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271.
In this article, we address the effects on haptic recognition of common objects when manual exploration is constrained by using two kinds of rigid links--sheaths (Experiment 1A) and probes (Experiments 1B and 2). The collective effects of five different constraints are considered, including three from previous research (i.e., reducing the number of end effectors, wearing a compliant finger cover, and splinting the fingers; Klatzky, Loomis, Lederman, Wake, & Fujita, 1993) and from two current constraints (i.e., wearing a rigid finger sheath and using a rigid probe). The resulting impairments are interpreted in terms of the loss of somatosensory information from cutaneous and/or kinesthetic inputs. In addition, we relate the results to the design of haptic interfaces for teleoperation and virtual environments, which share some of the same reduction of sensory cues that we have produced experimentally.  相似文献   
272.
The number, amplitude, duration, and bout structure of isolation-induced ultrasonic vocalization (USV) of infant rats (Rattus norvegicus) were measured on postnatal Day 10. Measurements were made before and after a brief, 1-min, active interaction with their mother or before and after a "pick-up" control procedure. Consistent with prior studies, the number of USVs emitted was significantly increased in the period following the maternal reunion but not after the control procedure. The average amplitude of USVs was also greater following maternal reunion. Finally, analyses characterizing the bout structure of USV production indicated that the average bout size (i.e. number of USVs/bout) was increased severalfold following the reunion with the mother, accounting for the greater rate of USV production during the second isolation period.  相似文献   
273.
Young and older adults' eye fixations were monitored as they read sentences with temporary ambiguities such as "The experienced soldiers warned about the dangers conducted the midnight raid." Their fixation patterns were similar except that older adults made many regressions. In a 2nd experiment, high- and low-span older adults were compared with high- and low-span young adults. Pint-pass fixations were similar, except low-span readers made many regressions and their total fixation times were longer. High-span readers also used the focus operator "only" (e.g., "Only experienced soldiers warned about the dangers.") to immediately resolve the temporary ambiguities. No age group differences were observed. These results are discussed with reference to theories of the role of working memory in sentence processing.  相似文献   
274.
Many gay, lesbian, and bisexual adults report a period of childhood sexual questioning--an uneasy questioning of their heterosexuality brought on by same-sex attractions and motivating same-sex sexual exploration. This article evaluates hypotheses about the correlates, causes, and consequences of childhood sexual questioning. Participants were 182 children in the 4th through 8th grades. Compared with children more confident in their heterosexuality, sexual-questioning children reported more impaired self-concepts, fewer same-sex-typed attributes (but not more cross-sex-typed attributes), a greater sense of feeling different from same-sex others, and lesser satisfaction with their gender assignment. Short-term longitudinal analyses indicated that sexual questioning is more likely a determinant than a consequence of these correlated variables. However, influences of sexual questioning on these outcomes were small.  相似文献   
275.
This study examined the stability and continuity of early-identified behavior problems and the factors associated with this stability. Children and their mothers (N=125) were seen when the children were 2 and 4 years of age. Maternal reports of child externalizing behavior and laboratory observations of child noncompliance were stable from age 2 to age 4. Early externalizing behaviors decreased over time; however, child noncompliance in the laboratory did not. Although few associations were found between maternal positive behavior and child behavior problems, maternal controlling behavior was related to increases in child behavior problems, particularly at high levels of both prior noncompliance and prior maternal control. Child noncompliance was predictive of increases in maternal controlling behavior over time.  相似文献   
276.
Findings are presented of a study of families created through surrogacy arrangements. Forty-two surrogacy families were compared with 51 egg-donation families and 80 natural-conception families on standardized interview and questionnaire measures of the psychological well-being of the parents, the quality of parent-child relationships, and infant temperament. The differences that were identified between the surrogacy families and the other family types indicated greater psychological well-being and adaptation to parenthood by mothers and fathers of children born through surrogacy arrangements than by the natural-conception parents.  相似文献   
277.
This article deals with critical psychic transformation in a schizoid personality disorder that evolves in an object relations psychoanalysis in which "developmental mourning" plays a central role. Within a mourning process that allows for the grieving of loss related to arrested separation-individuation development, the analysand confronts the existential grief of regret that had always unconsciously haunted her. The unconscious guilt related to the existential grief of regret had caused much dissociation of self-experience and affect states. The analysand acknowledges her own part in the destruction of primal and current relationships after the traumatic impact of her early life is understood. This allows her to repair current relationships, both within her internal and external worlds so that she can open to capacities for love and creativity. The analysand's courage to consciously grapple with her regret (loss and guilt combined) allows her to relinquish self-sabotaging character defenses such as contempt and emotional withdrawl. Consequently, a second marriage is salvaged and enriched, and the analysand's relationship with her two children is dramatically improved.  相似文献   
278.
Faculty members at Canadian business schools were surveyed regarding their ethical perceptions of behaviours related to undergraduate instruction. Fifty-five behavioural statements were listed and respondents were asked to rate the extent to which they felt each behaviour was ethical or unethical. The only item that respondents endorsed as unequivocally unethical (90% indicated it was definitely unethical) was Becoming sexually involved with an undergraduate in one of your classes. We also compared the results of our sample to those of an American sample. Overall, an interesting pattern of differences emerged between the responses obtained in Canada and the U.S. In general, the direction of the significant differences was such that Canadian professors viewed the behaviours in question as less ethical than did their American counterparts.  相似文献   
279.
This study describes the effects of different weekly work intensity levels on adolescent functioning in a sample of 3,083 high school students in rural South Texas, where economically disadvantaged and Hispanic youth are heavily represented. Anonymous surveys were conducted in 10th- and 12th-grade students' classrooms in 1995. The following effects were associated with long hours of weekly employment during the school year: (1) decreased performance/engagement in school and satisfaction with amount of leisure time, and (2) increased health risk behaviors and psychological stress. The effects of school-year work on academic factors and health behaviors differed by grade, but not by race/ethnicity, parent education, or race/ethnicity and parent education considered together. It was concluded that parents and professionals should continue to monitor the number of weekly hours that students work during the school year.  相似文献   
280.
The authors bring psychological research to bear on an examination of the policy of affirmative action. They argue that data from many studies reveal that affirmative action as a policy has more benefits than costs. Although the majority of pro-affirmative action arguments in the social sciences stress diversity, the authors' argument focuses on issues of merit. The merit-based argument, grounded in empirical studies, concludes that the policy of affirmative action conforms to the American ideal of fairness and is a necessary policy.  相似文献   
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