Much of cognitive science research and almost all of AI research into problem solving has focused on the use of verbal or propositional representations. However, there is significant evidence that humans solve problems using different representational modalities, including visual or iconic ones. In this dissertation, I investigate visual problem solving from the perspectives of autism, psychometrics, and AI. Studies of individuals on the autism spectrum show that they often use atypical patterns of cognition, and anecdotal reports have frequently mentioned a tendency to "think visually." I examined one precise characterization of visual thinking in terms of iconic representations. I then conducted a comprehensive review of data on several cognitive tasks from the autism literature and found numerous instances indicating that some individuals with autism may have a disposition towards visual thinking. One task, the Raven's Progressive Matrices test, is of particular interest to the field of psychometrics, as it represents one of the single best measures of general intelligence that has yet been developed. Typically developing individuals are thought to solve the Raven's test using largely verbal strategies, especially on the more difficult subsets of test problems. In line with this view, computational models of information processing on the Raven's test have focused exclusively on propositional representations. However, behavioral and fMRI studies of individuals with autism suggest that these individuals may use instead a predominantly visual strategy across most or all test problems. To examine visual problem solving on the Raven's test, I first constructed a computational model, called the Affine and Set Transformation Induction (ASTI) model, which uses a combination of affine transformations and set operations to solve Raven's problems using purely pixel-based representations of problem inputs, without any propositional encoding. I then performed four analyses using this model. First, I tested the model against three versions of the Raven's test, to determine the sufficiency of visual representations for solving this type of problem. The ASTI model successfully solves 50 of the 60 problems on the Standard Progressive Matrices (SPM) test, comparable in performance to the best computational models that use propositional representations. Second, I evaluated model robustness in the face of changes to the representation of pixels and visual similarity. I found that varying these low-level representational commitments causes only small changes in overall performance. Third, I performed successive ablations of the model to create a new classification of problem types, based on which transformations are necessary and sufficient for finding the correct answer. Fourth, I examined if patterns of errors made on the SPM can provide a window into whether a visual or verbal strategy is being used. While many of the observed error patterns were predicted by considering aspects of the model and of human behavior, I found that overall error patterns do not seem to provide a clear indicator of strategy type. The main contributions of this dissertation include: (1) a rigorous definition and examination of a disposition towards visual thinking in autism; (2) a sufficiency proof, through the construction of a novel computational model, that visual representations can successfully solve many Raven's problems; (3) a new, data-based classification of problem types on the SPM; (4) a new classification of conceptual error types on the SPM; and (5) a methodology for analyzing, and an analysis of, error patterns made by humans and computational models on the SPM. More broadly, this dissertation contributes significantly to our understanding of visual problem solving.

This dissertation study attempts to understand excessive buying, a phenomenon of both theoretical and practical interest. I define excessive buying as "an individual type of buying behavior whereby consumers repetitively spend more than they should based on financial considerations". I develop a conceptual typology of excessive buying, building on the time-inconsistent preferences and automaticity theory. The new typology categorizes five specific types of excessive buying behavior: 1) habitual, 2) possessive, 3) remedial, 4) rewarding, and 5) out-of-control. Based on past literature and the typology, I generate scale items to capture the conceptual and logical variance in excessive buying. Psychometric properties of the scale are tested via Confirmatory Factor Analysis using a student and random adult sample. Nomological validity of the scale is confirmed by testing hypotheses formulated based on hedonic shopping values and the self-defeating behavior theory. The empirical analyses suggest that excessive buying results from stress, using shopping as an escape from reality, and little consideration for the potential outcomes of one's current behavior. Excessive buying leas to both financial problems and negative emotions.

Thesis (M.A.)--James Madison University, 2009. / Includes bibliographical references.

