Assessment of body image in obesity using a digital morphing technique.

BACKGROUND: Historically, body image research has relied on generic, whole body outlines, which may not be suited to obese individuals. The development of computer generated, individualized digital images to represent body image may be more effective. METHODS: Sixty volunteers participated, with three categories of subject: lean, obese and lean regular exercisers. Body image was assessed using a digital morphing technique in comparison to two standard paper questionnaires. RESULTS: Using the novel digital morphing tool, obese subjects displayed poorer body awareness (perception) than their lean counterparts (P = 0.03), significantly over-estimating their actual body size. Both genders overestimated body size to a similar degree. For body satisfaction, females wished to be smaller and males to be larger, identifying gender-specific body regions (P < 0.001). Obese subjects showed greatest dissatisfaction (P < 0.001) with body image. There was significant correlation for body image dissatisfaction (P < 0.05) between the digital technique and the questionnaires, which was highest for the figural stimuli questionnaire (r = 0.80, P < 0.001). CONCLUSIONS: This method represents a novel and alternative approach to rating body image perception (IP) and satisfaction in obese subjects, particularly providing data on specific regional areas. Body image dissatisfaction appears to be both due to poor body IP compounded with the desire to be smaller.

Neural responses to dynamic expressions of fear in schizophrenia.

Abnormalities in social functioning are a significant feature of schizophrenia. One critical aspect of these abnormalities is the difficulty these individuals have with the recognition of facial emotions, particularly negative expressions such as fear. The present work focuses on fear perception and its relationship to the paranoid symptoms of schizophrenia, specifically, how underlying limbic system structures (i.e. the amygdala) react when probed with dynamic fearful facial expressions. Seven paranoid and eight non-paranoid subjects (all males) with a diagnosis of schizophrenia took part in functional magnetic resonance imaging study (1.5T) examining neural responses to emerging fearful expressions contrasted with dissipating fearful expressions. Subjects viewed emerging and dissipating expressions while completing a gender discrimination task. Their brain activation was compared to that of 10 healthy male subjects. Increased hippocampal activation was seen in the non-paranoid group, while abnormalities in the bilateral amygdalae were observed only in the paranoid individuals. These patterns may represent trait-related hippocampal dysfunction, coupled with state (specifically paranoia) related amygdala abnormalities. The findings are discussed in light of models of paranoia in schizophrenia.

Web alert. Development.

A selection of World Wide Web sites relevant to papers published in this issue of Current Opinion in Neurobiology.

Web alert. Neural control.

A selection of World Wide Web sites relevant to reviews published in this issue of Current Opinion in Neurobiology.

Lack of a role of glutathione in cellular nonenzymatic activation of BMS-181174, a novel analogue of mitomycin C.

Recent studies, using a cell-free system, have suggested that thiol-dependent nonenzymatic bioactivation may be responsible for the superior antitumor activity of the mitomycin C analogue BMS-181174 [N-7-[2-(4-nitrophenyldithio)ethyl]mitomycin C] when compared to the parent compound. If operational in tumor cells, this pathway could have enormous clinical implications since tumor cell resistance to a variety of anticancer agents is often associated with increased glutathione (GSH) levels and BMS-181174 may be used to reverse this mechanism of resistance. The present study was undertaken to determine the role of GSH in cellular activation of BMS-181174 using a pair of well-characterized human bladder cancer cells (J82 and SCaBER) as a model. A 20-h pretreatment of J82 and SCaBER cells with a nontoxic concentration of D,L-buthionine-S,R-sulfoximine (BSO) caused about 80-88% reduction in cellular GSH levels. Surprisingly, the sensitivity of both cells to BMS-181174 was increased, not reduced, by BSO-induced GSH depletion. On the other hand, the cytotoxicity of BMS-181174 was significantly reduced in both cells by a 4-h pretreatment with 1 mM GSH. Like BSO, a 4-h pretreatment with another thiol compound (cysteine) resulted in a statistically significant sensitization of both cells to BMS-181174. Cellular GSH levels were not affected in either of the cell lines by pretreatment with GSH or cysteine. In conclusion, the results or the present study argue against a role of GSH in cellular nonenzymatic activation of BMS-181174 in J82 and SCaBER cells.

Eyes wide open: reader and author responsibility in understanding the limits of peer review.

