Reading fluent speech from talking faces: typical brain networks and individual differences

Listeners are able to extract important linguistic information by viewing the talker's face-a process known as 'speechreading.' Previous studies of speechreading present small closed sets of simple words and their results indicate that visual speech processing engages a wide network of brain regions in the temporal, frontal, and parietal lobes that are likely to underlie multiple stages of the receptive language system. The present study further explored this network in a large group of subjects by presenting naturally spoken sentences which tap the richer complexities of visual speech processing. Four different baselines (blank screen, static face, nonlinguistic facial gurning, and auditory speech) enabled us to determine the hierarchy of neural processing involved in speechreading and to test the claim that visual input reliably accesses sound-based representations in the auditory cortex. In contrast to passively viewing a blank screen, the static-face condition evoked activation bilaterally across the border of the fusiform gyrus and cerebellum, and in the medial superior frontal gyrus and left precentral gyrus (p < .05, whole brain corrected). With the static face as baseline, the gurning face evoked bilateral activation in the motion-sensitive region of the occipital cortex, whereas visual speech additionally engaged the middle temporal gyrus, inferior and middle frontal gyri, and the inferior parietal lobe, particularly in the left hemisphere. These latter regions are implicated in lexical stages of spoken language processing. Although auditory speech generated extensive bilateral activation across both superior and middle temporal gyri, the group-averaged pattern of speechreading activation failed to include any auditory regions along the superior temporal gyrus, suggesting that f luent visual speech does not always involve sound-based coding of the visual input. An important finding from the individual subject analyses was that activation in the superior temporal gyrus did reach significance (p < .001, small-volume corrected) for a subset of the group. Moreover, the extent of the left-sided superior temporal gyrus activity was strongly correlated with speechreading performance. Skilled speechreading was also associated with activations and deactivations in other brain regions, suggesting that individual differences ref lect the efficiency of a circuit linking sensory, perceptual, memory, cognitive, and linguistic processes rather than the operation of a single component process.     

Virulence and cord blood mononuclear cells cytokine production induced by perinatal listeria monocytogenes strains from different phylogenetic lineages

Some of the phylogenetic lineages of Listeria monocytogenes are more likely to cause invasive disease in humans than are strains from other phylogenetic lineages. This suggests that strains belonging to these lineages display different levels of pathogenicity. To investigate this, we carried out a plaque-forming assay with HT-29 cells to evaluate the virulence of six perinatal strains from the three lineages that compose the species. All of the strains were largely over the 3.34 cutoff (between 4.29 and 5.97 mean log) with the HT-29 model and can therefore be considered to be equally virulent. We also explored part of the immune response of cord blood mononuclear cells by measuring cytokine production. All strains induced the production of similar amounts of TNF-alpha and IL-1beta. High concentrations of IL-6 and IL-8 were produced (between 6,000 and 17,000 pg/ml), whereas little or no IFN-gamma or IL-12 was produced. Thus, there is no difference between the strains from the three genetic lineages in terms of virulence or cytokine response. Given the epidemiological distribution of the serotypes responsible for human listeriosis and the genetic structure of the L. monocytogenes species, our results suggest: (i) that all strains from lineage I (serotypes 1/2b and 4b), a genetically homogeneous subpopulation, have a similar level of pathogenicity, and (ii) that lineage II (serotypes 1/2a and 1/2c), which is genetically more heterogeneous, is composed of strains with different levels of pathogenicity. The ones responsible for invasive diseases, particularly perinatal infections, display a similar level of pathogenicity to lineage-I strains and are not virulence-attenuated strains that can only infect the most immunocompromised hosts, whereas the other lineage-II strains are probably less pathogenic for humans.     

Comparing utility scores before and after hearing-aid provision

Utility scores were estimated for 609 hearing-impaired adults who completed EQ-5D, Health Utilities Index Mark III (HUI3) and SF-6D survey instruments both before and after being provided with a hearing aid. Pre-intervention, the mean utility scores for EQ-5D (0.80) and SF-6D (0.78) were significantly higher than the mean HUI3 utility score (0.58). Post-intervention, the mean improvement in the HUI3 (0.06 change) was significantly higher than the mean improvement according to the EQ-5D (0.01 change) or SF-6D (0.01 change). The estimated cost effectiveness of hearing-aid provision is therefore likely to be dependent on which instrument is used to measure utility.     

Locally up-regulated lymphotoxin alpha,not systemic tumor necrosis factor alpha,is the principle mediator of murine cerebral malaria

Cerebral malaria (CM) causes death in children and nonimmune adults. TNF-alpha has been thought to play a key role in the development of CM. In contrast, the role of the related cyto-kine lymphotoxin alpha (LTalpha) in CM has been overlooked. Here we show that LTalpha, not TNFalpha, is the principal mediator of murine CM. Mice deficient in TNFalpha (B6.TNFalpha-/-) were as susceptible to CM caused by Plasmodium berghei (ANKA) as C57BL/6 mice, and died 6 to 8 d after infection after developing neurological signs of CM, associated with perivascular brain hemorrhage. Significantly, the development of CM in B6.TNFalpha-/- mice was not associated with increased intracellular adhesion molecule (ICAM)-1 expression on cerebral vasculature and the intraluminal accumulation of complement receptor 3 (CR3)-positive leukocytes was moderate. In contrast, mice deficient in LTalpha (B6.LTalpha-/-) were completely resistant to CM and died 11 to 14 d after infection with severe anemia and hyperparasitemia. No difference in blood parasite burden was found between C57BL/6, B6.TNFalpha-/-, and B6.LTalpha-/- mice at the onset of CM symptoms in the two susceptible strains. In addition, studies in bone marrow (BM) chimeric mice showed the persistence of cerebral LTalpha mRNA after irradiation and engraftment of LTalpha-deficient BM, indicating that LTalpha originated from a radiation-resistant cell population.     

