Mapping of interactions in the pitch memory store

A technique obtaining a precise mapping of interactive effects in the pitch memory store is described. Subjects were required to compare two tones for pitch when these were separated by a 5-second interval during which six other tones were played. In the second serial position of the intervening sequence there was placed a tone whose pitch bore a critical relationship to the pitch of the first test tone. When the critical intervening tone was identical in pitch to the first test tone, memory facilitation was produced. As the separation in pitch between these two tones increased, errors rose progressively, peaked at a separation of 2/3 tone, and declined roughly to baseline at a whole tone separation. It is concluded that the pitch memory store is arranged logarithmically in a highly ordered and specific fashion.     

Unit activity: motiviation-dependent responses from midbrain neurons

Single neurons in the midbrain tegmentum of rats showed clear discriminatory responses to three tones announcing either food or water or no reinforcement. Subjects were required to press a single lever and remain motionless for 2 seconds during which time unit activity from several brain sites was recorded. One of the tones, randomly designated, was sounded halfway through this period. Manipulation of drive states revealed that the highest activity was associated with tones announcing the reinforcement for which the animal was most strongly motivated. Thus, from a hungry animal sustained or increased firing rates were elicited by a " food" tone and differentially lowered rates by the other tones.     

合肥话连读变调与三字组轻声的优选论分析

连读变调与轻声是官话方言中两种常见现象。传统的看法是两者之间无密切联系。本文采用实验语音学的方法、运用音系学的最新理论—优选论对这两种现象进行了描述与音系分析，获得了具有原则性的统一解释。结果表明标记性制约条件“低调”既适用于连读变调又适用于三字组轻声音高的音系分析，因此两者之间有密切相关。     

长沙方言单字调及变调的实验语音学报告

长沙方言单音节声调及双音节变调的实验语音学研究发现,单音节声调包括阳去21和上声42两个降调和阴平23,阳平13,阴去45,入声24四个升调;没有平调。变调有三种形式:阳去做前字时,调值由21变为22;上声无论做前字或是后字,均由42变为33;入声做后字时,在并列或偏正结构中由24变为33。     

Discrimination of tones during reinforcing brain stimulation

Hungry animals were trained to press a lever for brain stimulation. Different tones were presented concurrently with the stimulation. A second lever delivered food only during critical tone periods. Animals were able to discriminate tones presented concurrently with rewarding intracranial stimulation, and they also interrupted self-stimulation behavior to respond appropriately under other reinforcements.     

Category-specific cortical activity precedes retrieval during memory search

Here we describe a functional magnetic resonance imaging study of humans engaged in memory search during a free recall task. Patterns of cortical activity associated with the study of three categories of pictures (faces, locations, and objects) were identified by a pattern-classification algorithm. The algorithm was used to track the reappearance of these activity patterns during the recall period. The reappearance of a given category's activity pattern correlates with verbal recalls made from that category and precedes the recall event by several seconds. This result is consistent with the hypothesis that category-specific activity is cueing the memory system to retrieve studied items.     

Modulation of memory processing by cholecystokinin: dependence on the vagus nerve

Allowing mice access to food immediately after an aversive training session enhances memory retention. Cholecystokinin-octapeptide (CCK-8), which is a gastrointestinal hormone released during feeding, also enhances memory retention when administered intraperitoneally. This memory-enhancing effect of CCK-8 is blocked when the vagus nerve is cut, indicating that CCK-8 may produce its effect on memory retention by activating ascending fibers in the vagus nerve. Thus, CCK-8, a peripherally acting peptide, may mediate the memory-enhancing effects of feeding.     

Pitch memory: an advantage for the left-handed

In an auditory or musical task, subjects made pitch recognition judgments when the tones to be compared were separated by a sequence of interpolated tones. The left-handed subjects performed significantly better than the right-handed and also had a significantly higher variance. Further analysis showed that the superior performance was attributable largely to the left-handed subjects with mixed hand preference.     

Decay of information in short-term memory

Self-paced recall in Broadbent's simultaneous listening task shows particular temporal patterns associated with report strategies. Accuracy is a decreasing function of the interval between presentation and report of an item, irrespective of report strategy. Results are related to an interaction between strategies of response selection and decay of information from memory.     

