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971.
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   
972.
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   
973.
974.
975.
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   
976.
Rats provided with chronic, continuous access to intracranial self-stimulation (ICS) exhibit discrete episodic response patterns. Response episodes under two conditions were examined for systematic trends in the spacing of times between successive responses (interresponse times; IRTs) to better identify the motivational bases of ICS. Three trends were observed in self-initiated and experimenter-provoked episodes. First, initial responses of spontaneous episodes typically had declining interresponse times. Second, this trend was not present when responses were provoked rather than spontaneous. Third, absolute times between responses varied across conditions, with provoked behavior having significantly lower initial IRTs. The findings suggest that for spontaneously initiated responding a transient facilitatory process cumulates at the beginning of ICS episodes. For provoked responding, it is possible that a manipulation which increased the initial probability of responding over time may have done so by maximizing an initial phasic priming process. At their onset, spontaneous and provoked episodes may be characterized by quantitatively differing motivational profiles.  相似文献   
977.
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   
978.
Recent data on post-war birth cohorts in the U.S.A. show a negative relationship between IQ and fertility, both actual and expected. Previous investigators (e.g. Bajema, the Reeds and Waller) had found a slightly positive relationship for certain pre-war birth cohorts. This secular change in the relationship between IQ and fertility is replicated here for data on the membership of the American Mensa. Members born before the war exhibit a fertility below but close to that of the equivalent cohorts in the nation as a whole. Members born during and after the war exhibit a fertility that is substantially lower than that of the equivalent national cohorts. Apparently, rising fertility, which characterized the period in which the pre-war birth cohorts bore their children, causes a convergence in birth rates across IQ classes. Declining and/or low fertility, which characterizes the period in which the post-war birth cohorts are bearing their children, has the opposite effect, i.e. a divergence in birth rates across IQ classes, with the lower birth rates in the higher-IQ classes. The membership of Mensa may not be a representative sample of the high-IQ population as a whole, as it seems to attract a disproportionate number of low procreators even for this population. However, there is no reason to believe that changes in fertility rates across cohorts within Mensa, relative to changes in the national fertility rates, do not reliably reflect changes in fertility rates across cohorts within the high-IQ population of the U.S.A. as a whole, again relative to those of the nation, though these rates may be fluctuating around different means.  相似文献   
979.
A total of 1505 children (633 boys and 872 girls) completed the I6 Impulsiveness Questionnaire. Reliabilities, scale intercorrelations and means and standard deviations are given after slight modifications were made to the original scoring key on the basis of factor analyses. Age means for both sexes are also given.  相似文献   
980.
Robust lateralization developed in right-handed adults who were asked to judge letter pairs as "same" or "different" during 4608 trials. By the end of the first two blocks (768 trials) "same" responses were favored when presented in the RVF (transmitted directly to the left hemisphere) and "different" responses were favored when presented in the LVF (transmitted direction to the right hemisphere). This gradually reversed over sessions with "same" responses becoming faster for letters presented in the LVF, and "different" responses becoming faster for stimuli presented in the RVF. The laterality acquired under these conditions was cumulative and reproducible, appeared in all 16 subjects, and was preserved between sessions a week apart. The data suggest that laterality is a flexible and reversible characteristic of the human brain even when stimulus and task remain constant.  相似文献   
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