'Medical science can only flourish in a free society and dies under totalitarian repression.' (1) Peer review post-publication is relatively easy to define: when the world decides the importance of publication. Peer review pre-publication is what the scientific community frequently means when using the term 'peer review'. But what it is it? Few will agree on an exact definition; generally speaking, it refers to an independent, third party scrutiny of a manuscript by scientific experts (called peers) who advise on its suitability for publication. Peer review is expensive; although reviewers are unpaid, the cost in time is enormous and it is slow. There is often little agreement among reviewers about whether an article should be published and peer review can be a lottery. Often referred to as a quality assurance process, there are many examples of when peer review failed. Many will be aware of Woo-Suk Hwang's shocking stem cell research misconduct at Seoul National University. (2) Science famously published two breakthrough articles that were found subsequently to be completely fabricated and this happened in spite of peer review. Science is not unique in making this error. However, love it or hate it, peer review, for the present time at least, is here to stay. In this article, Philippa Benson, Managing Editor of Science Advances (the first open access journal of the American Association for the Advancement of Science), discusses the merits of peer review. Dr Benson has extensive experience in the publishing world and was Executive Director of PJB Consulting, a not-for-profit organisation supporting clients on issues related to converting to full electronic publishing workflows as well as challenges working with international authors and publishers. Her clients included the Public Library of Science journals, the American Society for Nutrition and the de Beaumont Foundation. She recently co-authored a book, What Editors Want: An Author's Guide to Scientific Journal Publishing (University of Chicago Press), which helps readers understand and navigate the publishing process in high impact science and technical journals. Her master's and doctorate degrees are from Carnegie Mellon University. JYOTI SHAH Commissioning Editor References 1. Eaton KK . Editorial: when is a peer review journal not a peer review journal? J Nutr Environ Med 1997 ; 7 : 139 - 144 . 2. van der Heyden MA , van de Ven T , Opthof T . Fraud and misconduct in science: the stem cell seduction . Neth Heart J 2009 ; 17 : 25 - 29 .

Are faces of different species perceived categorically by human observers?

What are the species boundaries of face processing? Using a face-feature morphing algorithm, image series intermediate between human, monkey (macaque), and bovine faces were constructed. Forced-choice judgement of these images showed sharply bounded categories for upright face images of each species. These predicted the perceptual discrimination boundaries for upright monkey-cow and cow-human images, but not human-monkey images. Species categories were also well-judged for inverted face images, but these did not give sharpened discrimination (categorical perception) at the category boundaries. While categorical species judgements are made reliably, only the distinction between primate faces and cow faces appears to be categorically perceived, and only in upright faces. One inference is that humans may judge monkey faces in terms of human characteristics, albeit distinctive ones.

Gender-related differences in susceptibility of A/J mouse to benzo[a]pyrene-induced pulmonary and forestomach tumorigenesis.

Benzo[a]pyrene (BP) is a suspected human carcinogen and is known to produce tumors in the lung and forestomach of mice. Glutathione (GSH) S-transferases (GST) play a major role in the detoxification of the ultimate carcinogen of BP, (+)-anti-7,8-dihydroxy-9,10-oxy-7,8,9,10-tetrahydrobenzo[a]pyrene ((+)-anti-BPDE). Previous studies have shown gender-related differences in the expression of GST isoenzymes in mice. The present study was designed to test the hypothesis whether gender-related differences in the expression of GST isoenzymes can affect the susceptibility of mice to BP-induced lung and forestomach tumorigenesis. The expression of pi class isoenzyme mGSTP1-1, which is highly efficient in the detoxification of (+)-anti-BPDE, was approximately 3.0- and 1.5-fold higher in the liver and forestomach of male A/J mouse, respectively, as compared with the female. The levels of other major GST isoenzymes, mGSTA3-3 (alpha class), mGSTM1-1 (mu class) and mGSTA4-4 (alpha class), were also significantly higher in the liver of the male mouse as compared with the female. While pulmonary mGSTP1-1 expression did not differ significantly between male and female A/J mice, the expression of mGSTA3-3, mGSTM1-1 and mGSTA4-4 was significantly higher (1.4-4.0-fold) in the lung of the male A/J mouse as compared with the female. At lower concentrations of BP (0.5 mg BP/mouse), the tumor incidence/multiplicity was significantly higher in the lung as well as in the forestomach of female mice as compared with male mice. For example, while 30% of the female mice developed pulmonary tumors 26 weeks after the first 0.5 mg BP administration, none of the male mice had tumors in their lungs. At higher doses of BP (1.5 mg BP/mouse), however, this differential was either abolished or relatively less pronounced. Our results suggest that up to a certain threshold of BP exposure the levels of GST isoenzymes may be an important determinant of susceptibility to BP-induced tumorigenesis in mice.

Recognizing one's own face.

