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We analyzed a Japanese lexical database to investigate the structure of the lexical environment based on the hypothesis that the lexical environment is optimized for the functioning of verbal working memory. Our prediction was that, as a consequence of the cultural transmission of language, low‐imageable meanings tend to be represented by frequent phonological patterns in the current vocabulary rather than infrequent phonological patterns. This prediction was based on two findings of previous laboratory studies on verbal working memory. (1) The quality of phonological (phonemic and accent) representations in verbal working memory depends on phonological regularity knowledge; therefore, short‐term phonological representations are less robust for words with infrequent phonological patterns. (2) Phonological representations are underpinned by contributions from semantic knowledge; therefore, phonological representations of highly imageable words are more robust than those for low‐imageable words. Our database analyses show that nouns with less imageable meanings tend to be associated with more frequent phonological patterns in Japanese vocabulary. This lexical structure can maintain the quality of phonological representations in verbal working memory through contributions of semantic and phonological regularity knowledge. Larger semantic contributions compensate for the less robust phonological representations of infrequent phonological forms. The quality of phonological representations is preserved by phonological regularity knowledge when larger semantic contributions are not expected. [ABSTRACT FROM AUTHOR]

Aversive memories have the potential to impair one's psychological well-being. It is desirable to reduce the anguish over such memories, as well as the chance that they will be retrieved. In two experiments, we investigated whether retrieval stopping reduces the distress elicited by negative memories retrieved from cues and how the effects of retrieval stopping are modulated by mental disorders, such as depression and anxiety. Participants engaged in retrieval stopping of aversive scene memories without any diversionary thoughts (direct suppression, Experiment 1) or with diversionary positive thoughts (thought substitution, Experiment 2). Direct suppression reduced arousal elicited by the retrieval of aversive memories, while thought substitution did not only reduce arousal but also increased positive valence. Self-reported anxious/depressive symptoms negatively modulated the effects of direct suppression. For no or mild anxious/depressed individuals, direct suppression alleviated negative valence and high arousal when retrieving aversive memories. The negative relationship was not observed between the severity of the symptoms and the effect of thought substitution. These findings suggest that both retrieval stopping strategies can reduce distress from aversive memories. [ABSTRACT FROM AUTHOR]

Our daily lives are composed of several sequential actions that we perform routinely, such as making breakfast, taking a train, and changing clothes. Previous research has demonstrated that a routine system plays a role in performing and controlling repeated sequential actions in familiar situations, and a top‐down control system involves the control of the routine system in novel situations. Specifically, most developmental studies have focused on the top‐down control system (e.g., executive functions) as a factor enabling the control of goal‐directed actions in novel situations. Yet, it has not been thoroughly examined how young children learn, perform, and control repeated sequential actions in familiar contexts. In this review, based on recent computational accounts for adults, we highlight two critical aspects of the routine system from a developmental perspective: (1) automatic flexible changes of contextual representations, which enables humans to select context‐dependent actions appropriately; and (2) detection of deviant situations, which signals the need for control to avoid errors. In addition, we propose the developmental mechanism underlying the routine system and its potential driving factors such as statistical regularities and executive functions. Finally, we suggest that an investigation into the interplay between routine and executive functions can form foundations for understanding learning, performing, and controlling repeated sequential actions in young children and discuss future directions in this area. Yanaoka and Saito offer a review of developmental evidence about the routine system and its potential developmental mechanism and driving factors. They suggest that an investigation into the interplay between routine and executive functions can form foundations for understanding learning, performing, and controlling repeated sequential actions in young children. [ABSTRACT FROM AUTHOR]

This study examined whether executive functions impact how flexibly children represent task context in performing repeated sequential actions. Japanese children in Experiments 1 (N = 52; 3–6 years) and 2 (N = 50, 4–6 years) performed sequential actions repeatedly; one group received reminders. Experiment 1 indicated that reminders promote flexible changes in contextual representations. Experiment 2 observed such effects in younger children and showed executive functions were associated with the flexible representation of task context. Reminders did not perfectly compensate for the role of executive functions but wiped out individual differences in executive functions that contribute to children's acquisition of routines. Therefore, setting goals before context‐dependent actions is necessary, but not sufficient, to modulate contextual representations in routines. [ABSTRACT FROM AUTHOR]

The literature suggests that semantic similarity has a weak or null effect for immediate serial reconstruction and a facilitative effect for immediate serial recall. These observed semantic similarity effects are inconsistent with the assumptions of short-term memory (STM) models on the detrimental effect of similarity (e.g., confusion) and with observations of a robust detrimental effect of phonological similarity. Our review indicates that the experimental results are likely dependent on the manipulation strength for semantic similarity and that manipulations used in previous studies might have affected semantic assvociation as well as semantic similarity. To address these possible issues, two indices are proposed: (a) strength of manipulation on semantic similarity, gained by quantifying semantic similarity based on Osgood and associates' dimensional view of semantics, and (b) inter-item associative strength, a possible confounding factor. Our review and the results of a meta-regression analysis using these two indices suggest that semantic similarity has a detrimental effect on both serial reconstruction and serial recall, while semantic association, which is correlated with semantic similarity, contributes to an apparent facilitative effect. An effect that is not attributable to similarity or association was also implied. Review on item and order memory further suggests the facilitative effect of semantic association on item memory and the detrimental effect of the semantic similarity on order memory. Based on our findings, we propose a unified explanation of observations of semantic similarity effects for both serial reconstruction and serial recall that is in good accord with STM models. [ABSTRACT FROM AUTHOR]

