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11.
Working in the fragment of Martin-Löfs extensional type theory [12] which has products (but not sums) of dependent types, we consider two additional assumptions: firstly, that there are (strong) equality types; and secondly, that there is a type which is universal in the sense that terms of that type name all types, up to isomorphism. For such a type theory, we give a version of Russell's paradox showing that each type possesses a closed term and (hence) that all terms of each type are provably equal. We consider the kind of category theoretic structure which corresponds to this kind of type theory and obtain a categorical version of the paradox. A special case of this result is the degeneracy of a locally cartesian closed category with a morphism which is generic in the sense that every other morphism in the category can be obtained from it via pullback.The financial support of the Royal Society in London is gratefully acknowledged.  相似文献   
12.
Four experiments were conducted to test earlier claims about the relationship between the negative afterimage and the McCollough effect. The first claim (Hansel & Mahmud, 1978) is that long-lasting afterimages occur when induced by the same alternating-stimulus procedure as that used to induce the McCollough effect. The second claim (Murch & Hirsch, 1972) is that afterimages can themselves induce McCollough effects if they are induced and paired sequentially with grating patterns. In testing these claims, a reliable computer-controlled color-cancellation technique developed earlier was used to measure the apparent color of both afterimages and McCollough effects objectively. No support was found for the first claim following alternative presentation of two homogeneously colored regions for total periods of 5 min (Experiment 1) and 20 min (Experiment 2). The second claim was fully supported: After an induction period of 7.3 min, a McCollough effect occurred for a red-vertical pairing but not for a green-horizontal pairing (Experiment 3); but after an induction period of 20 min, McCollough effects occurred strongly for both pairings (Experiment 4). The theoretical implications of these outcomes are considered in the context of recent theories of color and pattern processing in the visual system.  相似文献   
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14.
Recent reports have indicated similarities between patients with persistent chest pain of nonorganic origin and patients with panic disorder. In order to explore this association further, we administered a structured interview and three self-report measures (State-Trait Inventory, Beck Depression Inventory, and SCL90-R) to three subject groups: (1) a sample with persistent chest pain (CP; n=14) who had been screened and found to have normal coronary arteries, (2) a sample of patients with panic disorder (PD; n=14), and (3) a sample of matched normals (n=14). CP patients were considered to be free of coronary artery disease (CAD) following normal cardiac catheterization and/or normal thallium stress tests and were not diagnosed initially with panic disorder. PD patients were diagnosed with a standardized psychiatric interview and were free of organic causes of panic. Using an exploratory data analytic approach, the results indicated that both CP and PD samples reported increased levels of state and trait anxiety (p <.0001), depression (p <.01), and somatization (p <.0001) compared with normals. CP patients differed from PD patients in their less frequent use of anxiolytic medication (p <.01) and lower levels of reported panic anxiety and phobic avoidance (p <.0001). These data suggest that persistent chest pain in the absence of CAD shares some features with panic disorder, yet differs from panic in key ways as well. The results are discussed in light of the role of anxiety in contributing to symptom labeling.This research was supported by Grant 86G-491 from the American Heart Association, Texas Affiliate, to J.G.B. H.T. is the recipient of USPHS Research Career Development Award K04-HL-0122246.  相似文献   
15.
Eleven subjects were asked to silently read slides of the letters “P” and “T,” and to view meaningless control slides similarly as they were presented visually. One-eighth-second electromyographic excerpts were sampled from the baseline and response periods. The data were then transformed into the frequency domain for inferential analyses. The mean power spectral frequencies for the response period were significantly lower than those for the base-line in the overall analysis. There were, however, no significant changes from baseline as a function of kind of stimulus (T, P, or Control) or muscle activated (lips or tongue). It was concluded that there was a generalized responding, not unique to the processing of the specific stimuli studied. Frequency analysis of EMG measures of covert behavior holds some promise of yielding unique information not available through traditional analysis procedures, but more sensitive methods than those used here would be required to demonstrate this.  相似文献   
16.
