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PubMed1987

Logical memory subtest of the Wechsler Memory Scale: age and education norms and alternate-form reliability of two scoring systems.

The Logical Memory (LM) subtest of the Wechsler Memory Scale has been characterized by imprecise scoring instructions which can make data interpretation and study comparisons difficult. A total of 339 adults, from 18 to 83 years old, took either Form I or Form II of the LM. Verbal recall of the story passages was evaluated using gist and verbatim scoring systems. Interrater reliability was very high for both scoring approaches. The two forms were equivalent for gist recall. However, verbatim recall of Form I was more difficult than Form II because the former consists of more words to remember. Recall was related more to educational level than to age. For both gist and verbatim scoring, age and education norms were generated for immediate, delayed, and 24-h recall.

Adolescent↗

PubMed1992

A scoring method for logical memory that is sensitive to right-hemispheric dysfunction.

We developed a relationally processing-based scoring system (RPSS) for the Wechsler Memory Scale's (WMS) Logical Memory subtest. Information from the stories was classified as either essential to the plot (Essential proposition) or nonessential to the plot (Detail proposition). The subjects' responses were also scored for intrusion errors (Self-Generated propositions). The normal control group's performance was compared with the performance of a right cerebrovascular accident group (R-CVA), and a left cerebrovascular accident group (L-CVA), each consisting of 20 right-handed subjects. ANOVAs revealed that the R-CVA group recalled significantly fewer Detail propositions and produced significantly more Self-Generated propositions than did the Normal Control group. In contrast, these groups recalled approximately the same number of Essential propositions. The L-CVA group recalled fewer Essential propositions than did any other group, but also produced the fewest intrusion errors.

Arousal↗

PubMed1993

The diagnostic utility of savings scores: differentiating Alzheimer's and Huntington's diseases with the logical memory and visual reproduction tests.

Recent research has demonstrated that patients with dementia of the Alzheimer type (DAT) evidence more rapid forgetting than do patients with Huntington's disease (HD). The present study focused on whether such group differences translated into measures with adequate sensitivity and specificity at different stages of these disorders. It was found that measures of forgetting (i.e., savings scores) based upon the Logical Memory and Visual Reproduction tests of the Wechsler Memory Scale--Revised had satisfactory to excellent sensitivity and specificity in differentiating DAT and HD patients from healthy control subjects. Savings scores also had good sensitivity and specificity in differentiating DAT from HD in the early stages of the diseases. However, unsatisfactory specificity may limit the utility of savings scores in differentiating among patients with moderate DAT and HD.

Aged↗

PubMed2004

Qualitative analysis of WMS-III Logical Memory and Visual Reproduction in temporal lobe epilepsy.

Clinical observation of performance on the Logical Memory (LM) and Visual Reproduction (VR) subtests from the WMS-III has revealed some variability in retention rates across stories and figures. This paper examined the degree to which this variability occurs in lateralized temporal lobe epilepsy (TLE) in comparison to a matched group from the WMS-III standardization sample, and explored whether analysis of qualitative aspects of LM and VR performance yield additional lateralizing information in TLE. Analysis of LM and VR scaled scores revealed differences between the TLE groups for LM, but not VR scores. All subjects benefited from repetition of LM Story B, with greater improvement in story retention in the Left versus Right TLE group. Variability in VR recall across figures was seen in all groups, with a bimodal distribution of retention rates for each figure and a sizable percentage of each group completely forgetting two or more figures. These results suggest that more careful analysis of individual LM story performance may be useful in some patients with TLE, whereas variability in VR retention across figures is common and should not be over interpreted.

Adult↗

PubMed2004

Age-associated memory impairment of Logical Memory and Visual Reproduction.

The standardization sample from the WMS-III (weighted N = 1250) (The Psychological Corporation, 1997; Tulsky & Ledbetter, 2000), which varied in age from 16 to 89, was used to determine whether storage of verbal and spatial information was affected by normal aging. A previous study with the same sample using an analysis of variance approach showed that the age-associated deterioration for Logical Memory (LM) and Visual Reproduction (VR) delayed recall and recognition were comparable and largely explained by poor immediate recall. This led to the conclusion that age-associated memory impairment was due primarily to encoding deficits. However, that study did not control for the age-associated deterioration in immediate recall in order to ensure that the small age-associated effects for delayed recall and recognition were not confounded by the fact that the elderly had less to remember on the delayed recall and recognition trials. The current study used covariance analysis to statistically adjust the dependent measures, LM and VR delayed recall and recognition, based on immediate recall scores. These analyses showed that the age-associated changes in these measures were statistically significant, but the effect sizes were very small. Partial eta(2) for the main effect of age for LM was 0.06 with weak effect sizes for the interaction of recall type and age (0.02). The partial eta(2) for the main effect of age for VR was 0.09, and the interaction of recall type and age (0.04). This pattern of findings shows that after adjustment for immediate recall, LM and VR recall and recognition demonstrated comparable, slight declines with age suggesting that normal aging produced minimal changes in the ability to store new information when age-associated changes in initial encoding and retrieval were statistically controlled.

