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Network analyses of the phonological mental lexicon show that words are clustered into communities and phonologically dissimilar words can be connected to each other through distant paths. Here we investigate whether behavioral traces of the large-scale structure of the phonological lexicon can be obtained. Participants listened to pairs of spoken words and made phonological similarity judgments for word pairs with varying path lengths and community membership. Path length in the phonological network represented the number of steps needed to traverse from one word to another word in the phonological network. Word pairs were either from the same phonological community or from different communities. Results indicated that participants were sensitive to large-scale structure of the phonological lexicon. Word pairs residing in the same community were more likely rated as similar sounding than word pairs from different communities. Word pairs with longer path lengths were less likely rated as similar sounding than word pairs with shorter path lengths. Computational simulations suggested that the behavioral findings could be accounted for via a spreading activation mechanism implemented on the phonological network. Taken together, our results provide converging evidence that people are sensitive to the large-scale structure of the phonological language network and have implications for our understanding of the nature of phonological similarity representations in the mental lexicon. [ABSTRACT FROM AUTHOR]

Human memory is known to be supported by sleep. However, less is known about the effect of sleep on false memory, where people incorrectly remember events that never occurred. In the laboratory, false memories are often induced via the Deese-Roediger-McDermott (DRM) paradigm where participants are presented with wordlists comprising semantically related words such as nurse, hospital and sick (studied words). Subsequently, participants are likely to falsely remember that a related lure word such as doctor was presented. Multiple studies have examined whether these false memories are influenced by sleep, with contradictory results. A recent meta-analysis suggests that sleep may increase DRM false memory when short lists are used. We tested this in a registered report (N = 488) with a 2 (Interval: Immediate versus 12 h delay) × 2 (Test Time: 9:00 versus 21:00) between-participant DRM experiment, using short DRM lists (N = 8 words/list) and free recall as the memory test. We found an unexpected time-of-day effect such that completing free recall in the evening led to more intrusions (neither studied nor lure words). Above and beyond this time-of-day effect, the Sleep participants produced fewer intrusions than their Wake counterparts. When this was statistically controlled for, the Sleep participants falsely produced more critical lures. They also correctly recalled more studied words (regardless of intrusions). Exploratory analysis showed that these findings cannot be attributed to differences in output bias, as indexed by the number of total responses. Our overall results cannot be fully captured by existing sleep-specific theories of false memory, but help to define the role of sleep in two more general theories (Fuzzy-Trace and Activation/Monitoring theories) and suggest that sleep may benefit gist abstraction/spreading activation on one hand and memory suppression/source monitoring on the other.

The associative manner by which thoughts follow one another has intrigued scholars for decades. The process by which an association is generated in response to a cue can be explained by classic models of semantic processing through distinct computational mechanisms. Distributed attractor networks implement rich-get-richer dynamics and assume that stronger associations can be reached with fewer steps. Conversely, spreading activation models assume that a cue distributes its activation, in parallel, to all associations at a constant rate. Despite these models' huge influence, their intractability together with the unconstrained nature of free association have restricted their few previous uses to qualitative predictions. To test these computational mechanisms quantitatively, we conceptualize free association as the product of internal evidence accumulation and generate predictions concerning the speed and strength of people's associations. To this end, we first develop a novel approach to mapping the personalized space of words from which an individual chooses an association to a given cue. We then use state-of-the-art evidence accumulation models to demonstrate the function of rich-get-richer dynamics on the one hand and of stochasticity in the rate of spreading activation on the other hand, in preventing an exceedingly slow resolution of the competition among myriad potential associations. Furthermore, whereas our results uniformly indicate that stronger associations require less evidence, only in combination with rich-get-richer dynamics does this explain why weak associations are slow yet prevalent. We discuss implications for models of semantic processing and evidence accumulation and offer recommendations for practical applications and individual-differences research. [ABSTRACT FROM AUTHOR]

