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911.
This study examined whether patients with Korsakoff's disease suffer from increased PI during encoding. The ability of the name of one category, e.g., BIRD, to prime the processing of members of another category, e.g., BODY PARTS, in a lexical decision task was used to assess the amount of PI during encoding. This task required a subject to inhibit the normal associations to BIRD. Young normals (25 years), older normals (48 years), alcoholics (45 years), and alcoholic Korsakoff patients (59 years) performed two lexical decision tasks. In the first experiment, the appearance of the neutral prime XXX 750 msec before the probe signaled that if the probe was a word, there was a 75% chance that it was from a particular category (e.g., BODY PARTS). The prime facilitated reaction time for words from the expected category for all four groups. The prime slowed reaction time for words that were not from the expected category for the young normals but did not influence reaction time for unexpected words for the three older groups. The second experiment was identical to the first except that a category word was used as the prime. The category word used as the prime was unrelated to the category of the words that were likely to follow it. For example, BIRD might be used to signal the likelihood that the word would be from the category, BODY PARTS. Again, young normals were slower to respond to unexpected probe words, but the three older groups were not. Again, the prime facilitated reaction time for expected words for the young normals, older normals, and alcoholics. However, the word prime did not facilitate reaction time for expected words for the alcoholic Korsakoff patients. That the word prime did not facilitate reaction time for the Korsakoff patients was viewed as evidence that they were unable to inhibit its normal associations and were more sensitive to PI from these associations than the other subjects.  相似文献   
912.
The present study explored the factors that contribute to mothers' decisions to seek urgent medical attention for their children when symptoms are not of a traumatic nature. One hundred mothers seeking treatment for their children at a prepaid clinic completed a questionnaire eliciting their expectations regarding the course of their children's problems, seriousness of the problems, perceived responsibility for the symptoms, and extent to which a variety of factors contributed to their decisions to seek treatment. Demographic data and information about each child's symptoms and medical history were also obtained. Four major "reasons for seeking treatment" factors were identified: family history of the presenting complaint, worry regarding the symptoms, situational variables, and the extent of the child's illness behavior. The appropriateness of the visit, delay in seeking treatment, and frequency of mothers' use of the pediatric clinic were predicted by the nature of the presenting symptoms (particularly the presence of fever), the ages of the mother and child, and two of the reasons for seeking treatment factors (i.e., family history and child's illness behavior). The present study suggests that mothers pay more attention to presenting symptoms and to the children's behavior than to psychosocial stressors in deciding to seek urgent care.  相似文献   
913.
Previous studies have examined intra-individual aggregation in the use of cigarettes, alcohol, and coffee by examining the co-occurrent use of any pair of these three substances. A recent literature review failed to find a single investigation that studied use of all three in the same sample. In the present study, co-occurrent use of all three of these substances was examined in crossvalidated subsamples of 226 male and 245 female healthy, community-living, middle-class Americans. A log-linear analysis was used to compare the proportion of smokers, ex-smokers, and nonsmokers categorized as users of more or less amounts of coffee and alcohol. Although most of the intercorrelations were not strong, the results indicate that for both sexes, smokers and ex-smokers were more likely than nonsmokers to drink greater amounts of alcohol and coffee. Furthermore, for smokers, ex-smokers, and nonsmokers, a majority of individuals who reported drinking more alcohol also reported drinking more coffee. Interestingly, the coffee and alcohol consumption levels of ex-smokers resembled those of smokers more than those of nonsmokers. Also, ex-smokers reported drinking more wine and decaffeinated coffee than either smokers or nonsmokers. Finally, the number of cigarettes smoked per day (daily quantity) was positively related to total alcohol and coffee consumption in men, but not in women. Further studies are recommended to examine the role of individual differences in the development, maintenance, and modification of these three appetitive habits and their co-occurrence.  相似文献   
914.
Sleep laboratory studies of patients complaining of insomnia have demonstrated discrepancies between subjective reports and electroencephalograph (EEG)-recorded measures. In our research studies on sleeping aids, 60% of the self-described poor sleepers who reported usual sleep latencies of at least 45 min did not meet the laboratory qualification criterion of a 30-min or longer sleep latency. To learn to predict who would qualify for our studies, we compared 30 laboratory-qualified poor sleepers (QPS) with 30 laboratory-disqualified poor sleepers (DPSs) on subjective report, mood, and all-night sleep laboratory variables. QPSs had significantly lower sleep efficiency and total sleep time in the laboratory, but these differences were due to the longer sleep latencies (50.7 +/- 27.8 min vs. 15.2 +/- 6.1 min) of the QPS group. QPSs and DPSs differed significantly in their morning estimates of their laboratory sleep latencies; as a group, QPSs gave an accurate estimate (51.6 +/- 27.8 min), but DPSs were significantly more likely to exaggerate their sleep latencies. Although we did not identify ways of predicting which poor sleepers would show sleep-onset insomnia in the sleep laboratory, we did find that, in this young, healthy population, there are poor sleepers who give an accurate report of a rather severe sleep-onset insomnia.  相似文献   
915.
