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91.
B D Gold 《Adolescence》1987,22(87):535-544
The purpose of this study was to provide some understanding of punk rockers. Although they have received media attention in the depiction of their unusual hair and clothing styles, there is limited information about their personalities. In this study a delinquent group of punk rockers was compared with a delinquent group of nonpunk rockers on self-image, a personality factor related to teenagers' mental health and adjustment. Each group consisted of 20 subjects, 15 males and 5 females, aged 14 to 17. Subjects were administered a Screening Questionnaire, the Offer Self-Image Questionnaire (OSIQ), and the California Psychological Inventory (CPI) while detained at a Southern California juvenile hall. Interest in the CPI was focused on the Socialization (So) scale. A one-way analysis of variance was conducted on each of the five OSIQ dimensions. No significant differences were found between the groups. The importance of these findings is that even though punk rockers may look and act unusual, they may actually be similar to other groups. Due to possibly invalid CPI test protocols a t test and content analysis of the CPI So scale was conducted. The t test was significant and the chi-square analyses were significant on two questions of the CPI So scale. This suggests that there may be differences between the groups in terms of family dynamics. Professionals can utilize these findings in their work with this misunderstood segment of society.  相似文献   
92.
Previous studies using aversive training tasks have reported that retention is enhanced by post-training administration of epinephrine. This study investigated the effects of post-training administration of epinephrine on retention of an appetitive task. The results indicate that epinephrine can enhance retention performance in an appetitive task of both rats and mice. Pretraining injections of propranolol and phenoxybenzamine, alpha- and beta-adrenergic receptor antagonists, attenuate the memory-enhancing effects of epinephrine. These results are consistent with the view that release of peripheral epinephrine may regulate storage of new information and may mediate memory modulation produced by a variety of treatments.  相似文献   
93.
The results of previous studies indicate that the extent of a transient decline in brain norepinephrine (NE) levels shortly after training and administration of any of several memory modulating treatments is correlated with later retention performance. The present experiment assessed such changes after one-trial inhibitory (passive) avoidance training and, in addition, measured concentration changes in 3-methoxy-4-hydroxyphenylglycol (MHPG), the major metabolite of brain NE, as well as dopamine (DA) and epinephrine (EPI) levels. The results indicate that the decreases in brain NE after footshock are accompanied by an increase in MHPG, thus providing additional evidence that brain NE is released after training. DA levels were unchanged after training; brainstem EPI levels increased after the training footshock, but forebrain EPI levels were unchanged. A second experiment examined brain catecholamine levels in animals which received post-training electrical stimulation of the amygdala. The findings of this experiment indicate that the amygdala damage which accompanies electrode implantation apparently results in a chronic change in whole brain NE levels and metabolism. After amygdala, NE concentrations in both brainstem and forebrain samples were reduced by 20% and MHPG was increased by 22-34%. Furthermore, NE levels were not responsive to training in implanted animals. Thus, brain NE levels after training were not predictive of retention performance in amygdala-implanted or -stimulated animals. However, the significance of such findings for understanding the possible role of central NE in memory storage is complicated by the severe modification of the dynamics of brain aminergic systems in animals bearing amygdala electrodes.  相似文献   
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Individuals from across the psychosis spectrum display impairments in reinforcement learning. In some individuals, these deficits may result from aberrations in reward prediction error (RPE) signaling, conveyed by dopaminergic projections to the ventral striatum (VS). However, there is mounting evidence that VS RPE signals are relatively intact in medicated people with schizophrenia (PSZ). We hypothesized that, in PSZ, reinforcement learning deficits often are not related to RPE signaling per se but rather their impact on learning and behavior (i.e., learning rate modulation), due to dysfunction in anterior cingulate and dorsomedial prefrontal cortex (dmPFC). Twenty-six PSZ and 23 healthy volunteers completed a probabilistic reinforcement learning paradigm with occasional, sudden, shifts in contingencies. Using computational modeling, we found evidence of an impairment in trial-wise learning rate modulation (α) in PSZ before and after a reinforcement contingency shift, expressed most in PSZ with more severe motivational deficits. In a subsample of 22 PSZ and 22 healthy volunteers, we found little evidence for between-group differences in VS RPE and dmPFC learning rate signals, as measured with fMRI. However, a follow-up psychophysiological interaction analysis revealed decreased dmPFC-VS connectivity concurrent with learning rate modulation, most prominently in individuals with the most severe motivational deficits. These findings point to an impairment in learning rate modulation in PSZ, leading to a reduced ability to adjust task behavior in response to unexpected outcomes. At the level of the brain, learning rate modulation deficits may be associated with decreased involvement of the dmPFC within a greater RL network.  相似文献   
97.
国内医疗人工智能研究日益增多,具有多学科合作,并以数据驱动的特点。走访深圳开展健康领域人工智能研发的企业、医疗机构以及研究机构的开发者,了解到存在监管不足、数据收集及处理过程欠缺标准化、责任不清等挑战。并且,面临应该如何遵循医学科研伦理审查原则,如何合法合规收集、利用、共享数据并界定责任等问题。从医院进行伦理审查实践层面探讨医疗人工智能的研究价值、科学有效性、风险受益等的审查要点;医疗人工智能研究的法律考量主要包括个人信息收集和利用的边界,以及侵权责任主体的认定。  相似文献   
98.
本研究运用问卷法与DNA分型技术,对1063名青少年(初次测评年龄为12.32±0.47岁,50.3%女生)进行间隔2年的追踪调查,考察DRD2基因TaqIA多态性与同伴身体侵害和关系侵害对青少年早期抑郁的交互作用及其性别差异。结果发现,TaqIA多态性与身体侵害、关系侵害均对男青少年抑郁存在显著的交互作用。在携带A2A2基因型的男生中,身体侵害和关系侵害可以显著正向预测其抑郁水平,而在携带A1等位基因的男生中,同伴侵害对抑郁无预测作用。此外,TaqIA多态性与身体侵害、关系侵害对女生抑郁均无显著交互作用。研究结果提示,同伴侵害是一种重要的候选环境指标,与TaqIA多态性交互影响青少年早期抑郁,并且性别在这一基因×环境交互作用中起到重要的调节效应。  相似文献   
99.
近年来,随着对滥用抗生素所引起的细菌耐药性和二重感染的认识的逐步深入,预防性应用抗生素在临床上越来越受到限制.但由于早产儿感染的临床隐匿性和易并发严重并发症等特点,预防早产儿感染的发生和进一步的发展,就显得尤为重要.通过对早产儿发生感染的易感因素、感染诱因和临床特点的分析研究,来探讨早产儿临床预防应用抗生素的必要性、合理性及临床决策思路.  相似文献   
100.
采用班级整群抽样法选取1847名3~6年级小学生(男生987名;平均年龄10.73±1.16岁)及其家长为被试,采用问卷法考察父母心理控制与小学生欺负行为的关系,同时探讨敌意归因和冷酷无情的中介作用。结果发现:(1)父母心理控制显著正向预测小学生的欺负行为;(2)冷酷无情在父母心理控制与小学生欺负行为间的关系中存在中介作用,敌意归因不发挥中介作用;(3)父母心理控制对小学生欺负行为影响的中介机制不存在显著的性别差异和学段差异。本研究结果表明,冷酷无情是父母心理控制影响小学生欺负行为的重要机制,但敌意归因不是。研究者和实践者应注重对欺负者情感加工能力的关注和干预。  相似文献   
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