Generating Scripts From Memory

A variation of the Raaijmaker and Shiffrin (1981) retrieval model is proposed to account for typical script generation data. In our model, knowledge is represented as an associative network with propositions as the nodes. A control process which utilizes temporal information in these propositions supplements the probabilistic memory retrieval process to produce ordered retrieval of scriptal events. Simulations are reported which provide a good qualitative fit to data collected from subjects in both script generation and free association tasks. These results support a view of memory as an unorganized knowledge base rather than a stable, organized structur

An empirical study of software reuse by experts in object-oriented design

This paper presents an empirical study of the software reuse activity by expert designers in the context of object-oriented design. Our study focuses on the three following aspects of reuse : (1) the interaction between some design processes, e.g. constructing a problem representation, searching for and evaluating solutions, and reuse processes, i.e. retrieving and using previous solutions, (2) the mental processes involved in reuse, e.g. example-based retrieval or bottom-up versus top-down expanding of the solution, and (3) the mental representations constructed throughout the reuse activity, e.g. dynamic versus static representations. Some implications of these results for the specification of software reuse support environments are discussed

Foraging in semantic fields : how we search through memory

When searching for concepts in memory-as in the verbal fluency task of naming all the animals one can think of-people appear to explore internal mental representations in much the same way that animals forage in physical space: searching locally within patches of information before transitioning globally between patches. However, the definition of the patches being searched in mental space is not well specified. Do we search by activating explicit predefined categories (e.g., pets) and recall items from within that category (categorical search), or do we activate and recall a connected sequence of individual items without using categorical information, with each item recalled leading to the retrieval of an associated item in a stream (associative search), or both? Using semantic representations in a search of associative memory framework and data from the animal fluency task, we tested competing hypotheses based on associative and categorical search models. Associative, but not categorical, patch transitions took longer to make than position-matched productions, suggesting that categorical transitions were not true transitions. There was also clear evidence of associative search even within categorical patch boundaries. Furthermore, most individuals' behavior was best explained by an associative search model without the addition of categorical information. Thus, our results support a search process that does not use categorical information, but for which patch boundaries shift with each recall and local search is well described by a random walk in semantic space, with switches to new regions of the semantic space when the current region is depleted

Functional Fixedness in Creative Thinking Tasks Depends on Stimulus Modality

This article may not exactly replicate the final version published in the APA journal. It is not the copy of record.Pictorial examples during creative thinking tasks can lead participants to fixate on these examples and reproduce their elements even when yielding suboptimal creative products. Semantic memory research may illuminate the cognitive processes underlying this effect. Here, we examined whether pictures and words differentially influence access to semantic knowledge for object concepts depending on whether the task is close- or open-ended. Participants viewed either names or pictures of everyday objects, or a combination of the two, and generated common, secondary, or ad hoc uses for them. Stimulus modality effects were assessed quantitatively through reaction times and qualitatively through a novel coding system, which classifies creative output on a continuum from top-down-driven to bottom-up-driven responses. Both analyses revealed differences across tasks. Importantly, for ad hoc uses, participants exposed to pictures generated more top-down-driven responses than those exposed to object names. These findings have implications for accounts of functional fixedness in creative thinking, as well as theories of semantic memory for object concepts

Bear in mind: the role of personal background in semantic animal fluency – The SMART-MR study

