2,515 research outputs found

    Face Cognition: A Set of Distinct Mental Abilities

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    Perceiving, learning, and recognizing faces swiftly and accurately is of paramount importance to humans as a social species. Though established functional models of face cognition<sup>1,2</sup> suggest the existence of multiple abilities in face cognition, the number of such abilities and the relationships among them and to other cognitive abilities can only be determined by studying individual differences. Here we investigated individual differences in a broad variety of indicators of face cognition and identified for the first time three component abilities: face perception, face memory, and the speed of face cognition. These component abilities were replicated in an independent study and were found to be robustly separable from established cognitive abilities, specifically immediate and delayed memory, mental speed, general cognitive ability, and object cognition. The analysis of individual differences goes beyond functional and neurological models of face cognition by demonstrating the difference between face perception and face learning, and by making evident the distinction between speed and accuracy of face cognition. Our indicators also provide a means to develop tests and training programs for face cognition that are broader and more precise than those currently available).<sup>3,4</sup&#x3e

    Attentional modulation of orthographic neighborhood effects during reading: Evidence from event-related brain potentials in a psychological refractory period paradigm

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    It is often assumed that word reading proceeds automatically. Here, we tested this assumption by recording event-related potentials during a psychological refractory period (PRP) paradigm, requiring lexical decisions about written words. Specifically, we selected words differing in their orthographic neighborhood size–the number of words that can be obtained from a target by exchanging a single letter–and investigated how influences of this variable depend on the availability of central attention. As expected, when attentional resources for lexical decisions were unconstrained, words with many orthographic neighbors elicited larger N400 amplitudes than those with few neighbors. However, under conditions of high temporal overlap with a high priority primary task, the N400 effect was not statistically different from zero. This finding indicates strong attentional influences on processes sensitive to orthographic neighbors during word reading, providing novel evidence against the full automaticity of processes involved in word reading. Furthermore, in conjunction with the observation of an underadditive interaction between stimulus onset asynchrony (SOA) and orthographic neighborhood size in lexical decision performance, commonly taken to indicate automaticity, our results raise issues concerning the standard logic of cognitive slack in the PRP paradigm

    Seeing what we know and understand

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    Expertise in object recognition, as in bird watching or X-ray specialization, is based on extensive perceptual experience and in-depth semantic knowledge. Although it has been shown that rich perceptual experience shapes elementary perception and higher level discrimination and identification, little is known about the influence of in-depth semantic knowledge on object perception and identification. By means of recording event-related brain potentials (ERPs), we show that the amount of knowledge acquired about initially unfamiliar objects modulates visual ERP components already 120 msec after object presentation, and causes gradual variations of activity in similar brain systems within a later timeframe commonly associated with meaning access. When perceptual analysis is made more difficult by blurring object pictures, knowledge has an even stronger effect on perceptual analysis and facilitates recognition. These findings demonstrate that in-depth knowledge not only affects involuntary semantic memory access, but also shapes perception by penetrating early visual processes traditionally held to be immune to such influences.Peer Reviewe

    Reconstructing ERP amplitude effects after compensating for trial-to-trial latency jitter: A solution based on a novel application of residue iteration decomposition

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    © 2016 The Authors Stimulus-locked averaged event-related potentials (ERPs) are among the most frequently used signals in Cognitive Neuroscience. However, the late, cognitive or endogenous ERP components are often variable in latency from trial to trial in a component-specific way, compromising the stability assumption underlying the averaging scheme. Here we show that trial-to-trial latency variability of ERP components not only blurs the average ERP waveforms, but may also attenuate existing or artificially induce condition effects in amplitude. Hitherto this problem has not been well investigated. To tackle this problem, a method to measure and compensate component-specific trial-to-trial latency variability is required. Here we first systematically analyze the problem of single trial latency variability for condition effects based on simulation. Then, we introduce a solution by applying residue iteration decomposition (RIDE) to experimental data. RIDE separates different clusters of ERP components according to their time-locking to stimulus onsets, response times, or neither, based on an algorithm of iterative subtraction. We suggest to reconstruct ERPs by re-aligning the component clusters to their most probable single trial latencies. We demonstrate that RIDE-reconstructed ERPs may recover amplitude effects that are diminished or exaggerated in conventional averages by trial-to-trial latency jitter. Hence, RIDE-corrected ERPs may be a valuable tool in conditions where ERP effects may be compromised by latency variability.Link_to_subscribed_fulltex