Natural occurrence of malaria in rhesus monkeys

A tone ending in unavoidable electric shock was periodically presented to pigeons while they pecked a key for food. When pecking was completely disrupted by tone, shock was disconnected, and the training tone and tones having new frequencies were presented. Initially the gradient of generalization was broad; as testing proceeded, however, the gradient narrowed severely.     

The role of Drosophila mushroom body signaling in olfactory memory

The mushroom bodies of the Drosophila brain are important for olfactory learning and memory. To investigate the requirement for mushroom body signaling during the different phases of memory processing, we transiently inactivated neurotransmission through this region of the brain by expressing a temperature-sensitive allele of the shibire dynamin guanosine triphosphatase, which is required for synaptic transmission. Inactivation of mushroom body signaling through alpha/beta neurons during different phases of memory processing revealed a requirement for mushroom body signaling during memory retrieval, but not during acquisition or consolidation.     

越南留学生汉语声调习得偏误量化及成因分析

汉语声调是区别意义的相对音高,在对外汉语教学中往往成为学生学习的难点。面对目前云南省越南学生逐渐增多的趋势,本文以越南学生汉语声调为研究对象,采用录音与听辨分析相结合的方法,在测试的基础上对该国留学生汉语声调的习得偏误做一些量化分析及解释,并提出了教学方面的对策,以便对越南学生的对外汉语教学及研究提供帮助。     

红碎茶发酵过程中蛋白质组成含量变化规律的研究

本研究探讨了红碎茶发酵过程中简单蛋白质组成和复合蛋白的含量变化规律。在发酵过程中,简单蛋白质含量逐步减少,复合蛋白含量不断增加,两者的含量变化高度相关。发酵叶的简单蛋白质中,谷蛋白占64％左右.发酵过程简单蛋白质的含量减少主要是谷蛋白,占减少总量的66％～72％,其次是醇溶蛋白、白蛋白、球蛋白。研究表明,红碎茶发酵过程能与多酚类及其氧化产物产生结合的蛋白质主要是谷蛋白.发酵叶温高,蛋白质与多酚类的结合作用加强,各类简单蛋白质的减少量和复合蛋白的增加量都明显提高,发酵叶中水溶性多酚类、儿茶素的保留量明显下降。发酵60～80min,蛋白质的结合作用最大.     

Electrical signs of selective attention in the human brain

Auditory evoked potentials were recorded from the vertex of subjects who listened selectively to a series of tone pips in one ear and ignored concurrent tone pips in the other ear. The negative component of the evoked potential peaking at 80 to 110 milliseconds was substantially larger for the attended tones. This negative component indexed a stimulus set mode of selective attention toward the tone pips in one ear. A late positive component peaking at 250 to 400 milliseconds reflected the response set established to recognize infrequent, higher pitched tone pips in the attended series.     

