Perception, cognition, and action in hyperspaces: implications on brain plasticity, learning, and cognition

We live in a three-dimensional (3D) spatial world; however, our retinas receive a pair of 2D projections of the 3D environment. By using multiple cues, such as disparity, motion parallax, perspective, our brains can construct 3D representations of the world from the 2D projections on our retinas. These 3D representations underlie our 3D perceptions of the world and are mapped into our motor systems to generate accurate sensorimotor behaviors. Three-dimensional perceptual and sensorimotor capabilities emerge during development: the physiology of the growing baby changes hence necessitating an ongoing re-adaptation of the mapping between 3D sensory representations and the motor coordinates. This adaptation continues in adulthood and is quite general to successfully deal with joint-space changes (longer arms due to growth), skull and eye size changes (and still being able of accurate eye movements), etc. A fundamental question is whether our brains are inherently limited to 3D representations of the environment because we are living in a 3D world, or alternatively, our brains may have the inherent capability and plasticity of representing arbitrary dimensions; however, 3D representations emerge from the fact that our development and learning take place in a 3D world. Here, we review research related to inherent capabilities and limitations of brain plasticity in terms of its spatial representations and discuss whether with appropriate training, humans can build perceptual and sensorimotor representations of spatial 4D environments, and how the presence or lack of ability of a solid and direct 4D representation can reveal underlying neural representations of space.Published versio

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

Neural activity in the reward-related brain regions predicts implicit self-esteem: A novel validity test of psychological measures using neuroimaging

Self-esteem, arguably the most important attitudes an individual possesses, has been a premier research topic in psychology for more than a century. Following a surge of interest in implicit attitude measures in the 90s, researchers have tried to assess self-esteem implicitly in order to circumvent the influence of biases inherent in explicit measures. However, the validity of implicit self-esteem measures remains elusive. Critical tests are often inconclusive, as the validity of such measures is examined in the backdrop of imperfect behavioral measures. To overcome this serious limitation, we tested the neural validity of the most widely used implicit self-esteem measure, the implicit association test (IAT). Given (1) the conceptualization of self-esteem as attitude toward the self, and (2) neuroscience findings that the reward-related brain regions represent an individual’s attitude or preference for an object when viewing its image, individual differences in implicit self-esteem should be associated with neural signals in the reward-related regions during passive-viewing of self-face (the most obvious representation of the self). Using multi-voxel pattern analyses (MVPA) on functional magnetic resonance imaging (fMRI) data, we demonstrated that the neural signals in the reward-related regions were robustly associated with implicit (but not explicit) self-esteem, thus providing unique evidence for the neural validity of the self-esteem IAT. In addition, both implicit and explicit self-esteem were related, although differently, to neural signals in regions involved in self-processing. Our finding highlights the utility of neuroscience methods in addressing fundamental psychological questions and providing unique insights into important psychological constructs

Effect of hospitalization on fetal growth

Objective : We aimed to demonstrate the effect of prolonged hospitalization on fetal growth in cases of threatened preterm labor (TPL). Methods : In this retrospective cohort study, we included women who received prenatal care for TPL but delivered their child after 36 weeks of gestation. These were compared with a control group of healthy pregnant women and fetuses delivered at term. Fetal growth was compared using biparietal diameter, abdominal circumference (AC), femur length, and estimated fetal weight (EFW) assessed using ultrasonography at 18, 26, 30, and 36 weeks of gestation. Neonatal parameters at birth were also compared. Results : In total, we enrolled 228 control women and 114 women with TPL who were treated with hospitalization, including bed rest. The AC at 30 and 36 weeks of gestation and EFW at 36 weeks of gestation were smaller in women treated with bed rest than for normal pregnant women. The mean duration of pregnancy was shorter in the hospitalization group than in the control group. Neonatal weight, length, head circumference, and chest circumference at birth were smaller after prolonged hospitalization for TPL than after normal pregnancy. Conclusion : Prolonged hospitalization for threatened preterm labor is associated with impaired fetal growth, particularly AC

Experimental Evaluation of Effects of Intra-Aortic Balloon Pumping (IABP) on Ischemic Heart

The intraaortic balloon pumping (IABP) has been widely empoyed in the management of ventricular power failure. The effects of IABP were studied in a large number of reports. However, the efficacy of IABP has not been certified with reference to the severity of myocardial ischemia. Experimentally augmentation of coronary blood flow were observed on acute ischemic heart by ligation of the anterior descending artery. It has shown from the view of increased coronary blood flow that excess of 50ml/min/kg of coronary blood flow were obtained in functional reserved myocardium with ischemia. However, the efficacy of IABP on acute ischemic heart can not be precipitated by severe damage of the myocardium. The usefulness of IABP was elucidated by functional myocardial level of at least 50mmHg of LVP, 40mmHg of LVEDP and 1000mmHg/sec of max dp/dt respectivelly and it is emphasized that immediate application of IABP for cardiogenic shock allows to improve the further myocardial depression

An Experimental Functional Evaluation of End to Side Anastomosis Related to Operative Procedures of Tracheobronchial Reconstruciotn

End to side anastomosis between the trachea and the bronchus was widely employed as one of bronchial reconstructed method. However, functional evaluation undergone bronchial reconstruction did not completely display its superiority functionally. This study was undertaken to determine whether end to side anastomosis was far superior in regard to reserved pulmonary function by means of observation on changes in size of anastomotic area on xp film delineated during inspiration and exspiration simultaneously and also by intrabronchial pressure tracing. The results were as follows. 1) The creation of window defect on the tracheal wall prior to anastomosis was necessary to maintain an adequate anastomotic area. 2) The end to side anastomosis obliquely results in an excellent ventilation functionally. In contrast, the ill effects were disclosed by moderate angulation as far as exceeded 45 degree against tracheal wall owing to loss of rigidity in bronchial wall. From the present study, we concluded that end to side anastomosis obliquely with moderate degree should be avoided because of bronchial stenosis produced by bronchial collapse due to loss of supporting ability of bronchial cartilage

Enhanced osseointegration by the chemotactic activity of plasma fibronectin for cellular fibronectin positive cells.

