Boosting perceptual learning by fake feedback

AbstractHow does the brain control its sensory plasticity using performance feedback? We examined this question using various types of fake feedback in perceptual learning paradigm. We demonstrated that fake feedback indicating a larger performance improvement facilitated learning compared with genuine feedback. Variance of the fake feedback modulated learning as well, suggesting that feedback uncertainty can be internally evaluated. These results were explained by a computational model which controlled the learning rate of the visual system based on Bayesian estimation of performance gradient incorporating an optimistic bias. Our findings suggest that sensory plasticity might be controlled by high-level cognitive processes

The Developmental Changes in Cube Copying Abilities of Japanese Children with Typical Development

Purpose: The purpose of this study was to analyze the developmental changes in Necker cube copying and isometric perspective cube copying abilities of Japanese children of typical development.Methods and Results: [Study-1] A total of 40 individuals aged 5-18 years participated in Study-1. The Necker cube copying task was administered, and scores were assigned based on the method developed by Yorimitsu et al. (2013). The results showed that the scores increased significantly for children in the 8-9 years age group (p < 0.01).[Study-2] A total of 32 individuals aged 6-10 years participated in Study-2. The isometric perspective cube copying task was administered, and scores were assigned based on the method developed by Otomo (2009). The results showed that the scores increased significantly for children in the 7-8 years age group (p < 0.05).Conclusions: Japanese children of typical development were able to perform the Necker cube copying task from approximately nine years of age. The same participants were able to perform the isometric perspective cube copying task from approximately eight years of age

Emphysematous Cystitis in a Patient with Type 2 Diabetes Mellitus

A 62-year-old woman with a history of poorly controlled type 2 diabetes mellitus was admitted to our hospital with a 3-week history of mild fever, vomiting, and anorexia. Abdominal computed tomography (CT) showed bilateral hydronephrosis and gas accumulation in the urinary bladder wall and left ureter. Laboratory tests showed leukocytosis and elevated C-reactive protein level. Urine culture showed heavy growth of Escherichia coli. The final diagnosis was emphysematous cystitis. The patient was treated with systemic antibiotics and drainage using a urethral catheter. The clinical and radiographic findings resolved rapidly, and she was discharged from the hospital on day 28. Emphysematous cystitis is a relatively rare urinary tract infection associated with gas formation, and has the potential for a serious outcome if untreated. Early detection by imaging studies such as CT is important in providing prompt treatment and favorable clinical outcome

Aggregation of scaffolding protein DISC1 dysregulates phosphodiesterase 4 in Huntington’s disease

Huntington’s disease (HD) is a polyglutamine (polyQ) disease caused by aberrant expansion of the polyQ tract in Huntingtin (HTT). While motor impairment mediated by polyQ-expanded HTT has been intensively studied, molecular mechanisms for nonmotor symptoms in HD, such as psychiatric manifestations, remain elusive. Here we have demonstrated that HTT forms a ternary protein complex with the scaffolding protein DISC1 and cAMP-degrading phosphodiesterase 4 (PDE4) to regulate PDE4 activity. We observed pathological cross-seeding between DISC1 and mutant HTT aggregates in the brains of HD patients as well as in a murine model that recapitulates the polyQ pathology of HD (R6/2 mice). In R6/2 mice, consequent reductions in soluble DISC1 led to dysregulation of DISC1-PDE4 complexes, aberrantly increasing the activity of PDE4. Importantly, exogenous expression of a modified DISC1, which binds to PDE4 but not mutant HTT, normalized PDE4 activity and ameliorated anhedonia in the R6/2 mice. We propose that cross-seeding of mutant HTT and DISC1 and the resultant changes in PDE4 activity may underlie the pathology of a specific subset of mental manifestations of HD, which may provide an insight into molecular signaling in mental illness in general

IgSF11 regulates osteoclast differentiation through association with the scaffold protein PSD-95

Kim, H., Takegahara, N., Walsh, M.C. et al. IgSF11 regulates osteoclast differentiation through association with the scaffold protein PSD-95. Bone Res 8, 5 (2020). https://doi.org/10.1038/s41413-019-0080-