Matching, maximizing, and the behavioral unit: concurrent reinforcement of response sequences.

Pigeons pecked two keys in a probability matching situation in which four two-peck sequences were intermittently reinforced: left-left, left-right, right-left and right-right. In Phase 1, relative reinforcement rate was varied with respect to the first response of a sequence: reinforcers were differentially assigned for left-left and left-right sequences as opposed to right-left and right-right sequences. The second response of reinforced sequences occurred equally on the left and right keys across conditions. In Phase II, relative reinforcement rate was varied for sequences that involve an alternation as opposed to those that did not. The relative outputs of the different sequences matched the relative reinforcement rates for the different sequences in both phases. Relative response rates for key pecks did not always match relative reinforcement rates. The intertrial interval separating responses was varied in both phases; increases in the intertrial interval affected the relative frequency of different sequences. The results demonstrate that response sequences acted as functional units influencing choice and thus support a structural account of choice. At the same time, the matching of relative sequence proportion and relative reinforcement rate supports a matching account.     

THE INSULAR MOTHER: HER PROBLEMS IN PARENT-CHILD TREATMENT

Eighteen mother-child dyads were referred for psychological help because of the children's oppositional behaviors and the mothers' aversive reactions to the children. All dyads were from low income families in which the mothers reported themselves to be relatively isolated from social contact in their communities. Following a baseline phase, the mothers were trained to modify their children's oppositional behaviors through time out and a point system. Fourteen of the dyads were observed in three phases of the study: baseline, parent training or treatment, and a 1-year follow-up period. In Phases one and two, child opposition and mother aversive reactions to the children were measured twice weekly by professional observers in the home settings. During Phase three (follow-up), these observations occurred twice per month. In addition, the mothers' self-reported contacts with people in their communities were obtained immediately after each observation. Results showed significant improvement in the mother-child problems during the parent training or treatment phase. However, the problems returned to baseline levels of occurrence during the follow-up phase. The self-report findings indicated that number of mother contacts with friends was an inverse predictor of these problems. On days marked by high proportions of friend contacts, mother-child problems were lower in frequency than on days marked by low proportions of friend contacts. These correlational findings were taken to suggest that a mother's extra-family social contacts may influence her child interaction patterns at home. This possibility was discussed as a factor in the long-term success of parent training as a treatment strategy.     

德性自我意象、道德情绪与行为自我管理：对大学生的一项交叉滞后研究

研究采用交叉时序滞后设计,以问卷法对363名大学生进行了6个月的追踪调查,考察了德性自我意象、道德情绪（内疚/羞愧）与行为自我管理之间的相互预测关系。结果表明,德性自我意象、内疚和羞愧均能显著地正向预测道德行为自我管理,德性自我意象、内疚和羞愧可能是道德行为自我管理的前因变量。     

Structure of the Wechsler Adult Intelligence Scale – Revised in the Italian Normal Standardisation Sample

Six multifactor correlated traits models and a single-factor model of the WAIS-R's factor pattern were examined by confirmatory maximum likelihood factor analyses of a data matrix from the WAIS-R's Italian normative sample raw scores (N=2284). The main aim was to identify what model(s) best fit(s) the data for the different age groups considered. Analyses were designed to determine which of seven hypothesised factor solutions best explained the intellectual ability of four age bands (16 to 74 years of age) and of all samples. Results showed the same three-correlated-factors model (Verbal, Performance, and Freedom From Distractibility) for the younger (16 to 24 years of age) and for more aged (65 to 74 years of age), and two different three-factor models for the adult (band from 25 to 64 years of age) that had in common the presence of Digit Symbol loading on Freedom From Distractibility, that in the younger and aged band loaded on Perceptual Organisation. The individuals may use different strategies when performing a given task on the WAIS-R. Such differences in latent variability may represent real differences in neuropsychological functioning, and as such can account for some of the variability in results noted in the literature. Differences in latent variability across distinct demographic and clinical groups could provide important insight into brain–behaviour relationships.     

