Honeybees (Apis mellifera) holding on to memories: response competition causes retroactive interference effects

Five experiments on honeybees examined how the learning of a second task interferes with what was previously learned. Free flying bees were tested for landmark-based memory in variations on a paradigm of retroactive interference. Bees first learned Task 1, were tested on Task 1 (Test 1), then learned Task 2, and were tested again on Task 1 (Test 2). A 60-min delay (waiting in a box) before Test 2 caused no performance decrements. If the two tasks had conflicting response requirements, (e.g., target right of a green landmark in Task 1 and left of a blue landmark in Task 2), then a strong decrement on Test 2 was found (retroactive interference effect). When response competition was minimised during training or testing, however, the decrement on Test 2 was small or nonexistent. The results implicate response competition as a major contributor to the retroactive interference effect. The honeybee seems to hold on to memories; new memories do not wipe out old ones.     

Generalisation: mechanistic and functional explanations

An overview of mechanistic and functional accounts of stimulus generalisation is given. Mechanistic accounts rely on the process of spreading activation across units representing stimuli. Different models implement the spread in different ways, ranging from diffusion to connectionist networks. A functional account proposed by Shepard analyses the probabilistic structure of the world for invariants. A universal law based on one such invariant claims that under a suitable scaling of the stimulus dimension, generalisation gradients should be approximately exponential in shape. Data from both vertebrates and invertebrates so far uphold Shepard's law. Some data on spatial generalisation in honeybees are presented to illustrate how Shepard's law can be used to determine the metric for combining discrepancies in different stimulus dimensions. The phenomenon of peak shift is discussed. Comments on mechanistic and functional approaches to generalisation are given. Accepted after revision: 10 September 2001 Electronic Publication     

From covariation to causation: a test of the assumption of causal power

How humans infer causation from covariation has been the subject of a vigorous debate, most recently between the computational causal power account (P. W. Cheng, 1997) and associative learning theorists (e.g., K. Lober & D. R. Shanks, 2000). Whereas most researchers in the subject area agree that causal power as computed by the power PC theory offers a normative account of the inductive process. Lober and Shanks, among others, have questioned the empirical validity of the theory. This article offers a full report and additional analyses of the original study featured in Lober and Shanks's critique (M. J. Buehner & P. W. Cheng, 1997) and reports tests of Lober and Shanks's and other explanations of the pattern of causal judgments. Deviations from normativity, including the outcome-density bias, were found to be misperceptions of the input or other artifacts of the experimental procedures rather than inherent to the process of causal induction.     

Detection of bilateral symmetry in complex biological images

The recognition of bilateral symmetry in simple dot patterns is reliably influenced by orientation. Performance is best when the axis of symmetry is vertical. We conducted two experiments to determine whether stimulus orientation also affects detection of the low levels of naturally occurring asymmetry in complex biological images. University students judged whether colour images displayed on a computer monitor possessed perfect bilateral symmetry. Stimuli were generated from high-resolution plan-view images of crabs and insects. In experiment 1, the asymmetric stimuli were the original animals, displayed on a standard black background. Symmetrical versions of each natural image were generated by sectioning the shape at the midline, copying and reflecting one side and then fusing the two halves together. To facilitate comparison of results with those obtained in earlier studies, we also presented dot patterns based upon both the slightly asymmetric and perfectly symmetrical natural images. Experiment 2 was designed to assess whether symmetry detection was dependent upon the markings and patterns on the body and appendages of the animals. The natural images were converted to silhouettes and tested against matched dot patterns. In both studies, images were presented in a random sequence with the axis of symmetry vertical, horizontal, oblique left, and oblique right. Performance with the biological images was consistently better than with the dot patterns. Abolishing fine detail did not appreciably reduce this effect. A pronounced vertical advantage was apparent with all stimuli, demonstrating that this phenomenon is robust despite considerable variation in image complexity. The implications of orientation effects for perception of natural structures are discussed.     

Effects of service robots' anthropomorphism on consumers' attribution toward and forgiveness of service failure

We investigated the effects of service robots' anthropomorphism on consumers' attribution and forgiveness of service failure. By manipulating the levels of anthropomorphism in service robots in three experiments, we evaluated the relationship norms and involvement levels of consumers. Three contributions of our study are as follows. First, most human–robot interaction studies have focused on consumers' dissatisfaction with service robots' service failures. Unfortunately, few studies have investigated the influence of service robots' anthropomorphism levels on consumers' internal attribution and forgiveness of service failure. In the present study, we found a positive correlation between the former and the latter. The findings of this study indicate marketing managers should design their service robots to be less anthropomorphic to reduce the likelihood of consumers making an internal attribution when a service failure occurs and increase their forgiveness of service failure. In addition, to reduce the likelihood of consumers' internal attribution upon service failure, managers may ensure that their service robots explain to the consumers the cause of service failure (e.g., inability to understand consumers' requirements and robots' design-related limitations). Second, consumers' relationship norms moderate the effect of anthropomorphism level on internal attribution. Third, robot anthropomorphism is reportedly effective only when anthropomorphization occurs subconsciously.     

经典测验理论和项目反应理论对题目分析的对比研究

项目反应理论(Item Resporse Theory IRT)被一些人认为是当代心理测量三大发展方向之一。在某些方面,它比经典测验理论(Classical TestTheory CTT)更为合理。本文利用1986年上海市师范类高等院校招生考试的理科数学试卷中选择题的实际考试资料,先用CTT计算有关题目指数,再用IRT对题目绘制题目特征曲线ICC(Item Charicteriotic Curve)并按Logstic模型对题目参数作出了估计,从而对题目分析结果作了对比研究。最后,本文对IRT与CTT在我国的运用、提出了若干看法。     

皮亚杰应是三项图式论者

本文明确提出皮亚杰应是三项图式论者,这涉及到心理学中的许多重大的哲学理论问题。文章分为四个部分:(1)主客体之间的相互作用是以主体活动为中介的;(2)认识信息来源于三项图式构成的环路系统;(3)建构主义的动力机制与三项图式系统的辩证关系;(4)三项图式系统具有客观实在性。总之,皮亚杰的发生认识论并没有违背马克思主义反映论的基本原则。     

Dispositional Optimism in Chinese People: What Does the Life Orientation Test Measure?

The Life Orientation Test was back-translated to Chinese and administered to a sample of college students (N = 314) and a sample of normal adults (N = 306) along with measures of personality and symptoms. When subject to factor analysis, the positive items (representing optimism) and the negative items (representing pessimism) emerged as two separate factors. Empirically, optimism and pessimism were moderately correlated and had unique contributions to the explanation of personality and symptom measures, so that the total score of C-LOT was a better predictor of criterion measures than either optimism or pessimism alone. However, C-LOT's relationship with symptoms was eliminated after negative affectivity was controlled in the student sample, but not in the adult sample, thus suggesting some confounding with negative affectivity. Further research is required to improve the measurement of optimism in Chinese people and to clarify the relationship between optimism and pessimism.     

关于我国学生汉语阅读困难的研究

旨在探讨在我国学生的汉语学习中是否存在阅读困难问题。研究分别采用了目前国外较常使用的两种阅读困难操作定义和新近提出的截点法,对我国学生汉语学习中的阅读困难问题进行了考查。结果揭示出阅读困难在汉语学习者中同样存在,检出率分别为４．５５％和７．９６％．中国学生的阅读困难既表现在词汇上也表现在理解上;研究还发现同为阅读困难者男生和女生呈现出不同的特点。