Neurosteroids for a successful pregnancy

Steroid hormones play a critical role in the initiation and maintenance of pregnancy. In particular, the important role that the progesterone metabolite, and neurosteroid, allopregnanolone, may play in fetal and adolescent development is becoming increasingly evident. Unlike steroid hormones, neurosteroids act at nontraditional targets in the central and peripheral nervous systems, including GABA(A) receptor complexes. This commentary discusses the three works in this issue that elucidate the important role of allopregnanolone in the mechanisms that regulate stress hypo-sensitivity of rodents in late pregnancy, neuroprotective effects in fetal sheep exposed to a hypoxic insult, and the continuing role that prefrontal cortex formation of allopregnanolone may play on the cognitive development of gestationally stressed rat offspring, grown to adolescence. The narrative that these works comprise was facilitated by the 5(th) International Meeting on Steroids and the Nervous System (Torino, Italy), which is organized to update our knowledge on the relationships between steroid hormones synthesized in different organs and the nervous system. Topics covered in this most recent meeting included sex differences in, and hormonal influences on, cannabinoid-regulated biology; steroids and pain; the importance of co-regulatory factors for steroid receptor action in the brain; mechanism and role of estrogen-induced nonclassical signaling in the brain; vitamin D as the forgotten neurosteroid; neurosteroids and GABA(A) receptors; and pathogenic mechanisms mediated by glucocorticoid receptors in psychiatric disorders. The 6(th) International Meeting on Steroids and the Nervous System will be held in Torino, Italy in February 2011.     

催产素对产后抑郁症患者母性行为的调节作用

产后抑郁症是指女性分娩后一段时间内出现的严重抑郁发作现象。研究表明, 催产素不仅参与分娩过程和正常的母性行为表达, 也在调节产后抑郁的发病及患者的母性行为中起到了重要的作用。产后抑郁症患者的情绪和认知功能受损, 这可能导致了母性行为表达质量的下降; 催产素可以通过中脑边缘多巴胺系统来调控母性行为, 作用于内侧视前区(MPOA)来激活中脑腹侧被盖区(VTA)-伏隔核(NAc)环路从而影响伏隔核内多巴胺的分泌; 催产素对产后抑郁症中母性行为的调节机制可能是通过调节五羟色胺系统的功能来发挥抗焦虑作用, 也可能是通过与其它激素的交互作用来加速母性行为的表达。未来研究进一步明确催产素在中枢神经环路中的功能差异, 以及社会支持对产后抑郁症患者催产素的使用带来的影响。     

Radioligands for PET and SPECT Imaging of the central noradrenergic system

In the central nervous system, the neurotransmitter norepinephrine is involved in normal physiology, neuropsychiatric disorders, and the effects of numerous drugs. Although alterations of the central noradrenergic system are involved in the pathophysiology and pharmacotherapy of mood disorders, the basis and nature of these changes remain unresolved. Positron emission tomography (PET) and single photon emission computed tomography (SPECT) imaging agents will be valuable for further elucidating the roles of norepinephrine in health and disease. This review discusses PET and SPECT radioligands that have been developed for the enzymes, receptors, and transporters involved in noradrenergic neurotransmission. Currently, imaging agents that exhibit specific in vivo uptake in the brain have been described for monoamine oxidase A and beta-adrenergic receptors, but have not undergone detailed evaluation or experimental application. Based on the successful development and utilization of in vivo imaging agents for elements of the central dopaminergic and serotoninergic systems, PET and SPECT radioligands are expected to serve as new tools for studying the physiology, pathophysiology, and pharmacology of the central noradrenergic system.     

The effect of hormone replacement therapy on mood and everyday memory in younger mid-life women

Research on the effect of hormone replacement therapy (HRT) on both mood and memory indicates that oestrogen may enhance verbal memory in younger mid-aged women. This study examined the effect of HRT on everyday memory, while accounting for mood changes, in women between ages 40 and 60. A within-subjects comparison of 17 women, showed that mood, everyday memory, working memory, and delayed verbal memory improved after 3 months of HRT use. The improvement in memory was not mediated by mood, but changes in mood were moderated by exercise habits. The results suggest that verbal memory in particular may be enhanced by HRT in this age group, and everyday memory is an important construct to consider in future research.     

