进化心理学对心理素质结构研究的整合与重构——以学生心理素质结构研究为例

传统的心理素质结构研究模式不经济,研究结果出现纵向断裂横向分裂的趋势.从进化心理学的视角来看,心理素质结构的最终功能均指向个体的适应性,其形成是与周围环境不断排斥和融合的过程.建构的心理素质结构融合模型能在一定程度上解决传统研究模式的弊端,并建议今后的研究应以分析人为主导转而分析人及其所处的文化环境并重,进而引导人的心理素质结构的不断发展.     

个体对效价预期和风险评估的时程加工机制:来自ERP的证据

采用事件相关电位技术(ERP),通过简单赌博任务,操纵结果预期的效价(输或赢)与风险(高风险与低风险),考察了个体对结果预期阶段的效价和风险评估的脑内时程动态加工过程。脑电结果发现:(1)在N2成分上,结果预期的效价主效应显著,预期输比预期赢能够引起更大的N2波幅;结果预期的风险主效应不显著。(2)在N500成分上,效价与风险之间的交互作用边缘显著,进一步简单效应分析发现,在预期输的条件下,肯定会输的N500波幅显著大于可能会输;而在预期赢的条件下,肯定会赢与可能会赢之间的N500波幅差异不显著。这说明,在不确定决策过程中的结果预期阶段,个体可能先对结果预期的效价进行加工,然后再对风险进行评估。     

Influence of brain-derived neurotrophic factor and catechol O-methyl transferase polymorphisms on effects of meditation on plasma catecholamines and stress

Meditation may show differential effects on stress and plasma catecholamines based on genetic polymorphisms in brain-derived neurotrophic factor (BDNF) and catechol O-methyl transferase (COMT). Eighty adults (40 men, 40 women; mean age 26 years) who practiced meditation regularly and 57 healthy control adults (35 men, 22 women; mean age 26 years) participated. Plasma catecholamines (norepinephrine (NE), epinephrine (E), and dopamine (DA)) concentrations were measured, and a modified form of the Stress Response Inventory was administered. The results were analyzed using two-way analysis of covariance (ANCOVA) with control and meditation subjects, gene polymorphism as factors, and meditation duration as the covariate. Two-way ANCOVA showed a significant interaction between control and meditation subjects, and BDNF Val66Met polymorphism on DA/NE+DA/E (p = 0.042) and NE/E+NE/DA (p = 0.046) ratios. A significant interaction was found for control and meditation subjects with COMT Val158Met polymorphism and plasma NE concentrations (p = 0.009). Post hoc ANCOVA in the meditation group, adjusted for meditation duration, showed significantly higher plasma NE concentrations for COMT Met carriers than COMT Val/Val subjects (p = 0.025). Significant differences of stress levels were found between the control and meditation subjects in BDNF Val/Met (p < 0.001) and BDNF Met/Met (p = 0.003), whereas stress levels in the BDNF Val/Val genotype did not differ between the control and meditation groups. This is the first evidence that meditation produces different effects on plasma catecholamines according to BDNF or COMT polymorphisms.     

Eye movements of second language learners when reading spaced and unspaced Chinese text

The effect of spacing in relation to word segmentation was examined for four groups of non-native Chinese speakers (American, Korean, Japanese, and Thai) who were learning Chinese as second language. Chinese sentences with four types of spacing information were used: unspaced text, word-spaced text, character-spaced text, and nonword-spaced text. Also, participants' native languages were different in terms of their basic characteristics: English and Korean are spaced, whereas the other two are unspaced; Japanese is character based whereas the other three are alphabetic. Thus, we assessed whether any spacing effects were modulated by native language characteristics. Eye movement measures showed least disruption to reading for word-spaced text and longer reading times for unspaced than character-spaced text, with nonword-spaced text yielding the most disruption. These effects were uninfluenced by native language (though reading times differed between groups as a result of Chinese reading experience). Demarcation of word boundaries through spacing reduces non-native readers' uncertainty about the characters that constitute a word, thereby speeding lexical identification, and in turn, reading. More generally, the results indicate that words have psychological reality for those who are learning to read Chinese as a second language, and that segmentation of text into words is more beneficial to successful comprehension than is separating individual Chinese characters with spaces.     

fMRI correlates of inhibition of return in perifoveal and peripheral visual field

When a target appears in the same peripheral location as a previous cue, responding is typically delayed if the cue-target interval is relatively long. This phenomenon is termed inhibition of return (IOR) and has been suggested to reflect an attentional bias in favour of novel visual space. It has been demonstrated recently that IOR is much stronger in the far periphery than in the perifoveal visual field. The present study further investigated the neural mechanisms underlying this eccentricity effect of IOR with an event-related fMRI technique. The results demonstrated a stronger activation in visual cortex for perifoveal processing and a broader activation in multiple brain areas for peripheral processing. When IOR effects were compared between these two areas, a stronger activation of the fronto-parietal network was evidenced for perifoveal versus peripheral IOR, while the prefrontal cortex was more strongly involved in the peripheral IOR versus perifoveal IOR. These results suggest that different neural mechanisms are mediating the dissociable inhibitory functions between the perifoveal and peripheral visual field.     

