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101.
A review of research on prenatal depression effects on the fetus and newborn suggests that they experience prenatal, perinatal and postnatal complications. Fetal activity is elevated, prenatal growth is delayed, and prematurity and low birthweight occur more often. Newborns of depressed mothers then show a biochemical/physiological profile that mimics their mothers' prenatal biochemical/physiological profile including elevated cortisol, lower levels of dopamine and serotonin, greater relative right frontal EEG activation and lower vagal tone. Elevated prenatal maternal cortisol is the strongest predictor of these neonatal outcomes. Moderate pressure massage can alleviate these effects including reducing prematurity.  相似文献   
102.
Novice, intermediate, and expert chess players of various ages, playing with two chess pieces on a quarter-section of a chessboard, performed a simple task to detect that the king is in check or is threatened with being in check. Age slowed response for both tasks. An interaction of task and skill revealed differences in diminishing response time between check and threat tasks as skill increased; experts were equally fast on both tasks. Measures of speed and working memory were negatively related to age but unrelated to skill. Skill did not mitigate age-related effects on speed of detection. These results suggest that knowledge-activation processes necessary to assess basic chess relationships slow with age, even in experts.  相似文献   
103.
To examine Latina college students' sexual health beliefs about human papillomavirus (HPV), 16 self-identified Latina college students from a large Midwestern university participated in three focus groups. The authors found that participants' knowledge of HPV and cervical cancer was extremely low. Women did not obtain Pap screenings consistently, nor did they use condoms in a consistent manner. They perceived that cultural norms that support silence about sexual topics hinder their knowledge acquisition about sexual issues. Participants also recognized that their insufficient knowledge could jeopardize their health and expressed a willingness to actively stop this intergenerational cycle of silence within their families. Findings highlight the importance of incorporating cultural considerations when designing research and educational programs with Latina college students.  相似文献   
104.
Curiosity as a feeling of deprivation (CFD) reflects feelings of uncertainty and tension that motivate information-seeking and problem-solving behavior. Twenty-seven CFD items were administered to 321 participants (248 women, 73 men) along with other measures of curiosity and other personality traits such as anxiety, anger, and depression. Factor analyses of the CFD items identified 3 factors from which 5-item subscales were developed: (a) a need to feel competent, (b) intolerance experienced when information is inaccessible or inadequate, and (c) a sense of urgency to solve problems. Moderately high correlations of the CFD scales with other measures of curiosity provided evidence of convergent validity, whereas divergent validity was demonstrated by minimal correlations of the CFD scales with the other personality traits.  相似文献   
105.
Herrnstein's hyperbola describes the relation between response rate and reinforcer rate on variable-interval (VI) schedules. According to Herrnstein's (1970) interpretation, the parameter r(e) represents the reinforcer rate extraneous to the alternative to which the equation is fitted (the target alternative). The hyperbola is based on an assumption that extraneous reinforcer rate remains constant with changes in reinforcer rate on the target alternative (the constant-r(e) assumption) and that matching with no bias and perfect sensitivity occurs between response and reinforcer ratios. In the present experiment, 12 rats pressed levers for food on a series of 10 VI schedules arranged on the target alternative. Across conditions, six VI values and extinction were arranged on a second alternative. Reinforcer rate on the second alternative, r2, negatively covaried with reinforcer rate on the target alternative for five of the six VI values on the second alternative, and significant degrees of bias and undermatching occurred in response ratios. Given covariation of reinforcer rate on the second and target alternatives, the constant-r(e) assumption can be maintained only by assuming that reinforcer rate from unmeasured background sources, rb, covaries with reinforcer rate on the second alternative such that their sum, r(e), remains constant. In a single-schedule arrangement, however, r(e) equals rb and thus rb is assumed to remain constant, forcing a conceptual inconsistency between single- and concurrent-schedule arrangements. Furthermore, although an alternative formulation of the hyperbola can account for variations in bias and sensitivity, the modified equation also is based on the constant-r(e) assumption and therefore suffers from the same logical problem as the hyperbola when reinforcer rate on the second alternative covaries with reinforcer rate on the target alternative.  相似文献   
106.