New lessons from knockout mice: The role of serotonin during development and its possible contribution to the origins of neuropsychiatric disorders

Serotonin (5-HT) modulates numerous processes in the central nervous system that are relevant to neuropsychiatric function and dysfunction. It exerts significant effects on anxiety, mood, impulsivity, sleep, ingestive behavior, reward systems, and psychosis. Serotonergic dysfunction has been implicated in several psychiatric conditions but efforts to more clearly understand the mechanisms of this influence have been hampered by the complexity of this system at the receptor level. There are at least 14 distinct receptors that mediate the effects of 5-HT as well as several enzymes that control its synthesis and metabolism. Pharmacologic agents that target specific receptors have provided clues regarding the function of these receptors in the human brain. 5-HT is also an important modulator of neural development and several groups have employed a genetic strategy relevant to behavior. Several inactivation mutations of specific 5-HT receptors have been generated producing interesting behavioral phenotypes related to anxiety, depression, drug abuse, psychosis, and cognition. In many cases, knockout mice have been used to confirm what has already been suspected based on pharmacologic studies. In other instances, mutations have demonstrated new functions of serotonergic genes in development and behavior.     

认知功能的性别差异

我们了概述认知功能的性别差异, 尤其是情节记忆功能的性别差异。已有的研究结果表明女性在言语生成、情节记忆、面孔识别任务中比男性存在明显的优势, 而男性的优势则表现在视空间任务中, 如视空间情节记忆任务。本文批判性地讨论了一个流行的假设: 类固醇激素影响认知功能的性别差异, 得出的结论是内源性睾丸激素或雌二醇均未显著影响认知功能的性别差异。     

A little bit louder now: negative affect increases perceived loudness

Traditionally, perception was considered to be an encapsulated process that was unaffected by top-down processes like affect. Recent work in vision draws this framework into question by showing that changes in the affective state of the perceiver can impact many different aspects of visual perception. Here, we extend the relationship between affect and perception into another perceptual modality: audition. Participants were induced into a negative or neutral mood by writing about a frightening or neutral experience in their past. They then listened to a series of short, neutral tones (320 and 640 ms) and rated the loudness and duration of the tones. Participants in a negative mood rated the tones as significantly louder, but not longer, than participants in a neutral mood, suggesting that the difference between the groups was perceptual rather than just a response bias. This research shows for the first time that the role of affect in perceptual processes may be more pervasive than previously considered.     

The cognitive regulation of emotions: The role of success versus failure experience and coping dispositions

Attention deployment and generating specific types of cognitions are central cognitive mechanisms of emotion regulation. Two groups of hypotheses make contradicting predictions about the emotion-cognition relationship. The moodcongruency hypothesis expects the emergence of mood-congruent cognitions (i.e., negative mood leads to negative and positive mood to positive cognitions). Similarly, a substantial body of research suggests that negative mood induces selffocus, whereas positive mood elicits an external focus of attention. The moodrepair hypothesis, on the other hand, assumes that persons in a negative mood state summon thoughts incongruent with that state and divert attention away from the self. However, the temporal sequence of cognitions assessed as well as coping dispositions, such as vigilance and cognitive avoidance, may moderate these relationships. Positive and negative emotional states were elicited by exposing the participants to the experience of success or failure in a demanding cognitive task. Cognitions that were present after emotion induction were assessed by means of a thought-listing procedure. For the total sample, results clearly confirmed the moodcongruency hypothesis. Thought order was a critical factor only for changes in self-focus. Thought valence (positive, neutral, negative) as well as self-focus were substantially influenced by coping dispositions.     

音乐训练对4~5岁幼儿普通话声调范畴感知能力的影响

已有研究表明, 音乐训练能提高成人对普通话声调范畴感知的能力, 此种训练能否增强幼儿对声调范畴感知的能力?训练效果是否受到训练时间长短的影响?本研究对幼儿园4~5岁幼儿进行音乐训练, 共40人, 分成音乐组和控制组, 每组各20人, 追踪考察音乐训练和训练时间长短对幼儿声调范畴感知能力提升的影响。实验采用前测-中测-后测设计, 对音乐组开展每周3次, 每次30分钟, 以小钟琴演奏为主的音乐训练; 控制组不进行任何有组织的训练活动。结果发现, 12个月音乐训练提升了幼儿对声调范畴感知的程度, 表现为音乐组幼儿范畴边界宽度显著小于控制组, 而训练6个月时, 该优势并不显著。此外, 12个月音乐训练还加强了幼儿区分范畴内刺激声学差异的敏感性, 而对范畴间刺激的区分能力无显著提高。本研究结果支持了音乐学习的歌剧理论(OPERA), 音乐训练具有跨域迁移作用, 可提升4~5岁幼儿对普通话声调范畴感知的能力, 但只有长期持续的训练才可能真正提高幼儿的音高精细化加工水平。     

On the primacy of the brain

It is well established that emotion is a product of complex interactions among the biological subsystems of the organism. The human nervous system must play a fundamental role in organizing and controlling the manifestation of these interactions. Since emotional disturbance is one of the major phenomena underlying maladaptive behavior, a solid understanding of its nature and mechanisms is essential for enhancing therapeutic practices. Although an increasing number of scholars now advocate the notion of the dependence of emotion on antecedent cognitive processes (e.g., Lazarus, 1982, 1984), and the relevance of both central and peripheral processes of the nervous system to emotional behavior (e.g., Panksepp, 1988; Pribram, 1984), Zajonc (1984) views emotion as independent of cognitive processes. This paper provides a critical evaluation of the basis of Zajonc’s (1984) argument from a neurobiological and psychotherapeutic point of view.     