ObjectivesSemantic fluency is a prominent neuropsychological task, typically administered within the category ‘animals’. With the increasing development of novel item-level metrics of semantic fluency, a concern around the validity of item-level analyses could be that personal background factors (e.g., hobbies like birdwatching or fishing) may disproportionally influence performance. We analyzed animal fluency performance at the item level and investigated the prevalence of individuals with abundant knowledge in specific classes of animals (e.g., birds, fish, insects) and the relationship of such knowledge with personal background factors and other cognitive tasks (episodic memory and executive functioning).MethodParticipants included 736 Dutch middle-aged to older adults from the SMART-MR cohort (mean age 58 ± 9.4 years, 18% women). Individuals were asked to name as many animals as possible for 2 min. Number of people with abundant animal class knowledge was calculated for the ability to recall a series of minimum ≥5 and up to ≥15 animals within a specific class with at most one interruption by an animal from another class. Subsequent analyses to investigate relationships of abundant class knowledge with sociodemographic characteristics (t-tests and chi-square tests) and cognitive performance (linear regressions) were performed for a cut-off of ≥10 animals within a specific class (90th percentile), with a sensitivity analysis for ≥7 animals (67th percentile).ResultsA total of 416 (56.2%) participants recalled a series of ≥5 animals from a specific class, 245 (33.3%) participants recalled ≥7, 78 (10.6%) participants recalled ≥10, and 8 (1.1%) participants recalled ≥15. Those who recalled a series of at least 10 animals within a class were older, more often men, and more often retired than those who did not. Moreover, they had a higher total score on animal fluency, letter fluency (i.e., executive functioning), and episodic memory tasks compared to those who did not.DiscussionOur results suggest that the benefit of abundant animal class knowledge gained by personal background does not disproportionally influence animal fluency performance as individuals with such knowledge also performed better on other cognitive tasks unrelated to abundant knowledge of animal classes

Bear in mind: the role of personal background in semantic animal fluency - The SMART-MR study

OBJECTIVES: Semantic fluency is a prominent neuropsychological task, typically administered within the category 'animals'. With the increasing development of novel item-level metrics of semantic fluency, a concern around the validity of item-level analyses could be that personal background factors (e.g., hobbies like birdwatching or fishing) may disproportionally influence performance. We analyzed animal fluency performance at the item level and investigated the prevalence of individuals with abundant knowledge in specific classes of animals (e.g., birds, fish, insects) and the relationship of such knowledge with personal background factors and other cognitive tasks (episodic memory and executive functioning). METHOD: Participants included 736 Dutch middle-aged to older adults from the SMART-MR cohort (mean age 58 ± 9.4 years, 18% women). Individuals were asked to name as many animals as possible for 2 min. Number of people with abundant animal class knowledge was calculated for the ability to recall a series of minimum ≥5 and up to ≥15 animals within a specific class with at most one interruption by an animal from another class. Subsequent analyses to investigate relationships of abundant class knowledge with sociodemographic characteristics ( t-tests and chi-square tests) and cognitive performance (linear regressions) were performed for a cut-off of ≥10 animals within a specific class (90th percentile), with a sensitivity analysis for ≥7 animals (67th percentile). RESULTS: A total of 416 (56.2%) participants recalled a series of ≥5 animals from a specific class, 245 (33.3%) participants recalled ≥7, 78 (10.6%) participants recalled ≥10, and 8 (1.1%) participants recalled ≥15. Those who recalled a series of at least 10 animals within a class were older, more often men, and more often retired than those who did not. Moreover, they had a higher total score on animal fluency, letter fluency (i.e., executive functioning), and episodic memory tasks compared to those who did not. DISCUSSION: Our results suggest that the benefit of abundant animal class knowledge gained by personal background does not disproportionally influence animal fluency performance as individuals with such knowledge also performed better on other cognitive tasks unrelated to abundant knowledge of animal classes

Exploring the Creative Process: Integrating Psychometric and Eye-Tracking Approaches

This exploratory study aims at integrating the psychometric approach to studying creativity with an eye-tracking methodology and thinking-aloud protocols to potentially untangle the nuances of the creative process. Wearing eye-tracking glasses, one hundred adults solved a drawing creativity test – The Test of Creative Thinking-Drawing Production (TCT-DP) – and provided spontaneous comments during this process. Indices of visual activity collected during the eye-tracking phase explained a substantial amount of variance in psychometric scores obtained in the test. More importantly, however, clear signs of methodological synergy were observed when all three sources (psychometrics, eye-tracking, and coded thinking-aloud statements) were integrated. The findings illustrate benefits of using a blended methodology for a more insightful analysis of creative processes, including creative learning and creative problem-solving

