Empathy for pain involves the affective but not sensory components of pain.

Our ability to have an experience of another's pain is characteristic of empathy. Using functional imaging, we assessed brain activity while volunteers experienced a painful stimulus and compared it to that elicited when they observed a signal indicating that their loved one--present in the same room--was receiving a similar pain stimulus. Bilateral anterior insula (AI), rostral anterior cingulate cortex (ACC), brainstem, and cerebellum were activated when subjects received pain and also by a signal that a loved one experienced pain. AI and ACC activation correlated with individual empathy scores. Activity in the posterior insula/secondary somatosensory cortex, the sensorimotor cortex (SI/MI), and the caudal ACC was specific to receiving pain. Thus, a neural response in AI and rostral ACC, activated in common for "self" and "other" conditions, suggests that the neural substrate for empathic experience does not involve the entire "pain matrix." We conclude that only that part of the pain network associated with its affective qualities, but not its sensory qualities, mediates empathy.

Dopamine and performance in a reinforcement learning task: Evidence from Parkinson's disease

The role dopamine plays in decision-making has important theoretical, empirical and clinical implications. Here, we examined its precise contribution by exploiting the lesion deficit model afforded by Parkinson's disease. We studied patients in a two-stage reinforcement learning task, while they were ON and OFF dopamine replacement medication. Contrary to expectation, we found that dopaminergic drug state (ON or OFF) did not impact learning. Instead, the critical factor was drug state during the performance phase, with patients ON medication choosing correctly significantly more frequently than those OFF medication. This effect was independent of drug state during initial learning and appears to reflect a facilitation of generalization for learnt information. This inference is bolstered by our observation that neural activity in nucleus accumbens and ventromedial prefrontal cortex, measured during simultaneously acquired functional magnetic resonance imaging, represented learnt stimulus values during performance. This effect was expressed solely during the ON state with activity in these regions correlating with better performance. Our data indicate that dopamine modulation of nucleus accumbens and ventromedial prefrontal cortex exerts a specific effect on choice behaviour distinct from pure learning. The findings are in keeping with the substantial other evidence that certain aspects of learning are unaffected by dopamine lesions or depletion, and that dopamine plays a key role in performance that may be distinct from its role in learning. © 2012 The Author.

Changing the responses of cortical neurons from sub- to suprathreshold using single spikes in vivo.

Action Potential (APs) patterns of sensory cortex neurons encode a variety of stimulus features, but how can a neuron change the feature to which it responds? Here, we show that in vivo a spike-timing-dependent plasticity (STDP) protocol-consisting of pairing a postsynaptic AP with visually driven presynaptic inputs-modifies a neurons' AP-response in a bidirectional way that depends on the relative AP-timing during pairing. Whereas postsynaptic APs repeatedly following presynaptic activation can convert subthreshold into suprathreshold responses, APs repeatedly preceding presynaptic activation reduce AP responses to visual stimulation. These changes were paralleled by restructuring of the neurons response to surround stimulus locations and membrane-potential time-course. Computational simulations could reproduce the observed subthreshold voltage changes only when presynaptic temporal jitter was included. Together this shows that STDP rules can modify output patterns of sensory neurons and the timing of single-APs plays a crucial role in sensory coding and plasticity.DOI:http://dx.doi.org/10.7554/eLife.00012.001.

Functional requirements for reward-modulated spike-timing-dependent plasticity.

Recent experiments have shown that spike-timing-dependent plasticity is influenced by neuromodulation. We derive theoretical conditions for successful learning of reward-related behavior for a large class of learning rules where Hebbian synaptic plasticity is conditioned on a global modulatory factor signaling reward. We show that all learning rules in this class can be separated into a term that captures the covariance of neuronal firing and reward and a second term that presents the influence of unsupervised learning. The unsupervised term, which is, in general, detrimental for reward-based learning, can be suppressed if the neuromodulatory signal encodes the difference between the reward and the expected reward-but only if the expected reward is calculated for each task and stimulus separately. If several tasks are to be learned simultaneously, the nervous system needs an internal critic that is able to predict the expected reward for arbitrary stimuli. We show that, with a critic, reward-modulated spike-timing-dependent plasticity is capable of learning motor trajectories with a temporal resolution of tens of milliseconds. The relation to temporal difference learning, the relevance of block-based learning paradigms, and the limitations of learning with a critic are discussed.