Adolescent↗

PubMed2006

WMS-III Logical Memory performance after a two-week delay in temporal lobe epilepsy and control groups.

Conventional memory assessment may fail to identify memory dysfunction that is characterized by intact recall for a relatively brief period but rapid forgetting thereafter. This study assessed immediate memory and retention after 30-minute and two-week delays in a control group (n = 25) and a group of individuals with temporal lobe epilepsy (TLE, n = 25). For raw free recall, thematic unit, and recognition memory scores from the Wechsler Memory Scale-3rd ed. (WMS-III) Logical Memory (LM) subtest, there were no group x trial interactions and the TLE group performed significantly worse than the controls on all trials. At the individual level, none of the patients (0%) demonstrated isolated free recall impairment at the two-week delay when raw scores were analyzed, and one patient (4%) but also five controls (20%) did so when percent retention scores were examined. In summary, TLE patients did not demonstrate disproportionate forgetting over two weeks on a widely used story memory test.

Adult↗

PubMed2006

Logic for designing nature reserves for multiple species.

We examine the logic of designing nature reserves to understand better how to integrate the concepts of representativeness and persistence. Simple models of viability are used to evaluate how the expected number of species in the reserve system changes with variation in the risk of extinction among species, their rate of occurrence, and the distribution of species. The optimal size of individual reserves increased with the mean and variance of the probability of extinction among species and with the rate at which the risk of extinction declines with the cost of each reserve. In contrast, the rate of occurrence of species within reserves and their rate of accumulation with increasing reserve area had a relatively minor influence on the optimal size of reserves. Patterns of endemism were most important for the location of reserves. Including differences among species in the analysis reduced the optimal number of individual reserves (and increased the size of each) when operating under a fixed budget compared with reserve designs based on single species. A case study in the city of Melbourne, Australia, demonstrates the conservation value of small (approximately 1 ha) grassland reserves and the underrepresentation of Melbourne's volcanic plains in the region's conservation network.

Computer Simulation↗

PubMed2002

Ethical, logical and scientific problems with the new ICRP proposals.

Last year the ICRP proposed a new system of radiation protection designed to be simpler, more oriented toward individual protection and reflective of important ethical standards. This article argues that the proposal violates important norms of scientific simplicity, is in fact less protective of individuals than the current system and makes a number of ethical errors. After outlining 12 ethical errors, five logical errors and two scientific problems with the new ICRP proposal, the present authors suggest possible ways to remedy these deficiencies.

Ethical Analysis↗

PubMed2006

Regulating biorisks: Developing a coherent policy logic (part I).

This is the first of two articles empirically detailing the working practices of regulators who are charged with overseeing biological research. Specifically, it considers how regulators from the Biological Agents Unit of the UK Health and Safety Executive review notifications and applications, carry out inspections of research centres, and enforce the law once breaches are uncovered. This first article focuses on the Unit's working practices before 9/11, and the second, forthcoming article focuses on the Unit's working practices after 9/11. I argue that an understanding of the implementation processes--that is, the strategies adopted by regulatory agencies and the styles employed by agency regulators in their interactions with those regulated--is critical to developing a coherent policy logic for the developing regulatory regime around biorisks.

Academies and Institutes↗

PubMed2006

Logic regression for analysis of the association between genetic variation in the renin-angiotensin system and myocardial infarction or stroke.

Recent developments in genetic sequencing technology now make it possible to genotype large numbers of single nucleotide polymorphisms (SNPs) in large samples. Many association studies using SNP data are now being carried out. Typically, these observational studies establish whether certain haplotypes or individual SNPs are associated with a health outcome. Few methods exist for finding interaction effects among multiple SNPs or between SNPs and environmental factors. In this paper, the authors describe logic regression, an exploratory method with which to identify interactions for further research. They illustrate this method using data from a US case-control study of myocardial infarction and stroke (1995-1999) carried out among 1,614 persons in Washington State who were genotyped for 32 SNPs on five genes in the renin-angiotensin system.