This research is an investigation into the Apil B as a culture fair assessment tool for the purpose of recruitment and selection. The Employment Equity Act stipulates that "psychological testing and other similar assessments are prohibited unless the test or assessment being used :-a) has been shown to be valid and reliable b) can be fairly applied to all employees and c) is not biased against any employee" (Employment Equity Act, 1998). The primary objective of this research is to evaluate the Apil B with regard to validity. reliability, cultural fairness, and bias via a consideration of the attitudes, opinions, and feelings of psychometric test administrators in the Kwa-Zulu Natal region. The secondary objective is to ascertain whether the Employment Equity legislation has influenced the attitudes of test administrators toward psychometric testing, and the implications for psychometric testing in South Africa following the Act. The sample in this research consists of 20 qualified test administrators of the Apil B. The administrators are affiliated with the following companies : Beacon, Durban Electricity, Profiled Appointments, Mondi, McCann and Associates, Saunders and Associates, Tetrapak, lthaJa, and Mangosuthu Technikon. Qualitative and quantitative methods are used. A self-administered questionnaire is used to investigate the attitudes, opinions, and feelings of the respondents toward the Apil B as a culture fair assessment, specifically in relation to validity, reliability, cultural fairness, and bias. Although most of the questions are qualitative, quantitative questions are also included. Therefore, this research requires numerical data as well . The quantitative questions include yes and no responses, as well as rating scales. The quantitative data supplements the qualitative data and therefore facilitates a more concrete data base. The results indicate that all respondents feel that the Apil B is valid, reliable, culture fair and fairly applied . Respondents feel more positively toward the new updated psychometric tests. They expressed greater confidence in terms of knowing which tests are inappropriate and which tests are relevant to specific jobs. It is also evident that the Employment Equity Act has strongly influenced the attitudes of respondents, in a very positive light, toward the use of psychometric testing. The respondents do however mention some concerns with regard to language based tests, and the ethical use of tests. According to the research conducted, the Apil B is regarded as a valid, reliable, and culture fair assessment tool in the opinion of the respondents utilised in this study. It is therefore recommended that the Apil B is used in organisations as a test that does not discriminate against any culture or subculture. / Thesis (M.A.)-University of Natal, Durban, 2000.

Sammenfatning Baggrund og formål: Apopleksisygdommen er ansvarlig for flest tilfælde af invalidering blandt voksne i eget hjem. I Danmark alene lever godt 50.000 mennesker med følgerne efter apopleksi. En følge kan være reduceret evne til at kommunikere, afasi. Forebyggelse kan reducere antallet af nye tilfælde og følgerne efter sygdommen. Livskvalitet ved kronisk sygdom har voksende bevågenhed. Rehabilitering medvirker til at patienten kan blive fysisk, psykisk og socialt fungerende på et niveau, men sygdommens indvirken på oplevelsen af helbredsrelateret livskvalitet er i Danmark ikke undersøgt med sygdomsspecifikke instrumenter. Patienter med afasi udelukkes som regel fra undersøgelser, der kræver intakt tale og forståelse. Afhandlingens overordnede mål er at tilvejebringe et instrument, som kan anvendes til at måle helbredsrelateret livskvalitet efter apopleksi inkl. afasi. Metode og materiale: Afhandlingen har en kvantitativ tilgang. Et nordamerikansk instrument, Stroke Specific Quality of Life Scale, version 2.0, SSQOL © (copyright Linda S. Williams), er blevet oversat og kulturelt bearbejdet til dansk i overensstemmelse med anerkendt systematik i studie I. Instrumentet dækker med 49 items 12 domæner med fysisk, socialt og mentalt fokus samt 13 items, der dækker en vurdering af domænerne og livskvaliteten sammenlignet med før apopleksien. Instrumentets psykometriske egenskaber er blevet testet ved hjælp af tre studiepopulationer rekrutteret dels retrospektivt, dels konsekutivt. I studie II blev reliabilitet og validitet undersøgt, og i studie III responsivitet og sensitivitet. Afprøvningerne er foretaget med referenceformularer som eksterne kriterier i form af etablerede generiske skalaer. I studie IV er afprøvet en proxy-version tiltænkt patienter, som er ude af stand til selv at udfylde skemaet eller som ikke er i stand til at kommunikere tilstrækkeligt. Afprøvningen blev udført af en nærtstående udpeget af patienten. I studie V blev en gruppe let ramte patienter beskrevet, og variabler med betydningsfuld