Evidence supporting the idea that serial-order verbal working memory is underpinned by long-term knowledge has accumulated over more than half a century. Recent studies using natural-language statistics, artificial statistical-learning techniques, and the Hebb repetition paradigm have revealed multiple types of long-term knowledge underlying serial-order verbal working memory performance. These include (a) element-to-element association knowledge, which slowly accumulates through extensive exposure to an exemplar; (b) position–element knowledge, which is acquired through several encounters with an exemplar; and (c) whole-sequence knowledge, which is captured by the Hebb repetition paradigm and acquired rapidly with a few repetitions. Arguably, the first two are a basis for fluent and efficient language usage, and the third is a basis for vocabulary learning. Thus, statistical-learning mechanisms (and possibly episodic-learning mechanisms) may form the foundation of language acquisition and language processing, which characterize linguistic long-term knowledge for verbal working memory. [ABSTRACT FROM AUTHOR]

Working memory (WM) helps maintain information during a variety of cognitive activities in scholastic and social situations. This study focused on a social aspect of WM, specifically, how it maintains information related to people. We investigated person-based organisation of information across four experiments using the reading span task (RST). Person information (i.e., an occupational title) was provided with sentences manipulated across conditions. In Experiment 1, consistent with the assumption that person-based organisation exists in WM, participants performed better when they could easily organise target items in a person-based manner (person-based organisation) than when they were prevented from using such information. Experiments 2 and 3 investigated the process of person-based organisation using alphabetical letters as targets (unlike words in Experiment 1), which prevented possible semantic associations between person information and target items. Experiment 2 replicated Experiment 1, suggesting that contextual retrieval is critical in person-based organisation. Experiment 3 showed the person-based organisation effect even after controlling for the difficulty of the process component in the RST. The results of Experiments 2 and 3 suggest that person information could serve as contextual retrieval cues in WM. Experiment 4, which did not show the organisation effect based on information about an object (i.e., a fruit name), suggests along with Experiments 1 to 3 that the observed organisation effect in Experiments 1 to 3 was specific to person information. In addition to showing the enhanced WM performance by person-based organisation, we have suggested contextual cue-dependent retrieval as the underlying cognitive process. [ABSTRACT FROM AUTHOR]

Joint cognition refers to the mental systems that support group performance when carrying out a shared, or jointly owned task. We focused here on understanding the social configurations that underpin key phenomena in joint cognition, in particular, whether individual cognition in task-sharing environments is mostly shaped by social factors or not. To this end, we investigated, first and mainly, whether human presence is necessary for the creation of joint performance; second and separately, whether prior experience of task sharing has an adaptive influence on subsequent individual choices; and third and additionally, whether individual differences in a social trait mediate joint performance. We describe an experiment in which participants combined with another human or a computer as they attempted to generate a paired sequence that was as random as possible. First, we found little difference in joint performance with regard to whether a human or a computer was the co-participant, except for immediate repetitive response. Second, we found evidence for choice adaptation, but only under the lower time pressure. Third, we replicated previous research in which no systematic link was established between social desirability and joint performance. We conclude that joint cognition phenomena may be rooted primarily in turn-taking configurations rather than in social dynamics per se. [ABSTRACT FROM AUTHOR]

The execution of a script often requires detecting and resolving conflict with a goal, particularly in nonroutine situations. To take the example of taking a bus daily to work, if someone’s usual bus is delayed and a bus for another destination comes first, the person must inhibit taking it and wait for the usual one. Young children can gradually acquire the ability to control the execution of scripts in such nonroutine situations, but few studies have explored the control process involved. In two experiments, we investigated the role of developments in the maintenance of hierarchical goal representations and in executive functions. We measured the ability to control the execution of scripts using a task in which children helped a doll select items to wear; clothing options were presented in an unexpected order in the nonroutine situations. The younger children (4-year-olds) could not flexibly control their execution of scripts in nonroutine situations, although they could exogenously detect and resolve conflict if they were prompted to maintain a subgoal. The older children (5-year-olds) endogenously controlled script execution based on a main goal, whereas subgoal maintenance led them to rigidly control their performance. In addition, children’s inhibition abilities were associated with their control of script execution. These findings indicate that the development of the control process underlying the execution of scripts in nonroutine situations is partially dependent on the ability to maintain hierarchical goal representations. [ABSTRACT FROM AUTHOR]

Position-element association has been extensively investigated as a mechanism for serial order memory and has been widely implemented in models of short-term memory. This study examined whether and how the position-element association is learned as a form of long-term knowledge dissociated from other forms of knowledge such as sequence knowledge acquired in the Hebb list repetition paradigm. Laboratory learning experiments demonstrated that repeated exposure to a specific position-element association facilitated subsequent recall of the position-element association with experimental control of other aspects of to-be-learned statistical structure of the artificial phonotactics. The experiments also demonstrated that the positional frequency learning was more gradual than Hebb list learning, suggesting a dissociation of the two forms of learning. Functional roles of these two forms of learning were discussed. [ABSTRACT FROM AUTHOR]

