Exploring the space of cognitive architectures

Production systems have been proposed as a candidate for the basic architecture of the human information processor. We consider a number of dimensions along which production systems can vary, and we discuss PRISM, a production system formalism designed to aid cognitive modelers in their exploration of the space of architectures. Examples of PRISM settings are presented in the context of particular models. Finally, some heuristics are suggested for efficiently searching the space of possible architectures.     

Drawing Limits: contemporary views on biotechnology

Biotechnology deals with the stuff of life; living things can be changed and barriers between species broken down. Through biotechnology human beings are ‘playing god’ in ways that have not been possible before. This article discusses some findings of the Biocult project, which investigated the views of 956 young people on risk and safety in relation to biotechnology [1]. The article focuses on the responses of young people aged 11 to 18 to the statement ‘human beings can use science and technology to do what they want’ set in the context of answers to other questions on specific applications. Despite the emphasis on individual freedom of choice found in surveys of personal morality, most young people spontaneously brought in notions of limits and barriers to human action in the field of biotechnology. The ways these limits are justified are of interest as they uncover ethical thinking which may or may not be religious or spiritual.     

Affect intensity and the appraisal of emotion

The present study investigated the association between a personality trait known as affect intensity and the perceived qualities of emotions. Subjects completed the Affect Intensity Measure (AIM), and they rated the phenomenological qualities and causal dimensions of previous emotional experiences involving happiness, pride, anxiety, and hate. The results showed that high and low scorers on the AIM reported different perceptions of certain qualities of the emotional event, independent of the emotion's valence; subjects with high scores on the AIM rated their emotions as higher in intensity, frequency, and vividness of recall. In contrast, further analyses revealed little relation between AIM scores and causal dimension ratings of the emotions. However, within-subject analyses indicated that the emotions did differ in their perceived causes, thus supporting predictions from Weiner's attributional model of emotion. The results are discussed in terms of the need for a complex approach to the study of emotion which incorporates intersubject and intrasubject differences.     

Computer control of memory experiments on a large-scale timesharing system

This paper describes a computer system for running verbal learning and memory experiments using a large-scale timesharing computer. Its application is illustrated by control programs used to set up, execute, and analyze a series of interactive free recall experiments. While limitations of timesharing systems for experimental control surely exist, they can often be removed by simple hardware or software. Further, a large machine can provide significant advantages in cost and software development over dedicated laboratory minicomputers. It is possible to obtain the advantages of both types of systems by introducing local intelligence to provide more precise timing and flexible control of experimental devices, while retaining the power and hardware and software resources of the large machine.     

Constructing blockmodels: How and why

Blockmodel approaches to network analysis as developed by Harrison White are shown to fall in a broader class of established data analysis methods based on matrix permutations (e.g., clique detection, seriation, permutation algorithms for sparse matrices). Blockmodels are seen as an important generalization of these earlier methods since they permit the data to characterize their own structure, instead of seeking to manifest some preconceived structure which is imposed by the investigator (e.g., cliques, hierarchies, or structural balance). General algorithms for the inductive construction of blockmodels thus occupy a central position in the development of the area. We discuss theoretical and practical aspects of the blockmodel search procedure which has been most widely used (CONCOR algorithm). It is proposed that the distinctive and advantageous feature of CONCOR is that it solves what is initially presented as a combinatorial problem (permutations of matrices to reveal zeroblocks) by representing the problem as a continuous one (analysis of correlation matrices). When this representation strategy receives further development, it is predicted that the fairly crude empirical approach of CONCOR will be supplanted by more powerful procedures within this same class.     

The relative accessibility of semantic and deep-structure syntactic concepts

Three experiments were conducted to determine the relative accessibility of semantic and deep-structure syntactic concepts. In Experiment 1, which employed a concept-formation task, subjects learned the concept “deep-structure subject” more slowly than the case concept “experiencer.” In Experiments 2 and 3, which employed a new recognition memory procedure, subjects performed more poorly when the sentences to be remembered were differentiated on the basis of deep-structure syntactic relations than when they were differentiated on the basis of semantic relations. These results favor Fillmore’s case grammar, or another semantically based theory, rather than the “standard theory” of Chomsky in a model of linguistic behavior.     

Abnormal behavior after intracerebral injection of polypeptides from wheat gliadin: Possible relevance to schizophrenia

Accumulating evidence suggests that: (1) gluten-like proteins in cereal grains may produce psychiatric symptoms in schizophrenics as well as in celiac patients; (2) the genotypes for these two disorders may have one or more but not all, genes in common. Gluten fed to treated schizophrenics on a cereal grain-free, milk-free diet exacerbates their symptoms; ingestion of polypeptides resulting from peptic-pancreatic digestion of wheat gliadin (from gluten) produces psychiatric and other symptoms in celiac patients. To test their effect on behavior of normal rats we bypassed the protective barrier systems by intracerebral injection of a potent subfraction of gliadin polypeptides which produces psychiatric symptoms in celiacs. Eighteen exploratory experiments in 4 rats demonstrated that intracerebral injection of these polypeptides may variably produce stereotyped movements, prolonged “chewing in air,” “catelepsy” and seizures, all after an unusually long latent period. The lowest dose producing “catalepsy” was 600 μg, and that for seizures was 500 μg. Since we used a mixture, one or more polypeptides in it may be considerably more potent. The accumulated evidence suggests the following working hypothesis: One or more of the polypeptides produced by peptic-pancreatic digestion of certain glutamine-proline rich food proteins(e.g., cereal grain glutens) are psychotoxic and may enter the brain of the schizophrenic or celiac because the small gut, and possibly other, barrier systems (enzymatic, immunologic, membranous, other) suffer defects of an unknown nature due to one or more abnormal genes common to both diseases; and that the differences in the two diseases are determined largely by the dissimilar components of the genotypes.     

Achievement and adjustment correlates of the matching familiar figures test

To help clarify the relationship between the Matching Familiar Figures (MFF) Test and measures of school achievement and adjustment, 450 children from kindergarten, second, and fifth grades were tested and achievement scores and teacher's ratings of classroom and personal adjustment were obtained. Regardless of grades, MFF latency in most instances did not predict achievement or adjustment. At the kindergarten level the correlations between MFF errors and both achievement and adjustment were significant for most subscales but at second grade correlations were lower and generally nonsignificant except for a few adjustment items. At the fifth grade level the correlations were moderately high but when IQ was partialled out the correlations with achievement and school adjustment dropped to near zero; however, partialling out IQ did not affect the moderate correlations between errors and personal adjustment. The errors score evidencedmore important relationships than the latency scores. The relationship between the MFF and ratings of social and emotional adjustment was consistently higher than the correlations between the MFF and achievement. These results suggest that MFF errors are personalogically relevant and that MFF performance is generally more related to adjustment than achievement.     

Control charts for sequential testing

Control charts facilitating the use of sequential strategies of the updown or staircase type are described. The charts are easy to use and the relevant estimates may be derived very simply from the chart. An example is given in which both the 29.3% and 70.7% points on a response curve are estimated using the Up-Down-Transformed-Response (UDTR) procedure. The charts can be used in psychophysics and are also generally applicable to experiments or control processes involving binary responses.