The present study compares the cognitive processes underlying two perceptual implicit memory tests (word stem completion and word fragment completion) and four explicit memory tests (word stem cued recall, word fragment cued recall, free recall, and recognition). Like many previous studies (and as is predicted by most current memory theories) manipulation of the level, or depth of cognitive processing engaged during the study phase dissociated the explicit tests from the implicit tests. That is, for the explicit tests, processing the study items under a deep level of processing resulted in a greater number of words being recalled or recognized (compared to performance under a shallow level of processing at study). On the implicit tests, this manipulation had very little effect. These differential effects are often interpreted as evidence that qualitatively different processes underlie performance on implicit and explicit tests. However, in looking at which (instead of how many) items are produced on the tests, the conclusions are somewhat different. In the present study this "unit analysis" approach described by Rubin (1985) showed that: (1) implicit and explicit tests correlated more strongly within stimulus type (stem/fragment) than they did within test type (implicit/explicit), (2) both part-word cued recall tests (word stem and word fragment cued recall) correlated strongly with recognition even though they correlated only modestly with each other, and (3) free recall did not correlate positively with any of the other tests (implicit or explicit). These results are explained in terms of a generate/recognize model that incorporates transfer appropriate processing assumptions. Briefly, it is suggested that the implicit tests and their explicit counterparts involve the same data-limited process, and that recognition is not similarly limited--relying almost exclusively on conceptually driven processes. However, this generate/recognize explanation fails to explain why free recall does not correlate positively with any of the other tests. The failure of free recall to correlate positively with any of the other tests is interpreted as suggesting that free recall may rely on qualitatively different processes.

This dissertation reports findings from two laboratory experiments and a field study demonstrating significant reliance by users on interface layout information in interactive tasks. In Experiment l, a paradigm was introduced where either the layout of the interface was changed or labels were removed, after participants completed a minimum of eleven trials of a routine computer-based task. Since layout change had a more detrimental effect on performance, in Experiment 2, two methods expected to mediate that effect were explored: the addition of color and a layout based on a simple preexisting rule of top-to-bottom control order. Only the latter was effective, showing that introducing an interface layout that leverages preexisting knowledge can actually improve task performance. In the field study, a methodology was developed to put these findings to the test at a local family medicine clinic using an electronic medical records system. By studying nurses' use of an existing data entry form, a new form was designed to more closely follow their workflow. Similar to the top-to-bottom control order manipulation in Experiment 2, the new form layout seemed to produce better performance and was liked better by the nurses. Thus, in contrast to the vast body of literature in the field that has emphasized the importance of label information (e.g., Polson & Lewis, 1990) and goal structure (e.g., John & Kieras, 1996) in computer-based tasks, these findings reveal that users quickly learn to rely on layout information.

The commission of error is often perceived as the result of such internal attributes as negligence, laziness, carelessness, and inattention. In organizational settings, such a perception often leads to the administration of punitive actions against the responsible individual. Recent research on error, however, has moved thinking from a "conventional wisdom" perspective of human error to a systems perspective. According to this systems perspective, humans are remarkably reliable "stand-alone" systems, and errors tend to arise primarily when humans interact with technological systems. Errors can be triggered by technology and its environment, as a result of the way these factors interact and challenge human limitations. Byrne and Bovair (1997) found that the commission of a particular type of error, postcompletion error, is related to a high working memory load imposed by external forces or task complexity. Two experiments were designed to assess the effects of typical organizational responses to error on the commission of postcompletion errors over time. Because organizations tend to assume that errors are under the control of the individual, methods such as reprimands and re-instruction are often administered to "motivate" individuals to not commit errors. Similarly, praise is often administered to encourage the continuation of appropriate behavior. A systems perspective, however, would argue that a troublesome task should be redesigned to accommodate the limitations of the human cognitive system under certain circumstances. The results of the experiments reported here indicated that, over time, simple tasks were learned so well that people made few errors, and therefore, responses to error appeared to have little effect on the commission of error. It was found, however, that when a task was redesigned, participants were much quicker at executing a critical redesigned task step than participants who were reprimanded, received re-instruction, or were praised for their performance. This indicates that the cost of low-error performance for these participants came at the cost of increased time to complete the critical step, further indicating that these participants had to consciously expend effort to not commit the error.

Web search engines are the primary method for finding information in the vast World Wide Web, yet little empirical research of them has been conducted. This study examined how well search engines' relevancy ratings of Web sites matched users' ratings. Eighty-one people rated Web sites in three different topic areas that were delivered as top sites by Infoseek and/or HotBot. To ensure fair ratings, participants were unaware of the ratings assigned by the search engines, or even that search engines had generated the sites. Individual difference characteristics of the raters (e.g., browser-searcher, level of knowledge and interest in topic) were also collected. Agreement as to the top sites was quite low among search engines. However, people showed very high levels of agreement and reliability. Search engines' ratings did not correspond well with the raters' ratings. Nevertheless, Infoseek performed better than HotBot on every measure of agreement with user ratings.