An approach based on Skinner's (1957) theory of verbal behavior has been developed to understand and teach elementary communication skills to children with autism and developmental disabilities (Sundberg & Partington, 1998). However, few studies have directly examined the characteristics of emerging language in children with developmental disabilities. The purpose of this study was to develop and evaluate an assessment for identifying the elementary functions of vocal speech in children. Participants were 4 children with developmental disabilities, aged 6 years to 12 years, who exhibited at least one distinguishable vocal response (word or phrase) frequently in the natural environment. The assessment focused on three verbal operants delineated by Skinner (mand, tact, and intraverbal). One or more functions were identified for at least one vocal response of each child. Results suggested that this assessment would be useful for (a) evaluating Skinner's theory, (b) guiding decisions about language training for individual children, and (c) studying the nature of expressive language development in children with developmental disabilities.  相似文献   
107.
Acoustic communication in black-capped chickadees (Poecile atricapillus) has been studied intensively, the "chick-a-dee" call being among the most well described. This call consists of 4 note types; chickadees perceive these notes as open-ended categories and do so in a continuous manner, with As more similar to Bs and Bs more similar to Cs. Acoustic features contributing to the note-type differentiation are unknown. Recent analyses suggested that certain acoustic features may play a role in note-type classification. Here, the authors tested black-capped chickadees in an operant-conditioning paradigm to determine which features were controlling note-type perception. The results suggest that the note pitch and the frequency modulation in the initial portion of the note control the perception of note types.  相似文献   
108.
We have shown previously that the antiepileptic phenytoin impairs transfer in an instrumental learning task (Banks et al., 1999). The present study examined the effects of contextual alterations on appetitive-to-aversive transfer performance of rats treated with either phenytoin or tang. Adult rats were tested in tone-signaled appetitive and aversive instrumental tasks, where the animal bar-pressed to obtain a food reward (sugar pellet) or to avoid shock. Rats were trained on the appetitive task for 31 days. Beginning on the twenty-first day, rats were gavaged with either phenytoin or tang twice daily. Animals were then transferred to aversive training, with the phenytoin or tang treatment continuing throughout the 25 testing days. For some animals, contextual changes were introduced as they shifted from appetitive to aversive training, while for other animals these changes were not made. Phenytoin-treated rats that were presented with changes in context as they transferred from the appetitive to the aversive task learned the avoidance response to levels substantially higher than drug-treated rats not presented with the contextual changes. These results indicate that phenytoin impairs avoidance learning following transfer from the appetitive task, and that this impairment can be eliminated by introducing changes in context at the point of transfer. In the tang-treated control subjects, on the other hand, there was no improvement in transfer learning performance associated with the changes in contextual cues. This pattern of results suggests that contextual encoding processes in rats being trained in an instrumental appetitive-to-aversive paradigm are dramatically affected by phenytoin.  相似文献   
109.
Forensic mental health assessment (FMHA) is a form of evaluation performed by a mental health professional to provide relevant clinical and scientific data to a legal decision maker or the litigants involved in civil or criminal proceedings. Such FMHA evaluations can be further specialized when the clinical and scientific data are primarily neuropsychological. This paper provides an adaptation of 29 recently derived principles of FMHA (Heilbrun, 2001) that have been described in two forms: general guidelines for application in FMHA, and guidelines for application to neuropsychological assessment in forensic contexts. Each principle is described, and the general guideline is compared with the highly specialized neuropsychological guideline. In this way, the applicability of such FMHA principles to forensic neuropsychological assessment is described.  相似文献   
110.
The degree to which perceivers automatically attend to and encode social category information was investigated. Event-related brain potentials were used to assess attentional and working-memory processes on-line as participants were presented with pictures of Black and White males and females. The authors found that attention was preferentially directed to Black targets very early in processing (by about 100 ms after stimulus onset) in both experiments. Attention to gender also emerged early but occurred about 50 ms later than attention to race. Later working-memory processes were sensitive to more complex relations between the group memberships of a target individual and the surrounding social context. These working-memory processes were sensitive to both the explicit categorization task participants were performing as well as more implicit, task-irrelevant categorization dimensions. Results are consistent with models suggesting that information about certain category dimensions is encoded relatively automatically.  相似文献   
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