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861.
The influence of an isolated word’s meaning on lexical decision reaction time (RT) was demonstrated through four experiments. Subjects in two experiments made lexical decision judgments, those in a third experiment pronounced the words used in the lexical decision task, and those in a fourth experiment quickly pronounced their first associative response to the words. Differences in lexical access time for the words were measured with the pronunciation task, and differences in meaning were assessed with the association task. Multiple regression analyses of lexical decision RT were conducted using associative RT, pronunciation RT, and other target word properties (printed frequency, length, instance dominance, and number of dictionary meanings) as predictor variables. These analyses revealed a relationship between lexical decision RT and associative RT after the effects of other variables had been partialed out. In addition, word frequency continued to have a significant relationship to lexical decision RT beyond that shared with pronunciation RT and the other variables. The results of these experiments indicate that at least some of the effect of word meaning and word frequency in lexical decision is attributable to a decision stage following lexical access.  相似文献   
862.
It was proposed that parents of hyperactive children would observe more problems at home in some but not all home contexts. To test this hypothesis, parents of teacher-identified hyperactive and nonhyperactive children were asked to complete a context-specific behavioral rating scale (Werry, 1968). Hyperactive children were rated by their parents as changing activities, talking, interrupting, and exhibiting dependency more than nonhyperactive children. Furthermore, those differences between hyperactive and control children were observed primarily in the play and homework contexts.This research was supported by a National Institute of Mental Health Grant MH(32282).  相似文献   
863.
864.
Two experiments are described in which subjects rated as high or low in achievement motivation were exposed to uncontrollable outcomes on a cognitive task. Effects on subsequent performance on a different cognitive task were shown to depend on level of achievement motivation, on whether the uncontrollable outcomes were predictable or unpredictable, and on whether the uncontrollable outcomes were positive or negative. These findings have important theoretical implications which are discussed.  相似文献   
865.
The empirical research pertaining to the effectiveness of telephone counseling and referral systems personnel was critically reviewed. The assessment was organized according to several evaluation strategies that researchers have utilized to evaluate effectiveness. These strategies included, for example, client self-reports, client "shows" versus "no-shows" following referral, data pertaining to suicide rates, counselor ratings of personal effectiveness, and phone workers' ability to offer empathy to clients. It was concluded that discussions of effectiveness should be constrained by a careful consideration of the specific index of efficacy chosen by investigators as well as methodological issues associated with current research in this area. There is reason to believe that the availability of telephone crisis services may be related to reduced suicide rates among young white females. Also, there is a significant need to empirically associate counseling technique and indices of effectiveness with substantive measures of client outcome in future research. Additional topics reviewed include the probable differential effectiveness of lay workers with various presenting problems of clients, and the role that training and maturity seem to play in successful interventions. Guidelines for the use of evaluation techniques which coincide with service goals are also offered.  相似文献   
866.
Using male hooded Lister rats the effects of GABAergic and serotonergic treatments alone and with chlordiazepoxide (CDP) were compared with the behavioral effects of CDP in a conditioned conflict procedure with three components; Reward, Time Out, and Conflict. CDP (2.5, 5.0, and 10.0 mg/kg ip) dose- relatedly increased punished and time out responding, but increased rewarded responding in an inversely dose-related manner. Punished responding was enhanced by chronic treatment to a rate which remained stable between 9 and 19 injections. The GABA transaminase inhibitor ethanolamine-O-sulfate (EOS), given chronically in drinking water (5.0 mg/ml), increased punished responding linearly to a high stable level after 2-3 weeks. Rewarded and time out responding were less substantially increased. CDP given with EOS dose- relatedly increased time out and punished responding substantially above the rates found with either treatment alone. The GABA antagonist picrotoxin blocked the increase in punished and time out responding found with EOS and CDP alone. The tryptophan hydroxylase inhibitor p-chlorophenylalanine (PCPA; 100 mg/kg x 3) linearly increased punished responding for the first week of treatment. CDP with PCPA selectively and significantly increased punished responding above the rates for either treatment alone, but the increases were not as substantial as those with EOS + CDP. The serotonin reuptake inhibitor Wy 25093 reduced increases in time out and punished responding under CDP, and the precursor 5-hydroxytryptophan (5-HTP) counteracted increases in punished responding under PCPA but also substantially reduced rewarded responding. These results provide evidence that both increased GABA and decreased serotonin transmission are involved in the anticonflict effects of CDP, as EOS and PCPA both mimicked and potentiated effects of CDP, while picrotoxin, Wy 25093, and 5-HTP counteracted them.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
867.