Recent studies of short-term serial order memory have suggested that the maintenance of order information does not involve domain-specific processes. We carried out two dual-task experiments aimed at resolving several ambiguities in those studies. In our experiments, encoding and response of one serial reconstruction task was embedded within encoding and response of a concurrent serial reconstruction task. Order demands in both tasks were independently varied so as to find revealing patterns of interference between the two tasks. In Experiment 1, participants were to maintain and reconstruct the order of a list of verbal materials, while maintaining a list of spatial materials or vice-versa. Increasing the order demands in the outer reconstruction task resulted in small or non-reliable performance decrements in the embedded reconstruction task. Experiment 2 sought to compare these results against two same-domain baseline conditions (two verbal lists or two spatial lists). In all conditions, increasing order demands in the outer task resulted in small or non-reliable performance decrements in the embedded task. However, performance in the embedded tasks was generally lower in the same-domain baseline conditions than in the cross-domain conditions. We argue that the main effect of domain in Experiment 2 indicates the contribution of domain-specific processes to short-term serial order maintenance. In addition, we interpret the failure to find consistent cross-list interference irrespective of domain as indicating the involvement of grouping mechanisms in concurrently performed serial order tasks. [ABSTRACT FROM AUTHOR]

We report three experiments in which participants performed written serial recall of visually presented verbal sequences with items varying in visual similarity. In Experiments 1 and 2 native speakers of Japanese recalled visually presented Japanese Kanji characters. In Experiment 3, native speakers of English recalled visually presented words. In all experiments, items varied in visual similarity and were controlled for phonological similarity. For Kanji and for English, performance on lists comprising visually similar items was overall poorer than for lists of visually distinct items across all serial positions. For mixed lists in which visually similar and visually distinct items alternated through the list, a clear 'zig-zag' pattern appeared with better recall of the visually distinct items than for visually similar items. This is the first time that this zig-zag pattern has been shown for manipulations of visual similarity in serial-ordered recall. These data provide new evidence that retaining a sequence of visual codes relies on similar principles to those that govern the retention of a sequence of phonological codes. We further illustrate this by demonstrating that the data patterns can be readily simulated by at least one computational model of serial-ordered recall, the Primacy model (Page and Norris, Psychological Review, 105(4), 761-81, ). Together with previous evidence from neuropsychological studies and experimental studies with healthy adults, these results are interpreted as consistent with two domain-specific, limited-capacity, temporary memory systems for phonological material and for visual material, respectively, each of which uses similar processes that have evolved to be optimal for retention of serial order. [ABSTRACT FROM AUTHOR]

Remembering planned actions at the correct time in the future is an integral component of prospective cognition. Recent studies on future remembering have led to suggestions that prospective cognition might be based on past experience. To test this hypothesis, we focused on retrieval-induced forgetting (RIF), which usually indicates that remembering past events suppresses memory for related but different past events. The current study assessed RIF in two kinds of event-based prospective memory (PM) tasks using either focal or non-focal cues for ongoing tasks. Participants studied six members from each of eight taxonomic categories and then practiced recalling three of the six members from four of the eight categories using category-stem cues. This retrieval practice suppressed the detection of non-practiced members of the practiced categories during the PM task with non-focal cues (Experiment 1) but not with focal cues (Experiment 2). The results suggest that recall of certain items inhibits the function of the others as PM cues, but only if the PM task does not largely share its processing with the ongoing task. [ABSTRACT FROM AUTHOR]

According to the multicomponent view of working memory, both auditory-nonverbal information and auditory-verbal information are stored in a phonological code and are maintained by an articulation-based rehearsal mechanism (Baddeley, 2012). Two experiments have been carried out to investigate this hypothesis using sound materials that are difficult to label verbally and difficult to articulate. Participants were required to maintain 2 to 4 sounds differing in timbre over a delay of up to 12 seconds while performing different secondary tasks. While there was no convincing evidence for articulatory rehearsal as a main maintenance mechanism for auditory-nonverbal information, the results suggest that processes similar or identical to auditory imagery might contribute to maintenance. We discuss the implications of these results for multicomponent models of working memory. [ABSTRACT FROM AUTHOR]

Highlights: [•] A speech-error induction technique revealed principles of serial order control. [•] The technique successfully induced within-word adjacent mora exchanges in Japanese. [•] The exchange errors indicate the temporal distance principle within a word. [•] Induced speech errors exhibited serial position effects. [•] The serial position effects indicate the edge principle within a word. [ABSTRACT FROM AUTHOR]

Abstract: We have shown in [1] that the invariant varieties of periodic points (IVPP) of all periods of some higher dimensional rational maps can be derived, iteratively, from the singularity confinement (SC). We generalize this algorithm, in this paper, to apply to any birational map, which has more invariants than the half of the dimension. [Copyright &y& Elsevier]

Caplan and colleagues have recently explained paired-associate learning and serial-order learning with a single-mechanism computational model by assuming differential degrees of isolation. Specifically, two items in a pair can be grouped together and associated to positional codes that are somewhat isolated from the rest of the items. In contrast, the degree of isolation among the studied items is lower in serial-order learning. One of the key predictions drawn from this theory is that any variables that help chunking of two adjacent items into a group should be beneficial to paired-associate learning, more than serial-order learning. To test this idea, the role of visual representations in memory for spoken verbal materials (i.e., imagery) was compared between two types of learning directly. Experiment 1 showed stronger effects of word concreteness and of concurrent presentation of irrelevant visual stimuli (dynamic visual noise: DVN) in paired-associate memory than in serial-order memory, consistent with the prediction. Experiment 2 revealed that the irrelevant visual stimuli effect was boosted when the participants had to actively maintain the information within working memory, rather than feed it to long-term memory for subsequent recall, due to cue overloading. This indicates that the sensory input from irrelevant visual stimuli can reach and affect visual representations of verbal items within working memory, and that this disruption can be attenuated when the information within working memory can be efficiently supported by long-term memory for subsequent recall. [ABSTRACT FROM AUTHOR]

