Category labels versus feature labels: Category labels polarize inferential predictions

What makes category labels different from feature labels in predictive inference? This study suggests that category labels tend to make inductive reasoning polarized and homogeneous. In two experiments, participants were shown two schematic pictures of insects side by side and predicted the value of a hidden feature of one insect on the basis of the other insect. Arbitrary verbal labels were shown above the two pictures, and the meanings of the labels were manipulated in the instructions. In one condition, the labels represented the category membership of the insects, and in the other conditions, the same labels represented attributes of the insects. When the labels represented category membership, participants’ responses became substantially polarized and homogeneous, indicating that the mere reference to category membership can modify reasoning processes.     

Category representation for classification and feature inference

This research's purpose was to contrast the representations resulting from learning of the same categories by either classifying instances or inferring instance features. Prior inference learning research, particularly T. Yamauchi and A. B. Markman (1998), has suggested that feature inference learning fosters prototype representation, whereas classification learning encourages exemplar representation. Experiment 1 supported this hypothesis. Averaged and individual participant data from transfer after inference training were better fit by a prototype than by an exemplar model. However, Experiment 2, with contrasting inference learning conditions, indicated that the prototype model was mimicking a set of label-based bidirectional rules, as determined by the inference learning task demands in Experiment 1. Only the set of rules model accounted for all the inference learning conditions in these experiments.     

Category dimensionality and feature knowledge: when more features are learned as easily as fewer

Three experiments compared the learning of lower-dimensional family resemblance categories (4 dimensions) with the learning of higher-dimensional ones (8 dimensions). Category-learning models incorporating error-driven learning, hypothesis testing, or limited capacity attention predict that additional dimensions should either increase learning difficulty or decrease learning of individual features. Contrary to these predictions, the experiments showed no slower learning of high-dimensional categories; instead, subjects learned more features from high-dimensional categories than from low-dimensional categories. This result obtained both in standard learning with feedback and in noncontingent, observational learning. These results show that rather than interfering with learning, categories with more dimensions cause individuals to learn more. The authors contrast the learning of family resemblance categories with learning in classical conditioning and probability learning paradigms, in which competition among features is well documented.     

Tracking a movement: U.S. milestones in suicide prevention

Suicidology and suicide prevention are relatively new fields of study in the United States, but they have made significant progress since their beginnings. This study aimed to identify the most impactful theories in the history of science and suicidology and the most impactful events in the suicide prevention movement. These theories and events were identified through expert nomination. The most impactful theories were those of Shneidman, Durkheim, and Joiner. The most impactful events included the opening of the first suicide prevention center and hotline, the founding of the American Association of Suicidology, and national publications (e.g., National Strategy for Suicide Prevention).     

Verb movement in acquisition and aphasia: same problem, different solutions-evidence from Dutch

This paper focuses on verb movement in agrammatism and child language. We present data from a sentence completion experiment with 6 Dutch agrammatic aphasics and 21 Dutch-speaking children. The experiment compares completion of matrix clauses (which require verb movement) and embedded clauses (where such movement is not required) in these two populations. The results reveal a clear asymmetry: Both agrammatics and children do very well with embedded clauses but fail in 50% with the matrix clauses. It is concluded that the problem which both populations are facing is one of verb movement rather than verb inflection. An error analysis of the responses reveals that, although both agrammatics and children try to avoid movement, they apply different strategies to achieve this goal.     

MICELAB: Spatial processing of mouse movement in Turbo Pascal

Pointing tasks with a mouse are very useful in psychological experiments concerned with a subject’s ability to track a visual object or to move to a target location (e.g., to find a word in text). Such tasks are quite easily performed by subjects, and numerous variables may be obtained from the mouse movement. In this article we describe a set of Turbo Pascal 6.0 units and a program running on the IBM PC family that show how data (x,y coordinates) recorded from a mouse movement can be analyzed to give dispersion, direction, and distance of the movement.     