Genetic Studies of Autism: From the 1970s into the Millennium

Reviewers in the 1960s and early 1970s were skeptical about any substantial role for genetic factors in the etiology of autism. A realization that the 2% rate of autism in siblings (as estimated at that time) was far above the general population base rate, and that this suggested a possible high genetic liability, led to the first small-scale twin study of autism. The replicated evidence from both twin and family studies undertaken in the 1970s and 1980s indicated both strong genetic influences and the likelihood that they applied to a phenotype that was much broader than the traditional diagnostic category of autism. Medical and chromosomal findings also indicated genetic heterogeneity. Advances in molecular genetics led to genome-wide scans of affected relative pair samples with a positive log of the odds to base 10 score for a location on chromosome 7. The major remaining research challenges and the likely clinical benefits that should derive from genetic research are considered in relation to both current knowledge and that anticipated to emerge from research over the next decade.     

兼职蛋白质及其哲学思考

在蛋白质组学天空中,新近提出的兼职蛋白质概念正越来越受到人们的关注。研究发现,某些蛋白质因其细胞定位、细胞类型、寡聚状态的不同及其配体、底物、辅因子和产物在细胞内浓度的变化而表现出不同的功能,从而对细胞和机体产生诸多有益作用,并使其发展出一系列完善机制以实现不同功能间的转换。兼职蛋白质概念的提出不仅改变了一个基因－－一种蛋白质－－一种功能的传统观念,也为大分子间相互作用、细胞复杂性及生物多样性研究     

Every reinforcer counts: reinforcer magnitude and local preference

Six pigeons were trained on concurrent variable-interval schedules. Sessions consisted of seven components, each lasting 10 reinforcers, with the conditions of reinforcement differing between components. The component sequence was randomly selected without replacement. In Experiment 1, the concurrent-schedule reinforcer ratios in components were all equal to 1.0, but across components reinforcer-magnitude ratios varied from 1:7 through 7:1. Three different overall reinforcer rates were arranged across conditions. In Experiment 2, the reinforcer-rate ratios varied across components from 27:1 to 1:27, and the reinforcer-magnitude ratios for each alternative were changed across conditions from 1:7 to 7:1. The results of Experiment 1 replicated the results for changing reinforcer-rate ratios across components reported by Davison and Baum (2000, 2002): Sensitivity to reinforcer-magnitude ratios increased with increasing numbers of reinforcers in components. Sensitivity to magnitude ratio, however, fell short of sensitivity to reinforcer-rate ratio. The degree of carryover from component to component depended on the reinforcer rate. Larger reinforcers produced larger and longer postreinforcer preference pulses than did smaller reinforcers. Similar results were found in Experiment 2, except that sensitivity to reinforcer magnitude was considerably higher and was greater for magnitudes that differed more from one another. Visit durations following reinforcers measured either as number of responses emitted or time spent responding before a changeover were longer following larger than following smaller reinforcers, and were longer following sequences of same reinforcers than following other sequences. The results add to the growing body of research that informs model building at local levels.     

医学分子生物学的发展历程和展望

回顾了医学分子生物学的发展历程,展望了新世纪的医学分子生物学,分子生物学的理论和技术进步改变了医学研究的格局和观念,使人们对疾病的认识深入到分子水平,分子病,基因病,构象病和信息病等概念继续被提出。医学分子生物学的未来发展必将更紧密地与其它学科如细胞生物学,发育生物学,神经生物学,理论医学等相结合,实现分子水平,细胞水平和整体水平的整合,创造更加辉煌的成就。     

Robust nonorthogonal analyses revisited: An update based on trimmed means

Three approaches to the analysis of main and interaction effect hypotheses in nonorthogonal designs were compared in a 2×2 design for data that was neither normal in form nor equal in variance. The approaches involved either least squares or robust estimators of central tendency and variability and/or a test statistic that either pools or does not pool sources of variance. Specifically, we compared the ANOVA F test which used trimmed means and Winsorized variances, the Welch-James test with the usual least squares estimators for central tendency and variability and the Welch-James test using trimmed means and Winsorized variances. As hypothesized, we found that the latter approach provided excellent Type I error control, whereas the former two did not.Financial support for this research was provided by grants to the first author from the National Sciences and Engineering Research Council of Canada (#OGP0015855) and the Social Sciences and Humanities Research Council (#410-95-0006). The authors would like to express their appreciation to the Associate Editor as well as the reviewers who provided valuable comments on an earlier version of this paper.