance imaging was used to examine variability in the neural response to monetary outcomes in nicotine-deprived smokers anticipating an opportunity to smoke—circumstances found to heighten the devaluation of nondrug rewards by smokers in prior work. We also investigated whether individual differences in reward-related brain activity in those expecting to have access to cigarettes were associated with the degree to which the same individuals subsequently were willing to resist smoking in order to earn additional money. Our key finding was that deprived smokers who exhibited the weakest response to rewards (i.e., monetary gains) in the ventral striatum were least willing to refrain from smoking for monetary reinforcement. These results provide evidence that outcome-related signals in the ventral striatum serve as a marker for clinically meaningful individual differences in reward-motivated behavior among nicotine-deprived smokers.  相似文献   

3.
Jonathan Tallant 《Synthese》2013,190(15):2959-2980
This paper is an exploration of the role of intuition in physics. The ways in which intuition is appealed to in physics are not well understood. To the best of my knowledge, there is no analysis of the different contexts in which we might appeal to intuition in physics, nor is there any analysis of the different potential uses to which intuition might be put. In this paper I look to provide data that goes some way to giving a sense of the different contexts in which intuition is appealed to in physics. As I note in the conclusion, there is still much work to be done but I hope that the work here provides us with a first step in the journey to properly understand the use to which intuitions are put in physics and science more generally.  相似文献   

4.
The purpose of this study was to investigate the changes in value orientations of Turkish youth from 1989 to 1995 and to see how changes in Turkish society affected the value orientations of Turkish youth. The Rokeach Value Survey (RVS; M. Rokeach, 1973) was administered in Ankara to 289 young people in 1989, to 318 young people in 1992, and to 397 young people in 1995. Results indicated that the value orientations of the Turkish youth in 1989 underwent major changes that were manifested in 1992, toward a more competitive and individualistic orientation. Similar characteristics were reflected in the value priorities of the young people in 1995, which indicates that values are modified to fit the changes the society experiences.  相似文献   

5.
Male songbirds learn to produce song within a limited phase early in life; however they continue to learn to recognize songs in adulthood. Studies looking at Zenk activation after exposure to songs learned early in life for song production and songs learned in adulthood show opposite patterns of activation, suggesting distinct neural mechanisms may be involved in these two forms of learning. In this study, we look at IEG Zenk activation in auditory regions NCM and CMM of song sparrows (Melospiza melodia) to see whether recent exposure to song in adulthood leads to greater or decreased Zenk activation upon hearing that song versus a novel song. We found significantly lower activation in birds exposed to previously heard songs versus novel songs in vNCM but not dNCM, though further analysis suggest an overall trend in NCM. We found no significant difference in the amount of activation to previously heard songs vs. novel songs in CMM. These results support previous findings suggesting that activation is reduced to learned stimuli; we discuss possible implications of these findings in relation to song production learning early in life and song recognition learning in adulthood.  相似文献   

6.
Prefrontal cortex provides both inhibitory and excitatory input to distributed neural circuits required to support performance in diverse tasks. Neurological patients with prefrontal damage are impaired in their ability to inhibit task-irrelevant information during behavioral tasks requiring performance over a delay. The observed enhancements of primary auditory and somatosensory cortical responses to task-irrelevant distractors suggest that prefrontal damage disrupts inhibitory modulation of inputs to primary sensory cortex, perhaps through abnormalities in a prefrontal-thalamic sensory gating system. Failure to suppress irrelevant sensory information results in increased neural noise, contributing to the deficits in decision making routinely observed in these patients. In addition to a critical role in inhibitory control of sensory flow to primary cortical regions, and tertiary prefrontal cortex also exerts excitatory input to activity in multiple sub-regions of secondary association cortex. Unilateral prefrontal damage results in multi-modal decreases in neural activity in posterior association cortex in the hemisphere ipsilateral to damage. This excitatory modulation is necessary to sustain neural activity during working memory. Thus, prefrontal cortex is able to sculpt behavior through parallel inhibitory and excitatory regulation of neural activity in distributed neural networks.  相似文献   

