Facial affect recognition training in autism: can we animate the fusiform gyrus?

One of the most consistent findings in the neuroscience of autism is hypoactivation of the fusiform gyrus (FG) during face processing. In this study the authors examined whether successful facial affect recognition training is associated with an increased activation of the FG in autism. The effect of a computer-based program to teach facial affect identification was examined in 10 individuals with high-functioning autism. Blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) changes in the FG and other regions of interest, as well as behavioral facial affect recognition measures, were assessed pre- and posttraining. No significant activation changes in the FG were observed. Trained participants showed behavioral improvements, which were accompanied by higher BOLD fMRI signals in the superior parietal lobule and maintained activation in the right medial occipital gyrus.

The development and evaluation of a computer-based program to test and to teach the recognition of facial affect

Autism is a chronic pervasive neurodevelopmental disorder characterized by the early onset of social and communicative impairments as well as restricted, ritualized, stereotypic behavior. The endophenotype of autism includes neuropsychological deficits, for instance a lack of "Theory of Mind" and problems recognizing facial affect. In this study, we report the development and evaluation of a computer-based program to teach and test the ability to identify basic facially expressed emotions. 10 adolescent or adult subjects with high-functioning autism or Asperger-syndrome were included in the investigation. A priori the facial affect recognition test had shown good psychometric properties in a normative sample (internal consistency: rtt=.91-.95; retest reliability: rtt=.89-.92). In a prepost design, one half of the sample was randomly assigned to receive computer treatment while the other half of the sample served as control group. The training was conducted for five weeks, consisting of two hours training a week. The trained individuals improved significantly on the affect recognition task, but not on any other measure. Results support the usefulness of the program to teach the detection of facial affect. However, the improvement found is limited to a circumscribed area of social-communicative function and generalization is not ensured.

A new system for computer-aided preoperative planning and intraoperative navigation during corrective jaw surgery

A new system for computer-aided corrective surgery of the jaws has been developed and introduced clinically. It combines three-dimensional (3-D) surgical planning with conventional dental occlusion planning. The developed software allows simulating the surgical correction on virtual 3-D models of the facial skeleton generated from computed tomography (CT) scans. Surgery planning and simulation include dynamic cephalometry, semi-automatic mirroring, interactive cutting of bone and segment repositioning. By coupling the software with a tracking system and with the help of a special registration procedure, we are able to acquire dental occlusion plans from plaster model mounts. Upon completion of the surgical plan, the setup is used to manufacture positioning splints for intraoperative guidance. The system provides further intraoperative assistance with the help of a display showing jaw positions and 3-D positioning guides updated in real time during the surgical procedure. The proposed approach offers the advantages of 3-D visualization and tracking technology without sacrificing long-proven cast-based techniques for dental occlusion evaluation. The system has been applied on one patient. Throughout this procedure, we have experienced improved assessment of pathology, increased precision, and augmented control.

Parallel evolution of facial stripe patterns in the Neolamprologus brichardilpulcher species complex endemic to Lake Tanganyika

Colour pattern diversity can be due to random processes or to natural or sexual selection. Consequently, similarities in colour patterns are not always correlated with common ancestry, but may result from convergent evolution under shared selection pressures or drift. Neolamprologus brichardi and Neolamprologus pulcher have been described as two distinct species based on differences in the arrangement of two dark bars on the operculum. Our study uses DNA sequences of the mitochondrial control region to show that relatedness of haplotypes disagrees with species assignment based on head colour pattern. This suggests repeated parallel evolution of particular stripe patterns. The complete lack of shared haplotypes between populations of the same or different phenotypes reflects strong philopatric behaviour, possibly induced by the cooperative breeding mode in which offspring remain in their natal territory and serve as helpers until they disperse to nearby territories or take over a breeding position. Concordant phylogeographic patterns between N. brichardi/N. pulcher populations and other rock-dwelling cichlids suggest that the same colonization routes have been taken by sympatric species and that these routes were affected by lake level fluctuations in the past. (C) 2007 Elsevier Inc. All rights reserved.

