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901.
A series of experiments investigated which stimulus properties pigeons use when they discriminate pairs of visual arrays that
differ in numerosity. Transfer tests with novel stimuli confirmed that the birds’ choices were based on relative differences
in numerosity. However, pigeons differed from other species in the non-numerical cues that affected their choices. In human
and non-human primates, numerical discrimination is often influenced by continuous variables such as surface area or overall
stimulus brightness. Pigeons showed little evidence of using those cues, even when summed area and brightness had been correlated
with numerosity differences and reward outcome. But when array-element sizes were asymmetrically distributed across numerosities,
the birds readily utilized information about item sizes as an additional discriminative cue. These novel results are discussed
in relation to pigeons’ tendency to focus on local, rather than global dimensions when they process other non-numerical complex
visual stimuli. The findings suggest there may be inter-specific differences in the type of perceptual information that provides
the input stage for mechanisms underlying numerical processing.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
902.
Many antipredator adaptations are induced by the prey’s ability to recognize chemical cues from predators. However, predator
recognition often requires learning by prey individuals. Iberian green frog tadpoles (Pelophylax perezi) have the ability to learn new potential predators. Here, we tested the memory capabilities of Iberian green frog tadpoles.
We conditioned tadpoles with chemicals cues from a non-predatory fish in conjunction with conspecific alarm cues, and examined
whether tadpoles retained their conditioned response (reduction of activity level). We found that conditioned tadpoles reduced
their activity levels in subsequent exposures to the non-predatory fish cues alone. Tadpoles were able to remember this association
and reduced movement rate at least for 9 days after. The ability to learn and memorize potential predators may be especially
important for the survivorship of prey species that are likely to find a high variety of predators. However, after those 9 days,
there was a lack of response to the non-predatory fish cues alone in the absence of reinforcement. This could be explained
if tadpoles behave according to the threat-sensitive predator avoidance hypothesis, and the perceived risk to the learning
cue diminished over time, or it could be due to an apparent forgetting process to avoid non-adaptative responses to chemical
cues of non-dangerous species that were randomly paired with alarm cues. Thus, this study demonstrates that green frog tadpoles
in the absence of reinforcement remember the chemical cues of a learned predator only for a limited time that may be adaptative
in a threat-sensitive context. 相似文献
903.
Ireen de Graaf Simone Onrust Merel Haverman Jan Janssens 《Infant and child development》2009,18(6):481-501
The present study evaluated two primary care parenting interventions. First, we evaluated the most widely used Dutch practices for primary care parenting support. Second, we assessed the applicability of the Primary Care Triple P approach, which is now being utilized in a wide variety of primary care settings. Both interventions target parents of children with mild to moderate behavioural and/or emotional problems, with the aim of improving parenting skills and thereby decreasing child problems. We examined the interventions in pre‐, post‐ and follow‐up assessment, and compared the results. Both interventions produced significant reductions in reported child emotional and behaviour problems, that also remained after 3 months. For both groups, parenting styles were also found to have improved at both post‐test and follow‐up measurement. When compared with the regular Dutch parenting consultation practices, however, the Primary Care Triple P approach produced greater reductions in parental laxness and total parenting dysfunction, and greater improvement in total parenting competence at both post‐test and follow‐up. Primary Care Triple P may even—in light of the greater improvements in parenting skills and total parental competences in the Triple P group than in the regular Dutch parenting consultation group—produce better results in the long run concerning child behaviour and emotional problems. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
904.
The moderating effect of parental warmth on the association between spanking and child aggression: a longitudinal approach 总被引:1,自引:0,他引:1
Ann Michele Stacks Toko Oshio Jean Gerard Jacqueline Roe 《Infant and child development》2009,18(2):178-194
Using data from the Early Head Start Research and Evaluation Study, this study analysed the stability of child aggressive behaviour beginning in infancy and tested whether spanking when the child was 36 months was associated with aggressive child behaviour among three ethnic groups and whether maternal warmth moderated the effect of spanking on aggressive behaviour in each ethnic group at 36 months, after controlling for earlier aggressive behaviour. Participants included 693 Hispanic parent–child dyads, 1013 African‐American dyads and 1086 Caucasian dyads who met qualifications for participation in the Early Head Start programme. Findings suggest that infant temperament was associated with aggressive behaviour at 24 and 36 months and that child aggression remained stable. Among the three ethnic groups, spanking was only associated with aggressive behaviour for children who had Caucasian mothers and maternal warmth did not moderate the effect of spanking on aggressive behaviour. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
905.