Theory of mind (ToM) refers to the ability to reason about the mental states of others. An increasing number of studies have revealed that working memory (WM) plays an important role in ToM. The present study applied WM loads to adults during a ToM task in order to investigate the impact on mental-state reasoning performance. The task required participants to estimate the probabilities of several possible behaviours for a protagonist following the presentation of a ToM story. Participants were also required to maintain a meaningless two- (light WM load) or seven-letter English alphabet string (heavy WM load) during story comprehension and mental-state reasoning. The results show that the combination of light WM load applied during story comprehension with heavy WM load during mental-state reasoning results in an overestimation of the probability that the protagonist's behaviour will accord with a participant's knowledge. Conversely, a heavy WM load applied during story comprehension, regardless of the type of WM load during mental-state reasoning, did not result in this probability estimation bias. We discuss these findings from the perspective of a WM representation account. [ABSTRACT FROM AUTHOR]

Recent studies have revealed that verbal representations play an important role in various task-switching situations. This study examined whether verbal representations contribute to the actual switching process using random task cueing with two cues per task. This procedure allowed us to produce a trial in which the cue switched, but the task repeated, thereby separating the cue-switching process from the actual task-switching process. Participants performed colour or shape judgements that were initiated by an arbitrary symbol cue (Experiments 1 and 2) or a kanji cue (Experiment 3) under control, articulatory-suppression, and foot-tapping conditions. In Experiments 1 and 2 with the arbitrary cues, articulatory suppression impaired performance in only the cue-switch condition. In Experiment 3, in which a kanji cue indicated the upcoming task name, articulatory suppression did not have any effects. These results suggest that the involvement of verbal representations in random task cueing is based on the cue-switching process rather than on the task-switching process. [ABSTRACT FROM AUTHOR]

Abstract: Although an increasing number of studies on adults have indicated that working memory (WM) contributes to the ability to understand the mental states of others (i.e., theory of mind), the detailed mechanism by which WM contributes to successful reasoning has not previously been revealed. This study shows that WM modulates the degree of attribution of one''s own knowledge to others'' mental states. Participants were asked to read a story twice (Experiment 2) or as carefully as possible (Experiment 3) and to estimate the probability percentages of possible choices for a naive protagonist''s behavior. The participants were then asked to maintain either a two- or seven-letter alphabet string (i.e., a light or heavy WM load, respectively) during the probability estimation but not during the story comprehension. The results showed that compared to the participants with a light WM load, those with a heavy WM load estimated a significantly higher probability of the choice indicating that the protagonist would behave on the basis of a fact that the participants knew but the protagonist did not. This result indicates that WM moderates the extent to which adults attribute their own knowledge to others'' mental states. The role of WM in theory of mind and in heuristic strategy for making probability judgments was then discussed. [Copyright &y& Elsevier]

Summary: Traditional neurological models of language were based on a single neural pathway (the dorsal pathway underpinned by the arcuate fasciculus). Contemporary neuroscience indicates that anterior temporal regions and the “ventral” language pathway also make a significant contribution, yet there is no computationally-implemented model of the dual pathway, nor any synthesis of normal and aphasic behavior. The “Lichtheim 2” model was implemented by developing a new variety of computational model which reproduces and explains normal and patient data but also incorporates neuroanatomical information into its architecture. By bridging the “mind-brain” gap in this way, the resultant “neurocomputational” model provides a unique opportunity to explore the relationship between lesion location and behavioral deficits, and to provide a platform for simulating functional neuroimaging data. [Copyright &y& Elsevier]

This study investigated how prosodic aspects and wordlikeness of nonwords affect young Japanese children's repetition of nonwords. We contrasted two conditions in which a nonword comprised of two morae was pronounced with and without a small pause between the two morae. We also manipulated accent patterns of presentation of nonwords. The results indicated that the presence of a small pause in a nonword had a facilitating effect on the repetition of nonwords. The advantage of high-wordlike sequences over low-wordlike sequences was observed only when the sequence was presented without a pause. In contrast, the effect of accent patterns of presentation interacted with vocabulary sizes of children. These results were interpreted in terms of the framework of phonological working memory and the segmentation of the spoken Japanese language. [ABSTRACT FROM AUTHOR]

By studying higher dimensional rational maps, we have shown, in our previous papers, that periodic points of integrable maps with sufficient number of invariants form invariant varieties of periodic points (IVPPs) different for each period. In this paper, we study the transition of a nonintegrable map to an integrable one. In particular, we investigate analytically where the Julia set goes and how it disappears when the map becomes integrable. We show that the behavior of the Julia set is different, depending on whether the map has an unstable variety of fixed point (UVFP), which becomes nonfixed in the integrable limit. If the map does not have an UVFP, all periodic points approach IVPP or fixed points of the integrable map. Otherwise, a large part of periodic points of all periods approach the UVFP and the UVFP itself becomes a variety of indeterminate points unless it disappears from the map. Moreover, we show that a map recovered by the singularity confinement generates the sequence of all IVPPs. [ABSTRACT FROM AUTHOR]

This essay considers the intricate connection between detective fiction and the novel in the latter half of the 1880s through an examination of Tsubouchi Shōyō's literary project. A central figure in the articulation of the notion of the modern novel, Shōyō was also one of the first Japanese authors to experiment with detective fiction, translating Anna Katharine Green's XYZ as Nisegane tsukai in 1887. By reading his theoretical and fictional works in conjunction with this translation, I argue that the detective fiction genre played a critical role in legitimating the inherent contradiction in Shōyō's theory of the modern novel between its promotion of the moral author and the unethical potential of his mission. [ABSTRACT FROM AUTHOR]

