bluuebunny/crossref_metadata_2025_split huggingface dataset:
Search-Intensive Concept Induction
Authors: Giordana Attilio , Neri Filippo 
Published: February 2008

This paper describes REGAL, a distributed genetic algorithm-based system, designed for learning first-order logic concept descriptions from examples. The system is a hybrid of the Pittsburgh and the Michigan approaches, as the population constitutes a redundant set of partial concept descriptions, each evolved separately. In order to increase effectiveness, REGAL is specifically tailored to the concept learning task; hence, REGAL is task-dependent, but, on the other hand, domain-independent. The system proved particularly robust with respect to parameter setting across a variety of different application domains. REGAL is based on a selection operator, called Universal Suffrage operator, provably allowing the population to asymptotically converge, on the average, to an equilibrium state in which several species coexist. The system is presented in both a serial and a parallel version, and a new distributed computational model is proposed and discussed. The system has been tested on a simple artificial domain for the sake of illustration, and on several complex real-world and artificial domains in order to show its power and to analyze its behavior under various conditions. The results obtained so far suggest that genetic search may be a valuable alternative to logic-based approaches to learning concepts, when no (or little) a priori knowledge is available and a very large hypothesis space has to be explored.
Evolutionary Algorithms, Homomorphous Mappings, and Constrained Parameter Optimization
Authors: Koziel Slawomir , Michalewicz Zbigniew 
Published: February 2008

During the last five years, several methods have been proposed for handling nonlinear constraints using evolutionary algorithms (EAs) for numerical optimization problems. Recent survey papers classify these methods into four categories: preservation of feasibility, penalty functions, searching for feasibility, and other hybrids. In this paper we investigate a new approach for solving constrained numerical optimization problems which incorporates a homomorphous mapping between n-dimensional cube and a feasible search space. This approach constitutes an example of the fifth decoder-based category of constraint handling techniques. We demonstrate the power of this new approach on several test cases and discuss its further potential.
An Electrophysiological Probe of Incidental Semantic Association
Authors: Kutas Marta , Hillyard Steven A. 
Published: February 2008

Abstract
Long-latency components of event-related brain potentials (ERPs) recorded from subjects reading meaningful text are sensitive to semantic relationships among the major lexical items of sentences. In particular, the N400 components are enlarged to words that are semantically unrelated to or incongruous with the context provided by preceding items in a sentence. The present experiment was aimed at finding out whether this inverse relationship between N400 amplitude and semantic association would extend to situations where words were presented in isolated pairs, using a design that dissociated changes in N400 from confounding ERP waves elicited by active decision making. KRP's were recorded to 320 word pairs presented to eleven subjects. Each pair of words was followed by a letter, and subjects made a differential response according to whether or not the letter had been present in either of the words. After the ERP recording session, subjects rated the degree of semantic association between the words in each pair. ERP averages were formed on the basis of the subjects' ratings and on the basis of normative, a priori categories. For both types of averages the N400 amplitude was found to be a sensitive index of semantic association, even though the association was incidental to the subject's assigned task. These findings suggest the utility of the N400 measure in studies of semantic priming and as a probe of the automaticity of contextual influences in language processing.
Indelibility of Subcortical Emotional Memories
Authors: LeDoux Joseph E. , Romanski Lizabeth , Xagoraris Andrew 
Published: February 2008

Abstract
Acquisition and extinction of fear responses conditioned to a visual stimulus were examined in rats with ablations of visual cortex. Visual cortex lesions did not interfere with acquisition, indicating that visual fear conditioning, like auditory fear conditioning, is mediated by sub-cortical, probably thalamo-amygdala, sensory pathways. In contrast to acquisition, extinction was greatly prolonged, if not prevented, by cortical ablation. This resistance to extinction of sub cortical emotional memories may explain certain aspects of emotional memory in man.
Global Versus Local Processing in the Absence of Low Spatial Frequencies
Authors: Hughes H. C. , Fendrich R. , Reuter-Lorenz P. A. 
Published: February 2008