The serial‐order effect wherein originality increases over time is one of the most robust findings in modern psychology. This effect, found in either individual or group sessions, is based on associative and spreading activation mechanisms: Mental association takes place in temporal sequential order from commonly (closely) to unusually (distantly) related semantic concepts stored in long‐term memory. Thus, data from previous studies might suggest that, in collective problem‐solving, we endure long meetings and pay closer attention to ideas presented toward the end of the meeting. However, members in innovative organizations have been reported to typically generate ideas on their own before group brainstorming. We hypothesized that in the subsequent group brainstorming session members would state their most appealing ideas first due to impression management. Our results from the individual‐then‐group hybrid brainstorming paradigm show that idea quality during the group session peaks early and then decays, in terms of both the number of high‐quality ideas produced and the proportion of ideas that are high‐quality. This "reverse" serial‐order effect implies that meeting for a reasonably brief time and looking into ideas shared early during the meeting may lead to better decisions—if individuals generated ideas prior to the meeting. We also found that flexibility (the rate at which new idea categories were introduced) dropped rapidly, but at a certain point of time, it stopped decreasing. This potentially suggests that extended group interaction after individual idea generation could bring greater idea diversity rather than higher overall quality. In addition, we found that the updated, cognitively constrained organizational norm for brainstorming, which likely narrows the scope of search, led to greater idea quantity (fluency), quality, and flexibility than the traditional, unconstrained norm. Our work challenges the traditional application of spreading activation theory to interpersonal, group, or organizational settings and calls for attention to the specific communicative processes of problem‐solving and decision‐making in question. [ABSTRACT FROM AUTHOR]

Retrieval-induced forgetting (RIF) is a paradigm where re-peated study and cue-based retrieval of words impair retrievalof related, but unstudied, words. We present a process model,situated in the ACT-R/E cognitive architecture, that accountsfor the RIF task using the architecture’s overarching theory ofassociative learning. In this theory, studying words strengthenstheir association with their related cues; this, in turn, weakensthe association between those cues and any other words theyare related to. We show this account fits a recent dataset thatexplores cueing in the RIF task (Perfect et al., 2004).

A spreading activation trajectory ciphering method inspired by the spreading activation theory in psychology field is proposed. Using the plain text as the activation source, a spreading activation trajectory is generated as cipher text by two actions which are called spread and activation. The spreading operation finds a point suit for the representation of a character near the previous point. The activation operation finds the position of next point. The activation operation can improve the utilization of cipher space to gain low mutual information and coefficient. The method is simple and flexible. It consumes almost no more time when its key becomes much longer. As a result, it is almost immune to brutal enumerating attacks. Low mutual information and low coefficients between plaintext and cipher text can prevent the method from statistical attack. [ABSTRACT FROM AUTHOR]

A well agreed discourse in music perception research is that affective response can be generated by music when a tendency in the music is delayed or inhibited. There is a consensus that this tendency is statistically driven, derived from exposure to culturally situated musical idioms. By presenting a neural-network inspired spreading activation model (SAM) this paper argues that the nature of the tendency is worthy of further investigation. SAM organises the music stream perceived by the listener continuously into segments such that a match with an existing ‘mental representation’ (node) is found, which is then linked to the node for the previously segmented part of the music stream, with the link between these nodes strengthening and consolidating with exposure. The currently activated segment (the music being sounded) will prime the best matching (strongest linked) node available, generating expectancy. Expectancy is defined as the most strongly primed segment, and emerges dynamically through experience with environmental and musical contexts, rather than schematic or prototypical means. Expectancy is the specific exemplar instance that the activated (currently sounding) segment of music and contextual factors prime. This hypothesis of veridical dominance has implications for enduring aspects of music expectancy theory: (1) individual experiences matter in the formation of expectations; (2) expectations are a dynamic process, that change and are updated with experience; (3) context plays a critical role in expectancy; and (4) schema, prototypes and statistical accounts of expectation should be treated as convenient approximations of underlying cognitive processes.

In this article, we studied the role of the topological structure of semantic networking in creating verbal aggression. It is shown that centralities such as degree, betweenness and closeness play an important role in the activation of verbal aggression in the network. We have also shown that aggressive labelled nodes with spectral clustering in different spectra are often divided into two groups, with the larger group activating more aggressive labelled nodes. In addition, the parameter of eccentric distribution from the origin is introduced to study the dispersion of aggressive nodes around the specific nodes. Hence, studying two networks with different contexts shows that the dispersion of nodes with aggressive labelling around the network's hub, as the centre of the network with political context, is much more than artistic context. In addition, different clusters of verbal aggression in the political and artistic context have the same pattern of frequency. In addition, we investigated semantic features in creating verbal aggression, showing that non-aggressive words are prone to create verbal aggression as much as aggressive words. [ABSTRACT FROM AUTHOR]