Successful management of severe respiratory failure combining heliox with noninvasive high-frequency percussive ventilation

Heliox has been shown to be beneficial in the management of different obstructive pulmonary disorders. High-frequency percussive ventilation has recently been advocated to treat lung injury in children with reduced lung compliance. We report our experience of combining heliox with noninvasive high-frequency percussive ventilation in a 5-yr-old boy with severe acute respiratory failure resulting from advanced cystic fibrosis lung disease. The dramatic improvement allowed stabilization and withholding of endotracheal intubation. We hypothesize that this approach improved gas exchange by enhancing molecular diffusion and by favoring laminar flow throughout the upper and lower airways. Further investigations should study the mechanisms of this noninvasive bimodal therapy.     

Short-term repeatability and correlates of laboratory measures of nasal function in patients with seasonal allergic rhinitis

The purpose of this study was to determine the variability of laboratory nasal function tests in 26 patients (18 female) with seasonal allergic rhinitis (SAR) (mean age 38.1 years). Their usual medication for SAR was withheld for 2 separate one week washout periods, separated by at least 2 weeks, in order to produce clinically significant nasal airflow obstruction. Measurements were made on both occasions for nasal nitric oxide (NO), nasal peak inspiratory flow (nPIF), oral PIF (oPIF), nasal forced inspiratory flow rate in 1 second (nFIV1), oral FIV1 (oFIV1). The respective nasal-oral ratios for FIV1 and PIF were also determined. The intra-individual coefficient of variation was: NO = 14%, nFIV1 = 4%, nFIV1/oFIV1 ratio = 10%, nPIF = 8% and nPIF/oPIF ratio = 12%. Linear regression analysis showed significant (p < 0.05) correlations between nPIF and nFIV1 (R2 = 0.45) and between nPIF/oPIF and nFIV1/oFIV1 (R2 = 0.20). In conclusion, there was a good correlation between the two methods of nasal inspiratory flow, although FIV1 had a lesser degree of variability.     

Neonatal bacterial infection by maternal-fetal contamination: for a change in approach? 2. Uncertainties and proposals

Based on a critical analysis of the literature, it is clear that even though mortality has decreased to 10-15%, the prevalence of neonatal bacterial infections remains dramatically stable. Precise risk factors can be identified in most cases of neonatal infection, but remain uncertain in many others: Streptococcus agalactiae is found in only 40% of the cases of sepsis; Escherichia coli, Haemophilus influenzae, Pneumococcus, and group A Streptococcus strains should also be considered for a real prophylactic strategy; context (prematurity), lack of a consensual attitude for intrapartum strategies; management schemes for asymptomatic neonates. Based on these observations, we make proposals for a realistic attitude for everyday practice based on risk factors, maternal and neonatal bacterial sampling procedures, and modalities for neonatal antibiotic therapy.     

Proposal of the Physicians' Working Group for Single-Payer National Health Insurance

The Physicians' Working Group for Single-Payer National Health Insurance^*

JAMA. 2003;290:798-805.

The United States spends more than twice as much on health care as the average of other developed nations, all of which boast universal coverage. Yet more than 41 million Americans have no health insurance. Many more are underinsured. Confronted by the rising costs and capabilities of modern medicine, other nations have chosen national health insurance (NHI). The United States alone treats health care as a commodity distributed according to the ability to pay, rather than as a social service to be distributed according to medical need. In this market-driven system, insurers and providers compete not so much by increasing quality or lowering costs, but by avoiding unprofitable patients and shifting costs back to patients or to other payers. This creates the paradox of a health care system based on avoiding the sick. It generates huge administrative costs that, along with profits, divert resources from clinical care to the demands of business. In addition, burgeoning satellite businesses, such as consulting firms and marketing companies, consume an increasing fraction of the health care dollar. We endorse a fundamental change in US health care—the creation of an NHI program. Such a program, which in essence would be an expanded and improved version of traditional Medicare, would cover every American for all necessary medical care. An NHI program would save at least $200 billion annually (more than enough to cover all of the uninsured) by eliminating the high overhead and profits of the private, investor-owned insurance industry and reducing spending for marketing and other satellite services. Physicians and hospitals would be freed from the concomitant burdens and expenses of paperwork created by having to deal with multiple insurers with different rules, often designed to avoid payment. National health insurance would make it possible to set and enforce overall spending limits for the health care system, slowing cost growth over the long run. An NHI program is the only affordable option for universal, comprehensive coverage.