AbstractWhen observers are presented with hierarchical visual stimuli that contain incongruous coarse (“global”) and fine (“local”) pattern attributes, the global structure interferes with local pattern processing more than local structure interferes with global pattern processing. This effect is referred to as “global precedence.” The present experiments tested the hypothesis that global precedence depends on the presence of low spatial frequencies using stimuli constructed from “contrast balanced dots.” Stimuli composed of contrast balanced dots are largely devoid of low-frequency content. Choice reaction time to identify either the local or global pattern information was the dependent measure. Global precedence was found only for control stimuli that contained low spatial frequencies. In the absence of low-frequency information, local precedence was obtained. These findings suggest that global precedence is heavily dependent on the low spatial frequency content of the patterns.
Event-Related Potentials to Infrequent Changes in Synthesized Phonetic Stimuli
Authors: Sams Mikko , Aulanko Reijo , Aaltonen Olli , Näätänen Risto 
Published: February 2008

Abstract
Event-related potentials (ERPs) to synthetic consonant–vowel syllables were recorded. Infrequent changes in such a syllable elicited a "mismatch negativity" as well as an enhanced N100 component of the ERP even when subjects did not pay attention to the stimuli. Both components are probably generated in the supratemporal auditory cortex suggesting that in these areas there are neural networks that are automatically activated by speech-specific auditory stimulus features such as formant transitions.
Anterior Frontal Cortex and the Effect of Proactive Interference in Paired Associate Learning: A DC Potential Study
Authors: Uhl F. , Franzen P. , Serles W. , Lang W. , Lindinger G. , Deecke L. 
Published: February 2008

Abstract
This contribution focuses on neurophysiological correlates of the cerebral processes subserving the control of proactive interference. Event-related negative shifts of the scalp-recorded cortical steady potential (negative DC shifts) were measured in 17 right-handed normals during two tasks of paired associate learning. The control condition was a standard word pair learning task in which unrelated word pairs were presented. In the experimental condition, proactive interference was maximized by presenting very similar words and by requiring negative transfer, i.e., by having them reappear, but in different pairings. Proactive interference leads to increased anterior frontal negative DC shifts. Furthermore, centrotemporal negative DC shifts predicted subsequent cued recall performance. In spite of elaborative strategies, an effect of subsequent mnestic performance on the P300 was observed.
Deformable Templates for Face Recognition
Authors: Yuille Alan L. 
Published: February 2008

Abstract
We describe an approach for extracting facial features from images and for determining the spatial organization between these features using the concept of a deformable template. This is a parameterized geometric model of the object to be recognized together with a measure of how well it fits the image data. Variations in the parameters correspond to allowable deformations of the object and can be specified by a probabilistic model. After the extraction stage the parameters of the deformable template can be used for object description and recognition.
Alzheimer's Disease Effects on Semantic Memory: Loss of Structure or Impaired Processing?
Authors: Bayles Kathryn A. , Tomoeda Cheryl K. , Kaszniak Alfred W. , Trosset Michael W. 
Published: February 2008

Abstract
Results of several prior studies, in which Alzheimer's disease (AD) patients missed the same concepts on multiple tasks, have been used to substantiate the theory that AD causes concept-specific loss of information from semantic memory However, sample sizes in these studies are modest, test-retest intervals small, and typically only a few tasks were used. In the present study 69 An subjects were annually administered 11 tasks, each using the same 13 concepts. Only a few instances were observed in which a concept was missed across all 11 tasks. When performances on the Oral Reading and Dictation tasks were removed from analysis, because of their questionable reliance on semantic memory, the number of missed concepts rose only modestly. A substantial rise in the number of missed concepts occurred, however, when performances on the four multiple- choice tasks were removed. Interpreting the larger number of missed concepts on the five remaining generative semantic tasks as evidence of item-specific loss is problematic, nonetheless, because the generative semantic tasks were among the hardest in the battery and the frequency with which an individual subject missed a concept across all tasks accorded with the subject's dementia severity level. Results also indicate that task difficulty, more than concept specificity, determine whether a concept is missed. Overall, results suggest that a concept will “disappear” when all of the tasks in which it is a stimulus become too difficult for the patient to perform. Study results call into question the appropriateness of using batteries of effortful, attention demanding tasks for ascertaining whether AD causes item-specific loss of conceptual knowledge.
Extrageniculate Contributions to Reflex Visual Orienting in Normal Humans: A Temporal Hemifield Advantage
Authors: Rafal Robert , Henik Avishai , Smith Jean 
Published: February 2008