The Jenkins Activity Survey (JAS) and the Framingham Type A Scale (FTAS) have been found to have different psychological correlates. The JAS is typically unrelated to anxiety, while the FTAS is consistently correlated with trait anxiety. The present study of 200 male and female college students clarifies further the psychological heterogeneity of these measures. Enhanced motivation to control the environment has been suggested as an underlying psychological component of Type A behavior (Glass, 1977). Dysphoric emotions and the perception of more environmental stresses, on the other hand, are typical of neuroticism or negative affectivity (Watson & Clark, 1984). Although the results indicate that the JAS and FTAS are highly correlated, the JAS is more closely related to control motivation than is the FTAS. Further, compared to the JAS, the FTAS is more closely correlated with dysphoric emotions and perceived daily stresses. Thus, the results indicate that the JAS is closely correlated with core psychological components of the Type A pattern, while the FTAS has a relatively unique association with general emotional distress. Such differences may account for the fact that these measures are related to different disease end points.  相似文献   
916.
Results are presented for the 1st analysis of the relationship between IQ and completed fertility using a large, representative sample of the US population. Correlations are predominantly negative for cohorts born between 1894 and 1964 but are significantly more positive for cohorts whose fertility was concentrated in the baby boom years. Previous studies reporting slightly positive correlations appear to have been biased in their restriction of samples to atypical cohorts. The National Opinion Research Center (NORC), a nonprofit research organization affiliated with the University of Chicago, conducted the General Social Survey (GSS) in the US each year from 1972 to 1982, except for 1979. A combination of block quota and full probability sampling was employed. Hour-long interviews were completed with 12,120 respondents who were English-speaking, noninstitutionalized adults (18 years or older) living within the continental US. Such questions as age, place of birth, income and occupation, were asked in each interview. Other questions about attitudes on various social, political, and moral issues were rotated in different years. The unique opportunity this data set affords is an overview of the relationship between intelligence and fertility for a nationally representative sample of Americans whose major reproductive years fell between 1912 and 1982. Data were consolidated from the 4 surveys in which the vocabulary test was given (1974, 1976, 1978, and 1982). Respondents were divided into 15 birth cohorts of 5-year intervals ranging from before 1894 to 1964. Correlations between vocabulary scores and number of siblings are markedly negative across all 15 cohorts. Vocabulary sibling correlations are more negative in every cohort than vocabulary offspring correlations. Previous reports of a neutral or slightly eugenic relationship appear to be due to the nature of the samples used, in part because the cohorts chosen were atypical, and in part because they did not include nonwhites. Childless respondents averaged slightly higher scores than did those with 1 or more children, indicating that the automatic exclusion of the childless from sibling-IQ studies has not spuriously inflated negative correlations.  相似文献   
917.
918.
Food-deprived Drosophila melanogaster extend their proboscises following sucrose stimulation of the front tarsi (the proboscis extension reflex). Médioni and Vaysse (1975) reported that the inhibition of this response can be conditioned over trials if such proboscis extensions are punished by applying an aversive stimulus to the foreleg tarsi. In this study, Médioni and Vaysse's basic observations of conditioning were replicated, with a different strain of flies and a modified conditioning apparatus.  相似文献   
919.
Three experiments were conducted with adult male Meriones unguiculatus in an attempt to demonstrate that ventral scent marking can act to transfer body heat to the object marked. Experiment 1 showed that surgical removal of the ventral gland pad reduced the amount of heat transferred by 50%, even though intact and glandless animals did not differ in the average frequency of scent marking. Experiment 2 demonstrated that the difference in heat transfer due to the presence or absence of the scent pad was not due to differential pressure applied to the substrate during marking. Experiment 3 showed that the pattern of ventral hair spread that occurs as an animal moves over an object is different between intact and glandless animals but that this difference does not account for the difference in heat transfer. It is suggested that heat transfer to the environment with ventral scent marking may increase thermoregulatory competence and also may function to volatilize sebum used in chemocommunication.  相似文献   
920.
Bornstein’s hypothesis that there is a loss of color discrimination in tropical areas was not supported in earlier research in the Cook Islands. Using a more sensitive color vision test (the Farnsworth-Munsell 100-Hue Test), a loss of color discrimination in the red-purple and blue-green regions of the spectrum was found. The lack of sex differences in this color discrimination loss supports a physiological rather than a genetic explanation of the observed decrement.  相似文献   
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