Time-dependent processes in memory storage

These observations indicate that the long-lasting trace of an experience is not completely fixed, consolidated, or coded at the time of the experience. Consolidation requires time, and under at least some circumstances the processes of consolidation appear to be susceptible to a variety of influences- both facilitating and impairing- several hours after the experience. There must be, it seems, more than one kind of memory trace process (31). If permanent memory traces consolidate slowly over time, then other processes must provide a temporary basis for memory while consolidation is occurring. The evidence clearly indicates that trial-to-trial improvement, or learning, in animals cannot be based completely on permanent memory storage. Amnesia can be produced by electroshock and drugs even if the animals are given the treatment long after they have demonstrated "learning" of the task. Of particular interest is the finding that retention of the inhibitory avoidance response increases with time. In a sense this should be expected, for it has long been known (and ignored) that, within limits, learning is facilitated by increasing the interval between repeated trials (7, 30). Our result may be the simplest case of such an effect. Since the improvement in retention with time seemed not to be due solely to consolidation (as indicated by electroshock effects), it would seem that the "distribution of practice" effect, as it is typically designated, may be due in part to a time-dependent temporary memory storage process. In our work with animals we have found no analog of human immediate memory such as that required for repeating digits (or finishing sentences). Animals tested immediately on the task described above after a trial typically showed no evidence of memory. It could be that the poor performance is due to excessive fright, but the "distribution of practice effect" is also typically observed in learning experiments in which food reward is used rather than shock avoidance. Since the retention tasks require the animals to change their behavior in some way, it could well be that the growth of retention over the first few minutes after a trial is due to time dependent processes involved in the organization of processes necessary for changing behavior, in addition to those involved in temporary storage and retrieval. It is worth pointing out that there is evidence of an analogous process in human memory (32). A complex picture of memory storage is emerging. There may be three memory trace systems: one for immediate memory (and not studied in our laboratory); one for short-term memory which develops within a few seconds or minutes and lasts for several hours; and one which consolidates slowly and is relatively permanent. The nature of the durability of the longterm memory trace (that is, the nature and basis of forgetting) is a separate but important issue. There is increasing evidence and speculation (20, 21, 33) that memory storage requires a "tritrace" system, and our findings are at least consistent with such a view. If there are, as seems possible, at least three kinds of traces involved in memory storage, how are they related? Is permanent memory produced by activity of temporary traces (31), or are the trace systems relatively independent? Although available findings do not provide an answer to this question, there does seem to be increasing evidence that the systems are independent. Acquisition can occur, as we have seen, without permanent consolidation, and both short-term and long-term memory increase with time. All this evidence suggests (but obviously does not prove) that each experience triggers activity in each memory system. Each repeated training trial may, according to this view, potentiate short-term processes underlying acquisition while simultaneously enhancing independent underlying long-term consolidation. Obviously, acceptance of these conclusions will require additional research. If this view is substantially correct, it seems clear that any search for the engram or the basis of memory is not going to be successful. Recognition of the possibility that several independent processes may be involved at different stages of memory may help to organize the search. A careful examination of the time course of retention and memory trace consolidation, as well as examination of the bases of the effects of memory-impairing and memory-facilitating treatments, may help to guide the search. It is clear that a complete theory of memory storage must eventually provide an understanding of time-dependent processes in memory. In 1930 Lashley wrote (2), "The facts of both psychology and neurology show a degree of plasticity, of organization, and of adaptation and behavior which is far beyond any present possibility of explanation." Although this conclusion is still valid, the current surge of interest in memory storage offers hope that this conclusion may soon need to be modified.     

正确认识年龄损害记忆——动物学研究

年龄相关性学习记忆能力减退是从人到啮齿类动物的常见现象.但因受到支持的记忆系统不同,各种类型的记忆形式受到年龄影响各不相同.并非所有形式的记忆都受损.受损的记忆消失也并非同时出现,且受损程度不同,以空间性记忆受损最早最重.衰老过程中,不同形式的记忆可能此消彼长,有些形式的记忆甚至可能增强.因此,在研究年龄相关性学习记忆能力减退时最好使用多个任务进行记忆评估.     

Forgetting: trace erosion or retrieval failure?

A series of lists of random words was presented. Following each list, the subject attempted to recall the words of the list prior to the list just presented. Recall probability for a given word depended on the length of the list in which it was embedded, not on the length of the list intervening between presentation and test. These results indicate that forgetting is a failure in the memory search during retrieval rather than a degradation of the memory trace occurring between presentation and test.     

Maintenance of serological memory by polyclonal activation of human memory B cells

Production of antibodies can last for a lifetime, through mechanisms that remain poorly understood. Here, we show that human memory B lymphocytes proliferate and differentiate into plasma cells in response to polyclonal stimuli, such as bystander T cell help and CpG DNA. Furthermore, plasma cells secreting antibodies to recall antigens are produced in vivo at levels proportional to the frequency of specific memory B cells, even several years after antigenic stimulation. Although antigen boosting leads to a transient increase in specific antibody levels, ongoing polyclonal activation of memory B cells offers a means to maintain serological memory for a human lifetime.     

Discriminative control of "attention"

Three pigeons were trained to discriminate between two tones differing in frequency in the presence of light of one color (A), and not to discriminate between the tones in the presence of light of another color (B). Generalization functions that were determined in the presence of light A showed control of behavior by the frequency of the tone; those determined in the presence of light B did not.     

昆明小鼠年龄相关性物体位置再认能力减退

探讨昆明小鼠物体位置再认能力的年龄、性别效应.结果表明,10 min和24 h延迟试验中21月龄小鼠较12月龄和6月龄小鼠物体位置再认记忆有显著性减退,且主要归因于雌鼠;即刻试验中,老年雄鼠有物体位置再认即刻记忆减退.以上结果提示,老年雌性昆明小鼠有长时性和遥远性物体位置再认记忆减退.