On the primacy of the brain

It is well established that emotion is a product of complex interactions among the biological subsystems of the organism. The human nervous system must play a fundamental role in organizing and controlling the manifestation of these interactions. Since emotional disturbance is one of the major phenomena underlying maladaptive behavior, a solid understanding of its nature and mechanisms is essential for enhancing therapeutic practices. Although an increasing number of scholars now advocate the notion of the dependence of emotion on antecedent cognitive processes (e.g., Lazarus, 1982, 1984), and the relevance of both central and peripheral processes of the nervous system to emotional behavior (e.g., Panksepp, 1988; Pribram, 1984), Zajonc (1984) views emotion as independent of cognitive processes. This paper provides a critical evaluation of the basis of Zajonc’s (1984) argument from a neurobiological and psychotherapeutic point of view.     

Neurosteroids in the Hippocampus: Neuronal Plasticity and Memory

The hippocampus, which is critically involved in learning and memory processes, is known to be a target for the neuromodulatory actions of steroid hormones produced by the adrenal glands and gonads. Much of the work of B.S. McEwen and collaborators has focused on the role of glucocorticosteroids and estrogen in modulating hippocampal plasticity and functions. In addition to hormones derived from the endocrine glands, cells in the hippocampus may be exposed to locally synthesized neurosteroids, including pregnenolone, dehydroepiandrosterone and their sulfated esters as well as progesterone and its reduced metabolites. In contrast to hormones derived from the circulation, neurosteroids have paracrine and/or autocrine activities. In the hippocampus, they have been shown to have trophic effects on neurons and glial cells and to modulate the activity of a variety of neurotransmitter receptors and ion channels, including type A gamma-aminobutyric acid, N-methyl-D-aspartate and sigma receptors and N- and L-type Ca2+ channels. There is accumulating evidence that some neurosteroids, in particular pregnenolone sulfate, have strong influences on learning and memory processes, most likely by regulating neurotransmission in the hippocampus. However, the hippocampus is not the only target for the mnesic effects of neurosteroids. Associated brain regions, the basal nuclei of the forebrain and the amygdaloid complex, are also involved. Some neurosteroids may thus be beneficial for treating age- or disease-related cognitive impairments.     

Cognitive involvement in the mood response system

There is currently common agreement that moods are organized responses that affect many psychological subsystems, including the cognitive subsystem. The pleasant versus unpleasant quality of an individual's mood was the dependent measure in this study, which examined cognitive correlates of mood level. A set of tasks hypothesized to change with mood, an adjective scale measuring present mood state, and four personality scales were administered to 194 students. Results indicate that three tasks—giving advice to others, estimating the probability of events, and subjective ratings of associations to words—are correlated with mood state and mood-related traits (e.g., emotional distress). Because of the measurement of mood along a pleasant-unpleasant continuum, the present findings of cognitive change can be generalized to any mood that is mostly pleasant or unpleasant. Results also indicate that individuals low in neuroticism had greater correspondence between self-reported mood and performance on affect-sensitive tasks. The changes in cognition are discussed in the context of a spreading-activation view of mood effects and a depressive-schema theory of information processing. More generally, the results suggest that moods lead to broad influences on cognitive responses over considerable portions of an individual's life-span.Preparation of this article was supported in part by an Individual National Research Service Award, MH08978, from the National Institute of Mental Health to the first author. We gratefully acknowledge the assistance of Phoebe Ellsworth, Steven Tublin, Daniel Weinberger, and the reviewers for comments on earlier drafts of this article.     

