Interference and auditory short-term memory in the bottlenosed dolphin

Interference in auditory short-term memory in the bottlenosed dolphin,Tursiops truncatus (Montagu), was studied using a delayed matching-to-sample task. At each trial, one of two sample sounds, chosen randomly, was projected underwater for 4 sec and then, after a variable delay interval, both sounds were presented. A response to the sound matching the initial sample was reinforced. Correct matching was significantly reduced following short intervals between trials in combination with long delays after the sample (proactive interference), or when a near continuous irrelevant sound was inserted into the delay interval (retroactive interference). There was rapid habituation to interference if the irrelevant sound was short in duration relative to the delay interval. For both proactive and retroactive interference, the errors were predominantly responses to the sample sound appropriate to the prior trial rather than to the current trial, indicating that memory for the relative recency of events (temporal memory) was degraded by interference. When interference was deleted or minimized, temporal memory remained nearly perfect over 30-sec delay intervals, the longest tested. The importance of distinguishing between temporal memory and nontemporal, or event, memory in different forms of the delayed matching task was emphasized.     

Symbolic,identity, and probe delayed matching of sounds by the bottlenosed dolphin

The short-term memory for sounds of the bottlenosed dolphin was tested using symbolic, identity, and probe forms of the delayed matching-to-sample (DMS) task. The forms differed in the number (one or two) or nature (symbolic or identity matches of sample sounds) of postdelay test stimuli available as memory retrieval cues. Although symbolic DMS was difficult to learn, the final performance level was approximately equal to that for identity or probe DMS. On all tasks, the dolphin’s responses were above 80% correct through to delays of 90 sec and, in some cases, through to delays of 180 and 240 sec, the “limits” being governed mainly by the dolphin’s reluctance to continue being tested at long delays. Encoding of sample stimuli into their learned symbolic representation was hypothesized to have reduced symbolic DMS to a recognition memory task, resulting in the observed equivalence of performance with the other two recognition memory tasks. The probe DMS results, unlike those for identity or symbolic DMS, showed no significant proactive interference effects from samples of prior trials. Instead, proactive interference was traceable to the probe value of the prior trial. Overall, the auditory DMS data for the dolphin were functionally similar to results reported for monkeys tested on symbolic, identity, and probe visual DMS tasks.     

Learning disabilities and the auditory and visual matching computer program

This study examined whether audiovisual computer training without linguistic material had a remedial effect on different learning disabilities, like dyslexia and ADD (Attention Deficit Disorder). This study applied a pre‐test–intervention–post‐test design with students (N = 62) between the ages of 7 and 19. The computer training lasted eight weeks occurring twice a week for 15 minutes per session. After the training period, an improvement in the auditory‐visual matching test was found. According to the hypothesis of this study, the youngest children with dyslexia would benefit most from the intervention. However, the training had also a positive effect on auditory‐visual matching with older students with dyslexia. Surprisingly, the students with ADD benefited from this intervention. According to the teachers, this intervention had also a positive effect on the students' school behaviour.     

商标本质与视觉符号

商标的本质是一种视觉符号,是用以区别个人或集体所提供的商品及服务的标记.商标与现代符号学有密不可分的关系,现代符号学原理为现代商标设计提供了理论基础,并帮助商标设计者更好地理解标志设计的目的和方法.     

Delayed matching in the pigeon: Interference produced by the prior delayed matching trial

Pigeons’ delayed matching performance on Trial n was examined as a function of whether the correct and incorrect comparison stimuli from Trial n?1 were maintained in the same role on Trial n (positive transitions), were reversed in role on Trial n (negative transitions), or were absent on Trial n (neutral transitions). Relative to neutral transitions, positive transitions did not significantly facilitate performance. Negative transitions, however, produced significant proactive interference on Trial n, and the magnitude of proactive interference was greater when the Trial n retention interval was 1 sec than when it was 0 sec. As the intertriai interval increased from 2 to 10 sec, the amount of interference dissipated. The results suggest that a prior delayed matching trial can serve as a significant source of forgetting but not a significant source of facilitation on an immediately following delayed matching trial.     

