Memory for Expectation-Violating Concepts: The Effects of Agents and Cultural Familiarity

Previous research has shown that ideas which violate our expectations, such as schema-inconsistent concepts, enjoy privileged status in terms of memorability. In our study, memory for concepts that violate cultural (cultural schema-level) expectations (e.g., “illiterate teacher”, “wooden bottle”, or “thorny grass”) versus domain-level (ontological) expectations (e.g., “speaking cat”, “jumping maple”, or “melting teacher”) was examined. Concepts that violate cultural expectations, or counter-schematic, were remembered to a greater extent compared with concepts that violate ontological expectations and with intuitive concepts (e.g., “galloping pony”, “drying orchid”, or “convertible car”), in both immediate recall, and delayed recognition tests. Importantly, concepts related to agents showed a memory advantage over concepts not pertaining to agents, but this was true only for expectation-violating concepts. Our results imply that intuitive, everyday concepts are equally attractive and memorable regardless of the presence or absence of agents. However, concepts that violate our expectations (cultural-schema or domain-level) are more memorable when pertaining to agents (humans and animals) than to non-agents (plants or objects/artifacts). We conclude that due to their evolutionary salience, cultural ideas which combine expectancy violations and the involvement of an agent are especially memorable and thus have an enhanced probability of being successfully propagated.     

Influence of Stimuli Spatial Proximity on a SSVEP-Based BCI Performance

Objective: Steady-State Visual Evoked Potentials based Brain-Computer Interfaces (SSVEP-based BCIs) systems have been shown as promising technology due to their short response time and ease of use. SSVEP-based BCIs use brain responses to a flickering visual stimulus as an input command to an external application or device, and it can be influenced by stimulus properties, signal recording, and signal processing. We aim to investigate the system performance varying the stimuli spatial proximity (a stimulus property).Material and methods: We performed a comparative analysis of two visual interface designs (named cross and square) for an SSVEP-based BCI. The power spectrum density (PSD) was used as feature extraction and the Support Machine Vector (SVM) as classification method. We also analyzed the effects of five flickering frequencies (6.67, 8.57, 10, 12 e 15 Hz) between and within interfaces.Results: We found higher accuracy rates for the flickering frequencies of 10, 12, and 15 Hz. The stimulus of 10 Hz presented the highest SSVEP amplitude response for both interfaces. The system presented the best performance (highest classification accuracy and information transfer rate) using the cross interface (lower visual angle).Conclusion: Our findings suggest that the system has the highest performance in the spatial proximity range from 4° to 13° (visual angle). In addition, we conclude that as the stimulus spatial proximity increases, the interference from other stimuli reduces, and the SSVEP amplitude response decreases, which reduces system accuracy. The inter-stimulus distance is a visual interface parameter that must be chosen carefully to increase the efficiency of an SSVEP-based BCI.     

Some Responses of Tsetse Flies to Visual and Olfactory Stimuli

HISTOCHEMICAL fluorescence experiments, using the modifications^1,2 of the formaldehyde condensation procedure described by Falck et al.³, are increasingly common. The procedures for demonstrating monoamines in freeze-dried tissue, require that the sections cut from formaldehyde gas-treated tissue be kept away from water and so the conventional heated water bath for relaxing the cut paraffin sections cannot be used. Acetonitrile⁴ and liquid paraffin⁵ have been utilized and some laboratories even use a heated mercury bath (S. Norr, personal communication), although what is desired is a very non-reactive liquid. ‘Fluorinert Electronic Liquids FC-75, FC-77’ (3M Company, St Paul, Minnesota 55101) adequately replace the water bath. At 45° C these two clear liquids allow cut sections to be handled in the same manner as in the conventional water bath. Other liquids in this series can probably be chosen to give similar characteristics at other bath temperatures, although they have not been tried. A bath with intermediate qualities could be made as the liquids in the series are completely miscible with one another. The ‘Fluorinert Electronic Liquids’ are stated by their manufacturer to be very non-reactive and to have very low water and oil solubilities. The inertness of these liquids suggests that they may also be used to float sections as they are cut and to immerse freeze-dried tissue for storage.     