Assessment of vertical facial and dentoalveolar changes using panoramic radiography

The purpose of the study was to analyse longitudinal vertical facial and dentoalveolar changes using panoramic radiographs (PRs) and to compare the results with measurements on lateral cephalometric radiographs (LCRs) in order to determine whether, under certain circumstances, the radiation dose for a patient may be reduced by taking only a PR instead of a PR and a LCR. Pre- and post-treatment PRs and LCRs of 30 (15 females and 15 males) orthodontically treated adolescents (mean age pre-treatment 10.9 years, post-treatment 13.4 years) were analysed using Pearson's correlation coefficients and gender differences using Fisher's z-transformation. The results revealed that most variables exhibited larger absolute values on PRs than on LCRs. Comparison of dentoskeletal morphology between the LCRs and the PRs revealed moderate to high, mostly statistically significant, interrelations both before and after orthodontic treatment. The lowest correlations were found for the maxillary jaw base angle (NL/H; r= 0.35***) and the highest for the gonial angle (ML/RL; r = 0.90***). However, when assessing the combined growth and treatment changes from before to after treatment, only weak to moderate, not statistically significant, interrelations were found between LCRs and PRs. Anterior face height (AFH; r = 0.43***), the mandibular plane angle (ML/H; r = 0.06*), and the distance of the incisal tip of the most extruded mandibular incisor to the ML-line (ii-ML; r = -0.21*) were the only statistically significant parameters. The average group differences for growth and treatment changes, however, were small for most parameters. Analysis of vertical facial and dentoalveolar parameters on PRs delivers a moderate approximation to the situation depicted on LCRs. However, PRs cannot be recommended for the analysis of individual longitudinal changes in vertical facial and dentoalveolar parameters.

Diel variation in a dynamic sexual display and its association with female mate-searching behaviour

Dynamic sexual signals often show a diel rhythm and may vary substantially with time of day. Diel and short-term fluctuations in such sexual signals pose a puzzle for condition capture models of mate choice, which assume a female preference for male traits that reliably reflect a male's quality. Here we experimentally manipulated the food supply of individual male field crickets Gryllus campestris in their natural habitat in two consecutive seasons to determine (i) the effect of male nutritional condition on the fine-scaled variation of diel investment in acoustic signalling and (ii) the temporal association between the diel variation in male signalling and female mate-searching behaviour. Overall food-supplemented males signalled more often, but the effect was only visible during the daytime. In the evening and the night, signal output was still high but the time spent signalling was unrelated to a male's nutritional condition. Females' mate-searching behaviour also showed a diel rhythm with peak activity during the afternoon, when differences among calling males were highest, and where signal output reliably reflects male quality. These findings suggest that males differing in nutritional condition may optimize their investment in signalling in relation to time of day as to maximize mating success.

Simple virtual reality display of fetal volume ultrasound

Three-dimensional (3D) ultrasound volume acquisition, analysis and display of fetal structures have enhanced their visualization and greatly improved the general understanding of their anatomy and pathology. The dynamic display of volume data generally depends on proprietary software, usually supplied with the ultrasound system, and on the operator's ability to maneuver the dataset digitally. We have used relatively simple tools and an established storage, display and manipulation format to generate non-linear virtual reality object movies of prenatal images (including moving sequences and 3D-rendered views) that can be navigated easily and interactively on any current computer. This approach permits a viewing or learning experience that is superior to watching a linear movie passively.

Pediatric cranio-facial surgery. First-year's experience with a gun applying bioabsorbable tacks

AIM: In 2001 a prototype of a gun to apply bioabsorbable tacks in cranio-facial surgery has been developed. METHODS: From May 2001 to May 2002 this device has been used in the University Hospital of Innsbruck (Austria) for different cranioplasty procedures, in 34 children, showing its reliability for cranio-facial bone fixation. The children were affected by isolated craniosynostosis or by syndromical synostosis (Apert, Crouzon) and in a case of benign tumor of the parietal skull vault. The range of age, at the time of surgery, was between 3 months and 204 months of age. Bone segments were fixed using self-reinforced polylactide plates and tacks. RESULTS: Firm fixation was obtained intra-operatively and the operative time was reduced about 25-30 minutes as compared to use of plates and screws. This device has just one limitation in its own spring force: sometimes the bone thinner than 1 mm has been broken applying the tacks. CONCLUSION: After the first-year's experience it is possible to confirm that this device reduces, in selected cases, operative time, blood loss, risk of infection and, as a result, the costs.

