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To date, there is no functional account of the visual perception of gaze in humans. Previous work has demonstrated that left gaze and right gaze are represented by separate mechanisms. However, these data are consistent with either a multichannel system comprising separate channels for distinct gaze directions (e.g., left, direct, and right) or an opponent-coding system in which all gaze directions are coded by just 2 pools of cells, one coding left gaze and the other right, with direct gaze represented as a neutral point reflecting equal activation of both left and right pools. In 2 experiments, the authors used adaptation procedures to investigate which of these models provides the optimal account. Both experiments supported multichannel coding. Previous research has shown that facial identity is coded by an opponent-coding system; hence, these results also demonstrate that gaze is coded by a different representational system to facial identity. [ABSTRACT FROM AUTHOR]

The "behavioral approach system" (BAS) (Gray, 1990) has been primarily associated with reward processing and positive affect. However, additional research has demonstrated that the BAS plays a role in aggressive behavior, heightened experience of anger, and increased attention to facial signals of aggression. Using functional magnetic resonance imaging, we show that variation in the BAS trait in healthy participants predicts activation in neural regions implicated in aggression when participants view facial signals of aggression in others. Increased BAS drive (appetitive motivation) was associated with increased amygdala activation and decreased ventral anterior cingulate and ventral striatal activation to facial signals of aggression, relative to sad and neutral expressions. In contrast, increased behavioral inhibition was associated with increased activation in the dorsal anterior cingulate, a region involved in the perception of fear and threat. Our results provide the first demonstration that appetitive motivation constitutes a significant factor governing the function of neural regions implicated in aggression, and have implications for understanding clinical disorders of aggression. [ABSTRACT FROM AUTHOR]

Abstract: Pulvinar activation has been observed while viewing fearful expressions, but the necessity of this activation to their recognition has not been previously assessed. We measured the processing of emotional facial expressions in a rare patient with complete unilateral loss of the pulvinar. With brief presentations, patient CJ was incapable of recognizing fearful expressions in his contralesional field. Three other patients, with damage limited to the anterior and to the lateral pulvinar, showed no deficits in recognition. In conjunction with anatomical studies of the monkey pulvinar, these results suggest that fear recognition is mediated by the human medial pulvinar. We outline the possible role of the pulvinar in fear recognition, considering both the pulvinar''s direct and indirect cortical connections with the amygdala, and we suggest that the integrative role of the pulvinar may be primary. Our results suggest that the cortex in isolation from the entire pulvinar is incapable of recognizing fearful expressions. [Copyright &y& Elsevier]

The anterior insula has been implicated in coding disgust from facial, pictorial and olfactory cues, and in the experience of this emotion. Personality research has shown considerable variation in individuals' trait propensity to experience disgust (‘disgust sensitivity’). Our study explored the neural expression of this trait, and demonstrates that individual variation in disgust sensitivity is significantly correlated with participants' ventroanterior insular response to viewing pictures of disgusting, but not appetizing or bland, foods. Similar correlations were also seen in the pallidum and orofacial regions of motor and somatosensory cortices. Our results also accord with comparative research showing an anterior to posterior gradient in the rat pallidum reflecting increased ‘liking’ of foods [Smith, K. S. and Berridge, K. C. (2005) J. Neurosci., 25, 849–8637]. [ABSTRACT FROM AUTHOR]

A network of interconnected brain regions, including orbitofrontal, ventral striatal, amygdala, and midbrain areas, has been widely implicated in a number of aspects of food reward. However, in humans, sensitivity to reward can vary significantly from one person to the next. Individuals high in this trait experience more frequent and intense food cravings and are more likely to be overweight or develop eating disorders associated with excessive food intake. Using functional magnetic resonance imaging, we report that individual variation in trait reward sensitivity (as measured by the Behavioral Activation Scale) is highly correlated with activation to images of appetizing foods (e.g., chocolate cake, pizza) in a fronto-striatal-amygdala-midbrain network. Our findings demonstrate that there is considerable personality-linked variability in the neural response to food cues in healthy participants and provide important insight into the neurobiological factors underlying vulnerability to certain eating problems (e.g., hyperphagic obesity). [ABSTRACT FROM AUTHOR]

