Ensemble summary statistics as a basis for rapid visual categorization
Ensemble summary statistics represent multiple objects on the high level of abstraction—that is, without representing individual features and ignoring spatial organization. This makes them especially useful for the rapid visual categorization of multiple objects of different types that are intermixed in space. Rapid categorization implies our ability to judge at one brief glance whether all visible objects represent different types or just variants of one type. A framework presented here states that processes resembling statistical tests can underlie that categorization. At an early stage (primary categorization), when independent ensemble properties are distributed along a single sensory dimension, the shape of that distribution is tested in order to establish whether all features can be represented by a single or multiple peaks. When primary categories are separated, the visual system either reiterates the shape test to recognize subcategories (indepth processing) or implements mean comparison tests to match several primary categories along a new dimension. Rapid categorization is not free from processing limitations; the role of selective attention in categorization is discussed in light of these limitations.
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.
It is well known, that even in optimal conditions animals and humans make spontaneous errors which are the most prominent manifestations of attention system failures. Our goal was to investigate the causes of attention system failures in normal state of arousal and without distracting objects. We have designed a new task which allows to answer the following question: which stage of sensory processing is compromised during attention lapses?
The effect of conceptual flexibility involves inclusion of attributes that are irrelevant to the formed category in the concept and their further handling where required. The previous studies show that the conceptual flexibility effect arises while performing feature inference tasks and doesn’t arise while performing classification tasks. In the last case attention becomes too focused on one attribute. In the study the hypothesis according to which the conceptual flexibility effect may arise while performing classification tasks is tested on a sample of students (N=60). As this take place objects with attributes that are functionally connected and potentially related to semantic knowledge of the students are used as stimuli.
The material of the present paper is grounded on the holist algebraic method (Q-analysis) proposed by English mathematician and physicist R.H.Atkin. At its core, the approach is aimed at both analysis of systems structures (in the form of simplicial complexes K, which is formed by a set of properly adjoined objects called simplexes) and calculation of numeric estimates of structural complexity of systems based on the results of such analysis.
Turning complexity estimate of system’s structure into a real number creates additional difficulties in the comparison of two different complexes because there is no real verbal scale, which would have been accustomed to human beings and would allow a group of experts to express opinions and draw easily conclusions about degree of complexity of K at each particular dimensional level of its analysis. Therefore, the present paper deals with consideration of the approach that is more focused on human perception of characteristics obtained, mental comprehension and formation (comparison) of personal constructs in psychological space (or, P-space) – modified structural complexity estimate is based right on notions of distance and similarity within psychological space.
The world that we perceive and describe changes constantly. If we believe our descriptions of the world to be accurate and consistent, we must assume that the content and the structure of our individual sentences accurately and consistently reflect the world’s constantly changing nature. If so, a comprehensive production system must model the sentence generation process taking into account this basic assumption: Words, their linear arrangement, and the structures they are inserted in must somehow reflect the corresponding parameters of the observed and described event. This system must include representation of salience as one integral component resulting in interplay that involves constant, regular, and automatic mappings between elements of a visual scene, their varying salience, and the structural arrangement of the sentence constituents and the grammatical relations between them. In this interplay, perceptual input contributes initially to this mapping process by providing information for further conceptual and linguistic encoding. Importantly, this information is not processed in an unconstrained fashion; instead, it is systematically filtered, selected, and relayed based on a regular interface between the aspects of attention and their corresponding counterparts in the conceptual and linguistic structures. Bottom-up and top-down features of this interface include noticeability, importance, or relevance. As a result, linguistic output reflects the event’s conceptual organization including the attentional state of the speaker in a regular way. This mapping between attentional focus and structural choice is a part of a more complex mapping mechanism that we will refer to as Cognition-Language Interface or CLI. Specifically, this Chapter will consider theoretical and empirical knowledge about the complex interplay between the speaker’s attentional state and the structural choices they make during sentence production.
Distractor's effect (stimulus which is irrelevant at a certain moment and ignored) on task solving efficiency is considered. It is revealed that according to problem situation and connection with target stimulus any distractor can produce two opposite effects: negative - interference and positive - redundancy effect. Distractor effects' classification based on one of possible grounds - distractor's source: sensory inputs effects, hierarchical effects and correlational effects is given. Possibility of level-hierarchical relation between the three classes of effects is discussed.
Our experimental study looked into the way existing knowledge influences the way subjects con- struct the rules of categorization and modify them as they are applied. We modified the experiment of E. Wisniewski and D. Medina (1994) by asking the respondents not only to create a categorization rule, but also to use it to categorize new images, and we looked at the frequency and type of subsequent rule modification. The respondents, 114 university students, were given a set of images drawn by children and asked to identify their common features under one of the four conditions: relevant prior knowledge (participants were told that the drawings had been made by children with high and low creativity), stan- dard condition (participants were told the drawings had been made by children from groups A and B), standard condition with examples (one sample of drawings from each group was shown), and irrelevant knowledge. We found that under the relevant prior knowledge condition, compared to the other three conditions, the respondents tended to construct more complex and abstract rules and to change them more frequently when they categorized new objects. We also found that rule modifications during usage led to more complex and abstract rules under all four conditions. We interpret the findings as evidence for two stages of categorization, the first stage involving search for existing generalizations in semantic memory, and the second stage involving adaptation of prior knowledge to current conditions.
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.