sammenhæng med oplevelsen af forringet helbredsrelateret livskvalitet blev undersøgt. Data er blevet testet ved hjælp af gennemsnit og standarddeviationer, median og range, proportioner, korrelationer og logistisk regression. Resultater: Den danske version af SSQOL, SSQOL-DK, har god face- og indholdsvaliditet. Det udfyldes på 10-20 minutter. Stabilitet, undersøgt med test-retest metode, viste korrelationer i området rs 0.65-0.99. Intern konsistens undersøgt med Cronbach’s alfa viste værdier i områderne 0.81-0.94 i studie II, 0.75-0.96 i studie III og 0.64-0.87 i studie V. Der blev set en ceiling effekt, 24-52%, men beskeden floor effekt. Begrebsvaliditet viste moderat delte varianser med de eksterne kriterier, r2 0.03-0.62. Konvergent validitet var (r) > 0.40 med undtagelse af et enkelt item. SSQOL-DK var i stand til at klassificere retning af ændring i livskvalitet over tid i overensstemmelse med eksterne kriterier i 43-58 % af tilfældene. Proxy-versionen viste god overensstemmelse mellem patient- og proxy data. I en gruppe af let ramte patienter med apopleksi og transcerebral iskæmi, TCI, et år efter sygdommen vurderede 57 % deres livskvalitet som uændret i forhold til før apopleksien. Det mandlige køn (OR 3.77), erhvervsaktivitet (OR 2.84), og lavere scores på domænerne Mood og Work ved tre måneder var covariater, som var signifikant relateret til sandsynligheden for at vurdere livskvaliteten forringet efter sygdommen. Konklusion: Der foreligger nu et dansksproget instrument, SSQOL-DK, som har demonstreret tilfredsstillende reliabilitet og validitet, og som kan anvendes på gruppeniveau til dansktalende patienter med let til moderat apopleksi. Apopleksipatienten med større kommunikationsproblemer har dog stadig begrænsede muligheder med dette instrument, idet de foreliggende resultater fra proxy-afprøvningen fordrer yderligere undersøgelse af datas validitet / Abstract Background and aim: Stroke is most frequently the cause of adult disability. In Denmark more than 50.000 people suffer from the sequels of stroke. One of them may be aphasia, i.e. reduced ability to communicate. Primary and secondary prevention may reduce the incidence and the severity of stroke. The interest in quality of life with a chronic disease is increasing. Rehabilitation efforts are targeted for physical, mental and social function but the impact on health related quality of life after stroke has not been studied with stroke specific instruments. Aphasic patients are normally excluded from studies where communicative skills are required. The aim of this thesis is to develop an instrument suitable for measuring health related quality of life after stroke. Methods and material: The design of the thesis is quantitative. In study I Stroke Specific Quality of Life Scale, version 2.0, SSQOL © (copyright Linda S. Williams), an American instrument recently developed, was translated and culturally adapted to Danish according to established guidelines. With 49 items SSQOL covers 12 domains comprising physical and mental issues. Thirteen items covers an appraisal of each domain compared to pre stroke status and overall quality of life. Psychometric properties was examined by studying three samples of stroke survivors. Study II and III examined reliability, validity and responsiveness. Established generic scales were used as external criteria. Study IV tested a proxy-version meant for stroke patients with language impairment or patients who are unable to fill in a questionnaire. The patients chose the proxies. Study V provided health related quality of life in a group of mildly affected patients after stroke or transient ischemic attack, TIA. Significant covariates with deteriorated health related quality of life were studied. Data were analyzed with mean and standard deviations, median and range, proportions correlations and logistic regression. Results: The Danish version of SSQOL, SSQOL-DK, showed good face- and content validity. It can be completed in less than 25 minutes. Test-retest showed correlations rs 0.65-0.99. Internal consistency showed Cronbach’s alpha from 0.81-0.94 in study II, 0.75-0.96 in study III and 0.64-0.87 in study V. Ceiling effect was 24-52%, floor-effect was modest. Construct validity showed shared variance with external criteria, r2 0.03-0.62. Convergent validity showed (r) >0.40 for 48 out of 49 items. SSQOL-DK classified direction of change in over all quality of life concordantly from 43-58% with external criteria. The agreement between patient- and proxy data was good. Fifty seven (57) percent of mildly affected patients after stroke or TIA rated their overall quality of life unchanged one year after stroke compared to pre stroke status. In the regression model male sex OR 3.77), working outside home (OR 2.84), and less than 5.00 (maximum score) on the domains Mood and Work/productivity at three months were significant predictors for rating over all quality of life deteriorated at 12 months. Conclusion: The SSQOL-DK has demonstrated satisfactory reliability and validity and can be used on group level measuring health related quality of life among Danish survivors after mild to moderate stroke and TIA. Stroke survivors with severe communication problems are still limited as validity of the proxy data should be further tested

