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1.
The Iowa Gambling Task (IGT) developed by Bechara et al. in 1994 is used to diagnose patients with Ventromedial Medial Prefrontal Cortex (VMPFC) lesions, and it has become a landmark in research on decision making. According to Bechara et al., the manipulation of progressive increments of monetary value can normalize the performance of patients with VMPFC lesions; thus, they developed a computerized version of the IGT. However, the empirical results showed that patients'' performances did not improve as a result of this manipulation, which suggested that patients with VMPFC lesions performed myopically for future consequences. Using the original version of the IGT, some IGT studies have demonstrated that increments of monetary value significantly influence the performance of normal subjects in the IGT. However, other research has resulted in inconsistent findings. In this study, we used the computerized IGT (1X-IGT) and manipulated the value contrast of progressive increments (i.e., by designing the 10X-IGT, which contained 10 times of progressive increment) to investigate the influence of value contrast on the performance of normal subjects. The resulting empirical observations indicated that the value contrast (1X- vs. 10X-IGT) of the progressive increment had no effect on the performance of normal subjects. This study also provides a discussion of the issue of value in IGT-related studies. Moreover, we found the “prominent deck B phenomenon” in both versions of the IGT, which indicated that the normal subjects were guided mostly by the gain-loss frequency, rather than by the monetary value contrast. In sum, the behavioral performance of normal subjects demonstrated a low correlation with changes in monetary value, even in the 10X-IGT.  相似文献   

2.
Studies indicated that people behave less responsibly after exposure to information containing deterministic statements as compared to free will statements or neutral statements. Thus, deterministic primes should lead to enhanced risk-taking behavior. We tested this prediction in two studies with healthy participants. In experiment 1, we tested 144 students (24 men) in the laboratory using the Iowa Gambling Task. In experiment 2, we tested 274 participants (104 men) online using the Balloon Analogue Risk Task. In the Iowa Gambling Task, the free will priming condition resulted in more risky decisions than both the deterministic and neutral priming conditions. We observed no priming effects on risk-taking behavior in the Balloon Analogue Risk Task. To explain these unpredicted findings, we consider the somatic marker hypothesis, a gain frequency approach as well as attention to gains and / or inattention to losses. In addition, we highlight the necessity to consider both pro free will and deterministic priming conditions in future studies. Importantly, our and previous results indicate that the effects of pro free will and deterministic priming do not oppose each other on a frequently assumed continuum.  相似文献   

3.
Prior to age four, children succeed in non-elicited-response false-belief tasks but fail elicited-response false-belief tasks. To explain this discrepancy, the processing-load account argues that the capacity to represent beliefs emerges in infancy, as indicated by early success on non-elicited-response tasks, but that children’s ability to demonstrate this capacity depends on the processing demands of the task and children’s processing skills. When processing demands exceed young children’s processing abilities, such as in standard elicited-response tasks, children fail despite their capacity to represent beliefs. Support for this account comes from recent evidence that reducing processing demands improves young children’s performance: when demands are sufficiently reduced, 2.5-year-olds succeed in elicited-response tasks. Here we sought complementary evidence for the processing-load account by examining whether increasing processing demands impeded children’s performance in a non-elicited-response task. 3-year-olds were tested in a preferential-looking task in which they heard a change-of-location false-belief story accompanied by a picture book; across children, we manipulated the amount of linguistic ambiguity in the story. The final page of the book showed two images: one that was consistent with the main character’s false belief and one that was consistent with reality. When the story was relatively unambiguous, children looked reliably longer at the false-belief-consistent image, successfully demonstrating their false-belief understanding. When the story was ambiguous, however, this undermined children’s performance: looking times to the belief-consistent image were correlated with verbal ability, and only children with verbal skills in the upper quartile of the sample demonstrated a significant preference for the belief-consistent image. These results support the processing-load account by demonstrating that regardless of whether a task involves an elicited response, children’s performance depends on the processing demands of the task and their processing skills. These findings also have implications for alternative, deflationary accounts of early false-belief understanding.  相似文献   

