Unitary Variables Research Articles

A model of bi-directional interactions between complementary learning systems for memory consolidation of sequential experiences.

The standard theory of memory consolidation posits a dual-store memory system: a fast-learning fast-decaying hippocampus that transfers memories to slow-learning long-term cortical storage. Hippocampal lesions interrupt this transfer, so recent memories are more likely to be lost than more remote memories. Existing models of memory consolidation that simulate this temporally graded retrograde amnesia operate only on static patterns or unitary variables as memories and study only one-way interaction from the hippocampus to the cortex. However, the mechanisms underlying the consolidation of episodes, which are sequential in nature and comprise multiple events, are not well-understood. The representation of learning for sequential experiences in the cortical-hippocampal network as a self-consistent dynamical system is not sufficiently addressed in prior models. Further, there is evidence for a bi-directional interaction between the two memory systems during offline periods, whereby the reactivation of waking neural patterns originating in the cortex triggers time-compressed sequential replays in the hippocampus, which in turn drive the consolidation of the pertinent sequence in the cortex. We have developed a computational model of memory encoding, consolidation, and recall for storing temporal sequences that explores the dynamics of this bi-directional interaction and time-compressed replays in four simulation experiments, providing novel insights into whether hippocampal learning needs to be suppressed for stable memory consolidation and into how new and old memories compete for limited replay opportunities during offline periods. The salience of experienced events, based on factors such as recency and frequency of use, is shown to have considerable impact on memory consolidation because it biases the relative probability that a particular event will be cued in the cortex during offline periods. In the presence of hippocampal learning during sleep, our model predicts that the fast-forgetting hippocampus can continually refresh the memory traces of a given episodic sequence if there are no competing experiences to be replayed.

Foreign to whom? Constraining the moral foreign language effect on bilinguals’ language experience

AbstractThe moral foreign language effect (MFLE) describes how people’s decisions may change when a moral dilemma is presented in either their native (NL) or foreign language (FL). Growing attention is being directed to unpacking what aspects of bilingualism may influence the MFLE, though with mixed or inconclusive results. The current study aims to bridge this gap by adopting a conceptualization of bilingualism that frames this construct as a composite and continuous measure. In a between-group analysis, we asked 196 Italian–English bilinguals to perform a moral dilemmas task in either their NL (i.e., Italian) or FL (i.e., English). In a within-group analysis, we evaluated the effects of FL age of acquisition, FL proficiency, and language dominance – all measured as continuous variables – on moral decision-making. Overall, findings indicate that differences within bilinguals’ language experience impact moral decisions in an FL. However, the effect of the linguistic factors considered was not ubiquitous across dilemmas, and not always emerged into a MFLE. In light of these results, our study addresses the importance of treating bilingualism as multidimensional, rather than a unitary variable. It also discusses the need to reconceptualize the FLE and its implications on moral decision-making.

Dyadic development in the family: Stability in mother-child relationship quality from infancy to adolescence.

A central concern of family psychology and developmental science is assessing the stability or instability (i.e., relative standing) of family-level constructs across time. Almost exclusively, such constructs have heretofore been unitary variables. Using a longitudinal design, for the first time, this study traces the developmental stability of the dyadic construct of mother-child relationship quality from infancy to adolescence. Multiple age-appropriate measures converging on the construct of relationship quality were assessed in 375 mother-child dyads at 4 times: 5 months and 4, 10, and 14 years. Mother-child relationship quality showed stability (βs = .18-.53) in all families together, in families with girls and boys, and when family socioeconomic status was controlled. Consistent patterns of relationship quality are developmentally significant in themselves, convert to broader behavioral tendencies in children, and guide more effective intervention designs. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Moral Judgement in Early Bilinguals: Language Dominance Influences Responses to Moral Dilemmas.