Abstract
Evidence is presented that the phylogenetically older retin-otectal pathway contributes to reflex orienting of visual attention in normal human subjects. The study exploited a lateralized neuroanatomic arrangement of retinotectal pathways that distinguishes them from those of the geniculostriate system; namely, more direct projections to the colliculus from the temporal hemifield. Subjects were tested under monocular viewing conditions and responded to the detection of a peripheral signal by making either a saccade to it or a choice reaction time manual keypress. Attention was summoned by noninformative peripheral precues, and the benefits and costs of attention were calculated relative to a central precue condition. Both the benefits and costs of orienting attention were greater when attention was summoned by signals in the temporal hemifield. This temporal hemifield advantage was present for both saccade and manual responses. These findings converge with observations in patients with occipital and midbrain lesions to show that the phylogenetically older retinotectal pathway retains an important role in controlling visually guided behavior; and they demonstrate the usefulness of temporal-nasal hemifield asymmetries as a marker for investigating extrageniculate vision in humans.
Dissociation of Object and Spatial Vision in Human Extrastriate Cortex: Age-Related Changes in Activation of Regional Cerebral Blood Flow Measured with [15 O]Water and Positron Emission Tomography
Authors: Grady Cheryl L. , Haxby James V. , Horwitz Barry , Schapiro Mark B. , Rapoport Stanley I. , Ungerleider Leslie G. , Mishkin Mortimer , Carson Richard E. , Herscovitch Peter 
Published: February 2008

Abstract
We previously reported selective activation of regional cerebral blood flow (rCBF) in occipitotemporal cortex during a face matching task (object vision) and activation in superior parietal cortex during a dot-location matching task (spatial vision) in young subjects, The purpose of the present study was to determine the effects of aging on these extrastriate visual processing systems. Eleven young (mean age 27 ± 4 years) and nine old (mean age 72 ± 7 years) male subjects were studied. Positron emission tomographic scans were performed using a Scanditronix PC1024–7B tomograph and H2 15O to measure rCBF. To locate brain areas that were activated by the visual tasks, pixel-by-pixel difference images were computed between images from a control task and images from the face and dot-location matching tasks. Both young and old subjects showed rCBF activation during face matching primarily in occipitotemporal cortex, and activation of superior parietal cortex during dot-location matching. Statistical comparisons of these activations showed that the old subjects had more activation of occipitotemporal cortex during the spatial task and more activation of superior parietal cortex during the object task than did the young subjects. These results show less functional separation of the dorsal and ventral visual pathways in older subjects, and may reflect an age-related reduction in the processing efficiency of these visual cortical areas.
Declarative and Nondeclarative Memory: Multiple Brain Systems Supporting Learning and Memory
Authors: Squire Larry R. 
Published: February 2008

AbstractThe topic of multiple forms of memory is considered from a biological point of view. Fact-and-event (declarative, explicit) memory is contrasted with a collection of non conscious (non-declarative, implicit) memory abilities including skills and habits, priming, and simple conditioning. Recent evidence is reviewed indicating that declarative and non declarative forms of memory have different operating characteristics and depend on separate brain systems. A brain-systems framework for understanding memory phenomena is developed in light of lesion studies involving rats, monkeys, and humans, as well as recent studies with normal humans using the divided visual field technique, event-related potentials, and positron emission tomography (PET).
Priming and Multiple Memory Systems: Perceptual Mechanisms of Implicit Memory
Authors: Schacter Daniel L. 
Published: February 2008