Changing trends in causes and patterns of facial fractures in children

OBJECTIVE: To review the epidemiology of facial fractures in children and to analyze whether it has changed over time. STUDY DESIGN: Retrospective review of records of children aged < or = 15 years diagnosed for fracture during 2 10-year periods. RESULTS: A total of 378 children were diagnosed with fractures, 187 in 1980-1989 and 191 in 1993-2002. The proportion of children with mandibular fractures decreased by 13.6 percentage-points from the first period to the second, whereas the proportion of patients with midfacial fractures increased by 18.7 percentage-points. Assault as a causative factor increased by 5.5 percentage-points, almost exclusively among children aged 13-15 years, with a high percentage (23.5%). CONCLUSIONS: Recognition of a change in fracture patterns over time is probably due to the increased use of computerized tomographic scanning.

Uncrossed cortico-muscular projections in humans are abundant to facial muscles of the upper and lower face, but may differ between sexes

It is a popular concept in clinical neurology that muscles of the lower face receive predominantly crossed cortico-bulbar motor input, whereas muscles of the upper face receive additional ipsilateral, uncrossed input. To test this notion, we used focal transcranial magnetic brain stimulation to quantify crossed and uncrossed cortico-muscular projections to 6 different facial muscles (right and left Mm. frontalis, nasalis, and orbicularis oris) in 36 healthy right-handed volunteers (15 men, 21 women, mean age 25 years). Uncrossed input was present in 78% to 92% of the 6 examined muscles. The mean uncrossed: crossed response amplitude ratios were 0.74/0.65 in right/left frontalis, 0.73/0.59 in nasalis, and 0.54/0.71 in orbicularis oris; ANOVA p>0.05). Judged by the sizes of motor evoked potentials, the cortical representation of the 3 muscles was similar. The amount of uncrossed projections was different between men and women, since men had stronger left-to-left projections and women stronger right-to-right projections. We conclude that the amount of uncrossed pyramidal projections is not different for muscles of the upper from those of the lower face. The clinical observation that frontal muscles are often spared in central facial palsies must, therefore, be explained differently. Moreover, gender specific lateralization phenomena may not only be present for higher level behavioural functions, but may also affect simple systems on a lower level of motor hierarchy.

Pollinator responses to variation in floral display and flower size in dioecious Sagittaria latifolia (Alismataceae)

In animal-pollinated plants with unisexual flowers, sexual dimorphism in floral traits may be the consequence of pollinator-mediated selection. Experimental investigations of the effects of variation in flower size and floral display on pollinator visitation can provide insights into the evolution of floral dimorphism in dioecious plants. Here, we investigated pollinator responses to experimental arrays of dioecious Sagittaria latifolia in which we manipulated floral display and flower size. We also examined whether there were changes in pollinator visitation with increasing dimorphism in flower size. In S. latifolia, males have larger flowers and smaller floral displays than females. Visitation by pollinators, mainly flies and bees, was more frequent for male than for female inflorescences and increased with increasing flower size, regardless of sex. The number of insect visits per flower decreased with increasing floral display in males but remained constant in females. Greater sexual dimorphism in flower size increased visits to male inflorescences but had no influence on the number of visits to female inflorescences. These results suggest that larger flower sizes would be advantageous to both females and males, and no evidence was found that females suffer from increased flower-size dimorphism. Small daily floral displays may benefit males by allowing extended flowering periods and greater opportunities for effective pollen dispersal.

Engineered fibrin matrices for functional display of cell membrane-bound growth factor-like activities: study of angiogenic signaling by ephrin-B2

With the rapid increase in approaches to pro- or anti-angiogenic therapy, new and effective methodologies for administration of cell-bound growth factors will be required. We sought to develop the natural hydrogel matrix fibrin as platform for extensive interactions and continuous signaling by the vascular morphogen ephrin-B2 that normally resides in the plasma membrane and requires multivalent presentation for ligation and activation of Eph receptors on apposing endothelial cell surfaces. Using fibrin and protein engineering technology to induce multivalent ligand presentation, a recombinant mutant ephrin-B2 receptor binding domain was covalently coupled to fibrin networks at variably high densities. The ability of fibrin-bound ephrin-B2 to act as ligand for endothelial cells was preserved, as demonstrated by a concomitant, dose-dependent increase of endothelial cell binding to engineered ephrin-B2-fibrin substrates in vitro. The therapeutic relevance of ephrin-B2-fibrin implant matrices was demonstrated by a local angiogenic response in the chick embryo chorioallontoic membrane evoked by the local and prolonged presentation of matrix-bound ephrin-B2 to tissue adjacing the implant. This new knowledge on biomimetic fibrin vehicles for precise local delivery of membrane-bound growth factor signals may help to elucidate specific biological growth factor function, and serve as starting point for development of new treatment strategies.