Motion Perception in Autism: A “Complex” Issue

2003 ◽  
Vol 15 (2) ◽  
pp. 218-225 ◽  
Author(s):  
Armando Bertone ◽  
Laurent Mottron ◽  
Patricia Jelenic ◽  
Jocelyn Faubert
Keyword(s):  
Neural Mechanisms ◽  
Neural Processing ◽  
Perceptual Integration ◽  
Complex Issue ◽  
Motion Patterns ◽  
Motion Sensitivity ◽  
First Order ◽  
Cognitive Operations ◽  
Different Types ◽  
Processing Mechanisms

We present the first assessment of motion sensitivity for persons with autism and normal intelligence using motion patterns that require neural processing mechanisms of varying complexity. Compared to matched controls, our results demonstrate that the motion sensitivity of observers with autism is similar to that of nonautistic observers for different types of first-order (luminance-defined) motion stimuli, but significantly decreased for the same types of second-order (texture-defined) stimuli. The latter class of motion stimuli has been demonstrated to require additional neural computation to be processed adequately. This finding may reflect less efficient integrative functioning of the neural mechanisms that mediate visuoperceptual processing in autism. The contribution of this finding with regards to abnormal perceptual integration in autism, its effect on cognitive operations, and possible behavioral implications are discussed.

Polarization vision – a uniform sensory capacity?

2001 ◽  
Vol 204 (14) ◽  
pp. 2589-2596 ◽  
Author(s):  
Rüdiger Wehner
Keyword(s):  
Polarized Light ◽  
Neural Mechanisms ◽  
Degree Of Polarization ◽  
Polarization Vision ◽  
Terrestrial Habitat ◽  
Spectral Content ◽  
Common Receptor ◽  
Sensory Capacity ◽  
Different Types ◽  
Processing Mechanisms

SUMMARYIn this concept paper, three scenarios are described in which animals make use of polarized light: the underwater world, the water surface and the terrestrial habitat vaulted by the pattern of polarized light in the sky. Within these various visual environments, polarized light is used in a number of ways that make quite different demands on the neural circuitries mediating these different types of behaviour. Apart from some common receptor and pre-processing mechanisms, the underlying neural mechanisms may differ accordingly. Often, information about χ (the angle of polarization), d (the degree of polarization) and λ (the spectral content) might not – and need not – be disentangled. Hence, the hypothesis entertained in this account is that polarization vision comes in various guises, and that the answer to the question posed in the title is most probably no.

Do Event-Related Brain Potentials Reflect Mental (Cognitive) Operations?

2002 ◽  
Vol 16 (3) ◽  
pp. 129-149 ◽  
Author(s):  
Boris Kotchoubey
Keyword(s):  
Cognitive Processes ◽  
Point Of View ◽  
Internal Variables ◽  
Brain Potentials ◽  
Cognitive Operations ◽  
External Variables ◽  
Series Of Experiments ◽  
Mental Operations ◽  
A Chain ◽  
Processing Mechanisms

Abstract Most cognitive psychophysiological studies assume (1) that there is a chain of (partially overlapping) cognitive processes (processing stages, mechanisms, operators) leading from stimulus to response, and (2) that components of event-related brain potentials (ERPs) may be regarded as manifestations of these processing stages. What is usually discussed is which particular processing mechanisms are related to some particular component, but not whether such a relationship exists at all. Alternatively, from the point of view of noncognitive (e. g., “naturalistic”) theories of perception ERP components might be conceived of as correlates of extraction of the information from the experimental environment. In a series of experiments, the author attempted to separate these two accounts, i. e., internal variables like mental operations or cognitive parameters versus external variables like information content of stimulation. Whenever this separation could be performed, the latter factor proved to significantly affect ERP amplitudes, whereas the former did not. These data indicate that ERPs cannot be unequivocally linked to processing mechanisms postulated by cognitive models of perception. Therefore, they cannot be regarded as support for these models.

Post-Non-Classical World View in the On-Screen Reality of the Digital Epoch

2015 ◽  
pp. 4-12
Author(s):  
Elena V. Nikolaeva
Keyword(s):  
World View ◽  
Dynamic Chaos ◽  
Digital Culture ◽  
Fractal Nature ◽  
Late 20Th Century ◽  
First Order ◽  
Classical World ◽  
Different Types ◽  
Strange Loops ◽  
Cultural World

The article analyzes the correlation between the screen reality and the first-order reality in the digital culture. Specific concepts of the scientific paradigm of the late 20th century are considered as constituent principles of the on-screen reality of the digital epoch. The study proves that the post-non-classical cultural world view, emerging from the dynamic “chaos” of informational and semantic rows of TV programs and cinematographic narrations, is of a fractal nature. The article investigates different types of fractality of the TV content and film plots, their inner and outer “strange loops” and artistic interpretations of the “butterfly effect”.

