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61.
Davide Rigoni David Polezzi Rino Rumiati Ramona Guarino Giuseppe Sartori 《Brain research bulletin》2010,81(4-5):445-452
In the present study, we showed that, in a social gambling task, individuals are influenced more by the type of social interaction than by the pattern of gains and losses. More precisely, the neural responses, as well as the level of pleasantness/unpleasantness following gains and losses, are modulated by social interaction factors.Here we present an Event-Related Potentials (ERPs) study in which three groups of participants were compared. Subjects were engaged in gambling tasks differing with regard to social factors: in a first condition, there was no social context; in a second condition, participants compared their outcomes with those of another individual; in a third condition, participants competed for a limited amount of money with another contender. In all conditions, all participants were revealed the outcome of an unselected alternative (non-obtained outcome) prior to the payoff associated with their selected option (obtained outcome). In addition, affective ratings were measured after the outcomes were presented.In the group without social context, ERPs results replicated previous findings. Interestingly, the P200 was modulated by varying social contexts, suggesting that attentive resources allocated to payoffs in comparison and competitive situations are decreased presumably in favor of social cues. Furthermore, Feedback Related Negativity (FRN) was predictive of the subjective feeling of pleasantness/unpleasantness following monetary outcomes.The present data provide information about neural and cognitive processing underlying economic decision-making when other individuals are involved. 相似文献
62.
MA Islam RI Chowdhury N Chakraborty W Bari HH Akhter 《The European journal of contraception & reproductive health care》2013,18(4):203-213
Objectives There are only a few studies on maternal morbidity, delivery complications and maternal mortality in Bangladesh. This study analyzes data from a follow-up study conducted by the Bangladesh Institute of Research for Health and Technologies (BIRPERHT) on maternal morbidity in rural Bangladesh in 1993. Methods A total of 1020 pregnant women were interviewed in the follow-up component of the study. The survey collected information on socioeconomic and demographic characteristics, pregnancy-related care and practice, morbidity during the period of follow-up as well as in the past, information concerning complications at the time of delivery and during the postpartum period. For the purpose of this study, we selected 993 pregnant women with at least one antenatal follow-up. Both bivariate and multivariate analyses were conducted to identify the potential risk factors for complication during delivery and duration of labor. Results and conclusions It appears that complications during the antenatal period can result in various complications at the time of delivery. Some of the important findings are: hemorrhage during the antenatal period increases the risk of excessive hemorrhage during delivery, the risk of obstructed labor increases significantly if abdominal pain is observed during the antenatal period, prolonged labor appears to be significantly higher for the first pregnancy, and pregnancies suffering from abdominal pain during pregnancy tend to have a higher risk of prolonged labor during delivery. The duration of labor appears to be negatively associated with the number of previous pregnancies, being longest for the first pregnancies. The duration of labor pain is significantly higher for the respondents who reported the index pregnancy as undesired, and, similarly, the respondents who were reported to be involved with gainful employment would have a shorter duration of labor pain than those having no involvement with gainful employment. 相似文献
63.
64.
Everything else being the same, an equal outcome is generally preferred; however, an equitable allocation sometimes is possible only by sacrificing the total amount of resources available to society. Moreover, direct interests may interact with the perception of equality. Here, we have investigated individual preferences, and their neural basis, by employing a task in which an allocation of a fixed amount between the subject and another person (MS condition) or two third parties (TP condition) is randomly determined. The subject can accept or reject the outcome, in the same fashion as the Ultimatum Game: thus an unequal offer may be rejected at the cost of a loss in total amount. Behavioral results show preference for equal outcomes in TP and for equal and advantageous outcomes in MS. An activation of medial prefrontal cortex (mPFC), extending to the anterior middle cingulate cortex (aMCC), was found in MS unequal outcomes, particularly for disadvantageous outcomes and consequent rejections. The anterior insula (AI) was active for unequal outcomes, in both MS and TP. We propose that the equal treatment is a default social norm, and its violation is signaled by the AI, whereas aMCC/mPFC activation, negatively correlated to rejections, reflects the effort to overcome the default rule of equal treatment in favor of a self-advantageous efficiency. 相似文献
65.
David Polezzi Giuseppe Sartori Rino Rumiati Giulio Vidotto Irene Daum 《NeuroImage》2010,49(2):1886-1894
Understanding the neurocognitive basis of risk-taking behavior is an important issue, especially in economic decision-making. Classical behavioral studies have shown that risk-attitude changes across different contexts, but little is so far known about the brain correlates of processing of outcomes across such context shifts. In this study, EEG was recorded while subjects performed a gambling task. Participants could choose between a risky and a safer option, within two different contexts: one in which options yielded gains and losses of the same magnitude (Zero Expected Value context) and another in which gains were larger than losses (Positive Expected Value context). Based on their risk-attitude, two groups were compared: subjects who are risk-seekers in the zero Expected Value context (Zero-Oriented group) and subjects who are risk-seekers in the positive Expected Value condition (Positive-Oriented group). The Feedback Related Negativity (FRN) reflects this distinction, with each group being insensitive to magnitude of outcomes in the condition in which they were risk-prone. P300 amplitude mirrored the behavioral results, with larger amplitudes in the condition in which each group showed a higher risk-tendency. Source analyses highlighted the involvement of posterior cingulate cortex in risky decision-making. Taken together, the findings make a contribution to the clarification of the neurocognitive substrates of risky decision-making. 相似文献
66.
67.
Intracranial meningiomas: high-field MR imaging 总被引:6,自引:0,他引:6
Spagnoli MV; Goldberg HI; Grossman RI; Bilaniuk LT; Gomori JM; Hackney DB; Zimmerman RA 《Radiology》1986,161(2):369
68.
Magnetic resonance (MR) imaging of jugular venous thrombosis was investigated in three patients who had symptoms suggestive of this condition; the diagnosis was later confirmed by computed tomography, by venography, and clinically. Bright intraluminal signal intensity was seen throughout the course of the affected jugular vein on MR images in all three patients, in sharp contrast to the lack of signal from the corresponding site in the uninvolved venous system. Temporal changes in signal intensity from the acute to subacute stage of thrombosis were evaluated for one patient. A relative increase in signal intensity for the subacute phase was believed to be related to a decrease in the T1 relaxation time. MR may be the imaging modality of choice in the investigation of venous thrombosis. 相似文献
69.
Ocular and orbital lesions: surface coil MR imaging 总被引:1,自引:0,他引:1
Bilaniuk LT; Schenck JF; Zimmerman RA; Hart HR Jr; Foster TH; Edelstein WA; Goldberg HI; Grossman RI 《Radiology》1985,156(3):669-674
Nine lesions, four ocular (three melanomas, one hemangioma) and five orbital (two perioptic meningiomas, one hemangioma, one pseudotumor, one mucocele), were evaluated by magnetic resonance surface coil imaging at 1.5 T. Small ocular lesions with 3.9-4.5-mm-elevation were demonstrated. The use of two different pulse sequences resulted in separation of melanoma from adjacent retinal detachment. Contrast obtained between orbital lesions and the adjacent normal structures was better than that demonstrated with high-resolution computed tomography. 相似文献
70.
Cerebral vasculitis: MR imaging and angiographic correlation 总被引:20,自引:0,他引:20