Objective: Control of cervical function is poorly understood. The major structural component of the cervix is collagen and peri-partum cervical changes are largely due to the action of collagenase, either released by resident cells or derived from an influx of neutrophils. More importantly, the cell type that initiates the changes in the cervix is unknown although the resident fibroblast is a possible contender. Little is known about the state of the cervical fibroblast during pregnancy. Decidualisation of the endometrium is essential for implantation and pregnancy. In man, pre-decidual and decidual transformation of endometrial stroma occurs under the influence of progesterone. Decidualisation can also be induced in vitro in endometrial fibroblast-like stromal cells where the process is also dependent on elevated intracellular cAMP levels. Study design: Cultured human cervical fibroblasts were treated with progestin (medroxyprogesterone acetate) and cAMP elevating agents for 6 and 10 days. Results: After 6 days they expressed and released IGFBP-1 and prolactin (PRL) and underwent morphological changes by 10 days. In addition, there was an increase in progesterone receptor and prostaglandin E type 2 receptor mRNA (but not type 4). Conclusion: The propensity of cervical stromal cells to decidualise suggests that these differentiated cells may be a better model with which to study the initiation of labour. [Copyright &y& Elsevier]

OBJECTIVE — In adults, adiponectin is reduced in association with excess adiposity, type 2 diabetes, and hyperinsulinemia. We assessed whether adiponectin was 1) present in the fetal circulation, 2) altered in the fetal circulation in the presence of maternal diabetes, and 3) had relations to fetal cord blood insulin or adiposity. RESEARCH DESIGN AND METHODS — We assessed adiponectin in cord blood in a large cohort of singleton offspring of diabetic mothers (ODM; n = 134) and control mothers (n = 45). RESULTS — Adiponectin was present in cord blood and, in ODM, was higher in those delivered at later gestational ages (Spearman r = 0.18, P = 0.03). Adiponectin was slightly lower in ODM than control subjects (ODM 19.7 ± 6.1 vs. control 21.8 ± 5.3 µg/ml; P = 0.04), although this difference could potentially reflect different gestational ages in the two groups (ODM 37.6 ± 1.5 and control 40.1 ± 1.1 weeks). In contrast to adults, adiponectin levels in the fetus were unrelated to the degree of adiposity, blood insulin, or leptin in either control subjects or ODM. CONCLUSIONS — Adiponectin is present in cord blood but does not show expected physiological relations with adiposity as observed in adults. [ABSTRACT FROM AUTHOR]

We report three experiments investigating the recognition of emotion from facial expressions across the adult life span. Increasing age produced a progressive reduction in the recognition of fear and, to a lesser extent, anger. In contrast, older participants showed no reduction in recognition of disgust, rather there was some evidence of an improvement. The results are discussed in terms of studies from the neuropsychological and functional imaging literature that indicate that separate brain regions may underlie the emotions fear and disgust. We suggest that the dissociable effects found for fear and disgust are consistent with the differential effects of ageing on brain regions involved in these emotions. [Copyright &y& Elsevier]

Baron-Cohen [Mindblindness: an essay on autism and theory of mind. Cambridge, MA: MIT Press, 1997] has suggested that the interpretation of gaze plays an important role in a normal functioning theory of mind (ToM) system. Consistent with this suggestion, functional imaging research has shown that both ToM tasks and eye gaze processing engage a similar region of the posterior superior temporal sulcus (STS). However, a second brain region associated with ToM, the medial prefrontal (MPF) cortex, has not been identified by previous eye gaze studies. We discuss the methodological issues that may account for the absence of MPF activation in these experiments and present a PET study that controls for these factors. Our experiment included three conditions in which the proportions of faces gazing at, and away from, the participant, were as follows: 100% direct [0% averted], 50% direct—50% averted, and 100% horizontally averted [0% direct]. Two control conditions were also included in which the faces’ gaze were averted down, or their eyes were closed. Contrasts comparing the gaze conditions with each of the control conditions revealed medial frontal involvement. Parametric analyses showed a significant linear relationship between increasing proportions of horizontally averted gaze and increased rCBF in the MPF cortex. The opposite parametric analysis (increasing proportions of direct gaze) was associated with increased rCBF in a number of areas including the superior and medial temporal gyri. Additional subtraction contrasts largely confirmed these patterns. Our results demonstrate a considerable degree of overlap between the medial frontal areas involved in eye gaze processing and theory of mind tasks. [Copyright &y& Elsevier]

