催产素对决策行为的影响及其神经基础

发布时间：2018-01-24 17:34

本文关键词： 催产素爱荷华赌博测验神经基础　出处：《西南大学》2017年硕士论文　论文类型：学位论文

【摘要】：催产素是一种环状九肽分子。一方面,它可以作为一种激素作用于外周神经系统,调节子宫收缩、刺激乳汁排出、促进分娩等。另一方面,它还可以作为一种神经递质作用于中枢神经系统,调节人类多种社会性行为。决策是指对不同方案的利弊得失进行权衡,对其主观预期价值进行评估,并最终做出选择的过程。目前心理学领域关于催产素和决策的研究有很多,但这些研究主要集中在信任博弈、最后通牒任务、囚徒困境等社会互动相关的决策行为上,而对于不涉及人际互动的决策行为目前研究相对较少。本研究在前人研究的基础上试图将催产素和不涉及人际互动的决策行为结合起来,通过三个研究来探讨催产素对人们决策行为的影响及其背后的神经基础。研究一通过行为层面的研究,考察鼻喷催产素组的被试与安慰剂组的被试在爱荷华赌博测验任务上行为表现的差异。研究二采用假连续式动脉自旋标记成像技术对安慰剂组被试进行核磁扫描,同时记录ASL和BOLD两种信号。通过分析同一扫描序列中两种信号下被试爱荷华赌博测验激活脑区的异同,探讨使用ASL来进行爱荷华赌博测试的f MRI实验是否具有可行性。研究三同样通过脑成像的研究,考察催产素和安慰剂两种不同条件下,被试在爱荷华赌博测验上大脑激活的差异。研究一招募了34名西南大学健康男性志愿者,首先让他们向鼻腔内喷入催产素或安慰剂(此过程采用双盲设计,催产素组16名,安慰剂组18名)。随后施测瑞文标准推理测验,时长40分钟。最后,让参与者完成爱荷华赌博测验任务,时长15分钟。结果显示,催产素组被试成绩显著优于安慰剂组。基于期望效价模型的分析发现,催产素组选择一致性水平(c)显著大于安慰剂组。研究二将研究一中喷射过安慰剂,完成瑞文标准推理测验的18名被试作为研究对象,对他们进行核磁扫描。首先扫描静息态,然后扫描结构像,最后让被试在核磁共振扫描仪中进行爱荷华赌博测验,对这一决策过程进行扫描。通过对同一扫描序列中两种不同信号下(BOLD和ASL)被试爱荷华赌博测验激活脑区的异同进行分析,结果显示,ASL和BOLD在决策阶段脑区激活相似,存在许多共同激活脑区。将这些共同激活脑区做成mask,分别提取每个mask里所有体素的平均激活强度值,将提取出来的数据与行为数据做相关分析。结果表明,左侧枕叶皮层和左侧顶叶皮层两个脑区的激活与实验第五阶段爱荷华赌博测验分数之间存在显著正相关。左侧壳核脑区激活与实验第五阶段和整个实验全程爱荷华赌博测验的分数均存在显著负相关。进一步分析发现,ASL的激活强度相对较低,BOLD激活强度较强。因此,在爱荷华赌博测验的核磁研究中,采用BOLD信号来进行扫描更加合适。基于研究二的实验结果,研究三采用BOLD效应f MRI进行扫描。研究选取研究一中喷射过催产素,完成瑞文标准推理测验的16名被试作为研究对象,对他们进行核磁扫描,扫描过程同研究二。结果显示,在反馈早期阶段,催产素组中央后回、前额叶、扣带回、顶上小叶脑区的激活显著大于安慰剂组;在整个决策阶段,催产素组被试中央前回和中央后回的激活显著大于安慰剂组;在整个反馈阶段,催产素组额叶、顶上小叶、中央后回、旁扣带回的激活显著大于安慰剂组。在决策早期、决策晚期、反馈晚期三个阶段,没有发现显著脑区激活差异。进一步将未校正的结果提取出来分析,统计结果采用基于高斯随机场的团块校正法,团块生成的阈限值为Z2.0,团块校正的p值设置为0.05,FWE校正。校正后发现四个脑区激活:右侧舌回、左侧前额叶、右侧前额叶、右侧中央前后回。将这些激活脑区做成mask,分别提取每个mask里所有体素的平均激活强度值,将提取出来的数据与行为数据做相关分析。结果表明,前额叶脑区和右侧中央前后回激活与催产素组被试选择CD纸牌的比例存在显著正相关,与AB两组纸牌的选择比例存在显著负相关。而与安慰剂组被试的选择不存在明显相关关系。由此可以推断,催产素组被试爱荷华赌博测验成绩优于安慰剂组,可能的机制是催产素增强了被试前额叶脑区的激活。综合上述三个研究结果,得出结论:鼻喷催产素会增强个体前额叶脑区的激活,使得个体在爱荷华赌博测验上决策能力提高。
[Abstract]:Oxytocin is a ring of nine peptide molecules. On the one hand, it can be used as a hormone in the peripheral nervous system, regulate uterine contraction, stimulate milk discharge, promote childbirth. On the other hand, it can also serve as a neurotransmitter in the central nervous system, regulating human various social behavior. Decision making refers to the advantages and disadvantages of different schemes are weighed to evaluate the subjective expected value, and make the final choice. At present, the field of psychology on oxytocin and decision research are many, but these studies mainly concentrated in the trust game, ultimatum game, prisoner's Dilemma and other social interaction related decision behavior. The decision behavior does not involve interpersonal interaction at present relatively little research. This study on the basis of previous studies to oxytocin and does not involve the interpersonal decision-making behavior together, through Three a study to explore the effect of oxytocin on people decision-making behavior and its underlying neural basis. A study by the behavioral research, investigation of nasal spray oxytocin group was tested with placebo differences between subjects behavior in the Iowa gambling task. Two test research using false continuous arterial spin labeling imaging in the placebo group were tested by MRI scans, while recording the ASL and BOLD two kinds of signals. Through the analysis of two kinds of similarities and differences in the same scan sequence signal under the Iowa gambling test brain activation, to investigate whether the f MRI experiment using ASL to test the feasibility of gambling in Iowa. On three through the same brain the imaging study, oxytocin and placebo in two different conditions, the subjects of brain activation in the Iowa gambling test. A study recruited 34 healthy male volunteers in Southwestern University First of all, let them into the nasal cavity injection of oxytocin or placebo (this process by double blind design, oxytocin group 16, 18 in the placebo group). Then measure Raven's standard progressive matrices, 40 minutes long. Finally, let the participants completed