    Childhood trauma and violent behavior in adolescents are differentially related to cognitive-emotional deficits

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    Introduction Converging neurobiological and epidemiological evidence indicates that exposure to traumatic events in the early stages of development, that is, adverse childhood experiences (ACEs), negatively affects the likelihood of being involved in violent behavior later in life. These problems are hypothesized to be mediated by the disruption of executive functions, in particular, the ability to inhibit inappropriate actions. Here we aimed to distinguish the contribution of inhibition in non-emotional and emotional situations (i.e., emotion regulation) and assessed the modulating influence of stress, testing Nairobi county high school students in a two-experiment study. Methods In Experiment 1, neutral and emotional inhibition, working memory, and fluid intelligence were measured alongside questionnaires about ACE and violent behavior. Experiment 2 replicated these relations in an independent sample and assessed whether they would be aggravated after acute experimentally induced stress. Results Experiment 1 results showed that ACE was positively related to both non-emotional and emotional inhibition; in contrast, violent behavior was only associated with deficient emotional inhibition. Experiment 2 findings showed that stress did not significantly affect the relation of ACE to non-emotional inhibition and emotion regulation; however, it increased deficits of violent participants in their ability to down-regulate emotions. Discussion Together, results suggest that deficits in emotion regulation, especially under stressful conditions, are more critical than impairments in non-emotional inhibition in predicting violent behavior in victims of childhood trauma. These findings open perspectives toward more targeted research and interventions.Peer Reviewe

    On the structure of motor programming: an additive factors approach

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    Die evangelische Kirche A. B. in Wien Gumpendorf

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    In dieser Arbeit wird die evangelische Kirche in Wien Gumpendorf, heute genannt Gustav-Adolf-Kirche, näher beleuchtet. Einleitend wird kurz die Geschichte protestantischer Gotteshäuser unter besonderer Berücksichtigung der rechtlichen Situation im Habsburgerreich referiert. Es folgt die Beschreibung der beiden Wiener evangelischen Kirchen, die zum Baubeginn der Kirche in Gumpendorf bereits bestanden hatten. Im Hauptkapitel wird zunächst auf die beiden beteiligten Architekten - Christian Ludwig Förster und Theophil Hansen - eingegangen, gefolgt von der Beschreibung von Außenbau und Innenraum der Gustav-Adolf-Kirche. Anschließend werden einige Vorgänger- sowie Nachfolgebauten aufgelistet und in Beziehung zur Gumpendorfer Kirche gesetzt. In den abschließenden Kapiteln wird auf die zeitgenössische Stildiskussion, insbesondere auf den so genannten "orientalischen Stil" in der Sakralarchitektur eingegangen

    The time course of semantic richness effects in visual word recognition

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    The richness of semantic representations associated with individual words has emerged as an important variable in reading. In the present study we contrasted different measures of semantic richness and explored the time course of their influences during visual word processing as reflected in event-related brain potentials (ERPs). ERPs were recorded while participants performed a lexical decision task on visually presented words and pseudowords. For word stimuli, we orthogonally manipulated two frequently employed measures of semantic richness: the number of semantic features generated in feature-listing tasks and the number of associates based on free association norms. We did not find any influence of the number of associates. In contrast, the number of semantic features modulated ERP amplitudes at central sites starting at about 190 ms, as well as during the later N400 component over centro-parietal regions (300–500 ms). Thus, initial access to semantic representations of single words is fast and word meaning continues to modulate processing later on during reading