Effects of September 11 on patients with obsessive compulsive disorder

Effects of the September 11, 2001 terrorist attacks in the USA were investigated in 25 patients with obsessive compulsive disorder and 27 normal controls 4-6 months after the attacks. Participants completed a 15-item questionnaire to retrospectively assess changes in mood, cognition, behavior and somatic complaints since September 11, 2001. Overall, both patients with obsessive compulsive disorder and normal controls reported minor changes in mood, behavior and somatic complaints. However, normal controls reported severe to extreme initial impact, slightly more cognitive symptoms (uncertainty about the future, intrusive recollections and greater desire to be with loved ones) and a slightly greater degree of overall impact on emotion and behavior at 1, 2 and 3 months after September 11 than did patients with obsessive compulsive disorder. Results support previous research that has found a relatively minor lasting impact of September 11 on both clinical and normal populations. Differences in cognition and coping mechanisms between normal controls and patients with obsessive compulsive disorder are proposed.     

Effects of September 11 on patients with obsessive compulsive disorder

Effects of the September 11, 2001 terrorist attacks in the USA were investigated in 25 patients with obsessive compulsive disorder and 27 normal controls 4–6 months after the attacks. Participants completed a 15‐item questionnaire to retrospectively assess changes in mood, cognition, behavior and somatic complaints since September 11, 2001. Overall, both patients with obsessive compulsive disorder and normal controls reported minor changes in mood, behavior and somatic complaints. However, normal controls reported severe to extreme initial impact, slightly more cognitive symptoms (uncertainty about the future, intrusive recollections and greater desire to be with loved ones) and a slightly greater degree of overall impact on emotion and behavior at 1, 2 and 3 months after September 11 than did patients with obsessive compulsive disorder. Results support previous research that has found a relatively minor lasting impact of September 11 on both clinical and normal populations. Differences in cognition and coping mechanisms between normal controls and patients with obsessive compulsive disorder are proposed.     

The cerebellum in thought and action: a fronto-cerebellar aging hypothesis

Normal aging is associated with deficits in both memory and executive control. While a number of theories of cognitive aging have proposed that decrements in frontally mediated executive control processes can account for many of the age-related changes observed, the models proposed to date have not adequately accounted for age changes in processing speed, intra-individual variability and automaticity of information processing. These basic aspects of information processing efficiency may be of central importance for our understanding of age-related cognitive changes and more elaborate neurological models are needed that incorporate explanatory mechanisms which account for their influence. In this paper, it is proposed that the dual role played by frontal and cerebellar degeneration and the disruption of fronto-cerebellar feedback and feedforward control loops may be of central importance for a model of age-related changes in processing speed, intra-individual variability, automaticity, and higher level cognitive functions like memory and executive control.     

Cognitive neuroscience from a behavioral perspective: A critique of chasing ghosts with geiger counters

Cognitive neuroscience is a growing new discipline concerned with relating complex behavior to neuroanatomy. Relatively new advances in the imaging of brain function, such as positron emission tomography (PET), have generated hundreds of studies that have demonstrated a number of interesting but also potentially problematic brain-behavior relations. For example, cognitive neuroscientists largely favor interpretations of their data that rely on unobserved hypothetical mechanisms. Their reports often contain phraseology such as central executive, willed action, and mental imagery. As B. F. Skinner argued for decades, cognitive constructs of neurological data may yield nothing more than a conceptual nervous system.     

情绪生理机制研究的外周与中枢神经系统整合模型

阐明人类情绪的生理机制是心理学家和神经科学家所面临的巨大挑战。以往研究倾向于分别考察情绪的外周反应模式和脑机制。近年来,随着情绪电生理学和认知神经科学的发展,许多研究者从外周与中枢神经系统相互作用的角度,提出了一些解释情绪生理机制的整合模型。其中,以情绪环路模型和神经内脏整合模型为典型代表。前者强调由外周到中枢的自下而上的加工方式,试图说明情绪经验形成的机制;后者则采取由中枢到外周的自上而下的加工方式,试图阐明情绪调控的机制。今后的研究有必要借鉴这两个模型,并结合近期有关情绪信息加工神经机制的新成果,以便构建能够更为全面解释人类情绪的生理模型。     

Differential cognitive response to a mood challenge following successful cognitive therapy or pharmacotherapy for unipolar depression

This study examined the nature of cognitive reactivity to mood changes in formerly depressed patients. Patients who recovered either through cognitive-behavior therapy (CBT; N = 25) or through pharmacotherapy (PT; N = 29) completed self-reported ratings of dysfunctional attitudes before and after a negative mood induction procedure. In response to similar levels of induced sad mood, PT patients showed a significant increase in dysfunctional cognitions compared with patients in the CBT group. To evaluate the effects of such cognitive reactivity on the subsequent course of depression, follow-up analyses reassessed 30 patients several years after initial testing. Results indicated that patients' reactions to the mood induction procedure were predictive of depressive relapse. These findings argue for differential effects of treatment on cognitive reactivity to mood induction and for the link between such reactivity and risk for later depressive relapse.