7.
通过两个实验考查了非临床抑郁者未来想象的异常是否受到个人目标相关性的调节。实验1采用未来想象任务, 实验2采用可能性评估范式, 两个实验一致发现, 抑郁倾向者想象未来积极事件的异常, 受到了与个人目标相关性的调节:相对于非抑郁倾向者, 抑郁倾向者对未来与个人目标相关的积极事件的预期减弱, 而对未来与个人目标无关的积极事件的预期则没有表现出异常; 同时还发现, 抑郁倾向者表现出了对未来消极预期的普遍增强, 不受与个人目标相关性的影响。  相似文献   

8.
Serotonergic and opiate interactions in the modulation of drug- and environmental-induced analgesia were assessed in 6-day-old Sprague-Dawley-derived rat pups using tail-flick testing procedures. In these experiments the serotonergic antagonist metergoline was observed to attenuate both the analgesia induced by the opiate agonist morphine and the analgesia induced by isolation from siblings and the dam, an environmental manipulation which has previously been shown to be associated with increases in opiate activity. In contrast, the opiate antagonist naloxone was observed to be ineffective in blocking not only analgesia induced by the serotonergic agonist quipazine, but also analgesia induced by long-term deprivation from the dam and food, a manipulation that has been previously reported to induce increases in serotonergic utilization. These results suggest that in the neonate, as in the adult, the serotonergic modulation of nociception appears to occur "downstream" from the opiate systems serving to regulate nociception following both drug- and environmental-induced alterations in pain sensitivity. Analgesia induced by long-term deprivation from food and the dam appears to be strongly related to increases in serotonergic activity and relatively unaffected by opiate antagonism, whereas analgesia induced by isolation from siblings and the dam may be related to increases in opiate activity, but modulated by serotonergic systems serving to regulate pain responsivity. Thus alterations in the environment, mediated at least in part by alterations in opiate and serotonergic activity, appear to play an important role in influencing the sensitivity of the neonate to pain stimuli.  相似文献   

9.
This research examines the effects of relationship type (close vs. business), a personality variable (dispositional communal orientation), and the interaction of these two variables on individuals’ willingness to express emotions to relationship partners. Results supported our predictions that (a) people are willing to express more emotion in relationships likely to be high in communal strength than in relationships likely to be low in communal strength, (b) individuals high in communal orientation are willing to express more emotion than those who are low in communal orientation, and (c) relationship type and communal orientation interact to influence willingness to express two emotions that reveal weakness and vulnerability (fear and anxiety). Specifically, communal orientation had little effect on willingness to express fear and anxiety in business relationships, whereas high relative to low communal orientation was associated with willingness to express more fear and anxiety within close relationships.  相似文献   

10.
ne important class of actions concerns tasks. Questions may be raised about whether we have succeeded or failed to do what we were trying to do. Not all the things we call actions are open to considerations of such success or failure. And questions of succeeding or failing are not raised solely about what we may have been trying to do. The paper attempts to classify various ways in which one may fail in an action; the array that results is explored in terms of evaluations rendered, responsibility, character, deliberate decision, and the like. The analysis of failing in what one has tried to do is made central. To be said to be trying to do something, one must have done the requisite things that constitute trying to do something and not to have succeeded yet in doing what one may have tried to do. “Trying to succeed”; in doing something is a redundant expression except for special cases; and though one may decide to try to do something, one cannot decide to succeed in this. One may actually succeed in doing what one has tried to do but one cannot deliberately succeed. Further distinctions are made between trying to do something and wishing to do something and believing that one is trying to do something; also, between failing in what one has tried to do, failing to try, failing to do something without failing in what one has tried to do, and failing to do something in respects in which one could never be said to have tried to do it.  相似文献   

11.
It is commonly assumed that persons who hold abortions to be generally impermissible must, for the same reasons, be opposed to embryonic stem cell research [ESR]. Yet a settled position against abortion does not necessarily direct one to reject that research. The difference in potentiality between the embryos used in ESR and embryos discussed in the abortion debate can make ESR acceptable even if one holds that abortion is impermissible. With regard to their potentiality, in vitro embryos are here argued to be more morally similar to clonable somatic cells than they are to in vivo embryos. This creates an important moral distinction between embryos in vivo and in vitro. Attempts to refute this moral distinction, raised in the recent debate in this journal between Alfonso Gómez-Lobo and Mary Mahowald, are also addressed.  相似文献   