知识背景效应对分类加工过程影响的眼动研究

在目标匹配范式下,使用表示现实生活中的物体和场景关系的手绘黑白图片材料,通过眼动记录法考察了68名知识背景不同的文理科大学生分类加工过程的差异。结果表明,知识背景对大学生分类加工过程有影响,其主要作用于分类加工的首次加工阶段。文科学生在首次加工中对问题区分配的注意多于选项区,而理科学生对问题区和选项区平均分配注意。文科生相对于理科生能够更早的注意到正确选项,在加工中重视对上位概念概括(问题区目标概念)和下位概念与上位概念间(选项区待分类概念和目标概念)的比较,而理科生更加重视同水平概念间的比较。     

Carrot eaters or moving heads: inductive inference is better supported by salient features than by category labels

How do words affect generalization, and how do these effects change during development? One theory posits that even early in development, linguistic labels function as category markers and thus are different from the features of the stimuli they represent. Another theory holds that early in development, labels are akin to other features, but that they may become category markers in the course of development. We addressed this issue in two experiments with 4- to 5-year-olds and adults. In both experiments, participants performed a categorization task (in which they predicted a category label) and an induction task (in which they predicted a missing feature). In the latter task, the category label was pitted against a highly salient feature, such that reliance on the label and reliance on the salient feature would result in different patterns of responses. Results indicated that children relied on the salient feature when performing induction, whereas many adults relied on the category label. These results suggest that early in development, labels are no more than features, but that they may become category markers in the course of development.     

Fake hand in movement: Visual motion cues from the rubber hand are processed for kinesthesia

The feeling that a fake (e.g. rubber) hand belongs to a person's own body can be elicited by synchronously stroking the fake hand and the real hand, with the latter hidden from view. Here, we sought to determine whether visual motion signals from that incorporated rubber hand would provide relevant cues for sensing movement (i.e. kinesthesia). After 180 s of visuo-tactile synchronous or asynchronous stroking, the fake hand was moved along the lateral or the sagittal axis. After synchronous stroking, movement of the rubber hand induced illusory movement of the static (real) hand in the same direction; the illusion was slightly more frequent and more intense when the fake hand was moved along the sagittal axis. We therefore conclude that visual signals of motion originating from the rubber hand are integrated for kinesthesia by the central nervous system just as visual signals from the real hand are.     

Category induction in autism: Slower,perhaps different,but certainly possible

Available studies on categorization in autism indicate possibly intact category formation, performed through atypical processes. Category learning was investigated in 16 high-functioning autistic and 16 IQ-matched nonautistic participants, using a category structure that could generate a conflict between the application of a rule and exemplar memory. Same–different and matching-to-sample tasks allowed us to verify discrimination abilities for the stimuli to be used in category learning. Participants were then trained to distinguish between two categories of imaginary animals, using categorization tests early in the training and at the end (160 trials). A recognition test followed, in order to evaluate explicit exemplar memory. Similar discrimination performance was found in control tasks for both groups. For the categorization task, autistic participants did not use any identifiable strategy early in the training, but used strategies similar to those of the nonautistic participants by the end, with the same level of accuracy. Memory for the exemplars was poor in both groups. Our findings confirm that categorization may be successfully performed by autistics, but may necessitate longer exposure to material, as the top-down use of rules may be only secondary to a guessing strategy in autistics.     

Additions are biased by operands: evidence from repeated versus different operands

Recent evidence led to the conclusion that addition problems are biased towards overestimation, regardless of whether information is conveyed by symbolic or non-symbolic stimuli (the Operational Momentum effect). The present study focuses on the role of operands in the overestimation of addition problems. Based on the tie effect, and on recent evidence that the nature of operands biases addition problems towards an underestimation when operands are repeated, but towards an overestimation when different, we aim here to further elucidate the contribution of operands to addition problems. Experiment 1 replicates the underestimation of repeated-operand additions and overestimation of different-operand additions, with large numbers (around 50), and explores whether these effects also apply to small operand additions (around 10). Experiment 2 further explores the overestimation of different-operand additions by investigating the roles of operand order and numerical distance between operands. The results show that both factors have an impact on the overestimation size, but are not crucial for overestimation to occur. The results are discussed in terms of arithmetic strategies, spatial organization of numbers and magnitude representation.     

