WHY A BRAIN CAPABLE OF LANGUAGE EVOLVED ONLY ONCE: PREFRONTAL CORTEX AND SYMBOL LEARNING

Abstract. Language and information processes are critical issues in scientific controversies regarding the qualities that epitomize humanness. Whereas some theorists claim human mental uniqueness with regard to language, others point to successes in teaching language skills to other animals. However, although these animals may learn names for things, they show little ability to utilize a complex framework of symbolic reference. In such a framework, words or other symbols refer not only to objects and concepts but also to sequential and hierarchical relationships with other symbols. This process is essential to human mental operations, including language, mathematics, and music. In humans, these operations may have coevolved with the prefrontal area of the cerebral cortex, which is proportionately much larger in humans than in other animals and more intricately linked with other areas of the brain. Analysis of the structure and function of the prefrontal area suggests that it is centrally involved in the operation of higher-order associative relationships involving the subordination of one set of associations to another. This alternate learning strategy apparently appeared at the cost of certain sensory, motor, or limbic abilities. The payoff was symbolic thinking. Humans thus are unique among species, not just for their highly developed language ability but for their odd style of thinking and learning.     

Observing responses maintained by conditional discriminative stimuli.

In a conditional discrimination procedure, pigeons' observing responses were analyzed to examine whether two color stimuli (blue or red), conditionally related to whether each of two line stimuli (vertical or horizontal) accompanied reinforcement or nonreinforcement, functioned as conditioned reinforcers. If a variable-interval (VI) 10-s requirement was fulfilled, an observing response produced onset of a color stimulus. A little later, a line stimulus was presented independently of responding, added to the color stimulus to form a compound stimulus. If 55 s elapsed with a response not having occurred either through 55 s or after the variable-interval 10-s had timed out, one of the color-line compound stimuli was presented independently of responding. To control for sensory reinforcement effects and for earlier entrance to the later link, a simple discrimination procedure also was conducted in which reinforcement was not correlated with the color stimuli but with the line stimuli only. As in the conditional discrimination, the observing response also could produce earlier presentation of blue or red. The observing response occurred more frequently during the conditional discrimination than during the simple discrimination. The results were related to different theoretical accounts of conditioned reinforcement, particularly the information hypothesis.     

CAT选题策略分类概述

选题是计算机化自适应测验（CAT）测试过程的关键环节,选题策略的目标是要达到较高的测量精度,同时也实现试题曝光率控制及其他测验目标的实现.本文根据选题策略的基本原理和衍生发展,将众多CAT选题策略分为五大选题策略系列：Fisher函数系列、K-LI函数系列、α分层系列、贝叶斯系列、b匹配系列;并根据测验目标（测验精度、试题曝光率控制、内容平衡、多条件约束）对这些选题策略进行了细分,并对CAT选题策略的选择思路进行归纳.     

主题信息合理性、语境意义偏向性对汉语歧义句意义建构的影响

两个实验以合理型主题信息条件下的句子为对照材料．其它型主题信息条件下的句子为实验材料,考察合理型和非合理型主题信息条件下汉语歧义句意义建构的时间进程和特点。结果表明：(1)合理型主题信息可以顺利地建构一个稳定的基础心理表征;不合理型主题信息则没有这种效应;矛盾型主题信息则引导读者重构一个新的心理表征。(2)在合理型主题信息条件下,语境主要起到证实主题信息区和歧义区所建构的基础表征的作用;而在不合理型、矛盾型主题信息的条件下,语境的作用首先是验证所建构的基础心理表征和歧义句的意义频率,然后有效建构歧义句的意义。     

智力与信息加工速度研究中的检测时范式

检测时是信息加工速度的重要指标,也是智力与信息加工速度关系的研究领域内一种重要的实验范式。文章在简要介绍反应时范式的基础上,着重介绍了检测时范式的实验任务、基本原理以及检测时与智商之间的关系。同时,通过与反应时范式的比较,讨论了检测时范式在智力与信息加工速度研究中的优点和局限性,以及其在解决相关研究领域问题上的方法学意义。     

Shackling the shoulders of giants

This paper informally summarizes a two-day symposium held at the U.S. National Academy of Sciences in Washington, D.C., September 5–6, 2002. The issue was to what extent the progress of science and societal capacity for continued technological innovation are threatened by excessive protection of intellectual property. Excessive protection creates disadvantages not only for scientists and inventors but also for educators/students and for librarians/clientele. Speakers from a variety of disciplines and institutions agreed unanimously that scientific and technological progress is, indeed, under serious threat. Various opinions were expressed about the degree of threat, currently and prospectively, as well as what counter-measures are best suited to resist undue restrictions on creative uses of scientific and technical data and information. This summary is based entirely on the author’s notes from the symposium, and the commentary offered is his alone. My apologies to the speakers if this paper does not accurately reflect the primary intent of their presentations. The “Suggested Readings” offered at the end are not specific to the speakers’ statements but rather are offered as a general resource to aid further research. The definitive record of the symposium is planned to be available from the National Academies Press as a Proceedings publication in the summer of 2003. John Gardenier is an independent researcher, ethicist and science writer.     

Lateralization of egocentric and allocentric spatial processing after parietal brain lesions

The purpose of this paper was to verify whether left and right parietal brain lesions may selectively impair egocentric and allocentric processing of spatial information in near/far spaces. Two Right-Brain-Damaged (RBD), 2 Left-Brain-Damaged (LBD) patients (not affected by neglect or language disturbances) and eight normal controls were submitted to the Ego-Allo Task requiring distance judgments computed according to egocentric or allocentric frames of reference in near/far spaces. Subjects also completed a general neuropsychological assessment and the following visuospatial tasks: reproduction of the Rey-Osterreith figure, line length judgement, point position identification, mental rotation, mental construction, line length memory, line length inference, Corsi block-tapping task. LBD patients presented difficulties in both egocentric and allocentric processing, whereas RBD patients dropped in egocentric but not in allocentric judgements, and in near but not far space. Further, RBD patients dropped in perceptually comparing linear distances, whereas LBD patients failed in memory for distances. The overall pattern of results suggests that the right hemisphere is specialized in processing metric information according to egocentric frames of reference. The data are interpreted according to a theoretical model that highlights the close link between egocentric processing and perceptual control of action.     

Chaos and God's Abundance: An Ontology of Variety in the Divine Life

The primordial chaos of Genesis 1 may be understood as the Pandemonium Tremendum (or PT), the infinite field of variety or abundance within God. The concept of variety is taken from Claude Shannon's theory of communication. Especially significant is Shannon's notion that communication is the limitation of variety through decision processes. In one model of the divine life suggested by the theory, the PT is the boundless source of potential reaped by an agential God in the act of creation as a communication process. Other models for creation include the PT in a biased mode and creatures themselves as decision agents.     

Two Books for Teachers

Murphy, Nancey and Ellis, George F. R. On the Moral Nature of the Universe: Theology, Cosmology, and Ethics
Haught, John F. Science and Religion: From Conflict to Conversation