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921.
Videocassettes have become the dominant medium for pornography. One previous content analysis examined the prevalence of violence in such videos. The Attorney General's Commission on Pornography (1986) has asserted that nonviolent pornography depicting degradation produces harm similar to that from violent pornography. Content analysis of a 10% random sample (n = 50) of the videos displayed in the "adult" section of a video store showed that 13.6% of the scenes in the videos contained violent acts and 18.2% contained degrading acts.  相似文献   
922.
This study examined three factors affecting college students' attributions of blame for an AIDS patient's disease: sexual orientation of the patient, mode of HIV transmission, and the sex of the subject. 148 subjects read one of six vignettes describing an hypothetical AIDS patient who was described as either an heterosexual or an homosexual man who contracted HIV through one of three avenues: blood transfusion, sexual contact, or IV drug use. The homosexual AIDS patient was considered more to blame for his illness than the heterosexual AIDS patient, but only when mode of transmission was sexual contact. In addition, mode of HIV transmission was a significant factor in attributions of responsibility, as the patient who contracted HIV through a blood transfusion was rated as less responsible than the patient who contracted HIV through sexual behavior or IV drug use. Women consistently rated the AIDS patient as less responsible than did men.  相似文献   
923.
Some clarifications of the CANDECOMP algorithm applied to INDSCAL   总被引:2,自引:0,他引:2  
Carroll and Chang have claimed that CANDECOMP applied to symmetric matrices yields equivalent coordinate matrices, as needed for INDSCAL. Although this claim has appeared to be valid for all practical purposes, it has gone without a rigorous mathematical footing. The purpose of the present paper is to clarify CANDECOMP in this respect. It is shown that equivalent coordinate matrices are not granted at global minima when the symmetric matrices are not Gramian, or when these matrices are Gramian but the solution not globally optimal.Part of this research has been supported by The Netherlands Organization for Scientific Research (NWO), PSYCHON-grant (560-267-011).  相似文献   
924.
The effect of information integration on the recall of ambiguous prose passages was investigated. In Experiment 1, subjects read ambiguous passages that were difficult to comprehend without titles. In judging the relative positions in the passages of pairs of test sentences, subjects performed better when they read passages headed by a suitable title than when they read untitled passages or received a title at the time of testing. In Experiment 2, subjects provided with a title at encoding also better discriminated complete old sentences from foils composed of fragments of two different old sentences than did subjects provided with no titles or with titles at the time of testing. These two tests index the degree of inter- and intrasentence information integration, respectively. Two findings indicated that integration affected free recall of an ambiguous passage. First, when the degree of integration of the passage's propositions was controlled, free recall of the passage was no different for subjects who did or did not know the passage's title at encoding. Second, inducing subjects to comprehend the passage's sentences individually, without relating them to one another, reduced free recall of the passage.  相似文献   
925.
Treiman (1983) and others have argued that spoken syllables are best characterized not as linear strings of phonemes, but as hierarchically organized units consisting of an onset (initial consonant or consonant cluster) and a rime (the vowel and any following consonants) and that the rime is further divided into a peak or nucleus (the vowel) and a coda (the final consonants). It has also been argued that the sonority (or vowel-likeness) of the consonant closest to the peak, which is a function of its phonetic class, may have an effect on the strength of boundaries determined by the hierarchical division of the syllable (e.g., Treiman, 1984). We examined the evidence for syllable-internal structure and for sonority in two experiments that employed visually presented stimuli and lexical decision, naming, and reading tasks. Our results provide support for the breakdown of the rime into a peak and a coda and for an effect of the sonority of the postvocalic consonant on that break. This pattern occurred only in our lexical decision tasks, so the effect is assumed to be postlexical. We did not find an effect of the onset-rime boundary, perhaps because of an unanticipated effect of word frequency. Our results are discussed in terms of phonological coding in short-term memory.  相似文献   
926.
There appear to be beneficial effects of stimulant medication on daily classroom measures of cognitive functioning for Attention Deficit Disorder (ADD) children, but the specificity and origin of such effects is unclear. Consistent with previous results, 0.3 mg/kg methylphenidate improved ADD children's performance on a classroom reading comprehension measure. Using the Posner letting-matching task and four additional measures of phonological processing, we attempted to isolate the effects of methylphenidate to parameter estimates of (a) selective attention, (b) the basic cognitive process of retrieving name codes from permanent memory, and (c) a constant term that represented nonspecific aspects of information processing. Responses to the letter-matching stimuli were faster and more accurate with medication compared to placebo. The improvement in performance was isolated to the parameter estimate that reflected nonspecific aspects of information processing. A lack of medication effect on the other measures of phonological processing supported the Posner task findings in indicating that methylphenidate appears to exert beneficial effects on academic processing through general rather than specific aspects of information processing.  相似文献   
927.