AbstractResearch examining the relation between explicit and implicit forms of memory has generated a great deal of evidence concerning the issue of multiple memory systems. This article focuses on an extensively studied implicit memory phenomenon, known as direct or repetition priming, and examines the hypothesis that priming effects on various tasks reflect the operation of a perceptual representation system (PRS)—a class of cortically based subsystems that operate at a presemantic level and support non conscious expressions of memory. Three PRS subsystems are examined: visual word form, structural description, and auditory word form. Pertinent cognitive, neuropsychological, and neurobiological evidence is reviewed, alternative classificatory schemes are discussed, and important conceptual and terminological issues are considered.
Bridging the Gap: Evidence from ERPs on the Processing of Unbounded Dependencies
Authors: Kluender Robert , Kutas Marta 
Published: February 2008

Abstract
Since the early days of generative grammar, the study of “unbounded dependencies” such as wh-questions and relative clauses has occupied a central place in both syntactic theory and language processing research. The problem that such constructions pose is as follows. In a normal wh-question, a wh-phrase is typically displaced to the left periphery of a clause (What did you say — to John?); this displaced constituent is often referred to as a “filler.” The vacant position (indicated in the previous example by a blank line) where it would ordinarily occur in an “echo” question (You said what to John?) is correspondingly referred to as a “gap.” Filler and gap are mutually dependent on each other since they share syntactic and semantic information essential for successful sentence interpretation. However, since sentence processing is a sequential operation, a filler cannot be assigned to its gap until some time after it has occurred. In other words, the filler must be held in working memory until such time as filler-gap assignment can take place. The intent of the research reported here was to examine the processing of unbounded dependencies in English as revealed in event-related brain potentials (ERPs). To this end, subjects were shown both grammatical and ungrammatical yes/no-questions (Did you say something to John?) and wh-questions. A number of comparisons made at various points in these questions showed that both the storage of a filler in working memory and its subsequent retrieval for filler-gap assignment were associated with an enhanced negativity between 300 and 500 msec poststimulus over left anterior sites. This effect of left anterior negativity (LAN) was independent of and orthogonal to the grammaticality of the eliciting condition. We show how this interpretation coincides with recent studies that demonstrate a correlation between left anterior negativity, working memory capacity, and successful language processing.
Visual Extinction and Stimulus Repetition
Authors: Baylis Gordon C. , Driver Jon , Rafal Robert D. 
Published: February 2008

Abstract
Five patients with visual extinction following unilateral brain injury were briefly presented with colored letters in either or both visual fields, and required to report and locate the colors or the shapes. On double simultaneous stimulation, they tended to miss the event contralateral to their lesion. This extinction was increased when the two stimuli were the same on the reported dimension, Similarity on the irrelevant dimension had no effect. These data suggest that extinguished colors and shapes may be correctly extracted by the visual system (when task-relaant) even though they are unavailable for verbal report. An analogy is made with the phenomena of “repetition blindness” in normal observers, and it is proposed that extinction may reflect failure in a token-individuation process for correctly extracted visual types.
On Language
Authors: Pinker Steven 
Published: February 2008

