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1.
The antibiotic chloramphenicol, an inhibitor of mitochondrial protein synthesis, was used to investigate the time-related changes in protein synthesis following passive avoidance training in the day-old chick (white leghorn–black Australorp). Retention of memory for this simple learning task is known to be prevented by an inhibitor of cytosolic protein synthesis, anisomycin, in a biphasic manner, with the first phase of sensitivity occurring up to 90 min post-training and the second phase between 4 and 5 h post-training (Freeman, Rose, & Scholey, 1995). Birds received bilateral intracranial injections of chloramphenicol (10 μl/hemisphere of a 7.4 mM solution) at various times relative to training and were tested 24 h later. This report shows that at the second phase of anisomycin susceptibility there was a chloramphenicol-sensitive period (5 h post-training) which had an onset time less than 1 h after injection. The effect of chloramphenicol appears not to be due to the mitochondria being energetically compromised since intracranial injections of an uncoupler of mitochondrial oxidative phosphorylation, 2,4-dinitrophenol (0.1 mM), did not disrupt memory formation when injected 5 h after training, even though it did cause amnesia when injected at the earlier time point of 20 min post-training. These results are discussed in the context of what is already known about memory formation in the day-old chick.  相似文献   

2.
The effects of a specific presynaptic cholinergic antagonist, toosendanin, on memory formation following a passive avoidance training experience in day-old chicks was investigated. Bilateral injection of toosendanin into the neostriatal/hyperstriatal region of the chick forebrain produced memory impairment in a dose-dependent manner. Retention deficits were apparent from 20 min following training in chicks treated with toosendanin, regardless of the injection time relative to training. Chicks that received injections of the drug at corresponding times prior to retention tests showed normal retention levels, suggesting that toosendanin has no effect on performance and memory retrieval. These results indicate an involvement of cholinergic transmission during an early stage of memory formation.  相似文献   

3.
The antibiotic anisomycin (ANP), a protein synthesis inhibitor, was used to investigate the time-related changes in protein synthesis following passive avoidance training in the day-old chick. Retention of memory for this simple learning task is known to be prevented by protein synthesis inhibitors within the first hour posttraining. Here we report a second, later time window during which inhibition of protein synthesis results in amnesia following one-trial passive avoidance training. Birds were given bilateral intracranial injections of ANI (10 μl/hemisphere of a 30 mM solution) at various times relative to training and tested 24 h later. Injections given between 0.5 h prior to 1.5 h post-training or 4-5 h posttraining, but not at later or at intervening times, resulted in amnesia. These results are discussed in the context of earlier findings, using the inhibitor of glycoprotein synthesis 2-deoxygalactose, that memory formation shows two glycoprotein-synthesis-dependent periods of sensitivity (Scholey, Rose, Zamani, Beck, and Schachner, 1993). The time windows of susceptibility of ANI and 2-Dgal are consistent with a model in which there are two waves of neural activity following training; during the second, commencing 4 h after training, proteins are synthesized and then glycosylated as part of the establishment of an enduring memory trace.  相似文献   

4.
It has been shown previously that the immediate-early genes, c-fos and c-jun mRNA are induced in the 1-day-old chick forebrain after one-trial passive avoidance training in which chicks learn to avoid pecking at a bitter-tasting bead. Here, we have studied the expression of their proteins using antibodies to Fos and Jun. Western blotting disclosed two immunoreactive bands for the anti-Fos antibody (47 and 54 kD) and two immunoreactive bands for the anti-Jun antibody (39 and 54 kD). Two hours post-training there was an increase in the number of Fos-positive stained nuclei in right intermediate medial hyperstriatum ventrale (IMHV) (P<0.01), left IMHV (P<0.05), right lobus parolfactorius (LPO) (P<0.025) and left LPO (P<0.05) of birds trained on the bitter bead compared with controls that had pecked a water-coated bead. Staining for Jun protein was significantly greater in the right LPO of trained chicks (P<0.01). Other forebrain regions showed no increase over quiet control levels. The findings are discussed in the context of the cascade of events involved in passive avoidance memory consolidation in the day-old chick.  相似文献   

5.
《Memory (Hove, England)》2013,21(6):665-687
We investigated the recovery from memory of a primary task after an interruption. If the primary task lacked associative support among its task components, recovery was more difficult following an interruption that overlapped either completely or partially in the amount of information shared with the primary task (an interruption-similarity effect). In addition, memory for completed actions was superior to memory for impending unfinished actions. However, if the primary task had associative support among its task components, there was no adverse effect of interruption similarity, and completed and unfinished actions were recalled equally well. We explore possible explanations and implications of these results.  相似文献   