Recent task-switching studies in which a predictable task sequence has been used have indicated that verbal representation contributes to the control of task order information. The present study focused on the role of verbal representation in sequential task decisions, which are an important part of task order control, and examined the effects of articulatory suppression in a random-task-cuing paradigm with two different types of cues presented just before the presentation of a stimulus: a transition cue and a task cue. The former cue provided information only about switching or repeating the task, whereas the latter was associated directly with the identity of the task (i.e., indicating a parity or a magnitude task). In Experiment 1, in which transition cues guided task sequences, articulatory suppression impaired performance in both repetition and switch trials, thereby increasing the mixing costs. In Experiment 2, in which a task cue, rather than a transition cue, was presented to examine the influence of a cue-decoding process, articulatory suppression had no specific effect on task performance. Experiment 3, in which the transition cue and the task cue were randomly presented in the same block to equalize the memory load and task strategy for the two types of cues, confirmed that articulatory suppression significantly increased the mixing costs only in transition cue trials. The results from the three experiments indicated that the use of verbal representation is effective in sequential task decision-that is, in selecting a task set on the basis of transient task order information in both repetition and switch trials. [ABSTRACT FROM AUTHOR]

The Epstein-Barr virus (EBV), a human B-lymphotropic gamma herpesvirus, contains multiple repetitive sequences within its genome. A group of repetitive sequences, known as the family of repeats (FR), contains multiple binding sites for the viral trans-acting protein EBNA-1. The FR sequences are important for viral genome maintenance and for the regulation of the promoter involved in viral latent gene expression. It has been reported that a palindromic sequence with a putative secondary structure exists at the 3' end of the FR in the genome of the EBV B95-8 strain and that this palindromic sequence has been deleted from the FR of the commonly used EBV miniplasmids. For the first time, we cloned an EBV B95-8 DNA fragment containing the full-length FR, which enabled us to examine the functional difference between full-length and deleted FRs. The full-length FR, like the deleted FR, functioned as a transcriptional enhancer of the viral latent gene promoter, but that transactivation was significantly attenuated in the case of the full-length FR. No significant enhancement of replication was observed when the deleted FR was replaced with the full-length FR in an EBV miniplasmid. By contrast, when the same set of FR sequences were tested in the context of the complete EBV genome, the full-length FR resulted in more-efficient B-cell transformation than the deleted FR. We propose that the presence of the full-length FR contributes to the precise regulation of the viral latent promoter and increases the efficiency of B-cell transformation. [ABSTRACT FROM AUTHOR]

In working memory (WM) span tests participants have to maintain to-be-remembered information while processing other, potentially distracting, information. Previous studies have shown that WM span scores are greater when span lists start with a long processing task and end with a short processing task than when these processing tasks are presented in the reverse order (e.g., Towse, Hitch, & Hutton, 2000). In Experiment 1, we obtained a similar stimulus order effect in a reasoning span test, using reasoning sentences that were equated for length in terms of the number of constituent words, but which differed in processing complexity; span scores were greater when lists began with a complex sentence and ended with a simple sentence than when this stimulus order was reversed. In Experiment 2, the stimulus order effect was not found when processing duration was held constant while sentence complexity was varied using a computer-paced moving window presentation paradigm. These results suggest that duration-based constraints can affect degree of forgetting independently of the load generated during processing phases in WM span performance and therefore imply that time-related forgetting can occur in WM span tests, particularly when the difficulty of the processing component blocks active maintenance of to-be-remembered material. [ABSTRACT FROM AUTHOR]

Aim: Hepatocellular carcinoma (HCC) is one of the most commonly occurring malignances worldwide. Curative therapies such as resection, percutaneous ethanol injection (PEI) and radiofrequency ablation (RFA) have been applied to patients with early-stage HCC. Patients with more advanced cancers require local or systemic therapies. We present the results of our retrospective review conducted to evaluate whether transarterial chemoembolization (TACE) alone and combined TACE with percutaneous ablation for HCC exhibited superior efficacy to palliative treatment. Methods: The effects of TACE and of the combined therapies (TACE + PEI or TACE + RFA) on the long-term survival rates were evaluated in 268 untreated HCC patients by various statistical analyses. Results: The cumulative survival rates in the TACE alone group were significantly superior to those in the palliative treatment group. Further, the cumulative survival rates in the combined TACE + PEI/RFA group were significantly superior to those in the TACE alone group. When the comparison among the groups was restricted to patients with two or three tumors fulfilling the Milan criteria, significantly greater prolongation of survival was observed in the combined TACE + PEI/RFA group than in the PEI/RFA alone group. Conclusions: The aforementioned treatment modalities yielded greater improvements of the survival rate and survival duration as compared to palliative treatment in HCC patients. Furthermore, in terms of the effect on the survival period, combined TACE + PEI/RFA therapy was more effective than TACE monotherapy, and also more effective than PEI or RFA monotherapy in cases with multiple tumors fulfilling the Milan criteria. [ABSTRACT FROM AUTHOR]

