The time course of peri-infarct diaschisis following a focal ischemic infarct and the effects of delayed rehabilitation on behavioral and functional recovery were examined. Intracortical microstimulation (ICMS) was used to derive topographical maps of forelimb representations within the rat motor cortex and ischemia was induced via bipolar coagulation of surface vasculature. At one hour there was a dramatic expansion of reprentations in control but not ischemic animals. A significant loss of forelimb representations within peri-infarct dysfunction indicates the need for immediate administration of therapeutic interventions following an ischemic event. These results indicate that the timing of rehabilitation does not effect functional and behavioral recovery but does support the need for rehabilitative interventions of facilitate these types of recovery. / 132 leaves : ill. ; 28 cm.

L’âge, le génotype et les traumatismes crâniens (TCC) sont trois facteurs de risque majeurs du développement de la maladie d’Alzheimer (MA). Avec une accumulation d’évidences démontrant la persistance d’anomalies cérébrales suite aux plus légers des TCC, qui affichent d’ailleurs la plus haute incidence, il devient impératif de tester l’hypothèse selon laquelle même les commotions cérébrales puissent interagir avec l’âge et les gènes afin de précipiter la neurodégénération. Trente ex-athlètes de haut niveau (âge M = 60 ans), dont la moitié a subi des commotions cérébrales il y a plus de 30 ans, ont été évalués en neuropsychologie, en neuroimagerie multimodale ainsi qu’en génétique. De nombreuses mesures neuroanatomiques, dont l’expansion du volume des ventricules latéraux, se trouvent à corréler avec divers déficits cognitifs (mémoire différée et de reconnaissance) détectés chez les participants commotionnés. D’un intérêt particulier, certains de ces résultats sont modulés par le polymorphisme nucléotidique simple du gène Apolipoprotéine E. Ces résultats appuient l’hypothèse selon laquelle la commotion cérébrale chez de jeunes athlètes serait un facteur de risque de neurodégénération dans le vieillissement normal. / Age, genotype and traumatic brain injury (TBI) are three of the most important risk factors of Alzheimer’s Disease. With a growing body of evidence showing the persistent deleterious effects of the mildest form of TBI, it becomes imperative to test the hypothesis that sports concussion could interact with aging to precipitate neurodegeneration. Thirty former high-level athletes (mean age = 60 yrs), half of them having sustained sports concussion during their young adulthood, underwent neuropsychological, neuroanatomical and APOE genotype examination. Data analysis revealed numerous neurobiological anomalies, such as ventricular enlargement, correlating with cognitive deficits (delayed and recognition memory) in concussed participants. Of particular interest, some neuroanatomical measures were found to be modulated by APOE single-nucleotide polymorphisms. These findings support the idea that sports concussions sustained in early adulthood are a risk factor of neurodegeneration in late adulthood.

This thesis deals with psychological issues concerning patients with malignant gliomas, and their spouses. There is no known medical cure, and the patients have a limited survival expectancy. Therefore studies evaluating new treatment modes, an overall supportive atmosphere, and attempts to avoid imposing unnessesary strain are necessary. Thirty consecutive patients with astrocytomas, grade III-IV, were included in a clinical trial with estramustine phosphate in addition to conventional treatment with surgery and radiotherapy. Both the patients and their spouses participated in the present study which aimed at a deeper understanding of the psychological processes relevant to their situation. By means of repeated thematically structured interviews, patients and spouses were followed separately during the entire course of the disease process. In addition to these interviews, all patients were assessed with a mini-mental examination, and five-month survivors were tested with a comprehensive neuropsychological battery. Questionnaires on reaction to the diagnosis and assessing psychosocial well-being were also administered to the patients. The interviews were analysed with grounded theory methodology and the findings were juxtaposed to concepts in psychoanalysis and coping theory. The main finding was that the patients, despite or owing to their severe medical situations, showed a marked capacity to create protection and hope. By means of biased perception they created an 'illusion' that palliated their strain. This finding is related to object-relational psychoanalysis with obvious implications for the crucial discussion on telling bad news. Another finding was that the spouses displayed different crisis trajectories depending on the overall status of their partners. Different senses of the relationship were related to different modes of coping. Especially spouses to patients with personality changes were put under severe strain and ought to be acknowledged by medical staff. Patients with no obvious deficits five months after termination of primary treatment nevertheless evidenced, at neuropsychological testing, a pronounced deficiancy in long-term memory, but no clear impairment in global intellectual capacities. Estramustine phosphate was found to have a negative impact on sexuality and might be one causative agent behind the decline in long-term memory, but these adversive effects did not seem to affect psychosocial well-being. The selective reminding technique proved to be sensitive in detecting deficits and is recommended in future clinical trials affecting the CNS. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1996, härtill 5 uppsatser.</p> / digitalisering@umu