Effects of AKAP5 Pro100Leu Genotype on Working Memory for Emotional Stimuli

Recent investigations addressing the role of the synaptic multiadaptor molecule AKAP5 in human emotion and behavior suggest that the AKAP5 Pro100Leu polymorphism (rs2230491) contributes to individual differences in affective control. Carriers of the less common Leu allele show a higher control of anger as indicated by behavioral measures and dACC brain response on emotional distracters when compared to Pro homozygotes. In the current fMRI study we used an emotional working memory task according to the n-back scheme with neutral and negative emotional faces as target stimuli. Pro homozygotes showed a performance advantage at the behavioral level and exhibited enhanced activation of the amygdala and fusiform face area during working memory for emotional faces. On the other hand, Leu carriers exhibited increased activation of the dACC during performance of the 2-back condition. Our results suggest that AKAP5 Pro100Leu effects on emotion processing might be task-dependent with Pro homozygotes showing lower control of emotional interference, but more efficient processing of task-relevant emotional stimuli.     

脑源性神经生长因子对老龄鼠智能影响的探讨

目的研究脑源性神经营养因子（bDNF）改善痴呆老龄鼠学习记忆的作用机制;胆碱乙酰转移酶活性（ChAT-IR）、胆碱酯酶（AchE）活性的影响。方法利用海马内注射bDNF及免疫组织化学技术,观察给药前后各组迷宫试验,胆碱乙酰转移酶（ChAT）、胆碱酯酶（AchE）活性的变化。结果治疗组学习记忆能力有明显改变（P〈0.05）。与对照组比较ChAT-IR表达明显增加（P〈0.01）,AchE活性明显增强（P〈0.01）。结论bDNF使胆碱乙酰转移酶活性（ChAT）、胆碱酯酶（AchE）活性增强;对老龄鼠的智能有改善作用。     

情绪刺激影响源记忆的理论模型与研究进展

源记忆是对信息来源(例如信息获取的媒介和感觉通道)的记忆.情绪刺激是能使个体产生正性或负性情绪的刺激.已有研究所揭示的情绪刺激对源记忆的影响不尽相同.综合情绪刺激对源记忆影响的研究成果,阐述注意资源缩减理论和优先捆绑理论,并基于情绪刺激增强、减弱和不影响源记忆三种实验现象总结现有相关实验研究,指出现有研究存在的局限,并对未来研究进行展望.     

外源性神经生长因子对痴呆老龄鼠学习和记忆能力影响的初步探讨

目的探讨外源性神经生长因子（NGF）对痴呆老龄鼠智能影响的机制。方法本实验选用18月龄ICR小鼠45只，应用整体实验和免疫组织化学技术，观察给药前后各组迷宫试验、胆碱乙酰转移酶活性（chAT-IR）、神经生长因子抗体（Anti-NGF）在相关脑区的表达并进行统计学分析。结果用药后学习及记忆能力有明显改善（P〈0．05），与用药前比较ChAT-IR明显增加（P〈0．01），NGF抗体表达明显增加（P〈0．01）。结论外源性NGF对痴呆老龄鼠的智能有改善作用；能够使相关脑区ChAT-IR增加；相关脑区Anti-NGF表达增加；外源性NGF能够保护、支持、修复神经原。     

Interactions between Males of the Lizard Liolaemus tenuis: Roles of Familiarity and Memory

For territorial organisms, recognition of familiar individuals can reduce the frequency and intensity of aggressive encounters (‘dear enemy’ phenomenon), stabilize social systems, and reduce the cost of territory maintenance. Here, we investigated the behavioural events displayed during contests between familiar and unfamiliar individuals in the lizard Liolaemus tenuis (Liolaemidae), a species in which males are territorial. The behaviours recorded were attack, warning, evasion, and submission, and the latencies to the first aggressive (attack or warning) behaviour. Additionally, we assessed the ability of individuals to remember a familiar conspecific after a period without social interaction. Individual males reduced and delayed aggressive behaviour directed towards socially familiar individuals compared with unfamiliar ones. These results suggest that males distinguished between familiar and unfamiliar conspecific males and are in agreement with the ‘dear enemy’ phenomenon. Other behaviours were similar in the contests between familiar and unfamiliar individuals. Recognition of familiar conspecifics was lost after 20 d without social interactions. This may be relevant for interactions with floater males or with neighbours that lose their territory and subsequently attempt to fight for their ex‐neighbour's territory.     