the Iowa gambling task, 15 minutes long. The results showed the oxytocin group, test results are significantly better than placebo group. Analysis of expectency model based on the discovery, the oxytocin group selection consistency level (c) was significantly higher than the placebo group. Two will study a placebo injection, complete the Raven standard reasoning test 18 subjects as the research object, magnetic scanning on them the first scan. Resting state, then scan like structure, finally let the participants of the Iowa gambling test in an MRI scanner, scan of a decision process. Based on the two different signal sequences under the same scanning (BOLD and A SL) is the Iowa gambling test brain activation differences were analyzed, results showed that ASL and BOLD in the decision-making stage of brain activation is similar, there are many common brain activation. These common brain activation made mask, mask extracted from each voxel mean activation intensity values, data and behavior data the extracted correlation analysis. The results showed that there was a positive correlation between the left occipital cortex and left parietal cortex in two brain regions and experiment of the fifth stage of the Iowa gambling test scores. The activation of the left putamen brain regions and the fifth phase of the experiment and the whole experiment of Iowa gambling test scores were negatively related to further. Analysis found that the activation intensity of ASL is relatively low, the activation of BOLD strong strength. Therefore, in the study of gambling in Iowa nuclear test, more suitable for scanning using BOLD signals. Research results based on the two of three by BOLD effect of F MRI for scanning. A study in the injection of oxytocin, complete the Raven standard reasoning test 16 subjects as the research object, for an MRI scan on them, with two of the scanning process. The results showed that in the early stage of feedback, the oxytocin group Mae Uaba, postcentral gyrus, cingulate gyrus, superior parietal lobule activation of brain regions were significantly higher than those in the placebo group; in the decision-making stage, the oxytocin group subjects precentral activation was significantly greater than the placebo group; in the feedback stage, the oxytocin group frontal, parietal lobule, postcentral gyrus. Beside the cingulate activation was significantly greater than the placebo group. In early decision, decision feedback late, late three stages, found no significant difference activation of brain regions. The uncorrected results from statistical analysis, results based on Gauss With the mass correction of the airport, the threshold value of Z2.0 mass production, mass correction P correction FWE is set to 0.05. After the correction and found that activation of four brain regions: the right lingual gyrus, left prefrontal lobe, right prefrontal cortex, right before and after the central back. The activated brain region is made respectively from each mask mask all the average intensity of activation in value, data and behavior data will be extracted by correlation analysis. The results show that before and after the prefrontal brain regions and right back to the central activation and oxytocin were significantly positively related CD cards proportional selection, has significant negative correlation with the proportion of group AB two cards. There are obvious correlation with the placebo subjects. It can be inferred that the oxytocin group was the Iowa gambling test scores better than the placebo group, the possible mechanism of oxytocin enhanced subjects prefrontal brain regions activated. The above three findings conclude that nasal spray oxytocin can enhance the activation of prefrontal cortex and improve the decision-making ability of individuals in Iowa gambling test.

【学位授予单位】：西南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：B845.1

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