Non-target language processing in Chinese-English bilinguals: a study of event-related potential

The event-related brain potential (ERP) technique was used to investigate the neural mechanism of non-target language processing in Chinese-English bilinguals. Participants were presented with a mixed list of Chinese and English words and required to make conceptual decisions for words in one language and ignore words in the other non-target language. Regardless of whether the nontarget word was in Chinese or English, the ERPs they elicited were modulated by word frequency, suggesting that their meaning had been accessed. The N400 peak was delayed in the English as the non-target language condition, probably because participants were less proficient in English. The results suggest that the non-target language can be processed during conceptual tasks with participants' proficiency in this language being a critical factor.     

Implicit Science Stereotypes Mediate the Relationship between Gender and Academic Participation

While the gender gap in mathematics and science has narrowed, men pursue these fields at a higher rate than women. In this study, 165 men and women at a university in the northeastern United States completed implicit and explicit measures of science stereotypes (association between male and science, relative to female and humanities), and gender identity (association between the concept “self” and one’s own gender, relative to the concept “other” and the other gender), and reported plans to pursue science-oriented and humanities-oriented academic programs and careers. Although men were more likely than women to plan to pursue science, this gap in students’ intentions was completely accounted for by implicit stereotypes. Moreover, implicit gender identity moderated the relationship between women’s stereotypes and their academic plans, such that implicit stereotypes only predicted plans for women who strongly implicitly identified as female. These findings illustrate how an understanding of implicit cognitions can illuminate between-group disparities as well as within-group variability in science pursuit.     

The reciprocal relations between teachers' perceptions of children's behavior problems and teacher-child relationships in the first preschool year

To examine the reciprocal relations between teacher-child relationships and children's behavior problems, the authors analyzed cross-lagged longitudinal data on teacher-child relationships and children's internalizing and externalizing problems using a structural equation modeling approach. The homeroom teachers of 105 first-year preschoolers aged 2-3 years filled in the Student-Teacher Relationship Scale and the Child Behavior Checklist/2-3, first at 3 months after the children's preschool entrance and then at the end of the first preschool year. Results showed significant cross-wave reciprocal relations between externalizing problems and teacher-child conflict and significant cross-wave relation from early internalizing problems to later teacher-child conflict. However, the cross-wave associations between internalizing and externalizing problems and teacher-child closeness were not significant.     

Mechanism of isoflavone aglycone's effect on cognitive performance of senescence-accelerated mice

This study investigated the effect of isoflavone aglycone (IA) on the learning and memory performance of senescence-accelerated mice, and explored its neural protective mechanism. Results showed that SAM-P/8 senescence-accelerated mice treated with IA performed significantly better in the Y-maze cognitive test than the no treatment control (P<0.05). The cortex AchE activity, serum SOD and GSH-Px activities were notably higher (P<0.05). MDA concentration and the β-secretase activity in the hippocampal tissue were both lower (P<0.05). Additionally, the number of hippocampal neurons was increased and cell morphology was significantly improved. Data suggested that IA could indirectly increase concentration of the cholinergic neural transmitter Ach through regulation of AchE, therefore improving the central cholinergic function and enhancing the learning and memory ability. By reducing the β-secretase activity, IA could decrease the formation and deposition of insoluble Adebris, relieve the resulted toxicity and damage to neurons, and thereby effectively protect the nervous system.     

The effect of food toppings on calorie estimation and consumption

In this research we examine the effect of adding a food topping to the base food on consumers' calorie estimation and consumption of the augmented food (base food plus topping). We show that consumers underestimate the calorie content of augmented food with an unhealthy base, especially when the topping is healthy. However, consumers are less likely to underestimate the calorie content of augmented food with a healthy base, regardless of whether the topping is healthy or unhealthy. Further, we show that adding a healthy topping to an unhealthy base makes consumers not only underestimate the calorie content but also eat more of the augmented food.