Background: Spontaneous rupture is rare complication of hepatocellular carcinoma (HCC) with high mortality rate in cirrhotic cases. The aim of this study was to determine the factors influencing prognosis in cases of spontaneously ruptured HCC and to investigate the outcomes of the treatments employed, especially transcatheter arterial embolization (TAE). Methods: A retrospective multicenter study was conducted in 48 cirrhotic patients with spontaneous rupture of HCC. Conservative treatment was employed in 32 patients (ConT group) and TAE was performed in 16 patients (TAE group). Results: The median survival time (MST) in the ConT group was only 13.1 days and the survival rate was extremely poor: 59.4% at 7 days, 37.5% at 14 days, and 6.3% at 30 days. On the other hand, the MST in the TAE group was 244.8 days and the survival rate was 87.5% at 1 month, 56.3% at 3 months, 23.4% at 12 months, and 15.6% at 24 months. According to the results of univariate analyses, factors associated with poor hepatic function and poor suitability for TAE was important determinants of short-term death (less than 3 weeks) among the patients (p < 0.05). On the other hand, among the patients in whom initial TAE was successfully performed (n = 15), a multivariate analysis showed that a maximum tumor size not exceeding 7 cm was the only independent factor determining long-term survival (p = 0.0130). Conclusion: Despite the inherent limitations of this retrospective study, TAE appears to be a useful treatment strategy for cirrhotic patients with spontaneous HCC rupture, as it yielded a longer survival period compared with conservative treatment in patients with ruptured HCC. Among the patients with ruptured HCC in whom initial TAE was successfully performed, the maximum tumor size was an important factor influencing survival. [ABSTRACT FROM AUTHOR]

Abstract: In a series of three experiments, native speakers of Japanese performed serial ordered written recall of visually presented Japanese kanji characters that varied systematically in visual and phonological similarity. Overall effects of phonological similarity were observed for retention of serial order under silent reading in Experiments 1 and 3 and they disappeared in articulatory suppression conditions in Experiments 2 and 3. All three experiments showed main effects of visual similarity even in articulatory suppression conditions in Experiments 2 and 3. This indicated spontaneous use of visual codes in immediate serial recall. It is suggested that any models of serial order memory should incorporate domain specificity. [Copyright &y& Elsevier]

The present study examined whether articulatory suppression influences homophone effects in semantic access tasks using Japanese kanji words. In Experiment 1, participants were required to decide whether visually presented word pairs were synonyms. This experiment replicated the homophone effect observed in previous research that showed more false positive errors in response to nonsynonym homophone pairs than to controls. The present study found that this homophone effect was also obtained under an articulatory suppression condition. In Experiment 2, participants performed a semantic decision task, in which they had to judge whether a visually presented target word was an exemplar of a definition that was shown immediately before presentation of the target word. The homophone effect observed in previous studies was replicated - that is, longer response times and more false positive errors were associated with homophones of correct exemplars than with nonhomophone control words. This homophone effect was also obtained under an articulatory suppression conditions. These results suggest that the phonological processing that produces the homophone effects in semantic access tasks using Japanese kanji words does not include articulatory mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: In working memory (WM) span tests, participants maintain memory items while performing processing tasks. In this study, we examined the impact of task processing requirements on memory-storage activities, looking at the stimulus order effect and the impact of storage requirements on processing activities, testing the processing time effect in WM span tests. The stimulus order effect is a phenomenon whereby span scores are higher when span lists end with a shorter task than when they end with a longer task. The processing time effect refers to the phenomenon whereby the processing speed slows for the later processing positions in a list in WM span tests when participants have more memory items to remember. Two experiments demonstrated the domain-specific nature of the stimulus order effect, which was observed only when the processing and storage materials were in the same domain (either verbal or visuospatial domains), and the domain-general nature of the processing time effect, which was observed with any combination of processing and storage materials. Although the domain specificity of the stimulus order effect is compatible with the representation-based interference view proposed by Saito and Miyake [Saito, S., & Miyake, A. (2004). On the nature of forgetting and the processing-storage relationship in reading span performance. Journal of Memory and Language, 50, 425–443.], the domain generality of the processing time effect is inconsistent with their account and indicates the involvement of a central bottleneck in WM span performance. [Copyright &y& Elsevier]

We conducted three experiments using a list paradigm to examine how articulatory suppression and response–stimulus interval (RSI) manipulation affected task switching. Experiments 1 and 2 tested task-switching performance under a short and long RSI and three concurrent task conditions (control, articulatory suppression, and tapping) without external task cues. The results indicated that alternation had a greater effect under articulatory suppression than under the control and tapping conditions, and that articulatory suppression costs were unrelated to the RSI. In Experiment 3, an external task cue was provided with each stimulus, and the negative effect of articulatory suppression on alternation cost was eliminated. These results indicated that articulatory suppression effects did not differ between conditions of short and long RSI and that the availability of verbal representations of task information was independent of RSI length. This paper discussed the possible roles played by the phonological loop in task-switching paradigms. [ABSTRACT FROM AUTHOR]

Abstract: This study investigated the effects of association values and the influences of prosodic information on Japanese children''s repetition of nonwords with varying association values and with or without pitch accent. Fifteen 3- and 4-year-olds (mean age=4.42 years, range: 3.9–4.9) and nineteen 5- and 6-year-olds (mean age=5.71 years, range: 5.1–6.1) participated in this experiment. Concerning the nonword repetition scores, an effect of association value was found only in older children for consonants of nonwords only, whereas the effect of accent pattern was observed only in young children for both consonants and vowels of nonwords. The occurrences of both effects were connected to differences in the ages of the children and the types of phoneme in nonwords. We interpret these results in the context of the framework of phonological working memory. [Copyright &y& Elsevier]

A general scheme to find string boundary states is developed within the framework of the theory of KP hierarchy. The method is applied to calculate correlation function of intersecting D-branes and rederived from the results of our previous works as special examples. A matrix generalization of this scheme provides a method to study dynamics of coincident multi D-branes. [ABSTRACT FROM AUTHOR]

We describe the Sato–Wilson type formulation of the KP hierarchy within the framework of closed string theory. A matrix generalization of this formalism is shown to allow natural interpretation of coincident D-branes as a sourse of non-Abelian gauge theory. [ABSTRACT FROM AUTHOR]