6.
客体工作记忆任务中大脑皮层活动的记忆负荷效应   总被引:5,自引:0,他引:5  
利用128导事件相关电位技术,采用延迟匹配任务的实验范式,测查了20名正常被试完成不同负荷客体任务时的皮层慢电位(slow cortical potentials,简称sp成分),实验发现:背侧前额叶在刺激呈现后的700ms到1400ms出现记忆负荷效应,高负荷任务诱发的sp成分显著负于低负荷任务;低负荷任务诱发的sp成分在左前额区(500~1800ms)、左前额-中央区(700~1800ms)、左中央-顶叶区(1000~1400s和1800~4800ms)、右前额区(1800~4800ms)和右前额-中央区(1400~4800ms)显著负于高负荷任务,出现记忆负荷效应,但这种负荷效应在左右大脑半球所反映的心理意义可能不同  相似文献   

7.
The visual-spatial memory ability of 25 Zairian elementary school children was compared with that of 23 Scottish children, using a variation of Kearins's (1976) object placement task. The Scottish children demonstrated significantly better visual-spatial memory than the Zairian children when the easiest (small household objects) of three arrays was presented. The Scottish and Zairian children demonstrated a similar level of visual-spatial ability when the other two arrays (geometric shapes and a variety of natural pieces of wood) were presented, and there were no significant gender differences. Although the Australian Aboriginal children's performance on the visual-spatial task in Drinkwater's (1976) study was superior to the White children's performance (Kearins, 1976, 1981), the Zairian children's performance in this study was not. Perhaps the Aboriginal groups, over countless generations navigating the trackless desert of western Australia, were forced by their environment to develop an aptitude for direction finding that Zairians (whose ecological situation more closely resembles that of Europeans) have not.  相似文献   

8.
ABSTRACT. The authors investigated whether working memory (WM) plays a significant role in the development of decision making in children, operationalized by the Children's Gambling Task (CGT). A total of 105 children aged 6–7, 8–9, and 10–11 years old carried out the CGT. Children aged 6–7 years old were found to have a lower performance than older children, which shows that the CGT is sensitive to participant's age. The hypothesis that WM plays a significant role in decision making was then tested following two approaches: (a) an experimental approach, comparing between groups the performance on the CGT in a control condition (the CGT only was administered) to that in a double task condition (participants had to carry out a recall task in addition to the CGT); (b) an interindividual approach, probing the relationship between CGT performance and performance on tasks measuring WM efficiency. The between-groups approach evidenced a better performance in the control group. Moreover, the interindividual approach showed that the higher the participants’ WM efficiency was, the higher their performance in the CGT was. Taken together, these two approaches yield converging results that support the hypothesis that WM plays a significant role in decision making in children.  相似文献   

9.
ABSTRACT

Age differences in memory performances on a conceptually driven task, the category exemplar generation (CEG) test, were investigated. Thirty-six younger adults and 36 healthy older adults studied word lists in full and divided attention conditions. Recall was tested with category names. The process-dissociation procedure was used to derive estimates of controlled and automatic memory. Old-old adults (70–84 years) exhibited poorer conscious recollection than both younger (18–24) and young-old adults (59–69). In contrast, no age differences were found in estimates of automatic memory. For the younger and older adults, the divided encoding manipulation reduced both the consciously controlled and automatic estimates of memory. The results suggest that the few prior findings of age deficits in priming on the CEG may have been an artifact of contamination from conscious retrieval processes. They also indicate that the opportunity for greater semantic processing enhances the conceptual priming of both younger and older adults.  相似文献   

10.
ABSTRACT

A combined working memory/repetition priming task was administered to 13 young (mean age 23) and 13 elderly (mean age 69) adults. Each participant memorized a sample target face at the beginning of a trial and then determined whether each of 13 serially presented test faces matched the sample target. In each trial, both the target and one particular distracter face were repeated during the test phase. Within-trial repetition priming effects indicated the contribution of implicit memory to task performance. Response times decreased as items were tested repeatedly within a trial, but this decrement was greater for distracters than for targets. Young and older participants were equally accurate at identifying targets, but elderly were slightly less accurate for distracters. Elderly participants showed repetition priming effects for both targets and distracters, while the young showed such effects only for distracters. The results suggest that active maintenance in working memory, but not inhibition or rejection of distracters, may suppress implicit memory systems.  相似文献   