The Foreign-Language effect (FLe) on morality describes how late bilinguals make different decisions on moral judgements, when presented in either their native or foreign language. However the relevance of this phenomenon to early bilinguals, where a language's “nativeness” is less distinct, is unknown. This study aims to verify the effect of early bilinguals' languages on their moral decisions and examine how language experience may influence these decisions. Eighty-six early English-Chinese bilinguals were asked to perform a moral dilemmas task consisting of personal and impersonal dilemmas, in either English or Mandarin Chinese. Information on language experience factors were also collected from the participants. Findings suggest that early bilinguals do show evidence of a language effect on their moral decisions, which is dependent on how dominant they are in the language. Particularly, the more dominant participants were in their tested language, the larger the difference between their personal and impersonal dilemma response choice. In light of these findings, the study discusses the need to re-examine how we conceptualize the FLe phenomenon and its implications on bilinguals' moral judgement. It also addresses the importance of treating bilingualism as multidimensional, rather than a unitary variable.

A unified method for the response analysis of interval/random variable models of acoustic fields with uncertain‐but‐bounded parameters

SummaryFor the response analysis of engineering systems with uncertain‐but‐bounded parameters, three uncertain models have been considered according to the available probability distribution information. One is the bounded random model in which the uncertain parameters are well defined with sufficient probability distribution information and described as bounded random variables. The second one is the interval model in which the uncertain parameters are expressed as interval variables without giving any information of probability distribution. The last one is the bounded hybrid uncertain model, which includes both bounded random variables and interval variables. On the basis of Gegenbauer polynomial approximation theory, a unified interval and random Gegenbauer series expansion (IRGSE) method is proposed and extended for the response prediction of three uncertain models of acoustic fields with uncertain‐but‐bounded parameters. In IRGSE, the uncertain‐but‐bounded variables with different probability distribution information, including interval variables and bounded random variables with different probability density functions, are transformed into the function of unitary variables defined on [‐1,1] associated with the corresponding polynomial parameter (λ) of Gegenbauer series expansion (GSE). The coefficients of GSE is calculated by Gauss–Gegenbauer integration method. By using IRGSE, the responses of three uncertain acoustic models are approximated uniformly by GSE, through which the interval and random analysis can be easily implemented by many numerical solvers. Two numerical examples are applied to investigate the effectiveness of the proposed method. Copyright © 2016 John Wiley & Sons, Ltd.

⁎-freeness in finite tensor products

In this paper, we consider the following question and variants thereof: given D:=(a1;i⊗⋯⊗aK;i:i∈I), a collection of elementary tensor non-commutative random variables in the tensor product of probability spaces (A1⊗⋯⊗AK,φ1⊗⋯⊗φK), when is D ⁎-free? (See Section 1.2 for a precise formulation of this problem.)Settling whether or not freeness occurs in tensor products is a recurring problem in operator algebras, and the following two examples provide a natural motivation for the above question:(A)If (a1;i:i∈I) is a ⁎-free family of Haar unitary variables and ak,i are arbitrary unitary variables for k≥2, then the ⁎-freeness persists at the level of the tensor product D.(B)A converse of (A) holds true if all variables ak;i are group-like elements (see Corollary 1.7 of Proposition 1.6).It is therefore natural to seek to understand the extent to which such simple characterizations hold true in more general cases. While our results fall short of a complete characterization, we make notable steps toward identifying necessary and sufficient conditions for the freeness of D. For example, we show that under evident assumptions, if more than one family (ak,i:i∈I) contains non-unitary variables, then the tensor family fails to be ⁎-free (see Theorem 1.8 (1)).

So, Talk to Me: The Effect of Explicit Goals on the Comprehension of Business Process Narratives

Unstructured data, most of it text-based and computer- mediated, makes up a rapidly growing majority of the knowledge store of most organizations. Entire classes of information systems-knowledge management systems and enterprise content management systems-have emerged to monitor, manage, and support decision making from this primarily textual data. IS research has treated text as a unitary variable. However, research from cognitive science strongly suggests that a deeper investigation of how text is comprehended would allow the development of more effective computer-based knowledge and communications systems. Our research extends IS research on the effects of information presentation on decision making by investigating the attributes of text rather than comparing text to other information presentation modes such as graphs or numbers. Our study also contributes to the sparse empirical IS research on problem formulation, the initial phase of decision making. Informed by research on information presentation, decision making, and narrative comprehension, we designed a series of experiments that demonstrate that the explicit inclusion of goal information for activities in narrative descriptions of problematic business processes increases overall comprehension, decision-making confidence, and short and long term recall. Based on our experimental findings we propose that augmenting text-based IS to elicit and saliently present explicit goal information would significantly enhance the decision support capability of these systems especially for rapid, ad hoc decisions about business process situations.

