Does Integration Produce Masking or Protect from it?

Perception ◽  
1981 ◽  
Vol 10 (1) ◽  
pp. 71-83 ◽  
Author(s):  
David Navon ◽  
Dean Purcell

To examine the role of integration in pattern masking, possible disruptive effects of integration were minimized by using a mask that overlaid completely all targets. Exposure durations were 10 ms, so under energy summation the target area was much darker than the rest. In another condition the mask was red and targets were blue, so under energy summation the target area could also be distinguished by hue. Masking magnitude increased with delay of mask onset, and it was established by four independent criteria that integration was negligible in the condition which produced most masking. It is deduced that integration is not necessary for masking; furthermore it is suggested that integration never produces masking, but rather may or may not protect from a disruptive effect of interruption. The argument is that were the visual system to have better visual resolution, it would suffer more given the same masking parameters. It is argued that type B masking functions arise from a combination of the facilitatory effect of integration and the detrimental effect of interruption.

1961 ◽  
Vol 201 (5) ◽  
pp. 965-967 ◽  
Author(s):  
Harry J. Carlisle ◽  
Robert W. Reynolds

An examination was made of the role of the area postrema in the regulation of food intake and in mediating the anorexigenic effect of amphetamine. Rats with area postrema lesions lost 13–20% of preoperative weight, and tended to regain only a slight amount of this lost weight. Control lesions in the hippocampus and dorsolateral thalamus produced no significant effect on food intake. It was concluded that the area postrema has a facilitatory effect on food intake. The anorexigenic effect of amphetamine was exaggerated in the area postrema group with 50% or greater damage to the target area only. This area is not, therefore, a primary receptor for amphetamine, but is somehow implicated, since its destruction results in greater drug action.


2017 ◽  
pp. 148-159
Author(s):  
V. Papava

This paper analyzes the problem of technological backwardness of economy. In many mostly developing countries their economies use obsolete technologies. This can create the illusion that this or that business is prosperous. At the level of international competition, however, it is obvious that these types of firms do not have any chance for success. Retroeconomics as a theory of technological backwardness and its detrimental effect upon a country’s economy is considered in the paper. The role of the government is very important for overcoming the effects of retroeconomy. The phenomenon of retroeconomy is already quite deep-rooted throughout the world and it is essential to consolidate the attention of economists and politicians on this threat.


2013 ◽  
Vol 1 (1) ◽  
pp. 10
Author(s):  
Noar Muda Satyawan ◽  
Shelly Tutupoho ◽  
Yusli Wardiatno ◽  
Makoto Tsuchiya

Erosion rate on corals due to activities of other biota is called bioerosion. The rock-boring urchin, Echinometra mathaei, when it is abundant, plays a significant role in benthic ecosystems, including biological processes like coral erosion. During feeding, E. mathaei erodes calcium carbonate besides grazing on algae living on coral, so it plays an important role in both organic and inorganic carbons in coral reefs. The urchin E. mathaei actively feeds during the night time (nocturnal grazer). Although in Okinawa four types (A-D) of the urchin exist, the research only focused on the types A and B. Type A of E. mathaei produced 0.44951 g feces per day on average while type B produced 0.38030 g feces per day. CaCO3 analysis in feces and gut contents showed bioerosion rate of E. mathaei type A was 0.64492 g/individu/day, and 0.54436 g/individu/day in type B. There were no significant differences in bioerosion impact of E. mathaei type A and B© Laju erosi pada karang yang disebabkan oleh biota, dikenal dengan bioerosi. Bulu babi jenis Echinometra mathaei, ketika melimpah, menjadi sangat berpengaruh terhadap ekosistem bentik termasuk proses biologi seperti erosi karang. Selama aktivitas makan, E. mathaei menggerus kalsium karbonat dalam proporsi yang besar di samping alga yang tumbuh menempel pada karang sehingga memiliki peran penting dalam siklus karbon organik dan anorganik di ekosistem terumbu karang. Bulu babi E. mathaei aktif mencari makan pada malam hari (nocturnal grazer). Meskipun di Okinanawa ada 4 tipe (A-D), pada eksperimen kali ini memfokuskan pada tipe A dan B saja. Tipe A E. mathaei rata-rata memproduksi 0,44951 g feses/hari dan tipe B memproduksi 0,38030 g feses/hari. Berdasarkan analisis CaCO3 yang dilakukan pada feses dan isi lambung, laju bioerosi yang disebabkan oleh E. mathaei tipe A sebesar 0,64492 g/individu/hari sedangkan tipe B sebesar 0,54436 g/individu/hari. Tidak terdapat perbedaan dampak bioerosi yang signifikan antara E. mathaei tipe A dan B©


2017 ◽  
Vol 7 (2) ◽  
pp. 7-25
Author(s):  
Karolina Diallo

Pupil with Obsessive-Compulsive Disorder. Over the past twenty years childhood OCD has received more attention than any other anxiety disorder that occurs in the childhood. The increasing interest and research in this area have led to increasing number of diagnoses of OCD in children and adolescents, which affects both specialists and teachers. Depending on the severity of symptoms OCD has a detrimental effect upon child's school performance, which can lead almost to the impossibility to concentrate on school and associated duties. This article is devoted to the obsessive-compulsive disorder and its specifics in children, focusing on the impact of this disorder on behaviour, experience and performance of the child in the school environment. It mentions how important is the role of the teacher in whose class the pupil with this diagnosis is and it points out that it is necessary to increase teachers' competence to identify children with OCD symptoms, to take the disease into the account, to adapt the course of teaching and to introduce such measures that could help children reduce the anxiety and maintain (or increase) the school performance within and in accordance with the school regulations and curriculum.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Michael Lohse ◽  
Johannes C. Dahmen ◽  
Victoria M. Bajo ◽  
Andrew J. King