12.
To prevent youth violence, the GREAT Families program was implemented with a selective sample of 1,196 families of sixth-grade children from low-income schools in 4 cities making the transition to adolescence. To assess intervention effects, we used pre- and posttest data to estimate a structural model to test the hypothesis that random assignment to the intervention would predict changes in parenting practices, which in turn would predict changes in exposure to violence (i.e., a mediational model). We found that participation in GREAT was significantly related to changes in parenting practices and these changes significantly predicted changes in violence exposure. Furthermore, adolescents who reported greater increases in exposure to violence also tended to experience greater decreases in parental monitoring, discipline, and involvement. Implications for future research and prevention efforts are discussed.  相似文献   

13.
The ability of stress to initiate or reactivate an inflammatory process seems to depend on an individual's susceptibility to stressful stimuli. The aim of this study was to establish whether previous inflammation alters the response to stress in Sprague-Dawley rats, a strain not especially susceptible to stressful stimuli. Stress exposure was performed in rats treated with indomethacin, to induce cyclic intestinal inflammation, during the inactive phase of inflammation. Both control and indomethacin-treated rats submitted to stress showed a decrease in body weight gain and blood leukocyte levels, as well as an increase in fecal pellet output. The increase in intestinal mucosal mast cell count induced by stress was similar in both groups of animals. Moreover, no differences were observed between control and indomethacin-treated rats in the degree of bacterial translocation and myeloperoxidase levels after stress exposure. Despite these similarities, differences between groups were observed in inducible nitric oxide synthase (iNOS) mRNA expression. Although ileal iNOS mRNA expression was inhibited in healthy rats submitted to stress, stress failed to modify this parameter in indomethacin-treated rats. As iNOS is another inflammatory marker, our results may allow the possibility that a previous intestinal inflammation could change the intestinal susceptibility to stress. Whether these differences in ileal iNOS expression can be indicative of a possible change in the predisposition to develop an intestinal inflammatory reaction in response to stress in Sprague-Dawley rats remains to be elucidated.  相似文献   

14.
Structured parent training has been proven to be effective in reducing disruptive behavior problems (DBP) in children. Most of the programs that are used in Sweden have their origin in North America, and there is an ongoing debate over the transferability to Sweden of manual-based programs developed in other contexts. The goal of the present study was to study effectiveness of the Incredible Years parent-training program (IY), developed in the US, in regular clinical work in Sweden, using a randomized controlled design. Parents of 62 four to eight-year-old children diagnosed with Oppositional Defiant Disorder participated in the study. Parents of 38 children were assigned to parent training (PT) and 24 to a waiting list (WL). The results indicate that the IYS retains the positive effects on children's disruptive behavior problems when translated and transferred to Swedish. There was a statistically significant difference in reduction of DBP in children between the groups in favor of the PT. The improvement in the PT group was sustained at the one-year follow-up. The improvement also, at least to some extent, generalized over time to the school context. There was also a statistically significant difference in mothers' report of pre to post change in parenting alliance between the PT and WL groups. The IYS program was appreciated and well received by the participating mothers.  相似文献   

15.
Individuals differ in the extent to which their vulnerability to anxiety is reduced by psychological therapy. However, the cognitive basis for such individual differences is still poorly understood. To test a cognitive account of differences in anxiety reduction in response to treatment, the present study examined individuals undergoing group therapy for social anxiety disorder. We assessed whether differences in their readiness to adopt selective attentional processing in response to an experimental contingency predicted positive changes in a range of anxiety measures in response to treatment. Findings were consistent with the position that readiness to alter attentional processing bias may underpin individual differences in the tendency to respond to positive experiential conditions, such as group therapy, by reducing anxiety vulnerability.  相似文献   