Quantitative Models of Motor Responses Subject to Longitudinal, Lateral, and Preview Constraints

1978 ◽  
Vol 20 (1) ◽  
pp. 35-39 ◽  
Author(s):  
Tarald O. Kvålseth
Keyword(s):  
Experimental Data ◽  
Motor Control ◽  
Linear Models ◽  
Movement Time ◽  
Arm Movements ◽  
Second Order ◽  
Motor Responses ◽  
First Order ◽  
Different Types ◽  
Index Of Difficulty

First- and second-order linear models of mean movement time for serial arm movements aimed at a target and subject to preview constraints and lateral constraints were formulated as extensions of the so-called Fitts's law of motor control. These models were validated on the basis of experimental data from five subjects and found to explain from 80% to 85% of the variation in movement time in the case of the first-order models and from 93% to 95% of such variation for the second-order models. Fitts's index of difficulty (ID) was generally found to contribute more to the movement time than did either the preview ID or the lateral ID defined. Of the different types of errors, target overshoots occurred far more frequently than undershoots.

Lexical-Grammatical Status and Lexicographic Presentation of Two-Component Stable Prepositional Combinations

2021 ◽  
pp. 32-51
Author(s):  
Elena V. Generalova ◽  
Keyword(s):  
Summary Table ◽  
Complex Issue ◽  
Dictionary Entry ◽  
Figurative Meaning ◽  
Advantages And Disadvantages ◽  
Unresolved Question ◽  
Two Component ◽  
Different Types ◽  
Syntactic Properties ◽  
Theoretical Issues

The aim of the article is to review the ways of dictionary presentation of stable prepositional combinations and the factors essential for their lexical-grammatical status and the type of optimal lexicographic description. The object of the study is twocomponent prepositional combinations with stable meanings and the “preposition+noun” structure. The material of the article is data of different dictionaries of Russian presenting stable prepositional combinations. In the course of the study, the following questions were answered: why the definition and interpretation of the lexical-grammatical nature of stable prepositional combinations are so difficult and ambiguous; what lexicographic interpretation these units have in dictionaries of different types; what the advantages and disadvantages of different ways of dictionary interpretation of such language material are. The following methods were used: introspective (observation, generalization, classification), systematic lexicographic description according to dictionary parameters, dictionary definition analysis. The summary table of the lexicographic presentation of stable combinations allows seeing both the unresolved question of dictionary interpretation of such units and the patterns of their interpretation depending on the type of a dictionary. As a result of the analysis the following conclusions were drawn. 1) In modern Russian there is a rather large (about 2,000 units) class of language units (prepositional combinations), the lexical-grammatical status of which is not defined, and there is no term for their definition; this class is historically formed and continues to replenish. 2) The type of dictionary presentation of stable prepositional combinations is determined by the dictionary concept, grammatical and syntactic properties, presence of figurative meaning and possibility of component variation of such combinations. 3) The unresolved theoretical issues have as a result the lexicographic discrepancy in the presentation of these language units. Extreme lexicographic solutions are a separate dictionary entry for each combination and the presentation of such units only as stable combinations in the entry of a noun (presented in academic explanatory dictionaries). 4) Taking into account only the factor of presence/absence of a gap seems to formalize the dictionary presentation of adverbs with both conjoined and split spelling, really existing in Russian, and the position of recognition of these units with independent words and their isolate presentation is not impeccable for dictionary users. 5) In the author’s opinion, the presentation of stable prepositional combinations exclusively as independent vocabules is inferior to the traditional lexicographic approach because the isolated presentation of this material breaks the semantic connections of these complex lexical units; the most complex issue is the differentiation of adverbs with split spelling and stable combinations.