The Combined Effects of Ethanol and Amphetamine Sulfate on Performance of Human Subjects

The combined effects of ethanol and amphetamine on the performance of selected tests were evaluated. No differences were shown between the effects of ethanol-amphetamine and ethanol-lactose on the performance of balance, skipping, Minnesota manipulation, Purdue peg board, Maudsley Personality Inventory, pursuit rotor or digit span tests; but ethanol plus amphetamine produced less impairment of performance of coding, mental addition, and trail making tests than did ethanol plus a placebo. Ethanol increased the errors in performance of the Wonderlic Personnel Test, but the simultaneous administration of amphetamine did not reduce this effect. Conversely, amphetamine reduced the test-retest reliability of the Wonderlic Personnel Test, but alcohol appeared to counteract this effect of amphetamine. These experiments indicate that, when ethanol and amphetamine are used together, each drug modifies some of the effects produced by the other in a manner that cannot be predicted on the assumption that a depressant versus stimulant competition is operative.     

Consolidation of an Olfactory Memory Trace in the Olfactory Bulb Is Required for Learning-Induced Survival of Adult-Born Neurons and Long-Term Memory

Background

It has recently been proposed that adult-born neurons in the olfactory bulb, whose survival is modulated by learning, support long-term olfactory memory. However, the mechanism used to select which adult-born neurons following learning will participate in the long-term retention of olfactory information is unknown. We addressed this question by investigating the effect of bulbar consolidation of olfactory learning on memory and neurogenesis.

Methodology/Principal Findings

Initially, we used a behavioral ecological approach using adult mice to assess the impact of consolidation on neurogenesis. Using learning paradigms in which consolidation time was varied, we showed that a spaced (across days), but not a massed (within day), learning paradigm increased survival of adult-born neurons and allowed long-term retention of the task. Subsequently, we used a pharmacological approach to block consolidation in the olfactory bulb, consisting in intrabulbar infusion of the protein synthesis inhibitor anisomycin, and found impaired learning and no increase in neurogenesis, while basic olfactory processing and the basal rate of adult-born neuron survival remained unaffected. Taken together these data indicate that survival of adult-born neurons during learning depends on consolidation processes taking place in the olfactory bulb.

Conclusion/Significance

We can thus propose a model in which consolidation processes in the olfactory bulb determine both survival of adult-born neurons and long-term olfactory memory. The finding that adult-born neuron survival during olfactory learning is governed by consolidation in the olfactory bulb strongly argues in favor of a role for bulbar adult-born neurons in supporting olfactory memory.     

蘑菇体-昆虫嗅觉学习和记忆中心

蘑菇体(革形体)是昆虫脑内非常重要的一个结构,构成蘑菇体的冠和叶在不同目昆虫中高度分化,其结构虽然保守,但形态上的变化在一定程度上反映了昆虫的进化地位.冠是触角叶嗅觉投射神经元的主要投射区,叶通过输出神经元联系蘑菇体与其它脑区.冠和叶在嗅觉记忆中不可或缺,垂直叶(α叶)支持长时记忆,中叶(γ叶)支持短时记忆.蘑菇体对嗅觉记忆的形成尤其是记忆的再现(提取)具有重要作用.乙酰胆碱(Ach)、γ-氨基丁酸(GABA)和一氧化氮(NO)等是蘑菇体嗅觉突触传递的主要神经递质.蘑菇体内的第二信使系统cAMP-PKA途径和NI-cGMP途径在嗅觉学习和记忆中起基础性作用.     