4.
Females of Nasonia vitripennis were maintained in light cycles from 12 to 72 hr in length, with 4 to 28 hr photoperiods, and their offspring examined for larval diapause. This ‘resonance’ technique revealed periodic maxima of diapause induction, about 24 hr apart. The ‘ascending slopes’ of these maxima appeared to obtain their principal time cue from dusk and the ‘descending slopes’ from dawn. This suggests that two independent—dawn and dusk—oscillators are involved in the Nasonia photoperiodic clock. The results are interpreted in terms of ‘internal coincidence’.N. vitripennis was shown to be able to distinguish between 12 and 18 hr of red light (>600 nm) in the photoperiodic sense. A ‘positive’ resonance experiment using such a red light was also performed. This shows that the spectral sensitivity of the pigment coupling the circadian system to the environmental light cycle extends into the red end of the spectrum.  相似文献   

5.
Summary In a three-generation family, the segregation of an apparent silent allele at the GLO I locus in association with the rare HLA haplotype AW30-CW4-BW35 was observed in four members. In two cases the assumption of homozygosity at the GLO locus would lead to mother-child exclusions. Phenotypically, the GLO activity in the GLO 0 carriers is clearly diminished.With rechnical assistance of Mrs. C. Walter and Mrs. M. MuellerSupported by the Deutsche Forschungsgemeinschaft (Ri 164/12)  相似文献   

6.
《Ethnos》2012,77(2):227-251
In Eastern Christianity novitiate is a period of learning to experience the presence of God in one's life and the world. Novices follow the hesychast prayer, a mystical tradition that leads them to an experiential knowledge of God. In this paper, I argue that novitiate should be regarded as a complex learning process involving specific assemblages of contextual, cognitive, body-sensory and emotional aspects. By educating their attention and emotion novices learn to see beyond and within reality and thus discover the potentiality of people and things ‘in the likeness of God’. Religious transmission happens not only through embodied practice and the active acquisition of religious knowledge but, more importantly, through the work of the imagination. Novices' orientation towards the transcendent requires an expansion of the imaginative capacities beyond their ‘routine’ functioning. Imagination could be thus seen as a key cognitive capacity through which they learn to experience God.  相似文献   

7.
‘Young’ human red cells are shown to possess a specific K+ pathway which is dependent on Cl and sensitive to cell volume. This system was latent in ‘mature’ cells but was revealed by high hydrostatic pressure. This suggests the pathway is functionally active in ‘young’ cells but becomes masked with cell maturation.  相似文献   

8.
This paper is concerned with a Filipino psychic surgeon confronted by a particularly challenging case of a kind perhaps unprecedented in his practice. The paper describes and analyzes how the practitioner modified his usual clinical performance and adapted his actions to demands of an extremely difficult situation. The case is viewed in wider perspective relative to the significance of performative acts of healing in a pluralistic medical setting.  相似文献   

9.
Sequences encoding the immunoglobulin heavy-chain variable (VH) domains were engineered in a new general purpose vector to transform plants via Agrobacterium. The expression of an isolated VH domain (IVD) after introduction into the plant genome has been monitored by northern, western and immuno-histochemical analysis. Immunoblotting showed that the polypeptide was stably expressed and accounted for up to 1% of the soluble protein fraction. It is therefore proposed that single immunoglobulin domains of suitable specificity expressed in plants may constitute an effective system to inhibit the activity of molecules involved in plant pathology or plant development.  相似文献   

10.
Several theories propose that the cortex implements an internal model to explain, predict, and learn about sensory data, but the nature of this model is unclear. One condition that could be highly informative here is Charles Bonnet syndrome (CBS), where loss of vision leads to complex, vivid visual hallucinations of objects, people, and whole scenes. CBS could be taken as indication that there is a generative model in the brain, specifically one that can synthesise rich, consistent visual representations even in the absence of actual visual input. The processes that lead to CBS are poorly understood. Here, we argue that a model recently introduced in machine learning, the deep Boltzmann machine (DBM), could capture the relevant aspects of (hypothetical) generative processing in the cortex. The DBM carries both the semantics of a probabilistic generative model and of a neural network. The latter allows us to model a concrete neural mechanism that could underlie CBS, namely, homeostatic regulation of neuronal activity. We show that homeostatic plasticity could serve to make the learnt internal model robust against e.g. degradation of sensory input, but overcompensate in the case of CBS, leading to hallucinations. We demonstrate how a wide range of features of CBS can be explained in the model and suggest a potential role for the neuromodulator acetylcholine. This work constitutes the first concrete computational model of CBS and the first application of the DBM as a model in computational neuroscience. Our results lend further credence to the hypothesis of a generative model in the brain.  相似文献   

