Memory for two stimulus-response items in pigeons

Six pigeons served in a discrete-trial experiment on short-term memory. Combinations of three key positions and two ordinal positions, yielding six possible sequences of stimulus-response pairs, were used as lists of items. A retention interval separated list presentation from the test phase in which two (for Group 1) or three (for Group 2) keys were illuminated with either red or green light. A reinforcer was delivered if a subject pecked the key of the first item on a red trial and the key of the second item on a green trial. When the retention interval was lengthened from one to five or nine seconds, a systematic loss of stimulus control resulted. Lengthening the interval between items from one to eight seconds had a much smaller effect for the birds in Group 1, whereas a systematic loss of stimulus control was found in red trials for the birds in Group 2. The functional relations between choice accuracy and delay provided an empirical basis for analysis of what relations among temporal events can become discriminative stimuli.     

Reactions following the sudden death of a classmate

Findings from a study of adolescents grief reactions following the sudden death of a friend and a classmate are presented. The group (26 classmates) was followed up after one and nine months. Interviews and a questionnaire including the Imapact of Event Scale and the Hogan Grief Inventory were used. The general grief scores on the Hogan Grief Inventory indicated that the grief level was similar to that of adolescents who had lost siblings. The scores on the Impact of Event Scale showed a descline in distress level from 1 to 9 months. However, after 9 months about 1/5 of the students still scored above a clinical cut-off point indicating post-traumatic stress levels. Recommendations for improving help following such events are presented.     

The effect of question repetition within interviews on young children's eyewitness recall

This study investigated the influence of question repetition and question type (answerable, unanswerable, or opinion seeking) on children's recall. A total of 136 children (5-, 7-, and 9-year-olds) watched a live 15-min presentation. One week later, the children were asked 20 questions that were repeated an additional two times within the interview. Accuracy of children's responses to unanswerable questions declined with repetition. Children were more likely to change a response to an unanswerable question than to an answerable question. Overall, children maintained the same answers to only three-quarters of the repeated questions. The most common pattern of change was for children to change their answer the second time a question was asked and then to maintain that answer when questioned again. The high percentage of changed answers within a single interview has important implications for forensic interviewing.     

Derived stimulus relations, semantic priming, and event-related potentials: testing a behavioral theory of semantic networks

Derived equivalence relations, it has been argued, provide a behavioral model of semantic or symbolic meaning in natural language, and thus equivalence relations should possess properties that are typically associated with semantic relations. The present study sought to test this basic postulate using semantic priming. Across three experiments, participants were trained and tested in two 4-member equivalence relations using word-like nonsense words. Participants also were exposed to a single- or two-word lexical decision task, and both direct (Experiment 1) and mediated (Experiments 2 and 3) priming effects for reaction times and event-related potentials were observed within but not across equivalence relations. The findings support the argument that derived equivalence relations provides a useful preliminary model of semantic relations.     

Mental rotation and temporal contingencies.

A task that requires subjects to determine whether two forms of the same shape, but in different orientations, are mirror images or identical except for orientation is called a handedness recognition task. Subjects' reaction times (RT) on this task are consistently related to the angular disparity (termed alpha) between the two presented forms. This pattern of data has been interpreted to indicate that subjects solve the task by imagining that one of the forms rotates into the orientation of the other (termed mental rotation). The speed with which one imagines one of the forms rotating has been widely considered a fixed capability of the individual, and thus immune to the effect of contingencies. We present an experiment that assesses the effects of temporal contingencies in a handedness recognition task on the slope of the function RT = f(alpha). The data indicate that the slope of this function can come under the control of temporal contingencies.     

认知事件相关电位P_(300)与儿童的智力水平和年龄特征

诱发电位 (EP) ,亦称事件相关电位 (ERP) ,是神经系统活动功能的电生理指标。认知事件相关电位 P3 0 0 作为反映个体大脑认知功能的神经电生理的重要指标已经被许多有关研究所采纳。本研究从神经电生理的角度 ,一方面对认知事件相关电位 P3 0 0 与儿童的智力水平的关系进行测查 ,一方面对认知事件相关电位 P3 0 0 的年龄特点进行研究 ,以期了解和说明儿童认知发展的神经电生理基础及其年龄特征。实验表明 :儿童智力水平与 P3 0 0 各成分潜伏期呈负相关 ,与反映认知功能的主要指标 P3 的负相关达到非常显著水平 (P <0 .0 0 1 ) ,与 P3 0 0 各成分的振幅基本呈正相关 ,儿童不同智力水平之间 ,其反应认知功能的主要指标 P3 的潜伏期差异非常显著。儿童青少年 P3 0 0 的各潜伏期的发展总趋势随年龄增长而下降。其中 ,P3 的潜伏期随年龄增长而下降的趋势更为明显。P3 的振幅则随年龄增长而增大。六个年龄组间 P3 0 0 各成分差异均达到非常显著水平 (P <0 .0 0 1 )。     

Sprachspiel vs. vollständige Sprache

The article formulates a criticism of Wittgenstein's later philosophy which, in its substance, I would like to think, is fairly the same as the (hermeneutic) criticism issued by Apel and Habermas in the sixties. Contrary to these philosophers, however, I try to make the point by focusing on the distinction between language game and language, respectively between intralanguage relations of family resemblance (between language games) and interlanguage translation relations. The notion of a complete language is introduced — completeness of a language being, roughly, its possibility in principle of being translated into any (other) language — and the criticism of Wittgenstein is formulated as the allegation that he does not, or will not, acknowledge such a concept of completeness.So far the contents of the first part of the article. The rest of it assembles some hints, remarks and reminders which bear upon the question of the completeness of a language. These considerations include comments on the conditions of translatability, on the performative (agent's) knowledge or intention-in-action of the acting person, on Habermas' concept of communicative competence and on the notion of a responsible subject of action. It is alleged that to speak of translation and reporting an event as language games is misleading.     

认知事件相关电位P300与儿童青少年工作记忆的发展

研究采用ERP技术对59名儿童工作记忆水平与事件相关电位进行比较分析,以说明工作记忆发展的神经电生理基础及年龄特征。实验仪器为美国NICOLET公司生产的COMPACT FOUR脑诱发电位仪。结果发现:(1)儿童工作记忆水平与P300各成分潜伏期呈负相关,与P300各成分的振幅呈正相关。(2)儿童P300的各潜伏期随年龄增长而下降,振幅随年龄增长而增大。(3)不同性别儿童P300各成分均无显著性差异。     

What constitutes traffic event severity in terms of human danger perception?

This study focuses on the severity gradation of non-collision events. Earlier theoretical work has suggested that a proper severity measure for an event should reflect the risk of personal injury, which is often split into two components, including the risk of a collision and the potential consequences had the collision taken place. While a great number of severity measures have been suggested, most of them fail to address both components, thus resulting in counter-intuitive event gradations and inconclusive outcomes in validation studies. Conversely, it has been shown that human observers often show very good agreement when given a task to rank traffic situations by their severity or level of danger. The aim of this study is to investigate in depth how human judgements of the severity of traffic situations can be expressed by means of objective safety indicators. In this study, a set of video-recorded traffic situations, in which a cyclist passes straight through an intersection while a left or right-turning motor vehicle crosses the cyclist’s path, were analysed. Binary logistic regression was used to develop models assessing the most important traffic severity indicators associated with human feelings of danger. The results showed that the initial conditions of a traffic event, defined as a start of an evasive action, contain the most important information for explaining its severity. Moreover, variables related to both proximity and collision consequences are important and should be integrated into severity measures.