Objectives: Dysregulation of the hypothalamus-pituitary-adrenal (HPA) axis has frequently been reported in multiple sclerosis (MS). So far, HPA axis function in MS has predominantly been studied under pharmacological stimulation which is associated with a series of methodological caveats. Knowledge of circadian cortisol patterns and cortisol awakening response (CAR) is still limited. Methods: A total of 77 MS patients (55 relapsing-remitting MS (RRMS)/22 secondary-progressive MS (SPMS)) as well as 34 healthy control (HC) subjects were enrolled. Diurnal cortisol release was assessed by repeated salivary cortisol sampling. Neurological disability was rated by the Kurtzke’s Expanded Disability Status Scale (EDSS). Depressive symptoms and perceived stress were assessed by self-report measures. Results: RRMS but not SPMS patients differed in circadian cortisol release from HC subjects. Differences in cortisol release were restricted to CAR. Treated and treatment naïve RRMS patients did not differ in CAR. In a RRMS follow-up cohort (nine months follow-up), RRMS patients with EDSS progression (≥0.5) expressed a significantly greater CAR compared to HC subjects. RRMS patients with a stable EDSS did not differ from HC subjects. Neither depressive symptoms nor perceived stress ratings were associated with CAR in RRMS patients. In a step-wise regression analysis, EDSS at baseline and CAR were predictive of EDSS at follow-up (R2 = 67%) for RRMS patients. Conclusions: Circadian cortisol release, in particular CAR, shows a course specific pattern with most pronounced release in RRMS. There is also some evidence for greater CAR in RRMS patients with EDSS progression. As a consequence, CAR might be of predictive value in terms of neurological disability in RRMS patients. The possible role of neuroendocrine-immune interactions in MS pathogenesis is further discussed.

Un diagnostic de cancer du sein met la relation d’un couple à l'épreuve. La communication à propos du cancer peut aider les conjoints à s’appuyer mutuellement afin de mieux s’adapter à la maladie. Cependant, dans la documentation existante, peu d’échelles mesurent explicitement cette forme de communication. Ce projet avait pour but de valider l’échelle de communication des couples aux prises avec le cancer (CCC). Les patientes (N = 120) et leurs conjoints (N = 109) ont été interrogés au sujet de leur expérience avec le cancer du sein. Une analyse factorielle performé sur l’ensemble des données a permis de retenir deux facteurs pour l’échelle CCC, l’évitement et l’ouverture à la communication. L’échelle a démontré une bonne validité convergente avec le Primary Communication Inventory (r = .54, p <.01 patientes; r = .55, p <.01 partenaires). Finalement, l’échelle CCC prédit la dépression (Δr² = 0.029) et l’ajustement marital (Δr² = 0.032) au-delà de la communication générale. Avec plus ample développement, l'échelle actuelle pourrait servir à des fins de recherche ainsi que dans des contextes cliniques où une évaluation après un diagnostic de cancer permettrait, au besoin, la mise en oeuvre précoce d’interventions sur la communication conjugale au propos de la maladie. / A diagnosis of breast cancer powerfully challenges a couple’s relationship. Couple illness communication is one way couples offer each other mutual support, allowing for better illness adjustment. However, in the existing literature, few scales explicitly measure couple illness communication. The goals of the present study were to validate the Couple Cancer Communication scale (CCC) and to examine the association between CCC and cancer-related adjustment outcomes. Patients (N = 120) and their spouses (N = 109) were interviewed regarding their experience with breast cancer. A two factor solution was retained for the CCC scale, avoidance and openness to communication. It demonstrated good convergent validity with the Primary Communication Inventory (r = .54, p <.01 for patients; r = .55, p <.01 for partners). Finally, the CCC scale significantly predicted both depression (Δr² = 0.029) and marital adjustment (Δr² = 0.032) scores above and beyond general communication. With further development, the CCC could be a useful tool as an assessment measure in a life-threatening disease. The present scale, in conjunction with other sources of information, could be used in future research and clinical settings when attempting to assess illness-related communication and related outcomes.