The relationship between lesion volume in children with traumatic brain injury (TBI) and IQ scores was investigated in this study. Participants included eight children between the ages of 8-12 years with primarily right hemisphere TBIs and 16 normals who were matched based on age and gender. Archival data employing the Wechsler Intelligence Scale for Children - III (WISC-III) scores was the source of Verbal IQ (VIQ), Performance IQ (PIQ), and Full Scale IQ (FSIQ) scores. Severity of injury was determined using the Glasgow Coma Scale (GCS) which was contained in the same archival database. Lesion volume was determined utilizing National Institute of Health (NIH) Image (Version 1.76) and magnetic resonance imaging scans of the injured children. The area of the lesion was outlined, using the freehand line tool, on successive slices, summed, and multiplied by the corresponding acquisition slice gap to obtain a measure of total volume. Results indicated that lesion volume does not explain a significant portion of the variance associated with TBI. Severely injured children had lower IQs than children with mild or no injury. Additionally, children with right hemisphere injuries had significantly lower VIQ, PIQ, and FSIQ scores than normals. Qualitative analyses revealed that lesion volume appears to be related to the change in IQ scores during recovery. Typically, children with larger lesions (e.g., more severe injury) had greater functional losses and had greater gains to make; therefore, they demonstrated greater changes in IQ score as compared to less severely injured children. Predicting the area of deficit based upon lesion location yielded results congruent with chance. Results appear to reinforce the complexity of TBI; no single piece of data explains a significant portion of the variance associated with this phenomenon. Future research should strive toExamine and control for the numerous factors associated with TBI (e.g., age, lesion location, lesion volume, premorbid abilities, parental education, GCS score, gender, use of standard test battery, and many others) within a single study. Efforts to provide optimal treatment and recovery of TBI patients could be informed by such research. / Department of Counseling Psychology and Guidance Services

The primary purpose of this study was to determine the kind of neuropsychological information that can be obtained from an investigation of the Wechsler Adult Intelligence Scale (WAIS) subtests. Additionally, there was an examination of the shared variance between the WAIS and the Halstead-Reitan Neuropsychological Battery (HRNB). The archival data collected from the files of '220 females and 188 males from a large midwestern medical center were used. They had been originally diagnosed with objective research criteria.All eleven subtests of the WAIS and the HalsteadReitan Neuropsychological Battery were administered to the subjects in the years between 1981 and 1983. Thirteen scores were obtained from the HRNB measures. Statistical analyses of the results made use of the techniques of multiple regression and canonical correlation.The individual WAIS subtests were examined for the neuropsychological information they provided. Globally, three HRNB measures, APHASIA, RHY, AND CAT-TOT contributed significantly to a majority of the regression equations for the WAIS subtests. Their presence suggested that language skills, an auditory attention factor, and a general intellective factor were being tapped (Dean, 1985a).A canonical correlation was computed. The results yielded one significant correlation between the linear components of the WAIS and the HRNB tests. Only canonical variates with weights of +/- .2 were considered large enough for interpretation. The WAIS subtests meeting the .2 criteria included Block Design, Digit Symbol, and Similarities, while the HRNB measures meeting criteria were APHASIA and CAT-TOT. Therefore, it would appear that the significant variables measured the general (g) factor as in Spearman's research (1927). According to the Stewart and Love formula (cited in Pedhazur, 1982), the variability of the WAIS did overlap with the HRNB, and their relationship was symmetrical.This research demonstrated that the measured tasks from the WAIS were a complex of underlying constructs. The verbal portion of the WAIS was shown to be less highly related to the HRNB variables than the performance portion of the scale. The WAIS and HRNB do offer nonredundant information concerning the impaired and unimpaired adult's cognitive functioning.