Attributional inference across cultures: similar automatic attributions and different controlled corrections

Five studies examined the automatic and controlled components of attributional inference in U.S. and East Asian (EA) samples. Studies 1 through 3 used variations of the "anxious woman" paradigm, manipulating the inferential goal (dispositional or situational) and the normative impact of situational constraint information (discounting or augmenting). In each study, U.S. and EA participants under cognitive load produced strong automatic attributions to the focus of their inferential goal (dispositional or situational). Compared with the U.S. cognitive load participants, U.S. no load participants corrected their attributions according to the normative rules of inference. In contrast, EA no load participants corrected in the direction of situational causality, even when the specific content of the situational information provided should have promoted stronger dispositional inferences. Studies 4 and 5 examined and ruled out alternative accounts. Results are discussed in terms of a situational causality heuristic present in EA individuals.     

Inhibition of feature extraction with multiple instances of the target feature in different orientations

Summary Analyses of alphabetic confusion matrices have produced feature lists defined in terms of confusability of characters thought to contain them. Identical shapes of low confusability (e.g., b, d, p, q) therefore share few or no features. Several researchers have observed mutual inhibition of feature extraction with simultaneously presented confusable shapes. Mutual inhibition observed in the current experiments provides a basis for a definition of features in terms of orientation-independent structural relationships. In the first experiment, four alphanumeric characters were each confused with one other character in this same set; however, when another set was formed by reorienting some of these same shapes to become different characters (e.g., 6 to 9), these confusions disappeared. In the second experiment, characters within each set were exposed parafoveally in pairs to different groups of subjects. If members of a pair were similar in shape (disregarding orientation), identification accuracy was poorer than if they were not. Similar shapes in the same orientation were not signficantly more mutually inhibiting than similar shapes in different orientations.     

Same faces, different labels: Generating the cross-race effect in face memory with social category information

Recognition of own-race faces is superior to recognition of other-race faces. In the present experiments, we explored the role of top-down social information in the encoding and recognition of racially ambiguous faces. Hispanic and African American participants studied and were tested on computer-generated ambiguous-race faces (composed of 50 % Hispanic and 50 % African American features; MacLin & Malpass, Psychology, Public Policy, and Law 7:98–118, 2001). In Experiment 1, the faces were randomly assigned to two study blocks. In each block, a group label was provided that indicated that those faces belonged to African American or to Hispanic individuals. Both participant groups exhibited superior memory for faces studied in the block with their own-race label. In Experiment 2, the faces were studied in a single block with no labels, but tested in two blocks in which labels were provided. Recognition performance was not influenced by the labeled race at test. Taken together, these results confirm the claim that purely top-down information can yield the well-documented cross-race effect in recognition, and additionally they suggest that the bias takes place at encoding rather than testing.     

婴儿期母语音位范畴习得：来自言语知觉的证据

婴儿期言语知觉研究表明婴儿最初（1~4个月）可以分辨几乎所有的语音范畴对比;随母语经验增加,婴儿言语知觉逐渐表现出母语语音特征的影响,辅音知觉表现为对母语语音范畴界限敏感性的提高和对非母语范畴界限敏感性的下降,非母语范畴开始同化到母语音系中去,母语元音知觉表现出知觉磁体效应。这些证据表明婴儿逐渐习得母语音位范畴,音位范畴习得顺序可能依赖范畴例子本身的声学特征、发生频率等因素     

Thresholds for movement direction: Two directions are less detectable than one

Thresholds for detecting movement direction were measured for two different types of dynamic dot display; first, one in which all dots moved upwards, and secondly, one in which half the dots moved upwards and half moved downwards. Direction sensitivity was found to be worse for the stimulus containing two simultaneous directions of motion than for the stimulus in one direction. These data are taken as evidence of some form of competition, or AND-NOT gating, between the outputs of direction-specific analysers during threshold determination.