Memory for recent actions in the bottlenosed dolphin (Tursiops truncatus): Repetition of arbitrary behaviors using an abstract rule

Little is known about how animals represent their own actions in working memory. We investigated whether bottlenosed dolphins could recall actions they had recently performed and reveal those recollections using an abstract rule. Two dolphins were trained to respond to a specific gestural command by repeating the last behavior performed. Both dolphins proved to be able to repeat a wide variety of behaviors on command and were able to generalize the repeating rule to novel behaviors and situations. One dolphin was able to repeat all 36 behaviors she was tested on, including behaviors involving multiple simultaneous actions and self-selected behaviors. These results suggest that dolphins can flexibly access memories of their recent actions and that these memories are of sufficient detail to allow for reenactments. The repeating task can potentially be used to investigate short-term action and event representations in a variety of species.     

Integration of the visual and auditory networks in dyslexia: a theoretical perspective

In addition to an intrinsic difficulty in reading and spelling, one of the defining characteristics of dyslexia is an enduring and pervasive difficulty in phonological coding, such that dyslexic readers find it particularly challenging to process and manipulate the constituent sounds of a language. Coexistent with this finding is the evidence that some dyslexic readers also demonstrate subtle sensory coding problems in the visual and auditory domains. Few theories have been proposed to unite these different findings within a coherent model of reading. Here the evidence for visual, auditory and phonological coding problems in dyslexia is briefly reviewed, and a hypothesis is proposed for how adequate early sensory coding may be intrinsic to phonological awareness and subsequent reading ability. In this hypothesis, a cortical network is assumed that incorporates the visual, auditory and phonological skills of reading. The visual sub‐component of the network is mediated by the dorsal visual pathway, which is responsible for the accurate spatial encoding of letters, words and text. The auditory component of the network in pre‐readers is intrinsic to the development of phonological sensitivity, and then grapheme‐phoneme assimilation as reading skills develop. In this hypothesis, some of the symptoms of dyslexia may result from subtle problems in the encoding of both visual and auditory information and their role in maintaining the synchronicity of the reading network.     

Developmental differences in visual and auditory processing of complex sentences

Children aged 8 through 11 (N = 250) were given a word-by-word sentence task in both the visual and auditory modes. The sentences included an object relative clause, a subject relative clause, or a conjoined verb phrase. Each sentence was followed by a true-false question, testing the subject of either the first or second verb. Participants were also given two memory span measures: digit span and reading span. High digit span children slowed down more at the transition from the main to the relative clause than did the low digit span children. The findings suggest the presence of a U-shaped learning pattern for on-line processing of restrictive relative clauses. Off-line accuracy scores showed different patterns for good comprehenders and poor comprehenders. Poor comprehenders answered the second verb questions at levels that were consistently below chance. Their answers were based on an incorrect local attachment strategy that treated the second noun as the subject of the second verb. For example, they often answered yes to the question The girl chases the policeman after the object relative sentence The boy that the girl sees chases the policeman. Interestingly, low memory span poor comprehenders used the local attachment strategy less consistently than high memory span poor comprehenders, and all poor comprehenders used this strategy less consistently for harder than for easier sentences.     

Comparison of auditory and visual conditioning stimuli in delay eyeblink conditioning in healthy young adults

Classical eyeblink conditioning (EBC) has been widely used to probe cerebellar function in humans and nonhuman mammals. Although the neural pathways governing behavior in this task are well understood and fairly discrete, it remains unclear in the human literature how conditioned stimuli (CSs) of different modalities (e.g., visual and auditory) influence the exhibition of conditioned responses (CRs). In the present study, therefore, CRs to a visual CS and an auditory CS were examined with the single-cue delay EBC procedure. An initial experiment (N=61) was conducted to identify visual and auditory stimuli that had equal perceived intensities. Using these perceptually equivalent stimuli, a second group of 25 subjects completed auditory and visual EBC procedures in two testing sessions 5–8 days apart. Whereas the acquisition of CRs was similar between the CS modality conditions, the timing of the CRs differed such that earlier CR onset and peak latencies were associated with the visual CS. In addition, CR timing improved across testing sessions, as indicated by the later CR peak latencies exhibited during the second testing session, as compared with the first.     