11.
Examined attentional deployment of dysphoric, unstable, and stable nondysphoric individuals using the Deployment-of-Attention Task (DOAT) while randomly varying stimulus exposure durations. Previous research indicates a nondepressed “protective” bias in attention whereas depressed individuals evidence no bias. The current study examined the possibility that depressed participants' lack of bias may actually reflect inattention to briefly presented stimuli, possibly due to slowed processing seen in depression (i.e. psychomotor retardation). Participants completed the DOAT, viewing stimuli at four presentation durations randomised across trials. Results indicated that dysphoric participants displayed no attentional bias even at extended presentation durations, whereas nondysphoric participants showed a “protective” bias. Within the nondysphoric group, unstable nondysphoric participants displayed a more pronounced protective bias than did stable nondysphorics.  相似文献   

12.
以往研究主要在长时记忆中考察部分线索效应,很少关注工作记忆中的部分线索效应及其作用机制。本研究采用项目再认任务,考察了工作记忆中提供部分学习项目作为提取线索,对存储在工作记忆中的已有表征的影响。结果发现:有、无部分线索试次分组呈现时,相较于无部分线索条件,有部分线索条件下再认正确率和d'降低,β升高,反应时间延长;有、无部分线索试次随机混合呈现时,有部分线索条件下再认正确率降低,β升高,但反应时间并无显著延长。结果表明:工作记忆中部分线索的提供降低了目标项目的表征强度;研究结果可用提取抑制假说解释,但工作记忆中部分线索的作用可能受注意资源有限性制约。  相似文献   

13.
Decision makers intending to avoid risk in a decision situation can choose a less risky alternative (passive risk avoidance) or intervene actively in an alternative applying a risk‐defusing action (active risk avoidance). In Experiment 1 (64 participants), we compared active and passive risk defusing in two framing conditions. In the negative frame, in the uncertain alternative, a change to the worse was possible; in the positive frame, a change to an improvement was possible. Each participant decided in both framing conditions. As expected, active risk avoidance behavior for preventing a negative outcome (i.e., in the negative frame) was more likely than for promoting a positive one (i.e., in the positive frame). If decision makers did not or could not actively defuse the risk, they chose in correspondence to the classical pattern: risk avoidance in the positive frame and risk seeking in the negative one. We replicated the latter result in a second experiment (32 participants). The classical framing pattern in passive risk avoidance in both experiments is remarkable, because participants were not presented or did not search for exact probabilities. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

14.
The relationship between performance in working memory (WM) span tasks, scholastic skills and fluid intelligence was investigated to determine how WM span is related to higher order cognition. The predictive utility of two WM span tasks differing in the demand of the processing task was studied with controlled presentation times and a broad set of academic criterion tasks. Sixty‐eight adolescents (mean age 16 years) completed two WM span tasks, Raven's Progressive Matrices and several scholastic performance measures. The results showed that the more demanding WM span task predicted fluid intelligence, but did not contribute uniquely in explaining scholastic performance. In contrast, the less demanding WM task predicted scholastic performance. The results suggest that the strength of the relation between WM performance and higher order cognition varies in conjunction with both the demand of the WM span task and the type of higher order cognition measure.Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

15.
Background data, or life history measures, ask people to recall and report prior behavior and experiences. Although these measures have been found to be effective predictors of performance, little is known about the characteristics of items contributing to accurate reporting and good recall. Accordingly, 153 undergraduates were asked to work on a complex, computer-based ‘in-basket’ task. In working through this task, objective indices of their activities were obtained. After completing this task, subjects were asked to answer a set of background data items describing their behavior and experiences during task performance. Additionally, they were asked to return one week later and, again, answer the background data questions. Indices of accuracy and recall consistency were obtained for various item types. In accordance with the literature of autobiographical memory, it was found that people could consistency recall and accurately report general summaries of activities and their reactions to the task. More specific actions or behaviors that were not linked to goals were not accurately and consistently recalled. The implications of these findings for the development and application of background data measures are discussed.  相似文献   

16.
本文采用“模拟星期”范式通过3个实验分别考察了前瞻记忆任务类型的差异以及动机与任务序列对前瞻记忆的影响。结果表明:(1)规律性前瞻记忆任务的正确率显著高于非规律性的,即使本研究条件下对非规律性前瞻记忆任务进行奖励与惩罚,仍没有消除两者间的差异。(2)不论是惩罚还是奖励都可以显著提高非规律性前瞻记忆的成绩,而且动机促进作用会蔓延至非直接强化的前瞻记忆任务。(3)固定序列前瞻记忆成绩显著优于随机序列的,且在实验过程中固定序列前瞻记忆的成绩呈上升趋势,而随机序列的基本不变,固定序列在一定程度上反映了行为习惯的建立过程。(4)不论前瞻记忆任务规律与否,惩罚或奖励,任务序列如何,基于时间的前瞻记忆成绩均优于基于事件的前瞻记忆的成绩。(5)时间确认任务中,被试翻看时钟的次数与其正确率间呈显著正相关,且越临近规定时间翻看次数越多,呈J型分布。  相似文献   