Lavenu et al. [Alzheimer Dis. Assoc. Disorder 5 (1999) 96] have shown that patients with frontotemporal dementia (FTD) show impaired recognition of facial expressions. It is not clear, however, whether these deficits arise from an impairment affecting face processing generally, emotion processing generally, or facial expression recognition alone. We address this issue by testing six patients with frontal variant frontotemporal dementia (fvFTD) on a series of face perception tasks (including facial identity and facial expression recognition), and a test of vocal emotion recognition. In general, the fvFTD participants showed impaired recognition of facial expressions in the context of preserved recognition of facial identity. In addition, however, deficits were also observed for the vocal emotion recognition task. These results are consistent with the idea that fvFTD affects the recognition of emotional signals from multiple modalities rather than facial expression processing alone. It is plausible that the emotion recognition impairments observed contribute to the abnormal social behaviour that is characteristic of this condition. [Copyright &y& Elsevier]

Examines the perceptual representation of facial expressions. Role of configural information in facial expression recognition; Parallelism between the composite effects for facial identity and for facial expression; Nature of encoding of configural information during facial identity and facial expression processing.

Purpose Previous studies have reported changes in gray matter volume in youths with conduct disorder (CD), although these differences are difficult to interpret as they may have been driven by alterations in cortical thickness, surface area (SA), or folding. The objective of this study was to use surface-based morphometry (SBM) methods to compare male youths with CD and age and sex-matched healthy controls (HCs) in cortical thickness, SA, and folding. We also tested for structural differences between the childhood-onset and adolescence-onset subtypes of CD and performed regression analyses to assess for relationships between CD symptoms and callous–unemotional (CU) traits and SBM-derived measures. Methods: We acquired structural neuroimaging data from 20 HCs and 36 CD participants (18 with childhood-onset CD and 18 with adolescence-onset CD) and analyzed the data using FreeSurfer. Results: Relative to HCs, youths with CD showed reduced cortical thickness in the superior temporal gyrus, reduced SA in the orbitofrontal cortex (OFC), and increased cortical folding in the insula. There were no significant differences between the childhood-onset and adolescence-onset CD subgroups in cortical thickness or SA, but several frontal and temporal regions showed increased cortical folding in childhood-onset relative to adolescence-onset CD participants. Both CD subgroups also showed increased cortical folding relative to HCs. CD symptoms were negatively correlated with OFC SA whereas CU traits were positively correlated with insula folding. Conclusions: Cortical thinning in the superior temporal gyrus may contribute to the social cognitive impairments displayed by youths with CD, whereas reduced OFC SA may lead to impairments in emotion regulation and reward processing in youths with CD. The increased cortical folding observed in the insula may reflect a maturational delay in this region and could mediate the link between CU traits and empathy deficits. Altered cortical folding was observed in childhood-onset and adolescence-onset forms of CD.

Presents a study of the cervical biopsy specimens fron nonpregnant women to investigate the regulation of inflammatory mediators implicated in cervical ripening. Stimulation of the cervical explants by prostaglandin and nitric oxide; Effect of progesterone and dexamethasone; Complexity of interactions between inflammatory cytokines within the cervix.

