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251.
Categorical coding is the tendency to respond similarly to discriminated stimuli. Past research indicates that pigeons can categorize colors according to at least three spectral regions. Two present experiments assessed the categorical coding of shapes and the existence of a higher order color category (all colors). Pigeons were trained on two independent tasks (matching-to-sample, and oddity-from-sample). One task involved red and a plus sign, the other a circle and green. On test trials one of the two comparison stimuli from one task was replaced by one of the stimuli from the other task. Differential performance based on which of the two stimuli from the other task was introduced suggested categorical coding rules. In Experiment 1 evidence for the categorical coding of sample shapes was found. Categorical color coding was also found; however, it was the comparison stimuli rather than the samples that were categorically coded. Experiment 2 replicated the categorical shape sample effect and ruled out the possibility that the particular colors used were responsible for the categorical coding of comparison stimuli. Overall, the results indicate that pigeons can develop categorical rules involving shapes and colors and that the color categories can be hierarchical.  相似文献   
252.
This paper compares LD and non-LD peers on eight variants of the oddity task. This study is part of a larger programmatic research effort aimed at the development of a screening test to detect preschool children who currently pass existing screening tests but, nonetheless, subsequently experience school failure. The theoretical orientation of this approach is to assess active, ongoing cognitive processing ability. The oddity task, which can be structured to assess such processing ability, was evaluated in the present study as a potential component of this screening test. Consistent with a priori predictions, the data resulted in strong group and developmental differences. Oddity performance increased over age, with the non-LD children performing consistently better than their LD peers at each age. Perceptual and conceptual factors were manipulated across the oddity variations, and both factors contributed to group differences. These results were discussed in relationship to early diagnosis and prognosis for learning disabilities that might result from deficiencies in abstract processing ability.The authors would like to express their thanks to the schools, teachers, and students who participated in this study. This research was supported in part by the Mailman Foundation and FDLRS/MAILMAN, a specialized university center of the Florida Diagnostic Learning Resources System, funded through State General Revenue appropriation to provide multidisciplinary evaluation services in exceptional student education programs.  相似文献   
253.
Quality-of-life measures: hospital interview versus home questionnaire   总被引:2,自引:0,他引:2  
Measures adapted from social survey research were used to assess the quality of life of 33 end-stage renal disease (ESRD) patients in a 2-week test-retest design that varied both location and format of administration (hospital interview vs. home self-administered questionnaire). The measures were found to have substantial consistency over time, location, and format. These results indicate that quality of life is a stable construct and support the usefulness of questionnaire quality-of-life measures for evaluating medical interventions.  相似文献   
254.
Medicaid proposals increasingly focus on cost-saving strategies that restrict clients' control over where and when they may receive services. This study used a field experiment in an urban welfare office to examine the possible effects of two aspects of restrictive policies: the loss of choice of providers and adverse patient mix (i.e., when the majority of a provider's clients are Medicaid beneficiaries). Results indicate that health care presented within the context of not having a choice is derogated and that choice and patient mix combine to influence intentions to seek care. Persons who did not choose the health plan in a simulated choice, who had fewer choices than expected, and who did not accept restricted choice also had negative perceptions.  相似文献   
255.
256.
The three subjects of this article, Charles Citrenbaum, Mark King, and William Cohen, are authors, hypnotherapists, and educators par excellence. In this interview they discuss a variety of topics, including Milton H. Erickson (the “Father of Clinical Hypnosis”), hypnosis, hypnotherapy, and effective clinical practice.  相似文献   
257.
Psychopathology and symptom patterns were studied in 60 former prisoners-of-war (POWs) by administering standardized tests including the Minnesota Multiphasic Personality Inventory (MMPI), an adjustment problem checklist, and a structured clinical interview. Most POWs showed marked psychological impairment, but modal profile analysis identified two prototypic MMPI patterns, which differed in pervasiveness and type of psychopathology. Profile subtypes were defined by unique clusters of clinical symptoms and differed in confinement stress severity. The typology of symptoms argues against a homogeneous conceptualization of stress-induced disorders and suggests the need for definition of the severity and subtype of stress phenomena and individual difference factors in responding to trauma.  相似文献   
258.
Dating experiences, especially the type or stage of dating, have consistently been found to be related to premarital sexual behavior. Findings regarding the age at 1st date and sexual behavior have been less consistent. This paper examined the age at which dating began and the type of dating relationship as correlates of premarital sexual attitudes and behavior among mid-teen adolescents. The analyses were based on a sample of high school students (n=836), most of whom were between the ages of 15 and 18 when the surveys were conducted. Early dating, especially early steady dating, was related to permissive attitudes and to premarital sexual experience among both males and females. The relationship between early dating and intercourse experience was particulary strong among Mormons, a religious group which has institutionalized age 16 as the legitimate age to begin dating.  相似文献   
259.
Three experiments with rats (Rattus norvegicus) were conducted to examine the roles of the male's penile spines and penile cups (flaring of the distal glans) in the induction of luteal activity in the female, and in the removal of copulatory plugs from the vaginal tract. The results of Experiment 1 revealed no role for the cup in luteal induction but did suggest that elements of the ejaculatory reflex apart from cup formation contribute to the elicitation of this neuroendocrine response. The origin of this stimulatory effect was not directly determined, but indirect evidence suggested a role for penile spines. In Experiments 2 and 3, features of the glans penis that might help effect plug removal were investigated, and the experiments demonstrated that penile spines, perhaps in conjunction with penile cups, contribute to the extraction of plugs from the vagina.  相似文献   
260.
Sex difference trends in completed suicide   总被引:1,自引:0,他引:1  
The recent suicide literature increasingly has contained statements suggesting that the differences in completed suicide between the sexes are lessening. A compilation of official suicide data for 1933-1980 verifies such a trend from the 1950s through 1971. However, increased differences (as measured by the ratio of male to female rates) were consistently observed from 1971 to 1980. These trends were found for data for the nation, for whites and nonwhites, for numbers of suicides, for crude rates, and for age-adjusted rates. Decreased sex differences were obtained for those 35-44, 45-54, 55-64, and for 65+ years of age, but increased sex differences were observed for those aged 15-24 and 25-34. Possible explanations for these findings are presented.  相似文献   
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