    The Left-Side Bias Is Reduced to Other-Race Faces in Caucasian Individuals

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    One stable marker of face perception appears to be left-side bias, the tendency to rely more on information conveyed by the left side of the face than the right. Previous studies have shown that left-side bias is influenced by familiarity and prior experience with face stimuli. Since other-race facial recognition is characterized by reduced familiarity, in contrast to own-race facial recognition, the phenomenon of left-side bias is expected to be weaker for other-race faces. Among Chinese participants, face inversion has been found to eliminate the left-side bias associated with own-race faces. Therefore, it is of interest to know whether face inversion influences left-side bias for non-Chinese research participants and can be generalized across own- and other-race faces. This study assessed 65 Caucasian participants using upright and inverted chimeric Caucasian and Asian faces in an identity similarity-judgment task. Although a significant left-side bias was observed for upright own-race faces, this bias was eliminated by facial inversion, indicating that such a bias depends on the applicability of configural processing strategies. For other-race faces, there was no left-side bias in the upright condition. Interestingly, the inverted presentation yielded a right-side bias. These results show that while left-side bias is affected by familiarity differences between own- and other-race faces, it is a universal phenomenon for upright faces. Inverted presentation strongly reduces left-side bias and may even cause it to revert to right-side bias, suggesting that left-side bias depends on configural face processing.Peer Reviewe

    Phylogeny of the nematode genus Pristionchus and implications for biodiversity, biogeography and the evolution of hermaphroditism

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    <p>Abstract</p> <p>Background</p> <p>The nematode <it>Pristionchus pacificus </it>has originally been developed as a satellite organism for comparison to <it>Caenorhabditis elegans</it>. A 10X coverage of the whole genome of <it>P. pacificus </it>is available, making <it>P. pacificus </it>the first non-<it>Caenorhabditis </it>nematode with a fully sequenced genome. The macroevolutionary comparison between <it>P. pacificus </it>and <it>C. elegans </it>has been complemented by microevolutionary studies of closely related strains and species within the genus <it>Pristionchus</it>. In addition, new understanding of the biology of <it>Pristionchus </it>from field studies, demonstrating a close association with various scarab beetles and the Colorado potato beetle, supports consideration of this nematode in studies of ecosystems. In the course of field studies on four continents more than 1,200 isolates were established from 15,000 beetle specimens representing 18 <it>Pristionchus </it>species. Two remarkable features of the <it>Pristionchus </it>– beetle association are the high species specificity of the interaction and the interception of the beetle's sex communication system for host recognition by the nematodes, as suggested by chemotaxis studies. Evolutionary interpretations of differences in developmental, behavioral and ecological patterns require a phylogenetic framework of the genus <it>Pristionchus</it>.</p> <p>Results</p> <p>Here, we provide a robust phylogeny of all 18 available <it>Pristionchus </it>species based on a set of 27 ribosomal protein genes encompassing a total of 10,971 bp. The phylogenetic tree provides evidence for North American and European clades, which are embedded in a deeper clade that includes Asian species. It also indicates putative invasion events. Of the 18 <it>Pristionchus </it>species, 13 are gonochoristic and five are hermaphroditic. The phylogeny indicates that all hermaphroditic species have arisen independently within the genus <it>Pristionchus</it>.</p> <p>Conclusion</p> <p>Combined ribosomal protein cDNA data can provide the basis for reconstruction of a robust phylogenetic framework for microevolutionary and biogeographic analyses. An additional major implication of our studies is the use of <it>Pristionchus </it>for nematode biodiversity assessments. While some species are represented by more than 100 isolates, others were found less than four times. Such patterns were observed on all continents and in all phylogenetic clades indicating that species asymmetry is a widespread phenomenon, which can now be further investigated by molecular tools.</p
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