A well agreed discourse in music perception research is that affective response can be generated by music when a tendency in the music is delayed or inhibited. There is a consensus that this tendency is statistically driven, derived from exposure to culturally situated musical idioms. By presenting a neural-network inspired spreading activation model (SAM) this paper argues that the nature of the tendency is worthy of further investigation. SAM organises the music stream perceived by the listener continuously into segments such that a match with an existing ‘mental representation’ (node) is found, which is then linked to the node for the previously segmented part of the music stream, with the link between these nodes strengthening and consolidating with exposure. The currently activated segment (the music being sounded) will prime the best matching (strongest linked) node available, generating expectancy. Expectancy is defined as the most strongly primed segment, and emerges dynamically through experience with environmental and musical contexts, rather than schematic or prototypical means. Expectancy is the specific exemplar instance that the activated (currently sounding) segment of music and contextual factors prime. This hypothesis of veridical dominance has implications for enduring aspects of music expectancy theory: (1) individual experiences matter in the formation of expectations; (2) expectations are a dynamic process, that change and are updated with experience; (3) context plays a critical role in expectancy; and (4) schema, prototypes and statistical accounts of expectation should be treated as convenient approximations of underlying cognitive processes. [ABSTRACT FROM AUTHOR]

We investigate a method for formulating context- and task-specific computational models of human performance in a con-strained semantic memory task. In particular, we assume thatmemory retrieval can only use a simple process – a randomwalk – and examine whether the effect of context and taskspecifications can be captured via a straightforward networkestimation method that is sensitive to context and task. We findthat a random walk model on the context-specific networksmimics aggregate human performance.

Solving a problem requires relating the pieces of information available to each other and to the solution. We investigated how the strength of these relationships determines the likelihood of solving insight tasks based on remote associates. In these tasks, the solver is provided with several cues (e.g., drop, coat, summer) and has to find the solution that matches those cues (e.g., rain). We measured the semantic similarity between the cues and the solution (cue–solution similarity) as well as between cues (cue–cue similarity). We assume those relationships modulate two basic processes underlying insight problem-solving. First, there is an automatic activation process whereby conceptual activation spreads across a semantic network from each cue node to their associated nodes, potentially reaching the node of the solution. Thus, in general, the higher cue–solution similarity, the more likely the solution will be found (Prediction 1). Second, there is a controlled search process focused on an area in semantic space whose radius depends on competing cue–cue similarity. High cue–cue similarity will bias a search for the solution close to the provided cues because the associated nodes shared by both cues are highly coactivated. Therefore, high cue–cue similarity will have a beneficial effect when the cue–solution similarity is high but a detrimental effect when cue–solution similarity is low (Prediction 2). Our two predictions were confirmed using both verbal and pictorial remote association tasks, supporting the view that insight is dependent on an interaction of meaningful relationships between cues and solutions, and clarify the mechanisms of insight problem solving in remote associates. [ABSTRACT FROM AUTHOR]

In multilingual people, semantic knowledge is predominantly shared across languages. Providing semantic-focused treatment to people with aphasia has been posited to strengthen connectivity within association cortices that subserve semantic knowledge. In multilingual people, such treatment should result in within- and cross-language generalisation to all languages, although not equally. We investigated treatment effects in two multilingual participants with aphasia who received verb-based semantic treatment in two pre-stroke highly proficient languages. We compared within- and cross-language generalisation patterns across languages, finding within- and cross-language generalisation after treatment in the less-impaired, pre-morbidly more-proficient first-acquired language (L1). This observation supports the theory that connectivity is greater between the lexicon of a pre-morbidly more-proficient L1 and the shared semantic system than the lexicon of a pre-morbidly less-proficient later-acquired language. Our findings of within- and cross-language generalisation patterns could also be explained by both the Competing Mechanisms Theory and the theory of lingering suppression. [ABSTRACT FROM AUTHOR]

Categorization has a large impact on how people perceive theworld, especially when used to make inferences about uncer-tain features of new objects. While making these inferences,people tend to draw information from only one possible cate-gorization of a new object; in addition, people are sensitive topre-existing correlations between features. Here, we explainthese trends of feature inference using a priming-based cogni-tive process model, and show that our model is distinguishedin that it can explain not only these two main trends, but alsocases where people seem to reverse the first trend and base in-ferences on information from multiple categories.

