Emergence of symmetry selectivity in the visual areas of the human brain: fMRI responses to symmetry presented in both frontoparallel and slanted planes

Symmetry is effortlessly perceived by humans across changes in viewing geometry. Here, we re‐examined the network subserving symmetry processing in the context of up‐to‐date retinotopic definitions of visual areas. Responses in object selective cortex, as defined by functional localizers, were also examined. We further examined responses to both frontoparallel and slanted symmetry while manipulating attention both toward and away from symmetry. Symmetry‐specific responses first emerge in V3 and continue across all downstream areas examined. Of the retinotopic areas, ventral occipital VO1 showed the strongest symmetry response, which was similar in magnitude to the responses observed in object selective cortex. Neural responses were found to increase with both the coherence and folds of symmetry. Compared to passive viewing, drawing attention to symmetry generally increased neural responses and the correspondence of these neural responses with psychophysical performance. Examining symmetry on the slanted plane found responses to again emerge in V3, continue through downstream visual cortex, and be strongest in VO1 and LOB. Both slanted and frontoparallel symmetry evoked similar activity when participants performed a symmetry‐related task. However, when a symmetry‐unrelated task was performed, fMRI responses to slanted symmetry were reduced relative to their frontoparallel counterparts. These task‐related changes provide a neural signature that suggests slant has to be computed ahead of symmetry being appropriately extracted, known as the “normalization” account of symmetry processing. Specifically, our results suggest that normalization occurs naturally when attention is directed toward symmetry and orientation, but becomes interrupted when attention is directed away from these features.     

Quality assurance in preschool surveillance

A quality assurance programme was used to evaluate community and primary care based preschool surveillance using the National Child Health Computer System in 40 examination centres. Quarterly reports were generated from returns from clinical medical officers and general practitioners to list non-attenders, uptake, and timeliness for the four preschool checks. These provided rapid and comparative feedback on personal performance for participating health professionals and led to marked rises in recorded timeliness and uptake against preset targets. Pre-existing uptake was highest at the 6 week check with least overall improvement. Greatest improvements occurred at the 18 month health visitor check but, in general, results plateaued when the programme had been in use for 12 to 18 months. Particular problems such as data legibility and mobile populations were identified and solutions formulated. It is postulated that improvements in performance were due to enhanced professional motivation as no other factors changed. This system provides a valuable contribution in the light of changing patterns of service provision.     

No Effect of Acute Ethanol Administration on Hepatic Protein Synthesis and Export in the Rat in Vivo

Ethanol was administered as a single p.o. dose (2.88 g X kg-1) to male rats (220-265 g body weight) to give blood alcohol concentrations of 40-50 mM for the following 3 hr. Controls were given isoenergetic amounts of either sucrose or lipid. Liver protein synthetic rates were measured during a 20 min interval at the end of the 3 hr period following the administration of diets. Although ethanol caused a 32% reduction of the incorporation of labelled valine into liver protein compared to the sucrose group during the 20 min interval, no such reduction was found when the synthetic rate of stationary liver protein was calculated (182 vs. 214 (not significant) pmol X mg protein-1 X min-1) for same interval. There was no difference between the ethanol and lipid group with regard to either incorporation or synthetic rates. Incorporation of valine into plasma proteins was reduced in the ethanol group compared to the sucrose group, but not compared to the lipid control group, again demonstrating no ethanol-specific effect. When the incorporation into plasma proteins was divided by the specific radioactivity of valyl-tRNA at 20 min, the difference between the ethanol and the sucrose group disappeared. The fraction of newly synthesized proteins exported to the plasma measured 40 min after the injection of labeled valine, was equal in all three treatment groups. It was concluded that acute administration of ethanol has no consistent effect on liver protein synthesis and secretion in vivo.     

Cognitive Processing Therapy for Posttraumatic Stress Disorder via Telehealth: Practical Considerations During the COVID-19 Pandemic

The global outbreak of COVID-19 has required mental health providers to rapidly rethink and adapt how they provide care. Cognitive processing therapy (CPT) is a trauma-focused, evidence-based treatment for posttraumatic stress disorder that is effective when delivered in-person or via telehealth. Given current limitations on the provision of in-person mental health treatment during the COVID-19 pandemic, this article presents guidelines and treatment considerations when implementing CPT via telehealth. Based on lessons learned from prior studies and clinical delivery of CPT via telehealth, recommendations are made with regard to overall strategies for adapting CPT to a telehealth format, including how to conduct routine assessments and ensure treatment fidelity.     

Effect of chronic ethanol treatment on tryptophan oxygenase, tyrosine aminotransferase and general protein metabolism in the intact and perfused rat liver

Male Wistar rats (275–300 g body wt) were given ethanol to provide 31 percent of the total calories, while sucrose replaced ethanol isocalorically in controls. Thirty-six per cent of the calories were provided by fat in both groups.Tryptophan oxygenase (TO) activity was reduced to about 60 per cent of control activity in livers from rats treated with ethanol for 38 days. This effect was not a consequence of a reduction of in vivo corticosterone levels in the treated animals. Tyrosine aminotransferase (TAT) activity was unchanged in these livers. When the livers were perfused with dexamethasone (20 μg/ml), the induction of both enzymes was significantly lower in ethanol-treated rats. The incorporation of labelled amino acids into protein 30 and 45 min after the addition of label was also reduced in livers from treated rats. The degradation of TO, TAT and general proteins, measured in the perfused liver after cycloheximide (50 μg/ml) was not significantly affected by previous ethanol consumption. No obvious leakage of liver proteins to the perfusate could be registered after ethanol treatment. Ethanol treatment did not significantly influence plasma bilirubin, liver bile production, liver lipids or gross histological appearance of the liver. It was concluded that liver TO, TAT and general protein synthesis was reduced as a consequence of the previous chronic intake of ethanol independent of changes in the other liver parameters measured.     

Maternal occupational and hobby chemical exposures as risk factors for neural tube defects

In a case-control study, we investigated whether occupational and nonoccupational (hobbies) chemical exposures to women in the periconceptional period increased their risk for having neural tube defect-affected pregnancies. Women were asked about occupational tasks and hobbies performed during the 3 months before through 3 months after conception. Based on her reported occupational tasks and hobbies, an industrial hygienist assigned a priori defined exposure categories to each task and hobby. The exposure categories included 74 chemical groups, 9 "end-use" chemical groups, and organic solvents. Face-to-face interviews were conducted with mothers of 538 (88% of eligible) infants or fetuses with neural tube defect and mothers of 539 (88%) randomly selected, nonmalformed, live-born infants from a population-based 1989-1991 cohort of California births (N = 703,518). Our results suggested that maternal exposures in the periconceptional period to a variety of chemicals associated with occupational and nonoccupational activities did not contribute substantially to risk of neural tube defects in offspring. We observed no effect estimate greater than 2.0 for maternal exposures to the chemical agent groups studied. We did not observe substantially elevated risks associated with maternal exposures to any of the end-use chemical groups or to organic solvents. Considering occupational exposures only among women who worked did not substantially alter results. Adjustment for maternal vitamin use, race/ethnicity, or education level also did not substantially alter the observed associations.