The localizing value of ictal consciousness and its constituent functions: a video-EEG study in patients with focal epilepsy.

Using ictal neuropsychological testing in pre-surgical patients with focal epilepsies, we examined the localizing value of the constituent functions of consciousness as opposed to 'conscious behaviour' as a unitary variable. 'Conscious behaviour' was defined in terms of awareness and responsiveness. The constituent functions of consciousness examined included the orientation to the examiner, intentional behaviour demonstrated by expressive or receptive speech, and postictal memory. Frequency and patterns of impairment of constituent functions and 'conscious behaviour' were assessed. To achieve this, pre-surgical video-EEG (n = 40) or video-electrocorticography recordings (n = 76) of ictal neuropsychological assessments were reviewed retrospectively. Patients were divided into groups with frontal (n = 29), right temporal (n = 21), left temporal (n = 38) and bitemporal (n = 28) seizure activity. Consciousness was most commonly impaired in patients with bitemporal and left temporal seizure activity. There were different patterns of impairment of the assessed constituent functions in the four groups: patients with frontal seizure activity showed loss of orientation behaviour and expressive speech whereas patients with left temporal seizure activity had impairments of memory, expressive and receptive speech. Patients with seizure activity limited to the right temporal lobe rarely exhibited ictal impairment of any of the assessed functions. In contrast, patients with bitemporal seizure activity showed impairment of all examined functions. Hence, normal functioning of the left temporal lobe or both temporal lobes is necessary for the preservation of all constituent aspects of consciousness. The localizing value of patterns of impairment of constituent functions is superior to that of 'consciousness' as a whole.

Cohesiveness and Performance on an Additive Task: Evidence for Multidimensionality

Abstract This experiment contrasted two predictions regarding the effects of two types of cohesiveness on the performance of American students. Task-based cohesion and interpersonal cohesion were manipulated independently. Results show that high task cohesion facilitated performance, whereas interpersonal attraction had no apparent effect on production. Increases in interpersonal cohesion did, however, result in higher task commitment and more frequent interactions among group members. A path analysis suggested that potentially beneficial effects on production of increasing task commitment were obviated by the increased conversation also resulting from interpersonal cohesion. These data suggest that cohesiveness should be conceptualized as a multidimensional rather than as a unitary variable.

The Effects of Task and Interpersonal Cohesiveness on Performance of a Disjunctive Group Task1

This experiment examined the effects of two different types of group cohesiveness on performance of a disjunctive task. Both interpersonal and task cohesiveness were varied independently. Results show that high levels of both types of cohesiveness were necessary for success on a task requiring group interaction. Groups high on one type of cohesiveness but low on another performed no better than groups low on both types of cohesiveness. These results suggest that cohesiveness should be conceptualized as a multidimensional rather than as a unitary variable. It is also suggested that the effects noted in the present study may well vary according to task characteristics.