The hepatitis C virus (HCV) is a major cause of liver disease worldwide. The understanding of the viral life cycle has been hampered by the lack of a satisfactory cell culture system. The development of the HCV replicon system has been a major advance, but the system does not produce virions. In this study, we constructed an infectious HCV genotype lb cDNA between two ribozymes that are designed to generate the exact 5' and 3' ends of HG!. A second construct with a mutation in the active site of the viral RNA-dependent RNA polymerase (RdRp) was generated as a control. The HCV-ribozyme expression construct was transfected into Huh7 cells. Both HCV structural and nonstructural proteins were detected by immunofluorescence and Western blot. RNase protection assays showed positive- and negative-strand HCV RNA. Sequence analysis of the 5' and 3' ends provided further evidence of viral replication. Sucrose density gradient centrifugation of the culture medium revealed colocalization of HCV RNA and structural proteins in a fraction with the density of 1.16 g/ml, the putative density of HCV virions. Electron microscopy showed viral particles of &ap;50 nm in diameter. The level of HCV RNA in the culture medium was as high as 10 million copies per milliliter. The HCVeribozyme construct with the inactivating mutation in the RdRp did not show evidence of viral replication, assembly, and release. This system supports the production and secretion of high-level HCV virions and extends the repertoire of tools available for the study of HCV biology. [ABSTRACT FROM AUTHOR]

Earlier research has demonstrated that collaborative groups recall more than individuals, but less than nominal groups (pooled performance of individuals), thus exhibiting collaborative inhibition. In two experiments, all participants were first asked to recall story material on their own. Some participants were then assigned to pairs and recalled the material collaboratively. On the other hand, the participants in the individual recall condition were asked to recall the material once again on their own. In Experiment 1, the collaborative pairs recalled less than the nominal pairs in accordance with previous studies. In Experiment 2, the timing of the initial individual recall was manipulated by inserting one week between the learning and the recall. The collaborative inhibition was eliminated in this situation. Sources of the collaborative inhibition in immediate recall and its disappearance in delayed recall are discussed in terms of the effect of cross cueing in collaborative remembering. [ABSTRACT FROM AUTHOR]

To explore the relationship between short-term memory and speech production, we developed a speech error induction technique. The technique, which was adapted from a Japanese word game, exposed participants to an auditory distractor word immediately before the utterance of a target word. In Experiment 1, the distractor words that were phonologically similar to the target word led to a greater number of errors in speaking the target than did the dissimilar distractor words. Furthermore, the speech error scores were significantly correlated with memory span scores. In Experiment 2, memory span scores were again correlated with the rate of the speech errors that were induced from the task-irrelevant speech sounds. Experiment 3 showed a strong irrelevant-sound effect in the serial recall of nonwords. The magnitude of the irrelevant-sound effects was not affected by phonological similarity between the to-be-remembered nonwords and the irrelevant-sound materials. Analysis of recall errors in Experiment 3 also suggested that there were no essential differences in recall error patterns between the dissimilar and similar irrelevant-sound conditions. Weproposed two different underlying mechanisms in immediate memory, one operating via the phonological short-term memory store and the other via the processes underpinning speech production. [ABSTRACT FROM AUTHOR]

Four experiments examined the nature of forgetting and the processing–storage relationship during performance on a prevalent working memory task, the reading span test. Using two different presentation paradigms, Experiments 1 and 2 replicated finding that the Short-Final lists, which presented a long sentence first and a short sentence last, led to better recall performance than the reverse-order Long-Final lists. This effect was still obtained when the retention duration for the target words was held constant and the amount of sentence processing required during that interval was varied (Experiment 3). However, the effect disappeared when the retention duration was varied while holding constant the amount of sentence processing required (Experiment 4). These results suggest that the amount of processing activities, not the sheer passage of time, may be the critical factor underlying the sentence order effect, thereby challenging purely time-based explanations of forgetting during reading span performance. In addition, the analysis of reading times (Experiment 1) revealed that the number of memory items had a subtle yet reliable negative effect on reading times, suggesting that the processing and storage requirements of the reading span test are not completely independent. [Copyright &y& Elsevier]

In a series of experiments, we examine some effects of articulatory suppression in task switching. The results from Experiments 1a and 2a showed that switch costs in the articulatory suppression condition were larger than those in the control and tapping conditions when the switching cues were not provided. On the other hand, articulatory suppression did not have any effect on switch costs in Experiments 1b and 2b, where the switching cues were provided. In Experiment 3, using a computer-assisted experimentation, this pattern of data was replicated in a two-factor design with articulatory suppression and switching cues factors. The results indicate that a specific component in working memory, the phonological loop, might contribute to the performance in task switching, at least in situations where the external task cues were not available. The data reported here suggest that the phonological loop plays an important role in one of the executive control processes, and challenge the traditional idea that the slave systems are simply governed by the central executive in the working memory. [ABSTRACT FROM AUTHOR]

We study hyperelliptic Nambu flows associated with some n dimensional maps and show that discrete integrable systems can be reproduced as flows of this class. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The purpose of the current study was to examine the relationship between short-term memory for rhythm and the phonological loop in working memory. Results showed that digit span scores significantly correlated with the scores on the rhythmic memory task, and that the correlation between the two scores remained significant even after the common variance with reading speed was partialled out. Partial correlation and regression analyses indicated that the relation between memory for rhythm and digit span scores is mediated by the third component in the phonological loop, the component that is responsible for regulation of timing mechanisms in immediate memory tasks. [ABSTRACT FROM AUTHOR]

Examines the expression of apoptosis in rat liver by hepatic vagus hyperactivity following ventromedial hypothalamus (VMH) lesioning. Role of Fas ligand system in apoptosis; Impact of VMH lesions on Fas messenger RNA and protein expression; Transition in the region of strongest Fas expression; Analysis of protease activation.