掺杂剂与基质材料能量匹配的红色有机发光二极管

1　Introduction　Organiclight emittingdiodes(OLEDs)haveattract edconsiderableattentionduetoitsgreatpotentialinefficiency ,low voltage ,large area ,lightweight ,andfull colorflat paneldisplays[1,2 ] .Forfull colordis plays ,itisnecessarytohaveefficientred ,green ,andblueemitterswithappropriatechromaticity .Bycom parisonwiththehighperformanceofblueandgreenOLEDs ,theperformanceandpurechromaticityofredOLEDsarestillrelativelypoor .UsuallyredOLEDsareimprovedbydopingreddyesintohostmaterialswit…     

运用符号标识解混合物组成等题

1　符号标识的应用举例(1)有 10克不纯的ＣａＣＯ3 ,其中可能含ＭｇＣＯ3及Ｋ2 ＣＯ3 ,使其与足量稀盐酸充分反应 ,共得ＣＯ24 .4 4克 ,请据此分析 :Ａ .肯定有ＭｇＣＯ3 ,无Ｋ2 ＣＯ3 ;Ｂ .肯定有ＭｇＣＯ3 ,可能有Ｋ2 ＣＯ3 ;Ｃ .肯定有Ｋ2 ＣＯ3 ,无ＭｇＣＯ3 ;Ｄ .肯定有Ｋ2 ＣＯ3 ,可能有ＭｇＣＯ3 。(2 )有等质量的镁、铁样品分别与足量稀盐酸充分反应 ,经测知产生的Ｈ2 质量相等 ,请分析以下判断 :①Ｍｇ含杂而Ｆｅ为纯净物 ,②两者均含杂且杂质不同 ,③Ｆｅ含杂而Ｍｇ为纯净物 ,④两者均含杂且杂质相同。Ａ .全部正确　　　Ｂ .全部…     

数字化可视三维教材在医学研究生教育创新中的应用探索

随着现代社会的发展,医学教育资源也愈加丰富。及时准确地将世界新技术、医学研究以及医学新学科发展反映在医学研究生教学中极为重要。医学数字化可视三维教材借助计算机技术进步所带来的新兴多媒体教学手段,以其特有的优势将更好地满足新时代研究生对相关医学知识的更高要求,在教学中发挥极大作用。     

多媒体辅助下的课堂讨论模式在专科英语中的运用

国内有关课堂讨论模式的探究主要集中于中小学,对大中专英语的课堂讨论模式的研究相对来说比较少。而且传统的英语静态课堂已不能体现,由此以活,新,实等为特点的动态课堂则很快的适应了这一改革。中专英语课堂教学的创新策略至少应包括以下几个方面:以良好的民主气氛和语言环境激发学习热情;积极开展课堂分组讨论和信息交流;因材施教;运用现代化教学手段,培养学生的自主学习能力。     

时滞反应扩散捕食者-食饵模型的全局渐近稳定性

考虑具有比率依赖的功能反应函数和时滞的反应扩散捕食者-食饵模型。使用单调迭代原理和上下解方法获得了模型正常数稳态解的全局渐近稳定性。     

一类计算机网络病毒模型的稳定性

研究了一类时滞SIRS计算机网络病毒模型。以时滞为参数,通过分析模型相应特征方程根的分布,讨论了模型局部稳定性和Hopf分岔的存在性,并通过仿真实例验证了理论分析结果的正确性。     

Variability of classification by the matching familiar figures test as a function of grade level medians

This study examined the variability of classification by the Matching Familiar Figures Test (MFF) as a function of grade level medians. The MFF was administered to 52 kindergarten and 60 first-grade children, and classification was completed using two sets of medians. The first procedure involved classification based on medians for response time and errors computed from the combined MFF scores of the kindergarten and first-grade children. The second procedure involved clmsification of the same children based on separate medians for each grade. A x² analysis indicated that MFF classification was highly dependent upon which sample medians were used; 18%(N = 20) of the sample failed to maintain the same classification across both procedures. Analysis also revealed that for the majority (65%) of the children change in classification was due to the change in the median error cutoff. The implications of these findings for future MFF research involving young children and the need for standardized norms for the MFF are discussed.     

一种新的模式匹配算法的设计与实现

针对原始模式匹配算法存在的缺陷,本文提出了一种新的匹配算法并编制出C语言源代码程序在机器上加以实现．文章还从理论分析和实际测试两个方面证明了新算法在查找效率上比原算法有了很大的提高。