Impaired performance in verbal fluency (VF) tasks is a frequent observation in Parkinson's disease (PD). As to the nature of the underlying cognitive deficit, it is commonly attributed to a frontal-type dysexecutive syndrome due to nigrostriatal dopamine depletion. Whereas dopaminergic medication typically improves VF performance in PD, e.g., by ameliorating impaired lexical switching, its effect on semantic network activation is unclear. Data from priming studies suggest that dopamine causes a faster decay of semantic activation spread. The aim of the current study was to examine the impact of dopaminergic medication on the dynamic change of word frequency during VF performance as a measure of semantic spreading activation. To this end, we performed a median split analysis of word frequency during phonemic and semantic VF task performance in a PD group tested while receiving dopaminergic medication (ON) as well as after drug withdrawal (i.e., OFF), and in a sample of age-matched healthy volunteers (both groups n = 26). Dopaminergic medication in the PD group significantly affected phonemic VF with improved word production as well as increased error-rates. The expected decrease of word frequency during VF task performance was significantly smaller in the PD group ON medication than in healthy volunteers across semantic and phonemic VF. No significant group-difference emerged between controls and the PD group in the OFF condition. The comparison between both treatment conditions within the PD group did not reach statistical significance. The observed pattern of results indicates a faster decay of semantic network activation during lexical access in PD patients on dopaminergic medication. In view of improved word generation, this finding is consistent with a concept of more focused neural activity by an increased signal-to-noise ratio due to dopaminergic neuromodulation. However, the effect of dopaminergic stimulation on VF output suggests a trade-off between these beneficial effects and increased error-rates. [ABSTRACT FROM AUTHOR]

The DRM (Deese–Roediger–McDermott) paradigm produces robust false memories of non-presented critical words. After studying a thematic word list (e.g., bed, rest, and pillow) participants falsely remember the critical item “sleep.” We report two false memory experiments. Study One introduces a novel use of the lexical decision task (LDT) to prime critical words. Participants see two letter-strings and make timed responses indicating whether they are both words. The word pairs Night-Bed and Dream-Thweeb both prime “sleep” but only one pair contains two words. Our primary purpose is to introduce this new methodology via two pilot experiments. The results, considered preliminary, are promising as they indicate that participants were as likely to recognize critical words (false memories) and presented words (true memories) just as when studying thematic lists. Study Two actually employs the standard DRM lists so that semantic priming is in play there as well. The second study, however, uses functional near-infrared spectroscopy (fNIRS) to measure activity in the prefrontal cortex during a DRM task which includes a deception phase where participants intentionally lie about critical lures. False and true memories occurred at high levels and activated many of the same brain regions but, compared to true memories, cortical activity was higher for false memories and lies. Accuracy findings are accompanied by confidence and reaction time results. Both investigations suggest that it is difficult to distinguish accurate from inaccurate memories. We explain results in terms of activation-monitoring theory and Fuzzy Trace Theory. We provide real world implications and suggest extending the present research to varying age groups and special populations. A nagging question has not been satisfactorily answered: Could neural pathways exist that signal the presence of false memories and lies? Answering this question will require imaging experiments that focus on regions of distinction such as the anterior prefrontal cortex. [ABSTRACT FROM AUTHOR]

Spreading activation in the cognitive network explains why music is experienced as familiar or likable. It might also be a premise for the emotion-inducing mechanisms of the BRECVEMA framework (Brain stem reflexes, Rhythmic entrainment, Evaluative conditioning, Contagion, Visual imagery, Episodic memory, Musical expectancy, Aesthetic judgment). Both perspectives constitute important aspects of music experience and are influenced by individual differences. In two studies (n = 125 and n = 153), potential indicators for spreading activation and BRECVEMA mechanisms for single instances of music listening were assessed with a new questionnaire. The results indicated that Typicality of music, Liking, and attentional Engagement underlie spreading activation. The mechanisms Evaluative conditioning and Contagion in unison (Conditioning/Contagion), as well as Visual imagery and Episodic memory could be reliably assessed. Findings revealed that (a) Engagement, Conditioning/Contagion, and Visual imagery increased with musical expertise; (b) spreading activation and mechanisms were stronger when listening to self- rather than pre-selected music; (c) sad music evoked stronger Engagement, Conditioning/Contagion, and Episodic memory when it was self-selected; (d) spreading activation and mechanisms were associated with music empathizing and systemizing and the emotion regulation strategy reappraisal; and finally, (e) regulating sadness with sad music was associated with habitual suppression and stronger Conditioning/Contagion. [ABSTRACT FROM AUTHOR]