17.
To determine whether working memory (WM) and reference memory (RM) represent different aspects of spatial memory, albino WAG rats and the pigmented Brown Norway rats were tested in the acquisition, retention, and reversal of spatial orientation tasks in the holeboard, which allows the simultaneous assessment of WM and RM. Putative nonmnemonic factors, such as the speed of visiting the holes or the development of a search strategy (preferred sequence of visiting the baited set of holes) were also evaluated because they might influence WM and RM performance. The WM performance of Brown Norway rats was generally worse than that of the WAG rats. The reverse was true for the RM performance. Correlation analysis supported the notion that these two measures are independent. Differences in the speed of visiting the holes and in the development of a preferred sequence of visiting the baited set of holes could not explain the strain differences in WM and RM performance. Because spatial WM and RM appear to be independent measures in the holeboard, this task could be used to investigate whether different neural substrate(s) underlie these two memory components.  相似文献   

18.
双酚A (bisphenol, BPA)是一种广泛应用于塑料制品的环境内分泌干扰物, 具有弱雌激素和抗雄激素活性, 与雌激素受体有一定的亲和力。本实验探讨长期BPA暴露对成年小鼠恐惧记忆的影响及其神经机制。将9周龄雄性小鼠暴露于BPA (0.4、4、40 mg/kg/d) 90 d, 建立小鼠亚慢性BPA暴露模型后, 进行场景性条件恐惧训练, 然后分别在电击后1 hr及24 hr检测小鼠的僵立时间, 同时在电击前、电击后1 hr及24 hr检测海马相关蛋白表达变化。结果表明, BPA (4、40 mg/kg/d)暴露延长小鼠场景性条件恐惧训练后1 hr及24 hr的僵立时间。Western blot蛋白检测结果显示, 行为训练前, BPA降低了小鼠NMDA受体NR1亚基表达水平, 上调组蛋白去乙酰化酶2表达。行为训练后1 hr及24 hr, BPA促进海马NMDA受体亚基NR1和组蛋白H3乙酰化表达, 抑制组蛋白去乙酰化酶2表达, 同时促进ERK1/2磷酸化水平。以上结果表明, 长期BPA暴露提高成年小鼠恐惧记忆获得的同时延长恐惧记忆的保持; 该作用可能通过激活海马的ERK1/2通路而改变核内组蛋白乙酰化和NMDA受体水平进行。  相似文献   

19.
Neurophysiological and behavioral evidence suggests that the prefrontal cortex (PFC) may be sexually differentiated in nonhuman primates. The present study examined whether there are sex differences in working memory in humans that might reflect sexual differentiation of human PFC. Male and female undergraduates were administered a novel multitrial spatial working memory task (SPWM) and a verbal working memory task. In three experiments, females committed significantly fewer working memory errors and took significantly less time to reach criterion than males on the SPWM task. The female advantage was not accounted for by differences in general intellectual ability, attention, perceptual speed, incidental memory, or speed of verbal access. In Study 3, a sex difference was also observed on a measure of verbal working memory. The findings suggest that some prefrontal functions may be sexually differentiated in humans.  相似文献   

20.
Avoidance of culturally diverse peers undermines the benefits of multicultural teams. Using uncertainty reduction theory, we argue that team members’ cultural intelligence (CQ; the capability to work effectively in culturally diverse settings) and language competence (the ability to communicate in a language) exert main and synergistic effects on avoidance behaviors. We further propose that avoidance negatively predicts individuals’ task performance (behaviors that contribute to team outcomes) and voice behaviors (giving suggestions to improve the status quo). Put together, we test a moderated mediation model where the mediating role of avoidance between CQ and outcomes of task performance and voice behaviors is moderated by language competence. Our results, based on data collected from multicultural team members at three time points, showed no main effects of CQ and language competence on avoidance. Instead, we found synergistic effects such that CQ was negatively related to avoidance only when language competence was high. Avoidance was negatively related to peer-rated task performance and voice behaviors. Conditional process analyses supported our moderated mediation hypothesis, suggesting that avoidance explains why people with higher CQ and higher language competence have higher task performance and voice behaviors.  相似文献   

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