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171.
Decade breaks in the mental number line? Putting the tens and units back in different bins. 总被引:4,自引:0,他引:4
Most models of number recognition agree that among other number representations there is a central semantic magnitude representation which may be conceptualized as a logarithmically compressed mental number line. Whether or not this number line is decomposed into different representations for tens and units is, however, controversial. We investigated this issue in German participants in a magnitude comparison (selection) task in which the larger of two visually presented Arabic two-digit numbers had to be selected. Most importantly, we varied unit-decade-compatibility: a number pair was defined as compatible if the decade magnitude comparison and the unit magnitude comparison of the two numbers would lead to the same response (e.g. 52 and 67) and as incompatible if this was not the case (e.g. 47 and 62). While controlling for overall numerical distance, size and other variables, we consistently found compatibility effects. A control experiment showed that this compatibility effect was not due to perceptual presentation characteristics. We conclude that the idea of one single number line representation that does not additionally assume different magnitude representations for tens and units is not sufficient to account for the data. Finally, we discuss why decade effects were not found in other experimental settings. 相似文献
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175.
The authors refer to the biochemical investigation of the occurrence and metabolism of essential fatty acids in the CNS and to significant differences in results between those obtained in animal experiments and those involving human beings, taking into account hypotheses that have not yet met with general acceptance. Discussed is the possible connection between eicosanic acid and schizophrenia, notably Horrobin's hypothesis of PGE1 deficiency in schizophrenic patients. The probability of a pathogenetic connection between changes in the metabolism of fatty acids and the occurrence of endogenous psychoses is assumed. 相似文献
176.
Patients who were free from seizures and not in possession of a driving license were examined for reasons for their being considered unfit to drive at an outpatient care centre for epileptics catering for 477 patients. The composition of the group was analyzed in respect of age, sex, intake of pharmaceuticals, risk factors and appropriateness of behaviour in traffic. Corresponding conclusions are drawn. 相似文献
177.
F Drago B Bohus R Bitetti U Scapagnini J M van Ree D de Wied 《Behavioral and neural biology》1986,46(1):99-105
Rats with endogenous hyperprolactinaemia, as induced by pituitary homografts under the kidney capsule, displayed increased grooming behavior as compared to that of sham-operated animals. Twelve days after surgery, intracerebroventricular injection of anti-prolactin serum (dilution 1:100, 1 microliter) suppressed the excessive grooming of homografted rats. These observations suggest that prolactin from a peripheral source may reach the central nervous system to affect brain mechanisms involved in grooming behavior. 相似文献
178.
The effect of hippocampal denervation on olfactory memory in rats was tested after interrupting the lateral olfactory tract projections at the level of the entorhinal cortex. When lesioned animals were trained to learn new odors, they showed no evidence of retention 3 h after acquisition. These results confirm earlier data on rapid forgetting in rats after hippocampal deafferentation and are in parallel to the anterograde amnesia typically found in humans with hippocampal damage. On the other hand, preoperatively learned information was minimally impaired after hippocampal deafferentation even if it was acquired within less than 1 h before the lesion. This finding differs from reports on humans as well as monkeys with hippocampal damage where memories formed during a critical time span of months or even years before the lesion are found to be impaired. This may suggest that the consolidation process in humans and rodents has different time scales or that the roles of the human and the rat hippocampal structure in memory formation are somewhat different. 相似文献
179.
Mating-induced inhibition of receptivity in the female golden hamster. I. Short-term and long-term effects 总被引:1,自引:0,他引:1
Female golden hamsters (Mesocricetus auratus) which have actively terminated mating with one male will respond in succession to two or more novel males. However, mating with the first male results in a reduction in receptivity shown toward a second male, with the size of the decrease being proportional to the amount of copulatory stimuli provided by the first male. Furthermore, the decreased receptivity shown toward the second male results in his achieving fewer ejaculations. These effects are more pronounced when the second mating occurs 5 min or 8 h after the first mating than when it occurs 1 or 4 h later, suggesting both short-term and long-term inhibitory effects. Copulation with a single male also effects a 40% shortening of behavioral receptivity. In a promiscuous species such as the hamster, prolonged copulation by the male may enhance the short-term inhibition of female receptivity, thereby reducing the risk of subsequent sperm displacement. The long-term effect occurs too late to affect sperm competition and may, instead, function to reduce the risk of predation as a result of unnecessary further mating. 相似文献
180.