环境雌激素双酚A对成年小鼠学习记忆和突触结构的影响*

双酚A (bisphenol, BPA)是一种广泛存在的环境内分泌干扰物,它可与雌激素受体结合干扰内源性雌激素对中枢神经系统的调控作用。本研究通过将10周龄小鼠灌胃染毒BPA (0.4、4、40 mg/kg/day)3个月,研究长期BPA暴露对成年小鼠记忆行为和突触可塑性的影响。开场行为测试结果表明, BPA (0.4、4、40 mg/kg/day)增加雄性的站立次数和理毛频率, BPA (4 mg/kg/day)却显著减少雌鼠的站立次数。水迷宫和被动回避行为模型检测显示, BPA主要损伤雄鼠的空间学习记忆和被动回避记忆。通过制备海马CA1区超薄切片后,电镜观测发现, BPA (0.4、40 mg/kg/day)暴露降低雄鼠海马CA1区突触数密度,缩短雄鼠突触前活性带长度,减小雄鼠突触后致密体(PSD)厚度,增加雄鼠突触间隙宽度。进一步用Western blot方法检测突触前、后的标志性蛋白Synapsin I和PSD95以及兴奋性氨基酸NMDA受体NR1亚基和AMPA受体GluR1亚基蛋白的表达,发现BPA暴露致雄鼠Synapsin I、PSD95、NR1蛋白表达水平下调。而BPA对雌鼠的记忆行为、突触形态、突触蛋白和受体蛋白均没有明显作用。以上结果提示长期B PA暴露性别特异性地影响成年小鼠的活动性和探究行为,损伤雄鼠的学习记忆,这些作用可能通过下调突触蛋白和NMDA受体的表达而负性影响突触结构可塑性,最终影响雄鼠的学习记忆功能。     

Information Transmission in Young Children: When Social Information Is More Important Than Nonsocial Information

The authors’ aim was to use a highly novel open diffusion paradigm to investigate the transmission of social information (i.e., gossip) and general knowledge within 2 groups of 10- and 11-year-old children. Four children, 2 from each group, acted as a primed information source, selected on the basis of sex and dominance ranking (high or low) within the group. Each source received 1 piece of gossip and 1 piece of general knowledge from the experimenter during natural class interaction, and the information was allowed to diffuse naturally within the group. Results revealed that gossip was transmitted more frequently than knowledge, and that male sources were more likely to transmit gossip than female sources. The relationship between characteristics of the source, and characteristics of the gossip recipient, also appeared influential with the dominant male source transmitting gossip to exclusively to friends, and the nondominant male source transmitting to individuals of higher peer regard than themselves.     

A strategy for assessing closure

This paper looks at an argument strategy for assessing the epistemic closure principle. This is the principle that says knowledge is closed under known entailment; or (roughly) if S knows p and S knows that p entails q, then S knows that q. The strategy in question looks to the individual conditions on knowledge to see if they are closed. According to one conjecture, if all the individual conditions are closed, then so too is knowledge. I give a deductive argument for this conjecture. According to a second conjecture, if one (or more) condition is not closed, then neither is knowledge. I give an inductive argument for this conjecture. In sum, I defend the strategy by defending the claim that knowledge is closed if, and only if, all the conditions on knowledge are closed. After making my case, I look at what this means for the debate over whether knowledge is closed.     

Marriages and psychological distress among adult offspring of divorce: a Norwegian study

The study compares the likelihood of getting married and of getting divorced among the adult offspring of divorced parents versus the adult offspring of parents who remain married (total N = 37,230). It also compares levels of psychological distress in the two groups (total N= 22,898). Data derive from The Nord‐Trøndelag Health Study (HUNT) and population registries from Norway. Individuals with divorced parents tended to delay marriage or not marry at all. However, among those who married, there were more divorces among the offspring of divorced parents than among offspring of parents who were still married. Offspring of divorce tended to marry other offspring of divorce. These marriages were at especially high risk of dissolution. Parental divorce was particularly influential as a risk factor during the first years of marriage. Both parental divorce and the individuals’ own divorce were risk factors for psychological distress.     

Facilitation and disruption of lateralized syllable processing by unattended stimuli in the opposite visual field

The influence of lateralized unattended stimuli on the processing of attended stimuli in the opposite visual field can shed light on the nature of information that is transferred between hemispheres. On a cued bilateral task, participants tried to identify a syllable in the attended visual field, which elicits a left hemisphere (LH) advantage and different processing strategies by the two hemispheres. The same or a different syllable or a neutral stimulus appeared in the unattended field. Transmission of unattended syllable codes between hemispheres is symmetric, as revealed by equal interference for the two visual fields. The LH is more accurate than the RH in encoding unattended syllables, as indicated by facilitation in the left but not right visual field and a greater frequency of identifiable intrusions into the left than right field. However, asymmetric encoding strategies are different for attended and unattended syllables.     

Whom do children copy? Model-based biases in social learning

This review investigates the presence of young children’s model-based cultural transmission biases in social learning, arguing that such biases are adaptive and flexible. Section 1 offers five propositions regarding the presence and direction of model-based transmission biases in young children’s copying of a model. Section 2 discusses the cognitive abilities required for differing model-based biases and tracks their development in early childhood. Section 3 suggests future areas of research including considering the social aspect of model-based biases and understanding their use within a comparative perspective.     

Bearing the unbearable: ancestral transmission through dreams and moving metaphors in the analtyic field

Abstract: This paper explores how untold and unresolved intergenerational trauma may be transmitted through unconscious channels of communication, manifesting in the dreams of descendants. Unwitting carriers for that which was too horrific for their ancestors to bear, descendants may enter analysis through an unconscious need to uncover past secrets, piece together ancestral histories before the keys to comprehending their terrible inheritance die with their forebears. They seek the relational containment of the analytic relationship to provide psychological conditions to bear the unbearable, know the unknowable, speak the unspeakable and redeem the unredeemable. In the case of ‘Rachael’, initial dreams gave rise to what Hobson (1984) called ‘moving metaphors of self’ in the analytic field. Dream imagery, projective and introjective processes in the transference‐countertransference dynamics gradually revealed an unknown ancestral history. I clarify the back and forth process from dream to waking dream thoughts to moving metaphors and differentiate the moving metaphor from a living symbol. I argue that the containment of the analytic relationship nested within the security of the analytic space is a necessary precondition for such healing processes to occur.     

Parental Divorce,Parental Religious Characteristics,and Religious Outcomes in Adulthood

Parental divorce has been linked to religious outcomes in adulthood. Previous research, however, has not adequately accounted for parental religious characteristics, which may render the association spurious and/or moderate the relationship. Many studies also do not consider subsequent family context, namely, whether one's custodial parent remarries. Using pooled data from three waves of the General Social Survey, we examine the nature of the relationships among parental divorce, subsequent family structure, and religiosity in adulthood. Growing up in a single‐parent family—but not a stepparent family—is positively associated with religious disaffiliation and religious switching and negatively associated with regular religious service attendance. Accounting for parental religious characteristics, however, explains sizable proportions of these relationships. In fact, after accounting for parental religious affiliation and service attendance, growing up with a single parent does not have a significant effect on religious service attendance. Parental religiosity also moderates the relationship between growing up with a single parent and religious service attendance: being raised in a single‐parent home does have a negative effect on religious service attendance among adults who had two religiously involved parents. There is modest evidence of this moderating relationship for other religious outcomes. Implications of these findings are discussed.