Cognitive control of a simple mental image in patients with obsessive--compulsive disorder

The nature of obsessions has led researchers to try to determine if the main problem in obsessive-compulsive disorder (OCD) is impaired inhibitory control. Previous studies report that the effort to suppress is one of the factors that increase the frequency of obsessive thoughts. Based on these results and those of the present study that suggest inferior parietal lobe (IPL) abnormality in OCD and findings of a recent study that reported the importance of the right posterior parietal cortex in cognitive control of a simple mental image, the present cognitive control paradigm study aimed to determine whether there is a difference in brain dynamics between OCD patients and non-obsessive controls while performing tasks that necessitate cognitive control of a simple mental image, and whether the right posterior parietal region is one of the regions in which a difference in activity between the OCD patients and controls would be observed. Functional brain imaging was performed while the participants attempted to suppress, imagine, or manipulate a mental image. The general linear model showed that there was a main effect of group and main effect of task. Accordingly, in all contrasts (suppression minus free-imagination, erasing minus free-imagination, and imagination minus free-imagination), the right IPL, right posterior cingulate cortex, and right superior frontal gyrus activity were lower in the OCD patients than in the healthy controls. These results and the observed correlations between activity levels, and symptom and subjective performance scores are discussed. In conclusion, the results of the present study and those of previous studies suggest that the main problem in OCD might be difficulty activating the right frontoparietal networks during tasks that require cognitive control, which might result in the intrusiveness of obsessive thoughts.     

Functional brain activation differences in stuttering identified with a rapid fMRI sequence

The purpose of this study was to investigate whether brain activity related to the presence of stuttering can be identified with rapid functional MRI (fMRI) sequences that involved overt and covert speech processing tasks. The long-term goal is to develop sensitive fMRI approaches with developmentally appropriate tasks to identify deviant speech motor and auditory brain activity in children who stutter closer to the age at which recovery from stuttering is documented. Rapid sequences may be preferred for individuals or populations who do not tolerate long scanning sessions. In this report, we document the application of a picture naming and phoneme monitoring task in 3 min fMRI sequences with adults who stutter (AWS). If relevant brain differences are found in AWS with these approaches that conform to previous reports, then these approaches can be extended to younger populations. Pairwise contrasts of brain BOLD activity between AWS and normally fluent adults indicated the AWS showed higher BOLD activity in the right inferior frontal gyrus (IFG), right temporal lobe and sensorimotor cortices during picture naming and higher activity in the right IFG during phoneme monitoring. The right lateralized pattern of BOLD activity together with higher activity in sensorimotor cortices is consistent with previous reports, which indicates rapid fMRI sequences can be considered for investigating stuttering in younger participants.Educational objectives: The reader will learn about and be able to describe the: (1) use of functional MRI to study persistent developmental stuttering; (2) differences in brain activation between persons who stutter and normally fluent speakers; and (3) potential benefit of time efficient fMRI sequences combined with a range of speech processing tasks for investigating stuttering in younger populations.     

Parent-Child Engagement in Decision Making and the Development of Adolescent Affective Decision Capacity and Binge Drinking

The goal of this study was to investigate how parents’ engagement of their child in everyday decision-making influenced their adolescent’s development on two neuropsychological functions, namely, affective decision-making and working memory, and its effect on adolescent binge-drinking behavior.We conducted a longitudinal study of 192 Chinese adolescents. In 10th grade, the adolescents were tested for their affective decision-making ability using the Iowa Gambling Task (IGT) and working memory capacity using the Self-ordered Pointing Test (SOPT). Questionnaires were used to assess perceived parent-child engagement in decision-making, academic performance and drinking behavior. At one-year follow-up, the same neuropsychological tasks and questionnaires were repeated.Results indicate that working memory and academic performance were uninfluenced by parent-child engagement in decision-making. However, compared to adolescents whose parents made solitary decisions for them, adolescents engaged in everyday decision-making showed significant improvement on affective decision capacity and significantly less binge-drinking one year later.These findings suggest that parental engagement of children in everyday decision-making might foster the development of neurocognitive functioning relative to affective decision-making and reduce adolescent substance use behaviors.     

The Role of Emotion in Decision Making: A Cognitive Neuroscience Perspective

ABSTRACT— Decision making often occurs in the face of uncertainty about whether one's choices will lead to benefit or harm. The somatic-marker hypothesis is a neurobiological theory of how decisions are made in the face of uncertain outcome. This theory holds that such decisions are aided by emotions, in the form of bodily states, that are elicited during the deliberation of future consequences and that mark different options for behavior as being advantageous or disadvantageous. This process involves an interplay between neural systems that elicit emotional/bodily states and neural systems that map these emotional/bodily states.     