The effects of scopolamine upon control of attention and memory in humans

Research into the effects of scopolamine hydrobromide, a post­synaptic cholinergic receptor blocking drug, upon cognition in humans has been conducted for at least two decades. In that time, a distinct pattern of effects has emerged. Within a dose range of 0.3 to 1.2 mg (oral), scopolamine has been found to impair the acquisition of new information in verbal and spatial learning tasks, to reduce stimulus sensitivity in tests of vigilance and to impair selective attention. Generally it is thought that information retrieval, both of newly learned and autobiographical material, is unaffected by this drug. A primary reason for research interest in scopolamine is that the effects have been found to resemble the pattern of impairment found in advanced age, and particularly in Alzheimer's Disease (AD). This is often referred to as the 'Scopolamine model of dementia'. Coupled with the observation of extensive damage to CNS cholinergic neurons in AD, the hypothesis has emerged that acetylcholine activity influences many important cognitive processes. Recent theoretical analyses of cognitive loss in AD have proposed that there is a selective impairment to effortful (i.e. active, conscious) processes, whereas the more automatic (i.e. reflexive, unconscious) aspects of cognition remain intact. If the scopolamine model is to remain valid in this perspective, then it should be possible to show that, in normal humans, the effects of the drug are specific to effortful cognitive control processes. This thesis describes six experiments designed to test this prediction. It is presented in three parts. In Part I, two experiments examined the effects of O. 6mg and O. 9mg oral scopolamine upon the control of attention to targets in visual space. Results confirmed the prediction that the ability to detect stimuli in high probability locations on a VDU is impaired, while detection of stimuli in low probability locations is enhanced. It was argued that the drug broadened the attentional focus, and that this is due to a general reduction in cognitive control. In Part II, two studies sought to find evidence that the drug impairs the active selection of information from semantic memory. Here, subjects were not provided with material to learn, but rather were asked to sustain the retrieval of items from natural semantic categories for extended periods (8 to 12 min). In the second study of this pair, subjects were also constrained as to the type of retrieval strategy they could use. Results failed to confirm the prediction. The drug had no main or interactive effects on active control over semantic memory retrieval. In Part III, two studies tested the prediction that scopolamine would selectively impair the more difficult, controlled aspects of encoding and retrieval following presentation of verbal material (i.e. an episodic memory task) in two sensory modalities (auditory and visual). Subjects were required to recall lists of words, and to actively group their recall on the basis of the items' sensory modality. The first study found that the drug impaired recall, but not recognition, and did not have an effect on more automatic phenomena such as word priming effects and the recall advantage for auditory material. In addition, there was some evidence from statistical interactions that the drug impaired subjects' ability to actively cluster the presented material on the basis of input modality. The second experiment examined effects of scopolamine upon list learning and modality clustering when subjects were given five attempts to recall the same i terns. This experiment introduced two levels of task difficulty, by varying the extent to which item input modality was consistent across learning trials. Pilot testing (non-drug) revealed that list learning and clustering ability were significantly impaired in the variable, as compared to consistent, modality condition. In the full experiment, scopolamine impaired total recall but not recognition. The drug did not directly effect subjects' ability to group items on the basis of modality, and the size of the drug effect on immediate recall was similar for both the easy (i.e. consistent modality) and difficult (i.e. variable modality) learning trials. There were some interactions between drug and task variables which indicated a weak effect upon attention Taken together, these six experiments show the following pattern. Control over visual attention is impaired by scopolamine, and this agrees with some previous research. However, this reduction in cognitive control appears to be specific, rather than general, since the attempts to find an effect of the drug on active control of retrieval from semantic memory and the conscious organisation of material in episodic memory were unsuccessful. In theoretical terms, this series of experiments does not support the view that anticholinergic drug effects are specific to effortful processing. It was argued that the pattern of drug effects observed here is not simply due to low potency of a O. 9mg oral dose. Numerous previous experiments have observed subtle effects of scopolamine 0.9mg oral (and lower doses) on various measures of cognitive function. It was concluded that a low to moderate dose of oral scopolamine does have selective effects on different cognitive processes, but that this selectivity is not related to the amount of cognitive effort involved in the tasks. This work has identified some important limits to the scopolamine model of dementia, and extended research with this drug into several domains of human memory not previously examined. The implications for future research are discussed