Gaze differences in configural and elemental evaluation during multi-attribute decision-making

Introduction

While many everyday choices are between multi-attribute options, how attribute values are integrated to allow such choices remains unclear. Recent findings suggest a distinction between elemental (attribute-by-attribute) and configural (holistic) evaluation of multi-attribute options, with different neural substrates. Here, we asked if there are behavioral or gaze pattern differences between these putatively distinct modes of multi-attribute decision-making.

Methods

Thirty-nine healthy men and women learned the monetary values of novel multi-attribute pseudo-objects (fribbles) and then made choices between pairs of these objects while eye movements were tracked. Value was associated with individual attributes in the elemental condition, and with unique combinations of attributes in the configural condition. Choice, reaction time, gaze fixation time on options and individual attributes, and within- and between-option gaze transitions were recorded.

Results

There were systematic behavioral differences between elemental and configural conditions. Elemental trials had longer reaction times and more between-option transitions, while configural trials had more within-option transitions. The effect of last fixation on choice was more pronounced in the configural condition.

Discussion

We observed differences in gaze patterns and the influence of last fixation location on choice in multi-attribute value-based choices depending on how value is associated with those attributes. This adds support for the claim that multi-attribute option values may emerge either elementally or holistically, reminiscent of similar distinctions in multi-attribute object recognition. This may be important to consider in neuroeconomics research that involve visually-presented complex objects.

Remember This: Age Moderation of Genetic and Environmental Contributions to Verbal Episodic Memory from Midlife through Late Adulthood

It is well documented that memory is heritable and that older adults tend to have poorer memory performance than younger adults. However, whether the magnitudes of genetic and environmental contributions to late-life verbal episodic memory ability differ from those at earlier ages remains unresolved. Twins from 12 studies participating in the Interplay of Genes and Environment in Multiple Studies (IGEMS) consortium constituted the analytic sample. Verbal episodic memory was assessed with immediate word list recall (N = 35,204 individuals; 21,792 twin pairs) and prose recall (N = 3,805 individuals; 2,028 twin pairs), with scores harmonized across studies. Average test performance was lower in successively older age groups for both measures. Twin models found significant age moderation for both measures, with total inter-individual variance increasing significantly with age, although it was not possible definitively to attribute the increase specifically to either genetic or environmental sources. Pooled results across all 12 studies were compared to results where we successively dropped each study (leave-one-out) to assure results were not due to an outlier. We conclude the models indicated an overall increase in variance for verbal episodic memory that was driven by a combination of increases in the genetic and nonshared environmental parameters that were not independently statistically significant. In contrast to reported results for other cognitive domains, differences in environmental exposures are comparatively important for verbal episodic memory, especially word list learning.

Disruption of individual members of Arabidopsis syntaxin gene families indicates each has essential functions

Syntaxins are a large group of proteins found in all eukaryotes involved in the fusion of transport vesicles to target membranes. Twenty-four syntaxins grouped into 10 gene families are found in the model plant Arabidopsis thaliana, each group containing one to five paralogous members. The Arabidopsis SYP2 and SYP4 gene families contain three members each that share 60 to 80% protein sequence identity. Gene disruptions of the yeast (Saccharomyces cerevisiae) orthologs of the SYP2 and SYP4 gene families (Pep12p and Tlg2p, respectively) indicate that these syntaxins are not essential for growth in yeast. However, we have isolated and characterized gene disruptions in two genes from each family, finding that disruption of individual syntaxins from these families is lethal in the male gametophyte of Arabidopsis. Complementation of the syp21-1 gene disruption with its cognate transgene indicated that the lethality is linked to the loss of the single syntaxin gene. Thus, it is clear that each syntaxin in the SYP2 and SYP4 families serves an essential nonredundant function.

Arabidopsis transcription factors: genome-wide comparative analysis among eukaryotes

The completion of the Arabidopsis thaliana genome sequence allows a comparative analysis of transcriptional regulators across the three eukaryotic kingdoms. Arabidopsis dedicates over 5% of its genome to code for more than 1500 transcription factors, about 45% of which are from families specific to plants. Arabidopsis transcription factors that belong to families common to all eukaryotes do not share significant similarity with those of the other kingdoms beyond the conserved DNA binding domains, many of which have been arranged in combinations specific to each lineage. The genome-wide comparison reveals the evolutionary generation of diversity in the regulation of transcription.

Electron-microscopic findings after transmyocardial laser revascularization in an acute ischemic pig model

OBJECTIVE

The clinical benefit in terms of angina reduction after transmyocardial laser revascularization (TMLR) in patients with diffuse coronary artery disease who are not candidates for conventional procedures has been proved. The exact mechanisms of TMLR however, are still unknown. The aim of this study was to investigate the cellular changes in relation to intramyocardial partial oxygen pressure (ptiO2) after TMLR in a model of acute ischemia in pigs by electron microscopical methods (TEM).

METHODS

Seven pigs were included in this study (five animals with acute myocardial ischemia and additional TMLR and two animals with acute myocardial ischemia and without TMLR for control). Acute ischemia was induced by ligation of diagonal branches of the left anterior descending artery (LAD). Intramyocardial partial oxygen pressure was measured before induction of ischemia and thereafter continuously for up to 6 h in all animals. Biopsies of all animals were taken before induction of ischemia and thereafter at 30 min, 3 and 6 h. Analysis of the myocardial ultrastructure was focused on mitochondria, cell nucleus, T-tubules and myofibrils.

RESULTS

Ultrastructural changes were seen in all animals. At 6 h after induction of ischemia, mitochondria showed a destruction of the internal as well as the external membrane and of the cristae. The nuclei showed margination of the chromatin. Myofibrils were characterized by ruptures in the Z-stripes. Lipid droplets as an indicator of ischemia could be identified. PtiO2 between 40 and 80 mmHg before intervention decreased down to 0-2 mmHg within the first 9 min after diagonal branch ligation and did not increase even after TMLR.

CONCLUSIONS

In this acute ischemic model using pigs, TEM evaluation following TMLR proves irreversible changes of the myocardial ultrastructure. Furthermore, TMLR was not able to increase ischemically induced decrease of ptiO2. These data provide some evidence that TMLR thus, may not be able to ameliorate acute ischemia at least in the pig model. Further investigations are needed to investigate the effect of TMLR in chronic myocardial ischemia.

Media influence on attitudes toward suicide

This experiment investigated the effects of viewing films on suicide and violence on attitudes toward suicide. Non-suicidal university students were assigned to one of three groups: One group was shown a film about suicide, a second saw a film about violence, and the third saw a neutral film. Perceptions of the appropriateness of suicide and level of emotional arousal were measured by a questionnaire administered before and after the films were shown. Both the suicide and violent film groups showed increases in arousal scores after viewing the films. The results suggest that arousal became linked to cognitions specific to film content as a result of viewing the films dealing with suicide and violence. Other findings suggest that, for the suicide and violent film groups, perceived relations with parents were important predictors of film-induced changes in attitudes toward suicide.

[Spontaneous manifestation and regression of a Kaposi's sarcoma under cyclosporin A therapy]

A case of Kaposi sarcoma is reported in a 40-year-old Turk 3 months after a kidney transplantation under immunosuppression with cyclosporin A and methylprednisolone. After reduction of immunosuppression, there was complete regression of the sarcoma and the kidney transplant functioned correctly.