Spontaneously hypertensive rats (SHR) exhibit elevated levels of ambulation after transfer to a novel environment compared to the Wistar-Kyoto rat (NR). The present experiment compared long-term activity of SHR and NR in a residential maze to determine whether the SHR exhibit elevated levels of locomotor activity under undisturbed, baseline conditions in addition to enhanced reactivity to stimuli. The SHR were much more active visiting more arms of the maze than the NR during the initial hours following transfer to the maze, and during hours around dark onset and light onset. However, the SHR also exhibited higher levels of activity than the NR under baseline conditions. While the NR visited the arm containing food more frequently than other arms, the SHR exhibited no such preference. These data show that both stimulus-induced and basal levels of ambulation are increased in the SHR compared to its normotensive genetical counterpart.  相似文献   
868.
Exposure to electric shock produces an analgesic reaction (SIA) that is reversed by opiate antagonists ("opioid" SIA) under some conditions but not under other conditions ("nonopioid" SIA). A number of studies using tail-flick to radiant heat as the measure of pain sensitivity have found that a small number of shocks lead to nonopioid SIA, while a large number of shocks produce opioid SIA. In contrast, a small number of shocks have been reported to produce opioid SIA when the Formalin test was used to measure pain reactivity. However, the Formalin test involves administering a chronic pain stimulus (injection of Formalin into the paw) for an extended period before the shocks. Here it is reported that this "preexperimental" stress is sufficient to convert the SIA after a small number of shocks measured by tail-flick to the opioid form.  相似文献   
869.
Two experiments are reported comparing high and low schizotypal normals on divided field tasks of (a) letter recognition and (b) local-global processing. On the former, low schizotypal Ss showed an expected right visual-field superiority, whereas high schizotypal Ss showed the opposite, in that respect resembling schizophrenic patients. A similar reversed asymmetry was found when the two personality types were compared for local and global processing of letter stimuli, high schizotypals being especially unusual in showing superior local processing for stimuli presented in the left visual field. The results are taken as providing further support for the theory of schizotypy put forward in a previous paper.  相似文献   
870.
This paper reports the validation of brief, self-report measures of intrinsic enjoyment and boredom coping. Intrinsic enjoyment is characterized by intense involvement, interest and absorbed concentration; boredom coping is designed to reflect the disposition to restructure one's perceptions and participation in potentially boring activities so as to decrease boredom. Both traits are hypothesized to reflect the capacity for good attentional control across a variety of situations. Reliability was established by test-retest correlation and by an inter-item consistency measurement. Construct validity was established by comparison with previously-validated personality tests, real-life measures (such as Random Activities Experiential Sampling, which involves repeated self-report measures in daily life), as well as with laboratory measures of attention (including the averaged visual evoked potential (EP) and the Continuous Performance Test). Intrinsic enjoyment is significantly correlated with an independent measure of intrinsic involvement (low wish to be elsewhere in one's daily life), the affective experience of potency, self-reports of concentrating well with ease, high ego development, an internal locus of control, lack of boredom susceptibility and certain EP indices of attentional change and ‘cortical’ augmenting. Boredom coping is associated with a higher percent of time actually spent alone, high continuous performance task measures of attentional capacity, and low MMPI and Research Diagnostic Criteria indices of psychopathology.  相似文献   
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