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51.
As the population of older adults continues to rise, psychologists along with other behavioral and social scientists have shown increasing interest in this age group. Although behavior analysts have contributed to research on aging, the focus has been on applications that remedy age-related deficits, rather than a concern with aging as a developmental process. In particular, there has been little interest in the central theoretical questions that have guided gerontologists. How does behavior change with advancing years, and what are the sources of those changes? We consider the possibility that this neglect reflects the long-standing commitment of behavior analysts to variables that can be experimentally manipulated, a requirement that excludes the key variable—age itself. We review the options available to researchers and present strategies that minimize deviations from the traditional features of behavior-analytic designs. Our comments are predicated on the view that aging issues within contemporary society are far too important for behavior analysts to ignore.  相似文献   
52.
The present study examined whether gender differences in affiliative aspects (collaboration and cooperation) of dyadic conversations occur because girls are more oriented than boys toward goals focused on others. Preadolescents (11-13 years old; 51 boys, 53 girls) worked with a same- or an other-gender peer on a 4-week-long creative-writing task at school. Dyadic conversations and goals were assessed twice. High-affiliation conversations and mutual-participation goals were more prevalent in female than in male and mixed-gender dyads. Mutual-participation goals mediated gender differences in high-affiliation conversations. Control and task-performance goals did not differ by dyad gender. In mixed-gender dyads, conversation strategies and goals did not differ by gender. Implications of goals for understanding gender differences and similarities in conversations are discussed.  相似文献   
53.
Conclusion Robert Heinlein, author of Stranger in a Strange Land as well as countless other science fiction stories, once claimed that "The sole thing achieved by any privacy law is to make the bugs smaller." Heinlein may be correct, but that travesties will happen does not sanction them—and maybe we will invent bugs to root out and foil other bugs. I have argued for individual privacy rights or rights to control sensitive personal information. The explosion of digital technology has made possible severe violations of individual privacy by corporations, news agencies, and the government. If I am correct about all of this, one commonly used "public interest" argument given for limiting privacy rights has been undermined. It is also far from true to claim that the prevalence of strong encryption technology will lead to disaster. While I do not adhere to the view that "rights hold, though the heavens may fall," in this article I have maintained that the security arguments of law enforcement do not come close to meeting the threshold for violating privacy rights. The heavens are far from falling. He is the author of, "Employee Monitoring and Computer Technology" (forthcoming in Business Ethics Quarterly), "Intangible Property: Privacy, Power, and Information Control," American Philosophical Quarterly 35 (October 1998) and is the editor of Intellectual Property: Moral, Legal, and International Dilemmas (Lanham, MD: Rowman & Littlefield, 1997), in which he contributes "Introduction to Intellectual Property" and "Toward A Lockean Theory of Intellectual Property."  相似文献   
54.
Motivated by the fact that previous visual memory paradigms have imposed encoding and retrieval constraints, the present article presents two experiments that address how observers allocate eye movements in memory and comparison processes in the absence of constraints. A comparative visual search design (Pomplun, Sichelschmidt, et al., 2001) was utilized in which observers searched for a difference between two images presented side by side. Robust time course effects were obtained, whereby search was characterized by brief fixations and a high proportion of comparative saccades. Then, upon target detection, fixations were extended, more comparative saccades were elicited, and the search focus was narrowed. The saliency and presence of differences did not guide attention, and detection was contingent upon direct fixation of the targets. The results indicate that, when full control is given, observers adopt a strategy that cuts down on memory usage in favor of restricted encoding and active scanning.  相似文献   
55.
For 19 mating-relevant traits, single males (N= 53) and single females (N= 86) rated (a) themselves relative to their same-sex peers, (b) their perceptions of the qualities desired by members of the opposite sex in an ideal partner, and (c) the qualities desired in their own ideal romantic partner. Several themes emerged from the data. First, males’ and females’ judgments of what members of the opposite-sex seek were generally accurate. Second, males and females both feel that they fall short of perceived opposite-sex expectations in a few areas. Third, both males and females desire an ideal partner better than themselves, but this is especially true for females. These findings are discussed in terms of evolutionary social psychological principles.  相似文献   
56.