Human seminal plasma has potent anti-inflammatory properties which are thought to confer a survival advantage to the spermatozoa within the hostile female genital tract. In contrast, a profound pro-inflammatory leukocytosis has been observed post-coitus in animals and humans. Whether components of seminal plasma are involved in initiating this leukocytic reaction is not known. This study investigated the effect of human seminal plasma, a seminal plasma fraction and its principal constituent prostaglandins, prostaglandin E2 (PGE2) and 19-hydroxy PGE, on the release of the pro-inflammatory neutrophil chemotactic factor interleukin-8 (IL-8) and the anti-inflammatory cytokines interleukin-10 (IL-10) and secretory leukocyte protease inhibitor (SLPI). The tissues studied were non-pregnant cervical explants, peripheral blood and the monocyte cell line U937. Seminal plasma fraction (SPF) significantly (P < 0.05) stimulated release of IL-8 and inhibited release of SLPI from non-pregnant cervical explants. SPF, PGE2 and 19-hydroxy PGE significantly (P < 0.005) stimulated IL-8 release from peripheral blood and U937 cells. 19-hydroxy PGE was significantly (P < 0.005) more effective than PGE2 in stimulating IL-8 release. Seminal plasma, SPF and PGE2 significantly (P < 0.05) stimulated IL-10 release from U937 cells. 19-hydroxy PGE stimulated IL-10 release from U937 cells but this failed to reach significance. Release of IL-10 by cervical explants and SLPI by peripheral blood and U937 cells were below the detection limit of the assays employed. We suggest that the anti- and pro-inflammatory immune responses which seminal plasma induces might act in combination initially to promote sperm survival and then to facilitate their removal from the female genital tract. [ABSTRACT FROM PUBLISHER]

Matrix metalloproteinases (MMPs) are important enzymes in tissue remodelling, a key event for the development of the fetal membranes and placenta and establishing the feto–maternal interface during early pregnancy. This study has examined the secretion of the gelatinases, MMP-2 (72 kDa) and MMP-9 (92 kDa), and the endogenous tissue inhibitors of metalloproteinases (TIMPs) into extra-embryonic coelomic and amniotic fluids, the two principal intra-uterine compartments of the first trimester, and compared them to amniotic fluid collected later in gestation. In extra-embryonic coelomic fluid, gelatin zymography demonstrated that MMP-2 (72 kDa) was the predominant gelatinase, with some MMP-9 present. A broad range of TIMPs corresponding to TIMP-1 and TIMP-2, glycosylated and unglycosylated TIMP-3 and TIMP-4 was detected in this compartment by reverse zymography and immunoblot analyses. There was little gelatinase or TIMP activity in amniotic fluid in the first trimester. In amniotic fluid from the second trimester after fusion of the membranes obliterating the extra-embryonic coelom, and at term elective caesarean section, MMP-2 is the predominant gelatinase present, with a broad spectrum of TIMPs. These findings demonstrate that predominantly MMP-2 and also MMP-9, regulated by a range of TIMPs, are involved in intra-uterine tissue remodelling during the establishment of pregnancy. [ABSTRACT FROM AUTHOR]

Discusses self priming from distinctive and caricatured faces in psychology. Interactive activation and competition model of face recognition; Repetition priming; Semantic priming; Distinctiveness effects with faces.

Objective: Our purpose was to assess the effects of labor and antigestagens on production of interleukin 8 by the term human placenta and to localize interleukin 8 in first- and third- trimester placentas.Study Design: The study was conducted by the Department of Obstetrics and Gynaecology of the University of Edinburgh. Five placentas were collected after spontaneous and cesarean deliveries. Explants were cultured in the presence of mifepristone, lilopristone, or onapristone. The production of interleukin 8 was determined by specific radioimmunoassay, and the immunolocalization of interleukin 8 was determined in sections of first- and third-trimester placentas.Results: All explants produced interleukin 8. Production was significantly increased (P < .05) after spontaneous delivery. In placentas delivered spontaneously, onapristone significantly increased production of interleukin 8 (P < .05), whereas in those from cesarean deliveries lilopristone caused a significant increase in production (P < .05). In the third-trimester placenta interleukin 8 was localized in the perivascular area of fetal vessels. In first-trimester villi it was peripherally located in syncytiotrophoblast.Conclusion: The human placenta at term is capable of producing interleukin 8, which is localized around the perivascular area of the villi. Production is increased after spontaneous labor and to varying degrees by the antigestagens studied. Interleukin 8 may have a role in the onset of parturition by recruiting and activating neutrophils at the placental site. [ABSTRACT FROM AUTHOR]