Different Types of Signal Coupling in the Visual Cortex Related to Neural Mechanisms of Associative Processing and Perception

2004 ◽  
Vol 15 (5) ◽  
pp. 1039-1052 ◽  
Author(s):  
R. Eckhorn ◽  
A.M. Gail ◽  
A. Bruns ◽  
A. Gabriel ◽  
B. Al-Shaikhli ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Neural Mechanisms ◽  
Associative Processing ◽  
Different Types

Resolution in type theory

1971 ◽  
Vol 36 (3) ◽  
pp. 414-432 ◽  
Author(s):  
Peter B. Andrews
Keyword(s):  
Set Theory ◽  
Type Theory ◽  
Higher Order ◽  
Order Logic ◽  
First Order Logic ◽  
Higher Order Logic ◽  
First Order ◽  
Different Types ◽  
Axiomatic Set Theory ◽  
Order Predicate Calculus

In [8] J. A. Robinson introduced a complete refutation procedure called resolution for first order predicate calculus. Resolution is based on ideas in Herbrand's Theorem, and provides a very convenient framework in which to search for a proof of a wff believed to be a theorem. Moreover, it has proved possible to formulate many refinements of resolution which are still complete but are more efficient, at least in many contexts. However, when efficiency is a prime consideration, the restriction to first order logic is unfortunate, since many statements of mathematics (and other disciplines) can be expressed more simply and naturally in higher order logic than in first order logic. Also, the fact that in higher order logic (as in many-sorted first order logic) there is an explicit syntactic distinction between expressions which denote different types of intuitive objects is of great value where matching is involved, since one is automatically prevented from trying to make certain inappropriate matches. (One may contrast this with the situation in which mathematical statements are expressed in the symbolism of axiomatic set theory.).

Distinct profiles of stimulus specific cortical activity for ignoring distraction during working memory encoding and maintenance, and associations with performance

2020 ◽  
Author(s):  
Charlotte Ashton ◽  
André Gouws ◽  
Marcus Glennon ◽  
THEODORE ZANTO ◽  
Steve Tipper ◽  
...  
Keyword(s):  
Working Memory ◽  
Individual Differences ◽  
Relevant Information ◽  
Cortical Activity ◽  
Irrelevant Information ◽  
Neural Mechanisms ◽  
Memory Encoding ◽  
Different Types ◽  
Short Time

Abstract Our ability to hold information in mind for a short time (working memory) is separately predicted by our ability to ignore two types of distraction: distraction that occurs while we put information into working memory (encoding) and distraction that occurs while we maintain already encoded information within working memory. This suggests that ignoring these different types of distraction involves distinct mechanisms which separately limit performance. Here we used fMRI to measure category-sensitive cortical activity and probe these mechanisms. The results reveal specific neural mechanisms by which relevant information is remembered and irrelevant information is ignored, which contribute to intra-individual differences in WM performance.

scholarly journals Scalar field cosmology in Lyra's geometry

2015 ◽  
Vol 3 (2) ◽  
pp. 117 ◽  
Author(s):  
V. K. Shchigolev ◽  
E. A. Semenova
Keyword(s):  
Exact Solution ◽  
Scalar Field ◽  
Generating Function ◽  
Function Method ◽  
Scalar Fields ◽  
First Order ◽  
Homogeneous Cosmological Models ◽  
Different Types ◽  
Lyra’S Geometry ◽  
Scalar Field Cosmology

<p>The new classes of homogeneous cosmological models for the scalar fields are build in the context of Lyra’s geometry. The different types of exact solution for the model are obtained by applying two procedures, viz the generating function method and the first order formalism.</p>

On the undecidability of finite planar graphs

1971 ◽  
Vol 36 (1) ◽  
pp. 121-126 ◽  
Author(s):  
Solomon Garfunkel ◽  
Herbert Shank
Keyword(s):  
Planar Graphs ◽  
Equivalence Relations ◽  
Original Graph ◽  
First Order ◽  
Semantic Embedding ◽  
Different Types ◽  
Hereditary Undecidability

In this paper we demonstrate the hereditary undecidability of finite planar graphs. In §2 we introduce the preliminary logical notions used and outline the Rabin–Scott method of semantic embedding. This method is illustrated in §3 by proving the undecidability of the theory of two finite equivalence relations of a special type. In §4 we give a proof of the main theorem by embedding these equivalence relations into finite planar graphs.The basic idea is first to form a graph which codes a pair of these relations and then to take a representative of it and “squish” it to the plane. This “squishing” requires the introduction of crossings; and edges of the original graph become paths in the new one. To distinguish the original edges we place two different types of “diamonds” about crossing points. We can then uncode our new graphs to recover the equivalence relations by means of simple first-order incidence properties.

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