Impaired performance in verbal fluency (VF) tasks is a frequent observation in Parkinson’s disease (PD). As to the nature of the underlying cognitive deficit, it is commonly attributed to a frontal-type dysexecutive syndrome due to nigrostriatal dopamine depletion. Whereas dopaminergic medication typically improves VF performance in PD, e.g., by ameliorating impaired lexical switching, its effect on semantic network activation is unclear. Data from priming studies suggest that dopamine causes a faster decay of semantic activation spread. The aim of the current study was to examine the impact of dopaminergic medication on the dynamic change of word frequency during VF performance as a measure of semantic spreading activation. To this end, we performed a median split analysis of word frequency during phonemic and semantic VF task performance in a PD group tested while receiving dopaminergic medication (ON) as well as after drug withdrawal (i.e., OFF), and in a sample of age-matched healthy volunteers (both groups n = 26). Dopaminergic medication in the PD group significantly affected phonemic VF with improved word production as well as increased error-rates. The expected decrease of word frequency during VF task performance was significantly smaller in the PD group ON medication than in healthy volunteers across semantic and phonemic VF. No significant group-difference emerged between controls and the PD group in the OFF condition. The comparison between both treatment conditions within the PD group did not reach statistical significance. The observed pattern of results indicates a faster decay of semantic network activation during lexical access in PD patients on dopaminergic medication. In view of improved word generation, this finding is consistent with a concept of more focused neural activity by an increased signal-to-noise ratio due to dopaminergic neuromodulation. However, the effect of dopaminergic stimulation on VF output suggests a trade-off between these beneficial effects and increased error-rates.

In this article, the famous random walk model is exploited as a model of stochastic processes to retrieve some specific words which are used in social media by users. By spreading activation on semantic networking, this model can predict the probability of the words' activation, including all probabilities in different steps. In fact, the trend of probability in different steps is shown and the result of two different weights, when the steps tend to infinity is compared. In addition, it is shown that the results of the random walk model are aligned with the experimental psychological tests, showing that, as a model for semantic memory, it is a suitable model for retrieving in social media.

Memory is considered to be a flexible and reconstructive system. However, there is little experimental evidence demonstrating how associations are falsely constructed in memory, and even less is known about the role of the self in memory construction. We investigated whether false associations involving non-presented stimuli can be constructed in episodic memory and whether the self plays a role in such memory construction. In two experiments, we paired participants' own names (i.e., self-reference) or the name "Adele" (i.e., other-reference) with words and pictures from Deese/Roediger–McDermott (DRM) lists. We found that (1) participants not only falsely remembered the non-presented lure words and pictures as having been presented, but also misremembered that they were paired with their own name or "Adele," depending on the referenced person of related DRM lists; and (2) there were more critical lure–self associations constructed in the self-reference condition than critical lure–other associations in the other-reference condition for word but not for picture stimuli. These results suggest a self-enhanced constructive effect that might be driven by both relational and item-specific processing. Our results support the spreading-activation account for constructive episodic memory. [ABSTRACT FROM AUTHOR]

Models of spatial reasoning often assume distinct visual andspatial representations. In particular, the visual impedance effect– slower response time when more visual details are representedin three-term series spatial reasoning tasks – has beentaken as evidence for the distinctive roles of visual and spatialrepresentations. In this paper, we show that a memorymodel of spreading activation based on the ACT-R architecturecan explain the visual impedance effect without the assumptionof distinct visual and spatial representations. Usingthe same memory representation, varying levels of visual featuresassociated with an object are represented in the model.The visual impedance effect is explained by the spreading activationmechanism of ACT-R. The model not only providesa more parsimonious explanation to the visual impedance effect,but also leads to testable predictions of a wide range ofmemory effects in spatial reasoning.