右腹外侧前额叶对高抑郁水平成年人社会情绪调节的作用：一项tDCS研究

已有的经颅直流电刺激(transcranial direct current stimulation, tDCS)研究证明, 右腹外侧前额叶(right ventrolateral prefrontal cortex, RVLPFC)是社会情绪调节的重要脑区, 激活RVLPFC可显著降低人们对社会性负性情绪体验的强度。社会功能受损是抑郁症患者或抑郁倾向人群的重要特征之一。该群体对社会排斥的敏感性高, 且对负性社会情绪体验的情绪调节能力降低。在本研究中, 我们采用外显的情绪调节任务, 研究了高、低抑郁水平的两组成年人被试在RVLPFC接受阳性tDCS后其情绪调节能力的改变。结果表明, 虽然采用tDCS激活RVLPFC可帮助被试通过情绪调节(认知重评)减弱负性情绪体验, 但高抑郁水平被试的负性情绪强度下降程度明显小于低抑郁水平被试。另外本文还发现, 与源于个人的负性情绪相比, tDCS效应对源于社会的负性情绪(即社会排斥)更强。本研究是采用电或磁刺激提高抑郁人群社会情绪调节能力的首次尝试。实验结果表明, 高抑郁水平成年人的RVLPFC仅通过单次、短时间(34 min)的tDCS激活, 其情绪调节能力并未得到显著提升。这提示对抑郁倾向群体或抑郁症患者的干预或治疗需要多次施加tDCS。     

Developmental grey matter changes in superior parietal cortex accompany improved transitive reasoning

The neural basis of developmental changes in transitive reasoning in parietal regions was examined, using voxel-based morphometry. Young adolescents and adults performed a transitive reasoning task, subsequent to undergoing anatomical magnetic resonance imaging (MRI) brain scans. Behaviorally, adults reasoned more accurately than did the young adolescents. Neural results showed (i) less grey matter density in superior parietal cortex in the adults than in the young adolescents, possibly due to a developmental period of synaptic pruning; (ii) improved performance in the reasoning task was negatively correlated with grey matter density in superior parietal cortex in the adolescents, but not in the adult group; and (iii) the latter results were driven by the more difficult trials, requiring greater spatial manipulation. Taken together, the results support the idea that during development, regions in superior parietal cortex are fine-tuned, to support more robust spatial manipulation, resulting in greater accuracy and efficiency in transitive reasoning.     

The Motivational Origins of Religious Practices

I hypothesize that people engage in religious practices, in part, because such practices activate the frontal lobes. Activation of the frontal lobes is both intrinsically rewarding and necessary for acquisition of many of the behaviors that religions seek to foster, including self-responsibility, impulse and emotion modulation, empathy, moral insight, hope, and optimism. Although direct tests of the hypothesis are as yet nonexistent, there is reasonably strong circumstantial evidence (reviewed herein) for it. Recent brain-imaging studies indicate greater anterior activation values and increased blood flow to frontal sites during prayer and meditation. Regular prayer is positively correlated with better overall mental health. Religiosity is correlated with higher levels of self-monitoring, empathy, and moral insight and other positive behaviors and negatively correlated with depression and impulsive and risky behaviors. Independent data show that self-monitoring, empathy, hope, and moral insight are all selectively associated with intact frontal function, whereas depression, impulsiveness, and drug and alcohol abuse are associated selectively with frontal dysfunction. If religious practices do indeed preferentially activate and stimulate development of the frontal lobes, (a) religious practices should be considered as possible adjuncts for some patients in treatment for mental health disorders, and (b) the frontal lobes (rather than the temporal lobes) should be considered the major brain site that supports the core components of religious experience.     

选择注意神经机制:前扣带皮层对躯体感觉输入的丘脑-皮层调制

本文阐述了认知神经科学关于选择注意发生在感知觉中枢信息流加工较早阶段以及前扣带皮层（ACC）在丘脑和初级感觉皮层水平调制躯体感觉输入的研究证据,揭示了ACC在感知觉信息加工早期的选择注意控制执行机能,以及实行该机能的神经途径。     

An analysis of independence and interactions of brain substrates that subserve multiple attributes, memory systems, and underlying processes

It is proposed that memory is organized into event-based, knowledge-based, and rule-based memory systems. Furthermore, each system is composed of the same set of multiple attributes and characterized by a set of process oriented operating characteristics that are mapped onto multiple neural regions and interconnected neural circuits. Based on this theoretical model of memory, it is possible to investigate the independence and interaction among brain regions between any two systems for any of the proposed attributes or processes. This applies also to the investigation of independence and interactions between any two attributes within a system and between processes associated with a system for any of the proposed attributes. In this article, research evidence is presented to suggest that there are both dissociations and interactions between the hippocampus and caudate nucleus in mediating spatial and response attributes within the event-based memory system, between the hippocampus and the parietal cortex in subserving the spatial attribute within the event-based and knowledge-based memory systems, and between the hippocampus and the prefrontal cortex in subserving the spatial attribute within the event-based and rule-based memory systems.