Many studies of the neural mechanisms of learning have focused on habituation, a simple form of learning in which a response decrements with repeated stimulation. In the siphon-elicited siphon withdrawal reflex (S-SWR) of the marine mollusk Aplysia, the prevailing view is that homosynaptic depression of primary sensory afferents underlies short-term habituation. Here we examined whether this mechanism is also utilized in habituation of the tail-elicited siphon withdrawal reflex (T-SWR), which is triggered by an independent, polysynaptic afferent pathway that converges onto the same siphon motor neurons (MNs). By using semi-intact preparations in which tail and/or siphon input to siphon MNs could be measured, we found that repeated tail stimuli administered in the presence of a reversible conduction block of the nerves downstream of the tail sensory neurons (SNs) completely abolished the induction of habituation. Subsequent retraining revealed no evidence of savings, indicating that the tail SNs and their immediate interneuronal targets are not the locus of plasticity underlying T-SWR habituation. The networks closely associated with the siphon MNs are modulated by cholinergic inhibition. We next examined the effects of network disinhibition on S-SWR and T-SWR habituation using an Ach receptor antagonist d-tubocurarine. We found that the resulting network disinhibition disrupted T-SWR, but not S-SWR, habituation. Indeed, repeated tail stimulation in the presence of d-tubocurarine resulted in an initial enhancement in responding. Lastly, we tested whether habituation of T-SWR generalized to S-SWR and found that it did not. Collectively, these data indicate that (1) unlike S-SWR, habituation of T-SWR does not involve homosynaptic depression of SNs; and (2) the sensitivity of T-SWR habituation to network disinhibition is consistent with an interneuronal plasticity mechanism that is unique to the T-SWR circuit, since it does not alter S-SWR.  相似文献   
57.
The present work investigated mechanisms by which Whites' prejudice toward Blacks can be reduced (Study 1) and explored how creating a common ingroup identity can reduce prejudice by promoting these processes (Study 2). In Study 1, White participants who viewed a videotape depicting examples of racial discrimination and who imagined the victim's feelings showed greater decreases in prejudice toward Blacks than did those in the objective and no instruction conditions. Among the potential mediating affective and cognitive variables examined, reductions in prejudice were mediated primarily by feelings associated with perceived injustice. In Study 2, an intervention designed to increase perceptions of a common group identity before viewing the videotape, reading that a terrorist threat was directed at all Americans versus directed just at White Americans, also reduced prejudice toward Blacks through increases in feelings of injustice.  相似文献   
58.
This study examined the emotional response of 110 adolescents living in the New York metropolitan area one month and five months after the destruction of the World Trade Center (WTC) by terrorists. The purpose of the study was to assess emerging hypotheses in political psychology that suggest that there are differential emotional responses to a national trauma that recede in predictable directions. The results followed predictions and indicate that adolescents experienced a higher level of emotions related to the Crisis and Bereavement dimension than affect associated with Vulnerability and that the emotional response decreased during the four-month follow-up period. There was no effect on emotional response from the biological sex or political orientation of the respondents, which is inconsistent with other studies in the literature. The absence of a political orientation effect is explained in terms of the lack of a domestic ideological difference in response to the terrorist attack.  相似文献   
59.
As people study more facts about a concept, it takes longer to retrieve a particular fact about that concept. This fan effect (Anderson, 1974) has been attributed to competition among associations to a concept. Alternatively, the mental-model theory (Radvansky & Zacks, 1991) suggests that the fan effect disappears when the related concepts are organized into a single mental model. In the present study, attentional focus was manipulated to affect the mental model to be constructed. One group of participants focused on the person dimension of personlocation pairs, whereas the other group focused on the location dimension. The result showed that the fan effect with the focused dimension was greater than the fan effect with the nonfocused dimension, which is contrary to the mental-model theory. The number of associations with a concept is indeed crucial during retrieval, and the importance of the information seems to be accentuated with attentional focus.  相似文献   
60.
The concept of informed consent was one of the most fruitful ideas that deeply changed the relationships between physicians and their patients from paternalism to respect for the personal autonomy of subjects needing professional medical care. The great progress in medicine, also involving the pharmaceutical industry, has created an increasing need to perform different clinical and experimental trials. The evolution of clinical research in the last decades has influenced strongly the design of these studies. One of the most important changes in this field has been the use of placebo groups in double-blind controlled studies. The controversies have involved not only the use of placebo when standard or proven treatment was available, but also some specific problems concerning the procedure of obtaining informed consent in such trials. This paper briefly presents the evolution of informed consent in Poland as well as different ethical and legal problems concerning informed consent and the use of placebo controls in clinical trials. An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research Today,” held in Warsaw, Poland on 12–13 April, 2003.  相似文献   
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