Flexible cue use in food-caching birds

An animal’s memory may be limited in capacity, which may result in competition among available memory cues. If such competition exists, natural selection may favor prioritization of different memory cues based on cue reliability and on associated differences in the environment and life history. Food-caching birds store numerous food items and appear to rely on memory to retrieve caches. Previous studies suggested that caching species should always prioritize spatial cues over non-spatial cues when both are available, because non-spatial cues may be unreliable in a changing environment; however, it remains unclear whether non-spatial cues should always be ignored when spatial cues are available. We tested whether mountain chickadees (Poecile gambeli), a food-caching species, prioritize memory for spatial cues over color cues when relocating previously found food in an associative learning task. In training trials, birds were exposed to food in a feeder where both spatial location and color were associated. During subsequent unrewarded test trials, color was dissociated from spatial location. Chickadees showed a significant pattern of inspecting feeders associated with correct color first, prior to visiting correct spatial locations. Our findings argue against the hypothesis that the memory of spatial cues should always take priority over any non-spatial cues, including color cues, in food-caching species, because in our experiment mountain chickadees chose color over spatial cues. Our results thus suggest that caching species may be more flexible in cue use than previously thought, possibly dependent upon the environment and complexity of available cues.     

Comparing black-capped (Poecile atricapillus) and mountain chickadees (Poecile gambeli): use of geometric and featural information in a spatial orientation task

Since Cheng (Cognition 23:149–178, 1986) first proposed the “geometric module” in rats, a great deal of research has focused on how other species use geometric information and how geometric encoding may differ across species. Here, hand-reared and wild-caught black-capped chickadees and wild-caught mountain chickadees searched for food hidden in one corner in a rectangular environment. Previous research has shown that mountain chickadees do not spontaneously encode geometric information when a salient feature is present near the goal location. Using a slightly different training and testing procedure, we found that both hand-reared and wild-caught black-capped chickadees encoded geometric information, even in the presence of a salient landmark. Some, but not all, mountain chickadees also encoded geometric information. Overall, our results suggest that use of geometric information may be a less preferred strategy for mountain chickadees than for either wild-caught or hand-reared black-capped chickadees. To our knowledge, this is the first direct interspecies comparison of use of geometric information in a spatial orientation task.     

Spatial cognition in the gerbil: computing optimal escape routes from visual threats

Previous studies in our laboratory have shown that when presented with a sudden stimulus simulating an oncoming predator, Mongolian gerbils can compute the optimal trajectory to a safe refuge, taking into account the position of the threat, the location of a clearly visible refuge, and several other contextual variables as well. In the present studies, the main goal was to explore the abilities of gerbils to use mental representations of spaces that were visually occluded by opaque barriers to compute efficient escape trajectories. In all studies, gerbils were placed into a round open field containing a single refuge. On each trial, an overhead visual stimulus was caused to ‘fly’ overhead, eliciting robust escape movements from the gerbils. By manipulating the shape and position of a series of opaque barriers that were interposed between the gerbils and the refuge, we were able to show that gerbils can compute the shortest route to an invisible target, even when the available routes to the target are made complex by using elaborate barrier shapes. These findings suggest that gerbils can maintain representations of their locations with respect to salient environmental landmarks and refuges, even when such locations are not continuously visible.     

Metaphysics and Morality in Neo-Confucianism and Greece: Zhu Xi, Plato, Aristotle, and Plotinus

If Zhu Xi had been a western philosopher, we would say he synthesized the philosophies of Plato, Aristotle, and Plotinus: that he took from Plato the theory of forms, from Aristotle the connection between form and empirical investigation, and from Plotinus self-differentiating holism. But because a synthesis abstracts from the incompatible elements of its members, it involves rejection as well as inclusion. Thus, Zhu Xi does not accept the dualism by which Plato opposed to the rational forms an irrational material principle, and does not share Aristotle’s irreducible dualism between form and prime matter, or his teleology. Neither does he share Plotinus’ indifference to the empirical world. Understanding how these similarities and differences play out against one another will help us discover what is at stake in their various commitments.     

大学生思维方式与应对方式的关系研究

运用思维方式问卷和应对方式问卷对663名大学生进行测试,旨在从文化视角探讨大学生思维方式的特点及其与应对方式的关系。结果表明:(1)大学生思维方式在专业、地域、年级等人口统计变量上存在显著差异:文科生思维的整体性显著高于理工科和艺术类;南方人思维的变化性显著高于北方人;大二学生思维的整体性显著高于大一和大三,大一思维的变化性显著高于大四年级。(2)思维方式对应对方式具有显著的预测作用。其中,协变性对积极应对正向作用显著、对消极应对中的自责和合理化负向作用显著;矛盾性对积极应对负向作用显著、对消极应对正向作用显著。思维的整体性和变化性针对性较强:整体性有助于解决问题的积极应对,变化性可有效避免自责、幻想、合理化的消极应对方式。     