Angiotensins↗

PubMed1985

ACNUC--a portable retrieval system for nucleic acid sequence databases: logical and physical designs and usage.

ACNUC is a database structure and retrieval software for use with either the GenBank or EMBL nucleic acid sequence data collections. The nucleotide and textual data furnished by both collections are each restructured into a database that allows sequence retrieval on a multi-criterion basis. The main selection criteria are: species (or higher order taxon), keyword, reference, journal, author, and organelle; all logical combinations of these criteria can be used. Direct access to sequence regions that code for a specific product (protein, tRNA or rRNA) is provided. A versatile extraction procedure copies selected sequences, or fragments of them, from the database to user files suitable to be analysed by user-supplied application programs. A detailed help mechanism is provided to aid the user at any time during the retrieval session. All software has been written in FORTRAN 77 which guarantees a high degree of transportability to minicomputers or mainframes.

Base Sequence↗

PubMedDate not supplied

Genetic control of flower morphogenesis in Arabidopsis thaliana: a logical analysis.

MOTIVATION: A large number of molecular mechanisms at the basis of gene regulation have been described during the last few decades. It is now becoming possible to address questions dealing with both the structure and the dynamics of genetic regulatory networks, at least in the case of some of the best-characterized organisms. Most recent attempts to address these questions deal with microbial or animal model systems. In contrast, we analyze here a gene network involved in the control of the morphogenesis of flowers in a model plant, Arabidopsis thaliana. RESULTS: The genetic control of flower morphogenesis in Arabidopsis involves a large number of genes, of which 10 are considered here. The network topology has been derived from published genetic and molecular data, mainly relying on mRNA expression patterns under wild-type and mutant backgrounds. Using a 'generalized logical formalism', we provide a qualitative model and derive the parameter constraints accounting for the different patterns of gene expression found in the four floral organs of Arabidopsis (sepals, petals, stamens and carpels), plus a 'non-floral' state. This model also allows the simulation or the prediction of various mutant phenotypes. On the basis of our model analysis, we predict the existence of a sixth stable pattern of gene expression, yet to be characterized experimentally. Moreover, our dynamical analysis leads to the prediction of at least one more regulator of the gene LFY, likely to be involved in the transition from the non-flowering state to the flowering pathways. Finally, this work, together with other theoretical and experimental considerations, leads us to propose some general conclusions about the structure of gene networks controlling development.

Arabidopsis↗

PubMed2025

Privacy-hardened and hallucination-resistant synthetic data generation with logic-solvers.

MOTIVATION: Machine-generated or synthetic data is a valuable resource for training artificial intelligence algorithms, evaluating rare workflows, and sharing data under stricter data legislations. However, current statistical and deep learning methods struggle with large data volumes, are prone to hallucinating scenarios incompatible with reality, and seldom quantify privacy meaningfully. RESULTS: Here, we introduce Genomator, a logic solving approach (SAT solving), which efficiently produces private and realistic representations of the original data. We demonstrate the method on genomic data, which arguably is the most complex and private information. We benchmark Genomator against state-of-the-art methodologies (Markov generation, Wasserstein Generative Adversarial Network and Conditional Restricted Boltzmann Machines), demonstrating a 40%-530% accuracy improvement and 57%-172% higher privacy. Genomator is also 3-100 times more efficient, making it the only tested method that scales to whole genomes. We show the universal trade-off between privacy and accuracy, and use Genomator's tuning capability to cater to all applications along the spectrum, from provable private representations of sensitive cohorts, to datasets with indistinguishable pharmacogenomic profiles. Demonstrating the production-scale generation of tuneable synthetic genomes hold great potential for balancing underrepresented populations in medical research and advancing global data exchange. AVAILABILITY AND IMPLEMENTATION: Genomator is available at https://github.com/csiro/genomator.

Algorithms↗

PubMed2005

Inferring genetic regulatory logic from expression data.

MOTIVATION: High-throughput molecular genetics methods allow the collection of data about the expression of genes at different time points and under different conditions. The challenge is to infer gene regulatory interactions from these data and to get an insight into the mechanisms of genetic regulation. RESULTS: We propose a model for genetic regulatory interactions, which has a biologically motivated Boolean logic semantics, but is of a probabilistic nature, and is hence able to confront noisy biological processes and data. We propose a method for learning the model from data based on the Bayesian approach and utilizing Gibbs sampling. We tested our method with previously published data of the Saccharomyces cerevisiae cell cycle and found relations between genes consistent with biological knowledge.