The aim of this study was to come to a better understanding of possible neuropsychological mechanisms underlying psychosocial well-being and therefore to determine whether a relationship between neuropsychological executive functions and psychosocial well-being does indeed exist. Research was conducted in the domains of neuropsychology and positive psychology. This thesis consists of three articles, namely I ) Neuropsychological executive functions and psychosocial well-being: A review, 2) Attentional switching and psychosocial! well-being, and 3) The relationship between generativity as neuropsychological process and psychosocial well-being. The first article argued the possibility of a relationship between neuropsychological and psychosocial aspects, with reference to a pluralistic ecosystems perspective, neuropsychological and other positive psychological theories, such as Miller's neuropsychodynamic model and Frederickson's broaden-and-build theory, as well as existing empirical studies. Numerous neuropsychological studies have indicated that the prefrontal cortex is involved in executive functions, with its main function to regulate both cognitive and affective functioning. Analyses of existing empirical studies indicated an established relationship between prefrontal lobe / executive / regulatory dysfunction and psychopathology, but also that the relationship between normal or optimal prefrontal executive functions and psychosocial well-being is still unclear. The first article concluded that evidence correlating neuropsychological functioning with human flourishing, or indicating possible neuropsychological mechanisms involved in psychosocial well-being, is sparse, presenting a serious lacuna in scientific knowledge. The following two articles focused on contributing to filling this lacuna. "Attentional switching and psychosocial well-being" and "The relationship between generativity, as neuropsychological process and psychosocial well-being" focused on attentional switching and generativity, as part of neuropsychological executive functions, as potential mechanisms associated with psychosocial well-being. These studies aimed to determine whether the capacity to switch attention, as measured by the Color Trails Test (CTT) and Wisconsin Card Sorting Test (WCST), and the capacity to generate novelty, as measured by the Controlled Verbal Fluency Task (CVFT) (Benton, 1967) and Uses of Objects Test (UOT) (Getzels & Jackson, 1962), are related to the degree of psychosocial well-being experienced. As part of the interdisciplinary POWIRS (Profiles of Obese Women with Insulin Resistance Syndrome) project, black African women (article 2 n=66; article 3 n=72) completed the above mentioned neuropsychological measures, as well as indices of psychosocial wellbeing, in a cross-sectional design. The psychosocial measures included the Affectometer (AFM) 2 (Kammann & Flett, 1983); Constructive Thinking Inventory (CTI) abbreviated version (Epstein & Meier, 1989); Sense of Coherence Scale (SOC- 29) (Antonovsky, 1987, 1993); The Fortitude Questionnaire (FORQ) (Pretorius, 1998); JAREL Spiritual Well-being Scale (SWS-H) (Hungelman et al., 1989); Psychological Well-being Scales (SPW-B) (Ryff & Singer, 1998); and the Cognitive Appraisal Questionnaire (CAQ) (Botha & Wissing, 2003). The main findings of these studies were hat the ease of attentional switching and generativity correlates statistically (p<0.5) and practically significantly with higher levels of psychosocial well-being. From a micro-deterministic perspective it can be concluded that frontal lobe executive functions may play a role in the regulation higher-order adjusting psychosocial functions related to quality of life. From a micro-deterministic perspective it can be concluded that psychosocial well-being, while being influenced by executive functions, may also influence the continuous development of neuropsychological executive functions. / Thesis (Ph.D. (Psychology))--North-West University, Potchefstroom Campus, 2005.