Although considerable progress has been made in improving the acquisition of expressive verbal communication in children with autism, research has documented that a subpopulation of children still fail to acquire speech even with intensive intervention. One variable that might be important in facilitating responding for this nonverbal subgroup of children is the use of antecedent orienting cues. Using a multiple baseline design, this study examined whether individualized orienting cues could be identified, and whether their presentation would result in the production of verbal expressive words. The results showed that this antecedent stimulus control procedure produced improvements in responding to verbal models in all of the children, and subsequent gains in speech for some of the children. Theoretical and applied implications of orienting cues as they relate to antecedent stimulus control for children with autism are discussed. 相似文献
906.
ABSTRACT— Decades of research in Western countries such as the United States have supported the idea that parental control undermines children's psychological development. In recent years, investigators have asked whether this is also true in East Asian countries such as China, given that several aspects of East Asian culture have the potential to make children more accepting of parental control. We review research indicating that the effects of parental control on children's psychological functioning are similarly negative in the United States and China, the two countries where most research on this subject has been conducted. However, we also highlight specific contexts in which the effects may be stronger in the West. 相似文献
907.
Marceline Lee Lynne Vernon‐Feagans Arcel Vazquez Amy Kolak 《Infant and child development》2003,12(5):421-439
This study examined the additive effect of structural variables, child characteristics, and the family environment on mothers' and fathers' work/family role strain. Differences between mothers and fathers on these variables were also examined. The sample consisted of 36 dualearner families whose children had been in daycare from infancy through 4 years of age. Structural variables included work schedules and time spent with child for mothers only, fathers only, and both parents together with child. Child characteristics included temperament and health. Family environment variables included different components of the family environment (conflict, cohesion, expressiveness, organization, and control) and parenting daily hassles. Results showed that mothers' time with child and caregiving for child were greater than fathers'. Mothers reported more expressiveness in the family and more daily hassles with children than fathers. Mothers' level of role strain was also significantly higher than fathers'. For mothers, role strain was associated with hours away from home, child sociability, family conflict, and daily hassles resulting in an R2 of 0.57. Fathers' role strain was associated with family expressiveness, organization, and their wives' daily hassles resulting in an R2 of 0.37. Data suggest that mothers' and fathers' role strain may be driven by somewhat different factors. For women, aspects of the family and the child and work hours accounted for a considerable portion of the variance while for men, only aspects of the family environment were associated with their level of role strain. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
908.
以105名2岁儿童及其母亲为被试,采用实验室录像观察法,探讨在自由游戏情景下母亲教养目标、使用策略及两者的关系.母亲的教养目标分为四个方面:鼓励儿童的独立、鼓励儿童的接近、不鼓励独立和不鼓励接近;根据压力程度的不同将教养策略分为三大类共11种.结果表明:(1)鼓励儿童独立自主活动是母亲在自由游戏情景下的主要教养目标;(2)母亲使用得最多的为中等程度压力策略、其次是低压力的建议策略;(3)与四种教养目标相关密切的为中、低程度压力的教养策略,即建议、解释、积极评价和指导,在否定的教养目标下使用高压力的干扰和坚持要求执行策略. 相似文献
909.
910.
The ability to recognise kin has been demonstrated in several animal species. However, the mechanisms of kin recognition often remain unknown. The most frequently discussed sensory modalities to recognise kin are visual, olfactory and acoustical cues. Three-spined sticklebacks (Gasterosteus aculeatus) are able to differentiate between kin and non-kin when presented visual and olfactory cues combined. To elucidate, which cues they use to recognise kin female sticklebacks were given the choice between two identical computer animations of courting stickleback males. Next to one animation, water conditioned by a brother was added, while near the other, water from an unrelated male was added. In half of the experiments, the brother was familiar while in the other half he was unfamiliar to the female. Both scenarios were carried out with both outbred and inbred fish. The results showed that the females adjusted their choice behaviour according to relatedness. Furthermore, they were able to recognise both familiar as well as unfamiliar brothers. Inbreeding did not affect this ability. Hence, three-spined sticklebacks are able to recognise their relatives using olfactory cues alone. The cognitive mechanisms underlying this ability were independent from familiarity and not impaired by inbreeding. 相似文献