Objective: The Six Elements Task (SET; Shallice and Burgess, 1991; Burgess et al., 1996) measures examinees’ ability to plan and organize their behaviour, form strategies for novel problem solving, and self-monitor. The task has adequate specificity (Wilson et al., 1996), but questionable sensitivity to mild impairments in executive function (Jelicic, et al., 2001). The SET is vulnerable to practice effects. There is a limited range in possible scores, and ceiling effects are observed. This dissertation sought to evaluate the validity and clinical utility of a modification of the SET by increasing the difficulty of the test, and expanding the range of possible scores in order to make it more suitable for serial assessments. Participants and Methods: The sample included 26 individuals with mixed acquired brain injury, and 26 healthy matched controls (20 – 65 years). Participants completed a battery of neuropsychological tests on two occasions eight weeks apart. To control for confounding variables in executive function test performance, measures of memory, working memory, intelligence, substance abuse, pain, mood and personality were included. Self and informant reports of executive dysfunction were also completed. The two groups’ performances on the various measures were compared, and the external validity of the 12ET was examined. In addition, normative data and information for reliable change calculations were tabulated. Results: The ABI group exhibited very mild executive function deficits on established measures. The matched control group attempted more tasks on the 12ET, but the difference was non significant. Neither group tended to break the rule of the task. The 12ET showed convergent validity with significant correlations with measures of cognitive flexibility (Trailmaking B and Ruff Figural Fluency), and a measure of planning (Tower of London). The 12ET and published measures were also significantly correlated with intelligence in the brain-injured group. The 12ET did not show divergent validity with a test of visual scanning speed (Trailmaking A). No demographic variables were found to be significant predictors of 12ET performance at Time 2 over and above performance at Time 1, and both participant groups obtained the same benefit from practice. The 12ET did not suffer from ceiling effects on the second administration, and the test-retest reliability of the 12ET variables ranged from low (r = .22 for Rule Breaks in the brain-injured group) to high (r = .78 for Number of Tasks Attempted in the control group). Conclusions: Despite their (often severe) brain injuries, this sample of brain injured participants did not demonstrate executive impairments on many published tests and their scores were not significantly different from the control group’s scores. Therefore, it was not possible to determine if the 12ET was a more sensitive measure of mild executive deficits than the SET. However, the increase in range did reduce the tendency for participants to perform at ceiling levels. The 12ET showed a number of significant correlations with other executive measures, particularly for the brain-injured group, though these correlations may have been moderated by general intelligence. Two variables of the 12ET, deviation from the optimal amount of time per task and Number of Tasks Completed, showed promise as measures of reliable change in this sample over an 8-week interval.