Cognitive Tomography Reveals Complex, Task-Independent Mental Representations

Humans develop rich mental representations that guide their behavior in a variety of everyday tasks. However, it is unknown whether these representations, often formalized as priors in Bayesian inference, are specific for each task or subserve multiple tasks. Current approaches cannot distinguish between these two possibilities because they cannot extract comparable representations across different tasks [1-10]. Here, we develop a novel method, termed cognitive tomography, that can extract complex, multidimensional priors across tasks. We apply this method to human judgments in two qualitatively different tasks, "familiarity" and "odd one out," involving an ecologically relevant set of stimuli, human faces. We show that priors over faces are structurally complex and vary dramatically across subjects, but are invariant across the tasks within each subject. The priors we extract from each task allow us to predict with high precision the behavior of subjects for novel stimuli both in the same task as well as in the other task. Our results provide the first evidence for a single high-dimensional structured representation of a naturalistic stimulus set that guides behavior in multiple tasks. Moreover, the representations estimated by cognitive tomography can provide independent, behavior-based regressors for elucidating the neural correlates of complex naturalistic priors. © 2013 The Authors.

Differential expression of two Carassius auratus Mx genes in cultured CAB cells induced by grass carp hemorrhage virus and interferon

UV-inactivated GCHV (grass carp hemorrhage virus) is able to induce an antiviral state in cultured CAB cells (crucian carp Carassius auratus blastulae embryonic cells) via the production of interferon (IFN). In the current work, the full-length cDNAs of two Mx genes, termed CaMx1 and CaMx2, have been cloned and sequenced from UV-inactivated GCHV-infected and still IFN-producing CAB cells by suppression subtractive hybridization. Their putative proteins show the characteristically structural features of mammalian IFN-induced Mx proteins, including GTP-binding motif, dynamin family signature and leucine zipper motif. CaMx1 exhibits 85% sequence identity to zebrafish MxA and 72-74% to three Atlantic salmon Mx proteins. CaMx2 is most similar to zebrafish MxE, with 80% identity, and then rainbow trout Mx3, with 52%. Constitutive expression was detected by RT-PCR for CaMx1, but not for CaMx2, in normal CAB cells, but their up-regulations could be induced after treatment with active GCHV, UV-inactivated GCHV and CAB IFN. Distinct kinetics of expression was observed for either CaMx1 or CaMx2 corresponding to the three stimuli, and even between CaMx1 and CaMx2, corresponding to the same stimulus. Upon virus infection, the transcriptional induction was strongly blocked for CaMx2 by cycloheximide (CHX), whereas almost nothing was observed for CaMx1. By contrast, following treatment with CAB IFN, CHX did not inhibit either gene transcription. Collectively, these results suggest that there are very distinct mechanisms for modulating the expression of both CaMx1 and CaMx2 in normal and GCHV-infected CAB cells.

The role of sense organs in the feeding behaviour of Chinese perch

Experiments were conducted to identify the rules of the individual sense organs in the feeding behaviour of Chinese perch Siniperca chuatsi by determining the consumption of natural food after selective removal or blocking of eyes, lateral lines and olfactory organs, and also by observing the behavioural response to visual, mechanical and chemical stimulation by artificial prey. Chinese perch were able to feed properly on live prey fish when either eyes or lateral lines were intact or functional, but could scarcely feed without these two senses. Chinese perch recognized its prey by vision through the perception of motion and shape, and showed a greater dependence on vision in predation when both visual and mechanical cues were available. Chemical stimulation by natural food could not elicit any feeding response in Chinese perch, and gustation was only important to the fish for the last stage of food discrimination in the oropharyngeal cavity. The sensory basis of Chinese perch in feeding is well adapted to its nocturnal stalking hunting strategy. and also explains its peculiar food habit of accepting live prey fish only and refusing dead prey fish or artificial diets. (C) 1998 The Fisheries Society of the British Isles.

Hg胁迫对两种基因型小麦生长及其过氧化物酶活性的影响

用不同浓度Hg处理两种基因型小麦种子,较低浓度的Hg对小麦种子萌发影响比较小,对抗旱品种的小麦种子(陕合)的萌发有略微的刺激作用。小剂量、短时间的重金属处理可以提高POD的活性,发芽后受到Hg胁迫的陕合对Hg的耐受性低于发芽前就受到Hg胁迫的陕合,也低于同样胁迫处理的小麦品种(郑引)。发芽后进行Hg胁迫处理情况下,陕合对于Hg胁迫比较敏感,POD活性随着Hg浓度的升高而下降;而郑引,低浓度Hg对其POD活性有促进作用。在小麦发芽前就受到Hg胁迫的情况下,陕合和郑引的POD活性都随着Hg浓度增加表现为先上升而后下降趋势。

A NOVEL ODOR SENSOR COATED WITH A LIPID-MEMBRANE

In this paper, an interdigital electrode lipid film odour sensor (ILOS) is designed, fabricated and tested. It is made from a microfabricated chemiresistor coated with a synthetic multibilayer film. Nine odorants in gas phase at room temperature have been detected using the odour sensor. For most of the odorants, the relation between the response of the ILOS and odorant concentration obeys Stevens' power law, and there is a good correlation between the minimum odorant concentrations that give rise to a change of the sensor's conductance and human olfactory thresholds.