Studies the expression of apoptosis on rat liver by hepatic vagus hyperactivity after ventromedial hypothalamic (VMH) lesioning. Measurement of caspase 3-like proteases in hepatocytes, Kupffer cells, and sinusoidal endothelial cells; Effect of VMH lesions on total body weight and liver weight.

Presents information on a study which examined whether the Fas/Fas ligand system mediates apoptosis in rats with ventromedial hypothalamus (VMH) lesions. Materials and methods; Effects of VMH lesions on total body weight and liver weight; Expression of Fas and Fas ligand protein in liver after VMH lesioning.

Abstract Background: Vascular endothelial growth factor (VEGF) exerts its actions on the microvasculature, by interacting with specific endothelial cell receptors, and thus, contributes to angiogenesis and growth in many tumours. Methods: Using nested reverse-transcription–polymerase chain reaction, we examined the biopsy specimens of 14 patients with human hepatocellular carcinoma (HCC) and cirrhosis, for the expression of hepatic VEGF, and the VEGF receptors KDR and flt-1. To avoid the influence of hypoxia or ischaemia induced by surgical manipulation, we used biopsy specimens of the liver instead of resected specimens. Results: Vascular endothelial growth factor mRNA expression was detected in the tumour portion of the specimens in 13 of 14 patients (93%), and in the corresponding non-tumour portion of the specimens in eight patients (57%; P = 0.08). No differences were found between the tumour portion and the corresponding non-tumour portion in relative concentrations of VEGF mRNA. However, mRNA expression of the VEGF receptors, KDR and flt-1, was detected in 14 (100%) and 11 (79%) of the tumour portions, respectively, and in four (29%) and five (36%) of the corresponding non-tumour portions, respectively (χ test: KDR, P < 0.01; flt-1, P = 0.08). The relative concentration of KDR mRNA in the tumour portions was significantly higher than in the non-tumour portions (Mann–Whitney U-test: P < 0.001) but no differences were detected for flt-1. Conclusions: KDR mRNA is significantly overexpressed in HCC lesions and could be associated with the angiogenesis and tumour growth induced by VEGF. [ABSTRACT FROM AUTHOR]

The interaction of Fas (APO-1/CD95) and the Fas ligand system induces apoptosis. However, the role of the Fas/Fas ligand system in normal physiological liver cell death remains to be determined. Using northern blotting analysis, we investigated the role of Fas and Fas ligand mRNA expression in liver regeneration in rats until 14 days after partial hepatectomy. Partial hepatectomy led to a significant decrease in Fas mRNA levels at 2 h, with a further gradual reduction until 18 h. The minimum Fas mRNA levels persisted until 5 days after the surgery. Fas mRNA levels then increased markedly at 6 days, and gradually increased to the initial levels by 14 days after the surgery. However, partial hepatectomy did not affect the expression of Fas ligand mRNA levels. These findings suggest that Fas mRNA is down-regulated in liver regeneration after partial hepatectomy, and that when the original liver mass is gradually regenerating, Fas mRNA is again up-regulated to the initial levels. [ABSTRACT FROM AUTHOR]

Children engage cognitive control reactively when they encounter conflicts; however, they can also resolve conflicts proactively. Recent studies have begun to clarify the mechanisms that support the use of proactive control in children; nonetheless, sufficient knowledge has not been accumulated regarding these mechanisms. Using behavioral and pupillometric measures, we tested the novel possibility that 5‐year‐old children (N = 58) learn to use proactive control via the acquisition of abstract task knowledge that captures regularities of the task. Participants were assigned to either a proactive training group or a control training group. In the proactive training group, participants engaged in a training phase where using proactive control was encouraged, followed by a test phase using different stimuli where both proactive and reactive control could be used. In the control training group, participants engaged in a training phase where both cognitive control strategies could be used, followed by a similarly‐structured test phase using different stimuli. We demonstrated children in the control training group responded more quickly and accurately and showed greater cue‐related pupil dilation in the test phase than in the training phase. However, there were no differences in response times, accuracies, and pupil dilation between the proactive and control training groups in the training and test phases. These findings suggest that prior task experience, that goes beyond specific knowledge about the timing of task goal activation, can lead children to engage more proactive control endogenously, even if they are not directly encouraged to do so. [ABSTRACT FROM AUTHOR]

Cognitive control is a hallmark of human cognition. A large number of studies have focused on the plasticity of cognitive control and examined how repeated task experience leads to the improvement of cognitive control in novel task environments. However, it has been demonstrated that training-induced changes are very selective and that transfer occurs within one task paradigm but not across different task paradigms. The current study tested the possibility that cross-paradigm transfer would occur if a common cognitive control strategy is employed across different task paradigms. Specifically, we examined whether prior experience of using reactive control in one task paradigm (i.e., either the cued task-switching paradigm or the AX-CPT) makes adults (N = 137) and 9- to 10-year-olds (N = 126) respond in a reactive way in a subsequent condition of another task paradigm in which proactive control could have been engaged. Bayesian generalized mixed-effects models revealed clear evidence of an absence of cross-paradigm transfer of reactive control in both adults and school-aged children. Based on these findings, we discuss to what extent learned control could be transferred across different task contexts and the task-specificity of proactive/reactive control strategies. [ABSTRACT FROM AUTHOR]