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851.
A procedure to find out the relationship between systems of entities is described. The crux of the approach depends on projecting the systems to be compared on the same arbitrary hyperspace so that any two systems of entities can be related. The procedure described applies to data presented in square or rectangular non-singular matrices and provides a procedure to determine multiple regression coefficients, multiple correlations, canonical correlations and the relationships between the inner product of the row vectors and of the column vectors of the matrices involved. The operations described apply to raw values, deviation or standard scores, and may help in interdisciplinary research, though the risks involved in the blind application of a mathematical abstract formulation should not be ignored.  相似文献   
852.
We modified the standard procedure for administering finger pressure pain in order to assess the extent to which subjects biased their reports of pain reduction when exposed to compliance-inducing instructions. Experiment 1 used only highly hypnotizable subjects and found that compliance-induced reductions in reported pain were about half as large as the reported reductions produced by hypnotic analgesia suggestions. Experiment 2 used low as well as high hypnotizables and administered hypnotic or nonhypnotic analgesia instructions and compliance instructions to the same subjects on separate pain trials. Reported pain reductions produced by hypnotic and nonhypnotic analgesia suggestions and those produced by compliance instructions were substantially and significantly correlated. Furthermore, hypnotizability correlated with compliance-induced reported pain reductions as highly as it correlated with the reported reductions produced by hypnotic analgesia suggestions. Among high hypnotizables (but not low hypnotizables) compliant responding was predicted by social desirability. The findings of both studies indicate that compliance strongly influences the reports of hypnotic and nonhypnotic analgesia proffered by high hypnotizables. The role of compliance in the pain reductions reported by low hypnotizables is less clear-cut.  相似文献   
853.
Syntactic comprehension disturbances in Japanese aphasics were investigated focusing on the role of category order and thematic role order. The data from Japanese aphasics show that the canonicity of thematic role order determines the ease of interpretation of different sentence types. This finding implies that language-specific factors, rather than language-universal factors, influence the sentence comprehension mechanisms that are retained by aphasic patients.  相似文献   
854.
The purpose of this study was to examine the predictive validity of a teacher nomination procedure for identifying at- risk children. Two hundred and twenty-five children were nominated by their teachers as well- adjusted (n= 75), socially withdrawn (n=76), or socially aggressive (n=74) during the fourth grade. Five years later, 198 of these children (88%) were located and their adjustment evaluated. Significant differences among the nominated children were found on a variety of measures, including academic grades, sociometric status, and social behavior. In addition, differences in school dropout and delinquent offenses were noted. Results are discussed in terms of the validity of teacher nomination procedures and their utility in identifying at- risk youth.  相似文献   
855.
856.
Rate variables and automatized naming in developmental dyslexia   总被引:2,自引:0,他引:2  
The rate variable in rapid automatized naming (RAN) was investigated in 50 adolescent and 40 adult students with developmental dyslexia, in matched normal controls, and in learning-disabled students without reading difficulties. Visual stimuli depicting familiar colors and common objects were presented in isolation at three film speeds and three exposure times. Film speed and exposure time contributed as independent variables to error rate; and dyslexic subjects of both age groups made significantly more naming errors than controls. Dyslexic subjects also responded with longer naming latencies than controls when the same RAN stimuli were presented in a continuous sequential mode as a matrix of rows and columns. Naming latencies in the sequential presentation were highly correlated with naming errors in the film version. The implications of reduced naming rates for nongraphological stimuli in developmental dyslexia are discussed.  相似文献   
857.
The negative repetition effect (NRE) refers to a poorer perception of the target in noise-same-as-target than in noise-alternative-target displays. Using the parenthesis as target and noise that are either identical or different in orientation, we tested predictions derived from a feature-specific inhibition model (Bjork & Murray, 1977) that explains the NRE as arising from inhibitory interactions among channels handling identical inputs. Contrary to our expectation of evidence for orientation-specific inhibition, a positive repetition effect (PRE) was observed. We also found a PRE for the dimension target sets whose stimuli differ only in orientation and an NRE for the feature target sets whose stimuli differ in the number of elements. Further experiments that systematically varied relationships between alternative targets indicate that these basic findings, termed the stimulus attributes effects, do not arise from pattern masking, perceptual strategies, or response bias.  相似文献   
858.
The ability to interpret conversational utterances was assessed in a group of 12 male patients with unilateral right hemisphere brain damage (RHD) and 12 non-brain-damaged, age-matched male control subjects. Subjects listened to short vignettes which described both the affective tone of the relationship between a speaker and an actor, and the actor's performance on a task. Each vignette concluded with the speaker characterizing the actor's performance. In half of the items, the speaker's utterance was literally true; in the other half, the utterance was literally false and invited a nonliteral interpretation. Results showed no appreciable differences in the performance of control subjects and RHD patients when interpreting literally true utterances. In contrast, the two groups differed reliably when interpreting the pragmatic intent of nonliteral utterances: Control subjects used information about both the actor's performance and the speaker-actor relationship, while RHD patients demonstrated difficulty in using the information about the speaker-actor relationship. Results have implications for patients' understanding of essential elements of conversations, such as characters' internal states and their intentions in employing different forms of literal and nonliteral language.  相似文献   
859.
The ontogeny of hemispheric specialization: some old hypotheses revisited   总被引:4,自引:0,他引:4  
This paper re-examines two hypotheses on the ontogeny of hemispheric specialization that long ago fell into disfavor in neuropsychology. It is argued that these hypotheses, equipotentiality and progressive lateralization, may have suffered from misinterpretation that fostered premature acceptance of the developmental invariance view of hemispheric specialization. An alternative view is presented that incorporates both hypotheses within a neurodevelopmental context using anatomical (postmortem) and childhood aphasia data.  相似文献   
860.
In rats, pretraining ip administration of the central benzodiazepine receptor antagonist, flumazenil (5.0 mg/kg), or of the inverse agonist, n-butyl-beta-carboline-3-carboxylate (BCCB) (0.2 or 0.5 mg/kg), facilitated retention of a step-down inhibitory avoidance task; the central agonists, clonazepam and diazepam (0.4 or 1.0 mg/kg), had an opposite effect, and the peripheral agonist, 4'-chlordiazepam (1.25 or 6.25 mg/kg), was without effect. Pre- but not post-training flumazenil (2.0 mg/kg) blocked the effect of BCCB (0.5 mg/kg), clonazepam (1.0 mg/kg), or diazepam (1.0 mg/kg) given also pretraining. The post-training administration of all of these drugs had no effect on retention of the avoidance task. Flumazenil (5.0 mg/kg) and BCCB (0.5 mg/kg), given before training, enhanced retention test performance of habituation to a buzzer but not of habituation to an open field. In the three tasks studied, none of the drugs used had any appreciable effect on training session parameters. These results suggest that there is an endogenous mechanism mediated by benzodiazepine agonists, sensitive to inverse agonists, that normally down-regulates acquisition of certain behaviors; this mechanism becomes activated only when the tasks involve or occur with a certain degree of stress or anxiety (i.e., inhibitory avoidance or habituation to the buzzer) and not in less stressful or anxiogenic tasks (i.e., habituation to an open field).  相似文献   
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