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The present study aimed to investigate whether contextual factors influence how a reference is processed in discourse. We used intact and violated presuppositions (PSP), triggered by a definite or indefinite noun phrase, to monitor the reference process. In one sentence set, a contextual referent was explicitly mentioned close or far from the PSP-triggering noun phrase (memory context). In another sentence set, a referent was not explicitly mentioned in the context, but an inference to a referent was either plausible or implausible due to contextual semantic relations (inference context). Participants were asked to rate the coherence of the discourse after listening to it. Our results revealed a strong influence of the temporal distance of the contextual presentation of a referent. When the referent was far in the context (memory context), PSP violations were judged to be less severe than for close referents, suggesting that they are less clearly represented in memory. Furthermore, PSP violations seemed to play a subordinate role when the semantic context provided a basis for the plausible presence of a referent (inference context). Our results suggest that discourse comprehension involves referential processes whose importance may fade with distance in memory or may be obscured by semantic contextual content. [ABSTRACT FROM AUTHOR]

Blind people can learn to understand speech at ultra-high syllable rates (ca. 20 syllables/s), a capability associated with hemodynamic activation of the central-visual system. To further elucidate the neural mechanisms underlying this skill, magnetoencephalographic (MEG) measurements during listening to sentence utterances were cross-correlated with time courses derived from the speech signal (envelope, syllable onsets and pitch periodicity) to capture phase-locked MEG components (14 blind, 12 sighted subjects; speech rate = 8 or 16 syllables/s, pre-defined source regions: auditory and visual cortex, inferior frontal gyrus). Blind individuals showed stronger phase locking in auditory cortex than sighted controls, and right-hemisphere visual cortex activity correlated with syllable onsets in case of ultra-fast speech. Furthermore, inferior-frontal MEG components time-locked to pitch periodicity displayed opposite lateralization effects in sighted (towards right hemisphere) and blind subjects (left). Thus, ultra-fast speech comprehension in blind individuals appears associated with changes in early signal-related processing mechanisms both within and outside the central-auditory terrain. (Contains 4 tables and 6 figures.)

Awareness of one’s own strengths and weaknesses is a key qualification for the specialist physician. We examined how physicians undergoing specialist training in general medicine rate themselves in different areas.For this purpose, 139 participants receiving post-graduate training in general practice offered by the Medical Association of Westfalen-Lippe assessed themselves regarding their subjective confidence in 20 core competencies and 47 situations involving patient counseling in general practice. Their self-assessments were recorded on a five-point Likert scale. The study questions addressed acceptance and practicability of self-assessment, mean values, reliability, stratification and plausibility of the results in group comparison.On average participants rated their subjective confidence with 3.4 out of 5 points. The results are self-consistent (Cronbach’s alpha >0.8), although there are considerable differences among competencies and among participants. The latter can be explained partly by biographical data, which supports the plausibility of the data.Participants stated that regularly gathering data on subjective learning needs and the discussion of these needs with mentors and trainers contributes to improving their specialist training.Elements for self-assessment are suitable for integration into a postgraduate training portfolio. These should be supplemented by formative assessment procedures.

The Asperger syndrome (AS) includes impaired recognition of other people's mental states. Since language-based diagnostic procedures may be confounded by cognitive-linguistic compensation strategies, nonverbal test materials were created, including human affective and vegetative sounds. Depending on video context, each sound could be interpreted either as direct expression of an agent's affective/vegetative state or as result of intentional-executive mental operations. "Situational relevance" and "intentionality" ratings by a group of twelve healthy subjects nicely differentiated between context types. By contrast, an AS subject showed a systematic overinterpretation of vegetative/affective signals in terms of planned activities. Such overestimation of intentional motivation, leading to impaired social cognition, might be due to the inability to utilize "affective resonance" mechanisms for the interpretation of an individual's internal state.

During speech communication, visual information may interact with the auditory system at various processing stages. Most noteworthy, recent magnetoencephalography (MEG) data provided first evidence for early and preattentive phonetic/phonological encoding of the visual data stream--prior to its fusion with auditory phonological features [Hertrich, I., Mathiak, K., Lutzenberger, W., & Ackermann, H. Time course of early audiovisual interactions during speech and non-speech central-auditory processing: An MEG study. "Journal of Cognitive Neuroscience, 21," 259-274, 2009]. Using functional magnetic resonance imaging, the present follow-up study aims to further elucidate the topographic distribution of visual-phonological operations and audiovisual (AV) interactions during speech perception. Ambiguous acoustic syllables--disambiguated to /pa/ or /ta/ by the visual channel (speaking face)--served as test materials, concomitant with various control conditions (nonspeech AV signals, visual-only and acoustic-only speech, and nonspeech stimuli). (i) Visual speech yielded an AV-subadditive activation of primary auditory cortex and the anterior superior temporal gyrus (STG), whereas the posterior STG responded both to speech and nonspeech motion. (ii) The inferior frontal and the fusiform gyrus of the right hemisphere showed a strong phonetic/phonological impact (differential effects of visual /pa/ vs. /ta/) upon hemodynamic activation during presentation of speaking faces. Taken together with the previous MEG data, these results point at a dual-pathway model of visual speech information processing: On the one hand, access to the auditory system via the anterior supratemporal "what" path may give rise to direct activation of "auditory objects." On the other hand, visual speech information seems to be represented in a right-hemisphere visual working memory, providing a potential basis for later interactions with auditory information such as the McGurk effect.