AbstractIntegration of information across the senses is critical for perception and is a common property of neurons in the cerebral cortex, where it is thought to arise primarily from corticocortical connections. Much less is known about the role of subcortical circuits in shaping the multisensory properties of cortical neurons. We show that stimulation of the whiskers causes widespread suppression of sound-evoked activity in mouse primary auditory cortex (A1). This suppression depends on the primary somatosensory cortex (S1), and is implemented through a descending circuit that links S1, via the auditory midbrain, with thalamic neurons that project to A1. Furthermore, a direct pathway from S1 has a facilitatory effect on auditory responses in higher-order thalamic nuclei that project to other brain areas. Crossmodal corticofugal projections to the auditory midbrain and thalamus therefore play a pivotal role in integrating multisensory signals and in enabling communication between different sensory cortical areas.


Author(s):  
Ayşe I. Kural ◽  
Berrin Özyurt

Research has demonstrated consistently that personality and perceived stress, independently, are essential factors for university adjustment among university freshmen; however, little is known about the associations between personality, perceived stress, and adjustment together. Our primary goal was to explore the predictive utility of perceived stress for explaining university adjustment among university freshmen ( N = 290). We also tested the moderating role of personality traits and this research was embedded within a Big Five model of personality including the sixth trait for Turkish context, ‘Negative Valence’. Results addressed that only conscientiousness and negative valence moderated the perceived stress and adjustment association. Students high on negative valence and/or conscientiousness tended to experience the detrimental effect of perceived stress on university adjustment more due to their personality. These results suggested that personality might be an important factor to include in adjustment fostering interventions for freshmen at universities.


1995 ◽  
Vol 182 (5) ◽  
pp. 1415-1421 ◽  
Author(s):  
T C Wu ◽  
A Y Huang ◽  
E M Jaffee ◽  
H I Levitsky ◽  
D M Pardoll

Introduction of the B7-1 gene into murine tumor cells can result in rejection of the B7-1 transductants and, in some cases, systemic immunity to subsequent challenge with the nontransduced tumor cells. These effects have been largely attributed to the function of B7-1 as a costimulator in directly activating tumor specific, major histocompatibility class I-restricted CD8+ T cells. We examined the role of B7-1 expression in the direct rejection as well as in the induction of systemic immunity to a nonimmunogenic murine tumor. B-16 melanoma cells with high levels of B7-1 expression did not grow in C57BL/6 recipient mice, while wild-type B-16 cells and cells with low B7-1 expression grew progressively within 21 d. In mixing experiments with B7-1hi and wild-type B-16 cells, tumors grew out in vivo even when a minority of cells were B7-1-. Furthermore, the occasional tumors that grew out after injection of 100% B-16 B7-1hi cells showed markedly decreased B7-1 expression. In vivo antibody depletions showed that NK1.1 and CD8+ T cells, but not CD4+ T cells, were essential for the in vivo rejection of tumors. Animals that rejected B-16 B7-1hi tumors did not develop enhanced systemic immunity against challenge with wild-type B-16 cells. These results suggest that a major role of B7-1 expression by tumors is to mediate direct recognition and killing by natural killer cells. With an intrinsically nonimmunogenic tumor, this direct killing does not lead to enhanced systemic immunity.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Chang Chen ◽  
Zhe Zhang ◽  
Ming Jia

PurposeThe purpose of this study is to examine the effect of stretch goals on unethical behavior and explore the mediating role of ambivalent identification and moderating role of competitive psychological climate.Design/methodology/approachA total of 350 MBA students from Northwestern China completed the two-phase survey. The bootstrapping analysis outlined by Hayes was used to assess a moderated mediation model.FindingsThis study found that stretch goals could trigger employees' unethical behavior via ambivalent identification. Competitive psychological climate intensified the relationship between stretch goals and ambivalent identification. Moreover, such a climate aggravated the indirect effect of stretch goals on unethical behavior via ambivalent identification.Practical implicationsOrganizations and managers should use stretch goals prudently and implement measures to reduce the ethical cost.Originality/valueThis study provides unique contributions by identifying ambivalent identification as an important mediator and competitive psychological climate as a boundary condition of stretch goals' disruptive effect on unethical behavior.


Development ◽  
1994 ◽  
Vol 120 (6) ◽  
pp. 1643-1649 ◽  
Author(s):  
K.H. Herzog ◽  
K. Bailey ◽  
Y.A. Barde

Using a sensitive and quantitative method, the mRNA levels of brain-derived neurotrophic factor (BDNF) were determined during the development of the chick visual system. Low copy numbers were detected, and BDNF was found to be expressed in the optic tectum already 2 days before the arrival of the first retinal ganglion cell axons, suggesting an early role of BDNF in tectal development. After the beginning of tectal innervation, BDNF mRNA levels markedly increased, and optic stalk transection at day 4 (which prevents subsequent tectal innervation) was found to reduce the contralateral tectal levels of BDNF mRNA. Comparable reductions were obtained after injection of tetrodotoxin into one eye, indicating that, already during the earliest stages of target encounter in the CNS, the degree of BDNF gene expression is influenced by activity-dependent mechanisms. BDNF mRNA was also detected in the retina itself and at levels comparable to those found in the tectum. Together with previous findings indicating that BDNF prevents the death of cultured chick retinal ganglion cells, these results support the idea that the tightly controlled expression of the BDNF gene might be important in the co-ordinated development of the visual system.


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