We report two studies of facial self-perception using individually tailored, standardized facial photographs of a group of volunteers and their partners. A computerized morphing procedure was used to merge each target face with an unknown control face. In the first set of experiments, a discrimination task revealed a delayed response time for the more extensively morphed self-face stimuli. In a second set of experiments, functional magnetic resonance imaging (fMRI) was used to measure brain activation while subjects viewed morphed versions of either their own or their partner's face, alternating in blocks with presentation of an unknown face. When subjects viewed themselves (minus activation for viewing an unknown face), increased blood oxygenation was detected in right limbic (hippocampal formation, insula, anterior cingulate), left prefrontal cortex and superior temporal cortex. In the partner (versus unknown) experiment, only the right insula was activated. We suggest that a neural network involving the right hemisphere in conjunction with left-sided associative and executive regions underlies the process of visual self-recognition. Together, this combination produces the unique experience of self-awareness.

Abnormality of von Willebrand factor in patients with hemoglobin E-beta (0) thalassemia.

The authors have identified six Southeast Asian patients ranging in age from 14 to 21 years with hemoglobin E-beta(0) thalassemia and a coagulopathy involving von Willebrand factor (vWF). These patients had normal or only slightly decreased plasma clotting factor levels. The activated partial thromboplastin time was prolonged in four of the patients. The abnormal feature common to all patients was a qualitative loss of high molecular weight multimers of vWF by crossed immunoelectrophoresis (vWF:CIE). Plasma vWF antigen concentration (vWF:Ag) and ristocetin cofactor activity (vWF:RCo) also were decreased and bleeding time prolonged in three patients. Epistaxis was present in two. No family history of increased bleeding tendency was present in any patient. Coagulation parameters and vWF:CIE were normal in two first-degree relatives without this hemoglobinopathy. vWF abnormalities and clinical manifestations were greatest in those patients with the most severe anemia and hepatosplenomegaly. These six patients appear to have an acquired abnormality of vWF, although they lack the clinical characteristics of acquired von Willebrand disease. While the etiology of this abnormality is unclear, the authors speculate that proteolysis of vWF secondary to extramedullary hematopoiesis or loss through high cardiac output shear stress in these anemic patients may be involved.

Towards a functional neuroanatomy of self processing: effects of faces and words.

We studied the neural correlates of self vs. non-self judgements using functional magnetic resonance imaging (fMRI). Individually tailored faces and personality trait words were used as stimuli in three experiments (exp.). In the first two experiments, brain activation was measured while subjects viewed morphed versions of either their own (self face exp.) or their partner's face (partner's face exp.), alternating in blocks with presentation of an unknown face. In the self face exp. right limbic areas (hippocampal formation, insula, anterior cingulate), the right middle temporal lobe, left inferior parietal and left prefrontal regions showed signal changes. In the partner's face exp., only the right insula was activated. In the third exp., subjects made decisions about psychological trait adjectives previously categorized as describing their own attributes. Activation was present in the precuneus, the left parietal lobe, left insula/inferior frontal gyrus and the left anterior cingulate. A reaction time advantage was present when subjects responded to self-relevant words. The main area with signal changes during self-reference processing, regardless of the type of stimulus, was the left fusiform gyrus. The self-relevant stimuli engaged to a differential extent long term and working memory, semantic and emotional processes. We suggest that regions activated by these stimuli are engaged in self-processing.

Involuntary eye movements in response to first- and second-order motion.

We trained monkeys to maintain fixation while first- and second-order motion stimuli were displayed centrally in the visual field. Stimulus velocity, spatial frequency and contrast were varied to determine differences in patterns of involuntary eye movements elicited by random onset of stimulus motion. We observed different patterns of eye movement latency and velocity suggesting very early (< or = 100 ms) components of oculomotor activity are used to initiate smooth pursuit of object trajectory. Eye movement latency was insensitive to the complexity of stimulus motion, whereas second-order motion elicited faster eye movements than first-order motion. Instantaneous eye movement velocity might be related to the earliest stages of visual processing of component motion.

Short-latency ocular following of motion by monkeys during a fixation task.

Short-latency ocular following responses in monkeys, induced by first- and second-order motion during a fixation task, were sensitive to stimulus size, retinal eccentricity and motion duration. Latency of eye movements was no different for first- or second-order motion and simply marked the occurrence of movement in the visual field. Second-order motion produced higher velocity eye movements than did first-order motion. The velocity of eye movements was influenced by the orientation of second-order pattern components as well as their conspicuous energy. Even when partially suppressed by a fixation task, involuntary eye movements during the initial pursuit remain sensitive to several properties of visual motion.

Grating and plaid chrominance motion influences the suppressed ocular following response.