Study is conducted to elucidate the role of the N-terminal extension of indole-3-glycerol phosphate synthase (IGPS) by constructing more extensively truncated variants of (IGPS) from Sulfolobus solfataricus (sIGPS) and Thermotoga maritima. Their catalytic, and structural properties as well as their thermostabilities were discovered.

In all jaw-bearing vertebrates, three-dimensional mobility relies on segregated, separately innervated epaxial and hypaxial skeletal muscles. In amniotes, these muscles form from the morphologically continuous dermomyotome and myotome, whose epaxial-hypaxial subdivision and hence the formation of distinct epaxial-hypaxial muscles is not understood. Here we show that En1 expression labels a central subdomain of the avian dermomyotome, medially abutting the expression domain of the lead-lateral or hypaxial marker Sire1. En1 expression is maintained when cells from the En1-positive dermomyotome enter the myotome and dermatome, thereby superimposing the En1-Sim1 expression boundary onto the developing musculature and dermis. En1 cells originate from the dorsomedial edge of the somite. Their development is under positive control by notochord and floor plate (Shh), dorsal neural tube (Wnt1) and surface ectoderm (Wnt1-like signalling activity) but negatively regulated by the lateral plate mesoderm (BMP4). This dependence on epaxial signals and suppression by hypaxial signals places En1 into the epaxial somitic programme. Consequently, the En1-Sim1 expression boundary marks the epaxial-hypaxial dermomyotomal or myotomal boundary. In cell aggregation assays, En1- and Sim1-expressing cells sort out, suggesting that the En1-Sim1 expression boundary may represent a true compartment boundary, foreshadowing the epaxial-hypaxial segregation of muscle. Keywords: Chick embryo; Somite; Dermomyotome; Myotome; Dermatome; Skeletal muscle; Epaxial; Hypaxial; Horizontal myoseptum; Cell sorting; En1; Sim1; Alx4; Shh; Wnt; BMP4

The study shows that although myogenesis in the cranial paraxial mesoderm is induced by Wnt signals from the dorsal neural tube, myogenesis in the cranial paraxial mesoderm is blocked by these same signals. The findings suggest that Wnt and BMP signals locally repress head muscle formation, induced by antagonists of these signaling pathways secreted by adjacent tissues.

Removal of the terminal Pax-1 exon including the poly(A) signal leads to a 28.2 kb deletion in undulated extensive (un(ex)) mice, resulting in very low Pax-1 transcripts. Comparative phenotype analysis of un(ex), undulated short tail and undulated alleles indicates that the facial skeleton, verterbral column, scapula and sternum undergo morphological variations that are related to Pax-1 expression regions. Delayed cell accumulation in the embryonic sclerotome leads to reductions in the vertebral components.

Abstract Background Lbx/ladybird genes originated as part of the metazoan cluster of Nk homeobox genes. In all animals investigated so far, both the protostome genes and the vertebrate Lbx1 genes were found to play crucial roles in neural and muscle development. Recently however, additional Lbx genes with divergent expression patterns were discovered in amniotes. Early in the evolution of vertebrates, two rounds of whole genome duplication are thought to have occurred, during which 4 Lbx genes were generated. Which of these genes were maintained in extant vertebrates, and how these genes and their functions evolved, is not known. Results Here we searched vertebrate genomes for Lbx genes and discovered novel members of this gene family. We also identified signature genes linked to particular Lbx loci and traced the remnants of 4 Lbx paralogons (two of which retain Lbx genes) in amniotes. In teleosts, that have undergone an additional genome duplication, 8 Lbx paralogons (three of which retain Lbx genes) were found. Phylogenetic analyses of Lbx and Lbx-associated genes show that in extant, bony vertebrates only Lbx1- and Lbx2-type genes are maintained. Of these, some Lbx2 sequences evolved faster and were probably subject to neofunctionalisation, while Lbx1 genes may have retained more features of the ancestral Lbx gene. Genes at Lbx1 and former Lbx4 loci are more closely related, as are genes at Lbx2 and former Lbx3 loci. This suggests that during the second vertebrate genome duplication, Lbx1/4 and Lbx2/3 paralogons were generated from the duplicated Lbx loci created during the first duplication event. Conclusion Our study establishes for the first time the evolutionary history of Lbx genes in bony vertebrates, including the order of gene duplication events, gene loss and phylogenetic relationships. Moreover, we identified genetic hallmarks for each of the Lbx paralogons that can be used to trace Lbx genes as other vertebrate genomes become available. Significantly, we show that bony vertebrates only retained copies of Lbx1 and Lbx2 genes, with some Lbx2 genes being highly divergent. Thus, we have established a base on which the evolution of Lbx gene function in vertebrate development can be evaluated.