We conducted an investigation to evaluate the effects of a training strategy for teaching autistic students generalized responses to three forms of wh— questions (what, how, and why). Students were taught, using modeling and reinforcement procedures, to answer questions with magazine pictures as the referents. Each question form was divided into two or more subcomponents reflective of common social usage and was taught within the context of a modified multiple probe design across subcomponents. Following acquisition of each subcomponent, generalization to natural context and storybook questions was assessed; additional probes were conducted to assess responding over time and whether acquisition of responses to questions promoted question-asking skills. Results showed that the picture training procedure was effective in teaching a generalized response to questions for which the relevant cue was visible, whereas specific generalization programming was required for situations in which the relevant cue was not visible. All acquired responses were durable over time.  相似文献   
17.
Counting On Blood Donors: Increasing the Impact of Reminder Calls   总被引:1,自引:0,他引:1  
Two experiments were conducted to see if blood drive attendance could be increased by altering the content of reminder calls. In Experiment 1 college students received either a standard reminder (the place, time, and necessity of eating beforehand) or a commitment-enhancing reminder in which they agreed to be "counted on". Those in the latter condition were significantly more likely (p <.007) to attend a blood drive. Experiment 2 demonstrated that an alternate wording for the commitment-enhancing message was possible; that a verbal response was necessary to ensure the commitment; and that a message enhancing altruism was not as effective. The studies suggest that asking for an additional commitment during a reminder call can appreciably increase blood drive participation rates.  相似文献   
18.
Reviews     
H enderson , J oseph L. Cultural Attitudes in Psychological Perspective
C arotenuto , A ldo . The Vertical Labyrinth: Individuation in Jungian Psychology
K ugelmann , R obert . The Windows of Soul: Psychological Physiology of the Human Eye and Primary Glaucoma
D ryden , W indy (ed.). Individual Therapy in Britain
W elch , J ohn . Spiritual Pilgrims: Carl Jung and Teresa of Avila
T omlin , E. W. F. Psyche, Culture and the New Science: The Role of PN  相似文献   
19.
Right-handed adults were asked to identify by name bilaterally presented words and pronounceable nonwords. For words in the normal horizontal format, word length (number of letters) affected left visual hemifield (LVF) but not right visual hemifield (RVF) performance in Experiments 1, 2, 3, 5, and 6. This finding was made for words of high and low frequency (Experiment 6) and imageability (Experiment 5). It also held across markedly different levels of overall performance (Experiments 1 and 2), and across different relative positionings of short and long words in the LVF and RVF (Experiment 3). Experiment 4 demonstrated that the variable affecting LVF performance is the number of letters in a word, not its phonological length. For pronounceable nonwords (Experiment 7) and words in unusual formats (Experiment 8), however, length affected both LVF and RVF performance. The characteristics identified for RVF performance in these experiments also hold for the normal reading system. In this (normal) system the absence of length effects for horizontally formatted words is generally taken to reflect the processes involved in lexical access. Length effects in the normal reading system are thought to arise when lexical access for unusually formatted words and for the pronunciation of nonwords requires the short-term storage of information at a graphemic level of analysis. The characteristics of LVF performance indicate that horizontally formatted words presented to the right cerebral hemisphere can only achieve lexical access by a method that requires the short-term storage of graphemic information. This qualitative difference in methods of lexical access applies regardless of whether the right hemisphere is seen as accessing words in the left hemisphere's lexicon or words in a lexicon of its own.  相似文献   
20.
Reviews     
F ordham , M ichael . Explorations into the Self
R edpearn , J oseph . My Self, My Many Selves
H obson , R obert F. Forms of Feeling: the Heart of Psychotherapy
C asement , P atricia . On Learning from the Patient
S hepherd , M ichael . Sherlock Holmes and the Case of Dr Freud
A bend , S. M., P order , M. S., W illick , M. S. Borderline Patients: Psychoanalytic Perspectives
V an H erik , J udith . Freud on Femininity and Faith  相似文献   
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