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Emotionally expressive faces have shown enhanced detectability over neutral faces, but little is known about the effect of eye gaze on detecting the presence of emotional faces. Emotional expressions and gaze direction are both cues to the intentions of another person, and gaze direction has been shown to affect recognition accuracy and perceived intensity of emotional faces. The current study showed that fearful faces were detected more frequently with an averted gaze than with a direct gaze in an attentional blink task, whereas angry and happy faces were detected more frequently with a direct gaze than with an averted gaze. The results are in line with the shared signal hypothesis and appraisal theory and suggest that selection for awareness was based on a rapid evaluation of the intentions of another person as conveyed by their facial expression and gaze direction., ((c) 2011 APA, all rights reserved.)

Objectives: To compare the temporal lobe white matter fiber bundles obtained by diffusion tensor imaging-based tractography to that by histology and dissection, and to study the interindividual variability of the obtained tracts., Materials and Methods: DTI (diffusion tensor imaging) acquisitions (30 directions) were obtained from nine healthy volunteers. Imaging post-processing was performed with FSL (FMRIB Software Library) software. Uncinate fasciculus, longitudinal inferior fasciculus and optic radiations were tracked after positioning of the region of interest (ROI) in predetermined anatomical landmarks. Histological data were obtained by cutting 15 µm coronal sections in one left brain hemisphere and staining with modified Heidenhain-Woelcke myelin stain. Dissection was performed on the left brain hemisphere prepared in accordance with the Klingler method. Tractography of each bundle was compared to histology and dissection data. To highlight the interindividual variability of the considered fiber tracts, all the images were affinely registered on an arbitrarily chosen reference image by considering the B0 images. Fiber tracts were then warped according to the corresponding estimated transformation and an average fiber tract image was then computed., Results: Our results demonstrated a good concordance between tractography of the temporal lobe white matter bundles and dissection and histological data. The interindividual reproducibility of each tract seemed to be good, particularly in the middle part. The variability was more important at both ends, probably in relation to the dispersion of fiber bundles., Conclusion: Diffusion tensor imaging-based tractography of temporal lobe white matter tracts seemed to be in accordance with histological and dissection data. Taking into account some limitations, it could be of particular interest for the presurgical planning of temporal lobectomy.

Brain imaging studies have revealed frontal disruption during aging and parieto-temporal disruption during Alzheimer's disease (AD). The present study aims at developing a specific method based on precise anatomical landmarks for assessing the integrity all along the course of the cingulum bundle, so as to determine if it presents the classical aging and AD dissociation. Five regions of interest (ROIs) were placed on fractional anisotropy (FA) maps all along the cingulum in 15 young (Gyoung), 15 70-year-old (Gold), and 15 AD subjects (Galz). An age-related decrease of FA occurred in the anterior part of the bundle. Moreover, a specific alteration of the supero-posterior region of the cingulum during AD was observed since mean FA values as well as mean number of fibers were significantly decreased in Galz compared to Gold and Gyoung. This multiple ROIs placement allows for revealing distinctive alterations of the cingulum bundle during aging and AD, which could constitute the anatomical basis for the distinctive functional disconnection recently described in the literature using functional connectivity at rest., (Copyright 2008 Elsevier Inc. All rights reserved.)

Colon interposition is the method of choice to restore the digestive tract after esogastrectomy. The aim of this study was to compare the length of the four available routes for colon transposition (posterior mediastinum route, transpleural route, substernal route and subcutaneous route) and to achieve a specific evaluation of the transpleural route. Our study was conducted with anatomical (dissection) and radiological (2D CT scan reconstructions) protocols. For both, the posterior mediastinum route was always the shortest way and the subcutaneous route was always the longest. For the anatomical results, the transpleural route and the substernal route were similar in terms of length and for the radiological study, the transpleural route was shorter than the substernal route (P < 0.001) and shorter than the subcutaneous route (P < 0.001). We demonstrated that the transpleural route was acceptable for colon transposition in term of length, and could be an alternative when the substernal route is unavailable.

With a cadaveric model, we studied the effects on the superior labrum-biceps tendon complex of a fall on the outstretched hand to assess one of the supposed mechanisms of creation of superior labrum anterior-posterior (SLAP) lesions. Ten shoulders were used to simulate either a forward or a backward fall with a custom shoulder-testing apparatus capable of simulating muscle forces, attached to a servohydraulic testing machine (INSTRON 8500+). Impaction of the humeral head on the glenoid cavity was applied in 0.1 seconds. The presence or absence of a SLAP lesion was determined. For the 5 shoulders used to simulate a forward fall, 5 type II SLAP lesions were found; for the 5 shoulders used to simulate a backward fall, only 2 type II SLAP lesions were observed. The role of shearing forces seems to be a major factor in the pathogenesis of these lesions, in association with predisposing anatomic factors.

Medical training is undergoing extensive revision in France. A nationwide comprehensive clinical competency examination will be administered for the first time in 2004, relying exclusively on essay-questions. Unfortunately, these questions have psychometric shortcomings, particularly their typically low reliability. High score reliability is mandatory in a high-stakes context. The National Board of Medical Examiners-designed multiple choice-questions (MCQ) are well adapted to assess clinical competency with a high reliability score. The purpose of this study was to test the hypothesis that French medical students could take an American-designed and French-adapted comprehensive clinical knowledge examination with this MCQ format. Two hundred and eighty five French students, from four Medical Schools across France, took an examination composed of 200 MCQs under standardized conditions. Their scores were compared with those of American students. This examination was found assess French students' clinical knowledge with a high level of reliability. French students' scores were slightly lower than those of American students, mostly due to a lack of familiarity with this particular item format, and a lower motivational level. Another study is being designed, with a larger group, to address some of the shortcomings of the initial study. If these preliminary results are replicated, the MCQ format might be a more defendable and sensible alternative to the proposed essay questions.

This paper presents a comprehensive comparative analysis of the Neanderthal bony labyrinth, a structure located inside the petrous temporal bone. Fifteen Neanderthal specimens are compared with a Holocene human sample, as well as with a small number of European Middle Pleistocene hominins, and early anatomically modern and European Upper Palaeolithic humans. Compared with Holocene humans the bony labyrinth of Neanderthals can be characterized by an anterior semicircular canal arc which is smaller in absolute and relative size, is relatively narrow, and shows more torsion. The posterior semicircular canal arc is smaller in absolute and relative size as well, it is more circular in shape, and is positioned more inferiorly relative to the lateral canal plane. The lateral semicircular canal arc is absolutely and relatively larger. Finally, the Neanderthal ampullar line is more vertically inclined relative to the planar orientation of the lateral canal. The European Upper Palaeolithic and early modern humans are most similar, although not fully identical to Holocene humans in labyrinthine morphology. The European Middle Pleistocene hominins show the typical semicircular canal morphology of Neanderthals, with the exception of the arc shape and inferiorly position of the posterior canal and the strongly inclined ampullar line. The marked difference between the labyrinths of Neanderthals and modern humans can be used to assess the phylogenetic affinities of fragmentary temporal bone fossils. However, this application is limited by a degree of overlap between the morphologies. The typical shape of the Neanderthal labyrinth appears to mirror aspects of the surrounding petrous pyramid, and both may follow from the phylogenetic impact of Neanderthal brain morphology moulding the shape of the posterior cranial fossa. The functionally important arc sizes of the Neanderthal semicircular canals may reflect a pattern of head movements different from that of modern humans, possibly related to aspects of locomotor behaviour and the kinematic properties of their head and neck.