Plasma fibronectin (pFN) is known to regulate cell growth, differentiation or survival of osteoblasts in vitro. It is also speculated to be important for the early phase of osseointegration, however, its actual in vivo behavior is unknown. The objective of this study is to clarify the role of pFN during osseointegration. We developed a titanium ion-plated acrylic implant (Ti-acryl) for thin sectioning without removal of the implant. Either Ti-acryl or pFN-coated Ti-acryl (FN-Ti-acryl) was implanted in the mouse femur. Samples were taken on days 1-7 and on day 14 after the operation, and were decalcified and paraffin embedded. The bone healing process and immunofluorescence localization of pFN and cellular fibronectin (cFN), a marker for fibroblastic cells were examined. Simultaneously, the effect of pFN on chemotaxis, proliferation and differentiation of bone marrow stromal cells (BMSCs) was analyzed in vitro. The in vivo results showed that faster direct bone formation was seen for the FN-Ti-acryl group compared to the Ti-acryl group. The in vitro results showed that pFN significantly promoted BMSCs chemotaxis, however, had no effect on proliferation or differentiation. The results indicate that pFN regulated chemotaxis of osteogenic cells and coating the implant with pFN enhanced earlier osseointegration

Clinical Evaluation of Immune Response in Patients with Cancer

Immune response was clinically evaluated in 25 patients with carcinoma compared with 26 of non cancer patients by means of lymphocyte transformation against PHA which was shown as stimulation index. In patients with cancer, stimulation index showed apparently as low as an average of 38 compared with 82 of non-cancer patients. Furthermore, the level of stimulation index was a corresponding correlation to age in which low activation was presented in the elderly. According to diseased organs, the weak response of stimulation index against PHA were observed in patients with the carcinoma of the esophagus and the lung. The response of skin test for PPD, PHA, SK-SD and candida were inhibited in patients with advanced cancer of stage III and IV compared with that of stage I and II. These responses were also suppressed in postoperative course until at least 6 months after surgery. From these results, it was noted that operative procedures provoked the induced weakness against host defense immunologically. However, it was certified that the use of immunopotentiator faciliated the activity of immune response during postoperative period for the patients with no severely advanced lung cancer of stage I and II despite of little effects for patients with advanced lung cancer of stage III and IV. It was concluded that immune response of patients with cancer was inhibited by advancing carcinoma and by operative procedures but the use of immunopotentiator was beneficial to promote the host defense during postoperative period

The Uteroglobin Gene G38A Polymorphism Is Not Associated with Kawasaki Disease

This study analyzed the genomic DNA extracted from 170 patients with Kawasaki disease as well as their clinical and laboratory parametersto determine whether uteroglobin gene polymorphism, which may be associated with the morbidity rate and severity of IgA nephropathy, is involvedin the pathogenesis of Kawasaki disease, which is another type of vasculitic syndrome in childhood. The uteroglobin genotype at position38 was determined by Sau96I digestion of PCR products. The uteroglobin genotype and allele frequency in Kawasaki disease patientswere compared with those of published control data reported by three independent studies on Japanese individuals. The clinical parametersinvestigated were age at onset, gender, duration of fever, white blood cell count, C-reactive protein, aspartate aminotransferase, alanineaminotransferase and total protein. No significant difference associated with the uteroglobin genotype was observed in the clinical parameters.The genotypic and allele frequencies at position 38 of the uteroglobin gene did not differ significantly in the three studies of Japanese healthycontrols and the present study. The logistic regression analysis demonstrated that no clinical parameter was associated with the progressionto coronary artery lesions except for the duration of fever (odds ratio = 1.7; 95% confidential interval = 1.42-2.05). In conclusion, the presentstudy failed to prove an association of uteroglobin gene polymorphism with the morbidity rate or the severity of Kawasaki disease, but suggestedthe existence of a factor contributing to the onset of Kawasaki disease and progression to coronary artery lesions in Kawasaki diseasepatients

A Functional Evaluation of Bronchial Reconstructed Lung with Special Reference to Denervation

Bronchoplastic procedures for lung cancer were suitable operative method to reserve pulmonary function and to enlarge the resected area. However, functional evaluation is not necessarily achieved in bronchial reconstructed lung, especially with reference to denervation. In this study the influence of denervation was investigated experimentally by pulmonary perfused wedge method in which vascular tonus was directly illustrated and by measurement of oxygen saturation (Sao2) of pulmonary venous blood in which the ability of oxygen uptake was elucidated. When comparing the results of denervation with regard to operative procedures of bronchoplasty, bronchoplasty with sleeve anastomosis of pulmonary artery and autotransplantation respectively, the deteriorate effects related to bronchoplasty were not observed as compared to autotransplantation