Involuntary eye movements to foveal stimulation were measured in a monkey while it performed a fixation task. Second-order plaid motion generated higher velocities of eye movements than did first-order gratings, yet the latency of the early following response was no different for grating or plaid motion. Nevertheless, early suppressed ocular following responses to isoluminant motion continue to be titrated by stimulus velocity and spatial frequency. Motion defined by 60% luminance contrast gratings and plaids generated a motion signal gain of 60% over chrominance motion. The 20% longer latency of eye movements to chrominance motion may reflect the longer conduction latency of the parvocellular channel and an additional stage in cortical processing en route to motion areas and eye movement control.

Stages in motion processing revealed by the ocular following response.

Motion perception and associated involuntary eye movements depend on factors such as the physical attributes of the stimulus and visual attention. Cues from spatial changes in luminance (first-order motion in the Fourier domain) or more complicated transitions involving two-dimensional patterns (second-order, non-Fourier) require rather different kinds of analyses to detect their net motion. During a fixation task we monitored eye movements induced by the onset of motion to examine the functional properties of the monkey cortical motion processing system. Eye movement velocity was indistinguishable to first- and second-order motion; concomitant response latency confirmed an additional calculation is required to detect the direction and velocity of second-order motion.

Residual motion discrimination using colour information without primary visual cortex.

Previous studies have reported that some patients with damage to striate cortex retain the ability to detect monochromatic light and discriminate direction of achromatic movement in their blind visual fields. We investigated the residual chromatic visual capacity of a well-studied patient (GY) who has a unilateral lesion to striate cortex (V1). The data demonstrated that GY was able to detect and discriminate isoluminant colour targets presented in his blind hemifield. The velocity and contrast of chromatic moving stimuli affected GY's levels of conscious experience of movements he was able to discriminate. As the velocity or contrast was increased, his discrimination performance improved in line with rising visual awareness and judgement confidence. At isoluminance, GY continued to discriminate motion direction with above chance accuracy. These results indicate chromatic signals can also be used to process motion information in the absence of primary visual cortex.

Cortical evoked potentials due to motion contrast in the blind hemifield.

Subcortical visual inputs to motion-selective cortex in primates survive after damage to the primary visual cortex (area 17/V1). Activation of human motion cortex was examined using scalp electrodes in a V1-damaged hemianope. Blind field motion-onset visual evoked potentials (VEPs) shared many of the characteristics associated with sighted vision but were smaller in amplitude and had longer latencies. The representative negative wave (C(II) peak) showed typical dependency on stimulus contrast, its peak latency increased and amplitude decreased as contrast decreased, reflecting the difficulty with which directional information could be detected. VEPs were present at contrasts below 25% when blind field motion was imperceptible even though direction guessing was paradoxically accurate. Subcortical inputs to motion cortex contribute to visual experience but not to conscious perception.

Cytomegalovirus prostatitis.

Tissue demonstration of cytomegalovirus (CMV) within the male genital tract has rarely been reported. We present a case of extensive CMV prostatitis in a homosexual patient with acquired immune deficiency syndrome (AIDS) dying of disseminated CMV infection.

A means of measuring facial expressions and a method for predicting emotion categories in clinical disorders of affect.

In a radical departure from traditional approaches, it was found that only seven measures of facial expression are required to accurately distinguish between normal displays of happiness, sadness, fear, disgust, surprise and anger. Using these prototypical emotion categories it has been shown that particular facial areas in Parkinson's disease (PD) are responsible for communication of blended, rather than the intended expressions. We consider how assessment of facial expressions made in this way can be used to quantify progress of therapeutic intervention in PD. We also show that in gaining a better understanding of the structure of emotion categories, advances in understanding need not be overshadowed by methodological complexity. The simplicity of the approach presented here leads us to propose that the perceptual and behavioural aspects of affective disorders can now be tackled in a unified manner.

Cerebral aneurysms following radiotherapy for medulloblastoma.

Three patients, two males and one female aged 21, 14, and 31 years, respectively, developed cerebral saccular aneurysms several years after undergoing radiotherapy for cerebellar medulloblastoma at 2, 5, and 14 years of age, respectively. Following surgery, all three received combined cobalt-60 irradiation and intrathecal colloidal radioactive gold (198Au) therapy, and died from rupture of the aneurysm 19, 9, and 17 years after the radiotherapy, respectively. Autopsy examination revealed no recurrence of the medulloblastoma, but widespread radiation-induced vasculopathy was found at the base of the brain and in the spinal cord, and saccular aneurysms arose from the posterior cerebral arteries at the basal cistern or choroidal fissure. The aneurysms differed from the ordinary saccular aneurysms of congenital type in their location and histological features. Their locations corresponded to the areas where intrathecally administered colloidal 198Au is likely to pool, and they originated directly from a segment of the artery rather than from a branching site as in congenital saccular aneurysms. It is, therefore, concluded that the aneurysms in these three patients were most likely radiation-induced.