Consequences of a Human TRPA1 Genetic Variant on the Perception of Nociceptive and Olfactory Stimuli

Background

TRPA1 ion channels are involved in nociception and are also excited by pungent odorous substances. Based on reported associations of TRPA1 genetics with increased sensitivity to thermal pain stimuli, we therefore hypothesized that this association also exists for increased olfactory sensitivity.

Methods

Olfactory function and nociception was compared between carriers (n = 38) and non-carriers (n = 43) of TRPA1 variant rs11988795 G>A, a variant known to enhance cold pain perception. Olfactory function was quantified by assessing the odor threshold, odor discrimination and odor identification, and by applying 200-ms pulses of H₂S intranasal. Nociception was assessed by measuring pain thresholds to experimental nociceptive stimuli (blunt pressure, electrical stimuli, cold and heat stimuli, and 200-ms intranasal pulses of CO₂).

Results

Among the 11 subjects with moderate hyposmia, carriers of the minor A allele (n = 2) were underrepresented (34 carriers among the 70 normosmic subjects; p = 0.049). Moreover, carriers of the A allele discriminated odors significantly better than non-carriers (13.1±1.5 versus 12.3±1.6 correct discriminations) and indicated a higher intensity of the H₂S stimuli (29.2±13.2 versus 21±12.8 mm VAS, p = 0.006), which, however, could not be excluded to have involved a trigeminal component during stimulation. Finally, the increased sensitivity to thermal pain could be reproduced.

Conclusions

The findings are in line with a previous association of a human TRPA1 variant with nociceptive parameters and extend the association to the perception of odorants. However, this addresses mainly those stimulants that involve a trigeminal component whereas a pure olfactory effect may remain disputable. Nevertheless, findings suggest that future TRPA1 modulating drugs may modify the perception of odorants.     

Effects of Acute Lorazepam Administration on Aminergic Activity in Normal Elderly Subjects: Relationship to Performance Effects and Apolipoprotein Genotype

The effects of acute lorazepam challenges on plasma (p) HVA, MHPG, and 5-HIAA, and their relationship to drug-induced cognitive and motor deficits and the apolipoprotein (APOE)-epsilon4 allele were examined. Eighteen healthy elderly (8 epsilon4 carriers) received placebo or acute oral lorazepam doses (0.5 mg or 1 mg) in random sequence, 1-week apart. Cognitive assessment and plasma levels of pHVA, pMHPG, and p5-HIAA were determined at baseline and at 1, 2.5, and 5 h postchallenge. There was no drug-to-placebo difference in monoamine levels and no consistent relationship between changes in monoamine levels and cognitive performance, regardless of epsilon4 status. However, the 1.0 mg dose increased p5-HIAA in epsilon4 carriers, whereas it caused a reduction in noncarriers. Higher baseline pMHPG and p5-HIAA levels were associated with better baseline memory. The epsilon4 allele may modulate the effect of lorazepam on p5-HIAA, but further studies are needed to confirm this finding and elucidate its possible significance.     

Irrelevant Stimuli and Action Control: Analyzing the Influence of Ignored Stimuli via the Distractor-Response Binding Paradigm

Selection tasks in which simple stimuli (e.g. letters) are presented and a target stimulus has to be selected against one or more distractor stimuli are frequently used in the research on human action control. One important question in these settings is how distractor stimuli, competing with the target stimulus for a response, influence actions. The distractor-response binding paradigm can be used to investigate this influence. It is particular useful to separately analyze response retrieval and distractor inhibition effects. Computer-based experiments are used to collect the data (reaction times and error rates). In a number of sequentially presented pairs of stimulus arrays (prime-probe design), participants respond to targets while ignoring distractor stimuli. Importantly, the factors response relation in the arrays of each pair (repetition vs. change) and distractor relation (repetition vs. change) are varied orthogonally. The repetition of the same distractor then has a different effect depending on response relation (repetition vs. change) between arrays. This result pattern can be explained by response retrieval due to distractor repetition. In addition, distractor inhibition effects are indicated by a general advantage due to distractor repetition. The described paradigm has proven useful to determine relevant parameters for response retrieval effects on human action.     