Bayes Theorem↗

PubMed2006

Dynamics of prefrontal and cingulate activity during a reward-based logical deduction task.

We used behavioral and functional magnetic resonance imaging (fMRI) methods to probe the cerebral organization of a simple logical deduction process. Subjects were engaged in a motor trial-and-error learning task, in which they had to infer the identity of an unknown 4-key code. The design of the task allowed subjects to base their inferences not only on the feedback they received but also on the internal deductions that it afforded (autoevaluation). fMRI analysis revealed a large bilateral parietal, prefrontal, cingulate, and striatal network that activated suddenly during search periods and collapsed during ensuing periods of sequence repetition. Fine-grained analyses of the temporal dynamics of this search network indicated that it operates according to near-optimal rules that include 1) computation of the difference between expected and obtained rewards and 2) anticipatory deductions that predate the actual reception of positive reward. In summary, the dynamics of effortful mental deduction can be tracked with fMRI and relate to a distributed network engaging prefrontal cortex and its interconnected cortical and subcortical regions.

Adult↗

PubMed2001

The molecular logic of olfaction in Drosophila.

Drosophila fruit flies display robust olfactory-driven behaviors with an olfactory system far simpler than that of vertebrates. Endowed with 1300 olfactory receptor neurons, these insects are able to recognize and discriminate between a large number of distinct odorants. Candidate odorant receptor molecules were identified by complimentary approaches of differential cloning and genome analysis. The Drosophila odorant receptor (DOR) genes encode a novel family of proteins with seven predicted membrane-spanning domains, unrelated to vertebrate or nematode chemosensory receptors. There are on the order of 60 or more members of this gene family in the Drosophila genome, far fewer than the hundreds to thousands of receptors found in vertebrates or nematodes. DOR genes are selectively expressed in small subsets of olfactory neurons, in expression domains that are spatially conserved between individuals, bilaterally symmetric and not sexually dimorphic. Double in situ RNA hybridization with a number of pairwise combinations of DOR genes fails to reveal any overlap in gene expression, suggesting that each olfactory neuron expresses one or a small number of receptor genes and is therefore functionally distinct. How is activation of such a subpopulation of olfactory receptor neurons in the periphery sensed by the brain? In the mouse, all neurons expressing a given receptor project with precision to two of 1800 olfactory bulb glomeruli, creating a spatial map of odor quality in the brain. We have employed DOR promoter transgenes that recapitulate expression of endogenous receptor to visualize the projections of individual populations of receptor neurons to subsets of the 43 glomeruli in the Drosophila antennal lobe. The results suggest functional conservation in the logic of olfactory discrimination from insects to mammals.

Animals↗

PubMed2006

Development of molecular logic gates using the structural switch of telomere DNAs.

Telomere DNAs consisting of double-stranded G-rich and C-rich sequences are particularly promising as scaffolds for molecular devices because they form high-ordered structures and have a highly polymorphic nature depending on surrounding factors. Based on the structural polymorphism of telomere DNAs, excellent molecular devices such as molecular motors and switches have been reported. Here we found that the dynamic structural conversion of telomere DNAs can be controlled by both monovalent cations (M(+)) and pH (H(+)). Based on this conversion, we propose a new concept of molecular logic gates in response to the surrounding conditions (M(+) and H(+)) with fluorescence intensity changes as the output signal.

Cations, Monovalent↗

PubMed1991

Does epidemiology need a new philosophy? A case study of logical inquiry in the acquired immunodeficiency syndrome epidemic.

The proposals of Popperian epidemiologists are examined using acquired immunodeficiency syndrome (AIDS) research as a case study. Hypothesis generation is shown to be mostly an inductive process in the case of AIDS. For hypothesis testing, researchers again preferred inductive verification over deductive falsification. Action-oriented disciplines, such as medicine and epidemiology, search for common sense certainty and not logical uncertainty. Insistence on falsification is often counterproductive. Induction and deduction, however, are not mutually exclusive. Conventional scientific methods, using both induction and deduction, appear to perform well in elucidating this latest epidemic, and Popper's philosophy has little to offer epidemiologists and other medical researchers.

Acquired Immunodeficiency Syndrome↗