心算应激与特质焦虑、应对风格的关系

选取38名大学生为被试,采用BIOPAC多导生理记录仪,探讨心算应激对不同人格特质和应对风格的大学生心率（HR）、心率变异性（HRV）及皮肤电反应（GSR）的影响。实验采取2（人格特质：特质焦虑、非特质焦虑）×2（应对风格：注重情绪的应对、注重问题的应对）×3（实验阶段：基线期、任务期、恢复期）的三因素混合设计,要求所有被试经历5分钟的基线期、10分钟的心算任务期和5分钟的恢复期。结果表明：（1）特质焦虑的个体和注重情绪应对的个体在心算应激后的短时间内难以恢复到基线期的生理水平;（2）特质焦虑且注重情绪应对的个体在HR、HF、LF/HF及GSR上表现出明显强的反应性和弱的恢复性;（3）非特质焦虑且注重问题应对的个体在HF和GSR上表现出明显弱的反应性,在LF/HF和GSR上表现出明显强的恢复性。     

Flexible use of spatial cues in the southern flying squirrel (<Emphasis Type="Italic">Glaucomys volans</Emphasis>)

Insects, birds, and mammals have been shown capable of encoding spatial information in memory using multiple strategies or frames of reference simultaneously. These strategies include orientation to a goal-specific cue or beacon, to the position of the goal in an array of local landmarks, or to its position in the array of distant landmarks, also known as the global frame of reference. From previous experiments, it appears that birds and mammals that scatter hoard rely primarily on a global frame of reference, but this generalization depends on evidence from only a few species. Here we examined spatial memory in a previously unstudied scatter hoarder, the southern flying squirrel. We dissociated the relative weighting of three potential spatial strategies (beacon, global, or relative array strategy) with three probe tests: transposition of beacon and the rotation or the expansion of the array. The squirrels’ choices were consistent with a spatial averaging strategy, where they chose the location dictated by at least two of the three strategies, rather than using a single preferred frame of reference. This adaptive and flexible heuristic has not been previously described in animal orientation studies, yet it may be a common solution to the universal problem of encoding and recalling spatial locations in an ephemeral physical landscape.     

Spider monkey ranging patterns in Mexican subtropical forest: do travel routes reflect planning?

Although it is well known that frugivorous spider monkeys (Ateles geoffroyi yucatanensis) occupy large home ranges, travelling long distances to reach highly productive resources, little is known of how they move between feeding sites. A 11 month study of spider monkey ranging patterns was carried out at the Otochma’ax Yetel Kooh reserve, Yucatán, Mexico. We followed single individuals for as long as possible each day and recorded the routes travelled with the help of a GPS (Global Positioning System) device; the 11 independently moving individuals of a group were targeted as focal subjects. Travel paths were composed of highly linear segments, each typically ending at a place where some resource was exploited. Linearity of segments did not differ between individuals, and most of the highly linear paths that led to food resources were much longer than the estimate visibility in the woodland canopy. Monkeys do not generally continue in the same ranging direction after exploiting a resource: travel paths are likely to deviate at the site of resource exploitation rather than between such sites. However, during the harshest months of the year consecutive route segments were more likely to retain the same direction of overall movement. Together, these findings suggest that while moving between feeding sites, spider monkeys use spatial memory to guide travel, and even plan more than one resource site in advance. This contribution is part of the special issue “A Socioecological Perspective on Primate Cognition” (Cunningham and Janson 2007).     

The impact of landmark properties in shaping exploration and navigation

This study was aimed at uncovering physical and geometric properties that make a particular landmark a target of exploration and navigation. Rats were tested in a square open-field arena with additional portable corners featuring the same properties as the arena corners. It was found that the routes of progression converged upon the added corners, whether located at the arena wall or the arena center. Route convergence upon the added corners involved numerous visits to these corners. However, time spent at the added corners was relatively short compared with the arena corners, including that from which rats were introduced into the arena. There was no differential effect of testing rats in light or dark, or with a low versus a high portable corner. It is suggested that the added corners were distinct against the background of the arena enclosure, whereas the four arena corners and walls were encoded by the rats as one geometric module. This distinctness, together with the greater accessibility of the added corners, made them salient landmarks and a target of exploration. Thus, the impact of a landmark extended beyond its specific self-geometry to include accessibility and distinctness, which are contextual properties. In addition to the contextual impact on locomotor behavior there was also a temporal effect, with security initially dominating the rats’ behavior but then declining along with an increased attraction to salient landmarks. These spatiotemporal patterns characterized behavior in both lit and dark arenas, indicating that distal cues were secondary to local proximal cues in shaping routes.     

中国青少年心理健康素质·归因风格的研究

应用《青少年心理健康素质调查表·归因风格分量表》对全国23个省市地区的44063名青少年进行了调查,对不同年级阶段青少年归因风格的发展特点进行了分析。结果发现：（1）青少年归因风格的发展存在明显的阶段性,随着年级的升高,其内在归因倾向逐渐减弱;（2）在不同年级阶段,青少年归因风格不同维度的发展方向具有一致性。