16.
Barbary macaques (Macaca sylvanus) utter "shrill barks" in response to disturbances in their surroundings. In some cases, the majority of group members react by running away or climbing up a tree. In many other instances, however, group members show no overt reaction to these calls. We conducted a series of playback experiments to identify the factors underlying subjects' responses. We presented calls given in response to dogs that had elicited escape responses and calls that had failed to do so. We also presented calls given in response to snakes and to the observer approaching the sleeping-trees at night. An acoustic analysis of the calls presented in the playback experiments (electronic supplementary material, audioclip S1) revealed significant differences among calls given in response to dogs, the observer approaching at night, and snakes. However, the analysis did not detect any differences between calls given in response to dogs that were related to whether or not they had elicited escape responses in the first place. Correspondingly, after playback of calls given in response to dogs, we observed no difference in subjects' responses in relation to whether or not the calls had initially elicited escape responses. Subjects showed startle or escape responses significantly more often after playbacks of calls given in response to dogs than after calls given in response to observers. Playbacks of calls given in response to snakes failed to elicit specific responses such as standing bipedally or scanning the grass. Although these findings may imply that responses depend on the external referent, they also indicate that there is no clear-cut relationship between the information available to the listeners and their subsequent responses. This insight forces us to extend current approaches to identifying the meaning of animal signals. Accepted after revision: 15 May 2001 Electronic Publication  相似文献   

17.
Resilience is a term used to describe relative resistance to psychosocial risk experiences. There is abundant evidence that there is enormous variation in children's responses to such experiences but research to determine the processes underlying the variations needs to take account of several crucial methodological issues. The findings emphasize that multiple risk and protective factors are involved; that children vary in their vulnerability to psychosocial stress and adversity as a result of both genetic and environmental influences; that family-wide experiences tend to impinge on individual children in quite different ways; that the reduction of negative, and increase of positive, chain reactions influences the extent to which the effects of adversity persist over time; that new experiences which open up opportunities can provide beneficial 'turning- point' effects; that although positive experiences in themselves do not exert much of a protective effect, they can be helpful if they serve to neutralize some risk factors; and that the cognitive and affective processing of experiences is likely to influence whether or not resilience develops. The implications of these findings for family therapy are considered in terms of the need for therapists to look carefully at the ways in which different risk factors interact; to assess and take account of individual differences in susceptibility; to consider the extent to which risk factors impinge on the individual and, in that connection, to note the importance of patterns of social interaction outside as well as inside the family; to appreciate the role of both the peer group and individual characteristics in the development of negative and positive chain reactions; and to pay attention to the ways in which individuals process their experiences.  相似文献   

18.
Taste sensitivity for sodium chloride in solution and sensitivity and preference for sodium chloride in bread were measured in 14 male patients undergoing hemodialysis. There was an increase in sensitivity to salt taste following dialysis only when assessed using the bread samples. Patients on a lower sodium diet were more sensitive to salt taste in bread. Although the taste changes were not related to the decreases in serum sodium or to copper, greater increases in sensitivity were related to greater increases in serum zinc during dialysis.  相似文献   

19.
The self as a psychological construct, and the self in relation to the other has been discussed in psychological and sociological literature for decades, but not much attention has been given to the psychological development of the self in relation to the social construction of prejudice. The primary aim of this article is to explore the self in prejudice and thus the psychological processes involved in the development of self within the social context. Consequently, the aim is to explore the self in the construction and expression of prejudice from both a social and psychological approach, and to explain selfhood influences at the individual, group and community levels. I use the conceptual framework of Kohut's self psychology as a lens to present the development of the self and thus the idea of the development of the self in relation to the other. In such exploration of self in prejudice, I present some of my ideas which include prejudice as an outcome of self-definition in the context of the other, as well as linking self in prejudice and group dynamics to attachment theory and the notion of “selfgroup’ in terms of overidentification with the in-group. While the social and the psychological in terms of the development of the self cannot be separated, I have therefore attempted to merge at some point the two bodies of thought in relation to the self in prejudice.  相似文献   

20.
In two experiments, hungry rats were given instrumental lever-press training for an appetitive reinforcer and, in addition, were exposed to another type of food which was not contingent on lever pressing. In the first experiment, exposure to each type of food was on separate days, whereas in the second experiment rats were exposed to each type of food in strict alternation within each session. Subsequently, a food aversion was conditioned to the reinforcer for the experimental group and to the non-contingent food for the control group. In both experiments, animals with an aversion to the reinforcer responded less in an extinction test than animals with an aversion to the non-contingent food. Subsequent reacquisition tests confirmed that the aversion to the non-contingent food in the control group was of comparable strength with that to the reinforcer in the experimental group. The results were discussed in terms of whether the reinforcer is encoded in the associative structure set up by exposure to an instrumental contingency.  相似文献   

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