11.
Abstract

This paper explores how the creation of a socially and ethnically mixed student body relates to mobility within the context of Beaumont Academy. This authoritarian school opened in 2004 under the ethos ‘structure liberates’. Based in a predominantly deprived, ethnic minority area of London, Beaumont seeks to culturally transform its students. With its outstanding GCSE results, the school has been championed as a blueprint for reform, yet the cultural implications underlying this approach remain unexamined. The ethos pathologizes the surrounding area while essentializing itself as an ‘oasis in the desert’ liberating students through discipline. The paper explores how mobility is embodied by students and the alterations or eliminations necessary to achieve it. These alterations produce raced and classed positions and bring them into focus, highlighting who needs to ‘adjust’ themselves to accrue value. Uncritical celebrations of mixed-ness conceal structural inequalities lingering beneath the rhetoric of happy multiculturalism and aspirational citizenship. These inequalities are exacerbated by a marketized education system.  相似文献   

12.
We studied patients with idiopathic Parkinson’s disease (PD) from an isolated population in the Netherlands aiming to map gene(s) involved in PD susceptibility. A total of 109 parkinsonism patients were independently ascertained, of whom 62 presented late-onset, idiopathic PD. Genealogical research showed that 45 index cases with idiopathic PD were linked to a common ancestor, indicating familiar clustering among the patients. This strong familial clustering was highly significant (P=0.005) when compared to random controls from the same population. We performed a genome wide scan using 382 polymorphic markers in 44 distantly related PD patients plus 112 unaffected first-degree relatives and spouses. Our genome wide association analysis (DISLAMB) revealed evidence of association at a nominal P-value<0.01 for markers D2S2333, D4S405, D9S158, D13S153. Other regions on chromosomes 3p, 4q, 14q, 17p and 17q were found at a significance level of P<0.05. In a follow-up study, we investigated all the positive regions using a denser marker set and a larger sample (total of 630 individuals including all late-onset PD patients). The strongest evidence for association remained for the 9q and 14q region. A significant association was found for marker D9S1838 (OR=2.0, 95% CI 1.1–3.5, P=0.014) and D14S65 (OR=3.2, 95% CI 1.7–6.1, P<0.001). Moreover, a common haplotype with excess of sharing among late-onset PD cases was observed on both regions. Our results suggest the existence of two loci influencing PD susceptibility on chromosome 9q and 14q.  相似文献   

13.
If biological-motion point-light displays are presented upside down, adequate perception is strongly impaired. Reminiscent of the inversion effect in face recognition, it has been suggested that the inversion effect in biological motion is due to impaired configural processing in a highly trained expert system. Here, we present data that are incompatible with this view. We show that observers can readily retrieve information about direction from scrambled point-light displays of humans and animals. Even though all configural information is entirely disrupted, perception of these displays is still subject to a significant inversion effect. Inverting only parts of the display reveals that the information about direction, as well as the associated inversion effect, is entirely carried by the local motion of the feet. We interpret our findings in terms of a visual filter that is tuned to the characteristic motion of the limbs of an animal in locomotion and hypothesize that this mechanism serves as a general detection system for the presence of articulated terrestrial animals.  相似文献   

14.
The ''Positive Effect'' is defined as the phenomenon of preferential cognitive processing of positive affective information, and avoidance or dismissal of negative affective information in the social environment. The ‘Positive Effect’ is found for older people compared with younger people in western societies and is believed to reflect a preference for positive emotional regulation in older adults. It is not known whether such an effect is Universal, and in East Asian cultures, there is a highly controversial debate concerning this question. In the current experiment we explored whether Chinese older participants showed a ''Positive Effect'' when they inspected picture pairs that were either a positive or a negative picture presented with a neutral picture, or a positive and negative picture paired together. The results indicated that both groups of participants showed an attentional bias to both pleasant (more processing of) and unpleasant pictures (initial orienting to) when these were paired with neutral pictures. When pleasant and unpleasant pictures were paired together both groups showed an initial orientation bias for the pleasant picture, but the older participants showed this bias for initial orienting and increased processing measures, providing evidence of a ‘Positive Effect’ in older Chinese adults.  相似文献   