RESEARCH ON ELECTRICAL-PROPERTIES OF AMPHIPHILIC LIPID-MEMBRANES BY MEANS OF INTERDIGITAL ELECTRODES

Lipids are the main component of all cell membranes and also important mimetic materials. Moreover, it was found recently that they can be used as sensitive membranes for olfactory and taste sensors. Hence the understanding of lipid resistance is important both in sensors and in life sciences. Thirteen lipids were examined by means of interdigital electrodes with narrow gaps of 20-50 mu m, made by IC technology. The membrane lateral resistance in air, resisting electrical voltage, the influence of impurities on resistance and the resistance change in acetic acid vapour are presented for the first time. It is shown that the electrical resistivity for self-assembling lipids depends on their duration of being in an electric field and the content of the conductive impurities. The interdigital electrode is a transducer as well as a powerful tool for researching biomaterials and mimicking materials. The conducting mechanism of lipids is discussed. This method is also suitable for some polymer membranes.

Electro-mass multi odor sensor

For an olfactory sensor or electronic nose the task is not only to detect the object concentration, but also to recognize it. It is well known that all the elements can be identified by their charge to mass ratio e+/m. We tried to use this principle for molecular recognition. Two kinds of sensors are used simultaneously in testing. One is Quartz Crystal Microbalance (QCM) for detecting the change in mass, the other is Interdigital Electrode (IE) for detecting the change in conduction. In this paper the principle and the feasibility of this method are reported. The preliminary results on the recognition of alcohols are presented. The multisensor can be used as an instrument for research on material properties and kinetic process as well.

1、蜜蜂嗅觉学习记忆应用基础研究 2、吗啡和胆碱能拮抗剂联合给药对小鼠Y迷宫空间记忆提取及活动性的影响

一、蜜蜂嗅觉学习记忆应用基础研究特殊气味的探测在刑侦工作中意义重大，常用的警犬探测和仪器分析都有其局限之处。蜜蜂嗅觉灵敏，且学习记忆能力突出，具有为刑侦工作所用的潜力。基于此，我们希望通过训练蜜蜂将其对糖水奖励的伸喙反应与指定气味建立条件反射的原理，配合适当的训练方法，达到利用蜜蜂探测危险气味的目的。在实验中，我们首先比较了不同喂养方式的蜜蜂在气味学习中的差别。由于低浓度气味无法直接使蜜蜂建立条件化，我们采用了逐渐降低气味浓度的方法，成功训练蜜蜂对低浓度(3.6×10-7) 醋酸气味建立了条件反射。结果如下： 1)自然放养与人工孵化两种不同喂养方式的蜜蜂，各两组，分别学习醋酸CS+/薄荷CS-，或柠檬CS+/薄荷CS-的气味配对。以“获得(CS+)，巩固(CS-/CS+ CS+/CS- CS-/CS+)，检测，干净空气假阳性检测”的顺序操作。结果显示自然放养蜜蜂对醋酸气味没有偏好（第一次给醋酸气味伸喙率：6%），学习醋酸气味能力较低（24小时后检测正确率：66%， n=25），相对应，该类蜜蜂对柠檬气味显示出明显偏好(第一次给柠檬气味伸喙率：41%，P< 0.01)，而学习效果（检测正确率：50%，n=20）与醋酸组相近(P>0.05)。人工孵化的蜜蜂对醋酸气味学习能力较自然放养蜜蜂大大提高（检测正确率：96%, n=32， P<0.01），同时对柠檬的学习结果（检测正确率：80%, n=32）也明显提高(0.01

