Interplay between the Ebbinghaus illusion and hierarchical coding in visual working memory
Previous research has documented the limited capacity of visual working memory (VWM) for color objects set at 3–5 items. Another line of research has shown that multiple objects can be stored in a compressed form of ensemble. However, existing data is more likely to testify that VWM can store no more than two such compressed units. But the nature of this discrepancy can be methodological: VWM for ensembles was never tested using methods that are applied in the research of VWM for objects. Here we have tested the capacity and precision of VWM for objects and ensembles using two standard methods — change detection and continuous report with a mixture model. We found that VWM for both types of units showed the similar capacity and precision when critical psychophysical parameters, such as foveal density and area are controlled. We also showed that this quantitative similarity between objects and ensembles is provided by a mechanism that represents each ensemble as a holistic VWM chunk as efficiently as it represents any single object.
This article reviews the research in visual working memory (VWM) over the past 20 years. We describe research methodologies in the field and focus on commonly used paradigms such as change detection and continuous report (including the use of mixed models for analysis) that aim to measure the capacity and precision of VWM. We also consider the organization of units of storage in VWM; in particular, we describe feature binding and representing multiple objects as ensemble summary statistics. We review theories that try to explain the nature of VWM limitations: structural theories (slot-based), resource theories, hybrid theories (slot and resource theories), and a recently suggested hierarchical encoding theory. Theories aiming to explain forgetting mechanisms in VWM are reviewed. We also discuss the neural correlates of VWM encoding and storage, as well as neurophysiological models of VWM that are substantially influenced by the mentioned theories.
The distractive effects on attentional task performance in different paradigms are analyzed in this paper. I demonstrate how distractors may negatively affect (interference effect), positively (redundancy effect) or neutrally (null effect). Distractor effects described in literature are classified in accordance with their hypothetical source. The general rule of the theory is also introduced. It contains the formal prediction of the particular distractor effect, based on entropy and redundancy measures from the mathematical theory of communication (Shannon, 1948). Single- vs dual-process frameworks are considered for hypothetical mechanisms which underpin the distractor effects. Distractor profiles (DPs) are also introduced for the formalization and simple visualization of experimental data concerning the distractor effects. Typical shapes of DPs and their interpretations are discussed with examples from three frequently cited experiments. Finally, the paper introduces hierarchical hypothesis that states the level-fashion modulating interrelations between distractor effects of different classes.
This article describes the expierence of studying factors influencing the social well-being of educational migrants as mesured by means of a psychological well-being scale (A. Perrudet-Badoux, G.A. Mendelsohn, J.Chiche, 1988) previously adapted for Russian by M.V. Sokolova. A statistical analysis of the scale's reliability is performed. Trends in dynamics of subjective well-being are indentified on the basis the correlations analysis between the condbtbions of adaptation and its success rate, and potential mechanisms for developing subjective well-being among student migrants living in student hostels are described. Particular attention is paid to commuting as a factor of adaptation.