The present studies attempt to characterize the representations that support long-term, cross-modality priming, with the main hypothesis being that auditory-to-visual priming for words is supported by phonological representations. The purpose of Experiments 1 and 2 was to develop and refine an experimental paradigm for manipulating phonological processing. Results indicate that, regardless of study condition, semantic or phonological-articulatory, using homophonic nonwords as foils in a lexical decision task can eliminate phonological priming of both the speed and accuracy of responding. The purpose of Experiment 3 was to apply this paradigm to cross-modality priming. To the extent that it is mediated by phonological representations, cross-modality priming should be reduced in the context of homophonic foils. The findings support the hypothesis: Robust same-modality priming was obtained in both the reaction time and error data, whereas cross-modality priming was not significant. There was, however, a small amount of cross-modality priming in the RT data, prompting further exploration of this issue. Experiment 4 included type of nonword foil, nonhomophonic and homophonic, as a between-participants variable. The study task was changed from tangibility judgments to naming aloud. The pattern of results was similar to that of Experiment 3, with robust cross-modality priming when foils were nonhomophonic nonwords, and very attenuated cross-modality priming when the foils sounded like words. In Experiment 5, visual-to-visual and auditory-to-visual priming for words was compared in the lexical decision task when foils were nonhomophonic nonwords or homophonic nonwords. A recognition memory condition was also included. Cross-modality priming for words was about half as large as repetition priming when nonhomophonic nonwords served as the foils, but was virtually eliminated in the context of homophonic nonwords. Same-modality priming was unaffected by foil manipulation, and there were no modality differences in the recognition condition. Taken together, this pattern of findings suggests that visual-to-visual word priming is mediated largely by orthographic representations, and auditory-to-visual cross-modality word priming is mediated largely by phonological representations.

No description available.

The objective of this study was to identify subgroups in patients with Alzheimer's Disease (AD), based on a dissociation in their performance on visuospatial tasks: one subgroup with predominant impairment on object recognition or the "What" system, and another subgroup with predominant impairment in spatial recognition or the "Where" system. Also, an attempt was made to clarify the relationship between attention on these two visuospatial processes. Amongst twenty-four patients with AD, we identified two pairs of patients with dissociated performances. However, except for one case, the dissociations found were mainly based on the prominent impairment of the spatial ability or the "Where" system. Based on the performance of cohort, our results suggested that spatial abilities are more impaired than the object recognition ability. In addition the results showed that AD also affects the central executive system, and that the impairments in visuospatial processes, especially the "What" system, may at least partly be explained by deficits in this system. These findings also indicate that certain sub-components of visuospatial processes can be distinctively affected by AD.

The categorical perception paradigm was used to compare French/English bilinguals' and French and English monolinguals' categorization of code-switched words. A previous study by Burki-Cohen et al. (1987) showed that bilinguals' categorization of a cross-language continuum that varied from a French word to an English word was different when the words were presented in the context of a French or an English carrier phrase. Using the same stimuli the present study examined whether the effects of base language (i.e. the carrier phrase) are due to processing specific to bilinguals or are mediated by general phonetic or auditory processes. Results showed that all three groups were affected by the base language in the same way, suggesting that general processes were involved. These findings indicate that manipulating a carrier phrase does not ensure that a level of language processing is invoked which can reveal categorization processes that are particular to bilinguals.

<p> The purpose of this study was to explore treatment options for aggression-related disorders. Two activities were examined to validate their use as frustration-reduction techniques --yoga and therapeutic drumming. Twenty-two college students were randomly assigned to participate in one of three groups--yoga, drumming, or silence (control)--following experimentally-induced frustration using a computerized Stroop color-word technique. Self-reported emotion levels and physiological responses were tracked at baseline, post-frustration, and post-treatment to measure responses to treatment. Results indicate that self-reported frustration levels were significantly reduced in all experimental groups, but physiologic responses showed no significant changes. A Multivariate Analysis of Variance (MANOVA) indicated no significant difference in lowered frustration for any of the treatment groups, suggesting that they are equally effective. These results also suggest that the passage of time may be key to successful emotion regulation. Further study should examine control variables and methodology to identify other factors that may be involved in regulating aggressive emotions. </p>

<p> Individuals with profound multiple disabilities (PMD) have significant deficits in intellectual functioning in addition to physical disabilities and associated medical conditions. Often, these individuals have communication deficits making the expression of basic wants and needs challenging. Given the communication difficulties associated with profound multiple disabilities, there is a need for systematic assessment to better understand emotional responses of individuals with profound multiple disabilities, including happiness responses. Methods to identify emotions of individuals with profound multiple disabilities have improved over the past few years. Within the field of psychology, there has been a growing base of empirical information regarding happiness. One of the defining concerns of positive psychologists is the positive emotion of happiness. Applied behavior analysis provides a body of research and theoretical underpinnings to examine theoretical gaps in expression of emotions for individuals who have profound multiple disabilities. This quantitative study assessed whether presentation of preferred items and activities during multiple periods of the day (and over multiple days) increased indices of happiness (over time/sustained) in individuals with PMD. A multiple baseline design across participants was utilized to measure changes in indices of happiness of the participants. Participants were recruited from an adult day activity program specializing in providing assistance to individuals with disabilities. For Mary, baseline indices of happiness were 26.67% of intervals, increasing 6.76% during intervention to 33.43%. For Caleb, baseline indices of happiness were 20.84% of intervals, increasing 6.34% during intervention to 27.18%. For Mark, baseline indices of happiness were 40.00% of intervals, increasing 12.75% during intervention to 52.75%. Overall interobserver agreement was 82.8%, with interobserver agreement observations occurring during 63.04% of the observations. The results of the investigation demonstrated that presenting preferred items and activities increased the indices of happiness compared to baseline rates of indices of happiness. Results may have been more robust if the participants were assessed for overall responsiveness patterns prior to the initiation of measurement of indices of happiness.</p>