Abstract
Steven Pinker is a professor in the Department of Brain and Cognitive Sciences at MIT, and in 1994 will become director of its McDonnell-Pew Center for Cognitive Neuroscience. He received his B.K from McGill University in 1976 and his Ph.D. from Harvard University in 1979, both in experimental psychology, and taught at Harvard and Stanford before joining the faculty of MIT in 1982. He has done research in visual cognition and the psychology of language, and is the author of Language Learnability and Language Development (1984) and Learnability and Cognition (1989) and the editor of Visual Cognition (1985), Connections and Symbol (1988, with Jacques Mehler), and Lexical and Conceptual Semantics (1992, with Beth Levin). He was the recipient of the Early Career Award in 1984 and the Boyd McCandless Award in 1986 from the American Psychological Association, a Graduate Teaching Award from MIT in 1986, and the Troland Research Award from the National Academy of Sciences in 1993. His newest book, The Language Instinct, will be published by William Morrow & Company in January 1994.
Susceptibility to Memory Interference Effects following Frontal Lobe Damage: Findings from Tests of Paired-Associate Learning
Authors: Shimamura Arthur P. , Jurica Paul J. , Mangels Jennifer A. , Gershberg Felick B. , Knight Robert T. 
Published: February 2008

Abstract
Patients with frontal lobe lesions were adminstered tests of paired-associate learning in which cue and response words are manipulated to increase interference across two study lists. In one test of paired-associate learning (AB-AC test), cue words used in one list are repeated in a second list but are associated with different response words (e.g., LION-HUNTER, LION-CIRCUS). In another test (AB-ABr test), words used in one list are repeated in a second list but are rearranged to form new pairs. Compared to control subjects, patients with frontal lobe lesions exhibited disproportionate impairment of second-list learning as a result of interference effects. In particular, patients exhibited the poorest performance during the initial trial of the second list, a trial in which interference effects from the first list would be most apparent. These findings suggest that the on-line control of irrelevant or competing memory associations is disrupted following frontal lobe lesions. This disruption may be indicative of an impaired gating or filtering mechanism that affects not only memory function but other cognitive function as well.
Representation of Grammatical Categories of Words in the Brain
Authors: Hillis Argye E. , Caramazza Alfonso 
Published: February 2008

Abstract
We report the performance of a patient who, as a consequence of left frontal and temporoparietal strokes, makes far more errors on nouns than on verbs in spoken output tasks, but makes far more errors on verbs than on nouns in written input tasks. This double dissociation within a single patient with respect to grammatical category provides evidence for the hypothesis that phonological and orthographic representations of nouns and verbs are processed by independent neural mechanisms. Furthermore, the opposite dissociation in the verbal output modality, an advantage for nouns over verbs in spoken tasks, by a different patient using the same stimuli has also been reported (Caramazza & Hillis, 1991). This double dissociation across patients on the same task indicates that results cannot be ascribed to "greater difficulty" with one type of stimulus, and provides further evidence for the view that grammatical category information is an important organizational principle of lexical knowledge in the brain.
Modulation of Event-Related Potentials by Semantic Priming: Effects of Color-Cued Selective Attention
Authors: Kellenbach Marion L. , Michie Patricia T. 
Published: February 2008

Abstract
The processing nature of N400, an event-related brain potential (ERP) component associated with semantic processing, was investigated in a paradigm combining a semantic priming lexical decision task and color-cued selective attention. Semantic priming effects on ERPs and reaction time (RT) were examined when targets and preceding semantically related primes were either both attended or both unattended, and when only either the prime or target was the focus of attention. Priming effects were determined by comparing semantically primed target ERPs (and RTs when appropriate) to their prime (in those conditions where the prime and target had the same attentional status) and/or to an unprimed control target matched to the attentional status of the primed target. Control stimuli were examined for ERP effects of color-cued selective attention unconfounded by priming factors. Experiment 1 required overt responses to words and nonwords in a binary choice task, while Experiment 2 required response only to nonwords. RTs in Experiment 1 indicated facilitatory priming effects to all semantically primed attended targets. In Experiments 1 and 2 ERPs to primes and controls were consistently more negative than the primed target trace in the N400 latency range in conditions with attended primes, suggesting priming effects on N400 are contingent on attentional processing of the prime. Removal of the attention manipulation (Experiment 3) resulted in an N400 component with a well-defined peak not evident in the first two experiments, indicating modulation of N400 by overlapping effects of attention.