The genus Crepicardus is endemic to Madagascar. Ten species are here recognized and redescribed; a key for their identification is given. The genus falls into three distinct species groups and one unassigned species: the klugii-group ( klugii Castelnau, madagscariensis Fleutiaux, cribricollis Fleutiaux), the candezei-group ( candezei Fairmaire stat.rev., raffrayi Fairmaire, niger Candèze, puncticollis Fleutiaux), the trisulcatus-group ( trisulcatus Candèze, mocquerysi Fleutiaux) and fleutiauxi Girard. Crepicardus costicollis (Castelnau) is again placed as a junior synonym of C.klugii (Castelnau) and candezei Fairmaire restored to specific status. Lectotypes are designated for klugii Castelnau, costicollis Castelnau, candezei Fairmaire, raffrayi Fairmaire, niger Candèze and mocquerysi Fleutiaux. On the basis of adult characters Crepicardus is here assigned to the Pyrophorinae sensu Stibick (1979) and its systematic position is discussed in relation to the widespread Pyrophorinae. [ABSTRACT FROM AUTHOR]

Four species of the genus Anaissus Candeze are recognized and described or redescribed and a key for their identification is given; anandra sp.n., aurantium spn., fuscipes sp.n. and tarsalis Candeze (= spinipennis syn.n.). A new subgenus Auctumnalis is erected with aurantium as type-species. Two possible species from Brazil and French Guiana respectively are also reported. The systematic position of the genus is discussed in relation to the Neotropical Pyrophorinae, and on the basis of adult characters Anaissus is here assigned to the subfamily Pyrophorinae. [ABSTRACT FROM AUTHOR]

Research suggests that although a high proportion of patients accept the presence of students in gynaecological consultations, issues of consent, privacy and comfort are important. This study considers women's views on the impact of student presence on communication in the consultation. Our research suggests that student presence may distort the flow of communication in the gynaecological consultation. There are implications for both patient satisfaction and clinician training. If students are introduced into the consultation, clinical tutors should take special care to maintain dedicated communication with the patient. [ABSTRACT FROM AUTHOR]

Neural activity cannot be directly observed using fMRI; rather it must be inferred from the hemodynamic responses that neural activity causes. Solving this inverse problem is made possible through the use of forward models, which generate predicted hemodynamic responses given hypothesised underlying neural activity. Commonly‐used hemodynamic models were developed to explain data from healthy young participants; however, studies of ageing and dementia are increasingly shifting the focus toward elderly populations. We evaluated the validity of a range of hemodynamic models across the healthy adult lifespan: from basis sets for the linear convolution models commonly used to analyse fMRI studies, to more advanced models including nonlinear fitting of a parameterised hemodynamic response function (HRF) and nonlinear fitting of a biophysical generative model (hemodynamic modelling, HDM). Using an exceptionally large sample of participants, and a sensorimotor task optimized for detecting the shape of the BOLD response to brief stimulation, we first characterised the effects of age on descriptive features of the response (e.g., peak amplitude and latency). We then compared these to features from more complex nonlinear models, fit to four regions of interest engaged by the task, namely left auditory cortex, bilateral visual cortex, left (contralateral) motor cortex and right (ipsilateral) motor cortex. Finally, we validated the extent to which parameter estimates from these models have predictive validity, in terms of how well they predict age in cross‐validated multiple regression. We conclude that age‐related differences in the BOLD response can be captured effectively by models with three free parameters. Furthermore, we show that biophysical models like the HDM have predictive validity comparable to more common models, while additionally providing insights into underlying mechanisms, which go beyond descriptive features like peak amplitude or latency, and include estimation of nonlinear effects. Here, the HDM revealed that most of the effects of age on the BOLD response could be explained by an increased rate of vasoactive signal decay and decreased transit rate of blood, rather than changes in neural activity per se. However, in the absence of other types of neural/hemodynamic data, unique interpretation of HDM parameters is difficult from fMRI data alone, and some brain regions in some tasks (e.g., ipsilateral motor cortex) can show responses that are more difficult to capture using current models. [ABSTRACT FROM AUTHOR]