Objectives: Most researchers have attributed observed cognitive differences between individuals with a traumatic brain injury (TBI) and ‘normal’ individuals to physiological changes to the brain. Lacking exploration has been the role of social context/environmental variables. One of the variables investigated in the social psychology literature is stereotypes. Research has shown that the presence of stereotypes in testing environments negatively interferes with test performance (called stereotype threat theory). This concept appears relevant to the TBI population given that empirical research has demonstrated that individuals tend to believe that traumatic brain injuries lead to cognitive deficits, as well as the fact that reminders of potential cognitive deficits are oftentimes present in neuropsychological testing settings (e.g., in pre-test instructions, etc.). It is argued that these cues exacerbate pre-existing negative beliefs regarding cognitive functioning for individuals with a mild-moderate TBI, thereby affecting neuropsychological test performance. Method: The sample consisted of 42 individuals who sustained a mild-to-moderate TBI at least 6 months earlier and 42 age-, gender-, and education-matched healthy adults below the age of 60. The study, similar to other stereotype threat research, consisted of ‘reduced threat’ and ‘heightened threat’ conditions. The purpose of the former condition was to reduce negative stereotypes and emphasize the notion of personal control over cognitive abilities. Questionnaires and neuropsychological tests were administered subsequent to the experimental manipulation. Results: TBI participants endorsed greater levels of anxiety, motivation, and dejection, but reduced feelings of memory self-efficacy compared to the control group. The most pivotal results to the research study revealed that the TBI heightened threat group displayed lower scores on the Initial Encoding and Attention composite variables (which were comprised of neuropsychological test measures) than the TBI reduced threat group. Furthermore, the head-injured heightened threat condition reported lower memory self-efficacy than the reduced threat condition, and the non-head-injured heightened threat group endorsed a greater degree of negative beliefs/stereotypes regarding TBI than the non-head-injured reduced threat group. The construct of memory self-efficacy was found to mediate the relation between threat condition and performance on encoding/attention measures. Conclusions: The findings highlight the role of negative stereotypes and expectations/beliefs to cognitive test performance in individuals who have sustained a mild/moderate TBI. To date, there have been few attempts to integrate social cognition with neuropsychology. Applying the information gleaned from previous stereotype threat studies to a TBI population bridges this gap and provides a prosperous avenue for future research.

Mild Traumatic Brain Injury (mTBI), often called concussion, has become a growing public health concern, prevalent in both athletic and military settings. In response, many researchers have explored cognitive outcomes post-mTBI, with a plethora of meta-analyses summarizing these findings; however, these meta-analyses examine solely mean performances on cognitive tasks, ignoring intra-individual variability (IIV) in cognitive performance that may elucidate neuropsychological impairment following mTBI. The current thesis involved two studies, responding to both the growing meta-analytic research and limited IIV findings. Study 1: Many meta-analyses have amalgamated individual study results on post-mTBI neuropsychological outcomes. With the abundance of meta-analyses, a systematic review of meta-analyses stands as the next logical step. Method: A systematic literature search yielded 11 meta-analyses meeting inclusion criteria (i.e., English-language systematic reviews/meta-analyses covering post-mTBI observational cognitive research on late adolescents/adults), with their findings qualitatively synthesized based on moderator variables (i.e., cognitive domain, time since injury, past head injury, participant characteristics, comparison group, assessment technique, and persistent symptoms). Results: The overall effect sizes ranged for both general (range: .07-.61) and sports-related mTBI (range: .40-.81) and differed both between and within cognitive domains, with executive functions appearing most sensitive to multiple mTBI. Cognitive domains varied in recovery rates, but overall recovery occurred by 90 days post-injury for most individuals and by seven days post-injury for athletes. Greater age/education and male gender produced smaller effects sizes, while high school athletes suffered the largest deficits post-mTBI. Control-group comparisons yielded larger effects than within-person designs, while assessment techniques had limited moderating effects. Conclusions: Overall, meta-analytic review quality remained low with few studies assessing publication or study quality bias. Meta-analyses consistently identified adverse acute mTBI-related effects and fairly rapid symptom resolution. Study 2: The long-term outcomes of executive functions and IIV following mTBI are unclear due to inconsistent and limited research, respectively. Further, the relationship between physical activity (PA) and cognitive performance at young adulthood remains almost fully unexplored. In turn, the current study aimed to (a) assess the diagnostic utility of both executive functions and IIV at predicting mTBI history and (b) evaluate the interaction between PA levels and mTBI on both of these cognitive metrics. Method: Altogether 138 self-identified athletes (Mage = 19.9 ± 1.91 years, 60.8% female, 19.6% 1 mTBI, 18.1% 2+ mTBIs) completed three executive-related cognitive tasks (i.e., N-Back, Go/No-go, Local-Global). Ordinal logistic regression analyses examined the joint effect of person-mean and IIV as predictors of mTBI status. Multi-level models examined mTBI and PA levels as predictors of trial-to-trial changes in performance. Results: Only mean response time (RT) for the Local-Global task predicted mTBI status, while no IIV variables reached unique significance. PA levels predicted subtle within-task decreases in RT across Local-Global trials. Conclusions: IIV research on mTBI remains limited; however, the preliminary results do not indicate any additional predictive value of IIV indices above mean performances. For executive functions, shifting appeared most affected, with past researchers identifying post-mTBI impairment in attentional processing. Higher PA levels minutely benefited within-task shifting and mean inhibitory performance, although these finding require cautious interpretation. / Graduate / 0622 / jkarr@uvic.ca

