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D Todorović

Publications and source records attributed to D Todorović.

12 recordsLinked to original sources
PubMed1997

Lightness and junctions.

The lightness of a test patch completely surrounded by an inducing field can be predicted by variants of Wallach's ratio rule. When a patch is surrounded by two or more regions with different luminances, a plausible extension of the ratio rule would predict that the effect of the surrounding regions should correlate with the length of the border they share with the test patch. However, as shown by the Wertheimer-Benary and White effects, lightness of such patches can depart appreciably from these predictions. It is argued that a fruitful approach toward the explanation of such effects is based on the analysis of junctions (such as T-junctions and X-junctions) between regions. Several new displays and variations of old displays involving such junctions are used to illustrate this approach. An alternative analysis of a lightness effect introduced by Adelson is provided, and the role of depth effects in achromatic perception is discussed. A number of limitations of the approach and possible ways to overcome them are noted.

Contrast Sensitivity↗
PubMed1991

Is alphabet biasing in bialphabetical word perception automatic and prelexical?

Phonologically ambiguous Serbo-Croatian words are identified more slowly and erroneously than their phonologically unique counterparts. Five experiments addressed the reduction of these ambiguity effects when Roman (Cyrillic) targets are preceded by consonants unique to the Roman (Cyrillic) alphabet. Alphabet-specific nonword contexts were presented briefly with masking. With forward masking, performance was better when the phonologically ambiguous target words and their preceding nonword contexts were alphabetically congruent. Similarly, where backward masked contexts acted themselves as backward masks for the target stimuli, identification was highest when the context masks were in the same alphabet as the targets. Results were discussed in terms of automatic, prelexical processes within a network model of visual word recognition in Serbo-Croatian.

Adolescent↗
PubMed1991

Deletion analysis of Duchenne muscular dystrophy using cDNA probes and multiplex PCR.

The authors studied Duchenne muscular dystrophy (DMD) in 14 Yugoslav families with 16 diseased men. All the sixteen patients showed typical phenotypic features of DMD. The linkage analysis was done with five probes 754, C7, PERT87.15, pERT87.30, and pERTBir. A deletion with pERT87.15 (DX 164) in one family was found. Deletion analysis was mainly performed using cDNA probes and multiplex PCR analysis. Preferential deletions were in the hot spot deletion region covered by cDNA probe 8. Among 14 examined patients with cDNA hybridization deletions were found in 5 cases (5/14). For quick and prenatal analysis the authors used multiplex PCR. With this methods deletions were found in 4 cases (4/15). The percentage of the observed deletions cases was 50% (8/16) in Yugoslav population, which shows good correlation with other European and American populations studied. Prenatal diagnosis was done for two consultants with highly ambiguous carrier risk, and no deletions were found.

Child↗
PubMed1989

A neural network architecture for preattentive vision.

Recent results towards development of a neural network architecture for general-purpose preattentive vision are summarized. The architecture contains two parallel subsystems, the boundary contour system (BCS) and the feature contour system (FCS), which interact together to generate a representation of form-and-color-and-depth. Emergent boundary segmentation within the BCS and featural filling-in within the FCS are herein emphasized within a monocular setting. Applications to the analysis of boundaries, textures, and smooth surfaces are described, as is a model for invariant brightness perception under variable illumination conditions. The theory shows how suitably defined parallel and hierarchical interactions overcome computational uncertainties that necessarily exist at early processing stages. Some of the psychophysical and neurophysiological data supporting the theory's predictions are mentioned.

Artificial Intelligence↗
PubMed1988

Hemispheric differences in case processing.

Morphosyntactic capacities of normal brain hemispheres were compared in lexical decision studies involving centrally and laterally presented Serbo-Croatian nouns in different cases. Cases are distinguished by different suffixes and syntactic roles. Experiment 1 confirmed and extended previous findings of the nominative superiority effect: words in the nominative case were processed faster and more accurately than words in other three cases, and nonwords in the nominative case led to more false positive reactions than nonwords in other cases. In Experiment 2 this effect was replicated for right visual field stimuli: nominatives had faster reaction times and smaller error rates than accusatives, and the reversed pattern was found for nonwords. For left visual field stimuli, only the word error analysis found the nominative superior, while the other three analyses (word reaction times, nonword reaction times, and nonword error rates) showed no significant case effect. Word familiarity had an equally strong effect in both hemispheres. The results suggest that centrally presented stimuli are processed by the left hemisphere, that laterally presented stimuli are processed by the initially receiving hemisphere, and that the right hemisphere has a frequency-sensitive lexicon. Reduced right-hemisphere sensitivity for case differences may be due to different lexicon structure or the absence of appropriate morphological or syntactic mechanisms.

Decision Making↗
PubMed1987

Reconciling stable asymmetry with recovery of function: an adaptive systems perspective on functional plasticity.

This article examines alternative ways of resolving an apparent paradox that has emerged from neuropsychological studies of language development: How can the developmentally stable functional asymmetry ("hemispheric specialization") observed in neurologically intact children be reconciled with the dramatic recovery of function often displayed following unilateral brain damage? The alternative resolutions we consider differ most critically in the roles they assign to lesion-induced neural reorganizations versus lesion-related release of preexisting functional potentials. Though arguments are given in favor of the latter as the primary factor in functional recovery, the primary goal of the article is to clarify the conceptual issues raised by recent empirical research.

Brain↗