Active avoidance performance in genetically defined mice

It has been concluded by several investigators that active avoidance performance in mice is primarily influenced or even determined by a single gene. The genetically defined strains C57BL/6 and BALB/c have provided evidence that an aberrant development of pyramidal cells and mossy fiber configuration in the hippocampus of BALB/c mice also is determined by a single gene. As a test of the generality of the single gene influence on avoidance learning, and to examine the relationship of the hippocampal defect to avoidance learning, adult male mice of the inbred progenitor strains C57BL/6ByJ and BALB/cByJ and their seven recombinant inbred strains were tested in a variant of the shuttle-box paradigm used in previous studies. BALB/c were found to acquire the avoidance response at a faster rate than C57BL/6, consistent with most earlier reports, but performances of the recombinant inbred strains failed to dichotomize about the progenitor strains. The rank order of performance scores for the recombinant inbred strains was different from that reported in previous studies. Thus the present data failed to support the interpretation of a single major gene influencing active avoidance learning. It is concluded that avoidance learning and performance cannot be considered as unitary variables and that the interaction of genetic with environmental factors, including the conditions of the specific testing situation, are important considerations in any interpretation of genetic effects. No relationship between the hippocampal lamination defect and avoidance performance was demonstrated.

Ego Development and Conformity: A Construct Validity Study of the Washington University Sentence Completion Test

Loevinger's conception of ego development predicts a curvilinear relation between it and conformity. Using 107 private-school boys in grades 8, 9, and 11, self-report, peer-nomination, and experimental (Willis) measures of conformity were given. An archival measure, number of demerits, was also obtained. As predicted, the self-report and archival measures show maximum conformity between the Self-Protective and Conscientious Stages as measured by the sentence completion test. These results are not artifacts of age or IQ. The Willis test does not correlates significantly any other variable, and the peer ratings were methodologically suspect. Thus one aspect of the conception of ego development is partially confirmed. Conformity. as measured by these typical tests, is shown not to be a unitary variable.

Homicide Victims and Offenders: An Israeli Study

Although criminal homicide has been the subject of numerous investigations, the number of empirical studies is limited.' The basic methodological assumption underlying this article is that the act of homicide cannot be explained by any simple, broad, unitary variable. Rather, it must be viewed as the consequence of involvement with and interaction of a variety of variables. The purpose of this study is to identify these variables and to assess the relative contribution of each to the resultant act of criminal homicide.

Linguistic Units and Speech Production Theory

Today, one seldom hears of the unit of speech production. Speech error data, in particular, have made it clear that every linguistic unit from “phonemic phrase” through “word,” “morpheme,” “syllable,” and “phoneme” to “distinctive feature” is useful to the speech production theorist in that each allows him to conceptualize processes whereby the speaker manipulates unitary variables in his output. As some of these units must be “activated” prior to others in the organization of output, and as some units actually overlap structurally with others, we require a hierarchical model specifying the sequence of events leading to output and resolving problems of overlap. Some clues to the form of this model are available. Very little is known about the higher order units—phonemic phrase, word, morpheme—in this regard. For the lower-order units much conceptual difficulty remains, including questions asked to the physical manifestation of the syllable, and the inventory of phonemes and features. Most work in linguistic science proper has been of limited assistance here because of its virtually sole concern with contrastive properties of speech, and its failure to conceptually distinguish production from perception. Problems of sampling and interpretation may also limit further profit from speech error data. The most basic problem of speech production theory has always been that although speech must be conceptualized in terms of units, a speaker's output is a continuous strain in which movements of various articulators overlap in space and time. Studies of the dynamics of these movement sequences show promise of providing the best empirical base for theory of speech production in which linquistic units and observable physical processes are reconciled. Consideration of timing mechanisms and rhythmic organization will be a prerequisite to such a theory, and sets of rules relating citation form speech to spontaneous speech must be included. The invariants in this theory will be found in the goals being attempted rather than in the means being used to achieve them.

Proposals for Interest Test Development and Experimentation

6 proposals were suggested as a guide to interest‐experimentation and test construction. (1) An adequate theory of interests should be developed and used as a guide for experimentation and test construction. (2) Basic unitary variables should be identified. Factor analytic evidence was presented for 6 well‐established interests measured by the SVIB, KPR, and KIT. (3) Relationships of basic interest variables with other personality variables should be identified. (4) Academic achievement should be a major criterion variable. Data were presented showing significant interest correlations with college grades, interacting with test characteristics. (5) Experiments should investigate multiple variables and their interactions. (6) Only after implementation of the previous proposals should investigations consider antecedent conditions, genetic factors, and learning processes.