Visual image retention does not contribute to modulation of event-related potentials by mental rotation

Rotation of a visual image in mind is associated with a slow posterior negative deflection of the event-related potential (ERP), termed rotation-related negativity (RRN). Retention of a visual image in short-term memory is also associated with a slow posterior negative ERP, termed negative slow wave (NSW). We tested whether short-term memory retention, indexed by the NSW, contributes to the RRN. ERPs were recorded in the same subjects in two tasks, a mental rotation task, eliciting the RRN, and a visual short-term memory task, eliciting the NSW. Over both right and left parietal scalp, no association was found between the NSW and the RRN amplitudes. Furthermore, adjusting for the effect of the NSW had no influence on a significant association between the RRN amplitude and response time, an index of mental rotation performance. Our data indicate that the RRN reflects manipulation of a visual image but not its retention in short-term memory.     

Exact solution of the one-dimensional Potts bridge model with competing interactions

Abstract

The exact solution of the q-state Potts bridge model with competing ferromagnetic and antiferromagnetic interactions is obtained and corresponding regular and critical behaviour studied.     

Moderating effects of job insecurity in the relationships between procedural justice and employee well-being: Gender differences

This study tested the predictions of the uncertainty management model in explaining employee well-being. On the basis of this model we hypothesized that job insecurity would moderate the association between procedural justice (i.e., procedural and interactional justice) and well-being (i.e., emotional exhaustion and stress symptoms). Linear hierarchical regression models were used to analyse data on 1443 employees in the municipal technical sector. The findings of the study supported the hypothesis. Employees who perceived the organization as unfair and experienced job insecurity were at a higher risk of emotional exhaustion and stress symptoms. However, the results were partly gender specific.     

Can organizational justice mitigate the negative effects of shift work and fixed-term employment?

The present study examined whether organizational justice moderates the association of shift work and employment type with patient-related stress, stress symptoms, and musculoskeletal symptoms. Cross-sectional survey data from 1270 Finnish female elderly care staff aged 18–69 years was used. Analyses of covariance were used to examine the associations adjusted for age,marital status, education, and tenure. Organizational justice was associated with lower levels of patient-related stress, stress symptoms, and musculoskeletal symptoms. Organizational justice mitigated stress symptoms related to working night shift and three shifts. In addition, organizational justice mitigated the patient-related stress associated with working on fixed-term contracts. Organizational justice was also able to alleviate musculoskeletal symptoms associated with working on permanent contracts. Thus, we found evidence for organizational justice being able to mitigate the negative effects of shift work and employment type. Promoting organizational justice in organizations with shift work and lots of fixed-term contracts is of importance.     

Evidence for the integration of audiovisual emotional information at the perceptual level of processing

The present aim was to investigate how emotional expressions presented on an unattended channel affect the recognition of the attended emotional expressions. In Experiments 1 and 2, facial and vocal expressions were simultaneously presented as stimulus combinations. The emotions (happiness, anger, or emotional neutrality) expressed by the face and voice were either congruent or incongruent. Subjects were asked to attend either to the visual (Experiment 1) or auditory (Experiment 2) channel and recognise the emotional expression. The result showed that the ignored emotional expressions significantly affected the processing of attended signals as measured by recognition accuracy and response speed. In general, attended signals were recognised more accurately and faster in congruent than in incongruent combinations. In Experiment 3, possibility for a perceptual-level integration was eliminated by presenting the response-relevant and response-irrelevant signals separated in time. In this situation, emotional information presented on the nonattended channel ceased to affect the processing of emotional signals on the attended channel. The present results are interpreted to provide evidence for the view that facial and vocal emotional signals are integrated at the perceptual level of information processing and not at the later response-selection stages.     

Blood flow velocity changes in anterior cerebral arteries during cognitive tasks performance

Objective

Transcranial Doppler sonography (TCD) enables monitoring of blood flow velocities (BFVs) in basal cerebral arteries during different cognitive tasks performance with great temporal resolution. So far, BFVs changes during mental activity were monitored primarily in middle cerebral arteries (MCAs) and little is known about these changes in anterior cerebral arteries (ACAs).

Aim

To determine the effect of different cognitive tasks performance on BFV changes and hemispheric dominance in ACAs and to assess the most suitable activation test for monitoring of BFV changes in ACAs.

Methods

Fourteen right-handed, healthy subjects aged 20–26 were included in the study. BFVs in both ACAs were recorded simultaneously during performance of cognitive tasks designed to activate frontal lobes: phonemic verbal fluency test (pVFT), Stroop tests and Trail Making Tests (TMTs).

Results

A statistically significant BFV increase was recorded in both ACAs during performance of all cognitive tasks. Statistically significant right ACA dominance was found during performance of pVFT and TMTB. The most significant BFV increase was obtained during performance of TMTB.

Conclusion

Our result addressed cognitive tests with great activation potential for monitoring of ACAs that might be used in distinguishing of healthy individuals and patients with neurovascular or neurodegenerative diseases.     

Embedding Logics into Product Logic

We construct a faithful interpretation of ukasiewicz's logic in product logic (both propositional and predicate). Using known facts it follows that the product predicate logic is not recursively axiomatizable.We prove a completeness theorem for product logic extended by a unary connective of Baaz [1]. We show that Gödel's logic is a sublogic of this extended product logic.We also prove NP-completeness of the set of propositional formulas satisfiable in product logic (resp. in Gödel's logic).     

Sicherheit Vor,Mit Rußland? Nato-osterweiterung und Folgen

Studies in East European Thought -