The Patient-Centred Assessment of Symptoms and Activities (P-CASA) is a new idiographic, open-ended assessment that examines each individual patient’s symptoms within the context of his or her daily life. P-CASA asks patients for their most important activities, what interferes with these activities, and any coping strategies. This thesis presents the rationale and design of P-CASA and its first validation study. Sixty patients at the Pain and Symptom Management/Palliative Care Clinic of the BC Cancer Agency (Vancouver Island Centre) completed P-CASA and the Edmonton Symptom Assessment System (ESAS), which is the current nomothetic assessment at the Clinic. The results demonstrated that P-CASA was not redundant with ESAS because it assessed (a) information about patients’ activities and coping strategies, which the ESAS does not; (b) all relevant cancer-related symptoms (not just pain or a fixed list); (c) co-occurring symptoms; (d) more specific details and different priorities about symptoms than in their ESAS. / Graduate

Cette thèse avait pour objectif général d’approfondir nos connaissances sur les rêves dysphoriques (mauvais rêves et cauchemars), selon deux axes. Premièrement, nous avons voulu éclaircir les implications méthodologiques reliées aux différentes mesures de la fréquence de rappel de rêves (articles 1 et 2). Deuxièmement, nous avons voulu étudier un aspect encore peu exploré des rêves dysphoriques : leur contenu (article 3). Dans la première étude, nous avons comparé systématiquement différentes méthodes rétrospectives et prospectives utilisées pour mesurer la fréquence des cauchemars et des mauvais rêves chez 411 participants. En plus de reproduire les résultats d’études antérieures selon lesquelles les mesure rétrospectives sous-estiment la fréquence des rêves dysphoriques, nous avons démontré que ces fréquences n’étaient pas affectées de manière différentielle par le format de la mesure prospective (journaux de rêves narratifs ou à choix de réponse). Dans la deuxième étude, nous nous sommes intéressés à la fréquence de rappel onirique en général (i.e. de tous les rêves) auprès d'un échantillon de 358 participants pour approfondir les résultats relatifs à la comparaison entre les deux types de journaux de rêves obtenus dans la première étude. Nos résultats soulignent que la fréquence de rappel obtenue par un journal à choix de réponse est plus élevée que celle obtenue d’un journal narratif, et que le présumé effet d’augmentation de rappel attribué aux mesures prospectives est limité dans le temps. Ces résultats suggèrent que des facteurs motivationnels sont impliqués dans la tenue d’un journal de rêves, et que dans le cas des journaux narratifs, ces facteurs outrepasseraient les facteurs attentionnels favorisant le rappel onirique. Dans la troisième étude, nous avons comparé le contenu de 253 cauchemars et 431 mauvais rêves obtenus prospectivement auprès de 331 participants, offrant ainsi l’une des descriptions de ce type des plus détaillées à ce jour. Nos résultats démontrent que cauchemars et mauvais rêves partagent de nombreuses caractéristiques mais se différencient en plusieurs points : le contenu des cauchemars est davantage caractérisé par des menaces physiques, et celui des mauvais rêves par des menaces psychologiques. De plus, les cauchemars ont plus souvent la peur comme émotion principale, ont une intensité émotionnelle plus forte, se terminent plus souvent de façon négative et sont plus bizarres que les mauvais rêves. Ces différences de contenu entre mauvais rêves et cauchemars suggèrent que ces deux types de rêves sont des manifestations d’un même phénomène variant en termes d’intensité, et que cette intensité est multidimensionnelle. Les résultats de l’étude 3 sont discutés en lien avec différentes théories sur l’étiologie et la fonction des rêves. / The overall goal of this thesis was to further our understanding on disturbed dreaming (bad dreams and nightmares) along two main lines of inquiry. First, we examined the methodological implications associated with the different instruments used to measure dream recall frequency (articles 1 and 2). Second, we investigated the actual content of disturbing dreams, a dimension for which empirical data remain surprisingly scarce (article 3). Study 1 compared the frequency of nightmares and bad dreams obtained with retrospective methods and with two types of prospective instruments (narrative and checklist logs) in 411 participants. In addition to replicating findings showing that when compared to daily logs, retrospective self-reports underestimate current nightmare and bad dream frequency, we showed that these frequencies were not differentially affected by the type of prospective log. Our second study extended these findings by comparing the differential effects of narrative and checklist logs on general dream recall in 358 participants. The results indicate that checklist logs yield higher prospective dream recall frequency than narrative logs, and that prospectively measured dream recall frequency tends to peak at the beginning of the log and then remains stable over time. Thus, improved dream recall arising from subjects' increased attention towards their dreams is short-lived and the effect quickly offset by motivational factors. Our third article presents a comprehensive and comparative description of the content of 431 bad dreams and 253 nightmares collected prospectively from 331 participants. The results indicate that although nightmares and bad dreams share many content characteristics and features, they also differ along several dimensions: nightmares tend to involve physical threats whereas psychological threats predominate in bad dreams; nightmares are more likely than bad dreams to contain fear as their principal emotion as well as being significantly more emotionally intense; and when compared to bad dreams, nightmares are more bizarre and contain significantly more aggressions, failures, and unfortunate endings. Taken together these findings support the view that nightmares represent a more intense expression of the same basic phenomenon and that this intensity manifests itself along a number of content dimensions. These results are discussed in relation to different theories on the etiology and function of dreams.