"This work explores how current embodied theories of cognition can account for the comprehension of narrative texts. Theoretically, this thesis develops a framework for the study of narrative text comprehension by linking current advances in embodied theories of cognition, discourse processing, and neurosciences. Experimentally, two experiments are reported in which participants were required to read passages of text implying emotional states. The coherence of critical sentences in relation to the preceding text was manipulated in terms of both the emotional adjectives used and the sensory-motor component. In the first experiment, three tasks were used to index the effect of the manipulations on the critical sentences. The first was an on-line naming task in which response times to name emotional labels which matched the implied emotional state of the texts were recorded. [...] The second experiment used backward masking in the naming task with the aim of providing a more sensitive index of the effect of the text manipulations on on-line processing." / Master of Applied Science by research

ABSTRACT Exploitation of older people can result in devastating emotional and financial consequences. Researchers and policy makers have widely recognised the deleterious effects of exploitation on older adults, particularly cognitively impaired older people. Studies to date have provided basic information about the demographic and health characteristics that contribute to exploitation in later life, namely extreme dependence, frailty, social isolation, severe physical illness, and cognitive impairment. However, an overarching explanatory framework of vulnerability, and clinical instruments to aid with identifying those individuals at elevated risk of exploitation a priori have been lacking. Furthermore, the specific cognitive and social factors at the level of the individual which promote vulnerability to exploitation remain largely unexplored. The present research was directed towards addressing these issues. For definitional purposes, the term social vulnerability is used throughout in reference to an individual’s degree of susceptibility to exploitation. Exploitation of older people can take many forms including social and sexual exploitation, mistreatment, and deprivation of rights. Financial exploitation in particular is a relatively widespread phenomenon among older people, and may be a salient marker of social vulnerability in later life. In Chapter 1 of this dissertation, literature relevant to financial exploitation and social vulnerability more generally among older people is reviewed, and a conceptual framework for describing and explaining heightened vulnerability is presented. Central to this framework are various factors of personal competence at the level of the individual (i.e., intelligence, cognitive functioning, social intelligence, social skill, personality traits) which, in theoretical terms, contribute to, or protect against, exploitation. Chapter 2 details the development and psychometric evaluation of a standardised scale for assessing social vulnerability among older adults (termed the SVS15). Given that financial exploitation may be a pertinent marker of social vulnerability in older people, item content for the scale includes items of a financial nature. The results of two studies provided support for the reliability (internal consistency) and validity (known-groups) of the SVS15. Results of a factor analysis revealed a two-factor solution, with the emerging factors labelled gullibility and credulity. Stability in factor structure of the SVS15 was established in an independent sample using structural equation modelling. Chapters 3 and 4 of the dissertation detail the methodology employed in, and results of, a series of three studies systematically investigating the relationships between personal competence factors and social vulnerability in older people. Using multiple regression analyses, non-significant associations between basic demographic characteristics and social vulnerability were found in a nonclinical older sample, indicating that heightened vulnerability to exploitation is not readily explained by age, gender, or education. Rather, general cognitive functioning emerged as the most significant correlate of SVS15 scores in a combined clinical and nonclinical sample of older adults such that poorer cognitive functioning was associated with greater vulnerability to exploitation. Executive functioning in particular showed significant overlap with SVS15 scores after controlling for differences in memory and age. These results support the inclusion of standardised neuropsychological tests of memory and executive functioning (tests which are routinely used) when issues of social vulnerability arise. After general cognitive functioning, social measures of self-awareness and social skill were also important correlates of social vulnerability scores, indicating that social measures could also contribute useful information when assessing social vulnerability in older people. From an applied perspective, Chapter 5 of the thesis presents normative data for the SVS15, and an examination of the Tclinical utility of the scale using individual case studies of older adults diagnosed with a dementia syndrome. In Chapter 6, an amalgamation of the results from the project is presented, and the theoretical and clinical contributions of the findings are highlighted. TThe findings contribute to the extant literature in two ways: (1) through the development of aT potentially useful and psychometrically sound instrument which targets symptoms of social Tvulnerability more directly than existing neuropsychological measures and (2) by enhancing the current understanding of the cognitive and social personal competence factors associated with heightened vulnerability in later life.