We present a computational cognitive model of mind wandering,an important cognitive phenomenon whose mechanismsare involved in insight, problem-solving, and creativity. Themodel posits that mind wandering begins when one is notengaged in goal-oriented cognition, whether when betweentasks or when in the middle of a task but not actively thinkingabout one’s goal. At such times, the model thinks about other,highly-activated thoughts in memory. This model sheds lighton both how task-oriented and more basic cognitive processesinteract, as well as how mind wandering content is generated;both unresolved questions for mind wandering research. Wecompare our model against data presented by McVay and Kane(2013), who induced mind wandering in a laboratory setting byembedding participants’ personal goals and concerns in a lexicalSART task. Overall, our model matched the data’s mindwandering rates very well. We discuss implications and futurework on the model.

We examine the fan effect in overlapping data sets and logicalinference. Three experiments are presented and modeledusing the ACT-R cognitive architecture. The results raiseissues over the scope of the memories that determine the faneffect and the use of search strategies to retrieve frommemory

Hypomanic personality, hyperthymic temperament and irritable temperament are considered as psychological vulnerability factors to bipolar disorders. Semantic memory is impaired in bipolar patients. Spreading activation is among the probable candidates for accounting this impairment. The aim of this study was to assess spreading activation according to vulnerability factors continuum to determine whether it could be a factor of vulnerability to bipolar disorders. A sample of 61 healthy volunteers was recruited. Spreading activation was assessed by semantic mediated priming implemented in a double lexical decision task. Results shown that semantic mediated priming was negatively associated to hyperthymic temperament and irritable temperament. Impairment in semantic memory, and more specifically spreading activation, appear to be a cognitive factor of vulnerability to bipolar disorders. Our results can contribute to a better understanding of semantic impairment in vulnerable population and in bipolar disorder.

Hypomanic personality, hyperthymic temperament and irritable temperament are considered as psychological vulnerability factors to bipolar disorders. Semantic memory is impaired in bipolar patients. Spreading activation is among the probable candidates for accounting this impairment. The aim of this study was to assess spreading activation according to vulnerability factors continuum to determine whether it could be a factor of vulnerability to bipolar disorders. A sample of 61 healthy volunteers was recruited. Spreading activation was assessed by semantic mediated priming implemented in a double lexical decision task. Results shown that semantic mediated priming was negatively associated to hyperthymic temperament and irritable temperament. Impairment in semantic memory, and more specifically spreading activation, appear to be a cognitive factor of vulnerability to bipolar disorders. Our results can contribute to a better understanding of semantic impairment in vulnerable population and in bipolar disorder. [ABSTRACT FROM AUTHOR]

Creativity is commonly defined as a process that leads to a novel and useful outcome (an idea, product, or expression). However, two dilemmas about this definition remain unresolved: (1) A strict application of usefulness is difficult to apply to artistic works: who decides what artwork is useful, and how it is useful? (2) The implied boundary conditions of novelty are problematic: The default perspective is that novelty has a monotonic increasing relationship with creativity, or it is categorical—i.e., novel or not. To address these dilemmas, this paper proposes a spreading activation model of creativity (SAMOC), a model built on a brain-architecture-inspired vast interconnected network of nodes, each node representing information, and assigned meanings through interaction with the environment. Nodes are linked to each other according to principles of temporal contiguity (linking objects/events in time) and similarity (linking objects/events by shared features). A node activated by attention spreads through the network through previously linked nodes. Nodes that are well connected activate each other easily, while those that are weakly connected do not. Net total activation corresponds to positive affect (e.g., pleasure), and this is proposed as an essential criteria for a creative work of art, instead of usefulness. SAMOC also predicts that creativity will be optimized at an intermediate, not extreme, level of novelty. Too much activation will occur with the activation of preexisting ideas (hence reproduction rather than creativity), and too much novelty will not produce spread of activation. The two functions (spreading activation and the novelty curve) are superposed to demonstrate this optimal novelty hypothesis. Early evidence of the hypothesis comes from the data that some great works of art were critically rejected at premiers (suggesting excessive novelty), but after sufficient repetition (and therefore linking) became suitably associated and commenced generating activation. The hypothesis has important implications for future empirical research programs on creativity, and for the definition of creativity itself.