Influence of Dietary Experience on the Induction of Preference of Adult Moths and Larvae for a New Olfactory Cue

In Lepidoptera, host plant selection is first conditioned by oviposition site preference of adult females followed by feeding site preference of larvae. Dietary experience to plant volatile cues can induce larval and adult host plant preference. We investigated how the parent’s and self-experience induce host preference in adult females and larvae of three lepidopteran stem borer species with different host plant ranges, namely the polyphagous Sesamia nonagrioides, the oligophagous Busseola fusca and the monophagous Busseola nairobica, and whether this induction can be linked to a neurophysiological phenotypic plasticity. The three species were conditioned to artificial diet enriched with vanillin from the neonate larvae to the adult stage during two generations. Thereafter, two-choice tests on both larvae and adults using a Y-tube olfactometer and electrophysiological (electroantennography [EAG] recordings) experiments on adults were carried out. In the polyphagous species, the induction of preference for a new olfactory cue (vanillin) by females and 3^rd instar larvae was determined by parents’ and self-experiences, without any modification of the sensitivity of the females antennae. No preference induction was found in the oligophagous and monophagous species. Our results suggest that lepidopteran stem borers may acquire preferences for new olfactory cues from the larval to the adult stage as described by Hopkins’ host selection principle (HHSP), neo-Hopkins’ principle, and the concept of ‘chemical legacy.’     

游泳运动对APP/PS1转基因小鼠学习记忆能力的影响

探讨游泳运动对APP/PS1转基因小鼠学习记忆能力的影响。选择11月龄的雄性APP/PS1转基因小鼠,随机平均分为对照组和游泳组,对照组常规饲养而游泳组进行1个月的游泳运动训练。分别采用刚果红染色、Tunel检测、Western Blot和Morris水迷宫等实验方法观察小鼠大脑皮层Aβ斑形成、神经元凋亡、线粒体生成相关蛋白表达和学习记忆能力的变化情况。结果发现,游泳运动可以减少APP/PS1转基因小鼠大脑皮层Aβ斑的形成、抑制神经元凋亡、促进线粒体生成、增强小鼠的学习记忆能力。由此可见,游泳运动可作为一项防治阿尔茨海默病的行为治疗候选方案。     

Extracting Behaviorally Relevant Traits from Natural Stimuli: Benefits of Combinatorial Representations at the Accessory Olfactory Bulb

For many animals, chemosensation is essential for guiding social behavior. However, because multiple factors can modulate levels of individual chemical cues, deriving information about other individuals via natural chemical stimuli involves considerable challenges. How social information is extracted despite these sources of variability is poorly understood. The vomeronasal system provides an excellent opportunity to study this topic due to its role in detecting socially relevant traits. Here, we focus on two such traits: a female mouse’s strain and reproductive state. In particular, we measure stimulus-induced neuronal activity in the accessory olfactory bulb (AOB) in response to various dilutions of urine, vaginal secretions, and saliva, from estrus and non-estrus female mice from two different strains. We first show that all tested secretions provide information about a female’s receptivity and genotype. Next, we investigate how these traits can be decoded from neuronal activity despite multiple sources of variability. We show that individual neurons are limited in their capacity to allow trait classification across multiple sources of variability. However, simple linear classifiers sampling neuronal activity from small neuronal ensembles can provide a substantial improvement over that attained with individual units. Furthermore, we show that some traits are more efficiently detected than others, and that particular secretions may be optimized for conveying information about specific traits. Across all tested stimulus sources, discrimination between strains is more accurate than discrimination of receptivity, and detection of receptivity is more accurate with vaginal secretions than with urine. Our findings highlight the challenges of chemosensory processing of natural stimuli, and suggest that downstream readout stages decode multiple behaviorally relevant traits by sampling information from distinct but overlapping populations of AOB neurons.