The developmental course of rhythmic motor behavior was followed longitudinally for three groups of preambulatory children — normally developing, Down syndrome, and those with profound motor impairment. The groups differed in chronological age but were comparable with respect to motor age. The motor impaired subjects displayed significantly less rhythmic motor behavior than the nondisabled and Down syndrome groups. In comparing particular subtypes of rhythmic motor behavior, differences were found in both the average number of bouts and duration of subtypes among the groups. Longitudinal analyses of the data over the entire observation period revealed that the rhythmic motor behavior of the children with Down syndrome was more similar to that exhibited by the nondisabled children than was the rhythmic motor behavior of the children with motor impairment. However, there was considerable variability among the groups in several particular subtypes.This research was supported by grants from the National Institute of Child Health and Human Development (HD 17650 and HD 07226).The authors acknowledge the assistance of Robert E. Arendt, Grant Youngquist, Michael Hohn, and Charles Lowitzer in obtaining the observational data and thank the families of the subjects for their enthusiasm and dedication to the project.This study was presented at the 23rd Annual Gatlinburg Conference on Research and Theory in Mental Retardation and Developmental Disabilities, April 21, 1990.  相似文献   
928.
We investigated the effects of background anger, provocation, and methylphenidate on emotional, physiological, and behavioral responding in children with attentiondeficit hyperactivity disorder (ADHD) with and without concurrent aggression. Our study revealed that ADHD boys showed more emotional and physiological distress when exposed to an interaction in which an administrator chastised each boy's favorite counselor, compared to a friendly interaction between the two adults. The background anger manipulation did not affect the aggressive behavior of the boys against an opponent in an aggressive game. High-aggressive (HA) ADHD boys were more likely to respond to provocation with aggression than low-aggressive (LA) ADHD boys, but only LA boys showed increased physiological reactivity with increasing provocation. Methylphenidate resulted in increased heart rates under all conditions and did not interact with any of the other findings.This project was conducted while the first author had the support of National Institute of Alcohol Abuse and Alcoholism grant AA 06267.The authors wish to thank the staff members of the 1987 Summer Day Treatment Program who assisted in conducting this project. The authors also express their appreciation to Karen Guthrie for coordinating the medication assessment and to Hart Blanton for computer programming.  相似文献   
929.
Word repetitions in sentence recognition   总被引:1,自引:0,他引:1  
When some items on a list are strengthened by extra study time or repetitions, recognition of other, unrelated, list items is not harmed (Ratcliff, Clark, & Shiffrin, 1990). Shiffrin, Ratcliff, and Clark (1990) accounted for this list-strength finding with a model assuming that different items are stored separately in memory, but that repetitions are accumulated together into a single stronger memory trace. Repeating words in the context of different sentences might cause separate storage of the repetitions of a given word, because either word or sentence traces are stored separately. Separate storage would, in effect, convert a list-strength manipulation into a list-length manipulation and thereby induce a positive list-strength effect. In Experiment 1, this result was produced for single-word recognition and for two types of sentence recognition. In Experiment 2, both words and sentences were repeated together, which should have caused repetitions to be stored in a single, stronger, trace. As expected, the list-strength effect was eliminated. A sentence trace model was fit to the data, supporting the account of Shiffrin et al. (1990) and supporting an account of word and sentence recognition in which activation is summed for representations of all list items. The results from the two studies are inconsistent with most current models of memory (as shown by the theoretical analyses of Shiffrin et al., 1990) and pose an additional challenge for theory.  相似文献   
930.
Automatic processes in lexical access and spreading activation.   总被引:1,自引:0,他引:1  
The semantic priming effect can be reduced or eliminated depending on how the prime word is processed. The experiments reported here investigate this prime task effect. Two experiments used identity and semantic priming tasks to determine whether the prime word is encoded at a lexical level under letter-search conditions. When the prime task was naming, both identity and semantic priming occurred; however, when a letter-search task was performed on the prime word, only identity priming occurred, thus supporting the argument that the search task affects activation of semantic associates rather than lexical access of the prime word. Another experiment demonstrated that this identity priming was the result of lexical processes rather than of letter-by-letter priming. A cross-modal priming technique demonstrated that the letter-search prime task does not actively suppress activation of semantic associates. The implications of these results for automaticity and for proposed mechanisms of priming are discussed.  相似文献   
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