Creativity is commonly defined as a process that leads to a novel and useful outcome (an idea, product, or expression). However, two dilemmas about this definition remain unresolved: (1) A strict application of usefulness is difficult to apply to artistic works: who decides what artwork is useful, and how it is useful? (2) The implied boundary conditions of novelty are problematic: The default perspective is that novelty has a monotonic increasing relationship with creativity, or it is categorical—i.e., novel or not. To address these dilemmas, this paper proposes a spreading activation model of creativity (SAMOC), a model built on a brain-architecture-inspired vast interconnected network of nodes, each node representing information, and assigned meanings through interaction with the environment. Nodes are linked to each other according to principles of temporal contiguity (linking objects/events in time) and similarity (linking objects/events by shared features). A node activated by attention spreads through the network through previously linked nodes. Nodes that are well connected activate each other easily, while those that are weakly connected do not. Net total activation corresponds to positive affect (e.g., pleasure), and this is proposed as an essential criteria for a creative work of art, instead of usefulness. SAMOC also predicts that creativity will be optimized at an intermediate, not extreme, level of novelty. Too much activation will occur with the activation of preexisting ideas (hence reproduction rather than creativity), and too much novelty will not produce spread of activation. The two functions (spreading activation and the novelty curve) are superposed to demonstrate this optimal novelty hypothesis. Early evidence of the hypothesis comes from the data that some great works of art were critically rejected at premiers (suggesting excessive novelty), but after sufficient repetition (and therefore linking) became suitably associated and commenced generating activation. The hypothesis has important implications for future empirical research programs on creativity, and for the definition of creativity itself. [ABSTRACT FROM AUTHOR]

The type of a recall task may substantially influence the effects of learning by retrieval practice. In a within-subject design, 54 university students studied two expository texts, followed by retrieval practice with either short-answer tasks (targeted retrieval) or a free-recall task (holistic retrieval). Concerning the direct effects of retrieval practice, short-answer tasks led to increased retention of directly retrieved targeted information from the learning contents, whereas free-recall tasks led to better retention of further information from the learning contents. Concerning indirect effects, short-answer tasks improved metacognitive calibration; free-recall tasks increased self-efficacy and situational interest. These findings confirm the assumption that the effects of retrieval practice depend on the type of recall task: short-answer tasks help us remember targeted information units and foster metacognitive calibration. Free-recall tasks help us remember a broader spectrum of information, and they foster motivational factors. [ABSTRACT FROM AUTHOR]

Semantically enhanced information retrieval is aimed at improving classical information retrieval methods and goes way beyond plain Boolean keyword matching with the main goal of better serving implicit and ambiguous information needs. As a de-facto pre-requisite to semantic information retrieval, different information extraction techniques are used to mine unstructured text for underlying knowledge. In this paper, we present a method that combines both information extraction and information retrieval to enable semantic search in natural language texts. First, we apply semantic role labeling to automatically extract event-oriented information found in natural language texts to a Resource Description Framework knowledge graph leveraging semantic web technology. Second, we investigate how a custom flavored graph traversal spreading activation algorithm can be employed to interpret user's information needs on top of the previously extracted knowledge base. Finally, we present an assessment on the applicability of our method for semantically enhanced information retrieval. An experimental evaluation on partial WikiQA dataset shows the strengths of our approach and also unveils common pitfalls that we use as guidelines to draw further work directions in the open-domain semantic search field. [ABSTRACT FROM AUTHOR]

An understanding of cognitive control is crucial for understanding high-level cognition and delineating the functional role of prefrontal cortex in supporting complex cognitive operations. In this paper, we approach the problem of cognitive control by examining the control needs of SHRUTI, a neurally plausible and cognitively motivated model of inference and decision-making. It is shown that processing via spreading activation has a number of limitations with respect to inference and decision-making, and specific forms of controlled processing is required to overcome these limitations. We propose a set of primitive, neurally plausible control mechanisms, including monitoring, filtering, selection, maintenance, organization, and manipulation, describe connectionist implementations of these primitive mechanisms, and demonstrate the use of several of these primitives in a complex control process. (c) 2004 Published by Elsevier B.V.