慢性阿片类物质滥用对空间认知功能的影响及嗅觉系统与吗啡成瘾的相互作用

中文摘要 　 Ⅰ　慢性阿片类物质滥用对空间认知功能的影响本章首先对成瘾的神经生物学机制进行综述，然后介绍我的实验研究内容，实验目的是探讨海马在阿片类成瘾中的作用，及阿片类物质滥用对空间认知功能的影响。实验1采用单细胞记录技术，记录自由活动大鼠在慢性吗啡给予后戒断期间海马CA1区神经元发放频率，比较其在吗啡相关环境（阳性环境）及无关环境（阴性环境）中神经元发放频率的变化，且比较神经元发放变化率在各组间的差异。实验2检测了在海洛因戒断初期海洛因依赖者的地图/图标跟随及地图/图标工作记忆的能力。实验3采用Y迷宫行为范式检测在戒断不同时期，慢性吗啡给予对小鼠Y迷宫空间识别能力的影响。实验结果如下：实验1：吗啡戒断后，大鼠海马CA1区部分神经元在阳性环境及阴性环境中的发放率有显著性差异，这些神经元分为两类：Ⅰ类神经元在阳性环境中发放频率高于在阴性环境，Ⅱ类神经元在阳性环境中发放频率低于在阴性环境，其中吗啡组的Ⅱ类神经元发放变化率与盐水组相比存在显著性差异。实验2：海洛因依赖者，尤其女性海洛因依赖者，在地图跟随及地图/图标工作记忆中的成绩明显低于正常被试。实验3：在吗啡戒断第2天、第9天、第19天，小鼠Y迷宫空间识别记忆能力均受到损伤。以上实验结果表明，海马神经元在吗啡相关环境与无关环境中发放频率不同，从而编码了环境刺激与药物经历相关的记忆，在阿片类药物成瘾中起到一定作用；以及阿片类物质滥用损伤了大脑空间认知功能。 Ⅱ　嗅觉系统与吗啡成瘾的相互作用本章首先对嗅觉系统的功能及脑疾病引起嗅觉功能异常进行了综述，然后介绍我的实验研究内容，实验目的是探讨嗅觉系统在吗啡成瘾过程中的作用，及慢性吗啡给予对嗅觉功能的影响。实验1：利用条件化位置偏好模型（CPP），研究气味线索对吗啡依赖及渴求的影响。结果发现，单一嗅觉刺激使小鼠建立条件化位置偏好，形成吗啡依赖。当改变外界环境，动物进入完全新异的环境，依然寻求与吗啡相关的气味线索，说明吗啡相关气味线索能有效诱发小鼠对吗啡的渴求。实验2：研究短期及长期吗啡给予后小鼠嗅觉功能的变化。结果发现， 4天或21天的吗啡给予导致小鼠嗅觉敏感度降低（嗅觉阈值升高），而嗅觉辨别能力没有显著影响。小鼠嗅觉记忆能力受到损伤，随着吗啡给予时间的延长，这种记忆损伤更加明显。我们的实验表明嗅觉系统在吗啡依赖及渴求过程起到非常重要的作用，吗啡成瘾导致部分嗅觉功能的损伤。与药物相关的环境线索是诱发渴求及复吸的原因之一，因此，至少在啮齿类动物模型上，用嗅觉刺激作为药物相关的环境线索来研究渴求及复吸的机制，可能是较好的研究方法。

Oligoaniline-Functionalized terpyridine ligands and their ruthenium(II) complexes: synthesis, spectroscopic property and redox behaviors

A series of oligoaniline-functionalized mono- and bis-topic terpyridine ligands, i.e. C6H5[N(R)C6H4](n)TPY (R = H, butyl, tert-butyloxycarbonyl; n = 1-4; TPY = 2,2':6',2"-terpyridyl) and TPYC6H4[N(R)C6H4](m)TPY (R = H, tert-butyloxycarbonyl; m = 2, 4), and the corresponding monoand bis-nuclear ruthenium(II) complexes have been synthesized and verified. The spectroscopic results indicate that two kinds of pi-pi* transitions from TPY and oligoaniline fragments of ligands strongly shift to lower energy, and the metal-to-ligand charge-transfer transition ((MLCT)-M-1) bands of all obtained complexes are considerably red-shifted (Delta lambda(max) = 22-64 nm) and their intensities become much more intense (approximately 4-6 times), compared with those of the reported complex [Ru(TPY)(2)](2+). Moreover, the spectroscopic properties of the ligands and complexes with longer oligoaniline units (n = 3, 4) are markedly influenced by the external stimulus, such as the oxidation and proton acid doping.

Characterization and property of DNA incorporated bilayer lipid membranes

Calf-thymus DNA-incorporated bilayer lipid membranes supported on a glassy carbon (GC) electrode was prepared by making layers of phosphatidylcholine dimyristoyl (DMPC) on GC electrode. DNA in the BLM was characterized by cyclic voltammetry, IR and AFM, and lipid layers formed on the GC electrode were demonstrated to be a bilayer lipid membrane by electrochemical impedance experiment. In IR and AFM experiments the findings indicated that DNA was incorporated into BLM. The ion channel of bilayer lipid membranes incorporated was studied. The result showed that the ion channel was opened in the presence of the stimulus quinacrine. In the absence of quinacrine the channel was switched. The process can repeat itself many times. The impedance spectroscopy measurements demonstrate that the stimulus quinacrine opens the channel for permeation of marker ion. The mechanism of forming an ion channel was investigated.