15.
Summary Studies of four combinations of Nicotiana involving four species, N. langsdorffii (N. l.), N. alata (N. a.), N. glutinosa (N. g.) and N. tabacum (N. t.), have shown that parthenogenetic haploid and diploid maternal individuals may arise with the use of male gametes (pollen) treated with high doses of ionising radiation in plants, similar to that found in animals (Hertwig Effect). At lower doses (10–20 Kr) rapidly diminishing numbers of seedlings were produced and many of these died soon after germination or before reaching maturity. In the intraspecific combination N. l. × N. l., viable seeds were produced only at the lower doses of 10 and 15 Kr. In the interspecific combination N. l. × N. a., at lower doses, all plants that came to bloom showed variable hybrid morphology. There were no plants resembling the female parent. In the combination N.t. × N.a., at lower doses there were rare surviving plants which were maternal dihaploid (1 plant out of 4 at 15 Kr) or tetraploid N. tabacum (all 5 plants at 20 Kr). All surviving plants at higher doses (50 and 100 Kr) were maternal tetraploids. In the combination N.t.×N.g., plants produced at lower than 20 Kr were almost all either aneuploid or triploid hybrids. Dihaploid, maternal N. tabacum plants appeared at 20 Kr and higher doses. After 50 Kr the large proportion of plants produced were maternal dihaploid or tetraploid N. tabacum.  相似文献   

16.
17.
Vesicles, generally defined as self-assembled structures formed by single or multiple concentric bilayers that surround an aqueous core, have been widely used for biomedical applications. They can either occur naturally (e.g. exosomes) or be produced artificially and range from the micrometric scale to the nanoscale. One the most well-known vesicle is the liposome, largely employed as a drug delivery nanocarrier. Liposomes have been modified along the years to improve physicochemical and biological features, resulting in long-circulating, ligand-targeted and stimuli-responsive liposomes, among others. In this process, new nomenclatures were reported in an extensive literature. In many instances, the new names suggest the emergence of a new nanocarrier, which have caused confusion as to whether the vesicles are indeed new entities or could simply be considered modified liposomes. Herein, we discussed the extensive nomenclature of vesicles based on the suffix “some” that are employed for drug delivery and composed of various types and proportions of lipids and others amphiphilic compounds. New names have most often been selected based on changes of vesicle lipid composition, but the payload, structural complexity (e.g. multicompartment) and new/improved proprieties (e.g. elasticity) have also inspired new vesicle names. Based on this discussion, we suggested a rational classification for vesicles.  相似文献   

18.
A newly isolated porcine glucagon-like biologically active intestinal peptide (enteroglucagon) has been tested for its ability to stimulate the cyclic AMP system present in different tissue preparations from the rat: membranes prepared from liver or from isolated fundic glands as well as intact glands isolated from either the fundus or the antrum. Enteroglucagon (EG) was about l0 times less potent than pancreatic glucagon (G) in liver membranes, whereas it was about 20 times more potent than G in fundic membranes as well as in fundic glands, where it acts at doses as low as 3 × 10-10 M. EG and G were practically ineffective in antral glands. It is concluded that EG is an under-glucagon in rat liver, whereas it is a super-glucagon in rat fundic glands. Accordingly, we propose to call this peptide 'oxyntomodulin'.  相似文献   

19.
In the past 15 years, fragment-based lead discovery (FBLD) has been adopted widely throughout academia and industry. The approach entails discovering very small molecular fragments and growing, merging, or linking them to produce drug leads. Because the affinities of the initial fragments are often low, detection methods are pushed to their limits, leading to a variety of artifacts, false positives, and false negatives that too often go unrecognized. This Digest discusses some of these problems and offers suggestions to avoid them. Although the primary focus is on FBLD, many of the lessons also apply to more established approaches such as high-throughput screening.  相似文献   

20.
Discerning the intricacies of mating systems in butterflies can be difficult, particularly when multiple mating strategies are employed and are cryptic and not exclusive. We observed the behavior and habitat use of 113 male Taylor’s checkerspot butterflies (Euphydryas editha taylori). We confirmed that two distinct mating strategies were exhibited; patrolling and perching. These strategies varied temporally in relation to the protandrous mating system employed. Among perching males, we recorded high site fidelity and aggressive defense of small (<5 m2) territories. This territoriality was not clearly a function of classic or non-classic resource defense (i.e., host plants or landscape), but rather appeared to constitute guarding of female pupae (virgin females). This discrete behavior is previously undocumented for this species and has rarely been observed in butterflies.  相似文献   

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